Mathematical Model on Magnetic Drug Targeting in Microvessel

Drug targeting is a process by which the distribution of drug in an organism is deployed in such a manner that its major fraction interacts exclusively with the target tissue at the cellular or subcellular level. Magnetic drug targeting is one of the major drug delivery methods due to its noninvasiveness, high targeting efficiency, and minimized toxic side effects on healthy cells and tissues. There are several experimental works on the magnetic drug targeting through microvessel, but very few works are carried out on the mathematical models on magnetic drug delivery. The aim of the present chapter is to discuss all major and minor factors, such as fluidic force, magnetic force, particle-particle interaction, inertia force, Saffman lift force, permeability of the microvessel and carrier particle, and so on, which influenced the drug targeting through microvessel by considering the nature of blood flow as Newtonian, non-Newtonian, single phase, and two phase model. A brief details of fluidic force, magnetic force, particle-particle interaction, Saffman force, buoyancy force, etc. Mathematical models on the fluidic force are discussed for Newtonian, non-Newtonian fluid, single phase, and two-phase fluid model including other forces that influence the magnetic drug targeting in microvessel

A model for magnetic drug targeting in a permeable microvessel with spherical porous carrier particles

We present a mathematical model for targeting a drug at malignant tissue cells in a permeable microvessel. The drug molecules are transported in carrier particles which are assumed to be porous spheres. This mode of drug delivery is non-invasive and has less toxic effects on healthy cells and tissues. The microvessel tube (see Figure 1) is subdivided into three regions, the outer endothelial glycocalyx layer where the blood has a Newtonian character, and a core and plug regions where the blood flow is described using a non-Newtonian Casson fluid model which is suitable for microvessels of radius 5mμ. Targeting is achieved through a locally applied magnetic field using a cylindrical magnet positioned outside the body near the tumour position so that the carrier particles, bound with nanoparticles and drug molecules are captured at the tumour site. The study seeks to understand, inter alia, the effects of the size and permeability of the carrier particle, the volume fraction of embedded magnetic nanoparticles and the placement of the external magnetic field on the magnetic targeting of the carrier particles

Chemically reacting and radiating nanofluid flow past an exponentially stretching sheet in a porous medium

The influence of non-uniform permeability, thermal radiation and variable chemical reaction on three-dimensional flow of an incompressible nanofluid over an exponentially-stretching sheet in association with a convective boundary condition has been investgated. In the present study, a new micro-convection model known as Patel model has been employed to enhance the thermal conductivity and hence the heat transfer capability of nanofluids. In the present analysis, base fluids such as water, 30% ethylene glycol, 50% ethylene glycol and nanoparticles such as Cu, Ag and Fe3O4 have been considered. With the help of some suitable transformations the governing partial differential equationsare converted into a set of ordinary differential equations which have beeen then solved numerically by using fourth-order Runge-Kutta method along with shooting technique. The influence of various embedded physical parameters have been explored through graphs for velocity, temperature, concentration, skin friction, local Nusselt and Sherwood numbers. The resistive force offered by the porous matrix belittles the momentum boundary layer and helps in growing the temperature and concentration boundary layers. Fluid temperature is an increasing function of radiation parameter Rd and Biot’s number Bi whereas concentration field is a decreasing function of Schmidt number Sc and chemical reaction parameter γ

Numerical Analysis Of The Bivariate Local Linearization Method (BLLM) For Partial Differential Equations In Casson Fluid Flow

Published ArticleThe double diffusion convection Casson fluid flow along a vertical plate incorporating Soret effect and viscous heating with thermal and solutal dispersion was studied. A well-known system of non-similar partial differential equations was solved using the bivariate local linearization method (BLLM). The solution procedure uses an approximation by a bivariate Lagrange interpolation polynomial. Older methods considered collocations along the non-dimensional boundary layer axis η only. In this paper collocations in both the (η, ζ) directions are considered. The numerical method is compared to the results obtained by the quasi-linearization method (QLM) and those previously published in the literature for the case (ζ = 0). This work also analyse the efficiency and robustness of the numerical method used as compared to traditional methods such as finite differences widely used in the literature. The increase in thermal stratification parameter decrease heat transfer coefficient and increase mass transfer coefficient. The increase in the non-Newtonian parameter result in the increase velocity profiles, skin friction coefficient and reduce both temperature and concentration profiles. Increasing the Biot number decrease temperature trends

“Register and Roll”: A Novel Initiative to Improve First Door-to-Balloon Time in ST Elevation Myocardial Infarction

