Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 73
Filtrar
1.
Chem Biol Interact ; 390: 110872, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38244963

RESUMO

In patients with prostate carcinoma as well as in some other cancer types, the reduction of testosterone levels is desired because the hormone stimulates cancer cell growth. One molecular target for this goal is the inhibition of 17ß-hydroxysteroid dehydrogenase type 3 (17ßHSD3), which produces testosterone from its direct precursor androstenedione. Recent research in this field is trying to harness photopharmacological properties of certain compounds so that the inhibitory effect could be turned on and off by irradiation. Seven new light-switchable diazocines were investigated with regard to their inhibition of 17ßHSD3. For this purpose, transfected HEK-293 cells and isolated microsomes were treated with the substrate and the potential inhibitors with and without irradiation for an incubation period of 3 or 5 h. The amount of generated testosterone was measured by UHPLC and compared between samples and control as well as between irradiated and non-irradiated samples. There was no significant difference between samples with and without irradiation. However, four of the seven diazocines led to a significantly lower testosterone production both in cell and in microsome assays. In some of the irradiated samples, a partial destruction of the diazocines was observed, indicated by an additional UHPLC peak. However, the influence on the inhibition is negligible, because the majority of the substance remained intact. In conclusion, new inhibitors of 17ßHSD3 have been found, but so far without the feature of a light switch, since the configurational alteration of the diazocines by irradiation did not lead to a change in bioactivity. Further modification might help to find a light-switching molecule that inhibits only in one configuration.


Assuntos
Neoplasias da Próstata , Testosterona , Masculino , Humanos , Testosterona/metabolismo , Células HEK293 , Neoplasias da Próstata/metabolismo , 17-Hidroxiesteroide Desidrogenases/metabolismo , Androstenodiona/metabolismo , Androstenodiona/uso terapêutico
2.
Dis Aquat Organ ; 130(2): 95-108, 2018 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-30198485

RESUMO

The fountain darter Etheostoma fonticola (FOD) is a federally endangered fish listed under the US Endangered Species Act. Here, we identified and characterized a novel aquareovirus isolated from wild fountain darters inhabiting the San Marcos River. This virus was propagated in Chinook salmon embryo (CHSE)-214, rainbow trout gonad-2 and fathead minnow cells at 15°C. The epithelioma papulosum cyprini cell line was refractory at all temperatures evaluated. High throughput sequencing technologies facilitated the complete genome sequencing of this virus utilizing ribosomal RNA-depleted RNA extracted from infected CHSE-214 cells. Conventional PCR primer sets were developed for the detection and confirmation of this virus to assist diagnostic screening methods. Phylogenetic analysis suggests this virus belongs to the Aquareovirus A genus. This research provides requisite initial data critical to support hatchery and refugia biosecurity measures for this endangered species.


Assuntos
Percas , Filogenia , Reoviridae , Animais , Espécies em Perigo de Extinção , Percas/virologia , Reoviridae/genética , Reoviridae/isolamento & purificação , Rios
3.
Phys Med Biol ; 62(19): 7617-7640, 2017 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-28796645

RESUMO

Modern radiotherapy of female breast cancers often employs high dose rate brachytherapy, where a radioactive source is moved inside catheters, implanted in the female breast, according to a prescribed treatment plan. Source localization relative to the patient's anatomy is determined with solenoid sensors whose spatial positions are measured with an electromagnetic tracking system. Precise sensor dwell position determination is of utmost importance to assure irradiation of the cancerous tissue according to the treatment plan. We present a hybrid data analysis system which combines multi-dimensional scaling with particle filters to precisely determine sensor dwell positions in the catheters during subsequent radiation treatment sessions. Both techniques are complemented with empirical mode decomposition for the removal of superimposed breathing artifacts. We show that the hybrid model robustly and reliably determines the spatial positions of all catheters used during the treatment and precisely determines any deviations of actual sensor dwell positions from the treatment plan. The hybrid system only relies on sensor positions measured with an EMT system and relates them to the spatial positions of the implanted catheters as initially determined with a computed x-ray tomography.


