<span style="font-family:Verdana;">The aim of this study was to investigate the effect of time o</span><span style="font-family:Verdana;">n</span> <i><i><span...<span style="font-family:Verdana;">The aim of this study was to investigate the effect of time o</span><span style="font-family:Verdana;">n</span> <i><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"></span></i><span style="font-family:Verdana;"> maturation of bovine oocytes and of the addition of follicular fluid on meiotic progression. The cumulus-oocyte complexes (COCs) collected from 3 to 6 mm follicles were obtained from ovaries of slaughtered female animals. The medium of maturation was supplemented or not with 20 μL follicular fluid (FF);661 oocytes were matured </span><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"> (extrusion of the first polar corpuscle) for 22 hours with </span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">added </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">follicular fluid (AFF) (72.01%) or without follicular fluid (WFF) (67.53%) and 679 oocytes were matured <i></i></span><i><i><span style="font-family:Verdana;">in vitro</span></i></i><span style="font-family:Verdana;"></span><span style="font-family:Verdana;"> for 26 hours (extrusion of the first polar corpuscle) with AFF (92.1%) and WFF (77.15%). The results of extrusion of the second polar corpuscle as an event related to the fertilization percentages showed that the increase in the fertilization rate is maintained at 26 hours with AFF (79.45%), but the percentage decreases WFF (65.08%). After 22 hours, the fertilization rate was 62.38% AFF and 53.40% WFF. The developmental competence of bovine oocytes is affected by the duration of maturatio</span><span style="font-family:Verdana;">n </span><i><i><i><i><span style="font-family:Verdana;">in vitro</span></i></i></i></i><span style="font-family:Verdana;"></span><span style="font-family:Verdana;"> and the inclusion in the FF culture medium. The use of follicular fluid in th</span><span style="font-family:Verdana;">e </span><i><i><i><i><i><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"><i></i></span><i><span> </span></i></i></i></i></i></i><span style="font-family:Verdana;"></span><span style="font-family:Verdana;"></span><span></span><span style="font-family:Verdana;">maturation medium may be a biological strategy to increase the cumulus expansion, the nuclear maturation and the</span><i><i><i><i><i><i><span style="font-family:Verdana;"> <i></i></span><i><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"><i> </i></span></i></i></i></i></i></i></i><span style="font-family:Verdana;"></span><span style="font-family:Verdana;"></span><span style="font-family:Verdana;">fertilization.</span></span></span></span>展开更多
Trinitrotoluene (TNT) increased the formation of adrenochrome from adrenaline and the formation of formaldehyde from methanol in rat liver mitochondria and microsomes in vitro as well as in monkey liver mitrochondria ...Trinitrotoluene (TNT) increased the formation of adrenochrome from adrenaline and the formation of formaldehyde from methanol in rat liver mitochondria and microsomes in vitro as well as in monkey liver mitrochondria and microsomes in vivo. The effects were more prominent at higher TNT concentrations. These findings indicate that TNT enhances the production of superoxide radicals (O_2^-) and hydrogen peroxide (H_2O_2). The production of O_2^- was more prominent in systems containing added TNT than in those containing added benzyl viologen. H_2O_2 production by mitochondria was more pronounced in the liver than in other organs, but its production by microsomes was more pronounced in the brain than in other organs. The results suggest that TNT undergoes cycling reduction which produces oxidative stress. 1989 Academic Press, Inc.展开更多
BACKGROUND Liver fibrosis is a common health problem worldwide and there is still a lack of effective medicines.The Chinese herbal medicine,Gan Shen Fu Fang(GSFF)is composed of salvianolic acid B and diammonium glycyr...BACKGROUND Liver fibrosis is a common health problem worldwide and there is still a lack of effective medicines.The Chinese herbal medicine,Gan Shen Fu Fang(GSFF)is composed of salvianolic acid B and diammonium glycyrrhizinate.In this study,we observed the effects of GSFF on liver fibrosis in vivo and in vitro in an attempt to provide some hope for the treatment.AIM To observe the effects of GSFF on liver fibrosis in vivo and in vitro and investigate the mechanism from the perspective of the inflammatory response and extracellular signal-regulated kinase(ERK)phosphorylation.METHODS Common bile duct-ligated rats were used for in vivo experiments.Hepatic stellate cells-T6(HSC-T6)cells were used for in vitro experiments.Hematoxylin and eosin staining and Masson staining,biochemical assays,hydroxyproline(Hyp)assays,enzyme-linked immunoasorbent assay and western blotting were performed to evaluate the degree of liver fibrosis,liver function,the inflammatory response and ERK phosphorylation.The CCK8 assay,immunofluorescence and western blotting were applied to test the effect of GSFF on HSC-T6 cell activation and determine whether GSFF had an effect on ERK phosphorylation in HSC-T6 cells.RESULTS GSFF improved liver function and inhibited liver fibrosis in common bile ductligated rats after 3 wk of treatment,as demonstrated by histological changes,hydroxyproline assays and collagen I concentrations.GSFF alleviated inflammatory cell infiltration and reduced the synthesis of pro-inflammatory cytokines[tumor necrosis factor-α(TNF-α)and interlukin-1β]and NF-κB.In addition,GSFF decreased ERK phosphorylation.In vitro,GSFF inhibited the viability of HSC-T6 cells with and without transforming growth factorβ1(TGF-β1)stimulation and decreased the synthesis of collagen I.GSFF had the greatest effect at a concentration of 0.5μmol/L.GSFF inhibited the expression ofα-smooth muscle actin(α-SMA),a marker of HSC activation,in HSC-T6 cells.Consistent with the in vivo results,GSFF also inhibited the phosphorylation of ERK and downregulated the expression of NF-κB.CONCLUSION GSFF inhibited liver fibrosis progression in vivo and HSC-T6 cell activation in vitro.These effects may be related to an alleviated inflammatory response and downregulated ERK phosphorylation.展开更多
Liver injury is a common cause of drug approval withdrawal during drug development,pre-clinical research,and clinical treatment.If not properly treated,patients with severe liver injury can suffer from acute liver fai...Liver injury is a common cause of drug approval withdrawal during drug development,pre-clinical research,and clinical treatment.If not properly treated,patients with severe liver injury can suffer from acute liver failure or even death.Thus,utilization of the convenient in vitro hepatotoxicity assessment model for early detection of drug-induced hepatotoxicity is vital for drug development and safe personalized medication.Biomaterials(e.g.,hydrogels,nanofibers,decellularized liver matrix)and bioengineering technologies(e.g.,microarrays,micropatterns,3D printing,and microfluidics)have been applied for in vitro hepatotoxicity assessment models.This review summarizes the structure and functions of the liver as well as the components of in vitro hepatotoxicity assessment models.In addition,it highlights the latest advances in developing hepatotoxicity models with the ultimate goal of further clinical translation.展开更多
