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Standard operating procedures (SOP) in experimental stroke research: SOP for middle cerebral artery occlusion in the mouse
Get PDFRecently, systematic reviews have found quantitative evidence that low study quality may have introduced a bias into preclinical stroke research. Monitoring, auditing, and standard operating procedures (SOPs) are already key elements of quality control in randomized clinical trials and will hopefully be widely adopted by preclinical stroke research in the near future. Increasingly, funding bodies and review boards overseeing animal experiments are taking a proactive stance, and demand auditable quality control measures in preclinical research. Every good quality control system is based on its SOPs. This article introduces the concept of quality control and presents for the first time an SOP in experimental stroke research
Double burden of malnutrition among urban Bengalee adolescent boys in Midnapore, West Bengal, India
Get PDFMalnutrition is an important public health problem worldwide. Therefore a study was undertaken to assess the prevalence of adolescent thinness, overweight and obesity in Midnapore town, West Bengal, India. A total of 974 adolescent boys aged 10-18 years were selected following multistage cluster sampling method from three higher secondary schools. Data was collected using pretested questionnaire following standard technique. Presence of thinness was evaluated using the cut-off values of international survey as suggested by Cole et al (2007). While overweight and obesity was determine by using international cut-off values develop by Cole et al (2000) based on international surveys as recommended by IOTF. Overall the prevalence of thinness, overweight and obesity were 20.8%, 14.9% and 3.8%, respectively. This study developed age specific smooth BMI percentile values using LMS method. Moreover, the study also developed BMI cut-off values to define thinness, overweight and obesity. In conclusion, the present analyses indicated that the prevalence of adolescent undernutrition is still a major problem. In addition, there was also an emerging trend for overweight/obesity, thereby indicating a double burden of malnutrition as observed in other developing countries
Applying of novel subtraction method Genetically Directed Differential Subtraction Chain (GDDSC) in plant genomes
No full textWe present a simple subtraction procedure of GDDSC as a modification of the original DSC and GDRDA methods. Genetically Directed Differential Subtraction Chain (GDDSC) is a process by which highly related genomes are compared in order to isolate tags carrying the polymorphisms. 
To detect specific DNA fragment (tag), we can then monitor offspring plants for efficient molecular breeding. The GDDSC protocol was applied to isolation of new sex related clones from cucumber plants (_Cucumis_ _sativus_ L.) and new tissue culture response clones from rye (_Secale_ _cereale_ L.). The newly identified tags, obtained by GDDSC represent pools of candidate genes and other sequences, which could serve as potential markers for requested traits
Tutorial: Query Federation with SWObjects
No full textQuery federation is a way to make use of distributed data sources on the Web, including many SPARQL endpoints as well as relational databases. SWObjects makes use of mapping rules represented as SPARQL Constructs to dynamically rewrite the terms and predicates of a SPARQL query into corresponding terms in another vocabulary and connect the resulting query with the appropriate service for answering the query. SWObjects can also rewrite SPARQL queries in SQL, effectively including relational databases alongside SPARQL endpoints in a linked data federation. The author of SWObjects, Eric Prud'hommeaux, is the W3C staff contact for the W3C Health Care and Life Sciences Interest Group (HCLS IG) and will give the tutorial via a teleconference connection, with assistance from Helena Deus (University of Texas) and M. Scott Marshall (HCLS IG co-chair)
Anti-HIV therapy: pipeline approaches and future directions
Get PDFHuman immunodeficiency virus (HIV), with about 30 million deaths and double infections (in developing countries), is an open challenge today for global scientists. Developing safe and effective measurements against it has become the prime need of hour. Though, putting it at health priority, various efforts like chemotherapy, vaccines and others are attempted globally over last decade. Consequently, highly active antiretroviral therapy was introduced but fails to completely block the viral replication due to drug resistance and various other severe side effects. The antigenic variability and lack of appropriate experimental models is the major obstacle in the development of an ever effective treatment against HIV. However, to overcome the present hurdles and to emerge a preventive HIV vaccine efforts at various platforms are done. A renewed, coordinated research, preclinical studies, clinical trials together with sufficient long term scientific and commercial commitments are made. Few of the therapeutic efforts viz. RNA interference (RNAi) based replication arrest of HIV, viral enzymes’ inhibitors, nanotechnology based HIV control and various preclinically trialed vaccines are reviewed in this paper. Also, the observed toxicity of existing therapeutic regimen, key challenges and future prospects for the development of better tolerated prophylactic HIV-1 vaccine are discussed
Computational Studies Of Huntington Protein: Classification & Binding Pattern Determination