Assuntos
Braquiterapia/instrumentação , Neoplasias da Mama/radioterapia , Fenômenos Eletromagnéticos , Imagens de Fantasmas , Planejamento da Radioterapia Assistida por Computador/métodos , Idoso , Artefatos , Neoplasias da Mama/diagnóstico por imagem , Catéteres , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Dosagem Radioterapêutica , Tomografia Computadorizada por Raios X/métodos
4.
Technol Cancer Res Treat ; 16(4): 470-481, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-27422012

RESUMO

OBJECTIVE: The difference in the resonance frequency of water and methylene moieties of lipids quantifies in magnetic resonance spectroscopy the absolute temperature using a predefined calibration curve. The purpose of this study was the investigation of peak evaluation methods and the magnetic resonance spectroscopy sequence (point-resolved spectroscopy) parameter optimization that enables thermometry during deep hyperthermia treatments. MATERIALS AND METHODS: Different Lorentz peak-fitting methods and a peak finding method using singular value decomposition of a Hankel matrix were compared. Phantom measurements on organic substances (mayonnaise and pork) were performed inside the hyperthermia 1.5-T magnetic resonance imaging system for the parameter optimization study. Parameter settings such as voxel size, echo time, and flip angle were varied and investigated. RESULTS: Usually all peak analyzing methods were applicable. Lorentz peak-fitting method in MATLAB proved to be the most stable regardless of the number of fitted peaks, yet the slowest method. The examinations yielded an optimal parameter combination of 8 cm3 voxel volume, 55 millisecond echo time, and a 90° excitation pulse flip angle. CONCLUSION: The Lorentz peak-fitting method in MATLAB was the most reliable peak analyzing method. Measurements in homogeneous and heterogeneous phantoms resulted in optimized parameters for the magnetic resonance spectroscopy sequence for thermometry.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Animais , Calibragem , Interpretação Estatística de Dados , Hipertermia Induzida , Imagens de Fantasmas , Sus scrofa , Termometria
5.
Handb Clin Neurol ; 137: 235-40, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27638075

RESUMO

The leading symptoms of bilateral vestibulopathy (BVP) are postural imbalance and unsteadiness of gait that worsens in darkness and on uneven ground. There are typically no symptoms while sitting or lying under static conditions. A minority of patients also have movement-induced oscillopsia, in particular while walking. The diagnosis of BVP is based on a bilaterally reduced or absent function of the vestibulo-ocular reflex (VOR). This deficit is diagnosed for the high-frequency range of the angular VOR by a bilaterally pathologic bedside head impulse test (HIT) and for the low-frequency range by a bilaterally reduced or absent caloric response. If the results of the bedside HIT are unclear, angular VOR function should be quantified by a video-oculography system (vHIT). An additional test supporting the diagnosis is dynamic visual acuity. Cervical and ocular vestibular-evoked myogenic potentials (c/oVEMP) may also be reduced or absent, indicating impaired otolith function. There are different subtypes of BVP depending on the affected anatomic structure and frequency range of the VOR deficit: impaired canal function in the low- and/or high-frequency VOR range only and/or otolith function only; the latter is very rare. The etiology of BVP remains unclear in more than 50% of patients: in these cases neurodegeneration is assumed. Frequent known causes are ototoxicity mainly due to gentamicin, bilateral Menière's disease, autoimmune diseases, meningitis and bilateral vestibular schwannoma, as well as an association with cerebellar degeneration (cerebellar ataxia, neuropathy, vestibular areflexia syndrome=CANVAS). In general, in the long term there is no improvement of vestibular function. There are four treatment options: first, detailed patient counseling to explain the cause, etiology, and consequences, as well as the course of the disease; second, daily vestibular exercises and balance training; third, if possible, treatment of the underlying cause, as in bilateral Menière's disease, meningitis, or autoimmune diseases; fourth, if possible, prevention, i.e., being very restrictive with the use of ototoxic substances, such as aminoglycosides. In the future vestibular implants may also be an option.


Assuntos
Vestibulopatia Bilateral/fisiopatologia , Reflexo Vestíbulo-Ocular/fisiologia , Vestibulopatia Bilateral/diagnóstico , Vestibulopatia Bilateral/etiologia , Movimentos Oculares , Humanos , Membrana dos Otólitos/patologia , Membrana dos Otólitos/fisiopatologia
6.
Nervenarzt ; 86(10): 1277-90, 2015 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-26440631

RESUMO

The key to diagnosing vertigo and balance disorders is systematic analysis of case history with clinical examination of the vestibular, oculomotor, and cerebral systems in particular. Important criteria for differentiating between the various vertigo syndromes are 1) the time course of symptoms, 2) the type of symptoms, 3) modulating factors, and 4) associated symptoms. For clinical examination of the vestibular system, six important tests are available: assessment of spontaneous nystagmus, head impulse test, dynamic visual acuity, subjective visual verticality, positioning manoeuvre, and the Romberg test/gait analysis with eyes open and closed. On the basis of five clinical signs (vertical divergence, central fixation nystagmus, gaze-evoked nystagmus, saccades, normal head impulse test), the clinical examination is able to differentiate between acute central and peripheral vestibular syndromes with a sensitivity and specificity of over 90%. The most relevant laboratory examinations are caloric irrigation and the video head-impulse test for canal function and the vestibular evoked myogenic potentials for otolith function. Finally, treatment is based upon four therapeutic principles: physiotherapy, pharmacotherapy, psychotherapy, and in rare cases, surgery.


