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1.
A sucrose density gradient analysis of3H-uridine pulse-labelled RNA from the first postirradiation mitotic cycle ofPhysarum polycephalum shows that all the density classes of RNA synthesized during this period are resistant to the peptide-antibiotic, actinomycin D. In fact, the synthesis is found to be greater in the presence of the drug. The heterogenously sedimenting synthetic activity here may represent a single species of RNA and its precursors or more than one kind of RNA. Further characterization of this RNA is meaningful in view of the actinomycin insensitivity of the postirradiation mitotic cycle itself to this antibiotic.  相似文献   
2.
Acarbose blocks the digestion of complex carbohydrates, and the NIA Intervention Testing Program (ITP) found that it improved survival when fed to mice. Yet, we do not know if lifespan extension was caused by its effect on metabolism with regard to the soma or cancer suppression. Cancer caused death for ~80% of ITP mice. The ITP found rapamycin, an inhibitor to the pro‐growth mTORC1 (mechanistic target of rapamycin complex 1) pathway, improved survival and it suppressed tumors in Apc+/Min mice providing a plausible rationale to ask if acarbose had a similar effect. Apc+/Min is a mouse model prone to intestinal polyposis and a mimic of familial adenomatous polyposis in people. Polyp‐associated anemia contributed to their death. To address this knowledge gap, we fed two doses of acarbose to Apc+/Min mice. Acarbose improved median survival at both doses. A cross‐sectional analysis was performed next. At both doses, ACA fed mice exhibited reduced intestinal crypt depth, weight loss despite increased food consumption and reduced postprandial blood glucose and plasma insulin, indicative of improved insulin sensitivity. Dose‐independent and dose‐dependent compensatory liver responses were observed for AMPK and mTORC1 activities, respectively. Only mice fed the high dose diet exhibited reductions in tumor number with higher hematocrits. Because low‐dose acarbose improved lifespan but failed to reduced tumors, its effects seem to be independent of cancer. These data implicate the importance of improved carbohydrate metabolism on survival.  相似文献   
3.
Urinary tract infections are second most important diseases worldwide due to the increased amount of antibiotic resistant microbes. Among the Gram negative bacteria, P. mirabilis is the dominant biofilm producer in urinary tract infections next to E. coli. Biofilm is a process that produced self-matrix of more virulence pathogens on colloidal surfaces. Based on the above fact, this study was concentrated to inhibit the P. mirabilis biofilm formation by various in-vitro experiments. In the current study, the anti-biofilm effect of essential oils was recovered from the medicinal plant of Solanum nigrum, and confirmed the available essential oils by liquid chromatography-mass spectroscopy analysis. The excellent anti-microbial activity and minimum biofilm inhibition concentration of the essential oils against P. mirabilis was indicated at 200 µg/mL. The absence of viability and altered exopolysaccharide structure of treated cells were showed by biofilm metabolic assay and phenol–sulphuric acid method. The fluorescence differentiation of P. mirabilis treated cells was showed with more damages by confocal laser scanning electron microscope. Further, more morphological changes of essential oils treated cells were differentiated from normal cells by scanning electron microscope. Altogether, the results were reported that the S. nigrum essential oils have anti-biofilm ability.  相似文献   
4.
Applied Entomology and Zoology - The efficacy of mating disruption with Isonet®-T at the rate of 30, 45 or 60 g a.i. ha –1 of sex pheromone to control Tuta absoluta (Meyrick)...  相似文献   
5.
Chromosomal abnormalities are seen in nearly 1% of live born infants. We report a 5-year-old boy with the clinical features of Down syndrome, which is the most common human aneuploidy. Cytogenetic analysis showed a mosaicism for a double aneuploidy, Down syndrome and XYY. The karyotype was 47, XY,+21[19]/48, XYY,+21[6]. ish XYY (DXZ1 × 1, DYZ1 × 2). Mosaic double aneuploidies are very rare and features of only one of the aneuploidies may predominate in childhood. Cytogenetic analysis is recommended even if the typical features of a recognized aneuploidy are present so that any associated abnormality may be detected. This will enable early intervention to provide the adequate supportive care and management.  相似文献   
6.
