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1.
Int J Oral Maxillofac Surg ; 50(9): 1210-1218, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33602648

RESUMEN

In this study we compared the aesthetic outcome of (1) Le Fort I (LFI) osteotomy and (2) intraoral quadrangular Le Fort II (IQLFII) osteotomy for surgical correction of skeletal class III dysgnathia involving midfacial deficiency. The aim was to investigate whether laypersons see differences in facial changes that occur due to variations of the osteotomy cuts. The patient collectives consisted of 23 patients in each group. Pre- and postoperative photographs were presented in a random sequence to 40 layperson raters. The rating procedure was conducted with a four-point Likert scale. Assessed characteristics were 'attractiveness' ('Attraktivität'), 'likeability' ('Sympathie'), 'intelligence' ('Intelligenz'), 'aggressiveness' ('Aggressivität') and 'dominance' ('Dominanz'). For preoperative photographs we found a significant difference for 'likeability' with lower ratings for the IQLFII group; all other criteria were rated similarly. For the IQLFII group we found a significantly larger shift from lower to higher ratings for 'attractiveness' and 'likeability' and a significantly larger shift from higher to lower ratings for 'aggressiveness' and 'dominance' than for the LF I group. Our study shows that lay raters detect significant differences between the two surgical groups. Thus, IQLFII osteotomy, when indicated, represents a favourable alternative to conventional LFI osteotomy, if patients desire the expectable change in recognition by their social circle.


Asunto(s)
Labio Leporino , Fisura del Paladar , Cefalometría , Estética Dental , Cara , Humanos , Maxilar/cirugía , Osteotomía Le Fort
4.
Artículo en Inglés | MEDLINE | ID: mdl-21310356

RESUMEN

BACKGROUND: Osteosynthesis failure rates of 11.3% with 1 miniplate, 6.7% with 2 miniplates, and 4.4% with a single Medartis condyle plate were reported in previous studies of our clinic. Current science is still focused on the osteosynthesis material. Besides clinical parameters, conventional radiographs are still the first choice to detect osteosynthesis failures. This study scrutinized several factors assessable in postoperative orthopantomographs which might elevate the risk of osteosynthesis failure. STUDY DESIGN: A total of 136 patients (22 with osteosynthesis failure, 114 without) with 151 mandibular condyle fractures were included in this study. Eight parameters were assessed in postoperative orthopantomographs. RESULTS: The best predictor of osteosynthesis failure was a simplified concept of ramus height. In cases of reduced or normal ramus height, the odds of osteosynthesis failure was significantly (P = .000001) reduced to a 10th. Isolated fractures were significantly more error prone (P = .0009). CONCLUSIONS: Postoperative orthopantomographs depict factors which increase the risk of osteosynthesis failure.


Asunto(s)
Fijación Interna de Fracturas/métodos , Cóndilo Mandibular/lesiones , Fracturas Mandibulares/cirugía , Radiografía Panorámica , Cuidados Posteriores , Fenómenos Biomecánicos , Placas Óseas , Cefalometría/métodos , Estudios de Cohortes , Endoscopía , Estudios de Seguimiento , Predicción , Humanos , Cóndilo Mandibular/diagnóstico por imagen , Cóndilo Mandibular/cirugía , Fracturas Mandibulares/diagnóstico por imagen , Radiografía Panorámica/métodos , Estudios Retrospectivos , Rotación , Factores de Tiempo , Insuficiencia del Tratamiento
5.
Dtsch Med Wochenschr ; 132(24): 1315-20, 2007 Jun 15.
Artículo en Alemán | MEDLINE | ID: mdl-17551885

RESUMEN

BACKGROUND AND OBJECTIVE: Approximately six million Germans have been diagnosed with diabetes mellitus. A continuously increasing number of people with diabetes is expected within the next few years. Genetic disposition, age and especially lifestyle play an important role in the development of the disease. Diabetes normally develops during a long preclinical phase. During this preclinical phase an impaired glucose tolerance can easily be detected. Since an impaired glucose tolerance is often reversible the onset of diabetes can be prevented effectively by a change of lifestyle during this phase. The Bavarian Red Cross Blood Transfusion Service therefore determined the diabetes risk among its blood donors during two one-week study periods. PATIENTS AND METHODS: The diabetes risk of the participating donors was assessed by using the FindRisk diabetes test published by the German Diabetes Foundation and the HbA1c test. RESULTS: Approximately 12 percent of the participants (8187 persons aged 18-68 years) showed a moderate, high or even very high risk of developing diabetes within the next 10 years. The probability of developing the disease ranged from 17% (moderate risk) to 50% (very high risk). This corresponds to 3% of persons with unknown diabetes among the total population. An elevated HbA1c was found in approximately 5% of the donors in the first study week and in approximately 19% in the second study week. The analysis of the questionnaire and the HbA1c results indicated that elevated HbA1c values correlate with known diabetes risk factors. Persons with a body mass index greater than 25, an increased score in the FindRisk questionnaire and aged over 50 years more frequently showed an elevated HbA1c value. CONCLUSIONS: The combination of a diabetes risk questionnaire and HbA1c testing could be used successfully for diabetes screening in an identified risk group.


