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1.
Sci Rep ; 13(1): 7610, 2023 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-37164981

RESUMO

The incidence and mortality of traumatic brain injuries (TBI) among non-residents to countries where they occur remains unknown, warranting epidemiological research. Epidemiological data are key to inform prevention and public health policies related to TBI, as well as to help promote safe travelling practice. The aim of this study was to analyse the epidemiological patterns of TBI-related deaths among residents and non-residents in 30 European countries in 2015 using standardised European level data on causes of death. A large-scale cross-sectional study analysing TBI-related deaths in 30 European countries in 2015 among residents and non-residents to the country of occurrence of the death was conducted. Data from death certificates collected on European level by Eurostat were used to calculate the numbers of TBI-related deaths and estimate crude and age-standardised mortality rates. Rates were stratified by country, sex, age-group and by resident status. External causes of the injury were determined using the provided ICD-10 codes. 40,087 TBI-related deaths were identified; overall about 3% occurred among non-residents with highest proportions in Turkey (11%), Luxembourg (9%) and Cyprus (5%). Taking into account tourism intensity in the countries, Bulgaria, Greece and Austria showed highest rates of TBI-related deaths in non-residents: 0.7,0.5 and 0.5 per million overnight stays, respectively. The pooled age-standardised TBI-related mortality in non-residents was 0.2 (95% CI 0.1-0.3), among residents 10.4 (95% CI 9.4-11.5) per 100,000. In non-residents, TBI-related deaths were shifted to younger populations (86% in < 35 years); in non-residents 78% were 15-64 years old. Falls were predominant among residents (47%), and traffic accidents among non-residents (36%). Male:female ratio was higher among non-residents (3.9), compared to residents (2.1). Extrapolating our findings, we estimate that annually 1022 TBI-related deaths would occur to non-residents in the EU-27 + UK and 1488 in Europe as a continent. We conclude, that the primary populations at risk of TBI-related deaths in European countries differ in several characteristics between residents and non-residents to the country of the occurrence of death, which warrants for different approaches in prevention and safety promotion. Our findings suggest that TBI occurring in European countries among non-residents present a problem worthy of attention from public health and travel medicine professionals and should be further studied.


Assuntos
Lesões Encefálicas Traumáticas , Masculino , Humanos , Feminino , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Estudos Transversais , Lesões Encefálicas Traumáticas/etiologia , Áustria , Grécia , Chipre
2.
Sports Biomech ; 22(8): 921-939, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32677587

RESUMO

Upper limb strikes are frequent movements in combat sports and self-defence systems, in which numerous types of strikes can be applied. Therefore, the aim of this systematic review and meta-analysis was to summarise and compare the mechanical consequences of different types of upper limb strikes among various sports disciplines. A literature search was conducted in Scopus and Web of Science, with the following search formula: (impact force) AND (strike) AND (taekwondo) OR (karate) OR (self-defence) OR (combat sport) OR (boxing). The search resulted in 28 studies describing 9 kinds of strikes, where straight punches and reverse punches have larger mean impact forces than the kung fu punch (p < 0.001) and that a palm strike had a lower strike velocity (p < 0.001) than a reverse punch, straight punch, or junzuki punch. The highest recorded mean force was found for a straight punch (3427 N). Athletes in mixed martial arts, trainers of self-defence or tactical coaches can expect that straight punches and reverse punches should be performed at high speeds (over 10 m/s) and provide similar or larger impacts than other upper limb strikes; therefore, those punches should favour a combat athlete to win a competition or succeed in self-defence.


Assuntos
Artes Marciais , Humanos , Fenômenos Biomecânicos , Atletas , Movimento , Extremidade Superior
3.
Sports (Basel) ; 10(12)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36548502

RESUMO

The evaluation of strike impact is important for optimal training, conditioning and tactical use. Therefore, the aim of this study was to evaluate ground and pound strikes, in terms of net force variability, across genders and performance levels. Eighty-one participants, professional men (n = 8, 37 ± 6 years, 195 ± 7 cm, 113 ± 27 kg), advanced men (n = 47, 26 ± 8 years, 180 ± 7 cm, 76 ± 11 kg), and advanced women (n = 26, 21 ± 1 years, 167 ± 6 cm, 61 ± 7 kg) performed three strikes from a kneeling position into a force plate on the ground. The elbow strike resulted in the highest impulse and the palm strike in the highest peak force for all three categories. These results support the recommendation that has previously been made to teach the palm strike to beginners and advanced tactical and combat athletes. The direct punch and elbow strike net force were characterized by a double peak curve, where the first peak variability explained 70.2-84% of the net force. The second peak was pronounced in professional men during elbow strikes, which explained 16% of net force variability. The strike type determines the impact net force and its characteristics, where palm strike is typical by highest peak impact tolerance and elbow strike by double force peak with high net force impulse.

