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11.
Antibiotics and dyes which preclude growth of Saccharomyces cerevisiae in media containing oxidizable carbon sources arrested the growth of Candida albicans, Candida tropicalis and Candida utilis even in glucose medium. The growth in the presence of sub-inhibitory concentrations of the various antibiotics and dyes determined a reduction in the cell survival but with no accumulation of respiratory deficient mutants. Under these culture conditions, the total respiration declined leaving a residual antimycin A-resistant--hydroxamate-sensitive O2 uptake, and the amount of the respiratory cytochromes aa3 and b synthesized was reduced. SDS gel electrophoresis of soluble proteins prepared from the antibiotic-treated cells showed some bands in the MW range 92-100 K, which became faint after the cells were grown in the presence of some mitochondrial inhibitors. The ultrastructural analysis of these cells evidenced disappearance of the mitochondrial cristae and their replacement by unfolded membranes. The data obtained suggest that the petite negative trait of Candida could depend on the non-viability or on the very low viability of those cells which have lost their mitochondrial function.  相似文献   
12.
Six nervous system drugs which inhibited vegetative reproduction of S. cerevisiae arrested also mitotic division of C. utilis, C. albicans and C. tropicalis. Chlorpromazine and chlorpheniramine which proved to be the most effective, affected respiration and cytochrome biosynthesis. Electrophoretic bands with MW congruent to 100 K were faint in silver-stained electrophoregrams of proteins from cells grown in the presence of a sub-inhibitory concentration of chlorpromazine.  相似文献   
13.
Spinal muscular atrophy (SMA) refers to a group of genetic neuromuscular disorders affecting lower motor neurons causative of numerous phenotypes. To date, according to the age of onset, maximum muscular activity achieved, and life expectation four types of SMA are recognized, all caused by mutations in the SMN1 gene with SMN2 copy number influencing disease severity. Herein, we describe the case of a 31-year-old young male with normal psychomotor development who has experienced fatigue, cramps, and muscle fasciculations in the lower limbs for a period of 2 months. Based on electrophysiological and clinical findings we performed SMA genetic, clinical exome and RNA expression of candidate genes which led us to suggest SMN1-SMN2 genes [(2+0) and (0+0)] combination as possibly being implicated in the phenotype.  相似文献   
14.
Probiotics and Antimicrobial Proteins - Probiotics represent a possible strategy for controlling intestinal infections in livestock. Members of the Weissella genus are increasingly being studied...  相似文献   
15.
Abstract

Cardopatum corymbosum is a perennial hemicryptophyta species living on erosion-prone steep slopes where it forms very small, scattered communities that resist soil erosion. The aim of this study was to understand better the life cycle of this species before suggesting its use for eco-engineering purposes to stop soil erosion. We examined anatomical preparations with a light microscope, and plant anatomy was reconstructed by examining sequential cross sections of the stem cut from the shoot apex to the root collar. A single sprout above the root collar produces a rosette of leaves at the beginning of spring and a floral axis at the end of summer. The leaves and the floral axis die at the end of summer, whereas the basal portion of the new stem remains alive and forms, together with the root system, the perennial portion of this plant. This stem zone is named “transition zone” and presents leaf traces converging in the centre where they give rise to a vascular cylinder with a cambium ring dividing a secondary xylem from a secondary phloem. New buds form in the cortex of the transition zone that are quiescent and are not visible externally until the following spring when they resume growth and generate a new sprout. These buds should be considered adventitious because: (1) they form independently of leaves; and (2) their annual production could represent the plant's response to ensure its survival after the loss of the above-ground portion of the stem. Given the efficient resprouting strategy coupled with a perennial root system, C. corymbosum is a good candidate for bio-engineering applications against the soil erosion typical of steep slopes in Mediterranean climates. This species could be considered for intensive re-vegetation in order to produce a protective soil covering.  相似文献   
16.
Molecular Biology Reports - TBI is the main cause of death and disability in individuals aged 1–45 in Western countries. One of the main challenges of TBI at present is the lack of specific...  相似文献   
17.
18.
ABSTRACT

