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1.
Food Chem ; 304: 125446, 2020 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-31491715

RESUMO

Fused coumarins recently attracted strong scientific interest due to their potent pharmacological activities. In this study, density functional theory (DFT) calculations were performed to evaluate the antiradical activities of a series of coumarin-fused coumarins. By calculating the thermodynamic parameters, three primary mechanisms including hydrogen atom transfer (HAT), electron transfer followed by proton transfer (SET-PT) and sequential proton loss electron transfer (SPLET) were examined. It was found that in the gas and benzene phases, the studied compounds prefer to undergo HAT mechanism, while SPLET is more favored in polar media. The results also reveal the possibility of double HAT and double SPLET mechanisms for compound CC-6. Interestingly, a new polycyclic compound was generated by forming a new C5-O5' bond during the second HAT process at the 5'-OH in CC-6-R6 radical. In addition, the SPLHAT mechanism is proposed as a competitive pathway for radical scavenging by CC-4, CC-5 and CC-6.

2.
Food Chem ; 303: 125399, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31470274

RESUMO

It is still a challenge to solve the matrix interferences in veterinary drug residue analysis. In this study, we reported a thin layer chromatography (TLC)-high-performance liquid chromatography (HPLC) method for determining total florfenicol (FF) residues, expressed as florfenicol amine (FFA), in porcine edible tissues. The tissue homogenate were acid-hydrolyzed to liberate the bound residues and convert them into FFA. The hydrolysates were washed with ethyl acetate and subsequently extracted with ethyl acetate under alkaline conditions. The supernatants were concentrated through evaporation, defatted with hexane, purified by TLC and analyzed by HPLC at 225 nm. The optimal developing solvent for TLC purification was ethyl acetate-acetone-ammonium hydroxide mixtures (2:8:0.5, v/v/v). The method was fully validated according to decision 2002/657/EC, and could be used for the routine monitoring of FF residues in pig. TLC showed excellent purification efficiency, and was expected to solve the matrix interferences in veterinary drug residue analysis.

3.
Environ Pollut ; : 113464, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31677869

RESUMO

Cadmium (Cd) is a toxic metal that contributes to human diseases such as pediatric cancer and cardiovascular dysfunction. Epigenetic modification caused by Cd exposure is the major factor in etiology of environmentally-relevant diseases. However, the underlying epigenetic mechanism for Cd uptake and accumulation in food crops, particularly those growing in Cd-contaminated environments, is largely unknown. This study investigated uncharacterized regulatory mechanisms and biological functions of global DNA hypomethylation at CG sites that are associated with gene expression for Cd detoxification and accumulation in the food crop rice. Mutation of the CG maintenance enzyme OsMET1 confers rice tolerance to Cd exposure. Genome-wide analysis of OsMET1 loss of function mutant Osmet1 and its wild type shows numerous loci differentially methylated and upregulated genes for Cd detoxification, transport and accumulation. We functionally identified a new locus for a putative cadmium tolerance factor (here termed as OsCTF) and demonstrated that Cd-induced DNA demethylation is the drive of OsCTF expression. The 3'-UTR of OsCTF is the primary site of DNA and histone (H3K9me2) demethylation, which is associated with higher levels of OsCTF transcripts detected in the Osmet1 and Ossdg714 mutant lines. Mutation of OsCTF in rice led to hypersensitivity to Cd and the Osctf line accumulated more Cd, whereas transfer of OsCTF back to the Osctf mutant completely restored the normal phenotype. Our work unveiled an important epigenetic mechanism and will help develop breeding crops that contribute to food security and better human health.

