Background: Self-managementinterventionsimprovevarious outcomes for many chronic diseases. The definite place of self-management in the care of chronic obstructive pulmonary disease (COPD) has not been established. We evaluated the effect of a continuum of self-management, specific to COPD, on the use of hospital services and health status among patients with moderate to severe disease.

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Superparamagnetism has been widely used for many biomedical applications, such as early detection of inflammatory cancer and diabetes, magnetic resonance imaging (MRI), hyperthermia, etc., whereas incorporation of superparamagnetism in stimulus-responsive hydrogels has now gained substantial interest and attention for application in these fields. Recently, pH-responsive superparamagnetic hydrogels showing the potential use in disease diagnosis, biosensors, polymeric drug carriers, and implantable devices, have been developed based on the fact that pH is an important environmental factor in the body and some disease states manifest themselves by a change in the pH value. However, improvement in pH sensitivity of magnetic hydrogels is a dire need for their practical applications. In this study, we report the distinctly high pH sensitivity of new synthesized dual-responsive magnetic hydrogel nanocomposites, which was accomplished by copolymerization (free-radical polymerization) of two pH-sensitive monomers, acrylic acid (AA) and vinylsulfonic acid (VSA) with an optimum ratio, in the presence of presynthesized superparamagnetic iron oxide nanoparticles (Fe 3 O 4 (OH) x ). The monomers contain pH-sensitive functional groups (COO – and SO 3 – for AA and VSA, respectively), and they have also been widely used as biomaterials because of the good biocompatibility. The pH sensitivity of the superparamagnetic hydrogel, poly(acrylic acid- co -vinylsulfonic acid), PAAVSA/Fe 3 O 4 , was investigated by swelling studies at different pH values from pH 7 to 1.4. Distinct pH reversibility of the system was also demonstrated through swelling/deswelling analysis. Thermal stability, chemical configuration, magnetic response, and structural properties of the system have been explored by suitable characterization techniques. Furthermore, the study reveals a pH-responsive significant change in the overall morphology and packing fraction of iron oxide nanoparticles in PAAVSA/Fe 3 O 4 via energy-dispersive X-ray (EDX) elemental mapping with the field emission scanning electron microscopy (FESEM) study (for freeze-dried PAAVSA/Fe 3 O 4 , swelled at different pH values), implying a drastic change in susceptibility and induced saturation magnetization of the system. These important features could be easily utilized for the purpose of diagnosis using magnetic probe and/or impedance analysis techniques.

Clinical resistance to pentavalent antimonial drugs in the form of sodium antimony gluconate (SAG) has become a major problem in the treatment of kala azar (visceral leishmaniasis) in India. The mechanism of resistance is unclear in these clinical isolates, although work has been conducted with Leishmania species mutants selected in vitro by stepwise increase of drug concentration, using antimony-related metal arsenic and, more recently, SAG. In the present study, we investigated the molecular aspect of drug resistance in clinically confirmed SAG-resistant field isolates. Our results show that the mechanisms of resistance postulated for laboratory mutants of Leishmania species are not operating in field isolates of Leishmania donovani. Instead, we identified a novel gene amplified in these drug-resistant parasites whose locus is on chromosome 9. The significant finding was that this isolated fragment confers antimony resistance to wild-type Leishmania species after transfection. We speculate that protein phosphorylation may play a role in signal transduction pathway in the parasite after exposure to drug-conferring resistance.

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Androgens drive male secondary sexual differentiation and maturation. Mutations in the androgen receptor (AR) gene cause a broad spectrum of abnormal phenotypes in humans, ranging from mild through partial to complete androgen insensitivity. We have analyzed the AR gene by using denaturing high-performance liquid chromatography (DHPLC) and direct sequencing and have studied gonads histologically in a familial case of complete androgen insensitivity syndrome. Sequence analysis of the AR gene showed a novel C2578T missense mutation, resulting in the replacement of a highly conserved leucine residue with phenylalanine (L859F) in ligand-binding domain of the receptor. The residue L859, located in helix 10 of the androgen receptor, plays a significant role in overall architecture of ligand-binding pocket. The mutation was absent from the father, normal brother of the patients, and 100 normal males recruited in this study as controls. The inheritance of the mutation in the family clearly shows that C2578T is the underlying mutation for the eventual phenotype in the patients. Histology of patient's gonads showed Leydig cell hyperplasia, with a few or no spermatogonium. It is thought that AR gene mutations result in hormonal imbalance, resulting in the high levels of luteinizing hormone (LH) and ultimately Leydig cell hyperplasia or tumor formation. In the present study, we have reported a rare familial case of Leydig cell hyperplasia despite consistently normal LH levels. The finding will help in giving counseling to this family and prevent the transmission of the mutated X chromosome to the coming generations.

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