Quality indexes to assess the reliability of genotypes in studies using noninvasive sampling and multiple‐tube approach

In noninvasive studies, the intersample variance in DNA quality and quantity is large, and produces multilocus genotypes of highly variable quality. Here we propose a standardized method for testing the reliability of the genotyping procedure when using the multiple‐tube approach. The quality indexes generated will allow reliable comparisons among samples, loci, studies, and field and/or laboratory protocols. These indexes represent a powerful tool for the quality management of noninvasive studies.     

Why western spruce budworms travel so far for the winter

1. Conifer‐feeding budworms (Choristoneura) hibernate in sheltered locations on their host trees from late summer of 1 year to spring of the next. During this period, they do not feed but rely on sustenance provided in the egg. Overwinter survival is dependent on the rate of consumption of these limited reserves. 2. A process model was developed that quantifies the relationship between the rate of consumption and survival at variable temperatures and exposure times for western spruce budworm. The model supported physiological evidence that warm weather conditions early in the diapause period have a dominant influence on overwinter survival. Output compared favourably with field observations of poorer budworm survival at lower elevations where late‐summer and autumn temperatures were warmer compared to those overwintering at cooler, higher elevations. 3. Field experiments demonstrated these weather‐dependent rates of survival were modulated significantly by the degree of shelter experienced by hibernating budworms. 4. Dissection of whole trees harbouring overwintering western spruce budworms showed a significant portion of the population had travelled a considerable distance from the periphery of the tree canopy where eggs were laid to overwinter successfully on the tree bole where sheltered niches are common. 5. Thus, budworms will travel relatively long distances and risk increased mortality during this dispersal to find adequate shelter to overwinter.     

Diagnosis of mycobacterial infection in acquired immunodeficiency syndrome (AIDS) patients and HIV carriers.

Differences in tuberculosis diagnosis between infected and non-infected HIV patients were described. In Barcelona, tuberculosis is present in 41.6% of 851 patients in whom AIDS was detected between 1981 and the first quarter of 1990. We reviewed the results of the methods used for tuberculosis diagnosis in 270 AIDS patients controlled in our hospital, in whom tuberculosis was detected (33.3%), and we compared these data with the results obtained in HIV carriers with tuberculosis and with tuberculous patients without HIV infection. Statistically significant differences were found between the three groups with respect to sex, age, results of Ziehl-Neelsen stain in pulmonary specimens and skin test reaction; between AIDS patients and the non-HIV infected population differences were observed in tuberculosis site. Positive skin test reaction diminished from tuberculous individuals non-HIV infected (95%), to HIV carriers with tuberculosis (71.8%) and AIDS patients with tuberculosis (21.8%). Acid-fast smears from pulmonary specimens were positive in 35.7%, 23.5% and 43.7% respectively. Statistically significant differences were found in tuberculosis localization between tuberculous patients non-HIV infected and tuberculous patients with AIDS, in the last group tuberculosis lymphadenitis was the most frequent localization (33.3%) of extrapulmonary tuberculosis, followed by abdominal tuberculosis (15.5%). The incidence of HIV infection among tuberculous patients was 4.6 in our study, but could be higher if patients between 19 and 30 years old were always checked for anti-HIV antibodies.     

A family of protein-deglutamylating enzymes associated with neurodegeneration

Polyglutamylation is a posttranslational modification that generates glutamate side chains on tubulins and?other proteins. Although this modification has been shown to be reversible, little is known about the enzymes catalyzing deglutamylation. Here we describe the enzymatic mechanism of protein deglutamylation by members of the cytosolic carboxypeptidase (CCP) family. Three enzymes (CCP1, CCP4, and CCP6) catalyze the shortening of polyglutamate chains and a fourth (CCP5) specifically removes the?branching point glutamates. In addition, CCP1, CCP4, and CCP6 also remove gene-encoded glutamates from the carboxyl termini of proteins. Accordingly, we show that these enzymes convert detyrosinated tubulin into Δ2-tubulin and also modify other substrates, including myosin light chain kinase 1. We further analyze Purkinje cell degeneration (pcd) mice that lack functional CCP1 and show that microtubule hyperglutamylation is directly linked to neurodegeneration. Taken together, our results reveal that controlling the length of the polyglutamate side chains on tubulin is critical for neuronal survival.     

Soil phosphorus and disturbance influence liana communities in a subtropical montane forest

Questions: What are the effects of soil, topography, treefall gaps, tree species composition, and tree density on liana species composition and total liana abundance? Location: A 6‐ha permanent plot in a subtropical montane forest in northwest Argentina. Methods: Multiple regressions were used to quantify associations of liana species composition and total liana abundance with edaphic, disturbance and tree community variables. Gradients in liana and tree species composition were quantified using principal components analysis (PCA). Results: Liana species composition was correlated most strongly with soil phosphorus concentration (R²=0.55). Total liana aanased with phosphorus and the density of recent treefall gaps (R²=0.60). Conclusions: In our study area, liana composition and abundance are most strongly correlated with features of the physical environment, rather than host tree characteristics. Our results support the hypothesis that recent increases in liana abundance in mature tropical forests may be related to increased rates of gap formation.     

Improved therapeutic responses for liposomal doxorubicin targeted via thrombospondin peptidomimetics versus untargeted doxorubicin

New therapies in cancer treatment are focusing on multifaceted approaches to starve and kill tumors utilizing both antiangiogenic and chemotherapeutic compounds. In this work, we searched for a peptide vector that would home liposomes both to endothelial and tumor cells. [Abu6]TSPB and [Abu6]TSPA, aspartimide analogs of natural sequences of TSP‐1 and TSP‐2, respectively, were tested for adhesion of tumor and endothelial cells, in vivo and in vitro antiangiogenic effects, and in vivo antitumor action. Both peptides support the adhesion of both types of cells, but only [Abu6]TSPA inhibits the angiogenesis in vivo, and [Abu6]TSPA‐targeted L ‐DOX decreases by 58% (P < 0.008) the HT29 tumor growth in nude mice. The improvement in the doxorubicin antitumor effect should be attributed to the antiangiogenic effect of [Abu6]TSPA, since [Abu6]TSPB, despite being a good ligand for both cell types, had no effect on tumor growth. Copyright © 2010 European Peptide Society and John Wiley & Sons, Ltd.     

Elevated cell-specific microparticles are a biological marker for cerebral dysfunctions in human severe malaria

Cerebral malaria (CM) and severe anemia (SA) are the most severe complications of Plasmodium falciparum infections. Although increased release of endothelial microparticles (MP) correlates with malaria severity, the full extent of vascular cell vesiculation remains unknown. Here, we characterize the pattern of cell-specific MP in patients with severe malaria. We tested the hypothesis that systemic vascular activation contributes to CM by examining origins and levels of plasma MP in relation to clinical syndromes, disease severity and outcome. Patients recruited in Douala, Cameroon, were assigned to clinical groups following WHO criteria. MP quantitation and phenotyping were carried out using cell-specific markers by flow cytometry using antibodies recognizing cell-specific surface markers. Platelet, erythrocytic, endothelial and leukocytic MP levels were elevated in patients with cerebral dysfunctions and returned to normal by discharge. In CM patients, platelet MP were the most abundant and their levels significantly correlated with coma depth and thrombocytopenia. This study shows for the first time a widespread enhancement of vesiculation in the vascular compartment appears to be a feature of CM but not of SA. Our data underpin the role of MP as a biomarker of neurological involvement in severe malaria. Therefore, intervention to block MP production in severe malaria may provide a new therapeutic pathway.