Radioligand therapies have opened new treatment avenues for cancer patients. They offer precise tumor targeting with a favorable efficacy-to-toxicity profile. Specifically, the kidneys, once regarded as the critical organ for radiation toxicity, also show excellent tolerance to radiation doses as high as 50–60 Gy in selected cases. However, the number of nephrons that form the structural and functional units of the kidney is determined before birth and is fixed. Thus, loss of nephrons secondary to any injury may lead to an irreversible decline in renal function over time. Our primary understanding of radiation-induced nephropathy is derived from the effects of external beam radiation on the renal tissue. With the growing adoption of radionuclide therapies, considerable evidence has been gained with regard to the occurrence of renal toxicity and its associated risk factors. In this review, we discuss the radionuclide therapies associated with the risk of nephrotoxicity, the present understanding of the factors and mechanisms that contribute to renal injury, and the current and potential methods for preventing, identifying, and managing nephrotoxicity, specifically acute onset nephropathies.  相似文献   
7.
2-Amino-4-azaindoles have been identified as a structurally novel class of BK(Ca) channel openers. Their synthesis from 2-chloro-3-nitropyridine is described together with their in vitro properties assessed by 86Rb(+) efflux and whole-cell patch-clamp assays using HEK293 cells stably transfected with the BK(Ca) alpha subunit. In vitro functional characterization of BK(Ca) channel opening activity was also assessed by measurement of relaxation of smooth muscle tissue strips obtained from Landrace pig bladders. The preliminary SAR data indicate the importance of steric bulk around the 2-amino substituent.  相似文献   
8.
PurposeAssess prevalence of myopia and identify associated risk factors in urban school children.MethodsThis was a cross-sectional study screening children for sub-normal vision and refractive errors in Delhi. Vision was tested by trained health workers using ETDRS charts. Risk factor questionnaire was filled for children with vision <6/9.5, wearing spectacles and for a subset (10%) of randomly selected children with normal vision. All children with vision <6/9.5 underwent cycloplegic refraction. The prevalence of myopia <-0.5 diopters was assessed. Association of risk factors and prevalence of myopia was analyzed for children with myopia and randomly selected non myopic children and adjusted odds ratio values for all risk factors were estimated.ResultsA total number of 9884 children were screened with mean age of 11.6 + 2.2 years and 66.8% boys. Prevalence of myopia was 13.1% with only 320 children (24.7%) wearing appropriate spectacles. Mean myopic spherical error was -1.86 + 1.4 diopters. Prevalence of myopia was higher in private schools compared to government schools (p<0.001), in girls vs. boys (p = 0.004) and among older (> 11 years) children (p<0.001). There was a positive association of myopia with studying in private schools vs. government schools (p<0.001), positive family history (p< 0.001) and higher socio-economic status (p = 0.037). Positive association of presence of myopia was observed with children studying/reading > 5 hours per day (p < 0.001), watching television > 2 hours / day (p < 0.001) and with playing computer/video/mobile games (p < 0.001). An inverse association with outdoor activities/playing was observed with children playing > 2 hours in a day.ConclusionMyopia is a major health problem in Indian school children. It is important to identify modifiable risk factors associated with its development and try to develop cost effective intervention strategies.  相似文献   
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10.
Classical activation of macrophages (caMph or M1) is crucial for host protection against Mycobacterium tuberculosis (Mtb) infection. Evidence suggests that IL-4/IL-13 alternatively activated macrophages (aaMph or M2) are exploited by Mtb to divert microbicidal functions of caMph. To define the functions of M2 macrophages during tuberculosis (TB), we infected mice deficient for IL-4 receptor α on macrophages (LysMcreIL-4Rα-/lox) with Mtb. We show that absence of IL-4Rα on macrophages does not play a major role during infection with Mtb H37Rv, or the clinical Beijing strain HN878. This was demonstrated by similar mortality, bacterial burden, histopathology and T cell proliferation between infected wild-type (WT) and LysMcreIL-4Rα-/lox mice. Interestingly, we observed no differences in the lung expression of inducible nitric oxide synthase (iNOS) and Arginase 1 (Arg1), well-established markers for M1/M2 macrophages among the Mtb-infected groups. Kinetic expression studies of IL-4/IL-13 activated bone marrow-derived macrophages (BMDM) infected with HN878, followed by gene set enrichment analysis, revealed that the MyD88 and IL-6, IL-10, G-CSF pathways are significantly enriched, but not the IL-4Rα driven pathway. Together, these results suggest that IL-4Rα-macrophages do not play a central role in TB disease progression.  相似文献   
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