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891.
Renato do Prado Gomes Pedreira Eduardo Pereira Guimarães Marina Lara de Carli Evandro Monteiro de Sá Magalhães Alessandro Antônio Costa Pereira João Adolfo Costa Hanemann 《Mycopathologia》2014,177(5-6):325-329
Introduction
Paracoccidioidomycosis is a disease that is endemic to southern and southeastern Brazil, caused by the fungus Paracoccidioides brasiliensis. The most common clinical oral manifestation is the presence of multiple granulomatous ulcers with hemorrhagic dots, located mainly on the lips, palate, and buccal mucosa. However, the disease can manifest atypically as a single ulcer, mimicking oral squamous cell carcinoma (SCC) or tuberculosis.Case report
A 65-year-old male patient presented with a complaint of a single ulcerated lesion on the dorsum of the tongue; the lesion had evolved over 6 months. The diagnostic hypotheses were SCC and oral manifestation of tuberculosis. An incisional biopsy was performed, and histopathological analysis of the specimen revealed pseudoepitheliomatous hyperplasia, a granulomatous structure of epithelioid histiocytes, multinucleated giant cells, and lymphocytes in the connective tissue. Grocott staining confirmed the presence of the fungus in the lesion, and a diagnosis was made of paracoccidioidomycosis. The patient was treated with 200 mg/day of itraconazole for 12 months and now shows no signs or symptoms of recurrence of the disease.Conclusion
Correct diagnosis is essential for a successful therapeutic approach and resolution of the lesion. 相似文献892.
Madalina V. Nastase Renato V. Iozzo Liliana Schaefer 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
Small leucine-rich proteoglycans (SLRPs) are molecules that have signaling roles in a multitude of biological processes. In this respect, SLRPs play key roles in the evolution of a variety of diseases throughout the human body.Scope of Review
We will critically review current developments in the roles of SLRPs in several types of disease of the kidney and lungs. Particular emphasis will be given to the roles of decorin and biglycan, the best characterized members of the SLRP gene family.Major Conclusions
In both renal and pulmonary disorders, SLRPs are essential elements that regulate several pathophysiological processes including fibrosis, inflammation and tumor progression. Decorin has remarkable antifibrotic and antitumorigenic properties and is considered a valuable potential treatment of these diseases. Biglycan can modulate inflammatory processes in lung and renal inflammation and is a potential target in the treatment of inflammatory conditions.General Significance
SLRPs can serve as either treatment targets or as potential treatment in renal or lung disease. This article is part of a Special Issue entitled Matrix-mediated cell behaviour and properties. 相似文献893.
Rene A. Abesamis Alison L. Green Garry R. Russ Claro Renato L. Jadloc 《Reviews in Fish Biology and Fisheries》2014,24(4):1033-1063
Coral reef fishes differ in their intrinsic vulnerability to fishing and rates of population recovery after cessation of fishing. We reviewed life history-based predictions about the vulnerability of different groups of coral reef fish and examined the empirical evidence for different rates of population recovery inside no-take marine reserves to (1) determine if the empirical data agree with predictions about vulnerability and (2) show plausible scenarios of recovery within fully protected reserves and periodically-harvested fishery closures. In general, larger-bodied carnivorous reef fishes are predicted to be more vulnerable to fishing while smaller-bodied species lower in the food web (e.g., some herbivores) are predicted to be less vulnerable. However, this prediction does not always hold true because of the considerable diversity of life history strategies in reef fishes. Long-term trends in reef fish population recovery inside no-take reserves are consistent with broad predictions about vulnerability, suggesting that moderately to highly vulnerable species will require a significantly longer time (decades) to attain local carrying capacity than less vulnerable species. We recommend: (1) expanding age-based demographic studies of economically and ecologically important reef fishes to improve estimates of vulnerability; (2) long term (20–40 years), if not permanent, protection of no-take reserves to allow full population recovery and maximum biomass export; (3) strict compliance to no-take reserves to avoid considerable delays in recovery; (4) carefully controlling the timing and intensity of harvesting periodic closures to ensure long-term fishery benefits; (5) the use of periodically-harvested closures together with, rather than instead of, permanent no-take reserves. 相似文献
894.