Assuntos
Anamnese/métodos , Vertigem/diagnóstico , Vertigem/terapia , Doenças Vestibulares/diagnóstico , Doenças Vestibulares/terapia , Testes de Função Vestibular/métodos , Tomada de Decisão Clínica/métodos , Diagnóstico Diferencial , Técnicas de Diagnóstico Neurológico , Humanos , Doenças Vestibulares/complicações
7.
Clin Genet ; 86(2): 155-60, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23927549

RESUMO

Alport syndrome is an inherited progressive nephropathy arising from mutations in the type IV collagen genes, COL4A3, COL4A4, and COL4A5. Symptoms also include sensorineural hearing loss and ocular lesions. We determined the molecular basis of Alport syndrome in a non-consanguineous Ashkenazi Jewish family with multiple affected females using linkage analysis and next generation sequencing. We identified a homozygous COL4A3 mutation, c.40_63del, in affected individuals with mutant alleles inherited from each parent on partially conserved haplotypes. Large-scale population screening of 2017 unrelated Ashkenazi Jewish samples revealed a carrier frequency of 1 in 183 indicating that COL4A3 c.40_63del is a founder mutation which may be a common cause of Alport syndrome in this population. Additionally, we determined that heterozygous mutation carriers in this family do not meet criteria for a diagnosis of Thin Basement Membrane Nephropathy and concluded that carriers of c.40_63del are not likely to develop benign familial hematuria.


Assuntos
Autoantígenos/genética , Colágeno Tipo IV/genética , Etnicidade/genética , Efeito Fundador , Genes Recessivos , Mutação/genética , Nefrite Hereditária/genética , Sequência de Bases , Pré-Escolar , Feminino , Ligação Genética , Haplótipos/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Programas de Rastreamento , Dados de Sequência Molecular , Linhagem
8.
Arch Environ Contam Toxicol ; 65(4): 790-7, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24121718

RESUMO

Toxicity tests evaluated chronic and sublethal effects of fog oil (FO) on a freshwater endangered fish. FO is released during military training as an obscurant smoke that can drift into aquatic habitats. Fountain darters, Etheostoma fonticola, of four distinct life stages were exposed under laboratory conditions to three forms of FO. FO was vaporized into smoke and allowed to settle onto water, violently agitated with water, and dosed onto water followed by photo-oxidization by ultraviolet irradiation. Single smoke exposures of spawning adult fish did not affect egg production, egg viability, or adult fish survival in 21-day tests. Multiple daily smoke exposures induced mortality after 5 days for larvae fish. Larvae and juvenile fish were more sensitive than eggs in 96-h lethal concentration (LC50) tests with FO­water mixtures and photo-oxidized FO. Water-soluble FO components photo-modified by ultraviolet radiation were the most toxic, thus indicating the value of examining weathering and aging of chemicals for the best determination of environmental impact.


Assuntos
Óleos/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Espécies em Perigo de Extinção , Militares/educação , Percas , Medição de Risco , Tempo (Meteorologia)
9.
Oncogene ; 29(14): 2024-35, 2010 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-20140014

RESUMO

S100 proteins modulate p53 activity by interacting with its tetramerization (p53TET, residues 325-355) and transactivation (residues 1-57) domains. In this study, we characterized biophysically the binding of S100A1, S100A2, S100A4, S100A6 and S100B to homologous domains of p63 and p73 in vitro by fluorescence anisotropy, analytical ultracentrifugation and analytical gel filtration. We found that S100A1, S100A2, S100A4, S100A6 and S100B proteins bound different p63 and p73 tetramerization domain variants and naturally occurring isoforms with varying affinities in a calcium-dependent manner. Additional interactions were observed with peptides derived from the p63 and p73 N-terminal transactivation domains. Importantly, S100 proteins bound p63 and p73 with different affinities in their different oligomeric states, similarly to the differential modes of binding to p53. On the basis of our data, we hypothesize that S100 proteins regulate the oligomerization state of all three p53 family members and their isoforms, with a potential physiological relevance in developmental and disease-related processes. The regulation of the p53 family by S100 is complicated and depends on the target preference of each individual S100 protein, the concentration of the proteins and calcium, as well as the splicing variation of p63 or p73. Our results outlining the complexity of the interaction should be considered when studying the functional effects of S100 proteins in their biological context.


