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1.
Mol Psychiatry ; 23(2): 422-433, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-27843151

RESUMO

The lack of reliable measures of alcohol intake is a major obstacle to the diagnosis and treatment of alcohol-related diseases. Epigenetic modifications such as DNA methylation may provide novel biomarkers of alcohol use. To examine this possibility, we performed an epigenome-wide association study of methylation of cytosine-phosphate-guanine dinucleotide (CpG) sites in relation to alcohol intake in 13 population-based cohorts (ntotal=13 317; 54% women; mean age across cohorts 42-76 years) using whole blood (9643 European and 2423 African ancestries) or monocyte-derived DNA (588 European, 263 African and 400 Hispanic ancestry) samples. We performed meta-analysis and variable selection in whole-blood samples of people of European ancestry (n=6926) and identified 144 CpGs that provided substantial discrimination (area under the curve=0.90-0.99) for current heavy alcohol intake (⩾42 g per day in men and ⩾28 g per day in women) in four replication cohorts. The ancestry-stratified meta-analysis in whole blood identified 328 (9643 European ancestry samples) and 165 (2423 African ancestry samples) alcohol-related CpGs at Bonferroni-adjusted P<1 × 10-7. Analysis of the monocyte-derived DNA (n=1251) identified 62 alcohol-related CpGs at P<1 × 10-7. In whole-blood samples of people of European ancestry, we detected differential methylation in two neurotransmitter receptor genes, the γ-Aminobutyric acid-A receptor delta and γ-aminobutyric acid B receptor subunit 1; their differential methylation was associated with expression levels of a number of genes involved in immune function. In conclusion, we have identified a robust alcohol-related DNA methylation signature and shown the potential utility of DNA methylation as a clinically useful diagnostic test to detect current heavy alcohol consumption.


Assuntos
Consumo de Bebidas Alcoólicas/genética , Transtornos Relacionados ao Uso de Álcool/genética , Metilação de DNA/efeitos dos fármacos , Adulto , Idoso , Consumo de Bebidas Alcoólicas/metabolismo , Transtornos Relacionados ao Uso de Álcool/metabolismo , Biomarcadores/sangue , População Negra/genética , Ilhas de CpG/genética , Epigênese Genética , Etanol/sangue , Etanol/metabolismo , Feminino , Estudo de Associação Genômica Ampla , Humanos , Masculino , Pessoa de Meia-Idade , População Branca/genética
2.
Br J Cancer ; 108(10): 2178-85, 2013 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-23571737

RESUMO

BACKGROUND: Most of the heritable risk of glioma is presently unaccounted for by mutations in known genes. In addition to rare inactivating germline mutations in TP53 causing glioma in the context of the Li-Fraumeni syndrome, polymorphic variation in TP53 may also contribute to the risk of developing glioma. METHODS: To comprehensively evaluate the impact of variation in TP53 on risk, we analysed 23 tagSNPs and imputed 2377 unobserved genotypes in four series totaling 4147 glioma cases and 7435 controls. RESULTS: The strongest validated association signal was shown by the imputed single-nucleotide polymorphism (SNP) rs78378222 (P=6.86 × 10(-24), minor allele frequency ~0.013). Confirmatory genotyping confirmed the high quality of the imputation. The association between rs78378222 and risk was seen for both glioblastoma multiforme (GBM) and non-GBM tumours. We comprehensively examined the relationship between rs78378222 and overall survival in two of the case series totaling 1699 individuals. Despite employing statistical tests sensitive to the detection of differences in early survival, no association was shown. CONCLUSION: Our data provided strong validation of rs78378222 as a risk factor for glioma but do not support the tenet that the polymorphism being a clinically useful prognostic marker. Acquired TP53 inactivation is a common feature of glioma. As rs78378222 changes the polyadenylation signal of TP53 leading to impaired 3'-end processing of TP53 mRNA, the SNP has strong plausibility for being directly functional contributing to the aetiological basis of glioma.


