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1.
HNO ; 69(11): 907-912, 2021 Nov.
Artigo em Alemão | MEDLINE | ID: mdl-33439274

RESUMO

BACKGROUND: Ultrasound diagnostics are widely used and are standard for radiologists, otolaryngologists, and oral and maxillofacial surgeons in the diagnostic work-up of various pathologies. There is agreement that digital documentation is urgently needed at present to improve and standardize the quality of sonographic documentation. There are more and more publications on the implementation of standardized documentation of findings in imaging diagnostics, including head and neck sonography. OBJECTIVE: The present work aims to determine the quality of routine head and neck sonography findings on a random basis, according to the criteria of the Bavarian Association of Statutory Health Insurance Physicians (KVB) at a selection of German university otolaryngology departments (ENT). MATERIALS AND METHODS: A total of 70 randomly selected anonymized written findings including image documentation from seven ENT departments were retrospectively analyzed by an experienced KVB examiner concerning fulfilment of KVB criteria. The data were evaluated descriptively. RESULTS: Of the 70 reports, 69 were eligible for evaluation. The average documentation completeness was 80.6%. A total of 9 findings were correctly documented in full (13%). The documentation completeness of the individual departments was sorted in ascending order from 68.1% to 93%. With 88.5% vs. 75%, the hospitals with a structured report showed a higher level of completeness. In 75% of the cases the hospitals with structured reports also had digital solutions for reporting and image archiving. CONCLUSION: In general, there is potential for optimization regarding the completeness and quality of routinely prepared head and neck sonography findings at the selected university ENT departments. The implementation of structured reporting masks and the conversion of analogue documentation into digital solutions as well as digital networking with the hospital information systems, picture archiving and communication systems should be promoted. Supervision by senior doctors is required to ensure the quality of findings of inexperienced colleagues and to help to achieve standards in reporting.


Assuntos
Cabeça , Pescoço , Documentação , Cabeça/diagnóstico por imagem , Hospitais Universitários , Humanos , Pescoço/diagnóstico por imagem , Estudos Retrospectivos , Ultrassonografia
2.
Exp Clin Endocrinol Diabetes ; 120(7): 405-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22576260

RESUMO

The aim of the study was to investigate plasma ADH levels and plasma/urine osmolality in patients suffering from bilateral Menière's disease since a disturbance in the water household after thirst challenge is a suspected pathogenic factor in the development of this disease. In this study the plasma ADH levels and plasma/urine osmolality of bilateral Menière's disease patients under thirst challenge were investigated to show whether the water balance is affected. 9 patients with bilateral Menière's disease and 9 healthy controls skipped water intake for 12 h. Plasma ADH, plasma/urine osmolality, and electrolytes were measured after this thirst period as well as 8 h later after food and fluid intake. During food and fluid intake the patients demonstrated a slightly higher plasma ADH level and plasma osmolality than controls, whereas at the end of the thirst period patients and the controls showed no significant change. Instead the urine osmolality differed significantly (p<0.001): showing a high urine osmolality in controls and an almost stable urine osmolality in patients after thirst challenge. This indicates that the water balance in patients is likely different from that of controls. These observations point to ADH and its target aquaporine 2 as keyplayers in the pathophysiological events leading to the development of Menière's disease.


Assuntos
Doença de Meniere/sangue , Vasopressinas/sangue , Água/administração & dosagem , Adulto , Idoso , Aquaporina 2/fisiologia , Sangue , Feminino , Humanos , Masculino , Doença de Meniere/fisiopatologia , Doença de Meniere/urina , Pessoa de Meia-Idade , Concentração Osmolar , Potássio/sangue , Potássio/urina , Sódio/sangue , Sódio/urina , Sede , Urina
3.
Eur Arch Otorhinolaryngol ; 269(2): 475-80, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21739095

