Role of nephrotoxic drugs in contrast-induced nephropathy

Background: Elevation of serum creatinine (SCr) more than 0.5 mg/dl or 25% or more of the baseline value in 3 days after contrast administration is considered as contrast-induced nephropathy (CIN). Contrast material (CM) used in the radiological studies like contrast-enhanced computed tomography (CECT) and intravenous urogram (IVU) are nephrotoxic and their ability to cause renal damage is increased when other potential nephrotoxic drugs are given simultaneously. The present study aimed to demonstrate the effects of CM on patients who are on nephrotoxic drugs by studying the incidence of CIN in patients who are on nephrotoxic drugs and need a CECT or IVU (cases presenting with an emergency). The study compares the incidence of CIN in patients on nephrotoxic drugs with that in those not on nephrotoxic drugs and evaluates the importance of withdrawal of nephrotoxic drugs (3 days) in non-emergency contrast studies.Methods: The study population is divided into three groups. Group A consists of 40 cases undergoing emergency CECT or IVU, who are on nephrotoxic drugs. 40 cases undergoing CECT or IVU after 3 days of holding of nephrotoxic drugs are included in Group B. Group C consists of 40 cases undergoing CECT or IVU who are not on any nephrotoxic drugs. Patients with parenchymal renal disease, renal injury, and renal mass are excluded from the study. All cases having SCr <1.4 mg/dl are included in the study. SCr investigation is repeated 3 days after the contrast study.Results: The incidence of CIN is more in the patients who are on nephrotoxic drugs (15%) than in those who are not on nephrotoxic drugs (5%). There is no significant difference in the incidence of CIN between Groups B and C. p=0.045 between Groups A and B was noted showing the significance of waiting period in reducing the incidence of CIN.Conclusions: The incidence of CIN is more in patients who underwent contrast studies without stopping nephrotoxic drugs and stoppage of nephrotoxic drugs for 3 days prior to the procedure is beneficial by reducing the incidence of CIN among them

Health Technology Use in Noncommunicable Disorders: Challenges and Opportunities in India

Health care in India is undergoing a rapid change from its historical focus on acute disease management to a focus more on chronic and continuous care-based model for non-communicable disorders. Health technology could be a game changer as it has a potential to optimize costs and effectively manage such operations. IT solutions are likely to become an integral part of process management, patient care and the hospital management information system in future. This brief communication describes the key enablers and limitations of using health technology in chronic diseases in developing countries like India

Health Technology Use in Noncommunicable Disorders: Challenges and Opportunities in India

Health care in India is undergoing a rapid change from its historical focus on acute disease management to a focus more on chronic and continuous care-based model for noncommunicable disorders. Health technology could be a game changer as it has a potential to optimize costs and effectively manage such operations. IT solutions are likely to become an integral part of process management, patient care and the hospital management information system in future. This brief communication describes the key enablers and limitations of using health technology in chronic diseases in developing countries like India

Processing-Structure-Microstructure-Property Relationships in Polymer Nanocomposites

