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Find video protocols related to scientific articles indexed in Pubmed.
Post-traumatic multimodal brain monitoring: response to hypertonic saline.
J. Neurotrauma
PUBLISHED: 09-11-2014
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Abstract Emerging evidence suggests that hypertonic saline (HTS) is efficient in decreasing intracranial pressure (ICP). However there is no consensus about its interaction with brain hemodynamics and oxygenation. In this study, we investigated brain response to HTS bolus with multimodal monitoring after severe traumatic brain injury (TBI). We included 18 consecutive TBI patients during 10 days after neurocritical care unit admission. Continuous brain monitoring applied included ICP, tissue oxygenation (PtO2) and cerebral blood flow (CBF). Cerebral perfusion pressure (CPP), cerebrovascular resistance (CVR), and reactivity indices related to pressure (PRx) and flow (CBFx) were calculated. ICM+software was used to collect and analyze monitoring data. Eleven of 18 (61%) patients developed 99 episodes of intracranial hypertension (IHT) greater than 20?mm Hg that were managed with 20% HTS bolus. Analysis over time was performed with linear mixed-effects regression modelling. After HTS bolus, ICP and CPP improved over time (p<0.001) following a quadratic model. From baseline to 120?min, ICP had a mean decrease of 6.2?mm Hg and CPP a mean increase of 3.1?mmHg. Mean increase in CBF was 7.8?mL/min/100?g (p<0.001) and mean decrease in CVR reached 0.4?mm Hg*min*100?g/mL (p=0.01). Both changes preceded pressures improvement. PtO2 exhibited a marginal increase and no significant models for time behaviour could be fitted. PRx and CBFx were best described by a linear decreasing model showing autoregulation recover after HTS (p=0.01 and p=0.04 respectively). During evaluation, CO2 remained constant and sodium level did not exhibit significant variation. In conclusion, management of IHT with 20% HTS significantly improves cerebral hemodynamics and cerebrovascular reactivity with recovery of CBF appearing before rise in CPP and decrease in ICP. In spite of cerebral hemodynamic improvement, no significant changes in brain oxygenation were identified.
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Risk factors for severe influenza A-related pneumonia in adult cohort, Mexico, 2013-14.
Emerging Infect. Dis.
PUBLISHED: 08-23-2014
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During the 2013-14 influenza season, we assessed characteristics of 102 adults with suspected influenza pneumonia in a hospital in Mexico; most were unvaccinated. More comorbidities and severity of illness were found than for patients admitted during the 2009-10 influenza pandemic. Vaccination policies should focus on risk factors.
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Interactions of isoniazid with membrane models: implications for drug mechanism of action.
Chem. Phys. Lipids
PUBLISHED: 03-25-2014
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This work focuses on the application of biophysical techniques to assess the interaction of isoniazid (INH) with three-dimensional cell membrane mimetic models. Liposomes made of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) were used as cell membrane lipids, being the interactions of the drug studied under different pH conditions to mimic the in vivo near neutral physiological pH found in the cytoplasm and the acidic conditions encountered in the protective gastric barrier and in the macrophage intracellular acidic compartments (i.e., phagosomes and phagolysomes). The effect of INH on the biophysical parameters of the cell membrane lipids was assessed by dynamic light scattering (DLS) and small-angle X-ray scattering (SAXS). The overall results highlighted the importance of the pH for the interactions of INH with biological membranes. A relationship between the effect of INH on the biophysical properties of the membranes and the pH was established. In fact, the experimental results point to a higher affinity of the drug to the acidic environments, which not only explain its sequestration in the infected cells but also some of its side-effects.
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Genome sequence of the model sulfate reducer Desulfovibrio gigas: a comparative analysis within the Desulfovibrio genus.
