Richard O. Jenkins's research while affiliated with De Montfort University and other places

Publications (100)

Article
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Organophosphates (OPs) are toxic chemicals produced by an esterification process and some other routes. They are the main components of herbicides, pesticides, and insecticides and are also widely used in the production of plastics and solvents. Acute or chronic exposure to OPs can manifest in various levels of toxicity to humans, animals, plants,...
Article
Full-text available
Clostridioides difficile spores were previously demonstrated to survive industrial laundering. Understanding interactions between heat, disinfectants and soiling (e.g. bodily fluids) affecting C. difficile spore survival could inform the optimization of healthcare laundry processes. Reducing spore attachment to linen could also enhance laundering e...
Article
Full-text available
The delayed effects of acute intoxication by organophosphates (OPs) are poorly understood, and the various experimental animal models often do not take into account species characteristics. The principal biochemical feature of rodents is the presence of carboxylesterase in blood plasma, which is a target for OPs and can greatly distort their specif...
Article
Full-text available
Exposure to As from drinking water and its impact on the health of the Bangladeshi population has received much attention. However, very little information is available regarding As exposure through consumption of fish, which is the main source of animal protein for the majority of Bangladeshis. In this study, concentrations of As, Cd, Pb, Mn Se an...
Article
Full-text available
Serum albumin possesses esterase and pseudo-esterase activities towards a number of endogenous and exogenous substrates, but the mechanism of interaction of various esters and other compounds with albumin is still unclear. In the present study, proton nuclear magnetic resonance (1H NMR) has been applied to the study of true esterase activity of alb...
Article
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Being one of the main proteins in the human body and many animal species, albumin plays a decisive role in the transport of various ions—electrically neutral and charged molecules—and in maintaining the colloidal osmotic pressure of the blood. Albumin is able to bind to almost all known drugs, as well as many nutraceuticals and toxic substances, la...
Article
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Intermittent fasting has been reported to be beneficial for individuals with type 2 diabetes mellitus (T2DM), which is being developed as a non-pharmacological therapy for the management of T2DM. The impact of Ramadan fasting, a type of intermittent fasting, in the management of diabetes has not been well investigated. This mini-review discusses th...
Article
Background: Ambient temperature is predicted to rise in Saudi Arabia, and how this will impact the health of its population has not been investigated. Saudi Arabia is one of the top ten countries with the highest prevalence of diabetes. The current study investigates the correlation between ambient temperature and HbA1c levels in a group of Saudis...
Chapter
Toxic and mechanistic properties of nutraceuticals are not as extensively studied as those of pharmaceuticals. Flow cytometry is among the most popular techniques to investigate the modes and mechanisms of cytotoxic action of chemical compounds, though flow cytometry methods are not suitable for online registration of rapid changes in cell volumes....
Chapter
Fatigue during exercise is defined as the inability to maintain the required level of strength and performance. Doping agents and manipulation of any kind are undesirable companions of professional and amateur sports. Nutraceuticals have advantages over medicines because they avoid side effects and naturally supplement the diet. In this chapter, ex...
Chapter
Organosulfur compounds (OSCs) are widely present in our bodies and the natural environment. There are two principal groups of vegetables that contain OSC with special properties. Garlic, onion, shallot, leek, and chives are well-known representatives of the Allium genus (family Amaryllidaceae), that contain S-alk(en)yl-l-cysteine sulfoxides. Cabbag...
Article
Full-text available
As a carrier of many biologically active compounds, blood is exposed to oxidants to a greater extent than the intracellular environment. Serum albumin plays a key role in antioxidant defence under both normal and oxidative stress conditions. This review evaluates data published in the literature and from our own research on the mechanisms of the en...
Article
Background Glycated haemoglobin (HbA1c) is the gold standard measurement in the screening, diagnosis and monitoring of diabetes mellitus. Saudi Arabia has a high prevalence of diabetes mellitus that is expected to rise, and the HbA1c test is commonly used in the screening, diagnosis and monitoring of diabetes. Objective his study aims to assess th...
Article
Full-text available
IntroductionThe impact of Ramadan fasting, a type of intermittent fasting, on the management of diabetes has not been well investigated. Physical activity, sleep duration, and time of sleep are susceptible to alterations during Ramadan due to the changes in the times and numbers of meals. This study compared physical activity and sleep patterns of...
