当归抽薹植株生理生化特征分析

目的 研究在蛋白质及酶水平上的当归抽薹发育机制,为进一步阐明当归抽薹过程所发生的生理生化指标变化及预防当归抽薹提供理论依据。方法 观察当归抽薹与未抽薹植株的糖代谢及过氧化物酶（POD）、多酚氧化酶（PPO）等活性的变化,测定抽薹与未抽薹当归植株游离氨基酸、可溶性糖和可溶性蛋白的量。结果 在抽薹前10 d,未抽薹植株的游离氨基酸量和POD活性、PPO活性分别比抽薹植株高1.3 mg/g和0.02 U/(min·g)、0.014 U/(min·g),抽薹植株的可溶性糖和可溶性蛋白量分别比未抽薹植株高2.2%、0.5%。在抽薹期,未抽薹植株的可溶性糖和可溶性蛋白量较高,而抽薹植株的游离氨基酸量和PPO和POD活性较高。结论 当归抽薹过程多个生化指标发生变化,当归栽培中应防止早期抽薹的发生。     

姜黄属药用植物的3种同工酶分析

目的 探讨姜黄属Curcuma L. 6种郁金类药用植物的种间及其种内不同居群间的亲缘关系。方法 采用聚丙烯酰胺凝胶电泳（PAGE）,分析超氧化物歧化酶（SOD）、多酚氧化酶（PPO）、细胞色素氧化酶（COD）的酶带,并采用UPGMA法对数据进行分析。结果 SOD、PPO和COD的酶谱能较好地区分6种郁金类药用植物;PPO和COD还能够对种内不同居群的材料进行区分。结论 同种植物不同居群间亲缘关系的远近与地理来源有关;能够通过聚类分析区分姜黄和川郁金;姜黄属郁金类植物的栽培型和野生型产生了分化。     

半夏干燥过程中褐变机制的研究

目的 研究导致半夏干燥过程中发生褐变的机制。方法 采用紫外分光光度法检测干燥过程中半夏中多酚氧化酶活性的变化,使用色彩色差计测量半夏表面颜色的变化值,考察酶促反应是否是发生褐变的唯一机制。采用HPLC-ELSD法检测半夏中还原性糖的种类及含量,分析半夏中的氨基酸种类,判断其发生羰氨反应的可能性。结果 导致半夏褐变的反应并不唯一,酶促反应对其颜色变化的影响主要发生在干燥前期,羰氨反应对半夏褐变也有影响。结论 导致半夏干燥过程中发生褐变的机制并不单一,酶促反应和羰氨反应都对其颜色变化有影响。     

Quantitative Perfusion Scintigraphy or Anatomic Segment Method in lung cancer resection

Background

Quantitative Perfusion Scintigraphy (QPS) and Anatomic Segment Method (ASM) are two techniques for estimating postoperative pulmonary function. QPS is gold standard, but holds disadvantages.

Aim

Could ASM substitute QPS in the preoperative work-up of NSCLC?

Methods

Retrospective study in patients with NSCLC or mesothelioma undergoing resection. FEV1 and DL,CO were estimated by QPS and ASM and compared to pulmonary function measured 3 months after resection. Correlation tests and Bland-Altman analyses were performed.

Results

40 patients (23 lobectomies, 14 pneumonectomies). Both methods correlated similarly with postoperative FEV₁ (QPSρ = 0.69; ASMρ = 0.75) and DL,CO (QPSρ = 0.70; ASMρ = 0.74). Correlation between both methods was high (ppoFEV₁ρ = 0.89; ppoDL,COρ = 0.89). The same principles applied in a subgroup analysis of patients with COPD. Bland-Altman analyses showed that ASM underestimated postoperative FEV₁ and DL,CO more than QPS in all groups.

Conclusion

QPS and ASM are remarkably similar in predicting postoperative pulmonary function. As ASM underestimates pulmonary function more, it could be a safe alternative from a cost-benefit point of view. Based on these results, it appears that QPS could be restricted to patients in whom ASM suggests functional inoperability, although further prospective studies are necessary.     

FTIR Imaging of Poly(3‐hydroxybutyrate) and Isotactic Poly(propylene oxide) Spherulites

FTIR spectroscopic imaging is combined with linear dichroism measurements to investigate the structures of spherulites of poly(3‐hydroxybutyrate) and isotactic poly(propylene oxide). It is shown that this technique can be used to easily gain qualitative information about relative orientations of chemical bonds within a solid polymeric sample. Furthermore the imaging technique is shown to have the considerable advantage that the obtained images are easy to understand and easy to interpret even without deep knowledge of FTIR linear dichroism measurements.

     

Transcatheter closure of patent foramen ovale in older adults.

OBJECTIVES: Comparing results of patent foramen ovale (PFO) closure in older and younger patient cohorts. BACKGROUND: The literature pertaining to stroke and PFO has focused on patients <55 years of age. METHODS: Between March 2000 and December 2003, 456 consecutive stroke/transient ischemic attack (TIA) patients (14.2-91.1 years, mean 51.4 +/- 15.5) underwent successful closure of PFO with a CardioSEAL Septal Occluder by one operator at five hospitals. Of the 456 patients, 184 (40.4%) were >55 years of age at the time of the procedure (mean 66.9 +/- 8.3 years) and comprise the subject group (OLDER). The remaining 272 patients (mean 41.1 +/- 7.7) comprise the control group (YOUNGER). Data were collected prospectively in a registry type format. RESULTS: Minor procedural complications were comparable: 7/184 (3.8%) OLDER vs. 12/272 (4.4%) YOUNGER (P = NS). In the follow-up period (1-45 months, mean = 17.8 +/- 11.1), there was no significant difference in the rate of recurrent stroke/TIA, headaches, or late unrelated death. Forty OLDER patients and 47 YOUNGER developed new onset atrial arrhythmia (P = NS). The incidence of new onset atrial fibrillation (AF), however, was significantly higher in OLDER (14/40 OLDER and only 2/47 YOUNGER, P < 0.025). All patients who were in normal sinus rhythm (NSR) before the procedure are in NSR at last follow-up. CONCLUSIONS: Older patients should not be excluded from PFO closure. The procedure seems as safe and effective in preventing recurrent stroke in the older, as in the younger population. Older patients seem more prone to developing AF.     

Oxidative metabolism of mescaline in the central nervous system. IV. In vivo metabolism of mescaline and 2,3,4-trimethoxy-beta-phenylethylamine

Metabolic rates of mescaline (3,4,5-trimethoxy-β-phenylethylamine) and of its non-hallucinogenic isomer, 2,3,4-trimethoxy-β-phenylethylamine were studied in whole and in different areas of mouse brain in vivo. The effects of Pargyline and of Probenecid on the concentrations of the amines and their corresponding metabolites, together with the results obtained from intraventricular injections of mescaline suggested the formation of the trimethoxyphenylacetic acids in the brain.The metabolic differences between mescaline and 2,3,4-trimethoxy-β-phenylethylamine are discussed in terms of possible implications of metabolic parameters with psychotomimetic activity.     

Oxidative metabolism of mescaline in the central nervous system. 3. Side chain degradation of mescaline and formation of 3,4,5-trimethoxy-benzoic acid in vivo

After intraperitoneal injection of 8-[¹⁴C]mescaline. HCl into mice 0.05 per cent of the injected radioactivity was found within 1 hr in the respiratory gases. This observation prompted us to search for mescaline metabolites with a degraded side chain. 3,4,5-trimethoxy-benzoic acid was identified in brain and liver by derivative formation and mass spectrometry. N-acetyl-mescaline was also identified by mass spectrometry. Some new cationic mescaline metabolites were detected in brain but the available data did not allow us to establish conclusively the structure of these compounds     

Mechanisms of diethyldithiocarbamate-induced loss of cytochrome P-450 from rat liver

A single, intraperitoneal injection of diethyldithiocarbamate (DDTC) to adult, male Sprague-Dawley rats decreased hepatic cytochrome P-450 (P-450) concentrations. This effect was dose-dependent over a range of 250 to 750 mg/kg and most prominent 24-36 hr after dosing. Depletion of hepatic glutathione (GSH) by diethylmaleate (DEM) administration significantly decreased P-450 8 hr after concurrent treatment with DDTC at a dose which given alone had little effect on P-450 concentrations. When hepatic microsomes were incubated with DDTC in the presence of NADPH, P-450 was converted to cytochrome P-420 (P-420). Similar incubations employing [35S]DDTC demonstrated strict NADPH-dependent binding of labeled sulfur to microsomal membranes, suggesting that diminished P-450 concentrations are related to the metabolic activation of DDTC. Addition of reduced GSH to incubation mixtures blocked the binding of 35S to microsomal membranes, as well as conversion of P-450 to P-420. DDTC inhibited NADPH-ADP3+ mediated peroxidation of microsomal lipids in vitro, suggesting that the effect of DDTC on P-450 does not result from stimulation of lipid peroxidation, but may be influenced by the levels of hepatic GSH. DDTC treatment 1 hr after P-450 was pulse labeled by an intravenous injection of [3H]delta-aminolevulinic acid resulted in a 2-fold increase in the rate of loss of radioactivity associated with membrane-bound P-450 heme during the next 20 hr. Within this time interval, hepatic heme oxygenase (HO) activity increased and at 8 hr after dosing was 7-fold greater than control values in the livers, but was unchanged in the kidneys and spleens of DDTC-treated animals. An elevation of hepatic delta-aminolevulinic acid synthetase (delta-ALAS) activity occurred at 8 and 24 hr after DDTC treatment. Since this enzyme is rate limiting in the biosynthesis of heme, its increased activity may represent a compensatory response to offset the DDTC-mediated loss of P-450 heme.     

Absorption, distribution and metabolism of propyl anthranilate.

Analysis of the gut contents of rats killed at intervals after dosage with propyl anthranilate or anthranilic acid suggested that both acid and ester were absorbed rapidly; the chief site of absorption was the stomach. Not more than a trace of the ester was hydrolysed in the stomach but of the dosed ester detected in the small intestine (less than 7%) a considerable proportion, increasing with time after dosing was present as anthranilic acid. Measurement of the level of radioactivity in the blood after administration of 14C-labelled propan-1-ol, propyl anthranilate or anthranilic acid showed that the alcohol was absorbed more rapidly than either the ester or acid. Unchanged propyl anthranilate was readily detected in the blood of rats dosed with the ester and some unhydrolysed ester was excreted in the urine. The level of radioactivity of the organs of rats 2 h and 4 h after administration of the 14C-labelled compounds was measured. Velocity constants for the excretion of 14CO2 by rats dosed with 14C-labelled propyl anthranilate were significantly lower than those found for rats dosed with [14C]propan-1-ol indicating a limiting step in the metabolism of the propyl moiety of the ester which did not occur in the metabolism of propan-1-ol. The urinary metabolites of anthranilic acid excreted by rabbits and rats dosed with the acid were qualitatively the same as those excreted by these species after dosing with propyl anthanilate; some quantitative differences were however, observed.