Assuntos
Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Proteínas Nucleares/química , Proteínas Nucleares/metabolismo , Proteínas S100/metabolismo , Homologia de Sequência de Aminoácidos , Proteína Supressora de Tumor p53/química , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/metabolismo , Animais , Cálcio/metabolismo , Cromatografia em Gel , Polarização de Fluorescência , Humanos , Ligação Proteica , Multimerização Proteica , Estrutura Quaternária de Proteína , Estrutura Terciária de Proteína , Ativação Transcricional , Proteína Tumoral p73 , Ultracentrifugação
10.
J Neurol ; 254(12): 1689-97, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17990061

RESUMO

Nicotine has wellknown, unpleasant side effects, e.g., transient dizziness, nausea, and nicotine-induced nystagmus (NIN). To investigate factors influencing these effects, we addressed three questions: (1) Is the intensity of dizziness, nausea, NIN, and unsteadiness dependent on nicotine dosage? (2) Does the intensity of perceptual, ocular motor, vegetative effects, and postural imbalance correlate? (3) Do visual or vestibular motion stimuli produce and/or aggravate distressing dizziness and nausea? Sixty healthy non-smokers or occasional smokers participated; 40 were tested once before and six times after application of a nicotine nasal spray in doses of 1 mg or 2 mg with or without motion stimulation; 20 received a placebo nasal spray. Plasma nicotine concentrations were significantly related to nicotine dosage. Dizziness, nausea, NIN, and unsteadiness also depended on the nicotine dosage (p < 0.01).Nicotine blood concentration was a better predictor for the temporal dependence of nystagmus than nicotine dosage. Dizziness correlated highly with nausea (R = 0.63, p < 0.001). The degree of nicotine-induced nausea significantly correlated with postural imbalance. The time course of postural sway differed according to nicotine dosage and gender: for women, there was no clear relationship between sway magnitude and nicotine dosage, while men showed increased sway with higher dosage. Motion stimulation increased nicotine-induced dizziness and nausea, but did not significantly influence NIN or postural imbalance. Our data support the view that all measured adverse effects reflect dose-dependent nicotine-induced vestibular dysfunction. Additional motion stimulation aggravates dizziness and nausea, i.e., nicotine increases sensitivity to motion sickness.


Assuntos
Nicotina/administração & dosagem , Agonistas Nicotínicos/administração & dosagem , Transtornos da Percepção , Transtornos de Sensação , Doenças Vestibulares , Administração Intranasal , Adulto , Análise de Variância , Tontura/induzido quimicamente , Tontura/fisiopatologia , Relação Dose-Resposta a Droga , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Movimento (Física) , Náusea/induzido quimicamente , Náusea/fisiopatologia , Nicotina/sangue , Agonistas Nicotínicos/sangue , Nistagmo Optocinético/efeitos dos fármacos , Transtornos da Percepção/induzido quimicamente , Transtornos da Percepção/fisiopatologia , Postura/fisiologia , Distribuição Aleatória , Descanso , Transtornos de Sensação/induzido quimicamente , Transtornos de Sensação/fisiopatologia , Doenças Vestibulares/induzido quimicamente , Doenças Vestibulares/fisiopatologia
11.
Nervenarzt ; 78(10): 1160-74, 2007 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-17457558

RESUMO

In German neurorehabilitation, the ambiguous term "early rehabilitation" reflects the multidisciplinary, rehabilitative treatment of severely impaired patients in continuing need of acute and intensive care (including weaning from the respirator in selected cases). The actual definition of this treatment is discussed, which hitherto corresponded to Phase B according to recommendations of the German Federal Study Group for Rehabilitation (BAR) and now has started to be integrated into the diagnosis-related group system. The tasks and aims of early rehabilitation are to support and enhance neuroplastic remission of nervous system functional loss and continued medical care, improve vigilance, establish cooperativity, and evaluate the rehabilitation potential including compensatory and adaptive strategies organizing posthospital care, reducing the need of nursing support, and improving quality of life. Some special aspects of early rehabilitative care are presented here in more detail. To fulfill these tasks, a multidisciplinary team is required including various therapists qualified for neurorehabilition, physicians (including a neurologist), nurses, and social workers. Outcome data were assessed using our 5-year prospective early rehabilitation registry. Fifty-five percent of patients improved to reach the next step of neurorehabilitation (Phase C), with significant gain in function even in the subgroup of aged and most severely disabled patients. The trend to transfer patients very early in the postacute Phase to early rehabilitation facilities, with open medical problems and increased risk of complications, makes close cooperation and interaction with acute medical centers necessary.