Conference Paper
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Background: Physical activity is an important factor in the treatment and prevention of type 2 diabetes mellitus (T2DM). Reduction in HbA1c level, an important diabetes biomarker, was reported in patients who increased their daily physical activity. Although the ambient temperature was reported to be positively correlated to a negative impact on he...
Conference Paper
Full-text available
Background: Quantity and quality of sleep have been reported to be significant risk factors for obesity and development of metabolic disorders such as type 2 diabetes mellitus (T2DM). The relationship between diabetes and sleep quantity was reported to be U-shaped, which means increased or decreased sleeping hours can increase the risk of diabetes....
Conference Paper
Full-text available
Background: Unhealthy diet is one of the modifiable risk factors for developing type 2 diabetes mellitus (T2DM). Improvement in diet can be beneficial for countering diabetes. For example, HbA1c, an important biomarker for diabetes, can be reduced by 1.1% through only alteration in diet. Ramadan fasting has been reported to provide positive health...
Article
Background: Ambient temperature is predicted to rise in Saudi Arabia, and how this will impact the health of its population has not been investigated. Saudi Arabia is one of the top ten countries with the highest prevalence of diabetes. The current study investigates the correlation between ambient temperature and HbA1c levels in a group of Saudis...
Article
Full-text available
Second messenger nicotinic acid adenine dinucleotide phosphate (NAADP) triggers Ca2+ release via two-pore channels (TPCs) localized in endolysosomal vesicles. The aim of the present work is to evaluate the role of TPCs in the action of norepinephrine (NE), angiotensin II (AngII), vasopressin (AVP), and 5-hydroxytriptamine (5-HT) on free cytoplasmic...
Poster
Full-text available
The impact of the month of Ramadan on the annual variation in HbA1c levels in a Saudi population
Chapter
Nutraceuticals are derived from various natural sources such as medicinal plants, marine organisms, vegetables, and fruits. Most of them possess antioxidant or anti-inflammatory properties and are claimed to provide protection against many diseases if taken regularly. At the same time, toxicological studies of nutraceuticals have been limited, so t...
Article
Poisoning by organophosphates (OPs) takes one of the leading places in the total number of exotoxicoses. Detoxication of OPs at the first stage of the poison entering the body could be achieved with the help of DNA- or RNA-aptamers, which are able to bind poisons in the bloodstream. The aim of the research was to develop an approach to rational in...
Article
Objective To quantify the survival of Clostridium difficile spores on hospital bed sheets through the United Kingdom National Health System (UK NHS) healthcare laundry process (Health Technical Memorandum (HTM) 01-04) in vitro and on bed sheets from patients with C. difficile through the commercial laundry. Methods Clostridium difficile spores wer...
Article
Antibacterial efficacy of nanoscale silver, copper (II) oxide and zinc oxide were assessed against Pseudomonas aeruginosa and Staphylococcus aureus biofilms in solution and on surfaces. Using a Center for Disease Control biofilm reactor, minimum biofilm reduction concentrations, the coefficient of determination (R 2) and log(10) reductions were det...
Article
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Water hyacinth (Eichhornia crassipes) has been used for environmentally sustainable phytoremediation of water, though its use has been geographically restricted. For the first time we extend its geographical reach by investigating its potential for clean-up of water from a highly polluted British river (Nant-Y-Fendrod, a tributary of the River Tawe...
Article
Abstract Multivariate analysis of a heavy metal pollution survey of closed and active landfill precursors was carried out in order to compare environmental risk levels in relation to age, particle size and depth of the precursors. Landfill precursors (77) were collected and analyzed for 15 USEPA toxic heavy metals using ICP-MS. Heavy metals concent...
Article
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Endothelium is a community of endothelial cells (ECs), which line the blood and lymphatic vessels, thus forming an interface between the tissues and the blood or lympha. This strategic position of endothelium infers its indispensable functional role in controlling vasoregulation, haemostasis, and inflammation. The state of endothelium is simultaneo...