Asunto(s)
Donantes de Sangre , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/diagnóstico , Hemoglobina Glucada/análisis , Adolescente , Adulto , Anciano , Diabetes Mellitus Tipo 2/epidemiología , Diabetes Mellitus Tipo 2/etiología , Femenino , Alemania/epidemiología , Humanos , Estilo de Vida , Masculino , Tamizaje Masivo , Persona de Mediana Edad , Medición de Riesgo/métodos , Factores de Riesgo , Encuestas y Cuestionarios
6.
Int J Oral Maxillofac Surg ; 34(3): 262-7, 2005 May.
Artículo en Inglés | MEDLINE | ID: mdl-15741034

RESUMEN

The purpose of this study was to assess the prognostic value of histological response to preoperative radiochemotherapy in an established multimodal therapy concept for advanced oral and oropharyngeal cancer. Two hundred and twenty-two patients who underwent preoperative radiochemotherapy (RCT: 50 Gy, mitomycin C and fluorouracil) and radical surgery were retrospectively evaluated. Resected tumours of all patients were histologically analysed and response to RCT was classified in histopathological grades of regression (RG). In a multivariate statistical analysis, RG was compared with established factors regarding their predictive value for overall and disease-specific survival. The 5-year overall survival probability in the different groups of histopathological regression grades were: RG1 (no vital tumour): 73.4%, RG2 (minimal tumour remnants encompassing less than 5%): 72.1%, RG3 (5-50% vital tumour cells): 41.9%, RG4 (more than 50% vital tumour): 37.9%. For disease-specific survival probability no significant differences were found between both groups of "responders" (RG1 and RG2) nor between "non-responders" (RG3 and RG4), whereas responders and non-responders differed significantly from each other (log-rank test; p < 0.001). T-classification, N-classification and disease stage, histological grading, tumour site, age, and sex had less prognostic value than RG in a Cox regression model. In the neoadjuvant multimodal therapy concept, histological response to preoperative RCT is a crucial prognostic factor even when surgical R0-resection is accomplished. Thus, non-responders have to be regarded as high-risk patients for recurrence and may benefit from further therapy.


Asunto(s)
Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Neoplasias de la Boca/patología , Neoplasias de la Boca/terapia , Terapia Neoadyuvante , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioterapia Adyuvante , Femenino , Fluorouracilo/administración & dosificación , Humanos , Masculino , Persona de Mediana Edad , Mitomicina/administración & dosificación , Neoplasias de la Boca/mortalidad , Neoplasias de la Boca/cirugía , Análisis Multivariante , Estadificación de Neoplasias , Neoplasia Residual/patología , Neoplasias Orofaríngeas/mortalidad , Neoplasias Orofaríngeas/patología , Neoplasias Orofaríngeas/cirugía , Neoplasias Orofaríngeas/terapia , Pronóstico , Modelos de Riesgos Proporcionales , Dosis de Radiación , Radioterapia Adyuvante , Estudios Retrospectivos , Análisis de Supervivencia
7.
Int J Oral Maxillofac Surg ; 34(2): 143-8, 2005 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15695042

