[Show abstract][Hide abstract] ABSTRACT: Koumiss is a traditionally fermented mare’s milk described with health-promoting potentials for decades. However, only a few studies focused on the probiotic strains isolated from koumiss. In this study, we collected koumiss samples from Inner Mongolian pasturing area of China and selected a promising strain of Lactobacillus helveticus, isolate NS8, based on the survival abilities in gastrointestinal tract (GIT) and adhesion to intestinal endothelial cells in vitro. As the ability to positively modulate host immune response is a feature of increasing importance in measuring the probiotic potential of a bacterial strain, our study mainly focus on the immunomodulatory properties of L. helveticus NS8 by using in vivo and ex vivo analyses.
L. helveticus NS8 was identified by molecular-typing methods, both at genus and species levels. As a typical food niche-specific bacteria, NS8 showed a moderate survival ability in GIT environment in vitro. However, an excellent binding capacity to the human intestinal epithelial cells, along with significant autoaggregation and cell-surface hydrophobicity was observed. Additionally, the presence of S-layer protein was responsible for the cell surface properties of this strain. NS8 was found to be rather protective against TNBS (2,4,6-trinitrobenzene sulfonic acid)-induced murine colitis. In the meantime, co-culture with NS8 induced an increased level of secretion of anti-inflammatory cytokine IL-10 in peripheral blood mono-nuclear cells (PBMCs). Furthermore, NS8 was also able to diminish the proinflammatory effects of lipopolysaccharide (LPS) in mouse macrophage cell line RAW264.7 by inducing higher levels of IL-10. Specially, adding of the purified S-layer protein didn’t influence the production of IL-10. The specific ligand-host receptor interactions on the NS8 specific immune responses need to be learned further.
In summary, L. helveticus NS8 exhibited good probiotic and particularly immunomodulatory properties, with a potential for development of functional food commercially or therapeutic adjuvant for inflammatory diseases.
[Show abstract][Hide abstract] ABSTRACT: Background:
In light of the growing number of cancer survivors, the incidence of cardiovascular complications in these patients had also increased, while the effect of apatinib on the pharmacokinetic of cardioprotective drug (carvedilol) in rats or human is still unknown. The present work was to study the impact of apatinib on the metabolism of carvedilol both in vitro and vivo.
A specific and sensitive ultra-performance liquid-chromatography tandem mass spectrometry method was applied to determine the concentration of carvedilol and its metabolites (4'-hydroxyphenyl carvedilol [4'-HPC], 5'-hydroxyphenyl carvedilol [5'-HPC] and o-desmethyl carvedilol [o-DMC]).
The inhibition ratios in human liver microsomes were 10.28, 10.89 and 5.94% for 4'-HPC, 5'-HPC and o-DMC, respectively, while in rat liver microsomes, they were 3.22, 1.58 and 1.81%, respectively. The data in vitro of rat microsomes were consistent with the data in vivo that the inhibition of 4'-HPC and 5'-HPC formation was higher than the control group.
Our study showed that apatinib could significantly inhibit the formation of carvedilol metabolites both in human and rat liver microsomes. It is recommended that the effect of apatinib on the metabolism of carvedilol should be noted and carvedilol plasma concentration should be monitored.
[Show abstract][Hide abstract] ABSTRACT: Understanding the molecular basis of drug resistance and utilising this information to overcome chemoresistance remains a key challenge in oncology. Here we report that survivin, a key protein implicated in drug resistance, is overexpressed in cancer stem cell pool of doxorubicin-resistant breast cancer cells. Moreover, by utilising an active targeting system consisting of an RNA aptamer targeted against the epithelial cell adhesion molecule and a Dicer substrate survivin siRNA, we could deliver a high dose of the siRNA to cancer stem cells in xenograft tumours. Importantly, silencing of survivin with this aptamer-siRNA chimera in cancer stem cell population led to the reversal of chemoresistance, such that combined treatment with low dose of doxorubicin inhibited stemness, eliminated cancer stem cells via apoptosis, suppressed tumour growth, and prolonged survival in mice bearing chemoresistant tumours. This strategy for in vivo cancer stem cell targeting has wide application for future effective silencing of anti-death genes and in fact any dysregulated genes involved in chemoresistance and tumour relapse.
[Show abstract][Hide abstract] ABSTRACT: Although cancer stem cells have been well characterized in numerous malignancies, the fundamental characteristics of this group of cells, however, have been challenged by some recent observations: cancer stem cells may not necessary to be rare within tumors; cancer stem cells and non-cancer stem cells may undergo reversible phenotypic changes; and the cancer stem cells phenotype can vary substantially between patients. Here the current status and progresses of cancer stem cells theory is illustrated and via providing a panoramic view of cancer therapy, we addressed the recent controversies regarding the feasibility of cancer stem cells targeted anti-cancer therapy.
