Microtransferrinuria and microalbuminuria. I. In the diabetic human

We studied albumin, transferrin and total protein excretion in the urine of 110 diabetics visiting a family practice department. Of these patients 18.2% had an elevated total urinary protein above the reference range (greater than 200 mg/g creatinine). Of the remaining patients (normoproteinuria), 25.5% have elevated transferrin (greater than 0.9 mg/g creatinine) while 18.8% have elevated albumin (greater than 32 mg/g creatinine). The correlation coefficient between transferrin and albumin in urine when total urinary protein is normal was 0.77. Moderate exercise increased urinary transferrin in normal subjects 950%, while for albumin the increase was 440%. These data demonstrate the usefulness of microtransferrinuria, a potentially more sensitive indicator than microalbuminuria for diabetic nephropathy.     

Intestinal goblet cell mucus release. II. In vivo stimulation by antigen in the immunized rat.

We previously reported that the infusion of certain soluble immune complexes stimulated mucus release from the rat small intestine in vivo. The present studies sought to evaluate the response of the intestine of normal and immunized rats to the infusion of antigen alone. One hour after the intraduodenal infusion of antigen, small intestinal washings were obtained and analyzed for the presence of 35S-labeled, high m.w. glycoprotein of goblet cell origin. The amount of goblet cell glycoprotein released was estimated from the radioactivity present in the void volume of a Sepharose 4B gel filtration column. The release of goblet cell mucus was enhanced by antigen stimulation in orally immunized animals. The discharge of goblet cell mucus was not increased after antigen infusion in animals immunized by the i.p. route despite the induction of high levels of serum antibody. The inability to demonstrate release of mucus after antigen challenge in systemically immunized rats suggests that the amount or the type(s) of antibody required at the mucosal surface is produced only after oral immunization.     

Bromide kinetics and distribution in the rat. II

The distribution of 82Br-bromide in 15 different organs and tissues of rats has been determined by high-resolution gamma-ray spectrometry and by the scintillation counting technique at different times after the application of Na 82Br, either by subcutaneous injection or by continuous administration in the drinking water. The amount of 82Br-bromide in the various tissues reached its largest uptake within a few hours, and the concentration ratio of 82Br in the tissues to blood remained practically constant between 8 and 396 h after the application. The whole stomach of rats was the only organ of those investigated that had a larger uptake of 82Br than blood. Contrary to some previous findings, the concentration of radiobromide in the thyroid was found not to exceed that in the blood. A remarkably high concentration of 82Br was found in the skin, which represented, because of its large mass, the most abundant depot of bromide in the body of rats. The demonstrated excretion of bromide was mainly renal, at a rate of approximately 5% of the administered dose per 24 h.     

Increased microalbuminuria in diabetic rats is independent of angiotensin II or glomerular proteoglycan synthesis.

Increased microalbuminuria is seen early in rats with both streptozotocin-induced and genetic (Bio-Breeding) diabetes. This study examines the roles of angiotensin II-dependent mechanism(s) and sulfation of glomerular proteoglycans in this phenomenon, as both processes have been implicated by several lines of circumstantial evidence. Anionic sites in the glomerular basement membrane, attributed to the presence of heparan sulfate, were quantitated by polyethyleneimine staining at 15, 21, and 70 days of diabetes in rats treated with streptozotocin, with or without insulin, and at 70 days in the Bio-Breeding rats. All diabetic rats developed increased microalbuminuria: control, 0.08 +/- 0.03 microgram/mL glomerular filtration rate, mean +/- SD; streptozotocin without insulin at 15 days, 0.92 +/- 0.06 microgram/mL (p < 0.05); streptozotocin with insulin at 21 days, 0.61 +/- 0.37 microgram/mL (p < 0.05 vs. control). At 70 days, both the Bio-Breeding and the streptozotocin rats sustained their microalbuminuria to the same degree (p < 0.05 vs. control). Enalapril (250 mg/L) in the drinking water of diabetic animals did not reduce the microalbuminuria. Although the polyethyleneimine-stained heparan sulfate sites decreased significantly in the streptozotocin rats, they remained unchanged in the Bio-Breeding rats. To determine the cause of reduced heparan sulfate staining, the in vitro synthesis and degree of sulfation of proteoglycans by glomeruli isolated from control and streptozotocin diabetic rat kidneys were compared. The amount of heparan sulfate synthesis and degree of sulfation were unchanged in diabetic glomeruli, although lower incorporation into the extracellular matrix and greater secretion into the medium were noted.(ABSTRACT TRUNCATED AT 250 WORDS)     

In situ effector mechanisms in rat kidney allograft rejection. II. Heterogeneity of the effector cells in the inflammatory infiltrate vs that in the spleen of the recipient rat.

