栀子水提取物对实验性2型糖尿病大鼠血糖及同型半胱氨酸水平的影响

观察栀子提取物对实验性2型糖尿病大鼠血糖、血脂及同型半胱氨酸水平的影响.采用Wistar雄性大鼠70只,随机抽取10只作为正常对照组,喂以普通维持饲料,其余60只高糖高脂饲料喂养4周后,ip链脲佐菌素(STZ)30 mg/kg建立2型糖尿病模型,7d后选取成模大鼠50只随机分为模型对照组(生理盐水)、盐酸二甲双胍对照组、栀子提取物低、中、高剂量组(0.2、0.4、0.6 g/kg),每组10只.连续ig给药4周后,观察各组大鼠血糖、血脂及同型半胱氨酸水平等变化.栀子提取物ig能降低糖尿病大鼠的血糖、甘油三酯(TG)、胆固醇(TC)、低密度脂蛋白(LDLC),同时能升高高密度脂蛋白(HDLC),降低同型半胱氨酸水平.     

Functional analysis of the Alternaria brassicicola non-ribosomal peptide synthetase gene AbNPS2 reveals a role in conidial cell wall construction

Alternaria brassicicola is a necrotrophic pathogen causing black spot disease on virtually all cultivated Brassica crops worldwide. In many plant pathosystems fungal secondary metabolites derived from non-ribosomal peptide synthetases (NPSs) are phytotoxic virulence factors or are antibiotics thought to be important for niche competition with other micro-organisms. However, many of the functions of NPS genes and their products are largely unknown. In this study, we investigated the function of one of the A. brassicicola NPS genes, AbNPS2 . The predicted amino acid sequence of AbNPS2 showed high sequence similarity with A. brassicae , AbrePsy1, Cochliobolus heterostrophus , NPS4 and a Stagonospora nodorum NPS. The AbNPS2 open reading frame was predicted to be 22 kb in length and encodes a large protein (7195 amino acids) showing typical NPS modular organization. Gene expression analysis of AbNPS2 in wild-type fungus indicated that it is expressed almost exclusively in conidia and conidiophores, broadly in the reproductive developmental phase. AbNPS2 gene disruption mutants showed abnormal spore cell wall morphology and a decreased hydrophobicity phenotype. Conidia of abnps2 mutants displayed an aberrantly inflated cell wall and an increase in lipid bodies compared with wild-type. Further phenotypic analyses of abnps2 mutants showed decreased spore germination rates both in vitro and in vivo , and a marked reduction in sporulation in vivo compared with wild-type fungus. Moreover, virulence tests on Brassicas with abnps2 mutants revealed a significant reduction in lesion size compared with wild-type but only when aged spores were used in experiments. Collectively, these results indicate that AbNPS2 plays an important role in development and virulence.     

MIND-SETS OF THE WINE CONSUMER

This paper presents the results from a study of consumer reactions to different attributes of red and white wine, with stimuli presented in the form of small, experimentally designed, test concepts (conjoint measurement). The results show that possibly four consumer mind-sets exist, with each mind-set comprising a different set of communication drivers for concept acceptance. Most subjects fit into one of three key categories; "Classics" (who want their wines to be traditional), "Imaginers" (who want to get into the drinking experience through knowing details about their wines) or "Elaborates" (who want their wines to produce many sensations and flavors). A fourth group (No Frills), were interested in simple and safe wines without any detail of flavor or origin. This segment was found in the red wine study, but not in the white wine study.     

枯草芽孢杆菌C-D6对辣椒炭疽菌附着胞形成的抑制作用研究

【目的】研究枯草芽孢杆菌(Bacillus subtilis) C-D6菌株对辣椒炭疽菌(Colletotrichum capsici)附着胞形成的抑制作用,探索炭疽病生物防治的新途径。【方法】通过对峙培养测定C-D6菌株的抗菌活性,应用摇瓶培养结合生物测定筛选产生抗菌活性成分的最适培养基,采用硫酸铵分级沉淀、Sephadex G-75凝胶柱层析和阴离子交换层析对抗菌蛋白进行分离纯化,应用聚丙烯酰胺凝胶电泳测定蛋白分子量。【结果】C-D6菌株在PDA平板上对辣椒炭疽菌显示明显的抑制作用,其YPD培养液能完全抑制该菌的附着胞形成。摇瓶培养的结果显示C-D6菌株产生抗菌活性物质的最适培养基为YPD培养基。C-D6菌株在该培养基中培养14 h后,所形成的活性物质可完全抑制辣椒炭疽菌的附着胞形成。从该菌的YPD培养液中分离获得一个分子量为32 kD,能明显抑制辣椒炭疽菌附着胞形成的抗菌蛋白。【结论】C-D6菌株的生防特征显示该菌株对防治辣椒炭疽菌引起的炭疽病具有潜在的应用价值。     

