A zebrafish orthologue (whnb) of the mouse nude gene is expressed in the epithelial compartment of the embryonic thymic rudiment

The cloning and characterization of the zebrafish orthologue of the mouse nude (Whn/Foxn1) gene, whnb are reported. A previously described Whn-like gene from zebrafish, now designated as whna, is shown to be the orthologue of the mouse Foxn4 gene. The whnb gene is specifically expressed in the thymic rudiment of zebrafish embryos at day 3 after fertilization, whereas the whna gene is expressed in eye and brain structures. Whnb expression is maintained in cloche mutants, where endothelial and haematopoietic cell differentiation is defective, but absent in casanova mutants where endoderm formation is impaired. In adult thymi, whnb is expressed throughout cortical and medullary areas, whereas whna expression is observed in rare cell clusters only. Our results provide the first specific marker for the epithelial compartment of the zebrafish thymus.     

Regulation of norepinephrine-induced proliferation in cardiac fibroblasts by interleukin-6 and p42/p44 mitogen activated protein kinase

Norepinephrine (NE) is involved in many cardiovascular diseases such as congestive heart failure. We have recently reported that NE had a comitogenic effect in isolated cardiac fibroblasts, and that it activated p42/p44 mitogen activated protein kinase (MAPK). This study was designed to characterize a possible mechanism involved in the proliferative effect of NE. Isolated rat cardiac fibroblasts were exposed to NE (10M) for up to 8 h, and interleukin-6 (IL-6) expression was measured by Ribonuclease Protection Assay and Western blotting. The activity of p42/p44^MAPK was analyzed by Western blotting. Cell number was assessed by use of a Coulter Counter. IL-6/GAPDH mRNA was increased by NE in a time-dependent manner reaching 23 fold stimulation after 1 h compared to untreated samples. Immunoreactivity to IL-6 was not found in controls. After 16h of exposure to NE, IL-6 protein was detected. It further increased up to 48 h. The effect of NE on IL-6 mRNA was abolished by the -adrenoceptor blockers propranolol, metoprolol (₁) and ICI 118.551 (₂), but not by the -adrenoceptor blockers prazosin (₁) and yohimbine (₂). The MAPK-inhibitor PD98059 suppressed the NE-induced MAPK activation in a concentration-dependent fashion after 5 min, attenuated the NE-induced IL-6 expression after 2 h, and suppressed the proliferative effect of NE from 53 to 18% after 48 h. Recombinant IL-6 caused an increase in proliferation by 31% after 48 h. Simultaneous application of the IL-6 antibody reduced the NE-induced proliferation to 34%, and completely prevented the IL-6 induced effect. These results suggest that NE induces proliferation of rat cardiac fibroblasts in part by increasing the expression of IL-6 through regulation of MAPK.     

Madin–Darby canine kidney cells are increased in aerobic glycolysis when cultured on flat and stiff collagen‐coated surfaces rather than in physiological 3‐D cultures

We investigate the influence of the dimensionality and the biochemistry of the culture system on the cellular functionality by analyzing the protein expression levels in Madin–Darby canine kidney (MDCK) cells grown in 3‐D and 2‐D substrates. We cultured MDCK cells on a hard and flat 2‐D uncoated plastic surface, on a 2‐D collagen‐coated plastic surface and in 3‐D collagen gel and employed 2‐D gel electrophoresis, MALDI‐TOF‐MS, and LC‐MS/MS analysis to identify the differentially regulated proteins. We found significant differences in the expression of antioxidant proteins, actin‐binding proteins, glycolytic enzymes, and heat‐shock proteins/chaperons among the three types of cultures. While MDCK cells cultured in 3‐D collagen up‐regulate antioxidant proteins and proteins involved in the dynamic remodeling of the actin cytoskeleton, 2‐D collagen‐coated plastic surfaces induce the up‐regulation of glycolytic enzymes. Our data shows that the culture conditions have profound effects on the physiology of the cell. Culture in 3‐D collagen induces a differentiated polarized phenotype. In contrast, collagen‐coated 2‐D substrates favor a tumor‐like phenotype with increased glycolysis. Thus, the suitability of 2‐D cultures to study the physiological behavior of cells, especially in drug discovery, bioprocessing, and toxicology, should be carefully reconsidered.     

Genetic portrait of Lisboa immigrant population from Cabo Verde with mitochondrial DNA analysis

Journal of Genetics -     

Association of 25-Hydroxyvitamin D status and genetic variation in the vitamin D metabolic pathway with FEV1 in the Framingham Heart Study

Background

Vitamin D is associated with lung function in cross-sectional studies, and vitamin D inadequacy is hypothesized to play a role in the pathogenesis of chronic obstructive pulmonary disease. Further data are needed to clarify the relation between vitamin D status, genetic variation in vitamin D metabolic genes, and cross-sectional and longitudinal changes in lung function in healthy adults.

