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1.
Int J Oral Maxillofac Surg ; 49(10): 1303-1310, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32173246

RESUMO

Incorrect registration of the condylar position in orthognathic surgery is supposed to cause postoperative relapse, condylar resorption and temporomandibular disorders. The aim of this prospective study was to evaluate the influence of general anaesthesia on centric relation (CR). Therefore, CR registered preoperatively in the awake patient and CR registered intraoperatively under general anaesthesia were recorded in 30 patients (14 men, 16 women) undergoing orthognathic surgery (skeletal class I: n=3, II: n=13, III: n=14; symmetric: n=20; asymmetric: n=10). CR records were digitized and, through superimposition on the preoperative cone beam computed tomography of the patient's skull, the superior, anterior and posterior joint space and the volumetric congruence of 120 condyles were analysed. The linear measurements of joint spaces did not demonstrate any clinically relevant discrepancy between the CR measured in the awake and anaesthetized patient. In contrast, volumetric analysis revealed statistically significant differences between both states, with an intraoperative condylar sag predominantly in the posterior-inferior direction. The patient's skeletal class or symmetry had no significant influence on the intraoperative condylar displacement. Thus, the risk of fixing the condyle in an unphysiological position supports the idea of using intraoperative condylar positioning devices to achieve predictable and stable outcomes.


Assuntos
Cirurgia Ortognática , Anestesia Geral , Feminino , Humanos , Masculino , Côndilo Mandibular/diagnóstico por imagem , Osteotomia de Le Fort , Estudos Prospectivos
2.
Int J Oral Maxillofac Surg ; 49(2): 157-165, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31345665

RESUMO

Tumour progression in head and neck squamous cell carcinoma (HNSCC) is influenced by the surrounding stroma and inflammatory cytokines such as tumour necrosis factor alpha (TNF-α). The aim of this study was to test the hypothesis that TNF-α modulates the interactions of HNSCC cell line PCI-13 and bone marrow mesenchymal stromal cells (BMSCs) and influences markers of epithelial-mesenchymal transition (EMT). Following induction with TNF-α, mono- and co-cultures of BMSCs and the established HNSCC cell line PCI-13 were analyzed; protein expression of E-cadherin and vimentin and qRT-PCR expression of Snail, Twist, MMP14, vimentin, E-cadherin, and ß-catenin were examined, and changes in cellular AKT signalling were analyzed. TNF-α induced a significant decrease in E-cadherin (64.5±6.0%, P=0.002) and vimentin (10.4±3.5%, P=0.04) protein expression in co-cultured PCI-13, while qRT-PCR showed a significant increase in ß-catenin (BMSCs P<0.0001; PCI-13 P=0.0005) and Snail (BMSCs P=0.009; PCI-13 P=0.01). TNF-α also resulted in a down-regulation of AKT downstream targets S6 (38.7±20.9%, P=0.01), p70S6 (16.7±12%, P=0.05), RSK1 (23.6±28.8%, P=0.02), and mTOR (27.4±17.5%, P=0.004) in BMSC co-cultures. In summary, while reducing the expression of vimentin and AKT-signalling in PCI-13 and BMSC, respectively, TNF-α introduced an inflammatory-driven tumour-stroma transition, marked by an increased expression of markers of EMT.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Células-Tronco Mesenquimais , Neoplasias Bucais , Intervenção Coronária Percutânea , Linhagem Celular Tumoral , Técnicas de Cocultura , Transição Epitelial-Mesenquimal , Humanos , Fator de Necrose Tumoral alfa
3.
Int J Oral Maxillofac Surg ; 48(3): 347-354, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30220486

