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1.
Boran cattle were immunized with a semi-purified fraction (F2) of solubilized membrane-bound antigens extracted from the midgut of the tickRhipicephalus appendiculatus. A subsequent challenge with all stages ofR. appendiculatus showed protection of the cattle to a significant degree. There was a decrease in engorgement weight of ticks, the number which fed above critical engorgement weight was considerably reduced, and about 38% of the larvae which fed to repletion did not moult. The major cause of death of adult female ticks was the increased grooming by cattle as a result of increased dermal irritation.  相似文献   
2.
The penicillin derivative amoxicillin (AMX) plays an important role in treating various types of infections caused by bacteria. However, excessive use of AMX may have negative health effects. Therefore, it is of utmost importance to detect and quantify the AMX in pharmaceutical drugs, biological fluids, and environmental samples with high sensitivity. Therefore, this review article provides valuable and up-to-date information on nanostructured material-based optical and electrochemical sensors to detect AMX in various biological and chemical samples. The role of using different nanostructured materials on the performance of important optical sensors such as colorimetric sensors, fluorescence sensors, surface-enhanced Raman scattering sensors, chemiluminescence/electroluminescence sensors, optical immunosensors, optical fibre-based sensors, and several important electrochemical sensors based on different electrode types have been discussed. Moreover, nanocomposites, polymer, and MXenes-based electrochemical sensors have also been discussed, in which such materials are being used to further enhance the sensitivity of these sensors. Furthermore, nanocomposite-based photo-electrochemical sensors and the market availability of biosensors including AMX have also been discussed briefly. Finally, the conclusion, challenges, and future perspectives of the above-mentioned sensing techniques for AMX detection are presented.  相似文献   
3.
Colon cancer is one of the most common causes of deaths by cancer worldwide. Stem cells have immunosuppressive properties that promote tumor targeting and circumvent obstacles currently in gene therapy. Bone marrow stem cells are believed to have anticancer potential. The transplantation of mesenchymal stem cells (MSCs), a type of bone marrow stem cells, has been considered a potential therapy for patients with solid tumors due to their capability to enhance the immune response; MSC transplantation has received renewed interest in recent years. The present study aimed to evaluate the antiapoptotic effects of the MSCs on 1,2-dimethylhydrazine (DMH)-induced inflammation in the rat model of colorectal cancer. The rats were randomly allocated into four groups: control, treated with MSCs, induced by DMH, and induced by DMH and treated with MSCs. The MSCs were intra-rectally injected, and DMH was subcutaneously injected at 20 mg/kg body weight once a week for 15 weeks. The administration of MSCs into rats starting from day 0 of the DMH injection was found to enhance the histopathological picture. The MSC treatment resulted in fewer inflammatory cells than in the DMH group. Therefore, our findings suggest that BMCs have antitumor effects by modulating the cellular redox status and down-regulating the pro-inflammatory genes. Thus, BMCs may provide therapeutic value for colon cancer treatment.  相似文献   
4.
Abstract

High-throughput sequencing approach of the 16S rRNA gene was employed to evaluate the bacterial diversity inhabit in melted water, snow, soil, and rocks samples at the lower altitudes of the Laohugou glacial environment. Bioinformatics tools were used to process millions of Illumina reads for alpha and beta diversities of bacterial communities. The diversity indices such as Chao, Shannon, and Simpson were different in the collected samples and solid samples (soil and rocks) showed higher taxon richness and evenness. Taxonomic diversity was unexpectedly higher and the major portion of sequences was assigned to Proteobacteria, Actinobacteria, and Acidobacteria. Higher variation in community structure was reported at the class level and Alphaproteobacteria was dominant. The solid niches were occupied by a higher number of phyla compared with liquid. The physicochemical variables acted as spatial gradients and associated with the bacterial structural communities of the glacial ecosystem. Findings showed that both Proteobacteria and Actinobacteria in solid samples influenced the bacterial community structure in downstream liquid samples. Interestingly, the metagenomic biomarkers were higher in liquid samples. This study provides precious datasets to understand the bacterial community in a better way under the influence of spatial, physical and environmental factors.  相似文献   
5.