5.
Metallomics ; 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31670356

RESUMO

Arsenic trioxide (As2O3) is one of the most effective drugs for the treatment of acute promyelocytic leukemia (APL), and induces the degradation of chimeric oncoprotein PML/RARα (P/R) and APL cell differentiation. Recent evidence has suggested that P/R fusion protein degradation by arsenic occurs through two steps, namely, rapid solubility change/shift of the P/R fusion protein following arsenic treatment (i.e., transfer of P/R protein from the soluble fraction to the insoluble pellet fraction), and subsequent degradation of these insoluble proteins. However, there is little information regarding the reversibility of arsenic induced P/R fusion protein solubility change as well as protein degradation in the insoluble fraction after removing arsenic. In this study, we used APL cell line NB4 or P/R and PML over-expressed 293T cells as well as HeLa cells to reveal the solubility change of P/R and PML by arsenic exposure, and further determined the fate of these insoluble proteins after the removal of arsenic. Here, for the first time, we found that arsenic induced P/R or PML protein solubility change is an irreversible process. Once arsenic induces a P/R or PML protein solubility change, these insoluble proteins could be degraded by the proteasomal pathway even without continuous arsenic treatment. However, PML and P/R proteins can be newly synthesized after the removal of arsenic, suggesting that great caution should be taken in the clinical therapy of APL patients before ending arsenic treatment.

6.
Medicine (Baltimore) ; 98(44): e17867, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689880

RESUMO

Glycogen storage disease (GSD) type IX, characterized by liver enlargement and elevated aminotransferase levels, is the most frequent type of GSD. The global incidence of GSD type IXa is only about 1/100,000 individuals. Case reports of GSD type IX are rare in China. We present the first case report of GSD type IXa in Northeast China caused by mutation of PHKA2.An 11-year-old boy was referred to our hospital because of liver enlargement with consistently elevated transaminase levels over 6 months.Histopathological results following an ultrasound-guided liver biopsy confirmed a diagnosis of GSD. Further genetic testing showed that the patient had GSD type IXa caused by the c.133C>T mutation in PHAK2.We placed the patient on a high-protein and high-starch diet and provided hepatoprotective and supportive therapy.The patient's transaminase levels decreased significantly and were nearly normal at 10-month follow-up.This is the first reported case of GSD type IXa in Northeast China. We hope that the detailed and complete report of this case will provide a reference for the diagnosis of liver enlargement of unknown etiology in future clinical practice.


Assuntos
Carcinoma Hepatocelular/virologia , Hepatite B Crônica/genética , Interleucinas/genética , Cirrose Hepática/virologia , Neoplasias Hepáticas/virologia , Polimorfismo de Nucleotídeo Único , Adulto , Consumo de Bebidas Alcoólicas/efeitos adversos , Grupo com Ancestrais do Continente Asiático/genética , Carcinoma Hepatocelular/genética , Estudos de Casos e Controles , Progressão da Doença , Feminino , Hepatite B Crônica/complicações , Humanos , Cirrose Hepática/genética , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , Mutação Puntual , Estudos Retrospectivos , Fumar/efeitos adversos
7.
Int J Neurosci ; : 1-8, 2019 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-31721620

RESUMO

Smoking is a risk factor of various diseases and the leading cause of preventable death. Nicotine is one of the main toxic compounds in cigarette smoke and harms multiple systems of the body, particularly neurons. The aim of the current study was to explore the mechanism of neurological changes underlying the toxicity of nicotine. Nicotine increased the levels of reactive oxygen species (ROS) in PC12 and HM cells in a concentration-dependent manner. Microscopy showed increased autophagic flux in nicotine-treated PC12 cells. Subsequent western blotting results showed that nicotine induced increases in the levels of LC3B-II and Beclin1, and decreased SQSTM1/p62 in a concentration-dependent manner. Finally, nicotine treatment reduced the length of TUBB3-positive axons and dendrites. Melatonin, a mitochondrially targeted antioxidant, reduced the ROS level, and blocked autophagy activation and the morphologic structural changes induced by nicotine.

