Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 109
Filtrar
Mais filtros

Tipo de documento
Intervalo de ano de publicação
1.
Sci Sports ; 37(7): 639-642, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36062207

RESUMO

The potential role of physical activity and a healthy diet in increasing nitric oxide during COVID-19 outbreak. This manuscript presents a perspective which provide new insights about the promising role of nitric oxide on COVID-19. Demonstration that nitric oxide was an important cornerstone against viral infections, including SARS-CoV-1 in 2009. Thus, given the concern that higher NO- could improve endothelial health and might be a protection factor against COVID-19, should we critically consider non-pharmacological strategies that increase NO- bioavailability as medicine for COVID-19? From this perspective, we highlight the potential effect of physical activity and healthy diet in stimulating the increase of NO- bioavailability.


Les rôles potentiels de l'activité physique et d'une alimentation saine dans l'augmentation de l'oxyde nitrique pendant l'épidémie de COVID-19. Ce manuscrit présente une perspective qui fournit de nouvelles informations sur le rôle prometteur de l'oxyde nitrique sur la protection contre le risque de COVID-19. Dès 2009, a été évoqué le rôle de l'oxyde nitrique contre le risque d'infections virales, y compris contre la première pandémie liée au coronavirus SARS-CoV-1. Compte tenu de l'hypothèse qu'une augmentation de la production de NO− permettrait d'améliorer la santé endothéliale et pourrait être un facteur de protection contre COVID-19, la question se pose sur la promotion de stratégies non pharmacologiques qui augmentent la biodisponibilité du NO−. C'est dans cette perspective que sont, ici, discutés les effets potentiels de l'activité physique et d'une alimentation saine pour stimuler l'augmentation de la biodisponibilité du NO et la prévention contre la COVID-19.

2.
Appl Opt ; 59(14): 4303-4313, 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32400406

RESUMO

This paper presents a new, to the best of our knowledge, methodology for the thermal compensation of background heating in thermograms of composites. The technique analyzes the spatial data of the thermal images obtained from a pulsed thermography inspection and automatically calculates the optimal parameters of a predefined objective function. These parameters are obtained by curve fitting using the least squares method and model the temperature distribution of the image background using the proposed objective function. To verify the methodology, we use real and synthetic images of a sample of carbon-fiber-reinforced plastic (CFRP) with defects, with diameter/depth ratios that range between 15.0 and 75.0 and between 1.7 and 90.0, respectively. The performance of the method is tested using a local and a global definition of the signal-to-noise ratio (SNR) and is statistically validated by analysis of variance. The average performance values obtained were 55.0dB and 7.0dB on synthetic images and real images, respectively. The proposed method provides superior and statistically significant differences compared to techniques reported in the literature for contrast enhancement [e.g., differential absolute contrast (DAC) and background thermal compensation by filtering (BTCF)]. Unlike contrast normalization (CN), the proposed technique stands out since it does not need to predefine variables, select reference regions, have prior knowledge of the partial (or complete) state of the material, or analyze totally (or partially) the temporal evolution of the temperature or any characteristic derived from it.

3.
Appl Opt ; 58(13): 3620-3629, 2019 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-31044864

RESUMO

This paper presents a new methodology for the automatic detection of defective regions of interest (d-ROI) in thermal images of composite materials. The images are acquired with pulsed thermography, and local histograms of oriented gradients are obtained by thermogram processing. This information is analyzed using a simple strategy to differentiate the material background from the defective areas. The procedure is independent of image contrast or enhancement; it does not require analysis of a complete sequence of images, nor does it involve heat transfer models or the extraction of nonuniform heating information. The methodology is tested with synthetic images of a carbon fiber-reinforced plastic sample, containing diameter/depth ratio defects with different values (between 150 and 0.56). The performance of the d-ROI detection method is validated using the area under the ROC curve (AUC) measure, generally obtaining a maximum average value of 0.949 with variations between 0.891 and 0.993 for all the defective depth and size conditions studied. In addition, this method is highly robust when detecting defects in 48.84% of the total number of images, as determined by the sequences analyzed with AUC values higher than 0.95. Outside the high detectability index range, the AUC performance increases abruptly and decays gradually. Recent literature proposes automatic detection of defects in thermograms yielding similar performances to those obtained with the proposed method; however, they require preprocessing of all the thermograms to improve image contrast and visibility and to attenuate the adverse effect of nonuniform heating, which affects the implementation complexity and the computational cost.

