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1.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-479840

RESUMO

Genetic variation of SARS-CoV-2 has resulted in the emergence and rapid spread of multiple variants throughout the pandemic, of which Omicron is currently the predominant variant circulating worldwide. SARS-CoV-2 variants of concern or interest (VOC/VOI) have evidence of increased viral transmission, disease severity, or decreased effectiveness of vaccines and neutralizing antibodies. Remdesivir (RDV, VEKLURY(R)) is a nucleoside analog prodrug and the first FDA-approved antiviral treatment of COVID-19. Here we present a comprehensive antiviral activity assessment of RDV and its parent nucleoside, GS-441524, against 10 current and former SARS-CoV-2 VOC/VOI clinical isolates by nucleoprotein ELISA and plaque reduction assay. Delta and Omicron variants remained susceptible to RDV and GS-441524, with EC50 values 0.31 to 0.62-fold of those observed against the ancestral WA1 isolate. All other tested variants exhibited EC50 values ranging from 0.15 to 2.3-fold of the observed EC50 values against WA1. Analysis of nearly 6 million publicly available variant isolate sequences confirmed that Nsp12, the RNA-dependent RNA polymerase (RdRp) target of RDV and GS-441524, is highly conserved across variants with only 2 prevalent changes (P323L and G671S). Using recombinant viruses, both RDV and GS-441524 retained potency against all viruses containing frequent variant substitutions or their combination. Taken together, these results highlight the conserved nature of SARS-CoV-2 Nsp12 and provide evidence of sustained SARS-CoV-2 antiviral activity of RDV and GS-441524 across the tested variants. The observed pan-variant activity of RDV supports its continued use for the treatment of COVID-19 regardless of the SARS-CoV-2 variant.

2.
Preprint em Inglês | bioRxiv | ID: ppbiorxiv-423600

RESUMO

Remdesivir (RDV) exhibits potent antiviral activity against SARS-CoV-2 and is currently the only drug approved for the treatment of COVID-19. However, little is currently known about the potential for pre-existing resistance to RDV and the possibility of SARS-CoV-2 genetic diversification that might impact RDV efficacy as the virus continue to spread globally. In this study, >90,000 SARS-CoV-2 sequences from globally circulating clinical isolates, including sequences from recently emerged United Kingdom and South Africa variants, and >300 from mink isolates were analyzed for genetic diversity in the RNA replication complex (nsp7, nsp8, nsp10, nsp12, nsp13, and nsp14) with a focus on the RNA-dependent RNA polymerase (nsp12), the molecular target of RDV. Overall, low genetic variation was observed with only 12 amino acid substitutions present in the entire RNA replication complex in [≥]0.5% of analyzed sequences with the highest overall frequency (82.2%) observed for nsp12 P323L that consistently increased over time. Low sequence variation in the RNA replication complex was also observed among the mink isolates. Importantly, the coronavirus Nsp12 mutations previously selected in vitro in the presence of RDV were identified in only 2 isolates (0.002%) within all the analyzed sequences. In addition, among the sequence variants observed in [≥]0.5% clinical isolates, including P323L, none were located near the established polymerase active site or sites critical for the RDV mechanism of inhibition. In summary, the low diversity and high genetic stability of the RNA replication complex observed over time and in the recently emerged SARS-CoV-2 variants suggests a minimal global risk of pre-existing SARS-CoV-2 resistance to RDV.

3.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-693437

RESUMO

Cell gap junction is a special protein channel.Gap junction-mediated exchange of information between cells is crucial for cell growth,differentiation and tissue homeostasis.Connexin 43 (Cx43) is one of the members of the gap junction protein family.In recent years,researches show that abnormal Cx43 gene expression leads to the cell gap junctional communication dysfunction,which is closely related to the occurrence,metastasis and prognosis of a variety of tumors.Cx43 is expected to become a new target for clinical diagnosis and treatment of tumors.

4.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-692831

RESUMO

Objective Non-muscle myosin heavy chain ⅡA (NMHC ⅡA ) plays a significant role in tumor progression and metastasis .Our prior study showed that the expression of NMHC ⅡA was much higher in human bladder cancer sample than that in adjacent tissue .The increased level of NM HC ⅡA expression was correlated with worse prognosis .However ,the role of NMHC ⅡA is unknown in the invasion and metastasis of bladder cancer .Methods RT-PCR and western blotting were used to examine NMHC ⅡA expression lev-els in normal bladder epithelial cells and bladder cancer cell lines .T he migration and invasion ability of cells was tested by wound healing assay and Transwell invasion assay ,respectively .Results Our study showed that knockdown of NMHC ⅡA inhibited migration and invasion in bladder cancer cell line .Conclusion The study indicated that NM HC ⅡA expression increased the invasion and metastasis ability of bladder cancer cell line in vitro .

