A whole genome scan to map QTL for milk production traits and somatic cell score in Canadian Holstein bulls

The detection and mapping of genetic markers linked to quantitative trait loci (QTL) can be utilized to enhance genetic improvement of livestock populations. With the completion of the bovine genome sequence assembly, single nucleotide polymorphisms (SNP) assays spanning the whole bovine genome and research work on large scale identification, validation and analysis of genotypic variation in cattle has become possible. The objective of the present study was to perform a whole genome scan to identify and map QTL affecting milk production traits and somatic cell scores using linkage disequilibrium (LD) regression and 1536 SNP markers. Three and 18 SNP were found to be associated with only milk yield (MY) at a genome and chromosome wise significance (p < 0.05) level respectively. Among the 21 significant SNP, 16 were in a region reported to have QTL for MY in other dairy cattle populations and while the rest five were new QTL finding. Four SNP out of 21 are significant for the milk production traits (MY, fat yield, protein yield (PY), and milk contents) in the present study. Six and nine SNP were associated with PY at a genome and chromosome wise significant (p < 0.05) level respectively. Three and 17 SNP were found to be associated with FY at a genome and chromosome wise significant (p < 0.05) level. Five and seven SNP were mapped with somatic cell score at a genome and chromosome wise significant (p < 0.05) level respectively. The results of this study have revealed QTL for MY, PY, protein percentage, FY, fat percentage, somatic cell score and persistency of milk in the Canadian dairy cattle population. The chromosome regions identified in this study should be further investigated to potentially identify the causative mutations underlying the QTL.

Testosterone inhibits the activity of peroxisome proliferator-activated receptor gamma in a transcriptional transaction assay

Emerging evidences suggest that testosterone is an important regulator of body fat mass in men. However, the mechanism underlying the regulation of body composition by testosterone is not well understood. The paper demonstrates testosterone inhibited the activity of peroxisome proliferator-activated receptor gamma (PPARgamma), which controls the adipogenic differentiation and lipid metabolism. Pre-inhibition of androgen receptor did not influence the inhibition of PPARgamma activity by testosterone. Moreover, pre-treatment with testosterone attenuated the insulin-induced up-regulation of PPARgamma activity. These results provide a novel mechanism for the effect of testosterone on fat mass control.

Pancreatic cancer stem cells and EMT in drug resistance and metastasis

Pancreatic cancer (PC) is an aggressive malignancy with one of the worst outcomes among all cancers. It is the fourth leading cause of cancer death in the United States with a very low five-year survival rate. The high mortality of PC could, in part, be due to their drug resistance characteristics and high propensity for metastasis. Recently, cancer stem cells (CSCs) and epithelial-mesenchymal transition (EMT)-type cells, which shares molecular characteristics with CSCs, have been believed to play critical roles in drug resistance and cancer metastasis as demonstrated in several human malignancies including PC. Thus, the discovery of molecular knowledge of drug resistance and metastasis in relation to CSCs and EMT in PC is becoming an important area of research, and such knowledge is likely to be helpful in the discovery of newer drugs as well as designing novel therapeutic strategies for the treatment of PC with better outcome. In this brief review, we will summarize the current knowledge regarding the CSCs and EMT in the context of drug resistance and metastasis in PC, the molecular events occurring in CSCs and EMT, and the design of novel therapeutic strategies targeting CSCs and EMT-type cells to increase drug sensitivity and suppression of metastasis toward better treatment outcome of patients diagnosed with PC.

Thalidomide has a therapeutic effect on interstitial lung fibrosis: evidence from in vitro and in vivo studies

The objective of this study was to investigate the effects of thalidomide (THD) on interstitial lung fibrosis (ILF). In vitro, human fetal lung fibroblast (HFL-F) to myofibroblast (MF) trans-differentiation was induced by transforming growth factor (TGF)-beta1. The effects of THD on trans-differentiation process or differentiated MF were evaluated by measuring hydroxyproline (HYP) content by alkaline hydrolysis colorimetry, alpha-smooth muscle actin (alpha-SMA) protein by Western blot and alpha-SMA and pro-collagen III mRNA expressions by semi-quantitative reverse transcription-polymerase chain reaction; in vivo, a mouse model of ILF was generated by daily subcutaneous injection of bleomycin (BLM) in female C3H mice. Gastric perfusion of THD began 1 week prior to injection and lasted for 8 weeks. Lung specimens were harvested at different time-points (1, 4, 6 and 8 weeks) for pathology and immunohistochemistry examination. The HYP content, alpha-SMA and pro-collagen III mRNA expressions were also assessed. THD inhibited the up-regulation of HYP protein, pro-collagen III mRNA and alpha-SMA protein induced by TGF-beta1 in HFL-F cells, and additionally inhibited pro-collagen III mRNA expression on trans-differentiated MF. THD reduced HYP synthesis in the lung tissues of BLM-treated mice at week 4, and slightly reduced the numbers of alpha-SMA-positive cells. THD had an effect on ILF models both in vitro and in vivo.

