Transverse spin current in the s-wave/p-wave Josephson junction

We report a theoretical study on spin transport in the hybrid Josephson junction composed of singlet s-wave and triplet p-wave superconductor. The node of the triplet pair potential is considered perpendicular to the interface of the junction. Based on a symmetry analysis, we predict that there is no net spin density at the interface of the junction but instead a transverse mode-resolved spin density can exist and a nonzero spin current can flow transversely along the interface of the junction. The predictions are numerically demonstrated by means of the lattice Matsubara Green's function method. It is also shown that, when a normal metal is sandwiched in between two superconductors, both spin current and transverse mode-resolved spin density are only residing at two interfaces due to the smearing effect of the multimode transport. Our findings are useful for identifying the pairing symmetry of the p-wave superconductor and generating spin current.

Effect of downregulated β-catenin on cell proliferative activity, the sensitivity to chemotherapy drug and tumorigenicity of ovarian cancer cells

The role of Wnt/β-catenin signaling pathway in the etiology and/or progression of ovarian cancer has been well documented. It was demonstrated that ovarian cancer constantly exhibit constitutive activation of canonical Wnt signaling, usually as a result of oncogenic mutations that stabilize and dysregulate the β-catenin protein. In this study, we transfected an expression vector-based small hairpin RNA (shRNA) targeting to β-catenin encoding gene into human A2780 ovarian cancer cells to investigate the effects of β-catenin knockdown on biological characteristics of ovarian cancer cells. The results showed that β-catenin shRNA expression resulted in decreased β-catenin mRNA and protein expression in the transfected A2780 cells, inhibition of cellular proliferation, decreased capability of clonogenicity in the plating and the soft agar, and increased sensitivities to chemotherapy drugs vincristine, paclitaxel and cisplatin compared to untransfected cells. Importantly, we found that shRNA-mediated knockdown of β-catenin strongly decreases tumour growth of human A2780 ovarian cancer cells in xenografts. These results demonstrate that β-catenin might be an effective therapeutic target for human ovarian cancer treatment.

Genetic diversity of Tibetan goats of Plateau type using microsatellite markers

Abstract. The 10 microsatellite markers (XBM7, XBM11, XBM16, XBM19, XBM24, XBM31, XBM84, TGLA53, SRCRSP-10 and ILS005) were selected to investigate the genetic diversity of Tibetan goat of Plateau type (NM, n=108), and the other 5 goat populations, i.e., Tibetan goat of Valley type (TG, n=36), Baiyu black goat (BY, n=36), Jianchang black goat (JC, n=36), Meigu goat (MG, n=36) and Xinjiang goat (XJ, n=32) were served as control. The mean polymorphism information content, heterozygosity and effective allele number of these 6 populations were 0.660/0.777/4.476, 0.716/0.797/4.9416, 0.631/0.673/3.061, 0.649/0.680/3.125, 0.629/0.680/3.125 and 0.561/0.793/4.840 respectively. The allele frequencies of Tibetan goat of plateau type in 10 microsatellite loci were greatly different with other 5 goat populations. The 6 goat populations were grouped into three distinct clusters: the Tibetan goat cluster (NM goat and TG goat), Sichuan goat cluster (JC goat, MG goat and BY goat), and Xinjiang goat cluster (XJ goat). These 3 distinct clusters were finally clustered together. The genetic differences among populations were in accordance with their geographical and historical origins.

MicroRNA-mediated breast cancer metastasis: from primary site to distant organs

The recent upsurge of interest in microRNA (miRNA) is partly attributed to the discovery of the novel roles of miRNAs in many physiological and pathological processes, including tumor development. Research on breast cancer metastasis has also focused on the concept of miRNA, which can act either as promoters or as suppressors of metastases. This review will focus on a series of recent studies that demonstrate the involvement of miRNAs in breast cancer metastasis and will briefly describe various pathways of miRNA-regulated metastasis. Finally, future prospects will be discussed for the potential role of miRNAs as predictive markers and therapeutic agents for patients with breast cancer metastases.

