Rigenerazione E Moltiplicazione Vegetativa in Vitro in Enteromorpha Compressa (L.) Grev.

Abstract

Regeneration and vegetative multiplication in ENTEROMORPHA COMPRESSA (L.) Grev. — Fragments of young filaments of Enteromorpha compressa were cultured in order to determine its regenerative and multiplicative power and time limit.

The original fragments cultured in vitro produced a new strain of aposporical plants, by means of buds. These aposporical individuals, when grown up, bear rhizoids with propagula from which a new strain of free algs take place. The latter generation is supplied with a fixation apparatus and show regular shape and clear polarity.     

Functional trait space and redundancy of plant communities decrease toward cold temperature at high altitudes in Southwest China

Science China Life Sciences - Plant communities in mountainous areas shift gradually as climatic conditions change with altitude. How trait structure in multivariate space adapts to these varying...     

Follicle duct cell ultrastructure and eggshell formation in Triops cancriformis (crustacea,notostraca)

Electron microscopy of the cells of the follicle duct of Triops cancriformis shows that the follicular ducts are lined by a single-layered epithelium which also produces the eggshell material. The cytoplasm is rich in rough endoplasmic reticulum that synthesizes the eggshell material which subsequently aggregates into preformed vacuoles. Newly formed spheres of eggshell material are then excreted into the lumen. At the end of vitellogenesis the oocytes descend toward the longitudinal oviduct and pass through the eggshell material which fills the follicle ducts. The production of the eggshell and its chemical composition in some Phyllopoda are compared. The paper discusses the relationship between the eggshell construction and the reproductive biology of the population.     

Sex-reversed XY females with campomelic dysplasia are H-Y negative

Summary Three families with infants affected with campomelic dysplasia, a genetically determined mesenchymal disease frequently associated with sex reversal were studied. Two XY famales with ovarian gonadal differentiation and typical clinical features of campomelic dysplasia could be tested for H-Y antigen and were found to be H-Y negative.     

Diarylpropanes from Iryanthera coriacea

The trunk wood of Iryanthera coriacea Ducke (Myristicaceae) contains six compounds which belong to the recently discovered 1,3-diarylpropane type of flavonoids, 1-(2-hydroxy-4-methoxyphenyl)-3-(3,4-methylenedioxyphenyl)-propane, 1-(2,4-dihydroxyphenyl)-3-(3,4-methylenedioxyphenyl)-propane, 1-(4-methoxyphenyl)-3-(2-hydroxy-4,5-methylenedioxyphenyl)-propane, 1-(4-hydroxy-2-methoxy-phenyl)-3-(4-hydroxy-3-methoxyphenyl)-propane, 1-(2,4-dihydroxyphenyl)-3-(2-methoxy-4,5-methylene-dioxyphenyl)-propane, 1-(2,4-dihydroxy-3,5-methylphenyl)-3-(2-hydroxy-4,5-methylenedioxyphenyl)-propane.     

Structural analysis of subterranean organs in Zingiberaceae

Xylem structural characteristics are rarely used to separate tribes. This study aims to characterize the morphology of subterranean organs and determine both the occurrence and distribution of the vessel elements in ten species, belonging to Alpinieae and Zingibereae tribes. Species were from protected areas in the Brazilian Atlantic Rain Forest or from private cultivation areas. Roots and rhizomes processing followed both light and scanning electron microscopy procedures. According to morphological and anatomical characteristics, Euclidean distances among taxa were calculated, resulting in a dendrogram based on the unweighted pair group method with arithmetic mean (UPGMA) clustering. Despite our results indicating a similarity among all the species studied, they could be segregated by using qualitative and special metabolites characters in both the rhizome and the root. Vessel elements were found to be confined to the roots, presenting several basal characters in most of species, except for Alpinia purpurata and Etlingera species.     

Reaction between mammalian amine oxidases and their antibodies

Antibodies have been raised against purified beef plasma, pig plasma and pig kidney amine oxidases. Despite the overall similarity, no immunological cross-reactivity was observed among these enzymes, even using a very sensitive light-scattering technique. The presence of substrate affects the rate of the reaction between kidney diamine oxidase and its antibody, but not that of other amine oxidases.