Protective Effects of Selenium and Vitamin E Combination on Experimental Colitis in Blood Plasma and Colon of Rats

Ulcerative colitis increases oxidative damage accompanied by production of free oxygen radicals. Selenium (Se) and vitamin E are two natural antioxidants. The present study was undertaken to investigate the possible protective role of Se and vitamin E combination in experimental colitis induced by acetic acid (AA) in rats. This study was carried out on three groups, namely the first (control), the second (experimental colitis group, 2 ml 5% acetic acid), and the third groups (2 ml 5% acetic acid, vitamin E (100 mg/kg body weight (bw)) plus Se (0.2 mg/kg bw)). The activities of catalase (CAT), prolidase (PRS), myeloperoxidase (MPO), total antioxidant capacity (TAC), total oxidant status (TOS), oxidative stress index (OSI), total thiol (T-SH) were determined in plasma and colon samples. Macroscopic and microscopic damages in colon were increased by AA treatment (p < 0.01 and p < 0.01, respectively), whereas they were decreased by selenium and vitamin E treatment (p < 0.05 and p < 0.01, respectively). The activities of CAT and PRS in the plasma and colon were significantly affected (p < 0.05 and p < 0.01) by treatment of AA, Se, and vitamin E. MPO activity in colon was increased (p < 0.01) by AA treatment and decreased (p < 0.05) by Se and vitamin E administration. The values of TOS and OSI in plasma were increased (p < 0.5) by AA. The TAC and T-SH in colon were decreased (p < 0.05) by AA and increased (p < 0.05) by Se and vitamin E. Based upon these results, Se and vitamin E may play an important role in preventive indication of the oxidative damage associated by acetic acid caused inflammation.     

Microbial communities and chemical changes during fermentation of sugary Brazilian kefir

The microorganisms associated with sugary Brazilian kefir beverage were investigated using a combination of culture-dependent and -independent methods. A total of 289 bacteria and 129 yeasts were identified via phenotypic and genotypic methods. Lb. paracasei (23.8%) was the major bacterial isolate identified, followed by Acetobacter lovaniensis (16.31%), Lactobacillus parabuchneri (11.71%), Lactobacillus kefir (10.03%) and Lactococcus lactis (10.03%). Saccharomyces cerevisiae (54.26%) and Kluyveromyces lactis (20.15%) were the most common yeast species isolated. Scanning electron microscopy showed that the microbiota was dominated by lemon-shaped yeast cells growing in close association with Lactobacillus (long and curved). Some lactic acid bacteria detected by sequence analysis of DGGE (denaturing gradient gel electrophoresis) bands were not recovered at any time through fermentation by plating. Conversely, DGGE fingerprints did not reveal bands corresponding to some of the species isolated by culturing methods. The bacteria Acetobacter lovaniensis and the yeast Kazachstania aerobia are described for the first time in sugary kefir. During the 24 h of fermentation, the concentration of lactic acid ranged from 0.2 to 1.80 mg/ml, and that of acetic acid increased from 0.08 to 1.12 mg/ml. The production of ethanol was limited, reaching a final mean value of 1.24 mg/ml.     

Characterization of the glucose-6-phosphate isomerase (GPI) gene from the halotolerant alga <Emphasis Type="Italic">Dunaliella salina</Emphasis>

Although glucose-6-phosphate isomerase (GPI) plays an important role in glycolysis of both the prokaryotes and eukaryotes, studies on the GPI have not been involved in the halotolerant, unicellular green alga Dunaliella salina (D. salina). In this study, a 2,338 bp of full-length cDNA cloned using rapid amplification of cDNA end (RACE) technique contained an open reading frame (ORF) of 1,980 bp encoding 660 amino acids, which has a predicted molecular weight of 73.3 kD and pI of 6.22 and shares high homology with other organisms. The cloned full-length cDNA was heterologously expressed in Escherichia coli and the recombinant GPI proteins purified using Ni-NTA His Bind column were consistent with the anticipated size of ~75 kD. Predicted 2D and 3D structures of GPI proteins possessed potential active motifs including “GEPGTNGQHSFYQLIHQG” and “VQGFIWGINSFDQWGVELGK”, and critical active site residues, such as Ser 241, Ser 296, Thr 298, Thr 301, Arg 358, Glu 444, His 475 and Lys 600. Real time quantitative RT-PCR demonstrated that the expression level of the GPI gene from D. salina (DsGPI) was induced by 3.5 M NaCl with 14-fold higher than that by 1.5 M NaCl (P < 0.01), but inhibited by the light with 4-fold lower than that in the dark (P < 0.05). It is concluded that the cloned GPI gene is indeed from D. salina and may respond to salt and light.     

A revision of the South American genus <Emphasis Type="Italic">Apuleia</Emphasis> (Leguminosae,Cassieae)

Apuleia Mart., a genus of the Leguminosae native to South America, is revised. Species limits within the genus were tested using morphometrics and shape analysis of leaflets and fruits. Morphological evidence indicates that although there is great variation in Apuleia, the genus cannot be reliably separated into different species or infraspecific taxa. Apuleia is monospecific, comprising the single species A. leiocarpa (Vogel) J. F. Macbr.     