Assuntos
Neoplasias Encefálicas/genética , Glioma/genética , Penetrância , Polimorfismo de Nucleotídeo Único , Proteína Supressora de Tumor p53/genética , Neoplasias Encefálicas/epidemiologia , Estudos de Casos e Controles , Europa (Continente)/epidemiologia , Feminino , Frequência do Gene , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Glioma/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/fisiologia , Processamento de Terminações 3' de RNA/genética , Proteína Supressora de Tumor p53/fisiologia , Estados Unidos/epidemiologia
3.
Allergy ; 68(5): 629-36, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23452035

RESUMO

BACKGROUND: Genome-wide association studies (GWAS) have identified many risk loci for asthma, but effect sizes are small, and in most cases, the biological mechanisms are unclear. Targeted metabolite quantification that provides information about a whole range of pathways of intermediary metabolism can help to identify biomarkers and investigate disease mechanisms. Combining genetic and metabolic information can aid in characterizing genetic association signals with high resolution. This work aimed to investigate the interrelation of current asthma, candidate asthma risk alleles and a panel of metabolites. METHODS: We investigated 151 metabolites, quantified by targeted mass spectrometry, in fasting serum of asthmatic and nonasthmatic individuals from the population-based KORA F4 study (N = 2925). In addition, we analysed effects of single-nucleotide polymorphisms (SNPs) at 24 asthma risk loci on these metabolites. RESULTS: Increased levels of various phosphatidylcholines and decreased levels of various lyso-phosphatidylcholines were associated with asthma. Likewise, asthma risk alleles from the PDED3 and MED24 genes at the asthma susceptibility locus 17q21 were associated with increased concentrations of various phosphatidylcholines with consistent effect directions. CONCLUSIONS: Our study demonstrated the potential of metabolomics to infer asthma-related biomarkers by the identification of potentially deregulated phospholipids that associate with asthma and asthma risk alleles.


Assuntos
Asma/genética , Asma/metabolismo , Perfilação da Expressão Gênica , Metaboloma , Fosfatidilcolinas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Estudos Transversais , Feminino , Loci Gênicos , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Polimorfismo de Nucleotídeo Único
4.
J Exp Med ; 192(11): 1677-84, 2000 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-11104810

RESUMO

A proliferation-inducing ligand (APRIL) is a ligand of the tumor necrosis factor (TNF) family that stimulates tumor cell growth in vitro and in vivo. Expression of APRIL is highly upregulated in many tumors including colon and prostate carcinomas. Here we identify B cell maturation antigen (BCMA) and transmembrane activator and calcium modulator and cyclophilin ligand (CAML) interactor (TACI), two predicted members of the TNF receptor family, as receptors for APRIL. APRIL binds BCMA with higher affinity than TACI. A soluble form of BCMA, which inhibits the proliferative activity of APRIL in vitro, decreases tumor cell proliferation in nude mice. Growth of HT29 colon carcinoma cells is blocked when mice are treated once per week with the soluble receptor. These results suggest an important role for APRIL in tumorigenesis and point towards a novel anticancer strategy.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Linfócitos B/fisiologia , Transformação Celular Neoplásica , Proteínas de Membrana/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Células 3T3 , Animais , Fator Ativador de Células B , Antígeno de Maturação de Linfócitos B , Proteínas de Transporte/metabolismo , Divisão Celular , Linhagem Celular Transformada , Células HT29 , Humanos , Proteínas de Membrana/genética , Camundongos , Camundongos Nus , Neoplasias/terapia , Receptores do Fator de Necrose Tumoral/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Solubilidade , Proteína Transmembrana Ativadora e Interagente do CAML , Células Tumorais Cultivadas , Membro 13 da Superfamília de Ligantes de Fatores de Necrose Tumoral , Fator de Necrose Tumoral alfa/genética
5.
Clin Genet ; 78(5): 490-4, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20412113

RESUMO

Recently, PALB2 was reported to be a new pancreatic cancer susceptibility gene as determined by exomic sequencing, as truncating PALB2 mutations were identified in 3 of 96 American patients with familial pancreatic cancer (FPC). Representing the European Registry of Hereditary Pancreatitis and Familial Pancreatic Cancer (EUROPAC) and the German National Case Collection for Familial Pancreatic Cancer (FaPaCa), we evaluated whether truncating mutations could also be detected in European FPC families. We have directly sequenced the 13 exons of the PALB2 gene in affected index patients of 81 FPC families. An index patient was defined as the first medically identified patient, stimulating investigation of other members of the family to discover a possible genetic factor. None of these patients carried a BRCA2 mutation. We identified three (3.7%) truncating PALB2 mutations, each producing different stop codons: R414X, 508-9delAG and 3116delA. Interestingly, each of these three families also had a history of breast cancer. Therefore, PALB2 mutations might be causative for FPC in a small subset of European families, especially in those with an additional occurrence of breast cancer.


