Objective:To obtain a prevalent respiratory syncytial virus (RSV) clinical isolate in Beijing and analyze the genotype and biological characteristics of the strain.Methods:A nasopharyngeal secretion specimen was collected from a child with RSV infection in Beijing in 2023 and used for viral isolation. Viral nucleic acid was amplified using qRT-PCR. The isolated virus was identified by transmission electron microscopy, indirect immunofluorescence assay, and plaque formation assay. A phylogenetic analysis was conducted based on the whole-genome sequencing results. Virus titers were determined, and replication characteristics were analyzed. The efficacy of the isolated strain for in vitro screening of antiviral drugs was validated. Results:A clinical RSV isolate, named hRSV/C-Tan/BJ 202301, was successfully isolated, which could form syncytia in Hep-2 cells. Spherical, filamentous, and irregular virus particles were observed by electron microscopy. Immunofluorescence detection showed green fluorescence in Hep-2 cells, and plaque assay showed round plaques, which were similar to the Long strain in morphology. Genomic sequence analysis showed that it belonged to ON1 genotype. It exhibited similar cell growth kinetics characteristics with the Long strain and could be used for antiviral drug screening in vitro. Conclusions:In this study, one RSV strain is successfully isolated and identified. The biological characteristics and the phylogenetic relationship of this strain reflect the characteristics of the circulating strains in Beijing, which provides experimental material for RSV vaccine development and antiviral drug screening in China.

Objective:To establish and optimize a novel method, focus forming assay (FFA), for quantitation of influenza A virus (FluA) and compare its application performance with traditional plague forming assay (PFA).Methods:The foci chromogenic effects of three peroxidase substrates in immunostaining were compared. The PFA and FFA methods were used to explore FluA incubation times and plaque morphology on 12-well plates, and to determine optimal incubation times and virus adsorption volumes for different FluA subtypes on 96-well plates. The correlation between FFA and PFA was evaluated, and the optimized FFA was applied to the in vitro antiviral efficacy analysis of Favipiravir and neutralization test against different subtypes of FluA. Results:TRUEBLUE substrate was identified as the optimal substrate for foci visualization. Compared with the PFA, the FFA showed improved sensitivity and reduced detection time in FluA titration, and good correlation was shown between the two methods′ results. By replacing the 96-well plate with the 12-well plate for FFA titration of different subtypes of FluA, the detection time was shortened, and the amount of serum samples used could be further reduced by optimizing the virus adsorption volume. The half-maximal effective concentration of favipiravir against influenza viruses assessed by the FFA and PFA methods showed no significant difference, and was consistent with the results obtained from quantitative PCR. Additionally, the focus reduction neutralization test and hemagglutination inhibition assays demonstrated strong correlation in determining antibody titers against FluA in serum neutralization assays.Conclusions:The improved FFA method developed here provides a more efficient experimental tool for FluA titration, antiviral drug screening and broad-spectrum vaccine evaluation.

Objective:To obtain a prevalent respiratory syncytial virus (RSV) clinical isolate in Beijing and analyze the genotype and biological characteristics of the strain.Methods:A nasopharyngeal secretion specimen was collected from a child with RSV infection in Beijing in 2023 and used for viral isolation. Viral nucleic acid was amplified using qRT-PCR. The isolated virus was identified by transmission electron microscopy, indirect immunofluorescence assay, and plaque formation assay. A phylogenetic analysis was conducted based on the whole-genome sequencing results. Virus titers were determined, and replication characteristics were analyzed. The efficacy of the isolated strain for in vitro screening of antiviral drugs was validated. Results:A clinical RSV isolate, named hRSV/C-Tan/BJ 202301, was successfully isolated, which could form syncytia in Hep-2 cells. Spherical, filamentous, and irregular virus particles were observed by electron microscopy. Immunofluorescence detection showed green fluorescence in Hep-2 cells, and plaque assay showed round plaques, which were similar to the Long strain in morphology. Genomic sequence analysis showed that it belonged to ON1 genotype. It exhibited similar cell growth kinetics characteristics with the Long strain and could be used for antiviral drug screening in vitro. Conclusions:In this study, one RSV strain is successfully isolated and identified. The biological characteristics and the phylogenetic relationship of this strain reflect the characteristics of the circulating strains in Beijing, which provides experimental material for RSV vaccine development and antiviral drug screening in China.

Objective:To establish and optimize a novel method, focus forming assay (FFA), for quantitation of influenza A virus (FluA) and compare its application performance with traditional plague forming assay (PFA).Methods:The foci chromogenic effects of three peroxidase substrates in immunostaining were compared. The PFA and FFA methods were used to explore FluA incubation times and plaque morphology on 12-well plates, and to determine optimal incubation times and virus adsorption volumes for different FluA subtypes on 96-well plates. The correlation between FFA and PFA was evaluated, and the optimized FFA was applied to the in vitro antiviral efficacy analysis of Favipiravir and neutralization test against different subtypes of FluA. Results:TRUEBLUE substrate was identified as the optimal substrate for foci visualization. Compared with the PFA, the FFA showed improved sensitivity and reduced detection time in FluA titration, and good correlation was shown between the two methods′ results. By replacing the 96-well plate with the 12-well plate for FFA titration of different subtypes of FluA, the detection time was shortened, and the amount of serum samples used could be further reduced by optimizing the virus adsorption volume. The half-maximal effective concentration of favipiravir against influenza viruses assessed by the FFA and PFA methods showed no significant difference, and was consistent with the results obtained from quantitative PCR. Additionally, the focus reduction neutralization test and hemagglutination inhibition assays demonstrated strong correlation in determining antibody titers against FluA in serum neutralization assays.Conclusions:The improved FFA method developed here provides a more efficient experimental tool for FluA titration, antiviral drug screening and broad-spectrum vaccine evaluation.