Imaging features of hepatic angiomyolipomas on real-time contrast-enhanced ultrasound

The aim of this study was to evaluate the imaging features of hepatic angiomyolipoma (AML) on contrast-enhanced ultrasound (CEUS). The imaging features of 12 pathologically proven hepatic AML lesions in 10 patients who had undergone baseline ultrasound (BUS) and CEUS examinations were evaluated retrospectively. The enhancement extent, pattern and dynamic change, along with the enhancement process, on CEUS were analysed. The diagnostic results of BUS and CEUS before pathological examination were also recorded. The results showed that 75% (9/12) of the AML lesions exhibited mixed echogenicity on BUS and most showed remarkable hyperechogenicity in combination with a hypoechoic or anechoic portion. Arterial flow signals were detected in 75% (9/12) of the lesions on colour Doppler imaging. On CEUS, 66.7% (n = 8) of the 12 lesions exhibited hyperenhancement in the arterial phase, slight hyperenhancement (n = 2) or isoenhancement (n = 6) in the portal phase, and slight hyperenhancement (n = 1) or isoenhancement (n = 7) in the late phase. Three (25%) lesions exhibited hyperenhancement in the arterial phase and hypoenhancement in both portal and late phases. One (8.3%) lesion exhibited hypoenhancement throughout the CEUS process. Before pathological examination with BUS, only 3 (25%) lesions were correctly diagnosed as hepatic AML. Conversely, on CEUS, correct diagnoses were made for 66.8% (8/12) of hepatic AMLs. Therefore, arterial hyperenhancement and subsequent sustained enhancement on CEUS were found in the majority of hepatic AMLs. The combination of BUS and CEUS leads to the correct diagnosis in the majority of hepatic AMLs, and is higher than the success rate achieved by BUS alone.

Observation of a novel orbital selective Mott transition in Ca(1.8)Sr(0.2)RuO(4)

We observed a novel orbital selective Mott transition in Ca(1.8)Sr(0.2)RuO(4) by angle-resolved photoemission. While two sets of dispersing bands and the Fermi surface associated with the doubly degenerate d(yz) and d(zx) orbitals are identified, the Fermi surface associated with the wider d(xy) band is missing as a consequence of selective Mott localization. Our theoretical calculations demonstrate that this orbital selective Mott transition is mainly driven by the combined effects of interorbital carrier transfer, superlattice potential, and orbital degeneracy, whereas the bandwidth difference plays a less important role.

Haplotype-based case-control study of receptor (calcitonin) activity-modifying protein-1 gene in cerebral infarction

Calcitonin gene-related peptide (CGRP) receptor is a complex molecule that consists of calcitonin receptor-like receptor and receptor activity-modifying protein-1 (RAMP1). It was recently reported that RAMP1-deficient mice (RAMP1(-/-)) showed inflammatory responses with a transiently significant increase in serum CGRP levels and proinflammatory cytokines when compared with RAMP1(+/+) mice. The aim of this study was to investigate the relationship between the human RAMP1 gene and cerebral infarction (CI) using single-nucleotide polymorphisms (SNPs) in a Japanese population. We selected six SNPs in the human RAMP1 gene (rs3754701, rs3769048, rs7557078, rs1584243, rs10199956 and rs7590387) and performed a case-control study using each SNP and haplotype in 171 CI patients and 234 controls. There were no significant differences in overall distribution of genotype and allele frequencies of the SNPs between the CI and control groups. However, there was a significant difference in overall distribution between the CI and control groups (P<0.001) in the haplotype-based case-control study with the combinations of rs3754701-rs3769048-rs7590387. The T-A-C susceptibility haplotype for CI was significantly more frequent than in the control group (P=0.0024). The results suggest that the T-A-C haplotype is a genetic marker for CI, and that RAMP1 or neighbouring genes are associated with increased susceptibility to CI.