RESUMEN

To analyse survival and locoregional control in patients with advanced oral and oropharyngeal squamous cell carcinoma (SCC) after multimodal therapy with preoperative radiochemotherapy (RCT) and radical surgery. We included in this analysis 222 patients who underwent multimodal therapy between 1990 and 2000. Eligible were patients with UICC disease stages II-IV (T2: 33.3%; T3: 12.6%; T4: 54.1%; N0: 45.9%; N1: 17.6%; N2: 33.3%; N3: 3.2%; stage II: 21.1%; stage III: 14.9%; stage IV: 64%). Patients received preoperative radiochemotherapy consisting of Mitomycin C (15-20 mg/m2, day 1) plus 5-Fluorouracil (750 mg/m2/24 h-infusion, days 1-5) and concomitant radiotherapy for a total dose of 50 Gy. Radical locoregional en bloc-resection according to the pretherapeutic tumour extension was carried out in all patients. After a median surveillance period of 72.3 months (24-152 months), 131 patients (59%) were alive, and 91 (41%) patients died; 12 (5%) of them died postoperatively, 46 (21%) due to tumour recurrence, and 33 (15%) deaths were not directly related to the primary tumour. Overall survival probability was 76% after 2 years, and 62% after 5 years. Two- and 5-year local control probability were 88 and 81%, respectively. Regarding the high percentage of stage IV disease in the reported patients, the multimodal concept is an effective therapy offering excellent survival and local control probability.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Neoplasias de la Boca/cirugía , Terapia Neoadyuvante , Neoplasias Orofaríngeas/cirugía , Antibióticos Antineoplásicos/administración & dosificación , Antimetabolitos Antineoplásicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/radioterapia , Carcinoma de Células Escamosas/secundario , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Mitomicina/administración & dosificación , Neoplasias de la Boca/tratamiento farmacológico , Neoplasias de la Boca/radioterapia , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Neoplasias Orofaríngeas/tratamiento farmacológico , Neoplasias Orofaríngeas/radioterapia , Dosificación Radioterapéutica , Estudios Retrospectivos , Tasa de Supervivencia , Resultado del Tratamiento
8.
Int J Oral Maxillofac Surg ; 33(6): 554-7, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15308254

RESUMEN

The clinical outcome of two stage reconstruction with revascularized grafts after resection of extensive retromolar and oropharyngeal squamous cell carcinoma in 17 patients is presented. In the first operation, the intraoral soft tissue defect was covered by a revascularized jejunal flap, and the mandibular defect was bridged by a reconstruction plate. After a period of 5-28 months, mandibular reconstruction was performed with a microsurgically revascularized iliac crest graft that was positioned under the jejunal graft. Clinical follow up included tumour recurrence rate, the form of nutrition, speech disorders and mouth opening restrictions. Quality of life was analysed by the EORTC questionnaires. Fifteen patients were free of recurrence and alive. Twelve patients were able to swallow food. The jejunal flap provided perfect lining of the soft palate, the pharynx and the base of the tongue, thus supporting functional restoration. Despite the gravity of disease and invasiveness of therapy, the two stage procedure leads to satisfying functional and aesthetic results thus obtaining appropriate QOL.


Asunto(s)
Trasplante Óseo/métodos , Carcinoma de Células Escamosas/rehabilitación , Neoplasias Mandibulares/rehabilitación , Procedimientos Quirúrgicos Orales/métodos , Neoplasias Orofaríngeas/rehabilitación , Colgajos Quirúrgicos , Adulto , Placas Óseas , Carcinoma de Células Escamosas/cirugía , Arterias Carótidas , Femenino , Humanos , Yeyuno/trasplante , Masculino , Neoplasias Mandibulares/cirugía , Persona de Mediana Edad , Neoplasias Orofaríngeas/cirugía , Calidad de Vida , Colgajos Quirúrgicos/irrigación sanguínea , Resultado del Tratamiento
9.
Int J Oral Maxillofac Surg ; 32(3): 257-62, 2003 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12767871

RESUMEN

This retrospective study quantifies isolated orbital floor fractures using software-based CT-analysis and compares the clinical outcome across surgical and non-surgical treatment groups. Depending on the surgeon's interpretation of the clinical and radiological appearance, 10 fractures were treated non-surgically and 20 fractures surgically, either with antral balloon catheter alone or in combination with an orbital implant. Ophthalmologic findings were evaluated until 12 weeks after injury. Fracture area, and volume of displaced tissue (VDT) were assessed by software-based CT-analysis. VDT was marginally significantly smaller in non-surgically than in surgically-treated patients (P=0.08). Ophthalmologic findings improved in all groups during follow-up and no statistical difference was found between the groups. Diplopia remained moderate in three patients with balloon catheter alone, and minimal in four patients in both surgical groups. In one patient with non-surgical treatment, diplopia remained minimal after 12 weeks. Although CT-analysis revealed no significant difference between both surgical groups, patients treated with balloon catheter alone presented more diplopia after 12 weeks. Using balloon catheters for fracture repair a combined approach should be performed when large fractures involve the orbital floor to achieve sufficient reduction of orbital content and placement of an orbital implant. Software-based CT-analysis is helpful for objective interpretation in managing of orbital fractures.