Methods

We estimated the association between serum 25-hydroxyvitamin D [25(OH)D] and cross-sectional forced expiratory volume in the first second (FEV₁) in Framingham Heart Study (FHS) Offspring and Third Generation participants and the association between serum 25(OH)D and longitudinal change in FEV₁ in Third Generation participants using linear mixed-effects models. Using a gene-based approach, we investigated the association between 241 SNPs in 6 select vitamin D metabolic genes in relation to longitudinal change in FEV₁ in Offspring participants and pursued replication of these findings in a meta-analyzed set of 4 independent cohorts.

Results

We found a positive cross-sectional association between 25(OH)D and FEV₁ in FHS Offspring and Third Generation participants (P = 0.004). There was little or no association between 25(OH)D and longitudinal change in FEV₁ in Third Generation participants (P = 0.97). In Offspring participants, the CYP2R1 gene, hypothesized to influence usual serum 25(OH)D status, was associated with longitudinal change in FEV₁ (gene-based P < 0.05). The most significantly associated SNP from CYP2R1 had a consistent direction of association with FEV₁ in the meta-analyzed set of replication cohorts, but the association did not reach statistical significance thresholds (P = 0.09).

Conclusions

Serum 25(OH)D status was associated with cross-sectional FEV₁, but not longitudinal change in FEV₁. The inconsistent associations may be driven by differences in the groups studied. CYP2R1 demonstrated a gene-based association with longitudinal change in FEV₁ and is a promising candidate gene for further studies.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-015-0238-y) contains supplementary material, which is available to authorized users.     

High throughput screening of hydrolytic enzymes from termites using a natural substrate derived from sugarcane bagasse

Background

Short rotation coppice willow is a potential lignocellulosic feedstock in the United Kingdom and elsewhere; however, research on optimising willow specifically for bioethanol production has started developing only recently. We have used the feedstock Salix viminalis × Salix schwerinii cultivar 'Olof' in a three-month pot experiment with the aim of modifying cell wall composition and structure within the stem to the benefit of bioethanol production. Trees were treated for 26 or 43 days with tension wood induction and/or with an application of the cellulose synthesis inhibitor 2,6-dichlorobenzonitrile that is specific to secondary cell walls. Reaction wood (tension and opposite wood) was isolated from material that had received the 43-day tension wood induction treatment.

Results

Glucan content, lignin content and enzymatically released glucose were assayed. All measured parameters were altered without loss of total stem biomass yield, indicating that enzymatic saccharification yield can be enhanced by both alterations to cell wall structure and alterations to absolute contents of either glucan or lignin.

Conclusions

Final glucose yields can be improved by the induction of tension wood without a detrimental impact on biomass yield. The increase in glucan accessibility to cell wall degrading enzymes could help contribute to reducing the energy and environmental impacts of the lignocellulosic bioethanol production process.     

实验动物皮肤病原真菌检测方法的改良

目的对实验动物皮肤病原真菌2种培养方法进行了比较。方法将采集到的3只皮肤真菌感染病兔样品经由沙氏平皿法和沙氏试管斜面培养法分别进行培养。结果在3只真菌感染病兔中应用试管斜面法我们只检测到1例皮肤病原真菌阳性,而采用沙氏平皿法3例阳性全部检出。结论结合临床检测经验,我们认为本研究的沙氏平皿法优于沙氏试管斜面法,在实验动物皮肤病原真菌常规检测中具有推广应用价值。     

链脲佐菌素诱导长爪沙鼠Ⅰ型糖尿病模型的实验研究

目的探讨链脲佐菌素(STZ)诱导长爪沙鼠Ⅰ型糖尿病模型的可能性,并观察模型动物早期肾脏损害情况。方法雄性长爪沙鼠96只,随机分为正常对照组(NC组)、模型组1(DM1组)、模型组2(DM2组),DM1及DM2组沙鼠分别一次性腹腔注射100 mg/kg、200 mg/kg STZ,NC组注射等量柠檬酸盐缓冲溶液。注射STZ后1、2、4、6周末,分别监测沙鼠一般情况,血糖、胰岛素等血清学指标和尿液指标,并处死沙鼠进行胰腺和肾脏组织的病理学检查。结果注射STZ 24 h后,DM2组及DM1组部分沙鼠逐渐出现典型的"三多一少"症状,随着病程的发展,DM2组沙鼠持续高血糖,DM1组沙鼠血糖值与NC组差异有显著性(P0.05),但有下降趋势;DM2组沙鼠胰岛素显著性降低(P0.05),其他血清学指标及尿液指标均显著性升高(P0.05),DM1组沙鼠各指标差异无显著性。DM2组沙鼠及DM1组少数沙鼠胰腺组织中可见胰岛β细胞减少、空泡样变性等变化,DM2组沙鼠肾脏组织中出现肾小球基质增多,毛细血管襻扩张等病变,DM1组沙鼠肾脏组织未见明显变化。结论 STZ 200 mg/kg可成功诱导长爪沙鼠Ⅰ型糖尿病模型,在病程早期沙鼠肾脏结构和功能已经发生改变。