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In mammalian cardiac tissue, the O2 consumption during mechanical rest is strikingly high. As this may relate to endothermy, the O2 consumption of resting atrial myocytes from an ectotherm, the rainbow trout, was examined. It was 1.46 ± 0.13, 1.96 ± 0.33, 4.34 ± 0.47, and 6.37 ± 0.79 nmol min^–1 mg protein^–1 at 5, 10, 15, and 20°C respectively. These values are about one fourth of the maximal O2 consumption recorded with 30 μM of the uncoupler dinitrophenol. Inhibition of mitochondrial ATP synthetase with 5 μg ml^–1 oligomycin reduced resting O2 consumption by 33 ± 9, 33 ± 1, and 24 ± 7% at 10, 15, and 20°C, respectively. Thus, only about one third of resting O2 consumption supports ATP synthesis, whereas the rest probably represents a futile proton cycle across the mitochondrial membrane. Thus, oligomycin-insensitive O2 consumption was not diminished by 30 μM ruthenium red, which inhibits mitochondrial Ca²⁺ uptake. About one half of the 30% of the O2 consumption coupled to ATP synthesis supports Na-K ATPase, inasmuch as 2 mM ouabain in the absence of extracellular Ca²⁺ reduced O2 consumption by about 15% at 10 and 15°C and somewhat less at 20°C. With 1.26 mM Ca²⁺, the reduction disappeared, probably due to the Na-Ca exchange. As examined at 15°C, changes in extracellular Ca²⁺, i.e., Ca²⁺ load, from 0 to 1.26 and 7 mM did not affect O2 consumption. Despite an apparent respiratory “overcapacity,” lactate measurements indicate that between 10 and 20% of the ATP synthesis in the resting cells is anaerobic. Inhibition by ouabain suggests that about 30% of the lactate production supports Na⁺-K⁺-ATPase. J. Exp. Zool. 283:501–509, 1999. © 1999 Wiley-Liss, Inc.

We have previously established an uremic rat model which is suitable for investigating the effect of various treatment modalities on the progression of renal osteodystrophy [1]. Four months subsequent to 5/6 nephrectomy, animals were treated three times a week for 3 months with either vehicle, 1,25-dihydroxyvitamin D3 [1,25(OH)2D3], 1,25(OH)2D3+24,25-dihydroxyvitamin D3 [24,25(OH)2D3], 1,25(OH)2D3+calcitonin (CT), or 1,25(OH)2D3+ 24,25(OH)2D3+CT. At termination of the study, clinical chemistry, chemical composition, and mechanical properties of femurs, calvarial parathyroid hormone (PTH)-elicited adenylate cyclase (AC), and phospholipase C (PL-C) activities, femoral cross-sectional area, and bone histomorphometry were analyzed. The main findings were that 1,25(OH)2D3±24,25(OH)2D3 treatment enhanced elasticity as well as time to fracture at the femoral metaphysis. CT potentiated the increase in elasticity obtained by 1,25(OH)2D3±24,25(OH)2D3 treatment. Only 24,25(OH)2D3 administration rectified the supernormal PTH-stimulated uremic bone AC, and only 1,25(OH)2D3 medication normalized the diminished CT-elicited AC. The obliterated uremic bone PTH-sensitive PL-C was fully normalized by all drug regimens. Femoral shaft inner zone diameter was enhanced by uremia, however, all drug treatments normalized it. Ditto effect was registered with either drug treatment on the subnormal outer and inner zone widths. Histomorphometrical analyses showed that 1,25(OH)2D3 administration reduced both eroded and osteoid surfaces. Most prominently, adjuvant 24,25(OH)2D3 or CT administration potentiated the beneficial effect of 1,25(OH)2D3 on fibrosis and osteomalacia. We assert that vitamin D3 treatment markedly reverses the development of renal osteodystrophy, and CT potentiates the effect of vitamin D3.

