Ion-water clusters, bulk medium effects, and ion hydration

Thermochemistry of gas-phase ion-water clusters together with estimates of the hydration free energy of the clusters and the water ligands are used to calculate the hydration free energy of the ion. Often the hydration calculations use a continuum model of the solvent. The primitive quasichemical approximation to the quasichemical theory provides a transparent framework to anchor such efforts. Here we evaluate the approximations inherent in the primitive quasichemical approach and elucidate the different roles of the bulk medium. We find that the bulk medium can stabilize configurations of the cluster that are usually not observed in the gas phase, while also simultaneously lowering the excess chemical potential of the ion. This effect is more pronounced for soft ions. Since the coordination number that minimizes the excess chemical potential of the ion is identified as the optimal or most probable coordination number, for such soft ions, the optimum cluster size and the hydration thermodynamics obtained without account of the bulk medium on the ion-water clustering reaction can be different from those observed in simulations of the aqueous ion. The ideas presented in this work are expected to be relevant to experimental studies that translate thermochemistry of ion-water clusters to the thermodynamics of the hydrated ion and to evolving theoretical approaches that combine high-level calculations on clusters with coarse-grained models of the medium

Molecular packing and chemical association in liquid water simulated using ab initio hybrid Monte Carlo and different exchange-correlation functionals

In the free energy of hydration of a solute, the chemical contribution is given by the free energy required to expel water molecules from the coordination sphere and the packing contribution is given by the free energy required to create the solute-free coordination sphere (the observation volume) in bulk water. With the SPC/E water model as a reference, we examine the chemical and packing contributions in the free energy of water simulated using different electron density functionals. The density is fixed at a value corresponding to that for SPC/E water at a pressure of 1 bar. The chemical contribution shows that water simulated at 300 K with BLYP is somewhat more tightly bound than water simulated at 300 K with the revPBE functional or at 350 K with the BLYP and BLYP-D functionals. The packing contribution for various radii of the observation volume is studied. In the size range where the distribution of water molecules in the observation volume is expected to be Gaussian, the packing contribution is expected to scale with the volume of the observation sphere. Water simulated at 300 K with the revPBE and at 350 K with BLYP-D or BLYP conforms to this expectation, but the results suggest an earlier onset of system size effects in the BLYP 350 K and revPBE 300 K systems than that observed for either BLYP-D 350 K or SPC/E. The implication of this observation for constant pressure simulations is indicated. For water simulated at 300 K with BLYP, in the size range where Gaussian distribution of occupation is expected, we instead find non-Gaussian behavior, and the packing contribution scales with surface area of the observation volume, suggesting the presence of heterogeneities in the system

Study of difference in child rearing practice based on sex of child among married women of reproductive age group in urban slum of Mumbai

Background: India a vast country has left behind a number of stigmas and prejudices to move ahead as one nation. Still in a number of states, villages, cities and towns, gender bias is persistent leading to female discrimination. Objective: To study the difference in child rearing practices based on sex of child among married women of reproductive age group in urban slum of Mumbai.Methods:A community based, cross-sectional study was carried out among 900 married women of reproductive age group during a period of Jan. 2007 to Jan. 2008 at Shivajinagar urban health centre, which is field practice area of T. N. medical college, Mumbai. Participants were selected by systematic random sampling in an urban slum of Mumbai, Maharashtra.Results:In present study, a total of 900 married women with their children below five year are 1158 (male: 632 & female: 526) were analyzed. There was statistically significant difference between child rearing practices like breast feeding initiation, complimentary feeding, immunization status, nutritional status, and treatment seeking behavior.Conclusion:The findings in the present study confirm that sex based difference in child rearing practices persist in urban slum area of Mumbai.

Study of prevalence and socio-demographic determinants of pterygium patients attending at a tertiary care teaching hospital of Western Maharashtra, India

Background: The pterygium is known to cause refractive errors including astigmatism, which can have negative impact on the vision. The present study was carried out to find out the prevalence and socio-demographic determinants of pterygium patients attending Pravara rural hospital, Loni, Maharashtra, India.Methods: A cross-sectional study was conducted in outpatient department of ophthalmology in Pravara rural hospital, Loni. A total of 1910 patients of various ocular morbidities were registered during the studied period in the department of ophthalmology, among these, 100 patients who had pterygium were reviewed. All 100 patients were examined by torch and slit lamp. Data were analysed statistically using percentage and proportions whenever necessary.Results: Out of the 100 pterygium patients, 48% were in the age group of >60 years, followed by 32% in the age group of 51-60 years. In relation to occupation, maximum 82% patients were farm labours followed by 11% were house workers. Majority (62%) having unilateral, while (38%) was having bilateral pterygium. All cases of pterygium were nasal.Conclusion: People who work outdoors are subjected to increase U.V. exposure. So people must be aware of this and they must take appropriate precautions like wearing protective glasses and caps etc.

