Taxonomic and genetic assessment of captive White-Handed Gibbons (Hylobates lar) in Peninsular Malaysia with implications towards conservation translocation and reintroduction programmes

Conservation translocation and reintroduction for the purpose of repopulating and reinforcing extirpated or depleted populations has been recognised as an important conservation tool, particularly for gibbon conservation in the immediate future. Feasibility assessments involving multiple factors, including taxonomic and genetic assessment of rescued and captive gibbons, are imperative prior to translocation and reintroduction programmes. In this study, we attempt to determine the subspecies and origin of captive Hylobates lar, White-handed gibbons, from Peninsular Malaysia to assist in future translocation and reintroduction programmes. A total of 12 captive and rescued H. lar samples were analysed using the control region segment of mitochondrial DNA. Sequence analyses and phylogenetic trees constructed using neighbour-joining, maximum likelihood, Bayesian inference, and network methods congruently differentiate all 12 captive individuals used in this study from other H. lar subspecies suggesting that these individuals belong to the H. lar lar subspecies. In addition, two populations of H. l. lar were observed: (1) a southern population consisting of all 12 individuals from Peninsular Malaysia, and (2) a possible northern population represented by three individuals (from previous studies), which might have originated from the region between the Isthmus of Kra, Surat Thani-Krabi depression, and Kangar-Pattani. Our findings suggest that the complete control region segment can be used to determine the subspecies and origin of captive H. lar.

AN EFFICIENT TECHNIQUE FOR RETINAL VESSEL SEGMENTATION AND DENOISING USING MODIFIED ISODATA AND CLAHE

Retinal damage caused due to complications of diabetes is known as Diabetic Retinopathy (DR). In this case, the vision is obscured due to the damage of retinal tinny blood vessels of the retina. These tinny blood vessels may cause leakage which affect the vision and can lead to complete blindness. Identification of these new retinal vessels and their structure is essential for analysis of DR. Automatic blood vessels segmentation plays a significant role to assist subsequent automatic methodologies that aid to such analysis. In literature most of the people have used computationally hungry a strong preprocessing steps followed by a simple thresholding and post processing, But in our proposed technique we utilize an arrangement of light pre-processing which consists of Contrast Limited Adaptive Histogram Equalization (CLAHE) for contrast enhancement, a difference image of green channel from its Gaussian blur filtered image to remove local noise or geometrical object, Modified Iterative Self Organizing Data Analysis Technique (MISODATA) for segmentation of vessel and non-vessel pixels based on global and local thresholding, and a strong post processing using region properties (area, eccentricity) to eliminate the unwanted region/segment, non-vessel pixels and noise that never been used to reject misclassified foreground pixels. The strategy is tested on the publically accessible DRIVE (Digital Retinal Images for Vessel Extraction) and STARE (STructured Analysis of the REtina) databases. The performance of proposed technique is assessed comprehensively and the acquired accuracy, robustness, low complexity and high efficiency and very less computational time that make the method an efficient tool for automatic retinal image analysis. Proposed technique perform well as compared to the existing strategies on the online available databases in term of accuracy, sensitivity, specificity, false positive rate, true positive rate and area under receiver operating characteristic (ROC) curve.

Automatic crystal centring procedure at the SSRF macromolecular crystallography beamline

X-ray diffraction is a common technique for determining crystal structures. The average time needed for the solution of a protein structure has been drastically reduced by a number of recent experimental and theoretical developments. Since high-throughput protein crystallography benefits from full automation of all steps that are carried out on a synchrotron beamline, an automatic crystal centring procedure is important for crystallographic beamlines. Fully automatic crystal alignment involves the application of optical methods to identify the crystal and move it onto the rotation axis and into the X-ray beam. Crystal recognition has complex dependencies on the illumination, crystal size and viewing angles due to effects such as local shading, inter-reflections and the presence of antifreezing elements. Here, a rapid procedure for crystal centring with multiple cameras using region segment thresholding is reported. Firstly, a simple illumination-invariant loop recognition and classification model is used by slicing a low-magnification loop image into small region segments, then classifying the loop into different types and aligning it to the beam position using feature vectors of the region segments. Secondly, an edge detection algorithm is used to find the crystal sample in a high-magnification image using region segment thresholding. Results show that this crystal centring method is extremely successful under fluctuating light states as well as for poorly frozen and opaque samples. Moreover, this crystal centring procedure is successfully integrated into the enhancedBlu-Icedata collection system at beamline BL17U1 at the Shanghai Synchrotron Radiation Facility as a routine method for an automatic crystal screening procedure.

Hoop Membrane Stress Analysis of Elbow-Pipe under Single Internal Pressure

In the article, a kind of regional force balance method based on plates and shells theories of elastic mechanics are applied to study the hoop membrane stress of the elbow-pipe, while internal pressure is as a single load. By learning the static balance equation ΣFx=0 of a micro-region segment of pipe shell, it is found that axial membrane stress σ1 is perpendicular to x-direction and has no effect to equilibrium condition, here axial stress σ1is discussed explicitly. It shows that, the hoop membrane stress σh of the elbow is the times of straight tube’s hoop stress.