Assuntos
Proteínas Nucleares/genética , Neoplasias Pancreáticas/genética , Proteínas Supressoras de Tumor/genética , População Branca/genética , Adulto , Neoplasias da Mama/complicações , Neoplasias da Mama/genética , Proteína do Grupo de Complementação N da Anemia de Fanconi , Feminino , Mutação em Linhagem Germinativa , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/complicações
6.
Int Endod J ; 43(9): 808-17, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20796049

RESUMO

AIM: To evaluate the accuracy of four electronic apex locators (EAL) in the apical region (0-3 mm short of the foramen) and to compare the precision of the readings on the display with the real position of the file in the root canal. METHODOLOGY: Twenty single-rooted extracted teeth with round root canals were used. The canal orifices were preflared, and the length to the major foramen was determined visually under a microscope. Canals were enlarged, so that a size 15 file fitted well inside the canal. Teeth were mounted in acrylic test tubes filled with physiologic saline solution. Electronic length was determined in the region between the major foramen and 3 mm short of it in 0.5 mm steps with the Dentaport ZX, Root ZX mini, Elements Diagnostic Unit and Apex Locator and Raypex 5 using files of size 10 and size 15. The data were analysed using linear regression between true length and EAL reading, Bland-Altman plots and nonparametric tests at a significance level of alpha = 0.05. RESULTS: The major foramen was detected by all EALs. With a measurement file positioned directly at the major foramen, meter readings were equivalent to a position 0.01-0.38 mm away. For the Dentaport ZX, a better accuracy using the size 15 file for the area 0-1.5 mm short of the apex was found. The differences in measurements between the two files were smaller for the other EALs. In linear regression, a good linearity for Dentaport ZX and Root ZX mini and moderate linearity for Elements Diagnostic Unit and Apex Locator and Raypex 5 were found. The slope of the measurement curve was too low (0.37-0.57) for the Raypex 5 and almost optimal for the Dentaport ZX (1.01-1.05). The Root ZX mini and the Elements Obturation Unit produced lower slope values and especially the Elements Obturation Unit revealed much higher SDs at the different measurement levels. CONCLUSION: Amongst the four EALs, the Dentaport ZX and Root ZX mini had the best agreement between true lengths and meter readings. For the Raypex 5, an interpretation of the colour-coded zones as distance to the foramen cannot be recommended and might lead to erroneous interpretations.


Assuntos
Cavidade Pulpar/anatomia & histologia , Odontometria/instrumentação , Ápice Dentário/anatomia & histologia , Equipamentos e Provisões Elétricas , Desenho de Equipamento , Humanos , Teste de Materiais , Microscopia/instrumentação , Odontometria/estatística & dados numéricos , Preparo de Canal Radicular/instrumentação
7.
Pediatr Surg Int ; 26(7): 697-702, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20490812

RESUMO

BACKGROUND: The diagnosis of acute appendicitis in pediatric patients is difficult. There are patients with positive ultrasonography without clinical or histological confirmation of acute appendicitis. It is essential to recognise these patients to avoid unnecessary surgery. METHODS: During 1 year, we compared the patients with 'false-positive' ultrasonography with those with 'true-positive' and those with 'true-negative' ultrasonography. RESULTS: Eighty-two patients were admitted to our inpatient ward for suspected appendicitis. Ultrasonography was performed on 68 patients. In sixteen cases, the ultrasonography showed typical signs of acute appendicitis though the patients turned out to be negative for acute appendicitis either by an observation period (n = 13) or by negative histology (n = 3). We could not find any significant differences between the groups in terms of age, gender or laboratory inflammation markers, though the latter tended to be elevated in patients with confirmed appendicitis. CONCLUSIONS: There are patients with clearly visible typical signs of acute appendicitis that do not need surgery and cannot be distinguished from others by age, gender or laboratory values. In conclusion, the clinical presentation still is the determining indicator for need of surgery. The underlying cause of the visible changes of the appendiceal area remains unclear, but there are several presumptions.


Assuntos
Apendicite/diagnóstico por imagem , Apêndice/diagnóstico por imagem , Doença Aguda , Adolescente , Apendicite/cirurgia , Criança , Pré-Escolar , Diagnóstico Diferencial , Reações Falso-Positivas , Feminino , Humanos , Masculino , Ultrassonografia , Procedimentos Desnecessários
8.
Science ; 293(5537): 2108-11, 2001 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-11509692

RESUMO

B cell homeostasis has been shown to critically depend on BAFF, the B cell activation factor from the tumor necrosis factor (TNF) family. Although BAFF is already known to bind two receptors, BCMA and TACI, we have identified a third receptor for BAFF that we have termed BAFF-R. BAFF-R binding appears to be highly specific for BAFF, suggesting a unique role for this ligand-receptor interaction. Consistent with this, the BAFF-R locus is disrupted in A/WySnJ mice, which display a B cell phenotype qualitatively similar to that of the BAFF-deficient mice. Thus, BAFF-R appears to be the principal receptor for BAFF-mediated mature B cell survival.