[ Objective] To investigate the optimal culture system for in vitro fertilization (IVF) of oocyte in bovine. [ Method] The IVF of mature bovine oocytes was conducted and the fertilized eggs were cultured in vitro wi...[ Objective] To investigate the optimal culture system for in vitro fertilization (IVF) of oocyte in bovine. [ Method] The IVF of mature bovine oocytes was conducted and the fertilized eggs were cultured in vitro with different culture systems. In the traditional culture system, the TALP medium and BO medium were used as fertilization medium, respectively; and M-199 medium supplemented with 5% FCS was used as fertilized egg culture medium. In the transitional culture system, the TALP medium and BO medium were used as fertilization medium; 60% TALP and 40% M-199 supplemented with 5% FCS and 60% BO and 40% M-199 supplemented with 5% FCS were used as fertilized egg culture medium, respectively. The effects of different culture systems on fertilization rate and cleavage rate were observed. E Result] In the transitional culture system (with TALP medium as fertilization medium and with 60% TALP and 40% M-199 supplemented with 5% FCS as fertilized egg culture medium), the fertilization rate and cleavage rate were increased to 77.8% and 55.6%, respectively. [ Conclusion] The transitional culture system (with TALP medium as fertilization medium and with 60% TALP and 40% M-199 supplemented with 5% FCS as fertilized egg culture medium) is the optimal culture system for IVF of bovine oocyte.展开更多
Heat stress is one of the main reasons for reproductive performance decrease in cattle, resulting in severe economic losses. The aim of this study was to evaluate the effect of heat stress during maturation, fertiliza...Heat stress is one of the main reasons for reproductive performance decrease in cattle, resulting in severe economic losses. The aim of this study was to evaluate the effect of heat stress during maturation, fertilization and development of in vitro produced bovine embryos. Cumulus oocyte complexes (COCs) were obtained by follicular puncture from slaughterhouse ovaries and after identification, were divided into four groups: control (CG), exposed 1 (EG1), exposed 2 (EG2), and exposed 3 (EG3). The oocytes of the group CG and CG3 were cultured at 38°C and the oocytes of group EG1 and EG2 were cultured at 40°C during the maturation period (24 hours at 5% CO2 in air). After the maturation period, oocytes of group CG, EG1, EG2, and EG3 were fecundated with frozen thawed semen. The oocytes of CG, EG2 and EG3 groups were cultured at 38°C, and the group EG1 was cultured at 40°C (18 hours at 5% CO2 in air). After that, the CG and EG2 groups were cultured in SOF at 38°C and the groups EG1 and EG3 at 40°C during embryonic development. The embryos were evaluated for cleavage, morula and blastocyst rates by optical microscopy. In control (CG) and EG3 groups, the oocytes showed uniform expansion of cumulus cells, classified as moderate to high, with brown color and uniform appearance of the ooplasm. In the oocytes exposed to 40°C (EG1 and EG2) we observed a decrease in the expansion of cumulus cells, and the same showed rounded appearance and retraction of the ooplasm with dark coloration. The control group (CG) had 68.23% ± 2% of cleavage, 50.16% ± 2% morulas, and 43.28% ± 1% blastocysts. Whereas the EG2 had 31.46% ± 2% cleavage, 35.64% ± 2% morula, and no blastocysts development. The EG3 had 3.7% ± 2% cleavage, and no embryo production. These data suggest that in all stages of exposure to heat stress, the embryos and the gametes are susceptible, leading to a decrease in embryonic development.展开更多
AIM To investigate the effects of taxol onSMMC-7721 human hepatoma and itsmechanisms.METHODS In vitro cell growth was assessedby trypan blue exclusion method.Experimentalhepatoma model was established by seedingSMMC-7...AIM To investigate the effects of taxol onSMMC-7721 human hepatoma and itsmechanisms.METHODS In vitro cell growth was assessedby trypan blue exclusion method.Experimentalhepatoma model was established by seedingSMMC-7721 cells subcutaneously into Balb/c(nu/nu)nude mice.In vivo tumor growth wasdetermined by measurement of tumor diameterwith Vernier calipers.The syntheses of DNA,RNA and protein were analyzed by incorporationof ~3H-thymidine,~3H-uridine and ~3H-leucinerespectively.Using light and electronmicroscopes to observe the morphologicalchanges of cells including mitosis andapoptosis.RESULTS Taxol was effective against SMMC-7721 human hepatoma cell growth in the rangesof 2.5 nmol/L-10 nmol/L with mitotic arrestand apoptosis in vitro.DNA,RNA and proteinsyntheses in cells were also obviouslysuppressed by in vitro treatment of taxol for72 h.Taxol at 2.5 nmol/L reduced ~3H-thymidineuptake to about 34% of the control value(P【0.05).Increasing the dose of taxol to20 nmol/L resulted in a greater decrease in ~3H-thymidine incorporation to 60% of the controlvalue(P【0.01).At a concentration of 20 nmol/L,the ~3H-uridine and ~3H-leucine uptakeswere reduced to 52%(P【0.05)and 63%(P【0.01),respectively.In vivo,taxolsignificantly inhibited SMMC-7721 tumor growthat 10 mg/kg,i.p.,once daily for 10 d.A morethan 90% decrease in tumor volume wasobserved by day 11(P【0.01)similarly withmitotic arrest and cell apoptosis.CONCLUSION Taxol has a marked anticanceractivity in SMMC-7721 human hepatoma both invitro and in nude mice.Its mechanisms might beassociated with mitotic arrest,subsequently,apoptosis of the hepatoma cells.No obvioustoxicity was observed with in vivoadministration of taxoi.展开更多
The use of an internal control in a multiplex-PCR assay for sex determination of In Vitro-produced bovine embryos was evaluated in biopsies of groups of 54 fresh and 44 frozen embryos. The internal controls used were ...The use of an internal control in a multiplex-PCR assay for sex determination of In Vitro-produced bovine embryos was evaluated in biopsies of groups of 54 fresh and 44 frozen embryos. The internal controls used were the primers BOV 1 and BOV 2, which amplify a product with 626 base pairs (bp) of bovine mitochondrial DNA ND5 gene. The primers BRY.4aF and BRY.4aR were used for bovine Y chromosome sequence amplification. The specificity of multiplex- PCR reactions realized in biopsies corresponding to about 20% of each fresh embryo (10 male and 10 female) by means of confirming the sexing in the remaining embryo content (~80%) presented 100% specificity. Amplicons of the internal control and Y chromosome were both amplified until dilution corresponding to 6.25% of total extracted DNA from a male embryo. Sex determination was possible in 53 (98.1%) fresh embryos and 40 (90.9%) frozen embryos. The products related to the Y chromosome and mitochondrial DNA were simultaneously amplified in 34 (63%) fresh embryos and 27 (61.4%) frozen embryos, showing a male embryo. The female sex, distinguished by internal control amplification only, was detected in 19 (35.2%) and 13 (29.5%) biopsies, respectively, of fresh and frozen embryos. In one (1.8%) and four (9.1%) biopsies of fresh and frozen embryos, respectively, neither product was amplified, most likely due to the absence of embryonic cells or the presence of embryonic cells going through apoptosis. The multiplex-PCR assay developed in this work showed avoided the limitation of a lack of an internal standard, and was also sensitive, specific, and efficient in reaction failure identification. This technique shows great potential for use on a commercial scale in routine sex determination of In Vitro-produced embryos.展开更多