Microbiologyopen
PUBLISHED: 03-20-2014
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Desulfovibrio gigas is a model organism of sulfate-reducing bacteria of which energy metabolism and stress response have been extensively studied. The complete genomic context of this organism was however, not yet available. The sequencing of the D. gigas genome provides insights into the integrated network of energy conserving complexes and structures present in this bacterium. Comparison with genomes of other Desulfovibrio spp. reveals the presence of two different CRISPR/Cas systems in D. gigas. Phylogenetic analysis using conserved protein sequences (encoded by rpoB and gyrB) indicates two main groups of Desulfovibrio spp, being D. gigas more closely related to D. vulgaris and D. desulfuricans strains. Gene duplications were found such as those encoding fumarate reductase, formate dehydrogenase, and superoxide dismutase. Complexes not yet described within Desulfovibrio genus were identified: Mnh complex, a v-type ATP-synthase as well as genes encoding the MinCDE system that could be responsible for the larger size of D. gigas when compared to other members of the genus. A low number of hydrogenases and the absence of the codh/acs and pfl genes, both present in D. vulgaris strains, indicate that intermediate cycling mechanisms may contribute substantially less to the energy gain in D. gigas compared to other Desulfovibrio spp. This might be compensated by the presence of other unique genomic arrangements of complexes such as the Rnf and the Hdr/Flox, or by the presence of NAD(P)H related complexes, like the Nuo, NfnAB or Mnh.
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Systemic but not topical TRAIL-expressing mesenchymal stem cells reduce tumour growth in malignant mesothelioma.
Thorax
PUBLISHED: 02-24-2014
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Malignant pleural mesothelioma is a rare but devastating cancer of the pleural lining with no effective treatment. The tumour is often diffusely spread throughout the chest cavity, making surgical resection difficult, while systemic chemotherapy offers limited benefit. Bone marrow-derived mesenchymal stem cells (MSCs) home to and incorporate into tumour stroma, making them good candidates to deliver anticancer therapies. Tumour necrosis factor-related apoptosis-inducing ligand (TRAIL) is a pro-apoptotic molecule that selectively induces apoptosis in cancer cells, leaving healthy cells unaffected. We hypothesised that human MSCs expressing TRAIL (MSCTRAIL) would home to an in vivo model of malignant pleural mesothelioma and reduce tumour growth. Human MSCs transduced with a lentiviral vector encoding TRAIL were shown in vitro to kill multiple malignant mesothelioma cell lines as predicted by sensitivity to recombinant TRAIL (rTRAIL). In vivo MSC homing was delineated using dual fluorescence and bioluminescent imaging, and we observed that higher levels of MSC engraftment occur after intravenous delivery compared with intrapleural delivery of MSCs. Finally, we show that intravenous delivery of MSCTRAIL results in a reduction in malignant pleural mesothelioma tumour growth in vivo via an increase in tumour cell apoptosis.
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Evaluation of the effect of rifampicin on the biophysical properties of the membranes: significance for therapeutic and side effects.
Int J Pharm
PUBLISHED: 01-18-2014
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This work aims to study the biophysical interactions of rifampicin (RIF) with three-dimensional macrophage membrane models, under environments with physiological and pathological relevance. The interaction of RIF with liposomes formed by 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) in different pH values (i.e., 5.0, 6.2 and 7.4) was investigated by several biophysical techniques. The RIF's membrane concentration was quantified by partition coefficient (Kp) using derivative spectrophotometry. To predict the drug's location across the membrane, fluorescence quenching studies were performed using liposomes labeled with two different fluorescence probes. The effect of the drug on the biophysical parameters of the membrane was carried out by dynamic light scattering (DLS), and small-angle X-ray scattering (SAXS). The overall results confirm that the interactions of RIF with membranes are pH-dependent, being much more pronounced at the acidic pH. A correlation between the effect of RIF on the biophysical properties of the membranes and the pH was found, which may be useful in the development of novel analogs with higher efficacy and fewer side effects, and also to understand the higher selectivity of RIF to the membranes of the infected cells, as well as its side effects.
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A social cost perspective in the wake of the Portuguese strategy for the fight against drugs.
Int. J. Drug Policy
PUBLISHED: 01-02-2014
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The Portuguese National Strategy for the Fight Against Drugs (NSFAD), approved in 1999, was explicitly grounded on the values of humanism and pragmatism and paved the way for the decriminalization of illicit drug use in Portugal in 2000. This paper presents an analysis of the social costs of illicit drug use in the wake of the strategy's approval. Taking into consideration health and non-health related costs, we find that that the social cost of drugs decreased by 12% in the five years following the NSFAD's approval and by a rather significant 18% in the eleven-year period following its approval. Whilst the reduction of legal system costs (possibly associated with the decriminalization of drug consumption) is clearly one of the main explanatory factors, it is not the only one. In particular, the rather significant reduction of health-related costs has also played an important role.
