Heat-inactivated C. pneumoniae organisms are not atherogenic

We have previously shown that infection with Chlamydia pneumoniae can significantly exacerbate atherosclerotic lesions in LDLR-/- mice concurrently fed a high cholesterol diet in 6 or 9 months. We now report that a period of 4 month was sufficient for demonstrating the C. pneumoniae atherogenicity. However, heat inactivation of C. pneumoniae organisms completely abolished the ability of C. pneumoniae to exacerbate the atherosclerotic lesions, suggesting that viable organism infection may be required for the C. pneumoniae atherogenicity.     

The intermediary metabolite pyruvate attenuates stunning and reduces infarct size in in vivo porcine myocardium

The intermediary metabolite pyruvate has been shown to exert significant beneficial effects in in vitro models of myocardial oxidative stress and ischemia-reperfusion injury. However, there have been few reports of the ability of pyruvate to attenuate myocardial stunning or reduce infarct size in vivo. This study tested whether supraphysiological levels of pyruvate protect against reversible and irreversible in vivo myocardial ischemia-reperfusion injury. Anesthetized, open-chest pigs (n = 7/group) underwent 15 min of left anterior descending coronary artery (LAD) occlusion and 3 h of reperfusion to induce stunning. Load-insensitive contractility measurements of regional preload recruitable stroke work (PRSW) and PRSW area (PRSWA) were generated. Vehicle or pyruvate (100 mg/kg i.v. bolus + 10 mg x kg(-1) x min(-1) intra-atrial infusion) was administered during ischemia and for the first hour of reperfusion. In infarct studies, pigs (n = 6/group) underwent 1 h of LAD ischemia and 3 h of reperfusion. Group I pigs received vehicle or pyruvate for 30 min before and throughout ischemia. In group II, the infusion was extended through 1 h of reperfusion. In the stunning protocol, pyruvate significantly improved the recovery of PRSWA at 1 h (50 +/- 4% vs. 23 +/- 3% in controls) and 3 h (69 +/- 5% vs. 39 +/- 3% in controls) reperfusion. Control pigs exhibited infarct sizes of 66 +/- 1% of the area at risk. The pyruvate I protocol was associated with an infarct size of 49 +/- 3% (P < 0.05), whereas the pyruvate II protocol was associated with an infarct size of 30 +/- 2% (P < 0.05 vs. control and pyruvate I). These findings suggest that pyruvate attenuates stunning and decreases myocardial infarction in vivo in part by reduction of reperfusion injury. Metabolic interventions such as pyruvate should be considered when designing the optimal therapeutic strategies for limiting myocardial ischemia-reperfusion injury.     

Colorimetric method for identifying plant essential oil components that affect biofilm formation and structure

The specific biofilm formation (SBF) assay, a technique based on crystal violet staining, was developed to locate plant essential oils and their components that affect biofilm formation. SBF analysis determined that cinnamon, cassia, and citronella oils differentially affected growth-normalized biofilm formation by Escherichia coli. Examination of the corresponding essential oil principal components by the SBF assay revealed that cinnamaldehyde decreased biofilm formation compared to biofilms grown in Luria-Bertani broth, eugenol did not result in a change, and citronellol increased the SBF. To evaluate these results, two microscopy-based assays were employed. First, confocal laser scanning microscopy (CLSM) was used to examine E. coli biofilms cultivated in flow cells, which were quantitatively analyzed by COMSTAT, an image analysis program. The overall trend for five parameters that characterize biofilm development corroborated the findings of the SBF assay. Second, the results of an assay measuring growth-normalized adhesion by direct microscopy concurred with the results of the SBF assay and CLSM imaging. Viability staining indicated that there was reduced toxicity of the essential oil components to cells in biofilms compared to the toxicity to planktonic cells but revealed morphological damage to E. coli after cinnamaldehyde exposure. Cinnamaldehyde also inhibited the swimming motility of E. coli. SBF analysis of three Pseudomonas species exposed to cinnamaldehyde, eugenol, or citronellol revealed diverse responses. The SBF assay could be useful as an initial step for finding plant essential oils and their components that affect biofilm formation and structure.     

Tubulin inhibitors. Synthesis and biological activity of HTI-286 analogs with B-segment heterosubstituents

Modifications of the B-segment of HTI-286 (2) produced a class of analogs incorporating heteroatom-substituents. The structure-activity relationship was studied. Analogs bearing methylsulfide and fluoride groups exhibited potency comparable to that of the parent compound HTI-286 and to paclitaxel in cytotoxicity assays against KB-3-1 cell lines. These analogs were more potent than paclitaxel against P-glycoprotein expressing KB-8-5 and KB-V1 cell lines. Several analogs showed strong inhibition of tubulin polymerization.     

SNPicker: a graphical tool for primer picking in designing mutagenic endonuclease restriction assays

Simple, low-cost and accurate genotyping methods for single nucleotide polymorphisms (SNPs) are in high demand in the post-genome-sequencing era. We present a graphical tool called SNPicker, implemented in Java, which significantly facilitates the design of mutagenic endonuclease restriction assays. SNPicker uses the online NEB REBASE to automatically scan for all possible designs of mutagenic primers that can facilitate the picking of mismatched PCR primers to artificially introduce or abolish a restriction site at the target SNP site. We successfully applied SNPicker in designing endonuclease restriction assays for 14 SNPs for the MTHFR gene, the Coagulation Factor II gene and the Coagulation Factor V gene. The SNP assays designed using SNPicker were cross-validated using the MassARRAY technology.     

A statistical method for identifying differential gene-gene co-expression patterns

MOTIVATION: To understand cancer etiology, it is important to explore molecular changes in cellular processes from normal state to cancerous state. Because genes interact with each other during cellular processes, carcinogenesis related genes may form differential co-expression patterns with other genes in different cell states. In this study, we develop a statistical method for identifying differential gene-gene co-expression patterns in different cell states. RESULTS: For efficient pattern recognition, we extend the traditional F-statistic and obtain an Expected Conditional F-statistic (ECF-statistic), which incorporates statistical information of location and correlation. We also propose a statistical method for data transformation. Our approach is applied to a microarray gene expression dataset for prostate cancer study. For a gene of interest, our method can select other genes that have differential gene-gene co-expression patterns with this gene in different cell states. The 10 most frequently selected genes, include hepsin, GSTP1 and AMACR, which have recently been proposed to be associated with prostate carcinogenesis. However, genes GSTP1 and AMACR cannot be identified by studying differential gene expression alone. By using tumor suppressor genes TP53, PTEN and RB1, we identify seven genes that also include hepsin, GSTP1 and AMACR. We show that genes associated with cancer may have differential gene-gene expression patterns with many other genes in different cell states. By discovering such patterns, we may be able to identify carcinogenesis related genes.     

人尾加压素Ⅱ对大鼠脑微循环的影响

目的:探讨尾加压素Ⅱ(UII)对于大鼠软脑膜微循环的影响.方法:健康成年SD大鼠随机分为对照组、生理盐水(NS)、UII(10-7mol/L)、去甲肾上腺素(NA,10-6mol/L)、UII(10-7mol/L) NA(10-6mol/L)等五组,采用活体微循环观测技术观察大鼠软脑膜微血管内径、血流速度等微循环参数,采用激光多普勒血流量仪测定软脑膜血流量的变化.结果:正常对照组软脑膜细动脉和细静脉血管内径分别为(35.4±3.6)μm和(40.6±8.5)μm,UII组于滴加UII(10-7mol/L)后即刻细动脉和细静脉出现收缩,1 min时细动脉和细静脉收缩达到高峰,血管内径分别为(25.6±3.4)μm和(23.4±3.3)μm (与正常对照组比较,P均<0.05);细动、静脉内血流速度无明显变化(与正常对照组比较P均>0.05);软脑膜血流量于滴加UII(10-7mol/L)后1 min开始升高,5 min达到高峰(3.5±0.4 )PU 值,正常对照组(2.3±0.6)PU值(P<0.05).结论:UII可以使大鼠软脑膜微血管收缩,血流量增加.