4.
J Ind Microbiol Biotechnol ; 42(1): 57-72, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25371290

RESUMO

Marine sediments from Newfoundland, Canada were explored for biotechnologically promising Actinobacteria using culture-independent and culture-dependent approaches. Culture-independent pyrosequencing analyses uncovered significant actinobacterial diversity (H'-2.45 to 3.76), although the taxonomic diversity of biotechnologically important actinomycetes could not be fully elucidated due to limited sampling depth. Assessment of culturable actinomycete diversity resulted in the isolation of 360 actinomycetes representing 59 operational taxonomic units, the majority of which (94 %) were Streptomyces. The biotechnological potential of actinomycetes from NL sediments was assessed by bioactivity and metabolomics-based screening of 32 representative isolates. Bioactivity was exhibited by 41 % of isolates, while 11 % exhibited unique chemical signatures in metabolomics screening. Chemical analysis of two isolates resulted in the isolation of the cytotoxic metabolite 1-isopentadecanoyl-3ß-D-glucopyranosyl-X-glycerol from Actinoalloteichus sp. 2L868 and sungsanpin from Streptomyces sp. 8LB7. These results demonstrate the potential for the discovery of novel bioactive metabolites from actinomycetes isolated from Atlantic Canadian marine sediments.


Assuntos
Actinobacteria/química , Actinobacteria/isolamento & purificação , Sedimentos Geológicos/microbiologia , Streptomyces/química , Actinobacteria/genética , Actinomycetales/química , Actinomycetales/genética , Actinomycetales/isolamento & purificação , Anti-Infecciosos/farmacologia , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Meios de Cultura/química , DNA Bacteriano/genética , Resistência Microbiana a Medicamentos , Fermentação , Humanos , Metabolômica , Terra Nova e Labrador , Peptídeos/farmacologia , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Streptomyces/genética , Streptomyces/isolamento & purificação
5.
Phys Rev E ; 106(4-1): 044114, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36397541

RESUMO

The magnetic properties and thermodynamical description of the Fe-Mn-Al ternary alloy are studied using the spin 1 antiferromagnetic Blume-Capel (BC) model by the pair approximation based on the Gibbs-Feymann-Bogoliubov inequality for the free energy. The values of the spin operator are +1 for ferromagnetic interaction (Fe-Fe), -1 for the antiferromagnetic one (Mn-Mn, Mn-Fe), and 0 for the magnetic diluter (corresponding to Al). The BC model with antiferromagnetic (AF) next-nearest-neighbor coupling better accurately fit the mean hyperfine field experimental data obtained by Mössbauer spectroscopy. Considering the crystalline field, the predicted temperature as a function of the Al concentration phase diagram, for the fcc lattice, from the numerical solution is remarkably good and significantly improves the traditional Ising and random-site Ising models.

6.
Heliyon ; 8(3): e09026, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35252619

RESUMO

Molecular dynamic (MD) calculations were performed to investigate the thermodynamic and structural properties of lead fluoride (PbF2) by using a proposed inter-ionic temperature-dependent potential. This potential allows calculating with high precision the linear thermal expansivity and the lattice parameter as a temperature function. In addition, the potential can be represented as a sum of two contributions, a temperature-independent potential added to another temperature-dependent potential, considered last as a correction justified by the one-dimensional Newtonian quantum equation. Two fitting regions were considered, the first region from 300 to 700 K and the other one from 700 to 900 K. These regions arise naturally due to the smooth and continuous transition that PbF2 undergoes until it reaches the superionic state and, allows us to model with high precision the anomaly in the dependence of the lattice parameter with the temperature of this material, a feature that until now under the molecular dynamic method has not been studied. These results are all in good agreement with the experimental measurements.