8.
Behav Brain Res ; : 112319, 2019 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-31669346

RESUMO

Chronic cerebral hypoperfusion is an important risk factor for vascular dementia (VaD) and other brain dysfunctions, for which there are currently no effective medications available. In the present study, we investigated the potential therapeutic effects of cornel iridoid glycoside (CIG) on VaD in rats modeled by permanent bilateral common carotid artery ligation (2-vessel occlusion, 2VO). The object recognition test (ORT) and Morris water maze (MWM) test were conducted to evaluate the learning and memory function. Western blot analysis and immunohistochemical staining were used to detect the expression of related proteins. Results showed that intragastric administration of CIG (30, 60, and 120 mg/kg) for 3 months significantly increased the discrimination index in ORT and decreased the escape latency in MWM test, ameliorating the learning and memory deficit in 2VO rats. Further data indicated that CIG increased the expression of neurotrophic factors (NGF and BDNF) and their receptors (TrkA and TrkB), glutamate receptor subunits (NMDAR1 and GluR2) in the cerebral cortex and hippocampus of 2VO rats. In addition, CIG elevated the expression of PI3K subunits p110α and p85, further upregulated the phosphorylation of Akt, GSK3ß-ser9 and CREB in the cerebral cortex and hippocampus at 3 months after 2VO surgery. Collectively, CIG treatment improved learning and memory deficit induced by chronic cerebral hypoperfusion via increasing neurotrophic factors thus protecting glutamate receptors and activating PI3K/Akt/GSK3ß/CREB signaling pathway in rats. These results suggest that CIG may be beneficial to VaD therapy.

9.
BMC Med Genet ; 20(1): 169, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31694554

RESUMO

BACKGROUND: Proximal symphalangism is a rare disease with multiple phenotypes including reduced proximal interphalangeal joint space, symphalangism of the 4th and/or 5th finger, as well as hearing loss. At present, at least two types of proximal symphalangism have been identified in the clinic. One is proximal symphalangism-1A (SYM1A), which is caused by genetic variants in Noggin (NOG), another is proximal symphalangism-1B (SYM1B), which is resulted from Growth Differentiation Factor 5 (GDF5) mutations. CASE PRESENTATION: Here, we reported a Chinese family with symphalangism of the 4th and/or 5th finger and moderate deafness. The proband was a 13-year-old girl with normal intelligence but symphalangism of the 4th finger in the left hand and moderate deafness. Hearing testing and inner ear CT scan suggested that the proband suffered from structural deafness. Family history investigation found that her father (II-3) and grandmother (I-2) also suffered from hearing loss and symphalangism. Target sequencing identified a novel heterozygous NOG mutation, c.690C > G/p.C230W, which was the genetic lesion of the affected family. Bioinformatics analysis and public databases filtering further confirmed the pathogenicity of the novel mutation. Furthermore, we assisted the family to deliver a baby girl who did not carry the mutation by genetic counseling and prenatal diagnosis using amniotic fluid DNA sequencing. CONCLUSION: In this study, we identified a novel NOG mutation (c.690C > G/p.C230W) by target sequencing and helped the family to deliver a baby who did not carry the mutation. Our study expanded the spectrum of NOG mutations and contributed to genetic diagnosis and counseling of families with SYM1A.

10.
Toxicol Appl Pharmacol ; 384: 114775, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31669778

RESUMO

Acute promyelocytic leukemia (APL) is characterized by a reciprocal translocation between chromosomes 15 and 17, t(15;17), resulting in the expression of PML-RARα fusion protein, which disrupts the normal PML nuclear bodies (PML-NBs) to micro-speckled pattern, leading to loss of their original functions. Moreover, reformation of PML-NBs in APL by arsenic is considered as one of the important step for APL treatment. Leptomycin B (LMB), a nuclear export inhibitor, is commonly used to inhibit the proteins exporting from the nucleus to the cytoplasm. In the present study, we found that LMB could induce the reformation of PML-NBs in leukemia NB4 cells as well as in APL blast cells from the patients, implying that nuclear shuttle proteins might be involved in the reformation of PML-NBs. Herein, we further found that LMB totally lost the ability to induce PML-NBs reformation when the endogenous PML gene was knocked out, indicating that endogenous PML protein is probably involved in the reformation of PML-NBs. More interestingly, among all PML isoforms (i.e., seven isoforms), reformation of PML-NBs was only observed when co-transfection of PML-RARα with PML-I after LMB treatment. Similarly, deletion of nuclear export signal (NES) of PML-I could also reform PML-NBs, suggesting that the protein level of endogenous PML-I in nucleus is important for the reformation of PML-NBs that interfered by PML-RARα fusion protein. Additionally, LMB has synergistic effect with iAsIII on enhancing PML-RARα fusion protein degradation, and it might provide new insight into APL treatment at clinical level in the near future.

11.
Acta Pharmacol Sin ; 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31685976

RESUMO

Increasing levels of plasma urotensin II (UII) are positively associated with atherosclerosis. In this study we investigated the role of macrophage-secreted UII in atherosclerosis progression, and evaluated the therapeutic value of urantide, a potent competitive UII receptor antagonist, in atherosclerosis treatment. Macrophage-specific human UII-transgenic rabbits and their nontransgenic littermates were fed a high cholesterol diet for 16 weeks to induce atherosclerosis. Immunohistochemical staining of the cellular components (macrophages and smooth muscle cells) of aortic atherosclerotic lesions revealed a significant increase (52%) in the macrophage-positive area in only male transgenic rabbits compared with that in the nontransgenic littermates. However, both male and female transgenic rabbits showed a significant decrease (45% in males and 31% in females) in the smooth muscle cell-positive area compared with that of their control littermates. The effects of macrophage-secreted UII on the plaque cellular components were independent of plasma lipid level. Meanwhile the wild-type rabbits were continuously subcutaneously infused with urantide (5.4 µg· kg-1· h-1) using osmotic mini-pumps. Infusion of urantide exerted effects opposite to those caused by UII, as it significantly decreased the macrophage-positive area in male wild-type rabbits compared with that of control rabbits. In cultured human umbilical vein endothelial cells, treatment with UII dose-dependently increased the expression of the adhesion molecules VCAM-1 and ICAM-1, and this effect was partially reversed by urantide. The current study provides direct evidence that macrophage-secreted UII plays a key role in atherogenesis. Targeting UII with urantide may promote plaque stability by decreasing macrophage-derived foam cell formation, which is an indicator of unstable plaque.

12.
Cell Death Differ ; 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31685978

RESUMO

Cancer cells reprogram their energy metabolic system from the mitochondrial oxidative phosphorylation (OXPHOS) pathway to a glucose-dependent aerobic glycolysis pathway. This metabolic reprogramming phenomenon is known as the Warburg effect, a significant hallmark of cancer. However, the detailed mechanisms underlying this event or triggering this reprogramming remain largely unclear. Here, we found that histone H2B monoubiquitination (H2Bub1) negatively regulates the Warburg effect and tumorigenesis in human lung cancer cells (H1299 and A549 cell lines) likely through controlling the expression of multiple mitochondrial respiratory genes, which are essential for OXPHOS. Moreover, our work also suggested that pyruvate kinase M2 (PKM2), the rate-limiting enzyme of glycolysis, can directly interact with H2B in vivo and in vitro and negatively regulate the level of H2Bub1. The inhibition of cell proliferation and nude mice xenograft of human lung cancer cells induced by PKM2 knockdown can be partially rescued through lowering H2Bub1 levels, which indicates that the oncogenic function of PKM2 is achieved, at least partially, through the control of H2Bub1. Furthermore, PKM2 and H2Bub1 levels are negatively correlated in cancer specimens. Therefore, these findings not only provide a novel mechanism triggering the Warburg effect that is mediated through an epigenetic pathway (H2Bub1) but also reveal a novel metabolic regulator (PKM2) for the epigenetic mark H2Bub1. Thus, the PKM2-H2Bub1 axis may become a promising cancer therapeutic target.

13.
Artigo em Inglês | MEDLINE | ID: mdl-31721336

RESUMO

RATIONALE: Interactions of drug molecules and proteins play an important role in physiological and pathological processes in vivo. It is of significance to establish a reliable strategy for studying protein-drug ligand interactions and would be helpful for the design and screening of new drugs in pharmacological research. METHODS: The interactions between four indole alkaloids (IAs) extracted from Ophiorrhiza japonica and myoglobin (Mb) protein were investigated by using a multi-spectrometric and computational method of native electrospray ionization mass spectrometry (Native ESI-MS), hydrogen/deuterium exchange mass spectrometry (HDX-MS), circular dichroism (CD) and molecular docking (MD). RESULTS: The IA bound-Mb complexes were analyzed by native ESI-MS, with the obtained stoichiometry of protein-ligand at 1:1, 1:2, 1:3, respectively. Binding constants were measured according to the interpretation of MS spectra. MD complemented MS measurement, probed that the binding sites and modes of four IAs to Mb. Analyses of CD and HDX-MS demonstrated that the exposure to IAs could affect the conformation of Mb by decreasing the α-helix content and make Mb more susceptible to HDX at the backbone. CONCLUSIONS: A new mass spectrometry-based integrated analysis method has been developed to successfully study the interactions of Mb and IAs extracted from Ophiorrhiza japonica. The experimental and calculation results have good consistency, revealing all of the four IA molecules could bind to Mb to form 1:1, 1:2 and 1:3 Mb-IA complexes, respectively. The order of binding ability of these IAs to Mb was Ophiorrhine B > Compound C > Ophiorrhine A > Compound D. CD and HDX-MS results indicated that binding with IAs destabilizes resulted of Mb. HDX-MS analysis suggests that Mb becomes more accessible to HDX, indicating that IAs binding destabilizes the structure of Mb. In addition, interacting with IAs affected the overall structure of Mb, ascribed to the decrease of α-helix content and less folding of backbone.

14.
Medicine (Baltimore) ; 98(42): e17591, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31626131

RESUMO

BACKGROUND: Spinal cord ischemia-reperfusion injury (SCII) is a common complication of spinal surgery as well as thoracic and abdominal surgery. Acute cytotoxic edema is the key pathogenic alteration. Therefore, avoiding or decreasing cellular edema has become the major target for SCII treatment. METHODS: The antiedema activity of ginsenoside Rb1 on aquaporin (AQP) 4, nerve growth factor (NGF), and brain-derived neurotrophic factor expression was detected by western blot and real-time polymerase chain reaction under conditions of oxygen-glucose deprivation/reoxygenation (OGD/R) in a rat astrocyte model in vitro. In addition, the cellular membrane permeability of AQP4 overexpressing cells or AQP4 small interfering RNA-transfected cells was detected. RESULTS: Ginsenoside Rb1 significantly prevented OGD/R-induced AQP4 downregulation in rat astrocytes. In addition, ginsenoside Rb1 treatment or AQP4 overexpression in rat astrocytes significantly attenuated the OGD/R-induced increase of cellular membrane permeability. Moreover, ginsenoside Rb1 obviously prevented the OGD/R-induced decrease of NGF and BDNT expression in rat astrocytes. CONCLUSION: These findings demonstrate that ginsenoside Rb1 can relieve spinal cord edema and improve neurological function by increasing AQP4 expression.


Assuntos
Aquaporina 4/genética , Astrócitos/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Ginsenosídeos/farmacologia , Glucose/metabolismo , Oxigênio/metabolismo , Traumatismo por Reperfusão/genética , Animais , Animais Recém-Nascidos , Aquaporina 4/biossíntese , Astrócitos/efeitos dos fármacos , Astrócitos/patologia , Western Blotting , Células Cultivadas , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , RNA/genética , Ratos , Ratos Sprague-Dawley , Traumatismo por Reperfusão/tratamento farmacológico , Traumatismo por Reperfusão/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Medula Espinal/metabolismo , Medula Espinal/patologia
15.
Exp Ther Med ; 18(4): 2749, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31572523

RESUMO

[This retracts the article DOI: 10.3892/etm.2016.3999.].

16.
J Med Virol ; 2019 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-31587312

RESUMO

Coxsackievirus A16 (CA16) remains the most common causative agent of hand, foot, and mouth disease (HFMD), and is related to high incidence and critical complications. Vitamin D receptor (VDR) activity might affect the outcome of CA16 infection. Our case-control research aims to evaluate the relationship between VDR polymorphisms in the gene encoding and susceptibility to and severity of HFMD due to CA16. Three SNPs of VDR gene were selected according to functional prediction and linkage disequilibrium, and were examined utilizing the SNPscan method to identify possible associations with HFMD caused by CA16. A significant relationship was found in the HFMD cases of polymorphism rs11574129 (GA vs. GG: odds ratio (OR) = 0.068, 95% confidence interval (CI) = 0.007-0.693, P = 0.023; GA+AA vs. GG: OR = 0.322, 95%CI = 0.106-0.984, P = 0.047), and vitamin D levels in genotype AA were significantly higher than those in genotype GG (P < 0.05). These results suggest that VDR rs11574129 may influence genetic susceptibility to CA16-associated HFMD. This article is protected by copyright. All rights reserved.

17.
Medicine (Baltimore) ; 98(38): e17274, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31568007

RESUMO

BACKGROUND: Weight status and autism spectrum disorder (ASD) are rising public health concerns. An increasing number of reports indicate that individuals with ASD may have unhealthy weight status, but the evidence is mixed. To understand the weight status in individuals with ASD and provide strategies for prevention and intervention, we describe the protocol for a systematic review and meta-analysis aimed at assessing the prevalence of obesity, overweight, and underweight in ASD. METHODS: A broad range of key bibliographic databases including MEDLINE (PubMed), Embase, Cochrane, and ISI Web of Science will be searched to identify studies reporting the prevalence of obesity, overweight, and underweight in patients with ASD. Retrieved records will be independently screened by 2 authors and relevant estimates will be extracted from studies reporting data on obesity, overweight, and underweight prevalence among individuals with ASD. The assessment of study quality will be conducted primarily using the Newcastle-Ottawa scale and checklist proposed by the Joanna Briggs Institute. Prevalence estimates of obesity and overweight will be separately pooled using random-effects model. The pooled estimates will be summarized and presented by regional groupings. Subgroup analysis will be conducted for variables (such as study setting, participants' age, and geographical region) across studies, depending on data availability. Between-study heterogeneity will be assessed using the I statistic and explored through subgroup analyses. This systematic review and meta-analysis will be reported following the preferred reporting items for systematic reviews and meta-analyses checklist and the meta-analysis of observational studies in epidemiology statements guidelines for meta-analysis and systematic reviews of observational studies. RESULTS: In this study, we will outline details of the aims and methods on the meta-analysis of weight status of individuals with ASD. CONCLUSION: The results of this study will summarize the current data of weight status of individuals with ASD. REGISTRATION: PROSPERO-National Institute of Health Research (NIHR) Prospective Register of Systematic Reviews (CRD42019130790).


Assuntos
Transtorno do Espectro Autista/complicações , Peso Corporal , Criança , Humanos , Obesidade/complicações , Obesidade/psicologia , Sobrepeso/complicações , Sobrepeso/psicologia , Obesidade Pediátrica/complicações , Obesidade Pediátrica/psicologia , Magreza/complicações , Magreza/psicologia
18.
Zhongguo Zhong Yao Za Zhi ; 44(15): 3221-3225, 2019 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-31602875

RESUMO

The non-starch polysaccharides,mainly composed of glucomannans,are the major bioactive compounds in Dendrobium catenatum. In order to evaluate the quality of the medicinal materials and guide the production and processing,a quantification method of non-starch polysaccharides was established by stems of D. catenatum C15 strain collected from the pear epiphytic cultivation. The non-starch polysaccharides were obtained by " water extraction,α-amylase pretreatment,and alcohol precipitation once" method. The contents of starches,non-starch polysaccharides and monosaccharides were analyzed. In addition,the system suitability was tested. Compared with method of the Chinese Pharmacopoeia( 2015 edition),the contents of total polysaccharides,glucose,and mannose were decreased by 20. 9%,58. 8% and 1. 6% respectively. The method effectively digested starch and retained non-starch polysaccharides,and the analysis result was accurate and repeatable. Therefore,it is suitable for the content measurement of non-starch polysaccharides of D. catenatum. Furthermore,it could be an alternative method for quality control of D. catenatum and a reference in the determination of non-starch polysaccharides in other starch-containing medicinal materials.


Assuntos
Dendrobium/química , Polissacarídeos/análise , Monossacarídeos/análise , Compostos Fitoquímicos/análise , Amido/análise
19.
Microbiologyopen ; : e951, 2019 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-31642186

RESUMO

Chronic persistent stress is an important cause of gastritis, but the underlying mechanism remains to be further researched, especially the role of the gastric microbiota in this process. Here, we used the water avoidance stress (WAS) test in mouse models for chronic stress-induced gastritis to investigate the underlying mechanisms of this disease. The effect of stress on the gastric microbiota was analyzed based on 16S rRNA sequencing; the changes in hydrogen sulfide (H2 S) and inflammatory cytokine levels in gastric tissues were detected by Western blotting, ELISA, immunofluorescence, and qRT-PCR. Hematoxylin and eosin staining was used as an indicator of the gastritis histological score. This finding is consistent with previous studies showing that gastric H2 S is negatively associated with the inflammatory index and might protect the gastrointestinal tract from inflammation. WAS-induced gastritis was associated with a reduction in H2 S release, which appeared to affect the homeostasis of the gastric microbiota of mice. Inflammation and microbial dysbiosis were partially reversed by sodium hydrosulfide (NaHS) and vitamin B6 (VB6) supplementation, suggesting the therapeutic potential of VB6 supplementation for the treatment of stress-induced gastritis. Gastritis has a serious impact on health and quality of life. An increasing number of people are suffering from chronic gastritis linked to a high-stress lifestyle, and our research provides clues for the prevention and treatment of stress-induced gastritis.

20.
Pain ; 2019 Oct 18.
Artigo em Inglês | MEDLINE | ID: mdl-31651580

RESUMO

Patients with chronic pain often report being sensitive to pain at night before falling asleep, a time when the synchronization of cortical activity is initiated. However, how cortical activity relates to pain sensitivity is still unclear. Since sleep is characterized by enhanced cortical delta power, we hypothesized that enhanced cortical delta power may be an indicator of intensified pain. To test this hypothesis, we used pain thresholds tests, EEG/electromyogram recordings, c-Fos staining and chemogenetic and pharmacological techniques in mice. We found that sleep deprivation or pharmacologic enhancement of EEG delta power by reserpine and scopolamine dramatically decreased mechanical pain thresholds, but not thermal withdrawal latency, in a partial sciatic-nerve ligation model of neuropathic pain mice. On the contrary, suppression of EEG delta power using a wake-promoting agent modafinil significantly attenuated mechanical allodynia. Moreover, when EEG delta power was enhanced, c-Fos expression decreased in most regions of the cortex, except the anterior cingulate cortex (ACC), where c-Fos was increased in the somatostatin and parvalbumin positive GABAergic neurons. Chemogenetic activation of GABAergic neurons in ACC enhanced EEG delta power and lowered mechanical pain thresholds simultaneously in naïve mice. However, chemogenetic inhibition of ACC GABAergic neurons could not block mechanical allodynia. These results provided compelling evidence that elevated EEG delta power is accompanied with aggravated neuropathic pain, whereas decreased delta power attenuated it, suggesting that enhanced delta power can be a specific marker of rising chronic neuropathic pain and that wake-promoting compounds could be used as analgesics in the clinic.

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