5.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-667182

RESUMO

Objective To analyze the genotype distribution characteristics in the patients with α-thalassemia and the relationship between hematological phenotype and genotype .Methods 209 cases of α-thalassemia in our hospital from August to October 2016 were selected and divided into the silence type group (58 cases) ,standard type group(138 cases) ,intermediate type group(4 cases) and non-deletion type group(9 cases) .Contemporaneous 25 subjects undergoing healthy physical examination were selected as the normal control group .The automatic capillary electrophoreses was adopted to detect HbA 2 .The hematological indicators of MCV , MCH and MCHC were detected by using the automatic blood cells analyzer .Results Among 209 cases ofα-thalassemia ,8 mutation genotypes were detected ,in which - - SEA/αα deletion type accounted for 66 .03% ,- α3 .7/αα deletion type accounted for 22 .97% .The levels of MCV ,MCH and MCHC in the silence type group ,intermediate type group ,standard type group and non-de-letion type group was significantly lower than that in the normal control group ,the difference was statistically significant ( P<0 .05) ,the HBA2 level in the intermediate type group was lower than that in the normal control group ,the difference was statisti-cally significant (P<0 .05) ,but the HbA2 level had no statisticval difference between the silence type group ,standard type group and non-deletion type group with the normal control group(P>0 .05) .Conclusion The gene mutation in the patients with α-thalas-semia in Luohu District of Shenzhenis City is dominated by the deletion type of - -SEA/αα.The hematological indicators such as MCV ,MCH and MCHC can serve as the combined screening indexes of α-thalassemia ,but for the patients with -α3 .7/ααgenotypeα-thalassemia ,there is the possibility of missed diagnosis .

6.
Chinese Herbal Medicines ; (4): 58-62, 2012.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-499829

RESUMO

ObjectiveTo evaluate the gastroprotective activity of ascaridole.MethodsThe gastroprotective effect of ascaridole was evaluated on ulcer healing in rats with acetic acid-induced chronic gastric ulcer,pylorus ligation- and Aspirininduced gastric ulcer.Ascaridole was ig administered with the dosages of 10 and 20 mg/kg once daily for 7 d.Results Ascaridole showed the significant anti-ulcer effects.In acetic acid-induced gastric ulcer rats,the ulcer areas after 10 and 20 mg/kg of ascaridole treatment were (65.1 ± 20.0) and (50.6 ± 11.0) mm2,respectively,which were significant lower (P < 0.01) than that of the control group [(116.7 ± 35.8) mm2].For pylorus ligation model,ascaridole showed a gastric ulcer healing effect in a dose-dependent manner.Ascaridole at the dose of 20 mg/kg showed 50% ulcer protection and had a significant (P < 0.05) gastroprotective activity since it decreased the total acidity and pepsin activity.Compared to the control group,the two dosages of ascaridole showed the significant reduction (P < 0.05) in the ulcer index on Aspirin-induced ulcer.ConclusionThis study provides evidence that ascaridole shows potential efficacy on the healing of gastric ulcers induced by acetic acid,Aspirin,and pylorus ligation.

7.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-425155

RESUMO

Objective To observe the changes of serum bilirubin(BIL) and high-sensitivity C-reactive protein(hs-CRP) after percutaneous coronary intervention(PCI) in acute myocardial infarction(AMI) patients.Methods The TBiI,IBil,DBil and hs-CRP levels in serum were detected in 60 AMI patients within 6 hours after attack with immunoturbidimetry before PCI,at the point of operation,6h,12h,24h,72h and 7d afer PCI.30 healthy persons were chosen as normal control.The two groups were compared.Results The hs-CRP level was increased gradually with time in AMI patients after PCI.The peak value was at 72h after PCI and it was significantly higher than those in the normal group( P < 0.05 ).The TBil,IBil,DBil levels at pre-PCI point were significantly lower than the normal group (P < 0.05).These index were gradually recovered to the normal group and no significancet differences between them (P > 0.05 ).The coefficient correlation of hs-CRP and TBil,IBil,DBil were 0.44 ( P > 0.05 ).Conclusion The TBil,IBil,DBil and hs-CRP levels in short time after attack of AMI with PCI presented a dynamic changing and recovered to the normal level.No associativity was observed between them,but as the follow-up index,it was significant for the disease turnover.

8.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-386178

RESUMO

Objective To investigate the clinical significance and relationship of preS1, HBV DNA and HBV-M. Methods PreS1 and HBV-M was detected by ELISA method,and HBV DNA was detected by PCR. Then the results were analyzed. Results In HBV patients,the positive rates of preS1 and HBV DNA had no statistically significant ,they had fine dependability. The detection rate of preS1 in HBeAg(+) group(80.3%) and HBeAg(+)group( 56.3% ) had statistically significant. In some patients,though HBeAg had become negative, HBV still replicated. In HBV DNA replicated patients(≥103 copies/ml) ,the detection rate of HBeAg and preS1 were 51.5% and 70.9% ,they had statistically significant. Conclusion HBV DNA and PreS1 had fine dependability,preSl could reflect the replication of HBV sensitively than HBeAg,it could be used as a reliable new marker of HBV replication in vivo.