Article
Full-text available
The albumin molecule, in contrast to many other plasma proteins, is not covered with a carbohydrate moiety and can bind and transport various molecules of endogenous and exogenous origin. The enzymatic activity of albumin, the existence of which many scientists perceive skeptically, is much less studied. In toxicology, understanding the mechanistic...
Article
Full-text available
The elemental and chemical constituents of an active and a closed landfill were compared using Fourier transform-infrared (FTIR) spectroscopy, scanning electron microscope/energy-dispersive X-ray spectroscopy, and proximate analysis. The two landfills had similar major elemental constituents representing 96.5 and 98.4 % of elemental composition for...
Article
Glycosaminoglycans (GAGs) in the urine of Wistar rats, and on the surface of the epithelium and lamina propria of the bladder, were quantitatively assessed before and after acute intoxication with paraoxon or cyclophosphamide. Paraoxon was administered subcutaneously (s.c.) twice with an interval of 1 h to a final dose of 275 µg/kg; cyclophosphamid...
Article
Full-text available
The compositional trend and characteristics of active and closed landfill composites with depth was evaluated, in order to establish possible relationships between seasonal variations in moisture content, distribution of total organic carbon (TOC) and pH stability. A bulk system of composite classification was used. Both landfills had similar waste...
Article
Full-text available
Abstract: The compositional trend and characteristics of active and closed landfill composites with depth was evaluated, in order to establish possible relationships between seasonal variations in moisture content, distribution of total organic carbon (TOC) and pH stability. A bulk system of composite classification was used. Both landfills had sim...
Chapter
Fatigue during exercise is defined as the inability to maintain the required level of strength and performance. Doping agents and manipulation of any kind are undesirable companions of professional and amateur sports. Nutraceuticals have an advantage over medicines because they lack side effects and naturally supplement the diet. In this chapter, e...
Chapter
Toxic and mechanistic properties of nutraceuticals are not as extensively studied as those of pharmaceuticals. Flow cytometry is among the most popular techniques to investigate the modes and mechanisms of cytotoxic action of chemical compounds, although flow cytometry methods are not suitable for online registration of fast changes of cell volumes...
Chapter
Organosulfur compounds (OSC) are widely present in our bodies and the natural environment. There are two principal groups of vegetables that contain OSC with special properties. Garlic, onion, shallot, leek, and chives are well-known representatives of the Allium genus (family Amaryllidaceae) that contain S-alk(en)yl-l-cysteine sulfoxides. Cabbage,...
Article
In blood vessels, serotonin 5-HT2B receptors mainly mediate relaxation, although their activation by the selective agonist BW723C86 is known to exert contraction of aorta in deoxycorticosterone acetate (DOCA)-salt and N(omega)-nitro-L-arginine (L-NAME) hypertensive rats [Russel et al., 2002; Banes et al., 2003] and in mice with type 2 diabetes [Nel...
Article
Millions of people in Bangladesh are exposed to high concentration of the toxic element arsenic (As) through drinking water and consumption of foods. It has also been reported that Bangladeshis have a low intake of the essential element selenium (Se), which is known to be important as an antioxidant and has been suggested to counteract the toxicity...
Article
Full-text available
The volume of publications on the role of reactive oxygen species (ROS) in biological processes has been increasing exponentially over the last decades. ROS in large amounts clearly have detrimental effects on cell physiology, whereas low concentrations of ROS are permanently produced in cells and play a role as signaling molecules. An imbalance in...
Article
The relationship between arsenic (As) and selenium (Se) in the human body is poorly understood. We have investi-gated the concentrations of urinary As and Se in three ethnic groups (n = 63) in the United Kingdom and show that there is a positive correlation (r = 0.62, p < 0.001) between total concentrations of As and Se and that the ratio of these...
Article
Elevated exposure to arsenic has been suggested to be associated with atherosclerosis leading to cardiovascular disease (CVD). However, biochemical events underlying the arsenic-induced atherosclerosis have not yet been fully documented. The aim of this study was to investigate the associations of circulating molecules involved in atherosclerosis w...
Article
Unlabelled: Rice can easily accumulate arsenic (As) into its grain and is known to be the highest As-containing cereal. In addition, the As burden in rice may increase during its processing (such as when cooking using As-polluted water). The health risk posed by the presence of As in cooked rice depends on its release from the matrix along the dig...
