Sexual experience in female mice involves synaptophysin-related plasticity in the accessory olfactory bulb.

Sexually naïve female mice do not display high levels of sexual receptivity in their first sexual experience; they require around 4-5 sexual encounters to display the full receptive response, assessed by the lordosis reflex. In this study, we evaluated if repeated sexual stimulation with the same male is associated with changes in synaptic remodeling evaluated by synaptophysin (SYP) in brain structures involved in the control of sexual behavior such as the main and accessory olfactory bulbs (MOB and AOB, respectively), medial preoptic area (MPOA), ventromedial hypothalamus (VMH), and amygdala (AMG). Female mice were ovariectomized and hormonally primed to induce sexual receptivity. They were randomly distributed into three groups: a) sexually naïve (SN), with no prior sexual stimulation; b) sexually inexperienced (SI), with one prior mating session; and c) sexually experienced (SE), with six mating sessions. The SI group showed a significant decrease in SYP in the glomerular, mitral and granular layers of the AOB in comparison to SN and SE females. SYP expression increased in the SE group in comparison to SN and SI females in the glomerular and mitral cell layers of the AOB. No significant differences between groups were found in the other brain regions (MOB, MPOA, VMH or AMG). These changes in SYP expression in the AOB suggest that plastic modifications in this brain region can be associated with receptivity increase in sexual experience in female mice.

Bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii crops evaluated by metagenomics / Diversidade bacteriana em solos de prados andinos elevados perturbados por culturas de Lepidium meyenii avaliadas por metagenômica

Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.(AU)

A qualidade do solo é normalmente determinada pelas suas características físico-químicas sem ter em conta as comunidades bacterianas que desempenham um papel fundamental na decomposição química dos nutrientes das plantas. Neste contexto, o objetivo do estudo foi avaliar a diversidade bacteriana em solos de prados andinos elevados perturbados pelo cultivo de Lepidium meyenii sob diferentes gradientes de utilização (primeira, segunda e terceira utilizações) e desenvolvimento das culturas (pré-semeadura, desenvolvimento do hipocótilo e pós colheita). A amostragem foi realizada no planalto de Bombón, nos Andes centrais do Peru, durante as estações das chuvas e das águas baixas, pelo método sistemático baseado num padrão específico atribuído em forma geométrica retangular a uma profundidade de 0 - 20 cm. A caracterização das comunidades bacterianas foi realizada através da sequenciação metagenômica do rRNA 16S. Foram relatadas 376 famílias de bactérias, das quais se verificou uma alteração significativa na composição e distribuição bacteriana em relação à pressão de utilização. Não se registaram grandes alterações devido ao desenvolvimento do Lepidium meyenii. As famílias mais sensíveis à utilização de indicadores de pressão e pobreza do solo foram as Verrucomicrobiaceae, Acidobacteraceae e Aakkermansiaceae.(AU)

Bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii crops evaluated by metagenomics / Diversidade bacteriana em solos de prados andinos elevados perturbados por culturas de Lepidium meyenii avaliadas por metagenômica

Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.

A qualidade do solo é normalmente determinada pelas suas características físico-químicas sem ter em conta as comunidades bacterianas que desempenham um papel fundamental na decomposição química dos nutrientes das plantas. Neste contexto, o objetivo do estudo foi avaliar a diversidade bacteriana em solos de prados andinos elevados perturbados pelo cultivo de Lepidium meyenii sob diferentes gradientes de utilização (primeira, segunda e terceira utilizações) e desenvolvimento das culturas (pré-semeadura, desenvolvimento do hipocótilo e póscolheita). A amostragem foi realizada no planalto de Bombón, nos Andes centrais do Peru, durante as estações das chuvas e das águas baixas, pelo método sistemático baseado num padrão específico atribuído em forma geométrica retangular a uma profundidade de 0 - 20 cm. A caracterização das comunidades bacterianas foi realizada através da sequenciação metagenômica do rRNA 16S. Foram relatadas 376 famílias de bactérias, das quais se verificou uma alteração significativa na composição e distribuição bacteriana em relação à pressão de utilização. Não se registaram grandes alterações devido ao desenvolvimento do Lepidium meyenii. As famílias mais sensíveis à utilização de indicadores de pressão e pobreza do solo foram as Verrucomicrobiaceae, Acidobacteraceae e Aakkermansiaceae.

Bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii crops evaluated by metagenomics / Diversidade bacteriana em solos de prados andinos elevados perturbados por culturas de Lepidium meyenii avaliadas por metagenômica

Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.

A qualidade do solo é normalmente determinada pelas suas características físico-químicas sem ter em conta as comunidades bacterianas que desempenham um papel fundamental na decomposição química dos nutrientes das plantas. Neste contexto, o objetivo do estudo foi avaliar a diversidade bacteriana em solos de prados andinos elevados perturbados pelo cultivo de Lepidium meyenii sob diferentes gradientes de utilização (primeira, segunda e terceira utilizações) e desenvolvimento das culturas (pré-semeadura, desenvolvimento do hipocótilo e pós colheita). A amostragem foi realizada no planalto de Bombón, nos Andes centrais do Peru, durante as estações das chuvas e das águas baixas, pelo método sistemático baseado num padrão específico atribuído em forma geométrica retangular a uma profundidade de 0 - 20 cm. A caracterização das comunidades bacterianas foi realizada através da sequenciação metagenômica do rRNA 16S. Foram relatadas 376 famílias de bactérias, das quais se verificou uma alteração significativa na composição e distribuição bacteriana em relação à pressão de utilização. Não se registaram grandes alterações devido ao desenvolvimento do Lepidium meyenii. As famílias mais sensíveis à utilização de indicadores de pressão e pobreza do solo foram as Verrucomicrobiaceae, Acidobacteraceae e Aakkermansiaceae.

Bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii crops evaluated by metagenomics

Abstract Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.

Resumo A qualidade do solo é normalmente determinada pelas suas características físico-químicas sem ter em conta as comunidades bacterianas que desempenham um papel fundamental na decomposição química dos nutrientes das plantas. Neste contexto, o objetivo do estudo foi avaliar a diversidade bacteriana em solos de prados andinos elevados perturbados pelo cultivo de Lepidium meyenii sob diferentes gradientes de utilização (primeira, segunda e terceira utilizações) e desenvolvimento das culturas (pré-semeadura, desenvolvimento do hipocótilo e pós-colheita). A amostragem foi realizada no planalto de Bombón, nos Andes centrais do Peru, durante as estações das chuvas e das águas baixas, pelo método sistemático baseado num padrão específico atribuído em forma geométrica retangular a uma profundidade de 0 - 20 cm. A caracterização das comunidades bacterianas foi realizada através da sequenciação metagenômica do rRNA 16S. Foram relatadas 376 famílias de bactérias, das quais se verificou uma alteração significativa na composição e distribuição bacteriana em relação à pressão de utilização. Não se registaram grandes alterações devido ao desenvolvimento do Lepidium meyenii. As famílias mais sensíveis à utilização de indicadores de pressão e pobreza do solo foram as Verrucomicrobiaceae, Acidobacteraceae e Aakkermansiaceae.

Bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii crops evaluated by metagenomics.

Soil quality is usually determined by its physical-chemical characteristics without taking into account the bacterial communities that play a fundamental role in the chemical decomposition of plant nutrients. In this context, the objective of the study was to evaluate bacterial diversity in high Andean grassland soils disturbed with Lepidium meyenii cultivation under different gradients of use (first, second and third use) and crop development (pre-sowing, hypocotyl development and post-harvest). The sampling was carried out in the Bombón plateau in the central Andes of Peru, during the rainy and low water seasons, by the systematic method based on a specific pattern assigned in a geometric rectangular shape at a depth of 0 - 20 cm. The characterization of the bacterial communities was carried out through the metagenomic sequencing of the 16S rRNA. 376 families of bacteria were reported, of which it was determined that there was a significant change in bacterial composition and distribution in relation to use pressure. There were no major changes due to the development of Lepidium meyenii. The families most sensitive to use pressure and soil poverty indicators were Verrucomicrobiaceae, Acidobacteraceae and Aakkermansiaceae.

Localization of interleukin-6 signaling complex in epithelialized apical lesions of endodontic origin.