9.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-589036

RESUMO

Objective To explore the diagnostic value of cystatin C(CysC) on early kidney damage in primary hypertension. Method To detect the CysC, BUN, Scr, UA in Ⅰ (31), Ⅱ (31), Ⅲ (31) stage of primary hypertension patients and 40 control cases ,then compared these results with normal control. Results The level of CysC in serum of Ⅰ , Ⅱ, Ⅲ stage of primary hypertension was(0. 81 ± 0. 16), (0. 94 ± 0. 23), (1.19 ± 0. 46) mmg/L, all of them were higher than normal control (0. 75 ± 0. 10) mg/L. The difference of CysC between Ⅱ、Ⅲ stage of primary hypertension and normal control was significant (t = 4. 195, t = 4. 446, P < 0.01). The level of CysC in Ⅲ stage of primary hypertension was higher than in Ⅰ , Ⅱ stage(t = 4. 382 ,t = 4. 250,P < 0.01). Significant positive correlation was observed between CysC and Scr(r = 0. 713,P<0.01) ,CysC and UA(r=0. 45,P <0.01). Conclusion Serum CysC was a sensitive and reliable indicator on early kidney function damage in primary hypertension.

10.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-266396

RESUMO

In order to construct recombinant baculovirus carrying Schistosoma japonicum 26 ku glutathione S-transferase gene (Sj26), and observe the expression of Sj26 in mammalian cells, the Sj26 gene was amplified with plasmid pGEX-3X as template by PCR, and then recombined into Tvector for sequencing. Sj26 gene was inserted into the downstream of CMV promoter of donor plasmid pFBDGC, and the recombinant donor plasmid pFBDGC-Sj26 transformed into DH10Bac,then the recombinant bacmid AcCMVSj26 was isolated and transfected into Sf9 cells. The recombinant baculovirus was harvested and final titer of vAcCMVSj26 was measured. BHK cells were transducted with recombinant baculovirus in vitro. By using Western blot, the expression of 26 ku glutathione S-transferase (GST) was detected. The results showed that after enzyme digestion and sequencing, the donor plasmid was successfully constructed. PCR confirmed that pFBDGC-Sj26 and Bacmid homologous recombination occurred in E. coli. After transfection of Sf9 cells with recombinant Bacmid, recombinant baculovirus was replicated in Sf9 cells and expressed green fluorescent protein. PCR further revealed recombinant baculovirus contained Sj26. The titer of the harvested baculovirus was 1.24 × 108. Western blot demonstrated that recombinant baculovirus could express 26 ku GST in BHK cells. It was concluded that Sj26 recombinant baculovirus was successfully constructed, and the 26 ku GST was expressed in mammalian cells.

11.
Artigo em Inglês | WPRIM (Pacífico Ocidental) | ID: wpr-634337

RESUMO

In order to construct recombinant baculovirus carrying Schistosoma japonicum 26 ku glutathione S-transferase gene (Sj26), and observe the expression of Sj26 in mammalian cells, the Sj26 gene was amplified with plasmid pGEX-3X as template by PCR, and then recombined into T vector for sequencing. Sj26 gene was inserted into the downstream of CMV promoter of donor plasmid pFBDGC, and the recombinant donor plasmid pFBDGC-Sj26 transformed into DH10Bac, then the recombinant bacmid AcCMVSj26 was isolated and transfected into Sf9 cells. The recombinant baculovirus was harvested and final titer of vAcCMVSj26 was measured. BHK cells were transducted with recombinant baculovirus in vitro. By using Western blot, the expression of 26 ku glutathione S-transferase (GST) was detected. The results showed that after enzyme digestion and sequencing, the donor plasmid was successfully constructed. PCR confirmed that pFBDGC-Sj26 and Bacmid homologous recombination occurred in E. coli. After transfection of Sf9 cells with recombinant Bacmid, recombinant baculovirus was replicated in Sf9 cells and expressed green fluorescent protein. PCR further revealed recombinant baculovirus contained Sj26. The titer of the harvested baculovirus was 1.24 x 10(8). Western blot demonstrated that recombinant baculovirus could express 26 ku GST in BHK cells. It was concluded that Sj26 recombinant baculovirus was successfully constructed, and the 26 ku GST was expressed in mammalian cells.

12.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-582132

RESUMO

Objective To evaluate the effect of albendazole immunoliposome (IL-Alb) against Echinococcus granulosus. Methods Mice infected with protoscolices of E.granulosus were divided into five groups. Four groups were treated with albendazole (Alb), albendazole liposome (L-Alb), albendazole sulfoxide liposome (L-Albso), and IL-Alb respectively at a dosage of 100 mg (Alb)/(kg?d)?5 d for 3 courses. The fifth group was established as control. The major criteria for evaluating the effects included a reduction rate of E.granulosus tissue wet weight, histopathological examination of the cysts by both light microscopy and electron-microscopy, and the content of albendazole-sulfoxide in cysts detected by HPLC. Results The efficacy of albendazole immunoliposome was significantly higher than that of albendazole liposome, and much higher than that of albendazole. The reduction rates of cyst tissue weight of IL-Alb group, L-Alb group and Alb group were 91^5%, 80^3%, 61^2% respectively as compared to control group; the concentration of Albso in cyst tissue of the above groups were 5^15 ?g/g, 2^18 ?g/g, 0^76 ?g/g respectively (P

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