Evaluation of boys with marked breast development at puberty

OBJECTIVE: The purpose of this study was to investigate the efficiency of second-trimester maternal serum screening for Down's syndrome and open neural tube defects using alpha-fetoprotein and free beta-human chorionic gonadotropin as serum markers. METHODS: 3, 188 women underwent testing between 14th and 22nd week of pregnancy. Of all tested patients, 25.4% were >/=35 years old. A cut-off risk of >/=1:250 for Down's syndrome and MS-AFP >/=2.0 MoM for open neural tube defect were considered screen-positive. RESULTS: The detection rate for Down's syndrome was 77.8% (7/9) with 8.2% screen-positive rate (7.9% false-positive rate). When evaluated separately, in patients younger than 35 and in those >/=35 years old, the screen-positive rates were 3.1 and 23.3%, respectively. A total of 52 (1.6%) were found screen-positive for open neural tube defect; 2 cases of encephalocela and 1 case of gastroschisis were confirmed prenatally. CONCLUSION: The respectable number of cases with trisomy 21 identified in this study confirms that routine mid-trimester screening for Down's syndrome including MS-AFP, free beta-hCG and maternal age is useful in identifying pregnancies at increased risk.     

Water-leaching rates of halides from polymers

Water-leaching experiments of halides from polymers were carried out in batch and continuous systems. The effects of flow rate, temperature, and salt content on the leaching kinetics were investigated. Different thermoplastic polymers were used as the salt carrier, and the release kinetics from them was established. NaCl, NaBr, and NaI were leached out completely from nylons, while NaF could only be partially removed. Release mechanisms involving diffusion, capillary flow, and fracturing were described based upon the leaching kinetics and porosity distribution in the resulting foams.     

The structure of bovine periodontal ligament with special reference to the epithelial cell rests

The aim of this study was to determine the structure of the bovine periodontal ligament, with special reference to epithelial cell rests (ECR) and their cytokeratin content. Periodontal ligament was obtained from bovine molar teeth and studied at both the light microscopic and electron microscopic levels. Cytokeratin content was determined using immunohistochemistry against a number of cytokeratin antibodies and specificity tested against bovine and human oral mucosa. Collagen fibril diameters and the area of a fiber bundle occupied by collagen were determined using a digital planimeter with a digitizing tablet. The majority of periodontal fibroblasts possessed considerable quantities of roughened endoplasmic reticulum, indicating rapid synthesis and secretion of collagen, but no intracellular collagen profiles were present. Endothelial cells showed Weibel-Palade bodies. Collagen fibril diameters showed a unimodal distribution with a mean collagen fibril diameter of 55.3 nm. The mean percentage area of the extracellular matrix occupied by collagen was 42%. Structurally, ECR were unusual in exhibiting large numbers of microvilli and conspicuous amounts of cytokeratin filaments. Bovine ECR showed a positive reaction to the pancytokeratin MNF116 (which reacts with the cytokeratins 5, 6, 8, 17, and probably 19), to PCK-26 (which reacts with the type II cytokeratins 1, 5, 6, and 8) and to cytokeratin 13. There was no reaction for cytokeratins 1, 4, 10, 11 and 18. Structurally, bovine periodontal ligament showed features common to other species. However, ECR in terms of both structure and cytokeratin content showed features indicative of important species differences which may have relevance when considering the etiology of radicular cysts.     

Carnitine deficiency in inborn errors of metabolism

Several conditions, considered as inborn errors of metabolism, involve severe deficiencies in carnitine in both plasma and muscle. In the absence of evidence suggesting primary carnitine deficiency due to a biosynthetic enzymatic defect in the liver, the various diseases with carnitine deficiency are related to genetic defects in organic acid metabolism leading to blocked mitochondrial beta oxidation. We describe a 4.5-year-old boy and 2 female infants with glutaric aciduria type I, isovaleric acidemia, and long-chain acid dehydrogenase deficiency, in whom severe carnitine deficiency was apparent. In all 3, long-term carnitine treatment proved to be vital and eliminated most of the symptoms.     

FFT processing of randomly sampled harmonic signals

The influence of random instabilities in the sampling instants on spectral estimation by the fast Fourier transform (FFT) of harmonic, stochastic processes is considered. The degradation due to the deviation from a uniform sampling is presented by explicit formulas. This degradation, a decrease of the desired signal and an increase of the sidelobe noise, is expressed in terms of the characteristic function of the jitter's distribution     

The effect of epidermal growth factor in human granulosa cells varies with follicle size

The distribution of the zot gene that encodes the zonula occludens toxin, a newly described toxin of Vibrio cholerae, among clinical, environmental and food isolates of V. cholerae 01 and non-01 was investigated. Both the zot gene and the ctx gene that encode cholera toxin were found in 247 of 257 clinical strains and 62 of 415 environmental or food isolates of V. cholerae 01. The zot gene, but not the ctx gene was found in 37 strains (one clinical strain and 36 environmental or food isolates). In addition, two of 31 clinical strains and six of 98 environmental or food isolates of V. cholerae' non-01 possessed both the zot gene and the ctx gene. These results demonstrated the predominantly concurrent occurrence of the zot gene and ctx genes among strains of V. cholerae 01 which suggests a possible synergistic role of ZOT in the causation of acute dehydrating diarrhea produced by V. cholerae 01.