A Meiotic Mutant Defective in Distributive Disjunction in DROSOPHILA MELANOGASTER

The female meiotic mutant no distributive disjunction (symbol: nod) reduces the probability that a nonexchange chromosome will disjoin from either a nonexchange homolog or a nonhomolog; the mutant does not affect exchange or the disjunction of bivalents that have undergone exchange. Disjunction of nonexchange homologs was examined for all chromosome pairs; nonhomologous disjunction of the X chromosomes from the Y chromosome in XXY females, of compound chromosomes in females bearing attached-third chromosomes with and without a Y chromosome, and of the second chromosomes from the third chromosomes were also examined. The results suggest that the defect in nod is in the distributive pairing process. The frequencies and patterns of disjunction from a trivalent in nod females suggest that the distributive pairing process involves three separate events-pairing, orientation, and disjunction. The mutant nod appears to affect disjunction only.     

Malignant Lymphomas of Waldeyer's Ring: Natural History and Survival after Radiotherapy

The natural history of 292 consecutive cases of reticulum cell sarcoma and lymphosarcoma of Waldeyer''s ring and the survival rate after radiotherapy are reported. In our institute since 1928 from 30 to 35% of pharyngeal neoplasms have been lymphomas, and of these 55% have been reticulum cell sarcomas, 21% lymphosarcomas, and 1% Hodgkin''s disease. This high incidence may probably be ascribed to the fact that in all malignant lymphomas, irrespective of the clinical presentation, a systematic biopsy of the whole Waldeyer''s ring was carried out. Pharyngeal lymphomas were confined to Waldeyer''s ring in 19·6% of cases, with initial spread to contiguous cervical nodes in 43·8%, to distant nodes in 24·2%, and to extranodal tissues in 12·4%. Lymphography showed abnormal retroperitoneal lymph nodes in 38·3% of cases. There was gastrointestinal involvement either initially or later in 17·6% of cases. High-energy radiation therapy to both sides of the neck was the treatment of choice for local and regional disease. It achieved a five-year survival rate of 41·9% in the group of 97 patients treated during the past decade. The incidence of relapse (recurrence and new manifestations) was highest in the first year after treatment.     

Oxidative stress in subjects affected by celiac disease

In order to study the role of oxidative stress in celiac disease, protein carbonyl groups, thiobarbituric acid-reactive substance and pentosidine were evaluated in the plasma of nine patients with asymptomatic celiac disease and in a control group (n = 25). Plasma alpha-tocopherol, retinol and lipids were determined in the same samples. The levels of markers of oxidative stress derived from both protein (carbonyl groups) and lipids (thiobarbituric acid-reactive substances) were significantly higher in celiac disease patients, whereas lipoproteins and alpha-tocopherol were significantly lower. These data indicate that in celiac disease, even when asymptomatic, a redox imbalance persists; this is probably caused by an absorption deficiency, even if slight. Dietary supplementation with antioxidant molecules may offer some benefit and deserves further investigation.     

Melatonin and TiO2 NPs Application-Induced Changes in Growth,Photosynthesis, Antioxidant Enzymes Activities and Secondary Metabolites in Stevia (Stevia rebaudiana Bertoni) Under Drought Stress Conditions

Journal of Plant Growth Regulation - Drought stress is one of the major constraints on the growth and productivity of crop plants. Recently, new approaches have been employed in order to cope with...     

Map position of Aldox (Aldehyde-oxidase) and Adh (Alcohol dehydrogenase) loci on autosome II of Musca domestica L.

The Aldox and Adh structural loci of Musca domestica L. belong to autosome II. They code for the enzymes aldehyde oxidase and alcohol dehydrogenase. Both these enzymes have allelic variants with specific electrophoretic mobility, which, on cellogel, are seen as single bands. The Aldox and Adh loci encompass a large map interval, which includes the morphological markers ar, cm, and car. The recombination frequencies between these five loci indicate the alignment Aldox-ar-cm-car-Adh.

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Localisation chez Musca domestica L. des gènes Aldox et Adh codant les enzymes ald\;ehyde oxydase (AO) et alcool déshydrogénase (ADH)

Résumé Chez la mouche, les enzymes AO et ADH, observées par électrophorèse sur cellogel, présentent toutes 2 des formes alléliques exprimées par des bandes ayant une mobilité anodique propre.Les gènes structuraux Aldox et Adh, codant ces formes, sont liés entre eux et situés sur le chromosome 2. Ils se recombinent avec une fréquence élevée d'interchange; ils sont donc séparés par un intervalle important dans lequel sont compris les caractères visibles ar, cm, car. La fréquence des recombinaisons entre caractères visibles et gènes enzymatiques indique l'ordre suivant sur ce segment du deuxième chromosome de la mouche: Aldox, ar, cm, car, Adh.

