Effect of lactation on the metabolism of sheep adipose tissue

The rates of incorporation of 14C glucose and 14C acetate into triglycerides by slices of omental adipose tissue were much lower in tissues from sheep in early lactation than in tissues from dry, non-pregnant sheep. The rates of oxidation of both substrates were also much lower in early lactation but increased again in late lactation. There was an increase in the incorporation of 14C acetate into triglycerides in late lactation and a further increase after the lambs were weaned. Lipoprotein lipase activity was lower in omental adipose tissue from lactating sheep than in tissue from dry, non-pregnant sheep. There were marked increases in the concentrations of nonesterified fatty acids in plasma and in adipose tissue during early lactation. The rate of release of glycerol by adipocytes in vitro also increased during lactation. These results suggest that there was a change from lipid deposition to lipid mobilisation during lactation.

Inhibition of synaptosomal [3H]noradrenaline uptake by beta-adrenoceptor blocking drugs: influence of lipophilicity

Ten beta-adrenoceptor blocking drugs varying in lipophilicity and beta-adrenoceptor blocking potency were examined for inhibitory effects on synaptosomal [3H]noradrenaline uptake. All compounds produced a concentration-dependent inhibition of noradrenaline uptake, but were at least one order of magnitude less potent than desmethylimipramine and cocaine. The order of potency was pronethalol greater than propranolol greater than betaxolol greater than alprenolol greater than oxprenolol greater than practolol greater than metoprolol greater than acebutolol greater than sotalol greater than atenolol, with IC50 values ranging from 4.0 X 10(-6) to 2.2 X 10(-3) M. Uptake inhibition was unrelated to beta-adrenoceptor blocking potency, but was highly correlated with drug lipophilicity. (+)-Propranolol was an effective uptake inhibitor, as was the local anaesthetic procaine. Kinetic analysis of uptake inhibition by propranolol, oxprenolol, metoprolol and procaine revealed a mixed inhibition for all four agents examined. It is suggested that this effect of beta-adrenoceptor blockers may be mediated, at least in part, by an action on membrane phospholipids associated with the noradrenaline carrier protein, and that noradrenaline uptake inhibition may underlie certain central side-effects observed with some drugs in this group.

Factors associated with a good response to lithium in aggressive mentally handicapped subjects

Twenty-five (25) mentally handicapped in-patient adults with persistent aggressive behaviour took part in a double-blind crossover trial lasting 5 months comparing the effects of lithium with placebo on aspects of aggressive behaviour. All patients were receiving neuroleptic and/or anticonvulsant drugs which were continued during the trial. Seventeen (17) of the patients showed greater improvement during the lithium phase compared to placebo. Multiple regression analysis was carried out to determine which of 17 background variables were related to outcome. The following factors were associated with a good response to lithium: less than one aggressive episode per week before starting treatment, overactivity, stereotypic behaviour, female sex and epilepsy. No patient became toxic during the investigation although lithium levels were maintained within the therapeutic range (0.5-0.8 mmol/l).

Migration of blood-borne lymphocytes into antigen-stimulated lymph nodes. A study of the kinetics of lymphocyte recruitment throughout an immune response

The kinetics of lymphocyte recruitment into rat popliteal lymph nodes stimulated with varying doses of allogeneic lymphocytes or purified protein derivative of tuberculin differed markedly. The number of blood-borne lymphocytes entering lymph nodes stimulated with allogeneic lymphocytes was greater and the duration of their entry more prolonged than in lymph nodes stimulated with the soluble antigen purified protein derivative of tuberculin. When individual antigenic doses were compared, lymphocyte recruitment into popliteal lymph nodes was shown to be dependent upon antigenic dose; higher doses of antigen resulting in increased levels of lymphocyte recruitment. In addition it was found that there is no linear relationship between lymph node weight changes and the extent of lymphocyte recruitment.

Survival and outcome of infants 501 to 750 gm: a six-year experience

We investigated the outcome of 60 infants with birth weight 501 to 750 gm, admitted to our neonatal intensive care unit over six years. Twenty-five infants were inborn and 35 outborn. Twenty-eight survived 28 days or longer (47%), and 24 were discharged (40%). The infants who died had a significantly increased incidence of intracranial hemorrhage, and their mothers had a significantly decreased use of tocolytic drugs and betamethasone. Of the 24 survivors, two died after discharge, leaving 22 long-term survivors. Of these, 18 (82%) were observed until 20 months to 7 years of age. Mean height and weight were near the fifth percentile until 3 years of age, then increased to the tenth to fiftieth percentiles between 4 and 6 years. Mean head circumferences always remained between the tenth and fiftieth percentiles. Mean IQ was 100.0 +/- 17.9 for the inborn and 87.2 +/- 15.1 for the outborn infants (excluding two whose IQ was less than 50). Two infants (11%) had neurologic sequelae, 12 (67%) were completely normal, and four (22%) were functional and of borderline or below average intelligence. No statistical differences were found between the inborn and outborn children. This study indicates that, with aggressive therapy, outcome of the infant with birth weight 501 to 750 gm is much improved.

