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BACKGROUND:Establishing a stable and reliable animal model of acute pancreatitis is of great significance for understanding its pathogenesis,pathophysiological characteristics,and clinical medication.Domestic and foreign studies have shown that cerulein,L-arginine,and sodium taurocholate can induce acute pancreatitis,but their pathophysiological characteristics and model characteristics are still unclear. OBJECTIVE:To establish an acute pancreatitis rat model using cerulein,L-arginine,and sodium taurocholate and to observe the changing patterns of model features at different time points. METHODS:Ninety-six healthy male Sprague-Dawley rats were randomly divided into normal group,cerulein group,L-arginine group,and sodium taurocholate group,with 24 rats in each group.Within each group,there were three subgroups(n=8 per group):12-,24-,and 48-hour subgroups.Cerulein was administered via intraperitoneal injection six times with a 1-hour interval.L-arginine was administered through two intraperitoneal injections with a 1-hour interval.Sodium taurocholate was injected for inducing acute pancreatitis models through retrograde injection into the bile-pancreatic duct.By examining the rat survival rate,gross morphology of the pancreas,calculating the pancreatic organ index,and measuring levels of amylase,lipase,alanine transaminase,aspartate transaminase,blood urea nitrogen,and creatinine,as well as observing pancreatic tissue pathological features through hematoxylin-eosin staining and conducting a pancreatic injury scoring,we evaluated the changing patterns of model features at different time points. RESULTS AND CONCLUSION:Compared with the normal group,the overall survival rate of rats was 100%in the cerulein group,88%in the L-arginine group,and 96%in the sodium taurocholate group.The pancreatic organ index was increased in all groups.Gross observation indicated that,In the cerulein group,pancreatic edema,blurred lobes,and looseness were visible.In the L-arginine group,the pancreatic glands were enlarged and thickened with patchy bleeding.In the sodium taurocholate group,pancreatic tissue showed varying degrees of congestion and edema accompanied by scattered flakes of hemorrhage and necrosis.The levels of serum alanine transaminase,aspartate transaminase,blood urea nitrogen,creatinine,amylase,and lipase in rats exhibited consistent changes.In the cerulein group,these parameters possibly peaked at 12 hours(P<0.05)and then showed a declining trend.In the L-arginine group,they reached the highest levels at 24 hours(P<0.05)and significantly decreased at 48 hours.In the sodium taurocholate group,serum amylase and lipase remained at higher levels at 12 hours with a slow decline trend(P<0.05).Compared with the normal group,microscopic examination revealed mild acinar edema and widened interlobular spaces in the cerulein group,with a higher presence of inflammatory cells.In the L-arginine group,there was widening of interlobular spaces,extensive infiltration of inflammatory cells,and patchy necrotic areas.In the sodium taurocholate group,significant pancreatic edema,structural disarray,extensive necrotic foci,and inflammatory cell infiltration were observed.Compared with the normal group,the pathological scores of induced acute pancreatitis in all three models were significantly different at each time point(P<0.05).Moreover,the pathological scores in each group increased over time,indicating a gradual worsening of pancreatic tissue damage.When comparing different models at the same time,there were differences in pathological scores,with the sodium taurocholate group having the highest scores,followed by the L-arginine group,and the cerulein group having the lowest scores.Analyzing the three models at the same time point,the most severe condition was in the sodium taurocholate group,which was characterized by pancreatic hemorrhage and necrosis,followed by the L-arginine group,which was characterized by necrosis,and the least severe condition was in the cerulein group,mainly characterized by edema.The serum biochemical index levels of the cerulein and L-arginine groups decreased at 48 hours,indicating that these two models may have a tendency to self-heal and belong to a self-limiting disease course.The serum biochemical index levels of the sodium taurocholate group decreased slowly after 12 hours.Therefore,pancreatic injury in the sodium taurocholate group might not be relieved after 48 hours or longer.
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Objective To investigate the correlation between the residual cholesterol(RC)level and vertebrobasilar dilatation(VBD)in elderly patients with acute cerebral infarction(ACI).Methods A total of 325 elderly ACI patients admitted to Department of Neurology,Changzhou Second People's Hospital of Nanjing Medical University from January 2020 to July 2021 were recruited retrospectively.All of them underwent cranial MRI,CTA and biochemical test for plasma levels of TC,TG,LDL-C and HDL-C and other biochemical indicators.According to the imaging diagnostic criteria,they were divided into VBD group(52 cases)and non-VBD group(273 cases).Their clini-cal data were compared between the two groups,and the relationship between RC level and VBD was analyzed in the elderly ACI patients.Results Significant differences were observed in age,sex,hypertension,history of smoking and TC and RC levels between the VBD group and non-VBD group(P<0.05,P<0.01).Multivariate logistic regression analysis showed that after adjus-ting the potential confounding factors,age(OR=1.126,95%CI:1.065-1.191,P=0.000),male(OR=4.163,95%CI:11.173-10.120,P=0.002),and RC level(OR=1.270,95%CI:1.151-1.401,P=0.000)were independent risk factors for VBD in elderly ACI patients.Conclusion Age,male and RC level are independent risk factors for VBD in elderly ACI patients.High RC lev-el may increase the risk of VBD.
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Objective To find out whether NOTCH receptors can serve as direct downstream targets of transforming growth factor β(TGF-β)/Smad4 signaling in endothelial cells.Methods Real-time PCR and Western blotting were performed to verify whether the expression of notch1 and notch4 was regulated by TGF-β pathway.Luciferase reporter assay was employed to investigate how the promoter of notch1 and notch4 was regulated by TGF-β.Then, ChIP assay was used confirm whether the promoter of notch1 and notch4 physically interacted with SMAD protein.Results TGF-β1 and bone morphogenetic protein 4 (BMP4) treatment increased the expression of both notch1 and notch4 at the transcriptional level.In addition, SMAD4 was physically associated with the SMAD binding sites on the notch4 promoter, which was largely enhanced under the treatment of TGF-β1 and BMP4.Importantly, TGF-β1 and BMP4 failed to transactivate notch4 in the absence of endogenous SMAD4 or the SMAD binding regions on the notch4 promoter.Conclusion The expression of NOTCH receptor can be directly up-regulated by SMAD4-mediated TGF-β/BMP signaling in cerebrovascular endothelial cells.
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Objective To investigate the protective effect of fibrauretin injection against acute lung injury induced by lipopolysaccharide (LPS) in mice.Methods Seventy-two healthy male adult Kunming mice were randomly divided into 6 goups:normal control group,LPS group (intratracheal instilation of 5 mg/kg of LPS),hydrocortisone group (intraperitoneal injection of 3.3 mg/kg of hydrocortisone,once daily for 3 days,and intratracheal instilation of 5 mg/kg of LPS on the 4th day) and low dose,medium dose and high dose of fibrauretin groups (intraperitoneal injection of 2,10 and 50 mg/kg of fibrauretin,respectively,once daily for 3 days,and intratracheal instilation of 5 mg/kg of LPS on the 4th day).The mice in each group were sacrificed by dislocation 24 h after intratracheal instilation of LPS.The lung tissues of partial mice in each group were extracted and weighed to calculate the lung coefficients,and bronchoalveolar lavage (BAL) was performed in partial mice in each group to collect the BALF for counting the inflammatory cells.Results The lung cofficients of mice in LPS group were significantly higher than those in the normal control group (P<0.05).The lung cofficients of mice in hydrocortisone group,low dose,medium dose and high dose of fibrauretin groups were significantly lower than those in LPS group (P < 0.05).For the percentage of inflammatory cells in BALF and the percentage of neutrophils in inflammatory cells,LPS group was significantly higher than the normal control group (P<0.01),and compared with LPS group,hydrocortisone group,low dose,medium dose and high dose of fibrauretin groups were significantly decreased (P<0.01).Conclusion Fibrauretin injection can significantly ameliorate the inflammatory reaction degree in mice with acute lung injury induced by LPS.