Assuntos
Linfócitos B/fisiologia , Proteínas de Membrana/metabolismo , Receptores do Fator de Necrose Tumoral/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Sequência de Aminoácidos , Animais , Fator Ativador de Células B , Receptor do Fator Ativador de Células B , Antígeno de Maturação de Linfócitos B , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linhagem Celular , Mapeamento Cromossômico , Cromossomos Humanos Par 22 , Clonagem Molecular , Homeostase , Humanos , Ligantes , Tecido Linfoide/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos A , Camundongos Endogâmicos C57BL , Dados de Sequência Molecular , RNA Mensageiro/química , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores do Fator de Necrose Tumoral/química , Receptores do Fator de Necrose Tumoral/genética , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais , Transfecção , Proteína Transmembrana Ativadora e Interagente do CAML
9.
Gigascience ; 7(12)2018 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30496450

RESUMO

Background: Genome-wide association studies have identified hundreds of loci that influence a wide variety of complex human traits; however, little is known regarding the biological mechanism of action of these loci. The recent accumulation of functional genomics ("omics"), including metabolomics data, has created new opportunities for studying the functional role of specific changes in the genome. Functional genomic data are characterized by their high dimensionality, the presence of (strong) statistical dependency between traits, and, potentially, complex genetic control. Therefore, the analysis of such data requires specific statistical genetics methods. Results: To facilitate our understanding of the genetic control of omics phenotypes, we propose a trait-centered, network-based conditional genetic association (cGAS) approach for identifying the direct effects of genetic variants on omics-based traits. For each trait of interest, we selected from a biological network a set of other traits to be used as covariates in the cGAS. The network can be reconstructed either from biological pathway databases (a mechanistic approach) or directly from the data, using a Gaussian graphical model applied to the metabolome (a data-driven approach). We derived mathematical expressions that allow comparison of the power of univariate analyses with conditional genetic association analyses. We then tested our approach using data from a population-based Cooperative Health Research in the region of Augsburg (KORA) study (n = 1,784 subjects, 1.7 million single-nucleotide polymorphisms) with measured data for 151 metabolites. Conclusions: We found that compared to single-trait analysis, performing a genetic association analysis that includes biologically relevant covariates can either gain or lose power, depending on specific pleiotropic scenarios, for which we provide empirical examples. In the context of analyzed metabolomics data, the mechanistic network approach had more power compared to the data-driven approach. Nevertheless, we believe that our analysis shows that neither a prior-knowledge-only approach nor a phenotypic-data-only approach is optimal, and we discuss possibilities for improvement.


Assuntos
Estudo de Associação Genômica Ampla , Redes e Vias Metabólicas/genética , Metaboloma/genética , Metabolômica/métodos , Algoritmos , Loci Gênicos , Genótipo , Humanos , Fenótipo , Polimorfismo de Nucleotídeo Único
10.
Leukemia ; 20(8): 1422-9, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16738692

RESUMO

Deletions of chromosome 6q have been reported in several hematological malignancies, but data are not conclusive regarding their biological and prognostic impact. Therefore, we focused on pediatric patients diagnosed with T-cell lymphoblastic lymphoma (T-LBL) treated uniformly according to the NHL-BFM95 protocol. We used loss-of-heterozygosity (LOH) analysis of 25 microsatellite markers located on chromosome 6q14-q24. Fragment-length analysis was performed on ABI-PRISM3100 Genetic-Analyzer. Eligibility criterion was > or =3 informative markers. Between April 1995 and March 2003, 185 T-LBL patients were treated according to the NHL-BFM95 protocol. Five-year event-free (EFS) and disease-free survival (DFS) were 79+/-3 and 87+/-3% (median follow-up 4.7 [1.2-10.1] years). Sixty-one patients were evaluable for LOH analysis, including 18 out of 23 patients with relapse. EFS and DFS were 67+/-6 and 69+/-6% for these 61 patients. Testing of 853 markers in the 61 patients identified the presence of LOH in 19 patients (31%): 13 of the 18 relapse patients and five of the 41 in complete remission (odds ratio 18.7, 95% confidence interval 4.7-75.3). One LOH-positive patient died from treatment-related toxicity. We conclude that LOH on chromosome 6q14-q24 may have conferred a high risk of relapse on our group of children with T-LBL treated according to the NHL-BFM95 protocol.