7.
Environ Sci Technol ; 45(4): 1219-27, 2011 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-21222455

RESUMO

Identifying drivers of deforestation in tropical biodiversity hotspots is critical to assess threats to particular ecosystems and species and proactively plan for conservation. We analyzed land cover change between 2002 and 2007 in the northern Andes, Chocó, and Amazon forests of Colombia, the largest producer of coca leaf for the global cocaine market, to quantify the impact of this illicit crop on forest dynamics, evaluate the effectiveness of protected areas in this context, and determine the effects of eradication on deforestation. Landscape-level analyses of forest conversion revealed that proximity to new coca plots and a greater proportion of an area planted with coca increased the probability of forest loss in southern Colombia, even after accounting for other covariates and spatial autocorrelation. We also showed that protected areas successfully reduced forest conversion in coca-growing regions. Neither eradication nor coca cultivation predicted deforestation rates across municipalities. Instead, the presence of new coca cultivation was an indicator of municipalities, where increasing population led to higher deforestation rates. We hypothesize that poor rural development underlies the relationship between population density and deforestation in coca-growing areas. Conservation in Colombia's vast forest frontier, which overlaps with its coca frontier, requires a mix of protected areas and strategic rural development to succeed.


Assuntos
Biodiversidade , Conservação dos Recursos Naturais , Coca , Cocaína , Colômbia , Ecossistema , Humanos , Densidade Demográfica , População Rural , Árvores , Clima Tropical
8.
Rehabilitacion (Madr) ; 55(4): 301-311, 2021.
Artigo em Espanhol | MEDLINE | ID: mdl-33875245

RESUMO

In the area of health there are scales that allow collecting and analyzing conditions objectively. Its validation process includes translation from another language, semantic adaptation, and its application to measure its validity and reliability in an environment other than the original one. The objective of this review was to identify the instruments validated in Hispanics America in the literature and to know the psychometric properties in the field of neurorehabilitation. An exploratory review was carried out in the PubMed, PeDro, Scholar, Science Direct and LILACS databases, using combinations with «evaluation¼, «physical therapy¼, «rehabilitation¼, «Neurology¼. Of the 18,355 records retrieved, 105 received a full title and abstract reading; where finally 25 were included in the qualitative synthesis and critically appreciated. It is concluded that the scales presented here have good psychometric characteristics that allow their adoption in clinical and therapeutic processes.


Assuntos
Reabilitação Neurológica , Hispânico ou Latino , Humanos , Psicometria , Reprodutibilidade dos Testes , Traduções
9.
J Med Primatol ; 39(3): 166-9, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20236218

RESUMO

Congenital aplasia of the hallux (big toe) was observed in seven adult and infant members of a free-ranging group of silvery marmosets (Mico argentatus) in the Alter do Chão savannah of central Amazonia. Apparently heritable, the condition was more common in males (80%) than females (50%) but was found in no other members of the population. Animals with the condition presented normal behaviour.


Assuntos
Callithrix/anormalidades , Deformidades Congênitas do Pé/veterinária , Hallux/anormalidades , Animais , Feminino , Masculino
10.
IEEE Trans Nanobioscience ; 19(2): 183-191, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31905141

RESUMO

La0.7 Sr0.3 MnO3 (LSMO) nanoparticles have been obtained via solution combustion synthesis (SCS) using urea and glycine as fuels. Also, La0.7 Sr0.27 Ca0.03 MnO3 (LSCMO) nanoparticles have been synthesized through solution combustion using urea as fuel. In this paper, the combustion process was carried out with a fuel to oxidant ratio giving fuel deficient conditions ( ). The thermal analysis (TGA) indicate that the organic residues from the urea-nitrates gel mixture are eliminated above 600 °C and the post-synthesis heat treatment yields the formation of the desired phase without impurities. The obtained phases were analyzed using X-ray diffraction. The infrared analysis confirms the purity of the samples obtained using urea. However, the sample obtained using glycine confirms the formation of SrCO3. The morphology was analyzed using a FE-SEM microscope, and it was found that the particles present a spherical shape with a mean size of around 45 nm in the selected samples. The samples' energy dispersive X-ray spectra show that the desired elements (La, Sr, Ca, Mn and O) are present in the nanoparticles. The measured zero field cooled (ZFC) and field cooled (FC) magnetizations were recorded from 4.5 to 380 K at 105 A/m to obtain their blocking and Curie temperatures. Moreover, the hysteresis loops measured at room temperature confirm the superparamagnetic behavior of the elaborated samples. According to the results obtained, these nanoparticles have interesting properties that make them candidates to explore not only for their potential in biomedical applications but also in refrigeration and magnetic storage devices.