RESUMO

Face-bow transfer is an essential step in articulator-based orthognathic surgery planning. However, it can be a source of inaccuracy. Virtual computer-based planning avoids this error through the use of direct patient-related three-dimensional imaging data. The aim of this prospective observational study was to determine the error of face-bow transfer three-dimensionally and correlate it to the different types of malocclusion. Orthognathic surgery performed on 38 patients (10 male, 28 female; mean (standard deviation) age 24.7 (6.9) years) was planned twice: first articulator-based with plaster models and second computer-based with surgery planning software. Both models were digitized and compared regarding the angle between the Frankfort horizontal plane and the occlusal plane. In most cases, the angle in the sagittal dimension was higher in the articulator-based model than in the computer-based model. The angle in the transverse dimension was as often under- as over-represented. The type of malocclusion, i.e. skeletal class, vertical relationship, and degree of asymmetry, had no significant impact on the amount of error. In conclusion, this study indicates that computer-based planning should be considered as an advantageous alternative in orthognathic surgery planning.


Assuntos
Má Oclusão/cirurgia , Procedimentos Cirúrgicos Ortognáticos/métodos , Cirurgia Assistida por Computador/métodos , Tomografia Computadorizada de Feixe Cônico , Feminino , Humanos , Imageamento Tridimensional , Masculino , Má Oclusão/diagnóstico por imagem , Modelos Dentários , Estudos Prospectivos , Software , Adulto Jovem
4.
Eur Spine J ; 27(6): 1219-1233, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-28940048

RESUMO

PURPOSE: To update findings of the 2000-2010 Bone and Joint Decade Task Force on Neck Pain and its Associated Disorders (Neck Pain Task Force) on the validity and reliability of clinical prediction rules used to screen for cervical spine injury in alert low-risk adult patients with blunt trauma to the neck. METHODS: We searched four databases from 2005 to 2015. Pairs of independent reviewers critically appraised eligible studies using the modified QUADAS-2 and QAREL criteria. We synthesized low risk of bias studies following best evidence synthesis principles. RESULTS: We screened 679 citations; five had a low risk of bias and were included in our synthesis. The sensitivity of the Canadian C-spine rule ranged from 0.90 to 1.00 with negative predictive values ranging from 99 to 100%. Inter-rater reliability of the Canadian C-spine rule varied from k = 0.60 between nurses and physicians to k = 0.93 among paramedics. The inter-rater reliability of the Nexus Low-Risk Criteria was k = 0.53 between resident physicians and faculty physicians. CONCLUSIONS: Our review adds new evidence to the Neck Pain Task Force and supports the use of clinical prediction rules in emergency care settings to screen for cervical spine injury in alert low-risk adult patients with blunt trauma to the neck. The Canadian C-spine rule consistently demonstrated excellent sensitivity and negative predictive values. Our review, however, suggests that the reproducibility of the clinical predictions rules varies depending on the examiners level of training and experience.


Assuntos
Vértebras Cervicais/lesões , Técnicas de Apoio para a Decisão , Programas de Rastreamento/métodos , Traumatismos da Coluna Vertebral/diagnóstico , Adulto , Canadá , Humanos , Lesões do Pescoço/complicações , Cervicalgia/diagnóstico , Reprodutibilidade dos Testes , Medição de Risco/métodos , Sensibilidade e Especificidade , Ferimentos não Penetrantes/complicações
5.
Eur Cell Mater ; 34: 162-179, 2017 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-28980278

RESUMO

The aim of the present study was to evaluate the effect of different dosages of retarded vs. rapid release of bone morphogenic protein 2 (BMP2) at different recipient sites. Porous composite poly(D,L-lactic acid) (PDLLA)/CaCO3 scaffolds were loaded with three different dosages of rhBMP2 (24 µg, 48 µg and 96 µg) and implanted, together with blank controls, both into non-healing defects of the mandibles and into the gluteal muscles of 24 adult male Wistar rats. After 26 weeks, bone formation and expression of bone specific markers [alkaline phosphatase (AP) and Runx2] were evaluated by histomorphometry and immunohistochemistry. Results showed that the mode of delivery had no quantitative effect on bone formation in mandibular sites. Expression of AP and Runx2 showed significant differences among the three dosage groups. There were significant correlations between the expression of both AP and Runx2 as well as the extent of bone formation, with both retarded and rapid release of rhBMP2. In ectopic sites, retarded release significantly enhanced bone formation in the low and medium dosage groups, compared to rapid release. Expression of AP was significantly higher and Runx2 significantly lower in ectopic sites, compared to mandibular sites. Significant correlations between the expression of bone specific markers and bone formation occurred only in the retarded delivery groups, but not in the rapid release groups. Within the limitations of the experimental model, it was concluded that retarded delivery of BMP2 was effective, preferably in sites with low or non-existing pristine osteogenic activity. Expression of bone specific markers indicated that osteogenic pathways might be different in mandibular vs. ectopic sites.


