Oxygen- and Nitrogen-Dependent Sulfur Metabolism in the Thiotrophic Clam Solemya reidi.

We investigated aerobic and anaerobic thiotrophic metabolism by the gutless clam Solemya reidi and its intracellular symbiotic bacteria. Mean environmental sulfide concentrations in porewater next to animals varied from a high of 888 μM to a low of 17 μM in different sediment samples, while mean thiosulfate concentrations were very low (1-13 μM). The blood of freshly collected clams contained up to 300 μM thiosulfate but little sulfide (≤12 μM).

Thyroid control of contractile function and calcium handling in neonatal rat heart.

Newborn rats were rendered hyperthyroid (daily subcutaneous injections of L-triiodothyronine, 10 micrograms 100 g-1 body weight) or hypothyroid (0.05% 6-n-propyl-2-thiouracil in drinking water to nursing mothers) during the first 3 weeks of postnatal life. Compared with the euthyroid group, hyperthyroidism resulted in: (1) cardiac enlargement with right ventricular preponderance, (2) increased cardiac contractile function, (3) increased Ca2+ uptake by the sarcoplasmic reticulum (SR), (4) decreased sensitivity to the negative inotropic effect of verapamil and (5) greater inhibition of contractile function by ryanodine.

Mortality among laboratory workers employed at the U.S. Department of Agriculture.

We evaluated the mortality of 835 white male and 36 female laboratory workers employed by the U.S. Department of Agriculture who died between January 1, 1970, and December 31, 1979.

Identification and bioassay of sex pheromone components of carob moth,Ectomyelois ceratoniae (Zeller).

Three sex pheromone components of the carob moth were isolated and identified from the extract of female pheromone glands, using a variety of techniques including coupled gas chromatographic-electroantennographic recordings, coupled gas chromatographic-mass spectrometric analysis, microozonolysis, electroantennographic assays of monounsaturated standards, wind-tunnel bioassays, and field trials. The major component was identified as (Z,E)-9,11,13-tetradecatrienal, a novel lepidopterous pheromone component structure. Two minor components, either one of which improves the upwind flight response of males when blended with the major component, were identified as (Z,E)-9,11-tetradecadienal, and (Z)-9-tetra-decenal.

Thyroid control over membrane processes in rat heart.

We have studied the effects of hypo- and hyperthyroidism on sarcolemmal (SL) and sarcoplasmic reticular (SR) ion transport processes and mitochondrial energy production in rat heart. The following conclusions were derived. 1) Compared with euthyroid state, hyperthyroidism led to increased SR Ca(2+)-accumulation.

Immunoreactive fraction 1 leaf protein and dry matter content during wilting and ensiling of ryegrass and alfalfa.

In four experiments with ryegrass and alfalfa, cut herbage was wilted in the field and silage made in 1- or 200-L silos. Direct-cut (mean DM, 20.3%), low wilt (mean DM, 26.

A rapid procedure for the purification of cardiac 1,4-dihydropyridine receptors from porcine heart.

Highly purified porcine cardiac sarcolemma was used as a source for purification of mammalian cardiac 1,4-dihydropyridine receptors associated with the voltage-dependent Ca2+ channel. The cardiac digitonin-solubilized receptor prelabeled with (+)-[3H]PN 200-110 was enriched at least 236-fold using an improved, rapid three-step purification protocol which could be completed within 12 h. The purity of the preparation was at least 22%, the yield of the receptors 24%.

Role of sulfhydryl groups in phospholipid methylation reactions of cardiac sarcolemma.

The effect of reagents that modify sulfur-containing amino acid residues in the phosphatidylethanolamine N-methyltransferase was studied in the isolated rat cardiac sarcolemma by employing S-adenosyl-L-[methyl-3H]methionine as a methyl donor. Dithiothreitol protected the sulfhydryl groups in the membrane and caused a concentration- and time-dependent increase of phospholipid N-methylation at three different catalytic sites. This stimulation was highest (9-fold) in the presence of 1 mM MgCl2 and 0.

[Obstructive uropathies in early childhood--surgical intervention as renal protection].

Anomalies in the urinary tract can be noticed early by prenatal sonography. In the case of obstruction, a decompressive procedure can follow immediately after birth. Long-term results of renal function in cases of pyeloureteral obstructions after 6-10 years make it clear that results are better the earlier pyelon resection is performed.

Alteration of lipid methylation by oleic acid in rat heart sarcolemma.

Incubation of rat heart sarcolemma with the methyl donor S-adenosyl-L-[methyl-3H] methionine resulted in N-methylation of phosphatidylethanolamine and methylation of a heterogenous fraction of nonpolar lipids in the membrane. Oleic acid reduced the synthesis of N-methylated phospholipids and stimulated the methyl group incorporation into nonpolar lipids in a concentration-dependent manner. Both methylation reactions were not affected when oleic acid was substituted by methyl ester of oleic acid or by the detergents sodium deoxycholate or Triton X-100.

Production of thiosulphate during sulphide oxidation by mitochondria of the symbiont-containing bivalve Solemya reidi.

Isolated mitochondria of the bivalve Solemya reidi Bernard oxidize sulphide and couple this oxidation to ADP phosphorylation. The products of mitochondrial sulphide oxidation were analyzed by HPLC using monobromobimane derivatization. Concurrent measurements of respiration were made using sulphide-insensitive oxygen electrodes.

Effect of pulsed progressive fluoroscopy on reduction of radiation dose in the cardiac catheterization laboratory.

The increased application of therapeutic interventional cardiology procedures is associated with increased radiation exposure to physicians, patients and technical personnel. New advances in imaging techniques have the potential for reducing radiation exposure. A progressive scanning video system with a standard vascular phantom has been shown to decrease entrance radiation exposure.

Interactions between cyclic AMP-dependent protein phosphorylation and lipid transmethylation reactions in isolated porcine cardiac sarcolemma.

Premethylation of purified porcine cardiac sarcolemma (SL) in the presence of 0.15, 10 and 150 microM S-adenosyl-L-methionine (AdoMet) did not change the phosphorylation of SL proteins catalyzed either by intrinsic cyclic AMP-dependent protein kinase (cAK) or by added catalytic (C) subunit of this enzyme. On the other hand, membrane exhibited increased lipid methyltransferase activity after preincubation with MgATP and C subunit.

Measurement of body potassium with a whole-body counter: relationship between lean body mass and resting energy expenditure.

We conducted studies to determine whether the Mayo whole-body counter could be used to measure body potassium, and thus lean body mass (LBM), and whether moderate obesity alters resting energy expenditure when corrected for LBM. Twenty-four nonobese and 18 moderately obese adults underwent body potassium (40K) counting, as well as tritiated water space measurement and indirect calorimetry. LBM values predicted from 40K counting and tritiated water space measurements were highly correlated (P = 0.

Radiation exposure of fertile women in medical research studies.

Fertile women may be exposed to ionizing radiation as human subjects in medical research studies. If the woman is pregnant, such exposures may result in risk to an embryo/fetus. Fertile women may be screened for pregnancy before exposure to ionizing radiation by interview, general examination, or pregnancy test.

[Hamartoma of the liver in childhood].

Liver hamartoma is one of the very rare findings in childhood. It is a dysontogenetic malformation that grows clinically manifest with tumour-like appearance in the first or second year of age. Cystic and solid formations are described in this report.

Deep-sea hydrocarbon seep communities: evidence for energy and nutritional carbon sources.

Mussels, clams, and tube worms collected in the vicinity of hydrocarbon seeps on the Louisiana slope contain mostly "dead" carbon, indicating that dietary carbon is largely derived from seeping oil and gas. Enzyme assays, elemental sulfur analysis, and carbon dioxide fixation studies demonstrate that vestimentiferan tube worms and three clam species contain intracellular, autotrophic sulfur bacterial symbionts. Carbon isotopic ratios of 246 individual animal tissues were used to differentiate heterotrophic (8(13)C = -14 to -20 per mil), sulfur-based (8(13)C = -30 to -42 per mil), and methane-based (8(13)C = <-40 per mil) energy sources.

Dietary fat inhibits the intestinal metabolism of the carcinogen benzo[a]pyrene in fish.

Following the intestinal absorption of dietary benzo[a]pyrene (BP) by the killifish, this compound becomes incorporated along with dietary triglycerides into membrane-bound fat vacuoles within the intestinal epithelial cell (1985. J. Lipid Res.