Species composition,similarity, and structure of mayan homegardens in tixpeual and tixcacaltuyub,yucatan, Mexico

We studied species composition, similarity, and structure of homegardens in two Yucatecan Maya communities, Tixpeual and Tixcacaltuyub, Yucatan, Mexico. The number of gardens sampled per village was 20 and 22; total area sampled was very similar, 45,265 m² and 40,150 m²; the number of trees and shrubs present was 5651 and 5603; and number of species was 135 and 133, respectively. Diversity was low for both sites (H′= 1.6), as were the correlation coefficients (r) for the species-area and individuals-area correlations. The relatively low values obtained for the structural parameters reflect the random pattern of plant incorporation to the gardens, the variability in the proportion of constantly used and not constantly used garden area, and a certain uniformity in the number of species used and number of individuals present, and the relationship between these parameters and garden size. All these reflect the uniqueness of each homegarden, which depends upon the cultural background of the owner. We noticed a trend towards a change in homegarden structure and function in response to the modernization process. Homegardens in villages in the outskirts of cities tend to have more ornamental species and commercial fruit plants than homegardens in isolated villages.     

Structure-toxicity relationship of aminoglycosides: correlation of 2'-amine basicity with acute toxicity in pseudo-disaccharide scaffolds

A new pseudo-disaccharide NB23 with a 3',4'-methylidene protection was designed and its properties were evaluated in comparison to other two structurally related pseudo-disaccharides. The basicity of the 2'-amine was found to be well correlated to acute toxicity data in mice: the increase in the basicity is associated with the toxicity increase. Based on these data, a new pseudo-trisaccharide NB45 was constructed. NB45 exhibited significant antibacterial activity while at the same time retained low acute toxicity.     

Bcl-2 proteins link programmed cell death with growth and morphogenetic adaptations in the fungal plant pathogen Colletotrichum gloeosporioides

Proteins belonging to the Bcl-2 family regulate apoptosis in mammals by controlling mitochondria efflux of cytochrome c and other apoptosis-related proteins. Homologues of human Bcl-2 proteins are found in different metazoan organisms where they play a similar role, while they seem to be absent in plants and fungi. Nonetheless, Bcl-2 protein members can induce or prevent yeast cell death, suggesting that enough functional conservation exists between apoptotic machineries of mammals and fungi. Here we show that induction or prevention of apoptosis by Bcl-2 proteins in the fungal plant pathogen Colletotrichum gloeosporioides is tightly linked with growth and morphogenetic adaptation that occur throughout the entire fungal life cycle. Isolates expressing the pro-apoptotic Bax protein underwent cell death with apoptotic characteristics, and showed alterations in conidial germination that are associated with pathogenic and non-pathogenic life styles. Isolates expressing the anti-apoptotic Bcl-2 protein had prolonged longevity, were protected from Bax-induced cell death, and exhibited enhanced stress resistance. These isolates also had enhanced mycelium and conidia production, and were hyper virulent to host plants. Our findings show that apoptotic-associated machinery regulates morphogenetic switches, which are critical for proper responses and adaptation fungi to different environments.     

A unique genomic sequence in the Wolf-Hirschhorn syndrome [WHS] region of humans is conserved in the great apes

The Wolf-Hirschhorn syndrome (WHS) is caused by a partial deletion in the short arm of chromosome 4 band 16.3 (4p16.3). A unique-sequence human DNA probe (39 kb) localized within this region has been used to search for sequence homology in the apes' equivalent chromosome 3 by FISH-technique. The WHS loci are conserved in higher primates at the expected position. Nevertheless, a control probe, which detects alphoid sequences of the pericentromeric region of humans, is diverged in chimpanzee, gorilla, and orangutan. The conservation of WHS loci and divergence of DNA alphoid sequences have further added to the controversy concerning human descent.     

Dietary Docosahexaenoic Acid Supplementation Modulates Hippocampal Development in the Pemt?/? Mouse

The development of fetal brain is influenced by nutrients such as docosahexaenoic acid (DHA, 22:6) and choline. Phosphatidylethanolamine-N-methyltransferase (PEMT) catalyzes the biosynthesis of phosphatidylcholine from phosphatidylethanolamine enriched in DHA and many humans have functional genetic polymorphisms in the PEMT gene. Previously, it was reported that Pemt^−/− mice have altered hippocampal development. The present study explores whether abnormal phosphatidylcholine biosynthesis causes altered incorporation of DHA into membranes, thereby influencing brain development, and determines whether supplemental dietary DHA can reverse some of these changes. Pregnant C57BL/6 wild type (WT) and Pemt^−/− mice were fed a control diet, or a diet supplemented with 3 g/kg of DHA, from gestational day 11 to 17. Brains from embryonic day 17 fetuses derived from Pemt^−/− dams fed the control diet had 25–50% less phospholipid-DHA as compared with WT (p < 0.05). Also, they had 60% more neural progenitor cell proliferation (p < 0.05), 60% more neuronal apoptosis (p < 0.01), and 30% less calretinin expression (p < 0.05; a marker of neuronal differentiation) in the hippocampus compared with WT. The DHA-supplemented diet increased fetal brain Pemt^−/− phospholipid-DHA to WT levels, and abrogated the neural progenitor cell proliferation and apoptosis differences. Although this diet did not change proliferation in the WT group, it halved the rate of apoptosis (p < 0.05). In both genotypes, the DHA-supplemented diet increased calretinin expression 2-fold (p < 0.05). These results suggest that the changes in hippocampal development in the Pemt^−/− mouse could be mediated by altered DHA incorporation into membrane phospholipids, and that maternal dietary DHA can influence fetal brain development.     