Assuntos
Cromossomos Humanos Par 6 , Leucemia-Linfoma de Células T do Adulto/genética , Perda de Heterozigosidade , Adolescente , Criança , Intervalo Livre de Doença , Feminino , Humanos , Leucemia-Linfoma de Células T do Adulto/mortalidade , Masculino
11.
Structure ; 9(4): 321-9, 2001 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-11525169

RESUMO

BACKGROUND: CD40 ligand (CD40L or CD154), a member of the tumor necrosis factor (TNF) family, plays a critical role in both humoral and cellular immune responses and has been implicated in biological pathways involving epithelial cells, fibroblasts, and platelets. Such a pathway is T cell-mediated B cell activation, a process that occurs through the interaction of CD40L with CD40 receptor expressed on B cells. It results in various B cell responses, including immunoglobulin isotype switching and B cell differentiation and proliferation. These responses can be inhibited by the monoclonal antibody 5c8, which binds with high affinity to CD40L. RESULTS: To understand the structural basis of the inhibition, we determined the crystal structure of the complex of the extracellular domain of CD40L and the Fab fragment of humanized 5c8 antibody. The structure shows that the complex has the shape of a three-bladed propeller with three Fab fragments bound symmetrically to a CD40L homotrimer. To further study the nature of the antibody-antigen interface, we assessed the ability of 23 site-directed mutants of CD40L to bind to 5c8 and CD40 and analyzed the results in the context of the crystal structure. Finally, we observed via confocal microscopy that 5c8 binding to CD40L on the cell surface results in the formation of patches of clustered complexes. CONCLUSIONS: The structure reveals that 5c8 neutralizes CD40L function by sterically blocking CD40 binding. The antigenic epitope is localized in a region of the surface that is likely to be structurally perturbed as a result of genetic mutations that cause hyper-IgM syndrome. The symmetric trimeric arrangement of the Fab fragments in the complex results in a geometry that facilitates the formation of large clusters of complexes on the cell surface.


Assuntos
Ligante de CD40/química , Ligante de CD40/imunologia , Fragmentos Fab das Imunoglobulinas/química , Fragmentos Fab das Imunoglobulinas/imunologia , Sequência de Aminoácidos , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Afinidade de Anticorpos , Sítios de Ligação de Anticorpos , Ligante de CD40/genética , Cristalografia por Raios X , Epitopos/química , Epitopos/genética , Epitopos/imunologia , Humanos , Camundongos , Microscopia Confocal , Modelos Moleculares , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Testes de Neutralização , Conformação Proteica , Eletricidade Estática
12.
Ann Cardiol Angeiol (Paris) ; 54(6): 332-8, 2005 Nov.
Artigo em Francês | MEDLINE | ID: mdl-17183829

RESUMO

Acute type A aortic dissection is a surgical emergency. Treatment is based on dissected ascending aortic replacement and correction of an associated aortic insufficiency. Catheterization of the axillary artery, open distal anastomosis and systematic resection of the intimal tear are the main surgical evolutions of the last years. They allowed to significantly reduce intraoperative mortality rate particularly due to bleeding. Thirty days mortality rate of operated aortic dissection is about 20 to 30%. Visceral malperfusion syndromes induced by aortic dissection represent an important cause of postoperative death. An early diagnosis and treatment appears necessary. Thoracoabdominal CT scan allows understanding mechanisms inducing malperfusion. Aortography and an emergency endovascular procedure allow restoring arterial blood flow before renal or mesenteric irreversible ischemia. Collaboration between radiologist, anesthesiologist and surgeon is necessary to optimize survival of acute type A aortic dissection.


