Red cell peroxide metabolism in diabetes mellitus

In a group of normal controls and in a group of diabetics subdivided for type we evaluated the following red blood cell parameters: superoxide dismutase (SOD), glutathione peroxidase (GSH.Px), catalase (C-ase), glutathione content (GSH) and membrane-protein-sulphydryl groups (P-SH). There was no difference in the enzymatic activities of superoxide dismutase, glutathione peroxidase and catalase in normals and in the diabetics. However, the erythrocyte GSH content as well as membrane P-SH groups discriminate the normals from diabetics and also the diabetics subdivided for type. None of these parameters was related to the erythrocyte filterability considered as a reflection of the red blood cell deformability. These findings reveal that the diabetic red blood cell is less protected from oxidant agents.     

Phylogenetic beta diversity in an upper montane Atlantic Forest along an altitudinal gradient

Plant Ecology - Studying community phylogenies along elevation gradients can inform us about the influences of environmental conditions on the structuring communities, and therefore allow...     

Differences between male and female prostates in terms of physiology,sensitivity to chemicals and pathogenesis—A review in a rodent model

The prostate is a gland that is not exclusively present in males, being also found in females of several mammalian species, including humans. There is evidence that the prostate in both sexes is affected by the same pathologies such as prostatitis, benign alterations and even cancer. In view of the difficulties of manipulating the prostate gland, the Mongolian gerbil (Meriones unguiculatus), a rodent species with high incidence of functional prostates in females, is widely used in studies of the female prostate. However, despite knowing much about the similarities between the female and male prostate, little emphasis has been placed on the differences between them. This review investigates the intersex differences in prostate development, physiology and pathogenesis. The female prostate develops earlier than in males and studies indicate that it is more sensitive to oestrogens than the male prostate, as well as being more sensitive to exposure to xenoestrogens, such as Bisphenol A and methylparaben, with a higher susceptibility to benign lesions in the adult and senile prostate than in males. In addition, the female prostate is impacted by pregnancy and the oestrous cycle, and is also dependent on progesterone. The peculiarities of the female prostate raise concerns about the risk of it undergoing neglected changes as a result of environmental chemicals, since safe dosages are established exclusively for the male prostate.     

Hydrophobic Derivatives of Glycopeptide Antibiotics as Inhibitors of Protein Kinases

As key regulators of cell signaling, protein kinases (PKs) are attractive targets for therapeutic intervention in a variety of diseases. Herein, we report for the first time the inhibitory activity of polycyclic peptides, particularly, derivatives of glycopeptide antibiotics teicoplanin and eremomycin, against a panel of 12 recombinant human protein kinases and two protein kinases (CK1 and CK2) isolated from rat liver. Several of the investigated compounds inhibited various PKs with IC₅₀ values below 10 μM and caused >90% suppression of the enzyme activity at 10 μM concentration. Kinetic analysis of the protein kinase CK2α inhibition by the teicoplanin aglycon analogue (7) demonstrated the non-competitive mechanism of inhibition (with regard to ATP). Interestingly, the inhibitory activity of some investigated compounds correlated with the earlier described antiviral activity against HIV, HCV, and other corona- and flaviviruses.     

The effect of the glyphosate, 2,4-D, atrazine e nicosulfuron herbicides upon the Edaphic collembola (Arthropoda: Ellipura) in a no tillage system

The use of herbicides is a common and intensive practice in no tillage systems. The herbicides can influence, directly or indirectly, the population of edaphic arthropods. Collembola is a group that functions as a bio-indicator of soil conditions. The degree of abundance and diversity of Collembola provides the level of soil disturbance provoked by agricultural practices. This experiment was designed to compare the influence of herbicides on the population fluctuation of Collembola in a no-till soil preparation system. The work was conducted in a non irrigated no-till area at the Núcleo Experimental de Ciências Agrárias of the Universidade Federal de Mato Grosso do Sul (UFMS), Campus de Dourados, in soil planted with corn as a surface covering, during the period of December, 2002 to December, 2003. The data were analyzed according to a completely randomized model, in a split plot design. The plots received four types of herbicides: glyphosate, atrazine, 2,4-D and nicosulfuron. A fifth plot did not receive any herbicide (control), for a total of five treatment types. The sub plots were represented by their collection times (10, 20, 30 and 40 days after the herbicide applications). Both the type of herbicide and the time of data sampling influenced the Collembola population fluctuaction. The treatments with atrazine and 2,4-D caused the most reduction of the population of Collembola, depending on the time of application.     

Population dynamics of Aceria guerreronis (Acari: Eriophyidae) and other mites associated with coconut fruits in Una, state of Bahia, northeastern Brazil

Aceria guerreronis Keifer is a major coconut pest in the Americas, Africa and some Asian countries, and occurs in high population levels in northeastern Brazil. The determination of the climatic conditions that favorably affect its population growth and the prevalence and abundance of predatory mites can promote more efficient control practices. Our objective was to evaluate the pattern of occurrence and population dynamics of A. guerreronis, their associated predators and other mites during a 2?year period in a hybrid coconut plantation in the municipality of Una, state of Bahia, northeastern Brazil. Monthly samples of fruits were taken from June 2008 to May 2010 for qualitative and quantitative evaluation of mites. Aceria guerreronis represented 99.9?% of the mites. An average density of 1,117 mites per fruit and a maximum of 23,596 mites per fruit indicated that the level of infestation can be high in Bahia. Bdella ueckermanni Hernandes, Daud and Feres was the most abundant and frequent predator. Population increase of A. guerreronis was directly related to the temperature rise and inversely related to both the increase of air relative humidity and rainfall. The highest population densities occurred from November to March. The largest A. guerreronis populations occurred in fruits with 32 and 48?% of damaged surface. The relationship between prevailing wind direction and incidence of A. guerreronis could not be corroborated or refuted.     

Desmin filaments are stably associated with the outer nuclear surface in chick myoblasts

Eukaryotic cells have highly organized, interconnected intracellular compartments. The nuclear surface and cytoplasmic cytoskeletal filaments represent compartments involved in such an association. Intermediate filaments are the major cytoskeletal elements in this association. Desmin is a muscle-specific structural protein and one of the earliest known muscle-specific genes to be expressed during cardiac and skeletal muscle development. Desmin filaments have been shown to be associated with the nuclear surface in the myogenic cell line C2C12. Previous studies have revealed that mice lacking desmin develop imperfect muscle, exhibiting the loss of nuclear shape and positioning. In the present work, we have analyzed the association between desmin filaments and the outer nuclear surface in nuclei isolated from pectoral skeletal muscle of chick embryos and in primary chick myogenic cell cultures by using immunofluorescence microscopy, negative staining, immunogold, and transmission electron microscopy. We show that desmin filaments remain firmly attached to the outer nuclear surface after the isolation of nuclei. Furthermore, positive localization of desmin persists after gentle washing of the nuclei with high ionic strength solutions. These data suggest that desmin intermediate filaments are stably and firmly connected to the outer nuclear surface in skeletal muscles cells in vivo and in vitro.