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51.
de Jesus Machado Amorim R de Carvalho Lima M Cabral de Lira PI Emond AM 《Maternal & child nutrition》2011,7(3):295-306
Birthweight is recognized to be a determinant of a full term infant's early growth pattern; however, few studies have explored whether this effect is sustained into school age, especially in developing countries. We have used a cohort study from North East Brazil to investigate factors determining the anthropometric status of eight-year-old children born at full-term with low or appropriate weight. A cohort of 375 full-term infants was recruited at birth in six maternity hospitals between 1993 and 1994, in a poor region of the interior of the State of Pernambuco. At the age of 8 years, 86 born with low birthweight and 127 with appropriate birthweight were traced. Multivariable linear regression analyses were used to identify the net effect of socioeconomic conditions, maternal nutritional status and child factors on weight-for-age and height-for-age. An enter approach was used to estimate the contribution of different factors on child anthropometry. Birthweight had little influence on child nutritional status at school age. Maternal BMI and height together were the biggest contributors to variation in child weight-for-age (12.3%) and height-for-age (13.2%), followed by family socioeconomic conditions. Maternal height as a proxy of maternal constraint was the single factor that best explained the variation in both indices (6.2% for weight-for-age and 11.1% for height-for-age). Haemoglobin level measured at eight years made a small but significant contribution to variation in height-for-age (5.6%) and weight for age (1.4%). Maternal nutritional status, reflecting genetic inheritance and the poor socioeconomic conditions of this population, was the most important determinant of the nutritional status of children at school age, rather than birthweight. 相似文献
52.
Modulatory effect of NO on sodium currents in a neuroblastoma cell line: aspects of cell specificity
Nitric oxide (NO) participates in the regulation of many cell functions in the CNS, including modulation of ion channel function by direct changes in the channel protein structure, modulating permeability or gating kinetics. The mechanisms by which NO donors modulate sodium currents are protein and tissue specific. The present paper concerns sodium currents in the neuroblastoma N1E-115 cell line, applying whole-cell voltage clamp methods. Sodium currents were characterized in terms of the sensitivity to NO donors and the hydrophilic thiol oxidizer thimerosal. Parameters defining steady-state inactivation and activation, removal of inactivation and the voltage dependence of inactivation, were determined before and after thimerosal application. The results concerning the application of thimerosal showed blockade of the resting state, hyperpolarizing shifts of m(infinity) and h(infinity) curves, change in the voltage sensitivity and slower inactivating kinetics, tau(hf) and tau(hs) being affected in the same manner. The present results provide clear evidence for redox modulation of the sodium channel population in N1E-115 cells. Our results showed that the membrane-permeable alkylating agent (NEM) does not inhibit current reduction determined by thimerosal. We have reasons to suspect that the sodium channel population in N1E-115 cells differs in the proposed consensus sequence for nitrosylation or thimerosal cysteine oxidation. 相似文献
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do Prado RF Lima CF Pontes HA Almeida JD Cabral LA Carvalho YR 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,104(5):e40-e44
The aim of this study was to report an unusual case of mucoepidermoid carcinoma (MEC) in a 39-year-old woman. The tumor showed a prominent population of clear and intermediate basal cells. Clear cells rarely predominate over other cell types. Such cases are called clear cell variant of MEC. The case also revealed a variable amount of calcified material in the tumor mass. Calcifications are rare in clear cell MEC. These structures were periodic acid-Schiff positive and diastase resistant, excluding glycogen origin. Immunohistochemistry was performed, and the epidermoid component was positive for cytokeratin (CK)7, CK13, CK14, and CK19. The mucous and clear cells presented mild staining for CK7. Cytokeratins 7, 13, and 19 stained luminal cells, and intermediate cells exhibited positivity for CK7, CK14, and vimentin. The origin of the calcifications is speculated to be the result of dystrophic calcification of the amorphous eosinophilic material secreted by intermediate basal cells. 相似文献
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Lumeng JC Appugliese D Cabral HJ Bradley RH Zuckerman B 《Archives of pediatrics & adolescent medicine》2006,160(1):25-31
OBJECTIVE: To determine if there is a relationship between parental perception of neighborhood safety and overweight at the age of 7 years. DESIGN: Cross-sectional analysis of the National Institute of Child Health and Human Development Study of Early Child Care and Youth Development. SETTING: Ten urban and rural US sites. PARTICIPANTS: A total of 768 children selected via conditional random sampling with complete data at follow-up. MAIN OUTCOME MEASURES: Parents reported demographics and perception of neighborhood safety by standardized questionnaire. Child overweight status was defined as a body mass index greater than or equal to the 95th percentile for age and sex from measured anthropometrics at the age of 7 years. The base model included relationship of the safety reporter to the child, sex, and baseline body mass index z score at the age of 4.5 years. Covariates tested included maternal marital status, education, and depressive symptoms; child race/ethnicity; participation in structured after-school activities; Home Observation for Measurement of the Environment total score; and neighborhood social cohesiveness. RESULTS: The sample was 85% white, and 10% of the children were overweight. Neighborhood safety ratings in the lowest quartile were independently associated with a higher risk of overweight at the age of 7 years compared with safety ratings in the highest quartile (adjusted odds ratio, 4.43; 95% confidence interval, 2.03-9.65). None of the candidate covariates altered the relationship between perception of neighborhood safety and child overweight status. CONCLUSIONS: Perception of the neighborhood as less safe was independently associated with an increased risk of overweight at the age of 7 years. Public health efforts may benefit from policies directed toward improving both actual and perceived neighborhood safety. 相似文献
57.
S E Kountakis C Y Chang W B Gormley F R Cabral 《Otolaryngology--head and neck surgery》2000,123(3):170-173
The migratory behavior of acquired cholesteatoma matrices (those arising from the tympanic membrane) has been described previously. This tissue is derived embryologically from the first branchial groove and represents the only migratory epithelium arising from the branchial groove system. If the matrix from a cerebellopontine angle (CPA) epidermoid tumor exhibits migratory behavior similar to that of acquired cholesteatomas, a first branchial groove site of origin for CPA epidermoids would be supported. Intradural CPA epidermoid cells were grown in alpha-minimum essential medium. The cultures were examined daily, and cell mass migration rates were measured. It was observed that intradural epidermoid tumor matrix harvested from the CPA exhibited migration in vitro. Its migratory properties were indistinguishable from those of acquired cholesteatomas, which are embryologically derived from the first branchial groove. These data support the theory that purely intradural epidermoids are derived from cells of the first branchial groove. 相似文献
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