Adaptive molecular evolution of virulence genes of avian influenza - A virus subtype H5N1: An analysis of host radiation

The phenomenon of host radiation is strongly influenced by the rates of mutation of their virulence genes. We have studied the molecular evolution of virulence genes (HA, NS, PB2) of the Avian Influenza Virus H5N1 from avian to human hosts. We used a site-specific comparison of synonymous (silent) and non-synonymous (amino acid altering) nucleotide substitutions for the three chosen genes in parasite populations from different hosts. Analyses were made using Maximum Likelihood (ML) genealogies for the null and alternate hypothesis based on differential gamma distribution rates. The null hypothesis had a higher rate of substitution and was found to be more suitable for all the studied genes by Likelihood Ratio Test (LRT). The study showed the NS gene to be having the fastest rate of evolution.     

Interspecific interactions of the critically endangered Forest Owlet (Athene blewitti)

The Forest Owlet (Athene blewitti) is critically endangered and at extremely high risk of extinction owing to its restricted distribution. An expedition was organized to determine the density of the Forest Owlet in the Melghat Tiger Reserve in February 2004 where they had been observed sporadically in the previous 5 years. We hoped to identify as many individuals as possible and to observe interspecific interactions in order to understand the social framework in which the species survives. A total of 43.4 km of jungle roads was checked; we confirmed the presence of three of the 13 previously reported individuals, and found 11 previously undetected owlets. Owlets were found in areas with several interconnected forest clearings which allowed the owlets to forage in them. In all cases where the Forest Owlet occurred, a village or agricultural fields of the indigenous people (Adivasis) was within a 0.5-km radius. It appears that Forest Owlets preferred to establish feeding territories in areas disturbed by anthropogenic activity such as clearing dead trees and undergrowth for fire, trampling undergrowth while searching for firewood, burning areas around the agricultural plots, or driving herds of cattle through the area. All of these activities appear to optimize the habitat for the sit-and-wait foraging Forest Owlet, facilitating detection and tracking of prey in open areas with sparse and short undergrowth, allowing a better all-round view due to a lower density of trees.     

Phosphoinositide 3-kinase signaling in the vertebrate retina

The phosphoinositide (PI) cycle, discovered over 50 years ago by Mabel and Lowell Hokin, describes a series of biochemical reactions that occur on the inner leaflet of the plasma membrane of cells in response to receptor activation by extracellular stimuli. Studies from our laboratory have shown that the retina and rod outer segments (ROSs) have active PI metabolism. Biochemical studies revealed that the ROSs contain the enzymes necessary for phosphorylation of phosphoinositides. We showed that light stimulates various components of the PI cycle in the vertebrate ROS, including diacylglycerol kinase, PI synthetase, phosphatidylinositol phosphate kinase, phospholipase C, and phosphoinositide 3-kinase (PI3K). This article describes recent studies on the PI3K-generated PI lipid second messengers in the control and regulation of PI-binding proteins in the vertebrate retina.     

Substituted spiro [2.3'] oxindolespiro [3.2″]-5,6-dimethoxy-indane-1″-one-pyrrolidine analogue as inhibitors of acetylcholinesterase

Series of pyrolidine analogues were synthesized and examined as acetylcholinesterase (AChE) inhibitors. Among the compounds, compounds 4k and 6k were the most potent inhibitors of the series. Compound 4k, showed potent inhibitory activity against acetyl cholinesterase enzyme with IC(50) 0.10 μmol/L. Pyrolidine analogues might be potential acetyl cholinesterase agents for AD.     

Practitioners of vipassana meditation exhibit enhanced slow wave sleep and REM sleep states across different age groups

Sleep and Biological Rhythms - Intense meditation practices influence brain functions in different ways and at different levels. Earlier studies have shown that meditation practices help to...     

Health status in COPD cannot be measured by the St George's Respiratory Questionnaire alone: an evaluation of the underlying concepts of this questionnaire

Background

The definition of "clinical asthma remission" is based on absence of symptoms and use of medication. However, in the majority of these subjects airway inflammation is still present when measured. In the present study we investigated whether "complete asthma remission", additionally defined by the absence of bronchial hyperresponsiveness (BHR) and the presence of a normal lung function, is associated with the absence of airway inflammation.

Methods

Patients with a former diagnosis of asthma and a positive histamine provocation test were re-examined to identify subjects with complete asthma remission (no asthma symptoms or medication, PC₂₀ histamine > 32 mg/ml, FEV₁ > 90% predicted). Patients with PC₂₀ histamine ≤ 32 mg/ml were defined as current asthmatics and were divided in two groups, i.e. asthmatics with and without BHR to adenosine 5'monophoshate (AMP). Sputum induction was performed 1 week before and 1 hour after AMP provocation. Sputum induction and AMP provocation were previously shown to be sensitive markers of airway inflammation.

Results

Seven patients met criteria for complete asthma remission. Twenty-three were current asthmatics, including twelve without hyperresponsiveness to AMP. Subjects with complete asthma remission showed no AMP-induced sputum eosinophilia (median (range) 0.2 (0 - 4.6)% at baseline and 0.2 (0 - 2.6)% after AMP). After AMP, current asthmatics had a significant increase in sputum eosinophils (0.5 (0 - 26.0)% at baseline and 2.6 (0 - 32.0) % after AMP), as had the subgroup of current asthmatics without hyperresponsiveness to AMP (0.2 (0 - 1.8)% at baseline and 1.3 (0 - 6.3)% after AMP).

Conclusions

Subjects with complete asthma remission, in contrast to subjects with current asthma, do not respond with eosinophilic inflammation in sputum after AMP provocations. These data lend support to the usefulness of the definition of complete asthma remission.     

Differential protein expression profiling by iTRAQ-2DLC-MS/MS of lung cancer cells undergoing epithelial-mesenchymal transition reveals a migratory/invasive phenotype

Transforming growth factor-beta (TGF-beta) induces epithelial-mesenchymal transition (EMT) of epithelial cells in both normal embryonic development and certain pathological contexts. Here, we show that TGF-beta induced-EMT in human lung cancer cells (A549; adenocarcinoma cells) mediates tumor cell migration and invasion phenotypes. To gain insights into molecular events during EMT, we employed a global stable isotope labeled profiling strategy using iTRAQ reagents, followed by 2DLC-MS/MS, which identified a total of 51 differentially expressed proteins during EMT; 29 proteins were up-regulated and 22 proteins were down-regulated. Down-regulated proteins were predominantly enzymes involved in regulating nutrient or drug metabolism. The majority of the TGF-beta-induced proteins (such as tropomyosins, filamin A, B, & C, integrin-beta1, heat shock protein27, transglutaminase2, cofilin, 14-3-3 zeta, ezrin-radixin-moesin) are involved in the regulation of cell migration, adhesion and invasion, suggesting the acquisition of a invasive phenotype.     

Gene selection algorithms for microarray data based on least squares support vector machine

Background  

In discriminant analysis of microarray data, usually a small number of samples are expressed by a large number of genes. It is not only difficult but also unnecessary to conduct the discriminant analysis with all the genes. Hence, gene selection is usually performed to select important genes.