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111.
The emergence of new strains of Influenza virus have caused several pandemics over the last hundred years with the latest being the H1N1 Swine flu pandemic of 2009. The Hemagglutinin (HA) protein of the Influenza virus is the primary target of human immune system and is responsible for generation of protective antibodies in humans. Mutations in this protein results in change in antigenic regions (antigenic drift) which consequently leads to loss of immunity in hosts even in vaccinated population (herd immunity). This necessitates periodic changes in the Influenza vaccine composition. In this paper, we investigate the molecular basis of the reported loss of herd immunity in vaccinated population (vaccine component: Influenza A/X-31/1968 (H3N2)) which resulted in the outbreak due to strain Influenza A/Port Chalmers/1/1973 (H3N2). Also, the effects of antigenic drift in HA protein (H3N2 vaccine strains 1968-2007) on the 3D structures as well as interactions with BH151, a 1968 antibody, has been studied. Rigid body molecular docking protocol has been used to study the antigen-antibody interactions. We believe that the present study will help in better understanding of host-pathogen interactions at the molecular level. 相似文献
112.
The non-coding fraction of the human genome, which is approximately 98%, is mainly constituted by repeats. Transpositions, expansions and deletions of these repeat elements contribute to a number of diseases. None of the available databases consolidates information on both tandem and interspersed repeats with the flexibility of FASTA based homology search with reference to disease genes. Repeats in diseases database (RiDs db) is a web accessible relational database, which aids analysis of repeats associated with Mendelian disorders. It is a repository of disease genes, which can be searched by FASTA program or by limitedor free- text keywords. Unlike other databases, RiDs db contains the sequences of these genes with access to corresponding information on both interspersed and tandem repeats contained within them, on a unified platform. Comparative analysis of novel or patient sequences with the reference sequences in RiDs db using FASTA search will indicate change in structure of repeats, if any, with a particular disorder. This database also provides links to orthologs in model organisms such as zebrafish, mouse and Drosophila. AVAILABILITY: The database is available for free at http://115.111.90.196/ridsdb/index.php. 相似文献
113.
Christopher J. van der Gast Paul Gosling Bela Tiwari Gary D. Bending 《Environmental microbiology》2011,13(1):241-249
Evidence suggests that microbial communities show patterns of spatial scaling which can be driven by geographical distance and environmental heterogeneity. Here we demonstrate that human management can have a major impact on microbial distribution patterns at both the local and landscape scale. Mycorrhizal fungi are vital components of terrestrial ecosystems, forming a mutualistic symbiosis with plant roots which has a major impact on above ground ecology and productivity. We used contrasting agricultural systems to investigate the spatial scaling of the most widespread mycorrhizal fungus group, the arbuscular mycorrhizal fungi (AMF). Using multiple sampling sites with a maximum separation of 250 km we describe for the first time the roles which land management, environmental heterogeneity and geographical distance play in determining spatial patterns of microbial distribution. Analysis of AMF taxa–area relationships at each sampling site revealed that AMF diversity and spatial turnover was greater under organic relative to conventional farm management. At the regional scale (250 km) distance–decay analyses showed that there was significant change in AMF community composition with distance, and that this was greater under organic relative to conventional management. Environmental heterogeneity was found to be the major factor determining turnover of AMF taxa at the landscape scale. Overall we demonstrate that human management can play a key role in determining the turnover of microbial communities at both the local and regional scales. 相似文献
114.
Active targeting of drug molecules can be achieved by effective attachment of suitable ligands to the surface of carriers.
The present work was attempted to prepare mannosylated gelatin microspheres (m-GMs) so as to achieve targeted delivery of
isoniazid (INH) to alveolar macrophages (AMs) and maintain its therapeutic concentration for prolonged period of time. Microspheres
were prepared by emulsification solvent extraction method and evaluated for physicochemical characteristics, drug release,
ex vivo drug uptake by AMs and pharmacokinetic characteristics. Fourier transform infrared spectroscopy and nuclear magnetic resonance
spectral analysis confirmed that mannosylation took place through Schiff base formation between aldehyde and amino groups
of mannose and gelatin, respectively. Prepared microspheres offered suitable physicochemical characteristics for their delivery
to AMs. Their average size was about 4 μm and drug entrapment efficiency of 56% was achieved with them. Ex vivo uptake results indicated that in comparison to plain microspheres, m-GMs were selectively uptaken and were found to be associated
with phago-lysosomal vesicles of AMs. Pharmacokinetic studies showed the formulation could maintain the therapeutic concentration
of INH for prolonged period of time even with a reduced clinical dose. m-GMs were found to be stable in broncheo-alveolar
lavage fluid. The study concluded that ligand decorated carriers could be a potential strategy to improve the therapeutic
properties of INH. 相似文献
115.