Assuntos
Doenças do Sistema Nervoso Central/reabilitação , Procedimentos Neurocirúrgicos/reabilitação , Modalidades de Fisioterapia , Reabilitação Vocacional , Dano Encefálico Crônico/reabilitação , Cuidadores/educação , Terapia Combinada , Transtornos de Deglutição/reabilitação , Grupos Diagnósticos Relacionados/legislação & jurisprudência , Alemanha , Humanos , Cobertura do Seguro/legislação & jurisprudência , Programas Nacionais de Saúde/legislação & jurisprudência , Terapia Ocupacional , Equipe de Assistência ao Paciente , Resultado do Tratamento
12.
Nervenarzt ; 77 Suppl 1: S17-29; quiz S30, 2006 Sep.
Artigo em Alemão | MEDLINE | ID: mdl-16897046

RESUMO

Dissection of a cervicocerebral artery (CAD) is the second leading cause of stroke at younger ages. The pathogenesis of spontaneous CAD is not fully clarified. Defective connective tissue components may cause an arteriopathy predisposing to CAD in combination with certain trigger and risk factors. The clinical spectrum includes local pain in the neck, headaches, Horner's syndrome, isolated cranial nerve deficits, and hemispheric or brainstem infarction. Noninvasively, CAD is confirmed by Duplex sonography, MRI, and MRA. There is no controlled study for best treatment or management. Rational initial empiric treatment in acute CAD to prevent secondary embolism is partial thromboplastin time-guided anticoagulation by intravenous heparin followed by anticoagulation with warfarin. Carotid surgery for treating CAD is not recommended. The duration of anticoagulation is best guided by Doppler sonography follow-up and should extend until normalization of blood flow or at least 6 months after the vessel was occluded. Caution should be recommended for exercises that involve excessive head movements. The recurrence rate for CAD is low at <1%/year except for patients with known hereditary connective tissue disorders or in cases with familial dissections.


Assuntos
Anticoagulantes/administração & dosagem , Anticoagulantes/uso terapêutico , Dissecção Aórtica/diagnóstico , Dissecção Aórtica/tratamento farmacológico , Aneurisma Intracraniano/diagnóstico , Aneurisma Intracraniano/tratamento farmacológico , Acidente Vascular Cerebral/prevenção & controle , Dissecção Aórtica/complicações , Humanos , Aneurisma Intracraniano/complicações , Guias de Prática Clínica como Assunto , Padrões de Prática Médica , Prognóstico , Acidente Vascular Cerebral/etiologia
13.
Ultrasound Med Biol ; 30(9): 1119-31, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15550316

RESUMO

Ten formalin-fixed atherosclerotic carotid plaques removed by endarterectomy were molded into rectangular agar blocks containing fiducial markers on the top surface. Plaque and fiducial markers were imaged with 3-D multiangle ultrasound (US) spatial compounding as well as planar X ray. Subsequently, the blocks were decalcified, sliced, photographed and analyzed histologically. This gave a total of 123 slices. The plaque regions of the photographs were outlined and the outline adjusted to partly compensate for occasional displacement during slicing. Inside this outline, the material constitutions were found by incorporating the histologic information. From this set, slices with 1. too much tissue displacement due to cutting or 2. lack of identification of calcification as found by x ray, were removed. This resulted in 53 reference maps. The material types identified covered soft tissues, fibrous tissue, calcified tissue and unidentified tissues. The 53 reference maps can be used for direct automated quantitative comparison with US images.


