Bioscience Horizons The International Journal of Student Research

Calcium signalling is a complex and diverse system utilized in many cellular processes and in the transmission of cellular information. A number of transient receptor potential (TRP) proteins have been identified in humans and other mammals; these proteins are implicated as having a role in calcium signalling. TRPC5 is a member of this protein family which combines with TRPC1 to form non-selective cation channels in human saphenous vein cells, a type of smooth muscle cell. The exact function of TRPC5 remains elusive, however, it can be activated by sphingosine-1-phosphate (S1P), an endogenous signalling phospholipid involved in SMC migration. The aim of these experiments was to investigate the effects of S1P on the intracellular calcium concentration, [Ca²⁺]i, in HSV cells, utilizing dominant-negative (DN)-TRPC5 transfected cells to establish the role played by TRPC5 in this response. A secondary aim was to establish the effect of SMC migration on the above response parameters to S1P using the HSV scratch assay, where a ∼2 mm line of cells was scraped away from the surface of a glass cover slip and the remaining cells incubated for 24 h. Concurrent with the literature, S1P evoked a significant response in HSV cells (n=23; P=0.001). The baseline was significantly lower in the DN-TRPC5 cells compared with the control cells (P<0.001), and the maximum response in the DN-TRPC5 transfected HSV cells reached only 60% of the maximum response in control cells. This suggested that TRPC5 was involved with maintaining basal [Ca2+]i levels and indicated the proportion of the response for which TRPC5 was responsible. The response to S1P was significantly larger in migrated (n=7) compared with static (n=11) HSV cells (P=<0.001) and this response was delayed by ∼2.3 min; the baseline was also higher in the latter group. This suggested a functional change in the cell following migration that may have been attributable to TRPC5, for example, channel up-regulation. In conclusion, TRPC5-like channels are responsible for a proportion of the S1P response and are implicated in SMC migration. This highlights potential pharmacological targets for the treatment of atherosclerosis, neointimal hyperplasia and coronary heart disease.

Social network analysis (SNA) is a mathematical technique for analysing social relationships and the patterns and implications of these relationships (Wasserman S, Faust K (1994) Social Network Analysis: Methods and Applications . Cambridge: Cambridge University Press). It has only recently been discovered by behavioural biologists as a useful tool in the study of animal behaviour (Wey T, Blumstein DT, Shen W et al. (2008) Social network analysis of animal behaviour: a promising tool for the study of sociality. Anim Behav 75: 333–344). Video recording over a 2 month period was used to record the behaviour of the elephant group at Chester Zoo. SNA was applied in an investigation of the group structure and interactions of the group. Observations of individual and group behaviour were based upon 40 h of playback of the social interactions were recorded and analysed using AGNA (2003) and Pajek (2005) packages. The analysis showed that the many facets of individual behaviour could be understood in terms of social structure of the group. This study has demonstrated that SNA is a powerful approach to understanding group dynamics and is particularly applicable to the study of obligate social species. In conclusion, it is suggested that SNA is potentially a useful tool in the management of captive animal populations.

The aim of this study was to test the hypothesis that diverting the cytoplasmic subcellular localization of the anti-apoptotic form of Survivin to the nucleus would sensitize cancer cells to chemotherapeutics. Apoptosis is a morphologically and biochemically distinctive form of cell death, critical in the maintenance of tissue homeostasis. Caspases are a family of cysteine proteases that have a vital role in the implementation of apoptosis, and their activity is regulated by Inhibitors of Apoptosis Proteins. Recent studies indicate that one such inhibitor, Survivin, may have dual functions that are specific to its cellular location, including suppression of apoptotis (cytosolic) and regulation of cell division (nuclear). Since both apoptosis and proliferation are altered in cancer, identifying whether these roles for Survivin are dependent on its subcellular localization will inform future approaches to treat chemotherapeutically resistant tumour cells. After initially confirming the specificity of several Survivin antibodies, the distribution of Survivin was examined by immunofluorescence microscopy and sub-cellular fractionation in breast cancer cell lines. The threshold of drug-induced apoptosis was compared in cells over-expressing either wildtype Survivin or a form of Survivin unable to exit the nucleus due to a mutation in its nuclear export sequence. Endogenous Survivin localized to both nucleus and cytoplasm of breast cancer cell lines. Over-expressed Survivin had an anti-apoptotic, protective function. In contrast, cells expressing Survivin with the mutated nuclear export sequence had a lower apoptotic threshold to chemotherapeutic drugs. These results demonstrate for the first time that Survivin is localized to both the nucleus and cytoplasm of breast cancer cell lines. Importantly, the sensitivity of cells to chemotherapeutic drugs was increased when Survivin's localization was restricted to the nucleus, consistent with cytoplasmic Survivin having the anti-apoptotic role. Since clinical studies have shown that nuclear Survivin is a positive prognostic factor in breast cancer patients, the data suggest that strategies to alter Survivin distribution may be useful in the fight against cancer.

TWIK-related acid-sensitive potassium (TASK) channels have been implicated as having a role in maintaining and mediating the tone of pulmonary arteries by influencing the membrane potential of the smooth muscle cells. Inhibition of these channels would be expected to promote depolarization, calcium influx and contraction. The purpose of this study was to investigate the effects of TASK modulators on rat intrapulmonary artery tone. The modulators included pH, an important physiological TASK modulator, and drugs that inhibit TASK channels, such as bupivacaine, methanandamide and zinc. Small vessel myography was used to measure the tone of both conduit and resistance pulmonary arteries. Cumulative bupivacaine and methanandamide dose–response curves were compared with phenylephrine (a sympathomimetic vasoconstrictor). The effects of pH were investigated on vessel tone and responses to bupivacaine, methanandamide or zinc chloride. Bupivacaine and methanandamide (>10 µM) resulted in increased artery tone, with similar effects seen in conduit and resistance vessels. Zinc had no effect, possibly reflecting an inhibitory action on calcium channels. In the presence of endothelial blockers, methanandamide (100 µM) still resulted in an increase in artery tone, implying an action on smooth muscle. The application of nifedipine resulted in the inhibition of the response seen with bupivacaine (100 µM), implying that voltage-gated calcium entry was involved. Changing the pH from 7.3 to 8.3 resulted in vasoconstriction, and a relaxation was seen in acidic conditions. This is opposite to the result expected for TASK channel modulation, but may reflect the multiple effects of pH on smooth muscle. The contractions seen with bupivacaine and methanandamide were increased at pH 8.3 but inhibited at pH 6.3, consistent with an effect on TASK channels. Responses to bupivacaine and methanandamide were, however, very small, suggesting that currents produced by TASK channels may not be a major factor in contracting intrapulmonary arteries, but may still have a minor role.

Lowland calcareous grassland in the UK is a priority habitat designated under the UK Biodiversity Action Plan. Calcareous grasslands used to be common in north-western Europe and were utilized for grazing livestock such as sheep and cows. Many calcareous grasslands in England have been either agriculturally ‘improved’ through the addition of fertilizer and herbicides to increase productivity or have been ploughed up to make way for arable production, which has led to a dramatic decrease in the area of calcareous grassland. Minchinhampton Common is an area of lowland calcareous grassland located within the English county of Gloucestershire. In 1889, a golf course was laid out on the common for the use and enjoyment of local people. The first objective of this project was to investigate whether the presence of the golf course on Minchinhampton Common and associated golf-course management activities have had an effect on the composition and character of the calcareous grassland. The second objective was to investigate whether abandoned golf-course features on Minchinhampton Common, such as old fairways and old greens can recover to resemble undisturbed calcareous grassland. Significant differences were found between the undisturbed calcareous grassland and the fairways, greens and pathways in terms of vegetation height, plant species composition, botanical diversity and soil characteristics. This demonstrates that the presence of the golf course and the management carried out to maintain it has had an effect on the composition and character of the calcareous grassland. Significant differences were found when the fairways and greens were compared with the abandoned old fairways and old greens. This shows that after 15 years of abandonment the old fairways and old greens are no longer similar to the fairways and greens, but they are still different from the undisturbed calcareous grassland. It is hypothesized that to aid recovery, the abandoned features should be cut annually and the clippings removed. This will decrease the nutrient status of the soil and reduce the competitiveness of grasses, thus providing greater opportunities for the establishment of forb species typical of nutrient poor calcareous grasslands in north-western Europe.