Olmesartan Medoxomil (OLM), Ramipril (RPL) & Fenofibric acid (FA) are used to treat hypertension and cardiovascular disease. These drugs undergo hydrolytic metabolism by the enzyme liver esterase and converts into...Olmesartan Medoxomil (OLM), Ramipril (RPL) & Fenofibric acid (FA) are used to treat hypertension and cardiovascular disease. These drugs undergo hydrolytic metabolism by the enzyme liver esterase and converts into their respective active metabolites Olmesartan (OL), Ramiprilat (RPT) and Fenofibric acid (FA) for OLM, RPL and FEN respectively. In this study the competitive metabolism of OLM, in presence of RPL and FEN was investigated in rat liver s9 fractions using a validated LC-MS method. Olmesartan Medoxomil was found to be highly reactive to the rat liver S9 fractions and formation of active metabolite Olmesartan is highest. The rate of formation of active metabolite Olmesartan reduced by 12.68% in the presence Ramipril and 6.56% in presence of Fenofibrate. A marked reduction of 18.96% was found in the formation of active metabolite Olmesartan from Olmesartan Medoxomil when all the three drugs are in combination.展开更多
The in vitro maturation, fertilization and development of bovine ovary oocytes in two differentcultural systems A and B were studied under the conditions of 38.5℃,5%CO2,95%air and 100%humidity.The maturation rates we...The in vitro maturation, fertilization and development of bovine ovary oocytes in two differentcultural systems A and B were studied under the conditions of 38.5℃,5%CO2,95%air and 100%humidity.The maturation rates were 94.5%and 91.3%,respectively,and the difference wasextremely significant.Frozen semen were thawed and sperm were capacitated with three kinds ofcapacitation agents for fertilization.The pronucleus rates were 76%,65%-68%and 62%respectively.The rates of embryos developed to morula and blastocyst were 19%,16% and 17%respectively.The developmental rates of embryos cocultured with bovine oviductal epithelium cellsand bovine granulosa cells were 25% and 23.4% respectively,with no significant difference. Freshembryos were transplanted into 15 recipicns,and three of them were pregnant and calves were bornin 1990 and 1991.The pregnant rate was 20%.The emryos developed faster before 8-cell stage andslower after 8-cell stage,in vitro than in vivo.展开更多
It has been recognized that alpha-fetoprotein (AFP),as an oncofetal antigen, re-expresses in large amounts inadult tumor cells and serves clinically useful purposes asa tumor marker assay. However, its biological acti...It has been recognized that alpha-fetoprotein (AFP),as an oncofetal antigen, re-expresses in large amounts inadult tumor cells and serves clinically useful purposes asa tumor marker assay. However, its biological activiticsare still far from clear. In thc present study, the ability ofAFP to stimulate tumor cell growth was observed by invitro test system. The new finding indicates that AFPcontributes to the generation and development of tumorand is an important target action site of tumor therapy.展开更多
Various systems by using electric pulse, calcium, or polyethylene glycol have been developed in the past decade for the in vitro fusion of plant gametes. These in vitro systems provide a new way to study the fertiliza...Various systems by using electric pulse, calcium, or polyethylene glycol have been developed in the past decade for the in vitro fusion of plant gametes. These in vitro systems provide a new way to study the fertilization mechanisms of plants. In this study, we developed a bovine serum albumin (BSA)-mediated fusion system for the in vitro fusion of maize gametes. The in vitro fusion of the isolated single egg cell and sperm cell of maize was observed microscopically in the BSA solution and the fertilized egg cell showed normal cell wall regeneration and nuclear division. The effects of the BSA concentration, pH value and calcium level on the efficiency of the maize gamete fusion were also assessed. BSA concentration and pH value did significantly affect the efficiency of the gamete fusion. Calcium was not necessary for the gamete fusion when BSA was present. The optimal solution for the gamete fusion contained 0.1% BSA, pH 6.0. The fusion frequency was as high as 96.7% in that optimal solution. This new in vitro fertilization system offers an alterna- tive tool for the in vitro study of fertilization mechanisms with much simpler manipulating procedure than PEG system, and it will be especially useful for the in vitro study of the calcium dynamics during plant fertilization.展开更多
AIM: To study liver cell apoptosis caused by the toxicity of selenium and observe the alteration of choline compounds using in vitro 9.4T high resolution magnetic resonance spectroscopy. METHODS: Twenty male Wistar ra...AIM: To study liver cell apoptosis caused by the toxicity of selenium and observe the alteration of choline compounds using in vitro 9.4T high resolution magnetic resonance spectroscopy. METHODS: Twenty male Wistar rats were randomly divided into two groups. The rats in the treatment group were intraperitoneally injected with sodium selenite and the control group with distilled water. All rats were sacrifi ced and the livers were dissected. 1H-MRS data were collected using in vitro 9.4T high resolution magnetic resonance spectrometer. Spectra were processed using XWINNMR and MestRe-c 4.3. HE and TUNEL staining was employed to detect and confi rm the change of liver cells. RESULTS: Good 1H-MR spectra of perchloric acid extract from liver tissue of rats were obtained. The conventional metabolites were detected and assigned. Concentrations of different ingredient choline compounds in treatment group vs control group were as follows: total choline compounds,5.08 ± 0.97 mmol/L vs 3.81 ± 1.16 mmol/L (P = 0.05); and free choline,1.07 ± 0.23 mmol/L vs 0.65 ± 0.20 mmol/L (P = 0.00). However,there was no statistical signif icance between the two groups. The hepatic sinus and cellular structure of hepatic cells in treatmentgroup were abnormal. Apoptosis of hepatic cells was confi rmed by TUNEL assay. CONCLUSION: High dose selenium compounds can cause the rat liver lesion and induce cell apoptosis in vivo. High resolution 1H-MRS in vitro can detect diversified metabolism. The changing trend for different ingredient of choline compounds is not completely the same at early period of apoptosis.展开更多