Assuntos
Arteriosclerose/diagnóstico por imagem , Estenose das Carótidas/diagnóstico por imagem , Arteriosclerose/patologia , Calcinose/diagnóstico por imagem , Calcinose/patologia , Artérias Carótidas/diagnóstico por imagem , Artérias Carótidas/patologia , Estenose das Carótidas/patologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Fotografação/métodos , Valores de Referência , Reprodutibilidade dos Testes , Ultrassonografia
14.
Neurology ; 63(7): 1209-16, 2004 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-15477540

RESUMO

BACKGROUND: In a recent study, the authors found that blinks in healthy volunteers always triggered ocular torsion quick phases during dynamic roll movements of the head. On the basis of this observation, they hypothesized that blinks in patients with a vestibular tone imbalance would also trigger torsional quick phases. METHODS: Using video-oculography with a fixation target, the authors recorded the ocular torsion position of the left eye of 37 participants while they made voluntary blinks once every 6 to 10 seconds. The participants were recruited from four groups: two age groups of healthy volunteers with a mean +/- SD age of 32 +/- 4 (n = 9) and 65 +/- 11 y (n = 9); patients with a unilateral vestibular disorder in an acute state (n = 12, 53 +/- 17 y); and those in a persisting state in which spontaneous nystagmus had already faded (n = 9, 65 +/- 13 y). RESULTS: In the control groups of healthy volunteers, blinks triggered no or only small quick phases on the order of 0.1 deg. In both patient groups blinks always triggered quick phases with significantly higher amplitudes of 1.85 +/- 1.02 deg and were followed by exponentially decaying slow-phases with time constants on the order of 1 to 2 seconds. Patients in the persisting state clearly differed from patients in the acute state in that their torsional spontaneous nystagmus had already vanished due to vestibular compensation. But surprisingly, these two groups did not show a large difference in terms of the effect of blinks on ocular torsion. The authors always observed torsional quick phases with the upper pole of the eye beating away from the side of the lesion. CONCLUSIONS: Blinks are able to trigger torsional quick phases in patients with both acute and persisting vestibular disorders. The side of the impairment can be determined from the direction in which the eye is rotated after a blink. Thus, ocular torsion recordings during blinks can be used as a simple clinical test for a vestibular tone imbalance, particularly during a persisting failure in which spontaneous nystagmus has resolved and can therefore no longer be used for diagnosis.


Assuntos
Piscadela/fisiologia , Movimentos Oculares/fisiologia , Doenças Vestibulares/diagnóstico , Doenças Vestibulares/fisiopatologia , Adulto , Isquemia Encefálica/fisiopatologia , Feminino , Humanos , Masculino , Neuroma Acústico/fisiopatologia , Sensibilidade e Especificidade , Anormalidade Torcional , Neuronite Vestibular/fisiopatologia , Núcleos Vestibulares/irrigação sanguínea
15.
Neurology ; 62(7): 1190-2, 2004 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-15079023

RESUMO

The authors searched for the presence of alpha-1-antitrypsin (AAT) deficiency alleles PiZ and PiS in 74 patients with spontaneous cervical artery dissections (sCADs) and in 74 healthy control subjects. In both groups, the authors found four carriers of deficiency alleles. The connective tissue morphology of one additional patient with sCAD with PiZM genotype and her relatives was studied in skin biopsies. The PiZ allele did not segregate with morphologic alterations of the dermal connective tissue in the family. Therefore, AAT deficiency alleles may not play a role in the etiology of sCAD.


Assuntos
Dissecação da Artéria Carótida Interna/genética , Frequência do Gene , Dissecação da Artéria Vertebral/genética , Deficiência de alfa 1-Antitripsina/genética , Adulto , Biópsia , Dissecação da Artéria Carótida Interna/epidemiologia , Causalidade , Cromossomos/genética , Tecido Conjuntivo/patologia , Derme/patologia , Feminino , Triagem de Portadores Genéticos , Alemanha/epidemiologia , Humanos , Masculino , Linhagem , Polimorfismo Conformacional de Fita Simples , Valores de Referência , Suíça/epidemiologia , Dissecação da Artéria Vertebral/epidemiologia , Deficiência de alfa 1-Antitripsina/epidemiologia
16.
Cerebrovasc Dis ; 16(1): 83-7, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12766367

RESUMO

BACKGROUND: Paradoxical embolism via persistent foramen ovale (PFO) is suspected to be a frequent cause of stroke in younger patients. We investigated whether the prevalence of the risk factors for venous thrombosis factor V Leiden (FVL) and prothrombin G20210A mutation (PT G20210A) is increased in this group of patients. METHODS: We examined FVL and PT G20210A mutation in 220 patients (group 1) with cerebral ischemia associated with a PFO and without other etiology, in 196 patients with cerebral ischemia of an etiology other than PFO (group 2), and in 362 healthy subjects (group 3) from the same region in Germany. RESULTS: Heterozygosity for the PT G20210A mutation was more common in group 1 (5.0%) than in group 3 (1.4%; sex- and age-adjusted odds ratio 3.66; 95% CI 1.25-10.75; p = 0.01). By contrast, the mutation was not more common in group 2 (2.6%; odds ratio 1.50; 95% CI 0.42-5.41; p = 0.5). Prevalences of FVL were not different between groups. CONCLUSIONS: We identified PT G20210A but not FVL - the strongest genetic risk factor for deep venous thrombosis - to be significantly associated with stroke attributed to PFO. These findings rise doubts about the concept of paradoxical brain embolism as the dominating mechanism in stroke associated with PFO.


