Homosexual behavior in male goats is more frequent during breeding season and in bucks isolated from females

Male homosexual behavior is observed in many ruminant species; seasonality and isolation from females may affect the display of male–male sexual behavior. Our objectives were to determine whether: 1) homosexual behavior has a seasonal pattern in male goats (Capra hircus); 2) isolation from female goats influences the frequency of the display of homosexual behavior; and 3) the frequency of homosexual behaviors is related to testosterone concentration. Bucks were housed in a pen adjacent to another pen with 3 estrous goats (FC group) or in complete isolation from females (IF group). Homosexual behaviors and testosterone concentrations were recorded in October, December, February and May. Frequencies of penile display and flehmen increased in May and were observed more frequently in the IF than in the FC group. Ano-genital sniffing was more frequent in February and May and was more frequent in IF than in FC bucks. Lateral approaches were more frequent in May, in which period this was more frequently observed in IF bucks. Mount attempts and mounts were only observed in IF bucks. Testosterone concentrations increased from December to February and decreased in May, although they were still greater than in October and December. In May IF bucks had greater testosterone concentrations than FC bucks. Testosterone concentrations were only related to the number of lateral approaches in IF bucks in December. In conclusion, homosexual behavior was more frequent during the late breeding season than during the early and the non-breeding seasons, and in males isolated from females than in males housed near estrous females. Testosterone concentrations appear to be unrelated to homosexual behavior.     

Glycosphingolipids from bovine milk and milk fat globule membranes: a comparative study. Adhesion to enterotoxigenic Escherichia coli strains

Several components of milk fat globule membranes (MFGMs) have been reported to display beneficial health properties and some of them have been implicated in the defense of newborns against pathogens. These observations prompted us to determine the glycosphingolipid content of MFGMs and their interaction with pathogens. A comparative study with whole milk components was also carried out. Milk fat globules and MFGMs were isolated from milk. Gangliosides and neutral glycosphingolipids were obtained from MFGMs and whole milk and their fatty acid contents were determined by gas chromatography-mass spectrometry (GC-MS). MFGMs and whole milk showed similar ganglioside and neutral glycosphingolipid contents, with whole milk having more GM3 and glucosylceramide and less GD3, O-acetyl GD3, O-acetyl GT3, and lactosylceramide. The fatty acid content of gangliosides from both sources showed a similar composition. However, the neutral glycosphingolipid fatty acid content seemed to be quite different. Whole milk had fewer very-long-chain fatty acids (18.1% vs. 46.4% in MFGMs) and more medium-chain and unsaturated C18:1 and C18:2 fatty acids. Milk fat globules, MFGMs, lactosylceramide, and gangliosides GM3 and GD3 were observed to bind enterotoxigenic Escherichia coli strains. Furthermore, bacterial hemagglutination was inhibited by MFGMs and glycosphingolipids.     

Cestode antigens induce a tolerogenic-like phenotype and inhibit LPS inflammatory responses in human dendritic cells

Pathogens have developed strategies to modify Dendritic Cells (DCs) phenotypes and impair their functions in order to create a safer environment for their survival. DCs responses to helminths and their derivatives vary among different studies. Here we show that excretory/secretory products of the cestode Taenia crassiceps (TcES) do not induce the maturation of human DCs judged by a lack of increment in the expression of CD83, HLA-DR, CD80 and CD86 molecules but enhanced the production of IL-10 and positively modulated the expression of the C-type lectin receptor MGL and negatively modulated the expression of DC-SIGN. Additionally, these antigens were capable of down-modulating the inflammatory response induced by LPS in these cells by reducing the expression of the maturation markers and the production of the inflammatory cytokines IL-1β, TNF, IL-12 and IL-6. The effects of TcES upon the DCs responses to LPS were stronger if cells were exposed during their differentiation to the helminth antigens. All together, these findings suggest the ability of TcES to induce the differentiation of human DCs into a tolerogenic-like phenotype and to inhibit the effects of inflammatory stimuli.     

Identification of novel prognostic markers in relapsing localized resectable neuroblastoma

Patients with localized resectable neuroblastoma (NB) generally have an excellent prognosis and can be treated by surgery alone, but approximately 10% of them develop local recurrences or metastatic progression. The known predictive risk factors are important for the identification of localized resectable NB patients at risk of relapse and/or progression, who may benefit from early and aggressive treatment. These factors, however, identify only a subset of patients at risk, and the search for novel prognostic markers is warranted. This review focuses on the recent advances in the identification of new prognostic markers. Recently we addressed the search of novel genetic prognostic markers in a selected cohort of patients with stroma-poor localized resectable NB who underwent disease relapse or progression (group 1) or complete remission (group 2). High-resolution array-comparative genomic hybridization (CGH) DNA copy-number analysis technology was used. Chromosome 1p36.22p36.32 loss and 1q22qter gain, detected almost exclusively in group 1 patients, were significantly associated with poor event-free survival (EFS). Increasing evidence points to anaplastic lymphoma kinase (ALK) as a fundamental oncogene associated with NB. The immunohistochemical analysis of sporadic NB localized resectable primary tumors (stage 1-2) showed a correlation between aberrant ALK level of expression and tumor progression and clinical outcome. Moreover, other factors that might influence the clinical behavior of these tumors will be reviewed.     