Assuntos
Proteína Morfogenética Óssea 2/farmacologia , Ossos Faciais/efeitos dos fármacos , Mandíbula/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Fator de Crescimento Transformador beta/farmacologia , Fosfatase Alcalina/metabolismo , Animais , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Carbonato de Cálcio/química , Subunidade alfa 1 de Fator de Ligação ao Core/metabolismo , Ossos Faciais/patologia , Masculino , Mandíbula/patologia , Poliésteres/química , Porosidade , Ratos Wistar , Proteínas Recombinantes/farmacologia , Fatores de Tempo , Alicerces Teciduais/química , Resultado do Tratamento
6.
Unfallchirurg ; 120(5): 442-448, 2017 May.
Artigo em Alemão | MEDLINE | ID: mdl-28130573

RESUMO

Concussion injury of the brain is still a frequently underestimated injury, which can be associated with long-lasting consequences. Compared to adults, the recovery phase is often prolonged in childhood. Primary treatment consists of symptom-dependent physical and mental activities. Re-integration into daily life is crucial. In childhood, the primary focus is therefore on returning to school. New symptoms, or an increased presence of symptoms must be detected, to avoid prolonged recovery courses. School restrictions have to be minimized. Corresponding concepts are already implemented in North America. Comparable concepts are not established in Germany. In addition to well-known standard return-to-play protocols for sport re-integration, it is urgently recommended to integrate gradual return-to-learn protocols.Thus, academic adaptations and support must be established as well as symptom-oriented organizational and teaching modules.


Assuntos
Concussão Encefálica/terapia , Papel do Médico , Instituições Acadêmicas/legislação & jurisprudência , Estudantes/legislação & jurisprudência , Cirurgiões/legislação & jurisprudência , Traumatologia/legislação & jurisprudência , Alemanha , Regulamentação Governamental , América do Norte
7.
J Control Release ; 220(Pt A): 201-209, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26485046

RESUMO

The aim of the present study was to test the hypothesis that different amounts of vascular endothelial growth factor and bone morphogenic protein differentially affect bone formation when applied for repair of non-healing defects in the rat mandible. Porous composite PDLLA/CaCO3 carriers were fabricated as slow release carriers and loaded with rhBMP2 and rhVEGF165 in 10 different dosage combinations using gas foaming with supercritical carbon dioxide. They were implanted in non-healing defects of the mandibles of 132 adult Wistar rats with additional lateral augmentation. Bone formation was assessed both radiographically (bone volume) and by histomorphometry (bone density). The use of carriers with a ratio of delivery of VEGF/BMP between 0.7 and 1.2 was significantly related to the occurrence of significant increases in radiographic bone volume and/or histologic bone density compared to the use of carriers with a ratio of delivery of ≤ 0.5 when all intervals and all outcome parameters were considered. Moreover, simultaneous delivery at this ratio helped to "save" rhBMP2 as both bone volume and bone density after 13 weeks were reached/surpassed using half the dosage required for rhBMP2 alone. It is concluded, that the combined delivery of rhVEGF165 and rhBMP2 for repair of critical size mandibular defects can significantly enhance volume and density of bone formation over delivery of rhBMP2 alone. It appears from the present results that continuous simultaneous delivery of rhVEGF165 and rhBMP2 at a ratio of approximately 1 is favourable for the enhancement of bone formation.