Assuntos
Compostos de Cálcio , Lantânio/química , Manganês/química , Óxidos , Titânio , Ureia/química , Compostos de Cálcio/síntese química , Compostos de Cálcio/química , Técnicas de Química Sintética/métodos , Temperatura Alta , Nanopartículas de Magnetita/química , Óxidos/síntese química , Óxidos/química , Estrôncio/química , Titânio/química
11.
Prog Neuropsychopharmacol Biol Psychiatry ; 33(2): 214-9, 2009 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-19059449

RESUMO

Bipolar disorder (BPD) and schizophrenia (SCZ) are severe disorders representing an enormous social, familiar and individual burden, being SCZ the most disabling psychiatric disorder characterized by psychosis and cognitive impairment. It is well known that SCZ and BPD are associated with abnormalities in dopamine signaling pathway. Recent data in the literature have demonstrated altered expression levels of some proteins involved in the modulation of this pathway in both brain and peripheral tissues. It was shown that protein and mRNA levels of dopamine and cAMP regulated phosphoprotein (DARPP-32) were downregulated in dorsolateral prefrontal cortex (DLPFC) of patients with SCZ or BPD when compared to controls. Due to the difficulty to access brain tissue and the absence of objective laboratory tests for bio-markers, we measured DARPP-32 expression in blood cell sub-populations (CD4+ T lymphocytes, CD56+ NK cells, CD19+ B lymphocytes and CD14+ monocytes) taking advantage of the close relation of nervous and immune systems. Using flow cytometry as the analytical method, our results have shown that the DARPP-32 expression was diminished in CD4+ T lymphocytes, CD19+ B lymphocytes and CD14+ monocytes of BPD patients and was also decreased in CD4+ T lymphocytes and CD56+ NK cells of SCZ patients. These results showed that DARPP-32 expression in immune cells agrees with reports of reduced DARPP-32 protein in the DLPFC of BPD or SCZ patients. Our data suggest that DARPP-32 expression in PBMC could be used as a source of bio-markers to help in the treatment response of neuropsychiatry disorders as a window to the changes in the brain of those patients.


Assuntos
Transtorno Bipolar/metabolismo , Fosfoproteína 32 Regulada por cAMP e Dopamina/biossíntese , Leucócitos/metabolismo , Esquizofrenia/metabolismo , Adulto , Idoso , Biomarcadores , Linfócitos T CD4-Positivos/metabolismo , Feminino , Citometria de Fluxo , Humanos , Células Matadoras Naturais/metabolismo , Linfócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Escalas de Graduação Psiquiátrica
12.
Prog Neuropsychopharmacol Biol Psychiatry ; 33(2): 229-34, 2009 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-19091302

RESUMO

Schizophrenia (SCZ) and bipolar disorder (BPD) are severe illnesses representing an enormous social, familiar and individual burden that affect 1% of the population world-wide. Several evidences indicate abnormalities of the dopamine system in both SCZ and BPD. Neuronal calcium sensor-1 (NCS-1) is a protein that has many functions in neurotransmission such as inhibition of dopamine D(2) receptor desensitization, regulation of ionic channels and enhancement of exocytosis of neurotransmitters. In addition, NCS-1 protein expression and mRNA levels were found increased in pre-frontal cortex (PFC) of SCZ and BPD patients. NCS-1 expression in neural and neuroendocrine cells is well documented and, recently, it was shown that NCS-1 is also expressed in mast cells and neutrophils. NCS-1 has important functions in mast cells since it stimulates Fc epsilon RI-triggered exocytosis and the release of arachidonic acid metabolites. Then, due to the known close relation between the nervous and immune systems, we sought to investigate the NCS-1 expression in lymphocytes and monocytes (CD4+ T lymphocytes, CD56+ NK cells, CD19+ B lymphocytes and CD14+ monocytes) of SCZ and BPD patients. Using flow cytometry, our results have shown that NCS-1 expression was diminished in CD4+T lymphocytes, CD19+ B lymphocytes and CD14+ monocytes of BPD patients and also decreased in CD4+ T lymphocytes and CD56+ NK cells of SCZ patients. Results suggest that immune cells might be a cellular model for studies with SCZ and BPD patients considering NCS-1 functions. Efforts need to be done to investigate the motive of the decreased percentage of immune cells expressing NCS-1 in patients with SCZ and BPD.


