Persistent acute renal failure with renal artery stenosis: cure following reconstructive arterial operation

A case of acute renal failure is reported in which renal function returned after surgical correction of renal artery stenosis to the sole functioning kidney. Acute renal failure associated with renal vascular lesions is reviewed. Although often clinically apparent vascular obstruction may be asymptomatic and should be considered in cases of prolonged acute renal failure.     

Factors affecting serum oxytetracycline levels in beef calves

Fifteen Aberdeen Angus steers, 295-364 kg, were dosed with either 4.4 or 11 mg of oxytetracycline hydrochloride/kg im. The antimicrobial activity of the serum was determined periodically, and the resulting data were treated statistically to determine the sources of variation. Variance in serum levels of oxytetracycline activity was attributed to dose, time of bleeding, order of dosing, animal, and assay. The total variance component was proportionately greater for the 11-mg/kg dose than for the 4.4-mg/kg dose. Animal variance increased with the higher dose level of oxytetracycline. The influence of dose on serum level was tested by applying a t test to the mean serum levels and their standard deviations at each bleeding time. The 4.4- and 11-mg/kg serum levels were significantly different (p less than 0.01) at all bleeding times. The 4.4-mg/kg serum levels mutliplied by 2.5 were not significantly different (p less than 0.05) from the 11-mg/kg serum levels at all bleeding times.     

Significance of adrenal hormones in brain energy metabolism

Intensity of glycolysis was studied under conditions of immobilization stress and adrenalectomy as well as with administration of adrenaline and hydrocortisone. The processes of aerobic glycolysis, activity of enzymes of the tricarboxylic acid cycle and mitochondria respiratory chain, content of total, free and protein-bound glycogen, glucose-I-phosphate, glucose-6-phosphate, pyruvate, alpha-ketoglutarate, cytrate and macroergs in the brain are shown to depend on the level of adrenal hormones producing a multilateral effect on a series of energy metabolism links.     

Effect of vitamin A supplementation on diarrhoea and acute lower-respiratory-tract infections in young children in Brazil

A beneficial effect of periodic vitamin A supplementation on childhood mortality has been demonstrated, but the effect on morbidity is less clear. We investigated the effect of vitamin A supplementation on diarrhoea and acute lower-respiratory-tract infections (ALRI) in children from northeastern Brazil in a randomised, double-blind, placebo-controlled community trial. 1240 children aged 6-48 months were assigned vitamin A or placebo every 4 months for 1 year. They were followed up at home three times a week, and data about the occurrence and severity of diarrhoea and ALRI were collected. Any child with cough and respiratory rate above 40 breaths per min was visited by a paediatrician. The overall incidence of diarrhoea episodes was significantly lower in the vitamin-A-supplemented group than in the placebo group (18.42 vs 19.58 x 10(-3) child-days; rate ratio 0.94 [95% Cl 0.90-0.98]). The benefit of supplementation was greater as regards severe episodes of diarrhoea; the incidence was 20% lower in the vitamin A group than in the placebo group (rate ratio 0.80 [0.65-0.98]). With the standard definition of diarrhoea (> or = 3 liquid or semi-liquid stools in 24 h) the effect of vitamin A on mean daily prevalence did not reach significance, but as the definition of diarrhoea was made more stringent (increasing number of stools per day), a significant benefit became apparent, reaching for diarrhoea with 6 or more liquid or semi-liquid stools in 24 h a 23% lower prevalence. We found no effect of vitamin A supplementation on the incidence of ALRI. The reduction in severity of diarrhoea may be the most important factor in the lowering of mortality by vitamin A supplementation.     

Is local biotransformation the key to understanding the pharmacological activity of salicylates and gold drugs?

It is suggested that some drugs may be converted by inflammatory cells to yield active species. The transformation may be non-enzymatic, although being driven by the enzymatic production of highly reactive species which are normal products of activated leukocytes, such as singlet oxygen, hydrogen peroxide, hypochlorite, hydroxyl radical and nitric oxide. Drugs which may be transformed in this fashion are the anti-rheumatic gold complexes which may be converted either to aurocyanide or to Au(III) complexes by myeloperoxidase in polymorphonuclear leukocytes. Salicylate may also be activated by its oxidation to dihydroxybenzoates although evidence for its transformation is weaker than for the gold complexes.     

Bcl-2 overexpression blocks activation of the death protease CPP32/Yama/apopain

Females who are affected by fragile X syndrome (FXS) can have significant physical, neuropsychological and emotional involvement. This study was designed to explore the relationships between these three domains and to learn how the degree of involvement in each of these phenotypic areas relates to molecular parameters including CGG repeat length and activation ratio (the proportion of normal FMR1 alleles on the active X chromosome). Three groups of females were studied: 35 women who grew up in a fragile X family but do not carry an FMR1 mutation, 92 women with a premutation, and 29 women with a full mutation. Correlations between neurocognitive, physical and emotional traits were calculated for each of the three groups. Within the full mutation group significant correlations were seen between schizotypal traits and full scale IQ. The Lie scale was significantly correlated with the physical findings index. The activation ratio correlated significantly with the measure of executive function (r = .50, P = .01). There was a trend toward correlations of activation ratio with the physical index score, outer ear prominence and IQ. CGG repeat number significantly correlated only with the physical index (r = .44, P = .01). Thus, activation ratio may be the more pertinent molecular parameter in full mutation women in determining the degree of cognitive and physical phenotypic involvement.     

Eucapnic hypoxia lowers human cold thermoregulatory response thresholds and accelerates core cooling

Hypoxia lowers the basic thermoregulatory responses of animals and humans. In cold-exposed animals, hypoxia increases core temperature (Tco) cooling rate and suppresses shivering thermogenesis. In humans, the experimental effects of hypoxia on thermoregulation are equivocal. Also, the effect of hypoxia has not been separated from that of hypocapnia consequent to hypoxic hyperventilation. To determine the isolated effects of hypoxia on warm and cold thermoregulatory responses and core cooling during mild cold stress, we examined the Tco thresholds for sweating, vasoconstriction, and shivering as well as the core cooling rates of eight subjects immersed in 28 degrees C water under eucapnic conditions. On 2 separate days, subjects exercised on an underwater cycle ergometer to elevate Tco above the sweating threshold. They then rested and cooled until they shivered vigorously. Subjects inspired humidified room air during the control trial. For the eucapnic hypoxia trial, they inspired 12% O2-balance N2 with CO2 added to maintain eucapnia. Eucapnic hypoxia lowered the Tco thresholds for vasoconstriction and shivering by 0.14 and 0.19 degrees C, respectively, and increased core cooling rate by 33% (1.83 vs. 1.38 degrees C/h). These results demonstrate that eucapnic hypoxia enhances the core cooling rate in humans during mild cold stress. This may be attributed in part to a delay in the onset of vasoconstriction and shivering as well as increased respiratory heat loss during hypoxic hyperventilation.