Vitamin B12 treatment for delayed sleep phase syndrome: A multi-center double-blind study

Abstract  The active form of vitamin B₁₂ (methylcobalamin) has been reported to be effective on sleep-wake rhythm disorders. Previous studies, however, were performed under open trial, and the effect of vitamin B₁₂ has not been properly evaluated. The aim of this double-blind study was to investigate the efficacy of methylcobalamin on delayed sleep phase syndrome (DSPS). Methylcobalamin (3 mg/day) or placebo was administered for 4 weeks. The subjects were 50 patients with DSPS aged 13–55 years (26.8 ± 1.3), 27 of whom received the active drug while 23 received the placebo. No significant differences were observed between the 2 groups in subjective evaluations of mood or drowsiness during the daytime or in night sleep by sleep-log evaluation. These results indicate that 3 mg methylcobalamin administered over 4 weeks is not an effective treatment for DSPS.     

α-Helix structure of parathyroid hormone fragment (1–34) predicted by Monte Carlo simulated annealing

Tertiary structure of parathyroid hormone fragment (1–34) is predicted by the Monto Carlo simulated annealing method. Among the 20 structures obtained after completely unbiased calculations, the lowest-energy conformation exhibits two α-helices around residues 2–10 and 18–22. This structure agrees with the models, especially with the location of helices, deduced from experiments. In addition, the simulation supports empirical implications in the following two points. (1) The helix near the N-terminus is more stable than the C-terminal one. (2) The rest of the peptide segments are flexible and do not tend to have any definite structure. Our calculation correctly predicts only an α-helix, whereas previous analyses by the Chou–Fasman method leave an ambiguity between an α-helix and a β-strand.     

Effect of night exercise on the following partially deprived sleep

Abstract Six trained male athletes (aged 24.3 ± 2.9 years) performed cycling exercise from 23.00 to 23.50 h. From 00.30 to 07.00 h, the subjects followed a schedule that consisted of 30 min trying to fall asleep in bed and 60 min of being awake outside the bedroom. The control experiment was conducted without exercise under the same time schedule. An increase in rectal temperature induced by exercise was 1.9 ± 0.4. After exercise, prolongation of sleep onset latency was observed only in the sleep period from 00.30 to 01.00 h compared with the control night. Time spent in slow wave sleep throughout the night was significantly longer after exercise.     

Frequency of Spontaneous Axial Skeletal Variations Detected by the Double Staining Technique for Ossified and Cartilaginous Skeleton in Rat Fetuses

The purpose of the present study was to determine the frequency of spontaneous axial skeletal variations detectable by the double staining technique in Crj: CD (SD) and Crj: Wistar rat fetuses. In addition, the frequencies of unossified skeletal variations were compared between SD and Wistar rats, and between same strain male and female rat fetuses. Fifteen types of the variations were detected. There were strain differences (4 types) and sex differences (3 types) in the frequencies of the variations. With the aid of double staining technique, skeletal variations such as supernumerary ribs or deformed ossification centers detected by the single staining technique could be classified in detail into many types. This study showed that the double staining technique improved detectability of skeletal variations and facilitated their evaluation in developmental toxicity studies.     

α1-adrenoceptor stimulation is able to reverse halothaneinduced cardiac depression in isolated rat hearts

Background: Stimulation of myocardial α₁-adrenoceptors has been shown to exert positive inotropic effects through a cyclic AMP-independent mechanism. The purpose of this study was to examine if α₁-adrenoceptor stimulation is able to attenuate myocardial depression produced by exposure to halothane, and to test if α₁-adrenoceptor stimulation alters myocardial oxygen supply-demand balance in hearts exposed to halothane.
Methods: The effects of phenylephrine were examined in 7 isolated perfused rat hearts. Variables measured were: heart rate, isovolumetric peak left ventricular pressure (LVP), LV dP/dt, coronary arterial flow, myocardial O₂ delivery (DO₂), myocardial O₂ consumption (MVO₂) and the ratio of DO₂/MVO₂. Each heart was exposed to phenylephrine cumulatively 0.1 μM, 0.3 μM, 1 μM and 3 μM under the administration of 1% halothane in the presence of propranolol 1μM.
Results: Halothane 1% decreased the heart rate by 9±3%, LVP by 37±3%, and LV dP/dt by 35±2%. Phenylephrine restored these decreases to the baseline levels. Phenylephrine maintained or further enhanced the reductions in coronary flow and DO₂ produced by halothane, resulting in a decrease in the DO₂/ MVO₂ ratio.
Conclusion: α₁adrenoceptor stimulation is capable of restoring direct cardiac depressant effects of halothane with a possible impairment of the oxygen supply-demand balance.     

