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31.

Background  

Malaria parasite secretes various proteins in infected RBC for its growth and survival. Thus identification of these secretory proteins is important for developing vaccine/drug against malaria. The existing motif-based methods have got limited success due to lack of universal motif in all secretory proteins of malaria parasite.  相似文献   
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Fusarium infection of bananas is a global problem that threatens the production of bananas. This study looks at the effects of the infection upon the reactive oxygen species (ROS) system, as well as the induced antioxidant properties in the roots, stems, leaves and fruits. Results show that there is a greater amount of damage in infected tissue samples as opposed to non‐infected. The damage was observed to be higher in the root samples. ROS assays were divided into two classes: ROS assays and ROS‐scavenging assays. Of the ROS assays, lipoxygenase was observed to be higher in the infected samples, while peroxidase (POD) and polyphenol oxidase (PPO) were significantly higher in infected stem, leaf and fruit samples. Among root samples, there was no significant difference in POD activity and PPO was lower in infected samples. Induction of ROS is important for the hypersensitive response (HR) to function properly. The ROS‐scavenging enzymes, namely ascorbate peroxidase, guaiacol peroxidase and superoxide dismutase, exhibited higher levels in the infected tissue. This is most likely to counter the build‐up of the ROS enzymes and to prevent further cell death. The increase in ROS‐scavenging assays also correlates with higher antioxidant properties as antioxidants play a critical role in regulating the HR free radicals.  相似文献   
34.
Ovarian cancer continues to be a difficult medical issue that affects millions of individuals worldwide. Important platforms for cancer immunotherapy include checkpoint inhibitors, chimeric antigen receptor T cells, bispecific antibodies, cancer vaccines, and other cell-based treatments. To avoid numerous infectious illnesses, conventional vaccinations based on synthetic peptides, recombinant subunit vaccines, and live attenuated and inactivated pathogens are frequently utilized. Vaccine manufacturing processes, however, are not entirely safe and carry a significant danger of contaminating living microorganisms. As a result, the creation of substitute vaccinations is required for both viral and noninfectious illnesses, including cancer. Recently, there has been testing of nucleic acid vaccines, or NAVs, as a cancer therapeutic. Tumor antigens (TAs) are genetically encoded by DNA and mRNA vaccines, which the host uses to trigger immune responses against ovarian cancer cells that exhibit the TAs. Despite being straightforward, safe, and easy to produce, NAVs are not currently thought to be an ideal replacement for peptide vaccines. Some obstacles to this strategy include selecting the appropriate therapeutic agents (TAs), inadequate immunogenicity, and the immunosuppressive characteristic of ovarian cancer. We focus on strategies that have been employed to increase NAVs' effectiveness in the fight against ovarian cancer in this review.  相似文献   
35.
In this article, we have reported the effect of varying concentration of europium (Eu) in (50 − x)% P2O5–25% Na2O–24% CaO–% Eu2O3, where x = 1, 3, 5. The glass samples were synthesised via conventional melt-quench method. The impact of europium ion (Eu3+) on the structural, optical and luminescent properties of phosphate soda lime glasses has been studied using X-ray diffraction (XRD), Fourier-transformed infrared (FTIR) spectroscopy, ultraviolet-visible spectroscopy, scanning electron microscopy coupled with energy-dispersive spectroscopy and photoluminescent techniques. The amorphous nature of glass samples was confirmed by XRD patterns. FTIR confirmed the presence of various functional groups. The emission spectra of synthesised samples exhibited intense emission peaks corresponding to Eu3+ under excitation at 393 nm. Among all the peaks, the maximum intensity was observed for 5D07F2 transition. Judd–Ofelt (J–O) parameters (Ω2, Ω4) and other radiative parameters such as band width, radiative transition probabilities, stimulated emission cross-sections and branching ratio were determined from emission spectra. The other photometric parameters such as CIE coordinates and colour purity were also determined. Furthermore, cytotoxic studies were carried out on normal cell line human embryonic kidney cells (HEK-293) using MTT assay. Results showed that the prepared samples significantly enhanced growth in glass sample-treated cells as compared to control cells. These findings suggest that synthesised glass samples are biocompatible in nature and have potential for applications in display devices and biomedical research area.  相似文献   
36.
