The Quality of Well-Being scale in asymptomatic HIV-infected patients. HNRC Group. HIV Neural Behavioral Research Center

Mice bearing mutations at either of two loci, dominant White spotting(W) or Steel(Sl), exhibit development defects in hematopoietic, melanocytic and germ cells. Genetics studies have shown that the SI locus encodes the Steel factor (SF), which is the ligand for the tyrosine kinase receptor c-kit, the product of the W locus. SF is synthesized in membrane-bound form and can be processed to produce a soluble form. Cell-cell interaction is important in the production of normal blood cells in vivo and in vitro and in the cellular expansion of leukemic cells. We discuss here how SF decreases the requirements in cell interaction for blast colony formation in acute myeloblastic leukemia (AML) and the presence of membrane-bound SF possibly contributes to the density-dependent growth of the AML blasts. We explain that SF is mainly a survival factor for hematopoietic cells, of little proliferative effect, which maintains CD34+ hematopoietic cells in an undifferentiated state. These properties would potentially allow the maintenance of hematopoietic cells in culture for the purpose of marrow purging or gene therapy. The activation of the c-kit signal transduction pathway may play a significant role in the development of many types of non-hematological malignancies by disrupting normal cell-cell interactions and allowing the growth of cancer cell populations. In summary, the properties of the SF indicate it has a role for survival signals during the process of normal differentiation, AML proliferation and in the maintenance of many c-kit+ tumors.     

Charge movements in the 13-cis photocycles of the bacteriorhodopsin mutants R82K and R82Q

We have examined light-induced currents in oriented membranes of the bacteriorhodopsin mutants R82K and R82Q. Our results suggest that two photocurrent components found in R82K, with 30 and 300 microseconds lifetimes, are due to the photocycle of the 13-cis rather than the all-trans form of the pigment. We investigated the pH dependence of these components and their correspondence to absorbance changes at 660 nm characteristic of photointermediates of the 13-cis cycle. The presence of a D2O effect suggests that the charge motions producing these photocurrents are related to proton or protonated amino acid movement within the molecule. The current amplitudes depend on the protonation states of at least two residues, D85 and (probably) E204. In R82Q, a 10 microseconds photocurrent is observed that also depends on the protonation state of D85 and is similar to the 30 microseconds current in R82K. We attempt to explain these currents in terms of a model for interacting residues in the extracellular half of the bacteriorhodopsin channel.     

Nuclear structure of 178Lu

A retrospective study of infections due to Pasteurella (P.) and related groups was performed between the Pasteurella National Center and Nancy's hospital from 1985 to 1991. Among the 958 cases recorded, wound infections (bites, scratches and punctures) were the common forms of pasteurellosis (66%) caused by P. multocida (48%), P. canis (11%), P. dagmatis (5%), P. stomatis (4%), and in few cases by groups EF-4 and M-5 (14 and 13%, respectively). In human infections unrelated to animal wounds, respiratory tract diseases and bacteremia-septicemia were the predominant infections with respectively 19 and 11%, and caused by P. multocida. Next in importance were urogenital (2.5%), abdominal (1%) and central nervous system (< 1%) infections. The majority of animal bite wound infections was treated with penicillins or tetracyclines; with other forms, penicillins and cephalosporins were more likely.     

Gangrene of the penis after implantation of penile prosthesis: case reports, treatment recommendations and review of the literature

We report 3 cases of gangrene of the penis seen at our institution after penile prosthesis implantation. All 3 patients had insulin-dependent diabetes mellitus. Amputation was required in 2 patients. Aggressive debridement in conjunction with hyperbaric oxygen prevented amputation in the third patient.     

Iatrogenic ureteral lesions. Apropos of 8 cases

The authors report 8 cases of iatrogenic ureteric lesions, induced by gynaecological or obstetric operations. The diagnosis was based on a recent history of surgery, clinical features, abdominal ultrasonography and IVU. Treatment consisted of ureterovesical reimplantation.     

