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1.
This study assessed the natural killer (NK) cell activity profile during Plasmodium cynomolgi infection in rhesus monkeys. There was a significant decrease in the NK cell activity in the peripheral blood leukocytes of infected monkeys during the early, ascending phase of infection. However, as the parasite load decreased, NK cell activity returned to normal levels. This could be correlated with the peak increase in lymphocyte counts. This indicated that a decrease in NK cell activity observed at an earlier stage during an active P. vivax malarial infection was a temporary phenomenon. 相似文献
2.
S. Raj V. Vinod J. Jayakumar P. Suresh A. Kumar R. Biswas 《Letters in applied microbiology》2021,73(1):31-38
Candida species are opportunistic human fungal pathogens that cause acute and chronic infections against which only few antifungal agents are available. Here we have elucidated the antifungal effect of Syzygium samarangense leaf extracts (SSLE). Antifungal activity of SSLE was studied against Candida albicans, C. krusei, C. parapsilosis, C. glabrata, C. auris and C. tropicalis. Following experiments were performed: minimum fungicidal concentration (MFC) determination, agar well disc diffusion assays, fungal morphology analysis using scanning electron microscope (SEM), ex vivo fungal survival assays on porcine tongue and skin and in vivo fungal survival assays using Drosophila melanogaster fly model. Results demonstrated MFC of SSLE ranges between 100 and 125 mg ml−1. SEM images showed cell wall degradation of C. albicans when treated with SSLE. Around 75% decrease in C. albicans viability was observed when infected porcine tongue and skin were treated using SSLE. The C. albicans infected D. melanogaster when fed with SSLE showed significant decrease (around 80%) of fungal count than the infected control. Furthermore, agar plate disc diffusion assays demonstrated that the antifungal activity of SSLE could be due to chalcone, which is one of the active constituents in SSLE. Our study demonstrated that SSLE could be used for the topical treatment of Candida infections. 相似文献
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The solitons in α-helix proteins that are governed by the nonlinear Schrödinger’s equation is investigated in presence of perturbation terms in this paper. The integration of this perturbed nonlinear Schrödinger’s equation is carried out. The solitary wave ansatz is used to carry out the integration and the parameter domain is identified. 相似文献
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Abstract A highly sensitive nested polymerase chain reaction method was designed for the detection of a wide spectrum of strains from Borrelia burgdorferi sensu lato. This technique allows the detection of as little as 3 fg of total genomic DNA extracted and purified from pure cultures of the organism, this amount corresponds to less than 10 organisms. Two sets of primers homologous to conserved spots in the coding region of the hbb gene, encoding a conserved histone-like protein, were constructed. These were based on a multiple sequence alignment of 39 strains representing all the genomic groups described in B. burgdorferi sensu lato. 相似文献
8.
Abstract This study assessed the natural killer (NK) cell activity profile during Plasmodium cynomologi infection in rhesus monkeys. There was a significant decrease in the NK cell activity in the peripheral blood leukocytes of infected monkeys during the early, asending phase of infection. However, as the parasite load decreased, NK cell activity returned to normal levels. This could be correlated with the peak increase in lymphocyte counts. This indicated that a decrease in NK cell activity observed at an earlier stage during an active P. vivax malarial infection was a temporary phenomenon. 相似文献
9.
Experimental infection of hamsters with Leishmania donovani caused visceral leishmaniasis in which hematological changes occurred. The infected hamsters were anemic and reticulocyte counts were high. No significant change in the serum erythropoietin level was noted. Red cell membrane Na(+)-K(+)-ATPase and acetylcholinesterase activities increased. Osmotic fragility of the erythrocytes from infected animals increased. The level of 2,3-diphosphoglycerate of the red cells increased with the degree of anemia. 相似文献
10.
Cloning and characterization of thermotolerant xylitol dehydrogenases from yeast Pichia angusta 总被引:1,自引:0,他引:1
Dipanwita Biswas Manish Datt Kaliannan Ganesan Alok K. Mondal 《Applied microbiology and biotechnology》2010,88(6):1311-1320
Pichia angusta (syn. Hansenula polymorpha) represents one of the rare yeast that can grow and ferment both xylose and glucose at higher temperature (50°C). However,
little is known about the enzymes involved in xylose utilization from this species. Previous studies indicated the presence
of one xylose reductase and two xylitol dehydrogenase genes in P. angusta. In this study, we have expressed both xylitol dehydrogenases (PaXdh1p and PaXdh2p) in Escherichia coli and purified them as 6X-Histidine-tagged proteins. Biochemical characterization of the recombinant proteins reveals that
both PaXdh1p and PaXdh2p are thermotolerant enzymes. PaXdh2p contains a catalytic and a structural Zn atom. However, the structural
Zn atom is not present in PaXdh1p. Both enzymes also differ in their affinity for the substrate as well as in the catalytic
efficiency. Through mutagenesis and modeling approaches, we have also identified residues important for catalysis and substrate
binding. 相似文献