Article
Two microplate spectroscopic methods for determination of organophosphates, based on inhibition of acetylcholinesterase (AChE) activity, were further improved and evaluated for determination of the chemical weapon agent Russian VX (RVX) in aqueous solutions. The linear range of the Hestrin method (74.8-1120 pM) was 3.1-fold wider than that of the E...
Article
Full-text available
Hundreds of millions of people world-wide are exposed to high concentrations of the toxic element arsenic (As) through drinking water and consumption of certain foods, especially rice. In this study Inductively Coupled Plasma Mass Spectroscopy (ICP-MS) was used to analyse rice from the greater Sylhet region of Bangladesh which has relatively lower...
Article
Several studies have reported increased skin lesions in betel quid (a mixture of Piper betel leaves, areca nut, tobacco/flavoured tobacco, lime) chewers compared to non-chewers, exposed to arsenic (As) contaminated drinking water in Bangladesh and India. The current study has determined As, cadmium (Cd) and lead (Pb) levels of betel quids and its c...
Article
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Rice is elevated in arsenic (As) compared to other staple grains. The Bangladeshi community living in the United Kingdom (UK) has a ca. 30-fold higher consumption of rice than white Caucasians. In order to assess the impact of this difference in rice consumption, urinary arsenicals of 49 volunteers in the UK (Bangladeshi n = 37; white Caucasians n...
Article
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A relationship between betel quid chewing in Bangladeshi populations and the development of skin lesions and tremor has been previously reported, for people exposed to high levels of arsenic (As) through drinking contaminated groundwater. Exposure to manganese (Mn) is also known to induce neurotoxicity and levels of Mn in Bangladeshi groundwater ar...
Article
Full-text available
Geophagy or earth-eating is common amongst some Bangladeshi women, especially those who are pregnant, both in Bangladesh and in the United Kingdom. A large proportion of the population in Bangladesh is already exposed to high concentrations of arsenic (As) and other toxic elements from drinking contaminated groundwater. Additional exposure to As an...
Article
Computer-aided learning software designed to illustrate the structure and replication of DNA, and the principles and applications of DNA sequencing and PCR is described. Tailoring the software to individual needs enhances its effective use over a wide range of higher education levels by students with disparate backgrounds. The computer-based librar...
Article
Full-text available
Two microplate spectroscopic methods for determination of organophosphates, based on inhibition of acetylcholinesterase activity, have been elaborated and evaluated for determination of the chemical weapon agent soman. The principal difference between the methods is that one measures reaction substrate concentration (elaborated from Hestrin), while...
Chapter
This title is not available to purchase from Royal Society of Chemistry. Please visit www.bioinorganic-chemistry.org/mils for title information. This volume, closely related to MILS-6, deals mainly with metal(loid)-alkyl derivatives but also with the rarer aryl compounds. Most of these (commonly toxic) compounds are formed in the environment by mi...
Article
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Measurement of the different physicochemical forms of metals and metalloids is a necessary pre-requisite for the detailed understanding of an element's interaction with environmental and biological systems. Such chemical speciation data is important in a range of areas, including toxicology, ecotoxicology, biogeochemistry, food safety and nutrition...
Chapter
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Fluoroorganic compounds attracted the attention of researchers nearly 70 years ago when among a large class of biologically inert chemicals, a group of very toxic compounds was revealed, having the general formula SO2FCOOR and the common name ‘‘fluoroacetate’’ (FA). The extreme toxicity of FA is determined by its similarity to acetate, which has a...
Chapter
This chapter describes the chemistry, analysis, toxicity, monitoring, and regulatory hygiene, and therapy of Russian VX nerve agent. One of the most abundant and most toxic chemical warfare agents in the chemical arsenals of the USA and Russia is VX and Russian VX respectively, whose development in the middle of the 20th century signified the peak...
Article
Full-text available
Rice has been demonstrated to be one of the major contributors to inorganic arsenic (i-As) intake in humans. However, little is known about rice products as additional source of i-As exposure. In this study, misos, syrups and amazake (a fermented sweet rice drink) produced from rice, barley and millet were analysed for total arsenic (t-As) and a su...
