Fermentation RS3 derived from sago and rice starch with Clostridium butyricum BCC B2571 or Eubacterium rectale DSM 17629

Resistant starch type 3 (RS3) is retrograded starch which is not digested by human starch degrading enzyme, and will thus undergo bacterial degradation in the colon. The main fermentation products are the Short Chain Fatty Acid (SCFA): acetate, propionate and butyrate. SCFA has significant benefit impact on the metabolism of the host. The objectives of this research were to study the SCFA profile produced by colonic butyrate producing bacteria grown in medium containing RS3. RS3 was made from sago or rice starch treated with amylase, pullulanase and the combination of amylase and pullulanase. Fermentation study was performed by using Clostridium butyricum BCC B2571 or Eubacterium rectale DSM 17629, which has been identified as capable of degradation of starch residue and also regarded as beneficial bacteria. Experimental result revealed that enzyme hydrolysis of retrograded sago or rice starch was beneficial to RS formation. RS3 derived from sago contained higher RS (31-38%) than those derived from rice starch (21-26%). This study indicated that C. butyricum BCC B2571 produced acetate, propionate and butyrate at molar ratio of 1.8 : 1 : 1, when the medium was supplemented with RSSA at concentration 1%. In the medium containing similar substrate, E. rectale DSM 17629 produced acetate, propionate and butyrate at molar ratio of 1.7 : 1 : 1.2. High levels of acetate, propionate and butyrate at molar ratio of 1.8 : 1 : 1.1 was also produced by E. rectale DSM 17629 in medium supplemented with RSSP at concentration 1%. The results showed that both bacteria responded differently to the RS3 supplementation. Such result provided insight into the possibility of designing RS3 as prebiotic with featured regarding SCFA released in the human colon with potential health implication.     

三角帆蚌Nacrein基因克隆、蛋白提纯及其对珍珠晶体成型的影响

为研究三角帆蚌Nacrein蛋白对珍珠晶体成型的影响,通过巢式及3′-RACE PCR对三角帆蚌基质蛋白Nacrein基因3′端序列进行克隆,得到850bp碱基片段,分析表明其与合浦珠母贝同源基因序列相似度为56%,与马氏珠母贝相似度为50%。试验通过水提法初步分离出珍珠质水溶性基质蛋白,并采用快速蛋白液相色谱(fast protein liquid chromatography,FPLC)分离出分子量约为60kD的Nacrein蛋白。此外,采用配对试验设计,对试验组外套膜组织培养样品加入Nacrein蛋白,研究Nacrein蛋白对晶体成型的影响,结果显示,加入Nacrein蛋白的试验组结晶成棱形状;而未加Nacrein蛋白的对照组结晶成雪花状,而且在晶体形成的时间上,试验组也较之对照组要早。研究表明,Nacrein蛋白能加速外套膜组织分泌的钙质形成棱状结晶,从而对晶体成型产生影响。本研究为进一步研究基质蛋白对生物矿化的作用提供试验依据,对珍珠培育生产有一定指导意义。     

Parameters of photic stimulation and characteristics of thermal response in the white rat cerebral cortex

The dynamics of the localized thermal response produced in the cerebral cortex when a retinal photic stimulation pattern is established were studied through the unopened skull during acute experiments on white rats using techniques of thermovision and digital image processing. The relationship was evaluated between amplitude, time course, and spatial characteristics of response on the one hand and stimulus size, position on the retina, focus, duration, quantity, and frequency of presentation on the other. A discussion follows of the properties, significance, and underlying mechanisms of the thermal effects discovered.Institute of Higher Nervous Activity and Neurophysiology, Academy of Sciences of the USSR, Moscow. Translated from Neirofiziologiya, Vol. 18, No. 3, pp. 332–340, May–June, 1985.     

