31 resultados para Intellectual and Developmental Disabilities
Resumo:
Congenital hyperinsulinism (CHI) is a rare pancreatic beta-cell disease of neonates, characterized by inappropriate insulin secretion with severe persistent hypoglycemia, with regard to which many questions remain to be answered, despite the important acquisition of its molecular mechanisms in the last decade. The aim of this study was to examine pancreatic histology, beta-cell proliferation (immunohistochemistry with double staining for Ki-67/insulin), and beta-cell adenosine triphosphate-sensitive potassium channels genes from 11 Brazilian patients with severe medically unresponsive CHI who underwent pancreatectomy. Pancreatic histology and beta-cell proliferation in CHI patients were compared to pancreatic samples from 19 age-matched controls. Ten cases were classified as diffuse form (D-CHI) and 1 as focal form (F-CHI). beta-cell nucleomegaly and abundant cytoplasm were absent in controls and were observed only in D-CHI patients. The Ki-67 labeling index (Ki-67-LI) was used to differentiate the adenomatous areas of the F-CHI case (10.15%) from the ""loose cluster of islets`` found in 2 D-CHI samples (2.29% and 2.43%) and 1 control (1.54%) sample. The Ki-67-LI was higher in the F-CHI adenomatous areas, but D-CHI patients also had significantly greater Ki-67-LI (mean value = 2.41%) than age-matched controls (mean value = 1.87%) (P = 0.009). In this 1st genetic study of CHI patients in Brazil, no mutations or new polymorphisms were found in the 33-37 exons of the ABCC8 gene (SUR1) or in the entire exon of the KCNJ11 gene (Kir 6.2) in 4 of 4 patients evaluated. On the other hand, enhanced beta-cell proliferation seems to be a constant feature in CHI patients, both in diffuse and focal forms.
Resumo:
Rearrangements of 1p36 are the most frequently detected abnormalities in diagnostic testing for chromosomal cryptic imbalances and include variably sized simple terminal deletions, derivative chromosomes, interstitial deletions, and complex rearrangements. These rearrangements result in the specific pattern of malformation and neurodevelopmental disabilities that characterizes monosomy 1p36 syndrome. Thus far, no individual gene within this region has been conclusively determined to be causative of any component of the phenotype. Nor is it known if the rearrangements convey phenotypes via a haploinsufficiency mechanism or through a position effect. We have used multiplex ligation-dependent probe amplification to screen for deletions of 1p36 in a group of 154 hyperphagic and overweight/obese, PWS negative individuals, and in a separate group of 83 patients initially sent to investigate a variety of other conditions. The strategy allowed the identification and delineation of rearrangements in nine subjects with a wide spectrum of clinical presentations. Our work reinforces the association of monosomy 1p36 and obesity and hyperphagia, and further suggests that these features may be associated with non-classical manifestations of this disorder in addition to a submicroscopic deletion of similar to 2-3 Mb in size. Multiplex ligation probe amplification using the monosomy 1p36 syndrome-specific kit coupled to the subtelomeric kit is an effective approach to identify and delineate rearrangements at 1p36. (C) 2009 Wiley-Liss, Inc.
Resumo:
Ipomoea carnea is a toxic plant that grows in tropical areas, and is readily consumed by grazing goats. The plant contains the alkaloids swainsonine and calystegines, which inhibit cellular enzymes and cause systematic cell death. This study evaluated the behavioral effects on dams and kids of prenatal ingestion of this plant. Freshly harvested leaves of I. carnea (10 g/kg body weight) were fed daily to nine pregnant goats from the fifth to the 16th week of gestation; five pregnant goats were controls. Dam and kid behavior were evaluated during 2-hr postpartum. Further evaluation of the offspring was performed using various tests after birth: (1) reaching and discriminating their dam from an alien doe (two tests at 12-hr postpartum), and (2) navigating a progressive maze (2, 4, and 6 days postpartum). Postnatal (n=2) and fetal (n=2) mortality were observed in the treated group. Intoxicated kids had difficulty in standing at birth, and only one was able to suckle within 2 hr of birth. Treated kids were slower than controls to arrive at their dam in the discrimination test; treated kids often (seven of nine completed tests) incorrectly chose the alien dam (controls: 0/10 tests). During some runs on days 2, 4, and 6 postpartum, treated kids were slower to leave the starting point of the maze, and were slower to arrive at the dam on all test days. This study suggests that the offspring of pregnant goats given I. carnea during gestation have significant behavioral alterations and developmental delays. Birth Defects Res (Part B) 92:131-138, 2011. (C) 2011 Wiley-Liss, Inc.
