Prevention of femoral vein occlusion by local injection of Thrombolysin in the rat

An experimental model was developed that will produce femoral vein occlusion greater than 90% of the time in rats weighing less than 500 grams. This standard venous clot, produced by combining intimal trauma with local venous stasis, can simulate clinical crush and replantation problems. Using this standard clot model, Thrombolysin was injected in the femoral artery after trauma to the vein but before venous stasis. Femoral vein patency was determined at the end of the 30 minute period of venous stasis. With the appropriate dosage, ipsilateral venous occlusion was prevented (P less than 0.00001) without preventing contralateral venous occlusion (P less than 0.02). Except for decreased fibrinogen levels, there was no significant change in the factors studied between the control and experimental groups. It is possible, therefore, to prevent thrombosis in a vein with intimal damage, even in the presence of a low-flow state by the local injection of Thrombolysin, without producing systemic anticoagulation.

Selective polyamine-binding proteins. Spermine binding by an androgen-sensitive phosphoprotein

Rat ventral prostate contains an acidic protein which can bind spermine selectively. The relative binding affinities of various aliphatic amines for the protein are, in decreasing order, spermine greater than thermine greater than greater than putrecine greater than 1,10-diaminodecane, cadaverine and 1,12-diaminododecane. The binding protein has an isoelectric point at pH 4.3 and a sedimentation coefficient of 3 S. Its molecular weight is approx. 30 000. Histones and nuclear chromatin preparations of the prostate can interact with the binding protein. The spermine-binding activity of the purified prostate protein can be inactivated by treatment with intestinal alkaline phosphatases. The phosphatase treated preparation can then be reactivated by beef heart protein kinase in the presence of cyclic AMP and ATP. The spermine-binding activity of the prostate cytosol protein fraction decreases after castration, but increases very rapidly after the castrated rats are injected with 5alpha-dihydrotestosterone. This finding raises the possibility that, in the postate, certain androgen actions may be dependent on the androgen-induced increase in the acidic protein binding of polyamines and their translocation to a functional cellular site such as nuclear chromatin. In the prostate cytosol, spermine also binds to 4-S tRNAs and to a unique RNA which has a sedimentation coefficient of 1.5 S.

Infarction of the gallbladder: a complication of hypertension. Case report

A case of gallbladder infarction, occurring in a 34-year old man with severe hypertension is described, with uneventful recovery following cholecystectomy. In the absence of other obvious etiologic factors, the gallbladder infarction is presumed to be directly related to hypertensive vascular disease. Infarction of the gallbladder is rare; a few cases associated with hypertension have been previously reported. Other types of vascular disease including embolization, thrombosis complicating atherosclerosis and celiac angiography, polyarteritis nodosa, occlusion following torsion and cystic vein thrombosis have been reported to cause gallbladder infarction.

Transannular dioxygenation of 9,10-dimethyl-1,2-benzanthracene by cytochrome P-450 oxygenase of rat liver

9,10-Dimethyl-1,2-benzanthracene is oxygenated by rat liver microsomal cytochrome P-450 oxygenase to its 9,10-epidioxide. This transannular 1,4-peroxide is converted further into the diol by the microsomal preparation and NADPH. These two products constitute the majority of the metabolites found under the conditions described.

Combined effects of rate membrane potential, and drugs on maximum rate of rise (Vmax) of action potential upstroke of guinea pig papillary muscle

We studied the effect of increasing the rate of stimulation on the maximum rate of rise of the action potential upstroke (Vmax) in guinea pig papillary muscles at various resting membrane potentials and after the addition of quinidine and lidocaine to the perfusate. Increasing rate caused a decrease in Vmax due to interaction of three factors: (1) a metabolic factor, presumably resetting of the Na-K pump, which caused a decrease in Vmax at all levels of resting potential between -90 and -60 mV, (2) a transient decrease in resting potential which influenced Vmax when the resting potential was less negative than approximately -80 mV, and (3) the recovery characteristics of Vmax which contributed to the decrease in this variable when rate was faster than 5/sec. As a result of these factors the steady state curve relating membrane potential to Vmax was itself rate-dependent. Lidocaine and quinidine exaggerated the rate-dependent decrease in Vmax; however, their effects differed. The effect of quinidine was consistent with its known depressant effect on the Na-K pump. The lidocaine effect was consistent with a slowing of recovery of Vmax. Our results help to explain the effects of an increase in rate on Vmax and conduction velocity in normal, partially depolarized, and drug-treated fibers

