A Simple Method for Isolating DNA of High Yield and Quality from Cotton (shape Gossypium hirsutum L.) Leaves

An easy, reproducible and fast procedure to isolate DNA from cotton leaves is described. The addition of 0.5 M glucose in the extraction buffer avoids browning by polyphenolic compounds and improves the quality of DNA for molecular analysis. The DNA yield ranged between 150–400 mg per gram of fresh tissue. The DNA was suitable for digestion by restriction enzymes and amplificatiion by Taq DNA polymerase.     

Production of trace levels of carbon monoxide during methanogenesis on acetate and methanol

Summary Production of trace levels of carbon monoxide was consistently observed in the off-gas of a laboratory anaerobic digester fed Waste Activated Sludge. Inocula from this digester was enriched for acetate and methanol utilizing methanogenic populations. These enriched inocula were then monitored in batch assays for carbon monoxide and hydrogen production. Results demonstrated that carbon monoxide is produced during methanogenesis on both substrates. Subsequent utilization of CO was observed to occur after methane production was essentially complete for the assays conducted with methanol. Carbon monoxide evolution during methanogenesis on acetate displayed a markedly different trend from that observed from methanol.     

Polyamine modification in human breast tumors after short treatment with tamoxifen

The authors measured estrogen receptors, and polyamine (putrescine, spermidine and spermine) in breast tumors from patients (n = 23) who had received tamoxifen for a few days (5-10) before surgery. Women undergoing mastectomy without any preoperatory treatment were selected as the control group (n = 44). As already reported about in vitro experiments, the treatment resulted in a significant lowering of the spermidine to spermine ratio. Such a modification was larger in the ER positive tumors then in the ER negative ones and it seems to be related to the regression process of the drug-responsive tumors. On the basis of the experimental data the authors suggest the development of a in vivo tamoxifen-sensitivity test.     

Production of Poly-β-Hydroxyalkanoic Acid by Pseudomonas cepacia

The possibility of using the nutritionally versatile bacterium Pseudomonas cepacia to produce poly-β-hydroxyalkanoic acid was evaluated. Chemostat culture showed that growth of P. cepacia became nitrogen limited when the molar carbon-to-nitrogen ratio of the medium fed into the fermentor was above 15. When grown under nitrogen limitation in batch culture with fructose as the sole source of carbon, P. cepacia accumulated poly-β-hydroxybutyric acid (PHB) in excess of 50% of the dry weight of its biomass. In batch culture, almost no PHB was produced until the onset of nitrogen limitation. After this point, PHB was produced at a linear rate of 0.12 g liter⁻¹ h⁻¹ (from a constant value of 1.6 g of cellular protein liter⁻¹). PHB produced by P. cepacia had a weight-average molecular weight of 5.37 × 10⁵ g mol⁻¹ and a polydispersivity index of 3.9. Poly(β-hydroxybutyric acid-β-hydroxyvaleric acid) copolymer was produced with a poly-β-hydroxybutyric acid-poly-β-hydroxyvaleric acid ratio of up to 30% by weight when propionic acid was added to the medium.     

Alkaline phosphatases and steroid receptors in human breast cancer

Estrogen receptors (ER), progesterone receptors (PR) and alkaline phosphatases (AP) were measured in 150 tumors from patients who underwent mastectomy for primary breast cancer. The percentage of ER positive samples was inversely related to the AP activity ranging from 88.9% in low activity samples (less than 30 U/mg prot.) down to 30.6% in the high activity ones (greater than 400 U/mg prot.). When considering only ER positive samples, the ER content was inversely related to the AP activity. This could not be demonstrated for PR. Therefore, the authors suggest the hypothesis that in human breast cancer, the AP may play a role in the dephosphorylation of the ER molecule and in the consequent modulation of its binding capability.     

Effect of lead on the reaction of O-demethylase in p-nitro anisole in the cladoceran Moina macrocopa

The presence of the Mixed-Function Oxydase (MFO) system, in Moina macrocopa was detected through the transformation of p-nitroanisole to para-nitrophenol. The presence of this enzymatic system suggested that this cladoceran participates in the biotransformation of xenobiotics in aquatic ecosystems. This capacity, in conjunction with the aquatic flea's high tolerance to environmental stress, suggested that M. macrocopa could be used in bioremediation efforts to increase ecosystem health. The effects of lead on the MFO system in M. macrocopa, were also studied. Lead acted as an inhibitor of the enzymatic complex. Therefore, induction of MFO-activity as an early warning may not work in waterbodies affected by both inducers of MFO and inhibitors like lead.     