4.
J Funct Morphol Kinesiol ; 7(2)2022 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-35736021

RESUMO

Performance in strike combat sports is mostly evaluated through the values of the net force, acceleration, or speed to improve efficient training procedures and/or to assess the injury. There are limited data on the upper limb striking area, which can be a useful variable for contact pressure assessment. Therefore, the aim of this study was to determine the contact area of the upper limb in three different strike technique positions. A total of 38 men and 38 women (n = 76, 27.3 ± 8.5 years of age, 73.9 ± 13.8 kg of body weight, 173.3 ± 8.4 cm of body height) performed a static simulation of punch with a fist, palm strike, and elbow strike, where three segments of the right upper limb were scanned. The analysis of 684 images showed a correlation (r = 0.634) between weight and punch technique position in men and significant differences in elbow strike (p < 0.001) and palm strike (p < 0.0001) between women and men. In both groups, the palm demonstrated the largest area and the elbow the smallest one. These data may be used to evaluate strike contact pressure in future studies in forensic biomechanics and assessment of injury in combat sports and self-defense.

5.
Artigo em Inglês | MEDLINE | ID: mdl-33114304

RESUMO

Athletes of mixed martial arts use a ground and pound strategy with the strikes in the dominant ground position. The aim of this study was to compare the average peak force (Fpeak) among three punches and to estimate the probability of achieving a skull bone fracture force of 5.1 kN for each type of strike in male and female athletes. A total of 60 males and 31 females (26 ± 8 years, 75 ± 20 kg, 177 ± 11 cm) practicing professional self-defense at the advanced and professional levels performed 15 strikes on a force plate. The analyses of 1360 trials showed significant differences among the strikes Fpeak in females (p < 0.01) and males (p < 0.01). Straight punches had lower Fpeak than palm strikes and elbow strikes in both genders, and palm strikes had higher Fpeak than elbow strikes in females. No difference was observed between palm strikes and elbow strikes in males (p = 0.09). The ground and pound strikes resulted in higher impacts than previously reported strikes in the standing position. Male athletes can deliver a Fpeak above 5.1 kN with a probability of 36% with elbow and palm strikes. Such forces can cause head injury; therefore, the use of these strikes in competition should be carefully considered.


Assuntos
Articulação do Cotovelo , Artes Marciais , Atletas , Feminino , Humanos , Masculino , Extremidade Superior/fisiologia
6.
Nature ; 569(7757): 514-518, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31092918

RESUMO

Nature uses 64 codons to encode the synthesis of proteins from the genome, and chooses 1 sense codon-out of up to 6 synonyms-to encode each amino acid. Synonymous codon choice has diverse and important roles, and many synonymous substitutions are detrimental. Here we demonstrate that the number of codons used to encode the canonical amino acids can be reduced, through the genome-wide substitution of target codons by defined synonyms. We create a variant of Escherichia coli with a four-megabase synthetic genome through a high-fidelity convergent total synthesis. Our synthetic genome implements a defined recoding and refactoring scheme-with simple corrections at just seven positions-to replace every known occurrence of two sense codons and a stop codon in the genome. Thus, we recode 18,214 codons to create an organism with a 61-codon genome; this organism uses 59 codons to encode the 20 amino acids, and enables the deletion of a previously essential transfer RNA.