Interaction of cholera enterotoxin with cultured adrenal tumor cells

In the adrenal tumor cell system ganglioside Gm1 inhibited cholera enterotoxin (CT)-induced steroidogenesis if it was preincubated with the toxin or added to adrenal cells 10 min before CT. In the preincubation studies a molar ratio of Gm1 to toxin of 3:1 was necessary for half-maximal inhibition of steroidogenesis. On the other hand, horse serum anticholeragenoid neutralized the steroidogenic response to cell-bound CT by 50% if it was added to adrenal monolayer cultures 15 min after the toxin. Specific antiserum was able to neutralized 20% of the toxin-induced activity even if it was added to adrenal cultures 2 h after CT. Phase contrast microscopy demonstrated that partial neutralization of the biochemical effect of CT by horse serum anticholeragenoid was accompanied by partial prevention of toxin-induced rounding of adrenal cells. Further studies showed that pretreatment of cultured adrenal cells with a maximal dose of CT increased cyclic adenosine 3'-5'-monophosphate formation in response to a maximal stimulating dose of adrenocorticotropin. This result suggested potentiation of hormonal activation of adenylate cyclase in intact adrenal tumor cells in response to CT.

Biosynthesis and cytokinin activity of 8-hydroxy and 2,8-dihydroxy derivatives of zeatin and N-6(increment-2-isopentenyl)adenine

8-Hydroxy and 2,8-dihydroxy derivatives of the cytokinins, 6-(4-hydroxy-3-methyl-trans-2-butenylamino)purine and N-6-(increment -2-isopentenyl)adenine, have been biosynthesized by xanthine oxidase oxidation. 8-Hydroxy derivatives have been shown to be the major intermdeiates. These compounds were tested for cytokinin activity in the tobacco bioassay. The results suggest that substitution of the 8 position with a hydroxyl group causes less decrease of cytokinin activity than substitution of both the 2 and 8 positions with hydroxyl groups.

Neonatal thyroxine administration, behavioral maturation, and brain growth in mice of different brain weight

L-thyroxine in amounts of .5, 1, and 2 mug was injected daily from age 5 through 14 days in 3 lines of mice selected for high (H), medium (M), or low (L) brain weight. Controls (injected with vehicle only) of these lines differed in ages of eye-opening, first auditory startle, and perfection of a surface-righting response. Thyroxine at .5 mug/day accelerated the maturation of eye-opening, auditory startle, and aerial-righting response, but had no effect on a grasping response or open-field activity. Brain weights were depressed significantly in all thyroxine treated groups except in the 9k-mug dosage in H mice.

Culdoscopic ligation as an outpatient procedure

The increasing demand for abortion and sexual sterilization has caused the need to perform such operations on an outpatient basis. The University Department of Obstetrics and Gynaecology, Singapore, started a prospective study of culdoscopic ligation as an outpatient procedure in November, 1972. To date, over 600 operations have been performed. Analysis of the first 405 cases showed a low complication rate of 2.4 per cent. This study showed that culdoscopic ligation performed in the hospital outpatient is safe and feasible.

In vitro interaction of estrogen and prolactin on hormone-dependent rat mammory tumors (38511)

Hormone-dependent, regressing mammary tumors in rats were incubated in a chemically defined culture medium containing tritium labeled leucine at 37 degrees for 2 hr. The rate of tritium incorporation into the protein fraction by these tissues was measured with and without the addition of 17beta-estradiol and/or ovine prolactin into the medium. Tumor tissue responded to either estrogen or porlactin by a 6-7% increase in the rate of 3-H-leucine incorporation. When the incubation medium contained both the hormones, the increase in the rate of 3-H leucine incorporation was 19% which was significantly greater than the sum of the effect of each single hormone measured independelntly. These results demonstrate a synergistic effect between estrogen and prolactin on rat mammary tumors.

Cyclic metabolic pathway of a butylated hydroxytoluene by rat liver microsomal fractions

A cyclic metabolic pathway was obtained when 3,5-di-t-butyl-4-hydroxytoluene (BHT) was incubated with a rat liver microsomal preparation. The pathway is as follows: BHT --> 4-hydroperoxy-4-methyl-2,6-di-t-butylcyclohexa-2,5-dienone (BHT-OOH) --> 4-hydroxy-4-methyl-2,6-di-t-butylcyclohexa-2,5-dienone (BHT-3(0)OH) --> BHT. This metabolic pathway suggests that antioxidants such as BHT owe their high efficacy, at least in part, to their metabolic regeneration.

Observations of gonadotrophic and ovarian hormone activity during recovery from anorexia nervosa

Serum gonadotrophins and gonadal steroids were measured in six unmarried female patients with anorexia nervosa before and during treatment by feeding and psychotherapy, which led to restoration of weight to matched population mean levels. In three patients whose premorbid weight was normal, hormonal levels during treatment were initially low, but as weight was regained gonadotrophic levels increased and one patient showed cyclical activity. In three other patients who were premorbidly obese gonodotrophic levels did not appear to increase over the period of investigation. With the exception of one patient whose menstrual cycles were resumed during the period of investigation, gonadal steroid levels in general appeared to remain low although, subsequently, regular monthly menstrual bleeding occurred in some of these patients.

