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1.
Two new species of Chronogaster in India were described and illustrated, based on light and scanning electron microscopy. Chronogaster neotypica n. sp. collected from a sewage slurry was characterized by a medium-sized body, a ventral tail mucro without additional spines, absence of longitudinal incisures in lateral fields, and by the presence of crystalloids in the body. Diagnostic for C. spinicauda n. sp. collected from soil around roots of mango were a medium-sized body, a tail mucro with 10 spines, and absence of lateral lines and crystalloids. Males were not found.  相似文献   
2.
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   
3.
International Journal of Peptide Research and Therapeutics - The original version of the article unfortunately contained a typo in co-author name.  相似文献   
4.

Background

Light-emitting diode fluorescence microscopy (LED-FM) has been shown to be more sensitive than conventional bright field microscopy using Ziehl-Neelsen (ZN) stain in detecting sputum smear positive tuberculosis in controlled laboratory conditions. In 2012, Auramine O staining based LED-FM replaced conventional ZN microscopy in 200 designated microscopy centres (DMC) of medical colleges operating in collaboration with India’s Revised National Tuberculosis Control Programme. We aimed to assess the impact of introduction of LED-FM services on sputum smear positive case detection under program conditions.

Methods

This was a before and after comparison study. In 15 randomly selected medical college DMCs, all presumptive TB patients who underwent sputum smear examination in the years 2011 (before LED-FM) and 2012 (after LED-FM) were compared. An additional 15 comparable DMCs that implemented conventional ZN sputum smear microscopy were also selected for comparison between 2011 and 2012.

Results

The proportion of presumptive TB patients (PTP)found sputum smear positive increased by 30%- from 13.6% (3432/25159) in 2011 to 17.8% (4706/26426) in 2012 (P value <0.01) in the sites that implemented LED-FM microscopy, whereas in DMCs where the ZN staining procedure is followed the proportion of sputum smear positive had remained unchanged (13.0%versus 12.6%;P value0.31).

Conclusion

Use of LED-FM significantly increased the proportion of smear positive cases among presumptive TB patients under routine program conditions in high workload laboratories. The study provides operational evidence needed to scale-up the use of LED-FM in similar settings in India and beyond.  相似文献   
5.

Objectives

There has been increased interest in the possible role of human cytomegalovirus (HCMV) in carcinogenesis during the last decade. HCMV seroprevalence was enhanced in patients with hepatocellular carcinoma (HCC) but a possible relationship between HCC and HCMV infection remained to be assessed. The aim of this work was to investigate the pro-tumor influence of HCMV on primary human hepatocytes (PHH) and HepG2 cells.

Methods

Following infection of PHH and HepG2 cells by two different strains of HCMV, we measured the production of IL-6 in culture supernatants by ELISA and the protein levels of STAT3, pSTAT3, JAK, cyclin D1, survivin, p53, p21, and Mdm2 by western Blotting in infected and uninfected cells. Cell proliferation and transformation were investigated using Ki67Ag expression measurement and soft-agar colony formation assay respectively.

Results

Infection of HepG2 cells and PHH by HCMV resulted in the production of IL-6 and the subsequent activation of the IL-6R-JAK-STAT3 pathway. HCMV increased the expression of cyclin D1 and survivin. Cell proliferation was enhanced in HepG2 and PHH infected with HCMV, despite a paradoxical overexpression of p53 and p21. More importantly, we observed the formation of colonies in soft agar seeded with PHH infected with HCMV and when we challenged the HepG2 cultures to form tumorspheres, we found that the HCMV-infected cultures formed 2.5-fold more tumorspheres than uninfected cultures.