Deficiency of the Cog8 Subunit in Normal and CDG‐Derived Cells Impairs the Assembly of the COG and Golgi SNARE Complexes

Multiple mutations in different subunits of the tethering complex Conserved Oligomeric Golgi (COG) have been identified as a cause for Congenital Disorders of Glycosylation (CDG) in humans. Yet, the mechanisms by which COG mutations induce the pleiotropic CDG defects have not been fully defined. By detailed analysis of Cog8 deficiency in either HeLa cells or CDG‐derived fibroblasts, we show that Cog8 is required for the assembly of both the COG complex and the Golgi Stx5‐GS28‐Ykt6‐GS15 and Stx6‐Stx16‐Vti1a‐VAMP4 SNARE complexes. The assembly of these SNARE complexes is also impaired in cells derived from a Cog7‐deficient CDG patient. Likewise, the integrity of the COG complex is also impaired in Cog1‐, Cog4‐ and Cog6‐depleted cells. Significantly, deficiency of Cog1, Cog4, Cog6 or Cog8 distinctly influences the production of COG subcomplexes and their Golgi targeting. These results shed light on the structural organization of the COG complex and its subcellular localization, and suggest that its integrity is required for both tethering of transport vesicles to the Golgi apparatus and the assembly of Golgi SNARE complexes. We propose that these two key functions are generally and mechanistically impaired in COG‐associated CDG patients, thereby exerting severe pleiotropic defects.     

Evolution of trichomes and its systematic significance in Salvia (Mentheae; Nepetoideae; Lamiaceae)

We have investigated the trichome characteristics in representative species of Salvia and Pleudia in order to evaluate this source of morphological evidence for addressing problems regarding generic delimitation and subgeneric classification. Trichomes of 46 Salvia spp., representing three subgenera in Iran, were investigated using light microscopy and scanning electron microscopy. General trichome characteristics were constant among different populations of a certain species, but showed a degree of variability useful in the delimitation of taxa, specifically at lower taxonomic levels. Trichome characters of taxonomic interest are as follows: types of glandular hair; number of composing cells (uni‐, bi‐ or multicellular); size and thickness; branching pattern; and presence of papillae on the surface. Non‐glandular trichomes can be simple and branched. Glandular trichomes can be stalked, subsessile or sessile. Our investigation reveals the usefulness of such characters in providing fundamental taxonomic criteria for taxon delimitation in these genera at various levels, especially at the specific rank. Furthermore, the data presented here indicate the potential applicability of such characters in the determination of evolutionary trends in Salvia and allies. © 2015 The Linnean Society of London, Botanical Journal of the Linnean Society, 2016, 180 , 241–257.     

Leishmania infantum: prime boost vaccination with C-terminal extension of cysteine proteinase type I displays both type 1 and 2 immune signatures in BALB/c mice

The aims of current study are to describe the immunogenicity and protective efficacy of prime boost vaccine using C-terminal extension (CTE) of cysteine proteinase type I of Leishmania infantum in BALB/c mice. Group I as vaccinated group primed with 100 microg of pcDNA-CTE and 3 weeks later boosted with combination of 30 microg rCTE, 50 microg of CpG and Montanide 720. Groups II and III were served as control groups. Although, this vaccination regimen did not protect mice against the infectious challenge but it was highly immunogenic. IgG2a has been raised strongly against rCTE in contrast to IgG1 and remains high at every time point under study. By analysis of CTE synthetic peptides (CTE100) before challenge, both IgG1 and IgG2a were produced and for all overlapping synthetic peptides (CTE 1-8) IgG1 raised significantly. This statue is changed at 7 weeks after challenge and only CTE2 and CTE3 have shown to induce considerable amount of IgG1. In all groups, the level of IL-5 started to increase with high concentration shortly passing only 3 weeks after infectious challenge. In compare with two control groups, the vaccinated group produced significantly higher level of IL-5 at 7 weeks post-infection. The parasite burden of all groups is similar at 4 weeks post-challenge in both liver and spleen. In contrast, at 8 weeks post challenge, the spleen of the vaccinated group showed significantly higher level of parasite load in compare with two control groups. This study demonstrated that immunization with CTE display both type 1 and 2 immune signatures in experimental murine model of L. infantum infection.