Assuntos
Transtorno Bipolar/metabolismo , Leucócitos/metabolismo , Proteínas Sensoras de Cálcio Neuronal/metabolismo , Neuropeptídeos/metabolismo , Esquizofrenia/metabolismo , Adulto , Idoso , Antígenos CD19/metabolismo , Linfócitos B/metabolismo , Biomarcadores , Linfócitos T CD4-Positivos/metabolismo , Antígeno CD56/metabolismo , Feminino , Citometria de Fluxo , Humanos , Células Matadoras Naturais/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Masculino , Pessoa de Meia-Idade , Monócitos/metabolismo , Escalas de Graduação Psiquiátrica
13.
Data Brief ; 26: 104404, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31867413

RESUMO

Using the ac-calorimetry technique and the electric modulus formalism for analysis of ionic conductivity relaxation in crystalline γ -RbAg4I5, close to the γ to ß phase transition at 120 K, the temperature derivative of microscopic interaction energy for a single-mobile ion is proportional to the specific heat. The two different experimental techniques show that cooperative behavior drives the phase transition at 120 K (obey the same mechanism).

14.
J Crit Care ; 51: 204-212, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30903936

RESUMO

PURPOSE: During sepsis and mechanical ventilation oxidative stress is generated by endothelial and inflammatory lung cells. Our main objective was to study pulmonary NO (nitric oxide) production and nitroxidative stress in mechanically-ventilated septic patients. METHODS: We study 69 mechanically ventilated patients, 36 with sepsis and 33 without sepsis within the first 48 h of ICU admission compared with 33 mechanically ventilated patients without sepsis (MV) plus eight operating room patients without lung disease served as control healthy group (ORCG). Nitrite plus nitrate (NOx-), 3-nitrotyrosine and malondialdehyde (MDA) in bronchoalveolar lavage fluid (BALF) were analyzed. RESULTS: BALF NOx-, BALF 3-nitrotyrosine, BALF MDA, and plasma NOx- were higher in the Sepsis than in MV patients (all p < .05). Both SG and MV patients had higher BALF NOx- than the healthy control group (p < .001). In the Sepsis patients, the ICU non-survivors had higher levels of BALF NOx- than ICU survivors 80(70-127) µM versus 31(15-47) µM, p < .001. CONCLUSIONS: We conclude that during early phases of sepsis there is an enhanced lung nitroxidative stress due to an increase of NO production leading to secondary NO-derived oxidants, which promote protein nitration and lipid peroxidation.


Assuntos
Óxido Nítrico/metabolismo , Estresse Oxidativo/fisiologia , Respiração Artificial/efeitos adversos , Insuficiência Respiratória , Sepse/complicações , Adulto , Idoso , Líquido da Lavagem Broncoalveolar , Estudos de Casos e Controles , Feminino , Humanos , Masculino , Malondialdeído/metabolismo , Pessoa de Meia-Idade , Projetos Piloto , Insuficiência Respiratória/metabolismo , Insuficiência Respiratória/terapia , Sepse/metabolismo
15.
J Comp Pathol ; 173: 49-57, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31812173

RESUMO

Malignant melanomas (MMs) represent 7% of all malignant neoplasms in dogs. Oral melanocytic neoplasms are often malignant and associated with poor prognosis. There are no universally accepted prognostic markers for canine oral melanoma. Galectin (Gal)-3 is a prognostic marker for human neoplasms such as thyroid, gastric, colorectal and prostate cancers. The protein is related to processes that favour cancer progression, such as angiogenesis, proliferation and apoptosis. The aim of the present study was to characterize the immunohistochemical expression of Gal-3 in canine oral melanomas and to compare it with post-surgical survival, the expression of apoptosis-related proteins and other known prognostic tools. Twenty-seven samples of canine oral melanomas were evaluated for Gal-3, B-cell lymphoma (BCL) 2, caspase (CASP) 3 and Ki67 expression, mitotic index and degree of nuclear atypia. Gal-3 cytoplasmic positivity was correlated positively, while nuclear positivity was correlated negatively, with survival. The intensity of BCL2 labelling was also correlated positively with Gal-3 cytoplasmic positivity. Higher nuclear atypia was observed in dogs with melanoma that died due to the tumour, as well as in dogs that survived for <1 year after surgery. We have confirmed the importance of nuclear atypia for MMs and suggest that Gal-3 is a valuable prognostic indicator for this neoplasm. More in-depth studies are needed to unveil Gal-3 functions in canine MMs using larger sample sizes.