Global analysis of serine-threonine protein kinase genes in Neurospora crassa

Serine/threonine (S/T) protein kinases are crucial components of diverse signaling pathways in eukaryotes, including the model filamentous fungus Neurospora crassa. In order to assess the importance of S/T kinases to Neurospora biology, we embarked on a global analysis of 86 S/T kinase genes in Neurospora. We were able to isolate viable mutants for 77 of the 86 kinase genes. Of these, 57% exhibited at least one growth or developmental phenotype, with a relatively large fraction (40%) possessing a defect in more than one trait. S/T kinase knockouts were subjected to chemical screening using a panel of eight chemical treatments, with 25 mutants exhibiting sensitivity or resistance to at least one chemical. This brought the total percentage of S/T mutants with phenotypes in our study to 71%. Mutants lacking apg-1, an S/T kinase required for autophagy in other organisms, possessed the greatest number of phenotypes, with defects in asexual and sexual growth and development and in altered sensitivity to five chemical treatments. We showed that NCU02245/stk-19 is required for chemotropic interactions between female and male cells during mating. Finally, we demonstrated allelism between the S/T kinase gene NCU00406 and velvet (vel), encoding a p21-activated protein kinase (PAK) gene important for asexual and sexual growth and development in Neurospora.     

E‐cadherin determines Caveolin‐1 tumor suppression or metastasis enhancing function in melanoma cells

The role of caveolin‐1 (CAV1) in cancer is highly controversial. CAV1 suppresses genes that favor tumor development, yet also promotes focal adhesion turnover and migration of metastatic cells. How these contrasting observations relate to CAV1 function in vivo is unclear. Our previous studies implicate E‐cadherin in CAV1‐dependent tumor suppression. Here, we use murine melanoma B16F10 cells, with low levels of endogenous CAV1 and E‐cadherin, to unravel how CAV1 affects tumor growth and metastasis and to assess how co‐expression of E‐cadherin modulates CAV1 function in vivo in C57BL/6 mice. We find that overexpression of CAV1 in B16F10 (cav‐1) cells reduces subcutaneous tumor formation, but enhances metastasis relative to control cells. Furthermore, E‐cadherin expression in B16F10 (E‐cad) cells reduces subcutaneous tumor formation and lung metastasis when intravenously injected. Importantly, co‐expression of CAV1 and E‐cadherin in B16F10 (cav‐1/E‐cad) cells abolishes tumor formation, lung metastasis, increased Rac‐1 activity, and cell migration observed with B16F10 (cav‐1) cells. Finally, consistent with the notion that CAV1 participates in switching human melanomas to a more malignant phenotype, elevated levels of CAV1 expression correlated with enhanced migration and Rac‐1 activation in these cells.     

Serum Amyloid P Is a Sialylated Glycoprotein Inhibitor of Influenza A Viruses

Members of the pentraxin family, including PTX3 and serum amyloid P component (SAP), have been reported to play a role in innate host defence against a range of microbial pathogens, yet little is known regarding their antiviral activities. In this study, we demonstrate that human SAP binds to human influenza A virus (IAV) strains and mediates a range of antiviral activities, including inhibition of IAV-induced hemagglutination (HA), neutralization of virus infectivity and inhibition of the enzymatic activity of the viral neuraminidase (NA). Characterization of the anti-IAV activity of SAP after periodate or bacterial sialidase treatment demonstrated that α(2,6)-linked sialic acid residues on the glycosidic moiety of SAP are critical for recognition by the HA of susceptible IAV strains. Other proteins of the innate immune system, namely human surfactant protein A and porcine surfactant protein D, have been reported to express sialylated glycans which facilitate inhibition of particular IAV strains, yet the specific viral determinants for recognition of these inhibitors have not been defined. Herein, we have selected virus mutants in the presence of human SAP and identified specific residues in the receptor-binding pocket of the viral HA which are critical for recognition and therefore susceptibility to the antiviral activities of SAP. Given the widespread expression of α(2,6)-linked sialic acid in the human respiratory tract, we propose that SAP may act as an effective receptor mimic to limit IAV infection of airway epithelial cells.