No full textHuntington's disease (HD) is a dominantly inherited neurodegenerative disorder characterized by progressive motor deficits, psychiatric deterioration, worsening chorea, cognitive impairment due to neuronal cell loss in the basal ganglia, cerebral cortex, and its fragments interactions with themselves and other biomolecules that results in aggregates , transcriptional repression , oxidative injury and mitochondrial dysfunction . The repeat domain of Huntingtin interacting protein (HIP) 14 (PDB id 3eu9) is used to study the structure based drug design. We made the selection of 50 different small molecules which were screened out through various fixed parameters and applied descriptors to generate the model for molecules that shows the drug likeness properties. We also used a docking algorithm to further find out the most suitable molecule which specifically binds to the HIP and refined this by simulation studies. The classifier is used to validate the training set of molecules with the test set. The interaction energy between the ligand and the protein was calculated and analyzed by using the semiempirical method. The results indicated that protein model can account for the regioselectivity of this protein towards the known ligands and van der Waals interactions were the driving force for the ligand binding. Several key residues were identified to be responsible for the binding of nitrogen containing ligands with HIP. These findings provide useful information for the detailed characterization of the biological roles of HIP and binding pattern determination for the new set of analogues
Subtyping of Dengue Viruses using Return Time Distribution based Appproach
Get PDFDengue virus (DENV) is the causative agent of Dengue Hemorrhagic Fever and Dengue Shock Syndrome, and continues to represent a major public health hazard. DENVs are antigenically classified in four serotypes and each serotype is further divided into respective genotypes. The association between DENV subtypes and the kind & severity of disease caused by them is known. Experimental and computational approaches for subtyping are routinely used for the purpose of diagnosis and treatment of DENV, in addition to the study of phylodynamics. All virus-specific molecular subtyping tools make use of sequence alignments at backend. But as the volume of molecular data increases, alignment-dependent methods become computationally intensive. Hence, the need for alternative efficient approaches for subtyping of viruses becomes apparent. Recently, the concept of Return time distribution (RTD) was proposed and validated for alignment-free clustering and molecular phylogeny. The RTD-based approach is extended here for the subtyping of DENVs. 
Subtyping methodology involves compilation of curated genomic data of known subtypes, computing RTD of these sequences at different levels of k-mers, derivation a distance matrix and clustering. The subtype of the unknown is predicted based on its clustering with known subtypes.
Dataset consisting of 1359 DENV genomes with sequence identity (>92%) were clustered using the RTD based approach at k=5. Serotype specific clades, despite geographical and temporal variation in the dataset, were observed with 100% accuracy. The method was also found to be efficient in terms of time and implementation, apart from accuracy in the subtyping of DENV
Chemotherapy effects on brain glucose metabolism at rest
Get PDFBackground: A growing number of studies reports that chemotherapy may impair brain functions inducing cognitive changes which can persist in a subset of cancer survivors. 
Aims: To investigate the neural basis of the chemotherapy-induced neurobehavioral changes by means of metabolic imaging and voxel-based statistical parametric mapping analyses.
Methods: We studied the resting brain [18]FDG-PET/CT images of 43 adult cancer patients with solid (n=12, 28%) or hematologic malignancies (n=31, 72%); 12 patients were studied prior to chemotherapy (No chemotherapy) while treated patients were divided into two matched subgroups: Early High (<9 months after chemotherapy, >6 chemotherapy cycles, n=10), and Late Low (>9 months after chemotherapy, <6 chemotherapy cycles, n=21). 
Findings: Compared to No chemotherapy, the Early High subgroup showed a significant bilateral (p<0.05) lower regional cerebral metabolic rate of glucose metabolism in both the prefrontal cortices and white matter, cerebellum, posterior medial cortices and limbic regions. A similar pattern emerged in the Early High versus Low Late comparison, while no significant result was obtained in the Low Late versus No chemotherapy comparison. The number of cycles and the post-chemotherapy time were negatively and positively correlated, respectively, with a set of these same brain regions. 
Interpretation: The present study shows that chemotherapy induces significant transient changes in the glucose metabolism of multiple cerebral cortical and white matter regions with a prevailing involvement of the prefrontal cortex. The severity of these changes are significantly related with the number of chemotherapy cycles and a subset of brain regions seems to present longer lasting, but more subtle, metabolic changes
Quantitative detection of _Potato virus Y_ in potato plants and aphids - Discussion of diverse applications in potato research
Get PDFEvery year potato growers worldwide complain about severe yield losses caused by _Potato virus Y_ (PVY). Therefore, PVY along with _Potato leafroll virus_ belongs to the most important potato viruses. There are three main strains of PVY: PVY^O^, PVY^N^ and PVY^C^. However, also recombinant forms exist such as PVY^N^Wilga and PVY^NTN^, both of which increase in importance due to their potential to displace the non-recombinant strains at a high percentage. They appear also in mixed infections. In recent years PCR and qPCR assays were developed to differentiate PVY isolates. In order to identify PVY isolates by PCR often large amplicons have to be generated which requires the input of expensive enzymes. On the other hand, qPCR assays until now do not allow the differentiation between PVY^N^Wilga and PVY^NTN^. 

