970 resultados para Hypoglycemia, congenital
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1. Eight human cytochrome P4501B1 (CYP1B1) allelic variants, namely Arg(48)Ala(119)Leu(432), Arg(48)Ala(119)Val(432), Gly(48)Ala(119)Leu(432), Gly(48)Ala(119)Val(432), Arg(48)Ser(119)Leu(432), Arg(48)Ser(119)Val(432), Gly(48)Ser(119)Leu(432) and Gly(48)Ser(119)Val(432) (all with Asn(453)), were expressed in Escherichia coli together with human NADPH-P450 reductase and their catalytic specificities towards oxidation of 17 beta -oestradiol and benzo[a]pyrene were determined. 2. All of the CYP1B1 variants expressed in bacterial membranes showed Fe2+. CO versus Fe2+ difference spectra with wavelength maxima at 446 nm and they reacted with antibodies raised against recombinant human CYP1B1 in immunoblots. The ratio of expression of the reductase to CYP1B1 in these eight preparations ranged from 0.2 to 0.5. 3. CYP1B1 Arg(48) variants tended to have higher activities for 17 beta -oestradiol 4-hydroxylation than Gly(48) variants, although there were no significant variations in 17 beta -oestradiol 2-hydroxylation activity in these eight CYP1B1 variants. Interestingly, ratios of formation of 17 beta -oestradiol 4-hydroxylation to 2-hydroxylation by these CYP1B1 variants were higher in all of the Val(432) forms than the corresponding Leu(432) forms. 4. In contrast, Leu(432) forms of CYP1B1 showed higher rates of oxidation of benzo[a]pyrene (to the 7, 8-dihydoxy-7,8-dihydrodiol in the presence of epoxide hydrolase) than did the Val(432) forms. 5. These results suggest that polymorphic human CYP1B1 variants may cause some altered catalytic specificity with 17 beta -oestradiol and benzo[a]pyrene and may influence susceptibilities of individuals towards endogenous and exogenous carcinogens.
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Adipose tissue is a highly active endocrine organ secreting a range of soluble products with both local and distant actions. These hormones have important roles in metabolism, reproduction, cardiovascular function and immunity. It is now evident that adipose endocrine function directly influences other organ systems, including the brain, liver and skeletal muscle. The endocrine function of adipose tissue is significantly regulated by nutritional status, and both are inextricably linked to the energy storage role of adipose tissue. This chapter highlights the endocrinology of adipose tissue by concentrating on functional aspects of the secreted products. The data of particular relevance to humans are highlighted, and areas in need of future research are suggested.
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OBJECTIVE - To assess the timing of fetal growth spurt among pre-existing diabetic pregnancies (types 1 and 2) and its relationship with diabetic control. To correlate fetal growth acceleration with factors that might influence fetal growth. RESEARCH DESIGN AND METHODS - This retrospective study involved all pregestational diabetic pregnancies delivered at a tertiary obstetric hospital in Australia between 1 January 1994 and 31 December 1999. Pregnancies with major congenital fetal anomalies, multiple pregnancies, small-for-gestational-age pregnancies (90th centile for gestation) were compared with babies with normal birth weights. RESULTS- A total of 101 diabetic pregnancies were included. Diabetic mothers, who had LGA babies, had significantly higher prepregnancy body weight and BMI (P < 0.05). There were no differences in maternal age or parity among the two groups. There were also no differences in the first-, second-, and third-trimester HbA(1c) levels between the two groups. The abdominal circumference z-scores were significantly higher for LGA babies from 18 weeks and thereafter. The differences increased progressively as the gestation advanced. Maximum difference was noted in the third trimester (30-38 weeks). CONCLUSIONS - Fetal growth acceleration in LGA fetuses of diabetic mothers starts in the second trimester, from as early as 18 weeks. In this study, glucose control did not appear to have a direct effect on the incidence of LGA babies, and such observation might result from the effects of other confounding factors.
