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141.
Zavanela PM Crewther BT Lodo L Florindo AA Miyabara EH Aoki MS 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(3):811-817
This study examined the effects of a workplace-based resistance training intervention on different health-, fitness-, and work-related measures in untrained men (bus drivers). The subjects were recruited from a bus company and divided into a training (n = 48) and control (n = 48) groups after initial prescreening. The training group performed a 24-week resistance training program, whereas the control group maintained their normal daily activities. Each group was assessed for body composition, blood pressure (BP), pain incidence, muscular endurance, and flexibility before and after the 24-week period. Work absenteeism was also recorded during this period and after a 12-week follow-up phase. In general, no body composition changes were identified in either group. In the training group, a significant reduction in BP and pain incidence, along with improvements in muscle endurance and flexibility were seen after 24 weeks (p < 0.05). There were no changes in these parameters in the control group, and the between-group differences were all significant (p < 0.05). A reduction in worker absenteeism rate was also noted in the training (vs. control) group during both the interventional and follow-up periods (p < 0.05). In conclusion, it was found that a periodized resistance training intervention performed within the workplace improved different aspects of health and fitness in untrained men, thereby potentially providing other work-related benefits. Thus, both employers and employees may benefit from the setup, promotion, and support of a work-based physical activity program involving resistance training. 相似文献
142.
AC Intorne MV de Oliveira L de M Pereira GA de Souza Filho 《International microbiology》2012,15(1):69-78
The mechanisms of cadmium, cobalt and zinc resistance were characterized in the plant-growth-promoting bacterium Gluconacetobacter diazotrophicus PAl 5. The resistance level of the wild-type strain was evaluated through the establishment of minimum inhibitory concentrations (MIC) of the soluble compounds CdCl2·H2O, CoCl2·6H2O and ZnCl2. Gluconacetobacter diazotrophicus PAl 5 was resistant to high concentrations of Cd, Co and Zn, with MICs of 1.2, 20 and 20 mM, respectively. Screening of an insertion library from transposon EZ-Tn5 in the presence of ZnO revealed that the mutant GDP30H3 was unable to grow in the presence of the compound. This mutant was also highly sensitive to CdCl2·H2O, CoCl2·6H2O and ZnCl2. Molecular characterization established that the mutation affected the czcA gene, which encodes a protein involved in metal efflux. In silico analysis showed that czcA is a component of the czcCBARS operon together with four other genes. This work provides evidence of the high tolerance of G. diazotrophicus PAl 5 to heavy metals and that czc is a determinant for metal resistance in this bacterium. 相似文献
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The metabolic resources crucial for viral replication are provided by the host. Details of the mechanisms by which viruses interact with host metabolism, altering and recruiting high free-energy molecules for their own replication, remain unknown. Sindbis virus, the prototype of and most widespread alphavirus, causes outbreaks of arthritis in humans and serves as a model for the study of the pathogenesis of neurological diseases induced by alphaviruses in mice. In this work, respirometric analysis was used to evaluate the effects of Sindbis virus infection on mitochondrial bioenergetics of a mouse neuroblastoma cell lineage, Neuro 2a. The modulation of mitochondrial functions affected cellular ATP content and this was synchronous with Sindbis virus replication cycle and cell death. At 15 h, irrespective of effects on cell viability, viral replication induced a decrease in oxygen consumption uncoupled to ATP synthesis and a 36% decrease in maximum uncoupled respiration, which led to an increase of 30% in the fraction of oxygen consumption used for ATP synthesis. Decreased proton leak associated to complex I respiration contributed to the apparent improvement of mitochondrial function. Cellular ATP content was not affected by infection. After 24 h, mitochondria dysfunction was clearly observed as maximum uncoupled respiration reduced 65%, along with a decrease in the fraction of oxygen consumption used for ATP synthesis. Suppressed respiration driven by complexes I- and II-related substrates seemed to play a role in mitochondrial dysfunction. Despite the increase in glucose uptake and glycolytic flux, these changes were followed by a 30% decrease in ATP content and neuronal death. Taken together, mitochondrial bioenergetics is modulated during Sindbis virus infection in such a way as to favor ATP synthesis required to support active viral replication. These early changes in metabolism of Neuro 2a cells may form the molecular basis of neuronal dysfunction and Sindbis virus-induced encephalitis. 相似文献
146.
Soler N Plomer M Fagoaga C Moreno P Navarro L Flores R Peña L 《Plant biotechnology journal》2012,10(5):597-608
Citrus tristeza virus (CTV), the causal agent of the most devastating viral disease of citrus, has evolved three silencing suppressor proteins acting at intra- (p23 and p20) and/or intercellular level (p20 and p25) to overcome host antiviral defence. Previously, we showed that Mexican lime transformed with an intron-hairpin construct including part of the gene p23 and the adjacent 3' untranslated region displays partial resistance to CTV, with a fraction of the propagations from some transgenic lines remaining uninfected. Here, we transformed Mexican lime with an intron-hairpin vector carrying full-length, untranslatable versions of the genes p25, p20 and p23 from CTV strain T36 to silence the expression of these critical genes in CTV-infected cells. Three transgenic lines presented complete resistance to viral infection, with all their propagations remaining symptomless and virus-free after graft inoculation with CTV-T36, either in the nontransgenic rootstock or in the transgenic scion. Accumulation of transgene-derived siRNAs was necessary but not sufficient for CTV resistance. Inoculation with a divergent CTV strain led to partially breaking the resistance, thus showing the role of sequence identity in the underlying mechanism. Our results are a step forward to developing transgenic resistance to CTV and also show that targeting simultaneously by RNA interference (RNAi) the three viral silencing suppressors appears critical for this purpose, although the involvement of concurrent RNAi mechanisms cannot be excluded. 相似文献
147.