Hepatitis C virus (HCV) is a worldwide pandemic, chronically affecting over 170 million people worldwide. It is a major risk factor for the development of hepatocellular carcinoma (HCC) and there is increasing experimental evidence to suggest that the virus plays a direct role in neoplastic transformation. The purpose of this letter is to review the literature regarding two individual proteins of HCV, namely NS5A and core, and their role in the pathogenesis of HCC through perturbations of cellular pathways, in addition to their immunopathological effects of chronic inflammation. A systematic search of MEDLINE in addition to manual searches of citations in key papers was employed to identify relevant studies. There is overwhelming evidence suggesting the direct and indirect roles HCV plays in the pathogenesis of HCC. Recent progress in our understanding of the pathophysiology of HCV coupled with advances in in vitro models will ensure that positive strides are made in the treatment and management of this potentially fatal virus.

Homogenates of salivary glands from Locusta migratoria possess phenoloxidase (PO) activity. This study investigates the activation of prophenoloxidase (PPO) in these glands in vitro . When freshly dissected salivary glands from L. migratoria are incubated with the immunogen laminarin, and then homogenized, a ∼4-fold increase in PO activity (expressed as a percentage of the total PO) can be measured within 20 min. Addition of laminarin to the incubation medium is best made prior to addition of salivary gland tissue, because when laminarin is added 10 min after the addition of tissue, the response to laminarin is reduced by ∼50%. When salivary glands are incubated in Ca2+-free Ringer, the response to laminarin cannot be demonstrated. Addition of a calcium ionophore to the incubation in normal Ringer does not initiate a response on its own, but does augment the response to laminarin. Addition of phorbol ester to an incubation containing normal Ringer has no effect on PO activity, and does not augment the response to laminarin. In contrast, addition of okadaic acid to normal Ringer has no effect on its own, but does augment the response to laminarin. Activation of PPO in response to laminarin is therefore calcium-dependant, possibly involving an influx of extracellular Ca2+, and modulated by protein phosphatases. Future work should aim to clarify the function of salivary glands in the immune defence of the locust and to investigate the exact source of the PO associated with the glands.

Somitogenesis is responsible for production of the segmented body plan typical of vertebrate embryos. The somites are blocks of mesoderm, produced by this process, that give rise to the vertebrae and ribs, the dermis of the skin and all the skeletal muscle of the body. Many genes that regulate somitogenesis have been identified in chick and mouse, whereas considerably fewer are known in Xenopus laevis. The expression of Hairy/Enhancer of split-related genes is known to cycle during somitogenesis and provides a mechanism for the regular formation of somites. In this project, in situ hybridizations were carried out on bowline, Thylacine1, Enhancer of split-related-1 (ESR1), ESR2 and ESR-5 in order to study their expression in relation to somitogenesis. All genes were found to be expressed during somitogenesis, even as early on as late gastrula stages in some cases. In addition, the expression of ESR2 is shown to be oscillating in the presegmented mesoderm of neurula and early-tailbud embryos. This study has identified ESR2 as the second known gene (after esr9) to show periodic oscillations of gene expression which can be considered as cycling during somitogenesis in X. laevis.

Woodland ground flora species Geranium robertianum, Prunella vulgaris and Deschampsia caespitosa were grown in greenhouse conditions under various light regimes (100%, 20% and 5% of ambient summer light) and were misted weekly with solutions of ammonium nitrate to simulate increased atmospheric wet and dry deposition of nitrogen (N) due to pollution at 0, 15 and 30 kg ha−1 year−1 concentrations. In the last 5 weeks of the study, the photosynthetic rate of G. robertianum was measured weekly. At the end of the 10-week-treatment period, the plants were harvested and growth was recorded using various measurable growth parameters. Growth of the plants and photosynthetic rate of G. robertianum were found to be primarily dependent on light availability, where reduced light levels showed a decrease in overall plant growth, indicating the importance of light in woodlands. N was not found to have an effect on the growth of the plants and thus questions arise over the calculations of critical loads of N deposition for woodland habitats. Five interactions were noted where increased N led to a significant reduction in growth at 20% light, yet a significant increase in growth at 100% light. These interactions were mainly noted for P. vulgaris, which could be explained by relatively large differences between its Ellenberg values for light and N, reflecting a preference for high light conditions and fairly infertile soils. G. robertianum was least affected by a reduction in light, reflecting its preference for semi-shaded conditions.

Leishmania are obligate intracellular vector-borne parasites that cause significant morbidity and mortality in many countries worldwide. There are several species of the parasite which vary according to geographical location and cause a variety of clinical syndromes ranging from self-limiting cutaneous lesions to potentially fatal infection of the viscera. The disease manifested is dependent on both the species of the parasite and the immune response of the host. Depending on the species of the parasite, resistance to infection is generally associated with a T-helper-1 immune response that activates macrophages to kill intracellular Leishmania in a nitric oxide-dependent manner. Conversely, disease progression is generally associated with a T-helper-2 response that activates humoral immunity. Chemotherapeutic treatments for leishmaniasis exist but are expensive, toxic and ineffective against resistant strains. A vaccine against leishmaniasis is feasible since most individuals that were once infected become resistant to clinical infection when later exposed. However, despite the wealth of information regarding the genetics of the parasite and the experimental immunology of the disease, there is currently no vaccine against Leishmania . A multitude of vaccine strategies have been pursued including the use of killed and genetically modified parasites. Immunization with naked plasmid DNA encoding Leishmania antigens represents a new approach to a Leishmania vaccine and confers several advantages over the more traditional vaccination methods. In order to develop an effective vaccine against leishmaniasis, it is important to understand the mechanisms of the immune response to Leishmania infection. This review discusses such immune mechanisms in detail and also explores several of the Leishmania vaccination strategies employed to date, with particular emphasis on DNA vaccines.

This work explores the role of the thiol-oxidoreductase ERp57 in the post-translational oxidative folding of the low-density lipoprotein receptor (LDL-R), a cell-surface glycoprotein responsible for the uptake of cholesterol from plasma. The LDL-R provides a general model to analyse oxidative folding of multi-domain proteins in the endoplasmic reticulum; yet its folding pathway is also of specific interest as a high proportion of mutations in disulphide-rich domains of the protein are evident in familial hypercholesterolemia. Previous studies have suggested that the LDL-R forms a set of distinct non-native disulphide intermediates during folding, which are extensively isomerized prior to secretion of the native conformer. In addition, ERp57 has been suggested to be predominantly reduced in vivo and to form a mixed disulphide with the LDL-R. In this study, the LDL-R was expressed in both wild-type cells and those lacking the thiol-oxidoreductase ERp57 under conditions that prevent disulphide formation. The protein was then allowed to fold under oxidizing conditions, and samples taken at various timepoints. The electrophoretic mobility of folding intermediates from knock-out cells was compared with that of wild-type cells. The results show that dissimilar disulphide intermediates form between the two cell types, particularly during early stages of folding. A mutant form of ERp57, able to form but unable to resolve mixed disulphides, was also found to form mixed disulphides with the LDL-R. The results signify the requirement for ERp57 in oxidative folding of the LDL-R and also suggest that non-native disulphide intermediates may be central to the process of multi-domain protein folding.

The process of introducing drugs into cells has always proved a major challenge for research scientists and for the pharmaceutical industry. The cell membrane is selectively permeable and supports no generic mechanism for their uptake. A drug must be either highly lipophilic or very small to stand a chance of cellular internalization. These restrictions mean that the repertoire of possible drug molecules is limited. Similarly, novel therapeutic approaches such as gene and protein therapy also have limited potential due to the cell-impermeable nature of peptides and oligonucleotides. The existing methods for delivery of macromolecules, such as viral vectors and membrane perturbation techniques, can result in high toxicity, immunogenicity and low delivery yield. However, in 1988 the remarkable ability of a peptide to traverse a cell's plasma membrane independent of a membrane receptor was revealed. Known as Tat, the transcription activator of the human immunodeficiency virus type 1 (HIV-1) viral genome was shown to enter cells in a non-toxic and highly efficient manner. In light of such properties Tat became known as the first ‘cell-penetrating peptide’ (CPP). CPPs have demonstrated themselves to be capable of delivering biologically active cargo to the cell interior and the vehicular capabilities of CPPs have already been harnessed for use as laboratory tools. However, it is believed that their true potential lies within the field of therapeutics. Attached to a CPP, therapeutic cargo could be delivered to an intracellular target, thus overcoming the entry restrictions set by the plasma membrane. Since the discovery of Tat, the number of known peptides with cell-penetrating capabilities has grown and in 2003, the first CPP-based drug reached phase II clinical trials. This review discusses the controversial mechanism of entry employed by CPPs, their potential applications in vitro and in vivo , and the ways in which CPP properties have been optimized to maximize their potential as future therapeutics.