Assessing the taxonomic status of tropical frogs through bioacoustics: geographical variation in the advertisement calls in the Eleutherodactylus discoidalis species group (Anura)

The taxonomic status of a very poorly known group of Andean frogs (the Eleutherodactylus discoidalis group) is assessed through acoustic and statistical analyses of differences in temporal parameters of advertisement calls, such as the number of pulses and the call duration, and also in a spectral parameter, dominant frequency. As these species are usually misidentified or ignored because of their taxonomic complexity in both ecological and biodiversity studies, we provide a bioacoustical diagnosis for each species in order to facilitate identification in the field. Differences in acoustic parameters support the specific status of Eleutherodactylus cruralis , E. discoidalis , Eleutherodactylus ibischi , and Eleutherodactylus madidi . The name E. cruralis is probably applied to three different species: the nominal form from Amazonian forests of the Andean slopes and adjacent lowlands, and two cryptic species restricted to inter-Andean dry valleys and cloud forests from central Bolivia. Moreover, the distribution of energy through the call and the aggregation of pulses seem to be useful meristic characters for detecting interspecific differences. Populations from each macrohabitat can be recognized by distinctive advertisement calls, usually corresponding to a recognized species. For the whole group, pulse rate is significantly correlated to latitude, which could indicate a speciation process along the Andes in relation to habitat changes and isolation. © 2008 The Linnean Society of London, Zoological Journal of the Linnean Society , 2008, 152 , 353–365.     

Numerical taxonomy of Bacillus isolated from orally administered drugs

Numerical taxonomy procedures were used to study 118 strains of Bacillus isolated from non-sterile drugs prepared for oral administration. Similarities between pairs of strains were calculated by the simple matching coefficient of Sokal and Michener (S_SM). Each strain was tested for 60 unit characters and three clusters were defined. The strains in each cluster presented a similarity level of at least 60%. Cluster A comprised the strains identified as Bacillus cereus (S_SM= 93·13%), cluster B contained three subgroups corresponding to the species B. pumilus, B. subtilis and B. licheniformis (S_SM= 84·35%) and cluster C also included three subgroups that belonged to the species B. firmus, B. lentus and B. badius (S_SM= 80·14%). The most discriminating tests were selected to differentiate the clusters from the subgroups. The feature with the highest discriminating power between clusters A and B was the lack of acid production from arabinose and mannitol. The Voges-Proskauer, methyl red tests and sensitivity to polymyxin B clearly distinguished cluster A from C. The Voges-Proskauer test and acid production from arabinose were the best to differentiate between B and C. Bacillus pumilus and B. subtilis differed in starch hydrolysis and B. licheniformis in growing anaerobically. To discriminate B. firmus from B. lentus the most important tests were the acid production from glucose and sucrose; intermediate strains were found. Bacillus badius was differentiated from B. firmus by 10 tests, and from B. lentus by the production of urease.     

Peroxisomal NADP-Dependent Isocitrate Dehydrogenase. Characterization and Activity Regulation during Natural Senescence