抗艾滋病细胞株的交叉耐性及抑制细胞凋亡

目的 体外研究奈非那韦耐性细胞株对其它抗艾滋病药及抗癌药的反应及与细胞7周亡的关系。方法 通过将成人T细胞白血病细胞株Jurkat培养于含有奈非那韦浓度不断增加直至14μm的培养液中培养50d以获得耐奈非那韦的亚系细胞株Jurkat^TN。药敏试验用四唑嗡染色法(类似XTT法)并用流式细胞仪检测抗7周亡蛋白Bcl-2在母本和耐性Jurkat细胞中的表达。结果 发现Jurkat^TN细胞对d4T及新近报道的抗艾滋病药K-37的交叉耐性与母本细胞相比提高到5倍左右。对抗肿瘤药CDDP，VCR，DOX和VP-16的交叉耐性也提高到2．5倍以上。并且耐性细胞中心Bcl-2蛋白的荧光密度增加。结论 在用HIV-1蛋白酶抑制物奈非那韦作用后，Jurkat细胞对其它抗艾滋病药及抗肿瘤药产生了交叉耐性并且抗凋亡蛋白Bcl-2的表达增加。     

Synthesis of peptide inhibitors of human spleen fibrinolytic proteinase (SFP) and human leukocyte elastase-like proteinase (ELP)

Stereoisomers of specific substrates for SFP and ELP, Suc-L-Tyr-L-Leu-L-Val-pNA and Suc-L-Ala-L-Tyr-L-Leu-L-Val-pNA, were synthesized by the conventional solution method. Suc-L-Tyr-D-Leu-D-Val-pNA was found to be an effective and specific inhibitor of SFP and ELP. Suc-L-Tyr-L-Leu-L-Val-Pipe and Suc-L-Tyr-D-Leu-D-Val-Pipe inhibited only SFP very slightly and showed no inhibitory effect on ELP. Both Dan-L-Tyr-L-Leu-L-Val-pNA and Dan-L-Tyr-D-Leu-D-Val-pNA exhibited an inhibitory effect on both SFP and ELP.     

Ejaculated spermatozoa in patients with non‐mosaic Klinefelter’s syndrome

Background : Non‐mosaic Klinefelter patients are generally azoospermic and there is no therapy to improve the spermatogenesis. Some patients have a few spermatozoa in their ejaculates, which can be used for intracytoplasmic sperm injection (ICSI), but only a few cases resulting in a successful birth have been reported. Methods : Out of 52 non‐mosaic 47,XXY Klinefelter patients, four cases having spermatozoa in their ejaculates were retrospectively studied. Results : Intracytoplasmic sperm injection was performed in three cases using their ejaculates and resulted in one chemical abortion and one death in utero (8 weeks). Using testicular sperm, one patient had a healthy baby with a normal karyotype. Conclusion : Some non‐mosaic Klinefelter patients have ejaculated sperm that can result in a successful birth following ICSI. However, the birth rate is very low compared with the fertilization rate, suggesting increased risk of chromosomal abnormalities.     

Gender differences in the sleep of middle-aged individuals

Abstract The study was designed to investigate gender differences in the sleep-wake patterns of healthy middle-aged individuals in their home environment. Polysomnography showed that daytime napping was more common in men than in women. Men had lower sleep efficiency index and experienced more stage 1 sleep. Males had significantly less stages 3 + 4 sleep, less stage REM sleep, and more transitions to wake from REM sleep. Men could not maintain stage REM as well as women. This study indicates that the gender differences in the sleep-wake patterns have appeared in a group of middle-aged individuals.