An automatic device for single-breath CO diffusing capacity in dogs

Summary We describe a very simply operated system by which single-breath CO diffusing capacity (D_LCO) can be measured in anesthetized dogs.All controls and the automatic system are operated pneumatically. Cams forming an integral part of the pistons of the inspiratory and experatory syringes activate push buttons which control the valves, enabling dead spaces to be flushed, a specific volume of air to be injected into the dog's lungs, and expiratory samples to be taken.Our results, due account being taken of the dogs' weight, are in the upper range of normal values published in earlier studies; the reproducibility of the method is good.     

Effects of Pure Chlorobiphenyls (2,4′,5-Trichlorobiphenyl and 2,2′,4,4′,5,5′-Hexachlorobiphenyl) on the Reproductive Capacity in Female Mice

Abstract The effects of two pure chlorobiphenyls (2,4′,5-trichlorobiphenyl and 2,2′,4,4′,5,5′-hexachlorobiphenyl) on the reproductive capacity in female mice have been studied. The results obtained show that females given 0.5 mg 2,4′,5-trichlorobiphenyl (TCB)/day or 0.5 mg 2,2′,4,4′,5,5′-hexachlorobiphenyl (HCB)/day for six consecutive days, starting on the first day of pregnancy, have significantly lower frequencies of implanted ova than the control females, whereas the frequency of implanted ova does not differ either between females given 0.05 mg/day of TCB or HCB and the control females, or between females given TCB 0.05 mg/day or 0.5 mg/day and those given the corresponding dose of HCB. Females given 0.5 mg/day of TCB or HCB, respectively, also have significantly higher contents in the livers of cytochrome P-450, on Day four of pregnancy, than the control females. The results also show that, under the experimental conditions used, neither the frequency of pregnancies nor the number of implanted ova per pregnant female differ significantly between the different groups.     

Influence of hepatic impairment on the pharmacokinetics of nefazodone and two of its metabolites after single and multiple oral doses

Summary— The pharmacokinetics of nefazodone, a new antidepressant, and two of its active metabolites, hydroxynefazodone and m-chlorophenylpiperazine, were determined after single and repeated oral escalating doses of 50, 100 and 200 mg, in healthy volunteers ( n = 13) and patients with mild ( n = 13) or severe ( n = 6) hepatic impairment. All subjects were classified according to their dextromethorphan oxidation capacity. In healthy volunteers, nefazodone was rapidly absorbed after which the plasma concentrations declined with an apparent elimination half-life ranging from 2.7 ± 1.7 h to 10.2 ± 4.4 h according to the dosage. Hydroxynefazodone appeared rapidly in plasma and its time-course (half-life ranging 1.4 ± 0.9 h to 6.5 ± 1.6 h) paralleled that of nefazodone, while mCPP showed low and variable concentrations. The disproportionately longer half-life and more markedly increased C_max and AUC_0–48 which was observed with dosage and treatment duration, and moreover AUC_0–12 at steady state significantly higher ( P < 0.05) than AUC_0–∞ after single dose demonstrated the non-linearity of the pharmacokinetics of nefazodone and hydroxynefazodone. The constant molar AUC_0–48 hydroxy-nefazodone/nefazodone ratio (0.32 ± 0.04) and the close correlation ( r ² = 0.95) between kinetic parameters of nefazodone and hydroxynefazodone suggest that nefazodone hydroxylation is not a saturable process. The kinetics of nefazodone and metabolites were significantly affected by severe but not by mild liver insufficiency. As a consequence, on a pharmacokinetic basis nefazodone should be used with caution in severely hepatic impaired patients.     

Reference values for renal concentrating capacity in children by the desmopressin test

Reference values are reported for maximal renal concentrating capacity in children using intranasally administered desmopressin. The report is based on 591 tests in 473 healthy children aged 0.5–13 years. The concentrating capacity increased markedly during the first years of life and reached a plateau at the age of 3 years. The mean value minus two standard deviations was 525 mosmol/kg at 1 year of age and 825 mosmol/kg at 3 years of age.     

Maximal hemodynamic response after the Fontan procedure: Doppler evaluation during the treadmill test

Summary After undergoing the Fontan procedure for congenital heart disease, 16 young patients performed a maximal treadmill test according to the Bruce protocol. The peak velocity of the blood flow in the ascending aorta, stroke index, and cardiac index were measured by continuous-wave Doppler echocardiography at rest and at each stage of the test. The results were compared with those from 18 normal children. The body surface area was similar in the two groups. The endurance time was 37% shorter in the Fontan group than in the control group. From the beginning of exercise until the sixth minute, the increase in stroke index was lower in the Fontan group (NS). After that point, the stroke index was maintained at a high level in the control group but decreased toward its original level in the Fontan group. The response of cardiac index to exercise in the two groups was comparable until the sixth minute, after which the Fontan group failed to maintain an ascending curve. All the hemodynamic values were significantly higher in the control group at maximal exercise; at this point the cardiac index had increased 79% in the Fontan group and 170% in the control group. The subnormal response of the stroke volume at submaximal exercise and the subsequent decrease at maximal exercise following the Fontan procedure are important hemodynamic findings.     

Comparative study on the use of human follicular fluid or egg yolk medium to enhance the performance of human sperm in the zona-free hamster oocyte penetration assay

A prospective study was conducted on 61 unselected semen samples from infertile patients to compare the efficacy of human follicular fluid (hFF) or TEST-egg yolk medium treatment in enhancing sperm performance in the zona-free hamster oocyte penetration (HOP) test. Both hFF and TEST-egg yolk enhanced penetration scores significantly in the HOP test in comparison with the control swim-up sperm preparation. The TEST-egg yolk medium treatment, however, exhibited the highest penetration scores, and there were higher percentages of preparations passing the 10 or 20% penetration rate cut-off point with sperm exposed to the TEST-egg yolk medium than those exposed to hFF. These results indicate that modification of the original HOP-test protocol by incorporation of TEST-egg yolk medium gives a greatly increased penetration rate when compared to the addition of hFF in such a system.     

提高高原劳动能力方案效果的评估研究

将９９名生活在海拔３６８０ｍ高原１年以上的健康男性受试者随机分为三组，分别接受锻炼（Ａ）、口服中成药（Ｂ）、以及既服中成药又锻炼（Ｃ）三种不同方案处理，以自身对照的方法测量其接受处理前后的体能指标和心血管指标。结果显示，接受处理后，其体能明显增强，并且循环系统指标的变化显示了其心脏功能和微循环的改善。研究结果还表明，Ａ、Ｂ、Ｃ三种方案均能改善体循环以抵抗缺氧，增强劳动能力。