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Objectives To assess the detection rate of congenital fetal malformations and specific problems related to routine ultrasound screening in women with pre-existing diabetes. Methods A retrospective study was carried out to assess the performance of routine ultrasound screening in women with pre-existing diabetes (Types 1 and 2) within a tertiary institution. The incidence, type and risk factors for congenital fetal malformations were determined. The detection rate of fetal anomalies for diabetic women was compared with that for the low-risk population. Factors affecting these detection rates were evaluated. Results During the study period, 12 169 low-risk pregnant women and 130 women with pre-existing diabetes had routine ultrasound screening performed within the institution. A total of 10 major anomalies (7.7%) and three minor anomalies (2.3%) were present in the fetuses of the diabetic women. Central nervous system and cardiovascular system anomalies accounted for 60% of the major anomalies. Peri-conceptional hemoglobin A 1 c of more than 9% was associated with a high prevalence of major anomalies (14311000). Women who had fetuses with major anomalies bad a significantly higher incidence of obesity (78% vs. 37%; P < 0.05). Ultrasound examination of these diabetic pregnancies showed high incidences of suboptimal image quality (37%), incomplete examinations, and repeat examinations (17%). Compared to the 'low-risk' non-diabetic population from the same institution, the relative risk for a major congenital anomaly among the diabetic women was 5.9-fold higher (95% confidence interval, 2.9-11.9). The detection rate for major fetal anomalies was significantly lower for diabetic women (30% vs. 73%; P < 0.01), and the mean body mass index for the diabetic group was significantly higher (29 vs. 23 kg/m(2); P < 0.001). Conclusion The incidence of congenital anomalies is higher in diabetic pregnancies. Unfortunately, the detection rate for fetal anomalies by antenatal ultrasound scan was significantly, worse than that for the low-risk population. This is likely to be related to the maternal body habitus and unsatisfactory examinations. Methods to overcome these difficulties are discussed.
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Objective. This is an over-view of the cellular biology of upper nasal mucosal cells that have special characteristics that enable them to be used to diagnose and study congenital neurological diseases and to aid neural repair. Study Design: After mapping the distribution of neural cells in the upper nose, the authors' investigations moved to the use of olfactory neurones to diagnose neurological diseases of development, especially schizophrenia. Olfactory-ensheating glial cells (OEGs) from the cranial cavity promote axonal penetration of the central nervous system and aid spinal cord repair in rodents. The authors sought to isolate these cells from the more accessible upper nasal cavity in rats and in humans and prove they could likewise promote neural regeneration, making these cells suitable for human spinal repair investigations. Methods: The schizophrenia-diagnosis aspect of the study entailed the biopsy of the olfactory areas of 10 schizophrenic patients and 10 control subjects. The tissue samples were sliced and grown in culture medium. The ease of cell attachment to fibronectin (artificial epithelial basement membrane), as well as the mitotic and apoptotic indices, was studied in the presence and absence of dopamine in those cell cultures. The neural repair part of the study entailed a harvesting and insertion of first rat olfactory lamina propria rich in OEGs between cut ends of the spinal cords and then later the microinjection of an OEG-rich suspension into rat spinal cords previously transected by open laminectomy. Further studies were done in which OEG insertion was performed up to 1 month after rat cord transection and also in monkeys. Results: Schizophrenic patients' olfactory tissues do not easily attach to basement membrane compared with control subjects, adding evidence to the theory that cell wall anomalies are part of the schizophrenic lesion of neurones. Schizophrenic patient cell cultures had higher mitotic and apoptotic indices compared with control subjects. The addition of dopamine altered these indices enough to allow accurate differentiation of schizophrenics from control patients, leading to, possibly for the first time, an early objective diagnosis of schizophrenia and possible assessment of preventive strategies. OEGs from the nose were shown to be as effective as those from the olfactory bulb in promoting axonal growth across transected spinal cords even when added I month after injury in the rat. These otherwise paraplegic rats grew motor and proprioceptive and fine touch fibers with corresponding behavioral improvement. Conclusions. The tissues of the olfactory mucosa are readily available to the otolaryngologist. Being surface cells, they must regenerate (called neurogenesis). Biopsy of this area and amplification of cells in culture gives the scientist a window to the developing brain, including early diagnosis of schizophrenia. The Holy Grail of neurological disease is the cure of traumatic paraplegia and OEGs from the nose promote that repair. The otolaryngologist may become the necessary partner of the neurophysiologist and spinal surgeon to take the laboratory potential of paraplegic cure into the day-to-day realm of clinical reality.