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Plasma nutrient status of patients with Alzheimer's disease: Systematic review and meta-analysis.
Alzheimers Dement
PUBLISHED: 01-01-2014
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Alzheimer disease (AD) patients are at risk of nutritional insufficiencies because of physiological and psychological factors. Nutritional compounds are postulated to play a role in the pathophysiological processes that are affected in AD. We here provide the first systematic review and meta-analysis that compares plasma levels of micronutrients and fatty acids in AD patients to those in cognitively intact elderly controls. A secondary objective was to explore the presence of different plasma nutrient levels between AD and control populations that did not differ in measures of protein/energy nourishment.
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[Merkel cell carcinoma experience in a reference medical center.]
Rev Med Inst Mex Seguro Soc
PUBLISHED: 12-03-2013
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Background: Merkel cell carcinoma is a rare tumor that occurs on areas exposed to ultraviolet light. It is usually asymptomatic and it is diagnosed late often. The treatment is surgical, associated with adjuvant radiotherapy. The objective was to present the experience in the management of Merkel cell carcinoma in a reference medical center. Methods: all patients with Merkel cell carcinoma treated at the Instituto de Investigaciones Médico-Biológicas of the Universidad Veracruzana during the period 2008 to 2011 were studied. Sex, age, evolution time, tumor localization, size, metastases and treatment were analyzed. Results: of 3217 patients treated, three cases were Merkel cell carcinoma (0.09 %), their age was 52.1 ± 14.17, male predominance of 66.67 %; the evolution time was of 29.66 ± 35.36 months; the tumour localization was on inguinal region, anterior chest and left arm; the noodle size was of 6.0 ± 5.19 cm; two patients had lymph node metastases. In two cases, resection and lymphadenectomy were performed. They all received radiation therapy and chemotherapy in one case. Histologically the medium variant predominated; immunohistochemistry was positive in the three cases. One patient died ten months after the study was done. Conclusions: our experience is similar with others authors, Merkel cell carcinoma is a rare tumor, usually diagnosed late, and it has poor survival.
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Autistic-like behavioural and neurochemical changes in a mouse model of food allergy.
Behav. Brain Res.
PUBLISHED: 11-05-2013
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Food allergy has been suggested to contribute to the expression of psychological and psychiatric traits, including disturbed social behaviour and repetitive behaviour inherent in autism spectrum disorders (ASD). Most research in this field receives little attention, since fundamental evidence showing direct effects of food allergic immune responses on social behaviour is very limited. In the present study, we show that a food allergic reaction to cows milk protein, induced shortly after weaning, reduced social behaviour and increased repetitive behaviour in mice. This food allergic reaction increased levels of serotonin (5-hydroxytryptamine; 5-HT) and the number of 5-HT positive cells, and decreased levels of 5-hydroxyindoleacetic acid (5-HIAA) in the intestine. Behavioural changes in food allergic mice were accompanied by reduced dopaminergic activity in the prefrontal cortex. Furthermore, neuronal activation (c-Fos expression) was increased in the prefrontal cortex and reduced in the paraventricular nucleus of the hypothalamus after exposure to a social target. We hypothesize that an intestinal allergic response regulates complex, but critical, neuroimmune interactions, thereby affecting brain circuits involved in social interaction, repetitive behaviour and cognition. Together with a genetic predisposition and multiple environmental factors, these effects of allergic immune activation may exacerbate behavioural abnormalities in patients with ASD.
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Food allergy and food-based therapies in neurodevelopmental disorders.
Pediatr Allergy Immunol
PUBLISHED: 09-15-2013
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Autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD) are neurodevelopmental disorders which occur in childhood and may persist into adulthood. Although the etiology of these disorders is largely unknown, genetic and environmental factors are thought to play a role in the development of ASD and ADHD. Allergic immune reactions, in prenatal and postnatal phases, are examples of these environmental factors, and adverse reactions to foods are reported in these children. In this review, we address the clinical and preclinical findings of (food) allergy in ASD and ADHD and suggest possible underlying mechanisms. Furthermore, opportunities for nutritional interventions in neurodevelopmental disorders are provided.
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Intestinal inflammation in a murine model of autism spectrum disorders.
Brain Behav. Immun.