RESUMO

The literature about bony defects in the semicircular canal system is highly inconsistent. Therefore, we analyzed a series of 700 high-resolution multislice CT examinations of the temporal bone for semicircular canal dehiscencies. An unselected group of ENT patients with different clinical symptoms and variable age was chosen. We found semicircular canal dehiscence in 9.6% of temporal bones, superior semicircular canal was affected mostly (8%), less common posterior semicircular canal (1.2%); only in 3 cases (0.4%), lateral semicircular canal showed dehiscence. In 60% of SSC dehiscence, we registered bilateral manifestation. The so-called "third mobile window" in semicircular canal dehiscence causes a great variety of clinical symptoms like vertigo, nystagmus, oscillopsies, hearing loss, tinnitus and autophonia. Comparison with anatomic studies shows that CT examination implies the risk of considerable overestimation; this fact emphasizes the important role of clinical and neurophysiological testing.


Assuntos
Doenças do Labirinto/diagnóstico por imagem , Doença de Meniere/diagnóstico por imagem , Tomografia Computadorizada Multidetectores , Canais Semicirculares/diagnóstico por imagem , Osso Temporal/diagnóstico por imagem , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Colesteatoma da Orelha Média/complicações , Colesteatoma da Orelha Média/diagnóstico por imagem , Colesteatoma da Orelha Média/epidemiologia , Estudos Transversais , Humanos , Lactente , Doenças do Labirinto/epidemiologia , Labirintite/complicações , Labirintite/diagnóstico por imagem , Labirintite/epidemiologia , Doença de Meniere/epidemiologia , Pessoa de Meia-Idade , Fatores de Risco , Canais Semicirculares/lesões , Osso Temporal/lesões , Adulto Jovem
4.
HNO ; 58(2): 110-2, 114-6, 2010 Feb.
Artigo em Alemão | MEDLINE | ID: mdl-20111915

RESUMO

According to German law granting of driving licenses depends on the proof of an adequate driving capability. The corresponding guidelines are at present in the process of being revised. At the moment bilateral deafness and high-grade hearing loss (> or = 60% in pure tone audiometry) are not exclusion criteria for driving licenses grades A, B and C, while driving licenses grade D and licenses for public transport are generally excluded. In the forthcoming revised edition of the guidelines it has been suggested that the latter group will also not be excluded. The regulations concerning dizziness are wide-sweeping at the moment as no driving license will be granted if dizziness is present but will be more specific in the next issue. In particular a division will be made between single axle and two axle vehicles. An expert assessment about driving suitability can only be made by a certified specialist with qualifications in traffic medicine.


Assuntos
Acidentes de Trânsito/legislação & jurisprudência , Acidentes de Trânsito/prevenção & controle , Exame para Habilitação de Motoristas/legislação & jurisprudência , Surdez/diagnóstico , Tontura/diagnóstico , Prova Pericial/legislação & jurisprudência , Licenciamento/legislação & jurisprudência , Otolaringologia/legislação & jurisprudência , Audiometria de Tons Puros , Surdez/classificação , Avaliação da Deficiência , Tontura/classificação , Definição da Elegibilidade/legislação & jurisprudência , Alemanha , Humanos , Veículos Automotores/classificação , Veículos Automotores/legislação & jurisprudência
5.
HNO ; 57(5): 487-502, 2009 May.
Artigo em Alemão | MEDLINE | ID: mdl-19387595

RESUMO

The vestibular system has the ability to repair deficits due to functional lesions, which is known as vestibular compensation. For successful function the performance of different receptors is less important than the bilateral balance of neuronal activity between the vestibular nuclei complexes. In this review based on data from animal experiments and clinical observations, the mechanisms of vestibular compensation, its time course and its clinical significance are described. Most of the clinical features can be explained by neuronal operations known from animal experiments. It must be emphasized that vestibular compensation is not a static phenomenon but a fluctuating process which can be influenced by therapeutic procedures. Vestibular compensation for static phenomena can be almost completely carried out, but for dynamic features only incompletely. These factors should be taken in account for diagnosis, therapy and assessment of vestibular disturbances.