     

Leukotriene B4 and late asthmatic reactions induced by toluene diisocyanate

We investigated whether leukotriene B4 (LTB4) is released from the lungs of sensitized subjects during asthmatic reactions induced by toluene diisocyanate (TDI). We examined three groups of TDI-sensitized subjects, one after no exposure to TDI, the second 8 h after an exposure to TDI that caused an early asthmatic reaction, and the third 8 h after an exposure to TDI that caused a late asthmatic reaction. We analyzed bronchoalveolar lavage (BAL) fluid by reverse-phase high-performance liquid chromatography and by specific radioimmunoassay. The mean concentration of LTB4 was higher [0.31 +/- 0.09 (SE) ng/ml, range 0.15-0.51] in BAL fluid of sensitized subjects who developed a late asthmatic reaction than in BAL fluid of subjects who developed an early asthmatic reaction (0.05 +/- 0.04 ng/ml, range 0-0.224), and no LTB4 was detectable in the control subjects. We also performed BAL 8 h after TDI exposure on four TDI-sensitized late-dual reactors who were on steroid treatment. In this group of subjects no LTB4 was detectable. These results suggest that LTB4 may be involved in late asthmatic reactions induced by TDI.     

Discrete subcellular localization of phosphoinositidase C beta, gamma and delta in PC12 rat pheochromocytoma cells.

Phosphoinositidase C activity was revealed in nuclei isolated from PC12 rat pheochromocytoma cells incubated with tritiated phosphatidylinositol, phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate. Phosphoinositide breakdown was found to be optimal at neutral pH and Ca++ concentrations ranging from endogenous levels to millimolar values. To characterize the enzymes involved, three monoclonal antibodies directed against the beta, gamma and delta phosphoinositidase C isoforms were employed. A combination of Western blot immunochemical analysis on cytoplasmic and nuclear fractions and of in situ immunocytochemistry on intact cells and isolated nuclei indicated that phosphoinositidase C gamma, though predominantly cytoplasmic, was present in both cell compartments. On the contrary, phosphoinositidase C beta was exclusively localized in the nucleus, whereas phosphoinositidase C delta was restricted to the cytoplasm. These data suggest that inositol lipid breakdown is controlled by different phosphoinositidase C isozymes in the various cell compartments, and support the notion that a separate phosphoinositide signalling system is located in the nucleus.     

Evidence for a genetic duplication involving alcohol dehydrogenase genes inCeratitis capitata

AnAdh duplication is described in the medflyCeratitis capitata. Evidence is presented for two separateAdh ₁ andAdh ₂ structural loci mapping at a distance of 0.49 recombination unit from each other. By deletion mapping theAdh region has been cytologically located near the free end of the left arm of the second chromosome within an area between 2C;3A segments of the polytene chromosome. The genetic analysis of the region aroundAdh has identified seven neighboring genes (Acon ₁,Mpi, Est ₆,Aox, Xdh, Mdh ₂,Lsp _I) which identify the linkage group D. The orientation of loci with regard to the centromere sets the origin of the map of the left arm of the second chromosome close to the twoAdh loci.Research supported by National Research Council of Italy, Special Project RAISA, Subproject N.2, Paper N.200. Grants from I.A.E.A. (International Atomic Energy Agency, Vienna, Austria) and from European Communities Commission, Second R&D Programme Science and Technology for Development also contributed to this work.     

Spectroscopic, structural, and functional characterization of the alternative low-spin state of horse heart cytochrome C

The alternative low-spin states of Fe(3+) and Fe(2+) cytochrome c induced by SDS or AOT/hexane reverse micelles exhibited the heme group in a less rhombic symmetry and were characterized by electron paramagnetic resonance, UV-visible, CD, magnetic CD, fluorescence, and Raman resonance. Consistent with the replacement of Met(80) by another strong field ligand at the sixth heme iron coordination position, Fe(3+) ALSScytc exhibited 1-nm Soret band blue shift and epsilon enhancement accompanied by disappearance of the 695-nm charge transfer band. The Raman resonance, CD, and magnetic CD spectra of Fe(3+) and Fe(2+) ALSScytc exhibited significant changes suggestive of alterations in the heme iron microenvironment and conformation and should not be assigned to unfold because the Trp(59) fluorescence remained quenched by the neighboring heme group. ALSScytc was obtained with His(33) and His(26) carboxyethoxylated horse cytochrome c and with tuna cytochrome c (His(33) replaced by Asn) pointing out Lys(79) as the probable heme iron ligand. Fe(3+) ALSScytc retained the capacity to cleave tert-butylhydroperoxide and to be reduced by dithiothreitol and diphenylacetaldehyde but not by ascorbate. Compatible with a more open heme crevice, ALSScytc exhibited a redox potential approximately 200 mV lower than the wild-type protein (+220 mV) and was more susceptible to the attack of free radicals.