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Lymphoma arises from cells of the immune system and trace metals augment the immune system and their imbalance may promote immunological disorders including tumorigenesis. The primary aim of the present investigation was to evaluate the levels of essential/toxic trace metals in the nails of non-Hodgkin and Hodgkin lymphomas patients in comparison with controls. The samples collected from patients and controls were digested in the mixture of HNO3-HClO4 and selected trace metals were analysed using flame atomic absorption spectrometry. The results showed that mean concentrations of some elements (Pb, Ni, Cd, Cu and Cr) in nails of non-Hodgkin lymphoma patients were significantly elevated (p < 0.05) than that of the controls whereas mean contents of Pb, Cu, Cd and Cr were observed to be significantly higher in the nails of Hodgkin lymphoma patients compared with healthy donors. Additionally, correlation study pointed out significantly diverse mutual associations of the trace metals among the patients and controls. The present results revealed noticeable disparities in the metal concentrations based on gender, food habits, tobacco use and types/stages of the donor's groups. Overall, the pathogenesis of disease significantly affected the trace metal balance in both patients' groups. [ABSTRACT FROM AUTHOR]

Cluster computing is receiving exponential popularity as a choice for high performance computing. This is mainly due to its effective cost performance ratio. Resource management systems (RMS) are the key component to manage the resources of clusters efficiently and have a very vital role in the performance of distributed parallel systems especially a job scheduling module. In this paper, we have empirically evaluated four resource management systems (SGE, TORQUE, and MAUI Scheduler and SLURM) with special focus on job scheduler component. These schedulers have been evaluated on a more comprehensive set of metrics such as throughput, CPU, memory and network utilization. Experiments were carried out on three different size testbeds with a range of scheduler configurations such as FCFS, Backfilling, Fair share and SJF scheduling techniques. A head-to-head comparison of different scheduling techniques has also been presented which highlights the effect of RMS on the performance of scheduling techniques. It has been observed from results that relative difference among the performance of scheduling techniques reached up to 63%. We conclude from the experiments that there is no single choice of RMS which can be identified as the best but SLURM performs better than others in most of the cases. [ABSTRACT FROM AUTHOR]

In this paper, we have proposed two backfill scheduling optimizations, i.e., Shortest Width First Backfill (SWFBF) and Shortest Area First Backfill (SAFBF). A near optimal simple, but effective job packing algorithm called the Select-Replace algorithm has also been presented to minimize external fragmentation. Proof of the concept has been given with the help of a simulation study. Five workloads which were derived from a clean version of the parallel workload archive (CTC, LANL, and SDSC. NASA) have been used to evaluate and compare proposed heuristics with previous techniques. With the simple but effective optimizations, significant (56.1%) performance improvement has been achieved as compared to EASY scheduler. [ABSTRACT FROM AUTHOR]

Abstract Purpose  To understand the mechanism of spherical microparticle formation during lyophilizing a tert-Butyl alcohol (TBA)/water solution of a zinc peptide adduct. Method  A small peptide, PC-1, as well as zinc PC-1 at (3:2) and (3:1) ratios, were dissolved in 44% (wt.%) of TBA/water, gradually frozen to −50°C over 2 h (“typical freezing step”), annealed at −20°C for 6 h (“annealing step”), and subsequently lyophilized with primary and secondary drying. Zinc peptide (3:1) lyophile was also prepared with quench cooling instead of the typical freezing step, or without the annealing step. Other TBA concentrations, i.e., 25%, 35%, 54% and 65%, were used to make the zinc peptide (3:1) adduct lyophile with the typical freezing and annealing steps. The obtained lyophile was analyzed by Scanning Electron Microscopy (SEM). The zinc peptide solutions in TBA/water were analyzed by Differential Scanning Calorimeter (DSC). The surface tension of the TBA/water co-solvent system was measured by a pendant drop shape method. Results  With typical freezing and annealing steps, the free peptide lyophile showed porous network-like structure that is commonly seen in lyophilized products. However, with increasing the zinc to peptide ratio, uniform particles were gradually evolved. Zinc peptide (3:1) adduct lyophiles obtained from 25%, 35% and 44% TBA exhibit a distinctive morphology of uniform and spherical microparticles with diameters of ∼3–4 μm, and the spherical zinc peptide particles are more predominant when the TBA level approaches 20%. Adopting quench cooling in the lyophilization cycle leads to irregular shape fine powders, and eliminating the annealing step causes rough particles surface. When TBA concentration increases above 54%, the lyophiles demonstrate primarily irregular shape particles. Conclusions  A proposed mechanism of spherical particle formation of the 3:1 zinc peptide encompasses the freezing of a TBA/water solution (20–70% TBA) causing the formation of a TBA hydrate phase (“dispersed TBA hydrate”). Decreasing the temperature further causes the formation of a eutectic mixture between TBA hydrate (“eutectic TBA hydrate”) and water. Due to its low aqueous solubility, the zinc peptide adduct accumulates in both of the dispersed and eutectic TBA hydrate phases to form a hydrophobic “oil” phase. Since the eutectic TBA hydrate phase is surrounded by ice, a “solid emulsion” forms to lower the interfacial energy, and gives rise to spherical zinc peptide particles upon solvent sublimation. Possibility of liquid–liquid phase separation during freeze-drying was also investigated, and no evidence was found to support this alternative mechanism. [ABSTRACT FROM AUTHOR]

