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11.
Context: Metabolic imbalance in renal cell carcinoma (RCC) can lead to abnormal adiponectin levels.

Objective: To evaluate circulating adiponectin as a detection or predictive marker for RCC.

Methods: A comprehensive literature search and meta-analysis was performed on studies reporting circulating adiponectin levels and RCC. The meta-analysis was performed using RevMan.

Results: Seven studies compared the circulating adiponection levels between RCC cases and controls. Adiponectin level was significantly lower in RCC cases compared to controls at pre-diagnosis and pre-operative time-points. RCC stage, grade and subtype did not affect adiponectin levels.

Conclusion: Low circulating adiponectin could be a predictive or risk factor for RCC.  相似文献   

12.
Depletion of CpG dinucleotides in severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) genomes has been linked to virus evolution, host-switching, virus replication, and innate immune responses. Temporal variations, if any, in the rate of CpG depletion during virus evolution in the host remain poorly understood. Here, we analyzed the CpG content of over 1.4 million full-length SARS-CoV-2 genomes representing over 170 million documented infections during the first 17 months of the pandemic. Our findings suggest that the extent of CpG depletion in SARS-CoV-2 genomes is modest. Interestingly, the rate of CpG depletion is highest during early evolution in humans and it gradually tapers off, almost reaching an equilibrium; this is consistent with adaptations to the human host. Furthermore, within the coding regions, CpG depletion occurs predominantly at codon positions 2-3 and 3-1. Loss of ZAP (Zinc-finger antiviral protein)-binding motifs in SARS-CoV-2 genomes is primarily driven by the loss of the terminal CpG within the motifs. Nonetheless, majority of the CpG depletion in SARS-CoV-2 genomes occurs outside ZAP-binding motifs. SARS-CoV-2 genomes selectively lose CpGs-motifs from a U-rich context; this may help avoid immune recognition by TLR7. SARS-CoV-2 alpha-, beta-, and delta-variants of concern have reduced CpG content compared to sequences from the beginning of the pandemic. In sum, we provide evidence that the rate of CpG depletion in virus genomes is not uniform and it greatly varies over time and during adaptations to the host. This work highlights how temporal variations in selection pressures during virus adaption may impact the rate and the extent of CpG depletion in virus genomes.  相似文献   
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In a SAR study, we have synthesized a few 1H-pyrazole carboxylate related microbicides using Vilsmeier reagent. The anti-microbial screening results of 1H-pyrazole-3-carboxylate are reported here for the first time. The effect of 1H-pyrazole carboxylates on the mycelial growth of plant pathogenic fungi is revealed. The first X-ray structure in the family of microbicidal 1H-pyrazole-4-carboxylates is presented.  相似文献   
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Wheat (Triticum aestivum) plants were stably transformed with the coat protein (CP) gene of wheat streak mosaic virus (WSMV) by the biolistic method. Eleven independently transformed plant lines were obtained and five were analyzed for gene expression and resistance to WSMV. One line showed high resistance to inoculations of two WSMV strains. This line had milder symptoms and lower virus titer than control plants after inoculation. After infection, new growth did not show symptoms. The observed resistance was similar to the recovery type resistance described previously using WSMV NIb transgene and in other systems. This line looked morphologically normal but had an unusually high transgene copy number (approximately 90 copies per 2C homozygous genome). Northern hybridization analysis indicated a high level of degraded CP mRNA expression. However, no coat protein expression was detected.  相似文献   
17.
Transgenic groundnut (Arachis hypogaea L.) plants were produced efficiently by inoculating different explants withAgrobacterium tumefaciens strain LBA4404 harbouring a binary vector pBM21 containinguidA (GUS) andnptll (neomycin phosphotransferase) genes. Genetic transformation frequency was found to be high with cotyledonary node explants followed by 4 d cocultivation. This method required 3 days of precultivation period before cocultivation withAgrobacterium. A concentration of 75 mg/l kanamycin sulfate was added to regeneration medium in order to select transformed shoots. Shoot regeneration occurred within 4 weeks; excised shoots were rooted on MS medium containing 50 mg/I kanamycin sulfate before transferring to soil. The expression of GUS gene (uidA gene) in the regenerated plants was verified by histochemical and fluorimetric assays. The presence ofuidA andnptll genes in the putative transgenic lines was confirmed by PCR analysis. Insertion of thenptll gene in the nuclear genome of transgenic plants was verified by genomic Southern hybridization analysis. Factors affecting transformation efficiency are discussed.  相似文献   