The purinergic receptor P2Y, G-protein coupled, 2 (P2RY2) gene associated with essential hypertension in Japanese men

P2RY2 has an important function in the regulation of blood pressure by activating adenosine triphosphate (ATP). The aim of this study was to investigate the association between the human P2RY2 gene and essential hypertension (EH) through a haplotype-based case-control study that included two gender groups. The 273 EH patients and 255 age-matched controls were genotyped for five single-nucleotide polymorphisms (SNPs) of the human P2RY2 gene (rs4944831, rs1783596, rs4944832, rs4382936 and rs10898909). Data were analysed for men and women separately and then as a combined total group. For the total and the men only groups, the genotype distribution of the T allele of rs4944831 and the recessive model (GG vs TG+TT) of rs4944831 differed significantly between the EH patients and controls (P=0.028 and 0.019; P=0.009 and 0.008, respectively). Logistic regression showed that for the total and men groups, the TG+TT genotype of rs4944831 was more prevalent in EH patients than in the controls (P=0.026 and 0.011, respectively). For men, the overall distribution of the haplotype (SNP2-SNP4-SNP5) was significantly different between the EH patients and the controls (P=0.006). As compared with controls, the frequency of the T-A-G haplotype was significantly higher, whereas the T-C-G haplotype was significantly lower for the EH patients (P=0.001 and 0.014, respectively). In conclusion, the present results indicate that rs4944831 and the T-A-G haplotype of the human P2RY2 gene might be genetic markers for EH in Japanese men.

Evaluation of the cytotoxicity of a two photon absorbing fluorescence compound on human HepG2 cells and its application to tracking human hepatic cancer cells in mice

Small organic dyes have been applied widely in fluorescence imaging techniques for biomedical research. We investigated the cytotoxicity of a novel fluorescent dye, trans-4-(N-2-hydroxyethyl-N-ethyl amino)-4'-(dimethyl amino) stilbene (DMAHAS), on human hepatocellular carcinoma (HepG2) cells using methyl thiazolyl tetrazolium(MTT), a neutral red assay, a Coomassie brilliant blue assay, and flow cytometric analysis. Our results showed that DMAHAS had live cell permeability, stable cytosolic localization and no significant cytotoxicity to HepG2 cells. We explored its application further for tumor cell tracking in a human liver tumor xenograft mouse model. Tumor xenografts were examined by fluorescence imaging and conventional histological methods. In addition, a method based on DMAHAS release was developed for tumor-specific cytotoxicity analysis. Our study indicated that DMAHAS is a reliable probe for tumor tracking and fluorescence imaging.

Glucose transporter 2 expression: prevention of streptozotocin-induced reduction in beta-cells with 5-thio-D-glucose

The effect of streptozotocin (STZ) on the glucose transporter 2 (GLUT2) expression in beta-cells was investigated in vitro and in vivo. By Western blot analysis, a gradually decreasing GLUT2 expression was found in islets prepared from C57BL/6 male mice that had received multiple low doses of STZ (MD-STZ) for induction of autoimmune diabetes. Reduction of GLUT2 expression correlated with the number of STZ injections administered and preceded development of hyperglycemia. When hyperglycemia had developed, GLUT2 expression was extremely reduced. In vitro, incubation of isolated islets with STZ resulted in a time- and dose-dependent reduction of beta-cell GLUT2 expression. In vivo, pretreatment of MD-STZ recipients with intraperitoneal injections with 5-thio-D-glucose (5-T-G) just before each of the STZ injections prevented MD-STZ-induced beta-cell GLUT2 reduction and hyperglycemia development. In vitro, preincubation of islet cultures with 5-T-G also prevented STZ-induced GLUT2 reduction. Unlike STZ, equimolar concentrations of methylnitrosourea (MNU), the aglycone moiety of STZ, failed to alter GLUT2 expression in vitro. In conclusion, our data demonstrate that STZ-induced beta-cell GLUT2 reduction was prevented by 5-T-G both in vitro and in vivo in the MD-STZ diabetes model. The noxious effect of STZ on GLUT2 expression is most likely facilitated through its glucose moiety, because MNU lacked to do so. Presumably, in autoimmune MD-STZ diabetes the GLUT2 glucose transporter might be a key target structure for STZ subtoxicity and diabetogenicity, which converge with subsequent immune reactions to beta-cell destruction.

Detection and analysis of Borna disease virus in Chinese patients with neurological disorders

BACKGROUND AND PURPOSE

Borna disease virus (BDV) is a neurotropic RNA virus that is known to cause neurological disturbances in various animal species, potentially even humans. However, the association between BDV infection and human neurological disorders remains unclear.

METHODS

Between August 2005 and March 2006, 65 patients with neurological disorders were enrolled into our study. The presence of BDV p24 RNA from peripheral blood mononuclear cells (PBMCs) was investigated by using nested reverse transcriptase PCR (RT-PCR) assay.

RESULTS

Borna disease virus p24 RNA was detected from PBMCs in six patients with viral encephalitis by using nested RT-PCR assay. However, BDV p24 RNA was not detected in patients with multiple sclerosis or peripheral nerve diseases.

CONCLUSION

There might be possible associations between BDV infection and human viral encephalitis.