Objective To evaluate the efficacy and safety of domestic human recombinant FSH (rhFSH) in women with anovulation of WHO groupⅡ. Methods A randomized, blind, parallel-controlled, non-inferiority and multicenter study was performed. A total of 534 admitted to 13 hospitals from May 2008 to August 2009. There were 531 women with ovulatory disorder was included in the statistical analysis, were randomly divided into test group (domestic rhFSH, n=352) and control group (imported rhFSH, n=179). Percentage of cycle with mature follicle, ovulation rate, clinical pregnancy rate, multiple pregnancy rate, ovarian hyperstimulation syndrome (OHSS) and adverse events were observed. Results No statistical significant differences (P>0.05) were observed between the two groups in terms of the efficiency on mature follicle [91.8%(323/352) versus 88.8%(159/179)], ovulation rate [91.3%(295/323) verus 90.6%(144/159)], clinical pregnancy rate [19.2%(62/323) verus 18.2%(29/159)], the number of the follicles<14 mm, the level of serum LH and progesterone, the thickness of endometrium on the day of hCG administration. The number of follicle≥18 mm and 14 mm≤follicle<18 mm and the level of serum estradiol on the day of hCG in the test group were significantly higher than those in the control group (P<0.05). The number of days of rhFSH administration in the test group was significantly less than that in the control group [(9.8±2.2) versus (11.4± 0.6) days, P<0.05], the dosage of rhFSH was significantly lower than that in the control group [(879 ± 419) versus (1 043 ± 663) U, P<0.05]. The multiple pregnancy rate in the test group was significantly higher than that in the control group [21% (13/62) versu 10% (3/29), P<0.05]. The incidence of OHSS and adverse events were similar between the two groups (P>0.05), and no other adverse events were observed in test group during treatment. Conclusion Ovarian stimulation with domestic rhFSH is effective, safe and economical in women with anovulation of WHO groupⅡ.

OBJECTIVETo investigate the damage effect of different fractions from Polygonum multiflorum on normal human liver and liver cancer cells, in order to seek for fractions that can obviously kill cancer cells but have less impact on normal liver cells, and make a preliminary study on different mechanism of the two kinds of cells.

METHODP. multiflorum water-eluted fraction (RW), 50% ethanol-eluted fraction (R50) and 95% ethanol-eluted fraction (R95) were successively obtained from 70% ethanol extracts of P. multiflorum, after being eluted by water, 50% ethanol and 95% ethanol and then absorbed by AB-8 macroporous resin. Normal human liver L02 cells and liver cancer HepG2 cells were incubated with cell supernatants from different fractions and cells. MTT method and inverted microscope were adopted to observe the impact of L02 on growth of HepG2 cells, screening fractions with damage effect and detect their doses and time effect. Giemsa stain showed changes in cell nucleus after administration and flow cytometry analysis was used to detect cycle and apoptosis of L02 cells.

RESULTMTT method and inverted microscope showed that R50 had significant growth inhibition effects on L02 and HepG2 cells. According to giemsa stain and flow cytometry analysis, R50 showed different effect on inducing the two cells: there are much more apoptotic HepG2 cells than apoptotic L02 cells in each time phase (the proportion of the apoptosis cells in HepG2 group were 83.62%, 60.52% and 74.49%, and ID2 31.02%, 20.57% and 25.32% after treated with R50 for 24, 48, 72 h. Both cells showed less than 5% of apoptotic cells in the negative control group in each time phase). However, there is no significant impact on cycle of both cells.

CONCLUSIONR50 from P. multiflorum extracts had different damage effects on human liver L02 cells and liver cancer HepG2 cells, which was caused by different degree of induction on apoptosis of the two cells in nature.

Antineoplastic Agents ; adverse effects ; pharmacology ; Apoptosis ; drug effects ; Cell Cycle ; drug effects ; Cell Proliferation ; drug effects ; Dose-Response Relationship, Drug ; Drugs, Chinese Herbal ; adverse effects ; pharmacology ; Hep G2 Cells ; Humans ; Liver ; cytology ; pathology ; Liver Neoplasms ; pathology ; Polygonum ; chemistry

AIM: To investigate the adsorptive and separative properties of 5 kinds of macroporous adsorbing resins to the total saponins and alkaloids, which treated atrophic gastritis with Sanqi Qilian Decoction (Radix et Rhizoma Notoginseng, Radix Astragali, Rhizoma Coptidis.) METHODS: The adsorption capacities, contents and recoveries of the total saponins and alkaloids were selected as the evaluating quotas. The determination of the contents of the total saponins and alkaloids and the investigation into leakage and elution curve were completed with UV-VIS spectrophotometric method. RESULTS: AB-8 resin had the best adsorptive and separative properties to the total saponins and alkaloids in Sanqi Qilian Decoction. The applicable technology was as follows: the concentration of original solution of the extract of Sanqi Qilian Decoction was 40 mg/mL; the largest adsorption capacities on resin to the total saponins and alkaloids were 5.28 mg/mL and 12.38 mg/mL respectively; the eluant was 50% ethanol with 8 times of resin volume, and the elution velocity was 2 mL/min. AB-8 resin could be used for 4 times repeatedly after being reproducted by 95% ethanol and 1 mol/L NaOH. CONCLUSION: Under the process condition which had been selected above, AB-8 resin can be used successfully to adsorb and separate with over 20% of the content of the total saponins Sanqi Qilian Decoction, and 30% of the content of the total alkaloids in the 50% ethanol eluate, and with over 75% of total saponins recovery and 65% of total alkaloids recovery respectively.