Stereotactic limbic leucotomy: a preliminary report on forty patients

The neurophysiological aspects and operative technique of stereotactic limbic leucotomy have been described in a previous paper (Kelly, Richardson and Mitchell-Heggs, 1973). The present investigation is a prospective study designed to assess the results of such surgery in a group of 40 severely ill psychiatric patients, who had failed to respond satisfactorily to every other type of treatment. The results have been assessed clinically, psychologically and physiologically, in a very detailed way, at six weeks; a similar follow-up at one year is in progress. A comparison is made between the results of the present series and those of a previous: study (Kelly et al., 1972), in which more extensive leucotomy operations were carried out, and similar means of assessment were employed.

The effects of mercaptoethanol and of peritoneal macrophages on the antibody-forming capacity of nonadherent mouse spleen cells in vitro

Nonadherent mouse spleen cells exhibited poor viability and little or no capacity to form antibodies to sheep red cells in the Mishell-Dutton culture system. Viability and antibody-forming capacity could be restored by addition to these cultures of low concentrations of mercaptoethanol (10(-4)-10(-5)M), or by addition of appropriate numbers of mouse peritoneal macrophages. Macrophage concentrations lower than optimal resulted in lower lymphoid cell viability and correspondingly fewer plaque-forming cells, whereas excess macrophages resulted in marked inhibition of antibody formation despite good viability of the lymphocytes. Restoration of the nonadherent cells with mercaptoethanol was thus much simpler and more reproducible than it was with macrophages; furthermore, the number of plaque-forming cells developed in cultures restored with mercaptoethanol was approximately fourfold higher than it was in cultures restored with optimal numbers of macrophages. In the presence of mercaptoethanol, the plaque-forming capacity of the nonadherent spleen cells was not increased when small numbers of macrophages were added to the system, nor was it decreased when the few macrophages present in the nonadherent cells were further reduced or eliminated. Excess macrophages inhibited antibody formation in the cultures containing mercaptoethanol as they did in control cultures. Optimal restoration of plaque-forming capacity to the nonadherent spleen cells with mercaptoethanol required the reducing agent to be present throughout the 4 or 5 day culture period. Addition of mercaptoethanol 1 or more days after initiation of culture, or transfer of the cells to a medium free of mercaptoethanol before completion of the culture resulted in a reduction in the numbers of plaque-forming cells. The results suggest that mouse lymphoid cells do not require macrophages in order to form antibodies to sheep red cells in vitro, provided mercaptoethanol is present in the culture medium. The mechanism of action of mercaptoethanol under these conditions is not completely clear, but one of its effects is to promote the viability of lymphoid cells in the cultures.

Ring hydroxylation of di-t-butylhydroxytoluene by rat liver microsomal preparations

3,5-Di-t-butylhydroxytoluene (compound I) was converted into 4-hydroperoxy-4-methyl-2,6-di-t-butylcyclohexa-2,5-dienone (compound II), 4-hydroxy-4-methyl-2,6-di-t-butylcyclohexa-2,5-dienone (compound III) and 2,6-di-t-butyl-4-hydroxymethylphenol (compound IV) by rat liver microsomal preparations in the presence of NADPH and air. The oxidation of compound (I) by m-chloroperbenzoic acid also produced the same compounds. These results suggest that hydroperoxide can be an intermediate in aromatic hydroxylation and that biological oxygenations resemble per-acid reactions.

Restoration of antibody-forming capacity in cultures of nonadherent spleen cells by mercaptoethanol

Populations of mouse spleen cells, without those cells that adhere to glass or plastic, exhibit little or no capacity for formation of antibody to sheep erythrocytes in the Mishell-Dutton culture system. When 5 x 10(-5)M mercaptoethanol is added to the culture medium, the antibody-forming capacity of these nonadherent spleen cells is restored to that of unfractionated spleen cells.

Purification and characteristics of pyocin B39 II. Physical and chemical properties

A purified preparation of pyocin B39 was shown to be homogeneous by disc electrophoresis and ultracentrifugation. Pyocin B39 is an antibacterial agent, protein in nature, and is capable of inhibiting the growth of susceptible cells. It caused a susceptible strain of Pseudomonas aeruginosa to release ultraviolet-absorbing material. Pyocin B39 appears to be a protein with a high molecular weight; its sedimentation coefficient is 32.8S. It was destroyed by 7 m urea but was resistant to attack by proteolytic enzymes, such as pepsin and trypsin. From its sedimentation coefficient, a molecular weight of about 2 x 10(6) was calculated. An electron photomicrograph of pyocin B39 revealed it as a rodlike particle, 7.50 pm long and 1.08 pm wide, with striations running at nearly right angles to the axes of the particle.