Effect of streptozocin-induced diabetes on insulin-receptor tyrosine kinase activity in obese Zucker rats

We examined insulin binding, insulin-stimulated autophosphorylation, and phosphorylation of poly(Glu.Na,Tyr)4:1 by liver and skeletal muscle insulin receptor from lean, obese, and obese streptozocin-induced diabetic Zucker rats. Induction of diabetes with streptozocin (30 mg/kg) lowered the lasting insulin level from 11.4 to 3.8 ng/ml, which was not significantly greater than the lean control level. Autophosphorylation and tyrosine kinase activity of liver insulin receptors were increased 70-100% in the obese control group (relative to lean rats), but diabetes reversed this hyperresponsiveness to insulin. In muscle, obesity was associated with a 40-50% decrease in autophosphorylation and tyrosine kinase activity, which was also reversed in the diabetic state. Autophosphorylation and tyrosine kinase activity were significantly correlated in liver and muscle and were also correlated with fasting insulin levels. These data suggest that insulin-receptor tyrosine kinase activity is regulated differently in liver and muscle and that the abnormalities in kinase activity associated with the obese Zucker rat are at least partly secondary to hyperinsulinemia.     

Dilation of the ventriculus terminalis: sonographic findings.

A newborn term male infant was found to have the stigmata of VACTERL syndrome, including cervical and thoracic hemivertebra, partial sacral agenesis, 13 pairs of ribs, high imperforate anus with rectovesical fistula, and tracheoesophageal fistula with proximal esophageal atresia. No open spinal dysraphism or skin dimpling was seen. Ultrasonography of the spinal cord was performed to screen for occult anomalies. The examination revealed a lipoma of the filum terminalis and a low-lying conus medullaris at the L3-L4 level with a large central cystic structure in the terminal cord, which was continuous with the central canal (Fig. 1). This was thought to most likely represent a dilated ventriculus terminalis, and the diagnosis was confirmed on a subsequent MR image (Fig. 2). Fluid in the cyst followed cerebrospinal fluid signal in all sequences. We observed no abnormal signal in the adjacent parenchyma or enhancement associated with the cystic mass. A cranial ultrasonogram did not reveal any intracranial anomalies. The patient demonstrated no neurologic deficits in the lower extremities. Bowel and urinary continence was not assessable in this infant.     

Tooth wear and occlusal sounds. Comparative study of restorative and orthodontic indices. Preliminary report

A comparative study of dental arch forms was conducted according to their manifestation of relative tooth wear and occlusal sounds. Thirty-six subjects were grouped according to their dental treatment experience into one of five arch form categories. Significant differences in the severity of tooth wear were found between the five groups. Tooth sounds were also found to be related to the dental arch form, and thus dental treatment category.     

Immunoregulatory markers in rats carrying Dunning R3327 H, G, or MAT-LyLu prostatic adenocarcinoma variants

The Dunning R3327 tumor represents a system for studying prostate cancer in Copenhagen X Fischer rats. Animals bearing variant sublines (H, G, and MAT-LyLu) differing in growth rate, differentiation, hormone responsiveness, and metastatic ability were assayed for three immunological markers. Spleens were passed through a tissue sieve, and mononuclear cells were obtained by Ficoll-Hypaque centrifugation. These were assayed for leukocytic subsets using monoclonal antibodies. An adherent population was isolated and evaluated using thin-layer chromatography for conversion of radiolabeled arachidonic acid to E series prostaglandins. Finally, sera from these animals were assayed for levels of circulating immune complexes using polyethylene glycol precipitation. Data from 52 rats bearing the various tumors were obtained, correlated with subline aggressiveness, and compared to 15 controls. Each tumor group demonstrated significantly lower helper/suppressor T-cell ratios than controls, probably due to general tumor presence. In addition, the most aggressive R3327 MAT-LyLu variant had significantly increased prostaglandin E synthesis by adherent spleen cells compared to the H or G sublines and significantly increased levels of circulating immune complexes relative to the H subline. G subline values for both prostaglandin E and circulating immune complexes levels were intermediate, suggesting that these markers correlate better with tumor aggressiveness than helper/suppressor T-cell ratios.     

Rotational ablation of balloon angioplasty failures

In this series, we evaluated the use of rotational ablation in stenoses that were previously refractory to balloon angioplasty. Forty-one stenoses were treated; in 26, the balloon did not adequately expand within the lesion and in 15 the balloon could not be delivered to the stenosis. Rotational ablation was technically successful in 40 of 41 (97.6%) of the lesions attempted. Twenty-four patients have been followed (mean time = 9 +/- 5 months) and the restenosis rate was similar to that of balloon angioplasty. Rotational ablation appears well suited and may be the treatment of choice for heavily calcified, severely angulated, and diffusely diseased vessels.     

Correlation of manual dexterity and comprehension with oral hygiene and periodontal status in mentally handicapped adults

Although there is relatively little information concerning the oral health of handicapped adults there is increasing evidence to suggest that their oral condition, particularly periodontal health, is poor. The present investigation involved assessment of 382 handicapped patients attending four different Adult Training Centres in Birmingham. The caries status, oral hygiene, and periodontal conditions were evaluated and the Community Periodontal Index of Treatment Need (CPITN) was calculated. In order to assess the manual dexterity and the comprehension of the trainees a standard test was devised. This consisted of timing each participant in carrying out simple instructions to pick up and position certain common objects. The results indicated high levels of plaque, calculus, and bleeding with a mean CPITN of 7.43. The mean time taken for the manual dexterity and comprehension test was 23.9 seconds with a range from 10 to 80 seconds, S.E.+/- 1.33. This compares with results from 34 "normal" adults of a mean time of 8.2 seconds +/- 1.8 with a range of 6 to 12 seconds. There was no significant correlation between the Manual Dexterity and Comprehension scores and the periodontal indices in the handicapped adults.     

Megalencephaly in sudden infant death syndrome

The fresh brain weights of 79 infants with sudden infant death syndrome (SIDS) were tabulated and compared with expected "normal" brain weights. The series included 47 males and 32 females. Their ages ranged from 8 days to 16 months with a median of 2.5 months. The weights of all these brains were above the 50th percentile for age, and 64 of 79 brains (81%) were above the 95th percentile, including 15 (19%) at or above the 99.9th percentile. The ratio of the brain stem plus cerebellum weight to the whole brain weight of 93 formalin-fixed brains from victims of SIDS showed that the cerebrum was disproportionately heavier in most cases. No gross or microscopic evidence of cerebral edema was noted to account for the heavier weight. The significance of these findings is debatable. The increase in brain weight was less obvious in infants younger than 1 month of age but accelerated after that age. The brain weights of infants with SIDS may represent the really "normal" weights, since these patients were not known to be ill prior to death. If the brain weights of SIDS infants are really heavier than "normal," the possibility must be considered that disproportionately rapid growth of the brain during early infancy may be detrimental to the neural control of the cardiorespiratory system.     

Transrectal fine-needle aspiration and truecut needle biopsy of the prostate: a blinded comparison of accuracy

Transrectal needle aspiration biopsy and core biopsy of the prostate were performed simultaneously on 88 men with prostatic nodules. Cytologic and histologic assessments were made in a blinded, independent fashion, and the results were compared. All patients with positive findings on aspiration also had positive findings on core biopsy, for a positive predictive value for aspiration of 100%. However, five negative and six "insufficient" results obtained by aspiration were positive on core biopsy, for a negative predictive value for aspiration of 88%. This experience support the use of needle aspiration as an initial diagnostic maneuver in the assessment of prostatic nodules.