Article
Allergen-induced anaphylaxis has been suggested as a possible etiology for sudden infant death syndrome (SIDS). Some of the measures recommended for reducing the risk of allergen exposure also are recommended for reducing the risk of SIDS. The purpose of this study is to evaluate possible associations between dust-mite allergen (der p 1) levels wit...
Article
Full-text available
A study was conducted of acute intoxication of infant and adult Wistar rats with fluoroacetamide (FAA), an inhibitor of oxidative metabolism. FAA was administered orally to adult rats at 1/2 LD50 and subcutaneously to infant rats at LD100 or 1/10 LD50. Electrocardiogram (ECG), respiration and motor activity were registered for 7 days. Clinical anal...
Article
The use of high-performance liquid chromatography (HPLC) coupled to inductively coupled plasma mass spectrometry (ICP-MS) for the determination of methylmercury (MeHg+) in fish tissue and hair samples is described. Analysis of these sample types is required when carrying out biomonitoring studies to determine human dietary exposure to this toxic me...
Article
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A sensitive methodology for PCR detection of Staphylococcus aureus or Bordetella pertussis DNA within cot mattress polyurethane foam was developed. The assay's applicability was evaluated on polyurethane foam from used cot mattresses. S. aureus DNA was detected in 42% of mattresses of sudden infant death syndrome (SIDS) victims and 29% of compariso...
Article
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The construction and evaluation of a low cost, easily demountable interface to couple capillary gas chromatography to inductively coupled plasma mass spectrometry detection is described. Using this interface, the capillary column can be maintained at a high temperature through to the tip of the torch injector using a transfer line heated by a combi...
Article
Millions of people in some of the poorest regions of the world are exposed to high levels of arsenic through drinking contaminated water. It has been reported that development of cancer caused by arsenic exposure in such populations is dependent on dietary and nutritional factors which can modulate arsenic metabolism. Many people in arsenic exposed...
Article
Full-text available
A low-angle light scattering technique, which has been applied previously to studies of blood platelets and Ehrlich ascite tumor cells, revealed differences in the dynamics of necrotic and apoptotic red blood cell death. Under hypotonic loading or in ammonia medium, red blood cells (RBC) swelled to a critical size (diameter approximately 13 µm) pri...
Article
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Experiments were performed with rat liver mitochondria, Ehrlich ascite tumor cells (EATC) and cardiomyocytes, exposed to fluoroacetate (FA) or fluorocitrate (FC) in vitro. The effects of FA developed at much higher concentrations in comparison with FC and was dependent upon respiratory substrates: with pyruvate, FA induced a slow oxidation of pyrid...
Article
Full-text available
A novel procedure has been developed for determination of fluoroacetic acid (FAA) in water and biological samples. It involves ethylation of FAA with ethanol in the presence of sulfuric acid, solid-phase microextraction of the ethyl fluoroacetate formed, and subsequent analysis by GC-FID or by GC-MS in selected-ion-monitoring mode. The detection li...
Article
Very little is known about arsenic (As) metabolism in healthy populations that are not exposed to high concentrations of As in their food or water. Here we present a study with healthy volunteers from three different ethnic groups, residing in Leicester, UK, which reveals statistically significant differences in the levels of total As in urine and...
Article
Full-text available
In this review we discuss a range of spectroscopic techniques that are currently used for analysis of arsenic in human urine for understanding arsenic metabolism and toxicity, especially in relation to genetics/ethnicity, ingestion studies and exposure to arsenic through drinking water and diet. Spectroscopic techniques used for analysis of arsenic...
Article
Full-text available
Fluoroacetate (FA; CH2FCOOR) is highly toxic towards humans and other mammals through inhibition of the enzyme aconitase in the tricarboxylic acid cycle, caused by 'lethal synthesis' of an isomer of fluorocitrate (FC). FA is found in a range of plant species and their ingestion can cause the death of ruminant animals. Some fluorinated compounds --...
Article
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A new method for studying platelets based on low-angle light scattering has previously revealed that platelets taken from pregnant women with preeclampsia are hypersensitive to ADP, with aggregation developing at concentrations of 7–15 nmol l−1. The method has been applied to further studies in experimental toxicology and clinical pathology. Toxico...