A model analysis to measure the adherence of Etanercept and Fezakinumab therapy for the treatment of psoriasis

This article deals with a immunological model, which includes multiple classes of T cells, namely, the naive T cell, type I, type II and type 17 T helper cells (Th1, Th2, Th17), regulatory T cell (Treg) along with the activated natural killer cells (NK cells) and epidermal keratinocytes. In order to describe the etiology of psoriasis development, we have studied the basic mathematical properties of the model, existence and stability of the interior equilibrium. We have also derived the drug-induced mathematical model using impulse differential equation to determine the effects of combined biologics Etanercept (TNF-α inhibitor) and Fezakinumab (IL-22 monoclonal antibody) therapy considering perfect dosing during the inductive phase. We have determined the required dosing interval of both drugs to maintain the keratinocytes concentration below a threshold level. This study shows that Etanercept alone could theoretically maintain the keratinocytes level, whereas frequent dosing of Fezakinumab alone may not be enough to control the hyper-proliferation of keratinocytes. Furthermore, combination of the drugs with perfect dosing has the noticeable effect on keratinocytes dynamics, which may be suitable therapeutic approaches for treatment of psoriasis

Long term dynamics in a mathematical model of HIV-1 infection with delay in different variants of the basic drug therapy model

Infection with HIV-1, degrading the human immune system and recent advances of drug therapy to arrest HIV-1 infection, has generated considerable research interest in the area. Sebastian Bonhoeffer et al. [2], introduced a population model representing long term dynamics of HIV infection in response to available drug therapies. We consider a similar type of approximate model incorporating time delay in the process of infection on the healthy T cells which, in turn, implies inclusion of a similar delay in the process of viral replication. The model is studied both analytically and numerically. We also include a similar delay in the killing rate of infected CD4+ T cells by Cytotoxic TLymphocyte (CTL) and in the stimulation of CTL and analyze two resulting models numerically. The models with no time delay present have two equilibria: one where there is no infection and a non-trivial equilibrium where the infection can persist. If there is no time delay then the non-trivial equilibrium is locally asymptotically stable. Both our analytical results (for the first model) and our numerical results (for all three models) indicate that introduction of a time delay can destabilize the non-trivial equilibrium. The numerical results indicate that such destabilization occurs at realistic time delays and that there is a threshold time delay beneath which the equilibrium with infection present is locally asymptotically stable and above which this equilibrium is unstable and exhibits oscillatory solutions of increasing amplitude

Probiotic Lactococcus lactis: A Review

Lactococcus lactis plays a critical role in food, dairy and health sectors. In food and dairy industries, it is found in production processes of various fermented products such as sausages, pickled vegetables, beverages such as beer and wine, breads, soymilk kefir, sour milk, butter, cream, fresh cheese and different types of cheeses, like Cheddar, Colby, Cottage cheese, Camembert, cream cheese, Roquefort and Brie. Additionally, there is an increasing interest towards the possible health benefits of the probiotic activity of this organism which generally is species and strain specific and depends upon the survival in gastrointestinal tract with sufficient number. Certain strains have the ability to produce antimicrobial peptide called nisin which exhibits preservative potential. Therefore, application of bacteriocinogenic Lactococcus lactis in food and dairy sectors to preserve foods as a natural way and contributing health promoting attributes due to probiotic activity would definitely fulfil today’s consumer demands. This paper aimed to review the adaptation, antibiotic resistance, therapeutic and preservation potential of bacteriocinogenic and probiotic Lactococcus lactis

A mathematical model on CTL mediated control of hiv infection in a long-term drug therapy

Bonhoeffer et al.1 studied the long-term dynamics of HIV drug therapy and virus load dynamics. It is well known that highly active anti retroviral therapy (HAART) can effectively control the HIV replication. It is also well known that reverse transcriptase inhibitors (RTIs) could block new infection and as a result control HIV infection. The positive feedback control on such dynamics plays an important role and CD4+T cells are not only produced from a source but also produced from existing T cells. The present investigation takes into account these factors in the original model of Bonhoeffer et al. The optimal control therapy and the effect of time delay in the positive feedback control function have been investigated. Numerical simulation of the nonlinear model has confirmed our analytical studies.Read More: http://www.worldscientific.com/doi/abs/10.1142/S021833901350019

