Advanced glycation end products and sorbitol in blood from differently compensated diabetic dogs

Canine diabetes mellitus (DM) is a common metabolic disorder with long term complications, most of which are caused by glycosylation of structural proteins, decreases in antioxidant concentrations, altered osmotic balance and hypoxia due to impaired oxygen transport. Previous studies have demonstrated that under hyperglycemic conditions canine erythrocytes undergo swelling, probably due to activation of the polyol pathway. The present work aimed to assess the plasma concentration of advanced glycation end (AGE) products, stable Amadori-products generated by non-enzymatic glycosylation of proteins and the intracellular concentration of sorbitol, produced by the activation of polyol pathway in 34 blood samples from diabetic dogs and in 14 controls. AGE products were significantly higher (p<0.01) in plasma from diabetic dogs compared with control animals. The sorbitol concentration in erythrocytes was also significantly higher in diabetic dogs and, in particular, in poorly compensated animals and in dogs with ketonuria. In five cases that were analysed before and after clinical improvement, sorbitol concentration was found to correlate with improvement. These results suggest that non-specific glycosylation is increased and that the polyol pathway is activated in diabetic dogs in a manner that is proportionate to the severity of disease. Moreover, the concentration of AGE products and sorbitol may be useful for monitoring the onset of diabetic complications and assessing the most appropriate therapeutic approaches for management of canine DM.     

枝龄、顶芽、IBA对无花果硬枝扦插成苗的影响

枝龄、顶芽、 ＩＢＡ分别对无花果硬枝扦插成苗有极显著的影响。三因素不同水 平的成苗效应分别为：１年生枝极显著大干２－３年生枝，有顶芽极显著大于无顶 芽，１０００ｐｐｍＩＢＡ处理插条１小时极显著大于清水处理。成苗最优组合为有顶芽 的１年生枝用ＩＢＡ处理（８６、７％）。无顶芽的２－３年生枝用ＩＢＡ处理亦有较好的成苗 率（７０．０％）。无花果为皮部生根类型，、不定根的发生、生长基本上与萌芽、展 叶同时进行。     

马尾松天然林采伐年龄的研究

本文对四川蒲江县马尾松天然林采伐年龄进行了研究。试验选定Richard生长模型为马尾松天然林的基本模型，建立了胸径、树高、材积与年龄的生长模型，编制出马尾松生长过程表与林分出材率表，用现行木材价格计算木材收入，采用指率法进行经济分析确定出经济成熟龄。经与实行多年的马尾松天然林采伐年龄相比，其采伐年龄推迟10年左右。     

茜草色素潜在毒性研究

用抑菌试验、琼脂糖凝胶电泳试验、紫外分光光度法检测茜草色素中的3种蒽醌化合物茜素、红紫素、1-羟基蒽醌对大肠杆菌的影响。结果表明,3种蒽醌化合物能够抑制大肠杆菌的生长,并且会改变大肠杆菌基因组DNA的结构,说明茜草色素虽然为天然色素,但其具有潜在毒性。     

南江黄羊非胴体组成部分影响因素的研究

本试验用２×２×２因子试验估计了营养，性别和年龄对肉用山羊品种南江黄羊非胴体组织的影响。营养、性别和年龄对总非胴体组织重量有显著影响。不同因子间交互作用对总非胴体组织重量影响不显著。大多数非胴体组织部分，如体外器官，胸内器官和腹腔器官极显著（Ｐ＜０．００１）和显著地（Ｐ＜０．０５）受到营养、性别和年龄因子的影响。最小二乘分析结果表明：在低营养水平下，南江黄羊公羊非胴体组织重量比母羊重。在高营养水平时，公母羊间非胴体组织总重量间的差异减小。年龄和性别对非胴体组织总量和影响始终显著     

Methylglyoxal-induced modifications of significant honeybee proteinous components in manuka honey: Possible therapeutic implications

Methylglyoxal (MGO) is a major antibacterial component of manuka honey. Another antibacterial component found in Revamil honey, peptide defensin1, was not identified in manuka honey. The primary aim of the study was to evaluate the content of defensin1 in honeys of different botanical origins and to investigate a presumed effect of reactive MGO on defensin1 and a dominant protein of honey MRJP1 in manuka honey. Immunoblotting of honey samples showed that defensin1 was a regular but quantitatively variable component of honeys. One of the reasons of varying contents of defensin1 in different honeys seems to be constitutive but varying defensin1 expression in individual honeybees in bee populations that we documented on samples of nurse and forager bees by RT-PCR. Comparative analyses of honeys revealed a size modification of defensin1, MRJP1 and probably also α-glucosidase in manuka honey. We further showed that (i) the treatment of purified defensin1 in solution containing high amount of MGO caused a time-dependent loss of its antibacterial activity and (ii) increasing MGO concentrations in a non-manuka honey were connected with a gradual increase in the molecular weight of MRJP1. Obtained results demonstrate that MGO abrogates the antibacterial activity of defensin1 and modifies MRJP1 in manuka honey. We assume that MGO could also have negative effects on the structure and function of other proteins/peptides in manuka honey, including glucose oxidase, generating hydrogen peroxide.     

福建秃杉管胞形态及化学成分的研究

通过对福建首次发现的速生珍稀树种秃杉木材的管胞形态及化学成分的测定和分析,揭示了秃杉管胞形态的特征及其变化规律,阐明了秃杉木材各种化学成分比例及其特点,并与杉木、马尾松的管胞形态和化学成分进行比较分析。结果表明秃杉木材可作为林产工业的纤维材料使用。为秃杉大力营造人工林提供科学依据。     

IBA、树龄、枝段对日本晚樱绿枝扦插生根的影响

①IBA树龄、枝段对日本晚樱插穗生根率和壮苗率均有极显著的影响 ,在这 3因素中 ,用IBA处理 1年生树龄枝的基段作插穗较好 ;②插穗生根率高低可反映扦插苗质量 ;③愈伤组织发生率受插穗生理成熟度影响 ,而与IBA处理与否无关