Catalase enzyme mutations and their association with diseases.

Enzyme catalase seems to be the main regulator of hydrogen peroxide metabolism. Hydrogen peroxide at high concentrations is a toxic agent, while at low concentrations it appears to modulate some physiological processes such as signaling in cell proliferation, apoptosis, carbohydrate metabolism, and platelet activation. Benign catalase gene mutations of 5' noncoding region (15) and intron 1 (4) have no effect on catalase activity and are not associated with disease.Catalase gene mutations have been detected in association with diabetes mellitus, hypertension, and vitiligo. Decreases in catalase activity in patients with tumors is more likely to be due to decreased enzyme synthesis rather than to catalase mutations.Acatalasemia, the inherited deficiency of catalase has been detected in 11 countries. Its clinical features might be oral gangrene, altered lipid, carbohydrate, homocysteine metabolism and the increased risk of diabetes mellitus. The Japanese, Swiss, and Hungarian types of acatalasemia display differences in biochemical and genetic aspects. However, there are only limited reports on the syndrome causing these mutations.These data show that acatalasemia may be a syndrome with clinical, biochemical, genetic characteristics rather than just a simple enzyme deficiency.     

Magnesium-orotate supplementation for idiopathic infertile male patients: a randomized, placebo-controlled clinical pilot study.

A randomized, placebo-controlled clinical pilot study was performed in order to examine the effect of magnesium-orotate in male idiopathic infertility. Ten males were treated daily for 90 consecutive days with 3000 mg magnesium-orotate (Magnerot) tablets (Group M). As a control, ten other males were treated in the same way with placebo (Group P). Conventional microscopic sperm characteristics (sperm concentration, motility ratio, total number of motile sperm cells, normal morphology ratio), plus total and ionized magnesium levels in seminal plasma and blood serum were evaluated both prior to treatment and on day 90, at the conclusion of the study. No significant changes in sperm characteristics, blood ionized or total Mg, or ejaculate total Mg levels were detected. However, ejaculate ionized Mg levels increased in Group M from 0.18 +/- 0.05 to 0.30 +/- 0.05 (mmol/l; mean +/- SD, p < 0.05). Within the observation period of 3 months, one pregnancy occurred in the partner of a male from Group M. In conclusion, magnesium-orotate treatment at a dose of 3000 mg/day leads neither to a significant improvement of sperm variables nor does it increase the pregnancy rates of female partners of treated males as compared to those of controls. Thus, magnesium-orotate treatment was not shown to be effective therapy for idiopathic male infertility.     

Melatonin reduces nitric oxide synthase activity in rat hypothalamus

Abstract: In this report, rat hypothalamic nitric oxide synthase (NOS) activity is shown to be partially inhibited by physiological concentrations of the pineal hormone melatonin. In vitro studies demonstrate that 1 nM melatonin, which approximates the physiological concentration of the hormone at night, significantly inhibited NOS activity. In vivo studies show that administering melatonin or collecting the hypothalamus from animals at night, when endogenous melatonin levels are elevated, results in a significant decrease of NOS activity. Results also show that calmodulin may be involved in this process since its presence in the incubation medium prevents the inhibitory effect of melatonin on NOS activity.     

Time course of superoxide generation by leukocytes—The MCLA chemiluminescence system

This study was performed to examine the pattern of Superoxide (O ₂ ^– ·) generation from leukocytes using the O ₂ ^– · specific chemiluminescence (CL) method.Cypridina luciferin analog, 2-methyl-6-(p-methoxyphenyl)-3,7-dihydroimidazo[1,2-alpha]pyrazin-3-one (MCLA) was used as a CL probe. The appropriate conditions of the MCLA method was first determined for the evaluation of the time course of O ₂ ^– · generation by leukocytes. The time course of O ₂ ^– · generation obtained by the MCLA-CL system was compared with that by the luminol-dependent CL, electron spin resonance (ESR)/spin trapping, and cytochromec systems. Following stimulation by three different stimulants (PMA, OZ, FMLP), leukocytes continuously generated O ₂ ^– · for up to 5 h in the MCLA-CL system, irrespective of the kind of stimulation. The curves obtained by generation ceased more rapidly in the luminol-CL, ESR/spin trapping, and cytochromec systems. A 50% activity of the initial value was observed at 70 min in the MCLA-CL system, but 30, 10 and 35 min in the other systems, respectively. The CL or O ₂ ^– · generation value decreased to less than 1% (possible termination) at 300, 90, 120 and 180 min, respectively. With the exception of ESR studies with OZ, the cell viability was not significantly affected in any of the trials. These results indicate that leukocytes can generate O ₂ ^– · much longer than previously estimated and that the MCLA-CL-system is the most suitable system for the measurement of the O ₂ ^– · generation by leukocytes.     

Endoscopic stapling diverticulotomy: an audit of difficulties, outcome, and patient satisfaction.

OBJECTIVE: To evaluate the procedure in terms of technical difficulties, patient satisfaction, symptom relief, recurrence, and further management. STUDY DESIGN: Retrospective study including 41 patients who underwent endoscopic stapling diverticulotomy. Clinical notes were reviewed, and patients were sent a patient satisfaction questionnaire. Statistical analysis was done using the chi(2) square test. SETTING: Teaching hospital. RESULTS: Larger pouches had the best results; 81.578% were satisfied with the surgery, and 86.84% had improved swallowing. Complications presented in 6 patients (15%), including a perforated pouch and an esophageal perforation. Complications were more frequent in small pouches. CONCLUSIONS AND SIGNIFICANCE: Endoscopic stapling diverticulotomy offers rapid recovery in most patients, with early oral intake and short hospital stay. There is a high degree of symptoms relief, and the patient's satisfaction rate is high. The assessment of the pharyngeal pouch size is an important factor when deciding the best management for a patient with a pharyngeal pouch.     

Cast syndrome

The term cast syndrome is used to denote duodenal obstruction occurring after application of a corrective plaster cast to patients with scoliosis. We report a classical case in a 14-year-old female who required surgical intervention after conservative treatment failed. Six months later the patient had no further gastrointestinal symptoms. Clinical, radiological, and pathological details as well as the surgical treatment are described and discussed. Offprint requests to: M. E. Martín Hortigüela