Assuntos
Indutores da Angiogênese/administração & dosagem , Conservadores da Densidade Óssea/administração & dosagem , Proteína Morfogenética Óssea 2/administração & dosagem , Carbonato de Cálcio/química , Portadores de Fármacos , Mandíbula/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Poliésteres/química , Fator A de Crescimento do Endotélio Vascular/administração & dosagem , Cicatrização/efeitos dos fármacos , Indutores da Angiogênese/química , Animais , Densidade Óssea/efeitos dos fármacos , Conservadores da Densidade Óssea/química , Proteína Morfogenética Óssea 2/química , Preparações de Ação Retardada , Combinação de Medicamentos , Composição de Medicamentos , Cinética , Masculino , Mandíbula/diagnóstico por imagem , Mandíbula/fisiopatologia , Porosidade , Ratos Wistar , Proteínas Recombinantes/administração & dosagem , Solubilidade , Fatores de Tempo , Fator A de Crescimento do Endotélio Vascular/química
8.
Rev Med Suisse ; 10(447): 1955-6, 1958, 1960, 2014 Oct 22.
Artigo em Francês | MEDLINE | ID: mdl-25518204

RESUMO

The publication in 2009 of the new recom- mandations by the American College of Obstetricians and Gynaecologists (ACOG) about the screening of cervical cancer enabled us to optimize the treatment, especially in young patients. The aim of these modifications is to decrease overtreatment of low grade lesions and thereby the risk of obstetrical complica- tions. The objective of our article is to briefly recall these new guidelines together with a study conducted in our Department of Obstetrics and Gynaecology which aim is to confirm that our practice follows these instructions and to check that these procedures are safe for the future of these young patients.


Assuntos
Programas de Rastreamento/métodos , Guias de Prática Clínica como Assunto , Neoplasias do Colo do Útero/diagnóstico , Fatores Etários , Feminino , Humanos
9.
Clin Pharmacol Ther ; 89(1): 22-4, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21170066

RESUMO

Adolescents naturally experience an increased interest in sexual behavior, but they usually lack much experience. Thus, any prescription medication that holds the potential to ease or facilitate sexual matters holds a unique allure. Widespread cultural awareness of medications to treat erectile dysfunction (ED) has combined with a recent trend toward increased adolescent prescription drug abuse to create unique challenges for industry, clinicians, and researchers.


Assuntos
Analgésicos Opioides/farmacologia , Benzodiazepinas/farmacologia , Entorpecentes/farmacologia , Uso Off-Label/estatística & dados numéricos , Inibidores da Fosfodiesterase 5/farmacologia , Inibidores da Fosfodiesterase 5/uso terapêutico , Comportamento Sexual/efeitos dos fármacos , Adolescente , Comportamento do Adolescente/efeitos dos fármacos , Comportamento do Adolescente/psicologia , Analgésicos Opioides/efeitos adversos , Benzodiazepinas/efeitos adversos , Humanos , Masculino , Meios de Comunicação de Massa/tendências , Entorpecentes/efeitos adversos , Inibidores da Fosfodiesterase 5/efeitos adversos , Assunção de Riscos , Comportamento Sexual/psicologia
10.
Rehabilitation (Stuttg) ; 49(2): 80-6, 2010 Apr.
Artigo em Alemão | MEDLINE | ID: mdl-20446190