Reduced quantities of dead wood in managed forests have resulted in a reduction in the abundance and diversity of saproxylic invertebrates to the extent that many are now considered red list species. To mitigate against this loss, one conservation measure is the provision of dead wood, in the form of piles of chopped logs, i.e. 'woodstacks'. The heterogeneity and volume of dead wood habitat is considered to be an important component of habitat suitability. However, the value of different woodstack types to invertebrate conservation has rarely been quantified and there is little consensus on how to best to survey the invertebrate fauna of woodstacks. This study used both sticky traps and pitfall traps to sample the invertebrate fauna of three types of sycamore woodstack. Woodstacks were made from 10 logs, 20 logs and 10 scorched logs plus a control woodstack made of unplasticised polyvinyl chloride (uPVC) plastic piping and observed over a 4-week period. A total of 1446 invertebrates from 16 orders, including 127 Coleoptera, were caught during the sampling period. A generalized linear model was used to analyse invertebrate abundance between woodstack and between trap types, and diversity was determined using Shannon diversity indices and analysed using a two-way Analysis of Variance (ANOVA). The woodstack type had no effect on the abundance of invertebrates. However, Shannon diversity was highest on the scorched woodstacks, with little difference between the 10 and 20log stacks and the control uPVC woodstacks. However, closer inspection of orders revealed the uPVC woodstacks to have the lowest abundance and diversity of Coleoptera. This study suggests that constructing woodstacks can provide suitable habitat for a variety of invertebrates. However, these invertebrates may have simply used the structures for shelter and the true value with saproxylic invertebrates could not be measured in this 4-week study. To fully appreciate the conservation value of woodstacks will require longer term studies that examine how and when saproxylic invertebrates use dead and decaying wood.

Alzheimer's disease is a growing concern with no satisfactory current treatment solution. Contemporary stem cell research offers a new arena for development in this field. Transplantation of stem cells into the damaged brain brings hope of repair to damaged neurons. This appears to operate via a ‘bystander effect’ whereby neurotrophins secreted by the cells act as a neuroprotectant, rather than a cell replacement mechanism as some have postulated. Such treatments can slow or even reverse cognitive decline. Research into neural stem cell transplantation has shown reversal of cognitive decline in animal models of disease via the mechanism of brain-derived neurotrophic factor secretion. Studies using nerve growth factor secreting stem cells have showed promising results with cognitive decline reversed in animal models of the disease. A Phase 1 clinical trial also showed promising reversal of cognitive decline in human subjects using transplantation of nerve growth factor secreting fibroblasts. Mesenchymal stem cells have also shown promise, and results from human trials are awaited. Induced pluripotent stem cells have provided a successful model of human disease in vitro. Although early results from transplant studies are encouraging, a lot more research will be needed before these preliminary advances can be translated to therapies with a strong evidence base to be used in practice.

Preliminary phytochemical screening was carried out and in vitro antimicrobial activities of leaves and stem of Mimosa invisa Mart. against some clinical pathogens were tested using standard techniques. Significance was measured using Duncan’s multiple range test. The inhibitory actions of the leaf and stem extracts increased with concentration. The rates of inhibition of the two extracts were low and high against Salmonella typhi and Aspergillus flavus respectively. The phytochemicals present in the plant parts had antimicrobial properties and reveal that M. invisa may have potential in pharmaceutical applications.

The genus Crassula contains a number of highly adaptable species, which can inhabit a wide range of environments. This investigation aimed to examine whether there are any differences in the anatomical adaptations in relation to water availability of four species of Crassula: the New Zealand pygmy weed, Crassula helmsii (T Kirk) Cockayne (from an aquatic habitat); the fairy crassula: Crassula multicava Lemaire ssp. multicava (from a subtropical habitat); the jade plant, Crassula ovata (Miller) Druce; and the anteelplakkie, Crassula socialis Schönland (both from semi-arid habitats). Plants were grown in a greenhouse and the anatomical features of stems and leaves were examined using light microscopy. Plant material was sectioned by hand and sections were stained with Toluidine blue O. Cuticle thicknesses were measured by treating sections with Sudan black B. Stomatal and hydathode densities on leaves and stems were measured using epidermal peels. Two measures of leaf succulence were used: degree of succulence and succulence quotient. The aquatic species C. helmsii had significantly fewer features associated with conserving water, including the thinnest cuticles on the adaxial leaf (P < 0.001) and abaxial leaf (P < 0.001). In contrast, the semi-arid species C. ovata had significantly the highest hydathodes on adaxial leaf surfaces (P < 0.001). Crassula ovata also had significantly the highest degree of succulence (P < 0.001), while C. socialis had the highest succulence quotient. The subtropical species, C. multicava, had significantly the thickest cuticles on adaxial leaf (P < 0.001) and stem (P < 0.001). Crassula species from arid environments had significantly more water conserving anatomical features, such as reduced stomatal densities, than those from less arid environments. However, all species studied possessed varying degrees of similar anatomical features. These features make Crassula a highly adaptable genus able to inhabit a wide range of environments.

Heavy metals are naturally present in soils as trace elements but deposition from vehicle wear and tear increases concentrations found adjacent to highways and has been shown to disperse further in relation to traffic volume. The heavy metal cadmium (Cd), used in the manufacture of tyres, has toxic effects on some plant species, with soil acidity being a major factor in plant Cd uptake. In this study, levels of Cd in soil and root material from Calluna vulgaris were investigated along with soil pH on wet heather moorland in the Peak District National Park. In December 2009, samples were collected from 10 transects extending up to 125 m from a trunk road that has a daily vehicle use >23 000. The peat substrate of the study site was found to be highly acidic (mean pH ± S.D.: 3.44 ± 0.119). Reported Cd concentrations in peat core samples (50–200 mm depth) are within the UK rural soil distribution range (0.1–1.8 mg kg−1), but increase progressively up to 85 and 125 m on either side of the road probably assisted by the wind. Root samples from C. vulgaris showed a degree of Cd accumulation (mean ± S.D.: 17.78 µg g−1 ± 9.338) compared with normal concentrations in plants from unpolluted soils (0.1 µg g−1). Coupled with data from previous research, results from this study suggest that increased soil Cd concentrations could affect the competitive balance between C. vulgaris and other moorland plants such as Molinia caerulea. Advances in analytical techniques allowing a better understanding of plant responses to metal toxicity are also discussed.

Superoxide anions have been associated with many aspects of cardiovascular disease. Menadione is a superoxide anion donor that alters the heart's electrical and mechanical functions. The aim of this study was to demonstrate simultaneous changes in intracellular Ca2+ ([Ca2+]i) and mechanical activity in intact adult cardiac myocytes, and mechanical activity and electrical activity in isolated whole hearts in order to provide greater insight into the mechanisms associated with the detrimental effects of menadione on the myocardium. Isolated hearts from adult male Wistar rats (n = 11, 200–250 g) were Langendorff perfused at 38°C with a Krebs–Henseleit solution. A saline-filled balloon was placed in the left ventricle (LV) in order to measure diastolic and developed pressure. Monophasic action potentials were simultaneously recorded from the epicardial surface. External stimulation at 5 Hz and intrinsic pacing were used throughout a 10 min control period and 30 min exposure to 50 μM menadione. Single LV myocytes (n = 7 from n = 4 animals) were loaded with the Ca2+-indicator Fura4-AM, stimulated at 1 Hz and exposed to 50 μM menadione. Myocyte length was simultaneously measured with [Ca2+]i using a video edge detection system. In isolated hearts, exposure to menadione significantly decreased contractility and action potential duration (with a similar time course); intrinsic heart rate and rhythmicity. Diastolic pressure was significantly increased. In single adult myocytes, menadione caused a significant increase in diastolic [Ca2+]i and a decrease in resting cell length and led to spontaneous release of [Ca2+]i. We conclude that the effects of menadione upon electrical and mechanical activity of the heart are at least in part a consequence of dysregulation of [Ca2+]i handling and the subsequent increase in diastolic [Ca2+] alterations in [Ca2+]i are consistent with the generation of delayed after depolarization arrhythmias.