Detection of three human adenovirus species in adults with acute respiratory infection in China

Human adenoviruses (HAdVs) are recognized as causal agents in a wide range of human diseases. However, researchers lack sufficient data on the exact HAdV species and serotypes associated with adult acute respiratory tract infections (ARTIs). To detect and characterize HAdV infections in adults in China, clinical specimens were collected from 10,310 adults with ARTIs from May 2005 to July 2010. The partial HAdV hexon gene was amplified by polymerase chain reaction (PCR), sequenced, and phylogenetically analyzed. HAdVs were detected in 86 samples (0.8%), of which 67 (77.9%) were species B (HAdV-3, -7, -11, and -14), 7 (8.1%) were species C (HAdV-1, -2, and -6), and 12 (14%) were species E (HAdV-4). HAdV-3 was the most frequently detected serotype (41/86, 47.7%), followed by HAdV-7 (13/86, 15.1%), HAdV-4 (12/86, 14.0%), and HAdV-11 (11/86, 12.8%). Patients 14-25 years old (60.5%) exhibited a higher rate of adenovirus detection than older patients. Co-infections with other respiratory viruses were observed in samples positive for HAdV species B and E. Human rhinovirus was the most commonly found virus in patients with HAdV infection. These findings provide baseline data for the surveillance and control of HAdV infection in China.

Glioma Growth Inhibition In Vitro and In Vivo by Single Chain Variable Fragments of the Transferrin Receptor Conjugated to Survivin Small Interfering RNA

Inhibition of survivin by small interfering RNA (siRNA) can delay glioma growth. To enhance the effect of survivin-siRNA on intercranial glioma, a conjugate of siRNA-survivin and single-chain variable fragment (scFv) of the transferrin receptor (TfR) was constructed and its effects assessed in vitro and in vivo. Survivin-siRNA and the survivin-siRNA/scFv-TfR conjugate were constructed and used successfully to inhibit glioma U87 cell proliferation and enhance apoptosis in vitro. The molecular constructs were administered to an established U87 orthotopic mouse model. Western blot analysis and immunohistochemistry of the glioma tissues showed that survivin protein levels were strongly suppressed by the survivin-siRNA/scFv-TfR conjugate in vivo. Furthermore, survivin-siRNA/scFv-TfR prolonged the survival time of mice more than survivin-siRNA. In conclusion, the survivin-siRNA/scFv-TfR conjugate efficiently enhanced the effects of survivin-siRNA on glioma suppression in vivo, confirming the applicability of antibody-targeted molecular therapies for treating human brain tumours.

An improved polymerase chain reaction method for genetic testing of spinocerebellar ataxia type 3

The development of a reliable PCR assay for genetic testing of spinocerebellar ataxia type 3. Touchdown PCR conditions were tested and different primer sets were evaluated with genomic DNA from blood sample of patients suffering from spinocerebellar ataxia type 3 (SCA3). An improved PCR assay was developed with a new set of primers and using the optimized touchdown PCR protocol. This new assay had been successfully employed in the screening of one identificated SCA3 family. Results from the present study document a simple and reliable PCR assay for genetic testing of SCA3. Strategies used in the present study may find applications in the optimization of PCR assay for triplet expansion with GC rich in the sequence context.

A new likelihood estimator and its comparison with moment estimators of individual genome-wide diversity

The inbreeding coefficient of an individual, F, is one of the central parameters in population genetics theory. It has found important applications in evolutionary biology, conservation and ecology, such as the study of inbreeding depression. In the absence of detailed and reliable pedigree records, researchers have developed quite a few estimators to estimate F or the genome-wide homozygosity from genetic marker data. The statistical properties and comparative performances of these metrics are rarely known, however, which impedes an informed choice of the most appropriate one in practical applications. In this investigation, I propose a new likelihood F estimator that makes efficient use of marker information and takes into account of allelic dropouts, null alleles and prior knowledge of inbreeding. I compare the likelihood estimator with three moment estimators of F and three metrics of genomic homozygosity (or heterozygosity) by analysing both simulated and empirical datasets. It is shown that the likelihood estimator invariably outperforms the other estimators and metrics across all datasets analysed. For a typical dataset in heterozygosity-fitness correlation studies involving 10-20 microsatellites and 50 individuals, the correlation between the likelihood estimator and F (the simulated true inbreeding coefficient) is about 8 ∼ 35% higher than that between the moment estimators and F. A frequently applied metric, multilocus heterozygosity (MLH), and an F estimator based on the consideration of the proportion of alleles in homozygous conditions, [F R'), are shown to have particularly poor performances. The low correlation between MLH and fitness traits, which is widely observed in numerous empirical studies, might be partially caused by the adoption of this inefficient estimator of genomic inbreeding.