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Background - Marfan syndrome (MS) is a genetic disorder caused by a mutation in the fibrillin gene FBN1. Bicuspid aortic valve (BAV) is a congenital heart malformation of unknown cause. Both conditions are associated with ascending aortic aneurysm and premature death. This study examined the relationship among the secretion of extracellular matrix proteins fibrillin, fibronectin, tenascin, and vascular smooth muscle cell (VSMC) apoptosis. The role of matrix metalloproteinase (MMP)- 2 in VSMC apoptosis was studied in MS aneurysm. Methods and Results - Aneurysm tissue was obtained from patients undergoing surgery ( MS: 4 M, 1 F, age 27 - 45 years; BAV: 3 M, 2 F, age 28 - 65 years). Normal aorta from subjects with nonaneurysm disease was also collected ( 4 M, 1 F, age 23 - 93 years). MS and BAV aneurysm histology showed areas of cystic medial necrosis (CMN) without inflammatory infiltrate. Immunohistochemical study of cultured MS and BAV VSMC showed intracellular accumulation and reduction of extracellular distribution of fibrillin, fibronectin, and tenascin. Western blot showed no increase in expression of fibrillin, fibronectin, or tenascin in MS or BAV VSMC and increased expression of MMP-2 in MS VSMCs. There was 4-fold increase in loss of cultured VSMC incubated in serum-free medium for 24 hours in both MS ( 27 +/- 8%) and BAV ( 32 +/- 14%) compared with control ( 7 +/- 5%). Conclusions - In MS and BAV there is alteration in both the amount and quality of secreted proteins and an increased degree of VSMC apoptosis. Up-regulation of MMP-2 might play a role in VSMC apoptosis in MS VSMC. The findings suggest the presence of a fundamental cellular abnormality in BAV thoracic aorta, possibly of genetic origin.
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Mutations in the E1alpha subunit of the pyruvate dehydrogenase multienzyme complex may result in congenital lactic acidosis, but little is known about the consequences of these mutations at the enzymatic level. Here we characterize two mutants (F205L and T231A) of human pyruvate dehydrogenase in vitro, using the enzyme expressed in Escherichia coli. Wild-type and mutant proteins were purified successfully and their kinetic parameters were measured. F205L shows impaired binding of the thiamin diphosphate cofactor, which may explain why patients carrying this mutation respond to high-dose vitamin B-1 therapy. T231A has very low activity and a greatly elevated K-m for pyruvate, and this combination of effects would be expected to result in severe lactic acidosis. The results lead to a better understanding of the consequences of these mutations on the functional and structural properties of the enzyme, which may lead to improved therapies for patients carrying these mutations.