Ageing is one of biology's longstanding enigmas—a problem that has perplexed both medical gerontologists and evolutionary biologists alike. One of the most prominent theories on the biochemical causes of ageing is the telomere-cell senescence theory. This theory proposes that ageing is due to the build up of telomere-induced senescent cells within the body. From an evolutionary standpoint, this system is thought to have evolved via antagonistic pleiotropy. Under this view, ageing is seen as a side effect of the telomere-cell senescence system, with the primary function of it being to defend against cancer. However, there are a number of problems with interpreting the system in this way, and several lines of evidence suggest that it was selected first and foremost to cause ageing. This logically entails the view that ageing is adaptive—an idea that is currently controversial.

Alzheimer's disease (AD) is characterized by neuronal loss and gradual cognitive impairment. AD is the leading cause of dementia worldwide and the incidence is increasing rapidly, with diagnoses expected to triple by the year 2050. Impaired cholinergic transmission is a major role player in the rapid deterioration associated with AD, primarily as a result of increased acetylcholinesterase (AChE) in the AD brain, responsible for reducing the amount of acetylcholine (ACh). Current drug therapies, known as AChE inhibitors (AChEIs), target this heightened level of AChE in an attempt to slow disease progression. AChEIs have only showed success in the treatment of mild to moderate AD symptoms, with the glutamate inhibitor memantine being the most common drug prescribed for the management of severe AD. As these drugs simply delay the onset of symptoms, the development of new therapies is key. As neurons are highly energy-demanding cells, they rely heavily on the functions of mitochondria, and any dysfunction affecting respiratory processes can be devastating and lead to the neuronal death characteristic of AD. Dysfunction in fission and fusion processes of mitochondria have been observed in early AD and are heavily involved in AD pathogenesis. Beta-amyloid (Aβ) is a neurotoxic protein formed in the AD brain as a result of inappropriate secretase activity and is one of the major hallmarks of the disease. Aβ has recently been discovered in the membranes of mitochondria, disabling many basic respiratory functions. Ongoing research is largely targeted at protecting mitochondria from damage caused by factors such as Aβ and oxidative stress. Antioxidants have been meticulously studied, and several generic antioxidants such as α-tocopherol have been found to significantly slow the rate of cognitive decline in both mild to moderate and severe AD. MitoQ is a mitochondria specific antioxidant which is able to enter mitochondria in an almost thousand fold greater concentration than is achieved by generic antioxidants. This enables protection against potentially devastating factors for mitochondria, such as lipid peroxidation, oxidative stress and Aβ neurotoxicity. This review further discusses mitochondrial therapies as well as other new treatments for AD.

Habitat fragmentation and road mortalities are major contributors towards declines in amphibian populations. This has seen the introduction of culverts, passages that run under roads and provide safe passage for amphibians. Research investigating the effects of rainfall upon amphibian culvert use is limited. This study, conducted at Frankfield Loch in Glasgow, assesses how time elapsed since rainfall influences migration behaviour and the use of culverts across four different species; common toads (Bufo bufo), common frogs (Rana temporaria and newts, a group composed of smooth newts (Lissotriton vulgaris) and palmate newts (Lissotriton helveticus). Analysis of images taken by a custom made, time lapse camera found that significantly fewer common toads (r = 0.148, n = 468, p = 0.001) and common frogs (r = −0.175, n = 106, p = 0.037) used the culvert as time since rainfall increased. This may have been caused by the culvert not maintaining wet enough conditions for amphibians. The study also found that more newts (r = 0.272, n = 92, p = 0.004) and common toads (r = 0.531, n = 19, p = 0.010) were using the culvert to move away from Frankfield Loch as time since rainfall increased. An increase in juvenile newts was also observed as time since rainfall increased (r = 0.214, n = 92, p = 0.020). This may have been caused by a decrease in barometric pressure, which follows a decrease in rainfall, acting as a cue for migration and juvenile dispersal. The study recommends careful consideration of the design of each culvert, incorporating species-specific preferences and the requirements of juveniles. The study also suggests that where possible the culvert should be designed to hold water for longer.

Haemostasis is the prevention of blood fluidity in vertebrates and is the first stage of wound healing. Haematophagous animals use the blood of vertebrates as their sole source of nutrition and have evolved many salivary constituents to counteract the haemostatic response of their prey. These animals and their saliva have been studied for many years, with some applications in medicine. The purpose of this study is to compare the salivary constituents of leeches (Hirudinae), ticks (Argasidae and Ixodidae) and vampire bats (Desmodontinae) and to consider their evolutionary origin. Salivary constituents include plasminogen activators (PAs), anticoagulants (activated factor X, FXa; inhibitors), vasodilators, platelet aggregation inhibitors (PAgI) and thrombin inhibitors. The animals studied all tend to possess an anticoagulant and a form of apyrase (PAgI) to assist with blood feeding. Ticks and vampire bats have a form of PA but the leech does not. The vampire bat has a PAgI but no vasodilator. The animals studied are from taxonomically unrelated groups but exploit similar mechanisms of action to facilitate their haematophagy. Given that the haematophagous lifestyle of these animals developed much later than their common ancestors, we conclude that their mechanisms for haematophagy have arisen by convergent evolution. Some molecules, e.g. serine proteases found in invertebrate saliva, are probably derived from a common ancestral gene. The possible paths that have led to evolution of vampire bat salivary components are considered. Further research into the homology of these salivary constituents is required to give insight into how these animals adapted to haematophagy and their further therapeutic potential.

The display of the disturbance hiss by the Madagascar Hissing Cockroach (Gromphadorhina portentosa) is considered to be an anti-predatory response despite there being little direct evidence linking the hiss with survival. Many studies have investigated the roles of the aggression and courtship hisses, displayed in this social species, but few have considered the role of the disturbance hiss. This study looked at the stimulus for the disturbance hiss response by placing unfamiliar individuals into different social contexts. A total of 10 male and 10 female G. portentosa were kept separately before being placed into four different social situations for 5 min at a time. The individuals were placed into an established colony of all females, an established colony of all males and an established colony of mixed sex G. portentosa. The subjects were also placed in the presence of a predator, an Emperor Scorpion (Pandinus imperator Koch). All interactions and hisses were recorded both by video and on a sound-recording device. There was a highly significant difference in the setting in which the disturbance hiss was shown and a highly significant difference in the display rates of the disturbance hiss between the sexes in general, with most displays of the disturbance hiss being when introduced to a mixed sex colony. The findings suggest that the role of the disturbance hiss is not an anti-predatory response when presented with a predator of limited auditory senses. Further study into the behavioural ecology of this species is recommended to understand the range of anti-predatory responses used by this species when presented with different predators. It was also found that there is some social context for the display of the disturbance hiss which warrants further study.

High incidence of resistance to pharmaceutical antibiotics among microbes in hospital environments prompts the search for alternative sources of anti-microbial chemicals. A largely underexploited resource in this regard is plants used in traditional Chinese medicine (TCM). In this investigation, anti-microbial properties of water extracts of two herbs used in TCM—Scutellaria baicalensis Georgi (Huang Qin) and Coptis chinensis Franch (Huang Lian)—against Escherichia coli B, coagulase-negative staphylococcus and Saccharomyces cerevisiae were examined using the disc diffusion method with water as a negative control and vancomycin as the positive control for coagulase-negative staphylococcus. Coptis chinensis appeared more potent than S. baicalensis against the three microbes used in the main experiments. Against E. coli B, the mean width and standard error of the kill zone was 3.9 ± 0.6 and 13.3 ± 0.7 mm for S. baicalensis and C. chinensis, respectively. Against coagulase-negative staphylococcus, the mean kill zone widths were 6.6 ± 1.1 and 11.0 ± 1.0 mm for S. baicalensis and C. chinensis, respectively. Against S. cerevisiae, the mean kill zone widths were 8.4 ± 1.0 and 12.6 ± 1.4 mm for S. baicalensis and C. chinensis, respectively. When compared with the positive control, C. chinensis was comparable in effect to vancomycin against coagulase-negative staphylococcus, whereas S. baicalensis was less effective than vancomycin. Further experiments investigated the use of herbs in combination and minimum inhibitory concentration. A limited number of further tests were conducted with other bacteria; E. coli 8879 (NCIMB 8879), Staphylococcus aureus (NCIMB 9518), Micrococcus luteus and Bacillus megaterium; both herbs killed all of the other bacteria, but C. chinensis appeared more potent than S. baicalensis. Diffusion disc technique provided a useful method to evaluate the anti-microbial effects of the two herbs, both of which showed promise as new anti-microbial agents.