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Objective To discuss whether mild hyperuricemia can lead to kidney damage and the protection of decreased uric acid,through observing that hyperuricemia did damage to glomerulus endothelial function and cell proliferation of vascular smooth muscle in rats. Methods Fifty-four male SD rats were divided into four groups,the control group,model group (Oxonate),allopurinol group and Oxonate+allopurinol group.Rats were administered on a low sodium diet and their systolic blood pressure (SBP) were measured each 10 days.ELISA was used to detect rat plasma markers of endothelial function damage [nitric oxide (NO),type-1 plasminogen activator inhibitor (PAI-1),endothelin 1 (ET-1)] and cell proliferation of vascular smooth muscle[plateletderived growth factor (PDGF),cycloxygenase 2 (COX2),monocyte chemotactic protein-1 (MCP-1)],and the markers of inflammatory reaction[interleukin-18 (IL-18),tumor necrosis factor α(TNF-α)].PDGF and nitric oxide synthase (NOS) levels of rats were detected by immunohistochemical method.Renal tissue pathology of rats was observed. Results Compared to the control group,the plasmic concentration of COX2,ET-1,IL-18,PAI-1,PDGF,TNF-o,MCP-1 increased,and NO decreased significantly in rats of model group (all P<0.05),expression of NOS significantly reduced and PDGF increased (all P<0.05).Under light microscope,vascular wall thickening,intimal proliferation and lumen slight stricture without uric acid crystals in renal tissue were found in model group,which were obviously improved by using allopurinol. Conclusion Mild hyperuricemia can do damage to endothelial function of glomerulus and lead to vascular cell proliferation,which can be improved through decreasing uric acid.
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Objective To analyze the composition and distribution of pathogens from 1366 superficial candidiasis cases in Shanghai.Methods Candida species identification was carried out for 1366 adults or children with superficial candidiasis by using CHROMagar Candida plates,API20C AUX system,etc.Pal's agar,Xylose assimilation and the test for growth at 45 ℃ were utilized to differentiate Candida dubliniensis.Newly identified pathogenic Candida species including Candida orthopsilosis,Candida metapsilosis,Candida fermentati,Candida nivariensis and Candida bracarensis were differentiated by molecular biological methods.Finally,the composition and distribution of pathogens in superficial candidiasis cases were statistically analyzed.Results A total of 1366 Candida strains,included 2 Candida orthopsilosis strains and 4 Candida metapsilosis strains,were isolated from these cases.Among these isolates,Candida albicans predominated(79.0%),followed by Candida parapsilosis(9.5%),Candida tropicalis(2.9%)and Candida guilliermondii(1.9%).The composition of Candida species was significantly different between child and adult patients(x2 =196.46,P < 0.01),with the isolation rate of non-albicans Candida species being 14.4% and 45.8% respectively in child and adult patients.Conclusions Candida albicans is still the dominant pathogen of superficial candidiasis.Candida orthopsilosis and Candida metapsilosis can cause superficial candidiasis.The isolation rote of non-albicans Candida species is higher in adult patients than in child patients.
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Objective To evaluate the role of Restriction fragment length polymorphism (RFLP) analysis in detection of the fragment of GEF1α/a gene which are both located at ct and a mating type loci in identification of species, varieties, genotypes and mating types of Cryptococcus neoformans species complex(Cryptococcus neoformans and Cryptococcus gattii). Methods The GEF1α/a gene was selected from 20 genes which both located at α and a mating type loci for RFLP analysis, according to the requirements of sequence similarities and primer design in PCR-RFLP analysis. Primer pair was designed from the conserved regions of GEF1α/a genes of distinct genotypes and mating types of reference strains to amplify a fragment of GEF1α/a gene from Cryptococcus neoformans and Cryptococcns gattii strains tested. Sequence alignment,restriction maps analysis, endonucleases selection and electrophoresis stimulation were conducted by using DNAMAN and Vector NTI software. EeoT14 Ⅰ and Hap Ⅱ endonucleases were selected for RFLP analysis of the GEF1α/a fragments amplified from 125 isolates of Cryptococcns neoformans and Cryptococcus gattii. Results An approximate 1 300 bp fragment was amplified from total 82 Cryptococcus neoformans and 43 Cryptoceccus gattii isolates. However, negative PCR results were found in the reference strains of Cryptococcus laurentii, Candida albicans, Candida tropicalis, Candida parapsilosis, Candida krnsei,Candida glabrata, Trichosporon asahii, Aspergillus fumigatns and Aspergillus flavus. RFLP analysis successfully identified the species, varieties, genotypes and mating types of total 125 isolates of Cryptococcus neoformans and Cryptococcns gattii tested in this study. Condusion PCR-RFLP analysis of the GEF1α/a fragment has the potential value in identification of species, varieties, genotypes and mating types of Cryptococeus neoformans species complex simultaneously and rapidly, and may be a useful tool in molecular epidemiological analysis.