RESUMO

Health-related strategies aimed at ensuring long-term participation in working life are gaining increasing importance against a background of longer working lives and demographic change. Medical and vocational rehabilitation under the German statutory pension insurance scheme are among these strategies. For a long time already, preventive concepts have been taken into account in rehabilitation so that the pension insurance's prevention approach is mainly based on the experience gained with preventive-modules in rehabilitation and follow-up care. Having so far only been able to offer in-patient prevention benefits, the statutory pension insurance scheme now can offer out-patient prevention measures, given the amendment it initiated to change Section 31 (1) no. 2 of Book 6 of the German Social Code which came into effect on January 1, 2009. The common guidelines of the statutory pension insurance institutions directed at ensuring continued working capacity were revised relative to the preventive benefits contained and were supplemented by recommendations for their use. The changing occupational demands in modern service society have thus been taken into account, and prevention benefits can be implemented in a more flexible manner following successful trials. The concept of out-patient prevention measures following along at the workplace and during leisure time is intended to enhance sustainability of acquired health-promoting behaviours in every day (working) life. At present this new concept is being tried out in various circumscribed pilot projects by several pension insurance institutions, partly in combination with in-patient components. On account of their specific know-how and their regional networks with enterprises, rehabilitation facilities are destined as locations for carrying out pension insurance prevention benefits.


Assuntos
Doença Crônica/prevenção & controle , Doença Crônica/reabilitação , Promoção da Saúde/legislação & jurisprudência , Programas Nacionais de Saúde/legislação & jurisprudência , Educação de Pacientes como Assunto/legislação & jurisprudência , Reabilitação Vocacional/métodos , Previdência Social/legislação & jurisprudência , Assistência ao Convalescente , Assistência Ambulatorial , Terapia Combinada , Alemanha , Humanos , Estilo de Vida , Doenças Profissionais/prevenção & controle , Doenças Profissionais/reabilitação , Admissão do Paciente , Projetos Piloto , Prevenção Secundária
11.
J Neurochem ; 102(2): 479-92, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17419810

RESUMO

Nicotinic acetylcholine receptors play important roles in numerous cognitive processes as well as in several debilitating central nervous system (CNS) disorders. In order to fully elucidate the diverse roles of nicotinic acetylcholine receptors in CNS function and dysfunction, a detailed knowledge of their cellular and subcellular localizations is essential. To date, methods to precisely localize nicotinic acetylcholine receptors in the CNS have predominantly relied on the use of anti-receptor subunit antibodies. Although data obtained by immunohistology and immunoblotting are generally in accordance with ligand binding studies, some discrepancies remain, in particular with electrophysiological findings. In this context, nicotinic acetylcholine receptor subunit-deficient mice should be ideal tools for testing the specificity of subunit-directed antibodies. Here, we used standard protocols for immunohistochemistry and western blotting to examine the antibodies raised against the alpha3-, alpha4-, alpha7-, beta2-, and beta4-nicotinic acetylcholine receptor subunits on brain tissues of the respective knock-out mice. Unexpectedly, for each of the antibodies tested, immunoreactivity was the same in wild-type and knock-out mice. These data imply that, under commonly used conditions, these antibodies are not suited for immunolocalization. Thus, particular caution should be exerted with regards to the experimental approach used to visualize nicotinic acetylcholine receptors in the brain.


Assuntos
Anticorpos/metabolismo , Especificidade de Anticorpos/imunologia , Imuno-Histoquímica/métodos , Neuroquímica/métodos , Subunidades Proteicas/imunologia , Receptores Nicotínicos/imunologia , Acetilcolina/metabolismo , Animais , Animais Recém-Nascidos , Anticorpos/química , Western Blotting , Bungarotoxinas/metabolismo , Córtex Cerebral/anatomia & histologia , Córtex Cerebral/imunologia , Córtex Cerebral/metabolismo , Eletroforese em Gel Bidimensional , Feminino , Hipocampo/anatomia & histologia , Hipocampo/imunologia , Hipocampo/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/imunologia , Neurônios/metabolismo , Subunidades Proteicas/análise , Subunidades Proteicas/genética , Receptores Nicotínicos/análise , Receptores Nicotínicos/genética , Transmissão Sináptica/imunologia
12.
Anaesthesist ; 55(10): 1099-104, 2006 Oct.
Artigo em Alemão | MEDLINE | ID: mdl-16850326