18.
This study was designed to evaluate the effect of phytohormones on plant regeneration from epicotyl and hypocotyl explants of two groundnut (Arachis hypogaea) cultivars. Explants cultured on media with auxins and in combination with cytokinin produced high frequency of callus. After four weeks, callus from these cultures was transferred to medium with cytokinin and reduced auxin, shoot buds regenerated from the cultures. A high rate of shoot bud regeneration was observed on medium supplemented with 2.0 mg/L BAP and 0.5 mg/L NAA. Among the different auxins tested, NAA was found to be most effective, producing the highest frequency of shoot buds per responding cultures. Of the two explants tested, epicotyl was found to be best for high frequency shoot bud regeneration. Multiple shoots arose on MS medium supplemented with BAP or kinetin (1.0–5.0 mg/L) plus IBA (1.0 mg/L), with maximum production occurring at 5.0 mg/L. The elongated shoots developed rootsin vitro upon transfer to MS medium supplemented with NAA or IBA (0.5–2.0 mg/L) and kinetin (0.5 mg/L) for 15 days.In vitro produced plantlets, were transferred to soil and placed in a glasshouse developed successfully, matured, and set seeds.  相似文献   
19.
Cation–π interaction is a non-covalent binding force that plays a significant role in protein stability and drug–receptor interactions. In this work, we have investigated the structural role of cation–π interactions in sugar-binding proteins (SBPs). We observed 212 cation–π interactions in 53 proteins out of 59 SBPs in dataset. There is an average one energetically significant cation–π interaction for every 66 residues in SBPs. In addition, Arg is highly preferred to form cation–π interactions, and the average energy of Arg-Trp is high among six pairs. Long-range interactions are predominant in the analyzed cation–π interactions. Comparatively, all interaction pairs favor to accommodate in strand conformations. The analysis of solvent accessible area indicates that most of the aromatic residues are found on buried or partially buried whereas cationic residues were found mostly on the exposed regions of protein. The cation–π interactions forming residues were found that around 43% of cation–π residues had highly conserved with the conservation score ≥6. Almost cationic and π-residues equally share in the stabilization center. Sugar-binding site analysis in available complexes showed that the frequency of Trp and Arg is high, suggesting the potential role of these two residues in the interactions between proteins and sugar molecules. Our observations in this study could help to further understand the structural stability of SBPs.  相似文献   
20.
AIMS: Venoms of snakes, scorpions, bees and purified venom phospholipase A(2) (PLA(2)) enzymes were examined to evaluate the antibacterial activity of purified venom enzymes as compared with that of the crude venoms. METHODS AND RESULTS: Thirty-four crude venoms, nine purified PLA(2)s and two L-amino acid oxidases (LAAO) were studied for antibacterial activity by disc-diffusion assay (100 microg ml(-1)). Several snake venoms (Daboia russelli russelli, Crotalus adamanteus, Naja sumatrana, Pseudechis guttata, Agkistrodon halys, Acanthophis praelongus and Daboia russelli siamensis) showed activity against two to four different pathogenic bacteria. Daboia russelli russelli and Pseudechis australis venoms exhibited the most potent activity against Staphylococcus aureus, while the rest showed only a moderate activity against one or more bacteria. The order of susceptibility of the bacteria against viperidae venoms was -S. aureus > Proteus mirabilis > Proteus vulgaris > Enterobacter aerogenes > Pseudomonas aeruginosa and Escherichia coli. The minimum inhibitory concentrations (MIC) against S. aureus was studied by dilution method (160-1.25 microg ml(-1)). A stronger effect was noted with the viperidae venoms (20 microg ml(-11)) as compared with elapidae venoms (40 microg ml(-1)). The MIC were comparable with those of the standard drugs (chloramphenicol, streptomycin and penicillin). CONCLUSION: The present findings indicate that viperidae (D. russelli russelli) and elapidae (P. australis) venoms have significant antibacterial effects against gram (+) and gram (-) bacteria, which may be the result of the primary antibacterial components of laao, and in particular, the PLA(2) enzymes. The results would be useful for further purification and characterization of antibacterial agents from snake venoms. SIGNIFICANCE AND IMPACT OF THE STUDY: The activity of LAAO and PLA(2) enzymes may be associated with the antibacterial activity of snake venoms.  相似文献   
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