Conclusion

HCMV activated the IL-6-JAK-STAT3 pathway in PHH and HepG2 cells, favored cellular proliferation, induced PHH transformation and enhanced HepG2 tumorsphere formation. Our observations raise the possibility that HCMV infection might be involved in the genesis of hepatocellular carcinoma.  相似文献   
6.
ObjectivePhosphorous is an essential micronutrient of plants and involved in critical biological functions. In nature, phosphorous is mostly present in immobilized inorganic mineral and in the fixed organic form including phytic acid and phosphoesteric compounds. However, the bioavailability of bound phosphorous could be enhanced by the use of phosphate solubilizing microorganisms such as bacteria and fungi. The phytases are widespread in an environment and have been isolated from different sources comprising bacteria and fungi.MethodologyIn current studies, we show the successful use of gamma rays and EMS (Ethyl Methane Sulphonate) mutagenesis for enhanced activity of phytases in a fungal strain Sporotrichum thermophile.ResultsWe report an improved strain ST2 that could produce a clear halo zone around the colony, up to 24 mm. The maximum enzymatic activity was found of 382 U/mL on pH 5.5. However, the phytase activity was improved to 387 U/ml at 45 °C. We also report that the mutants produced through EMS showed the greater potential for phytase production.ConclusionThe current study highlights the potential of EMS mutagenesis for strain improvement over physical mutagens.  相似文献   
7.
Pyrazole constitutes an important heterocyclic family covering a broad range of synthetic as well as natural products that exhibit numerous chemical, biological, agrochemical and pharmacological properties. In order to explore compounds with good fungicidal activity, a series of new pyrazole derivatives containing 5-phenyl-2-furan were designed and synthesized. In vitro and in vivo fungicidal activities were evaluated and the compound ethyl-1-(5-phenylfuran-2-carbonyl)-5-propyl-1H-pyrazole-3-carboxylate (I8) displayed significant fungicidal activity against various fungi, especially against P. infestans. The structures of the novel pyrazole derivatives were confirmed by 1H NMR, 13C NMR, MS, elemental analysis and X-ray single crystal diffraction. Further study showed that compound I8 might act on the synthesis of cell walls from morphological and ultrastructural studies by SEM and TEM. The results also revealed that compound I8 could block the nutritional transportation leading to cells senescence and death. These results suggested that the novel pyrazole derivatives proved to be promising lead compounds.  相似文献   
8.
Cell adhesion and communication are interdependent aspects of cell behavior that are critical for morphogenesis and tissue architecture. In the skin, epidermal adhesion is mediated in part by specialized cell-cell junctions known as desmosomes, which are characterized by the presence of desmosomal cadherins, known as desmogleins and desmocollins. We identified a cadherin family member, desmoglein 4, which is expressed in the suprabasal epidermis and hair follicle. The essential role of desmoglein 4 in skin was established by identifying mutations in families with inherited hypotrichosis, as well as in the lanceolate hair mouse. We also show that DSG4 is an autoantigen in pemphigus vulgaris. Characterization of the phenotype of naturally occurring mutant mice revealed disruption of desmosomal adhesion and perturbations in keratinocyte behavior. We provide evidence that desmoglein 4 is a key mediator of keratinocyte cell adhesion in the hair follicle, where it coordinates the transition from proliferation to differentiation.  相似文献   
9.
Human and animal exposure demonstrates that uranium is nephrotoxic. However, attempts to reduce it were not found suitable for clinical use. Dietary fish oil (FO) enriched in ω-3 fatty acids reduces the severity of cardiovascular and renal diseases. Present study investigates the protective effect of FO on uranyl nitrate (UN)-induced renal damage. Rats prefed with experimental diets for 15 days, given single nephrotoxic dose of UN (0.5 mg/kg body weight) intraperitoneally. After 5 d of UN treatment, serum/urine parameters, enzymes of carbohydrate metabolism, brush border membrane (BBM), oxidative stress and phosphate transport were analyzed in rat kidney. UN nephrotoxicity was characterized by increased serum creatinine and blood urea nitrogen. UN increased the activity of lactate dehydrogenase and NADP-malic enzyme whereas decreased malate, isocitrate and glucose-6-phophate dehydrogenases; glucose-6-phophatase, fructose-1, 6-bisphosphatase and BBM enzyme activities. UN caused oxidant/antioxidant imbalances as reflected by increased lipid peroxidation, activities of superoxide dismutase, glutathione peroxidase and decreased catalase activity. Feeding FO alone increased activities of enzymes of glucose metabolism, BBM, oxidative stress and Pi transport. UN-elicited alterations were prevented by FO feeding. However, corn oil had no such effects and was not similarly effective. In conclusion, FO appears to protect against UN-induced nephrotoxicity by improving energy metabolism and antioxidant defense mechanism.  相似文献   
10.
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