Assuntos
Isquemia Encefálica/genética , Fator V/genética , Comunicação Interatrial/genética , Mutação/genética , Protrombina/genética , Adulto , Idoso , Isquemia Encefálica/fisiopatologia , Diabetes Mellitus/fisiopatologia , Feminino , Comunicação Interatrial/fisiopatologia , Heterozigoto , Humanos , Hipertensão/complicações , Hipertensão/fisiopatologia , Trombose Intracraniana/genética , Trombose Intracraniana/fisiopatologia , Ataque Isquêmico Transitório/genética , Ataque Isquêmico Transitório/fisiopatologia , Masculino , Pessoa de Meia-Idade , Razão de Chances , Fatores de Risco , Fumar/fisiopatologia , Acidente Vascular Cerebral/genética , Acidente Vascular Cerebral/fisiopatologia , Ultrassonografia Doppler Transcraniana
17.
Eur J Clin Invest ; 31(11): 999-1006, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11737243

RESUMO

BACKGROUND: Enhanced stimulus-induced release of pro-inflammatory cytokines by leucocytes may contribute to the pathogenesis of ischaemic stroke. DESIGN: We investigated the lipopolysaccharide-induced release of interleukin-1beta (IL-1beta), IL-6, IL-8, and tumour necrosis factor-alpha (TNF-alpha) in whole blood from 20 patients with a history of ischaemic stroke under the age of 50, 20 patients with a history of cervical artery dissection (CAD) and 21 age- and sex-matched healthy control subjects. RESULTS: Release of IL-8 was higher (P = 0.006) and release of TNF-alpha and IL-6 tended to be higher (P < 0.1) in young stroke patients than in control subjects. No increased release existed in CAD patients. Vascular risk factors or history of infection before stroke did not modify IL-8 production. A common T(250) --> A polymorphism in the IL-8 gene promotor was newly identified but did not correlate with the variability of IL-8 release. The C(260) --> T polymorphism in the gene of the monocytic LPS-receptor CD14--a risk factor for myocardial infarction--was not associated with increased cytokine release. CONCLUSIONS: We conclude that high inducible release of IL-8--and possibly of TNF-alpha and IL-6--may contribute to the odds of ischaemic stroke in young adults.


Assuntos
Interleucina-1/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Leucócitos/imunologia , Acidente Vascular Cerebral/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Envelhecimento , Dissecção Aórtica/imunologia , Feminino , Humanos , Interleucina-1/genética , Interleucina-8/genética , Leucócitos/metabolismo , Lipopolissacarídeos/farmacologia , Masculino , Polimorfismo Genético , Fatores de Risco
18.
Stroke ; 32(11): 2559-66, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11692017

RESUMO

BACKGROUND AND PURPOSE: Data on risk factors for etiologic subtypes of ischemic stroke are still scant. The aim of this study was to characterize stroke subtypes regarding risk factor profile, outcome, and current treatment strategies. METHODS: We analyzed data from 5017 patients with acute ischemic stroke (42.4% women, aged 65.9+/-14.1 years) who were enrolled in a large multicenter hospital-based stroke data bank. Standardized data assessment and stroke subtype classification were used by all centers. RESULTS: Sex and age distribution, major risk factors and comorbidities, recurrent stroke, treatment strategies, and outcome were all unevenly distributed among stroke subtypes (P<0.001, respectively). Cardioembolism, the most frequent etiology of stroke (25.6%), was particularly common in the elderly (those aged >70 years) and associated with an adverse outcome, a low rate of early stroke recurrence, and frequent use of thrombolytic therapy and intravenous anticoagulation. Large-artery atherosclerosis (20.9%), the most common cause of stroke in middle-aged patients (those aged 45 to 70 years), showed the highest male preponderance, highest rate of early stroke recurrence, and highest prevalence of previous transient ischemic attack, current smoking, and daily alcohol consumption among all subtypes. The highest prevalence of hypertension, diabetes mellitus, hypercholesterolemia, and obesity was found in small-vessel disease (20.5%), which, in turn, was associated with the lowest stroke severity and mortality. CONCLUSIONS: Our results foster the concept of ischemic stroke as a polyetiologic disease with marked differences between subtypes regarding risk factors and outcome. Therefore, studies involving risk factors of ischemic stroke should differentiate between etiologic stroke subtypes.