The Immunogenicity of BCR/ABL+ Cells Is Dominated by BCR/ABL-Regulated Antigens and Is Impaired by the Inhibition of BCR/ABL Kinase Activity.

The inhibition of BCR/ABL kinase activity by imatinib mesylate (IM, STI571, Gleevec®) is the standard therapy for patients with Philadelphia chromosome+ (Ph+) chronic myeloid leukemia (CML). However, the long term treatment with IM or other BCR/ABL kinase inhibitors may be limited due to the development of resistant disease and accumulating side effects. Immunotherapeutical approaches directed against Ph+ CML may overcome these problems. So far, the research to develop an immunotherapy against Ph+ leukemia focused on the BCR-ABL fusion protein, giving the promising opportunity to stimulate cytotoxic T lymphocytes against the joining region segment of p210 BCR/ABL. However, only a limited number of peptides spanning the fusion region is endogenously processed and presented in context with HLA class I molecules. In contrast, the constitutively active BCR/ABL kinase leads to the upregulation and activation of multiple proteins, which may subsequently result in the expression of different, probably leukemia-associated antigens on the cell surface of BCR/ABL-positive malignant cells. In this study, we investigated the immunogenicity of antigens upregulated by BCR-ABL kinase activity, and verified the capacity of these antigens to induce an anti-leukemia T cell response in vitro. We performed CD8+ T-cell stimulations with dendritic cells transfected with mRNA coding BCR/ABL wild-type (WT). Following two stimulations, the proliferating T-cell populations were analyzed for cytokine secretion (IFN-γ) in response to target cells expressing either BCR/ABL WT or a kinase deficient (KD, K1172R) variant of BCR/ABL. With this experimental setting it was possible to compare the immunogenic potential of antigens upregulated by BCR/ABL with the immunogenicity of the BCR/ABL protein itself. We were not able to activate T-cell populations directed against either the breakpoint-region of BCR/ABL or the BCR- or ABL part of the fusion protein. In contrast, we show here that the constitutively active kinase domain of BCR/ABL has a key role in enhancing the immunogenicity of BCR/ABL+ cells. A broad, HLA-dependent T-cell immune response specifically directed against BCR/ABL regulated antigens was detected. The inhibition of BCR/ABL kinase activity by IM significantly impaired the immunogenicity of BCR/ABL+ cells. We found the same T-cell reactivity pattern in several healthy donors and a CML patient. This is the first study demonstrating the major contribution of the BCR/ABL kinase domain to the immunogenicity of BCR/ABL+ cells as T-cell responses against these cells are dominated by BCR/ABL regulated antigens, and not by BCR/ABL itself. These results may contribute to the design of clinical vaccination trials for the treatment CML patients with minimal residual disease, e.g. following successful induction therapy with BCR/ABL inhibitors.

VECTORIZATION AND PRECISE REFRACTIONS IN BEAM TRACING

In this paper we propose two improvements to the beam tracing method, one is to reduce the final redundant-drawing of pixel fragments into the frame buffer, and the other is to use Snell's law instead of the tangent law. It is well known that the ray tracing scheme is one of the most effective methods for high quality CG image synthesis. The beam tracing method was introduced because traditional ray tracing algorithms have a significant calculation cost. In the improved method, the projection screen is recursively divided into non-overlapping coherent region segments based on the coherence of the ray-trace-tree structure of a given scene, and an image can be synthesized after the segmentation process by tracing one or several rays in each region segment. We introduced Snell's law for the refractions of the rays. Therefore, we can reduce the computational cost of ray tracing, eliminate the extra calculations caused by overlapping polygons on a screen, and increase the quality of CG images generated by our proposed method.

Natural Isolates of Simian Virus 40 from Immunocompromised Monkeys Display Extensive Genetic Heterogeneity: New Implications for Polyomavirus Disease

ABSTRACT Simian virus 40 (SV40) DNAs in brain tissue and peripheral blood mononuclear cells (PBMCs) of eight simian immunodeficiency virus-infected rhesus monkeys with SV40 brain disease were analyzed. We report the detection, cloning, and identification of five new SV40 strains following a quadruple testing-verification strategy. SV40 genomes with archetypal regulatory regions (containing a duplication within the G/C-rich regulatory region segment and a single 72-bp enhancer element) were recovered from seven animal brains, two tissues of which also contained viral genomes with nonarchetypal regulatory regions (containing a duplication within the G/C-rich regulatory region segment as well as a variable duplication within the enhancer region). In contrast, PBMC DNAs from five of six animals had viral genomes with both regulatory region types. It appeared, based on T-antigen variable-region sequences, that nonarchetypal virus variants arose de novo within each animal. The eighth animal exclusively yielded a new type of SV40 strain (SV40-K661), containing a protoarchetypal regulatory region (lacking a duplication within the G/C-rich segment of the regulatory region and containing one 72-bp element in the enhancer region), from both brain tissue and PBMCs. The presence of SV40 in PBMCs suggests that hematogenous spread of viral infection may occur. An archetypal version of a virus similar to SV40 reference strain 776 (a kidney isolate) was recovered from one brain, substantiating the idea that SV40 is neurotropic as well as kidney-tropic. Indirect evidence suggests that maternal-infant transmission of SV40 may have occurred in one animal. These findings provide new insights for human polyomavirus disease.