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Objective To determine whether there are differences in adverse pregnancy outcomes in very advanced maternal age (vAMA) women who conceived with assisted reproductive technologies (ART) compared with spontaneous conceptions. Design Retrospective cohort study. Setting Academic tertiary care medical center. Patient(s) A total of 472 women aged ≥45 years who delivered at one institution. Intervention(s) Mode of conception. Main Outcome Measure(s) Maternal and neonatal outcomes. Result(s) For singleton pregnancies, vAMA women who conceived with ART were significantly older (47.0 ± 2.3 vs. 45.6 ± 0.1 years), more likely to be white (88.1% vs. 75.6%), and less parous (0.4 ± 0.9 vs. 1.2 ± 1.8) than vAMA women who conceived spontaneously. They were at significantly increased risk for cesarean delivery (CD) (75.1% vs. 49.7%) and were more likely to undergo elective primary CD without labor (25.4% vs. 9.4%). Risk of retained placenta was also significantly higher (2.7% vs. 0%). Rates of other maternal complications and neonatal outcomes were similar. Subgroup analysis of ART singleton pregnancies did not demonstrate differences in women using autologous oocytes versus donor oocytes. Conclusion(s) Very advanced maternal age women who conceive after ART are more likely to be white, older, primiparous, and are more likely to proceed with an elective CD compared with vAMA women who conceive spontaneously. The increased risk of retained placenta in women who conceive with ART may indicate an underlying risk for placentation defects. [ABSTRACT FROM AUTHOR]

The article focuses on optimum solubility screening, an efficient method to optimize buffer conditions for homogeneity and crystallization of proteins. 24 different buffers ranging from pH 3 to pH 10 are screened using a vapor-diffusion method and very small amounts of protein. The solubility of the protein is first determined by visual examination using a light microscope and those drops that remain clear after 24 hour are further evaluated using dynamic light scattering. The ease of use of this screen and the capability of testing many conditions makes this a very efficient means of searching for the best solvent condition for a particular protein.

Nervous system involvement in systemic lupus erythematosus (SLE) has been linked to the production of autoantibodies that may bind to surface antigens on neuronal cells and cause cellular dysfunction. At present, little is known of the target antigens recognized by these antibodies. The aim of the present study was to examine reactivity to rat brain synaptosomes (RBS) in sera from patients with SLE. Sera from 73 unselected SLE patients and controls were studied. Crude RBS were prepared by differential centrifugation and enriched fractions of synaptosomes (SY-E), myelin (MY-E) and mitochondria (MI-E) were obtained by sucrose density centrifugation. Rat liver (RL) was used for control antigens. Wheat-germ lectin affinity chromatography yielded membrane-enriched fractions of RBS, RL and whole rat brain (WRB). Antibody binding was examined by Western blotting. IgM reactivity was detected in 12/73 sera (16%) and was directed to proteins of 62K, 48K and 37K molecular weight. IgG reactivity was present in 5/73 sera (7%) to proteins of 52K, 48K, 37K and 29K molecular weight. Except for binding to the 52K and 37K proteins these autoantibodies were not detected in control sera. Reactivity was usually absent, or present in reduced amounts, in WRB and RL. Additional experiments revealed that binding of IgM to 62K was found predominantly in SY-E and MY-E fractions, 48K in SY-E and MI-E fractions and 37K in the SY-E fraction. Binding of IgG to 48K and 29K was detected in the SY-E and MI-E, but reactivity to 52K and 37K was restricted to the SY-E fraction. Thus, sera from SLE patients contain antibodies to synaptosomal antigens that may contribute to the neuropsychiatric manifestations of the disease. [ABSTRACT FROM PUBLISHER]

Abstract: Many environmentally important photo- and chemolithoautotrophic bacteria accumulate globules of polymeric, water-insoluble sulfur as a transient product during oxidation of reduced sulfur compounds. Oxidation of this sulfur requires the concerted action of Dsr proteins. However, individual functions and interplay of these proteins are largely unclear. We proved with a ΔdsrE mutant experiment that the cytoplasmic α2β2γ2-structured protein DsrEFH is absolutely essential for the oxidation of sulfur stored in the intracellular sulfur globules of the purple sulfur bacterial model organism Allochromatium vinosum. The ability to degrade stored sulfur was fully regained upon complementation with dsrEFH in trans. The crystal structure of DsrEFH was determined at 2.5 Å resolution to assist functional assignment in detail. In conjunction with phylogenetic analyses, two different types of putative active sites were identified in DsrE and DsrH and shown to be characteristic for sulfur-oxidizing bacteria. Conserved Cys78 of A. vinosum DsrE corresponds to the active cysteines of Escherichia coli YchN and TusD. TusBCD and the protein TusE are parts of sulfur relay system involved in thiouridine biosynthesis. DsrEFH interacts with DsrC, a TusE homologue encoded in the same operon. The conserved penultimate cysteine residue in the carboxy-terminus of DsrC is essential for the interaction. Here, we show that Cys78 of DsrE is strictly required for interaction with DsrC while Cys20 in the putative active site of DsrH is dispensable for that reaction. In summary, our findings point at the occurrence of sulfur transfer reactions during sulfur oxidation via the Dsr proteins. [Copyright &y& Elsevier]