OBJECTIVES: We aimed to determine the immunolocalization patterns of the interleukin (IL)-6 signaling complex in epithelialized and non-epithelialized apical lesions of endodontic origin (ALEOs). MATERIALS AND METHODS: Epithelialized (n = 8) and non-epithelialized (n = 7) ALEOs were obtained from teeth with indication of extraction in patients with clinical diagnosis of apical periodontitis. All tissues were subjected to routine processing for histopathologic examination and primary antibodies for IL-6, IL-6 receptor (R), and glycoprotein (gp)-130 were used for immunohistochemistry and double immunofluorescence co-localization. RESULTS: IL-6, IL-6R, and gp-130 were immunolocalized in endothelial cells and mononuclear leukocytes in a diffuse pattern within the connective tissue of epithelialized and non-epithelialized ALEOs. In the epithelialized lesions, two different patterns were identified: IL-6 signaling complex was localized within the proliferating epithelium in a diffuse intracellular pattern and in a cell membrane localization pattern within the mature epithelial lining, showing a decreased intensity towards the surface layers. CONCLUSIONS: IL-6, IL-6R, and gp-130 localized to mononuclear inflammatory cells, vascular endothelial cells, and immature proliferating epithelia in a diffuse pattern and in mature lining epithelia in a localized cell membrane pattern, supporting a role for epithelial proliferation during cyst formation. Additional cell membrane co-localization of IL-6 receptor complex suggests classic signaling involvement in addition to trans-signaling.

Effects of Mating and Social Exposure on Cell Proliferation in the Adult Male Prairie Vole (Microtus ochrogaster).

Microtus ochrogaster is a rodent with a monogamous reproductive strategy characterized by strong pair bond formation after 6 h of mating. Here, we determine whether mating-induced pair bonding increases cell proliferation in the subventricular zone (SVZ), rostral migratory stream (RMS), and dentate gyrus (DG) of the hippocampus in male voles. Males were assigned to one of the four groups: (1) control: males were placed alone in a clean cage; (2) social exposure to a female (SE m/f): males that could see, hear, and smell a sexually receptive female but where physical contact was not possible, because the animals were separated by an acrylic screen with small holes; (3) social exposure to a male (SE m/m): same as group 2 but males were exposed to another male without physical contact; and (4) social cohabitation with mating (SCM): males that mated freely with a receptive female for 6 h. This procedure leads to pair bond formation. Groups 2 and 3 were controls for social interaction. Male prairie voles were injected with 5-bromo-2'-deoxyuridine (BrdU) during the behavioral tests and were sacrificed 48 h later. Brains were processed to identify the new cells (BrdU-positive) and neuron precursor cells (neuroblasts). Our principal findings are that in the dorsal region of the SVZ, SCM and SE m/f and m/m increase the percentage of neuron precursor cells. In the anterior region of the RMS, SE m/f decreases the percentage of neuron precursor cells, and in the medial region SE m/f and m/m decrease the number of new cells and neuron precursor cells. In the infrapyramidal blade of the subgranular zone of the DG, SE m/m and SCM increase the number of new neuron precursor cells and SE m/m increases the percentage of these neurons. Our data suggests that social interaction, as well as sexual stimulation, leads to pair bonding in male voles modulating cell proliferation and differentiation to neuronal precursor cells at the SVZ, RMS, and DG.

The EuroSIDA study: 25 years of scientific achievements.

The EuroSIDA study was initiated in 1994 and follows adult people living with HIV (PLHIV) in 100 collaborating clinics across 35 countries covering all European regions, Israel and Argentina. The study aims to study the long-term virological, immunological and clinical outcomes of PLHIV and to monitor temporal changes and regional differences in outcomes across Europe. Annually collected data include basic demographic characteristics, information on AIDS- and non-AIDS-related clinical events, and details about antiretroviral therapy (ART), hepatitis C treatment and other medications, in addition to a range of laboratory values. The summer 2016 data set held data from a total of 23 071 individuals contributing 174 481 person-years of follow-up, while EuroSIDA's unique plasma repository held over 160 000 samples. Over the past 25 years, close to 300 articles have been published in peer-reviewed journals (h-index 52), covering a range of scientific focus areas, including monitoring of clinical and virological outcomes, ART uptake, efficacy and adverse events, the influence of hepatitis virus coinfection, variation in the quality of HIV care and management across settings and regions, and biomarker research. Recognizing that there remain unresolved issues in the clinical care and management of PLHIV in Europe, EuroSIDA was one of the cohorts to found The International Cohort Consortium of Infectious Disease (RESPOND) cohort consortium on infectious diseases in 2017. In celebration of the EuroSIDA study's 25th anniversary, this article aims to summarize key scientific findings and outline current and future scientific focus areas.