Biologics and biosimilars: role in modern pharmacotherapy and importance of pharmacovigilance

Biologics are highly sensitive large molecules with complex structure, difficult to characterize and reproduce, derived from living cells; used for treatment, diagnosis or prevention of disease. Examples are therapeutic hormones, vaccines, monoclonal antibodies etc. Biologicals are beneficial in the management of several health conditions which were once upon a time difficult to manage like cancer, multiple sclerosis, Alzheimer’s disease, rheumatoid arthritis, diabetes etc. Biosimilars are proteins that are similar to innovator biologics but not the same as they differ slightly in structure however with no clinically significant difference. Biosimilars are not the exact replicas of originator biologic and are therefore not generics. Biosimilars for their approval are not required to undergo intense clinical trials as innovator biologic but are required to produce data that demonstrates its similarity to an original biologic in terms of clinical efficacy and safety. However, manufactures of both the biologics and biosimilars are required to submit pharmacovigilance and risk management plans as part of their application. Marketing authorization for biosimilars was for the first time framed by EMA along with the guidelines for developing them. As biologics and biosimilars are derived proteins they have immunogenic potential and risk of adverse events which cautions their use. Pharmacovigilance is needed to ensure that adverse events are quickly detected, reported and attributed to the correct product and manufacturer. Regulations are implemented to improve identification and traceability of biologics. Automatic substitution should not be permitted for biologicals.

Thermodynamic Comparison and the Ideal Glass Transition of A Monatomic Systems Modeled as an Antiferromagnetic Ising Model on Husimi and Cubic Recursive Lattices of the Same Coordination Number

Two kinds of recursive lattices with the same coordination number but different unit cells (2-D square and 3-D cube) are constructed and the antiferromagnetic Ising model is solved exactly on them to study the stable and metastable states. The Ising model with multi-particle interactions is designed to represent a monatomic system or an alloy. Two solutions of the model exhibit the crystallization of liquid, and the ideal glass transition of supercooled liquid respectively. Based on the solutions, the thermodynamics on both lattices was examined. In particular, the free energy, energy, and entropy of the ideal glass, supercooled liquid, crystal, and liquid state of the model on each lattice were calculated and compared with each other. Interactions between particles farther away than the nearest neighbor distance are taken into consideration. The two lattices show comparable properties on the transition temperatures and the thermodynamic behaviors, which proves that both of them are practical to describe the regular 3-D case, while the different effects of the unit types are still obvious.Comment: 27 pages, 13 figure

Study of utilization of antimicrobial drugs and its resistance pattern in patients with septicemia at a tertiary care hospital

Background: Many types of bacteria can produce septicemia. The most common infections that lead to septicemia are urinary tract infections, pneumonia, nephritis and abdominal infections. Methods: The study aims to assess the pattern of antimicrobial drugs used in septicemia and to assess the etiological organisms and their drug sensitivity and resistance pattern. Study participants admitted to tertiary health care centre and who are having septicemia were included in this prospective observational study. Blood culture, bronchial secretions were subjected to microbiological analysis. The etiological organisms, their drug sensitivity and resistance pattern and the outcome of drug therapy were recorded. The clinical course of the study participants was monitored till cure either the resolution of pneumonia. Qualitative data were analyzed using the chi-square test or Fischer's exact test and quantitative data using the independent t test. Results: Mean duration of hospital stay in all patients 13.22±0.45 days and in resistance cases it was found 19.22±0.45 days. Mean duration of ICU stay in all patients was 4.34±0.45 days and in resistant cases mean duration of ICU stay was 8.18±0.45 days. Clinical outcome in overall admitted patients recovered was 97 patients (80.83%) death was 16 patients (13.33%). Clinical outcome in resistant patients recovered 16 patients (13.33%) and death 26 patients (21.66%). Conclusions: The organisms had a varied sensitivity and resistance pattern. The clinical outcome was multifactorial

A global view of T cell metabolism in systemic lupus erythematosus

Impaired metabolism is recognized as an important contributor to pathogenicity of T cells in Systemic Lupus Erythematosus (SLE). Over the last two decades, we have acquired significant knowledge about the signaling and transcriptomic programs related to metabolic rewiring in healthy and SLE T cells. However, our understanding of metabolic network activity derives largely from studying metabolic pathways in isolation. Here, we argue that enzymatic activities are necessarily coupled through mass and energy balance constraints with in-built network-wide dependencies and compensation mechanisms. Therefore, metabolic rewiring of T cells in SLE must be understood in the context of the entire network, including changes in metabolic demands such as shifts in biomass composition and cytokine secretion rates as well as changes in uptake/excretion rates of multiple nutrients and waste products. As a way forward, we suggest cell physiology experiments and integration of orthogonal metabolic measurements through computational modeling towards a comprehensive understanding of T cell metabolism in lupus