RESUMO

BACKGROUND: Transport of blood gas samples via a pneumatic tube system and subsequent analysis in the central laboratory can reduce costs and errors compared to on-site testing in the operating theatre or the intensive care unit. In this study, a modern pneumatic tube transport system was tested for its usability for this purpose. METHODS: A total of 4 consecutive blood gas samples were obtained intraoperatively from 54 different patients and sent to the central laboratory. Of these, 3 samples were transferred using the pneumatic tube system but by different methods and 1 sample was transported personally which served as a reference. The results of sample analysis concerning blood gases, electrolytes and haemoglobin were compared and examined for differences. RESULTS: No statistically significant differences could be determined between the different modes of transportation. CONCLUSION: Transport of samples for blood gas analysis via a modern pneumatic tube system is safe when samples are correctly prepared.


Assuntos
Gasometria/métodos , Laboratórios Hospitalares/organização & administração , Análise de Variância , Gasometria/instrumentação , Dióxido de Carbono/sangue , Eletrólitos/sangue , Hemoglobinas/análise , Humanos , Monitorização Intraoperatória , Salas Cirúrgicas , Análise de Regressão , Reprodutibilidade dos Testes , Manejo de Espécimes
13.
Eur J Clin Invest ; 33(3): 256-60, 2003 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-12641545

RESUMO

BACKGROUND: Quantitative analyses of PTEN expression of ovarian cancer tissues were performed in this study. PTEN expression was investigated in terms of each patient's progression-free interval to indicate the role of PTEN in the generation of platinum refractory tumours. MATERIALS AND METHODS: The study group comprised 20 ovarian cancer patients from whom fresh frozen tissues of both the primary tumour and specimens of progressive disease were available. The PTEN protein and phosphorylation of the downstream effector protein kinase B (PKB) were quantified by Western blot analyses and subsequent densitometry. Data were analyzed for individual PTEN variation with respect to the clinical course as defined by the progression-free interval. RESULTS: Applying the usual clinical criteria for platinum-sensitivity after progression, seven patients were considered platinum-sensitive whereas 13 patients had suffered a progression within 12 months after the chemotherapy. In 5/7 (71%) cases with prolonged time to progression, an increase in PTEN was observed. Decline of PTEN expression occurred in 9/13 (69%) patients with poor outcome. PTEN expression corresponds inversely to PKB phosphorylation in 14/20 (70%) tissues investigated. CONCLUSIONS: The data suggest that decreased PTEN expression accompanies the progression of ovarian cancer. Declining PTEN expression results in a shortened relapse-free interval, whereas an increase of PTEN prolongs the time to progression. However, as far as recurrence occurs, PTEN is not the only mechanism to suppress tumour progression in ovarian cancer.


Assuntos
Neoplasias Ovarianas/metabolismo , Monoéster Fosfórico Hidrolases/metabolismo , Proteínas Serina-Treonina Quinases , Proteínas Supressoras de Tumor/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Western Blotting , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/etiologia , PTEN Fosfo-Hidrolase , Monoéster Fosfórico Hidrolases/isolamento & purificação , Fosforilação , Proteínas Proto-Oncogênicas/isolamento & purificação , Proteínas Proto-Oncogênicas c-akt , Proteínas Supressoras de Tumor/isolamento & purificação
14.
Brain Res Dev Brain Res ; 132(1): 33-45, 2001 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-11744105

