One- and two-dimensional echocardiography in bodybuilders using anabolic steroids

The object of this study was to investigate the possible concentric increase in the left ventricular (LV) wall thickness by intensive strength training and to differentiate between the specific effect of the strength training itself and the influence of anabolic drugs. In this study 21 top-level bodybuilders [users of anabolic steroids (A): n = 14; non-users (N): n = 7] underwent one-dimensional and two-dimensional echocardiography as well as a cycle ergometer test. In both groups blood pressure at rest and during ergometric exercise was within the normal range. In spite of the same amount of time being spent on training, A showed significantly better power results than N. Total heart volume (A = 11.3 +/- 0.9 ml.kg-1; N = 11.9 +/- 0.9 ml.kg-1) and LV muscle mass were almost identical in A and N and correlated significantly with body weight and lean body mass respectively. The body dimension-related diastolic LV diameter was significantly lower in A (0.567 +/- 0.062 mm.kg-1) than in N (0.639 +/- 0.040 mm.kg-1). An increase in the LV posterior wall (p less than 0.01) and septum thickness (ns) resulted in increased LV wall thickness:diameter (p less than 0.01) and LV muscle mass:volume (p less than 0.05) ratios in A (0.458 +/- 0.590; 1.38 +/- 0.25 g.ml-1) in comparison to N (0.356 +/- 0.077; 1.16 +/- 0.17 g.ml-1). The septal:posterior wall thickness ratio was similar for both groups.(ABSTRACT TRUNCATED AT 250 WORDS)     

Gastric emptying and serum insulin levels after intake of glucose-polymer solutions

To examine the gastric emptying characteristics of four drinks varying in carbohydrate composition and concentration, five men ingested 600 ml of one of the different drinks on four separate occasions. All drinks contained Na+ 71 mmol.l-1, Cl- 60 mmol.l-1, Mg+2 5 mmol.l-1 and citrate 7 mmol.l-1; the carbohydrate component was either 3% glucose, 3% glucose-polymer (GP), 5% GP or 10% GP. With 99mTc-diethylene-triaminepenta-acetic acid (DTPA) as a marker, a scintillation camera and computer were used to measure the rate of gastric emptying. The half-emptying times (T 1/2) were inversely related to the glucose content of the solutions. The T 1/2 for 3% PG was 22.4 +/- 4.4 min (mean +/- SE) and for 10% GP 50 +/- 3.3 min (p less than 0.005). There was no significant difference in T 1/2 between the 3% glucose and 3% GP solutions. The increments in blood glucose (highest blood levels from 7.4 +/- 0.3 mmol.l-1 to 8.9 +/- 0.8 mmol.l-1), serum insulin (from 28 +/- 6 mU.l-1 to 77 +/- 13 mU.l-1) and C-peptide (from 3.6 +/- 0.4 micrograms.l-1 to 5.8 +/- 0.9 micrograms.l-1) were related to the amount of carbohydrate ingested. In all cases the serum insulin levels were high enough to inhibit the liberation of free fatty acids from the adipose tissue. It is concluded that the amount of carbohydrate in glucosyl units in the solution is a major determinant of gastric emptying.(ABSTRACT TRUNCATED AT 250 WORDS)     

Simultaneous analysis of skin response to the different L.E.T. regions of a 55 MeV helium ion beam

Summary Rat tail epidermis was used to analyze the in vivo response of a biological system to heavy particle irradiation. The conical configuration of the rat tail gives rise to a variable energy degradation of the beam thus yielding information on the damage elicited by 2 different L.E.T. regions of the helium beam at different sites on the same sample. Cytochrome oxidase activity and epidermal thickness were used to analyze the metabolic and structural radioinduced response. Quantitative evaluation of radiation damage revealed marked variations within a few micrometers of tissue.     

