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51.
Fred Bernardes Filho Jaci Maria Santana Regina Coeli Palma de Almeida Glauber Voltan Natlia Aparecida de Paula Marcel Nani Leite Claudia Maria Lincoln Silva Camila Tormena Lean Basoli Joelma Menezes Moises Batista da Silva John Stewart Spencer Wilson Marques Jr Norma Tiraboschi Foss Marco Andrey Cipriani Frade 《PLoS neglected tropical diseases》2020,14(12)
BackgroundThis study evaluates an active search strategy for leprosy diagnosis based on responses to a Leprosy Suspicion Questionnaire (LSQ), and analyzing the clinical, immunoepidemiological and follow-up aspects for individuals living in a prison population.MethodsA cross-sectional study based on a questionnaire posing 14 questions about leprosy symptoms and signs that was distributed to 1,400 prisoners. This was followed by dermatoneurological examination, anti-PGL-I serology and RLEP-PCR. Those without leprosy were placed in the Non-leprosy Group (NLG, n = 1,216) and those diagnosed with clinical symptoms of leprosy were placed in the Leprosy Group (LG, n = 34).FindingsIn total, 896 LSQ were returned (64%), and 187 (20.9%) of the responses were deemed as positive for signs/symptoms, answering 2.7 questions on average. Clinically, 1,250 (89.3%) of the prisoners were evaluated resulting in the diagnosis of 34 new cases (LG), based on well-accepted clinical signs and symptoms, a new case detection rate of 2.7% within this population, while the NLG were comprised of 1,216 individuals. The confinement time medians were 39 months in the LG while it was 36 months in the NLG (p>0.05). The 31 leprosy cases who responded to the questionnaire (LSQ+) had an average of 1.5 responses. The symptoms “anesthetized skin area” and “pain in nerves” were most commonly mentioned in the LG while “tingling, numbness in the hands/feet”, “sensation of pricks and needles”, “pain in nerves” and “spots on the skin” responses were found in more than 30% of questionnaires in the NLG. Clinically, 88.2% had dysesthetic macular skin lesions and 97.1% presented some peripheral nerve impairment, 71.9% with some degree of disability. All cases were multibacillary, confirming a late diagnosis. Anti-PGL-I results in the LG were higher than in the NLG (p<0.0001), while the RLEP-PCR was positive in 11.8% of the patients.InterpretationOur findings within the penitentiary demonstrated a hidden prevalence of leprosy, although the individuals diagnosed were likely infected while living in their former communities and not as a result of exposure in the prison. The LSQ proved to be an important screening tool to help identify leprosy cases in prisons. 相似文献
52.
Euskirchen P Skaftnesmo KO Huszthy PC Brekkå N Bjerkvig R Jacobs AH Miletic H 《Experimental cell research》2011,(20):2864-2873
The cell fate determinant NUMB orchestrates asymmetric cell division in flies and mammals and has lately been suggested to have a tumor suppressor function in breast and lung cancer. Here, we studied NUMB in the context of malignant gliomas. We used ectopic expression of NUMB in order to inhibit proliferation and induce differentiation in glioma cells by alteration of Notch, Hedgehog and p53 signaling. We found that NUMB is consistently expressed in glioma biopsies with predominance of NUMB2/4 isoforms as determined by isoform-specific real-time PCR and Western blotting. Upon lentiviral overexpression, in vitro proliferation rate and the grade of differentiation as assessed by morphology and expression of neural and glial markers remained unchanged. Orthotopic xenografts of NUMB-transduced human U87 glioma cells could be established in nude rats without impairing engraftment or causing significant changes in morphology based on magnetic resonance imaging (MRI). The previously reported alteration of Hedgehog and p53 signaling by NUMB could not be recapitulated in glioma cells. We thus show that in experimental gliomas, NUMB overexpression most likely does not exert a tumor suppressor function such as seen in epithelial cancers. 相似文献
53.
Larsson M Norrander J Gräslund S Brundell E Linck R Ståhl S Höög C 《European journal of cell biology》2000,79(10):718-725
Tektins comprise a family of filament-forming proteins that are known to be coassembled with tubulins to form ciliary and flagellar microtubules. Recently we described the sequence of the first mammalian tektin protein, Tekt1 (from mouse testis), which is most homologous with sea urchin tektin C. We have now investigated the temporal and spatial expression of Tekt1 during mouse male germ cell development. By in situ hybridization analysis TEKT1 RNA expression is detected in spermatocytes and in round spermatids in the mouse testis. Immunofluorescence microscopy analysis with anti-Tekt1 antibodies showed no distinct labeling of any subcellular structure in spermatocytes, whereas in round spermatids anti-Tekt1 antibodies co-localize with anti-ANA antibodies to the centrosome. At a later stage, elongating spermatids display a larger area of anti-Tektl staining at their caudal ends; as spermiogenesis proceeds, the anti-Tekt1 staining disappears. Together with other evidence, these results provide the first intraspecies evidence that Tekt1 is transiently associated with the centrosome, and indicates that Tekt1 is one of several tektins to participate in the nucleation of the flagellar axoneme of mature spermatozoa, perhaps being required to assemble the basal body. 相似文献
54.
