Action comparée de la 6-furfurylaminopurine et de la 6-(γ, γ-dimethylallylainino)purine sur la croissance, l'activité peroxydasique, la teneur en chlorophylles et en caroténoïdes

Comparative Effects of 6-Furfurylaminopurine and 6-(γ, γ-Dimethylallylamino) purine on Growth, Peroxidase, Chlorophyll and Carotenoid Content. — 6-Furfurylaminopurine (FAP) and 6-(γ, γ-dimethylallylamino) purine (IPA) both inhibit root growth and cause an increase in peroxidase activity. When used at 10^?8 and 10^?8M, IPA stimulates elongation of the coleoptile test, at 10^?4M both FAP and IPA provoke an inhibition. FAP and IPA maintain a high level in chlorophylls and carotenoids in floating leaves discs. In all these experiments, IPA has thus a higher effect than FAP.     

Interaction du photopériodisme et des effets de la zéatine, du saccharose et de ľeau dans la floraison du Chenopodium polyspermum

Interaction of photoperiodism and zeatin, sucrose and water effects on the flowering of Chenopodium polyspermum Root removal in Chenopodium polyspermum, a quatitative short-day plant, enhances flowering under non-inductive conditions. Presence of roots may be mimicked by zeatin applications on buds. Induction of flowering by short days may be counteracted by applications of zeatin, and appearance of flowers depends on the balance between number of inductive short days and zeatin quantity applied. Sucrose added in the culture medium or applied on buds acts as zeatin. Applications of water on buds may also delay flowering. These results show the plurifactorial regulation of the floral development of this plant. The relations between the non-specificity of the induction and the specificity of the morphogenetic response are discussed.     

Structures de la cabuamine et de la vincorine

Cabuamine is identified as O-methyl-hydrogeno akuammine.     

Influence de l'intensité et de la longueur d'onde de la lumière sur le rendement des radicaux libres dans les semences de tomate et de carotte

Influence of light intensity and wavelength on the yield of free radicals in seeds of tomato and carrot.
Seeds of tomato ( Lycopersicum esculentum L. cv. Gribovsky-1180) and carrot ( Daucus carota L. cv. Santanet) were irradiated by continuous light of different wavelengths (white, blue, green, red, far-red and He-Ne laser) and different power density. Free radical output was measured using Electron Spin Resonance spectra (ESR). The dependence of the content of free radicals (FR) on the light power density was established. The yield of FR in the seeds irradiated with monochromatic light of the same power density was inversely proportional to the wavelength. The ESR spectra showed maximum absolute number of FR for white light. Successive irradiations gave cumulative effects on the output of free radicals in both directions: increase by the action of white light and decrease by the action of red and far-red light. The contact of irradiated seeds with steam decreased the amount of FR.     

La stratigraphie et le Paléolithique du complexe saalien dans la région de la Saale et de l’Elbe

Some sediment sequences were known in the Elbe-Saale region. They enable a subdivision of the Saale complex, that is from Neumark Nord (Geisel valley), from Weimar-Ehringsdorf and Bad Kösen-Lengefeld (Saale valley). According to it, there are two interglacials between the Saalian groundmoraine (s.str.) and the Eemian. They are characterized by a strong subcontinental climatic influence, which could not be observed in the other interglacials of the Elbe-Saale region. The interglacials are connected with find horizons from the Middle Palaeolithic. They are concisely described here with their inventories.     

Action de quelques phytohormones sur la respiration et ľabsorption du phosphate par des disques de tubercules de pomme de terre en survie

Action of some phytohormones on the respiration and on the absorption of phosphate by aging potato tuber discs. Discs of potato tuber incubated in aerated medium show an increase of the rates of respiration and phosphate absorption with aging time; the rates increase by two and nine respectively during the time period between 5 and 24 h of aging. Adenine or some N-6 substituted adenines [benzylaminopurine (BAP), furfurylaminopurine (FAP), methylaminopurine (MAP)], which present variable degrees of cytokinin activity, partially inhibit the increase of the rate of phosphate absorption and, to a lesser extent, the increase of the rate of respiration. Also abscisic acid (ABA), indole 3-acetic acid (IAA), and gibberellic acid (GA₃) produce inhibition of the increase of the rate of phosphate absorption with varied effects on the respiration. With regard to phosphate uptake, the effects of ABA, 1AA and GA₃ were additive to those of BAP. The effects on respiration were different from the effects on phosphate uptake, so that there is no direct relationship between inhibition of respiration and inhibition of phosphate uptake.     