Four new cassane diterpenes from the seeds of Caesalpinia minax

In our survey on the chemical composition of traditional Chinese medicines to further elucidate their chemical substances for the treatment of diseases, we investigated the chemical constituents of the seeds of plants Caesalpinia minax. The investigation led to the isolation and identification of four new cassane diterpenes, caesalpines A–D (1–4). Their structures were elucidated on the basis of extensive 1D and 2D NMR (COSY, HMQC, HMBC, and NOESY) and mass (ESIMS and HR-ESIMS) spectroscopic data analyses. The phytochemical results imply that cassane diterpenes are maybe regarded as the characteristic constituents of C. minax.     

Atorvastatin Treatment of Rats with Ischemia-Reperfusion Injury Improves Adipose-Derived Mesenchymal Stem Cell Migration and Survival via the SDF-1α/CXCR-4 Axis

Background

Adipose-derived mesenchymal stem cells (ASCs) transplantation is a promising approach for myocardium repair. Promotion of ASCs migration and survival is the key for improving ASCs efficiency. SDF-1α is a critical factor responsible for ASCs migration and survival. Atorvastatin (Ator) is capable of up-regulating SDF-1α. Therefore, we''re going to investigate whether ASCs migration and survival could be improved with atorvastatin.

Methods

In vitro study, cardiomyocytes were subjected to anoxia-reoxygenation injury and subsequently divided into different groups: group blank control, Ator, Ator plus L-NAME (A+L-NAME) and Ator plus AMD3100 (A+AMD3100).When migration analysis completed, cardiomyocytes were used for subsequent analyses. In vivo study, rats underwent ischemia-reperfusion injury were assigned into different groups corresponding to in vitro protocols. ASCs were transplanted on the seventh day of atorvastatin therapy. Seven days later, the rates of migration, differentiation and apoptosis were evaluated.

Results

Compared with other groups, ASCs migration in vitro was significantly improved in group Ator, which was dependent on SDF-1α/CXCR-4 coupling. Results of in vivo study were consistent with that of in vitro study, further supporting the notion that the efficacy of atorvastatin on ASCs migration improvement was related to SDF-1α/CXCR-4 axis. Higher vessel density in group Ator might be another mechanism responsible for migration improvement. Concomitantly, apoptosis was significantly reduced in group Ator, whereas no significant difference of differentiation was found.

Conclusion

Migration and survival of ASCs could be improved by atorvastatin under ischemia-reperfusion injury, which were ascribed to SDF-1α/CXCR-4 axis.     

小檗碱对CT26皮下移植瘤组织中肿瘤相关巨噬细胞的影响

目的观察小檗碱的抑瘤作用及其对肿瘤组织内肿瘤相关巨噬细胞数量的影响。方法 BABL/c小鼠40只随机分2组,全部皮下移植结肠癌细胞(CT26细胞系),次日进行药物干预。治疗组小鼠腹腔注射小檗碱,100mmol/L,200μl/d,14d;对照组腹腔注射等量生理盐水。肿瘤细胞接种7d后连续动态测定肿瘤体积,接种15d处死全部动物,取肿瘤组织、免疫组织化学显色检测肿瘤组织中M2型巨噬细胞标志物CD206及CD68的表达。结果小鼠皮下移植CT26后,小檗碱治疗组小鼠皮下移植瘤生长缓慢。与对照组比较,肿瘤体积及瘤重均显著减少(P<0.05);皮下移植15d肿瘤组织中可见大量CD206及CD68阳性细胞;肿瘤组织中CD206及CD68阳性细胞数量显著减少(P<0.05 orP<0.01)。结论小檗碱可能通过抑制肿瘤相关巨噬细胞的形成而发挥抗肿瘤作用。     

Plasma C-Type Natriuretic Peptide as a Predictor for Therapeutic Response to Metoprolol in Children with Postural Tachycardia Syndrome