The main line of treatment for chronic wounds is the application of an appropriate dressing. Dressings can be used to reduce odour and pain, maintain a moist healing environment, remove excessive exudate and prevent clinical infection. Antimicrobial compounds such as silver, honey and iodine have been in use for millennia. The discovery of antibiotics in the early 20th century greatly reduced the routine usage of such compounds. More recently, there has been renewed interest in these compounds, with manufacturers adding these to dressings to provide greater antimicrobial action and aid the healing process. Much of the published literature on the antimicrobial properties of silver, honey and iodine-containing dressings is contradictory, with varying degrees of efficacy reported. This study aimed to independently compare the in vitro antimicrobial activity of a wide variety of dressings against common wound pathogens; Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa, in order to provide further evidence and aid dressing selection. Although no significant differences were reported between honey, iodine and silver; a significant difference was observed between the individual dressings, indicating that determination of bacterial species present within a wound can aid clinical staff in the selection of the most appropriate dressing.

Cleome ciliata Schum. & Thonn. of the family Cleomaceae, is an annual herb. Phytochemical screening was carried out and the in vitro antimicrobial activities of leaf, stem and root extracts of C. ciliata were assessed using standard techniques. Duncan’s multiple range test was used to assess the significance of the results. The highest concentration of flavonoids (1.83 ± 0.04 mg/100 g), phenols (0.65 ± 0.00 mg/100 g) and terpenoids (1.93 ± 0.05 mg/100 g) was found in the leaf, stem and root respectively. Extracts of all the plant parts exhibited inhibitory activity against all test bacterial and fungal pathogens that are dose-dependent while the antagonistic effects of the leaf and root extracts were higher. The leaf extract showed the highest inhibition of Klebsiella pneumoniae, Streptococcus pneumoniae, Staphylococcus aureus, Salmonella typhi, Pseudomonas aeruginosa, Rhizopus stolonifer and Fusarium oxysporum; the root extract showed the highest inhibitory activity against K. pneumoniae and Penicillium chrysogenum while the three extracts were least effective against Escherichia coli, Shigella sonnei and Aspergillus niger. The study demonstrated that C. ciliata contains phytochemicals with antimicrobial properties and hence, its potential in antibacterial and antifungal drug development.

Diets rich in fruit and vegetables have long been associated with reduced risk of chronic disease. Antioxidant components of fruit and vegetables have recently generated great interest in scientific research. However, few studies have explored antioxidants in food after cooking. Cooking may alter antioxidant properties by initiating destruction, release or transformation of antioxidant food components. This study has investigated the effects of boiling and microwaving on the antioxidant properties of green broccoli and purple-sprouting broccoli. Antioxidant activities of the broccoli extracts were estimated using the 2,2-diphenyl-1-picrylhydrazyl radical scavenging method, vitamin C and phenols were estimated with the Folin-Ciocalteu reagent, flavonoids were evaluated using colorimetric methods and anthocyanins were determined by a pH differential method. Results showed antioxidant components of cooked broccoli to be quite different from uncooked broccoli. The antioxidant content of broccoli was retained and/or enhanced more after microwaving than after boiling. Cooking in water caused a leaching effect of antioxidants, and this increased with cooking time. Purple-sprouting broccoli was found to contain higher contents of antioxidant compounds compared with green broccoli, but tended to show higher sensitivity to cooking treatments. Cooking methods should be carefully considered in current dietary recommendations.

Whilst plastids are fundamental to many aspects of plant biology and the production of enhanced crop cultivars, research into the dynamics of non-green plastids has remained somewhat disregarded by the scientific community compared to chloroplasts. They are equally pivotal to normal plant development however, and are now increasingly becoming the focus of research made possible by genetic manipulation and reporter gene constructs. The total plastid content of all plant cells originates from small, undifferentiated plastids termed proplastids found within the meristematic regions of both root and shoot tissue. The cellular regulatory mechanisms controlling the development of plastids in young tissues are poorly understood, especially in the case of non-green plastids in roots. This investigation consequently aimed to elucidate the differences in plastid content, morphology and subcellular localization within epidermal cells derived from the root and shoot apical meristems (RAM and SAM respectively) of Arabidopsis thaliana. Quantification of non-green plastids was facilitated via the use of confocal laser scanning microscopy in conjunction with the expression of plastid-targeted green fluorescent protein driven by a constitutive promoter. Characterization of early seedling development and tissue diversification was also achieved by assessing epidermal cell size relative to developmental progression, ultimately facilitating comparative analyses of plastid dynamics on both a temporal and tissue-varietal basis. The number of plastids in epidermal cells within RAM-derived tissue was shown to increase across regions of cell division before being regulated throughout subsequent zones of elongation and maturing root tissue. In contrast, epidermal cells of the hypocotyl exhibit a more generalized increase in plastid number and less strict maintenance of cell plan area coverage during tissue expansion. The findings presented here suggest the functioning of distinct mechanisms regulating plastid division and growth in relation to cell size within shoot and root apical meristem-derived tissues.

Targeting tumour necrosis factor (TNF)-related apoptosis-inducing ligand (TRAIL), a mediator of apoptosis (cell death) and death ligand belonging to the TNF superfamily, represents a promising approach in anti-cancer therapy due to its selectivity to target cancer cell populations yet not normal cells. However, resistance to TRAIL is a common occurrence in tumours, limiting the effects of TRAIL to a minority of TRAIL-sensitive tumours. Peptidylarginine deiminase 4 (PAD4) is a Ca2+-dependent enzyme catalysing the post-translational conversion of arginine residues to citrulline within histones (citrullination), implicated in the epigenetic modulation of gene expression, with a potential role in tumourigenesis. This study aimed to determine whether the PAD4 inhibitor F-amidine may sensitize tumour cells to TRAIL-induced apoptosis. Expression of PAD4 mRNA was assessed in a panel of 18 cancer cell lines via real-time qRT-PCR to determine PAD4 sensitive cell lines. Prostate (LNCaP), breast (MCF-7), malignant glioma (U87-MG) and acute myeloid leukaemic (HL-60) cell lines were challenged with F-amidine in the presence or absence of death receptor 5 (DR5) agonists and nuclear morphology assessed via Hoechst 33342 staining. PAD4 mRNA expression was detected in 11 cancer cell lines from breast, prostate, leukaemic, glioma, neuroblastoma, myeloma, hepatocellular carcinoma and pluripotent embryonal carcinoma origin. F-amidine synergistically and significantly enhanced TRAIL responses within the PAD4 expressing TRAIL-resistant U87-MG cell line. PAD4 expressing TRAIL-sensitive HL-60 and resistant MCF-7 cell lines were not significantly sensitized to TRAIL-induced apoptosis. Significant synergistic TRAIL responses were observed in the TRAIL-resistant and PAD4 mRNA-negative LNCaP cell line, revealing that F-amidine may also potentiate TRAIL responses independent of PAD4 inhibition. Overall, this study presents some of the first evidence that PAD inhibitors may possess roles as novel TRAIL sensitizers in epigenetic anti-cancer therapy, potentially independent of PAD4 inhibition.