Abstract Purpose  To understand the mechanism of nano-crystalline drug formation in Pluronic (i.e., poly(ethylene oxide-block-propylene oxide) triblock copolymers) based drug-polymer solid dispersions. Materials and Methods  Four polymers, Pluronic F127, F108, F68 and PEG 8000, which have different poly(ethylene oxide) (PEO) and poly(propylene oxide) (PPO) ratio and chain length, were co-spray dried with BMS-347070, a COX-2 inhibitor, to form 50/50 (w/w) drug-polymer solid dispersions. The solid dispersions were analyzed by powder X-ray diffraction (PXRD), modulated differential scanning calorimetry (mDSC), and hot-stage microscopy. Average size of drug crystallites in different polymers was calculated by the Scherrer equation based on peak-broadening effect in PXRD. Two other drug compounds, BMS-A and BMS-B, were also spray dried with Pluronic F127, and the solid dispersions were analyzed by PXRD and mDSC. Results  The average size of BMS-347070 crystallites in PEG 8000, F127, F108 and F68 polymers was 69, 80, 98 and 136 nm, respectively, and the degree of BMS-347070 crystallinity is the lowest in PEG 8000. Hot-stage microscopy showed that 50/50 drug-polymer dispersions crystallized in a two-step process: a portion of the polymer crystallizes first (Step 1), followed by crystallization of drug and remaining polymer (Step 2). The T g value of the BMS-347070/Pluronic dispersions after Step 1 (i.e., T g1) was measured and/or calculated to be 15–26C, and that of BMS-347070/PEG 8000 was 60C. Solid dispersions of BMS-A and BMS-B in Pluronic F127 have T g1 of 72 and 3C, respectively; and PXRD showed BMS-A remained amorphous after ∼3 weeks under ambient condition, while BMS-B crystallized in F127 with an average crystallite size of 143 nm. Conclusions  The size of drug crystallites in the drug-polymer solid dispersions is independent of polymer topology, but is caused kinetically by a combined effect of nucleation rate and crystal growth rate. When drug-Pluronic solid dispersions crystallize at room temperature, that is close to the T g1 of the systems, a fast nucleation rate and a relatively slow crystal growth rate of the drug synergistically produced small crystallite size. While the much higher T g1 value of drug-PEG 8000 led to a slower nucleation rate and an even slower crystal growth rate at room temperature, therefore, small crystallite size and low drug crystallinity were observed. Results from BMS-A/Pluronic and BMS-B/Pluronic systems confirmed this kinetic theory. [ABSTRACT FROM AUTHOR]

We investigated the effects of pressure overload hypertrophy on inward sodium (INa) and calcium currents (ICa) in single left ventricular myocytes to determine whether changes in these current systems could account for the observed prolongation of the action potential. Hypertrophy was induced by pressure overload caused by banding of the abdominal aorta. Whole-cell patch clamp experiments were used to measure tetrodotoxin (TTX)-sensitive inward currents. The main findings were that ICa density was unchanged whereas INa density after stepping from −80 to −30 mV was decreased by 30% (−9.0 ± 1.16 pA pF−1 in control and −6.31 ± 0.67 pA pF−1 in hypertrophy, p < 0.05, n= 6). Steady-state activation/inactivation variables of INa, determined by using double-pulse protocols, were similar in control and hypertrophied myocytes, whereas the time course of fast inactivation of INa was slowed (p < 0.05) in hypertrophied myocytes. In addition, action potential clamp experiments were carried out in the absence and presence of TTX under conditions where only Ca2+ was likely to enter the cell via TTX-sensitive channels. We show for the first time that a TTX-sensitive inward current was present during the plateau phase of the action potential in hypertrophied but not control myocytes. The observed decrease in INa density is likely to abbreviate rather than prolong the action potential. Delayed fast inactivation of Na+ channels was not sustained throughout the voltage pulse and may therefore merely counteract the effect of decreased INa density so that net Na+ influx remains unaltered. Changes in the fast INa do not therefore appear to contribute to lengthening of the action potential in this model of hypertrophy. However, the presence of a TTX-sensitive current during the plateau could potentially contribute to the prolongation of the action potential in hypertrophied cardiac muscle. (Mol Cell Biochem 261: 217–226, 2004) [ABSTRACT FROM AUTHOR]

Isolated left and right guinea pig atria were used as a bioassay for the detection of an endogenous cardioactive substance in bovine serum. Serum, buffer exchanged to Krebs–Henseleit solution, produced positive inotropic and chronotropic effects on the isolated guinea pig atria. The cardiotonic effects were unaffected by the combined presence of propranolol and methysergide (both 10−6M) and were also dissimilar in time course from other known cardiotons such as catecholamines and cardiac glycosides. Following ultrafiltration (using XM100A Amicon membranes), activity was found solely in the retentate fractions and was therefore probably due to a large molecular weight (>100 kDa) substance or a small molecule bound to a large protein. The cardioactive factor (CF) in the whole serum was heat labile, sensitive to acidification, exposure to potassium bromide and equilibration to physiological buffers of a low ionic strength. Isolation by conventional protein purification techniques was unsuccessful due to the labile nature of the active molecule(s) when exposed to non-physiological experimental conditions. Physical and biochemical properties of the CF which may help avoid inactivation are discussed for future experiments aimed at elucidating the nature and identity of the cardiotonic principle. (Mol Cell Biochem 261: 201–207, 2004) [ABSTRACT FROM AUTHOR]