ATP7B is a copper-transporting ATPase that plays a key role in the regulation of copper homeostasis. Mutations in the ATP7B gene are causative for Wilson’s disease, and recent reports have suggested that genetic variants are associated with susceptibility to Alzheimer’s disease. Unfortunately, it is difficult to profile experimentally novel genetic variants in the ATP7B gene, because the human protein X-ray structure is not yet entirely understood. In order to investigate ATP7B non-synonymous substitutions, we used an in silico amino acid sequence-based approach. Specifically, we analyzed 337 ATP7B non-synonymous substitutions, which included Wilson’s disease-causing mutations (DVs) and non Wilson’s disease-causing variants (NDVs), with an algorithm that estimated a combined probability (cPdel) of an amino acidic change to be deleterious for the protein function. This approach appeared to reliably indentify the probability of DVs and NDVs to be deleterious and to profile still unknown gene variants. Specifically, after analyzing ATP7B protein domains with the cPdel method, we found results in line with the predicted–modeled domains and some new suggestions. In conclusion, a functional survey of amino acid changes in the ATP7B protein is provided herein, and we suggest that this bioinformatic method can furnish information about novel ATP7B mutations. Furthermore, the same approach can be applied to other uncharacterized proteins. 相似文献
895.
Isabel Marques Paulo Almeida Renato Alves Maria Jo?o Dias Ana Godinho José B. Pereira-Leal 《PLoS computational biology》2014,10(1)
The interdisciplinary nature of bioinformatics makes it an ideal framework to develop activities enabling enquiry-based learning. We describe here the development and implementation of a pilot project to use bioinformatics-based research activities in high schools, called “Bioinformatics@school.” It includes web-based research projects that students can pursue alone or under teacher supervision and a teacher training program. The project is organized so as to enable discussion of key results between students and teachers. After successful trials in two high schools, as measured by questionnaires, interviews, and assessment of knowledge acquisition, the project is expanding by the action of the teachers involved, who are helping us develop more content and are recruiting more teachers and schools. 相似文献
896.
Leonardo Abdala Elias Renato Naville Watanabe André Fabio Kohn 《PLoS computational biology》2014,10(11)
Several models have been employed to study human postural control during upright quiet stance. Most have adopted an inverted pendulum approximation to the standing human and theoretical models to account for the neural feedback necessary to keep balance. The present study adds to the previous efforts in focusing more closely on modelling the physiological mechanisms of important elements associated with the control of human posture. This paper studies neuromuscular mechanisms behind upright stance control by means of a biologically based large-scale neuromusculoskeletal (NMS) model. It encompasses: i) conductance-based spinal neuron models (motor neurons and interneurons); ii) muscle proprioceptor models (spindle and Golgi tendon organ) providing sensory afferent feedback; iii) Hill-type muscle models of the leg plantar and dorsiflexors; and iv) an inverted pendulum model for the body biomechanics during upright stance. The motor neuron pools are driven by stochastic spike trains. Simulation results showed that the neuromechanical outputs generated by the NMS model resemble experimental data from subjects standing on a stable surface. Interesting findings were that: i) an intermittent pattern of muscle activation emerged from this posture control model for two of the leg muscles (Medial and Lateral Gastrocnemius); and ii) the Soleus muscle was mostly activated in a continuous manner. These results suggest that the spinal cord anatomy and neurophysiology (e.g., motor unit types, synaptic connectivities, ordered recruitment), along with the modulation of afferent activity, may account for the mixture of intermittent and continuous control that has been a subject of debate in recent studies on postural control. Another finding was the occurrence of the so-called “paradoxical” behaviour of muscle fibre lengths as a function of postural sway. The simulations confirmed previous conjectures that reciprocal inhibition is possibly contributing to this effect, but on the other hand showed that this effect may arise without any anticipatory neural control mechanism. 相似文献
897.