Type 1 diabetes mellitus (T1DM) is a chronic life-threatening condition whose incidence in the UK has doubled every 20 years since 1945 (Diabetes UK, 2010). Whilst intensive insulin therapy has been shown to reduce the incidence of long-term vascular complications in T1DM patients, it has also been shown to increase the risk of severe hypoglycaemia by 3-fold. Clinical islet transplantation has progressed considerably over the past decade, yet issues regarding the toxic effects of immunosuppression drugs and the paucity of pancreatic donor supplies remain. To provide an effective long-term therapy for heightened glycaemic control, many studies are investigating the potential of bioartificial islet encapsulation strategies and artificial bihormonal closed-loop systems. Following consideration of the basis of pancreatic transplantation, this article takes an in-depth look at both the benefits and limitations of bioartificial and artificial therapies and compares their potential in terms of providing an effective long-term solution to patients suffering with T1DM.

Up-frameshift protein 1 (Upf1) is a multidomain RNA helicase that is conserved from yeast to humans. Upf1 is critical for nonsense-mediated decay (NMD), a quality control mechanism that detects and eliminates aberrant transcripts harbouring a premature termination codon (PTC) and thus plays an important role in maintaining the fidelity of gene expression. Additionally, Upf1 is implicated in a broad range of cellular responses from chromosome maintenance to mRNA degradation and translational repression. Recent findings show that Upf1 also triggers 3′ end mRNA tagging, the addition of non-templated pyrimidines (C/U) to the 3′ end of adenylated and non-adenylated (histone) mRNAs. 3′ end tagging is seen as a general precursor of mRNA degradation and has been found to occur in fungi, plants and mammals. In Aspergillus nidulans, 3′ end tagging of normal and aberrant transcripts containing PTCs occurs in an Upf1-dependent manner. Intriguingly, tagging of transcripts harbouring PTCs is not essential for transcript degradation as the disruption of either of the two enzymes that mediate 3′ end RNA tagging, CutA and CutB results in decreased efficiency of ribosome dissociation from the PTC. However, the exact role of Upf1 and its functional domains in inducing tagging and ribosome dissociation remains unknown. Therefore, the aim of this work is to propose a model for the detailed mutational analysis of A. nidulans Upf1 in relation to its role in triggering 3′ end tagging and translation termination. From published data of mutation analysis, active site residues of the yeast and human Upf1 proteins have been identified and aligned to their A. nidulans homologue. Analysis of the structural organization of A. nidulans Upf1 reveals the presence of two major conserved domains and a number of putative actives site residues which may be crucial for 3′ end mRNA tagging, translational repression and ribosome termination. The importance of a greater understanding of the role of Upf1 in regulation of gene expression in A. nidulans, a model organism for Aspergillus species of medical and industrial importance, is discussed.

Chlamydia trachomatis, a member of the Chlamydiaceae, is the most common cause of bacterial sexually transmitted infections worldwide. The application of real-time polymerase chain reaction (PCR) in laboratory diagnostic testing for C. trachomatis is becoming increasingly popular. Modern approaches sometimes involve a combination of different test technologies for screening and confirmation; this indeed is a Clinical Pathology Accreditation (CPA) recommendation. Multiple real-time PCR platforms and assays are currently available, each of which comes with slight variation in their performances. Before incorporating any of these into routine clinical use, accuracy and reliability must be assessed. This study evaluated the performance characteristics of the Cepheid SmartCycler used in conjunction with the EuroClone Duplicareal time Dual Easy CT assay for the confirmation of Roche COBAS TaqMan positive tests by comparing results obtained by each method. Consecutive clinical C. trachomatis positive (n=67) and random negative (n=17) urogenital samples received at a general district hospital in the North East of England over a 6-month period were examined. Of the total 67 TaqMan-positive samples, 62 (92.5%) of them were also positive by the SmartCycler/EuroClone. There were 5 discrepancies in total (7.5%) and 17 samples were negative on both Roche TaqMan and SmartCycler/EuroClone. The sensitivity and specificity of the method were 92.5 and 100%, respectively. To further assess its specificity, the SmartCycler/EuroClone method was challenged with additional organisms and proved to possess the ability of avoiding false-positive results by correctly identifying these as C. trachomatis DNA negative. Finally, it was found that confirmation of positive C. trachomatis by the SmartCycler/EuroClone method increases the turn around time of chlamydia investigation by 2-folds. In conclusion, the SmartCycler/EuroClone method gave good concordance with the established Roche TaqMan method and proved to be highly suitable for confirmation testing of C. trachomatis positive samples. The remarkable specificity and acceptable sensitivity also confirms its suitability and reliability for this purpose.

There is an urgent need to find the most cost-effective treatment to help manage the ‘epidemic of obesity’. This study examined the long-term efficacy of lifestyle, pharmaceutical and surgical interventions of reducing weight in obese patients by carrying out a meta-analysis of published studies. English language randomized controlled trials were identified from Pubmed and the Cochrane Library in March 2013 that examined interventions for a minimum of 1 year in adults aged 18–70 years. Trials were selected on the basis of a Jadad score of >2 for pharmaceutical interventions and >1 for surgical interventions. Exercise and diet-combined therapy was more effective in producing weight loss than diet alone (mean of 5.18 ± 3.37 kg vs. 3.54 ± 3.67 kg), with a mean difference of 1.26 kg with 95% confidence interval (CI): 0.35–2.17 kg). Bariatric surgery resulted in a mean of 16.82% more body weight lost compared with a control group (95% CI: 14.60–19.03%). With respect to drug therapies, patients treated with lorcaserin lost a mean of 3.23 kg (95% CI: 2.70 to 3.75 kg) more than placebo (or 3.00% at 95% CI: 3.41–2.59). In contrast, patients treated with orlistat only lost a mean of 2.85 kg more than placebo (95% CI: 2.49–3.20 kg), equivalent to 2.88% (95% CI: 2.43–3.33%). These results indicate that bariatric surgery is the most effective intervention at causing clinically significant long-term weight loss, for patients with a body mass index of >35 kg/m2. However, it is also associated with considerable risks. Further research is also needed to identify whether lorcaserin or orlistat have a greater effect in particular patient sub-groups and examine the long-term efficacy of other drugs currently used off label for weight loss.

This review charts the evolution of phytoremediation from its earliest beginnings, with the discovery of metal tolerant plants in the 16th century and metabolism of organic pollutants by plants in the 1940s. The rapid expansion of research in the early 1990s led to many crucial discoveries but failed to surmount the fundamental limitations that often impede commercial application of phytoremediation. It is argued that phytoremediation was saved from being forgotten by its evolution under the new term phytotechnology, or ‘the application of science and engineering to examine problems and provide solutions using plants’. This review explores the use of phytotechnology for ecological engineering using constructed wetlands and evapotranspiration caps as landfill covers. Finally, the transfer of phytotechnology to developing countries, where it has great potential to solve the growing problem of pollution, is examined. The development of phytotechnology can be perceived as an illustration of the modern evolution of scientific thought, from the traditional reductionist view to a wider holistic approach which takes into account the natural environment and our need to preserve it. It is hoped that the evolution of both will allow for increasing conservation of finite resources without sacrificing continued development.

Bacteriophage λ (lambda) infects Escherichia coli and induces a dramatically increased rate and altered profile of genetic recombination as part of the cycle of infection. The genetic recombination processes augment the host-encoded recombination proteins with phage-encoded recombination proteins, promoting particular recombination pathways. This review characterizes the protein machinery involved in the most important processes underlying λ-mediated genetic recombination.

Adaptation to hypoxia is essential to survival in most organisms; disruption of oxygen homeostasis is linked to the pathology of multiple diseases including neurodegeneration, ischaemic stroke and cancer. Hypoxia-inducible factor 1 (HIF-1) is a key transcription factor in the detection of oxygen depletion and in mediating the response to hypoxia to maintain cellular oxygen homeostasis. This study investigated hypoxia signalling in vivo using a Caenorhabditis elegans HIF-1 mutant model. The chemosensory behaviour of C. elegans was analysed through the use of chemosensory assays with a chemoattractant and a chemorepellent; the response was quantified by calculating the chemotaxis index of species. Chemosensory assays were used to analyse behavioural changes of C. elegans under oxic and hypoxic conditions and to analyse the effects of mood stabilizing drugs lithium chloride (LiCl) and valproic acid (VA). HIF-1 mutant C. elegans showed an impaired chemosensory response to a 48 h hypoxia exposure. Treatment with LiCl significantly rescued the chemosensory response of HIF-1 mutants under hypoxia, suggesting a protective effect. Treatment with VA decreased the chemosensory response of HIF-1 mutants with hypoxia exposure. Interestingly, VA also decreased the chemosensory response of wild-type species under oxic conditions, suggesting a mechanism of action independent of hypoxia.