Assuntos
Recuperação de Função Fisiológica/fisiologia , Doenças Vestibulares/fisiopatologia , Vestíbulo do Labirinto/fisiopatologia , Animais , Humanos
6.
Ann Otolaryngol Chir Cervicofac ; 124(4): 173-83, 2007 Sep.
Artigo em Francês | MEDLINE | ID: mdl-17678612

RESUMO

OBJECTIVES: To establish during a consensus meeting the fundamental basis, the validity criteria, the main indications and results of the skull vibration induced nystagmus test (SVINT) which explores the vestibule high frequencies. MATERIAL AND METHODS: The SVINT is applied on the mastoid process (right and left sides) at 100 Hz during 10 seconds on a sitting upright subject. Total unilateral peripheral lesions (tUVL: operated vestibular shwannomas, vestibular neurectomies) and partial unilateral peripheral lesions (pUVL: preoperative neuromas, Meniere's disease, vestibular neuritis, chemical labyrinthectomies) were studied. Thirty-six patients had brainstem lesions and 173 normal subjects were used as controls. RESULTS: The SVINT is considered positive when the application of the vibrator produces a reproducible sustained nystagmus always beating in the same direction following several trials in various stimulation topographies (on the right and left mastoid). The skull vibratory nystagmus (SVN) begins and ends with the stimulation; the direction of the nystagmus has no secondary reversal. The slow phase velocity (SPV) is>2 degrees /second. In tUVL the SVINT always reveals a lesional nystagmus beating toward the safe side at all frequencies. The mean SVN SPV is 10.8 degrees /s+/-7.5 SD (N=45). The mastoid site was more efficient than the cervical or vertex sites. Mastoïd stimulation efficiency is not correlated with the side of stimulation. The SVN SPV is correlated with the total caloric efficiency on the healthy ear. In pUVL the SVINT is positive in 71 to 76% of cases; the mean SVN. SPV (6.7 degrees /s+/-4.7 SD)(N=30) is significantly lower than in tUVL (P=0.0004). SVINT is positive in 6 to 10% of the normal population, 31% of brain stem lesions and negative in total bilateral vestibular peripheral lesions. CONCLUSIONS: SVINT is an effective, rapid and non invasive test used to detect vestibular asymmetry between 20 to 150 Hz stimulation. This test used in important cohorts of patients during the ten last years has demonstrated no observable adverse effect. SVINT complements other tests which evaluate lower frequencies (caloric test: 0,003 Hz) and the medium frequencies (Head-Shaking-Test (HST): 2 Hz; the head impulse test (HIT): 6 Hz). SVINT is useful in the diagnosis of labyrinthine hydrops or detection of acoustic neuromas. It is useful when the caloric test can not be practised because of middle ear problems. SVINT has its limits: in pUVL, the nystagmus direction is not always specific of the pathologic side and can change with the stimulus frequency. This test does not precisely point out the level of the lesion on the vestibular pathway.


Assuntos
Nistagmo Patológico/epidemiologia , Nistagmo Patológico/etiologia , Otolaringologia/métodos , Vibração/efeitos adversos , Adulto , Idoso , Testes Calóricos , Edema/diagnóstico , Edema/epidemiologia , Reações Falso-Positivas , Feminino , Humanos , Masculino , Processo Mastoide , Doença de Meniere/diagnóstico , Doença de Meniere/epidemiologia , Pessoa de Meia-Idade , Neuroma Acústico/diagnóstico , Neuroma Acústico/epidemiologia , Prevalência , Sensibilidade e Especificidade , Índice de Gravidade de Doença , Crânio/fisiologia , Doenças Vestibulares/diagnóstico , Doenças Vestibulares/epidemiologia , Neuronite Vestibular/diagnóstico , Neuronite Vestibular/epidemiologia
7.
HNO ; 55(4): 258-63, 2007 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-17031676

RESUMO

BACKGROUND: The concept for the medical treatment of vertigo has changed over the last 30 years due to recognition of the dependence of the vertiginous sensation on vestibular compensation and the dependence of vestibular compensation on the state of vigilance. METHODS: In this systematic review, experimental studies of the influence of the special ginkgo extract EGb 761 on vestibular compensation in animals and randomized, double-blind clinical studies of EGb 761 in vestibular and non-vestibular vertigo are described and critically evaluated. RESULTS: The beneficial effect of EGb 761 on vestibular compensation has been demonstrated in preclinical and clinical studies. CONCLUSION: Evidence of the efficacy of EGb 761 for the treatment of vertiginous syndromes is presented in the available studies.