Resumo:
Transforming growth factor-beta (TGF-beta) is a multifunctional growth factor that has several biological effects in vivo including control of cell growth and differentiation, cell migration, lineage determination, motility, adhesion, apoptosis, and synthesis and degradation of extracellular matrix, and TGF-beta plays an important role in regulating tissue repair and regeneration. Our study analyzed the participation of TGF-beta 1, -beta 2, and -beta 3 in the different stages of morphogenesis and differentiation of human developing dental organ using immunobistochemistry. The maxillae and mandibles of 10 human embryos ranging from 8 to 23 weeks of gestation were employed, according to the approval of the ethical committee. Our study revealed that the TGF-beta subunits-beta 1, beta 2, and beta 3 were present in the various stages of tooth development, but the expression varied according to the differentiation stage, tissue, and TGF-beta subunit. Our results indicated that TGF-beta 1 is closely related to differentiation of enamel organ and initiation of matrix secretion, TGF-beta 2 to cellular differentiation, and TGF-beta 3 to mineral maturation matrix.
Resumo:
Since the advent of the postgenomic era, efforts have focused on the development of rapid strategies for annotating plant genes of unknown function. Given its simplicity and rapidity, virus-induced gene silencing (VIGS) has become one of the preeminent approaches for functional analyses. However, several problems remain intrinsic to the use of such a strategy in the study of both metabolic and developmental processes. The most prominent of these is the commonly observed phenomenon of ""sectoring"" the tissue regions that are not effectively targeted by VIGS. To better discriminate these sectors, an effective marker system displaying minimal secondary effects is a prerequisite. Utilizing a VIGS system based on the tobacco rattle virus vector, we here studied the effect of silencing the endogenous phytoene desaturase gene (pds) and the expression and subsequent silencing of the exogenous green fluorescence protein (gfp) on the metabolism of Arabidopsis (Arabidopsis thaliana) leaves and tomato (Solanum lycopersicum) fruits. In leaves, we observed dramatic effects on primary carbon and pigment metabolism associated with the photobleached phenotype following the silencing of the endogenous pds gene. However, relatively few pleiotropic effects on carbon metabolism were observed in tomato fruits when pds expression was inhibited. VIGS coupled to gfp constitutive expression revealed no significant metabolic alterations after triggering of silencing in Arabidopsis leaves and a mild effect in mature green tomato fruits. By contrast, a wider impact on metabolism was observed in ripe fruits. Silencing experiments with an endogenous target gene of interest clearly demonstrated the feasibility of cosilencing in this system; however, carefully constructed control experiments are a prerequisite to prevent erroneous interpretation.
Resumo:
Lianas are one of the most important components of tropical forest, and yet one of the most poorly known organisms. Therefore, our paper addresses questions on the environmental and developmental aspects that influence the growth of lianas of Bignoniaceae, tribe Bignonieae. In order to better understand their growth, we studied the stem anatomy, seasonality of formation and differentiation of secondary tissues, and the influence of the cambial variant in xylem development on a selected species: Tynanthus cognatus. Afterwards, we compared the results found in T. cognatus with 31 other species of Bignonieae to identify general patterns of growth in lianas of this tribe. We found that cambial activity starts toward the end of the rainy season and onset of the dry season, in contrast to what is known for tropical trees and shrubs. Moreover, their pattern of xylem formation and differentiation is strongly influenced by the presence of massive wedges of phloem produced by a variant cambium. Thus, the variant cambium is the first to commence its activity and only subsequently does cambial activity progress towards the center of the regular region, leading to the formation of confluent growth rings. In summary, we conclude that: the cambium responds to environmental changes; the xylem growth rings are annual and produced in a brief period of about 2 months, something that may explain why lianas possess narrow stems; and furthermore, phloem wedges greatly influence cambial activity.
