Mucin profiles and potential for malignancy of human colorectal adenomatous polyps

The mucin histochemical and histologic features of 166 colorectal adenomatous polyps from 124 patients were studied. A majority of the polyps (62%) had a tubular growth pattern whereas 38% showed villous growth. Severe dysplasia was more frequently found in the latter group. A significant correlation (r = 0.27, P less than 0.001) was found between the severity of dysplasia and the size of the polyps. Moreover, the ratio between goblet and columnar cells was also found to decrease (P less than 0.0001) with the severity of dysplasia. Independent of the mucin stain used (periodic acid-Schiff, alcian blue, and high-iron diamine stains), mucin reactive cells were found to be negatively correlated (-0.17 less than r less than -0.44, P less than 0.01) with severity of dysplasia, especially in the tubular adenomas. These findings suggest that evaluation of mucin stain, related to dysplasia, may contribute to the assessment of premalignant and early malignant changes in adenomas of the colon.     

Genetic ablation of the t-SNARE SNAP-25 distinguishes mechanisms of neuroexocytosis.

Axon outgrowth during development and neurotransmitter release depends on exocytotic mechanisms, although what protein machinery is common to or differentiates these processes remains unclear. Here we show that the neural t-SNARE (target-membrane-associated-soluble N-ethylmaleimide fusion protein attachment protein (SNAP) receptor) SNAP-25 is not required for nerve growth or stimulus-independent neurotransmitter release, but is essential for evoked synaptic transmission at neuromuscular junctions and central synapses. These results demonstrate that the development of neurotransmission requires the recruitment of a specialized SNARE core complex to meet the demands of regulated exocytosis.     

Threshold for occluded formaldehyde patch test in formaldehyde-sensitive patients

Our purpose was to investigate the eliciting threshold concentration of formaldehyde in formaldehyde-sensitive individuals in the occluded and non-occluded patch teat and to evaluate the relationship in repeated open application test (ROAT) with a product containing a formaldehyde releaser. 20 formaldehyde-sensitive patients and a control group of 20 healthy volunteer were included in the study. Occluded and non-occluded patch tests with formaldehyde solutions form 25 to 10,000 ppm. and ROAT for I week with a leave-on cosmetic product containing on average 300 ppm formaldehyde. Were carried out simultaneously on each subject. In the occluded patch test. 1/2 of the 20 patients only reacted to 10,000 ppm formaldehyde. 9 reacted to 5,000 ppm. 3 reacted to 1.000 ppm. 2 reacted to 500 ppm and I reacted to 25 ppm. No definite positive reactions were observed in the non-occluded patch test or in the ROAT No positive reactions were observed in the control group to any of the test procedures. We concluded that the threshold concentration for occluded patch test to formaldehyde in formaldehyde-sensitive patients was 250 ppm. The threshold in occluded patch test corresponded to the degree of sensitivity Definite positive reactions in the ROAT were not seen, either indicating that they are unlikely to happen with the type of product used or that the exposure time was too short.     

Growth modulation of hepatocytes and rat liver epithelial cells (WB-F344) by 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD)

Modulation of DNA synthesis by 2,3,7,8-tetrachlorodi-benzo-p-dioxin(TCDD) was studied in primary cultures of hepatocytes and inrat liver epithelial cells (WB-F344) to develop models for studieson the interactions between the activated Ah receptor and cellulargrowth control. In hepatocytes TCDD either positively or negativelymodulated EGF-stimulated DNA synthesis. In the presence of ethlnylestradiol10^–12 M TCDD moderately increased EGF-stimulated DNA synthyesis(     

Raised intracranial pressure,the syndrome of inappropriate antidiuretic hormone secretion,and arginine vasopressin in tuberculous meningitis

Intracranial pressure (ICP) monitored shortly after admission over a period of 1 h in 31 children with tuberculous meningitis (TBM) was significantly higher (median 22.5 mm Hg, range 8.4–50.9 mmHg) in 19 children with laboratory evidence of the syndrome of inappropriate antidiuretic hormone secretion (SIADH) than in 12 children without such evidence (median 16.2 mmHg, range 5.8–42.5 mmHg; P = 0.027). Neither plasma nor cerebrospinal fluid arginine vasopressin (AVP) was related to ICP (r = 0.33 and 0.13 respectively). Mean arterial pressure (MAP) was measured in 23 children and a moderate correlation was found with plasma AVP (r = 0.62; P = 0.0019). In TBM, plasma AVP may be secreted as a response to raised ICP in an effort to raise MAP and maintain cerebral perfusion pressure. In this setting excess fluid may be inappropriately retained, leading to hyponatremia and hypo-osmolemia.     

