Right ventricular function in orthotopic total atrioventricular heart transplantation

BACKGROUND: Total orthotopic heart transplantation was recently introduced into clinical practice as an alternative technique of orthotopic heart transplantation, adding bicaval and left and right pulmonary vein anastomoses to pulmonary artery and ascending aorta connection (total technique). The conventional technique (ventricular transplantation with atrioplasty) is compared with the total technique with particular emphasis on right ventricular performance. METHODS: Forty-eight mongrel dogs (23 to 31 kg) were used for 12 total and 12 standard orthotopic heart transplantations. Right ventricular (RV) function and atrial systole were analyzed with the use of micromanometry, sonomicrometry, and ultrasonic flow probes (preload-independent RV recruitable stroke work, RVPRSW). Fourier analysis was used to calculate RV power and pulmonary vascular impedance. RESULTS: There was no significant difference in cardiac ischemic and bypass times between the two groups. After transplantation, sinus rhythm was preserved after all total transplantations and after only one standard transplantation; no significant hemodynamic differences were observed. RVPRSW in the total group was conserved after transplantation; however, RVPRSW decreased by 39% (+/-8, p < .05) in the standard group. There was also a significant decrease in the rate of RV filling in the standard group after transplantation, suggesting decreased right atrial function. Pulmonary vascular impedance and RV power output were not significantly different after transplantation between the two groups. CONCLUSIONS: Total atrioventricular transplantation is a feasible alternative and conserves normal sinus rhythm. Ischemic and bypass times were not significantly different when the superior vena cava anastomosis is performed last after the release of the aortic cross-clamp. The insignificant decrease in the rate of RV filling with the use of the total technique suggests conserved RV diastolic function after transplantation with less decreased RV function in the total group.     

Monoclonal antibodies to mammalian heat shock proteins impair mouse embryo development in vitro

Two-cell mouse embryos (B6D2F1) were cultured in the presence or absence of 100 microg/ml monoclonal antibodies specific for the mammalian 60 kDa (HSP60), 70 kDa (HSP70) and 90 kDa (HSP90) heat shock proteins. Embryo development was evaluated after 3, 5 and 7 days in culture by determining the number of blastocysts, hatched blastocysts and outgrown trophoblasts at the successive time points. At day 3, only 29% (22/75) of the embryos cultured with anti-HSP60 antibody developed to the blastocyst stage (P < 0.0001) as compared to 67% (31/46) of the embryos cultured with anti-HSP70, 72% (43/60) cultured with anti-HSP90, and 79% (49/62) in medium plus mouse IgG1. By day 5, hatched embryos were present in 28% (13/ 46) of the cultures containing anti-HSP70 (P < 0.0001), as opposed to 57% (34/60) containing anti-HSP90 and 73% (45/62) containing IgG1. At day 7, outgrown trophoblasts were observed in 9% (4/46) of cultures containing anti-HSP70 (P < 0.0001), 45% (27/60) containing anti-HSP90 (P < 0.01) and 66% (41/62) cultured in medium plus IgG1. Antibodies to different heat shock proteins exerted a detrimental effect on mouse embryo development at unique development stages. Immune sensitization to heat shock proteins may be a cause of reproductive failure.     

Mechanisms of anticarcinogenic properties of curcumin: the effect of curcumin on glutathione linked detoxification enzymes in rat liver

Clinicians lack a practical method for measuring CBF rapidly, repeatedly, and noninvasively at the bedside. A new noninvasive technique for estimation of cerebral hemodynamics by use of near-infrared spectroscopy (NIRS) and an intravenously infused tracer dye is proposed. Kinetics of the infrared tracer indocyanine green were monitored on the intact skull in pigs. According to an algorithm derived from fluorescein flowmetry, a relative blood flow index (BFI) was calculated. Data obtained were compared with cerebral and galeal blood flow values assessed by radioactive microspheres under baseline conditions and during hemorrhagic shock and resuscitation. Blood flow index correlated significantly (rs = 0.814, P < 0.001) with cortical blood flow but not with galeal blood flow (rs = 0.258). However, limits of agreement between BFI and CBF are rather wide (+/- 38.2 +/- 6.4 mL 100 g-1 min-1) and require further studies. Data presented demonstrate that detection of tracer kinetics in the cerebrovasculature by NIRS may serve as valuable tool for the noninvasive estimation of regional CBF. Indocyanine green dilution curves monitored noninvasively on the intact skull by NIRS reflect dye passage through the cerebral, not extracerebral, circulation.     

