Levels of major selenoproteins in T cells decrease during HIV infection and low molecular mass selenium compounds increase

It has been observed previously that plasma selenium and glutathione levels are subnormal in HIV-infected individuals, and plasma glutathione peroxidase activity is decreased. Under these conditions the survival rate of AIDS patients is reduced significantly. In the present study, using 75Se-labeled human Jurkat T cells, we show that the levels of four 75Se-containing proteins are lower in HIV-infected cell populations than in uninfected cells. These major selenoproteins migrated as 57-, 26-, 21-, and 15-kDa species on SDS/PAGE gels. In our earlier studies, the 57-kDa protein was purified from T cells and identified as a subunit of thioredoxin reductase. The 26- and 21-kDa proteins were identified in immunoblot assays as the glutathione peroxidase (cGPX or GPX1) subunit and phospholipid hydroperoxide glutathione peroxidase (PHGPX or GPX4), respectively. We recently purified the 15-kDa protein and characterized it as a selenoprotein of unknown function. In contrast to selenoproteins, low molecular mass [75Se]compounds accumulated during HIV infection and migrated as a diffuse band near the front of SDS/PAGE gels.     

HIRA, a DiGeorge syndrome candidate gene, is required for cardiac outflow tract septation

DiGeorge syndrome (DGS) is a congenital disease characterized by defects in organs and tissues that depend on contributions by cell populations derived from neural crest for proper development. A number of candidate genes that lie within the q11 region of chromosome 22 commonly deleted in DGS patients have been identified. Orthologues of the DGS candidate gene HIRA are expressed in the neural crest and in neural crest-derived tissues in both chick and mouse embryos. By exposing a portion of the premigratory chick neural crest to phosphorothioate end-protected antisense oligonucleotides, ex ovo, followed by orthotopic backtransplantation to the untreated embryos, we have shown that the functional attenuation of cHIRA in the chick cardiac neural crest results in a significantly increased incidence of persistent truncus arteriosus, a phenotypic change characteristic of DGS, but does not affect the repatterning aortic arch arteries, the ventricular function, or the alignment of the outflow tract.     

Immunohistochemical detection of infected neurons as a rapid diagnosis of enterovirus 71 encephalomyelitis

Dementia due to cerebral ischemic lesions is relatively common in the elderly. Since many of these lesions are probably caused by emboli, studying emboli-induced cerebral lesions in rabbits should, hopefully, provide information that is useful when searching for a means of preventing and treating vascular dementia in humans. Using magnetic resonance imaging we have found that N-tert-butyl-alpha-phenyl-nitrone (a free radical scavenger) reduced the number of emboli-induced cerebral microinfarctions in the rabbit cortex but did not have any impact on the number of infarctions found in the subcortical structures. The results suggest that significant amount of free radicals are produced in the ischemic foci located in the cortex, but not in the ischemic foci located in the subcortical structures. This finding may be of importance when considering treatments for cerebral ischemia in humans.     

Optimal control of a queueing system with two interacting servicestations and three classes of impatient tasks

The problem of task selection and service priority is studied for a queueing network with two interacting service stations and three classes of impatient tasks. By using stochastic dynamic programming, a functional equation for the optimal, state-dependent priority assignment policy is derived. Properties of the optimal cost-to-go functions and the optimal policy are established through inductive proofs. It is shown that the optimal policy is governed by two switching surfaces in the three-dimensional state space (one dimension for each task class). For the infinite-time-horizon case, the optimal policy is shown to be stationary. In this case, the optimal cost-to-go function and switching surfaces are obtained numerically by using the overrelaxed Gauss-Seidel method. Sensitivities of the optimal policy with respect to key system parameters are also investigated     

Odor effects of pyridine-montmorillonite in aqueous solution

The threshold odor response of individuals to aqueous solutions of pyridine with and without the presence of sodium montmorillonite was determined at 24 and 40°C. At 24°C there was a significant olfactory effect at pyridine-clay concentrations that produced no effect at 40°C. The olfactory effect depended on the relative sensitivity of the panelists.     

Arsenic analysis and toxicity-a review

The analytical procedures for measuring arsenical compounds in water and the toxicological properties of arsenic and its compounds are critically reviewed. Despite recent advances in instrumental procedures, there is a need to improve preparatory methods. It is postulated that many recently published arsenic concentrations are low because organic-bound arsenic was not released. A need has been identified for expanded information regarding arsenic concentrations in water supplies and potable waters. This need is predicated on the fact that many current water-treatment practices do not remove arsenic.     

Data management of green product development with generic modularized product architecture

Many manufacturers are facing a complex situation in the mixed production environment, in which green and non-green products are fabricated simultaneously. They are losing competitiveness as a downstream supplier due to lacking of a cost-effective approach to managing product variations compliant with different green directives. This paper presents a methodology based on generic modularized product architecture that facilitates data management of green product development. The four-level architecture allows one unified representation for multiple product models. An option control mechanism enables a quick generation of their BOMs (bills of material). A procedure consisting of seven steps is proposed to accomplish this. PDM functions are implemented to demonstrate the effectiveness of the methodology using a real LCD TV family as an example. This work complements the past studies on green product development, which mainly tackled the problem from design, process, and supply chain improvement. In contrast, from a management perspective, the proposed methodology provides a simple but useful tool for small-to-medium-sized enterprises (SMEs) to perform green product development in an economical manner.