Nuclear enriched abundant transcript 1 (NEAT1) is a long non-coding RNA with two isoforms. Both are expressed constitutively and have been shown to play a crucial structural role in the formation of paraspeckles. Paraspeckles are subnuclear bodies which retain certain mRNAs, preventing their translation in the cytoplasm, thereby silencing the corresponding genes. This study aimed to assess the effects of knocking down NEAT1 by RNA interference on the Burkitt's lymphoma cell line, BJAB. The results have shown that a targeted siRNA depletion of NEAT1 resulted in an increased number of cells displaying aberrant morphology, including the appearance of 'giant cells', multinucleated cells and cells with cytoplasmic vacuoles. Furthermore, NEAT1 down-regulation was accompanied with an increased level of apoptosis and decreased cell viability, assessed by acridine orange morphology staining, vital dye exclusion and (3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl) -2H-tetrazolium) assay. Taken together, the study strongly suggests that modulation of NEAT1 expression has a significant effect on the BJAB cell line. Such remarkable effects of changes of NEAT1 expression on the control of cell morphology reported here indicate the potential significance of this gene in the development and progression of cancer and highlight the importance of further investigation into the role of NEAT1 dysregulation in autoimmune disease and oncogenesis.

In 2005, Boyden et al. used the protein channelrhodopsin-2 to generate the first ever light-induced action potential, involving a single component device. Since then, an explosion of so-called ‘optogenetic’ research has occurred. This abundance of new discoveries is reviewed here in depth. First, methods of targeting optogenetic techniques are discussed in brief. Next, both optogenetic sensors, used for observing neural circuits, and single-component optogenetic effectors, used for manipulating neural circuits, are assessed. The discoveries that these new technologies have led to is presented, current limitations of the respective technologies are examined and directions of future research discussed.

Marine protected areas (MPAs) can be used to conserve parts of marine ecosystems, including fish stocks exploited by fisheries. Social acceptance of MPAs must be achieved if they are to function as effective management tools. Artisanal fishers operating around tropical coral reef areas were questioned in an attempt to investigate their acceptance and perceptions of MPAs. Fishers from two areas were surveyed: Koh Rong Island, Cambodia, where MPAs are a new concept to fishers, and Southern Leyte, the Philippines, where MPAs have been used in management for over 10 years. Fishers' opinions of MPAs from each study site were compared and variables affecting fishers' opinions of MPAs were also investigated at each site. Although small sample sizes of fishers were observed at each study site, results showed that the majority of fishers at each site accepted MPAs as a management tool. Cambodian fishers felt the state of marine resources had worsened in the past decade (with regards to the number of fish, the size of fish and the number of species present in their catch), whereas most Filipino fishers had noticed an opposite trend. Older Cambodian fishers had greater acceptance of MPAs; age did not affect Filipino fishers' acceptance, and did not affect any other opinions fishers had of MPAs at either site. Community-based management of MPAs was fishers' preference at both sites. The study shows evidence of MPA support in Cambodia, with mobile gear users being more willing to be involved in MPA management. Most Filipino fishers felt that their MPA improved their catches, although there was evidence of conflict between fishers since the MPA was implemented.

Rigorous and cost-effective methods are essential to efficiently assess wildlife populations and obtain accurate data to inform conservation and management decisions. In the UK, available data on terrestrial mammal species are distinctly lacking, many populations are in decline and survey methods are technically demanding and labour-intensive. There is, therefore, much need to investigate alternative methodologies to ensure that resource use is efficient and data are reliable. Camera-trapping presents a relatively new approach for surveying mammals, though in the UK, the extent to which camera traps have been used has not been quantified and their performance has not yet been compared relative to existing methods. This study uses biological parameters and economic and logistic costs to assess the efficiency and reliability of camera-trapping and transect-sampling during winter field trials. Tracks and sign surveys and sightings surveys were conducted simultaneously and where appropriate, investigated independently. In addition, a nationally-distributed questionnaire was used to investigate surveyor competence and identify temporal trends in method use in the UK. Field trials concluded that camera-trapping was the most labour-efficient method for producing a species inventory, and frequently recorded more species per sampling site than did transect-sampling. However, when the total sampling period was limited, species were encountered at a faster rate by the detection of tracks and signs than by the alternative methods investigated. The single density estimate derived from camera trap data was higher than that from transect-sampling, and no differences were observed within the three alpha diversity index estimates derived by each survey method. The questionnaire suggests that the reliability of species presence/absence data derived from tracks and signs surveys is probably compromised by surveyor confidence of species identification. A multi-evidence approach is, therefore, recommended for less-competent surveyors. Despite greater initial economic costs, it is advocated that camera-trapping may be an efficient, rigorous and cost-effective method for large-scale long-term monitoring programmes. Furthermore, data suggest that camera trap use will become increasingly frequent in the UK. More research is required to investigate the relationships between method efficiency and season, species density and habitat, and to assess the accuracy of species density estimates.

Pancreatic cancer is the seventh most common form of cancer-related death in the world, affecting hundreds of thousands of people worldwide every year. Treatment for this type of cancer is largely ineffective and future treatments are likely to involve targeting signalling pathways involved in the proliferation of pluripotent stem cells. There are a variety of signalling pathways involved in the pathogenesis of the disease, including Hedgehog (Hh) and nuclear factor-kappaB (NF-κB). Overexpression of Hh ligands or alterations in other areas of the Hh signalling pathway may lead to tumour formation. Inhibition of Hh ligands, Smoothened or Gli proteins, or up-regulation of Patched expression, could form the basis of new treatments. NF-κB is often active in pancreatic cancer cells and down-regulation of NF-κB activating molecules can inhibit tumour progression in cell culture studies. Clinical trials show some promising results in novel drugs. There is growing evidence to suggest the interaction between these two signalling pathways. NF-κB appears to play a role upstream of the Hh pathway. This article looks at the roles these pathways play in pancreatic cancer and explores current research into targeting them for treatment.

With a continuing increase in the prevalence of cancer, there is an increasing pressure to produce novel cancer therapies. The production of targeted cancer therapies could lead to the replacement of conventional cancer chemotherapy and, consequently, the minimization of the associated distressing side effects. This review addresses the process of restoring a mutant tumour suppressor protein, p53, in the apoptosis pathway as a potential therapeutic target for cancer therapy. Current literature highlights the small molecule PRIMA-1 as a particularly promising novel cancer therapy; however, there are currently many potential therapies being investigated; CP-31398 is another small molecule with potential anti-cancer effects. PRIMA-1 acts to restore the mutant p53 by modifying thiol groups in the core domains of the protein. Its success is well documented, with many studies in different cancer models proving its effectiveness. This, however, is not unanimous, with some questions being raised about its efficacy and other aspects such as possible resistance mechanisms as well as potentially harmful degradation products. This said, PRIMA-1 has entered Stage II clinical trials and with more data collected on in vivo models and potential complications of the drug, it could ultimately provide an alternative to conventional cancer chemotherapy. This could therefore help to prevent cancer patients suffering the displeasing side effects with which it is associated.

Research into the origins of the first protocell is of a multidisciplinary nature. It draws evidence from what we know about the Earth’s early atmosphere and environment, and about the most ancient features of the cell’s structure and composition. Such data provides the input for the hypothesis generation and experimental reconstruction necessary to mimic steps in the formation of the first protocell. While research into the origins of the first protocell is condemned to focus upon laboratory experiments, it should be guided by a detailed study of real evidence pertaining to the environment on Earth 4 billion years ago. In this review, we take stock of the research that has been performed to date across the main disciplines of earth sciences, biochemistry, and molecular biology. We seek to identify the progress made in laying down a sequence for the events that led up to the first protocell. We also assess the strengths and weaknesses of the experimental designs and suggest some future approaches. While the field has made many important advances, from the original Stanley Miller experiment establishing ‘life from chemistry’ products such as amino acids, through to Deamer’s findings on fatty acid membranes and Szostack’s work on lipids, there is still a long and challenging journey ahead to understand how cellular life began. The experiments required to make more rapid progress in the field will likely be more elaborate, costly, and time consuming.

