Association of LHIα(B870) Polypeptide with Phospholipids During Insertion in the Photosynthetic Membrane of an LHII− Mutant of Rhodobacter capsulatus

Membranes from in vivo labeled cells of Rhodobacter capsulatus U43[pTX35] grown photosynthetically carried 60% of the [³²P]-Pi in the “heavy” fraction (HM) after sucrose gradient sedimentation. Metal-chelating chromatography of either “heavy” or “light” (LM) membrane fractions rendered similar Bchl-protein complex profiles after octyl-glucoside treatment, including most of the radioactivity in the same corresponding elution fraction (F II). Similar labeling distribution of pigment-protein complexes was obtained for membranes of dark-grown cells induced by lowering oxygen tension. Fractions derived from HM showed highly labeled LHIα, whereas the same complex from LM was essentially [³²P]-Pi-free, as revealed by SDS-PAGE followed by autoradiography. Phospholipid analysis showed a similar pattern for membranes isolated from cells photosynthetically or semiaerobically grown, being the most abundant: phosphatidylglycerol, phosphatidylethanolamine, cardiolipin, and phosphatidylcholine. Part of the phospholipids from HM comigrated with LHIα during SDS-PAGE and dissociated from the complexes only after solvent extraction and hydrophobic chromatography. However, a small amount remained always attached to LHIα, indicating an unusual strong interaction. These results suggest the existence of two operationally defined membrane regions carrying LHIα complexes differing in phosphorylation status and protein-phospholipid interaction. Received: 10 August 1996 / Accepted: 10 September 1996     

Serum HE4: An Independent Prognostic Factor in Non-Small Cell Lung Cancer

Human epididymis secretory protein 4 (HE4) is a secreted glycosylated protein encoded by the WAP four-disulfide core domain 2 (WFDC2) gene, located on a chromosome 20 segment that is frequently amplified in many cancers. This study aimed at determining serum HE4 prognostic value in non-small cell lung cancer (NSCLC), following the REMARK guidelines. Serum samples from 346 consecutive patients with histologically proven and previously untreated NSCLC and 41 patients with benign pulmonary disease were collected at the Montpellier-Nimes Academic Hospital. Work-up investigations performed to determine the disease characteristics and treatment algorithms were congruent with international guidelines. HE4 levels in serum were measured with an ELISA test (Fujirebio Diagnostics) that uses two monoclonal antibodies, 2H5 and 3D8, against the C-WFDC domain of HE4. The area under the ROC curve (i.e., overall ability of HE4 to discriminate between controls and patients) was 0.78 (95% confidence interval [CI], 0.738–0.821; z test P <0.0001). Serum HE4 levels were significantly higher in patients with worse performance status, advanced TNM stage and positive nodal status. In the Cox model, overall survival was shorter in patients with high pretreatment serum HE4 (above 140 pmol/L) than in patients with serum H4 level ≤ 140 pmol/L [median survival: 17.7 weeks (95% CI, 11.9 to 24.9) and 46.4 weeks (95% CI, 38.6 to 56.3), respectively; hazard ratio: 1.48 (95% CI, 1.12 to 1.95) for high HE4; adjusted P = 0.0057]. High serum HE4 level at diagnosis is an independent determinant of poor prognosis in NSCLC.     

Gelled diet for screwworm (Diptera: Calliphoridae) mass production

A rearing system based on a diet gelled with Water-Lock G-400, a synthetic superabsorbent (poly(2-propenamide-co-2-propenoic acid, sodium salt)) (WL), was compared with the standard rearing system (liquid diet suspended in acetate fibers) for the mass production of screwworms, Cochliomyia hominivorax (Coquerel). The WL rearing system yielded 2% heavier pupae, 32% higher egg to pupa survival, and required 54% less diet and 88% less labor than the standard rearing system. Other advantages of the WL system include reduced susceptibility to suboptimal environmental conditions and labor practices and characteristics conducive to centralization and mechanization of rearing procedures.     

Identification des cercaires de Schistosoma africains émises par Bulinus umbilicatus,B. truncatus et B. forskalii

Résumé Trois indices chétotaxiques AD, AL et U, des cercaires de quatre espèces pré-identifiées de Schistosoma africains, émises par des Mollusques infestés naturellement ou expérimentalement, ont été calculés. AD et AL correspondant respectivement à la distance relative entre les papilles dorsales et les papilles latérales. U correspond au nombre total des papilles du tronc caudal. La simple comparaison des moyennes arithmétiques d'un ou deux de ces trois indices permet de distinguer les cercaires de Schistosoma haematobium et de S. curassoni émises par Bulinus umbilicatus; les cercaires de S. haematobium et S. bovis émises par B. truncatus; les cercaires de S. bovis et S. intercalatum émises par B. forskalii.

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Identification des cercaires de Schistosoma africains émises par Bulinus umbilicatus, B. truncatus et B. forskalii

Three chaetotaxic indices, AD, AL and U, of cercariae of four pre-identified African Schistosoma species, obtained from natural or experimental infections, were established. AD and AL correspond respectively to the relative distance between the dorsal and lateral papillae. U corresponds to the total number of tail stem papillae. The simple comparison of average values of one or two of these three indices facilitated identification of the cercariae of Schistosoma haematobium and S. curassoni emitted by Bulinus umbilicatus, cercariae of S. haematobium and S. bovis shed by B. truncatus, and cercariae of S. bovis and S. intercalatum emitted by B. forskalii.

     

Synthesis and biological activity profiles of atrial natriuretic factor (ANF) analogs

Several analogs of the atrial natriuretic factor (ANF) were synthesized by the solid-phase method using the acetamidomethyl (Acm) group for sulfhydryl protection. The compounds were tested in a receptor binding assay using bovine adrenal zona glomerulosa cell membranes and in the rat diuresis/natriuresis assay. Substitution of tyrosine in position 116 of ANF(101-126) and of the analog [3-Mpr105]ANF(105-126)(3-Mpr = 3-mercaptopropionic acid) did not alter the biological activity profiles and, therefore, these two analogs in radioiodinated form will be useful for enzymatic degradation and clearance studies. Replacement of 3-mercaptopropionic acid with 2-mercaptopropionic acid in [3-Mpr105]ANF(105-126) resulted in an analog with very low potency in both assay systems, presumably as a consequence of the steric bulk and/or local conformational restriction produced by the methyl group attached to the alpha-carbon in position 105. The analog [3-Mpr105,Nva109]ANF(105-126)(Nva = norvaline) showed very low affinity in the receptor binding assay but displayed considerable diuretic/natriuretic activity. The obtained biological activity profiles suggest that in comparison with other ANF peptides the des-amino ANF(105-126) analogs may have a somewhat longer half-life in vivo, or alternatively, may indicate a more complex situation of ANF receptor or binding site heterogeneity.     

FBXO44 promotes DNA replication-coupled repetitive element silencing in cancer cells

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