Resumo:
An organism is built through a series of contingent factors, yet it is determined by historical, physical, and developmental constraints. A constraint should not be understood as an absolute obstacle to evolution, as it may also generate new possibilities for evolutionary change. Modularity is, in this context, an important way of organizing biological information and has been recognized as a central concept in evolutionary biology bridging on developmental, genetics, morphological, biochemical, and physiological studies. In this article, we explore how modularity affects the evolution of a complex system in two mammalian lineages by analyzing correlation, variance/covariance, and residual matrices (without size variation). We use the multivariate response to selection equation to simulate the behavior of Eutheria and Metharia skulls in terms of their evolutionary flexibility and constraints. We relate these results to classical approaches based on morphological integration tests based on functional/developmental hypotheses. Eutherians (Neotropical primates) showed smaller magnitudes of integration compared with Metatheria (didelphids) and also skull modules more clearly delimited. Didelphids showed higher magnitudes of integration and their modularity is strongly influenced by within-groups size variation to a degree that evolutionary responses are basically aligned with size variation. Primates still have a good portion of the total variation based on size; however, their enhanced modularization allows a broader spectrum of responses, more similar to the selection gradients applied (enhanced flexibility). Without size variation, both groups become much more similar in terms of modularity patterns and magnitudes and, consequently, in their evolutionary flexibility. J. Exp. Zool. (Mol. Dev. Evol.) 314B:663-683, 2010. (C) 2010 Wiley-Liss, Inc.
Resumo:
The first studies concerning the embryonic development of harvestmen started in the late 19th century, and focused mostly on holarctic species, and only three species of the suborder Laniatores (the largest, among the four suborders considered presently) were studied. Moreover, the last studies on embryology of harvestmen were made during the late 1970s. This study focused on the embryonic development of Ampheres leucopheus (Gonyleptidae, Caelopyginae) and Iporangaia pustulosa (Gonyleptidae, Progonyleptoidellinae). The embryonic development was followed in the field, by taking daily photographs of different eggs during about 2 months. When laid, eggs of A. leucopheus and I pustulosa have approximately 1.13 and 1.30 mm in diameter, respectively, and the second is embedded in a large amount of mucus. The eggs grow, mainly due to water absorption at the beginning of the process, and they reach a diameter of about 1.35 and 1.59 mm, respectively, close to hatching. It took, respectively, 29-56 days and 35-66 days from egg laying to hatching. For the description of the embryonic development, we use photographs from the field, SEM micrographs, and histological analysis. This allowed us, for instance, to document the progression of structures and pigmentation directly from live embryos in the field, and to record microstructures, such as the presence of perforations in the cuticle of the embryo in the place where eyes are developing. Yet, contrary to what was expected in the literature, we record an egg tooth in one of the studied laniatoreans. J. Exp. Zool. (Mol. Dev. Evol) 314B:489-502, 2010. (C) 2010 Wiley-Liss, Inc.
Resumo:
One of the most fascinating aspects of plant morphology is the regular geometric arrangement of leaves and flowers, called phyllotaxy. The shoot apical meristem (SAM) determines these patterns, which vary depending on species and developmental stage. Auxin acts as an instructive signal in leaf initiation, and its transport has been implicated in phyllotaxy regulation in Arabidopsis (Arabidopsis thaliana). Altered phyllotactic patterns are observed in a maize (Zea mays) mutant, aberrant phyllotaxy1 (abph1, also known as abphyl1), and ABPH1 encodes a cytokinin-inducible type A response regulator, suggesting that cytokinin signals are also involved in the mechanism by which phyllotactic patterns are established. Therefore, we investigated the interaction between auxin and cytokinin signaling in phyllotaxy. Treatment of maize shoots with a polar auxin transport inhibitor, 1-naphthylphthalamic acid, strongly reduced ABPH1 expression, suggesting that auxin or its polar transport is required for ABPH1 expression. Immunolocalization of the PINFORMED1 (PIN1) polar auxin transporter revealed that PIN1 expression marks leaf primordia in maize, similarly to Arabidopsis. Interestingly, maize PIN1 expression at the incipient leaf primordium was greatly reduced in abph1 mutants. Consistently, auxin levels were reduced in abph1, and the maize PIN1 homolog was induced not only by auxin but also by cytokinin treatments. Our results indicate distinct roles for ABPH1 as a negative regulator of SAM size and a positive regulator of PIN1 expression. These studies highlight a complex interaction between auxin and cytokinin signaling in the specification of phyllotactic patterns and suggest an alternative model for the generation of altered phyllotactic patterns in abph1 mutants. We propose that reduced auxin levels and PIN1 expression in abph1 mutant SAMs delay leaf initiation, contributing to the enlarged SAM and altered phyllotaxy of these mutants.