Assuntos
Biomarcadores Tumorais/metabolismo , Doenças do Cão , Galectina 3/metabolismo , Melanoma/veterinária , Neoplasias Bucais/veterinária , Animais , Biomarcadores Tumorais/análise , Doenças do Cão/metabolismo , Doenças do Cão/patologia , Cães , Galectina 3/análise
16.
Clin Exp Immunol ; 154(3): 346-52, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19037919

RESUMO

There is common agreement that fibromyalgia (FM) is an extremely heterogeneous entity. Patients differ in their clinical symptoms, endocrine and immune parameters. In this study we evaluated endocrine and immunological features of distinct subsets of FM patients. In contrast to previous attempts to identify subsets of FM patients, based solely on their psychological and cognitive features, herein we propose to separate FM patients by genetic features. Allelic expression of the polymorphic promoter region of the serotonin transporter (5-HTTLPR) was analysed as a relevant genetic factor for FM. Seventy-five patients meeting the American College of Rheumatology criteria and 27 healthy age-matched controls participated in this study. All controls and FM patients were submitted to genotyping of 5-HTTLPR. Twenty-seven FM patients, who were able to discontinue hypnotic, sedative or psychotropic prescription medications for at least 2 weeks, were then subdivided into L (homozygote LL) or S groups (genotypes LS and SS). They were evaluated for salivary cortisol levels, absolute number of leucocyte subpopulations, including natural killer (NK) cells and activated T and B lymphocytes. Both groups presented decreased cortisol levels, more intense in the L group, increased all B lymphocytes subsets and reduced CD4+CD25high T lymphocytes. The L group had increased CD4+CD25low activated T lymphocytes, while the S group displayed elevated CD4+ human leucocyte antigen D-related (HLA-DR)+ activated T lymphocytes and decreased NK cells. We demonstrate that genetic factors may help to identify FM individuals with differentially altered frequencies of immune cells.


Assuntos
Fibromialgia/genética , Fibromialgia/imunologia , Adulto , Subpopulações de Linfócitos B/imunologia , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Hidrocortisona/metabolismo , Células Matadoras Naturais/imunologia , Contagem de Leucócitos , Ativação Linfocitária/imunologia , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/genética , Saliva/metabolismo , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Subpopulações de Linfócitos T/imunologia
18.
Am J Med Genet B Neuropsychiatr Genet ; 147B(1): 114-6, 2008 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-17579356

RESUMO

The serotonin transporter gene has a 44 bp insertion/deletion polymorphism within the promoter region (5-HTTLPR) with two allelic forms, the long (L) and the short (S) variants. Association between the low-activity S variant and bipolar disorder (BPD) has been shown but its replication has not been consistent. It has also been described as an association between the S allele and suicidal behavior. Since suicidal behavior is a rather frequent event in BPD, an important question is whether suicidality, instead of bipolarity itself, could be related to S allele. We assessed 351 subjects (167 bipolar inpatients and 184 healthy controls). Diagnosis was conducted by a psychiatrist using a structured interview (MINI-PLUS), according to DSM-IV criteria. Suicidal behavior was assessed using a semi-structured instrument and a review of medical records. Genotyping of the 5-HTTLPR was performed using PCR. There were 77 patients with a history of previous suicide attempts. Bipolar patients and healthy controls showed comparable genotypic and allelic frequencies. Patients carrying the S allele made violent suicide attempts more frequently (chi(2) = 20.2; P = 0.0001) and made more suicide attempts (t = 2.6; P = 0.01). We were able to show an association between the S allele and suicidal behavior but not with BPD. Our data suggest that a phenotypic stratification, taking into account the suicidal behavior history, is of pivotal importance when performing association studies between BPD and 5-HTTLPR genotypes, which could explain previous contradictory results.