Objective. We examined the cause of transfer delay in patients with an acute ST-segment myocardial infarction (STEMI) from non percutaneous coronary intervention (PCI) capable to PCI capable hospitals. We then implemented a novel, simple, and reliable initiative to improve the transfer process. Background. Guidelines established by the ACC/AHA call for door-to-balloon times of ≤90 minutes for patients with STEMI. When hospital transfer is necessary, this is only met in 8.6% of cases. Methods. All patients presenting with STEMI to a non-PCI capable hospital from April 2006 to February 2009 were analyzed retrospectively. After identifying causes of transfer delay the “Register and Roll” initiative was developed. An analysis of effect was conducted from March 2009 to July 2011. Results. 144 patients were included, 74 pre-initiative and 70 post- initiative. Time to EMS activation was a major delay in patient transfer. After implementation, the EMS activation time has significantly decreased and time to reperfusion approaches recommended goal (Median 114 min versus 90 min, ), with 55% in <90 minutes. Conclusion. “Register and Roll” streamlines the triage process and improves hospital transfer times. This initiative is easily instituted and reliable in a community hospital setting where resources are limited

A proposal for expansion of the medical specialty of rehabilitation medicine

The workforce of the medical specialty of Rehabilitation Medicine (RM) in the UK is 10 times less than the European average for the specialty of Physical and Rehabilitation Medicine (PRM). This can be explained partly by the difference in the scope of practice within the specialty between the UK and other European countries and USA. This opinion paper aims to compare the rehabilitation needs in chronic medical conditions and compare the scope of practice between countries within Europe and other regions of the world. The potential advantages of a broader remit specialty to improve rehabilitation care for patients by involving rehabilitation physicians in various medical conditions is explored. Recommendations have been put forward in the Rehabilitation Medicine Expansion Proposal (RMEP), which is likely to make the medical specialty of RM/ PRM more satisfying for the doctors working in the specialty and a more attractive career choice for those entering training in the specialty. There is a need for an international universal framework for the scope of the specialty to have a greater impact on improving the lives of those with chronic medical conditions

Electroosmosis modulated peristaltic biorheological flow through an asymmetric microchannel : mathematical model

A theoretical study is presented of peristaltic hydrodynamics of an aqueous electrolytic nonNewtonian Jeffrey bio-rheological fluid through an asymmetric microchannel under an applied axial electric field. An analytical approach is adopted to obtain the closed form solution for velocity, volumetric flow, pressure difference and stream function. The analysis is also restricted under the low Reynolds number assumption and lubrication theory approximations. Debye-Hückel linearization (i.e. wall zeta potential ≤ 25mV) is also considered. Streamline plots are also presented for the different electro-osmotic parameter, varying magnitudes of the electric field (both aiding and opposing cases) and for different values of the ratio of relaxation to retardation time parameter. Comparisons are also included between the Newtonian and general non-Newtonian Jeffrey fluid cases. The results presented here may be of fundamental interest towards designing lab-on-a-chip devices for flow mixing, cell manipulation, micro-scale pumps etc. Trapping is shown to be more sensitive to an electric field (aiding, opposing and neutral) rather than the electro-osmotic parameter and viscoelastic relaxation to retardation ratio parameter. The results may also help towards the design of organ-on-a-chip like devices for better drug design

Characterization of the Influenza A H5N1 Viruses of the 2008-09 Outbreaks in India Reveals a Third Introduction and Possible Endemicity

Widespread infection of highly pathogenic avian influenza A H5N1 was reported from backyard and commercial poultry in West Bengal (WB), an eastern state of India in early 2008. Infection gradually spread to Tripura, Assam and Sikkim, the northeastern states, with 70 outbreaks reported between January 2008 and May 2009. Whole genome sequence analysis of three isolates from WB, one isolate from Tripura along with the analysis of hemagglutinin (HA) and neuraminidase (NA) genes of 17 other isolates was performed during this study. In the HA gene phylogenetic tree, all the 2008-09 Indian isolates belonged to EMA3 sublineage of clade 2.2. The closest phylogenetic relationship was found to be with the 2007-09 isolates from Bangladesh and not with the earlier 2006 and 2007 Indian isolates implying a third introduction into the country. The receptor-binding pocket of HA1 of two isolates from WB showed S221P mutation, one of the markers predicted to be associated with human receptor specificity. Two substitutions E119A (2 isolates of WB) and N294S (2 other isolates of WB) known to confer resistance to NA inhibitors were observed in the active site of neuraminidase. Several additional mutations were observed within the 2008-09 Indian isolates indicating genetic diversification. Overall, the study is indicative of a possible endemicity in the eastern and northeastern parts of the country, demanding active surveillance specifically in view of the critical mutations that have been observed in the influenza A H5N1 viruses