Assuntos
Engenharia Celular/métodos , Escherichia coli/genética , Código Genético/genética , Genoma Bacteriano/genética , Biologia Sintética/métodos , Aminoácidos/genética , Códon de Terminação/genética , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/metabolismo , Genes Essenciais/genética , RNA de Transferência/genética
7.
Biochemistry ; 58(5): 387-390, 2019 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-30260626

RESUMO

We recently characterized a new class of pyrrolysyl-tRNA synthetase (PylRS)/PyltRNA pairs from Methanomassiliicocales that are active and orthogonal in Escherichia coli. The aminoacyl-tRNA synthetases (aaRSs) of these pairs lack the N-terminal domain that is essential for tRNA recognition and in vivo activity in the Methanosarcina mazei ( Mm) PylRS but share a homologous active site with MmPylRS; this facilitates the transplantation of mutations discovered with existing PylRS systems into the new PylRS systems to reprogram their substrate specificity for the incorporation of noncanonical amino acids (ncAAs). Several of the new PylRS/PyltRNA pairs, or their evolved variants [including Methanomethylophilus alvus ( Ma) PylRS/ MaPyltRNA(6)CUA], are mutually orthogonal to the MmPylRS/ MmPyltRNA pair, and the active sites of the Mm pair and Ma pair can be diverged to enable the incorporation of distinct ncAAs in response to distinct codons via orthogonal translation in E. coli. Here we demonstrate that MaPylRS/ MaPyltRNA(6)CUA is orthogonal to the aaRSs and tRNAs in mammalian cells and directs efficient incorporation of ncAAs into proteins. Moreover, we confirm that the MaPylRS/ MaPyltRNA(6) and MmPylRS/ MmPyltRNA pairs are mutually orthogonal in mammalian cells and demonstrates that these pairs can be used to encode distinct ncAAs into a protein in mammalian cells. Thus, the MaPylRS/ MaPyltRNA(6)CUA pair provides an additional pair that is orthogonal in both E. coli and mammalian systems and is mutually orthogonal to the most widely used system for genetic code expansion. Our results provide a foundation for expanding the scope of genetic code expansion and may also facilitate strategies for proteome-wide ncAA tagging with mutually orthogonal systems.


Assuntos
Aminoacil-tRNA Sintetases/genética , Escherichia coli/metabolismo , Euryarchaeota/genética , Lisina/análogos & derivados , RNA de Transferência/genética , Aminoacil-tRNA Sintetases/metabolismo , Escherichia coli/genética , Euryarchaeota/metabolismo , Humanos , Lisina/metabolismo , RNA de Transferência/metabolismo
8.
Vnitr Lek ; 64(7-8): 797-801, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30441985

RESUMO

Severe carbon monoxide intoxication may cause tissue injury by hypoxemia and histotoxicity. The affection of the heart muscle often leads to transient global or regional systolic dysfunction of left ventricle or both ventricles and increased occurences of malignant arrhytmias. On the contrary, stress-induced cardiomyopathy is described as temporary segmental loss of contractility, mostly in apical segments of the left ventricle with mid- and basal sparing and less common hypokinesias in mid- or basal parts, or affection of both ventricles. This case report is dedicated to a 34-years old male, who was admitted to the department of emergency medicine after suicide attempt by carbon monoxide poisoning. Echocardiography at admission showed akinesias of midsegments of left ventricle and severe hypokinesias of apical and basal segments. Despite severe cardiogenic shock, adequate therapeutic management including mechanical ventilation, normobaric oxygenotherapy and catecholamine treatment led to a complete somatic recovery after 2 weeks, and without any permanent hypoxemic brain injury. Our case might be a coincidence of toxic cardiomyopathy, caused by carbon monoxide poisoning, and takotsubo cardiomyopathy as a result of long term exposition to combined stress factors that may lead even to a suicide attempt. Both types of cardiomyopathies often occure simultaneously due to similar pathophysiologic mechanisms. Both tako-tsubo and toxic cardiomypathy have good prognosis after overcoming the acute phase. Key words: carbon monoxide - cardiogennic shock - cardiomyopathy - suicide - tako-tsubo cardiomypathy.


Assuntos
Intoxicação por Monóxido de Carbono , Tentativa de Suicídio , Cardiomiopatia de Takotsubo , Adulto , Monóxido de Carbono , Intoxicação por Monóxido de Carbono/diagnóstico , Ecocardiografia , Eletrocardiografia , Humanos , Masculino , Cardiomiopatia de Takotsubo/diagnóstico
9.
Proc Natl Acad Sci U S A ; 115(52): E12388-E12397, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30487216

