The Influence of Light Wavelength on Phase-Dependent Responsiveness of the Photoperiodic Clock in Migratory Blackheaded Bunting

We investigated the phase-dependent effects of light wavelength on photoperiodic clock in the migratory blackheaded bunting. Two experiments were performed, employing a skeleton paradigm (6 hours light : 6 hours darkness : 1 hour light : 11 hours darkness; 6L : 6D : 1L : 11D) at 37 ± 2 lux intensity. In the experiment 1, both 6 and 1 h light pulses were given at the same wavelength, 500 nm (green) or 650 nm (red). A group exposed to both pulses of white light served as control. In the experi-ment 2, the two light pulses were given at two different wavelengths, 6 h at 500 nm (green) and 1 h at 640 nm (red) in one group or vice-versa in the other. There was almost no photoinduction when both light pulses in experiment 1, or 1 h light pulse in experiment 2, were green. On the other hand, birds fattened and testes recrudesced when both the light pulses in experiment 1, or 1 h light pulse in experiment 2, were red. Birds receiving both pulses of white light in experiment 1 showed an intermediate response. Taken together, these results indicate that the photoperiodic clock in buntings is differentially responsive at its various circadian phases to different light wavelengths.     

Rapid Etiological Classification of Meningitis by NMR Spectroscopy Based on Metabolite Profiles and Host Response

Bacterial meningitis is an acute disease with high mortality that is reduced by early treatment. Identification of the causative microorganism by culture is sensitive but slow. Large volumes of cerebrospinal fluid (CSF) are required to maximise sensitivity and establish a provisional diagnosis.We have utilised nuclear magnetic resonance (NMR) spectroscopy to rapidly characterise the biochemical profile of CSF from normal rats and animals with pneumococcal or cryptococcal meningitis. Use of a miniaturised capillary NMR system overcame limitations caused by small CSF volumes and low metabolite concentrations. The analysis of the complex NMR spectroscopic data by a supervised statistical classification strategy included major, minor and unidentified metabolites.Reproducible spectral profiles were generated within less than three minutes, and revealed differences in the relative amounts of glucose, lactate, citrate, amino acid residues, acetate and polyols in the three groups. Contributions from microbial metabolism and inflammatory cells were evident. The computerised statistical classification strategy is based on both major metabolites and minor, partially unidentified metabolites. This data analysis proved highly specific for diagnosis (100% specificity in the final validation set), provided those with visible blood contamination were excluded from analysis; 6–8% of samples were classified as indeterminate.This proof of principle study suggests that a rapid etiologic diagnosis of meningitis is possible without prior culture. The method can be fully automated and avoids delays due to processing and selective identification of specific pathogens that are inherent in DNA-based techniques.     

Avian influenza virus directly infects human natural killer cells and inhibits cell activity

Natural killer (NK) cell is a key component of innate immunity and plays an important role in host defense against virus infection by directly destroying infected cells. Influenza is a respiratory disease transmitted in the early phase of virus infection. Evasion of host innate immunity including NK cells is critical for the virus to expand and establish a successful acute infection. Previously, we showed that human influenza H1N1 virus infects NK cells and induces cell apoptosis, as well as inhibits NK cell activity. In this study, we further demonstrated that avian influenza virus also directly targeted NK cells as an immunoevasion strategy. The avian virus infected human NK cells and induced cell apoptosis. In addition, avian influenza virion and HA protein inhibited NK cell cytotoxicity. This novel strategy has obvious advantages for avian influenza virus, allowing the virus sufficient time to expand and subsequent spread before the onset of the specific immune response. Our findings provide an important clue for the immunopathogenesis of avian influenza, and also suggest that direct targeting NK cells may be a common strategy used by both human and avian influenza viruses to evade NK cell immunity.

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Adiponectin,biomarkers of inflammation and changes in cardiac autonomic function: Whitehall II study

Background

Biomarkers of inflammation and adiponectin are associated with cardiovascular autonomic neuropathy (CAN) in cross-sectional studies, but prospective data are scarce. This study aimed to assess the associations of biomarkers of subclinical inflammation and adiponectin with subsequent changes in heart rate (HR) and heart rate variability (HRV) in non-diabetic and diabetic individuals.