Potency of microwave irradiation during fixation for electron microscopy

Liver, skeletal muscle, peripheral nerves, pancreas, thyroid and adrenal cortex were prepared for electron microscopy employing microwave energy either during prefixation with glutaraldehyde or instead of prefixation. Microwave irradiation in the presence of glutaraldehyde in Na/K-phosphate or Na-cacodylate containing CaCl2 and MgCl2 led to distinct appearance of membranes, mainly plasma membrane, and membranes of SER, Golgi complex and mitochondria in liver, pancreas and muscle. The area of high quality fixation, however, was limited to the periphery of samples. On the other hand, SER was dilated in cells of the adrenal cortex, and RER markedly vacuolated in thyroid follicular cells. Microwave irradiation in the presence of Na/K-phosphate and subsequent osmication resulted in preservation of the ultrastructure in similar quality as was obtained by osmication without previous immersion in glutaraldehyde. However, the preservation of SER and Golgi complex in liver and pancreas, and of mitochondria in muscle was greatly improved. Small myelin sheaths remained intact whereas large ones showed focal disintegration. We consider that enhancement of fixation by microwave energy may greatly improve preservation of membranes in some tissues. Successful fixation depends on the use of glutaraldehyde during microwave irradiation, the type of buffer, the addition of ions to increase stabilization, the exposure time to heat, and on postosmication.     

Protection of rainbow trout against vibriosis and furunculosis by the use of attenuated strains of Vibrio anguillarum

The fish pathogen Vibrio anguillarum causes a lethal infection in rainbow trout (Salmo gairdneri). Three different avirulent mutants, constructed by transposon insertion mutagenesis (VAN20 and VAN70) or as antibiotic-resistant mutants (VAN1000), were isolated by screening 200 individual isolated mutants for avirulence. When used as live vaccines, all three avirulent mutants were able to induce protective immunity against the homologous as well as a heterologous strain of V. anguillarum. When VAN1000 was used, protective immunity could be recorded 1 week after bath vaccination with 10(7) bacteria per ml of water for 30 min. A single-dose immunization was effective for at least 12 weeks. Western immunoblotting showed that strains of V. anguillarum have antigenic determinants in common with Aeromonas strains. Therefore, we tested and confirmed that VAN1000 also was able to induce protective immunity against challenge with Aeromonas salmonicida.     

Expression of denitrification enzymes in response to the dissolved oxygen level and respiratory substrate in continuous culture of Pseudomonas stutzeri

The onset and cessation of the synthesis of denitrification enzymes of Pseudomonas stutzeri were investigated by using continuous culture and defined dissolved oxygen levels covering the full range of transition from air saturation to complete anaerobiosis. Expression of nitrate reductase, nitrite reductase (cytochrome cd1), and N2O reductase was controlled by discrete oxygen levels and by the nature of the nitrogenous oxide available for respiration. N2O reductase was synthesized constitutively at a low level; for enhanced expression, oxygen concentrations were required to decrease below 5 mg of O2 per liter. The threshold values for synthesis of nitrate reductase and cytochrome cd1 in the presence of nitrate were ca. 5 and ca. 2.5 mg of O2 per liter, respectively. With nitrous oxide as the respiratory substrate, nitrite reductase was again the most sensitive to oxygen concentration; however, thresholds for all denitrification enzymes shifted to lower oxygen levels. Whereas the presence of nitrate resulted in maximum expression and nearly uniform induction of all reductases, nitrite and nitrous oxide stimulated preferably the respective enzyme catalyzing reduction. In the absence of a nitrogenous oxide, anaerobiosis did not induce enzyme synthesis to any significant degree. The accumulation of nitrite seen during both the aerobic-anaerobic and anaerobic-aerobic transition phases was caused by the differences in onset or cessation of synthesis of nitrate and nitrite reductases and an inhibitory effect of nitrate on nitrite reduction.     

Bacterial hydrophobicity, an overall parameter for the measurement of adhesion potential to soil particles

The adhesion of Salmonella typhimurium to the mineral particles quartz, albite, feldspar, and magnetite was shown to correlate with the hydrophobicity of the cell surface as measured by hydrophobic interaction chromatography. The same effects were also seen for seven other selected test strains, including Streptococcus faecalis, Streptococcus faecium, Escherichia coli, Citrobacter freundii, Shigella sonnei, and Shigella boydii. When the test strain of Salmonella typhimurium, was repeatedly cultivated in Luria broth, thus selecting for different degrees of fimbriation and roughness of the cell surface, varied cell hydrophobicity but constant negative and positive charge values were obtained. High hydrophobicity values always coincided with enhanced adhesion to the mineral particles. The negative charge of the bacterial surface as measured by electrostatic interaction chromatography appeared to play no role in the adhesion event. However, the positive charges on the cell surface contributed to the adhesion process. This was especially evident for cells exhibiting a high degree of hydrophobicity. Alteration of the pH between 4 and 9 did not significantly affect the adhesion process.     

Interaction of monoclonal antiparathyroid antibody with Ca2+ agonistic actions of Mn2+ in normal human parathyroid cells

Effects of the monoclonal antiparathyroid antibodies G11 and E11 on Mn2+ interaction with individual normal human parathyroid cells were studied. At 0.5mM Ca2+, 3mM Mn2+ induced a rapid transient increase in cytoplasmic Ca2+ [Ca2+i] followed by quenching of the fluorescence from the Ca2+ indicator fura-2 as Mn2+ entered into the cells. Whereas the antibody E11 had no effects, treatment with G11 abolished the Ca2+i transient and considerably delayed the entry of Mn2+. The results support the presence of a cation-sensitive receptor mechanism on parathyroid cells and indicate that the antibody G11 not only blocks the interaction between Ca2+ and this receptor mechanism but also that of Mn2+.     

31P nuclear magnetic resonance study of the effect of azide on xylose fermentation by Candida tropicalis

Maximal ethanol production by Candida tropicalis grown on xylose was obtained at an oxygen transfer rate of 5 to 7 mmol/liter per h. Addition of 0.2 mM azide increased the ethanol yield by a factor of 3 to 4, based on the cell mass produced, and decreased the formation of the by-product xylitol by 80%. In the presence of azide, ethanol was reassimilated before the carbon source was depleted. At all oxygenation levels studied, azide caused 25 to 60% of the carbon to be lost, most probably as carbon dioxide. Identical spectra were obtained with 31P nuclear magnetic resonance spectroscopy performed on extracts of C. tropicalis grown on xylose in the absence and presence of azide. Azide lowered the levels of sugar phosphates. Enzymatic analysis showed extremely low levels of fructose 1,6-diphosphate compared with the levels obtained in the absence of azide, while the level of malate, a citric acid cycle intermediate, was not influenced by azide. 31P nuclear magnetic resonance spectroscopy performed on xylose-grown whole cells of C. tropicalis showed that azide lowered the intracellular pH, inhibited the uptake of external Pi, and decreased the buildup of polyphosphate in relation to results with untreated cells. Similar results were obtained with the uncoupler of oxidative phosphorylation carbonyl cyanide m-chlorophenylhydrazone (CCCP), except that CCCP treatment led to extremely high levels of internal Pi. The dual effect of azide as a respiratory inhibitor and as an uncoupler is discussed with respect to the metabolism and product formation in xylose-assimilating C. tropicalis.     

Development of an enzymatic procedure to produce high-protein amaranth flour

Summary A basic procedure was developed to produce high-protein amaranth flour (HPAF) using a commercial preparation of heat-stable alpha-amylase. Slurries (20%, w/v) of gelatinized whole flour were liquefied at 70 and 90°C, pH 6.5, 0.1% (w/v) enzyme concentration and 30 min hydrolysis time. Protein content of raw flour was increased from 15 to 29.6 or 39.3% at liquefaction temperatures of 70 or 90°C, respectively. Some physicochemical and functional properties of HPAF were assessed. HPAF might be used as a dry milk extender.