Non-Directional Conjugation of Fluorescent Antibodies to Gold Nanoparticles for Stem Cell Therapy

The objective of this study was to design citrate-coated gold nanoparticles conjugated with FITC-IgG, a fluorescent antibody, and to qualitatively and quantitatively measure the resulting fluorescent emission. Optical properties of the gold nanoparticles were measured at various stages to provide evidence of successful conjugation. The absorbance spectrum of the citrate gold nanoparticles was compared to that of the reaction mixture containing the gold nanoparticles and the FITC-IgG. A noticeable broadening of the absorption peak was observed at 519 nm indicating a surface modification of the gold nanoparticles. Fluorescence data was obtained with a fluorospectrometer and revealed a significant amount of fluorescent quenching in the reaction mixture as well as the washed mixture containing only fully conjugated molecules. However, the conjugated nanoparticles still emitted fluorescence at 519 nm as shown by the images captured under confocal microscopy. Based on the obtained optical densities of the reaction mixture and the FITC-IgG, the mass of molecules that were conjugated to the nanoparticles was calculated and determined to be approximately 24 FITC-IgG molecules per gold nanoparticle

MANUFACTURING TECHNIQUES FOR TITANIUM ALUMINIDE BASED ALLOYS AND METAL MATRIX COMPOSITES

Dual phase titanium aluminides composed vastly of gamma phase (TiAl) with moderate amounts of alpha2 phase (Ti3Al) have been considered for several high temperature aerospace and automobile applications. High specific strength coupled with exceptional high temperature performance in the areas of creep and oxidation resistance makes titanium aluminides "materials of choice" for next generation propulsion systems. Titanium aluminides are primarily being considered as potential replacements for Ni-based superalloys in gas turbine engine components with the aim of developing more efficient and leaner engines with high thrust-to-weight ratio. As titanium aluminides lack room temperature ductility, traditional manufacturing techniques such as casting, forging and rolling are more expensive to perform. To overcome this, research over the past decade has examined powder metallurgy techniques such as hot-isostatic pressing, sintering and hot-pressing to produce titanium aluminides parts. Enhancements in these powder metallurgy techniques has produced near-net shape parts of titanium aluminides possessing a homogeneous and refined microstructure and thereby exhibiting better mechanical performance. This study presents a novel powder metallurgy approach to consolidate titanium aluminide powders. Traditional powder consolidation processes require exposure to high temperatures over a lengthy duration. This exposure leads to grain growth in the consolidated part which adversely affects its mechanical properties. A rapid consolidation process called Plasma Pressure Compaction (P2C) has been introduced and utilized to consolidate titanium aluminide powders to produce titanium aluminide parts with minimal grain growth. The research also explores the role of small alloying additions of Nb and Cr to enhance ductility of the consolidated parts. The grain size of the consolidated parts is further reduced in the sub-micrometer range by milling the as-received powders. Finally, a metal matrix composite with TiAl matrix reinforced with TiB was developed by first blending the matrix and the reinforcement powders and then consolidating the powder blend

DESIGN AND EVALUATION OF CONTROLLED-RELEASE OCULAR INSERTS OF BRIMONIDINE-TARTRATE AND TIMOLOL MALEATE

Objective: The current work was attempted to formulate and evaluate a controlled-release matrix-type ocular inserts containing a combination of brimonidine tartrate and timolol maleate, with a view to sustain the drug release in the cul-de-sac of the eye.Methods: Initially, the infrared studies were done to determine the drug–polymer interactions. Sodium alginate-loaded ocuserts were prepared by solvent casting technique. Varying the concentrations of polymer—sodium alginate, plasticizer—glycerine, and cross-linking agent—calcium chloride by keeping the drug concentration constant, made a total of nine formulations. These formulations were evaluated for its appearance, drug content, weight uniformity, thickness uniformity, percentage moisture loss, percentage moisture absorption, and in vitro release profile of the ocuserts. Finally, accelerated stability studies and the release kinetics were performed on the optimised formulation.Results: It was perceived that polymer, plasticizer, and calcium chloride had a significant influence on the drug release. The data obtained from the formulations showed that formulation—F9 was the optimised formulation, which exhibited better drug release. The release data of the optimised formulation tested on the kinetic models revealed that it exhibited first-order release kinetics. Conclusion: It can be concluded that a natural bioadhesive hydrophilic polymer such as sodium alginate can be used as a film former to load water soluble and hydrophilic drugs like brimonidine tartrate and timolol maleate. Among all formulations, F9 with 400 mg sodium alginate, 2% calcium chloride and 60 mg glycerin were found to be the most suitable insert in terms of appearance, ease of handling, thickness, in vitro drug release and stability