Recall of medication during pregnancy: Validity and accuracy of an adjusted questionnaire

Objective — To study the validity and accuracy of an adjusted questionnaire on medical drug use during pregnancy eight years after the pregnancy. Methods — The ability of a questionnaire on medication during pregnancy to detect actual use (= sensitivity) was tested against information collected 8 years previously (in 1983–1984) from 473 women with high-risk pregnancies who delivered at the University Hospital Nijmegen, the Netherlands. Results — For separate drug groups, the sensitivity varied between 5% and 91%. The timing of use was recalled moderately well. Although specific questions on drug groups did improve the sensitivity as compared to an earlier questionnaire, the improvement was not enough to make the questionnaire valid. High maternal education, low birth weight, low gestational age and a low 5-min Apgar score were related to better recall. The sensitivity of the questionnaire depended on the behavioural score of the child, implying recall bias. Conclusion — Questionnaire data on drug use during pregnancy obtained eight years after delivery are not a valid source of information.     

Quantitative proton MR spectroscopic imaging of the human brain

Multislice proton MR spectroscopic images (SI) of the brain were quantitated, using the phantom replacement technique. In 16 normal volunteers, ranging in age from 5 to 74 years, average “whole brain” concentrations of choline (Cho), creatine (Cr), and N-acetylaspartate (NAA) were found to be 2.4 ± 0.4, 7.9 ± 1.3, and 11.8 ± 1.0 (mM, mean ± SD), respectively. These values are in good general agreement with those previously determined by single-voxel localization techniques. Cortical gray matter was found to have lower Cho and NAA levels, compared to those of white matter, corpus callosum, and basal ganglia. Cho was also found to increase significantly with age in several locations. Quantitative multislice proton SI is feasible in the clinical environment, and regional and age-dependent variations occur that must be accounted for when evaluating spectra from pathological conditions.     

A double or bilobar gallbladder as a cause of severe complications after (laparoscopic) cholecystectomy

A double or bilobar gallbladder is a rare congenital anomaly. If not recognized during preoperative evaluation or operation, it can cause severe complications. We describe two cases in which a second operation had to be performed because of the presence of a second or bilobar gallbladder that was not recognized in the preoperative evaluation and during (laparoscopic) cholecystectomy. The types of anomalies, the concomitant pathology, and treatment are discussed.     

Testosterone Enhances GABA and Taurine but not N-Methyl-D,L-Aspartate Stimulation of Gonadotropin Secretion in the Goldfish: Possible Sex Steroid Feedback Mechanisms

The effects of gonadal steroids on GABA-, taurine (TAU)- and N-methyl-D, L-aspartate (NMA)-induced gonadotropin-II (GTH-II) release were investigated in male and female goldfish in vivo. In sexually regressed goldfish (both sexes mixed), intraperitoneal implantation for 5 to 10 days with solid Silastic pellets containing testosterone (100 μg/g), oestradiol (100 μg/g) or progesterone (100 μg/g) was previously shown to elevate serum sex steroid levels to values comparable to those in sexually mature animals, and to potentiate gonadotropin-releasing hormone-stimulated GTH-II release. In the present study, testosterone but not oestradiol or progesterone enhanced the stimulatory effects of exogenous GABA (100 μg/g) on GTH-II release in vivo. TAU (1 mg/g) stimulated GTH-II release in sexually regressed mixed sex and sexually recrudescent male goldfish, and both testosterone and oestradiol implantation enhanced GTH-II release induced by TAU. The glutamate agonist NMA (25 to 50 μg/g) was also found to stimulate GTH-II release; however it was relatively less effective in elevating serum GTH-II levels than GABA and TAU, and its effects were not modulated by sex steroid treatments. Pretreatment of goldfish with α-methyl-p-tyrosine to deplete brain and pituitary catecholam-ines did not affect NMA action on GTH-II release. Our results indicate that GABA, TAU and NMA are involved in the neuroendocrine regulation of GTH-II release in goldfish, and support the idea that testosterone participates in the positive feedback regulation of pituitary gonadotropin release in a non-mammalian vertebrate by enhancing GABA- and TAU-stimulated GTH release in vivo.