Assuntos
Avaliação Pré-Clínica de Medicamentos/tendências , Extratos Vegetais/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto/tendências , Vertigem/tratamento farmacológico , Vertigem/fisiopatologia , Vestíbulo do Labirinto/efeitos dos fármacos , Vestíbulo do Labirinto/fisiopatologia , Animais , Relação Dose-Resposta a Droga , Método Duplo-Cego , Avaliação Pré-Clínica de Medicamentos/estatística & dados numéricos , Ginkgo biloba , Humanos , Avaliação de Resultados em Cuidados de Saúde , Efeito Placebo , Ensaios Clínicos Controlados Aleatórios como Assunto/estatística & dados numéricos , Resultado do Tratamento , Vertigem/diagnóstico
8.
HNO ; 54(5): 415-26; quiz 427, 2006 May.
Artigo em Alemão | MEDLINE | ID: mdl-16614841

RESUMO

The recording of vestibular evoked myogenic potentials is a relatively new neuro-otologic method which gives specific information about the function of the sacculus and the inferior vestibular nerve on each side separately. The main indications for this method are vestibular schwannoma and fistula of the labyrinth, involvement of the sacculus or the inferior vestibular nerve in Menière's disease and vestibular neuritis, vertigo of unknown etiology, and forensic questions.


Assuntos
Eletromiografia , Potencial Evocado Motor/fisiologia , Fístula/diagnóstico , Doenças do Labirinto/diagnóstico , Doença de Meniere/diagnóstico , Neuroma Acústico/diagnóstico , Sáculo e Utrículo/fisiopatologia , Vertigem/etiologia , Nervo Vestibular/fisiopatologia , Neuronite Vestibular/diagnóstico , Estimulação Acústica , Diagnóstico Diferencial , Fístula/fisiopatologia , Humanos , Doenças do Labirinto/fisiopatologia , Doença de Meniere/fisiopatologia , Músculos do Pescoço/inervação , Neuroma Acústico/fisiopatologia , Valor Preditivo dos Testes , Processamento de Sinais Assistido por Computador , Neuronite Vestibular/fisiopatologia
10.
Ophthalmologe ; 99(5): 363-6, 2002 May.
Artigo em Alemão | MEDLINE | ID: mdl-12043291

RESUMO

BACKGROUND: A deviation of the subjective visual vertical (svv) is often found in patients with unilateral peripheral vestibular lesions and in most cases the deviation is transitory and easy to compensate. The purpose of the study was to find out if there is a correlation between deviation of the svv and objective cyclodeviation of the retina. PATIENTS AND METHODS: A total of 20 patients (10 females and 10 males aged between 16 and 78 years) with acute vestibular disease were enrolled. Only patients with a binocular deviation of the svv of more than 2 degrees and/or a difference between the monocular deviation of more than 1.5 degrees were included. The svv was examined monocular in a darkened room and after pupil dilatation, fundus photography was performed on each eye. The angle between papilla and macula was measured manually. RESULTS: We found a good qualitative correlation between svv (mean 7.9 degrees) and objective cyclodeviation (mean 10.6 degrees). CONCLUSION: In contrast to the binocular measurement of the svv, we found good correlation between the monocular svv and the objective cyclorotation measured with fundus photography. It is not yet clear which part of the vestibular system is responsible for cyclodeviation. Because of our results we recommend monocular measurement of the svv in clinical examinations.