[Show abstract][Hide abstract] ABSTRACT: A two-stage case-control study was conducted to examine the association between six candidate U2-depedent spliceosome genes (SRSF1, SRSF2, SF3A1, SF3B1, SF1 and PRPF40B) and pancreatic cancer (PC). Subjects with one or two T alleles at rs2074733 in SF3A1 had a lower risk of PC compared to those with two C alleles in combined two populations (OR: 0.59, 95% confidence interval: 0.48-0.73, False discovery rate (FDR)-P = 1.5E-05). Moreover, the presence of the higher-risk genotype at rs2074733 plus smoking or drinking had synergic effects on PC risk. These findings illustrate that RNA splicing-related genes appear to be associated with the occurrence of PC, and show synergic interactions with smoking and drinking in the additive model. In the future, our novel findings should be further confirmed by functional studies and independent large-scale population studies.
[Show abstract][Hide abstract] ABSTRACT: Oxcarbazepine (OXC), a second-generation antiepileptic drug, undergoes rapid reduction with formation of the active metabolite 10,11-dihydro-10-hydroxy-carbazepine (MHD) in vivo. In this study, a method for simultaneous determination of OXC and MHD in rat plasma using ultra-performance liquid chromatography with tandem mass spectrometry (UPLC-MS-MS) was developed and validated. Under given chromatographic conditions, OXC, MHD and internal standard diazepam were separated well and quantified by electrospray positive ionization mass spectrometry in the multiple reaction monitoring transitions mode. The method validation demonstrated good linearity over the range of 10-2,000 ng/mL for OXC and 5-1,000 ng/mL for MHD. The lower limit of quantification was 5 ng/mL for OXC and 2.5 ng/mL for MHD, respectively. The method was successfully applied to the evaluation of the pharmacokinetics of OXC and MHD in rats, with or without pretreatment by ketoconazole (KET) and voriconazole (VOR). Statistics indicated that KET and VOR significantly affected the disposition of OXC and MHD in vivo, whereas VOR predominantly interfered with the disposition of MHD. This method is suitable for pharmacokinetic study in small animals.
Journal of chromatographic science 10/2015; DOI:10.1093/chromsci/bmv146 · 1.36 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Ethnopharmacological relevance:
Gastrodia elata Blume, a traditional Chinese herb, was widely used against convulsant, vertigo, paralysis, epilepsy, tetanus, asthma and immune dysfunctions. Gastrodin is one of the major bioactive components of Gastrodia elata and it is known for its anticonvulsive, anti-inflammatory, antiepileptic and neuroprotective effects.
Materials and methods:
An ultra high performance liquid chromatography-fluorescence detection (UHPLC-FLD) method was developed to determine gastrodin in rat plasma. Gastrodin and Thiamphenicol (internal standard, IS) were extracted from rat plasma by immediately protein precipitation. The pharmacokinetics of gastrodin in rats by following differently administered types was studies: intragastric administration of gastrodin (100mg/kg), parishin (116mg/kg, with the same mole of gastrodin moiety) and Gastrodia elata extract (2.3g/kg, with the same mole of gastrodin moiety). Non-compartmental pharmacokinetic profiles were constructed using the software of WinNonlin (Phoenix, version 6.3), and the pharmacokinetic parameters were compared using unpaired Student's t-test.
The results showed that the pharmacokinetic parameters, including Cmax, Tmax, AUC0-∞, t1/2, MRT, Vd, CL, were quite different among the three types of gastrodin administration. The administration of parishin and Gastrodia elata extract, which either could convert to gastrodin in vivo or contained free gastrodin and abundant gastrodin conjugates, gave rise to higher elimination half-life (t1/2) and mean residence time (MRT) values for gastrodin compared to free gastrodin administered.
The comparison of the pharmacokinetics of gastrodin among three different administered types of gastrodin in rats suggested that administration of parishin or Gastrodia elata extract in clinic may result in a longer duration time of action than that of the administration of free gastrodin. The results may provide some guidance for the clinical applications of parishin and Gastrodia elata.
Journal of ethnopharmacology 10/2015; 176. DOI:10.1016/j.jep.2015.10.007 · 3.00 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The thermal focal length of the Er:YSGG crystal was measured using the resonator stability condition in the LD side-pumped laser system, and thermal focal lengths under different average input optical powers were obtained. The grinding radius was calculated according to the measured thermal focal length, and the strong thermal lensing was compensated by grinding negative curvatures on the crystal ends with the calculated grinding radius. The average output power of 10.1 W at a repetition frequency of 20 Hz was achieved, corresponding to the slope efficiency of 6.5% and optical-optical efficiency of 5.5%. The average output power was increased by 2.58 times after compensating at 20 Hz. The maximum pulse energy 562 mJ was achieved after compensating at 16 Hz. The corresponding divergence angles were measured to be about θx = 8.13 mrad, θy = 7.42 mrad, and the energy instability was 1.13%.