Resumo:
OBJETIVO: investigar o conhecimento dos professores de 1ª a 4ª série quanto ao distúrbio da leitura e escrita, pesquisando quais dificuldades referentes a esse distúrbio, foram apresentadas por estes professores. MÉTODOS: esses dados foram obtidos, por meio de um questionário informativo de 10 questões, aplicados a 50 professores de 1ª a 4ª série, da cidade de Bauru. Os questionários foram analisados e tabulados, e receberam tratamento estatístico pertinente. RESULTADOS: os resultados obtidos revelaram que os professores possuem um conhecimento superficial a respeito do distúrbio da leitura e escrita, sendo que muitos adquiriram tal conhecimento fora do ambiente de graduação. Verificou-se também que os professores apesar de encaminharem seus alunos ao fonoaudiólogo, possuem visão limitada quanto à atuação deste profissional. O distúrbio da leitura e escrita foi considerado como um problema próprio da criança, sendo pouco reconhecido como uma falha que também pode ser da escola ou da metodologia de ensino. CONCLUSÃO: os professores logram um saber pouco fundamentado a respeito do distúrbio da leitura e escrita; sendo que, as dificuldades giraram em torno: da identificação real do problema; de quais manifestações caracterizam esse problema; e de como intervir e prevenir.
Resumo:
OBJETIVO: Analisar o consumo de medicamentos e os principais grupos terapêuticos consumidos por pessoas com deficiências físicas, auditivas ou visuais. MÉTODOS: Estudo transversal em que foram analisados dados do Inquérito Multicêntrico de Saúde no Estado de São Paulo (ISA-SP) em 2002 e do Inquérito de Saúde no Município de São Paulo (ISA-Capital), realizado em 2003. Os entrevistados que referiram deficiências foram estudados segundo as variáveis que compõem o banco de dados: área, sexo, renda, faixa etária, raça, consumo de medicamentos e tipos de medicamentos consumidos. RESULTADOS: A percentagem de consumo entre as pessoas com deficiência foi de: 62,8 por cento entre os visuais; 60,2 por cento entre os auditivos e 70,1 por cento entre os físicos. As pessoas com deficiência física consumiram 20 por cento mais medicamentos que os não-deficientes. Entre as pessoas com deficiência visual, os medicamentos mais consumidos foram os diuréticos, agentes do sistema renina-angiotensina e analgésicos. Pessoas com deficiência auditiva utilizaram mais analgésicos e agentes do sistema renina-angiotensina. Entre indivíduos com deficiência física, analgésicos, antitrombóticos e agentes do sistema renina-angiotensina foram os medicamentos mais consumidos. CONCLUSÕES: Houve maior consumo de medicamentos entre as pessoas com deficiências quando comparados com os não-deficientes, sendo os indivíduos com deficiência física os que mais consumiram fármacos, seguidos de deficientes visuais e auditivos
Resumo:
The aim of this study was to verify the efficacy of a programme for dental plaque control in autistics. Patients were evaluated on five occasions over a period of 180 days using the following instruments: OHI-S, DMF-T, the Fonnes brushing technique and diet questionnaire. Participants were divided into two groups according to level of co-operation on the programme: Group A (co-operative) and Group B (non-cooperative). A statistically significant improvement (p < 0.001) in Oral Hygiene was attained, with 84.2% showing regular or satisfactory hygiene at study end-point. Conclusion: Groups A and B both showed improvement in hygiene (p < 0.001 and p = 0.004), but improvement was significantly higher among co-operative patients (p < 0.001 at 180 days), who also had a higher mean age (p = 0.02).
