The role of retinol-binding protein in protein-calorie malnutrition

Plasma RBP is decreased to $\text{1.62 mg ± 0.71}\text{100 ml}$, or 31.1% of normal, in the acute stage of kwashiorkor. RBP doubles its plasma level after 1 wk and triples after 2 wk of appropriate refeeding. The return to normal of RPB runs in close parallel with prealbumin (PA), implying that both components remain bound by 1:1 molar ratio in the PA-RBP complex. Low values recorded on admission for RBP seem to be the result of reduced liver biosynthesis. On the other hand, a high correlation persists between RBP and retinol plasma level along the successive steps of clinical recovery, suggesting that RBP acts as the limiting factor for retinol transport.     

Nembutal treatment of the VMH (rat): Effects on feeding and sexual behaviour

In male rats two brain cannulae were implanted bilaterally and directed to an area just dorsal of the ventromedial hypothalamic nucleus. The behaviour of these animals was observed before and after the injection through these cannulae of either 1 μl saline or 1 μl Nembutal. Injections were performed under three behavioural conditions: (1) animal alone in cage with food, (2) animal in the presence of an oestrous female and (3) animal in cage with food and oestrous female. Following the Nembutal injection, sniffing and feeding are disinhibited temporarily in condition 1, whereas in condition 3 only sniffing, but not feeding, is disinhibited. In conditions 2 and 3 male sexual behaviour is not influenced by the Nembutal except for an increase of sniffing at the female.It is concluded that a temporary elimination of the VMH leads to a disinhibition of feeding only if the external conditions are favourable for feeding. The same elimination of the VMH does not influence the occurrence of male sexual behaviour under the conditions used in these experiments.     

Short-term toxicity of strontium chloride in rats

A range-finding experiment with strontium chloride hexahydrate (0, 3, 30, 300 and 3000 ppm in the diet) and subsequently a 90-day test with the same compound at dose levels of 0, 75, 300, 1200 and 4800 ppm in a semi-purified diet was carried out with SPF-derived Wistar-rats. The diet contained adequate levels of Ca, Mg, P and Vit.D₃. Growth, food intake, behavior and mortality were measured, extensive haematology and clinical biochemistry carried out, organ weights determined, X-ray photographs of the bones taken and complete histopathological examination was performed. In addition Sr-content of blood, bone and muscles was determined. Thyroid weights were significantly increased in the males of the 1200 and 4800 ppm group. Histological evidence for increased thyroid activity was noticed in the males of the 4800 ppm group. Pituitary weights were significantly decreased in the females of the 300 ppm and 4800 ppm group, but not of the 1200 ppm group. A histologically confirmed glycogen depletion of the liver was noted biochemically in the highest dose group (4800 ppm).Sr-content in bone was increased at all dose levels having a constant level from 4 weeks onwards, thus indicating that a no effect level cannot be established. If the increased Sr-concentration in the bone can be considered a non-toxic effect, the non-toxic effect level appears to be 300 ppm.     

Total prosthetic replacement of atrioventricular valves in the dog: Part I. Development of a free-floating cone valve for the right atrioventricular ostium

A free-floating cone valve to be used as a prosthesis for the tricuspid valve of the heart is described. It consists of a stainless steel flat cage with a Lucite cone inside. The experience and reasoning that led to its construction are presented and the results obtained with it in a series of 32 dogs are given.     

The determination of ammonium in kjeldahl digests using the gas-sensing ammonia electrode. Comparison of the direct method with the known-addition method

The efficacy of the ammonia electrode for analysis of the nitrogen content of a large series of Kjeldahl digests was investigated. By using this electrode, two methods for the measurement of ammonium concentrations were compared, the direct method and the known-addition method.

When the direct method was used, a marked shift in the electrode potential occurred within a few hours, causing errors of 9–17% in the results. When the ammonium concentrations were calculated from the difference in electrode potential before and after addition of a known amount of an ammonium standard solution (known-addition method), it was possible to carry out reproducible measurements and the shift in the electrode potential did not influence the results. In two series of identical samples the coefficient of variation was respectively 1.45% and 0.80%.