[Show abstract][Hide abstract] ABSTRACT: In this study, vacuum infiltration-centrifugation of cold-induced oats at −18 °C was adopted in the extraction of oat antifreeze proteins (AFPs), and the effects of the oat AFPs on the physicochemical, rheological, and fermentation properties of frozen dough and the textural characteristics of steamed bread were investigated. Supplementation with oat AFPs lowered the freezable water content of the dough, resulting in some beneficial effects on final steamed bread. The rheological properties of the oat AFP group showed a greater fermentation capacity than did the control group (without oat AFP). A scanning electron microscopic analysis showed that supplementation with oat AFPs could protect the gluten matrix from disruption, thus resulting in superior textural properties in the steamed bread. In conclusion, oat AFPs could be used as a beneficial additive to frozen dough.
[Show abstract][Hide abstract] ABSTRACT: The pharmacokinetics of parishin, gastrodin, Gastrodia elata extract and Rhizoma Gastrodiae capsule was investigated by intragastric and/or intravenous administration to rats. Parishin was metabolized into nine metabolites after intravenous administration, and the area under the curve (AUC0–∞) of parishin and its metabolites (except parishin G and parishin E) increased nonlinearly from 72.5 to 220 mg/kg. When combining regression equation with the AUC0–∞ and dose of gastrodin injection, the percent conversion of parishin to gastrodin was obtained as 50 %. Based on multi-active metabolites of parishin in vivo, integrated pharmacokinetic mode was established. It is notable that each metabolite from parishin shares the similar metabolic process at three dosages of parishin and the bioavailability of parishin was approximately 14 %. The integrated pharmacokinetic mode was successfully applied to evaluate the holistic pharmacokinetics of gastrodin injection, G. elata extract and Rhizoma Gastrodiae capsule. The results showed that the holistic pharmacokinetics of gastrodin injection and G. elata extract was closed to that of gastrodin, but for parishin and Rhizoma Gastrodiae capsule, integrated pharmacokinetic parameters were more suitable to evaluate its holistic pharmacokinetics.
Pharmacokinetic study of Gastrodia elata in rats
[Show abstract][Hide abstract] ABSTRACT: Semi-metals might offer a stronger interaction and a better confinement for
terahertz wave than semiconductors, while preserve tunability. Particularly,
graphene-based materials are envisioned as terahertz modulators, filters and
ultra-broadband sources. However, the understanding of terahertz generation
from those materials is still not clear, thus limits us recognizing the
potential and improving device performances. Graphite, the mother material of
graphene and a typical bulk semi-metal, is a good system to study semi-metals
and graphene-based materials. Here we experimentally modulate and maximize the
terahertz signal from graphite surface, thus reveal the mechanism - surface
field driving photon induced carriers into transient current to radiate
terahertz wave. We also discuss the differences between graphite and
semiconductors; particularly graphite shows no temperature dependency from room
temperature to 80C. Above knowledge will help us understand terahertz
generations, achieve maximum output and electric modulation, in semi-metal or
graphene based devices.
[Show abstract][Hide abstract] ABSTRACT: A novel optical fiber torsion sensor head is proposed. A section of polarization-maintaining fiber (PMF) is spliced between single mode fiber (SMF), and a twist taper is fabricated by a commercial electric-arc fusion splicer in the middle of the PMF. The asymmetric characteristics are obtained by the twist taper so that a fiber torsion sensor with directional discrimination is fabricated. Due to the characteristics of the asymmetric structure, the torsion sensitivity for the twist rate from 0 rad/m to -8 rad/m reaches 2.392 nm/rad·m-1, and for the twist rate from 0 rad/m to 8 rad/m reaches 1.071 nm/rad·m-1 respectively.
[Show abstract][Hide abstract] ABSTRACT: Sm-Mn mixed oxide catalysts prepared by the coprecipitation method were developed, and their catalytic activities were tested for the selective catalytic reduction (SCR) of NO with ammonia at low temperature. The results showed that the amount of Sm markedly influenced the activity of the MnOx catalyst for SCR, that the activity of the Sm-Mn mixed oxide catalyst exhibited a volcano-type tendency with an increase in the Sm content, and that the appropriate mole ratio of Sm to Mn in the catalyst was 0.1. In addition, the presence of Sm in the MnOx catalyst can obviously enhance both water and sulfur dioxide resistances. The effect of Sm on the physiochemical properties of the Sm-MnOx catalyst were investigated by XRD, low-temperature N2 adsorption, XPS, and FE-SEM techniques. The results showed that the presence of Sm in the Sm-MnOx catalyst can restrain the crystallization of MnOx and increase its surface area and the relative content of both Mn4+ and surface oxygen (OS) on the surface of the Sm-MnOx catalyst. NH3-TPD, NO-TPD, and in situ DRIFT techniques were used to investigate the absorption of NH3 and NO on the Sm-MnOx catalyst and their surface reactions. The results revealed that the presence of Sm in the Sm0.1-MnOx catalyst can increase the absorption amount of NH3 and NO on the catalyst and does not vary the SCR reaction mechanism over the MnOx catalyst: that is, the coexistence of Eley-Rideal and Langmuir-Hinshelwood mechanisms (bidentate nitrate is the active intermediate), in which the Eley-Rideal mechanism is predominant.