Methods

Data are based on up to 25,050 person-examinations for 8469 study participants of the Whitehall II cohort study. Measures of CAN included HR and several HRV indices. Associations between baseline serum levels of high-sensitivity C-reactive protein (hsCRP), interleukin (IL)-6, IL-1 receptor antagonist (IL-1Ra) and adiponectin and 5-year changes in HR and six HRV indices were estimated using mixed-effects models adjusting for age, sex, ethnicity, body mass index (BMI), metabolic covariates and medication. A modifying effect of diabetes was tested.

Results

Higher levels of IL-1Ra were associated with higher increases in HR. Additional associations with measures of HRV were observed for hsCRP, IL-6 and IL-1Ra, but these associations were explained by BMI and other confounders. Associations between adiponectin, HR and HRV differed depending on diabetes status. Higher adiponectin levels were associated with more pronounced decreases in HR and increases in three measures of HRV reflecting both sympathetic and vagal activity, but these findings were limited to individuals with type 2 diabetes.

Conclusions

Higher IL-1Ra levels appeared as novel risk marker for increases in HR. Higher adiponectin levels were associated with a more favourable development of cardiovascular autonomic function in individuals with type 2 diabetes independently of multiple confounders.

     

Structure-based screening,ADMET profiling,and molecular dynamic studies on mGlu2 receptor for identification of newer antiepileptic agents

Structure-based screening approach targeting mGlu2 receptor was carried out to identify good chemical starting points for anti-epileptic therapy. Interactive modes of final 12 compounds identified on the basis of screening of Asinex library, binding energy analysis, ADME profiling with special emphasis for CNS ranges, and toxicity analysis were studied and showed good binding modes in the mGluR2-active site. Enrichment studies for validating screening protocol were carried out which gave ROC values 0.98 (AUC = 0.96) for SP, 0.97 (AUC = 0.95) for XP with BEDROC analysis. Our results indicate that all the 12 hits showed good CNS drug-like properties, have better binding free energy and ADME profile as compared to co-crystallized ligand with the best ligand hit retaining conserved hydrogen bond interactions with Ala-166, Thr-168, Ser-145, and Arg-61 residues in bilobatevenus fly-trap domain of mGluR2 receptor. Molecular dynamics simulations proved that the two potential hits, qualifying all screening parameters, are stable in the receptor active site pocket, confirming the potential of the identified hits as a specific target for mGluR2. Because the newly discovered mGluR2 agonists are structurally different with T_c values ranging from 0.57 to 0.92, all of them can be considered for further de novo design methods.     

Novel pyrazolo[1,5-a]pyridines with improved aqueous solubility as p110α-selective PI3 kinase inhibitors

As part of our investigation into pyrazolo[1,5-a]pyridines as novel p110α selective PI3 kinase inhibitors, we report a range of analogues with improved aqueous solubility by the addition of a basic amine. The compounds demonstrated comparable p110α potency and selectivity to earlier compounds but with up to 1000× greater aqueous solubility, as the hydrochloride salts. The compounds also displayed good activity in a cellular assay of PI3 kinase activity.     

Marker-assisted identification of restorer gene(s) in iso-cytoplasmic restorer lines of WA cytoplasm in rice and assessment of their fertility restoration potential across environments

Iso-cytoplasmic restorers possess the same male sterile cytoplasm as the cytoplasmic male sterile (CMS) lines, thereby minimizing the potential cyto-nuclear conflict in the hybrids. Restoration of fertility of the wild abortive CMS is governed by two major genes namely, Rf3 and Rf4. Therefore, assessing the allelic status of these restorer genes in the iso-cytoplasmic restorers using molecular markers will not only help in estimating the efficiency of these genes either alone or in combination, in fertility restoration in the hybrids in different environments, but will also be useful in determining the efficacy of these markers. In the present study, the efficiency of molecular markers in identifying genotypes carrying restorer allele of the gene(s) Rf3 and Rf4, restoring male fertility of WA cytoplasm in rice was assessed in a set of 100 iso-cytoplasmic rice restorers using gene linked as well as candidate gene based markers. In order to validate the efficacy of markers in identifying the restorers, a sub-set of selected 25 iso-cytoplasmic rice restorers were crossed with four different cytoplasmic male sterile lines namely, IR 79156A, IR 58025A, Pusa 6A and RTN 12A, and the pollen and spikelet fertility of the F₁s were evaluated at three different locations. Marker analysis showed that Rf4 was the predominant fertility restorer gene in the iso-cytoplasmic restorers and Rf3 had a synergistic effect on fertility restoration. The efficiency of gene based markers, DRCG-RF4-14 and DRRM-RF3-10 for Rf4 (87%) and Rf3 (84%) genes was higher than respective gene-linked SSR markers RM6100 (80%) and RM3873 (82%). It is concluded that the gene based markers can be effectively used in identifying fertility restorer lines obviating the need for making crosses and evaluating the F₁s. Though gene based markers are more efficient, there is a need to identify functional polymorphisms which can provide 100% efficiency. Three iso-cytoplasmic restorers namely, PRR 300, PRR 363 and PRR 396 possessing both Rf4 and Rf3 genes and good fertility restoration have been identified which could be used further in hybrid rice breeding.     