Yellow-necked mice (<Emphasis Type="Italic">Apodemus flavicollis</Emphasis>) and bank voles (<Emphasis Type="Italic">Myodes glareolus</Emphasis>) as zoomonitors of environmental contamination at a polluted area in Slovakia

Background  

Free-living wild rodents are often used as zoomonitors of environmental contamination. In the present study, accumulation of cadmium (Cd), copper (Cu), iron (Fe), and zinc (Zn) in critical organs of yellow-necked mice (Apodemus flavicollis) and bank voles (Myodes glareolus) trapped in a polluted area in Nováky, Slovakia was investigated.     

Inhibitory effects of xenocoumacin 1 on the different stages of <Emphasis Type="Italic">Phytophthora capsici</Emphasis> and its control effect on Phytophthora blight of pepper

Phytophthora species cause enormous economic loss every year worldwide. Xenocoumacin 1 (Xcn1), isolated from the bacterium Xenorhabdus nematophilus, is a broad-spectrum antibiotic against agricultural pathogens, especially Phytophthora. To understand the inhibitory mode of Xcn1 toward Phytophthora pathogens, we determined the inhibitory effects of Xcn1 on Phytophthora capsici both in vitro and in vivo. In vitro, Xcn1 inhibited different stages in the life cycle of P. capsici, including sporangium formation, zoospore germination, and mycelial growth, with 50% effective concentration (EC₅₀) values of 0.037, 0.81, and 2.44 μg ml^?1, respectively. Xcn1 also reduced zoospore motility. In vivo, Xcn1 efficiently controlled the Phytophthora blight of pepper with a disease reduction of 99% at a concentration of 5 μg ml^?1 assessed on the third day after incubation of wound stem plants. In addition, Xcn1-treated P. capsici mycelia exhibited increased mycelial branch spacing, evident plasmolysis, and leakage of intracellular components. In conclusion, in the presence of Xcn1, several stages in the life cycle of P. capsici were inhibited, and the hyphae exhibited obvious morphological changes.     

Alien terrestrial mammals in Brazil: current status and management

The invasion of alien species is an important cause of biodiversity loss worldwide, and many mammals are considered successful invaders outside their former range, with recognized detrimental effects to native ecosystems. Our aim was to review the current literature on alien mammals that have established feral populations in Brazil and to systematize the existing knowledge. Furthermore, we evaluated the current distributions of all invasion mammals and discuss different management actions, including eradication techniques for island populations. We found 17 species of alien mammals living in the wild in Brazil. Based on the current literature and databases regarding invasive species, Lepus europaeus and Sus scrofa had the largest distributions in the Brazilian territory and seem to continue expanding their geographic distributions. Feral dogs and cats were the main alien predators threatening wildlife conservation, especially in protected areas. Further, we call attention to the invasion of Bubalus bubalis, a large species that currently thrives in isolated populations but seems to be quickly expanding its distribution. In conclusion, alien mammals are widespread in Southern and Southeastern Brazil, but at least four ungulate species (Indian sambar, horse, goat, and axis deer) still have small and isolated populations. Finally, future efforts need to evaluate the impacts of alien mammals in Brazil and techniques for their control.     

Effects of landscape features on gene flow of valley oaks (<Emphasis Type="Italic">Quercus lobata</Emphasis>)

Landscape features affect habitat connectivity and patterns of gene flow and hence influence genetic structure among populations. We studied valley oak (Quercus lobata), a threatened species of California (USA) savannas and oak woodlands, with a distribution forming a ring around the Central Valley grasslands. Our main goal was to determine the role of topography and land cover on patterns of gene flow and to test whether elevation or land cover forms stronger barriers to gene flow among valley oak populations. We sampled valley oaks in 12 populations across the range of this species, genotyped each tree at eight nuclear microsatellite loci, and created a series of resistance surfaces by assigning different resistance values to land cover type and elevation. We also estimated recent migration rates and evaluated them with regard to landscape features. There was a significant but weak relationship between Euclidian distance and genetic distance. There was no relationship between genetic distances and land cover, but a significant relationship between genetic distances and elevation resistance. We conclude that gene flow is restricted by high elevations in the northern part of the valley oak range and by high elevations and the Central Valley further south. Migration rate analysis indicated some gene flow occurring east–west but we suggest that the high connectivity in the northern Central Valley is facilitating the formation of these links. We predict that southern populations may become more differentiated in the future through genetic isolation and local adaptation taking place in the face of climate change.     

Cytogenetic effect of prolonged in vitro exposure of <Emphasis Type="Italic">Allium cepa</Emphasis> L. root meristem cells to salt stress

Salt stress severely affects plant growth and regulation; however knowledge about its effect on cytological changes is limited. In this report, studies were carried out to reveal the morphological and cytogenetic responses of the Allium cepa roots after prolonged (7, 14, 20 days) exposure to salt stress in tissue culture conditions. Roots of plants were treated with different concentrations (100, 200, 300 mM) of NaCl and KCl added to the culture medium. Both salts caused root growth reduction and showed cytotoxic effect reflected in reduction of root tip cells mitotic activity and increase of different abnormalities such as chromosome breaks and bridges and formation of micronuclei. This experiment showed differences of the action of excessive amounts of both tested salts at the cellular level, as KCl induced higher frequencies of abnormalities during cell divisions, whereas NaCl showed more mitodepressive effect and more frequently led to the root meristem cell death.