Applications biologiques de la spectroscopie Raman de résonance et de la spectroscopie micro-Raman de résonance

Advantages are given to illustrate the possibilities of resonance Raman spectroscopy in the studies of biological systems.A relation giving the size of porphinato-core of metalloporphyrins from resonance Raman frequency is proposed. It can be applied to heme, even in lived state.By illuminating the sample through a microscope, resonance Raman effect can be collected from 1 (μm)² of sample. Spectra of a vegetal-cell wall (pimento) and of a red corpuscle (hemoglobin) are shown as examples.     

Stimulation par la lumière rouge lointain de la synthèse de la δ-aminolévulinate déshydratase des cotylédons de radis

Stimulation of de novo synthesis of δ-aminolevulinate dehydralasc of radishes grown under far-red light .
Density labelling studies of δ-aminolevulinate dehydratase (ALAD) in cotyledons of radish ( Raphanus sativus L. cv. Longue Rave Saumonée) seedlings demonstrate that far-red light stimulates de novo synthesis of ALAD and that the turn-over of this enzyme is very poor. Cycloheximide reduces considerably both the increase of ALAD activity and the incorporation of deuterium in ALAD, which indicates that ALAD synthesis depends upon cytoplasmic ribosomes.     

Synthèse et structure de la poly-O-carbobenzoxy L- tyrosine et de copolymères de O-carbobenzoxy L-tyrosine et de glutamate de benzyle ou d'aspartate de benzyle

The optical rotatory dispersion of copolymers of O-carbobenzoxy-L -tyrosine and benzyl L (or D )-glutamate as well as benzyl L -aspartate, dissolved in nonpolar solvent, has been studied. Moffitt's equation permits the determination of b₀ coefficients whose variation, with varying composition in amino acid residues, suggests that the molecules of poly-O-carbobenzoxy-L -tyrosine have a helical structure similar to that of poly-(benzyl L -glutamate). Results obtained from infrared spectroscopy and x-ray diffraction show that the copolymers possess a helical conformation in the solid state, even when they are very rich in carbobenzoxy-L -tyrosine residues. The value of the b₀, coefficient for poly-O-carbobenzoxy-L -tyrosine may be explained by a regular stacking of the chromophore groups around the helical backbone. The ordering of the molecules of this polymer in a purely helical structure seems favored by the insertion of a small number of foreign residues in the polypeptide chain.     

Affections dermatologiques de la muqueuse genitale masculine et de la verge

A wide variety of infectious, inflammatory or dysplasic disorders may affect both male genital skin and mucous membranes. We review here the clinical patterns or the most common disorders. The diagnosis is based upon the existence of erythematous balanitis, erosions or ulcerations. Among infections, candidiosis, genital herpes, HPV papillomas are the most common. Most of inflammatory skin disorders may affect the male organ, especially psoriasis, lichen planus or erosive lichen planus, allergic dermatitis, auto-immune bullous dermatoses, drug-reactions. Chronic balanitis, or recurrent inflammatory balanitis, lichen sclerosus may lead to the emergence of intraepithelial neoplasias (PIN) or invasive carcinomas. The management of genital lesions needs in fact: the observation or oral mucous membrances and of the skin it-self with a special attention to very peculiar body sites for the presence of typical skin disease lesions; a surgical biopsy for microscopic observation; in some cases immunopathology with direct and indirect immunofluorescence for the diagnosis of auto-immune disorders.     

Influence relative de la BAP et de l'IBA sur la néoformation de bourgeons et de racines sur les plantules du Biota orientalis (Cupressacées)

Relative influence of BAP and IBA on the induction of adventitious buds and roots on plantelts of Biota orientalis (Cupressaceae)
Both cytokinin (BAP) and auxin (IBA) have an influence upon the intensity of adventitious bud induction in vitro on hypocotyls of Biota orientalis .
Increase in either the concentration or the length of contact with cytokinin enhances the mean number of neoformed buds per explant, while that of auxin results in an increase of the mean number of reactive explants as well as in the nature of neoformations. Auxin contributes to a restoration of the induction when the length of contact with cytokinin is too short. However, this synergism is only observed when the contract with IBA is simultaneous or follows that with contract with BAP.
Rhizogenesis is also influenced by the auxin-cytokinin balance. An increase in the duration of contact with IBA is always followed by an increased in the mean number of explants forming roots. This organogenesis may be partially or completely inhibited if the duration of contact with cytokinin – before, simultaneously or after that with auxin- exceeds two weeks.