MCM9 binds Cdt1 and is required for the assembly of prereplication complexes

Prereplication complexes (pre-RCs) define potential origins of DNA replication and allow the recruitment of the replicative DNA helicase MCM2-7. Here, we characterize MCM9, a member of the MCM2-8 family. We demonstrate that MCM9 binds to chromatin in an ORC-dependent manner and is required for the recruitment of the MCM2-7 helicase onto chromatin. Its depletion leads to a block in pre-RC assembly, as well as DNA replication inhibition. We show that MCM9 forms a stable complex with the licensing factor Cdt1, preventing an excess of geminin on chromatin during the licensing reaction. Our data suggest that MCM9 is an essential activating linker between Cdt1 and the MCM2-7 complex, required for loading the MCM2-7 helicase onto DNA replication origins. Thus, Cdt1, with its two opposing regulatory binding factors MCM9 and geminin, appears to be a major platform on the pre-RC to integrate cell-cycle signals.     

A vector system for genomic FLAG epitope-tagging in Schizosaccharomyces pombe

The fission yeast Schizosaccharomyces pombe is a popular model organism to study various cellular processes, although research tools available for S. pombe are relatively inadequate. To facilitate genetic and biochemical investigation in S. pombe, we report here a system of vectors for genomic FLAG epitope-tagging. These vectors enable us to amplify gene-targeting fragments for integration into specific loci of the S. pombe genome. All vectors in this report were designed to express FLAG epitope-tagged proteins from their endogenous genomic loci. Vectors for N-terminal FLAG epitope-tagging allow us to control protein expression levels using the wild-type nmt1 promoter, its weaker derivatives, and the urg1 promoter. These vectors are available with various antibiotic markers including kanMX6, hphMX6, natMX6 and bleMX6, and the his3(+) marker. Vectors for C-terminal FLAG epitope-tagging were designed to express FLAG-fusion proteins under the control of their native promoters at their own genomic loci, allowing us to characterize protein functions under physiological conditions. These vectors are available with kanMX6, hphMX6, nat-MX6 and bleMX6 markers. The series of vectors described in this report should prove useful for protein studies in fission yeast.     

Is Exercise Protective Against Influenza-Associated Mortality?

Background

Little is known about the effect of physical exercise on influenza-associated mortality.

Methods and Findings

We collected information about exercise habits and other lifestyles, and socioeconomic and demographic status, the underlying cause of death of 24,656 adults (21% aged 30–64, 79% aged 65 or above) who died in 1998 in Hong Kong, and the weekly proportion of specimens positive for influenza A (H3N1 and H1N1) and B isolations during the same period. We assessed the excess risks (ER) of influenza-associated mortality due to all-natural causes, cardiovascular diseases, or respiratory disease among different levels of exercise: never/seldom (less than once per month), low/moderate (once per month to three times per week), and frequent (four times or more per week) by Poisson regression. We also assessed the differences in ER between exercise groups by case-only logistic regression. For all the mortality outcomes under study in relation to each 10% increase in weekly proportion of specimens positive for influenza A+B, never/seldom exercise (as reference) was associated with 5.8% to 8.5% excess risks (ER) of mortality (P<0.0001), while low/moderate exercise was associated with ER which were 4.2% to 6.4% lower than those of the reference (P<0.001 for all-natural causes; P = 0.001 for cardiovascular; and P = 0.07 for respiratory mortality). Frequent exercise was not different from the reference (change in ER −0.8% to 1.7%, P = 0.30 to 0.73).

Conclusion

When compared with never or seldom exercise, exercising at low to moderate frequency is beneficial with lower influenza-associated mortality.