Assuntos
Orientação/fisiologia , Reconhecimento Visual de Modelos/fisiologia , Retina/fisiopatologia , Doenças Vestibulares/diagnóstico , Visão Monocular/fisiologia , Adolescente , Adulto , Idoso , Feminino , Angiofluoresceinografia , Lateralidade Funcional/fisiologia , Humanos , Masculino , Pessoa de Meia-Idade , Membrana dos Otólitos/fisiopatologia , Propriocepção/fisiologia , Doenças Vestibulares/fisiopatologia
11.
J Biol Chem ; 276(44): 40896-902, 2001 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-11533042

RESUMO

The histidine kinase/response regulator system EnvZ/OmpR of Escherichia coli regulates transcription of the genes ompF and ompC, encoding two porins of the outer membrane. Although the total amount of OmpF and OmpC remains constant, the relative levels of the two proteins fluctuate in a reciprocal manner depending on medium osmolality. The membrane-anchored sensor EnvZ somehow monitors changes in environmental osmolality. To characterize the nature of the stimulus perceived by EnvZ, this protein was overproduced, purified, and reconstituted into proteoliposomes. Autokinase activity of purified and reconstituted EnvZ was stimulated by an increase of the K(+) concentration. Rb(+), Na(+), and NH4(+) also stimulated the activity but to a smaller extent, whereas an osmotic upshift imposed by various sugars or increasing concentrations of glycine betaine, proline, or Tris/MES were without influence. Neither the transfer of the phosphoryl group from EnvZ approximately P to OmpR nor the EnvZ-mediated OmpR approximately P dephosphorylation were affected by one of the tested solutes. Experiments with the reconstructed signal transduction cascade including DNA fragments demonstrated a substantial increase of the amount of phosphorylated OmpR in the presence of K(+) and to a lower extent in the presence of Na(+), Rb(+), and NH4(+). Various K(+) salts were tested indicating that the determined effects were K(+)-specific and not dependent on the anion. In a further in vitro test system, which utilizes right-side-out membrane vesicles, the K(+)-specific activation of EnvZ autokinase from the luminal side was confirmed. These results clearly indicate a regulation of EnvZ autokinase activity by monovalent ions, specifically K(+). Whether K(+) accumulation, which is one of the first responses of E. coli after an osmotic upshift, is related to the stimulation of the EnvZ autokinase activity in vivo is discussed.


Assuntos
Proteínas da Membrana Bacteriana Externa/metabolismo , Proteínas de Escherichia coli/metabolismo , Complexos Multienzimáticos/metabolismo , Potássio/metabolismo , Proteínas Quinases/metabolismo , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/isolamento & purificação , Sequência de Bases , Primers do DNA , Ativação Enzimática , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/isolamento & purificação , Complexos Multienzimáticos/genética , Complexos Multienzimáticos/isolamento & purificação , Mutagênese Sítio-Dirigida , Fosforilação , Transdução de Sinais
12.
Forensic Sci Int ; 113(1-3): 109-12, 2000 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-10978610

RESUMO

The 4977 bp deletion of mitochondrial DNA (mtDNA) accumulates in postmitotic tissues with advancing age. The purpose of our study was to detect and quantify these deletion even in blood cells with a high turnover activity. Whole venous blood, isolated human platelets and peripheral blood mononuclear cells (PBMCs) were collected from 10 unrelated donors aged 20-71 years and total DNA was extracted. PCR was performed for total and mutated mtDNA using two different primer pairs and two fluorogenic probes labeled with the fluorescent dyes FAM and VIC. Specific PCR products were generated, detected and quantified in a real-time PCR. The amplification products of total and deleted mtDNA could be detected in each sample and did not exhibit any differences in the amount of the deleted mtDNA in whole blood, human platelets or PBMCs. Our data did not show any accumulation of the 4977 bp deletion with increasing age as it was observed for several other tissues.