For the discrimination between PVY^O^/PVY^N^Wilga and PVY^N^/PVY^NTN^ a qPCR assay was developed, which allows the differentiation and highly efficient quantification of both strains and recombinants, respectively. For this purpose dual-labeled hydrolysis probes tagged with different fluorophores were designed. The assay is suitable for many different applications, for example safety research on genetically modified (GM) potato plants. The goal of this research is to determine whether genetic modification causes changes in resistance to viruses. Two different GM cultivars were examined for signs of altered resistance to an infection with PVY in comparison to their near-isogenic lines and three reference cultivars. Reference cultivars are included to determine the baselines for resistance and thus to be able to decide if the changes could represent a biological risk. The plants to be investigated were mechanically inoculated with PVY^N^Wilga or PVY^NTN^ and analyzed by means of the developed assay after two weeks. The results of the experiment indicate that the differences in virus titer between the reference cultivars are higher than between the GM potatoes and their isogenic lines. Therefore, in our experiments the GM potato plants showed no alteration in PVY resistance to neither one of the tested strains.

Since _Myzus persicae_ is one of the most important vectors transmitting PVY, the developed assay will also be applied to the quantification of PVY particles in aphids. The displacement of PVY^O^ and PVY^N^ by PVY^N^Wilga and PVY^NTN^ may be due to a difference in efficiency of transmission by _M. persicae_. Therefore, the objective is to test whether more virus particles of the recombinant forms in comparison to the non-recombinant strains PVY^O^ and PVY^N^ bind in the stylets of _M. persicae_. 

A third possible application of the developed assay may be of interest in potato breeding. The exact quantification of PVY particles in plants allows the classification of resistance in potato plants. It is possible to estimate whether a resistance is extreme or not. Extreme resistance is characterized by the absence or presence of very low amounts of virus particles in plants several days after inoculation. When testing the plants for PVY infection by ELISA, often unspecific reactions occur which makes it difficult to differentiate between plants weakly infected and plants very weakly infected. An exact quantification of the PVY titer gives more certainty for the determination of the resistance type.

In conclusion, the developed assay is an efficient and low-cost method that allows the differentiation and quantification of PVY^O^/PVY^N^Wilga on the one hand and PVY^N^/PVY^NTN^ on the other hand with high throughput. The method can be utilized for a wide range of applications in potato research.

A Quantitative Approach to Investigating the Hypothesis of Prokaryotic Intron Loss
Get PDFUsing a novel method, we show that ordered triplets of motifs usually associated with spliceosomal intron recognition are underrepresented in the protein coding sequence of complete Thermotogae, archaeal and bacterial genomes. The underrepresentation observed does not extend to the noncoding strand, suggesting that the cause of the asymmetry is related to mRNA rather than DNA. Our data do not suggest that the underrepresentation is due to gene transfer from eukaryotes. We speculate that one possible explanation for these observations is that the protein coding sequence of Thermotogae, Archaea and Bacteria was at some time in the past subjected to selection against certain motifs appearing in an order which might initiate splicing in environments harboring a functional spliceosome. This is consistent with, but certainly does not prove, a hypothetical scenario in which at least some prokaryote lineages once possessed a functional spliceosome. Thus, we present a new quantitative method, observations obtained using the method, and a speculative discussion of a possible explanation of the observations