2,066 research outputs found
Selection On Different Genes With Equivalent Functions: The Convergence Story Told By Hox Genes Along The Evolution Of Aquatic Mammalian Lineages
Coordenação de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq)Convergent evolution has been a challenging topic for decades, being cetaceans, pinnipeds and sirenians textbook examples of three independent origins of equivalent phenotypes. These mammalian lineages acquired similar anatomical features correlated to an aquatic life, and remarkably differ from their terrestrial counterparts. Whether their molecular evolutionary history also involved similar genetic mechanisms underlying such morphological convergence nevertheless remained unknown. To test for the existence of convergent molecular signatures, we studied the molecular evolution of Hox genes in these three aquatic mammalian lineages, comparing their patterns to terrestrial mammals. Hox genes are transcription factors that play a pivotal role in specifying embryonic regional identity of nearly any bilateral animal, and are recognized major agents for diversification of body plans. Results: We detected few signatures of positive selection on Hox genes across the three aquatic mammalian lineages and verified that purifying selection prevails in these sequences, as expected for pleiotropic genes. Genes found as being positively selected differ across the aquatic mammalian lineages, but we identified a substantial overlap of their developmental functions. Such pattern likely resides on the duplication history of Hox genes, which probably provided different possible evolutionary routes for achieving the same phenotypic solution. Conclusions: Our results indicate that convergence occurred at a functional level of Hox genes along three independent origins of aquatic mammals. This conclusion reinforces the idea that different changes in developmental genes may lead to similar phenotypes, probably due to the redundancy provided by the participation of Hox paralogous genes in several developmental functions.16Ciencia sem Fronteiras - Atracao de Jovens Talentos CAPES [054/2012]FAPESP-Brazil [2010/52316-3]CNPq-Brazil [563232/2010-2]Coordenação de Aperfeiçoamento de Pessoal de NÃvel Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Conselho Nacional de Desenvolvimento CientÃfico e Tecnológico (CNPq
From Clinical Presentation to the Outcome: the Natural History of PML in a Portuguese Population of HIV Infected Patients
Background
Progressive multifocal leukoencephalopathy (PML) is a demyelinating disease of the central nervous system, associated with immunosuppression states. As there are only some non-published documents concerning PML in HIV infected patients in Portugal, we pretend to characterize natural history of PML infection in a population of HIV patients.
Methods
We retrospectively reviewed, from 1992 to 2009, PML cases in a population of 724 HIV infected patients followed in our institution. Clinical, biological, imagery features and outcomes were characterized.
Results
Twenty-five (3.45%) patients were identified as having PML. The mean time between HIV and PML diagnosis was 20.4 months. PML was the presentation of HIV infection in 40% of the patients, and 92% had CD4 T cell count lower than 200/mm3. Paresis was the most common clinical presentation. No specific characteristics were found in cerebrospinal fluid and JCV DNA was positive in 3 of 7 patients. MRI revealed characteristic findings. Combined antiretroviral therapy was started or changed in 96% of the patients. Neurological condition got worse in 12 patients. From the 14 deaths, 5 were directly attributed to PML progression. Follow-up was lost in 8 patients.
Conclusions
PML was the presentation of HIV infection in more than 1/3 of patients, frequently associated with advanced immunocompromise. MRI sensitivity to PML is high, and JCV DNA determination in CSF was not revealed to be sensible. PML diagnosis should be taken into account in HIV patients presenting any neurological symptoms, and HIV infection should be suspected when radiological findings suggest PML lesions even in previously healthy individuals
Reference values for lung function tests: III. Carbon monoxide diffusing capacity (transfer factor)
Carbon monoxide diffusing capacity (DLCO) or transfer factor (TLCO) is a particularly useful test of the appropriateness of gas exchange across the lung alveolocapillary membrane. With the purpose of establishing predictive equations for DLCO using a non-smoking sample of the adult Brazilian population, we prospectively evaluated 100 subjects (50 males and 50 females aged 20 to 80 years), randomly selected from more than 8,000 individuals. Gender-specific linear prediction equations were developed by multiple regression analysis with single breath (SB) absolute and volume-corrected (VA) DLCO values as dependent variables. In the prediction equations, age (years) and height (cm) had opposite effects on DLCOSB (ml min-1 mmHg-1), independent of gender (-0.13 (age) + 0.32 (height) - 13.07 in males and -0.075 (age) + 0.18 (height) + 0.20 in females). On the other hand, height had a positive effect on DLCOSB but a negative one on DLCOSB/VA (P0.05). Our results therefore provide an original frame of reference for either DLCOSB or DLCOSB/VA in Brazilian males and females aged 20 to 80 years, obtained from the standardized single-breath technique.University of LondonUniversidade Federal de São Paulo (UNIFESP)UNIFESPSciEL
Estudo dos agentes causais de diarreia em crianças menores de 5 anos no Hospital Geral do Bengo