PUBLISHED: 09-13-2013
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Autism spectrum disorder (ASD) is a cluster of neurodevelopmental disorders characterized by impairments in communication, social interest and stereotypical behaviour. Dysfunction of the intestinal tract is reported in patients with ASD and implicated in the development and severity of ASD symptoms. However, more research is required to investigate the association of intestinal problems with ASD and the potential underlying mechanisms. The purpose of this study was to investigate comorbid symptoms of intestinal inflammation in a murine model of ASD induced by prenatal exposure to valproic acid (VPA). Pregnant BALB/c females were treated subcutaneously with 600mg/kg VPA or phosphate buffered saline on gestational day 11. Offspring were housed with their mother until weaning on postnatal day 21 (P21). All pups were exposed to a social behaviour test on P28. Inflammatory correlates and activity of the serotonergic system were measured in brain and intestinal tissue. Here we demonstrate, in addition to reduced social behaviour and increased expression of neuroinflammatory markers in the brain, that VPA in utero- exposed male offspring showed epithelial cell loss and neutrophil infiltration in the intestinal tract. Furthermore, reduced levels of serotonin were not only observed the prefrontal cortex and amygdala of VPA in utero- exposed males, but also in the small intestine. Overall, we demonstrate that gender-specific inflammatory conditions are present in the small intestines of VPA in utero- exposed mice and are accompanied by a disturbed serotonergic system in the brain as well as in the intestinal tract.
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Function of formate dehydrogenases in Desulfovibrio vulgaris Hildenborough energy metabolism.
Microbiology (Reading, Engl.)
PUBLISHED: 05-31-2013
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The genome of the sulfate-reducing bacterium Desulfovibrio vulgaris Hildenborough encodes three formate dehydrogenases (FDHs), two of which are soluble periplasmic enzymes (FdhAB and FdhABC3) and one that is periplasmic but membrane-associated (FdhM). FdhAB and FdhABC3 were recently shown to be the main enzymes present during growth with lactate, formate or hydrogen. To address the role of these two enzymes, ?fdhAB and ?fdhABC3, mutants were generated and studied. Different phenotypes were observed in the presence of either molybdenum or tungsten, since both enzymes were important for growth on formate in the presence of Mo, whereas in the presence of W only FdhAB played a role. Both ?fdhAB and ?fdhABC3 mutants displayed defects in growth with lactate and sulfate providing the first direct evidence for the involvement of formate cycling under these conditions. In support of this mechanism, incubation of concentrated cell suspensions of the mutant strains with lactate and limiting sulfate also gave elevated formate concentrations, as compared to the wild-type strain. In contrast, both mutants grew similarly to the wild-type with H2 and sulfate. In the absence of sulfate, the wild-type D. vulgaris cells produced formate when supplied with H2 and CO2, which resulted from CO2 reduction by the periplasmic FDHs. The conversion of H2 and CO2 to formate allows the reversible storage of reducing power in a much more soluble molecule. Furthermore, we propose this may be an expression of the ability of some sulfate-reducing bacteria to grow by hydrogen oxidation, in syntrophy with organisms that consume formate, but are less efficient in H2 utilization.
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Endohelminth parasites of the blacktail comber Serranus atricauda (Pisces: Serranidae), from Madeira Archipelago (Atlantic Ocean).
Dis. Aquat. Org.
PUBLISHED: 03-14-2013
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Four different endohelminth parasite taxa were found in the viscera of the blacktail comber Serranus atricauda Günther, 1874 caught in the Madeira Archipelago. Nematodes were the dominant group, represented by 2 different taxa, Hysterothylacium spp. Ward & Magath, 1917 and Procamallanus (Spirocamallanus) halitrophus Fusco & Overstreet, 1978 comb. n. Plerocerci of the trypanorhynch Pseudogrillotia epinepheli (synonym: Grillotia epinepheli) Scholz, Garippa & Scala, 1993, and cystacanths of the acanthocephalan Bolbosoma vasculosum Rudolphi, 1819 were found in the visceral cavity. New host records for P. (S.) halitrophus and P. epinepheli and the extension of the geographic distribution of these 2 parasite species provide evidence of parasite transference between the Madeira Archipelago, the Mediterranean and the Gulf of Mexico. The paucity of the parasite fauna of blacktail comber reflect a combination of fish host selective feeding on particular dietary items and its territorial behaviour.