RESUMO

Nicotinic acetylcholine receptors are likely to play an important role in neuronal migration during development. Furthermore, the alpha4 receptor subunit gene is related to a hereditary juvenile form of epilepsy. Only little information is available, however, on the expression of cerebrocortical nicotinic acetylcholine receptors during human fetal development. Using non-isotopic in situ hybridization and immunohistochemistry, we have studied the distribution of the alpha4 subunit of the nicotinic acetylcholine receptor mRNA and protein in the human frontal cortex at middle (17-24 weeks of gestation) and late (34-42 weeks of gestation) fetal stages. Both, alpha4 receptor mRNA and alpha4 receptor protein were observed beginning during week 17-18 of gestation. At this time of development, a few weakly labeled mRNA-containing cells were present mainly in the ventricular zone, the subplate and the cortical plate. A similar distribution pattern was found for the receptor protein. Around week 38 of gestation, the distribution in the cerebral cortex of alpha4 subunit-containing cells was similar to that of adult human cortices with the highest densities of labeled neurons found in layers II/III, followed by layers V and VI. Nicotinic acetylcholine receptor-containing neurons appear rather early in human fetal development. Given functional maturity, they may interact during cortical development with acetylcholine released from corticopetal fibers or other yet unknown sources subserving the process of neuronal migration and pathfinding.


Assuntos
Córtex Cerebral/embriologia , Regulação da Expressão Gênica no Desenvolvimento , Receptores Nicotínicos/genética , Animais , Córtex Cerebral/química , Feminino , Idade Gestacional , Humanos , Imuno-Histoquímica , Hibridização In Situ , Masculino , Oócitos/fisiologia , RNA Mensageiro/análise , Receptores Nicotínicos/análise , Xenopus
15.
J Chem Neuroanat ; 21(3): 239-46, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-11382535

RESUMO

Cholinergic fibers from the basal forebrain are known to contact cholinoceptive cortical pyramidal neurons. Recent electrophysiological studies have revealed that nicotinic acetylcholine receptors are also present in human cerebrocortical interneurons. A direct visualization of nicotinic receptor subunits in cortical interneurons has, however, not yet been performed. We have applied double-immunofluorescence using antibodies against parvalbumin --a marker for the Chandelier and basket cell subpopulation of interneurons--and to the alpha4 and alpha7 subunit proteins of the nicotinic acetylcholine receptor. The vast majority of the parvalbuminergic interneurons was immunoreactive for the alpha4 and the alpha7 nicotinic acetylcholine receptor. Provided these receptors would be functional--as suggested by recent electrophysiological findings--the connectivity pattern of cholinergic afferents appears much more complex than thought before. Not only direct cholinergic impact on cortical projection neurons but also the indirect modulation of these by cholinergic corticopetal fibers contacting intrinsic cortical cells would be possible.


Assuntos
Córtex Cerebral/química , Interneurônios/química , Parvalbuminas/análise , Receptores Nicotínicos/análise , Adulto , Idoso , Córtex Cerebral/metabolismo , Feminino , Humanos , Interneurônios/metabolismo , Masculino , Pessoa de Meia-Idade , Parvalbuminas/metabolismo , Receptores Nicotínicos/metabolismo , Receptor Nicotínico de Acetilcolina alfa7
16.
Behav Brain Res ; 113(1-2): 207-15, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10942047

RESUMO

Nicotinic ligand binding studies have shown rather early that the cholinoceptive system is affected in Alzheimer's disease (AD). Today, molecular histochemistry enables one to study the nicotinic acetylcholine receptor (nAChR) subunit expression on the cellular level in human autopsy brains, in animal models and in in vitro approaches, thus deciphering the distribution of nAChRs and their role as potential therapeutic targets. The studies on the nAChR expression in the frontal and temporal cortex of AD patients and age-matched controls could demonstrate that both, the numbers of alpha4- and alpha7-immunoreactive neurons and the quantitative amount, in particular of the alpha4 protein, were markedly decreased in AD. Because the number of the corresponding mRNA expressing neurons was unchanged these findings point to a translational/posttranslational rather than a transcriptional event as an underlying cause. This assumption is supported by direct mutation screening of the CHRNA4 gene which showed no functionally important mutations. To get more insight into the underlying mechanisms, two model systems organotypic culture and primary hippocampal culture - have been established, both allowing to mimic nAChR expression in vitro. In ongoing studies the possible impact of beta-amyloid (Abeta) on nAChR expression is tested. Preliminary results obtained from primary cultures point to an impaired nAChR expression following Abeta exposure.