Assuntos
Isquemia Encefálica/classificação , Acidente Vascular Cerebral/classificação , Adulto , Idoso , Isquemia Encefálica/diagnóstico , Isquemia Encefálica/etiologia , Isquemia Encefálica/terapia , Bases de Dados Factuais , Feminino , Alemanha , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/etiologia , Acidente Vascular Cerebral/terapia
19.
Neurology ; 57(1): 24-30, 2001 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-11445623

RESUMO

BACKGROUND: The etiology of spontaneous cervical artery dissection (CAD) is largely unknown. An underlying connective tissue disorder has often been postulated. OBJECTIVE: To further assess the association of CAD with ultrastructural abnormalities of the dermal connective tissue. METHODS: In a multicenter study, skin biopsies of 65 patients with proven nontraumatic CAD and 10 control subjects were evaluated. The ultrastructural morphology of the dermal connective tissue components was assessed by transmission electron microscopy. RESULTS: Only three patients (5%) had clinical manifestations of skin, joint, or skeletal abnormalities. Ultrastructural aberrations were seen in 36 of 65 patients (55%), consisting of the regular occurrence of composite fibrils within collagen bundles that in some cases resembled the aberrations found in Ehlers-Danlos syndrome type II or III and elastic fiber abnormalities with minicalcifications and fragmentation. A grading scale according to the severity of the findings is introduced. Intraindividual variability over time was excluded by a second biopsy of the skin in eight patients with pronounced aberrations. Recurrent CAD correlated with connective tissue aberrations. In addition, similar connective tissue abnormalities were detected in four first-degree relatives with familial CAD. CONCLUSION: CAD is associated with ultrastructural connective tissue abnormalities, mostly without other clinical manifestations of a connective tissue disease. A structural defect in the extracellular matrix of the arterial wall leading to a genetic predisposition is suggested. The dermal connective tissue abnormalities detected can serve as a phenotypic marker for further genetic studies in patients with CAD and large families to possibly identify the underlying basic molecular defect(s).


Assuntos
Dissecção Aórtica/etiologia , Doenças das Artérias Carótidas/etiologia , Doenças do Tecido Conjuntivo/complicações , Pescoço/irrigação sanguínea , Adulto , Artéria Carótida Interna , Doenças do Tecido Conjuntivo/patologia , Tecido Elástico/patologia , Feminino , Humanos , Masculino , Microscopia Eletrônica , Pessoa de Meia-Idade , Valores de Referência , Pele/patologia
20.
J Neurol Sci ; 186(1-2): 1-5, 2001 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-11412864

RESUMO

Chronic infection may increase the risk for ischemic stroke. Presently, it is insufficiently established whether Helicobacter pylori infection represents a risk factor for ischemic stroke. We analyzed IgG antibodies against H. pylori in 109 patients with acute cerebral ischemia and 82 age- and sex-matched control patients with non-vascular and non-inflammatory neurological diseases. Antibody titers were significantly higher in patients than in control subjects (p=0.007). H. pylori seropositivity tended to be more common in patients (odds ratio (OR) 1.55, 95% confidence interval (ci) 0.87-2.76), but this trend was further attenuated in multivariate analysis (OR 1.42; 95% 0.75-2.67) with hypertension, diabetes mellitus, current or previous smoking, previous cerebral ischemia and low socioeconomic status. H. pylori seropositivity increased the odds for cerebral ischemia of atherothrombotic origin in univariate (OR 3.63; 95% ci 1.37-9.65) and multivariate analysis (OR 3.53; 95% ci 1.09-11.4). H. pylori seropositivity may be an independent risk factor for stroke of atherothrombotic origin.


Assuntos
Isquemia Encefálica/epidemiologia , Isquemia Encefálica/microbiologia , Infecções por Helicobacter/epidemiologia , Helicobacter pylori , Trombose Intracraniana/epidemiologia , Trombose Intracraniana/microbiologia , Idoso , Anticorpos Antibacterianos/sangue , Feminino , Infecções por Helicobacter/complicações , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Estudos Soroepidemiológicos , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/microbiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA