[HCV antigen detection method and clinical application].

Hepatitis C is distributed worldwide and possesses a hidden characteristic. The traditional methods of screening and diagnosis of hepatitis C infection commonly used in clinics are based on anti-HCV antibody and HCV RNA detection. Advances in HCV antigen detection technologies can apparently reduce the window period for anti-HCV antibodies, providing new clinical evidence for the early detection, diagnosis, and treatment of HCV infection. This article is a current review of HCV antigen detection methodologies, clinical applications, and detection strategies.

[Inhibitory effect of small-molecule compound AM679 targeting elongation-factor binding protein 2 on hepatitis B virus in vitro].

Objective: To explore the antiviral activity of the small-molecule compound AM679 in hepatitis B virus (HBV) replication and infection cell models. Methods: The positive regulatory effect of AM679 on EFTUD2 expression was validated by qPCR and Western blotting. HepAD38 and HepG2-NTCP cells were treated with AM679 (0.5, 1, and 2 nmol/L). Negative control, positive control, and AM679 combined with the entecavir group were set up. HBV DNA intra-and extracellularly, as well as the expression levels of intracellular HBV total RNAs and 3.5kb-RNA changes, were detected with qPCR. Hepatitis B surface antigen (HBsAg) and hepatitis B e antigen (HBeAg) levels were measured in the cell supernatant by an enzyme-linked immunosorbent assay (ELISA). The t-test method was used for the statistical analysis of the mean difference between groups. Results: EFTUD2 mRNA and protein expression levels were significantly increased in HepAD38 and HepG2-NTCP cells following AM679 treatment, with a statistically significant difference (P < 0.001). Intra-and extracellular indicators such as HBV DNA, HBV RNAs, HBV 3.5kb-RNA, HBsAg, and HBeAg were decreased to varying degrees in both cell models, and the decrease in these indicators was more pronounced with the increase in AM679 concentration and prolonged treatment duration, while the combined use of AM679 and entecavir had a more significant antiviral effect. The HBV DNA inhibition rates in the supernatant of HepAD38 cells with the use of 2 nmol/L AM679 were 21% and 48% on days three and nine, respectively. The AM679 combined with the ETV treatment group had the most significant inhibitory effect (62%), with a P < 0.01. More active HBV replication was observed after silencing EFTUD2, while the antiviral activity of AM679 was significantly weakened. Conclusion: AM679 exerts anti-HBV activity in vitro by targeting the regulation of EFTUD2 expression.

[Efficacy of different doses of magnesium isoglycyrrhizinate in the treatment of chronic liver disease with elevated ALT: a meta-analysis].

Objective: To investigate the efficacy and safety profile of different doses of magnesium isoglycyrrhizinate in the treatment of chronic liver disease with elevated alanine aminotransferase (ALT). Methods: Computer retrieval of literature was conducted in the CNKI, Wanfang, and PubMed databases from the establishment of the databases until February 2023. The Cochrane risk of bias assessment tool was used to evaluate the quality of the included literature after screening the literature and extracting the data. RevMan 5.4 and Stata 15.0 software were used to analyze the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBil), total effective rate, and incidence of adverse events. Results: Finally, 10 articles were selected, including a total of 1 522 cases. All the included studies were of good quality and at low risk of bias. Meta-analysis results showed that compared with 100 mg/d magnesium isoglycyrrhizinate injection, 200 mg/d magnesium isoglycyrrhizinate injection had significantly reduced patients' ALT [MD = -30.73, 95% confidence interval (CI): -52.52 ~ -8.94, Z = 2.76, P = 0.006; I (2) = 98%, P < 0.001], AST (MD = -34.30, 95% CI: -57.78 ~ -10.82, Z = 2.86, P = 0.004; I (2) = 99%, P < 0.001) and TBil (MD = -15.37, 95% CI: -27.66 ~ -3.09), Z = 2.45, P = 0.01; I (2) = 98%, P < 0.001) levels. The total effective rate reported in seven articles showed no heterogeneity among the studies (I (2) = 0.0%, P = 0.98). The total effective rate was higher in 200 mg/d magnesium isoglycyrrhizinate injection than that of 100 mg/d magnesium isoglycyrrhizinate injection (OR = 3.49, 95% CI: 2.05 ~ 5.95, Z = 4.59, P < 0.001), and there was no statistically significant difference in adverse reactions. Conclusion: 200 mg/d magnesium isoglycyrrhizinate injection can more rapidly and effectively improve the levels of ALT, AST, and TBil in patients with chronic liver disease, with an increased total effective rate and a good safety profile.

[Validation and modification of AJCC 8th edition staging system for hepatocellular carcinoma--analysis based on SEER database].

Objective: To assess the accuracy of the American Joint Committee on Cancer (AJCC) 8th edition staging system for hepatocellular carcinoma (HCC) and to make an appropriate modification. Methods: Data of patients diagnosed with HCC who underwent surgery were extracted from 2004 to 2015 within the SEER database. Overall survival (OS) and disease-specific survival (DSS) of patients were analyzed. Results: A total of 7 911 patients were included and there were 2 117 females and 5 794 males. The male-to-female ratio was 1.00: 0.36. There were 4 050 patients older than 60 years old. Tumor size ranged from 24 to 65 mm. Tumors with single lobes (80.8%) or single lesions (62.8%) were more common. There were 230 cases and 2 052 cases received radiotherapy and chemotherapy, accounting for 2.9% and 25.9%, respectively. The median follow-up was 42 months. Analysis of the 8th edition of AJCC staging system showed that the survival curves of ⅣA stage and ⅢA stage intersected in both OS and DSS, and the differences were not statistically significant between them (both P>0.05). Analysis of patients in subgroup of ⅣA stage showed that there was no statistically significant difference in the four groups of T1N1M0/T2N0M0, T2N1M0/T3N0M0, T3N1M0/T4N0-1M0 and T3N1M0/T1-4N0-1M1 (all P>0.05). Therefore, the modified 8th edition of the AJCC staging system was proposed after retaining the definition of T/N/M in the old edition: ⅠA and ⅠB stages were retained; ⅣA stage was split: T1N1M0 was included in Ⅱ stage, T2N1M0 in Ⅲ stage, and Ⅳ stage included T3N1M0, T4N0-1M0 and T1-4N0-1M1. Cox proportional risk regression analysis of the modified 8th edition of the AJCC staging showed that significant differences were observed among the four groups, with ⅠB/ⅠA (HR=1.462, 95%CI:1.294-1.651), Ⅱ/ⅠB (HR=1.091, 95%CI:1.003-1.186), Ⅲ/Ⅱ (HR=2.034, 95%CI: 1.793-2.307) and Ⅲ/Ⅳ (HR=1.374, 95%CI: 1.192-1.583) for OS, respectively. The similar findings were seen in DSS, with ⅠB/ⅠA (HR=2.007, 95%CI:1.671-2.411), Ⅱ/ⅠB (HR=1.140, 95%CI:1.023-1.271), Ⅲ/Ⅱ (HR=2.344, 95%CI: 2.018-2.724) and Ⅲ/Ⅳ (HR=1.391, 95%CI:1.180-1.639), respectively. Conclusion: The modified AJCC 8th edition staging system could predict the survival outcome of HCC more accurately.

A novel miRNA, miR-13664, targets CpCYP314A1 to regulate deltamethrin resistance in Culex pipiens pallens.

Extensive insecticide use has led to the resistance of mosquitoes to these insecticides, posing a major barrier to mosquito control. Previous Solexa high-throughput sequencing of Culex pipiens pallens in the laboratory has revealed that the abundance of a novel microRNA (miRNA), miR-13664, was higher in a deltamethrin-sensitive (DS) strain than a deltamethrin-resistant (DR) strain. Real-time quantitative PCR revealed that the miR-13664 transcript level was lower in the DR strain than in the DS strain. MiR-13664 oversupply in the DR strain increased the susceptibility of these mosquitoes to deltamethrin, whereas inhibition of miR-13664 made the DS strain more resistant to deltamethrin. Results of bioinformatic analysis, quantitative reverse-transcriptase polymerase chain reaction, luciferase assay and miR mimic/inhibitor microinjection revealed CpCYP314A1 to be a target of miR-13664. In addition, downregulation of CpCYP314A1 expression in the DR strain reduced the resistance of mosquitoes to deltamethrin. Taken together, our results indicate that miR-13664 could regulate deltamethrin resistance by interacting with CpCYP314A1, providing new insights into mosquito resistance mechanisms.

Impact of treatments on fecal microbiota and fecal metabolome in symptomatic uncomplicated diverticular disease of the colon: a pilot study.

Symptomatic uncomplicated diverticular disease (SUDD) affects 50% of people having diverticulosis. We performed a pilot study assessing the effect of current treatments on fecal microbiota and metabolome in SUDD. Thirteen consecutive females with SUDD were treated with a 2-week therapeutic trial of 30 g/day fiber supplementation (3 patients), 1.6 g/day of mesalazine (3 patients), 900 billion/day of probiotic mixture VivoMixx® (3 patients), or 800 mg/day of rifaximin (4 patients). Stool samples were collected at entry (T0), at the end of the 2-week therapeutic course (T1), and 30 (T2) and 60 days (T3) after the end of the therapeutic course. Real-time PCR quantified targeted microorganisms. Fecal metabolome patterns were studied by high-resolution proton NMR spectroscopy. At cumulative analysis, symptoms significantly decreased at each time point during follow-up (p less than 0.0001), and only left-lower quadrant pain increased again at T3. The overall bacterial quantity was not altered by the treatments. The amount of Akkermansia muciniphila species was significantly reduced at T1 (p=0.017) and at T2 (p=0.026), while at T3 the reduction was not significant in comparison to enrollment (p=0.090). Fecal molecular profile showed significant changes at T1 and T2, while at T3 it became similar to that of T0. Differences were found for 18 of the quantified molecules (tryptophan, phenylalanine, tyrosine, 4-hydroxyphenylacetate, urocanate, X-6.363, X-5.779, uridylate, galactose, X-4.197, threonine, sarcosine, methionine, 2-oxoisocaproate, 5-aminolevulinate, alanine, leucine, valerate). Metabolome and microbiota changed in patients with SUDD under treatment, confirming a possible role of dysbiosis/dysmetabolome in the pathology.

Investigation of serum vitamin D levels in Chinese infertile men.

Recently, the question of whether vitamin D exerts an effect on the pathogenic process of infertility has become the centre of attention. There are some controversial conclusions on this issue. Based on previous studies, we sought to explore the difference of serum 25-hydroxyvitamin D3 , 1,25-dihydroxyvitamin D3 levels between infertile patients and fertile men, and to find the influence on semen quality. The analysis of serum 25-hydroxyvitamin D3 level showed no significant difference between infertile patients and fertile men. However, the levels of serum 1,25-dihydroxyvitamin D3 in oligospermia (P < 0.05), asthenospermia (P < 0.01), oligoasthenospermia (P < 0.05) and azoospermia (P < 0.01) patients were significantly lower than those in fertile men. Moreover, serum 1,25-dihydroxyvitamin D3 level was positively correlated with progressive motility and total sperm number in infertile patients. In addition, a positive correlation between serum prolactin and 1,25-dihydroxyvitamin D3 was observed in fertile men. Our results indicated that lower vitamin D could be a risk factor for poor semen quality in infertile men. The 1,25-dihydroxyvitamin D3 , as the biologically active form of vitamin D, may be more significant.

Identification and validation of a new grain weight QTL in rice.

The genetic control of grain weight (GW) remains poorly understood. Quantitative trait loci (QTLs) determining the GW of rice were identified using a natural GW mutant, sgw. Using a segregating population derived from sgw (low GW) and cultivar 9311 ('9311'; indica, high GW), the chromosome segment associated with GW was detected on the short arm of chromosome 7. To validate and further refine the locus, QTL analysis based on F2 and F3 populations was conducted, and a single major QTL (designated as qsgw7) affecting the 1000-grain weight of paddy rice was identified on the short arm region of rice chromosome 7 between simple sequence repeat (SSR) markers RM21997 and RM22015, where 4 bacterial artificial chromosome clones, OJ1339_F05, P0506F02, P0011H09, and P0519E12, were present. Analysis of the near isogenic line for qsgw7 (NILqsgw7) showed that the grain length, width, and volume of paddy rice in NILqsgw7 were significantly lower than those in '9311' and that the 1000-grain weight, grain length, width, volume, and chalkiness of brown rice in NILqsgw7 were significantly lower than those in '9311'. These results suggested that the qsgw7 gene, which was identified in this study, may be a new GW-related QTL that could affect GW and grain shape, especially grain plumpness.

The association of serum Kallikrein-8 with cognitive function in vascular dementia.

OBJECTIVE: Kallikrein-8 (KLK8) is a secreted serine protease related to learning and memory. Evidence has confirmed the important role of KLK8 in neuroplasticity. However, the role of KLK8 in vascular dementia (VaD) is unclear. PATIENTS AND METHODS: The study recruited 88 VaD patients and 72 normal controls. All subjects were tested for cognitive function by Mini-Mental State Examination (MMSE) upon admission, and their demographic and biochemical data were collected. A sandwich Enzyme-Linked Immunosorbent Assay (ELISA) test was used to detect serum KLK8 levels. The demographic and biochemical data of the two groups of subjects were compared. Spearman's correlation and multivariate regression analysis were used to determine whether serum KLK8 in VaD patients is a risk factor for cognitive function. RESULTS: A total of 88 VaD patients and 72 controls with normal cognitive function were recruited and divided into VaD group and control group. Except for TT3 (p=0.002), there was no statistically significant difference in other demographic and biochemical data between the two groups (p>0.05). The results of ELISA indicated that the serum KLK8 in VaD patients was significantly higher than that of the control population (p<0.001). Spearman correlation analysis indicated that the serum KLK8 in VaD was significantly inversely correlated with the MMSE score. The results of Spearman's correlation analysis showed that the serum KLK8 level of VaD was significantly inversely correlated with the MMSE (r=-0.305, p=0.017). After correcting for interference factors, the correlation between the two is still significant (ß=0.398, p=0.024). CONCLUSIONS: Serum KLK8 may be an independent risk factor affecting the cognitive function of VaD, which is worthy of further research.

Stimulatory effect of LPS and feedback effect of PGE2 on IL-27 production.

Interleukin (IL)-27 is a new member of the IL-6/IL-12 family, composed of two subunits, the Epstein-Barr virus-induced gene 3 (EBI3) and p28 chains (p28), and produced by activated monocytes and dendritic cells. IL-27 plays an important role in the regulation of differentiation of naive T helper cells and has diverse effects on innate immune cells. However, the pro-inflammatory mechanisms of IL-27 are still not well known. In this study, we investigated the effect of lipopolysaccharide (LPS) on the production of IL-27. We found that LPS-stimulated IL-27 production was in a dose-dependent and time-dependent manner in THP-1 cells. We have also shown that IL-27 induced PGE2 production and COX-2 gene expression at the level of mRNA as well as protein. Moreover, we found feed back effect of PGE2 on the production of IL-27 in THP-1 cells. The results suggest that PGE2 significantly inhibits LPS-induced IL-27 production, without affecting basal IL-27 expression. Further experiment suggests that PGE2 and LPS regulate IL-27 through NF-κB pathway. Our findings may have wide implication for IL-27 in inflammatory diseases.

