Nimodipine monotherapy and carbamazepine augmentation in patients with refractory recurrent affective illness

We investigated the expression and function of Fas and Fas ligand (FasL) on peripheral blood lymphocytes (PBLs). The cells were stimulated with various cytokines or 12-0-tetradecanoyl phorbol 13-acetate (PMA) plus ionomycin. About 30% of unstimulated PBLs expressed Fas, and the expression was augmented by interleukin-1beta (IL-1beta), IL-2, tumor necrosis factor-alpha (TNF-alpha), interferon-gamma (IFN-gamma), or PMA plus ionomycin. Although only minimal FasL expression was detected on unstimulated PBLs, FasL expression was markedly induced by IL-2 or PMA plus ionomycin, suggesting that Fas and FasL were both expressed on IL-2-stimulated or PMA-plus-ionomycin-stimulated PBLs. Although IL-2-stimulated or PMA-plus-ionomycin-stimulated PBLs were positive for both Fas and FasL, no significant increase in apoptosis was demonstrated in these activated PBLs. In addition, treatment of PBLs with IL-2 or PMA plus ionomycin did not change anti-Fas-induced apoptosis, although these activated PBLs expressed Fas strongly when compared with unstimulated PBLs. Only IL-2-stimulated or PMA-plus-ionomycin-stimulated PBLs killed Fas+ target cells efficiently via the interaction of Fas on target cells with FasL of PBLs. Bcl-2 was constitutively expressed on unstimulated PBLs, but its expression was significantly augmented by IL-2 or PMA plus ionomycin. The expression of Bax was clearly induced only on IL-2-stimulated or PMA-plus-ionomycin-stimulated PBLs and that of other Bcl-2 family proteins such as Bcl-x and Bad could not be detected on human PBLs, including IL-2-stimulated or PMA-plus-ionomycin-stimulated PBLs. Our results suggest that PBLs activated by IL-2 or PMA plus ionomycin express both Fas and FasL and that they kill Fas+ target cells by using FasL on the surface. The resistance of these activated PBLs to Fas-mediated apoptosis may be due to the augmented Bcl-2 expression or the presence of Bcl-2:Bax heterodimers on these cells.     

Outpatient management of asthma during pregnancy

CS-834 is a prodrug of the carbapenem R-95867, developed by Sankyo Co., Ltd., Tokyo, Japan. To investigate the possibility that CS-834 may be the first carbapenem usable in an oral dosage form, its in vitro antibacterial activity (as R-95867) and in vivo antibacterial activity were compared with those of cefpodoxime proxetil, cefditoren pivoxil, cefdinir, ofloxacin, imipenem, and amoxicillin. R-95867 had high levels of activity against methicillin-susceptible staphylococci and streptococci, including penicillin-resistant Streptococcus pneumoniae, as well as Neisseria gonorrhoeae, Moraxella catarrhalis, the members of the family Enterobacteriaceae (with the exception of Serratia marcescens), Haemophilus influenzae, and Bordetella pertussis; for all these strains, the MICs at which 90% of tested strains are inhibited (MIC90s) were 1.0 microg/ml or less. Against methicillin-resistant staphylococci, enterococci, Serratia marcescens, Burkholderia cepacia, Stenotrophomonas maltophilia, and Acinetobacter calcoaceticus, R-95867 showed activity comparable to or slightly less than that of imipenem, with MIC90s ranging from 2 to >128 microg/ml. The in vivo efficacy of oral CS-834 against experimental mouse septicemia caused by gram-positive and gram-negative bacteria was better than that of comparative drugs. In murine respiratory infection models, the efficacy of CS-834 reflected not only its potent in vitro activity but also the high levels present in the lungs.     

Comparison of two algorithms and their associated charges when evaluating adrenal masses in patients with malignancies

OBJECTIVE: This study was performed to compare two proposed algorithms used when evaluating an adrenal mass discovered during staging evaluation of a patient with a known malignancy. Such evaluation was meant to lead to determination of the relative charges associated with each algorithm. SUBJECTS AND METHODS: Fifty-four patients with known malignancies who required evaluation of an adrenal mass underwent both chemical shift imaging (CSI) and CT-guided for CSI. The hospital charges incurred for each procedure and any associated complications were normalized using national relative-value scale charges and conversion factors. A decision analysis was performed to compare the relative charges that would have been incurred if adrenal MR imaging had been performed in all patients, followed by CT-guided biopsy only in those patients with MR findings not diagnostic of adrenocortical adenoma, and the relative charges incurred if only CT-guided adrenal biopsy had been performed in every patient. RESULTS: Twenty-three (43%) of 54 adrenal masses were shown to be metastases by CT-guided biopsy. The sensitivity and specificity of CSI for the diagnosis of adrenocortical adenoma were 94% and 100%, respectively. The charges incurred by performing MR imaging as the initial examination with subsequent CT-guided biopsy only in those patients with CSI findings not diagnostic of adenoma would have been similar to those incurred by first performing CT-guided adrenal biopsy in every patient. CONCLUSION: CSI is an accurate, noninvasive technique for evaluating adrenal masses in patients with cancer. If CT-guided biopsy is used only when CSI is not diagnostic of adrenocortical adenoma, the associated charges would be virtually the same as when CT-guided biopsy is performed as the first test in every patient. Moreover, biopsies could have been avoided in 54% of these patients.     