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Background: Glucose-insulin-potassium (GIK) infusion improves cardiac function and outcome during acute ischaemia. Objective: To determine whether GIK infusion benefits patients with chronic ischaemic left ventricular dysfunction, and if so whether this is related to the presence and nature of viable myocardium. Methods: 30 patients with chronic ischaemic left ventricular dysfunction had dobutamine echocardiography and were given a four hour infusion of GIK. Segmental responses were quantified by improvement in wall motion score index (WMSI) and peak systolic velocity using tissue Doppler. Global responses were assessed by left ventricular volume and ejection fraction, measured using a three dimensional reconstruction. Myocardial perfusion was determined in 15 patients using contrast echocardiography. Results: WMSI (mean (SD)) improved with dobutamine (from 1.8 (0.4) to 1.6 (0.4), p < 0.001) and with GIK (from 1.8 (0.4) to 1.7 (0.4) p < 0.001); there was a similar increment for both. Improvement in wall motion score with GIK was observed in 55% of the 62 segments classed as viable by dobutamine echocardiography, and in 5% of 162 classed as non-viable. There was an increment in peak systolic velocity after both doputamine echocardiography (from 2.5 (1.8) to 3.2 (2.2) cm/s, p < 0.01) and GIK (from 3.0 (1.6) to 3.5 (17) cm/s, p < 0.001). The GlK effects were not mediated by changes in pulse, mean arterial pressure, lactate, or catecholamines, nor did they correlate with myocardial perfusion. End systolic volume improved after GlK (p = 0.03), but only in 25 patients who had viable myocardium on dobutom ne echocardiography. Conclusions: In patients with viable myocardium and chronic left ventricular dysfunction, GlK improves wall motion score, myocardial velocity, and end systolic volume, independent of effects on haemodynamics or catecholamines. The response to GlK is observed in areas of normal and abnormal perfusion assessed by contrast echocardiography.
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A retinocoroidite é a manifestação mais comum causada pela infecção congênita por Toxoplasma gondii. Devido a gravidade das lesões oculares que podem até levar à perda completa da visão, a detecção precoce da toxoplasmose congênita e da lesão ocular são essenciais para o tratamento. Este trabalho possuiu o objetivo de avaliar a aplicabilidade da pesquisa de anticorpos IgG e das subclasses IgG1, IgG2, IgG3 e IgG4 anti-T. gondii por citometria de fluxo como marcador laboratorial das diferentes formas de lesões retinocoroidais na toxoplasmose congênita. Foram analisadas 88 amostras de soro de recém-nascidos com toxoplasmose congênita, sendo 25 sem lesão ocular (SL), 10 com lesão ocular ativa (RA), 26 com lesão ocular ativa e cicatricial (RAC) e 27 com lesão ocular cicatricial (RC). Foram também utilizadas 19 amostras de soro de recém-nascidos não infectados que apresentaram IgG positivo após o nascimento (NI). Essas amostras foram obtidas a partir de soros de recémnascidos participantes de um programa de triagem neonatal realizado em Minas Gerais realizado nos anos de 2006 e 2007. Os resultados demonstraram que os recém-nascidos com toxoplasmose congênita apresentam maior reatividade de anticorpos IgG total e subclasses IgG1, IgG2 e IgG3 do que indivíduos não infectados. No grupo não infectado, o único anticorpo com mais de 50% de indivíduos com alta reatividade de anticorpos foi IgG4. Ao comparar os grupos de indivíduos com toxoplasmose congênita, foi observado que o grupo RAC, seguido de RC, apresentou maior reatividade principalmente para os anticorpos IgG1 e IgG3 comparado aos recém-nascidos dos grupos RA e SL, enquanto que pacientes do grupo RA apresentaram maior reatividade para IgG4 do que indivíduos dos outros grupos. IgG1 foi a única subclasse capaz de diferenciar os grupos NI, SL dos grupos RAC e RC. Também foi avaliado o índice de avidez de IgG total, que não permitiu estabelecer nenhum critério de diferenciação das formas de lesão ocular causadas pelo T. gondii. Portanto, a citometria de fluxo demonstrou que pode ser um método laboratorial complementar para ser utilizado como indicador das diferentes lesões oculares causadas pela toxoplasmose congênita.
