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This article examines results of research papers on the use of plasma treatment to enhance hydrophobicity of synthetic textiles. Polymerization/deposition of hydrophobic chemical is commonly used for introducing hydrophobicity. Research works have proven that plasma can treat textiles with a repellant finish comparable to convention wet processing.

The electrochemical behaviors of perfluorinated anionic (FSA and FC-99), cationic (FSD), and nonionic (FSN) surfactants at Hg and Pt electrodes were studied by using the interfacial capacitance measurement and cyclovoltammogram techniques. Their behaviors were also compared with that of the analogous hydrogenated surfactants. In the potential region near the potential of zero charge, both types of surfactants were found to be adsorbed at the Hg/solution interface with their hydrophobic segments oriented toward the electrode surface. However, the surface activity of the perfluorinated surfactants is in general weaker and the saturated adsorption layer is less compact than that of the hydrogenated surfactants at the weakly charged Hg/solution interface. On a more hydrophilic Pt electrode surface and on a strongly charged surface of Hg, both types of surfactants were found to be adsorbed at the electrode/solution interface with their hydrophilic end-groups or segments situated at the interface. On the basis of these results, basic principles for application of perfluorinated surfactants in electrochemical systems were postulated.

LLC-PK1 renal epithelial cells do not appreciably synthesize D-glucose or glycogen from L-lactate under the conditions described. [U-14C]L-lactate is metabolized to [14C]L-alanine and [14C]L-glutamate. Synthesis of alanine but not glutamate is decreased by the transaminase inhibitor, aminooxyacetate. LLC-PK1 cells also produce unlabeled urea in the presence of [14C]L-lactate. Evidence for net gluconeogenesis has thus not been obtained for this cell line. This is interesting because the LLC-PK1 cells possess an active sugar transport system, and both active sugar transport and gluconeogenesis are localized together in vivo in the proximal tubule.

The mechanism of activation of glutamine production by the hindlimb during diabetic ketoacidosis (DKA) was investigated in rats. Muscle glutamine production was estimated to account for over 90% of the total glutamine produced by the hindlimb. DKA produced significant increases in the concentrations of NH4+ and IMP in hindlimb muscles, suggesting that AMP deaminase is activated by DKA. NH4Cl- and HCl-induced acidosis did not produce these changes, indicating either that acidosis itself is not the stimulus for increased AMP deaminase activity or that the more severe degree of acidosis accompanying DKA is necessary for activation. Muscle glutamine concentrations were depressed in DKA. Experiments with isolated epitrochlearis muscle showed that the transport and permeability properties of the muscle cells (as judged by uptake and release of alpha-aminoisobutyrate and glutamine) were not altered by DKA. However, glutamine uptake by muscle cells was significantly inhibited by L-leucine, the concentration of which, along with other branched-chain amino acids, is markedly elevated in DKA.

The arteriovenous difference (release) for glutamine across the hindlimb increases significantly during acute HCl-induced acidosis. This additional amount release by muscle tissue can account for the extra glutamine taken up by the kidney.

To comprehensively evaluate complaints of muscle fatigue, weakness, and myalgias in Persian Gulf veterans (PGV). Background: Approximately 700,000 American troops were deployed to the Persian Gulf during Desert Shield and Desert Storm. Upon return from the Gulf, some PGV developed unexplained illnesses, and special referral centers were established for the evaluation of these patients. Among the most common symptoms of these PGV are fatigue, weakness, and myalgias. An Institute of Medicine committee recommended further exploration into the possible etiologies of these complaints. Methods: Twenty PGV with severe muscle fatigue, weakness, or myalgias that interfered with their daily activities were referred for an extensive prospective neuromuscular evaluation. Routine laboratory studies included serum creatine kinase (CK), erythrocyte sedimentation rate, thyroid function tests, and exercise forearm tests. All patients received nerve conduction studies (NCS), repetitive nerve stimulation, quantitative and single-fiber electromyography (EMG), and muscle biopsies. Results: Manual muscle strength examinations were normal in all patients. Six patients had mildly elevated CKs (range 223 to 768 IU/l); otherwise, laboratory tests were unremarkable. NCS were normal except in 2 patients with carpal tunnel syndrome. Quantitative EMGs were normal. One patient had mildly increased jitter on single-fiber EMG. Muscle biopsies demonstrated minor nonspecific abnormalities in 5 patients (i.e., increased central nuclei, rare necrotic fibers, tubular aggregates). Conclusions: Despite severe subjective symptoms, most of our patients had no objective evidence of neuromuscular disease. Mildly increased CKs or nonspecific histologic abnormalities on muscle biopsy were evident in 8 patients but were not believed to be clinically significant in most. We found no evidence of a specific neuromuscular disorder in any patient. Exposures to toxins during the Persian Gulf War were not likely responsible for our patients' symptoms.

Waste plastics are an environmental problem because of recycling limitations and their resistance to natural decomposition. This research investigates the thermal degradation (pyrolysis) of waste polystyrene in heavy oil as a tertiary recycling method. Kinetic parameters for pyrolysis were obtained, and distillate products from the reaction were characterized by gas chromatography/mass spectroscopy. Four types of heavy oil were used to find which would be most suitable in this process. Complete pyrolysis of polystyrene occurred at temperatures lower than those reported in the literature.

We have purified a glycoprotein from chicken sciatic nerves, sciatin, which has pronounced trophic effects on avian skeletal muscle cells in culture. Recent studies have shown that sciatin is identical to the iron-transport protein, transferrin, in terms of its physicochemical structure, immunological reactivity, and biological activity. To determine whether transferrin is synthesized and released by neuronal tissue, we incubated cultures of dissociated chicken spinal neurons in a medium free of L-leucine containing either L-3H-amino acids or L-[14C]leucine and immunoprecipitated transferrin with highly specific antibodies. The radiolabeled protein precipitated by rabbit heteroclonal, goat heteroclonal, or mouse monoclonal antitransferrin antibodies increased in specific activity in a linear manner for at least 30 min. Synthesis of this protein was abolished by the presence of puromycin (20 micrograms/ml) or cycloheximide (10(-5) M). The disappearance of the radiolabeled protein from cells was linear with a half-life (t 1/2) of 8-10 h. When immunoprecipitates were separated by SDS gel electrophoresis, a prominent band corresponding to transferrin (Mr 84,000) was visualized by staining with Coomassie Blue. However, when such gels were fluorographed, no radioactivity was apparent in the transferrin region of the gel although a prominent radioactive band was visualized at an Mr of 56,000. The protein of Mr 56,000 was not simply a degradation product of transferrin because this particular protein band was not generated by incubating radiolabeled transferrin with unlabeled neuronal homogenates. The protein of Mr 56,000 was purified from embryonic chicken brain and spinal cord by immunoabsorption chromatography on mouse monoclonal antitransferrin IgG conjugated to Sepharose 4B followed by affinity chromatography on immobilized transferrin. The purified protein bound radioiodinated transferrin and was precipitated by rabbit anti-chicken transferrin-receptor antibodies. Furthermore, this receptor protein was found to be localized on the plasma membrane of dorsal root ganglion neurons by immunocytochemistry using the peroxidase-antiperoxidase technique, and by blocking experiments, which showed that antitransferrin receptor IgG could inhibit the binding of fluorescein-conjugated transferrin at 4 degrees C to cultured neurons in vitro. From these data, we conclude that transferrin is not synthesized by cultures of chicken spinal cord neurons, but that the receptor for transferrin is synthesized by these cultures and is precipitated by antitransferrin antibodies as an antigen-receptor complex.