POTS is a global public-health disease, but predictor for therapeutic response to metoprolol in children with POTS is lacking. This study was designed to investigate predictive value of plasma C-type natriuretic peptide (CNP) in the therapeutic efficacy of metoprolol on postural tachycardia syndrome (POTS) in children. Totally 34 children with POTS and 27 healthy children were included in the study. The head-up test or head-up tilt test was used to check heart rate and blood pressure from supine to upright in subjects. A double antibody (competitive) sandwich immunoluminometric assay was used to detect plasma CNP. Metoprolol was used to treat children with POTS. The difference in plasma concentrations of CNP between responders and non-responders was compared. An ROC curve was used to analyze plasma CNP to predict efficacy of metoprolol on POTS in children. Plasma CNP in children with POTS was significantly higher than that of healthy children [(51.9 ± 31.4) vs. (25.1 ± 19.1) pg/ml, P <0.001]. Plasma CNP in responders to metoprolol was significantly higher than non-responders [(59.1 ± 33.5) vs. (34.8 ± 16.7) pg/ml, P = 0.037] before treatment. The ROC curve showed that area under the curve was 0.821 (95% CI 0.642–0.999). The cut-off value of plasma CNP > 32.55 pg/ml yielded a sensitivity of 95.8% and specificity of 70% in predicting therapeutic efficacy of metoprolol on POTS children. Plasma CNP might serve as a useful predictor for the therapeutic efficacy of metoprolol on POTS in children.     

Density functional theory for the selective adsorption of small molecules on a surface modified with polymer brushes

A density functional method based on weighted density approximation is extended to study the selective adsorption of small molecules on a surface modified with end-grafted square-well chains. The excess part of the Helmholtz free energy functional is divided into two components: the hard sphere repulsion and the square-well attraction. The equation of state for hard sphere chain fluids developed by Liu et al. is used to calculate the repulsive part of the excess Helmholtz free energy functional, and the equation of state for square-well chain fluid with variable range developed by Li et al. is employed to calculate the attractive part. With this theoretical model, we examine the physical properties of the grafted polymer and the selective adsorption of small molecules on the modified surface.     

Extensive hydrolysis of N-formyl-L-methionyl-L-leucyl-L-[3H] phenylalanine by human polymorphonuclear leukocytes. A potential mechanism for modulation of the chemoattractant signal

Chemoattractant receptors on human polymorphonuclear leukocytes (PMNs) stimulate a series of important biological responses. In an attempt to better understand the mechanism of stimulus response coupling of chemoattractant receptors, the kinetics of N-formyl-L-methionyl-L-leucyl-L-[3H]phenylalanine (fMet-Leu-[3H]Phe) binding to PMNs was evaluated. Unexpectedly, extensive degradation of the ligand was found to occur rapidly at 37 degrees C. Exposure of 10(7) cells/ml to 10 nM fMet-Leu-[3H]Phe led to the specific uptake of approximately 1% of the ligand within 10 min, while approximately 50% of the extracellular chemoattractant was hydrolyzed to free amino acids. Under the same conditions, isolated plasma membranes equivalent to 2.5 X 10(7) PMNs/ml bound specifically approximately 1% of the ligand and degraded about one-half of it primarily to Leu-[3H]Phe. The fMet-Leu-[3H]Phe hydrolysis commenced with no apparent latency, yet disobeyed first order kinetics as a 100-fold excess unlabeled ligand enhanced the initial consumption rate of 10 nM fMet-Leu-[3H]Phe by 500-fold, yielding an enhancement of the relative hydrolysis to approximately 70%. 1-butanol at 0.25%, which accelerates chemotaxis but inhibits superoxide anion and lysosomal enzyme secretion, reduced the hydrolysis to about 15% independent of the fMet-Leu-[3H]Phe specific activity. Lysosomal secretion could not mediate the hydrolysis process, since the supernatants of PMNs exposed either to 10 nM of 1 microM fMet-Leu-Phe reveal no degradation capacity toward fMet-Leu-[3H]Phe. These data indicate that the hydrolysis of the chemoattractant occurs at the cell surface and is dependent on the plasma membrane physical state. This phenomenon may well modulate the chemotactic signal due to its ability to profoundly alter the level of the chemoattractant proximate to the cell surface.