Effect of epinephrine on PO2 in anterior chamber

A polarographic oxygen electrode was inserted through the cornea into the middle of the anterior chamber, and the aqueous humor PO2 was continuously monitored. Epinephrine hydrochloride applied topically to the cornea (1% Epifrin: 0.05 to 0.1 mL) or injected into the anterior chamber (Adrenalin Chloride: 1 mg/mL, 0.05 mL) caused a marked decrease in the anterior chamber PO2. This drop in anterior chamber PO2 was not simply due to mydriasis, since atropine sulfate administered in a similar fashion did not cause a notable drop in anterior chamber PO2, and epinephrine applied to eyes with the pupils previously dilated with atropine still caused the typical drop in anterior chamber PO2. The hypoxic effects of epinephrine were reversed by injection of an alpha-adrenergic blocker, phentolamine mesylate (5 mg/mL, 0.05 mL), into the anterior chamber.

Activities of some enzymes of glucose metabolism in bovine liver and kidney cortex at three stages of lactation

The activities (per g of tissue) of hexokinase, phosphofructokinase and pyruvate kinase were unchanged throughout lactation in liver and in kidney cortex. In both these tissues glucose 6-phosphatase activity decreased during late lactation. At the same time fructose diphosphatase activity increased in kidney cortex but not in liver. Activities of the pentose cycle dehydrogenases and of aspartate aminotransferase tended to increase in mid lactation. For most enzymes the activities at peak lactation were similar to those for dry, non-pregnant cows and there was no specific response of the gluconeogenic enzymes. Total hepatic contents of most enzymes tended to increase in mid lactation, but the changes were not clear cut and were the result of an increase in liver size.

Transurethral ureterolithotomy

The technique of transurethral ureterolithotomy for calculi impacted in the intramural ureter is described. Follow-up date on a group of 30 patients treated by this method are presented. Vesicoureteric reflux was found to occur in almost 50% of cases. The presence of reflux was not found to cause symptoms, infection or renal destruction. Therefore transurethral ureterolithotomy is recommended for the removal of intramural ureteric stones not suitable for basket extraction.

Comparison of the effects of transcortical and transcallosal removal of intraventricular tumours

Intelligence and memory functions were tested in 2 patients in whom the corpus callosum had been partially sectioned to remove intraventricular cysts or tumours and in 2 patients in whom similarly-located cysts or tumours had been removed transcortically. A patient with congenital absence of the corpus callosum was also tested. Callosal lesions per se did not appear to be responsible for memory deficits.

The significance of urine leak after pyeloplasty

The records of 126 pyeloplasties were reviewed to discover the relationship, if any, between the duration of urine leak after surgery and the success or failure of the procedure. Half of the cases drained urine for 7 days or less. In 26 patients the urine leak lasted from 15 to 28 days: in 23 of the 26 the outcome was successful. It is concluded that a urine leak of up to 28 days' duration is not of itself an indication for further interference. A breakdown of cases into type of operation and status of the operator (consultant or trainee) revealed no significant differences.

Ocular penetration of 5-fluorocytosine

Ocular penetration of 5-fluorocytosine (5FC) was studied in uninfected rabbits after subconjunctival and oral administration. With oral administration, 5FC achieved therapeutic levels in both the vitreous and aqueous humors. The use of a pharmacokinetic model permitted objective comparison of kinetic events within the eye chambers and the serum. The rates of entry and elimination in the vitreous were found to be slower than those in the aqueous, but the mean concentration over 24 hr was the same. The therapeutic levels achieved in the aqueous after subconjunctival administration were of shorter duration, and no detectable levels occurred in the vitreous. Oral administration is clearly therapeutically superior to subconjunctival administration in this model.

Effect of lactation on lipolysis in rat adipose tissue

The concentrations of nonesterified fatty acids and glycerol in rat parametrial adipose tissue increased at peak lactation. Adipose tissue from lactating rats showed higher rates of release of nonesterified fatty acids and glycerol when incubated in vitro than did tissue from nonlactating rats, but there was a substantial increase in the esterification of fatty acids during involution. These results support earlier evidence that fat reserves were mobilized during lactation.

Composition of liver lipids of the rat during pregnancy and lactation

Triglyceride concentrations in rat liver rose during late pregnancy, declined at peak lactation, and then rose again during involution. The percentage of oleate in the triglycerides rose at peak lactation, but that of linoleate fell. Although phospholipid concentrations were unchanged, the percentage of palmitate in this fraction rose, and those of stearate and arachidonate fell during pregnancy and lactation. These changes may be related to the changes in lipogenesis and fat mobilization that occur during pregnancy and lactation.

The composition of the liver lipids of the ewe during pregnancy and lactation

During late pregnancy and early lactation there were significant increases in the concentrations of triglycerides and cholesteryl esters in the liver lipids of the ewe. These changes were accompanied by higher concentrations of oleic acid and lower concentrations of stearic acid in both fractions, and may be related to an increased mobilisation of fatty acids from adipose tissue.

Phenotypic characterization of R-factor tetracycline resistance determinants

The tetracycline-resistance determinants of R-factors from different compatibility groups have been tested inEscherichia coliK12 and phenotypically classified into two major classes. Class I determinants confer high-level resistance to tetracycline (> 100 μg/ml) and moderate resistance to minocycline (5–25 μg/ml) while those of Class II gave moderate resistance to tetracycline (50–70 μg/ml) and low resistance to minocycline. Each class was subdivided because of variation in resistance profiles and in the abilities of tetracycline and minocycline to induce increased resistance. Strains carrying two compatible TetrR-factors of the same or different phenotypic groups did not show increased tetracycline resistance.