Mating and social exposure induces an opioid-dependent conditioned place preference in male but not in female prairie voles (Microtus ochrogaster).

In rodents, sexual stimulation induces a positive affective state that is evaluated by the conditioned place preference (CPP) test. Opioids are released during sexual behavior and modulate the rewarding properties of this behavior. Prairie voles (Microtus ochrogaster) are a socially monogamous species, in which copulation with cohabitation for 6h induces a pair bond. However, the mating-induced reward state that could contribute to the establishment of the long-term pair bond has not been evaluated in this species. The present study aimed to determine whether one ejaculation or cohabitation with mating for 6h is rewarding for voles. We also evaluated whether this state is opioid dependent. Our results demonstrate that mating with one ejaculation and social cohabitation with mating for 6h induce a CPP in males, while exposure to a sexually receptive female without mating did not induce CPP. In the female vole, mating until one ejaculation, social cohabitation with mating, or exposure to a male without physical interaction for 6h did not induce CPP. To evaluate whether the rewarding state in males is opioid dependent, the antagonist naloxone was injected i.p. The administration of naloxone blocked the rewarding state induced by one ejaculation and by social cohabitation with mating. Our results demonstrate that in the prairie vole, on the basis of the CPP in the testing conditions used here, the stimulation received with one ejaculation and the mating conditions that lead to pair bonding formation may be rewarding for males, and this reward state is opioid dependent.

Human periodontal ligament fibroblasts synthesize C-reactive protein and Th-related cytokines in response to interleukin (IL)-6 trans-signalling.

AIM: To characterize the potential of human periodontal ligament fibroblasts (HPLF) to synthesize CRP and Th-related cytokines in response to IL-6 in periodontal health and apical inflammation. METHODOLOGY: Primary HPLF stimulated with IL-6, soluble(s) IL-6 receptor (R) and controls were assayed for CRP, Th1, Th2, Th17 and Treg-related cytokines by quantitative real-time PCR and ELISA, respectively. IL-6R mRNA expression and its soluble protein levels were screened in HPLF cultures, and ex vivo samples of healthy periodontal ligaments (n = 5) and apical lesions (n = 13). Data were analysed with ANOVA or unpaired t-test. RESULTS: 0.5 ng mL-1 IL-6 plus 1 ng mL-1 of its soluble receptor (sIL-6R) for 24 h was effective in inducing CRP production. IL-6 alone had a mild dose-dependent effect; co-stimulation with sIL-6R significantly enhanced this effect, whereas it was completely abolished by the addition of IL-6R blocking antibody (P < 0.05). Similarly, higher mRNA expression and protein levels of Th1, Th17 and partially Treg-related cytokines were found for IL-6 combined with its soluble receptor versus the nonstimulated group and IL-6R antibody (P < 0.05). IL-6R mRNA expression was slightly induced by IL-6 compared to THP-1 cells, but sILR-6 protein could not be detected in HPLF. High sIL-6R levels were detected in apical lesions and were immunolocalized to mononuclear inflammatory cells and proliferating epithelium. CONCLUSION: IL-6 trans-signalling induced Th1 and Th17-related cytokines and represents an extra-hepatic mechanism for PCR synthesis in human periodontal ligament fibroblasts, contributing to explain the bone-destructive phenotype of apical lesions and eventually its systemic complications.

Natural sesquiterpene lactones induce programmed cell death in Trypanosoma cruzi: a new therapeutic target?