Frostegård J 《Arthritis research & therapy》2011,13(3):225
During recent years atherosclerosis, the major cause of cardiovascular disease (CVD), has been recognised as a chronic inflammatory
condition in which rupture of atherosclerotic lesions appears to play a major role. The risk of CVD is raised in many rheumatic
diseases. This risk is high in systemic lupus erythematosus - as much as a 50-times increase among middle-aged women has been
reported. Studies on CVD and atherosclerosis in rheumatic disease could thus provide interesting information about CVD and
atherosclerosis in addition to being an important clinical problem. A combination of traditional and nontraditional risk factors
accounts for the increased risk of CVD and atherosclerosis in rheumatic disease. One interesting possibility is that atherosclerotic
lesions in rheumatic disease are more prone to rupture than normal atherosclerotic lesions. It is also likely that increased
risk of thrombosis may play an important role, not least in systemic lupus erythematosus. Further, it is not clear whether
an increased risk of CVD is a general feature of rheumatic disease, or whether this only occurs among subgroups of patients.
It should be emphasised that there is an apparent lack of treatment studies where CVD in rheumatic disease is the end point.
Control of disease activity and of traditional risk factors, however, appears to be well founded in relation to CVD in rheumatic
disease. Further studies are needed to determine the exact role of lipid-lowering drugs as statins. Hopefully novel therapies
can be developed that target the causes of the inflammation in atherosclerotic lesions both in rheumatic patients and in the
general population. 相似文献
55.
Enzymatic conversion of structural polysaccharides in plant biomass is a key issue in the development of second generation ('lignocellulosic') bioethanol. The efficiency of this process depends in part on the ability of enzymes to disrupt crystalline polysaccharides, thus gaining access to single polymer chains. Recently, new insights into how enzymes accomplish this have been obtained from studies on enzymatic conversion of chitin. First, chitinolytic microorganisms were shown to produce non-hydrolytic accessory proteins that increase enzyme efficiency. Second, it was shown that a processive mechanism, which is generally considered favorable because it improves substrate accessibility, might in fact slow down enzymes. These findings suggest new focal points for the development of enzyme technology for depolymerizing recalcitrant polysaccharide biomass. Improving substrate accessibility should be a key issue because this might reduce the need for using processive enzymes, which are intrinsically slow and abundantly present in current commercial enzyme preparations for biomass conversion. Furthermore, carefully selected substrate-disrupting accessory proteins or domains might provide novel tools to improve substrate accessibility and thus contribute to more efficient enzymatic processes. 相似文献
56.
CD8 is expressed on cytotoxic T-cells where it functions as a co-receptor for the TCR by binding to MHC class I proteins that present peptides on the cell surface. In this study we describe the cloning and sequencing of full length cDNAs encoding CD8alpha and CD8beta from Atlantic halibut (Hippoglossus hippoglossus L.) and subsequent isolation and characterization of the CD8alpha and CD8beta genes. The predicted halibut CD8alpha and CD8beta proteins are similar to those of mammals and other fish. Real time RT-PCR revealed that the highest levels of CD8 mRNA were found in the thymus, while some expression was also seen in the spleen, the gills, and the anterior and posterior kidney. In situ hybridization confirmed that the halibut thymus contained numerous CD8alpha and CD8beta expressing cells, while the anterior kidney had no CD8alpha positive cells but only a few CD8beta expressing cells. Only moderate changes in CD8 mRNA expression in other organs during either nodavirus or Vibrio anguillarum infection were observed. Both CD8alpha and CD8beta were significantly (P<0.05) down-regulated in spleen at 48h compared to their levels at 12h post-infection with nodavirus and V. anguillarum. 相似文献
57.
Fizza Arain Lars Gullestad Ståle Nymo John Kjekshus John G. Cleland Annika Michelsen 《Biomarkers》2017,22(3-4):261-267
Context and objective: To evaluate if YKL-40 can provide prognostic information in patients with ischemic heart failure (HF) and identify patients who may benefit from statin therapy.
Materials and methods: The association between serum YKL-40 and predefined outcome was evaluated in 1344 HF patients assigned to rosuvastatin or placebo.
Results: YKL-40 was not associated with outcome in adjusted analysis. In YKL-40 tertile 1, an effect on the primary outcome (HR 0.50, p?=?0.006) and CV death (HR 0.54, p?=?0.040) was seen by rosuvastatin in adjusted analysis.
Conclusions: A beneficial modification of outcome was observed with statin therapy in patients with low YKL-40 levels. 相似文献
58.