LL Matos AB Del Giglio CO Matsubayashi ML Farah A Del Giglio MA Pinhal 《Diagnostic pathology》2012,7(1):97
ABSTRACT: BACKGROUND: To distinguish between malignant and benign lesions of the thyroid gland histological demonstration is often required since the fine-needle aspiration biopsy method applied pre-operatively has some limitations. In an attempt to improve diagnostic accuracy, markers using immunocytochemistry and immunohistochemistry techniques have been studied, mainly cytokeratin-19 (CK-19), galectin-3 (Gal-3) and Hector Battifora mesothelial-1 (HBME-1). However, current results remain controversial. The aim of the present article was to establish the diagnostic accuracy of CK-19, Gal-3 and HBME-1 markers, as well as their associations, in the differentiation of malignant and benign thyroid lesions. METHODS: A systematic review of published articles on MEDLINE and The Cochrane Library was performed. After establishing inclusion and exclusion criteria, 66 articles were selected. The technique of meta-analysis of diagnostic accuracy was employed and global values of sensitivity, specificity, area under the summary ROC curve, and diagnostic odds ratio (dOR) were calculated. RESULTS: For the immunohistochemistry technique, the positivity of CK-19 for the diagnosis of malignant thyroid lesions demonstrated global sensitivity of 81% and specificity of 73%; for Gal-3, sensitivity of 82% and specificity of 81%; and for HBME-1, sensitivity of 77% and specificity of 83%. The association of the three markers determined sensitivity of 85%, specificity of 97%, and diagnostic odds ratio of 95.1. Similar results were also found for the immunocytochemistry assay. CONCLUSION: This meta-analysis demonstrated that the three immunomarkers studied are accurate in pre- and postoperative diagnosis of benign and malignant thyroid lesions. Nevertheless, the search for other molecular markers must continue in order to enhance this diagnostic accuracy since the results found still show a persistency of false-negative and false-positive tests.Virtual slidesHttp://www.diagnosticpathology.diagnomx.eu/vs/3436263067345159. 相似文献
148.
The hypothalamus-pituitary-adrenal axis (HPA) participates in mediating the response to stressful stimuli. Within the HPA, neurons in the medial parvocellular region of paraventricular nucleus (PVN) of the hypothalamus integrate excitatory and inhibitory signals triggering secretion of corticotropin-releasing hormone (CRH), the main secretagogue of adrenocorticotropic hormone (ACTH). Stressful situations alter CRH secretion as well as other hormones, including prolactin and oxytocin. Most inputs to the PVN are of local origin, half of which are GABAergic neurons, and both GABA-A and GABA-B receptors are present in the PVN. The objective of the present study was to investigate the role of GABA-A and GABA-B receptors in the PVN's control of stress-induced corticosterone, oxytocin and prolactin secretion. Rats were microinjected with saline or different doses (0.5, 5 and 50 pmol) of GABA-A (bicuculine) or GABA-B (phaclofen) antagonists in the PVN. Ten minutes later, they were subjected to a stressor (ether inhalation) and blood samples were collected 30 min before and 10, 30, 60, 90 and 120 min after the stressful stimulus to measure hormone levels by radioimmunoassay. Our results indicate that GABA acts in the PVN to inhibit stress-induced corticosterone secretion via both its receptor subtypes, especially GABA-B. In contrast, GABA in the PVN stimulates oxytocin secretion through GABA-B receptors and does not alter prolactin secretion. 相似文献
149.
Costa NJ Bombardieri CR Kuribayashi JS de Camargo MM Andrade LH Kagohara E Espósito BP 《化学与生物多样性》2008,5(10):2156-2159
It is shown that metal complexes of the biodegradable ligand ethylenediaminedisuccinic acid (edds) present antimicrobial activity towards fungi and bacteria. [Cd(edds)], in particular, is more toxic than free Cd2+ to Aspergillus niger, behaving as a 'Trojan Horse' in the facilitated delivery of the toxic metal into the fungus. 相似文献
150.
Luduvico I Couri MR dos Santos LJ Prado MA Gil RP Alves RB 《Carbohydrate research》2008,343(3):536-540
Several novel N-1, N-2, and S-5 tetrazole and 1,3,4-oxadiazole derivatives of alpha,alpha-trehalose disubstituted at C-6,6', with potential synthetic and pharmacological interest were prepared from commercial tetrazoles and 1,3,4-oxadiazoles in reaction with hexa-O-benzyl-6,6'-di-O-triflyl-alpha,alpha-trehalose. 相似文献