RESUMO

The suprachiasmatic nucleus (SCN) is the principal circadian clock of mammals, coordinating daily rhythms of physiology and behavior. Circadian timing pivots around self-sustaining transcriptional-translational negative feedback loops (TTFLs), whereby CLOCK and BMAL1 drive the expression of the negative regulators Period and Cryptochrome (Cry). Global deletion of Cry1 and Cry2 disables the TTFL, resulting in arrhythmicity in downstream behaviors. We used this highly tractable biology to further develop genetic code expansion (GCE) as a translational switch to achieve reversible control of a biologically relevant protein, Cry1, in the SCN. This employed an orthogonal aminoacyl-tRNA synthetase/tRNACUA pair delivered to the SCN by adeno-associated virus (AAV) vectors, allowing incorporation of a noncanonical amino acid (ncAA) into AAV-encoded Cry1 protein carrying an ectopic amber stop codon. Thus, translational readthrough and Cry1 expression were conditional on the supply of ncAA via culture medium or drinking water and were restricted to neurons by synapsin-dependent expression of aminoacyl tRNA-synthetase. Activation of Cry1 translation by ncAA in neurons of arrhythmic Cry-null SCN slices immediately and dose-dependently initiated TTFL circadian rhythms, which dissipated rapidly after ncAA withdrawal. Moreover, genetic activation of the TTFL in SCN neurons rapidly and reversibly initiated circadian behavior in otherwise arrhythmic Cry-null mice, with rhythm amplitude being determined by the number of transduced SCN neurons. Thus, Cry1 does not specify the development of circadian circuitry and competence but is essential for its labile and rapidly reversible activation. This demonstrates reversible control of mammalian behavior using GCE-based translational switching, a method of potentially broad neurobiological interest.


Assuntos
Transtornos Cronobiológicos/genética , Criptocromos/genética , Criptocromos/metabolismo , Animais , Transtornos Cronobiológicos/fisiopatologia , Relógios Circadianos/genética , Relógios Circadianos/fisiologia , Ritmo Circadiano/fisiologia , Regulação da Expressão Gênica/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Circadianas Period/metabolismo , Biossíntese de Proteínas/fisiologia , Processamento de Proteína Pós-Traducional , Núcleo Supraquiasmático/metabolismo , Fatores de Transcrição/metabolismo
11.
Nat Commun ; 9(1): 3847, 2018 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-30242154

RESUMO

Epidermal growth factor receptor (EGFR) activation by growth factors (GFs) relies on dimerization and allosteric activation of its intrinsic kinase activity, resulting in trans-phosphorylation of tyrosines on its C-terminal tail. While structural and biochemical studies identified this EGF-induced allosteric activation, imaging collective EGFR activation in cells and molecular dynamics simulations pointed at additional catalytic EGFR activation mechanisms. To gain more insight into EGFR activation mechanisms in living cells, we develop a Förster resonance energy transfer (FRET)-based conformational EGFR indicator (CONEGI) using genetic code expansion that reports on conformational transitions in the EGFR activation loop. Comparing conformational transitions, self-association and auto-phosphorylation of CONEGI and its Y845F mutant reveals that Y845 phosphorylation induces a catalytically active conformation in EGFR monomers. This conformational transition depends on EGFR kinase activity and auto-phosphorylation on its C-terminal tail, generating a looped causality that leads to autocatalytic amplification of EGFR phosphorylation at low EGF dose.


Assuntos
Receptores ErbB , Peptídeos e Proteínas de Sinalização Intercelular , Conformação Proteica , Dimerização , Receptores ErbB/química , Receptores ErbB/metabolismo , Transferência Ressonante de Energia de Fluorescência , Células HEK293 , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Fosforilação
12.
Cell Chem Biol ; 25(9): 1067-1074.e5, 2018 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-29937407

RESUMO

Protein phosphorylation regulates diverse processes in eukaryotic cells. Strategies for installing site-specific phosphorylation in target proteins in eukaryotic cells, through routes that are orthogonal to enzymatic post-translational modification, would provide a powerful route for defining the consequences of particular phosphorylations. Here we show that the SepRSv1.0/tRNAv1.0CUA pair (created from the Methanococcus maripaludis phosphoseryl-transfer RNA synthetase [MmSepRS]/Methanococcus janaschii [Mj]tRNAGCACys pair) is orthogonal in mammalian cells. We create a eukaryotic elongation factor 1 alpha (EF-1α) variant, EF-1α-Sep, that enhances phosphoserine incorporation, and combine this with a mutant of eRF1, and manipulations of the cell's phosphoserine biosynthetic pathway, to enable the genetically encoded incorporation of phosphoserine and its non-hydrolyzable phosphonate analog. Using this approach we demonstrate synthetic activation of a protein kinase in mammalian cells.