A dominant-negative clathrin mutant differentially affects trafficking of molecules with distinct sorting motifs in the class II major histocompatibility complex (MHC) pathway

The role of clathrin in intracellular sorting was investigated by expression of a dominant-negative mutant form of clathrin, termed the hub fragment. Hub inhibition of clathrin-mediated membrane transport was established by demonstrating a block of transferrin internalization and an alteration in the intracellular distribution of the cation-independent mannose-6-phosphate receptor. Hubs had no effect on uptake of FITC-dextran, adaptor distribution, organelle integrity in the secretory pathway, or cell surface expression of constitutively secreted molecules. Hub expression blocked lysosomal delivery of chimeric molecules containing either the tyrosine-based sorting signal of H2M or the dileucine-based sorting signal of CD3gamma, confirming a role for clathrin-coated vesicles (CCVs) in recognizing these signals and sorting them to the endocytic pathway. Hub expression was then used to probe the role of CCVs in targeting native molecules bearing these sorting signals in the context of HLA-DM and the invariant chain (I chain) complexed to HLA-DR. The distribution of these molecules was differentially affected. Accumulation of hubs before expression of the DM dimer blocked DM export from the TGN, whereas hubs had no effect on direct targeting of the DR-I chain complex from the TGN to the endocytic pathway. However, concurrent expression of hubs, such that hubs were building to inhibitory concentrations during DM or DR-I chain expression, caused cell surface accumulation of both complexes. These observations suggest that both DM and DR-I chain are directly transported to the endocytic pathway from the TGN, DM in CCVs, and DR-I chain independent of CCVs. Subsequently, both complexes can appear at the cell surface from where they are both internalized by CCVs. Differential packaging in CCVs in the TGN, mediated by tyrosine- and dileucine-based sorting signals, could be a mechanism for functional segregation of DM from DR-I chain until their intended rendezvous in late endocytic compartments.     

Escherichia coli ribosomal protein L3 stimulates the helicase activity of the Bacillus stearothermophilus PcrA helicase

Escherichia coli ribosomal protein L3 stimulates the in vitro helicase activity of Bacillus stearothermophilus PcrA helicase upon a variety of different substrates. L3 has no intrinsic helicase or ATPase activity nor is it able to stimulate the ATPase activity of PcrA. Gel mobility shift assays revealed that the affinity of PcrA for a variety of different DNA species (single-stranded, nicked and 3'-tailed) was enhanced in the presence of L3. We suggest that the stimulatory effect of L3 upon the helicase activity of PcrA is mediated via a protein-protein interaction which promotes cooperative binding of PcrA to its DNA substrate. This activity of L3 appears to be specific for PcrA helicase.     

Channels formed by the transmembrane helix of phospholamban: a simulation study

Phospholamban is a small membrane protein which can form cation selective ion channels in lipid bilayers. Each subunit contains a single, largely hydrophobic transmembrane helix. The helices are thought to assemble as a pentameric and approximately parallel bundle surrounding a central pore. A model of this assembly (PDB code IPSL) has been used as the starting point for molecular dynamics (MD) simulations of a system consisting of the pentameric helix bundle, plus 217 water molecules located within and at either mouth of the pore. Interhelix distance restraints were employed to maintain the integrity of the helix bundle during a 500 ps MD simulation. Water molecules within the pore exhibited reduced diffusional and rotational mobility. Interactions between the alpha-helix dipoles and the water dipoles, the latter aligned anti-parallel to the former, contribute to the stability of the system. Analysis of the potential energy of interaction of a K+ ion as it was moved through the pore suggested that unfavourable interactions of the cation with the aligned helix dipoles at the N-terminal mouth were overcome by favourable ion-water interactions. Comparable analysis for a Cl ion revealed that the ion-(pore + water) interactions were unfavourable along the whole of the pore, increasingly so from the N- to the C-terminal mouth. Overall, the interaction energy profiles were consistent with a pore selective for cations over anions. Pore radius profiles were used to predict a channel conductance of 50 to 70 ps in 0.2 M KCl, which compares well with an experimental value of 100 ps.