Enhanced sustainable electro-generation of a Ni (I) homogeneous electro-catalyst at a silver solid amalgam electrode for the continuous degradation of N2O, NO, DCM, and CB pollutants.

This paper reports the sustainable and enhanced generation of a Ni(I) active electro-catalyst using AgSAE as a cathode material for the sustainable degradation of N2O, NO, dichloromethane (DCM), and chlorobenzene (CB) by electroscrubbing in a series operation. The AgSAE electrode showed 1.66 times higher Ni(I) formation than the Ag metal electrode. The AgSAE achieved 20% ± 2% Ni(I) generation in a highly concentrated alkaline medium, whereas Ag metal only achieved 12% ± 2% Ni(I) generation at the same current density. Electrochemical impedance spectroscopy and voltammetric studies determined that the kinetics of the charge-transfer reaction was also preferential at the AgSAE, with the cathodic peak at -1.26 V vs. Ag/AgCl confirming Ni(I) formation. Initially, the change in the oxygen reduction potential and reduction efficiency of Ni(I) confirmed the removal of N2O, NO, DCM and CB. In addition, the gas Fourier transform infrared (FTIR) spectrum revealed 99.8% removal efficiency of toxic pollutants. Therefore, the regeneration of Ni(I) confirmed the sustainable removal of toxic pollutants. Furthermore, the FTIR spectra revealed the formation of NH3 during the reduction of N2O and NO. On the other hand, DCM and CB were reduced to benzene derivatives in the solution phase. In addition, a plausible reduction mechanism was derived. As a result, the AgSAE cathode exhibited two-fold higher removal efficiency of N2O, NO, DCM, and CB than the previously reported electrodes.

Involvement of pp60c-src with two major signaling pathways in human breast cancer.

The phosphotyrosine residues of receptor tyrosine kinases serve as unique binding sites for proteins involved in intracellular signaling, which contain SRC homology 2 (SH2) domains. Since overexpression or activation of the pp60c-src kinase has been reported in a number of human tumors, including primary human breast carcinomas, we examined the interactions of the SH2 and SH3 domains of human SRC with target proteins in human carcinoma cell lines. Glutathione S-transferase fusion proteins containing either the SH2, SH3, or the entire SH3/SH2 region of human SRC were used to affinity purify tyrosine-phosphorylated proteins from human breast carcinoma cell lines. We show here that in human breast carcinoma cell lines, the SRC SH2 domain binds to activated epidermal growth factor receptor (EGFR) and p185HER2/neu. SRC SH2 binding to EGFR was also observed in a nontumorigenic cell line after hormone stimulation. Endogenous pp60c-src was found to tightly associate with tyrosine-phosphorylated EGFR. Association of the SRC SH2 with the EGFR was blocked by tyrosyl phosphopeptides containing the sequences surrounding tyrosine-530, the regulatory site in the SRC C terminus, or sequences surrounding the major sites of autophosphorylation in the EGFR. These results raise the possibility that association of pp60c-src with these receptor tyrosine kinases is an integral part of the signaling events mediated by these receptors and may contribute to malignant transformation.

Immunochemical analysis of an arginine-rich systemic lupus erythematosus autoepitope.

The MRL mouse strain spontaneously produces antinuclear autoantibodies that recognize DNA and the small nuclear ribonucleoprotein (snRNP) antigens. The monoclonal antibody 2.73 was derived from the lupus prone MRL/n line and is reactive with the 70K protein of the U1 snRNP particle. The epitope recognized by 2.73 was characterized by peptide and inhibition ELISA analysis. Several arginine/aspartic acid (RD) repeats of varying lengths are found in the carboxyl terminus of the 70K protein and are responsible for immunoreactivity with 2.73. We investigated the contribution of charge and found that the immunoreactivity of 2.73 and the 70K protein is specific for the RD repeats. The presentation of the epitope may also contribute to the epitopes immunoreactivity with the 2.73 mouse monoclonal autoantibody.