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Novel methodology based on biomimetic superhydrophobic substrates to immobilize cells and proteins in hydrogel spheres for applications in bone regeneration.
Tissue Eng Part A
PUBLISHED: 02-19-2013
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Cell-based therapies for regenerative medicine have been characterized by the low retention and integration of injected cells into host structures. Cell immobilization in hydrogels for target cell delivery has been developed to circumvent this issue. In this work mesenchymal stem cells isolated from Wistar rats bone marrow (rMSCs) were immobilized in alginate beads fabricated using an innovative approach involving the gellification of the liquid precursor droplets onto biomimetic superhydrophobic surfaces without the need of any precipitation bath. The process occurred in mild conditions preventing the loss of cell viability. Furthermore, fibronectin (FN) was also immobilized inside alginate beads with high efficiency in order to mimic the composition of the extracellular matrix. This process occurred in a very fast way (around 5?min), at room temperature, without aggressive mechanical strengths or particle aggregation. The methodology employed allowed the production of alginate beads exhibiting a homogenous rMSCs and FN distribution. Encapsulated rMSCs remained viable and were released from the alginate for more than 20 days. In vivo assays were also performed, by implanting these particles in a calvarial bone defect to evaluate their potential for bone tissue regeneration. Microcomputed tomography and histological analysis results showed that this hybrid system accelerated bone regeneration process. The methodology employed had a dual role by preventing cell and FN loss and avoiding any contamination of the beads or exchange of molecules with the surrounding environment. In principle, the method used for cell encapsulation could be extended to other systems aimed to be used in tissue regeneration strategies.
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The stability of self-reported adverse experiences in childhood: a longitudinal study on obesity.
J Interpers Violence
PUBLISHED: 01-29-2013
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The literature on the effect of maltreatment has revealed several methodological problems of retrospective studies, such as the validity and stability of retrospective reports, which may be influenced by factors such as ones mental health at the time of the report. This study aims to assess the temporal stability of self-reported adverse childhood experiences at three different time points, separated by 6 months each, and to analyze the relationship between general psychopathology and the number of reported experiences. Thirty obese participants responded to the Portuguese version of the Childhood History Questionnaire, a self-report measure that assesses adverse childhood experiences, and the Brief Symptom Inventory. The results suggest that adverse childhood experiences are common in these participants (time 1: X = 1.87, SD = 1.3; time 2: X = 1.98, SD = 1.6; time 3: X = 1.98, SD = 1.6). The agreement levels, as measured by kappa values, were satisfactory for the dimensions of maltreatment focused on the individual, with kappas ranging between .34 and .44. Our participants did not exhibit psychopathology at any of the time points, and the psychopathological symptoms were not related to total adversity reported. The major contribution of this study is the comparison of self-reports at three time points, separated by significant time intervals, and the inclusion of 10 different dimensions of childhood adversity. The data show an adequate stability in the report of maltreatment toward the individual (abuse and physical neglect) and in specific aspects of adversity in the family.
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An analysis and validation pipeline for large-scale RNAi-based screens.
Sci Rep
PUBLISHED: 01-16-2013
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Large-scale RNAi-based screens are a major technology, but require adequate prioritization and validation of candidate genes from the primary screen. In this work, we performed a large-scale pooled shRNA screen in mouse embryonic stem cells (ESCs) to discover genes associated with oxidative stress resistance and found several candidates. We then developed a bioinformatics pipeline to prioritize these candidates incorporating effect sizes, functional enrichment analysis, interaction networks and gene expression information. To validate candidates, we mixed normal cells with cells expressing the shRNA coupled to a fluorescent protein, which allows control cells to be used as an internal standard, and thus we could detect shRNAs with subtle effects. Although we did not identify genes associated with oxidative stress resistance, as a proof-of-concept of our pipeline we demonstrate a detrimental role of Edd1 silencing in ESC growth. Our methods may be useful for candidate gene prioritization of large-scale RNAi-based screens.
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HLA-DRB1 Class II antigen level alleles are associated with persistent HPV infection in Mexican women; a pilot study.
Infect. Agents Cancer
PUBLISHED: 01-09-2013
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Persistent infection with high-risk human papillomavirus (HPV) is a major risk factor for malignant lesions and cervical cancer. A widely studied element in the search for genetic factors influencing risk HPV infection diseases is allelic variation of the human leukocyte antigen (HLA) locus. The study was designed to search for HLA susceptibility alleles contributing to the persistence of HPV infection in Mexican women.