AIM To establish a cell culture system with long-term replication of hepatitis C virus in vitro.``METHODS Human hepatoma cell line 7721 was tested for its susceptibility to HCV by incubating with a serum from a patien...AIM To establish a cell culture system with long-term replication of hepatitis C virus in vitro.``METHODS Human hepatoma cell line 7721 was tested for its susceptibility to HCV by incubating with a serum from a patient with chronic hepatitis C. Cells and supernatant were harvested at various phases during the culturing periods The presence of HCV RNA, the expression of HCV antigens in cells and/or supernatant were examined by RT-PCR, in situ hybridization and immunohistochemistry respectively.``RESULTS The intracellular HCV RNA was first detected on d 2 after infection and then could be intermittently detected in both cells and supernatant over a period of at least three months. The expression of HCV NS3, CP10antigens could be observed in cells. The fresh cells could be infected by supematant from cultured infected cells and the transmission of viral genome from HCV-infected 7721 cells to PBMCs was also observed.``CONCLUSION The hepatoma line 7721 is not only susceptible to HCV but also supports its long-term replication in vitro.展开更多
AIM To evaluate antihepatoma effect ofantisense phosphorothioate oligodeo-xyribonucleotides (S-ODNs) targeted to alpha-fetoprotein (AFP) genes in vitro and in nudemice.METHODS AFP gene expression was examinedby immuno...AIM To evaluate antihepatoma effect ofantisense phosphorothioate oligodeo-xyribonucleotides (S-ODNs) targeted to alpha-fetoprotein (AFP) genes in vitro and in nudemice.METHODS AFP gene expression was examinedby immunocytochemical method or enzyme-linked immunosorbent assay. Effect of S-ODNson SMMC-7721 human hepatoma cell growth invitro was determined using microculturetetrazolium assay. In vivo antitumor activitiesof S-ODNs were monitored by measuring tumorweight differences in treated and control micebearing SMMC-7721 xenografts. Induction of cellapoptosis was evaluated by fluorescence-activated cell sorter (FACS) analysis.RESULTS Antisense S-ODN treatment led toreduced AFP gene expression. Specificantisense S-ODNs, but not control S-ODNs,inhibited the growth of heaptoma cells in vitro.In vivo. only antisense S-ODNs exhibitedobvious antitumor activities. FACS analysisrevealed that the growth inhibition by antisenseS. ODNs was associated with their cell apoptosisinduction.CONCLUSION Antisense S-ODNs targeted toAFP genes inhibit the growth of human hepatomacells and solid hepatoma, which is related totheir cell apoptosis induction.展开更多
Various liver diseases result in terminal hepatic failure, and liver transplantation, cell transplantation and artificial liver support systems are emerging as effective therapies for severe hepatic disease. However, ...Various liver diseases result in terminal hepatic failure, and liver transplantation, cell transplantation and artificial liver support systems are emerging as effective therapies for severe hepatic disease. However, all of these treatments are limited by organ or cell resources, so developing a sufficient number of functional hepatocytes for liver regeneration is a priority. Liver regeneration is a complex process regulated by growth factors (GFs), cytokines, transcription factors (TFs), hormones, oxidative stress products, metabolic net- works, and microRNA. It is well-known that the function of isolated primary hepatocytes is hard to maintain; when cultured in vitro, these cells readily undergo dedifferentia- tion, causing them to lose hepatocyte function. For this mason, most studies focus on inducing stem cells, such as embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), hepatic progenitor cells (HPCs), and mesenchymal stem cells (MSCs), to differentiate into hepatocyte-like cells (HLCs) in vitro. In this review, we mainly focus on the nature of the liver regeneration process and discuss how to main- tain and enhance in vitro hepatic function of isolated primary hepatocytes or stem cell-derived HLCs for liver regenera- tion. In this way, hepatocytes or HLCs may be applied for clinical use for the treatment of terminal liver diseases and may prolong the survival time of patients in the near future.展开更多
Coronavirus disease 2019(COVID-19),caused by the highly pathogenic severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),primarily impacts the respiratory tract and can lead to severe outcomes such as acute resp...Coronavirus disease 2019(COVID-19),caused by the highly pathogenic severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),primarily impacts the respiratory tract and can lead to severe outcomes such as acute respiratory distress syndrome,multiple organ failure,and death.Despite extensive studies on the pathogenicity of SARS-CoV-2,its impact on the hepatobiliary system remains unclear.While liver injury is commonly indicated by reduced albumin and elevated bilirubin and transaminase levels,the exact source of this damage is not fully understood.Proposed mechanisms for injury include direct cytotoxicity,collateral damage from inflammation,drug-induced liver injury,and ischemia/hypoxia.However,evidence often relies on blood tests with liver enzyme abnormalities.In this comprehensive review,we focused solely on the different histopathological manifestations of liver injury in COVID-19 patients,drawing from liver biopsies,complete autopsies,and in vitro liver analyses.We present evidence of the direct impact of SARS-CoV-2 on the liver,substantiated by in vitro observations of viral entry mechanisms and the actual presence of viral particles in liver samples resulting in a variety of cellular changes,including mitochondrial swelling,endoplasmic reticulum dilatation,and hepatocyte apoptosis.Additional ly,we describe the diverse liver pathology observed during COVID-19 infection,encompassing necrosis,steatosis,cholestasis,and lobular inflammation.We also discuss the emergence of long-term complications,notably COVID-19-related secondary sclerosing cholangitis.Recognizing the histopathological liver changes occurring during COVID-19 infection is pivotal for improving patient recovery and guiding decision-making.展开更多
A new thermokinetic reduced extent method for studying of the reversible competitive inhibition of single sub-strate enzyme-catalyzed reactions was proposed in this paper. The reaction that arginase-catalyzed hydrolys...A new thermokinetic reduced extent method for studying of the reversible competitive inhibition of single sub-strate enzyme-catalyzed reactions was proposed in this paper. The reaction that arginase-catalyzed hydrolysis of L-arginine to L-ornithine and urea and the inhibition of this reaction by the product, L-ornithine, and exogenous L-lysine were studied at 37 ℃ in 40 mmolL-1 sodium barbiturate-HCl buffer solution (pH=9.4). Michealis con-stant Km for arginine and maximum velocity Vm of the reaction were determined to be 5.14 mmolL-1 and 1.13× 10-2 mmolL-1s-1, respectively. The product inhibition constant KP and inhibitory constant KI of L-lysine were de-termined to be 1.18 and 5.6 mmolL-1, respectively. All the results have better repeatability and self-consistency and are in agreement with literature values. This new method using more direct thermal information from the proc-ess would give more reliable kinetic information than the traditional initial rate method.展开更多