Assuntos
Doença de Alzheimer/patologia , Encéfalo/patologia , Receptores Nicotínicos/análise , Idoso , Idoso de 80 Anos ou mais , Peptídeos beta-Amiloides/análise , Células Cultivadas , Córtex Cerebral/patologia , Feminino , Lobo Frontal/patologia , Hipocampo/patologia , Humanos , Masculino , Neurônios/patologia , Receptor Nicotínico de Acetilcolina alfa7
18.
Acta Neurol Scand Suppl ; 176: 42-8, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11261804

RESUMO

OBJECTIVE: Our autopsy studies show possible links between classical Alzheimer pathology and decreased expression of nicotinic acetylcholine receptors. For further elucidation we are now using in vitro models. We report preliminary evidence for the impact of beta-amyloid on nicotinic receptor expression in hippocampal dissociation culture. METHODS: Cultures (E18 rats) were grown in a serum-free medium and incubated at 8 days in vitro for 3 days with 1 microM Abeta1-42. Expression of alpha4, alpha7, and beta2 nicotinic receptor subunit protein was assessed immunohistochemically and rated semiquantitatively. RESULTS: Abeta1-42 incubation resulted in a massive reduction of alpha4 protein-expressing neurons, this effect was less pronounced for the alpha7 and beta2 subunit protein. CONCLUSION: These findings provide first evidence for a direct impact of classical Alzheimer pathology features on nicotinic receptor expression in vitro. Our model will be useful for testing the potential of drugs to stop or reverse these effects.


Assuntos
Doença de Alzheimer/fisiopatologia , Peptídeos beta-Amiloides/farmacologia , Receptores Nicotínicos/fisiologia , Animais , Técnicas de Cultura de Células , Modelos Animais de Doenças , Regulação da Expressão Gênica , Hipocampo/patologia , Imuno-Histoquímica , Neurônios/fisiologia , Ratos , Ratos Wistar
19.
Schweiz Med Wochenschr ; 128(22): 880-6, 1998 May 30.
Artigo em Alemão | MEDLINE | ID: mdl-9653826

RESUMO

"Digest" is a international effort to record the prevalence of digestive symptoms in the general population. The international questionnaire was tested in German translation for reliability and reproducibility. The questionnaire consists of 14 symptoms, which were investigated by standardized questions. Each symptom was described in 3 dimensions: frequency, severity and impact on daily activities. 127 successive patients referred for upper gastrointestinal endoscopy were interviewed twice by a young assistant and by an experienced gastroenterologist before the diagnostic work-up. A further 72 volunteers served as a control group. In these volunteers no upper gastrointestinal endoscopy was performed. Reliability and reproducibility were calculated by the Spearman rank test. The most frequent diagnoses were: organic diseases (oesophagitis [28], gastric ulcer/erosive gastritis [32] and duodenal ulcer [18]); functional diseases (dyspepsia [32] and irritable bowel syndrome [14]). Reproducibility was satisfactory by accepted standards (p > 0.7). Reliability was very good, with r-values for each symptom between p 0.96-0.99. The impact on daily activities was highest in the case of heart-burn or localized upper gastrointestinal pain, and lowest in the case of belching and fullness. The questionnaire can be easily administered by the non-specialist and the results discriminate well between functional/organic diseases and healthy people, thanks to excellent reproducibility and reliability.


Assuntos
Gastroenteropatias/epidemiologia , Inquéritos e Questionários , Atividades Cotidianas/classificação , Adulto , Idoso , Estudos Transversais , Diagnóstico Diferencial , Feminino , Gastroenteropatias/diagnóstico , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Qualidade de Vida , Reprodutibilidade dos Testes , Transtornos Somatoformes/diagnóstico , Transtornos Somatoformes/epidemiologia , Suíça/epidemiologia
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