A diarreia pode ser causada por vÃrus, parasitas e bactérias e constitui uma das principais causas de doença e morte em crianças menores de cinco anos em Angola. O presente estude assume como principal objectivo identificar os agentes patogénicos causadores de diarreia em crianças admitidas no Hospital Geral do Bengo
Estudo dos agentes causais de diarreia em crianças menores de 5 anos no Hospital Geral do Bengo
A diarreia pode ser causada por vÃrus, parasitas e bactérias e constitui uma das principais causas de doença e morte em crianças menores de cinco anos em Angola. O presente estude assume como principal objectivo identificar os agentes patogénicos causadores de diarreia em crianças admitidas no Hospital Geral do Bengo
Assis Reis: arquitetura, regionalismo e modernidade
O estudo de certas expressões arquitetônicas no Brasil, cognominadas de regionais, constituiu o propósito do presente texto. Essas expressões se destacaram como uma alternativa aos ditames do movimento moderno, a partir de 1960 e após BrasÃlia, como um reflexo do trabalho da segunda geração dos modernistas brasileiros. Tomou-se como parâmetro a produção do arquiteto Assis Reis, na Bahia, entre os anos de 1952 e 1992, perÃodo destacado pelo caráter homogêneo da obra e marcante pelas as suas referências locais. É um método projetual que considera a suplantação do movimento moderno, a partir dos vÃnculos locais e dos reclames por uma pluralidade na arquitetura brasileira. Dessa forma, avalia em que medida é possÃvel relacionar-se arquitetura, regionalismo e modernidade, um experimento que ora é apresentado de forma resumida
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4-Phenylbutyrate Attenuates the ER Stress Response and Cyclic AMP Accumulation in DYT1 Dystonia Cell Models
Dystonia is a neurological disorder in which sustained muscle contractions induce twisting and repetitive movements or abnormal posturing. DYT1 early-onset primary dystonia is the most common form of hereditary dystonia and is caused by deletion of a glutamic acid residue (302/303) near the carboxyl-terminus of encoded torsinA. TorsinA is localized primarily within the contiguous lumen of the endoplasmic reticulum (ER) and nuclear envelope (NE), and is hypothesized to function as a molecular chaperone and an important regulator of the ER stress-signaling pathway, but how the mutation in torsinA causes disease remains unclear. Multiple lines of evidence suggest that the clinical symptoms of dystonia result from abnormalities in dopamine (DA) signaling, and possibly involving its down-stream effector adenylate cyclase that produces the second messenger cyclic adenosine-3′, 5′-monophosphate (cAMP). Here we find that mutation in torsinA induces ER stress, and inhibits the cyclic adenosine-3′, 5′-monophosphate (cAMP) response to the adenylate cyclase agonist forskolin. Both defective mechanins are corrected by the small molecule 4-phenylbutyrate (4-PBA) that alleviates ER stress. Our results link torsinA, the ER-stress-response, and cAMP-dependent signaling, and suggest 4-PBA could also be used in dystonia treatment. Other pharmacological agents known to modulate the cAMP cascade, and ER stress may also be therapeutic in dystonia patients and can be tested in the models described here, thus supplementing current efforts centered on the dopamine pathway
Two Gestational Sacs, Two Locations - Heterotopic Pregnancy - Case Report
Introduction: Heterotopic pregnancy (HP) is defined as two gestational sacs
simultaneously present in two different locations, being the uterus and the fallopian
tubes the more common. Sporadic HP is a very rare condition (1:30,000 pregnancies).
With the use of medically assisted reproduction the prevalence is significantly higher(1:7,000). Considering spontaneous pregnancy, HP is associated with risk factors, being prior inflammatory pelvic disease the most common. The clinical presentation is similar to that of ectopic pregnancy or spontaneous miscarriage although it is usually a more late diagnosis.
Case report: 25 year-old pregnant woman, OI 0000, previously healthy; admitted at the
Emergency Department (ED) with acute pelvic pain mainly at the right iliac fossa and
moderate vaginal bleeding confirmed by speculum examination. She was
hemodynamically stable and the bimanual palpation was painful; no prior medically
assisted reproduction technique had been performed. The haemoglobin value was within
normal range and the serum β-hCG was 2,763mUI/mL. The ultrasonography at the ED
showed an in uterus gestational sac and another one inside the right fallopian tube; in both gestational sacs cardiac activity was absent.
HP diagnosis was then established and the patient was admitted at the Obstetrics Ward
for surveillance and ultrasonographic/laboratorial reassessment; complete miscarriage of the uterine pregnancy occurred but methotrexate was necessary for the treatment of persistent tubarian pregnancy.
Conclusion: When evaluating a pregnant woman with pelvic pain and vaginal bleeding
one should always be aware of several differential diagnosis amongst which HP should be considered. If the patient has in uterus viable pregnancy the treatment of the ectopic concomitant gestational sac should be as conservative as possible; methotrexate should not be used in that situation as it leads to uterine pregnancy miscarriage in about one third of the patients
Introdução e avaliação de forrageiras em pastagens nativas da Ilha de Marajó.
Resumo publicado também em: REUNIÃO ANUAL DA SOCIEDADE BRASILEIRA DE ZOOTECNIA, 36., 1999, Porto Alegre. Resumos dos trabalhos apresentados... Porto Alegre: Sociedade Brasileira de Zootecnia, 1999. p. 71
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