BACKGROUND: Chagas disease or American Trypanosomiasis is caused by the flagellated protozoan parasite Trypanosoma cruzi (T. cruzi) and is recognized by the WHO as one of the world's 17 neglected tropical diseases. Only two drugs (Benznidazol, Bz and Nifurtimox, Nx) are currently accepted for treatment, however they cause severe adverse effects and their efficacy is still controversial. It is then important to explore for new drugs. PURPOSE: Programmed cell death (PCD) in parasites offers interesting new therapeutic targets. The aim of this work was to evaluate the induction of PCD in T. cruzi by two natural sesquiterpene lactones (STLs), dehydroleucodine (DhL) and helenalin (Hln) as compared with the two conventional drugs, Bz and Nx. MATERIAL AND METHODS: Hln and DhL were isolated from aerial parts of Gaillardia megapotamica and Artemisia douglassiana Besser, respectively. Purity of compounds (greater than 95%) was confirmed by (13)C-nuclear magnetic resonance, melting point analysis, and optical rotation. Induction of PCD in T. cruzi epimastigotes and trypomastigotes by DhL, Hln, Bz and Nx was assayed by phosphatidylserine exposure at the parasite surface and by detection of DNA fragmentation using the TUNEL assay. Trypanocidal activity of natural and synthetic compounds was assayed by measuring parasite viability using the MTT method. RESULTS: The two natural STLs, DhL and Hln, induce programmed cell death in both, the replicative epimastigote form and the infective trypomastigote form of T. cruzi. Interestingly, the two conventional antichagasic drugs (Bz and Nx) do not induce programmed cell death. A combination of DhL and either Bz or Nx showed an increased effect of natural compounds and synthetic drugs on the decrease of parasite viability. CONCLUSION: DhL and Hln induce programmed cell death in T. cruzi replicative epimastigote and infective trypomastigote forms, which is a different mechanism of action than the conventional drugs to kill the parasite. Therefore DhL and Hln may offer an interesting option for the treatment of Chagas disease, alone or in combination with conventional drugs.

Deficits in odor-guided behaviors in the transgenic 3xTg-AD female mouse model of Alzheimer׳s disease.

Alzheimer׳s disease (AD) is characterized by a number of alterations including those in cognition and olfaction. An early symptom of AD is decreased olfactory ability, which may affect odor-guided behaviors. To test this possibility we evaluated alterations in sexual incentive motivation, sexual olfactory preference, sexual olfactory discrimination, nursing-relevant olfactory preference and olfactory discrimination in female mice. We tested 3xTg-AD (a triple transgenic model, which is a "knock in" of PS1M146V, APPSwe, and tauP300L) and wild type (WT) female mice when receptive (estrous) and non-receptive (anestrous). Subjects were divided into three groups of different ages: (1) 4-5 months, (2) 10-11 months, and (3) 16-18 months. In the sexual incentive motivation task, the receptive 3xTg-AD females showed no preference for a sexually active male at any age studied, in contrast to the WT females. In the sexual olfactory preference test, the receptive WT females were able to identify sexually active male secretions at all ages, but the oldest (16-18 months old) 3xTg-AD females could not. In addition, the oldest 3xTg-AD females showed no preference for nursing-relevant odors in dam secretions and were unable to discriminate between cinnamon and strawberry odors, indicating olfactory alterations. Thus, the present study suggests that the olfactory deficits in this mouse model are associated with changes in sexual incentive motivation and discrimination of food-related odors.

Repeated paced mating promotes the arrival of more newborn neurons in the main and accessory olfactory bulbs of adult female rats.

We have previously shown that the first-paced mating encounter increases the number of newborn cells in the granule cell layer (Gra; also known as internal cell layer, ICL) of the accessory olfactory bulb (AOB) in the adult female rat (Corona et al., 2011). In the present study we evaluated if repetition of the stimulus (paced mating) could increase the arrival of more newborn neurons in the olfactory bulb generated during the first session of paced sexual contact. Sexually naive female rats were bilaterally ovariectomized, hormonally supplemented with estradiol (E2) and progesterone (P) and randomly assigned to one of four groups: (1) without sexual contact, (2) one session of paced mating, (3) four sessions of paced mating, and (4) four sessions of non-paced mating. We also included a group of gonadally intact females. On the first day of the experiment, all females were i.p. injected with the marker of DNA synthesis bromodeoxyuridine and were killed 16 days later. Blood was collected at sacrifice to determine the plasma levels of E2 and P. The number of newborn neurons that arrived at the ICL of the AOB and the Gra of the main olfactory bulb (MOB) increased, relative to all other groups, only in the group that repeatedly mated under pacing conditions. No differences were found in E2 and P levels between supplemented groups indicating that our results are not influenced by changes in hormone concentrations. We suggest that repeated paced mating promotes the arrival of more newborn neurons in the AOB and MOB.

