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71.
AIM: To describe the seasonal pattern of growth and analyse the relationship between weight and height gain in children under 3 y of age. METHODS: A population-based cohort of 767 children was prospectively followed from birth until 36 mo of age in rural Malawi, southeast Africa. Weight and height measurements were collected at monthly intervals until 18 mo of age and quarterly thereafter. Gains in weight and height and prevalence of malnutrition in different seasons were calculated. The relationship between weight and height gain was analysed using a series of correlation analyses. RESULTS: Both weight gain and linear growth velocity showed an age-dependent seasonal pattern. After infancy, periods of maximal or minimal height increments systematically occurred 3 mo after those for weight gain. The prevalence of malnutrition also followed a seasonal pattern, peaking a few months after periods of reduced growth. Despite the overall pattern, weight gain and subsequent linear growth were not correlated on an individual level. At any point, however, a child's weight for height was directly, albeit weakly, correlated to height gain in the subsequent 3-mo interval. CONCLUSION: Growth of children under 3 y of age followed an age-dependent seasonal pattern. The poor correlation between children's weight and height increments suggests that seasonality affected weight gain and linear growth through different mechanisms.  相似文献   
72.
BACKGROUND: Patients with wheat-dependent, exercise-induced anaphylaxis (WDEIA) experience recurrent anaphylactic reactions when exercising after ingestion of wheat products. We have identified omega-5 gliadin (Tri a 19) as a major allergen in WDEIA, but the role of exercise in eliciting the symptoms remains obscure. OBJECTIVE: The aim was to examine whether tissue transglutaminase (tTG)-mediated cross-linking could be involved in modulating the IgE-binding ability and in vivo reactivity of digested omega-5 gliadin peptides in WDEIA. METHODS: Purified omega-5 gliadin was digested with pepsin or with pepsin and trypsin and treated with tTG. The binding of IgE antibodies in pooled sera from 10 patients with WDEIA was studied by means of immunoblotting before and after tTG treatment of the digested peptides. The peptides derived from pepsin digestion were separated by means of gel-filtration chromatography, and IgE reactivity of 4 different peptide fractions was studied by immunoblotting before and after tTG treatment. The fraction showing the greatest degree of cross-linking by tTG was further studied by means of IgE ELISA, ELISA inhibition, and skin prick testing. RESULTS: The IgE-binding ability of omega-5 gliadin was retained after pepsin and pepsin-trypsin digestion. tTG treatment of the whole peptic digest formed large peptide complexes, with molecular weights ranging from 40 to greater than 200 kd. These cross-linked aggregates bound IgE antibodies in immunoblotting more intensely than untreated, pepsin-digested, or pepsin-trypsin-digested omega-5 gliadin. A gel-filtration fraction of the whole peptic digest corresponding to the highest peak of the chromatogram and showing the greatest degree of tTG-mediated cross-linking showed an increase in serum IgE reactivity in ELISA after tTG treatment, as well as a shift of reactivity to cross-linked complexes. In the 20 patients with WDEIA, the mean skin prick test wheal elicited by this tTG-treated peptic fraction was 77% larger (P <.001) than that elicited by the untreated peptic fraction and 56% larger (P <.01) than that elicited by intact omega-5 gliadin. CONCLUSIONS: Omega-5 gliadin-derived peptides are cross-linked by tTG, which causes a marked increase in IgE binding both in vitro and in vivo. Activation of tTG during exercise in the intestinal mucosa of patients with WDEIA could lead to the formation of large allergen complexes capable of eliciting anaphylactic reactions.  相似文献   
73.
The purpose of this study was to develop a convenient methodology for the coculture of autologous melanocytes and keratinocytes for grafting of patients with vitiligo. While grafting of pure melanocytes may achieve repigmentation, the inclusion of keratinocytes ensures rapid reepithelialization. Previously we have used confluent sheets of keratinocytes (with melanocytes present) to transfer cells. However, we found that as the keratinocyte density increased, melanocyte number and function were downregulated. Accordingly in this study we explored combinations of three culture surfaces and three media, seeking to achieve subconfluent culture of primary keratinocytes with a reasonable density of melanocytes, using cells immediately after isolation from skin. For this in vitro study, the surfaces studied were uncoated glass coverslips, and glass coverslips coated with collagen I or a nitrogen-containing plasma polymer. The results show that both the substrate surface and the medium composition influence the proliferation and survival of melanocytes. Keratinocytes and melanocytes could be successfully cocultured on a chemically defined plasma polymer substrate using a serum-free medium.  相似文献   
74.
