复方天棘胶囊对老龄鼠血气影响的研究

本研究选用昆明种老龄鼠５０只，随机分为正常对照组、阳性对照组和复方天棘胶囊高、中、低剂量组；每组１０只。观察灌服复方天棘胶囊溶液对实验性老龄鼠血气的影响。结果表明，老龄鼠灌服２．０、１．０和０．５ｇ／ｋｇ体重复方天棘胶囊溶液及５．０ｇ／ｋｇ体重红参水煎液１０天后，复方天棘胶囊各剂量组均有不同程度的升高动脉血氧分压（ＰａＯ＿２）和血氧饱和度（ＳａＯ＿２）的作用；且随剂量的递增，ＰａＯ＿２和ＳａＯ＿２明显升高，其中高剂量组升高ＰａＯ＿２和ＳａＯ＿２的作用最为明显（Ｐ＜０．０１）；红本组ＳａＯ＿２也有明显升高（Ｐ＜０．０１）。提示复方天棘胶囊具有升高ＰａＯ＿２和ＳａＯ＿２的作用。     

Chlorocarbamate-mustard-linked 1,1,2-triphenylbut-1-enes with a selective antitumor activity on mammary tumors containing estrogen receptors

Summary A 1,1,2-triphenylbut-1-ene with a 4-OH group at one C-1 phenyl ring and a chlorocarbamate mustard moiety at the second C-1 ring (compound 3) was synthesized in order to obtain a cytotoxic estrogen with a specific antitumor effect on estrogen-receptor-containing tumors. This compound was tested in comparison to the carrier (compound 1) and a compound (2) having a carbamate mustard group on both C-1 phenyl rings. The estrogen receptor affinity of compound 3 was only about one-quarter lower than that of compound 1, but much higher than that of compound 2. Compounds 2 and 3 showed only partially irreversible binding to the receptor owing to their relatively low alkylating properties. The growth inhibition of the receptor-positive MCF-7 breast cancer cell line by compound 3, but not by compound 1 or 2, was more pronounced than the inhibition of the receptor-negative line MDA. In vivo the hormone-dependent, transplantable mammary tumor MXT M3.2 of the mouse was much better inhibited by compound 3 than its hormone-resistent line MXT OVEX. Compounds 1–3 had no antiestrogenic properties in the mouse, but estrogenic activity was in the order 1>3>2. From these results and because the antitumor activity of compound 3 was superior to that of compounds 1 and 2 in the hormone-dependent tumor models, a selective, receptor-mediated cytotoxic effect of compound 3 on estrogen-receptor-positive tumors in obvious.Supported by the Deutsche Forschungsgemeinschaft, SFB 234 and the Matthias Lackas StiftungDedicated to Prof. Dr. M. F. El Etreby on the occasion of his 50th birthday     

Pump for accurate mixing of three gas components with predetermined fractions

A mixing pump that creates an accurate mixture of three gases at predetermined fractional ratios that can be set in steps of 10 ppm is described. A nearly continuous flow of each of the three component gases is produced by pistons driven by stepping motors; the gas mixture is forwarded by a fourth piston. The flow of each component gas is adjusted by the stepping frequency of the motor and a microcomputer system is used to adjust the three frequencies according to the desired fractional concentrations. The total flow of the gas mixture is adjustable between 0.1–500 ml/min and is nearly independent of the after-load. The accuracy of the pump was tested by mixing the respiratory gases, O₂ and CO₂, with various carrier gases (N, He or Ar) at various fractional ratios and total flow rates. The fractions of O₂ and CO₂ in the mixture were analysed with the Scholander technique. In the physiological range, the mixing error in the gas fractions was less than 4%. The pump is, thus, suited for producing calibration mixtures.     

Activity of the human carcinogen MeCCNU in the mouse bone marrow micronucleus assay

The nitrosourea mustard MeCCNU is the most recent organic chemical to be classified as a human carcinogen by IARC. MeCCNU gave a strong positive response when tested in the mouse bone marrow micronucleus assay. Activity was evident using either ip injection or oral gavage of the test chemical. These results further support the correlation between human carcinogens and their genotoxicity.     

Rapid hydroxylation of methtryptoline (1-methyltetrahydro-β-carboline) in rat: Identification of metabolites by chiral gas chromatography-mass spectrometry

Summary Racemic methtryptoline (1-methyltetrahydro--carboline) and 5-hydroxymethtryptoline-9-carboxylic acid (6-hydroxy-1-methyltetrahydro--carboline-1-carboxylic acid) were administered intraperitoneally to rats and the components of their urine was subsequently investigated by chiral gas chromatography-mass spectrometry. Methtryptoline rapidly became hydroxylated in the 5- and 6-position and excreted in urine. There was about a ninefold predominance of the S(–) enantiomer over the other in the 5-hydroxylated species, while the 6-hydroxylation produced a small excess of the R(+) enantiomer. About 75% of the injected dose of methtryptoline was recovered in the urine as 5- and 6-hydroxylated compounds during the first 24 h period, demonstrating that hydroxylation represents the major metabolic pathway. Treatment with 6-hydroxymethtryptoline-9-carboxylic acid led to a fivefold increase in the urinary excretion of 5-hydroxymethtryptoline during the first 24 h period with a predominance of the S(–)-enantiomer, indicating a much smaller conversion rate than from methtryptoline. It was concluded that hydroxylation of methtryptoline is a likely pathway for the natural formation of 5-hydroxymethtryptoline.     

Rapid isolation of some antiepileptic hydantoins and their analogues with Sep-Pak C18 cartridges and capillary gas chromatography with splitless injection

Summary A simple and rapid method for isolation of seven antiepileptics (2 hydantoin, 2 oxazolidin, and 3 suximide derivatives) from urine and plasma is presented. Urine and plasma (1 ml) samples containing seven antiepileptics were mixed with distilled water (4 ml), and the sample solution was poured into a pretreated Sep-Pak C₁₈ cartridge; this was washed with water and chloroform/methanol was passed through it to elute the antiepileptics. The eluate was mixed with isoamyl acetate and evaporated under a stream of N₂. The drugs were detected by gas chromatography with fused silica capillary columns, splitless injection and flame ionization detection. Separation of the seven antiepileptics from each other and from impurities was satisfactory with the use of an SPB-1 capillary column. The detection limit for the seven antiepileptics with the present method was 0.1–1.0 g/ml urine or plasma. The recovery of the drugs from urine and plasma was more than 70% and 50%, respectively. Offprint requests to: O. Suzuki     

Does calcium balanced heparin affect blood gas and electrolyte analysis?

The effect of calcium-balanced heparin (471896, CIBA CORNING) on blood gas and electrolyte analysis was evaluated, by comparing with that of sodium heparin (Na heparin). One ml of whole blood was collected into a syringe, which contained calcium-balance heparin (Ca balanced heparin) or Na heparin. 122 pairs of blood samples obtained from 15 patients were analyzed for Na, K, ionized calcium (Ca(++)), total hemoglobin, pH, P(CO)(2), and P(O)(2) by an automatic blood gas and electrolyte analyzer, CIBA CORNING model 288. There was a significant difference ( P < 0.05) in pH, P(CO)(2), Na, and Ca(++) between the two different groups. Ca(++) concentration was significantly less in Na heparin group than in Ca balanced heparin group, probably due to more chelation of Ca(++) by Na heparin than Ca balanced heparin. The present study suggests that the Ca balanced heparin has minimal effect on the blood gas and electrolyte analysis, and is a suitable anticoagulant for the Ca(++) measurement.     

A clinical comparison of indices of pulmonary gas exchange with changes in the inspired oxygen concentration

Several indices have been introduced as convenient alternatives to calculation of the physiological shunt fraction (Qs/QT) for the assessment of pulmonary gas exchange. These include: the arterial-alveolar oxygen tension ratio (a/APO2), the arterial oxygen tension-inspired oxygen concentration ratio (PaO2/FIO2), the respiratory index (RI), [A-a)DO2/PaO2) and the alveolar-arterial oxygen tension difference [A-a)Do2). These indices are in use clinically despite the fact that they may not accurately predict gas exchange in situations where FIO2, Qs/QT or arterial-venous oxygen content is changing. The clinical stability of each of these indices, relative to the behaviour of the physiological shunt, was therefore investigated prospectively in ten mechanically ventilated postoperative adults as FIO2 was varied from 0.30 to 1.00. None of the indices studied reliably reflected the behaviour of the physiological shunt. As FIO2 was increased incrementally from 0.30 to 1.00, 42 to 55 per cent of the measured changes in these indices were opposite in direction to the corresponding changes in the physiological shunt. The maximum magnitudes of the opposite changes were substantial; 24 and 22 per cent for the a/APO2 and PaO2/FIO2 ratio respectively, 67 per cent for the RI and 101 per cent for the (A-a)DO2. We conclude that the use of any of these indices for clinical assessment of a patient's gas exchange defect when FIO2 is varying can be substantially misleading.     

Effect of regular training on the anthropometric parameters and urine steroids in childhood

The changes in the anthropometric data and urine steroid metabolites caused by regular training in children in two age groups (11 and 14 years old) were investigated. The skinfolds of older girls participating in regular athletic, swimming or soccer training were thinner compared with age-matched control groups (P < 0.01) and their body mass and constitution were lower (P < 0.05). In the other groups no significant differences were observable in the anthropometric parameters. The trained children in all groups had significantly higher exercise times on the cycle ergometer (P < 0.01, in young boysP < 0.05). The strength of their hands was lower in three trained groups: in younger boys (P < 0.05), in younger girls (P < 0.01) and in older girls (right handP < 0.01, left handP < 0.05). The urinary excretion of androsterone (P < 0.02), 11-ketopregnanetriol (P < 0.01) and pregnenetriol (P < 0.02) was decreased in the older trained girls; pregnenetriol was increased in younger boys (P < 0.05). Urinary excretion of cortisol metabolites was increased in trained boys [in younger boys: tetrahydrocorticosterone (P < 0.05) and 20-hydroxycortisol (P < 0.05); in older boys allotetrahydrocortisol (P < 0.02), cortisol (P < 0.05) and 20-hydroxycortisol (P < 0.05)]. There were no significant differences in the younger girls. In the trained older girls urinary excretion of cortisol metabolites was decreased: tetrahydrocortisone (P < 0.02), allotetrahydrocorticosterone (P < 0.01), tetrahydrocortisol (P < 0.05), -cortolone (P < 0.01), cortisol (P < 0.02), 6-hydroxycortisol (P < 0.01) and 20-hydroxycortisol (P < 0.05). A multivariate analysis of the data from the trained groups and sedentary, age-matched control groups showed that regular training has a significant effect on steroid excretion.