Native to Southern Africa, Lagarosiphon major is a submerged macrophyte that is recognized as a problematic, invasive non-native species in many countries including the UK. It is widely sold and promoted through the aquarium and water garden industry as an ‘efficient oxygenator’ for freshwater systems, irrespective of the absence of evidence to support this statement and evidence of its adverse ecological and economic impacts. A key concern, relating to its rapid growth rate and high fresh weight density, is that L. major can impose self-shading and limitation of photosynthetic and respiratory activity, causing it to consume more oxygen than it produces. Low dissolved oxygen (DO) conditions typify diminished water quality and seriously limit oxygen-dependent organisms. We measured over several months the DO, fresh weight and associated pond life abundances of L. major and a comparable UK-native macrophyte, Ceratophyllum demersum, established in small-pond conditions to determine which species best maintained a healthy freshwater environment. Both the time from establishment and species had significant effects on DO concentrations and pond life abundance; L. major produced the least amount of oxygen over time and had significantly less associated pond life compared to the native plant. L. major also increased significantly in overall fresh weight compared to C. demersum, indicating the higher invasive ability of the non-native species. In conclusion, our results suggest that L. major is not as good an oxygenator as C. demersum and that this native species should be promoted through the aquarium and water garden trades as an efficient oxygenator that improves water quality and habitat conditions over time.

Pain is a distressing physical and emotional experience associated with actual or potential tissue injury, or an experience described in terms of such injury. The primary function of nociceptors, such as some dorsal root ganglion (DRG) neurons, is to transduce noxious sensory modalities, e.g. mechanical pressure, cold and heat, into electrical impulses and to transmit these to processing centres in the central nervous system (CNS). Modality-specific pain pathways have been identified through in vivo deletion of voltage-gated Na⁺ channels in mouse DRG neurons. Deletion of Nav1.8 channels has been shown to result in loss of mechanosensory and cold-induced pain, but not-heat induced pain, whereas deletion of Nav1.7 channels has been seen to abolish responses to noxious heat and mechanical stimuli. The present review constitutes an attempt to elucidate the mechanisms through which voltage-gated Na⁺ channels are involved in modality-specific pain pathways. It has been found that Nav1.8 and Nav1.9 channels are resistant to slow inactivation upon cooling, maintaining activity even though channels on other sensory afferents may be inactivated. Nav1.7 channel activity is reported to be coupled to substance P release into the dorsal horn of dorsal root ganglion (DRG) neurons in heat-specific pain pathways. Recent research has also offered insight into the role of Nav1.7 and Nav1.9 mutations in pain-related conditions, e.g. inherited erythromelalgia and cold-aggravated pain, respectively, as these influence kinetic parameters, such as open state probability. Therefore, voltage-gated Na⁺ channels appear to be playing an important role in segregating modality-specific pain pathways. The identification of markers for mechanisms implicated in the activation of these pathways could potentially pave the way towards the development of more effective analgesics.

Association of ultra-high-molecular-weight polyethylene wear with osteolysis, leading to late aseptic loosening, has resulted in increased interest in alternative bearing prostheses. Alternative prostheses with cobalt-chrome bearing surfaces are now used more frequently, but research is needed to determine potential long-term biological effects of cobalt-chrome wear. The biological reactivity of cobalt-chrome particles may alter due to passivation and the storage of these particles in the laboratory; therefore, before any research can be carried out with these particles, an optimum storage protocol must be developed. This study aimed at determining any effects of the storage medium on the biological reactivity of cobalt-chrome wear. The viability of L929 cells was assessed following culture with clinically relevant cobalt-chrome particles stored in phosphate-buffered saline, in serum and dry at using condition the 3-[4, 5-Dimethylthiazol-2-yl]-2, 5-diphenyltetrazolium bromide assay. Storage of these cobalt-chrome nanoparticles (100 and 50μm3cell-1) in serum resulted in a significantly greater reduction in cell viability compared with dry stored particles at the same dose, indicating that the storage of cobalt-chrome wear influences the biological reactivity of the particles. Therefore, it is suggested that studies investigating effects of cobalt-chrome wear particles should store them in serum prior to use in laboratory studies, these particles display the highest level of cytotoxicity and are how the particles are presented in vivo.

Transverse sections (T/S) of the roots of Citrus aurantifolia (Christm.) Swingle, C. grandis Osbeck, C. limon (L.) Burm.f., C. paradisii Macf., C. reticulata Blanco and C. sinensis (L.) Osbeck were investigated using standard plant anatomical procedures. The pores of roots of all the species were oval in shape. The sizes of the pores found in C. sinensis were the lowest range (117–27 µm in length; 108–27 µm in width). The distributions of axial parenchyma were confluent parenchyma in Citrus aurantifolia, C. grandis, C. paradisii, C. reticulata and C. sinensis, whereas it was vasicentric aliform parenchyma in C. limon. Citrus limon, therefore, possessed an advanced feature which indicated that it evolved at a different rate compared with others. The study revealed anatomical characters of these Citrus species and hence shed light on their affinity. The characters of secondary wood, therefore, could be applied as additional characters by plant taxonomists in resolving the ongoing controversy in the taxonomy of Citrus.

Global biodiversity, and its associated ecosystem services, are threatened due to species extinctions. Reintroducing locally extinct species may be a partial solution to this problem. However, the success and possible consequences of any artificial reintroduction will depend on its ecological community, and the reaction of that community to the species’ extinction and reintroduction. Mathematical models can offer useful insights by identifying the key features of communities and reintroduced species most likely to result in successful reintroductions. Here we simulated extinctions and reintroductions for a range of theoretical food webs generated using an established bioenergetics model. This allows the probability of successful reintroductions to be quantified as a function of two important ecological factors: the connectance of the food web, and of the time between extinctions and reintroductions. Reintroduction success is measured across an ensemble of 1796 simulated communities, with connnectances of 0.05, 0.15 and 0.3, using three criteria: presence of the reintroduced species in the final community, unchanged species richness in the final community compared to the pre-extinction persistent community and the complete restoration of the community (including both species richness and equilibrium biomass distributions). Although only 12 reintroduced species fail to re-establish according to minimal criteria, the process of extinction and reintroduction frequently has a large effect on the community composition. Increasing time to reintroduction increases both the probability of species loss, and equilibrium biomass change in the community. Proportionally, these community-level impacts occur more frequently when the reintroduced species is a primary producer or top predator. These results indicate that ignoring broader measures of reintroduction success could seriously underestimate the impact of reintroductions on the ecological community. These quantitative results can be compared to empirical literature and may help reveal which factors are most important to the success of reintroductions.

Neurodegenerative disorders such as Huntington's, Alzheimer's, Parkinson's and prion diseases are progressive and without a cure. A common finding is one of misfolded protein aggregates, conventionally believed to underlie pathogenesis via a toxic gain of function. Recently, a potential contribution of loss of normal protein function has come under the spotlight. With a focus on huntingtin, the protein involved in Huntington's disease, this review examines the evidence for the conventional ‘gain of function’ model, before considering the hypothesis that a loss of function contributes to pathogenesis. In support of a primarily toxic gain of function are findings that huntingtin aggregates are neurotoxic in vitro. Additionally, aggregates of mutant huntingtin proteins have been detected prior to neuropathological changes, supporting a causal role. However, a dissociation between the neurons containing mutant huntingtin aggregates and those that are most vulnerable in Huntington's disease indicates the possibility of a contribution from a loss of protein function. Evidence suggests a neuroprotective role for huntingtin; loss of its functions could feasibly lead to neurodegeneration. An exclusive role of loss of function is contradicted by the finding that genetic ablation of huntingtin protein does not cause Huntington's disease, but a contribution from loss of function is supported by similarities between neuropathological and behavioural phenotypes in animal models of Huntington's Disease and those produced by loss of the normal functions of huntingtin. Perhaps, therefore, both loss and gain of function are necessary processes in Huntington's pathogenesis, with neither one sufficient to cause the disease alone. Review of the current evidence fails to elucidate an exact role for loss of function in Huntington's disease pathogenesis. More information is required on the extent to which depletion of the normal protein causes, rather than accompanies, disease. In the meantime, attempts at drug discovery should be mindful of the possibility of a contribution from loss of function when designing treatments and interpreting trial results.