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With the deep integration of software collaborative development and social networking, social coding represents a new style of software production and creation paradigm. Because of their good flexibility and openness, a large number of external contributors have been attracted to the open-source communities. They are playing a significant role in open-source development. However, the open-source development online is a globalized and distributed cooperative work. If left unsupervised, the contribution process may result in inefficiency. It takes contributors a lot of time to find suitable projects or tasks from thousands of open-source projects in the communities to work on. In this paper, we propose a new approach called “RepoLike,” to recommend repositories for developers based on linear combination and learning to rank. It uses the project popularity, technical dependencies among projects, and social connections among developers to measure the correlations between a developer and the given projects. Experimental results show that our approach can achieve over 25% of hit ratio when recommending 20 candidates, meaning that it can recommend closely correlated repositories to social developers.

A discretization method is used in pre-stretching simulation to separate an aluminum alloy thick plate into layers. When the equivalent plastic strain in each layer is defined according to the residual stresses during quenching, the yield strength model can be developed to estimate its yield strength. Again, the curve of elasticity modulus is fitted in the light of the experimental data, which can reveal how the elasticity modulus changes with plastic deformation. Finally, in consideration of the non-uniformity of yield strength and elasticity modulus, the pre-stretching of the quenched 7075 aluminum alloy thick plate is taken as an example to numerically simulate the value and distribution of residual stresses at the pre-stretching ratio of 1.8%, 2.2% and 2.5%, respectively. It is known from the simulated results that, by using the proposed method in this paper, the obtained results of the distribution and magnitude of the residual stresses are in good agreement with the experimental measurements.

Temozolomide (TMZ) is a novel cytotoxic alkylating agent for chemotherapy of malignant gliomas. However, intrinsic or acquired resistance to TMZ often defines poor efficacy of chemotherapy in malignant gliomas. A growing number of studies indicate that expression of O(6)-methylguanine-DNA methyltransferase (MGMT) is one of the principal mechanisms responsible for this chemoresistance. In the present study, we evaluated the relationship between expression of MGMT and resistance to TMZ. We generated a TMZ-resistant cell line, U251/TR, by stepwise (8 months) exposure of parental U251 cells to TMZ. The resistance to TMZ was quantified using SRB assay. MGMT expression was evaluated at mRNA (RT-PCR) and protein (Western blot) levels. U251/TR cells showed increased (~ sevenfold) resistance to TMZ. The MGMT expression (both mRNA and protein) was significantly (P < 0.01) increased in U251/TR cells compared with parental U251 cells. Further, MGMT expression fluctuated during exposure of U251/TR cells to TMZ. The resistance of U251/TR cells to TMZ could be overcome by application of elevated doses of TMZ when MGMT expression was at the lowest level. In conclusion, our results demonstrate that the primary mechanism responsible for resistance of U251/TR cells to TMZ is associated with increased expression of MGMT. Resistance of malignant gliomas to TMZ can be overcome by synchronizing metronomic TMZ regimen with MGMT expression.

Objective: To explore the clinicpathologic features and MRI manifestations of the thoracic lumbar tuberculosis by underwenting MRI and pathological examinations. Methods: 34 cases of Thoracic lumbar tuberculosis were collected which underwent MRI examination and confirmed by pathology or treatment of anti-TB drugs, the clinical cure from June 2008 to June 2012 in our hospital. The first MRI was performed on all patients, to determine the MRI findings, and surgical treatment for pathological examination in order to determine the pathological features. Results: 34 patients with 81 vertebral involvement, in which two adjacent vertebral involvement is the common, accounting for 72.25%, vertebral showed uneven long T1, long T2 signal. Intervertebral disc abnormalities accounted for 90.17%, the performance showed long T1, long T2 signal changes in the intervertebral disc damage, often accompanied by disc space narrowing or disappear. Paraspinal abscess accounted for 90.67%, often more than vertebra, up and down across one or more vertebral bodies showed long T1, long T2 signal. The vertebrae were damaged kyphosis or (and) the posterior longitudinal ligament abscess caused by the dural sac and spinal column with pressure accounted for 74.72%. In enhanced scan, vertebrae, intervertebral discs showed heterogeneous enhancement, paraspinal abscess was curved or ring enhancement. The pathological diagnosis may be obvious to confirm the degree of swelling and lesions. Conclusion: By doing the MRI and pathologic examinations, it can determine the clinical and pathological features and MRI findings of spinal tuberculosis patients with Thoracic lumbar spinal tuberculosis, and lay a reliable foundation for the treatment of the subsequent treatment.