Anion-induced increases in the affinity of colcemid binding to tubulin

Colcemid binds tubulin rapidly and reversibly in contrast to colchicine which binds tubulin relatively slowly and essentially irreversibly. At 37° C the association rate constant for colcemid binding is 1.88 × 106 M-1 h-1, about 10 times higher than that for colchicine; this is reflected in the activation energies for binding which are 51.4 kJ/mol for colcemid and 84.8 kJ/mol for colchicine. Scatchard analysis indicates two binding sites on tubulin having different affinities for colcemid. The high-affinity site (Ka= 0.7 × 105 M-1 at 37° C) is sensitive to temperature and binds both colchicine and colcemid and hence they are mutually competitive inhibitors. The low-affinity site (Kb= 1.2 × 104 M-1) is rather insensitive to temperature and binds only colcemid. Like colchicine, 0.6 mol of colcemid are bound/mol of tubulin dimer (at the high-affinity site) and the reaction is entropy driven (163 J K-1 mol-1). Similar to colchicine, colcemid binding to tubulin is stimulated by certain anions (viz. sulfate and tartrate) but by a different mechanism. Colcemid binding affinity at the lower-affinity site of tubulin is increased in the presence of ammonium sulfate. Interestingly, the lower-affinity site on tubulin for colcemid, even when converted to higher affinity in presence of ammonium sulfate, is not recognized by colchicine. We conclude that tubulin possesses two binding sites, one of which specifically recognized the groups present on the B-ring of colchicine molecule and is effected by the ammonium sulfate, whereas the higher-affinity site, which could accommodate both colchicine and colcemid, possibly recognized the A and C ring of colchicine

Involvement of Src family of kinases and cAMP phosphodiesterase in the luteinizing hormone/chorionic gonadotropin receptor-mediated signaling in the corpus luteum of monkey

Background: In higher primates, during non-pregnant cycles, it is indisputable that circulating LH is essential for maintenance of corpus luteum (CL) function. On the other hand, during pregnancy, CL function gets rescued by the LH analogue, chorionic gonadotropin (CG). The molecular mechanisms involved in the control of luteal function during spontaneous luteolysis and rescue processes are not completely understood. Emerging evidence suggests that LH/CGR activation triggers proliferation and transformation of target cells by various signaling molecules as evident from studies demonstrating participation of Src family of tyrosine kinases (SFKs) and MAP kinases in hCG-mediated actions in Leydig cells. Since circulating LH concentration does not vary during luteal regression, it was hypothesized that decreased responsiveness of luteal cells to LH might occur due to changes in LH/CGR expression dynamics, modulation of SFKs or interference with steroid biosynthesis. Methods: Since, maintenance of structure and function of CL is dependent on the presence of functional LH/CGR its expression dynamics as well as mRNA and protein expressions of SFKs were determined throughout the luteal phase. Employing well characterized luteolysis and CL rescue animal models, activities of SFKs, cAMP phosphodiesterase (cAMP-PDE) and expression of SR-B1 (a membrane receptor associated with trafficking of cholesterol ester) were examined. Also, studies were carried out to investigate the mechanisms responsible for decline in progesterone biosynthesis in CL during the latter part of the non-pregnant cycle. Results and discussion: The decreased responsiveness of CL to LH during late luteal phase could not be accounted for by changes in LH/CGR mRNA levels, its transcript variants or protein. Results obtained employing model systems depicting different functional states of CL revealed increased activity of SFKs pSrc (Y-416)] and PDE as well as decreased expression of SR-B1correlating with initiation of spontaneous luteolysis. However, CG, by virtue of its heroic efforts, perhaps by inhibition of SFKs and PDE activation, prevents CL from undergoing regression during pregnancy. Conclusions: The results indicated participation of activated Src and increased activity of cAMP-PDE in the control of luteal function in vivo. That the exogenous hCG treatment caused decreased activation of Src and cAMP-PDE activity with increased circulating progesterone might explain the transient CL rescue that occurs during early pregnancy

Integration of Microfluidic Devices and Smart Phones for Water Monitoring –A Review

Microfluidic innovation permits analytical system to be scaled down and incorporated into lab-on-a-chip devices, minimizing the volume of reagents consumed and of waste created, and permitting the utilization of low-fueled pumping system. Here, in this survey we will ponder the microfluidic sensors able to do quick, multiplexed detection. Electrochemical detection in a microfluidic stage offers numerous focal points, for example, compactness, insignificant utilization of instrumentation, and simple integration with electronics. In numerous parts of the world, be that as it may, the required gear for detection through electrochemical sensors is either not available or inadequately compact, and administrators may not be prepared to utilize these sensors and translate results, at last keeping its wide adoption. Presently a days, step by step the versatile innovation is growing quick. Joining these sort of versatile electrochemical procedures with such quickly developing advances will give advantage to the community. Toward a solution to water quality interventions, individuals have effectively demonstrate a microfluidic electrochemical sensor joined with a portable interface that identifies the different water contaminants and contaminations, appropriate for quick, reasonable, and point-of-care water monitoring. In this survey, we will first give the general foundation of microfluidic-based detection, versatile innovations available in combination with microfluidic sensors, and their integration

MLA for Identifying Disease-Treatment

The Machine Learning is pictured as a tool by which computer-based systems can be unified in the healthcare field in order to get a better, more efficient medical care. This paper describes a Machine Learning based methodology for building an application and scattering healthcare information. It extracts sentences from published medical papers that mention diseases and treatments, and identifies relation between meanings that exist between diseases and treatment