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Pectus excavatum is the most common congenital deformity of the anterior chest wall, in which several ribs and the sternum grow abnormally. Nowadays, the surgical correction is carried out in children and adults through Nuss technic. This technic has been shown to be safe with major drivers as cosmesis and the prevention of psychological problems and social stress. Nowadays, no application is known to predict the cosmetic outcome of the pectus excavatum surgical correction. Such tool could be used to help the surgeon and the patient in the moment of deciding the need for surgery correction. This work is a first step to predict postsurgical outcome in pectus excavatum surgery correction. Facing this goal, it was firstly determined a point cloud of the skin surface along the thoracic wall using Computed Tomography (before surgical correction) and the Polhemus FastSCAN (after the surgical correction). Then, a surface mesh was reconstructed from the two point clouds using a Radial Basis Function algorithm for further affine registration between the meshes. After registration, one studied the surgical correction influence area (SCIA) of the thoracic wall. This SCIA was used to train, test and validate artificial neural networks in order to predict the surgical outcome of pectus excavatum correction and to determine the degree of convergence of SCIA in different patients. Often, ANN did not converge to a satisfactory solution (each patient had its own deformity characteristics), thus invalidating the creation of a mathematical model capable of estimating, with satisfactory results, the postsurgical outcome
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Pectus excavatum is the most common congenital deformity of the anterior thoracic wall. The surgical correction of such deformity, using Nuss procedure, consists in the placement of a personalized convex prosthesis into sub-sternal position to correct the deformity. The aim of this work is the CT-scan substitution by ultrasound imaging for the pre-operative diagnosis and pre-modeling of the prosthesis, in order to avoid patient radiation exposure. To accomplish this, ultrasound images are acquired along an axial plane, followed by a rigid registration method to obtain the spatial transformation between subsequent images. These images are overlapped to reconstruct an axial plane equivalent to a CT-slice. A phantom was used to conduct preliminary experiments and the achieved results were compared with the corresponding CT-data, showing that the proposed methodology can be capable to create a valid approximation of the anterior thoracic wall, which can be used to model/bend the prosthesis
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Pectus excavatum is the most common congenital deformity of the anterior chest wall, in which an abnormal formation of the rib cage gives the chest a caved-in or sunken appearance. Today, the surgical correction of this deformity is carried out in children and adults through Nuss technic, which consists in the placement of a prosthetic bar under the sternum and over the ribs. Although this technique has been shown to be safe and reliable, not all patients have achieved adequate cosmetic outcome. This often leads to psychological problems and social stress, before and after the surgical correction. This paper targets this particular problem by presenting a method to predict the patient surgical outcome based on pre-surgical imagiologic information and chest skin dynamic modulation. The proposed approach uses the patient pre-surgical thoracic CT scan and anatomical-surgical references to perform a 3D segmentation of the left ribs, right ribs, sternum and skin. The technique encompasses three steps: a) approximation of the cartilages, between the ribs and the sternum, trough b-spline interpolation; b) a volumetric mass spring model that connects two layers - inner skin layer based on the outer pleura contour and the outer surface skin; and c) displacement of the sternum according to the prosthetic bar position. A dynamic model of the skin around the chest wall region was generated, capable of simulating the effect of the movement of the prosthetic bar along the sternum. The results were compared and validated with patient postsurgical skin surface acquired with Polhemus FastSCAN system
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O Registo Nacional de Anomalias Congénitas (RENAC) recebe notificações da ocorrência de anomalias congénitas diagnosticadas até ao final do 1º mês de vida, algumas das quais são raras. Foi realizado um estudo observacional, transversal, com a finalidade de descrever a epidemiologia dos registos de anomalias congénitas que constituem uma síndrome genética rara, utilizando os dados do RENAC entre 2000-2013. Observou-se uma prevalência de 1,17 casos/10 000 nascimentos de indivíduos com síndrome genética rara com anomalias que afetam múltiplos sistemas. Estas patologias representam um pequeno grupo do universo das doenças raras. No total das síndromes estudadas (n=171), a maior frequência observou-se no grupo de síndromes que afetam predominantemente o aspeto da face (50,9%) e, neste grupo, destacam-se a Sequência de Pierre Robin (26,3%) e a Síndrome de Goldenhar (11,7%). No grupo de outras síndromes genéticas, a Síndrome de DiGeorge foi diagnosticada em 12,3% dos casos. Dada a inexistência de um registo nacional de doenças raras, os dados do RENAC podem contribuir para avaliar a prevalência de algumas destas doenças. Contudo para uma melhor vigilância de algumas doenças raras, o prazo de registo será alargado até ao ano de idade de modo a permitir que situações mais complexas possam ser identificadas e registadas.