Clinical Profiles and Factors Associated with Death in Adults with Dengue Admitted to Intensive Care Units,Minas Gerais,Brazil

The purpose of our study was to describe the clinical profile of dengue-infected patients admitted to Brazilian intensive care units (ICU) and evaluate factors associated with death. A longitudinal, multicenter case series study was conducted with laboratory-confirmed dengue patients admitted to nine Brazilian ICUs situated in Minas Gerais state, southeastern Brazil from January 1, 2008, to December 31, 2013. Demographic, clinical and laboratory data; disease severity scores; and mortality were evaluated. A total of 97 patients were studied. The in-ICU and in-hospital mortality rates were 18.6% and 19.6%, respectively. Patients classified as having severe dengue according to current World Health Organization classifications showed an increased risk of death in a univariate analysis. Nonsurvivors were older, exhibited lower serum albumin concentrations and higher total leukocyte counts and serum creatinine levels. Other risk factors (vomiting, lethargy/restlessness, dyspnea/respiratory distress) were also associated with death in a univariate analysis. Multivariate analysis indicated that in-hospital mortality was significantly associated with Acute Physiology and Chronic Health Evaluation II and the Sequential Organ Failure Assessment score. The ICU and in-hospital mortality observed in this study were higher than values reported in similar studies. An increased frequency of ICU admission due to severe organ dysfunction, higher severity indices and scarcity of ICU beds may partially explain the higher mortality.     

Effect of trehalose on a phospholipid membrane under mechanical stress

Explicit solvent molecular dynamics simulations were used to investigate at atomic resolution the effect of trehalose on a hydrated phospholipid bilayer under mechanical stress (stretching forces imposed in the form of negative lateral pressure). Simulations were performed in the absence or presence of trehalose at 325 K, and with different values for negative lateral pressure. In the concentration regime (2 molal) and range of lateral pressures (1 to −250 bar) investigated, trehalose was found to interact directly with the membrane, partially replacing water molecules in the formation of hydrogen bonds with the lipid headgroups. Similar to previous findings in the context of thermal stress, the number, degree of bridging, and reaching depth of these hydrogen bonds increased with the magnitude of perturbation. However, at the concentration considered, trehalose was not sufficient to preserve the integrity of the membrane structure and to prevent its extreme elongation (and possible disruption) under the effect of stretching forces.     

Comparative analysis of rice MADS-box genes expressed during flower development

MADS-box genes involved in flower development have been isolated and studied in a wide variety of plant species. However, most of these studies are related to dicot species like Antirrhinum majus, Arabidopsis thaliana and Petunia hybrida. Although the floral structures of typical monocot and dicot flowers differ substantially, previous studies indicate that MADS-box genes controlling floral organ identity in dicots can also be identified in monocot plants like rice and maize. To extend this study further to obtain a more global picture of monocot and dicot MADS-box gene evolution, we performed a phylogenetic study using MADS-box genes from A. thaliana and Oryza sativa. Furthermore, we investigated whether the identified orthologues of Arabidopsis and rice have a conserved expression profile that could indicate conservation of function.     

Robots, pipelines, polyproteins: enabling multiprotein expression in prokaryotic and eukaryotic cells

Multiprotein complexes catalyze vital biological functions in the cell. A paramount objective of the SPINE2 project was to address the structural molecular biology of these multiprotein complexes, by enlisting and developing enabling technologies for their study. An emerging key prerequisite for studying complex biological specimens is their recombinant overproduction. Novel reagents and streamlined protocols for rapidly assembling co-expression constructs for this purpose have been designed and validated. The high-throughput pipeline implemented at IGBMC Strasbourg and the ACEMBL platform at the EMBL Grenoble utilize recombinant overexpression systems for heterologous expression of proteins and their complexes. Extension of the ACEMBL platform technology to include eukaryotic hosts such as insect and mammalian cells has been achieved. Efficient production of large multicomponent protein complexes for structural studies using the baculovirus/insect cell system can be hampered by a stoichiometric imbalance of the subunits produced. A polyprotein strategy has been developed to overcome this bottleneck and has been successfully implemented in our MultiBac baculovirus expression system for producing multiprotein complexes.     