Calcineurin interacts with PERK and dephosphorylates calnexin to relieve ER stress in mammals and frogs.

BACKGROUND: The accumulation of misfolded proteins within the endoplasmic reticulum (ER) triggers a cellular process known as the Unfolded Protein Response (UPR). One of the earliest responses is the attenuation of protein translation. Little is known about the role that Ca2+ mobilization plays in the early UPR. Work from our group has shown that cytosolic phosphorylation of calnexin (CLNX) controls Ca2+ uptake into the ER via the sarco-endoplasmic reticulum Ca2+-ATPase (SERCA) 2b. METHODOLOGY/PRINCIPAL FINDINGS: Here, we demonstrate that calcineurin (CN), a Ca2+ dependent phosphatase, associates with the (PKR)-like ER kinase (PERK), and promotes PERK auto-phosphorylation. This association, in turn, increases the phosphorylation level of eukaryotic initiation factor-2 alpha (eIF2-alpha) and attenuates protein translation. Data supporting these conclusions were obtained from co-immunoprecipitations, pull-down assays, in-vitro kinase assays, siRNA treatments and [35S]-methionine incorporation measurements. The interaction of CN with PERK was facilitated at elevated cytosolic Ca2+ concentrations and involved the cytosolic domain of PERK. CN levels were rapidly increased by ER stressors, which could be blocked by siRNA treatments for CN-Aalpha in cultured astrocytes. Downregulation of CN blocked subsequent ER-stress-induced increases in phosphorylated elF2-alpha. CN knockdown in Xenopus oocytes predisposed them to induction of apoptosis. We also found that CLNX was dephosphorylated by CN when Ca2+ increased. These data were obtained from [gamma32P]-CLNX immunoprecipitations and Ca2+ imaging measurements. CLNX was dephosphorylated when Xenopus oocytes were treated with ER stressors. Dephosphorylation was pharmacologically blocked by treatment with CN inhibitors. Finally, evidence is presented that PERK phosphorylates CN-A at low resting levels of Ca2+. We further show that phosphorylated CN-A exhibits decreased phosphatase activity, consistent with this regulatory mechanism being shut down as ER homeostasis is re-established. CONCLUSIONS/SIGNIFICANCE: Our data suggest two new complementary roles for CN in the regulation of the early UPR. First, CN binding to PERK enhances inhibition of protein translation to allow the cell time to recover. The induction of the early UPR, as indicated by increased P-elF2alpha, is critically dependent on a translational increase in CN-Aalpha. Second, CN dephosphorylates CLNX and likely removes inhibition of SERCA2b activity, which would aid the rapid restoration of ER Ca2+ homeostasis.

Three-dimensional simulations of a vertically vibrated granular bed including interstitial air.

We present a numerical study of the effect of interstitial air on a vertically vibrated granular bed within one period of oscillation. We use a three-dimensional molecular-dynamics simulation including air phenomenologically. The simulations are validated with experiments made with spherical glass beads in a rectangular container. After validation, results are reported for a granular column of 9000 grains and approximately 50 layers deep (at rest), agitated with a sinusoidal excitation with maximal acceleration 4.7g at 11.7 Hz. We report the evolution of density, granular temperature, and coordination number within a vibration cycle, and the effect of interstitial air on those parameters. In three-dimensional computer simulations we found that the presence of interstitial air can promote the collective motion of the granular material as a whole.