Excellent Electromagnetic Interference Shielding by Graphene- MnFe2O4-Multiwalled Carbon Nanotube Hybrids at Very Low Weight Percentage in Polymer Matrix

We report electromagnetic interference (EMI) shielding effectiveness of reduced graphene oxide-manganese ferrite (RGO-MnFe2O4) hybrids in presence of multiwalled carbon nanotubes (MWCNTs) as conductive filler in polyvinylidene fluoride (PVDF) matrix. MnFe2O4 nanoparticles and RGO-MnFe2O4 hybrids were synthesized by a facile one-step hydrothermal method and different PVDF/RGO-MnFe2O4 composite films containing fixed amount of MWCNTs (3 wt%) were fabricated by solution blending. The samples were characterized by X-ray diffraction, Raman spectroscopy, scanning electron and atomic force microscopies and by thermal gravimetric analysis. Excellent absorption and a total EMI shielding (SET) of ca. -38dB at 18 GHz were noted for 5wt% RGO-MnFe2O4. Interestingly, the storage modulus of this particular composite film showed 3 folds higher modulus as compared to control PVDF film. Our study establishes that simple and economical fabrication method of PVDF/RGO-MnFe2O4/MWCNTs composite film at very low filler content has a great potential as microwave absorbing material

Excellent Electromagnetic Interference Shielding by Graphene- MnFe2O4-Multiwalled Carbon Nanotube Hybrids at Very Low Weight Percentage in Polymer Matrix

We report electromagnetic interference (EMI) shielding effectiveness of reduced graphene oxide-manganese ferrite (RGO-MnFe2O4) hybrids in presence of multiwalled carbon nanotubes (MWCNTs) as conductive filler in polyvinylidene fluoride (PVDF) matrix. MnFe2O4 nanoparticles and RGO-MnFe2O4 hybrids were synthesized by a facile one-step hydrothermal method and different PVDF/RGO-MnFe2O4 composite films containing fixed amount of MWCNTs (3 wt%) were fabricated by solution blending. The samples were characterized by X-ray diffraction, Raman spectroscopy, scanning electron and atomic force microscopies and by thermal gravimetric analysis. Excellent absorption and a total EMI shielding (SET) of ca. -38dB at 18 GHz were noted for 5wt% RGO-MnFe2O4. Interestingly, the storage modulus of this particular composite film showed 3 folds higher modulus as compared to control PVDF film. Our study establishes that simple and economical fabrication method of PVDF/RGO-MnFe2O4/MWCNTs composite film at very low filler content has a great potential as microwave absorbing material

Temperature and Bias Dependent Trap Capture Cross Section in AlGaN/GaN HEMT on 6-in Silicon With Carbon-Doped Buffer

We report on the estimation of trap capture cross section in AlGaN/GaN HEMTs as a function of bias and temperature. Conductance dispersion technique was employed to study the AlGaN/GaN interface of the devices with a carbon-doped GaN buffer grown on 6-in silicon. While a negligible shift in the threshold voltage (VTH) was observed in temperature-dependent IDS-VGS sweeps, we observed a spread in the capacitance-voltage (C-V) measurements, indicating a contribution of interface traps. When biased near depletion, G/omega versus frequency plot for AlGaN/GaN interface exhibits two peaks which correspond to a pair of trap density (D-it) and trap time constant (T-it) values. This was explained using a circuit model in conjunction with energy band diagram. The D-it and T-it values for one peak were in the range from similar to 0.3-7 x 10(12)/eV.cm(2) and 0.6-10 mu s while for the other peak, D-it-T-it were in the range of similar to 0.1-35 x 10(12)/eV.cm(2) and similar to 0.06-0.3 mu s at 25 degrees C. From the T-it values, electron capture cross section (sigma) for both the traps was extracted and was found to be decreasing with increasing temperature in the range of 1.1 x 10(-20)-1 x 10(-19) cm(2) and 4.5 x 10(-20)-1 x 10(-17) cm(2) for slowtraps and fast traps, respectively. A multiphonon emission effect was invoked to explain the temperature dependence of capture cross section