Objective To investigate the protective effect of hydrogen sulfide (H2S) on chronic unpredictable mild stress (CUMS)-induced damage in hippocampus of rats and explore potential mechanisms.Methods 40 SD rats were divided into four groups,including controI,CUMS,CUMS co-treated with NaHS (1.68 mg/kg×14 d,ip) and CUMS co-treated with NaHS (5.6 mg/kg×14 d,ip) groups.After treatment with CUMS for 4 weeks,arrangement and morphology of hippocampal neuron were examined by HE staining,apoptosis of hippocampal neurons were measured by Tunel assay.Klotho expression was detected by ELISA.Meanwhile,the generation of H2S in the hippocampus was measured by spectrophotometry and the neurogenesis of hippocampus was detected by Brdu staining.Results The arrangement and morphology of CA3 hippocampal cells were disturbed and the neurogenesis in hippocampal DG region were inhibited in the CUMS group compared with control group.Moreover,the CUMS rats showed increased loss of hippocampal neurons (1.151±0.041,P＜0.01),and the expression of klotho(0.910±0.032) and generation of H2S((0.445± 0.025)nmol · mg-1 · min-1) in CUMS rats were decreased in contrast to the control((0.621±0.019) nmol · mg-1 · min-1,P＜0.05).The sparse neuron and inhibited neurogenesis by CUMS in hippocampus of rats were improved by NaHS administration,and the loss of hippocampal neurons in CUMS + 1.68 mg/kg NaHS (1.032±0.023) or CUMS +5.60 mg/kg NaHS(1.045±0.038) were decreased in contrast to the CUMS rats(P＜0.01).Compared with CUMS group,the expression of klotho in CUMS + 1.68 mg/kg NaHS group (1.045±0.021)or CUMS +5.6 mg/kg NaHS group(1.046±0.076) was up-regulated(P＜0.05) and the generation of H2S in CUMS + 1.68 mg/kg NaHS group((0.582±0.008) nmol · mg-1 · min-1) or CUMS +5.6mg/kg NaHS group ((0.585 ±0.029) nmol · mg-1 · min-1) was increased (all P＜0.05).Conclusion H2S can antagonize the neural injury-induced by chronic stress probably by upregulating the expression of klotho protein,facilitating the production of H2S and promoting neurogenesis in hippocampus.

Objective: To analyze the genetic characteristics of whole-genome and quasispecies sequences from three hepatitis A virus (HAV) strains in China. Methods: Serum samples from acute hepatitis A patients were collected and viral RNA extraction, transcription, nested PCR, sequencing and assembling were performed to gain near full-length sequences; cloning-based sequencing of the full-length VP1-2 A region was also performed. Results: Genotyping showed that the nucleotide and amino acid identities among three strains on VP1-2 A junction region were both 100% and all belonged to subgenotype IA; the nucleotide and amino acid identities on whole-genome region were 99.9%-100% and 100% respectively, and shared the highest identities with AH2 strain from GenBank of 98.5% in nucleotide and 99.7% in amino acid level; no amino acid variation was found among published neutralizing antigenic sites. Within cloning sequences from each strain, the nucleotide and amino acid identities were 99.0%-100% and 98.1%-100%, while among all cloning sequences were 99.0%-100% and 97.2%-100%. The variation rate of nucleotide and amino acid in VP1-2 A junction region were both higher than that of partial VP1 region. Conclusions Sequences among three strains in VP1-2 A region were identical, the nucleotide and amino acid identities in both whole-genome region and among quasispecies sequences were relatively high to deduce that they were from the same outbreak. This study provides new insight for identification of HAV transmissions and tracing investigations.

Objective:To observe and compare the radiographs of spiral CT and cone-beam CT (CBCT) in the imaging of temporomandibular joint osteoarthrosis (TMJOA) and to explore the difference between CBCT and spiral CT in detection accuracy so as to provide references for clinical diagnosis and treatment.Methods:A total of 52 patients with TMJOA diagnosed in the Department of Oral and Maxillofacial Surgery, General Hospital of Chinese PLA, from January 2018 to December 2019 were selected. There were 10 males and 42 females, with an average age of 38.6 years (21-70 years). All patients underwent spiral CT and CBCT examinations. Two oral radiologists and two oral and maxillofacial surgeons measured and evaluated the joint spaces and condylar bone lesions of each side of temporomandibular joint. According to the presence or absence of osteoarthrosis, the patients were divided into osteoarthrosis group (92 sides) and non osteoarthrosis group (12 sides). The mean size of joint spaces and the detection rate of lesions were compared between the two groups. SPSS 20.0 was used to analyze the data.Results:There was no significant difference between the measurements of joint space size and joint position in the spiral CT group and the CBCT group ( P>0.05). The mean size of the anterior space and the ratio of the posterior condyle in the osteoarthrosis side were larger than that in the normal side. The linear percentage index was smaller in the osteoarthrosis side than that in the normal side indicating that the position of the posterior condyle in the osteoarthrosis side was deviated. However, the difference was not statistically significant ( P>0.05). Both spiral CT and CBCT showed good consistency in displaying condylar osteopathy. The most common types of condylar osteopathy was surface defect. The detection rates of defects by spiral CT were surface erosion (85.6%, 89/104), articular surface flattening and shortening (82.7%, 86/104), subcortical sclerosis (40.4%, 42/104), osteophyte (40.4%, 42/104) and subcortical cyst (11.5%, 12/104) respectively. The detection rates of defects by CBCT were surface erosion (88.5%, 92/104), articular surface flattening and shortening (86.5%, 90/104), subcortical sclerosis (35.6%, 37/104), osteophyte (41.3%, 43/104) and subcortical cyst (11.5%, 12/104). There was no statistical difference between the two groups ( P>0.05), respectively. Conclusions:Both spiral CT and CBCT showed good accuracies in displaying the osteopathy of TMJOA and the sizes of the joint spaces measured by spiral CT and CBCT were basically the same. Both spiral CT and CBCT could be used as a routine diagnostic method for TMJOA.

Objective To compare concentration methods of ultrafiltration and PEG precipitation for hepatitis A virus( HAV) in simulated water samples, and provide a reference for detection of HAV in water. Methods Quantitative HAV was inoculated in the simulated water samples.Millipore, Sartorius, 100KD and 50KD aperture microporous ultrafiltration centrifuge tubes and the final concentration of 10%polyethylene glycol (PEG) -1M sodium chloride (NaCl) precipitation method were selected to concentrate HAV.The concentration of virus was detected by fluorescence quantitative RT-PCR method.The data were statistically analyzed with SPSS21.0.Results The comparison of CT value and recovery rate shows that there were significant differences in different treatment methods (P<0.0001, P<0.0001).There were not statistically significant between ultrafiltration centrifuge tubes that they produced by different factory but with the same aperture (P=0.25, P=0.532), 50KD group had a higher recovery rate(94.57 ±16.26%)than 100KD group (52.37 ±14.75%) and the 10%PEG-1.0MNaCl (63.5 ±8.45%) was in middle of them. Conclusions Both methods of ultrafiltration and PEG precipitation can be used for HAV concentration in water samples, the ultrafiltration centrifuge tube has the advantages of simple operation, less time-consuming and so on, select the appropriate aperture can improve the recovery rate of HAV virus.The HAV recovery rate of 50KD ultrafiltration centrifuge tube is higher than 100kD;PEG is more economical and practical, also it can process a large volume sample.

Objective:To analyze the characteristics of the whole genome of hepatitis A virus (HAV) strains from Nanchong, Sichuan and Hetian, Xinjiang.Methods:Serum samples of 9 patients with acute hepatitis A were selected for HAV whole genome sequencing. Among them, 3 were from the same outbreak in Nanchong, Sichuan (2006) and 6 were from Hetian, Xinjiang(2016). Nine full length HAV sequences were obtained by viral RNA extraction, reverse transcription, nested PCR and sequencing. Phylogenetic analysis, neutralizing epitope sites, recombination and natural selection analysis were also performed.Results:Genotyping of HAV VP1-2A region indicated that the 9 HAV sequences all belonged to sub-genotype IA and were divided into four different branches, with 3 Nanchong sequences and 3 Hetian sequences in the same branch. While the whole genome sequence showed that the nucleotide and amino acid homology of 3 Nanchong sequences were 99.99%~100% and 100%, respectively. The difference of nucleotides and amino acids were 0.50%~0.57% and 0.08%~0.17% between 3 Nanchong and 3 Hetian sequences, respectively. The nucleotide and amino acid identities of nine HAV genomes were 98.29%~100% and 99.62%~100%, which was closely related to hd9 in China and MNA12-001 in Mongolia (nucleotide and amino acid homology: with hd9 98.60%~99.50% and 99.75%~99.92%; and with MNA12-001 98.45%~99.32% and 99.71%~99.87%, respectively). The 9 HAV sequences did not change at the neutralizing epitope sites, and no recombination events were found. Natural selection analysis indicated that the HAV coding region was subjected to a negative selection.Conclusions:There are many HAV epidemic strains in China; the 9 HAV amino acid sequences were conserved at the major neutralizing epitope sites.

Objective:To compare the four nucleic acid detection method of hepatitis A virus.Methods:Using method A, B, and C real-time fluorescent quantitative RT-PCR(RT-qPCR)and method D droplet chip digital PCR(RT-dPCR)to detect the sensitivity of HAV plasmid and gradient dilution HAV vaccine respectively. Specific detection of related viral nucleic acid was performed. Methods A, B, and C were used to detect 40 artificially contaminated HAV oysters, commercially available oysters and serum samples, and HAV vaccine samples, and compare the detection rates. The recovery rates of method A and D on artificially contaminated oysters were compared with low concentration of HAV.Results:Both method A and B could detect HAV plasmids up to 10 copies/μL. In the detection of HAV vaccine with gradient dilution, the slope, R 2 value and amplification efficiency of method A, B, and C were all within the acceptable range (-3.446~-3.297, 0.991-0.998, -95.07%-101.051%). For 40 specimens from different sources, the positive detection rates of method A, B, and C were 50% (20/40), 47.5% (19/40), 55% (22/40), and the difference was not statistically significant ( χ2=0.467, P=0.792). Methods A and D have no significant difference in the detection sensitivity of gradient dilution vaccines. For the detection of artificially contaminated oysters with low concentration of HAV, the recovery rate of method D was higher than that of method A, but the difference was not statistically significant (F=0.294, P=0.642). Conclusions:There is no significant difference between method A, B, and C, which is more convenient and fast. When detecting low concentrations of HAV in food, Methods D had a slight advantage, but the detection cost is slightly higher. The detection method can be selected according to the actual situation.

Objective:To study the immunotherapeutic effect of chimeric hepatitis B core protein virus-like particles in subcutaneous lung adenocarcinoma mouse model, lays the foundation for the progression of tumor nano-therapeutic technology development.Methods:The plasmid was constructed by inserting a B-cell epitope of the human epidermal growth factor receptor-2 (HER-2) at hepatitis B core protein′s major immunodominant region (MIR). The recombinant virus nanoparticle, denoted as HBc-HER2, was obtained by E. coli expression system, followed by a series of purification steps. The immune response to this recombinant protein nanoparticle was assessed by measuring levels of anti-HER-2 antibody levels and characterizing antibody isotypes in a subcutaneous tumor mice model of lung adenocarcinoma. While tumor therapeutic efficacy was evaluated by measuring tumor size changes with an electronic caliper and MRI photography of subcutaneous tumor in mice.Results:A high-purity HBc-HER2 recombinant protein was obtained and could assemble into nanoparticle. Animal studies had demonstrated the robust immunogenicity of this vaccine in inducing high levels of HER-2 specific antibodies, yielding positive therapeutic outcomes against tumors.Conclusions:The engineered HBc-HER2 demonstrated notable tumor therapy efficacy in a subcutaneous lung adenocarcinoma mouse model, offering a foundation for tumor therapeutic nanotechnology vaccine research.

Objective To compare the performance of three nucleic acid detection methods for hepatitis E virus.Methods The open reading frame (ORF) 2 gene sequence of HEV genotype 4 representative strain was cloned into pUC57 vector.Plasmid DNA was detected by two real-time quantitative method A and B,and the detection limits were compared.Other samples were used for specificity detection.Serum specimens of acute hepatitis E patients were detected by three method,and the results were compared.Results The lowest detection limit of plasmid DNA by A and B method can both reach 35 copies/reaction,with specificity of 100％.The HEV RNA positive rate of serum samples from acute hepatitis E patients by A,B and C method was 47.8％ (43/90),43.3％ (39/90) and 41.1％ (37/90),with the concordance rate of 88.9％ (80/90).There was no statistically significant difference among the three method (x2=0.8414,P=0.6566).Serum specimens with Ct values below 34.6 detected by method A,or below 35.6 detected by method B,the success rate of amplification by method C was 100％.Conclusions Method A has both higher sensitivity and specificity,and method C is a sensitive gene detection method.

Objective: Two kits for detecting anti-HAV antibody produced by Abbott Laboratories are evaluated for their performance in order to use in the anti-HAV antibodies detections. Methods: Serially diluted standard reference serum were detected 4 times with HAVAb2.0 kit and HAV-IgG kit , then fit standard curves and calculated Interclass correlation coefficient (ICC). 120 serum that have different levels of anti-HAV antibodies were chosen to be detected by two kits and calculated sensitivity and specificity, receive operation characteristic (ROC) curve and area under curve (AUC) while the results of HAV-IgG were used as golden standard. Results: R² and ICC for HAV-IgG were 0.9977 and 0.999, respectively, higher than 0.9893 and 0.995(P>0.05) for HAVAb2.0. Sensitivity and specificity for HAVAb2.0 were 93.15% and 100% and AUC was 0.994 when kit HAV-IgG was chosen as golden standard. Conclusion There is little difference in performance between HAV-IgG and HAVAb2.0, both of them can be used in anti-HAV antibodies detection.

High cholesterol is one of the important factors inducing cardiovascular and cerebrovascular diseases. Drug therapy is the main method for reducing cholesterol, but has the disadvantages such as high cost and side effects. Studies have shown that intestinal bacteria play important roles in cholesterol metabolism. However, there are few reports on the screening and functional evaluation of cholesterol-lowering intestinal bacteria. In this study, 36 bile-tolerant bacteria were screened from healthy people stool through culturomics using bovine bile acid or artificial mixed bile acids as substrates. Taking Lactobacillus rhamnosus GG (LGG) as a positive control, three bile acid concentration groups (0 g/L, 0.3 g/L, 3 g/L) were set up to evaluate the cholesterol-lowering ability of bile-tolerant bacteria in vitro. Ten bacteria (including Proteus mirabilis, Providencia stuartii, Proteus vulgaris et al) were identified as the dominant cholesterol-lowering bacteria. Six of the above bacteria, Proteus mirabilis, Providencia stuartii, Proteus vulgaris, Proteus penneri, Wohlfahrtiimonas chitiniclastica, Providencia rettger, were evaluated for their ability to reduce triglycerides in vitro and tolerance to artificial gastric juice. Comparing with strain LGG, the six bacteria showed better triglyceride-lowering ability in vitro. With the decrease of pH value of artificial gastric juice and the increase of treatment time, the survival rate of six bacteria decreased. The above screening experiments and functional evaluation provide a basis for further development of potential cholesterol-lowering bacterial products.
Animals ; Cattle ; Cholesterol ; Gammaproteobacteria ; Humans ; Proteus mirabilis ; Providencia