Considerable knowledge exists about the effect of aluminium (Al) on root vitality, but whether elevated levels of Al affect
soil microorganisms is largely unknown. We thus compared soils from Al-treated and control plots of a field experiment with
respect to microbial and chemical parameters, as well as root growth and vitality. The field experiment was established in
a 50-year-old Norway spruce (Picea abies L.) stand where no Al or low concentrations of Al had been added every 7–10 days during the growth season for 7 years. Analysis
of soil solutions collected using zero tension lysimeters and porous suction cups showed that Al treatment lead to increased
concentrations of Al, Ca and Mg and lower pH and [Ca + Mg + K/Al] molar ratio. Corresponding soil analyses showed that soil
pH remained unaffected (pH 3.8), that exchangeable Al increased, while exchangeable Ca and Mg decreased due to the Al treatment.
Root in-growth into cores placed in the upper 20 cm of the soil during three growth seasons was not affected by Al additions,
neither was nutrient concentration or mortality of these roots. The biomass of some taxonomic groups of soil microorganisms,
analyzed using specific membrane components (phospholipid fatty acids; PLFAs), was clearly affected by the imposed Al treatment,
both in the organic soil horizon and in the underlying mineral soil. Microbial community structure in both horizons was also
clearly modified by the Al treatment. Shifts in PLFA trans/cis ratios indicative of short term physiological stress were not observed. Yet, aluminium stress was indicated both by changes
in community structure and in ratios of single PLFAs for treated/untreated plots. Thus, soil microorganisms were more sensitive
indicators of subtle chemical changes in soil than chemical composition and vitality of roots. 相似文献
59.
Thermoperiodic stem elongation involves transcriptional regulation of gibberellin deactivation in pea 总被引:3,自引:0,他引:3 下载免费PDF全文
The physiological basis of thermoperiodic stem elongation is as yet poorly understood. Thermoperiodic control of gibberellin (GA) metabolism has been suggested as an underlying mechanism. We have investigated the influence of different day and night temperature combinations on GA levels, and diurnal steady-state expression of genes involved in GA biosynthesis (LS, LH, NA, PSGA20ox1, and PsGA3ox1) and GA deactivation (PsGA2ox1 and PsGA2ox2), and related this to diurnal stem elongation in pea (Pisum sativum L. cv Torsdag). The plants were grown under a 12-h light period with an average temperature of 17 degrees C. A day temperature/night temperature combination of 13 degrees C/21 degrees C reduced stem elongation after 12 d by 30% as compared to 21 degrees C/13 degrees C. This was correlated with a 55% reduction of GA1. Although plant height correlated with GA1 content, there was no correlation between diurnal growth rhythms and GA1 content. NA, PsGA20ox1, and PsGA2ox2 showed diurnal rhythms of expression. PsGA2ox2 was up-regulated in 13 degrees C/21 degrees C (compared to 21 degrees C/13 degrees C), at certain time points, by up to 19-fold. Relative to PsGA2ox2, the expression of LS, LH, NA, PSGA20ox1, PsGA3ox1, and PsGA2ox1 was not or only slightly affected by the different temperature treatments. The sln mutant having a nonfunctional PsGA2ox1 gene product showed the same relative stem elongation response to temperature as the wild type. This supports the importance of PsGA2ox2 in mediating thermoperiodic stem elongation responses in pea. We present evidence for an important role of GA catabolism in thermoperiodic effect on stem elongation and conclude that PsGA2ox2 is the main mediator of this effect in pea. 相似文献
60.
Pocanschi CL Apell HJ Puntervoll P Høgh B Jensen HB Welte W Kleinschmidt JH 《Journal of molecular biology》2006,355(3):548-561
Membrane protein insertion and folding was studied for the major outer membrane protein of Fusobacterium nucleatum (FomA), which is a voltage-dependent general diffusion porin. The transmembrane domain of FomA forms a beta-barrel that is predicted to consist of 14 beta-strands. Here, unfolded FomA is shown to insert and fold spontaneously and quantitatively into phospholipid bilayers upon dilution of the denaturant urea, which was shown previously only for outer membrane protein A (OmpA) of Escherichia coli. Folding of FomA is demonstrated by circular dichroism and fluorescence spectroscopy, by SDS-polyacrylamide gel electrophoresis, and by single-channel recordings. Refolded FomA had a single-channel conductance of 1.1 nS at 1 M KCl, in agreement with the conductance of FomA isolated from membranes in native form. In contrast to OmpA, which forms a smaller eight-stranded beta-barrel domain, folding kinetics of the larger FomA were slower and provided evidence for parallel folding pathways of FomA into lipid bilayers. Two pathways were observed independent of membrane thickness with two different lipid bilayers, which were either composed of dicapryl phosphatidylcholine or dioleoyl phosphatidylcholine. This is the first observation of parallel membrane insertion and folding pathways of a beta-barrel membrane protein from an unfolded state in urea into lipid bilayers. The kinetics of both folding pathways depended on the chain length of the lipid and on temperature with estimated activation energies of 19 kJ/mol (dicapryl phosphatidylcholine) and 70 kJ/mol (dioleoyl phosphatidylcholine) for the faster pathways. 相似文献