Assuntos
Envelhecimento/genética , Sequência de Bases/genética , Análise Química do Sangue/instrumentação , Análise Química do Sangue/métodos , Plaquetas/química , DNA Mitocondrial/análise , Leucócitos Mononucleares/química , Reação em Cadeia da Polimerase/métodos , Análise de Sequência de DNA/instrumentação , Análise de Sequência de DNA/métodos , Deleção de Sequência/genética , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Análise de Regressão , Sensibilidade e Especificidade
13.
Am J Physiol Lung Cell Mol Physiol ; 278(3): L618-24, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10710535

RESUMO

Hypertrophy and hyperplasia lead to excess accumulation of smooth muscle in the airways of human asthmatic subjects. However, little is known about mechanisms that might counterbalance these processes, thereby limiting the quantity of smooth muscle in airways. Ligation of Fas on the surface of vascular smooth muscle cells and nonmuscle airway cells can lead to apoptotic cell death. We therefore tested the hypotheses that 1) human airway smooth muscle (HASM) expresses Fas, 2) Fas cross-linking induces apoptosis in these cells, and 3) tumor necrosis factor (TNF)-alpha potentiates Fas-mediated airway myocyte killing. Immunohistochemistry using CH-11 anti-Fas monoclonal IgM antibody revealed Fas expression in normal human bronchial smooth muscle in vivo. Flow cytometry using DX2 anti-Fas monoclonal IgG antibody revealed that passage 4 cultured HASM cells express surface Fas. Surface Fas decreased partially during prolonged serum deprivation of cultured HASM cells and was upregulated by TNF-alpha stimulation. Fas cross-linking with CH-11 antibody induced apoptosis in cultured HASM cells, and this effect was reduced by long-term serum deprivation and synergistically potentiated by concomitant TNF-alpha exposure. TNF-alpha did not induce substantial apoptosis in the absence of Fas cross-linking. These data represent the first demonstration that Fas is expressed on HASM and suggest a mechanism by which Fas-mediated apoptosis could act to oppose excess smooth muscle accumulation during airway remodeling in asthma.


Assuntos
Anticorpos Monoclonais/farmacologia , Apoptose/fisiologia , Brônquios/fisiologia , Músculo Liso Vascular/fisiologia , Receptor fas/imunologia , Receptor fas/fisiologia , Apoptose/efeitos dos fármacos , Brônquios/citologia , Brônquios/metabolismo , Membrana Celular/metabolismo , Células Cultivadas , Sinergismo Farmacológico , Humanos , Imuno-Histoquímica , Músculo Liso Vascular/citologia , Músculo Liso Vascular/metabolismo , Fator de Necrose Tumoral alfa/farmacologia , Receptor fas/metabolismo
15.
Am J Physiol ; 277(4): L802-10, 1999 10.
Artigo em Inglês | MEDLINE | ID: mdl-10516222

RESUMO

We examined the effect of eosinophil ligation to cultured human umbilical vein endothelial cells (HUVECs) in augmenting the stimulated secretion of leukotriene (LT) C(4) and eosinophil peroxidase (EPO). The effects of adhesion were compared before and after specific blockade with monoclonal antibodies directed against eosinophil surface integrins or endothelial counterligands. Adhesion to HUVECs augmented EPO release caused by formyl-methionyl-leucyl-phenylalanine plus cytochalasin B from 403 +/- 15.3 (BSA control) to 778 +/- 225 ng/10(6) cells for eosinophils exposed to interleukin-1alpha-treated HUVECs (P < 0.05) and also caused a twofold increase in stimulated LTC(4) secretion (P < 0.05). To determine whether augmented secretion resulted directly from adhesive ligation, studies were also performed with paraformaldehyde-treated HUVECs; stimulated secretion of LTC(4) from eosinophils was comparable to that for living HUVECs. Our study is the first demonstration that adhesion to HUVECs through ligation to alpha(4)- or beta(2)-integrin on the eosinophil surface causes augmentation of stimulated secretion of both EPO and LTC(4) and that blockade of adhesion molecules on either eosinophils or HUVECs prevents the priming effect on eosinophil secretion.