Immunohistopathological studies of blastomycosis: the use of labeled specific antigens in a hamster model of disease

We applied a modified immunofluorescence and immunoperoxidase method, utilizing labeled Blastomyces dermatitidis antigens, to look for specific antibody-bearing B/ plasma cells in the tissue infiltrates of blastomycosis lesions induced in hamsters. No specific anti-blastomyces antibodies were detectable by this method, although such antibodies were present in blood samples as demonstrated by routine immunodiffusion techniques. These studies suggest that humoral immune reactions do not play a major role in the pathogenesis of lesions of blastomycosis in hamsters.     

Comparative value of four arcelin variants in the development of dry bean lines resistant to the Mexican bean weevil

Wild Phaseolus vulgaris L. accessions containing arcelin codominant alleles 1 through 5 were reconfirmed and characterized for resistance to the Mexican bean weevil, Zabrotes subfasciatus (Boheman) (Coleoptera: Bruchidae). Accession G 02771 (arcelin 5) had the highest level of antibiosis resistance, followed by G 12952 (arcelin 4), G 12882 (arcelin 1) and G 12866 (arcelin 2). Arcelin 3 accessions conferred the lowest levels of resistance. As the presence of arcelin is inherited as a single dominant gene, a backcross breeding program has been used to transfer resistance to the Mexican bean weevil from wild beans to bean cultivars using serological techniques to detect the presence of arcelin and replicated insect feeding tests to measure resistance levels. Progeny containing arcelin 1 showed resistance equal or superior to that of the resistant check. Arcelin 2-deerived lines had intermediate levels of resistance while no resistant progenies were obtained from crosses with arcelin 3 and 4 sources. Results are discussed in relation to the deployment of arcelin alleles in bean cultivars.

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Valeurs comparées de 5 types d'arcéline dans l'obtention de lignées de Phaseolus vulgaris résistantes à Zabrotes subfasciatus

Résumé La résistance à Zabrotes subfasciatus est associée à la présence d'arcéline, une nouvelle protéine des graines, découverte chez quelques populations de Phaseolus vulgaris. 5 types d'arcéline, hérités comme allèles codominants ont été décrits dans la littérature. Nous avons reprécisé les différentes populations contenant différents types d'arcéline et caractérisé leurs résistances à Z. subfasciatus. La population G 02771, correspondant à l'arcéline 5, présente la résistance la plus élevée par antibiose, suivie de G 12952 (arcéline 4), G 12882 (arcéline 1) et G 12866 (arcéline 2). Les populations contenant l'arcéline 3 présentent le moins de résistance à Z. subfasciatus.Un programme de croisements en retour associé à des tests sérologiques pour déceler la présence d'arcéline chez les descendants jeunes et des expériences répétées d'alimentation par les insectes vec BC2F₃ a été réalisé pour transférer la résistance de populations naturelles à des cultivars de haricots. Les lignées, provenant de croisements avec des populations sauvages avec de l'arcéline 1, ont été fortement résistantes à Z. subfasciatus. Les lignées contenant de l'arcéline 2 ont été considérées comme ayant une résistance intermédiaire. Les lignées avec arcélines 3 et 4 étaient sensibles. Les raisons de l'échec du transfert de la résistance élevée des parents contenant de l'arcéline 4, sont inconnues. On a constaté que la concentration de l'arcéline dans les lignées contenant cet allèle était très faible, tandis que la concentration en arcéline 1 restait remarquablement élevée. Les recherches sont poursuivies pour déterminer les raisons de l'absence de transfert de l'arcéline 4 chez les descendants contenant cet allèle. Quoi qu'il en soit, les caractéristiques agronomiques et les qualités des lignées résistantes (codées RAZ) ont été évaluées en vue d'une diffusion pour les programmes nationaux de recherche des pays de basses altitudes intertropicaux ou Zabrotes subfasciatus fait des dégâts importants.