Assuntos
Código Genético , Organofosfonatos/metabolismo , Fosfosserina/análogos & derivados , Fosfosserina/metabolismo , Engenharia de Proteínas/métodos , Proteínas/genética , Aminoacil-tRNA Sintetases/genética , Aminoacil-tRNA Sintetases/metabolismo , Animais , Vias Biossintéticas , Cristalografia por Raios X , Células HEK293 , Humanos , Mathanococcus/enzimologia , Mathanococcus/genética , Organofosfonatos/química , Fator 1 de Elongação de Peptídeos/genética , Fator 1 de Elongação de Peptídeos/metabolismo , Fosforilação , Fosfosserina/análise , Proteínas/química , Proteínas/metabolismo
13.
Nat Biotechnol ; 36(2): 156-159, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29251727

RESUMO

We develop an approach to tag proteomes synthesized by specific cell types in dissociated cortex, brain slices, and the brains of live mice. By viral-mediated expression of an orthogonal pyrrolysyl-tRNA synthetase-tRNAXXX pair in a cell type of interest and providing a non-canonical amino acid with a chemical handle, we selectively label neuronal or glial proteomes. The method enables the identification of proteins from spatially and genetically defined regions of the brain.


Assuntos
Aminoacil-tRNA Sintetases/genética , Encéfalo/metabolismo , Neurônios/metabolismo , Proteoma/genética , Aminoácidos , Animais , Regulação Enzimológica da Expressão Gênica/genética , Camundongos , Neuroglia/metabolismo , RNA de Transferência/genética
14.
Nat Chem Biol ; 12(10): 776-778, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-27571478

RESUMO

Site-specific incorporation of non-natural amino acids into proteins, via genetic code expansion with pyrrolysyl tRNA synthetase (PylRS) and tRNA(Pyl)CUA pairs (and their evolved derivatives) from Methanosarcina sp., forms the basis of powerful approaches to probe and control protein function in cells and invertebrate organisms. Here we demonstrate that adeno-associated viral delivery of these pairs enables efficient genetic code expansion in primary neuronal culture, organotypic brain slices and the brains of live mice.


Assuntos
Aminoácidos/química , Aminoácidos/genética , Aminoacil-tRNA Sintetases/metabolismo , Encéfalo/citologia , Encéfalo/metabolismo , Código Genético/genética , RNA de Transferência/genética , Aminoácidos/metabolismo , Animais , Dependovirus/genética , Methanosarcina/genética , Camundongos , Estrutura Molecular , RNA de Transferência/metabolismo
15.
J Am Chem Soc ; 137(14): 4602-5, 2015 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-25831022

RESUMO

Methods to site-specifically and densely label proteins in cellular ultrastructures with small, bright, and photostable fluorophores would substantially advance super-resolution imaging. Recent advances in genetic code expansion and bioorthogonal chemistry have enabled the site-specific labeling of proteins. However, the efficient incorporation of unnatural amino acids into proteins and the specific, fluorescent labeling of the intracellular ultrastructures they form for subdiffraction imaging has not been accomplished. Two challenges have limited progress in this area: (i) the low efficiency of unnatural amino acid incorporation that limits labeling density and therefore spatial resolution and (ii) the uncharacterized specificity of intracellular labeling that will define signal-to-noise, and ultimately resolution, in imaging. Here we demonstrate the efficient production of cystoskeletal proteins (ß-actin and vimentin) containing bicyclo[6.1.0]nonyne-lysine at genetically defined sites. We demonstrate their selective fluorescent labeling with respect to the proteome of living cells using tetrazine-fluorophore conjugates, creating densely labeled cytoskeletal ultrastructures. STORM imaging of these densely labeled ultrastructures reveals subdiffraction features, including nuclear actin filaments. This work enables the site-specific, live-cell, fluorescent labeling of intracellular proteins at high density for super-resolution imaging of ultrastructural features within cells.


Assuntos
Actinas/genética , Actinas/metabolismo , Código Genético/genética , Imagem Óptica , Engenharia de Proteínas , Vimentina/genética , Vimentina/metabolismo , Actinas/química , Animais , Sítios de Ligação , Células COS , Sobrevivência Celular , Chlorocebus aethiops , Células HEK293 , Humanos , Lisina , Vimentina/química
16.
PLoS One ; 7(8): e42218, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22870307

RESUMO

Kinesin-1 plays a major role in anterograde transport of intracellular cargo along microtubules. Currently, there is an ongoing debate of whether α-tubulin K40 acetylation directly enhances the velocity of kinesin-1 and its affinity to the microtubule track. We compared motor motility on microtubules reconstituted from acetylated and deacetylated tubulin. For both, single- and multi-motor in vitro motility assays, we demonstrate that tubulin acetylation alone does not affect kinesin-1 velocity and run length.