Resumo:
Aldehyde dehydrogenases (ALDHs) catabolize toxic aldehydes and process the vitamin A-derived retinaldehyde into retinoic acid (RA), a small diffusible molecule and a pivotal chordate morphogen. In this study, we combine phylogenetic, structural, genomic, and developmental gene expression analyses to examine the evolutionary origins of ALDH substrate preference. Structural modeling reveals that processing of small aldehydes, such as acetaldehyde, by ALDH2, versus large aldehydes, including retinaldehyde, by ALDH1A is associated with small versus large substrate entry channels (SECs), respectively. Moreover, we show that metazoan ALDH1s and ALDH2s are members of a single ALDH1/2 clade and that during evolution, eukaryote ALDH1/2s often switched between large and small SECs after gene duplication, transforming constricted channels into wide opened ones and vice versa. Ancestral sequence reconstructions suggest that during the evolutionary emergence of RA signaling, the ancestral, narrow-channeled metazoan ALDH1/2 gave rise to large ALDH1 channels capable of accommodating bulky aldehydes, such as retinaldehyde, supporting the view that retinoid-dependent signaling arose from ancestral cellular detoxification mechanisms. Our analyses also indicate that, on a more restricted evolutionary scale, ALDH1 duplicates from invertebrate chordates (amphioxus and ascidian tunicates) underwent switches to smaller and narrower SECs. When combined with alterations in gene expression, these switches led to neofunctionalization from ALDH1-like roles in embryonic patterning to systemic, ALDH2-like roles, suggesting functional shifts from signaling to detoxification.
Resumo:
Peripheral nerves are structures that, when damaged, can result in significant motor and sensory disabilities. Several studies have used therapeutic resources with the aim of promoting early nerve regeneration, such as the use of low-power laser. However, this laser therapy does not represent a consensus regarding the methodology, thus yielding controversial conclusions. The objective of our study was to investigate, by functional evaluation, the comparative effects of low-power laser (660 nm and 830 nm) on sciatic nerve regeneration following crushing injuries. Twenty-seven Wistar rats subjected to sciatic nerve injury were divided into three groups: group sham, consisting of rats undergoing simulated irradiation; a group consisting of rats subjected to gallium-aluminum-arsenide (GaAlAs) laser at 660 nm (10 J/cm(2), 30 mW and 0.06 cm(2) beam), and another one consisting of rats subjected to GaAlAs laser at 830 nm (10 J/cm(2), 30 mW and 0.116 cm(2)). Laser was applied to the lesion for 21 days. A sciatic functional index (SFI) was used for functional evaluation prior to surgery and on days 7, 14, and 21 after surgery. Differences in SFI were found between group 660 nm and the other ones at the 14th day. One can observe that laser application at 660 nm with the parameters and methods utilised was effective in promoting early functional recovery, as indicated by the SFI, over the period evaluated.
Resumo:
PURPOSE. Surgical recession of an extraocular muscle (EOM) posterior to its original insertion is a common form of strabismus surgery, weakening the rotational force exerted by the muscle on the globe and improving eye alignment. The purpose of this study was to assess myosin heavy chain (MyHC) isoform expression and satellite cell activity as defined by Pax7 expression in recessed EOMs of adult rabbits compared with that in muscles tenotomized but not recessed and with that in normal control muscles. METHODS. The scleral insertion of the superior rectus muscle was detached and sutured either 7 mm posterior to its original insertion site (recession surgery) or at the same site (tenotomy). One day before euthanatization, the rabbits received bromodeoxyuridine (BrdU) injections. After 7 and 14 days, selected EOMs from both orbits were examined for changes in fast, slow, neonatal, and developmental MyHC isoform expression, Pax7 expression, and BrdU incorporation. RESULTS. Recession and tenotomy surgery resulted in similar changes in the surgical EOMs. These included a decreased proportion of fast MyHC myofibers, an increased proportion of slow MyHC myofibers, and increased BrdU-positive satellite cells. Similar changes were seen in the non-operated contralateral superior rectus muscles. The ipsilateral inferior rectus showed reciprocal changes to the surgical superior rectus muscles. CONCLUSIONS. The EOMs are extremely adaptive to changes induced by recession and tenotomy surgery, responding with modulations in fiber remodeling and myosin expression. These adaptive responses could be manipulated to improve surgical success rates. (Invest Ophthalmol Vis Sci. 2010;51:5646-5656) DOI:10.1167/iovs.10-5523