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Gathering insights on disease etiology from gene expression profiles of healthy tissues.
Bioinformatics
PUBLISHED: 10-11-2011
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Gene expression profiles have been widely used to study disease states. It may be possible, however, to gather insights into human diseases by comparing gene expression profiles of healthy organs with different disease incidence or severity. We tested this hypothesis and developed an approach to identify candidate genes associated with disease development by focusing on cancer incidence since it varies greatly across human organs.
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Pathways underlying the gut-to-brain connection in autism spectrum disorders as future targets for disease management.
Eur. J. Pharmacol.
PUBLISHED: 06-17-2011
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Autism spectrum disorders (ASDs) are pervasive neurodevelopmental disorders, characterized by impairments in social interaction and communication and the presence of limited, repetitive and stereotyped interests and behavior. Bowel symptoms are frequently reported in children with ASD and a potential role for gastrointestinal disturbances in ASD has been suggested. This review focuses on the importance of (allergic) gastrointestinal problems in ASD. We provide an overview of the possible gut-to-brain pathways and discuss opportunities for pharmaceutical and/or nutritional approaches for therapy.
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Prognostic value of a new cardiopulmonary exercise testing parameter in chronic heart failure: oxygen uptake efficiency at peak exercise - comparison with oxygen uptake efficiency slope.
Rev Port Cardiol
PUBLISHED: 05-11-2011
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A growing body of evidence shows the prognostic value of oxygen uptake efficiency slope (OUES), a cardiopulmonary exercise test (CPET) parameter derived from the logarithmic relationship between O(2) consumption (VO(2)) and minute ventilation (VE) in patients with chronic heart failure (CHF).
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[Thoracic fluid content - a possible determinant of ventilatory efficiency in patients with heart failure].
Rev Port Cardiol
PUBLISHED: 05-11-2011
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Ventilatory efficiency, evaluated by cardiopulmonary exercise testing (CPET), has considerable prognostic value in patients with chronic heart failure (CHF) due to left ventricular systolic dysfunction (LVSD). Its determinants nevertheless remain controversial.
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Tungsten and molybdenum regulation of formate dehydrogenase expression in Desulfovibrio vulgaris Hildenborough.
J. Bacteriol.
PUBLISHED: 04-15-2011
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Formate is an important energy substrate for sulfate-reducing bacteria in natural environments, and both molybdenum- and tungsten-containing formate dehydrogenases have been reported in these organisms. In this work, we studied the effect of both metals on the levels of the three formate dehydrogenases encoded in the genome of Desulfovibrio vulgaris Hildenborough, with lactate, formate, or hydrogen as electron donors. Using Western blot analysis, quantitative real-time PCR, activity-stained gels, and protein purification, we show that a metal-dependent regulatory mechanism is present, resulting in the dimeric FdhAB protein being the main enzyme present in cells grown in the presence of tungsten and the trimeric FdhABC? protein being the main enzyme in cells grown in the presence of molybdenum. The putatively membrane-associated formate dehydrogenase is detected only at low levels after growth with tungsten. Purification of the three enzymes and metal analysis shows that FdhABC? specifically incorporates Mo, whereas FdhAB can incorporate both metals. The FdhAB enzyme has a much higher catalytic efficiency than the other two. Since sulfate reducers are likely to experience high sulfide concentrations that may result in low Mo bioavailability, the ability to use W is likely to constitute a selective advantage.
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A comparative genomic analysis of energy metabolism in sulfate reducing bacteria and archaea.
Front Microbiol
PUBLISHED: 02-03-2011
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The number of sequenced genomes of sulfate reducing organisms (SRO) has increased significantly in the recent years, providing an opportunity for a broader perspective into their energy metabolism. In this work we carried out a comparative survey of energy metabolism genes found in 25 available genomes of SRO. This analysis revealed a higher diversity of possible energy conserving pathways than classically considered to be present in these organisms, and permitted the identification of new proteins not known to be present in this group. The Deltaproteobacteria (and Thermodesulfovibrio yellowstonii) are characterized by a large number of cytochromes c and cytochrome c-associated membrane redox complexes, indicating that periplasmic electron transfer pathways are important in these bacteria. The Archaea and Clostridia groups contain practically no cytochromes c or associated membrane complexes. However, despite the absence of a periplasmic space, a few extracytoplasmic membrane redox proteins were detected in the Gram-positive bacteria. Several ion-translocating complexes were detected in SRO including H(+)-pyrophosphatases, complex I homologs, Rnf, and Ech/Coo hydrogenases. Furthermore, we found evidence that cytoplasmic electron bifurcating mechanisms, recently described for other anaerobes, are also likely to play an important role in energy metabolism of SRO. A number of cytoplasmic [NiFe] and [FeFe] hydrogenases, formate dehydrogenases, and heterodisulfide reductase-related proteins are likely candidates to be involved in energy coupling through electron bifurcation, from diverse electron donors such as H(2), formate, pyruvate, NAD(P)H, ?-oxidation, and others. In conclusion, this analysis indicates that energy metabolism of SRO is far more versatile than previously considered, and that both chemiosmotic and flavin-based electron bifurcating mechanisms provide alternative strategies for energy conservation.
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Combining ventilatory efficiency and peak oxygen consumption in the prognostic assessment of patients with chronic heart failure.
Rev Port Cardiol
PUBLISHED: 12-25-2010
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Cardiopulmonary exercise testing (CPET) is an objective method for assessment of functional capacity and for prognostic stratification of patients with chronic heart failure (CHF). In this study, we analyzed the prognostic value of a recently described CPET-derived parameter, the minute ventilation to carbon dioxide production slope normalized for peak oxygen consumption (VE/VCO2 slope/pVO2).
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Initial experience with the Presillion stent in an unselected population: immediate and six-month outcomes.
Rev Port Cardiol
PUBLISHED: 08-26-2010
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The release of a new bare metal stent (BMS), the Presillion stent, whose main innovative feature is its reduced strut thickness, has created expectations that it may reduce neointimal proliferation and consequently lower the restenosis rate.
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The genetic architecture of maize flowering time.
Science
PUBLISHED: 08-08-2009
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Flowering time is a complex trait that controls adaptation of plants to their local environment in the outcrossing species Zea mays (maize). We dissected variation for flowering time with a set of 5000 recombinant inbred lines (maize Nested Association Mapping population, NAM). Nearly a million plants were assayed in eight environments but showed no evidence for any single large-effect quantitative trait loci (QTLs). Instead, we identified evidence for numerous small-effect QTLs shared among families; however, allelic effects differ across founder lines. We identified no individual QTLs at which allelic effects are determined by geographic origin or large effects for epistasis or environmental interactions. Thus, a simple additive model accurately predicts flowering time for maize, in contrast to the genetic architecture observed in the selfing plant species rice and Arabidopsis.
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Alterations in autonomic response head-up tilt testing in paroxysmal atrial fibrillation patients: a wavelet analysis.
Rev Port Cardiol
PUBLISHED: 06-02-2009
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The autonomic nervous system (ANS) is known to be an important modulator in the pathogenesis of paroxysmal atrial fibrillation (PAF). Changes in ANS control of heart rate variability (HRV) occur during orthostatism to maintain cardiovascular homeostasis. Wavelet transform has emerged as a useful tool that provides time-frequency decomposition of the signal under investigation, enabling intermittent components of transient phenomena to be analyzed.
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A genomic island of the sulfate-reducing bacterium Desulfovibrio vulgaris Hildenborough promotes survival under stress conditions while decreasing the efficiency of anaerobic growth.
Environ. Microbiol.
PUBLISHED: 05-23-2009
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A 47 kb genomic island (GEI) bracketed by 50 bp direct repeats, containing 52 annotated genes, was found to delete spontaneously from the genome of Desulfovibrio vulgaris Hildenborough. The island contains genes for site-specific recombinases and transposases, rubredoxin:oxygen oxidoreductase-1 (Roo1) and hybrid cluster protein-1 (Hcp1), which promote survival in air and nitrite stress. The numbering distinguishes these from the Roo2 and Hcp2 homologues for which the genes are located elsewhere in the genome. Cells with and without the island (GEI(+) and GEI(-) cells respectively) were obtained by colony purification. GEI(-) cells arise in anaerobic cultures of colony-purified GEI(+) cells, indicating that the site-specific recombinases encoded by the island actively delete this region. GEI(+) cells survive better in microaerophilic conditions due to the presence of Roo1, whereas the Hcps appear to prevent inhibition by sulfur and polysulfide, which are formed by chemical reaction of sulfide and nitrite. Hence, the island confers resistance to oxygen and nitrite stress. However, GEI(-) cells have a higher growth rate in anaerobic media. Microarrays and enzyme activity stains indicated that the GEI(-) cells have increased expression of genes, which promote anaerobic energy conservation, explaining the higher growth rate. Hence, while lowering the efficiency of anaerobic metabolism, the GEI increases the fitness of D. vulgaris under stress conditions, a feature reminiscent of pathogenicity islands which allow more effective colonization of environments provided by the targeted hosts.
