Two distinct forms of β-glucosidase, A and B, were found to occur in the cells of Pseudomonas fluorescens var. cellulosa : A was membrane-bound, while B cytosolic. They differed also from each other in some properties, such as molecular size, kinetic parameters, and susceptibility to various compounds. β-Glucosidase B was partially purified and studied especially of its substrate specificity. The results indicated that it may be an atypical β-glucosidase which possesses a certain character of exo-cellulase. 相似文献
Addition of γ-aminobutyric acid (GABA) and angiotensin converting enzyme (ACE)-inhibitory peptides to the pickles was studied in order to develop a new type of pickles that reduce blood pressure. Based on the outcome of these studies, a new type of fermentation bed composed of rice bran and white miso has been successfully developed. The advantage of such pickles is that they not only contain both GABA and ACE-inhibitory peptides, but also that their taste and flavor are excellent, with colors close to the original ones. The new type of pickles could temporarily reduce blood pressure in two types of rats, spontaneously hypertensive rats and NaCl-sensitive model rats. Thus, the newly developed pickles appear to be beneficial for pickle business. 相似文献
Abstract Previous research in our laboratory has documented seasonal alterations in humoral and cell‐mediated immunity in cotton rat (Sigmodon hispidus) populations. Based on these observations, we hypothesized that these seasonal differences in immune function were attributable in part to qualitative and quantitative numerical changes in specific splenocyte subpopulations. Lymphocytes were harvested from spleens of 139 cotton rats collected from a tallgrass prairie in central Oklahoma from December 1991 to September 1992. Unique splenocyte subpopulations were identified using fluorescein conjugated cell surface markers (concanavalin‐A, peanut agglutinin, soybean agglutinin, Helix pomatia agglutinin, pokeweed mitogen, and rabbit‐anti‐rat immunoglobulin‐G). All subpopulations examined were more abundant in fall and winter than spring and summer. Several plausible explanations for seasonal variation in abundance of splenocyte subpopulations are discussed. 相似文献
Abstract The main objective of this study was to evaluate the influence of diets enriched in individual conjugated linoleic acid (CLA) isomers, their mixture, and/or selenized yeast (Se-yeast) on the concentration of CLA isomers, long-chain polyunsaturated fatty acids (PUFA) and Se in the heart, muscles and liver of rats. The investigation was performed on 73 female Wistar rats (8 weeks of age, 200 g initial BW). After one week sub-maintenance feeding, rats received diets supplemented with 1% individual CLA isomers or 1 or 2% of a CLA isomers mixture, without or with 1.2 mg Se/kg (as Se-yeast) for 29 days. Feeding diets with 2% CLA isomer mixture reduced feed intake and body weight gain of rats, while addition of trans10,cis12 CLA and Se-yeast resulted in the highest body weight gain. CLA supplementation generally elevated the concentration of CLA isomers in heart and muscles significantly, although cis9,trans11 CLA accumulated preferentially. Regardless of the presence of Se-yeast, the dietary enrichment with CLA isomers caused a reduction in the capacity of Δ9-desaturase. Addition of Se-yeast to diets with individual CLA isomers or a 1% mixture of CLA isomers elevated the accumulation of CLA isomers in the heart and muscles, whereas all treatments with supplemented CLA and Se-yeast increased the accumulation of Se in rats compared with animals fed the diet containing Se only. Furthermore, CLA isomer supplementation decreased the concentration of PUFA and total fatty acids in the heart and muscles compared with control rats. Moreover, addition of CLA isomers interfered in the conversion of linoleic and linolenic acids to higher metabolites due to competition of CLA isomers for the same enzymes (Δ6-, Δ5-, Δ4-desaturases and elongase). 相似文献
A wearable scanning photoacoustic imaging (wPAI) system is presented for noninvasive brain study in behaving rats. This miniaturized wPAI system consists of four pico linear servos and a single transducer‐based PAI probe. It has a dimension of 50 mm × 35 mm × 40 mm, and a weight of 26 g excluding cablings. Phantom evaluation shows that wPAI achieves a lateral resolution of ~0.5 mm and an axial resolution of ~0.1 mm at a depth of up to 11 mm. Its imaging ability is also tested in a behaving rat, and the results indicate that wPAI is able to image blood vessels at a depth of up to 5 mm with intact scalp and skull. With its noninvasive, deep penetration, and functional imaging ability in behaving animals, wPAI can be used for behavior, cognition, and preclinical brain disease studies.
目的:研究分析两种不同电针方法对慢性应激抑郁模型大鼠(CUMS)下丘脑中促甲状腺激素释放激素(TRH)表达的影响。方法:选取60只健康雄性SPF级SD大鼠编号后采用随机数字表法分为对照组(正常喂养)、模型组(仅建立CUMS模型,不予治疗)、观察组A(建立CUMS模型后,脉冲电针治疗)、观察组B(建立CUMS模型后,音乐电针治疗)、氟西汀组(建立CUMS模型后,氟西汀治疗)各12只,对除对照组之外的其他各组大鼠进行1只/笼的孤养结合方式建造CUMS模型,利用开野实验观察各组大鼠行为学改变,采用实时荧光定量(PCR)法测定各组大鼠下丘脑组织中TRH m RNA的表达,采用免疫组化法测定TRH蛋白的表达。结果:在刺激21 d后,模型组大鼠的水平运动次数、垂直运动次数显著的低于对照组、实验组A、实验组B、氟西汀组,且差异均具有统计学意义(P0.05),实验组A、实验组B、氟西汀组大鼠的水平运动次数、垂直运动次数显著低于对照组,且差异均具有统计学意义(P0.05),实验组A、实验组B、氟西汀组大鼠的水平运动次数、垂直运动次数差异无统计学意义(P0.05);模型组大鼠的下丘脑TRH m RNA、TRH蛋白水平低于对照组、实验组A、实验组B、氟西汀组,且差异均具有统计学意义(P0.05),实验组A、实验组B、氟西汀组大鼠的大鼠的下丘脑TRH m RNA、TRH蛋白水平显著低于对照组,且差异均具有统计学意义(P0.05);实验组A、实验组B、氟西汀组大鼠的大鼠的下丘脑TRH m RNA、TRH蛋白水平差异无统计学意义(P0.05)。结论:CUMS大鼠下丘脑中促甲状腺激素释放激素表达水平降低,脉冲电针与音乐电针能有效逆转这一现象,效果相当。 相似文献