The dehydration effect on mechanical properties of tooth enamel.

Exploring the subtle mechanical property changes of tooth enamel in different conditions is important for dental research. However, some experimental results can be deceptive and may lead to misunderstanding. In particular, we show the dehydration associated with increased mechanical properties of tooth enamel as monitored by Nanomechanical System Testing (NST) can be misleading. The results indicate that the friction coefficient decreased with an increase of hardness of enamel upon dehydration, which appears to imply that dehydrated enamel has better mechanical properties than hydrated enamel. However, more critical scrutiny of the actual situation, suggests dehydrated teeth enamel are more prone to damage and greater wear. To appreciate the basis for the contrast between the experimental results and reality of natural hydrated enamel, which has better resistance to wear, and is critical for an understanding of the aetiology of enamel resistance to fracture.

Downregulation of COPB2 by RNAi inhibits growth of human cholangiocellular carcinoma cells.

OBJECTIVE: The present study aimed to explore the contribution of COPB2 (coatomer subunit beta) towards the tumorigenesis of cholangiocellular carcinomas and to elucidate the underlying mechanism(s). MATERIALS AND METHODS: Expression of COPB2 mRNA by RBE and QBC939 cholangiocellular carcinoma cell lines was determined by qRT-PCR. We, then, silenced COPB2 expression in RBE cells by infection with a COPB2-siRNA lentivirus and measured the proliferation, cell-cycle distribution, and apoptosis of transduced cells. RESULTS: COPB2 was highly expressed in RBE and QBC939 cholangiocellular carcinoma cell lines. Infection with COPB2-siRNA lentivirus in RBE cells significantly decreased COPB2 expression. More so, silencing of COPB2 by COPB2-siRNA significantly suppressed the proliferation and promoted the apoptosis of RBE cells by arresting transduced cells in the G1 phase. CONCLUSIONS: Our results demonstrate that the COPB2 gene is highly expressed in cholangiocellular carcinoma cell lines, wherein knockdown inhibited the proliferation and promoted the arrest of cell-cycle progression and the apoptosis of cholangiocellular carcinomas. COPB2 may constitute an attractive target for therapeutic strategies against cholangiocellular cancers.

Effect of supplemental dietary leucine and immune system stimulation on whole-body nitrogen utilization in starter pigs.

The increase in circulating pro-inflammatory cytokines following an immune challenge (e.g., with bacterial lipopolysaccharide [LPS]) causes a disruption in normal AA metabolism and increases visceral protein synthesis at the expense of muscle protein synthesis. The objective of this study was to determine the effect of supplemental dietary Leu on the dynamics of whole body nitrogen (N) retention in starter pigs before and after immune system stimulation (ISS) induced by LPS. A total of 28 starter pigs (14.46 ± 0.73 kg BW) were assigned to isoenergetic and isonitrogenous diets formulated to supply essential AA 10% above estimated requirements for maximum whole-body protein deposition (PD) and to contain increasing amounts of Leu: CON (1.36% SID Leu); LEU-M (2.04% SID Leu); and LEU-H (2.72% SID Leu). Pigs were housed in metabolic crates, scale-fed every 4 h based on BW, and adjusted to dietary treatments for 5 d. The 108-h N-balance experiment was divided into two periods: prechallenge (before LPS challenge; six 12-h collections) and challenge (after LPS challenge; three 12-h collections) periods. In both periods, blood was collected to determine plasma AA and urea N concentrations. At the start of the challenge period, one-half of the pigs fed CON and all pigs fed LEU-M and LEU-H were challenged with LPS (ISS+; 30 µg/kg injected intramuscularly); the remaining pigs fed CON were injected with saline (ISS-). Whole-body N retention was determined during subsequent 12-h collections. Plasma free Leu concentration increased linearly with increasing Leu content in the diet before LPS was administered (CON, 124 µmol/L; LEU-M, 185 µmol/L; LEU-H, 227 µmol/L; < 0.01). During the prechallenge period, N retention was lower in pigs fed LEU-M ( < 0.01) and there was no difference between pigs fed CON and LEU-H (7.91, 7.18, and 7.71 g/12 h for CON, LEU-M, and LEU-H, respectively). During the challenge period, N retention in pigs fed CON was higher in ISS- than ISS+ (5.37 vs. 3.83 g/12 h; < 0.01) but was not affected by diet in ISS+ pigs (3.83, 3.21, and 3.45 g/12 h for CON, LEU-M, and LEU-H, respectively; > 0.10). In healthy pigs, feeding a high excess of dietary Leu induced an anabolic response to compensate for reduced N retention that occurred in pigs fed an intermediate excess of dietary Leu. There was no effect of supplemental Leu on N retention in pigs after an LPS challenge.