Stunting is common among children under 5 y of age in sub-Saharan Africa. Several risk factors have been associated with poor growth but few studies have prospectively addressed the development of linear growth faltering and stunting during the first year of life. The present study was designed to analyse typical growth among rural Malawian infants, focusing particularly on the impact of birth size, adherence to feeding guidelines and morbidity in the development of severe stunting during infancy. A community-based cohort of 613 singleton newborns was prospectively followed by monthly home visits. Data were collected on the children's socioeconomic background, maternal size and weight gain during pregnancy, birth events, morbidity, breastfeeding and complementary feeding, growth and mortality. Univariate and multivariate analyses were used to determine associations between predictor variables and poor linear growth. The proportions of stunted infants (Height-for-age Z-score 3 32) at 3, 6 and 9 mo of age were 27%, 51%, and 63%, respectively. At 1 y of age, over two-thirds (71%) of the infants were at least moderately (HAZ 3 32) and 31% severely stunted (HAZ 3 33). Conclusion: The strongest predictor of severe stunting at 12 mo of age was small birth size. Other variables independently associated with this outcome included inappropriate complementary feeding, high morbidity, maternal short stature, male gender, and home delivery. Faltering of linear growth started soon after birth and continued throughout infancy. Interventions increasing birth size could have a significant role in the prevention of early childhood stunting. The ideal strategy should also emphasize the importance of appropriate infant feeding and decreasing the number of illness episodes amongst the infants.  相似文献   
75.
The rare case of limited range of motion of the shoulder due to ankylosis of the sternoclavicular joint in SAPHO syndrome is presented. The symptoms and the resection arthroplasty of the sternoclavicular joint are discussed.  相似文献   
76.
OBJECTIVE: This study determined the quantity and nature of emergencies leading to unscheduled hospital admissions of adults with congenital cardiac disease and their mid-term survival. RESULTS: During 1 year, 429 adults with congenital cardiac diseases were admitted 571 times, and 124 admissions (22%) of 95 patients (22%) were emergency admissions. Fifteen of the 95 patients were seen for the first time in 1 of the participating centers. The underlying anomalies were Fallot's tetralogy and pulmonary atresia (n = 26/7), univentricular heart after Fontan procedure (n = 25), atrial septal defect (n = 18), Eisenmenger syndrome (n = 12), complete transposition (n = 11), and others (n = 25). Indications for admission were cardiovascular complications (n = 103; 83%) (arrhythmia, cardiac failure, syncope, pacemaker problems, pericardial tamponade, and sudden death), infections (n = 8, 6%) (endocarditis, pacemaker infection, pneumonia, and cerebral abscess), acute chest pain (n = 7; 6%), and acute abdominal pain (n = 4; 3%). All patients required immediate emergency care, and 16 patients (17%) required urgent cardiovascular or abdominal surgery. Six patients died during the hospital stay. During a follow-up of 2.9 years (SD 0.8), 16 (18%) of the discharged patients died, and 2 additional patients underwent heart or heart-lung transplantation. CONCLUSION: Adults with congenital cardiac disease often experience serious emergency situations with a high in-hospital and mid-term post-hospital mortality. Care given by physicians with special expertise is important in this specific group of patients.  相似文献   
77.
The clinical manifestation of type 1 diabetes mellitus is preceded by an asymptomatic prodromal period called prediabetes or preclinical diabetes. It may last from a few months to several years, during which the autoimmune destruction of the insulin-producing beta-cells in the pancreas progresses. The genes on the human leukocyte antigen (HLA) and insulin gene region are major genetic determinants for genetic disease susceptibility, while dietary compounds and viral infections are the most likely environmental factors contributing to the etiopathogenesis. T cells are thought to be the effector cells for the beta-cell destruction, and glutamic acid decarboxylase, insulinoma-associated protein 2 and insulin represent the three major autoantigens. Autoantibodies are early detectable markers of an ongoing disease process and are used to diagnose prediabetes. Among first-degree relatives of patients with type 1 diabetes, the risk for clinical disease can be graded from <5% in those with one or no antibodies to >90% in individuals who carry the HLA-DQB1*02/0302 risk genotype and are positive for multiple autoantibodies. beta-Cell function may also be tested in autoantibody-positive individuals and low first-phase insulin response is highly predictive for rapid progression to the clinical disease. However, dynamic course and individual variation of the disease process complicates the disease prediction, and it is not known whether all individuals with signs of prediabetes will inevitably progress to clinical type 1 diabetes. Until clinically applicable prevention for the condition exists, the screening for the risk markers of type 1 diabetes should actively be undertaken only in the context of research projects. Several major national and international multicenter studies are ongoing to test the potential of various agents (e.g. insulin and nicotinamide) or early elimination of dietary compounds (e.g. cow's milk proteins) to delay or prevent the onset of clinical type 1 diabetes.  相似文献   
78.