Assuntos
Aneurisma da Aorta Torácica/cirurgia , Dissecção Aórtica/cirurgia , Isquemia/cirurgia , Rim/irrigação sanguínea , Mesentério/irrigação sanguínea , Reperfusão/métodos , Doença Aguda , Anastomose Cirúrgica , Dissecção Aórtica/complicações , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/mortalidade , Aneurisma da Aorta Torácica/complicações , Aneurisma da Aorta Torácica/diagnóstico por imagem , Aneurisma da Aorta Torácica/mortalidade , Artéria Axilar/cirurgia , Cateterismo Periférico , Humanos , Isquemia/etiologia , Artéria Mesentérica Superior/diagnóstico por imagem , Radiografia , Análise de Sobrevida , Síndrome , Procedimentos Cirúrgicos Vasculares/métodos
13.
Transl Psychiatry ; 5: e524, 2015 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-25756807

RESUMO

Despite the fact that mitochondrial dysfunctions are increasingly recognized as key components in stress-related mental disorders, very little is known about the association between posttraumatic stress disorder (PTSD) and mitochondrial variants. To identify susceptibility mitochondrial genes for PTSD, we analyzed a total number of 978 mitochondrial single-nucleotide polymorphisms (mtSNPs) in a sample of 1238 individuals participating in the KORA (Cooperative Health Research in the Region of Augsburg) study. Participants were classified with 'no PTSD', 'partial PTSD' or 'full PTSD' by applying the Posttraumatic Diagnostic Scale and the Impact of Event Scale. To assess PTSD-mtSNP association while taking heteroplasmy into account, we used the raw signal intensity values measured on the microarray and applied linear regression. Significant associations were obtained between full versus no PTSD and two mtSNPs; mt8414C->T (ß=-0.954±0.06, Padjusted=0.037) located in adenosine triphosphate (ATP) synthase subunit 8 (MT-ATP8) and mt12501G->A (ß=-1.782±0.40, Padjusted=0.015) located in the NADH dehydrogenase subunits 5 (MT-ND5). Heteroplasmy for the two variants towards a larger number of the respective minor alleles increases the risk of having PTSD. NADH dehydrogenase and ATP synthase are both linked to the regulation of reactive oxygen species. Our results highlight the important role of the mitochondrial genome among the factors that contribute to the risk of PTSD. Mitochondrial genetic variants may be more important than has previously been assumed, leading to further insights regarding effects of existing medications, or even to the development of innovative treatments. As this is the first mitochondrial genome-wide association study for PTSDs, further analyses are needed to follow up on the present findings.


Assuntos
Complexo I de Transporte de Elétrons/genética , Variação Genética/genética , Mitocôndrias/genética , Proteínas Mitocondriais/genética , ATPases Mitocondriais Próton-Translocadoras/genética , Transtornos de Estresse Pós-Traumáticos/genética , Adulto , Idoso , Feminino , Estudo de Associação Genômica Ampla/métodos , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único/genética
14.
Protein Sci ; 8(9): 1867-77, 1999 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-10493588

RESUMO

The extracellular portions of the chains that comprise the human type I interferon receptor, IFNAR1 and IFNAR2, have been expressed and purified as recombinant soluble His-tagged proteins, and their interactions with each other and with human interferon-beta-1a (IFN-beta-1a) were studied by gel filtration and by cross-linking. By gel filtration, no stable binary complexes between IFN-beta-1a and IFNAR1, or between IFNAR1 and IFNAR2 were detected. However, a stable binary complex formed between IFN-beta-1a and IFNAR2. Analysis of binary complex formation using various molar excesses of IFN-beta-1a and IFNAR2 indicated that the complex had a 1:1 stoichiometry, and reducing SDS-PAGE of the binary complex treated with the cross-linking reagent dissucinimidyl glutarate (DSG) indicated that the major cross-linked species had an apparent Mr consistent with the sum of its two individual components. Gel filtration of a mixture of IFNAR1 and the IFN-beta-1a/IFNAR2 complex indicated that the three proteins formed a stable ternary complex. Analysis of ternary complex formation using various molar excesses of IFNAR1 and the IFN-beta-1a/IFNAR2 complex indicated that the ternary complex had a 1:1:1 stoichiometry, and reducing SDS-PAGE of the ternary complex treated with DSG indicated that the major cross-linked species had an apparent Mr consistent with the sum of its three individual components. We conclude that the ternary complex forms by the sequential association of IFN-beta-1a with IFNAR2, followed by the association of IFNAR1 with the preformed binary complex. The ability to produce the IFN-beta-1a/IFNAR2 and IFN-beta-1a/IFNAR1/IFNAR2 complexes make them attractive candidates for X-ray crystallography studies aimed at determining the molecular interactions between IFN-beta-1a and its receptor.