AbstractNuclear medicine techniques provide potential non-invasive tools for imaging infections and inflammations in the body in a precise way. These techniques are further exploited by the use of radiopharmaceuticals in conjunction with imaging tests such as scintigraphy and positron emission tomography. Improved agents for targeting infection exploit the specific accumulation of radiolabeled compounds to understand the pathophysiologic changes involved in the inflammatory process and correlate them with other chronic illnesses. In the recent past, a wide variety of radiopharmaceuticals have been developed, broadly classified as specific radiopharmaceuticals and nonspecific radiopharmaceuticals. New developments in positron emission (leveraging 18F and 18fluorodeoxyglucose) and heterocyclic/peptide chemistry and radiochemistry are resulting in unique agents with high specific activity. Various approaches to visualizing infection and inflammation are presented in this review, in an integral manner, that give a clear view of the existing radiopharmaceuticals in clinical practice and those under development. 相似文献
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117.
Jitendra Nath Tiwari Prashant Chaturvedi Nasreen Gazi Ansari Devendra Kumar Patel Sudhir Kumar Jain Ramesh Chandra Murthy 《Soil & Sediment Contamination》2011,20(3):315-328
Petroleum products are one of the major sources of energy for industry and daily life. Growth of the petroleum industry and shipping of petroleum products has resulted in the pollution. Populations living in the vicinity of oil refinery waste sites may be at greater risk of potential exposure to polycyclic aromatic hydrocarbons (PAH) through inhalation, ingestion, and direct contact with contaminated media. PAH have often been found to coexist with environmental pollutants including heavy metals due to similar pollution sources. The levels and distribution patterns of Σ16 PAH (sum of the 16 PAH) and heavy metals (lead, copper, nickel, cobalt, and chromium) were determined in soil and sediment in the vicinity (5 km radius) of an oil refinery in India. Concentrations of Σ16 PAH in the soils and sediments were found to be 60.36 and 241.23 ppm, respectively. Higher amount of PAH in sediments as compared to soil is due to low water solubility of PAH, settled in the bottom of aquatic bodies. The levels of lead, copper, nickel, cobalt, and chromium (total) in soil were 12.52, 13.52, 18.78, 4.84, and 8.29 ppm, while the concentrations of these metals in sediments were 16.38, 47.88, 50.15, 7.07, and 13.25 ppm, respectively. Molecular diagnostics indices of PAH (Ratio of Phenanthrene/Anthracene, Fluranthene/Pyrene) calculated for soil and sediment samples indicate that the oil refinery environment is contaminated with PAH from petrogenic as well as pyrolytic origin and heavy vehicular traffic on the Agra- Delhi National highway. Sixteen PAH priority pollutants were detected in the United States in entire samples collected near oil refinery areas and concentrations of Σ16 PAH in soil was found to be 1.20 times higher than the threshold value for PAH in soil by ICRCL (Inter-Departmental Committee on the Redevelopment of Contaminated Land). This concentration could lead to disastrous consequences for the biotic and abiotic components of the ecosystem and may affect the soil quality, thus impairing plant growth and its bioaccumulation in food chain. 相似文献
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120.
Qadri Q Sameer AS Shah ZA Hamid A Alam S Manzoor S Siddiqi MA 《Genetics and molecular research : GMR》2011,10(4):3038-3045
Glutathione-S-transferase P1 (GSTP1) is a critical enzyme of the phase II detoxification pathway. One of the common functional polymorphisms of GSTP1 is A→G at nucleotide 313, which results in an amino acid substitution (Ile105Val) at the substrate binding site of GSTP1 and reduces catalytic activity of GSTP1. To investigate the GSTP1 Ile105Val genotype frequency in prostate cancer cases in the Kashmiri population, we designed a case-control study, in which 50 prostate cancer cases and 45 benign prostate hyperplasia cases were studied for GSTP1 Ile105Val polymorphism, compared to 80 controls taken from the general population, employing the PCR-RFLP technique. We found the frequency of the three different genotypes of GSTP1 Ile105Val in our ethnic Kashmir population, i.e., Ile/Ile, Ile/Val and Val/Val, to be 52.4, 33.3 and 14.3% among prostate cancer cases, 48.5, 37.5 and 14% among benign prostate hyperplasia cases and 73.8, 21.3 and 5% in the control population, respectively. There was a significant association between the GSTP1 Ile/Val genotype and the advanced age group among the cases. We conclude that GSTP1 Ile/Val polymorphism is involved in the risk of prostate cancer development in our population. 相似文献