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Obesity and treatment meanings in bariatric surgery candidates: a qualitative study.
Obes Surg
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This study used a qualitative approach to comprehend how the morbid obese conceptualize and deal with obesity and obesity treatment, with the particular aim of exploring the expectations and beliefs about the exigencies and the impact of bariatric surgery.
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Balancing motherhood and drug addiction: the transition to parenthood of addicted mothers.
J Health Psychol
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This is a study about balancing motherhood and drug addiction, during the transition to parenthood. Few studies have dealt with the parental experience of drug-addicted mothers. The participants included 24 drug-addicted mothers, on methadone, with ages 25-42 and with children 1-32 months of age. Semi-structured interviews were conducted and analyzed according to Grounded Theory. The mothers main concern was the ambivalence they felt towards pregnancy/motherhood and drug addiction, which was associated with strong feelings of guilt. Confronted with this ambivalence their maternal role becomes merely functional. They focus on providing the basic care to the child, but show little willingness to talk or play. Social support, especially from the partner seems to have a positive role.
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Electron transfer between periplasmic formate dehydrogenase and cytochromes c in Desulfovibrio desulfuricans ATCC 27774.
J. Biol. Inorg. Chem.
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Desulfovibrio spp. are sulfate-reducing organisms characterized by having multiple periplasmic hydrogenases and formate dehydrogenases (FDHs). In contrast to enzymes in most bacteria, these enzymes do not reduce directly the quinone pool, but transfer electrons to soluble cytochromes c. Several studies have investigated electron transfer with hydrogenases, but comparatively less is known about FDHs. In this work we conducted experiments to assess potential electron transfer pathways resulting from formate oxidation in Desulfovibrio desulfuricans ATCC 27774. This organism can grow on sulfate and on nitrate, and contains a single soluble periplasmic FDH that includes a cytochrome c (3) like subunit (FdhABC(3)). It has also a unique cytochrome c composition, including two cytochromes c not yet isolated from other species, the split-Soret and nine-heme cytochromes, besides a tetraheme type I cytochrome c (3) (TpIc (3)). The FDH activity and cytochrome composition of cells grown with lactate or formate and nitrate or sulfate were determined, and the electron transfer between FDH and these cytochromes was investigated. We studied also the reduction of the Dsr complex and of the monoheme cytochrome c-553, previously proposed to be the physiological partner of FDH. FdhABC(3) was able to reduce the c-553, TpIc (3), and split-Soret cytochromes with a high rate. For comparison, the same experiments were performed with the [NiFe] hydrogenase from the same organism. This study shows that FdhABC(3) can directly reduce the periplasmic cytochrome c network, feeding electrons into several alternative metabolic pathways, which explains the advantage of not having an associated membrane subunit.
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Portable miniaturized extracorporeal membrane oxygenation systems for H1N1-related severe acute respiratory distress syndrome: a case series.
J Crit Care
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Technological advances improved the practice of "modern" extracorporeal membrane oxygenation (ECMO). In the present report, we describe the experience of a referral ECMO center using portable miniaturized ECMO systems for H1N1-related severe acute respiratory distress syndrome (ARDS).
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JoVE Visualize is a tool created to match the last 5 years of PubMed publications to methods in JoVE's video library.

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In developing our video relationships, we compare around 5 million PubMed articles to our library of over 4,500 methods videos. In some cases the language used in the PubMed abstracts makes matching that content to a JoVE video difficult. In other cases, there happens not to be any content in our video library that is relevant to the topic of a given abstract. In these cases, our algorithms are trying their best to display videos with relevant content, which can sometimes result in matched videos with only a slight relation.