Serological and clinical aspects of granulocyte antibodies leading to alloimmune neonatal neutropenia.

Eighteen cases of alloimmune neonatal neutropenia (ANN) were analysed for their clinical and serological properties. Pregnancy was normal in all cases, but a 50% incidence of abortion is recorded. With the exception of two premature babies, all newborns were delivered at term. Omphalitis and mild infections of the skin were predominantly present. None of the new-borns died by overwhelming sepsis. The average duration of neutropenia was 11 weeks (range 3-28 weeks). Intravenous IgG therapy was followed by transient remission in 2 of 4 affected newborns. Antibody differentiation revealed in five sera NA1-, in four sera NA2- and in two sera NB1-specific antibodies. In two sera only HLA antibodies were detectable. Complement activating antibodies were determined in 72% of the sera. Screening for granulocyte-specific antibodies in 1016 postpartum sera of unselected women revealed a total of 11 sera (1.1%) reacting selectively with granulocytes, but only four (0.4%) were directed against a known granulocyte-specific antigen. None of the new-born of mothers alloimmunized to granulocyte antigens developed neutropenia, which suggests an incidence of ANN below 0.1%.

[Granulocyte-specific and HLA antibodies in pregnancy: incidence and clinical value]. / Granulozytenspezifische und HLA-Antikörper während der Schwangeschaft: Häufigkeit und klinische Bedeutung.

Postpartum sera of 1,016 unselected women were examined for granulocyte-specific and HLA antibodies. A total of 11 out of 1,016 sera (1.1%) were only reactive with neutrophils. Cytotoxic HLA antibodies were detected in 24%, noncytotoxic HLA antibodies in 4.8% of the sera. All antibodies belonged to the IgG 1 and IgG 3 subclasses. NA1 and NB1 specificity were each determined in one serum, two sera contained NA2-specific antibodies. After 1 year all antibodies were no more detectable. As none of the newborns from immunized mothers developed neutropenia, the incidence of alloimmune neonatal neutropenia seems to be lower than 0.1%.

[Sanitizing a hospital hot water system contaminated with Legionella pneumophila]. / Sanierung eines mit Legionella pneumophila kontaminierten Krankenhaus-Warmwassersystems.

A number of measures were taken to control Legionella pneumophila in a hospital hot water system over a period of 18 months, including (i) raising the temperature of the water leaving the central storage tanks from initially 55-60 degrees C to approximately 73 degrees C, (ii) heat shock treatment of the whole system with water temperatures above 70 degrees C and (iii) increasing the daily return flow from the hospital circulation system from initially 30 m3 to 120 m3. In addition, (iv) three UV irradiation devices were installed on the inlet and outlets of the storage tanks and (v) an attempt was made to decontaminate the water system by means of CO2. Measures (i) and (iii) were demonstrated to be effective for permanent control of Legionellae in the system. Measures (ii) and (v) proved to have only a short term effect of several days and measure (iv) did not show any effect on the presence of Legionellae at all. The extent of Legionella contamination of the water samples correlated negatively with water temperature and depended on the position of the outlets within the hospital. Different pipe materials (copper, plastics) could not be shown to have any influence on the extent of water contamination with Legionella. The findings of the survey indicate that especially the peripheral areas of the hot water system were colonized by Legionellae.

Amino acid uptake by Lemna gibba by a mechanism with affinity to neutral L-and D-amino acids.

Earlier work suggested that amino acid uptake by Lemna gibba cells is a H(+)-cotransport mechanism driven by a proton-electrochemical gradient at the plasmalemma. The present investigations of the transient membrane depolarizations elicited by amino acids and tracer-uptake experiments show that all neutral α-L-amino acids, D-alanine and analogues, like ß-alanine and p-fluorophenylalanine, are transported by the same system. It remains to be seen if there are separate mechanisms for the uptake of acidic and basic amino acids.