455 research outputs found
Formulation and Evaluation of Matrix tablets of Ambroxol hydrochloride using Natural hydrophilic polymer
Se prepararon comprimidos matriciales de liberación prolongada de clorhidrato de ambroxol con diversas proporciones
de fármaco: polímero tales como F-1(1:1), F-2(1:1,5) y F-3 (1:2). Se utilizó goma xántica para la formación
de la matriz y celulosa microcristalina como diluyente. Se prepararon y evaluaron gránulos para determinar la
densidad aparente sin compactar, la densidad compactada, el índice de compresibilidad, el índice de Hausner y el
ángulo de reposo. Todos los gránulos se lubricaron y comprimieron con punzones planos de 9 mm. Los comprimidos
se evaluaron para determinar la uniformidad de peso, el contenido de principios activos, la friabilidad, la dureza y
la disolución in vitro. Todas las formulaciones se ajustaron a los estándares farmacopeicos. F-3 mostró una liberación
prolongada de fármaco durante 12 horas con una liberación del 97,3% y el perfi l de liberación fue similar al
de la muestra de clorhidrato de ambroxol comercial (A-MS). Además, se realizaron estudios de estabilidad según
la guía ICH. La liberación de fármaco sigue cinéticas de orden cero (0,9661) y se determinó que el mecanismo era
difusión combinada con erosión.Sustained release matrix tablets of ambroxol hydrochloride of different drug: polymer ratios, such as F-1(1:1), F-
2(1:1.5) and F-3 (1:2). Xanthan gum was used as matrix former and microcrystalline cellulose was used as diluent.
Granules were prepared and evaluated for loose bulk density, tapped density, compressibility index, hausners ratio and
angle of repose. All the granules were lubricated and compressed using 9mm fl at-faced punches. Compressed tablets
were evaluated for uniformity of weight, content of active ingredient, friability, hardness and In-vitro dissolution. All
the formulations showed compliance with Pharmacopoeial standards. F-3 showed the sustained release of drug for 12
hours with 97.3% release and the release profi le was close to the marketed sample of ambroxol hydrochloride (A-MS)
and Stability studies were performed as per ICH guide. The drug release follows zero order kinetics (0.9661) and the
mechanism was found to be diffusion coupled with erosion
A Qualitative Exploration of Sport and Social Pressures on Elite Athletes in Relation to Disordered Eating
Introduction: Athletes are at increased risk of disordered eating compared to non-athletes. Inspired by previous investigation into quantitative work on an etiological model of disordered eating in athletes, the current study aimed to explore a problematic aspect of the model: athletes' lived experiences of social and sport pressures in relation to the onset of disordered eating and differing eating behaviors. /
Methods: Nine (N = 9) male and female athletes representing a range of endurance sports took part in semi-structured interviews. Thematic analysis was utilized. /
Analysis: Analysis revealed two main themes each with two corresponding subthemes (1) Conflating physical appearance and sporting ability with the subthemes of (1a) social comparison in a sporting world and (1b) societal notions of “the athlete body” and (2) Living as an athlete with the corresponding subthemes of (2a) discipline and sacrifice and (2b) the balancing act. /
Discussion: It is the complex interaction between societal expectations as lived out in social messages and comparisons, and sport pressures that contributes to the development of disordered eating behaviors. These findings suggest that prevention and treatment of disordered eating in athletes can be applied from those already established in non-sporting realm
Vibrational and stochastic resonances in driven nonlinear systems:part two
Nonlinearity is ubiquitous in both natural and engineering systems. The resultant dynamics has emerged as a multidisciplinary field that has been very extensively investigated, due partly to the potential occurrence of nonlinear phenomena in all branches of sciences, engineering and medicine. Driving nonlinear systems with external excitations can yield a plethora of intriguing and important phenomena – one of the most prominent being that of resonance. In the presence of additional harmonic or stochastic excitation, two exotic forms of resonance can arise: vibrational resonance or stochastic resonance, respectively. Several promising state-of-the-art technologies that were not covered in Part One of this Theme Issue are discussed here. They include inter alia the improvement of image quality, the design of machines and devices that exert vibrations on materials, the harvesting of energy from various forms of ambient vibration, and control of aerodynamic instabilities. They form an important part of the Theme Issue as a whole, which is dedicated to an overview of vibrational and stochastic resonances in driven nonlinear systems. resonances in driven nonlinear systems
Impact of Splenic Artery Embolization on the Success Rate of Nonoperative Management for Blunt Splenic Injury
Introduction Nonoperative management (NOM) has become the treatment of choice for hemodynamically stable patients with blunt splenic injury. Results of outcome after NOM are predominantly based on large-volume studies from level 1 trauma centers in the United States. This study was designed to assess the results of NOM in a relatively low-volume Dutch level 1 trauma center. Methods An analysis of a prospective trauma registry was performed for a 6-year period before (period 1) and after the introduction and implementation of splenic artery embolization (SAE) (period 2). Primary outcome was the failure rate of initial treatment. Results A total of 151 patients were reviewed. An increased use of SAE and a reduction of splenic operations during the second period was observed. Compared with period 1, the failure rate after observation in period 2 decreased from 25% to 10%. The failure rate after SAE in period 2 was 18%. The splenic salvage rate (SSR) after observation increased from 79% in the first period to 100% in the second period. During the second period, all patients with failure after observation were successfully treated with SAE. The SSR after SAE in periods 1 and 2 was respectively 100% and 86%. Conclusions SAE of patients with blunt splenic injuries is associated with a reduction in splenic operations. The failure and splenic salvage rates in this current study were comparable with the results from large-volume studies of level 1 trauma centers. Nonoperative management also is feasible in a relatively low-volume level 1 trauma center outside the United State