Rodrigo Juliano Oliveira Jo?o Renato Pesarini Maria José Spar?a Salles Tatiane Yumi Nakamura Kanno Ana Carolina dos Santos Louren?o Véssia da Silva Leite Ariane Fernanda da Silva Hevenilton José Matiazi Lúcia Regina Ribeiro Mário Sérgio Mantovani 《Genetics and molecular biology》2014,37(1):111-119
β-glucan is a well-known polysaccharide for its chemopreventive effect. This study aimed to evaluate the chemopreventive ability of β-glucan in somatic and germ cells through the dominant lethal and micronucleus assays, and its influence on the reproductive performance of male mice exposed to cyclophosphamide. The results indicate that β-glucan is capable of preventing changes in DNA in both germ cells and somatic ones. Changes in germ cells were evaluated by the dominant lethal assay and showed damage reduction percentages of 46.46% and 43.79% for the doses of 100 and 150 mg/kg. For the somatic changes, evaluated by micronucleus assay in peripheral blood cells in the first week of treatment, damage reduction percentages from 80.63–116.32% were found. In the fifth and sixth weeks, the percentage ranged from 10.20–52.54% and −0.95–62.35%, respectively. Besides the chemopreventive efficiency it appears that the β-glucan, when combined with cyclophosphamide, is able to improve the reproductive performance of males verified by the significant reduction in rates of post-implantation losses and reabsorption in the mating of nulliparous females with males treated with cyclophosphamide. 相似文献
898.
We studied the testate amoebae in the moss Hylocomium splendens along an altitudinal gradient from 1000 to 2200 m asl. in the south-eastern Alps of Italy in relation to micro- and macro-nutrient content of moss plants. Three mountainous areas were chosen, two of them characterised by calcareous bedrock, the third by siliceous bedrock. A total of 25 testate amoebae taxa were recorded, with a mean species richness of 9.3 per sampling plot. In a canonical correspondence analysis, 63.1% of the variation in the amoebae data was explained by moss tissue chemistry, namely by C, P, Ca, Mg, Al, Fe, and Na content and a binary site variable. We interpreted this result as an indirect effect of moss chemistry on testate amoebae through an influence on prey organisms. Although two species responded to altitude, there was no overall significant relationship between testate amoebae diversity or community structure and altitude, presumably because our sampling protocol aimed at minimizing the variability due to vegetation types and soil heterogeneity. This suggests that previous evidence of altitudinal or latitudinal effects on testate amoebae diversity may at least in part be due to a sampling bias, namely differences in soil type or moss species sampled. 相似文献
899.
Phage mediated horizontal transfer of the sopE1 gene increases enteropathogenicity of Salmonella enterica serotype Typhimurium for calves 总被引:1,自引:0,他引:1
Zhang S Santos RL Tsolis RM Mirold S Hardt WD Adams LG Bäumler AJ 《FEMS microbiology letters》2002,217(2):243-247
Anaerobic fungi are an important component of the cellulolytic ruminal microflora. Ammonia alone as N source supports growth, but amino acid mixtures are stimulatory. In order to evaluate the extent of de novo synthesis of individual amino acids in Piromyces communis and Neocallimastix frontalis, isotope enrichment in amino acids was determined during growth on (15)NH(4)Cl in different media. Most cell N (0.78 and 0.63 for P. communis and N. frontalis, respectively) and amino acid N (0.73 and 0.59) continued to be formed de novo from ammonia when 1 g l(-1) trypticase was added to the medium; this concentration approximates the peak concentration of peptides in the rumen after feeding. Higher peptide/amino acid concentrations decreased de novo synthesis. Lysine was exceptional, in that its synthesis decreased much more than other amino acids when Trypticase or amino acids were added to the medium, suggesting that lysine synthesis might limit fungal growth in the rumen. 相似文献
900.
In this study Aspergillus oryzae was utilized to remove azo dyes from aqueous solution. Physically induced in its paramorphogenic form to produce standardized
mycelial pellets, the non-autoclaved and autoclaved hyphae biomass was applied to biosorb the reactive dyes Procion Red HE7B
(PR-HE7B) and Procion Violet H3R (PV-H3R) at different pH values (2.50, 4.50, and 6.50). The best pH for biosorption was 2.50,
though the autoclaved demonstrated a higher biosorption capacity than the non-autoclaved pellets. The toxicity level was determined
using the Trimmed Spearman–Karber method with Daphnia similis in all bioassays. The calculated toxicity of PV-H3R (LC100 62.50 μg mL−1) was higher than to PR-HE7B (LC100 300.00 μg mL−1), and its results brought out that the decrease of toxicity levels to zero might be accomplished by adding small quantities
of pelletized A. oryzae to the solutions. 相似文献