• Injury deaths in Ohio children aged 1 to 16 years account for less than 0.5% of all deaths in the state but 6% of all years of life lost before age 65 years. In this study, injury mortality rates were calculated by sex for three age groups (1 to 5, 6 to 11, and 12 to 16 years) and three population groups (metropolitan white, metropolitan nonwhite, and nonmetropolitan). The 15 metropolitan counties were those with a central city of at least a population of 50 000, containing 60% of the state's population. Fire is the leading cause of injury mortality for metropolitan children aged 1 to 5 years, while motor vehicle injuries and drowning are the leading causes for nonmetropolitan children in this age group. Fire is also the leading cause for metropolitan nonwhite children aged 6 to 11 years, while motor vehicle injuries are the leading cause for nonmetropolitan children, and pedestrian injuries are the leading cause for metropolitan white children. For nonmetropolitan and metropolitan white children aged 12 to 16 years, motor vehicle injuries are the leading cause, while for metropolitan nonwhite children homicide is the leading cause. Excess deaths for each cause were estimated by calculating the number of deaths expected for each age group if the rate experienced by the second-lowest population race group had applied to the whole population in that age group, and comparing this with the observed number. Using this approach, highest priority would be placed on prevention of motor vehicle deaths in 12- to 16-year-old nonmetropolitan and metropolitan white children, of fire deaths in metropolitan nonwhite children aged 1 to 11 years, and of drowning deaths in boys aged 12 to 16 years in all three population groups.(AJDC. 1990;144:79-82)

Human vascular cells are capable of stimulating granulopoiesis in agar culture of human bone marrow cells. This effect was obtained by including vein fragments in the culture or by using endothelial cells separated from the vein of human umbilical cords as feeder cells. Furthermore, the stimulatory capacity of conditioned medium obtained from cord veins was found to be highly active in comparison to that obtained from peripheral leukocytes. Endothelial cells within the bone marrow cavity are suggested as a local source of factors regulating granulopoiesis in humans in addition to the monocyte.

The elimination of ethanol, diazepam and oxazepam which are metabolised by different enzymes, has been studied for 30, 60, 90 and 120 min at 37, 27, 17 and 7d̀C in rat liver slice incubations. Ethanol elimination followed zero‐order kinetics at all temperatures, while the benzodiazepines consistently displayed first‐order kinetics. No sign of phasetransition was observed in the respective Arrhenius‐plots. Ethanol elimination was more temperature dependent than the elimination of diazepam, while the elimination of oxazepam was little influenced by temperature. This is shown by the temperature ratios (Q10) and energies of activation (Ea) of 1.76, 1.56, 1.24 and 40.5, 31.9, 15.2 for ethanol, diazepam and oxazepam, respectively. This means that ethanol, diazepam and oxazepam elimination was reduced by 25, 22 and 14%, respectively, for each 10d̀C of temperature reduction, which is considerably lower than the commonly observed 50% reduction of enzyme activity. We conclude that observations made for one drug on temperature dependent elimination may not apply to other drugs.

The changes in peripheral blood counts and number of colony forming cells (CFU-c) in the bone marrow after 131I treatment for thyroid cancer were followed in 24 patients. The median WBC declined to 78% and the median blood platelet count to 69% of the pretreatment values after 4 treatments. In 4 patients a moderate pancytopenia developed and in 1 patient additionally treated with chemotherapy and preleukaemia was suspected. In 19 bone marrow samples obtained from 13 patients no difference in number of CFU-c could be found related to cumulated 131I activities given to those patients. In 5 of 7 patients examined between the 9th and the 19th day after a treatment the number of CFU-c had declined by 50% or more. It is concluded that radioiodine exerts a protracted suppressive effect on the bone marrow which is seldom severe. Agar culture of bone marrow cells with counting of CFU-c was not found to be more sensitive than the peripheral blood counts in predicting bone marrow damage and cannot be recommended for routine use.

British and American obstetric societies recommend that elective cesarean section (ECS) be scheduled after 39 weeks’ gestation to reduce the incidence of neonatal death or adverse events. This multicenter, open-label, randomized controlled trial was undertaken at 7 Danish hospitals to investigate the risk of neonatal intensive care unit (NICU) admission associated with ECS scheduled before versus after 390weeks’ gestation.

A randomized study of abdominal fascial closure using interrupted polyglyconate and polyglycolic acid sutures after laparotomy was carried out in 204 consecutive patients with suspected impaired wound healing. There were no statistically significant differences between the two sutures with regard to the development of fascial disruption and incisional hernia. Wound infection demanding surgical intervention was found in 7 per cent of patients with polyglyconate sutures and in 16 per cent of those with polyglycolic acid sutures (P0·04). Monofilament polyglyconate suture does not reduce the incidence of fascial disruption and incisional hernia after laparotomy in patients with suspected impaired wound healing but the incidence of wound infection may be reduced compared with that of multifilament polyglycolic acid suture.

Presents guide to preventing workplace injuries in the construction industry. Impact of workplace injuries on employees and employers; Actions that employers should take to prevent the occurrence of injuries; Total mean cost for a workplace injury.