Rhythms can be observed at all levels of the biologic integration in humans. The observation that a biological or physiological variable shows a circadian rhythm can be explained by several multifactorial systems including external (exogenous), internal (endogenous) and psychobiological (lifestyle) mechanisms. Our body clock can be synchronized with the environment by external factors, called “synchronizers”, i.e. the light–dark cycle, but it is also negatively influenced by some pathological conditions or factors, called “chronodisruptors,” i.e. aging or low physical activity (PA). The desynchronization of a 24-h rhythm in a chronic manner has been recently defined “chronodisruption” or “circadian disruption.” A very large number of hormonal variables, such as adrenal and gonadal stress steroids, are governed by circadian rhythmicity. Such hormones, in normal conditions, show a peak in the first part of the day, while their typical diurnal fluctuations are totally out of sync in subjects affected by cancer or metabolic diseases, such as obesity, diabetes and metabolic syndrome. In general, a flatter slope with altered peaks in cortisol and testosterone circadian rhythms has been observed in pathological individuals. PA, specifically chronic exercise, seems to play a key role as synchronizer for the whole circadian system in such pathologies even if specific data on steroids circadian pattern are still sparse and contradictory. Recently, it has been proposed that low-intensity chronic PA could be an effective intervention to decrease morning cortisol levels in pathological subjects. The standardization of all confounding factors is needed to reach more clear evidence-based results.  相似文献   
19.
ABSTRACT

We have recently shown that rest-activity circadian rhythm significantly differed in women with Binge Eating Disorder (BED) compared to the Ctrl group. In details, patients with BED exhibited significantly reduced levels of MESOR and Amplitude with respect to the Ctrl group. In addition, in this previous study, the results of the actigraphic sleep monitoring provided no evidence of differences in sleep parameters between the two groups. We expanded the original sample obtaining a total of 28 volunteered women, 14 BED women, and 14 Ctrl. We recorded in all 28 participants a 5-day actigraphic monitoring to detect the rhythmometric parameters, interdaily stability, intradaily variability, L5, M10, and sleep parameters. During the study, BED’s women group kept an individual multidisciplinary therapy lasting five weekly days, from Monday to Friday, consisting in cognitive-behavioral therapy and nutritional program, administered in outpatient care from 8:00 a.m. at 5:00 p.m. The combination of both our previous and current study supports the conclusion that the sleep quality of the BED group is significantly better compared to Ctrl. The non-parametric indexes showed how interdaily stability, significantly correlated to sleep efficiency, was higher in BED group compared to the Ctrl group, indicating a better synchronization of rest-activity circadian rhythm. In conclusion, the maintenance of a regular lifestyle, such as imposed by the multidisciplinary therapy, is important to avoid alterations in the sleep-wake cycle, particularly in patients with eating disorders.  相似文献   
20.
Many squamous cell carcinomas (SCCs) are characterized by high levels of EGFR and by overexpression of the ΔNp63α isoform. Here, we investigated the regulation of ΔNp63α expression upon EGFR activation and the role of the EGFR–ΔNp63α axis in proliferation of SCC tumor‐initiating cells (TICs). SCC cell lines A‐431, Cal‐27, and SCC‐25 treated with EGF showed a time‐dependent increase in ΔNp63α expression at the protein and mRNA levels, which was blocked by the tyrosine kinase inhibitor (TKI) Lapatinib. RNA interference experiments suggested the role of STAT3 in regulating ΔNp63α expression downstream of EGFR. Inactivation of EGFR by the monoclonal antibody Cetuximab and RNA interference against STAT3 or ΔNp63α impaired the TICs ability to grow under non‐differentiating conditions. Radiation treatment, which triggers EGFR activation, induced ΔNp63α accumulation without affecting TICs proliferation, whereas the combination Cetuximab plus radiation significantly reduced TICs growth under non‐differentiating conditions. Together, our findings provide evidence that ΔNp63α expression is regulated by EGFR activation through STAT3 and that the EGFR–ΔNp63α axis is crucial for proliferation of TICs present in SCCs. J. Cell. Physiol. 228: 871–878, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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