Molecular cloning and characterization of fengycin synthetase gene fenB from Bacillus subtilis

A fengycin synthetase gene, fenB, has been cloned and sequenced. The protein (FenB) encoded by this gene has a predicted molecular mass of 143.6 kDa. This protein was overexpressed in Escherichia coli and was purified to near homogeneity by affinity chromatography. Experimental results indicated that the recombinant FenB has a substrate specificity toward isoleucine with an optimum temperature of 25 degrees C, an optimum pH of 4.5, a Km value of 922 microM, and a turnover number of 236 s(-1). FenB also consists of a thioesterase domain, suggesting that this protein may be involved in the activation of the last amino acid of fengycin.     

Effects of large doses of estrogen on prolactin and growth hormone release

The effects of large doses of estrogen on prolactin (PRL) release were assessed. Circulating PRL levels in response to intravenous infusion of 17 beta-estradiol (E2), at a rate of 50 mug per hour for 4 hours, were studied in 10 subjects, and a chronic administration of ethinyl estradiol (EE) at a dose of 400 mug per day, for 1 week, was evaluated in five hypogonadal subjects. There was a significant depression of serum level of PRL during the E2 infusion and a significant increase in PRL release after discontinuation of the infusion. The chronic treatment of large doses of EE induced a more rapid (within 36 hours) and a significantly greater elevation of PRL levels at the end of 1 week treatment than those found during smaller doses of EE administration, as reported previously. These data suggest that acute treatment of estrogen may have a biphasic action on the pituitary PRL section and that the augmentatory effect of estrogen on PRL secretion is dose-dependent in human beings.     

Independent secretion of different digestive enzymes by the pancreas

Pancreatic secretion was collected from the cannulated duct of anesthetized rabbits during the perfusion of the upper duodenum with a balanced salt solution with or without 5 mM glucose. The secretion of amylase, chymotrypsinogen, trypsinogen, and total protein was measured. While glucose did not increase overall digestive enzyme secretion, it did change the proportions of the enzymes in secretion. In addition, the following was observed: 1) non-0,0 intercepts when the output of one enzyme was plotted against that of another (an enzyme-pair plot), 2) changes in the variance of the slope and intercept of enzyme-pair plots, and 3) an increase in the variance around the slope of an enzyme-pair plot, concurrent with a decrease in the variance around the slope of a plot for another enzyme pair that contained a common member. These observations suggest that different digestive enzymes can be secreted independently of each other.     

Effect of fluoride on root resorption of autogenous dental replants. Clinical study

One hundred and fifty teeth were replanted using three procedures and it was found that greater success occurred in teeth when the periodontal membrane had been removed prior to treatment with two per cent sodium fluoride solution before replantation. Retention of the periodontal membrane on the root surface of the alveolar bone was not significant in the success of replants and reduced the success of those replants which were treated with fluoride. Endodontic procedures were found to be time consuming without contributing to the success of the end result.     

The effect of L-dopa and chlorpromazine on prolactin and growth hormone secretion in normal women

The time course of simultaneous changes in prolactin (PRL) and growth hormone secretion in response to a single dose of L-dopa and chlorpromazine was determined in normal women. L-Dopa induced greater, but shorter (30 minutes), growth hormone release than concomitant suppression of PRL secretion. The PRL peak following chlorpromazine occurred at the same time as the nadir of PRL after L-dopa (3.5 hours). The quantity of PRL release inhibited by L-dopa equaled the amount of PRL secretion during the period of rebound, suggesting L-dopa inhibits PRL release, but not synthesis, by the pituitary.     

Isolation and characterization of three unusual membrane glycopeptides present in rat intestinal endoplasmic reticula

Three glycopeptides have been isolated from the mucosal homogenates of the rat small intestine without using proteolysis. These glycopeptides appear to be localized exclusively in the membranes of the endoplasmic reticula. Although they have similar molecular weights of about 2550 and have similar amino acid compositions, they differ in the carbohydrate constituents. The major glycopeptide has 2 mol glucose per polypeptide chain while the two other glycopeptides contain 1 mol fucose, mannose and galactose with either 1 or 2 mol glucose. No hexosamine or sialic acid was detected in any of the glycopeptides. An unusual physical property was found associated with these glycopeptides. Below pH 6.5 they formed a precipitate which prevented them from diffusing through a dialysis membrane and allowed them to be rapidly purified following solubilization from the membrane. These glycopeptides appear to represent a new group of heretofore uncharacterized membrane constitutents which may play a role in some function specific for the endoplasmic reticula.