The bovine liver candidate reference material specially for micro analytical techniques was prepared. The preparation process including material collection, dried, pulverize, sieve, homogenization and preliminary tes...The bovine liver candidate reference material specially for micro analytical techniques was prepared. The preparation process including material collection, dried, pulverize, sieve, homogenization and preliminary test was described in detail. The more effective grinding methods were established to achieve the median particle size of 22μm.展开更多
文摘<span style="font-family:Verdana;">The aim of this study was to investigate the effect of time o</span><span style="font-family:Verdana;">n</span> <i><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"></span></i><span style="font-family:Verdana;"> maturation of bovine oocytes and of the addition of follicular fluid on meiotic progression. The cumulus-oocyte complexes (COCs) collected from 3 to 6 mm follicles were obtained from ovaries of slaughtered female animals. The medium of maturation was supplemented or not with 20 μL follicular fluid (FF);661 oocytes were matured </span><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"> (extrusion of the first polar corpuscle) for 22 hours with </span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">added </span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">follicular fluid (AFF) (72.01%) or without follicular fluid (WFF) (67.53%) and 679 oocytes were matured <i></i></span><i><i><span style="font-family:Verdana;">in vitro</span></i></i><span style="font-family:Verdana;"></span><span style="font-family:Verdana;"> for 26 hours (extrusion of the first polar corpuscle) with AFF (92.1%) and WFF (77.15%). The results of extrusion of the second polar corpuscle as an event related to the fertilization percentages showed that the increase in the fertilization rate is maintained at 26 hours with AFF (79.45%), but the percentage decreases WFF (65.08%). After 22 hours, the fertilization rate was 62.38% AFF and 53.40% WFF. The developmental competence of bovine oocytes is affected by the duration of maturatio</span><span style="font-family:Verdana;">n </span><i><i><i><i><span style="font-family:Verdana;">in vitro</span></i></i></i></i><span style="font-family:Verdana;"></span><span style="font-family:Verdana;"> and the inclusion in the FF culture medium. The use of follicular fluid in th</span><span style="font-family:Verdana;">e </span><i><i><i><i><i><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"><i></i></span><i><span> </span></i></i></i></i></i></i><span style="font-family:Verdana;"></span><span style="font-family:Verdana;"></span><span></span><span style="font-family:Verdana;">maturation medium may be a biological strategy to increase the cumulus expansion, the nuclear maturation and the</span><i><i><i><i><i><i><span style="font-family:Verdana;"> <i></i></span><i><i><span style="font-family:Verdana;">in vitro</span></i><span style="font-family:Verdana;"><i> </i></span></i></i></i></i></i></i></i><span style="font-family:Verdana;"></span><span style="font-family:Verdana;"></span><span style="font-family:Verdana;">fertilization.</span></span></span></span>
基金This study was supported by grants from the Chinese Health Ministry (Funds supplement 75-62-03-29-05).
文摘Trinitrotoluene (TNT) increased the formation of adrenochrome from adrenaline and the formation of formaldehyde from methanol in rat liver mitochondria and microsomes in vitro as well as in monkey liver mitrochondria and microsomes in vivo. The effects were more prominent at higher TNT concentrations. These findings indicate that TNT enhances the production of superoxide radicals (O_2^-) and hydrogen peroxide (H_2O_2). The production of O_2^- was more prominent in systems containing added TNT than in those containing added benzyl viologen. H_2O_2 production by mitochondria was more pronounced in the liver than in other organs, but its production by microsomes was more pronounced in the brain than in other organs. The results suggest that TNT undergoes cycling reduction which produces oxidative stress. 1989 Academic Press, Inc.
基金Supported by the Innovation Team of the Beijing University of Chinese Medicine,No.2019-JYB-TD-006the National Natural Science Foundation of China,No.81873099Scientific Research Support Plan for the Construction of Doctoral Program of University of Tibetan Medicine.
文摘BACKGROUND Liver fibrosis is a common health problem worldwide and there is still a lack of effective medicines.The Chinese herbal medicine,Gan Shen Fu Fang(GSFF)is composed of salvianolic acid B and diammonium glycyrrhizinate.In this study,we observed the effects of GSFF on liver fibrosis in vivo and in vitro in an attempt to provide some hope for the treatment.AIM To observe the effects of GSFF on liver fibrosis in vivo and in vitro and investigate the mechanism from the perspective of the inflammatory response and extracellular signal-regulated kinase(ERK)phosphorylation.METHODS Common bile duct-ligated rats were used for in vivo experiments.Hepatic stellate cells-T6(HSC-T6)cells were used for in vitro experiments.Hematoxylin and eosin staining and Masson staining,biochemical assays,hydroxyproline(Hyp)assays,enzyme-linked immunoasorbent assay and western blotting were performed to evaluate the degree of liver fibrosis,liver function,the inflammatory response and ERK phosphorylation.The CCK8 assay,immunofluorescence and western blotting were applied to test the effect of GSFF on HSC-T6 cell activation and determine whether GSFF had an effect on ERK phosphorylation in HSC-T6 cells.RESULTS GSFF improved liver function and inhibited liver fibrosis in common bile ductligated rats after 3 wk of treatment,as demonstrated by histological changes,hydroxyproline assays and collagen I concentrations.GSFF alleviated inflammatory cell infiltration and reduced the synthesis of pro-inflammatory cytokines[tumor necrosis factor-α(TNF-α)and interlukin-1β]and NF-κB.In addition,GSFF decreased ERK phosphorylation.In vitro,GSFF inhibited the viability of HSC-T6 cells with and without transforming growth factorβ1(TGF-β1)stimulation and decreased the synthesis of collagen I.GSFF had the greatest effect at a concentration of 0.5μmol/L.GSFF inhibited the expression ofα-smooth muscle actin(α-SMA),a marker of HSC activation,in HSC-T6 cells.Consistent with the in vivo results,GSFF also inhibited the phosphorylation of ERK and downregulated the expression of NF-κB.CONCLUSION GSFF inhibited liver fibrosis progression in vivo and HSC-T6 cell activation in vitro.These effects may be related to an alleviated inflammatory response and downregulated ERK phosphorylation.