Assuntos
Interferon beta/química , Interferon beta/metabolismo , Receptores de Interferon/química , Receptores de Interferon/metabolismo , Cromatografia em Gel , Dimerização , Histidina/química , Humanos , Interferon beta-1a , Interferon beta/isolamento & purificação , Substâncias Macromoleculares , Proteínas de Membrana , Receptor de Interferon alfa e beta , Receptores de Interferon/isolamento & purificação , Solubilidade
15.
J Biotechnol ; 47(2-3): 83-8, 1996 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-11536771

RESUMO

Seven detector packages consisting of plastic nuclear track detectors, nuclear emulsions and thermoluminescence dosimeters were exposed in different locations inside BIORACK during the IML2 mission. The detectors supplement each other in their registration characteristics and cover well the different contributions of the space radiations to the dose. In this report, results are given on total dose measurements, cosmic ray flux and neutron dose. Total doses differ by up to a factor of 1.5 and heavy ion fluxes by more than a factor of 6 in the different locations. The results are compared with those of previous missions. The mission equivalent dose for the astronauts was calculated from the measurements to be 3.8 mSv.


Assuntos
Radiação Cósmica , Monitoramento de Radiação/métodos , Voo Espacial/instrumentação , Astronave/instrumentação , Dosimetria Termoluminescente , Transferência Linear de Energia , Doses de Radiação , Monitoramento de Radiação/instrumentação , Radiometria
16.
J Photochem Photobiol B ; 32(3): 189-96, 1996 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-8622182

RESUMO

During the Spacelab mission D-2, in the experiment RD-UVRAD, precalibrated biofilms consisting of dry monolayers of immobilised spores of Bacillus subtilis (strain Marburg) were exposed, for defined intervals, to extraterrestrial solar radiation filtered through an optical filtering system, to simulate different ozone column thicknesses. After the mission, the biofilms were processed and optical densities indicative of any biological activity were determined for each exposure condition by image analysis. For the different simulated ozone column thicknesses, biologically effective irradiances were experimentally determined from the biofilm data and compared with calculated data using a radiative transfer model and the known biofilm action spectrum. The data show a strong increase in biologically effective solar UV irradiance with decreasing (simulated) ozone concentrations. The full spectrum of extraterrestrial solar radiation leads to an increment of the biologically effective irradiance by nearly three orders of magnitude compared with the solar spectrum at the surface of the Earth for average total ozone columns.


Assuntos
Bacillus subtilis/efeitos da radiação , Ozônio , Voo Espacial , Luz Solar , Raios Ultravioleta , Bacillus subtilis/fisiologia , Células Imobilizadas , Relação Dose-Resposta à Radiação , Matemática , Modelos Teóricos , Esporos Bacterianos
17.
Adv Space Res ; 30(6): 1539-45, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12575719

RESUMO

During the early evolution of life on Earth, before the formation of a protective ozone layer in the atmosphere, high intensities of solar UV radiation of short wavelengths could reach the surface of the Earth. Today the full spectrum of solar UV radiation is only experienced in space, where other important space parameters influence survival and genetic stability additionally, like vacuum, cosmic radiation, temperature extremes, microgravity. To reach a better understanding of the processes leading to the origin, evolution and distribution of life we have performed space experiments with microorganisms. The ability of resistant life forms like bacterial spores to survive high doses of extraterrestrial solar UV alone or in combination with other space parameters, e.g. vacuum, was investigated. Extraterrestrial solar UV was found to have a thousand times higher biological effectiveness than UV radiation filtered by stratospheric ozone concentrations found today on Earth. The protective effects of anorganic substances like artificial or real meteorites were determined on the MIR station. In the experiment EXOBIOLOGIE of the French PERSEUS mission (1999) it was found that very thin layers of anorganic material did not protect spores against the deleterious effects of energy-rich UV radiation in space to the expected amount, but that layers of UV radiation inactivated spores serve as a UV-shield by themselves, so that a hypothetical interplanetary transfer of life by the transport of microorganisms inside rocks through the solar system cannot be excluded, but requires the shielding of a substantial mass of anorganic substances.


