Spatiotemporal expression patterns of doublesex and mab-3 related transcription factor 1 in the chicken developing gonads and Mullerian ducts.

Sex of birds is genetically determined by the inheritance of sex chromosomes (ZZ for male and ZW for female), and the Z-linked gene named doublesex and mab-3 related transcription factor 1 (DMRT1) is a candidate sex-determining gene in avian species. However, the mechanisms underlying sex determination in birds are not yet understood, and the expression patterns of the DMRT1 protein in urogenital tissues have not been identified. In the current study, we used immunohistochemistry to investigate the detailed expression patterns of the DMRT1 protein in the urogenital systems (including Müllerian ducts) in male and female chicken embryos throughout embryonic development. Gonadal somatic cells in the male indifferent gonads showed stronger expressions of DMRT1 compared with those in the female indifferent gonads well before the presumptive period of the sex determination, and Sertoli cells forming testicular cords expressed DMRT1 in the testes after sex determination. Germ cells expressed DMRT1 equally in males and females after sex determination. The expression was continuous in males, but in females it gradually disappeared from the germ cells in the central part of the cortex of the left ovary toward both edges. The DMRT1 was also detected in the tubal ridge, which is a precursor of the Müllerian duct, and at the mesenchyme and outermost coelomic epithelium of the Müllerian duct in both sexes. Strong expression was observed in the males, but it was restricted to coelomic epithelium after the regression of the duct started. Thus, we observed the detailed spatiotemporal expression patterns of DMRT1 in the developing chicken urogenital systems throughout embryonic development, suggesting its various roles in the development of urogenital tissues in the chicken embryo.

Hemodynamic stabilizing effects of L-carnitine in chronic hemodialysis patients.

BACKGROUND: The effects of L-carnitine on the hemodynamic state of chronic hemodialysis patients have been debated. In order to clarify the effect of administered L-carnitine on cardiac function and hypotensive episodes during the hemodialysis procedure, a randomized double-blind placebo-controlled study was performed for 3 months. METHODS AND RESULTS: TWENTY STABLE OUTPATIENTS UNDERGOING HEMODIALYSIS TREATMENT WERE DIVIDED INTO TWO GROUPS: controls (placebo) and treated patients (L-carnitine 900 mg p.o. daily). After 3 months, cardiac function was reevaluated by echocardiography, and hypotensive episodes during hemodialysis were assessed. Free and acyl carnitine levels increased significantly from 22.3 ± 7.1 to 140.3 ± 57.5 µmol/l and from 15.8 ± 2.8 to 94.8 ± 50.4 µmol/l, respectively, in the treated group. The ejection fraction significantly increased from 61.8 ± 16.0 to 64.4 ± 13.8% (p < 0.05) in the treated group. However, there was no difference in other echocardiographic parameters between the two groups. Hypotensive episodes significantly decreased from 4.0 ± 1.7 to 1.3 ± 0.9 times per month (p < 0.05), although patients' body weight did not change significantly. CONCLUSIONS: Beneficial effects of L-carnitine on the hemodynamic state of chronic hemodialysis patients were observed. L-Carnitine supplementation might be considered especially for chronic hemodialysis patients with unstable hemodynamic conditions.

Prevalence of asymptomatic ST segment elevation in right precordial leads with right bundle branch block (Brugada-type ST shift) among the general Japanese population.

OBJECTIVE: To examine the modality and morbidity of asymptomatic ST segment elevation in leads V1 to V3 with right bundle branch block (Brugada-type ST shift). METHODS: 8612 Japanese subjects (5987 men and 2625 women, mean age 49.2 years) who underwent a health check up in 1997 were investigated. Those with Brugada-type ST shift underwent the following further examinations over a two year period after the initial check up: ECG, echocardiogram, 24 hour Holter monitoring, treadmill exercise testing, signal averaged ECG, and slow kinetic sodium channel blocker loading test (cibenzoline, 1.4 mg/kg). RESULTS: Asymptomatic Brugada-type ST shift was found in 12 of 8612 (0.14%) subjects. Eleven of these 12 subjects were followed up. Follow up ECG exhibited persistent Brugada-type ST shift in seven of 11 (63.6%) subjects. ST shift was transformed from a saddle back to a coved type in three subjects. None of the subjects had morphological abnormalities or abnormal tachyarrhythmias. Positive late potentials were found in seven of 11 (63.6%) subjects. Augmentation of ST shift was shown by both submaximal exercise and drug administration in one of the 11 subjects (9.1%). CONCLUSIONS: Asymptomatic subjects with Brugada-type ST shift were not unusual, at a rate of 0.14% in the general Japanese population. Almost all of the subjects had some abnormalities in non-invasive secondary examinations. Additional and prospective studies are needed to confirm the clinical significance and the prognosis of asymptomatic Brugada-type ST shift.