Identification of protease m1 zinc metalloprotease conferring resistance to deltamethrin by characterization of an AFLP marker in Culex pipiens pallens.

BACKGROUND: Continuous and excessive application of deltamethrin (DM) has resulted in the rapid development of insecticide resistance in Culex pipiens pallens. The quantitative trait loci (QTL) responsible for resistance to DM had previously been detected in Cx. pipiens pallens. But locating the QTLs on the chromosomes remained difficult. An available approach is to first characterize DNA molecular markers linked with the phenotype, and then identify candidate genes. METHODS: In this study, the amplified fragment length polymorphism (AFLP) marker L3A8.177 associated with the QTL, was characterized. We searched for potential candidate genes in the flank region of L3A8.177 in the genome sequence of the closely related Cx. pipiens quinquefasciatus and conducted mRNA expression analysis of the candidate gene via quantitative real-time PCR. Then the relationship between DM resistance and the candidate gene was identified using RNAi and American CDC Bottle Bioassay in vivo. We also cloned the ORF sequences of the candidate gene from both susceptible and resistant mosquitoes. RESULTS: The genes CYP6CP1 and protease m1 zinc metalloprotease were in the flank region of L3A8.177 and had significantly different expression levels between susceptible and resistant strains. Protease m1 zinc metalloprotease was significantly up-regulated in the susceptible strains compared with the resistant and remained over-expressed in the susceptible field-collected strains. For deduced amino acid sequences of protease m1 zinc metalloprotease, there was no difference between susceptible and resistant mosquitoes. Knockdown of protease m1 zinc metalloprotease not only decreased the sensitivity of mosquitoes to DM in the susceptible strain but also increased the expression of CYP6CP1, suggesting the role of protease m1 zinc metalloprotease in resistance may be involved in the regulation of the P450 gene expression. CONCLUSION: Our study represents an example of candidate genes derived from the AFLP marker associated with the QTL and provides the first evidence that protease m1 zinc metalloprotease may play a role in the regulation of DM resistance in Cx. pipiens pallens.

Exploration of the mechanisms of biofilm formation by Enterococcus faecalis in glucose starvation environments.