In this study, we have used a combination of immunocytochemical and Ca(2+) imaging techniques to determine the functional localisation of insulin receptors as well as the potential role for insulin in modulating hippocampal synaptic activity. Comparison of insulin receptor and MAP2 labelling demonstrated extensive insulin receptor immunoreactivity on the soma and dendrites of cultured hippocampal neurones. Dual labelling with synapsin 1 also showed punctate insulin receptor labelling associated with synapses. In functional studies, insulin inhibited spontaneous Ca(2+) oscillations evoked in cultured hippocampal neurones following Mg(2+) removal. This action of insulin was mimicked by the ATP-sensitive K(+) (K(ATP)) channel opener diazoxide or the large conductance Ca(2+)-activated K(+) (BK) channel activator NS-1619. Furthermore, application of the K(ATP) channel blocker glybenclamide or the BK channel inhibitors iberiotoxin or charybdotoxin attenuated the actions of insulin, whereas prior incubation with a combination of glybenclamide and iberiotoxin completely blocked insulin action. The ability of insulin to modulate the Ca(2+) oscillations was reduced by the inhibitors of MAPK activation PD 98059 and U0126, but not by the PI 3-kinase inhibitors LY 294002 or wortmannin, indicating that a MAPK-driven process underlies insulin action. In conclusion, insulin inhibits spontaneous Ca(2+) oscillations via a process involving MAPK-driven activation of BK and K(ATP) channels. This process may be a useful therapeutic target for the treatment of epilepsy and certain neurodegenerative diseases.  相似文献   
79.
Transesophageal echocardiography (TEE) is a monitoring and diagnostic tool for the care of children undergoing cardiac surgery. We analyzed reports from 865 routine TEE examinations performed between January 1994 and March 2002 in patients younger than 17-yr-old who were undergoing surgery for congenital heart disease. Patients' median age was 36 mo (range, 1 day-16 yr). The primary end-point of the study was the incidence of surgical and medical management decisions changed as a result of TEE findings; secondary end-points were diagnostic impact (diagnostic exclusions and new diagnoses) and surgical outcome. Fifty percent of the examinations were performed by anesthesiologists with an advanced level of training in perioperative TEE; all of the examiners had an experience of >or=>500 TEE examinations. Supervision by an anesthesiologist with an advanced level of training was requested in 36.7% of cases; supervision by a cardiologist was requested in 3.8%. Surgical alterations of management were reported in 12.7% of cases and included the need for a repeat bypass run in 7.3%; medical alterations of management were required in 19.4% of cases. We observed a diagnostic impact of TEE in 18.5% of cases and a suboptimal but acceptable surgical outcome in 27.6%; TEE findings predicted postoperative difficulties in 4.0%. Our results confirm the utility of routine TEE to assess repair of congenital heart defects. Furthermore, this service was competently performed by a regular team of cardiac anesthesiologists appropriately trained in TEE. IMPLICATIONS: Transesophageal echocardiography (TEE) is an essential monitoring and diagnostic device for the care of children undergoing cardiac surgery. The surgical and medical impact of TEE is demonstrated in a large series of patients. This service can be performed by appropriately trained cardiac anesthesiologists.  相似文献   
80.
Bronchogenic cysts arise from an abnormal budding of the ventral diverticulum of the foregut or the tracheobronchial tree during embryogenesis. Rarely they develop within the pericardium. Symptoms of intrapericardial bronchogenic cysts such as chest pain, shortness of breath and arrhythmias can vary according to the location of the cyst, its size and compression of heart and vessels. In this case report we present a young women in whom the diagnosis of an intrapericardial bronchogenic cyst was made by echocardiography and later was approved intraoperatively.  相似文献   
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