The optimal development of polymer nanocomposites using carbon nanotube (CNTs) and carbon nanofiber (CNFs) fillers requires a complete understanding of processing-structure-property relationships. The purpose of this understanding is to determine the optimal approach for processing polymer nanocomposites with engineered microstructures and enhanced material properties. In this research, two processing techniques were investigated: solvent processing and twin screw extrusion. The former is a batch process which employs mixing a polymer solution with a filler suspension using long mixing times and low levels of shear mixing. The latter is a continuous process that mixes polymer melts with solid nanoscale ingredients using high levels of shear mixing for a short mixing time. Previous studies conducted on polymer-CNT/CNF using these processes have focused mainly on processing-microstructure and structure-property relationships using one technique or the other. This research focuses on understanding the processing-property relationships by comparing the structure-property relationships resulting from the two processes. Furthermore, the effect of ingredients and processing parameters within each process on microstructure and structure-property relationships was investigated. The microstructural features, namely, distribution of agglomerates, dispersion, alignment, and aspect ratio of the filler were studied using optical, scanning electron, confocal and transmission electron microscopy, respectively. The composition of the filler was determined using thermogravimetric analysis. The electrical, rheological, thermo-oxidative and mechanical properties of the composites were also investigated. Many significant insights related to processing-structure-property relationships were obtained including: (a) deagglomeration is a critical combination of the magnitude of shear rate and the residence time, (b) the structure-property relationships can be modeled using a new methodology based on the degree of percolation by representing the material as an interpenetrating phase composite, (c) annealing can re-establish interconnectivity and improve electrical properties, (d) the degree of dispersion can be resolved using thermogravimetric analysis, and (e) increasing extrusion speed inhibits thermal decomposition and begins to asymptotically increase strength and stiffness through reduction in aspect ratio and size of agglomerates. Finally, a new combinatorial approach was developed for rapidly determining processing-structure relationships of polymer nanocomposites. This dissertation has broad implications in the processing of high performance and multifunctional polymer nanocomposites, combinatorial materials science, and histopathology

ACTIVITY OF POLYHERBAL EXTRACT AGAINST BACTERIA CAUSING SKIN INFECTIONS IN DIABETIC PATIENTS.

Objective   : - The objective of   this   study is to evaluate antibacterial activity of Polyherbal extract on few    microorganisms causing skin infections in most of the  diabetic patients  .Methods   : - Methanolic Polyherbal extract was prepared  from Acacia ferruginia (bark &amp; fruit), Chloroxylon swietenia (bark, leaf, root), Casearia elliptica (bark), Terminalia alata (root, leaf). The preliminary phytochemical analysis was performed to identify the major phytoconstituents  in the extract.  Polyherbal extract was evaluated for antibacterial activity against bacteria   like Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa,   Escherichia coli, Proteus species, Klebsiella species causing skin infections , diabetic foot infections in diabetic patients. In-vitro method of agar diffusion disc method was used for the evaluation of antibacterial activity through zone of inhibition.  The standard drug used was Gentamicin. Minimum Inhibitory Concentration (MIC) of the extract was done  using broth dilution method.Results:  The polyherbal extract showed good antibacterial activity. The standard drug used was Gentamicin.  The Methanolic   Polyherbal extract showed   potent activityon all the selected microorganisms. The Polyherbal extract was active  against Pseudomonas aeruginosa (2.57 +  0.39) and E.coli (2.92 + 0.29) when compared with standard. The polyherbal extract showed potent activity  on Bacillus subtilis and  Proteus vulgaris.Conclusion : The polyherbal extract showed broad spectrum activity by being active against gram positive and gram negative microorganisms providing the scope for further analysis as a antibacterial preparation for the skin infections in diabetes patients. Â

Modelling and Control of Doubly Fed Induction Generator Based Stand-Alone Wind Energy Conversion System

The application of wound rotor induction machine is widely spread in wind energy generating stations because of its adaptability for variable speed wind turbines through which maximum possible extraction of wind energy is possible. Also among all the induction generator configurations for wind power systems the use of Doubly Fed Induction Generator (DFIG) configuration with back to back pulse width modulated voltage source converters (VSC) is one of the best topologies available and it is suitable for both grid connected systems as well as stand-alone systems. Here only stand-alone application of DFIG is considered. In this thesis mathematical modelling of doubly fed induction machine is presented. The control strategies for both stator side converter and rotor side converter are developed in stator flux oriented reference frame. The dynamics of dc link voltage build-up phase is also included. The stator side converter is used to control the output voltage in direct voltage control manner and the rotor side converter is current controlled where the power imbalance of the system is nullified using dc link voltage controller which modifies the quadrature axis rotor current reference value according to the changes in the wind speed as well as the load. Two control algorithms are presented out of which one gives the best performance for all kinds of loads (balance, unbalance, linear and non-linear) and the other gives poor load regulation and unwanted distortions in the output voltage for non-linear and unbalanced load