BACKGROUND: Enterococcus faecalis is the most common single species present in teeth after failed root canal therapy. This is mainly due to its ability to maintain viability for a long time in filled root canals where nutrients are normally sparse. The aim of this study was to explore the mechanism of E. faecalis survival and biofilm formation in glucose-starved environments. METHODS: Enterococcus faecalis ATCC 33186 was inoculated in energy starvation media for biofilm formation. Confocal laser scanning microscopy and fluorescent DNA-binding agents were employed to assess biofilm-forming ability. The physiochemical properties of the biofilm cell wall were investigated by measuring the hydrophobicity, extracellular polysaccharide and ATPase activity. The expression of stress and virulence genes was quantified by real-time quantitative polymerase chain reaction. RESULTS: The ability for biofilm formation decreased with a decreasing concentration of glucose. The cell surface hydrophobicity increased dramatically with decreasing glucose concentration. Water-soluble exopolysaccharide (WSE) synthesis decreased in glucose starvation media, whereas water-insoluble exopolysaccharide (WIE) synthesis increased. A marked decrease in ATPase activity was observed only in a no glucose medium. In addition, transcription of ace, fsrB and gelE genes increased under glucose starvation stress while atpE, salB and esp genes were down-regulated. CONCLUSIONS: Enterococcus faecalis survival and biofilm formation under glucose starvation stress may be attributed to an increase in cell-surface hydrophobicity and additionally to the up-regulation of some genes involved in stress response and biofilm formation. These characteristics may explain why E. faecalis can maintain viability for a long time in an energy-starved environment and why it is frequently isolated from persistently infected root canals.

Dysfunction of peripheral blood dendritic cells from patients with chronic hepatitis B virus infection.

AIM: To identify the property of dendritic cells (DCs) of peripheral blood monocytes (PBMC) in patients with chronic HBV infection. METHODS: Twenty patients with persistent HBV infection were included in this study, 10 healthy subjects being used as a control group. The peripheral blood mononuclear cells (PBMC) of T cell-depleted populations were incubated and induced into mature dendritic cells in the RPMI-1640 medium in the presence of cytokines GM-CSF, IL-4, FLt-3,TNF-alpha and 100mL.L(-1 )of fetal calf serum for a total of 10-12 days. The expressions of surface markers on DCs were evaluated using flow cytometric analysis. ELISA method was used to determine the cytokine levels of interleukin-12 (IL-12) and IL-10 in the supernatant produced by DCs. For detection of the stimulatory capacity of DCs to T cell proliferation, mytomycin C-treated DC were incubated with allogenic T cells. RESULTS: A typical morphology of mature DCs from healthy subjects and HBV-infected patients was induced in in vitro incubation, but the proliferation ability and cellular number of DCs from HBV-infected patients significantly decreased compared with healthy individuals. In particular, the expression levels of HLA-DR, CD80 (B7-1) and CD86 (B7-2) on DC surface from patients were also lower than that from healthy individuals (0.46 vs 0.92 for HLA-DR, 0.44 vs 0.88 for CD80 and 0.44 vs 0.84 for CD86,P<0.05). The stimulatory capacity and production of IL-12 of DCs from patients in allogenic mixed lymphocyte reaction (AMLR) significantly decreased, but the production level of nitric oxide (NO) by DCs simultaneously increased compared with healthy subjects (86 +/- 15 vs 170 +/- 22 micromol.L(-1), P <0.05). CONCLUSION: The patients with chronic HBV infection have the defective function and immature phenotype of dendritic cells, which may be associated with the inability of efficient presentation of HBV antigens to host immune system for the clearance of HBV.

[Studies of the genetic polymorphism of Schistosoma japonicum (Chinese mainland strains)].

In order to analyze the interspecies diversity and the extent of diversity among Schistosoma japonicum Chinese mainland strains, the genetic variation on gene level among 6 isolates collected from Jiangxi, Hunan, Hubei, Anhui, Sichuan, Yunnan and a cultured isolate from a laboratory were studied using molecular biological technique. There were only two different bases at position 112 and 143 in 536 bp sequence of 28S rDNA-D2 domain between Anhui and Yunnan isolates, the homology was 99.6%. The result could be explained the reason of why the migration rates of single chain 28S rDNA-D2 domain among the above 7 isolates were the same completely in PCR-SSCP. However, comparing with the sequences of the Philippine isolate of S. japonicum, S. mansoni and S. aematobium, there were 6, 94 and 93 different bases and the homologies were 98.9, 82.5 and 82.7 per cent separately. With 8 restriction endonucleases to analyze the ITS of rDNA obtained by PCR from the 7 isolates, the results showed that only 3 minor bands were different, e.g. 5.3% of total 58 fragments. It was suggested that the ITS of rDNA among 7 isolates were highly conserved. Using randomly amplified polymorphic DNA (RAPD) to analyze the genetic diversity of the genomes of the 7 isolates, the average genetic distance (D) calculated from total 284 amplified fragments was 0.22. The maximum D was 0.30 and existed between Anhui and Yunnan isolates. The minimum D was 0.13 and existed between Sichuan and Yunnan isolates. The clustering analysis of genetic distances showed that the 7 isolates could be gathered in one group. From above three results, it could be considered that the genetic diversity on gene level among S. japonicum Chinese mainland strains was very low.

