Training decreases muscle glycogen turnover during exercise

Bioelectric activity of a nervous tissue and its synchronization with formatting epileptiform bursts are simulated by a coupled map lattice. The functional units of the map located in the lattice sites represent neural masses which consist of current sources and sinks. The sources lead to depolarization of neurons, and sinks provide hyperpolarization. The map describes a single variable--the bioelectric potential. This potential is created by the interplay of all current sources and sinks in the neural masses. The neural masses are diffusively coupled with each other both by electronic influence and synaptic coupling. Both mechanisms mentioned are suggested to be essential for the formation of synchronous bursts. The transition from chaotic activity to bursts was studied.     

A case-control study of dietary intake and other lifestyle risk factors for hyperplastic polyps

BACKGROUND & AIMS: Despite the high prevalence of the hyperplastic polyp, little is known about its etiology. The aim of this study was to assess the relationship between diet and other lifestyle factors and the presence of colorectal hyperplastic polyps. METHODS: Information on diet and other known or suspected risk factors for colorectal cancer or adenoma was collected among 81 subjects with hyperplastic polyps and 480 controls. RESULTS: The multivariate-adjusted odds ratio (OR) for hyperplastic polyps for individuals in the upper vs. the lower quartile was 0.30 (95% confidence interval [CI], 0.10-0.88) for dietary fiber, 0.32 (95% CI, 0.11-0.96) for dietary calcium, 0.90 (95% CI, 0.27-2.95) for total fat, and 2.02 (95% CI, 1.05-3.91) for alcohol consumption. Compared with individuals in the lower category, those in the upper category of body mass index had a higher risk for hyperplastic polyps (OR, 4.50; 95% CI, 1.84-10.97). Cigarette smoking was associated with a higher risk (OR, 1.97; 95% CI, 1.02-3.81 for > 20 pack-years vs. never), whereas an inverse association was seen for use of aspirin and other nonsteroidal anti-inflammatory drugs (OR, 0.29; 95% CI, 0.12-0.67 for once per day or more vs. never). CONCLUSIONS: Hyperplastic polyps share common lifestyle risk factors with colorectal adenomas and carcinomas.     

ANP gene expression in rat hearts during hypoxia

The relationships between muscle capillarization, estimated O2 diffusion distance from capillary to mitochondria, and O2 uptake (VO2) kinetics were studied in 11 young (mean age, 25.9 yr) and 9 old (mean age, 66.0 yr) adults. VO2 kinetics were determined by calculating the time constants (tau) for the phase 2 VO2 adjustment to and recovery from the average of 12 repeats of a 6-min, moderate-intensity plantar flexion exercise. Muscle capillarization was determined from cross sections of biopsy material taken from lateral gastrocnemius. Young and old groups had similar VO2 kinetics (tau VO2-on = 44 vs. 48 s; tau VO2-off = 33 vs. 44 s, for young and old, respectively), muscle capillarization, and estimated O2 diffusion distances. Muscle capillarization, expressed as capillary density or average number of capillary contacts per fiber/average fiber area, and the estimates of diffusion distance were significantly correlated to VO2-off kinetics in the young (r = -0.68 to -0.83; P < 0.05). We conclude that 1) capillarization and VO2 kinetics during exercise of a muscle group accustomed to everyday activity (e.g., walking) are well maintained in old individuals, and 2) in the young, recovery of VO2 after exercise is faster, with a greater capillary supply over a given muscle fiber area or shorter O2 diffusion distances.     

Prediction of the outcome of transplantation in man by platelet adherence in donor liver allografts. Evidence of the importance of prepreservation injury

We examined platelet adhesion in thirty human donor livers to determine if the degree of platelet adhesion could predict outcome of transplantation. Wedge liver biopsies were taken at the start of the donor operation (biopsy 1) and 1 hr after reperfusion in the recipient (biopsy 2). Biopsies were stained with a monoclonal antibody against platelet glycoprotein Ib and graded for platelet adhesion. Hematoxylin and eosin-stained sections were examined for polymorphonuclear leukocyte adhesion and necrosis. Platelet adhesion was much more frequent and extensive than expected in biopsy 1. Nine of 30 biopsies showed moderate or high-grade platelet adhesion. Thus in this study endothelial cell damage was present in about one-third of donors before the donor operation. The injury was not detectable by routine microscopic or clinical examination or biochemical tests. The degree of platelet adhesion in biopsy 1 predicted development of PMN adhesion and necrosis in biopsy 2 and postoperative transaminase concentrations and prothrombin times in recipients. During preservation and implantation some livers converted from low to either moderate or high grades of platelet adhesion. The grade of platelet adhesion in biopsy 2 predicted postoperative outcome as measured by transaminase and PT levels. Patients whose platelet grade converted to a higher level during preservation and implantation did not do as well as patients who remained at a low adhesion grade. These findings strongly suggest that the degree of platelet adhesion is an important determinant in assessing outcome and may provide a means of measuring the status of liver allografts prior to transplantation.     

Halothane-associated enhancement of the secondary immune response to sheep erythrocytes in mice: cell transfer studies

The effect of halothane anesthesia on the humoral immune response to sheep red blood cells was studied in mice immunized twice, with a 15-day interval. On both occasions, mice were exposed to 1.5% halothane for 40 min immediately after sensitization. Halothane reexposure resulted in increased numbers of IgG-secreting cells (IgG-SC) as well as circulating 7S-serum agglutinins. To examine further whether this effect could be obtained in syngeneic recipients, adoptive transfer experiments employing spleen cells were performed. While mice receiving cells from unimmunized and anesthetized donors displayed significantly higher levels of IgG-SC, recipients of cells from normal, immunized and immunized-anesthetized donors showed a depressed response when compared to control counterparts. Besides the possibility of an enhancing effect of halothane reexposure on the humoral response, this procedure may counteract normal physiological immunoregulatory processes during the generation of the immune response.     

Effect of aging on microleakage of restorative systems

This study evaluated the sealing properties of AP.H/Prisma Universal Bond 3, Z100/Scotchbond MultiPurpose, AP.H/Imperva Bond, Charisma/Denthesive, Bisfil M/All-Bond 2, resin composite/dentin adhesive systems and Fuji II LC light-cured glass ionomer, in Class V preparations following 6 months of storage in a 37 degrees C water bath. The Class V preparations extended just beyond the cemento-enamel junction of extracted human molars. The restored teeth were placed in 37 degrees C water for 24 hours and then thermally stressed for 100 temperature cycles. Half of the specimens were tested for microleakage at this time. The other specimens were returned to water storage and thermally stressed every 30 days during the following 6 months and then assessed for microleakage by dye penetration. AP.H/Imperva Bond, Z100/Scotchbond Multi-Purpose and Fuji II LC were not affected by the storage, while AP.H/Prisma Universal Bond 3, Charisma/Denthesive and Bisfil M/All-Bond 2 revealed some increase in microleakage at the dentin/cememtum margin.     

Fundus laser coagulation using a video system of scanning laser ophthalmoscope

We modified a scanning laser ophthalmoscope for simultaneous photocoagulation of the retina and video recording. Using a diode laser (810 nm wavelength), we produced fundus lesions that scarred within 14 days.