Assuntos
Degranulação Celular/fisiologia , Endotélio Vascular/fisiologia , Eosinófilos/fisiologia , Integrinas/fisiologia , Leucotrieno C4/metabolismo , Anticorpos Monoclonais/farmacologia , Adesão Celular/fisiologia , Sobrevivência Celular , Endotélio Vascular/citologia , Endotélio Vascular/imunologia , Endotélio Vascular/metabolismo , Peroxidase de Eosinófilo , Eosinófilos/imunologia , Humanos , Ligantes , Peroxidases/metabolismo , Fatores de Tempo , Veias Umbilicais/citologia , Veias Umbilicais/imunologia , Veias Umbilicais/metabolismo , Veias Umbilicais/fisiologia , Regulação para Cima
16.
Curr Eye Res ; 18(6): 430-9, 1999 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10435830

RESUMO

PURPOSE: To evaluate the inhibitory effect of human fetal retinal pigment epithelium (HFRPE) on the activation of human T-cells. METHODS: Pure cultures of HFRPE cells were incubated with purified human T-cells in three different activation assays: 1) allogenic peripheral blood mononuclear cells; 2) OKT3 coated beads in the presence of accessory cells; and 3) stimulation with phorbol ester and phytohemagglutinin. RESULTS: HFRPE cells suppressed the activation of T-cells in all three assays. The mechanism of HFRPE mediated T-cell suppression was apoptosis. The role of Fas ligand(FasL)/Fas-mediated T-cell suppression was excluded, since FasL protein or mRNA could not be detected on HFRPE cells with flow cytometry and by reverse transcriptase polymerase chain reaction, respectively. Additionally, the inhibitory effect of HFRPE cells could not be blocked by anti-Fas ligand or antagonistic anti-Fas antibodies. Moreover, HFRPE cells suppressed the proliferation of anti-CD3 mAb mediated T-cell proliferation of murine splenocytes isolated from lpr mice. The inhibitory effect of HFRPE cells was not PGE2 mediated, since indomethacin could not restore the T-cell activation. Although the HFRPE mediated T-cell apoptosis was cell-cell contact independent, it was not induced by secretion of TNF-alpha, TGF-beta, or IL-10. The ratio between HFRPE and T-cells had a major impact on the HFRPE's inhibitory effect. CONCLUSIONS: HFRPE cells suppressed the activation of human T-cells by induction of T-cell apoptosis through a process that involves the secretion of soluble factors. The HFRPE mediated T-cell suppression was dependent on the ratio between HFRPE and T-cells. This undefined pathway of T-cell apoptosis may play a role in the maintenance of immune privilege in the subretinal space and may reduce the severity of the immune response after HFRPE transplantation.


Assuntos
Apoptose/fisiologia , Dinoprostona/fisiologia , Feto/fisiologia , Glicoproteínas de Membrana/fisiologia , Epitélio Pigmentado Ocular/embriologia , Linfócitos T/fisiologia , Animais , Comunicação Celular/fisiologia , Meios de Contraste , Citocinas/fisiologia , Proteína Ligante Fas , Feto/citologia , Fluoresceína , Humanos , Ativação Linfocitária/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Microscopia de Fluorescência
17.
Histochem J ; 31(3): 145-51, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10421413

RESUMO

Glycosylated structures on the cell surface have a role in cell adhesion, migration, and proliferation. Repair of the airway epithelium after injury requires each of these processes, but the normal cell surface glycosylation of non-mucin producing airway epithelial cells is unknown. We examined cell surface glycosylation in human airway epithelial cells in tissue sections and in human airway epithelial cell lines in culture. Thirty-eight lectin probes were used to determine specific carbohydrate residues by lectin-histochemistry. Galactose or galactosamine-specific lectins labeled basal epithelial cells, lectins specific for several different carbohydrate structures bound columnar epithelial cells, and fucose-specific lectins labeled all airway epithelial cells. The epithelial cell lines 1HAEo- and 16HBE14o- bound lectins that were specific to basal epithelial cells. Flow cytometry of these cell lines with selected lectins demonstrated that lectin binding was to cell surface carbohydrates, and revealed possible hidden tissue antigens on dispersed cultured cells. We demonstrate specific lectin-binding patterns on the surface of normal human airway epithelial cells. The expression of specific carbohydrate residues may be useful to type epithelial cells and as a tool to examine cell events involved in epithelial repair.