Assuntos
Bacillus subtilis/efeitos da radiação , Meio Ambiente Extraterreno , Meteoroides , Voo Espacial , Raios Ultravioleta , Silicatos de Alumínio , Bacillus subtilis/genética , Argila , Reparo do DNA , Mutação , Proteção Radiológica , Esporos Bacterianos/efeitos da radiação
18.
Adv Space Res ; 16(8): 105-18, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-11542695

RESUMO

Spores of different strains of Bacillus subtilis and the Escherichia coli plasmid pUC19 were exposed to selected conditions of space (space vacuum and/or defined wavebands and intensities of solar ultraviolet radiation) in the experiment ER 161 "Exobiological Unit" of the Exobiology Radiation Assembly (ERA) on board of the European Retrievable Carrier (EURECA). After the approximately 11 months lasting mission, their responses were studied in terms of survival, mutagenesis in the his (B. subtilis) or lac locus (pUC19), induction of DNA strand breaks, efficiency of DNA repair systems, and the role of external protective agents. The data were compared with those of a simultaneously running ground control experiment. The survival of spores treated with the vacuum of space, however shielded against solar radiation, is substantially increased, if they are exposed in multilayers and/or in the presence of glucose as protective, whereas all spores in "artificial meteorites", i.e. embedded in clays or simulated Martian soil, are killed. Vacuum treatment leads to an increase of mutation frequency in spores, but not in plasmid DNA. Extraterrestrial solar ultraviolet radiation is mutagenic, induces strand breaks in the DNA and reduces survival substantially; however, even at the highest fluences, i.e. 3 x 10(8) J m-2, a small but significant fraction of spores survives the insolation. Action spectroscopy confirms results of previous space experiments of a synergistic action of space vacuum and solar UV radiation with DNA being the critical target.


Assuntos
Dano ao DNA , Meio Ambiente Extraterreno , Voo Espacial , Raios Ultravioleta , Ausência de Peso , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/genética , Bacillus subtilis/efeitos da radiação , DNA Bacteriano/efeitos dos fármacos , DNA Bacteriano/genética , DNA Bacteriano/efeitos da radiação , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/efeitos da radiação , Exobiologia , Glucose/farmacologia , Mutagênese , Plasmídeos/genética , Plasmídeos/efeitos da radiação , Proteção Radiológica , Esporos Bacterianos/efeitos dos fármacos , Esporos Bacterianos/genética , Esporos Bacterianos/efeitos da radiação , Vácuo
19.
Adv Space Res ; 22(4): 495-500, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-11542777

RESUMO

Detector packages consisting of plastic nuclear track detectors, nuclear emulsions, and theromoluminescence detectors were exposed at different locations inside the space laboratory Spacelab and at the astronauts' body and in different sections of the MIR space station. Total dose, particle fluence rate and linear energy transfer (LET) spectra of heavy ions, number of nuclear disintegrations and fast neutron fluence rates were determined of each exposure. The dose equivalent received by the Payload specialists (PSs) were calculated from the measurements, they range from 190 microSv d-1 to 770 microSv d-1. Finally, a preliminary investigation of results from a particle telescope of two silicon detectors, first used in the last BIORACK mission on STS 76, is reported.


Assuntos
Radiação Cósmica , Íons Pesados , Nêutrons , Monitoramento de Radiação/instrumentação , Atividade Solar , Voo Espacial/instrumentação , Meio Ambiente Extraterreno , Transferência Linear de Energia , Doses de Radiação , Proteção Radiológica , Radiometria/instrumentação , Dosimetria Termoluminescente , Ausência de Peso
20.
Radiat Meas ; 26(6): 979-86, 1996 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11540531

RESUMO

Detector packages consisting of plastic nuclear track detectors, nuclear emulsions, and thermoluminescence detectors were exposed inside BIORACK during the Spacelab missions IML1 and IML2, in different sections of the MIR space station, and inside the Spacelab module at rack front panels or stowage lockers and in the Spacelab tunnel during D2. In addition, during D2, each Payload Specialist (PS) has worn three permanent detector packages; one at the neck; one at the waist; and one at the ankle. Total dose measurements, particle fluence rate and LET spectra, number of nuclear disintegrations and neutron dose from this exposure are given in this report. The results are compared to theoretical calculations and to previous missions results. The dose equivalent (total radiation exposure) received by the PSs were calculated from the measurements and range from 190 to 770 microSv d-1. Finally, a cursory investigation of results from a particle telescope from two silicon detectors, first used in the last BIORACK mission on STS76, is reported.


Assuntos
Radiação Cósmica , Partículas Elementares , Monitoramento de Radiação/instrumentação , Atividade Solar , Voo Espacial/instrumentação , Oceano Atlântico , Estudos de Avaliação como Assunto , Humanos , Transferência Linear de Energia , Doses de Radiação , Monitoramento de Radiação/métodos , Radiometria , América do Sul , Astronave/instrumentação , Dosimetria Termoluminescente
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