Asunto(s)
Fracturas Orbitales/terapia , Adulto , Anciano , Cateterismo , Diplopía/etiología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Trastornos de la Motilidad Ocular/etiología , Fracturas Orbitales/complicaciones , Fracturas Orbitales/diagnóstico por imagen , Fracturas Orbitales/cirugía , Implantes Orbitales , Estudios Retrospectivos , Programas Informáticos , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
10.
Int J Oral Maxillofac Surg ; 32(2): 159-66, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-12729776

RESUMEN

In the present work two methods of harvesting the RFFF (radial free forearm flap) are compared: the prelaminated fasciomucosal and the non-prelaminated fasciocutaneous version. The flaps were employed for intraoral reconstruction after radical oncological surgery of the oral cavity. In most cases a squamous cell carcinoma was the present malignant tumour. A total of 32 patients were included in the study, 16 in each group. The design was retrospective. Data were obtained by clinical follow up, chart review and compiled database. Analysis included the amount of shrinkage of the flaps during the follow-up period, early postoperative complications, following function improving operations and early and late donor site difficulties. Prelaminated fasciomucosal flaps showed a higher shrinkage rate than fasciocutaneous non-prelaminated flaps. Due to this circumstance the number of following function improving operations was higher in the prelaminated flap group. Early wound healing difficulties were also seen more often in the prelaminated flap group, whereas donor site problems occurred more frequently in the non-prelaminated group. Mucosal prelamination of the RFFF is a promising method for a most physiological reconstruction of intraoral defects resulting from tumour surgery. Postoperative shrinkage is a problem in prelaminated RFFF. Our aim is to improve the prelamination technique in order to prevent shrinkage. The almost complete absence of donor site difficulties in prelaminated RFFF may represent a solution to this common and yet unsolved problem.


Asunto(s)
Fascia/trasplante , Mucosa Bucal/trasplante , Trasplante de Piel/métodos , Colgajos Quirúrgicos/clasificación , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/cirugía , Fascia/patología , Femenino , Estudios de Seguimiento , Antebrazo , Supervivencia de Injerto , Humanos , Masculino , Membranas Artificiales , Persona de Mediana Edad , Mucosa Bucal/patología , Neoplasias de la Boca/cirugía , Complicaciones Posoperatorias , Estudios Retrospectivos , Colgajos Quirúrgicos/patología , Infección de la Herida Quirúrgica/etiología , Recolección de Tejidos y Órganos/métodos , Cicatrización de Heridas
11.
Int J Oral Maxillofac Surg ; 31(6): 664-9, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12521326

RESUMEN

This study reports the findings of an evaluation of Quality of Life (QOL) in long-term survivors of advanced oral and oropharyngeal cancer treated with preoperative chemoradiotherapy followed by surgery (combined treatment=multimodal therapy). All patients had T2-T4 tumours and all received locoregional radical resection and simultaneous microvascular reconstruction. From 1990 to 1998, 181 patients have been treated at the University Hospital of Cranio-Maxillofacial and Oral Surgery in Vienna. 100 (55%) of these patients were alive and free of disease in 2000. Sixty-seven of them completed the EORTC questionnaires QLQ 30 and QLQ H&N 35. We found these questionnaires to be very good tools for determining QOL, which constitutes part of the therapeutic success. Patients tended to report good to very good QOL. A comparison between groups according to clinical data was conducted as well as a group comparison of patients who claimed especially high or low QOL in the questionnaires. It was found that combined treatment not only offers the best chances for survival, but also allows a subsequent QOL, that is comparable to other forms of therapy.


Asunto(s)
Carcinoma de Células Escamosas/cirugía , Neoplasias de la Boca/cirugía , Neoplasias Orofaríngeas/cirugía , Calidad de Vida , Antibióticos Antineoplásicos/administración & dosificación , Antimetabolitos Antineoplásicos/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Quimioterapia Adyuvante , Terapia Combinada , Supervivencia sin Enfermedad , Femenino , Fluorouracilo/administración & dosificación , Estudios de Seguimiento , Humanos , Estudios Longitudinales , Masculino , Microcirugia , Persona de Mediana Edad , Mitomicina/administración & dosificación , Disección del Cuello , Estadificación de Neoplasias , Radioterapia Adyuvante , Análisis de Regresión , Estadísticas no Paramétricas , Colgajos Quirúrgicos , Encuestas y Cuestionarios , Resultado del Tratamiento
12.
J Oral Maxillofac Surg ; 59(12): 1437-42, 2001 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11732031

RESUMEN

PURPOSE: A computer program recently developed for the calculation of the orbital floor and fracture areas from coronal computed tomography (CT) scans was used in a study to evaluate the accuracy and ability of this new method. MATERIAL AND METHODS: The size of orbital floors and fabricated fractures in 14 dried, anatomic specimens were measured in coronal CT scans by 3 independent observers. Based on this data set, the orbital floor and fracture regions were calculated with the newly developed computer program. These calculated regions were then compared with a direct measurement of the specimens that had been obtained by digital photography. The accuracy of the computer-based calculations was assessed using Lin's concordance correlation coefficient. RESULTS: The size of the orbital floor (mean +/- SD) was found to be 5.21 +/- 0.39 cm(2) by direct measurement of the specimens and 5.30 +/- 0.52 cm(2) by calculation with the computer program. The region of the fracture (mean +/- SD) was 1.05 +/- 0.64 cm(2) by direct measurement and 1.01 +/- 0.62 cm(2) by computer calculation. The between-method mean difference (direct measurement minus computer based calculation) was -0.09 cm(2) (or 1.7% of mean orbital floor region) for orbital floor region and 0.04 cm(2) (or 3.8% of mean fracture region) for fracture region. CONCLUSIONS: This accurate and time-saving method is practicable for determining the size and location of orbital floor fractures. This calculation program can be advantageously applied in the clinical management of blowout fractures of the orbit.


Asunto(s)
Fracturas Orbitales/diagnóstico por imagen , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Tomografía Computarizada por Rayos X/métodos , Algoritmos , Humanos , Reproducibilidad de los Resultados , Validación de Programas de Computación
13.
J Oral Maxillofac Surg ; 59(11): 1302-8; discussion 1309-10, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11688032

RESUMEN

PURPOSE: Vertical osteodistraction is a new alternative method for alveolar ridge augmentation of the mandible. The purpose of this article is describe a technique using an L-shaped osteotomy and titanium membranes for guided bone regeneration (GBR) in the distraction gap. PATIENTS AND METHODS: Ten patients with severe atrophy of the edentulous molar region of the mandible underwent vertical callus distraction in 13 sites using intraoral microplate distractors. An L-shaped osteotomy with a short vertical part mesially and a longer horizontal part ending in the retromolar region was made, and the osteotomized segment was fixed to the mandibular ramus at its distal edge by a microplate, which became the center of rotation when distraction began. In this way, more callus generation could be achieved mesially than in the distal molar region. Follow-up computed tomography (CT) scans reconstructed axially to the axis of the mandible revealed semilunar excavations of the generated bone buccally in the distraction gap in the first cases. Clinical inspection on removal of the distractors showed fibrous connective tissue in the gap. Therefore, to prevent this from happening, titanium membranes covering the distraction gap were applied in subsequent cases. RESULTS: Ten patients (13 sites) were treated by vertical callus distraction. In 4 cases, GBR was achieved using titanium membranes. In all cases, the increase in alveolar height was sufficient to make dental implantation possible. In 1 patient, a fracture of the distractor occurred, and dehiscence was observed in 2 cases. These complications did not change the plan of therapy nor did they influence the results. The CT scans showed a homogenous surface on the regenerated mandible in the cases of GBR application. CONCLUSION: Both an L-shaped osteotomy and the application of titanium membranes for GBR in the distraction gap are of great value for mandibular augmentation, producing a physiologically shaped alveolar ridge.


Asunto(s)
Aumento de la Cresta Alveolar/métodos , Regeneración Tisular Guiada Periodontal/métodos , Mandíbula/cirugía , Membranas Artificiales , Osteogénesis por Distracción/métodos , Adulto , Anciano , Pérdida de Hueso Alveolar/rehabilitación , Pérdida de Hueso Alveolar/cirugía , Aumento de la Cresta Alveolar/instrumentación , Implantación Dental Endoósea , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Osteogénesis por Distracción/instrumentación , Osteotomía/métodos , Titanio , Dimensión Vertical
14.
J Biol Chem ; 276(46): 43361-73, 2001 Nov 16.
Artículo en Inglés | MEDLINE | ID: mdl-11524415