基金supports from General Program from the National Natural Science Foundation of China(No.31871016)the National Key Research and Development Program(2016YFC1101302)from the Ministry of Science and Technology of China.
文摘Liver injury is a common cause of drug approval withdrawal during drug development,pre-clinical research,and clinical treatment.If not properly treated,patients with severe liver injury can suffer from acute liver failure or even death.Thus,utilization of the convenient in vitro hepatotoxicity assessment model for early detection of drug-induced hepatotoxicity is vital for drug development and safe personalized medication.Biomaterials(e.g.,hydrogels,nanofibers,decellularized liver matrix)and bioengineering technologies(e.g.,microarrays,micropatterns,3D printing,and microfluidics)have been applied for in vitro hepatotoxicity assessment models.This review summarizes the structure and functions of the liver as well as the components of in vitro hepatotoxicity assessment models.In addition,it highlights the latest advances in developing hepatotoxicity models with the ultimate goal of further clinical translation.
基金supported by the Scientific Research & Development Fund of Tianjin Agricultural University
文摘[ Objective] To investigate the optimal culture system for in vitro fertilization (IVF) of oocyte in bovine. [ Method] The IVF of mature bovine oocytes was conducted and the fertilized eggs were cultured in vitro with different culture systems. In the traditional culture system, the TALP medium and BO medium were used as fertilization medium, respectively; and M-199 medium supplemented with 5% FCS was used as fertilized egg culture medium. In the transitional culture system, the TALP medium and BO medium were used as fertilization medium; 60% TALP and 40% M-199 supplemented with 5% FCS and 60% BO and 40% M-199 supplemented with 5% FCS were used as fertilized egg culture medium, respectively. The effects of different culture systems on fertilization rate and cleavage rate were observed. E Result] In the transitional culture system (with TALP medium as fertilization medium and with 60% TALP and 40% M-199 supplemented with 5% FCS as fertilized egg culture medium), the fertilization rate and cleavage rate were increased to 77.8% and 55.6%, respectively. [ Conclusion] The transitional culture system (with TALP medium as fertilization medium and with 60% TALP and 40% M-199 supplemented with 5% FCS as fertilized egg culture medium) is the optimal culture system for IVF of bovine oocyte.
文摘Heat stress is one of the main reasons for reproductive performance decrease in cattle, resulting in severe economic losses. The aim of this study was to evaluate the effect of heat stress during maturation, fertilization and development of in vitro produced bovine embryos. Cumulus oocyte complexes (COCs) were obtained by follicular puncture from slaughterhouse ovaries and after identification, were divided into four groups: control (CG), exposed 1 (EG1), exposed 2 (EG2), and exposed 3 (EG3). The oocytes of the group CG and CG3 were cultured at 38°C and the oocytes of group EG1 and EG2 were cultured at 40°C during the maturation period (24 hours at 5% CO2 in air). After the maturation period, oocytes of group CG, EG1, EG2, and EG3 were fecundated with frozen thawed semen. The oocytes of CG, EG2 and EG3 groups were cultured at 38°C, and the group EG1 was cultured at 40°C (18 hours at 5% CO2 in air). After that, the CG and EG2 groups were cultured in SOF at 38°C and the groups EG1 and EG3 at 40°C during embryonic development. The embryos were evaluated for cleavage, morula and blastocyst rates by optical microscopy. In control (CG) and EG3 groups, the oocytes showed uniform expansion of cumulus cells, classified as moderate to high, with brown color and uniform appearance of the ooplasm. In the oocytes exposed to 40°C (EG1 and EG2) we observed a decrease in the expansion of cumulus cells, and the same showed rounded appearance and retraction of the ooplasm with dark coloration. The control group (CG) had 68.23% ± 2% of cleavage, 50.16% ± 2% morulas, and 43.28% ± 1% blastocysts. Whereas the EG2 had 31.46% ± 2% cleavage, 35.64% ± 2% morula, and no blastocysts development. The EG3 had 3.7% ± 2% cleavage, and no embryo production. These data suggest that in all stages of exposure to heat stress, the embryos and the gametes are susceptible, leading to a decrease in embryonic development.
文摘AIM To investigate the effects of taxol onSMMC-7721 human hepatoma and itsmechanisms.METHODS In vitro cell growth was assessedby trypan blue exclusion method.Experimentalhepatoma model was established by seedingSMMC-7721 cells subcutaneously into Balb/c(nu/nu)nude mice.In vivo tumor growth wasdetermined by measurement of tumor diameterwith Vernier calipers.The syntheses of DNA,RNA and protein were analyzed by incorporationof ~3H-thymidine,~3H-uridine and ~3H-leucinerespectively.Using light and electronmicroscopes to observe the morphologicalchanges of cells including mitosis andapoptosis.RESULTS Taxol was effective against SMMC-7721 human hepatoma cell growth in the rangesof 2.5 nmol/L-10 nmol/L with mitotic arrestand apoptosis in vitro.DNA,RNA and proteinsyntheses in cells were also obviouslysuppressed by in vitro treatment of taxol for72 h.Taxol at 2.5 nmol/L reduced ~3H-thymidineuptake to about 34% of the control value(P【0.05).Increasing the dose of taxol to20 nmol/L resulted in a greater decrease in ~3H-thymidine incorporation to 60% of the controlvalue(P【0.01).At a concentration of 20 nmol/L,the ~3H-uridine and ~3H-leucine uptakeswere reduced to 52%(P【0.05)and 63%(P【0.01),respectively.In vivo,taxolsignificantly inhibited SMMC-7721 tumor growthat 10 mg/kg,i.p.,once daily for 10 d.A morethan 90% decrease in tumor volume wasobserved by day 11(P【0.01)similarly withmitotic arrest and cell apoptosis.CONCLUSION Taxol has a marked anticanceractivity in SMMC-7721 human hepatoma both invitro and in nude mice.Its mechanisms might beassociated with mitotic arrest,subsequently,apoptosis of the hepatoma cells.No obvioustoxicity was observed with in vivoadministration of taxoi.
文摘The use of an internal control in a multiplex-PCR assay for sex determination of In Vitro-produced bovine embryos was evaluated in biopsies of groups of 54 fresh and 44 frozen embryos. The internal controls used were the primers BOV 1 and BOV 2, which amplify a product with 626 base pairs (bp) of bovine mitochondrial DNA ND5 gene. The primers BRY.4aF and BRY.4aR were used for bovine Y chromosome sequence amplification. The specificity of multiplex- PCR reactions realized in biopsies corresponding to about 20% of each fresh embryo (10 male and 10 female) by means of confirming the sexing in the remaining embryo content (~80%) presented 100% specificity. Amplicons of the internal control and Y chromosome were both amplified until dilution corresponding to 6.25% of total extracted DNA from a male embryo. Sex determination was possible in 53 (98.1%) fresh embryos and 40 (90.9%) frozen embryos. The products related to the Y chromosome and mitochondrial DNA were simultaneously amplified in 34 (63%) fresh embryos and 27 (61.4%) frozen embryos, showing a male embryo. The female sex, distinguished by internal control amplification only, was detected in 19 (35.2%) and 13 (29.5%) biopsies, respectively, of fresh and frozen embryos. In one (1.8%) and four (9.1%) biopsies of fresh and frozen embryos, respectively, neither product was amplified, most likely due to the absence of embryonic cells or the presence of embryonic cells going through apoptosis. The multiplex-PCR assay developed in this work showed avoided the limitation of a lack of an internal standard, and was also sensitive, specific, and efficient in reaction failure identification. This technique shows great potential for use on a commercial scale in routine sex determination of In Vitro-produced embryos.
文摘Olmesartan Medoxomil (OLM), Ramipril (RPL) & Fenofibric acid (FA) are used to treat hypertension and cardiovascular disease. These drugs undergo hydrolytic metabolism by the enzyme liver esterase and converts into their respective active metabolites Olmesartan (OL), Ramiprilat (RPT) and Fenofibric acid (FA) for OLM, RPL and FEN respectively. In this study the competitive metabolism of OLM, in presence of RPL and FEN was investigated in rat liver s9 fractions using a validated LC-MS method. Olmesartan Medoxomil was found to be highly reactive to the rat liver S9 fractions and formation of active metabolite Olmesartan is highest. The rate of formation of active metabolite Olmesartan reduced by 12.68% in the presence Ramipril and 6.56% in presence of Fenofibrate. A marked reduction of 18.96% was found in the formation of active metabolite Olmesartan from Olmesartan Medoxomil when all the three drugs are in combination.
文摘The in vitro maturation, fertilization and development of bovine ovary oocytes in two differentcultural systems A and B were studied under the conditions of 38.5℃,5%CO2,95%air and 100%humidity.The maturation rates were 94.5%and 91.3%,respectively,and the difference wasextremely significant.Frozen semen were thawed and sperm were capacitated with three kinds ofcapacitation agents for fertilization.The pronucleus rates were 76%,65%-68%and 62%respectively.The rates of embryos developed to morula and blastocyst were 19%,16% and 17%respectively.The developmental rates of embryos cocultured with bovine oviductal epithelium cellsand bovine granulosa cells were 25% and 23.4% respectively,with no significant difference. Freshembryos were transplanted into 15 recipicns,and three of them were pregnant and calves were bornin 1990 and 1991.The pregnant rate was 20%.The emryos developed faster before 8-cell stage andslower after 8-cell stage,in vitro than in vivo.
文摘It has been recognized that alpha-fetoprotein (AFP),as an oncofetal antigen, re-expresses in large amounts inadult tumor cells and serves clinically useful purposes asa tumor marker assay. However, its biological activiticsare still far from clear. In thc present study, the ability ofAFP to stimulate tumor cell growth was observed by invitro test system. The new finding indicates that AFPcontributes to the generation and development of tumorand is an important target action site of tumor therapy.
基金This research was supported by the National Natural Science Foundation of China(30370743,90408002)National Science Found for Distin-guished Young Scholars of China(30225006)Supported by Program for Changjiang Scholars and Innovative Re-search Team in University(PCSIRT).
文摘Various systems by using electric pulse, calcium, or polyethylene glycol have been developed in the past decade for the in vitro fusion of plant gametes. These in vitro systems provide a new way to study the fertilization mechanisms of plants. In this study, we developed a bovine serum albumin (BSA)-mediated fusion system for the in vitro fusion of maize gametes. The in vitro fusion of the isolated single egg cell and sperm cell of maize was observed microscopically in the BSA solution and the fertilized egg cell showed normal cell wall regeneration and nuclear division. The effects of the BSA concentration, pH value and calcium level on the efficiency of the maize gamete fusion were also assessed. BSA concentration and pH value did significantly affect the efficiency of the gamete fusion. Calcium was not necessary for the gamete fusion when BSA was present. The optimal solution for the gamete fusion contained 0.1% BSA, pH 6.0. The fusion frequency was as high as 96.7% in that optimal solution. This new in vitro fertilization system offers an alterna- tive tool for the in vitro study of fertilization mechanisms with much simpler manipulating procedure than PEG system, and it will be especially useful for the in vitro study of the calcium dynamics during plant fertilization.
基金The National Natural Science Foundation of China,No.30570480
文摘AIM: To study liver cell apoptosis caused by the toxicity of selenium and observe the alteration of choline compounds using in vitro 9.4T high resolution magnetic resonance spectroscopy. METHODS: Twenty male Wistar rats were randomly divided into two groups. The rats in the treatment group were intraperitoneally injected with sodium selenite and the control group with distilled water. All rats were sacrifi ced and the livers were dissected. 1H-MRS data were collected using in vitro 9.4T high resolution magnetic resonance spectrometer. Spectra were processed using XWINNMR and MestRe-c 4.3. HE and TUNEL staining was employed to detect and confi rm the change of liver cells. RESULTS: Good 1H-MR spectra of perchloric acid extract from liver tissue of rats were obtained. The conventional metabolites were detected and assigned. Concentrations of different ingredient choline compounds in treatment group vs control group were as follows: total choline compounds,5.08 ± 0.97 mmol/L vs 3.81 ± 1.16 mmol/L (P = 0.05); and free choline,1.07 ± 0.23 mmol/L vs 0.65 ± 0.20 mmol/L (P = 0.00). However,there was no statistical signif icance between the two groups. The hepatic sinus and cellular structure of hepatic cells in treatmentgroup were abnormal. Apoptosis of hepatic cells was confi rmed by TUNEL assay. CONCLUSION: High dose selenium compounds can cause the rat liver lesion and induce cell apoptosis in vivo. High resolution 1H-MRS in vitro can detect diversified metabolism. The changing trend for different ingredient of choline compounds is not completely the same at early period of apoptosis.
基金Suppprted by the Mational Natural Science Foundation of China,No.39670672.
文摘AIM To establish a cell culture system with long-term replication of hepatitis C virus in vitro.``METHODS Human hepatoma cell line 7721 was tested for its susceptibility to HCV by incubating with a serum from a patient with chronic hepatitis C. Cells and supernatant were harvested at various phases during the culturing periods The presence of HCV RNA, the expression of HCV antigens in cells and/or supernatant were examined by RT-PCR, in situ hybridization and immunohistochemistry respectively.``RESULTS The intracellular HCV RNA was first detected on d 2 after infection and then could be intermittently detected in both cells and supernatant over a period of at least three months. The expression of HCV NS3, CP10antigens could be observed in cells. The fresh cells could be infected by supematant from cultured infected cells and the transmission of viral genome from HCV-infected 7721 cells to PBMCs was also observed.``CONCLUSION The hepatoma line 7721 is not only susceptible to HCV but also supports its long-term replication in vitro.
基金Supported by the National Postdoctoral Science Foundation of China,No.199711.
文摘AIM To evaluate antihepatoma effect ofantisense phosphorothioate oligodeo-xyribonucleotides (S-ODNs) targeted to alpha-fetoprotein (AFP) genes in vitro and in nudemice.METHODS AFP gene expression was examinedby immunocytochemical method or enzyme-linked immunosorbent assay. Effect of S-ODNson SMMC-7721 human hepatoma cell growth invitro was determined using microculturetetrazolium assay. In vivo antitumor activitiesof S-ODNs were monitored by measuring tumorweight differences in treated and control micebearing SMMC-7721 xenografts. Induction of cellapoptosis was evaluated by fluorescence-activated cell sorter (FACS) analysis.RESULTS Antisense S-ODN treatment led toreduced AFP gene expression. Specificantisense S-ODNs, but not control S-ODNs,inhibited the growth of heaptoma cells in vitro.In vivo. only antisense S-ODNs exhibitedobvious antitumor activities. FACS analysisrevealed that the growth inhibition by antisenseS. ODNs was associated with their cell apoptosisinduction.CONCLUSION Antisense S-ODNs targeted toAFP genes inhibit the growth of human hepatomacells and solid hepatoma, which is related totheir cell apoptosis induction.
文摘Various liver diseases result in terminal hepatic failure, and liver transplantation, cell transplantation and artificial liver support systems are emerging as effective therapies for severe hepatic disease. However, all of these treatments are limited by organ or cell resources, so developing a sufficient number of functional hepatocytes for liver regeneration is a priority. Liver regeneration is a complex process regulated by growth factors (GFs), cytokines, transcription factors (TFs), hormones, oxidative stress products, metabolic net- works, and microRNA. It is well-known that the function of isolated primary hepatocytes is hard to maintain; when cultured in vitro, these cells readily undergo dedifferentia- tion, causing them to lose hepatocyte function. For this mason, most studies focus on inducing stem cells, such as embryonic stem cells (ESCs), induced pluripotent stem cells (iPSCs), hepatic progenitor cells (HPCs), and mesenchymal stem cells (MSCs), to differentiate into hepatocyte-like cells (HLCs) in vitro. In this review, we mainly focus on the nature of the liver regeneration process and discuss how to main- tain and enhance in vitro hepatic function of isolated primary hepatocytes or stem cell-derived HLCs for liver regenera- tion. In this way, hepatocytes or HLCs may be applied for clinical use for the treatment of terminal liver diseases and may prolong the survival time of patients in the near future.
文摘Coronavirus disease 2019(COVID-19),caused by the highly pathogenic severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),primarily impacts the respiratory tract and can lead to severe outcomes such as acute respiratory distress syndrome,multiple organ failure,and death.Despite extensive studies on the pathogenicity of SARS-CoV-2,its impact on the hepatobiliary system remains unclear.While liver injury is commonly indicated by reduced albumin and elevated bilirubin and transaminase levels,the exact source of this damage is not fully understood.Proposed mechanisms for injury include direct cytotoxicity,collateral damage from inflammation,drug-induced liver injury,and ischemia/hypoxia.However,evidence often relies on blood tests with liver enzyme abnormalities.In this comprehensive review,we focused solely on the different histopathological manifestations of liver injury in COVID-19 patients,drawing from liver biopsies,complete autopsies,and in vitro liver analyses.We present evidence of the direct impact of SARS-CoV-2 on the liver,substantiated by in vitro observations of viral entry mechanisms and the actual presence of viral particles in liver samples resulting in a variety of cellular changes,including mitochondrial swelling,endoplasmic reticulum dilatation,and hepatocyte apoptosis.Additional ly,we describe the diverse liver pathology observed during COVID-19 infection,encompassing necrosis,steatosis,cholestasis,and lobular inflammation.We also discuss the emergence of long-term complications,notably COVID-19-related secondary sclerosing cholangitis.Recognizing the histopathological liver changes occurring during COVID-19 infection is pivotal for improving patient recovery and guiding decision-making.
基金Project supported by the National Natural Science Foundation of China (No. 30070200) and the Major Project of Hubei Province Department of Education China (No. 2003A009).
文摘A new thermokinetic reduced extent method for studying of the reversible competitive inhibition of single sub-strate enzyme-catalyzed reactions was proposed in this paper. The reaction that arginase-catalyzed hydrolysis of L-arginine to L-ornithine and urea and the inhibition of this reaction by the product, L-ornithine, and exogenous L-lysine were studied at 37 ℃ in 40 mmolL-1 sodium barbiturate-HCl buffer solution (pH=9.4). Michealis con-stant Km for arginine and maximum velocity Vm of the reaction were determined to be 5.14 mmolL-1 and 1.13× 10-2 mmolL-1s-1, respectively. The product inhibition constant KP and inhibitory constant KI of L-lysine were de-termined to be 1.18 and 5.6 mmolL-1, respectively. All the results have better repeatability and self-consistency and are in agreement with literature values. This new method using more direct thermal information from the proc-ess would give more reliable kinetic information than the traditional initial rate method.
文摘The bovine liver candidate reference material specially for micro analytical techniques was prepared. The preparation process including material collection, dried, pulverize, sieve, homogenization and preliminary test was described in detail. The more effective grinding methods were established to achieve the median particle size of 22μm.