The peroxisomal localization and characterization of NADP-dependent isocitrate dehydrogenase (perICDH) in young and senescent pea (Pisum sativum) leaves was studied by subcellular fractionation, kinetic analysis, immunoblotting, and immunoelectron microscopy. The subunit molecular mass for perICDH determined by immunoblotting was 46 kD. By isoelectric focusing (IEF) of the peroxisomal matrix fraction, the NADP-ICDH activity was resolved into four isoforms, perICDH-1 to perICDH-4, with isoelectric points (pIs) of 6.0, 5.6, 5.4, and 5.2, respectively. The kinetic properties of the NADP-ICDH in peroxisomes from young and senescent pea leaves were analyzed. The maximum initial velocity was the same in peroxisomes from young and senescent leaves, while the Michaelis constant value in senescent leaf peroxisomes was 11-fold lower than in young leaf peroxisomes. The protein levels of NADP-ICDH in peroxisomes were not altered during senescence. The kinetic behavior of this enzyme suggests a possible fine control of enzymatic activity by modulation of its Michaelis constant during the natural senescence of pea leaves. After embedding, electron microscopy immunogold labeling of NADP-ICDH confirmed that this enzyme was localized in the peroxisomal matrix. Peroxisomal NADP-ICDH represents an alternative dehydrogenase in these cell organelles and may be the main system for the reduction of NADP to NADPH for its re-utilization in the peroxisomal metabolism.     

Lifestyle modifications to prevent and control hypertension. 1. Methods and an overview of the Canadian recommendations. Canadian Hypertension Society,Canadian Coalition for High Blood Pressure Prevention and Control,Laboratory Centre for Disease Control at Health Canada,Heart and Stroke Foundation of Canada

OBJECTIVE: To provide updated, evidence-based recommendations for health care professionals on lifestyle changes to prevent and control hypertension in otherwise healthy adults (except pregnant women). OPTIONS: For people at risk for hypertension, there are a number of lifestyle options that may avert the condition--maintaining a healthy body weight, moderating consumption of alcohol, exercising, reducing sodium intake, altering intake of calcium, magnesium and potassium, and reducing stress. Following these options will maintain or reduce the risk of hypertension. For people who already have hypertension, the options for controlling the condition are lifestyle modification, antihypertensive medications or a combination of these options; with no treatment, these people remain at risk for the complications of hypertension. OUTCOMES: The health outcomes considered were changes in blood pressure and in morbidity and mortality rates. Because of insufficient evidence, no economic outcomes were considered. EVIDENCE: A MEDLINE search was conducted for the period January 1996 to September 1996 for each of the interventions studied. Reference lists were scanned, experts were polled, and the personal files of the authors were used to identify other studies. All relevant articles were reviewed, classified according to study design and graded according to level of evidence. VALUES: A high value was placed on the avoidance of cardiovascular morbidity and premature death caused by untreated hypertension. BENEFITS, HARMS AND COSTS: Lifestyle modification by means of weight loss (or maintenance of healthy body weight), regular exercise and low alcohol consumption will reduce the blood pressure of appropriately selected normotensive and hypertensive people. Sodium restriction and stress management will reduce the blood pressure of appropriately selected hypertensive patients. The side effects of these therapies are few, and the indirect benefits are well known. There are certainly costs associated with lifestyle modification, but they were not measured in the studies reviewed. Supplementing the diet with potassium, calcium and magnesium has not been associated with a clinically important reduction in blood pressure in people consuming a healthy diet. RECOMMENDATIONS: (1) It is recommended that health care professionals determine the body mass index (weight in kilograms/[height in metres]2) and alcohol consumption of all adult patients and assess sodium consumption and stress levels in all hypertensive patients. (2) To reduce blood pressure in the population at large, it is recommended that Canadians attain and maintain a healthy body mass index. For those who choose to drink alcohol intake should be limited to 2 or fewer standard drinks per day (maximum of 14/week for men and 9/week for women). Adults should exercise regularly. (3) To reduce blood pressure in hypertensive patients, individualized therapy is recommended. This therapy should emphasize weight loss for overweight patients, abstinence from or moderation in alcohol intake, regular exercise, restriction of sodium intake and, in appropriate circumstances, individualized cognitive behaviour modification to reduce the negative effects of stress. VALIDATION: The recommendations were reviewed by all of the sponsoring organizations and by participants in a satellite symposium of the fourth international Conference on Preventive Cardiology. They are similar to those of the World Hypertension League and the Joint National committee, with the exception of the recommendations on stress management, which are based on new information. They have not been clinically tested. SPONSORS: The Canadian Hypertension Society, the Canadian Coalition for High Blood Pressure Prevention and Control, the Laboratory Centre for Disease Control at health Canada, and the Heart and Stroke Foundation of Canada.