Assuntos
Cinesinas/química , Microtúbulos/química , Tubulina (Proteína)/química , Acetilação , Animais , Cinesinas/metabolismo , Camundongos , Microtúbulos/metabolismo , Tubulina (Proteína)/metabolismo
17.
Blood Press ; 16(2): 122-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17612911

RESUMO

BACKGROUND/AIMS: Aortic stenosis (AS) and hypertension are associated with cardiac hypertrophy and aortic dilatation. The effect of their coincidence on the ascending aortic dimensions has not yet been evaluated, and therefore was the aim of our study. METHODS: We performed cross-sectional analysis of history, clinical, angiographic and echocardiographic data of consecutive patients evaluated before surgery for non-rheumatic AS. RESULTS: The study sample included 225 patients (age 68+/-9 years, 60% males), with mean transaortic gradient of 55+/-17 mmHg. Hypertension was present in 153 (68%) patients. The hypertensives had more severe dyspnea (NYHA class 2.2+/-0.9 vs 1.9+/-0.9, p = 0.05) and higher prevalence of coronary artery disease (57% vs 33%, p = 0.001), but did not differ from the normotensives in the ascending aortic dimensions, the left ventricular mass, ejection fraction and remodeling patterns. Wider ascending aortic dimensions were independently associated with bicuspid aortic valve (p<0.001), and with maximal gradient in those with tricuspid aortic valve. Vasodilators were used in 84 (54%) hypertensives. CONCLUSION: We found hypertension in 68% of patients with severe AS. Bicuspid aortic valve and stenosis severity were independent predictors of ascending aortic dimensions, but not the history of hypertension and blood pressure.


Assuntos
Aorta/patologia , Estenose da Valva Aórtica/patologia , Ecocardiografia , Hipertensão/patologia , Idoso , Anti-Hipertensivos/uso terapêutico , Aorta/diagnóstico por imagem , Estenose da Valva Aórtica/diagnóstico por imagem , Estudos Transversais , Feminino , Humanos , Hipertensão/diagnóstico por imagem , Hipertensão/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Valva Mitral/diagnóstico por imagem , Estudos Retrospectivos
18.
Circ J ; 71(1): 84-8, 2007 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17186983

RESUMO

BACKGROUND: Dilatation of the ascending aorta in aortic stenosis may be partly explained by intrinsic wall structure changes, but the relative contribution of altered hemodynamics is unclear. The aim of this study was to assess the association between ascending aortic dimensions and valve stenosis severity. METHODS AND RESULTS: An analysis of echocardiographic examinations was conducted in 296 patients with aortic stenosis (179 males, mean age 71 years), 57 with bicuspid and 239 with tricuspid aortic valve, mean transaortic gradient 43+/-20 mmHg, and not more than moderate aortic regurgitation. Aortic dimensions at the level of annulus, sinuses of Valsalva, sinotubular junction and proximal ascending aorta were measured. Only height (p<0.001), degree of aortic regurgitation (p<0.01) and presence of bicuspid aortic valve (p<0.001) were independent predictors of ascending aortic dimensions. CONCLUSIONS: An independent association between aortic pressure gradients and proximal ascending aortic dimensions was not observed in patients with bicuspid or tricuspid aortic valve stenosis. Therefore, the poststenotic dilatation of the ascending aorta is not explained by aortic stenosis severity itself. Possible nonhemodynamic causes deserve detailed study at the time of diagnosis.


Assuntos
Aorta/patologia , Aorta/fisiopatologia , Estenose da Valva Aórtica/patologia , Índice de Gravidade de Doença , Idoso , Insuficiência da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/fisiopatologia , Pressão Sanguínea , Dilatação Patológica/patologia , Dilatação Patológica/fisiopatologia , Ecocardiografia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valva Mitral/patologia , Valva Mitral/fisiopatologia , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Estenose da Valva Tricúspide/patologia , Estenose da Valva Tricúspide/fisiopatologia
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