[The significance and state of pre-S2 and antibodies to pre-S2 in 30 cases of acute viral hepatitis type B].

Determination of time sequence of pre-S2 and its antibody response during the symptomatic phase of acute viral hepatitis type B, as well as their relationship to the HBV-markers, was carried out in 30 subjects after the onset of liver damage by means of monoclone antibody-captured enzyme immunoassay were analysed. The results showed that anti-pre-S2 were positive in 80.3% of patients recovering from acute viral hepatitis type B, being higher than the percentage during maximal liver damage (P less than 0.001). Such antibodies were absent in cases showing chronic evolution and were found in less than 8% of chronic hepatitis B cases, with no relation to liver damage. Anti-pre-S2 were detected after the immune clearance of HBsAg and HBV-DNA, and thereafter the anti-HBs were present in 80% of patients after recovery (P less than 0.001). Our observations significantly suggest that anti-pre-S2 may be valuable as a marker of the favourable prognosis of acute viral hepatitis type B and of HBV clearance. They did not play any role in the pathogenesis of HBV-related liver damage. The continuous presence of pre-S2 with the absence of anti-pre-S2, on the contrary, is considered as a characteristic sign and a new information of chronic viral hepatitis type B.

Pharmacological study of an irreversible partial agonist of opiate receptors, A-alpha-CAO.

A-alpha-CAO induces weak analgesia with very short duration in mice and is able to antagonize the analgesic effect of morphine (Mor) up to 3-4 days after a single injection. No tendency of dependence has been observed. It acts as a partial agonist on MVD with Ke value of 9 X 10(-9) mol/L. Its antagonist effect remains after several washes and its agonist effect cannot be reversed by naloxone (Nx), provided the incubation time or the concentration of the agent is sufficient. On isolated GPI, A-alpha-CAO is a pure agonist with IC50 of 5.7 X 10(-10) mol/L; this agonist effect cannot be removed by washing but can be reversed by Nx. On RVD and RbVD, it has antagonist effect against beta-endorphine (beta-end) and U50488H, which cannot be washed out easily, and the pA2 are 7.5 and 7.6 respectively. A-alpha-CAO also inhibits the specific binding of 3H-etorphine (3H-Etor) to the P2 fraction of the mouse brain membrane with an IC50 of 3.2 X 10(-9) mol/L. The inhibition on the high affinity binding sites of 3H-Etor remains 95% even after 6 washes.

[Comparative studies on several biochemical indices of Anopheles anthropophagus and Anopheles sinensis].

Proteins, sugars and esterase isoenzymes of An. anthropophagus and An. sinensis were compared by IEF and two dimensional gel electrophoresis. The results show that there are some differences in the electrophoretic patterns between An. anthropophagus and An. sinensis. The glycoprotein, lipid protein, glycolipidprotein, protein, polysaccharide and esterase isoenzymes showed 10, 0, 6, 14, 2 and 13 bands in An. anthropophagus; 10, 1, 5, 16, 3 and 15 in An. sinensis. There exist 234 and 240 polypeptide spots in An. anthropophagus and in An. sinensis, respectively, altogether 27.8% of polypeptide spots being different.