Assuntos
Células Epiteliais/metabolismo , Células Epiteliais/ultraestrutura , Lectinas/metabolismo , Pulmão/citologia , Glicoproteínas de Membrana/biossíntese , Glicoproteínas de Membrana/metabolismo , Linhagem Celular Transformada/química , Linhagem Celular Transformada/ultraestrutura , Citometria de Fluxo , Glicoconjugados/biossíntese , Histocitoquímica , Humanos , Pulmão/metabolismo
18.
Am J Respir Cell Mol Biol ; 20(4): 787-96, 1999 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10101012

RESUMO

Repair of the airway epithelium after injury requires that processes such as adhesion and cell migration occur in a defined order. Both of these processes depend on interactions between extracellular matrix (ECM) proteins and appropriate integrins. To study these interactions, we examined monolayer wound repair in a cultured human airway epithelial cell line, 16HBE14o-. Wounds created in confluent monolayers grown on either collagen-IV, laminin-1, or laminin-2 matrix closed quickly in response to 15 ng/ml epidermal growth factor (EGF). Concurrent treatment of cells grown on each matrix protein with EGF and a monoclonal antibody (mAb) to beta1-integrin inhibited wound closure. Treatment with a mAb to alpha2-, alpha3-, and alpha6-integrin blocked wound repair in monolayers grown on collagen-IV but did not do so in monolayers grown either on laminin-1 or laminin-2. Inhibition was not due to cell detachment or apoptosis. These data demonstrate that integrins expressed by airway epithelial cells mediate wound closure on different constitutive ECM proteins. These data suggest that beta1-integrin subunit function is required to permit migration and spreading of epithelial cells, and that alpha-integrin subunits alone do not mediate migration of epithelial cells grown on either laminin-1 or laminin-2. These differences may become important if the matrix protein composition of airway basement membrane changes in disease states such as asthma.


Assuntos
Apoptose , Células Epiteliais/fisiologia , Integrina beta1/fisiologia , Receptores de Antígeno muito Tardio/fisiologia , Cicatrização , Anticorpos Monoclonais/farmacologia , Brônquios , Divisão Celular , Linhagem Celular Transformada , Colágeno/fisiologia , Fator de Crescimento Epidérmico/farmacologia , Células Epiteliais/citologia , Células Epiteliais/patologia , Proteínas da Matriz Extracelular/fisiologia , Citometria de Fluxo , Humanos , Integrina beta1/imunologia , Laminina/fisiologia , Receptores de Antígeno muito Tardio/biossíntese , Vírus 40 dos Símios
19.
Artigo em Inglês | MEDLINE | ID: mdl-10095196

RESUMO

Vibrations of 60 Hz and 100 Hz were applied on the mastoid of healthy subjects, patients with unilateral peripheral vestibular lesions, with central lesions of different localizations, and patients with benign paroxysmal positioning vertigo (BPPV). In patients with unilateral peripheral deficit a horizontal nystagmus with a small torsional component beating generally to the not affected side could be observed. This nystagmus did not show adaptation during 40 s. The occurrence was more frequent using 60-Hz stimulations. This vibration-induced nystagmus did never occur in healthy subjects, seldom in patients with central vertigo, and only exceptionally in patients with BPPV. It is concluded that the finding of a vibration-induced nystagmus reflects a side difference of peripheral vestibular excitability.


Assuntos
Nistagmo Patológico/fisiopatologia , Doenças Vestibulares/fisiopatologia , Vibração , Humanos , Processo Mastoide , Vertigem/diagnóstico , Vertigem/fisiopatologia , Doenças Vestibulares/diagnóstico
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