Assuntos
Transtorno Bipolar/genética , Predisposição Genética para Doença , Polimorfismo Genético , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Tentativa de Suicídio , Adulto , Alelos , Transtorno Bipolar/diagnóstico , Feminino , Ligação Genética , Genótipo , Humanos , Masculino , Regiões Promotoras Genéticas
19.
Clin Pediatr (Phila) ; 46(1): 59-63, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17164511

RESUMO

The recto-sigmoid index on barium enema may aid in the diagnosis of Hirschsprung's disease. However, data on its reliability in different age groups are sparse. The recto-sigmoid index and transitional zone were evaluated blindly in 107 patients with diagnostic rectal suction biopsies. Patients were divided into 3 groups: neonates, infants older than 1 month, and children. The recto-sigmoid index and transitional zone agreed with the histopathologic diagnosis in 79% and 87% of the cases, respectively. Their negative predictive values reached clinical significance in infants and children but not in neonates. Their positive predictive values were not significant in any age group. The recto-sigmoid index identified 4 patients with recto-sigmoid Hirschsprung's disease whose diagnosis was missed by evaluating the transitional zone alone.


Assuntos
Sulfato de Bário , Enema , Doença de Hirschsprung/diagnóstico por imagem , Adolescente , Adulto , Biópsia , Criança , Pré-Escolar , Colo Sigmoide/diagnóstico por imagem , Colo Sigmoide/patologia , Intervalos de Confiança , Meios de Contraste , Diagnóstico Diferencial , Feminino , Doença de Hirschsprung/patologia , Humanos , Lactente , Recém-Nascido , Masculino , Valor Preditivo dos Testes , Radiografia , Reto/diagnóstico por imagem , Reto/patologia , Estudos Retrospectivos , Sensibilidade e Especificidade , Sucção
20.
Genes Brain Behav ; 5(4): 340-5, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16716203

RESUMO

According to WHO, suicide accounts for about 1,000,000 deaths worldwide every year. In view of these dramatic data, several studies have tried to identify possible biological mechanisms and markers of suicide. Genes encoding for proteins involved in the serotonergic transmission are major candidates in association studies of suicidal behavior. The gene that codes for tryptophan hydroxylase (TPH), the rate-limiting enzyme in the biosynthesis of serotonin, is one of these candidates. Two polymorphisms in intron 7 of this gene (A218C and A779C) have been described, but their role in suicidal behavior remains uncertain. TPH A218C polymorphism was analyzed in a sample of 248 psychiatric patients and 63 healthy controls. In addition, at least one close relative member was interviewed to assess family suicidal behavior history. Our research confirmed that a positive history of suicide attempts in a family member is associated with the chance of an individual to attempt suicide. Furthermore, we demonstrated that familial suicide attempts are more lethal and frequently more violent. We were not able to find significant differences of the TPH genotype frequencies between patients and controls. The TPH A218C genotypes were not associated with a history of suicide attempt and the lethality of the most lethal lifetime suicide attempt and suicide attempt method. The authors conclude that the A218C polymorphism of the TPH gene may not be a susceptibility factor for suicidal behavior in this group of psychiatric patients but confirm that a family suicidal behavior history increases the proband's suicide attempt risk.


Assuntos
Transtornos Mentais/genética , Tentativa de Suicídio/estatística & dados numéricos , Suicídio , Triptofano Hidroxilase/genética , Adulto , Alcoolismo/genética , Alcoolismo/psicologia , Brasil , Estudos de Casos e Controles , Transtorno Depressivo Maior/genética , Transtorno Depressivo Maior/psicologia , Saúde da Família , Feminino , Frequência do Gene , Genótipo , Humanos , Masculino , Transtornos Mentais/psicologia , Pessoa de Meia-Idade , Linhagem , Polimorfismo Genético/genética , Valores de Referência , Esquizofrenia/genética , Psicologia do Esquizofrênico , Suicídio/psicologia , Tentativa de Suicídio/psicologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA