海风藤及其代用品药理作用的比较研究

选择经典的实验指标，对海风藤及其３种代用品山Ｊｕ，石楠藤有毛Ｊｕ的药理作用进行了比较研究，结果表明海风藤，山Ｊｕ和毛Ｊｕ在抗炎，镇痛和抗血小板聚集方面均有效，其中海风藤作用最强，其次为山Ｊｕ，毛Ｊｕ石楠藤没有明显的抗炎作用，其抗血小板聚集及止痛作用稍强于毛Ｊｕ。     

海风藤化学成分及神经保护活性研究

目的 对海风藤Piperis kadsurae藤茎的化学成分进行研究,并对分离的化合物进行初步的神经保护活性筛选。方法 运用硅胶、ODS、和Sephadex LH-20等柱色谱以及反相制备型HPLC等各种现代色谱分离技术进行系统的分离纯化,利用波谱学方法确定化合物结构。同时采用MTT和RTCA法,以白藜芦醇作为阳性对照,对化合物进行体外神经保护活性实验。结果 从海风藤藤茎的二氯甲烷和醋酸乙酯提取物中分离得到22个化合物,分别鉴定为puberulin(1)、(-)-acuminatin(2)、dihydrocarinatin(3)、海风藤酮（4）、山蒟素C(5)、3-羟基苯甲酸苄酯（6）、2-羟基苯甲酸苄酯（7）、cherrevenol D(8)、trans-2,3-diacetoxy-1-[(benzoy1oxy)methyl]-cyclohexa-4,6-diene (9)、(3R,4R)-4-O-acetyl-5-(benzoyloxymethyl)cyclohexa-1,5-diene-3,4-diol(10)、(-)-sootepoxidechlorohydrinA(11)、香...     

山蒟醇提取物的抗血小板聚集作用?

以山蒟醇提取物在兔的体内和体外-体内进行抗血小板聚集实验。结果表明山蒟醇提取物可抑制由血小板活化因子和花生四烯酸所致的血小板聚集,对2者所致的血小板聚集（体外试验）的IC_（50）。分别为40． 34、345． 46 mg／L。静脉注射山蒟醇提取物30 mg／kg,15 min后产生的抗血小板聚集作用最明显,其对血小板活化因子和花生四烯酸所致的血小板聚集（体内-体外试验）的抑制率分别为82．75％和33．34％;血小板聚集的持续时间分别为60、30 min。这表明山蒟醇提取物对血小板活化因子作用有一定的选择性。     

New optimized piperamide analogues with potent in vivo hypotensive properties

We describe herein the structural optimization of new piperamide analogues, designed from two natural prototypes, piperine 1 and piperdardine 2, obtained from Piper tuberculatum Jacq. (Piperaceae). Molecular modeling studies using semiempirical AM1 method were made in order to establish rational modifications to optimize them by molecular simplification. The targeted compounds (10) and (11) were respectively obtained using benzaldehyde (12) and para-anisaldehyde (13) as starting materials. ¹H NMR spectra showed that the target compounds were diastereoselectively obtained as the (E)-isomer, the same geometry of the natural prototypes. These new synthetic amides presented significant hypotensive effects in cardiovascular essays using in vivo methodologies. Compound 11 (N-[5-(4′-methoxyphenyl)-2(E)-pentenoyl]thiomorpholine) showed a potency 10,000 times greater than its prototype 5, evidencing an optimization of the molecular architecture for this class of hypotensive drug candidates.     

Integrated plant nutrient system – with special emphasis on mineral nutriton and biofertilizers for Black pepper and cardamom – A review

Abstract

Integrated Plant Nutrition System (IPNS) as a concept and farm management strategy embraces and transcends from single season crop fertilization efforts to planning and management of plant nutrients in crop rotations and farming systems on a long-term basis for enhanced productivity, profitability and sustainability. It is estimated that about two-thirds of the required increase in crop production in developing countries will have to come from yield increases from lands already under cultivation. IPNS enhances soil productivity through a balanced use of soil nutrients, chemical fertilizers, combined with organic sources of plant nutrients, including bio-inoculants and nutrient transfer through agro-forestry systems and has adaptation to farming systems in both irrigated and rainfed agriculture. Horticultural crops, mainly plantation crops, management practices include application of fertilizers and pesticides which become inevitable due to the depletion of soil organic matter and incidence of pests and diseases. The extensive use of chemical fertilizers in these crops deteriorated soil health that in turn affected the productivity. To revitalize soil health and to enhance productivity, it is inexorable to enrich the soil using microorganisms. The lacunae observed here is the lack of exploitation of indigenous microbes having the potential to fix atmospheric nitrogen (N) and to solubilize Phosphorus (P) and Potassium (K). The concept of biofertilizer application appears to be technically simple and financially feasible, but the task of developing biofertilizers with efficient strains in appropriate combinations in a consortia mode is not easier. More than developing consortia, a suitable delivery system to discharge the microbial inoculants warranted much effort. This review focuses on the integrated plant nutrition system incorporating biofertilizer with special emphasis on developing and formulating biofertilizer consortium.     

Effect of Extract of Leaf and Seed of Piper guineense on Some Smooth Muscle Activity in Rat,Guinea-pig and Rabbit

Extracts of the leaf and seed of Piper guineense were separately prepared and their pharmacological effects screened using smooth muscle of the gastrointestinal tract and uterus. The leaf extract enhanced both the frequency and tone of spontaneous contractions of rabbit jejunum and induced contraction of guinea-pig ileum, which were blocked by atropine. The seed extract had the opposite effect on rabbit jejunum, an inhibition which was antagonized by prazocin, and little or no effect on guinea-pig ileum. Both extracts had a stimulant effect on rat uterine muscle, the seed extract to a lesser extent.     

Effect of muscle length on surface EMG wave forms in isometric contractions

Summary To elucidate the influence of muscle length on surface EMG wave form, comparisons were made of surface EMGs of the biceps and triceps brachii muscles during isometric contractions at different muscle lengths. Muscle lengths were altered by setting the elbow joint angle at several intervals between the limits of extension and flexion. The intensity of the isometric contractions was 25% of maximum voluntary contraction at the individual joint angles. Slowing was obvious in the EMG wave forms of biceps as muscle length increased. The so-called Piper rhythm appeared when the muscle was more than moderately lengthened. The slowing trend with muscle lengthening, though less marked, was also seen in triceps. Zero-cross analysis revealed quasi-linear relationships between muscle length and slowing. Frequency analysis confirmed the development of Piper rhythm. An attempt was made to interpret the slowing associated with muscle lengthening in terms of the propagation of myoelectric signals in muscle fibers. Given the effect of muscle length on EMG wave forms, a careful control of joint angle may be required in assessing local muscle fatigue when using EMG spectral indices.     

Safety review of kava (Piper methysticum) by the Natural Standard Research Collaboration

This systematic review discusses the proposed uses, dosing parameters, adverse effects, toxicology, interactions and mechanism of action of kava. The widespread concern regarding the potential hepatotoxicity of kava is discussed. A recommendation is made to consolidate and analyse available reports and to continue postmarket surveillance in an international repository to prevent duplicates and promote collection of thorough details at the time of each report so that any association with kava is clearly defined.     

High dose of commercial products of kava (Piper methysticum) markedly enhanced hepatic cytochrome P450 1A1 mRNA expression with liver enlargement in rats

Commercial products containing the kava plant (Piper methysticum), known to have the anxiolytic activity, are banned in several European countries and Canada because of the suspicion of a potential liver toxicity. In some reports, kava and kavalactones (major constituents of kava) inhibited activities of cytochrome P450 (CYP) isoforms including CYP1A2. On the other hand, a few studies showed that administration of kava to rats moderately increased CYP1A2 proteins in the liver. CYP1A isoforms are likely responsible for the metabolic activation of potent carcinogenic environmental toxins such as aflatoxins, benzo[a]pyrene, and others. On these bases, we have investigated the effects of administration of commercial kava products on gene expression of hepatic CYP1A isoforms in rats. A high dose (equivalent to approximately 380 mg kavalactones/kg/day; 100 times of the suggested dosage for human use) of two different types of kava products for 8 days significantly increased liver weights. CYP1A2 mRNA expression was moderately increased (2.8–7.3 fold). More importantly, the high dose of kava markedly enhanced CYP1A1 mRNA expression (75–220 fold) as well as ethoxyresorufin O-deethylase activities and CYP1A1 immunoreactivities. Thus, no observed adverse effect levels of kavalactones would be lower than 380 mg/kg/day. When the safety factor of kavalactones is assumed to be 100, a value most often used upon the risk analysis of chemicals and designed to account for interspecies and intraspecies variations, a number of kava product users likely ingest more kavalactones than acceptable daily intakes. Based on overall evidence, we should pay considerable attention to the possibility that kava products induce hepatic CYP1A1 expression in human especially in sensitive individuals.     

荜茇挥发油清除自由基作用及其与分子结构的关系

目的观察海南产荜茇挥发油清除自由基活性,探讨其与分子结构的关系。方法DPPH法检测清除自由基活性;GC-MS法分析其化学成分,并用谱库检索确定各化合物结构。结果①荜茇挥发油具有清除DPPH自由基的能力,且浓度越高,活性越强;②海南产荜茇挥发油含41个化合物,碳碳双键C=C的相对含量占绝对优势。结论碳碳双键C=C可能为荜茇挥发油清除自由基活性的必需官能团。