Biomedical subjects
Publications and source records attributed to J Oliver.
An extremely simple spectrophotometric method for measuring biliary ioglycamide (meglumine ioglycamate) concentration is described. It was validated by a radioactive technique.
When five patients with varying degrees of hepatic impairment and a T-tube in situ were given intravenous ioglycamide at a rate of 2 mg/kg/min for two hours the mean biliary excretion in the first two hours was only 3.2% of the administered dose. In contrast, in five T-tube patients with relatively normal liver function the mean biliary excretion over the same time interval was 20.6%. The mean plasma concentration of ioglycamide achieved at the end of a two-hour intravenous infusion at 2 mg/kg/min was 1427 +/- 187 microgram/ml in six anicteric patients and 1262 +/- 82 in six jaundiced patients. Despite these very similar plasma levels the 24-hour urinary excretion of ioglycamide was 42.3 +/- 3.8% of the administered dose in the patients with jaundice compared with only 18.1 +/- 2.4% in the anicteric group. These differences probably reflect the fact that the percentage of unbound contrast agent in the plasma of the jaundiced group (11.9 +/- 1.9%) was significantly higher than that of the anicteric group (6.4 +/- 0.9%). It is suggested that bilirubin and possibly other substances in the plasma are competing with ioglycamide for binding sites on albumin. These factors need to be borne in mind when performing intravenous cholangiograms on jaundiced patients.
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Hooded Lister rats were sensitized to DNP-ovalbumin. These rats showed a significant alteration in respiratory pattern when challenged with DNP-ovalbumin aerosol. The respiratory response was not produced by challenging sensitized rats with intragastric DNP-ovalbumin. The magnitude of the respiratory response did not correlate with the specific IgE concentration in the serum. A similar pattern of respiratory response was inducible in unsensitized rats by intravenous administration of IgE-rich sera.
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Brazilian squirrel monkey kidneys removed before and after administration of parathormone were studied by microdissection, polarizing microscopy, alizarin red and von Kossa's stains, and microchemical analysis. Intralumenal crystalline-matrix masses were observed in both groups but were increased in frequency after parathormone administration. Specific staining showed the presence of calcium and phosphorus, and specific chemical tests suggested the presence of uric acid or urate salts. Refractile alizarin red positive droplets were observed in the tubular cells of the pars convoluta in parathormone-treated animals. Urinary stone formation in these animals is unique in that the location and types of stones produced are similar to that seen in man. The squirrel monkey is a good experimental model to study renal stone disease and further studies of its etiology, structure, composition, and means of control should be performed.
Individual quarter milk samples were taken from 719 cows in 7 dairy herds and examined for mastitis-causing pathogens. Analyses were made to ascertain the prevalence of mastitis infection when the results from a single quarter were compared with those from all 4 quarters. There was a very close similarity between the 2 methods of assessment. When the number of samples is limited, sampling of a single quarter instead of all 4 quarters permits more cows to be examined.
The effects of altered acid-base balance on the production of urea and the metabolism of glutamine were investigated in the isolated perfused liver and hindquarter of the rat. In the isolated perfused rat liver, lowering of perfusate pH without altering bicarbonate concentration significantly reduced urea production and increased net glutamine synthesis, although the converse did not obtain. In the isolated perfused rat hindquarter when perfusate pH and bicarbonate were simultaneously reduced glutamine synthesis was significantly increased. The combined hepatic and muscle increase in glutamine synthesis accounted for 89% of the decrease in hepatic urea synthesis under these experimental conditions. These changes in nitrogen metabolism are interpreted in terms of adaptations which offset the initial alterations in hydrogen ion homeostasis.
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Radioluminous paint (R.L.P.), 0.029 cd/m2, was implanted in various parts of the hypothalamicpreoptic system. Small pellets, 0.6 mm in diameter, 0.2 mm thick, were stereotaxically located either in the basal medial hypothalamus or in the suprachiasmatic-preoptic area. Basal hypothalamic illumination through R.L.P. resulted in a strong testicular growth. No testis enlargement was induced after anterior implant or R.L.P. Results are discussed in terms of hypothalamic deep photoreceptors and of functional roles devoted to basal hypothalamic and preoptic regions with respect to the photosexual reflex.
Multiple unit activity (MUA) was obtained from gonadotropic areas of the hypothalamus in quail. Pellets of radioluminous paint (RLP) were implanted unilaterally either in the nucleus tuberis or in the n. posterior medialis hypothalami. Control data were obtained from birds receiving nonluminous material (RP). Spontaneous MUA was decreased by 25% in gonadotropic arease in RLP-treated quail. Direct permanent photostimulation of hypothalamic neuronal population was not as effective in decreasing MUA as environmental photostimulation (50%). Activation in firing rates, which was constant in nonphotostimulated intact birds in response to repetitive flash-light stimulations, was completely suppressed after implantation of RLP.
Small bilateral lesions of the preoptic and anterior hypothalamic regions completely suppressed the light-induced testicular growth in quail. Photic stimulation was selectively applied to this region using a small pellet of radioluminous paint (RLP). This local photostimulation induced no testicular growth in short day quail. On the contrary, testes were markedly enlarged after RLP was implanted in the tuberal or in the dorsal area of the infundibular complex of short day quail. This response was as large as in controls reared under 18L-6D. It is therefore confirmed that neuronal populations located in the infundibular complex are directly photosensible. No direct photosensitivity was observed in the preoptic and anterior hypothalamic regions and it is suggested that these areas can serve as a relay for retinal information.
Mice and sheep with circulating antibody to dinitrophenol (Dnp) retained injected 3H-epsilon-Dnp-lysine in their circulation for three and seven days respectively. In normal mice and sheep the 1 h post injection counts of 3H/g of kidney were higher than those per ml of plasma. In immune mice, plasma 3H counts were always higher than kidney counts, whereas at 1 h in immune sheep, plasma and kidney counts were similar. Liver, spleen and lung counts were also made in some experiments. Increased 3h counts could be demonstrated in mice treated passively with sheep anti-Dnp serum and then given 3h-epsilon-Dnp-lysine. The fast gamma-globulin of sheep antiserum is mainly responsible for retention of hapten in mouse plasma.
In the thalamic pigeon, neurogenic stimuli were still effective in promoting the adreno-cortical activation. The magnitude of the response was as important as in intact birds and was also similar to that obtained after anterior lateral deafferentation of the hypothalamus. Photically induced testis growth was quite normal in hemispherectomized quail. It appears therefore that in birds two kinds of neuroendocrine responses can be induced without any telencephalic participation.
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