BackgroundThe prevalence of Strongyloides stercoralis infection is estimated to be 30–100 million worldwide, although this an underestimate. Most cases remain undiagnosed due to the asymptomatic nature of the infection. We wanted to estimate the seroprevalence of S. stercoralis infection in a South Indian adult population.MethodsTo this end, we performed community-based screening of 2351 individuals (aged 18–65) in Kanchipuram District of Tamil Nadu between 2013 and 2020. Serological testing for S. stercoralis was performed using the NIE ELISA.ResultsOur data shows a seroprevalence of 33% (768/2351) for S. stercoralis infection which had a higher prevalence among males 36% (386/1069) than among females 29.8% (382/1282). Adults aged ≥55 (aOR = 1.65, 95% CI: 1.25–2.18) showed higher adjusted odds of association compared with other age groups. Eosinophil levels (39%) (aOR = 1.43, 95% CI: 1.19–1.74) and hemoglobin levels (24%) (aOR = 1.25, 95% CI: 1.11–1.53) were significantly associated with S. stercoralis infection. In contrast, low BMI (aOR = 1.15, 95% CI: 0.82–1.61) or the presence of diabetes mellitus (OR = 1.18, 95% CI: 0.83–1.69) was not associated with S. stercoralis seropositivity.ConclusionsOur study provides evidence for a very high baseline prevalence of S. stercoralis infection in South Indian communities and this information could provide realistic and concrete planning of control measures.  相似文献   
37.
Factors shaping the distribution and abundance of species include life‐history traits, population structure, and stochastic colonization–extinction dynamics. Field studies of model species groups help reveal the roles of these factors. Species of Caenorhabditis nematodes are highly divergent at the sequence level but exhibit highly conserved morphology, and many of these species live in sympatry on microbe‐rich patches of rotten material. Here, we use field experiments and large‐scale opportunistic collections to investigate species composition, abundance, and colonization efficiency of Caenorhabditis species in two of the world''s best‐studied lowland tropical field sites: Barro Colorado Island in Panamá and La Selva in Sarapiquí, Costa Rica. We observed seven species of Caenorhabditis, four of them known only from these collections. We formally describe two species and place them within the Caenorhabditis phylogeny. While these localities contain species from many parts of the phylogeny, both localities were dominated by globally distributed androdiecious species. We found that Caenorhabditis individuals were able to colonize baits accessible only through phoresy and preferentially colonized baits that were in direct contact with the ground. We estimate the number of colonization events per patch to be low.  相似文献   
38.
Galston , Arthur W., Ravindar Kaur , Nirmala Maheshwari , and Satish C. Maheshwari . (Yale U., New Haven, Conn.) Pectin-protein interaction as a basis for au xin-induced alteration of protein heat coagulability. Amer. Jour. Bot. 50(5): 487–494. Illus. 1963.—The in vivo administration of 2,4-D or other auxins to etiolated or green pea stem sections results in a decreased heat coagulability of the macromolecular components of the particle-free cytoplasm of these tissues. Addition of auxin to homogenates is without effect. Gibberellins alone are also without effect, but may enhance the in vivo action of auxin. The altered heat coagulability may become apparent as soon as 4–6 hr after auxin administration, though longer induction periods are sometimes necessary. The auxin eff'ect is prevented by general metabolic inhibitors and most effectively by ethionine, whose inhibitory action is completely reversed by methionine. Electrophoresis on paper and on starch revealed no major differences between the proteins of control and auxin-treated stems. Approximately 90% of the weight of the heat coagulum can be accounted for as protein; small quantities of nucleic acids, lipids, polysaccharides and pectins are also present. The “soluble pectin” content of the homogenate before heat coagulation is at least doubled by auxin treatment. This increase is also inhibited by ethionine, whoso effect is annulled by methionine. Addition of citrus pectin to control homogenates stabilizes the proteins against heat coagulation. It thus appears likely that the effect of auxin on the heat coagulability of the cytoplasmic proteins can be explained through effects on the metabolism of the materials which have been called “cold-water-soluble pectins.”  相似文献   
39.
International Journal of Peptide Research and Therapeutics - Bioactive peptides have been reported to exhibit opioid-like activity and are termed as opioid peptides. Either these are produced...  相似文献   
40.
Singh  Ashutosh  Singh  Rahul Soloman  Sarma  Phulen  Batra  Gitika  Joshi  Rupa  Kaur  Hardeep  Sharma  Amit Raj  Prakash  Ajay  Medhi  Bikash 《中国病毒学》2020,35(3):290-304
The recent outbreak of coronavirus disease(COVID-19) caused by the novel severe acute respiratory syndrome coronavirus 2(SARS-CoV-2) has already affected a large population of the world. SARS-CoV-2 belongs to the same family of severe acute respiratory syndrome coronavirus(SARS-CoV) and Middle East respiratory syndrome coronavirus(MERSCoV). COVID-19 has a complex pathology involving severe acute respiratory infection, hyper-immune response, and coagulopathy. At present, there is no therapeutic drug or vaccine approved for the disease. There is an urgent need for an ideal animal model that can reflect clinical symptoms and underlying etiopathogenesis similar to COVID-19 patients which can be further used for evaluation of underlying mechanisms, potential vaccines, and therapeutic strategies. The current review provides a paramount insight into the available animal models of SARS-CoV-2, SARS-CoV, and MERS-CoV for the management of the diseases.  相似文献   
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