A study to sustain the hypothesis of the multiple genesis of oligoasthenoteratospermia in human idiopathic infertile males

Interdependence between sperm concentration, motility, morphology, and the percentage of aneuploid sperm was explored to test whether oligoasthenoteratospermia (OAT) may have a multiple origin in idiopathic infertile males. A total of 174 men (age, 35.8 +/- 4.3 yr) with idiopathic infertility were studied. Seven patients had nonobstructive azoospermia, 55 had severe OAT, 30 had OAT, 27 had isolated alterations of motility, 45 had alterations of morphology and of motility, and 10 had isolated alterations of morphology. The sperm morphology was assessed with strict criteria. The percentage of aneuploid sperm was assessed with fluorescent in situ hybridization for chromosomes X, Y, 13, 15, 16, 17, 18, 21, and 22. Relationships between sperm features, and the relationship between sperm features and aneuploidies were analyzed with multivariate regression analysis. Statistical analysis did not find any significant relationship between the percentage of typical forms and sperm concentration or between morphology and motility. On the other hand, a positive and significant relationship was found between sperm concentration and motility. The percentage of aneuploid sperm was inversely and significantly related to the percentage of typical forms but not to motility and concentration. Sperm morphology is an independent characteristic with respect to concentration and motility, whereas it showed a significant inverse relationship with respect to the percentage of aneuploid sperm. This means that idiopathic OAT may occur by means of at least two independent pathways, the first affecting concentration and/or motility and the second affecting morphology.     

Large and dissimilar repertoire of Melan-A/MART-1-specific CTL in metastatic lesions and blood of a melanoma patient

It is widely accepted that the repertoire of Melan-A-specific T cells naturally selected in melanoma patients is diverse and mostly nonoverlapping among different individuals. To date, however, no studies have addressed the TCR profile in different tumor sites and the peripheral blood from the same patient. We compared the TCR usage of Melan-A-specific T cells from different compartments of a single melanoma patient to evaluate possible clonotype expansion or preferential homing over a 4-mo follow-up period. Using HLA-A2 peptide tetramers, CD8(+) T cells recognizing the modified Melan-A immunodominant ELAGIGILTV peptide were isolated from four metastatic lesions resected from a single melanoma patient, and their TCR repertoire was studied. A panel of T cell clones was generated by cell cloning of tetramer-positive cells. Analysis of the TCR beta-chain V segment and the complementarity-determining region 3 (CDR3) length and sequence revealed a large diversity in the TCR repertoire, with only some of the clones showing a partial conservation in the CDR3. A similar degree of diversity was found by analyzing a number of T cell clones obtained after sorting a Melan-A-specific population derived from PBLs of the same patient after in vitro culture with the immunodominant epitope. Moreover, clonotypes found at one site were not present in another, suggesting the lack of expansion and circulation of one or more clonotypes. Taken together, these results buttress the notion that the CTLs recognizing the immunodominant Ag of Melan-A comprise a high number of different clonotypic TCR, of which only some exhibit common features in the CDR3.     

Differentiation of repetitive DNA sites and sex chromosome systems reveal closely related group in Parodontidae (Actinopterygii: Characiformes)

Parodon and Apareiodon lack sufficiently consistent morphological traits to be considered a monophyletic group in Parodontidae. Species within this family are either sex-homomorphic or sex-heteromorphic (i.e., lacking a differentiated sex chromosome system, ZZ/ZW or ZZ/ZW(1)W(2)). In this study, a DNA fragment from the heterochromatin segment of the W chromosome of Apareiodon ibitiensis (named WAp) was microdissected and used for in situ mapping of nine Parodontidae species. The species were also characterized using a satellite DNA probe (pPh2004). The species were phylogenetically clustered according to 17 characters, which were examined by both classical and molecular cytogenetic techniques. Given the present results, the single ZZ/ZW sex chromosome system seems to have been derived from a paracentric inversion of a terminal WAp site onto the proximal regions of the short arms of a metacentric chromosome pair, followed by WAp site amplification. We reason that these events restrained recombination and favored differentiation of the W chromosome in some species. Moreover, co-hybridization experiments targeting the WAp and pPh2004 repetitive DNA sites of A. affinis suggest that the ZZ/ZW(1)W(2) sex chromosomes of this species may have arisen from a translocation between the proto-sex chromosome and an autosome. Our phylogenetic analysis corroborates the hypothesis of sex chromosome differentiation and establishes groups of closely related species. The phylogenetic reorganization in response to these new data supports the presence of internal monophyletic groups within Parodontidae.     

P2RY1/ALK3-Expressing Cells within the Adult Human Exocrine Pancreas Are BMP-7 Expandable and Exhibit Progenitor-like Characteristics

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