The db/db mice are perfect animal models of type 2 diabetes which have been widely used. The phenotypes of severe obesity, hyperphagia, polydipsia, and polyuria are due to a spontaneous mutation of the leptin receptor (Lepr). The course of the disease is markedly influenced by genetic background, which is more serious in the C57BLKS/J background. And there are many other spontaneous mutations in different sites of Lepr, which produce a series of animal models of obesity, including db(3J)/ db(3J) mice, db(5j)/db(5J) mice, db(pas)/db(pas) mice, Zucker fa/fa rats, and Koletsky fa(k)/fa(k) rats, etc. These rodents appear similar hyperphagia and severe obesity, but different levels of blood glucose, kidney damage and reproductive ability, providing profuse material to investigate the complex function of Lepr. Here we review the history of the discovery of the leptin signaling pathway, the abnormal phenotypes of db/db mice in metabolic, reproductive, immune, etc. Discuss their research applications, reproductive strategy, genotyping guideline, the phenotypic diversity of those animal models with Lepr spontaneous mutation and their mutation patterns, respectively.

To generate the skeletal muscle-specific transforming growth factor beta receptor II (TbetaR II) gene knockout mice for the research on the function of the TbetaR II gene in skeletal muscles.TbetaR II (flox/flox) mice were generated using embryonic stem cell technology. The MCK-Cre mice were engineered containing Cre recombinase under the control of creatine kinase (MCK) muscle-specific promoter. TbetaR II (flox/flox) mice were crossed with MCK-Cre mice generating TbetaR II (flox/flox)/MCK-Cre double Tg mice. And then, TbetaR II (flox/wt) /MCK-Cre(+) double Tg mice were crossed with TbetaR II (flox/flox) mice to generate TbetaR II (flox/flox)/MCK- Cre(+) mice genetically ablating TbetaR II in cre-expressing skeletal muscle cells.As predicted, mice lacking TbetaR II by gene targeting in skeletal muscles were generated first in the world using Cre/loxP system. TbetaR II null mutant mice were viable, fertile and showed apparently normal development.

To investigate the expression of CD133 and CD34 in different parts of glioblastoma and its margin and explore the invasive path of glioma stem cells within the tumor and surrounding tissue.The surgical specimens were collected from the core of mass, junctional zones between tumor and peritumoral edematous areas and edematous areas in 52 patients with glioblastoma. Immunohistochemical cell staining and Western blot were employed to evaluate the expression of CD133 in different specimens while immunohistochemistry was used to detect the CD34-microvessel postforming. A correlation analysis was performed between them.The expression of CD133 was not detected in the control groups while the scores were 7.3 ± 1.4, 5.2 ± 1.1, 2.7 ± 1.0 in junctional zones, tumor cores and edematous areas with immunohistochemistry and 0.79 ± 0.03, 0.38 ± 0.01, 0.20 ± 0.04 with Western blot respectively. There were significant differences between different groups (P0.05). Under light microscope, the CD133-positive cells frequently forming perivascular pseudorosettes were dense in junctional zones and mostly clustered near the microvessels in tumor cores and scattered in edematous areas. At a high magnification (200×), the CD34-MVD (/HP) values were 31.3 ± 4.0, 21.8 ± 2.6, 15.3 ± 2.4, 4.7 ± 1.5 respectively in junctional zones, tumor cores, edematous areas and control tissues. Significant differences were also found in these groups (P0.05). The expression level of CD133-positive cell was positively correlated with the distribution of CD34-microvessels (r = 0.948, P0.05).Glioma stem cells tend to assemble in the junctional zones where the microvessels are enriched. There is probably an intimate nourishing relationship with the microvessels. The distribution of glioma stem cells may be related with the invasiveness within glioblastoma.

