Histochemical and quantitative study of the cloacal glands of Triturus marmoratus marmoratus (Amphibia: Salamandridae)

The cloacal glands of the male marbled newt Triturus marmoratus marmoratus were studied during winter and summer by histochemical and quantitative histologic methods. Four types of glands were distinguished: pelvic, dorsal, ventral, and Kingsbury's glands. The pelvic and dorsal glands have an eosinophilic epithelium and secrete neutral mucins. The ventral and Kingsbury's glands have a basophilic epithelium and secrete acid mucins. The lectin-histochemical characterization of the carbohydrates secreted by the four gland types revealed that the secretion of both the pelvic and Kingsbury's glands contain β-GalNAc in the peripheral region of the oligosaccharide, and that the dorsal glands secrete a glycoprotein with α-GalNAc. The ventral gland sections did not react to any of the lectins used here. The quantitative study revealed that the cloaca undergoes seasonal variations in volume, being significantly larger in winter than in summer. The total volume occupied by both the pelvic and ventral glands, as well as their tubular diameter, are also significantly greater in winter, while these parameters do not vary in dorsal and Kingsbury's glands. No seasonal differences were observed in the height of the epithelium in any gland     

Sesquiterpene lactones of artemisia klotzchiana

Six sesquiterpene lactones and two flavones were isolated and characterized from Artemisia klotzchiana. These included chrysartemin A, matricarin, desacetyl matricarin, ridentin, hanphyllin, jaceosidin, sudatichin and the new guaianolide chloroklotzchin, which is a halogenated lactone. The X-ray structure of hanphyllin is reported.     

Aflatoxin-producing potential of Aspergillus flavus strains isolated from Spanish poultry feeds

A total of 126 fungal strains belonging to the Aspergillus flavus group isolated from commercial poultry mixed feeds were studied. One hundred and twenty-five were identified as A. flavus and one as A. parasiticus. Forty nine strains (39%) produced aflatoxins on a crushed moist wheat medium (28 °C/10 days), whereas only sixteen (13%) showed specific fluorescence on Aflatoxin-Producing Ability Medium. In both media, mainly aflatoxins B₁ and B₂ were detected, the average concentration of aflatoxins being 4294+/–1083 g/kg in crushed moist wheat medium, and 877+/–257 g/kg in Aflatoxin-Producing Ability Medium.     

Minimal moisture content for growth and aflatoxin production by Aspergillus parasiticus in mixed feeds

Minimal moisture content for growth and aflatoxin production by Aspergillus parasiticus in mixed feeds was studied. Minimal moisture content for growth is 16.51%+/–0.45. Very low amounts of aflatoxins are accumulated at days 1 or 2 after the growth started when the initial moisture content of the mixed feed was 17% or lower; on the other hand, significant amounts of aflatoxin are detected when it was 18% or higher.     

Eudesmane triols from Verbesina virgata

Chemical study of Verbesina virgata collected in several localities afforded two eudesmane triols as 4-cinnamates. Their structures were determined by chemical and spectroscopic means. The structure and stereochemistry of one of the triols was confirmed by X-ray crystallography.     

Cementum protein 1‐derived peptide (CEMP 1‐p1) modulates hydroxyapatite crystal formation in vitro

A cementum protein 1‐derived peptide (CEMP1‐p1) consisting of 20 amino acids from the CEMP1's N‐terminus region: MGTSSTDSQQAGHRRCSTSN, and its role on the mineralization process in a cell‐free system, was characterized. CEMP1‐p1's physicochemical properties, crystal formation, and hydroxyapatite (HA) nucleation assays were performed. Crystals induced by CEMP1‐p1 were analyzed by scanning electron microscopy, Fourier‐transform infrared spectroscopy‐attenuated total reflectance (FTIR‐ATR), X‐ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), and atomic force microscopy. The results indicate that CEMP1‐p1 lacks secondary structure, forms nanospheres that organize into three‐dimensional structures, possesses affinity to HA, and induces its nucleation. CEMP1‐p1 promotes the formation of spherical structures composed by densely packed prism‐like crystals, which revealed a Ca/P ratio of 1.56, corresponding to HA. FTIR‐ATR showed predominant spectrum peaks that correspond and are characteristic of HA and octacalcium phosphate (OCP). Analysis by XRD indicates that the crystals show planes with a preferential crystalline orientation for HA and for OCP. HRTEM showed interplanar distances that correspond to crystalline planes of HA and OCP. Crystals are composed by superimposed lamellae, which exhibit epitaxial growth, and each layer of the crystals is structured by nanocrystals. This study reveals that CEMP1‐p1 regulates HA crystal formation, somehow mimicking the in vivo process of mineralized tissues bioformation.     

Forecasts of butterfly future richness change in the southwest Mediterranean. The role of sampling effort and non-climatic variables

Journal of Insect Conservation - We estimated the potential impact of Global Warming on the species richness of Iberian butterflies. First, we determined the grid size that maximized the balance...     

Experimental Evolution of an RNA Virus in Wild Birds: Evidence for Host-Dependent Impacts on Population Structure and Competitive Fitness

Within hosts, RNA viruses form populations that are genetically and phenotypically complex. Heterogeneity in RNA virus genomes arises due to error-prone replication and is reduced by stochastic and selective mechanisms that are incompletely understood. Defining how natural selection shapes RNA virus populations is critical because it can inform treatment paradigms and enhance control efforts. We allowed West Nile virus (WNV) to replicate in wild-caught American crows, house sparrows and American robins to assess how natural selection shapes RNA virus populations in ecologically relevant hosts that differ in susceptibility to virus-induced mortality. After five sequential passages in each bird species, we examined the phenotype and population diversity of WNV through fitness competition assays and next generation sequencing. We demonstrate that fitness gains occur in a species-specific manner, with the greatest replicative fitness gains in robin-passaged WNV and the least in WNV passaged in crows. Sequencing data revealed that intrahost WNV populations were strongly influenced by purifying selection and the overall complexity of the viral populations was similar among passaged hosts. However, the selective pressures that control WNV populations seem to be bird species-dependent. Specifically, crow-passaged WNV populations contained the most unique mutations (~1.7× more than sparrows, ~3.4× more than robins) and defective genomes (~1.4× greater than sparrows, ~2.7× greater than robins), but the lowest average mutation frequency (about equal to sparrows, ~2.6× lower than robins). Therefore, our data suggest that WNV replication in the most disease-susceptible bird species is positively associated with virus mutational tolerance, likely via complementation, and negatively associated with the strength of selection. These differences in genetic composition most likely have distinct phenotypic consequences for the virus populations. Taken together, these results reveal important insights into how different hosts may contribute to the emergence of RNA viruses.