Effect of the fatty acid composition of ingested fats on rat liver intermediary metabolism

A "chronic" study of an implantable bladder pacemaker revealed that, although the electrode array did not significantly impair vesical function during the 10 weeks of research, electric stimulation did spread to the voluntary perineal musculature. There was also a drop in bladder response to the same stimulation parameters, probably due to progressive development of fibrous reaction and encasement of electrodes.     

13C NMR study of the effects of leptin treatment on kinetics of hepatic intermediary metabolism

The recent discovery of leptin receptors in peripheral tissue raises questions about which of leptin's biological actions arise from direct effects of the hormone on extraneural tissues and what intracellular mechanisms are responsible for leptin's effects on carbohydrate and lipid metabolism. The present study is focused on the action of leptin on hepatic metabolism. Nondestructive 13C NMR methodology was used to follow the kinetics of intermediary metabolism by monitoring flux of 13C-labeled substrate through several multistep pathways. In perfused liver from either ob/ob or lean mice, we found that acute treatment with leptin in vitro modulates pathways controlling carbohydrate flux into 13C-labeled glycogen, thereby rapidly enhancing synthesis by an insulin-independent mechanism. Acute treatment of ob/ob liver also caused a rapid stimulation of long-chain fatty acid synthesis from 13C-labeled acetyl-CoA by the de novo synthesis route. Chronic leptin treatment in vivo induced homeostatic changes that resulted in a tripling of the rate of glycogen synthesis via the gluconeogenic pathway from [2-13C]pyruvate in ob/ob mouse liver perfused in the absence of the hormone. Consistent with the 13C NMR results, leptin treatment of the ob/ob mouse in vivo resulted in significantly increased hepatic glycogen synthase activity. Chronic treatment with leptin in vivo exerted the opposite effect of acute treatment in vitro and markedly decreased hepatic de novo synthesis of fatty acids in ob/ob mouse liver. In agreement with the 13C NMR findings, activities of hepatic acetyl-CoA carboxylase and fatty acid synthase were significantly reduced by chronic treatment of the ob/ob mouse with leptin. Our data represent a demonstration of direct effects of leptin in the regulation of metabolism in the intact functioning liver.     

The effect of phenazine methosulphate on intermediary pathways of glucose metabolism in the lens at different glycaemic levels

In this study changes in alternative pathways of glucose metabolism are examined in the rat lens using radiolabelled glucose in a 1 hr in vitro incubation of 50 mM or 10 mM glucose with or without 0.1 mM phenazine methosulphate (PMS). PMS which reoxidizes NADPH ensures that the pentose phosphate pathway (PPP) is not limited by the supply of NADP+. The data shows that maximal activation of the PPP (with PMS) is 40% greater at high glucose concentrations than normal glucose. This difference in maximal stimulation may be explained by the increase glucose uptake in the hyperglycaemic incubation. In the high-glucose incubation with PMS, hexokinase activity and the glucose 6-phosphate pool is not limiting for the PPP. Under these conditions, PMS alter the NAD+/NADH and NADP+/NADPH ratio. The change in the redox state alters the flux through the polyol pathway, the glycerol 3-phosphate shuttle and the glycolytic control sites, glyceraldehyde 3-phosphate, pyruvate and lactate dehydrogenases. These results are discussed in relation to hyperglycaemia-induced oxidative stress.     

Effects of oral glucose on intermediary metabolism in continuous ambulatory peritoneal dialysis patients versus healthy subjects

AIM OF THE STUDY: Retrospective analysis of result of radical cystectomy at Cochin Hospital. PATIENTS AND METHODS: We report the results of a 106 patients series treated by radical cystectomy for bladder carcinoma after a 5-year period follow-up. RESULTS: The extent of the tumour invasion according to pathological analysis was: pT1 or less: 26%, pT2 and pT3a: 33%, pT3b and over: 41%. Morbidity rate was 19% with a 7.5% reintervention rate. Long term complication rate was 31%, concerning essentially ureteral stenosis. A local recurrence or distant metastasis occurred in 35% of patients. Local recurrence rate was 10.7%. Cancer specific survival rates were 88%, 81% and 42% for pT1, pT2-pT3a, and pT3b patients respectively. CONCLUSION: The present results confirm that radical cystectomy is the most effective curative treatment for invasive bladder carcinoma.     

Notes on the intermediary form of incontinentia pigmenti

In a survey of a representative sample of 900 persons in Switzerland (excluding the Italian speaking parts comprising some 4-5 percent of the population), the smoking habits of the adult population were studied. Smokers were defined as persons smoking at least one cigarette or an equivalent weight of pipe tobacco or cigars per day. 51.8% of men and 29.0% of women over age 15 are smokers. Among male smokers of cigarettes only (42% of all men), over three quarters (77.6%) smoke ten cigarettes or more per day, i.e., a quantity found harmful to health; over one half (55.8%) smoke twenty or more cigarettes per day. Half of all female smokers smoke ten or more cigarettes, more than one in every four female smokers (28.8%) smoke twenty or more cigarettes per day. It is calculated that almost two thirds of all cigarettes sold in Switzerland are smoked by smokers of twenty or more cigarettes per day, and that almost three quarters are smoked by smokers of ten or more cigarettes. Among men, smoking habits are independent of social status, whereas among women, those with higher family incomes show more frequent smoking, but also more widespread cessation of smoking than with lower incomes. Thirty percent of adults having been smokers have given up the habit, so that among men and women above age 15, theree are now some 20% and 14% respectively, of ex-smokers. This corresponds to at least 700,000 former smokers in all of Switzerland. The trend to give up starts already in the group aged 15-24 (over 20% of men and women having ever smoked have given up) and becomes more marked with increasing age. A large part of male and female smokers would like to free themselves of the habit. 30% of male and 34% of female smokers indicate that they had tried seriously to stop smoking during the twelve months preceding the interview. Trying to give up was not significantly associated with intensity of smoking or social status. According to this survey, a majority of the population (57.6%) is in favor of reserving certain parts of restaurants to non-smokers, following the example of non-smokers-compartments in railway trains. In a situation where a non-smoker asks a co-worker in a closed room not to smoke, 78.3% take sides with the non-smoker, either by conceding to him a right to smoke-free air, or by demanding from the smoker to show consideration for the non-smoker. Only 10.9% demand from the non-smoker understanding for the smoker, or concede to the smoker a right to smoke at work. Women show more understanding for cause of the non-smoker than men. This difference is more marked among smokers and former smokers than among non-smokers. Inasmuch as the results of this study are comparable to those of earlier surveys conducted in Switzerland, ther is good agreement. The only exception is a significant increase of the proportion of former smokers in the past years.     

Effect of subtotal thyroidectomy on natural history of ophthalmopathy in Graves'' disease

Metastases to the vagina from breast carcinoma are uncommon, and are most often detected during autopsies of patients who have died from a breast cancer or from metastases to the genital tract. A case of symptomatic vaginal metastasis secondary to bilateral breast carcinoma is reported. The potential routes of dissemination include lymphatic and vascular spread. Their respective frequencies vary in the literature. Lymphatic spread in this case is suggested by demonstrable ovarian, myometrial, and lymph node involvement associated with massive submucosal vaginal involvement. This observation of concomitant visceral and lymphatic spread improves our knowledge of metastatic spread from breast cancer to the female genital tract by the lymphatic route.     

Effect of catechin on carbohydrate metabolism

The serum free carnitine levels of 33 children with recurrent pulmonary infection and 30 healthy children were measured and found to be 26.12 +/- 0.98 nmol/mL and that of the control group 38.98 +/- 0.79 nmol/mL on the average. The mean free carnitine level was statistically determined to be significantly lower when compared with that of the control group (P < 0.01). The results indicate that oral L-carnitine therapy is recommended for pediatric patients with recurrent pulmonary infection.     

Effect of glycerol on triglyceride metabolism in the rat

Lipid metabolic studies were carried out on the male Wistar rats fed on glycerol-rich diet in order to elucidate the mechanism of glycerol-induced hypertriglyceridemia. No difference was found between the glycerol fed rats and the control rats in the rate of triglyceride secretion from the liver measured by the Triton WR-1339 method as well as in the rate of incorporation of labeled glycerol into liver triglyceride. The facts that the half-life of the intravenously injected Intralipid in the blood was significantly delayed in the glycerol fed rats and that the lipoprotein lipase activity released from epididymal adipose tissue of the glycerol fed rats was markedly decreased to 19% of that of the control rats seem to account for the serum triglyceride elevation induced by the glycerol feeding.     

Effect of cyproterone acetate on the testis and epididymis of the lizard, Psammophilus dorsalis (gray)

The effect of cytproterone acetate (CPA) on the testis and epididymis of the lizard, Psammophilus dorsalis has been studied. Treatment with CPA affects spermatogensis and steroid metabolism in the testis. It also causes regression of the epididymis and a decrease in steroidogenic enzyme activity.     

Effect of NIDDM on the kinetics of whole-body protein metabolism

We postulated that dietary protein utilization and body protein metabolism are altered in hyperglycemic individuals with non-insulin-dependent diabetes mellitus (NIDDM). This was tested by estimating the kinetics of protein metabolism in obese NIDDM patients in the hyperglycemic state of isoenergetic feeding and in the normoglycemic state induced by the prolonged use of a very-low-energy diet (VLED) and comparing them with results in obese nondiabetic subjects studied previously. Seven obese subjects with NIDDM (one male, six females, body mass index = 35.8 +/- 2.0 kg/m2) were given a 1.7 MJ (410 kcal) all protein (93 g/day) diet derived from hydrolyzed collagen and supplemented with tryptophan and methionine, which provides 16% of its amino acids as essential, a multivitamin and mineral supplement, and 16 mmol KCl for 42 days. During the seven-day isoenergetic diet and at weeks 4 and 6 of the VLED, amino nitrogen (N) flux rate was calculated from the urine [15N]urea enrichment by using the 60-h oral [15N]glycine method to obtain the integrated feeding-fasting metabolism. Rates of synthesis (S) and breakdown (B) were calculated from N flux. At day 7 of the isoenergetic diet, whole-body N flux, S, B, and resting metabolic rate (RMR) were 12-24% greater (P < 0.05) in the NIDDM subjects than observed in nondiabetic obese subjects. Mean plasma glucose decreased (P < 0.05) from the isoenergetic period (14.9 +/- 2.4 mM) to 7.2 +/- 1.2 mM at week 4 and 6.5 +/- 1.1 mM at week 6 of the VLED. RMR declined progressively by 25% at week 5 of the VLED. Corresponding significant (P < 0.05) decreases from isoenergetic feeding to weeks 4 and 6 of the VLED occurred in whole-body N flux (from 51 +/- 2 to 42 +/- 1 g N/day), in S (from 38 +/- 3 to 24 +/- 1 g N/day), and in B (from 39 +/- 3 to 26 +/- 1 g N/day) resulting in net losses (S-B). S-B was significantly more negative (P < 0.05) in NIDDM than in the nondiabetic obese subjects at week 4 (-1.5 +/- 0.5 vs. 0.9 +/- 0.3 g N/day) but not at week 6 (-1.3 +/- 0.4 vs. -0.9 +/- 4 g N/day). During the VLED, N balance became less negative with time but never reached equilibrium in NIDDM. Thus, abnormal protein metabolism is present in NIDDM in the isoenergetic fed state with moderate hyperglycemia and persists during a VLED that restores glycemia to near normal.     

Effect of tamoxifen on serum lipid metabolism

The effect of tamoxifen, an antiestrogenic agent, on lipid metabolism was studied in postmenopausal patients with breast cancer who received the drug for postoperative adjuvant treatment following mastectomy. To measure total cholesterol and triglyceride concentrations, fasting blood samples were collected before and 2 months after the initiation of tamoxifen therapy from 16 patients who satisfied the study criteria. All patients were normolipidemic before tamoxifen was administered. Control samples were obtained from hypertriglyceridemia patients who were free from breast cancer. Marked hypertriglyceridemia was observed in 3 of 16 patients after tamoxifen treatment. The activity of lipoprotein lipase and hepatic triglyceride lipase, the key enzymes of triglyceride metabolism, decreased significantly in all of 16 patients as a result of tamoxifen treatment (P = 0.008 and P = 0.007, respectively). However, the mean mass of lipoprotein lipase significantly increased (P = 0.011) after tamoxifen treatment. We therefore conclude that tamoxifen might increase inactive lipoprotein lipase. Because marked hyperlipidemia is a potent risk factor for life-threatening acute pancreatitis and arteriosclerosis, plasma lipid levels should be tested periodically during tamoxifen treatment, even if the patients are normolipidemic during the pretreatment stage.     

Effect of prolactin on metabolism of human spermatozoa

The effect of prolactin on adenyl cyclase, rate of fructose utilization, and glucose oxidation by human spermatozoa was studied. Prolactin stimulated all of these processes at a concentration generally available in seminal plasma. These results suggest that prolactin plays an important role in the energy metabolism of human spermatozoa.     

Effect of theophylline on substrate metabolism during exercise

We tested the hypothesis that adenosine is involved in regulating substrate metabolism during exercise. Seven trained cyclists were studied during 30 minutes of exercise at approximately 75% maximal oxygen uptake (VO2max). Lipid metabolism was evaluated by infusing [2H5]glycerol and [1-13C]palmitate, and glucose kinetics were evaluated by infusing [6,6-2H]glucose. Fat and carbohydrate oxidation were also measured by indirect calorimetry. The same subjects performed two identical exercise tests, but in one trial theophylline, a potent adenosine receptor antagonist, was infused for 1 hour before and throughout exercise. Theophylline did not increase whole-body lipolysis (glycerol rate of appearance [Ra]) or free fatty acid (FFA) release during exercise, but fat oxidation was lower than control values (9.5 +/- 3.0 v 18.0 +/- 4.2 micromol x min(-1) x kg(-1), P < .01). Glucose Ra was not affected by theophylline infusion, but glucose uptake was lower (31.6 +/- 4.1 v 40.4 +/- 5.0 micromol x min(-1) x kg(-1), P < .05) and glucose concentration was higher (6.4 +/- 0.6 v 5.8 +/- 0.4 mmol/L, P < .05) than in the control trial. Total carbohydrate oxidation (302.3 +/- 26.2 v 265.5 +/- 11.7 micromol x min(-1) x kg(-1), P < .06), estimated muscle glycogenolysis (270.7 +/- 23.1 v 225.1 +/- 9.7 micromol x min(-1) x kg(-1), P < .05), and plasma lactate concentration (7.9 +/- 1.6 v 5.9 +/- 1.1 mmol/L, P < .001) were also higher during the theophylline trial. These data suggest that adenosine may play a role in stimulating glucose uptake and restraining glycogenolysis but not in limiting lipolysis during exercise.     

Effect of high performance sports on energy metabolism

The knowledge about metabolism and muscular fatigue has been considerably improved during the recent years. Intramuscular pH should not generally be discussed as a factor of cellular fatigue as it has been shown to increase transiently at the beginning and to be very differently affected in ST-(6,9) and FT-fibers (6,2) at the end of exercise. During maximum exercise, we assume changes of muscle membrane potential due to increasing interstitial potassium concentrations as an important performance-limiting factor. The role, lactate is playing during exercise, has to be thought over. Its production by the binding of two protons to the pyruvate molecule is necessary for an intensive anaerobic and aerobic metabolism. The lactate molecules itself represent a source of energy, which is preferentially used by the heart muscle and by ST-fibers working at lower intensity. During long term endurance events, the glycogen stores are assumed to be a limiting factor. However, no direct casual relationship between glycogen and fatigue mechanisms has been found hithertoo. The anaerobic glycolytic metabolism decreases during long lasting exercise as a result of lowered glycogen stores. Therefore, metabolic acidosis cannot be observed after ultra-long endurance events. In contrast, a respiratory alcalosis is the common finding.     

Effect of monensin on rumen metabolism in vitro

The effect of Monensin (Rumensin, Eli Lilly & Co.) in incubations with mixed rumen microorganisms metabolizing carbohydrate or protein substrates was investigated. Monensin partly inhibited methanogenesis and increased propionate production, although the effect was not always statistically significant. Incubations with substrates specific for methane bacteria suggest that inhibition of methanogenesis by Monensin was not due to a specific toxic action on the methanogenic flora, but rather to an inhibition of hydrogen production from formate. Total and net microbial growth were considerably decreased by addition of Monensin, although the amount of substrate fermented was not altered, resulting in lowered values of microbial growth efficiency. In incubations with casein, Monensin lowered protein degradation in line with a lowered ammonia production, whereas a slight accumulation of alpha-amino nitrogen was observed. The results suggest that besides an influence of Monensin on the rumen carbohydrate fermentation pattern, another reason for the beneficial effects observed in vivo might be decreased food protein degradation in the rumen, altering the final site of protein digestion in the animal. Also, the possibility of a decrease in rumen microbial growth efficiency has to be considered when using Monensin as a food additive.