To investigate the utility of hMena, a family of enabled/vasodilator-stimulated phosphoprotein (Ena/VASP), we sought to characterize the expression profile and distribution characteristics of hMena in a large panel of glioma samples and determine whether hMena expression levels might correlate with the pathological grade of glioma.Sixty-five specimens of glioma with different pathological grades and five control brain tissues were collected. In 6 of the 21 glioblastoma patients, multi-specimens were obtained respectively from the main tumor mass, the junction zone between the tumor and the normal tissue, and adjacent brain tissue 1.5 cm away from the tumor boundary under assistance of neuronavigation system during the operation. Immunohistochemistry was used to detect the expression and distribution characteristics of hMena. hMena expression was analyzed by Western blot in 20 specimens.The hMena expression was negative in control brain tissue but positive in different grades of glioma. The expression rate of hMena was positively correlated with the increasing grade of the World Health Orgnization (WHO) classification (r(s)=0.682, P=0.000). hMena was located in cytoplasm. Positive cells only distributed around the vessels within the tumor mass in low grade glioma, while in high grade glioma, these cells were able to be detected not only in the tumor but also in the boundary zone and adjacent brain parenchyma. In the tumor mass, hMena expressed highly and diffusedly. In the junction zone, hMena positive cells formed radiolitic pattern around the vessels. In adjacent brain parenchyma, single positive cell was scattered. hMena expression was markedly elevated in Grade III and IV glioma compared with Grade II and I.Our data suggested that the expression of hMena is closely related to malignant grade of glioma. hMena can label the migrating cells, and indicate the migrating path of glioma cells from the tumor to adjacent tissue along with the vascular basement membranes and tracts of white matter.

To detect the expression level of stage-specific genes in Leishmania promastigotes and amastigotes.Total RNAs were isolated from Leishmania amazonensis stationary promastigotes and three sources of amastigotes: freshly obtained from mouse skin lesions, infected J774.G8 macrophages, and transformed from the cultured promastigotes. mRNAs were conversely transcribed into cDNA with SuperScripII reverse transcriptase and oligo dT primers. The polymerase chain reaction (PCR) was used to amplify the specific fragments of amastigote-specific nuclease (P-4) and promastigote-specific membrane glycoprotein (GP-46). PCR products were analyzed in 1.5% agarose gel.A P-4-specific band (273 bp) was observed in all three types of amastigotes with similar density, but it was almost undetectable in promastigotes. In contract, a GP-46-specific band (325 bp) was expressed at a higher level in promastigotes than in all three types of amastigotes.Promastigote-derived amastigotes express high level of P-4-specific gene and can be used as a source of amastigotes for biochemical and immunological studies.

To study the effect of ischemic preconditioning (PC) and pharmacological preconditioning with adenosine or diazoxide on ischemia-reperfusion (IR) injury in the limbs of rats.According to different treatment received before ischemic-reperfusion injury, 66 SD rats were divided into 6 groups including a normal control and a ischemia-reperfusion control group, IP10 group in which the rats received 10-min ischemia followed by 10-min interval for reperfusion for 3 times before IR, IP5 group in which the rats were subjected to 5-min ischemia with 5-min reperfusion intervals for 3 times before IR, adenosine (Ade) pretreatment group and diazoxide (Dia) pretreatment group. Except the normal control group, which consisted of 6 rats, each group contained 12 rats, and IR injury was induced by blocking the blood flow in bilateral limbs for 4 h, followed by reperfusion for 2 or 24 h when twitch and spastic contractility of the tibialis anterior muscle and serum creatine phosphokinase (CPK) were measured.In IP5 and Ade pretreatment group, the twitch tension of the tibialis anterior muscle of the rats was significantly enhanced after 2 and 24 h of reperfusion, achieving the level of the normal control. The twitch tension was also enhanced in rats of IP10 group at 24 h, but at 2 h, though with less effectiveness than that in IP5 and Ade group. Dia pretreatment reduced twitch and tetanic contraction forces of the tibialis anterior muscle after 2 h of reperfusion, but obviously improved twitch tension at 24 h. Improvement in the tetanic tension, however, was seen in none of the groups. Serum CPK of IP5, IP10 and Ade groups after 2 and 24 h while Dia at only 24 h of reperfusion was obviously lower than that of IR group.Ischemic and Ade preconditioning can protect the limbs of rats from ischemia-reperfusion injury, and Dia has delayed protective effect. IP5 is superior than IP10 and Ade PC can produce similar effect to that of ischemic PC.