Activation-induced cytidine deaminase (AID) deaminates deoxycytidine (dC) to deoxyuracil (dU) at immunoglobulin loci in B lymphocytes to mediate secondary antibody diversification. Recently, AID has been proposed to also mediate epigenetic reprogramming by demethylating methylated cytidines (mC) possibly through deamination. AID overexpression in zebrafish embryos was shown to promote genome demethylation through G:T lesions, implicating a deamination-dependent mechanism. We and others have previously shown that mC is a poor substrate for human AID. Here, we examined the ability of bony fish AID to deaminate mC. We report that zebrafish AID was unique among all orthologs in that it efficiently deaminates mC. Analysis of domain-swapped and mutant AID revealed that mC specificity is independent of the overall high-catalytic efficiency of zebrafish AID. Structural modeling with or without bound DNA suggests that efficient deamination of mC by zebrafish AID is likely not due to a larger catalytic pocket allowing for better fit of mC, but rather because of subtle differences in the flexibility of its structure.  相似文献   
6.
ABSTRACT

Inhibitors of monoamine oxidase (MAO)-B have been used for many years in the therapy of Parkinson’s disease (PD). Owing to the safety concerns of the currently used agents, the discovery of novel scaffolds is of considerable interest. MAO-B inhibitory potential of rutin, a flavonoid derived from natural sources, has been established in experimental findings. Hence, the current study seeks to examine the interactions between rutin and crystal structure of human MAO-B enzyme. Molecular docking calculations, as well as molecular dynamics simulations, were employed to investigate the binding mode and the stability of the rutin/MAO-B complex. Energies of highest occupied/lowest unoccupied molecular orbitals were computed through DFT studies and used to calculate electron affinity, hardness, chemical potential, electronegativity, and electrophilicity index in order to investigate the capability of these parameters to influence the ligand–receptor interactions. It was found that rutin traverses both the entrance cavity and the substrate cavity, forcing the Ile-199 ‘gate’ to rotate into its open conformation. It results in the fusion of the two cavities of the MAO-B binding site and directly leads to better binding interactions. Results of the current study can be used for lead modification and development of novel drugs for the treatment of PD.  相似文献   
7.
Middle East respiratory syndrome coronavirus (MERS-CoV) causes severe acute respiratory infection with as yet unclear epidemiology. We previously showed that MERS-CoV counteracts parts of the innate immune response in human bronchiolar cells. Here we analyzed accessory proteins 3, 4a, 4b, and 5 for their abilities to inhibit the type I interferon response. Accessory protein 4a was found to block interferon induction at the level of melanoma differentiation-associated protein 5 (MDA5) activation presumably by direct interaction with double-stranded RNA.  相似文献   
8.
Reactive oxygen and nitrogen species such as superoxide and nitric oxide are released into the extracellular spaces by inflammatory and airway epithelial cells. These molecules may exacerbate lung injury after influenza virus pneumonia. We hypothesized that enhanced expression of extracellular superoxide dismutase (EC SOD) in mouse airways would attenuate the pathological effects of influenza pneumonia. We compared the pathogenic effects of a nonlethal primary infection with mouse-adapted Hong Kong influenza A/68 virus in transgenic (TG) EC SOD mice versus non-TG (wild-type) littermates. Compared with wild-type mice, EC SOD TG mice showed less lung injury and inflammation as measured by significant blunting of interferon-gamma induction, reduced cell count and total protein in bronchoalveolar lavage fluid, reduced levels of lung nitrite/nitrate nitrotyrosine, and markedly reduced lung pathology. These results demonstrate that enhancing EC SOD in the conducting and distal airways of the lung minimizes influenza-induced lung injury by both ameliorating inflammation and attenuating oxidative stress.  相似文献   
9.
10.
Fanconi anemia (FA) is an autosomal recessive cancer susceptibility syndrome with at least eight complementation groups (A-H). Two of the FA genes (FAA and FAC) have been cloned, and mutations in these genes account for approximately 80% of FA patients. Subtyping of FA patients is an important first step toward identifying candidates for FA gene therapy. In the current study, we analyzed a reference group of 26 FA patients of known subtype. Most of the patients (18/26) were confirmed as either type A or type C by immunoblot analysis with anti-FAA and anti-FAC antisera. In order to resolve the subtype of the remaining patients, we generated retroviral constructs expressing FAA and FAC for transduction of FA cell lines (pMMP-FAA and pMMP-FAC). The pMMP-FAA construct specifically complemented the abnormal phenotype of cell lines from FA-A patients, while pMMP-FAC complemented FA-C cells. In summary, the combination of immunoblot analysis and retroviral-mediated phenotypic correction of FA cells allows a rapid method of FA subtyping.  相似文献   
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