Growth factor induction of nitric oxide synthase in rat pheochromocytoma cells

Members of the beta isozyme subfamily of phosphatidylinositol-specific phospholipase C (PLC) are stimulated by alpha subunits and betagamma dimers of heterotrimeric guanine-nucleotide-binding proteins (G proteins). Myeloid differentiated human HL-60 granulocytes and bovine neutrophils contain a soluble phospholipase C, which is stimulated by the metabolically stable GTP analogue guanosine (5'-->O)-3-thiotriphosphate (GTP[S]). To identify the component(s) involved in mediating this stimulation, the relevant polypeptide(s) was resolved from endogenous phospholipase C and purified from bovine neutrophil cytosol by measuring its ability to confer GTP[S] stimulation to exogenous recombinant PLCbeta2. The resolved factor, which behaved as 48-kDa protein upon gel filtration, stimulated PLCbeta2 but not PLCbeta1 or PLCdelta1. Activation of phosphatidylinositol 4-phosphate 5-kinase was not involved in this stimulation. The purified stimulatory factor consisted of two polypeptides of molecular masses of approximately 23 kDa and 26 kDa. The protein stimulated a deletion mutant of PLCbeta2 that lacked a carboxyl-terminal region necessary for stimulation by members of the alpha(q) subfamily of the G-protein alpha subunits. The results of this study suggest that a GTP-binding protein distinct from alpha(q) subunits, probably a low-molecular-mass GTP-binding protein associated with a regulatory protein, is involved in isozyme-specific activation of PLCbeta2.     

Acute myelomonocytic leukemia preceded by secondary amenorrhea and presenting with central diabetes insipidus: a case report

The antigenic components of Fasciola gigantica somatic extract were revealed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and immunoblotting technique using sera from patients with F. gigantica infection, patients with clinically diagnosed fascioliasis, patients with other infections/illness and healthy adults. By SDS-PAGE, it was found that the somatic product comprised more than 22 polypeptides. Immunoblotting analysis revealed at least 13 components which were strongly recognized by sera of patients with fascioliasis. These antigenic components had molecular weights ranging from less than 14.4 to more than 94 kDa. One antigenic component, i.e. 38 kDa was found to give a consistent reaction with sera of patients with fascioliasis (100% sensitivity and 96.7% specificity). The finding suggests that the 38 kDa components may be a potential diagnostic antigen for fascioliasis.     

Nitric oxide modulates neuropeptide Y regulation of ion transport in mouse ileum

The possible involvement of nitric oxide in the regulation of intestinal ion transport induced by neuropeptide Y (NPY) was investigated by evaluating the effects of NG-methyl-L-arginine (L-NMA), L-arginine and S-nitroso-N-acetylpenicillamine (SNAP) on NPY activity in mouse ileum mounted in Ussing chambers in vitro. Serosal NPY (10 nM) produced a sustained decrease in basal transmural short circuit current (Isc) and potential difference without altering the tissue conductance. Pretreatment of tissues with L-arginine (3 mM), but not D-arginine (10 mM), blocked the NPY-mediated changes in Isc. This L-arginine effect on NPY activity was reversed by L-NMA (3 mM), and not by NG-methyl-D-arginine (10 mM). The L-arginine effect on NPY activity was concentration-related with an A50 (95% CL) value of 1.6 (0.9-2.3) mM. In contrast to L-arginine, L-NMA (1 mM) pretreatment of tissues produced an enhancement of NPY activity, resulting in a 3.8-fold leftward displacement of the NPY concentration-response curve; NG-methyl-D-arginine was without effect. The effect of L-NMA on NPY activity was concentration-related with an A50 (95% CL) value of 45.3 (23.2-68.8) microM. Serosal application of SNAP, a nitric oxide donor, produced a concentration-related decrease in basal Isc and potential difference without altering tissue conductance with an A50 (95% CL) value of 22.5 (11.1-40.5) microM. Pretreatment of tissue with SNAP (100 microM) reduced the NPY activity with rightward displacement of NPY concentration-response curve. Pretreatment of tissues with L-arginine also blocked the reduction of Isc by [D-Pen2, D-Pen5]enkephalin (10-30 nM), H2N-Tyr-D-Ala-Phe-Glu-Val-Val-Gly-NH2 (10-30 nM) and somatostatin (0.3-1.0 microM), but had no effect on norepinephrine (0.1-0.3 microM)-induced decrease in mouse ileal Isc. These results show that [fgc]l-arginine and SNAP block NPY-mediated changes in ion transport, suggesting that nitric oxide may play a role in the regulation of NPY-mediated ion transport in the mouse ileum.