We have isolated the infiltrating inflammatory cells from rejecting rat kidney allografts via collagenase-DNase dispersion and 1g velocity sedimentation. A representative cell sample, devoid of blood contamination and subclass-specific cell losses, is thus obtained in a functionally viable state. The infiltrating inflammatory cells display an immunologically specific in vitro cytotoxicity to donor-strain lymphoblasts. The peak cytotoxicity takes place in the graft before it takes place in the lymphatic system of the recipient rat. The allograft-infiltrating cytotoxic cells display a far wider distribution profile in 1g velocity than do the recipient spleen killer cells. The donor-strain lymphoblasts are highly sensitive to the lytic effect of both allograft-infiltrating and spleen killer cells, but the transplant parenchymal cells, consisting mainly of tubular and glomerular cells, are relatively insensitive. The findings suggest heterogeneity of the effector cells in the allograft infiltrate vs that in the spleen, and indicate that different structures of the target organ are differently sensitive to cellular cytotoxicity.     

Morphine diesters. II. Blood metabolism and analgesic activity in the rat

The kinetics of hydrolysis of dipropanoylmorphine (DPM) and dibutanoylmorphine (DBM) in human blood fractions and for diacetylmorphine (DAM) and DBM in rat blood fractions were investigated. In each case the hydrolysis of morphine diesters terminated with the production of the corresponding 6-monoester derivative. Generally, decreases in Km and Vmax were observed for the plasma, red blood cell (RBC) cytosol, and RBC membrane esterases responsible for morphine diester hydrolysis as the alkyl chain length of the ester moiety increased. This resulted in an overall decrease in the rate of hydrolysis of morphine diesters by human or rat blood with longer chain homologs of DAM. The analgesic potency and duration of morphine, DAM, and DBM were assessed at various i.v. dosages in the rat by means of the tail-flick latency test. A comparison of equianalgesic doses of morphine, DAM, and DBM indicated that DAM and DBM were 11.5 and 6 times as potent and 0.8 and 1.2 times as long acting, respectively, as morphine.     

Lymphopoiesis in the rat. II. The effect of thymectomy

Lymphopoiesis with respect to recirculating and non-recirculating small lymphocytes was measured simultaneously in rats thymectomized as adults. Removal of the thymus at four to five weeks of age had a profound inhibitory effect upon the production of recirculating cells, whereas the formation of non-recirculating lymphocytes was only slightly depressed. Thymectomy had approximately the same impact of lymphopoiesis as thymectomy and exposure of the animal to a large dose of whole body X- and γ-irradiation. The latter finding, and the failure of a thoracic duct cell transfusion to augment lymphocyte production, accord with the view that the thymus is the principle intermediate source of recirculating small lymphocytes in the normal, unstimulated animal.     

II. In vitro studies of antibacterial activity

One hundred and forty isolates of beta-hemolytic streptococcus cultured from patients with clinical pharyngitis were studied by disc diffusion for antibiotic sensitivity to lincomycin, erythromycin, cephalexin and penicillin and by agar dilution to cephalexin and penicillin. All isolates were sensitive to ≤ 0.1 μg./ml. penicillin and ≤ 1.56 μg./ml. cephalexin. The disc-diffusion test was reliable in predicting the sensitivities in vitro. One strain of group A betahemolytic streptococcus was resistant to erythromycin by disc diffusion. When compared to Lancefield grouping 18% of strains were incorrectly identified as group A by the bacitracin-disc test. Cephalexin was uniformly effective in vitro in inhibiting beta-hemolytic streptococci and the 30 μg. cephalexin disc was reliable in predicting these sensitivities.     

The effect of ethanol upon early development in mice and rats. II. In vitro effect upon early postimplantation rat embryos

The direct effect of ethanol upon in vitro cultured 9.5 day rat embryos was investigated (2, 4, 8 and 10% ethanol added to the culture medium). The main effects recorded were as follows: 1. Significant increase of the number of "dying" embryos (beating heart without yolk sac circulation); 2. No significant increase of mortality; 3. Significant increase of the number of living embryos with deficient blood circulation; 4. Significant retardation of coiling in living embryos with a significant dose-effect relation, when the effects of 20/00 and 80/00 ethanol were compared; 5. Lowering of the mean somite number in living embryos; 6. Various macro- and macroscopical pathological changes (mainly necrotic areas in the central nervous system).