Hallazgos endoscópicos en pacientes con síntomas cardinales de enfermedad de reflujo gastroesofágico

La enfermedad de reflujo gastroesofágico (ERGE) es una enfermedad recurrente relacionada con el flujo retrógrado del contenido gástrico al esófago, con o sin daño tisular a dicho nivel. La Hernia Hiatal (HH) se asocia con ERGE, y se ha relacionado con grados severos de la enfermedad (Esofagitis Erosiva Severa y Esófago de Barrett). Objetivo: Describir la presencia y las alteraciones a nivel de la mucosa esofágica reportadas endoscópicamente en los pacientes que consultan con síntomas de ERGE al servicio de Gastroenterología del Hospital Vargas. Pacientes y métodos: estudio descriptivo de corte transversal, en el cual se evaluaron hallazgos endoscópicos de pacientes que acudieron con síntomas de ERGE a las consultas del servicio de gastroenteologia del Hospital Vargas entre enero-mayo de 2007. Resultados: de 674 pacientes encuestados, 204 pacientes (59 hombres y 145 mujeres)presentaron síntomas de ERGE, a 60 de ellos se les realizó videogastroscopia de manera aleatoria, reportando 23,33% (14 pacientes) con ERGE erosiva, 1,66% (1paciente) con tu submucoso de esófago, 6,66% con esófago Barret y 75% (45 pacientes) sin alteraciones esofágicas. 23 (38,33%) con hernia hiatal, 8 de ellos con esofagitis erosiva. Conclusiones: Nuestro trabajo confirma el valor de la endoscopia digestiva superior en la evaluación de pacientes con síntomas cardinales de ERGE.

Gastro-esophageal reflux disease (GERD) is a recurrent disease related with retrograde progression of gastric contents to the esophagus with or without mucosal damage at this level. Hiatal hernia is associated with GERD and it has been related with severe grades of the disease (severe erosive esophagitis and BarrettÊs esophagus). Aims: to describe the presence of endoscopic features in GERD patientss with cardinals symptoms attended at the Gastroenterology Division of the Vargas Hospital in Caracas. Patients and Methods: this was a descriptive, transversal cohort study in which endoscopic findings in patients with GERD symptoms were evaluated, at the Gastroenterology Service, between January and May 2007. Results: of 674 patients interviewed, 204 patients (59 men and 145 women) presented GERD symptoms; to 60 of them an upper endoscopy randomly was performed. 23,33% (14 patients) had erosive GERD, 1,66% (1 patient) a submucous esophageal tumor, 6,66 % with BarrettÊs esophagus and 75% (45 patients) without esophageal changes, 23 (38,33%) with hiatal hernia, 8 of them with erosive esophagitis. Conclusion: our study supports the importance of performing an upper endoscopy in patients with cardinals symptoms of GERD.

Experiencia en la colocación de prótesis endoscópica en patología biliopancreática

Desde hace dos décadas esta descrita la utilidad de las prótesis endoscópicas, en patología biliopancreática. Objetivo: Mostrar la experiencia del Servicio de Gastroenterología del Hospital Vargas de Caracas en la colocación de prótesis endoscópicas en la patología biliopancreática, describiendo características demográficas, patologías más frecuentes, tasa de éxito en su colocación y complicaciones. Pacientes y Métodos: Estudio descriptivo, retrospectivo. Se revisaron datos de los informes de CPRE de pacientes hospitalizados y ambulatorios evaluados en la institución desde enero 1998 hasta abril 2007. Resultados: Se incluyeron 248 procedimientos de 110 mujeres y 73 hombres, 242 correspondieron a colocación de prótesis biliares (234 de teflón o plástico y 8 autoexpansibles metálicas) y 6 prótesis pancreáticas. Las indicaciones mas frecuentes para la colocación de prótesis fueron: patologías neoplásicas (47%), lesiones de la vía biliar post-quirúrgicas o traumáticas (22%) y litiasis biliar (17%). El éxito de la colocación de la prótesis fue del 99,1%. Se reportaron complicaciones en 4% de los procedimientos, con mayor frecuencia la colangitis (2%) y una mortalidad del 0%. Conclusión: La colocación de prótesis endoscópicas en patologías biliopancreáticas es un procedimiento seguro, con un bajo porcentaje de complicaciones y mortalidad.

The utility of the endoscopic stent have been described for two decades in the biliopancreatic diseases. Aims: To show the Gastroenterology Division of the Hospital Vargas de Caracas experience in placing endoscopic stents in biliopancreatic diseases, describing demographic characteristics more frequent diseases, success rates and complications. Patients and Methods: descriptive and retrospective trial. Features of the reports of PEPR of hospitalized and ambulatory patients seen in the institution from January 1998 to april 2007 were reviewed. Results: 248 procedures from 110 women and 73 men were included, 242 had a biliar stent (234 of Teflon or plastic and 8 metallic selfexpanded) and 6 had pancreatic stents. The more frequent indications for placing the stents were: Tumoral disease, (47%), traumatic or post-surgical lesions of the biliary tract (22%) and biliary stones (17%). The success rate of the placing of stents was 99.1%. The procedureÊs complication rate reported was 4%, being colangitis the most frequent with 2% and a 0% mortality. Conclusion: the placing of endoscopic stents in biliopancreatic diseases is a safe procedure, with a low rate of complications and mortality.

Natural programmed cell death in T. cruzi epimastigotes maintained in axenic cultures.

Trypanosoma cruzi, a parasitic protozoan, is the agent of Chagas' disease or American trypanosomiasis, an endemic pathology in Latin America, affecting up to 18 million people, with high public health costs. Programmed cell death (PCD) has many functions in development and tissue remodeling in metazoans. In protozoa, it could represent concomitant or alternative mechanisms for clonal selection, immune response evasion, and population size regulation. In this work, we describe the natural occurrence of PCD in T. cruzi epimastigotes during the stationary phase of growth in axenic culture or under nutrient deprivation. Thus, we have observed phosphatidylserine externalization, cellular volume decrease, caspase-like protein activity, and DNA fragmentation. Additionally, serum deprivation also induces autophagic characteristics such as monodansylcadaverine-labeled vesicles accumulation and redistribution of proteins homologous to Atg8. In agreement with our results, apoptosis may play an important role in parasite survival. Then, identification and modulation of molecular targets inducing programmed cell death in T. cruzi may lead to new potential therapeutic approaches for Chagas' disease.

Prevalencia de enfermedad por reflujo gastroesofágico en población adulta del área metropolitana de Caracas Venezuela

La enfermedad por reflujo gastroesofágico (ERGE) es uno de los trastornos gastrointestinales con mayor prevalencia; afecta del 10 a 15% de la población general constituyendo una causa frecuente de consulta. Sin embargo, existen pocos reportes acerca de la prevalencia de ERGE en la población general. Objetivos: Determinar la prevalencia de ERGE en la población general adulta del área metropolitana de Caracas y estudiar algunos factores asociados a esta enfermedad. Materiales y métodos: Estudio de corte transversal, realizado en la población general adulta del área metropolitana de Caracas en abril de 2007. Se utilizó una encuesta basada en criterios clínicos epidemiológicos de acuerdo a consensos latinoamericanos y europeos sobre la ERGE. Para el análisis de los resultados se calcularon promedios, medianas y porcentajes. Resultados: De 389 sujetos encuestados, 223 fueron mujeres (57,3%) y 166 hombres (42,7%). El promedio de edad fue 33,89 años. La prevalencia de síntomas cardinales en la ERGE fue 19,02%. En los sujetos con ERGE encontramos que 47,3% ingerían licor al menos un vez al mes, y 21,6% referían hábitos tabáquicos. Conclusión: Se determinó que la prevalencia de la ERGE en la población general adulta del área Metropolitana de Caracas fue de 19,02% encontrándose asociación con el hábito alcohólico.

Gastroesophageal reflux disease (GERD) is one of the gastrointestinals problems with higher prevalence; it affects 10 to 15% of the general population being a frequent cause of medical visit. Nevertheless, there is low number of reports about GERD prevalence. Objectives: to determine GERD prevalence in adult population of the Caracas Metropolitan Area and study some related factors to this disease. Materials and methods: Study of transversal cut, made in adult population in Caracas Metropolitan Area in April 2007. A poll based in clinical and epidemiological criteria in accordance with a Latin- American and European consensus about GERD was used. To analize the results averages, medians and percentages were calculated. Results: of 389 subjects surveyed, 223 were women (57,3%) and 166 were men (42,7%). The mean age of the patients was 33 years old. The cardinals symptoms prevalence was 19,02%. In subjects with GERD we found that 47,3% drank alcohol at least once a week, and 21,6% were smokers. In Conclusion, we found that GERD prevalence in adult population of the Caracas Metropolitan Area was 19, 02% finding a relationship with alcoholic habit.