Antimicrobial activity of a silver-microfibrillated cellulose biocomposite against susceptible and resistant bacteria
Genetic divergence is not the same as phenotypic divergence
Far too often, phenotypic divergence has been misinterpreted as genetic divergence, and based on phenotypic divergence, genetic divergence has been indicated. We have attempted to disprove this statement and call for the differentiation of phenotypic and genotypic variation
Centrality and transverse momentum dependence of elliptic flow of multi-strange hadrons and meson in Au+Au collisions at = 200 GeV
We present high precision measurements of elliptic flow near midrapidity
() for multi-strange hadrons and meson as a function of
centrality and transverse momentum in Au+Au collisions at center of mass energy
200 GeV. We observe that the transverse momentum dependence of
and is similar to that of and , respectively,
which may indicate that the heavier strange quark flows as strongly as the
lighter up and down quarks. This observation constitutes a clear piece of
evidence for the development of partonic collectivity in heavy-ion collisions
at the top RHIC energy. Number of constituent quark scaling is found to hold
within statistical uncertainty for both 0-30 and 30-80 collision
centrality. There is an indication of the breakdown of previously observed mass
ordering between and proton at low transverse momentum in the
0-30 centrality range, possibly indicating late hadronic interactions
affecting the proton .Comment: 7 pages and 4 figures, Accepted for publication in Physical Review
Letter
Azimuthal anisotropy in U+U and Au+Au collisions at RHIC
Collisions between prolate uranium nuclei are used to study how particle
production and azimuthal anisotropies depend on initial geometry in heavy-ion
collisions. We report the two- and four-particle cumulants, and
, for charged hadrons from U+U collisions at =
193 GeV and Au+Au collisions at = 200 GeV. Nearly fully
overlapping collisions are selected based on the amount of energy deposited by
spectators in the STAR Zero Degree Calorimeters (ZDCs). Within this sample, the
observed dependence of on multiplicity demonstrates that ZDC
information combined with multiplicity can preferentially select different
overlap configurations in U+U collisions. An initial-state model with gluon
saturation describes the slope of as a function of multiplicity in
central collisions better than one based on Glauber with a two-component
multiplicity model.Comment: Final paper version accepted for publication in Phys. Rev. Lett. New
version includes comparisons to a constituent quark glauber mode
Optimised laser microdissection of the human ocular surface epithelial regions for microarray studies
Background
The most important challenge of performing insitu transcriptional profiling of the human ocular surface epithelial regions is obtaining samples in sufficient amounts, without contamination from adjacent tissue, as the region of interest is microscopic and closely apposed to other tissues regions. We have effectively collected ocular surface (OS) epithelial tissue samples from the Limbal Epithelial Crypt (LEC), limbus, cornea and conjunctiva of post-mortem cadaver eyes with laser microdissection (LMD) technique for gene expression studies with spotted oligonucleotide microarrays and Gene 1.0 ST arrays.
Methods
Human donor eyes (4 pairs for spotted oligonucleotide microarrays, 3 pairs for Gene 1.0 ST arrays) consented for research were included in this study with due ethical approval of the Nottingham Research Ethics Committee. Eye retrieval was performed within 36 hours of post-mortem period. The dissected corneoscleral buttons were immersed in OCT media and frozen in liquid nitrogen and stored at −80°C till further use. Microscopic tissue sections of interest were taken on PALM slides and stained with Toluidine Blue for laser microdissection with PALM microbeam systems. Optimisation of the laser microdissection technique was crucial for efficient and cost effective sample collection.
Results
The starting concentration of RNA as stipulated by the protocol of microarray platforms was taken as the cut-off concentration of RNA samples in our studies. The area of LMD tissue processed for spotted oligonucleotide microarray study ranged from 86,253 μm2 in LEC to 392,887 μm2 in LEC stroma. The RNA concentration of the LMD samples ranged from 22 to 92 pg/μl. The recommended starting concentration of the RNA samples used for Gene 1.0 ST arrays was 6 ng/5 μl. To achieve the desired RNA concentration the area of ocular surface epithelial tissue sample processed for the Gene 1.0 ST array experiments was approximately 100,0000 μm2 to 130,0000 μm2. RNA concentration of these samples ranged from 10.88 ng/12 μl to 25.8 ng/12 μl, with the RNA integrity numbers (RIN) for these samples from 3.3 to 7.9. RNA samples with RIN values below 2, that had failed to amplify satisfactorily were discarded.
Conclusions
The optimised protocol for sample collection and laser microdissection improved the RNA yield of the insitu ocular surface epithelial regions for effective microarray studies on spotted oligonucleotide and affymetrix platforms
- …