RESUMEN

Guanylyl cyclase-activating proteins are EF-hand Ca(2+)-binding proteins that belong to the calmodulin superfamily. They are involved in the regulation of photoreceptor membrane-associated guanylyl cyclases that produce cGMP, a second messenger of vertebrate vision. Here, we investigated changes in GCAP1 structure using mutagenesis, chemical modifications, and spectroscopic methods. Two Cys residues of GCAP1 situated in spatially distinct regions of the N-terminal domain (positions 18 and 29) and two Cys residues located within the C-terminal lobe (positions 106 and 125) were employed to detect conformational changes upon Ca(2+) binding. GCAP1 mutants with only a single Cys residue at each of these positions, modified with N,N'-dimethyl-N-(iodoacetyl)-N'-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)ethylenediamine, an environmentally sensitive fluorophore, and with (1-oxy-2,2,5,5-tetramethylpyrroline-3-methyl)methanethiosulfonate, a spin label reagent, were studied using fluorescence and EPR spectroscopy, respectively. Only minor structural changes around Cys(18), Cys(29), Cys(106), and Cys(125) were observed as a function of Ca(2+) concentration. No Ca(2+)-dependent oligomerization of GCAP1 was observed at physiologically relevant Ca(2+) concentrations, in contrast to the observation reported by others for GCAP2. Based on these results and previous studies, we propose a photoreceptor activation model that assumes changes within the flexible central helix upon Ca(2+) dissociation, causing relative reorientation of two structural domains containing a pair of EF-hand motifs and thus switching its partner, guanylyl cyclase, from an inactive (or low activity) to an active conformation.


Asunto(s)
Proteínas de Unión al Calcio/química , Proteínas de Unión al Calcio/metabolismo , Espectroscopía de Resonancia por Spin del Electrón/métodos , Secuencias de Aminoácidos , Secuencia de Aminoácidos , Animales , Calcio/química , Calcio/metabolismo , Calcio/farmacología , Bovinos , Cromatografía en Gel , Óxidos N-Cíclicos/farmacología , Cisteína/química , Relación Dosis-Respuesta a Droga , Motivos EF Hand , Electroforesis en Gel de Poliacrilamida , Activación Enzimática , Ojo/metabolismo , Colorantes Fluorescentes/farmacología , Guanilato Ciclasa/química , Proteínas Activadoras de la Guanilato-Ciclasa , Mesilatos/farmacología , Modelos Biológicos , Modelos Químicos , Modelos Moleculares , Datos de Secuencia Molecular , Mutagénesis Sitio-Dirigida , Mutación , Oxadiazoles/farmacología , Unión Proteica , Conformación Proteica , Estructura Terciaria de Proteína , Homología de Secuencia de Aminoácido , Espectrometría de Fluorescencia , Marcadores de Spin , Azufre/química
15.
J Biol Chem ; 276(2): 915-23, 2001 Jan 12.
Artículo en Inglés | MEDLINE | ID: mdl-11042171

RESUMEN

A novel regulator of G-protein signaling (RGS) has been isolated from a highly purified population of mouse long-term hematopoietic stem cells, and designated RGS18. It has 234 amino acids consisting of a central RGS box and short divergent NH(2) and COOH termini. The calculated molecular weight of RGS18 is 27,610 and the isoelectric point is 8.63. Mouse RGS18 is expressed from a single gene and shows tissue specific distribution. It is most highly expressed in bone marrow followed by fetal liver, spleen, and then lung. In bone marrow, RGS18 level is highest in long-term and short-term hematopoietic stem cells, and is decreased as they differentiate into more committed multiple progenitors. The human RGS18 ortholog has a tissue-specific expression pattern similar to that of mouse RGS18. Purified RGS18 interacts with the alpha subunit of both G(i) and G(q) subfamilies. The results of in vitro GTPase single-turnover assays using Galpha(i) indicated that RGS18 accelerates the intrinsic GTPase activity of Galpha(i). Transient overexpression of RGS18 attenuated inositol phosphates production via angiotensin receptor and transcriptional activation through cAMP-responsive element via M1 muscarinic receptor. This suggests RGS18 can act on G(q)-mediated signaling pathways in vivo.


Asunto(s)
Proteínas Portadoras/fisiología , Proteínas de Unión al GTP/fisiología , Células Madre Hematopoyéticas/fisiología , Péptidos y Proteínas de Señalización Intracelular , Transducción de Señal , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Proteínas Portadoras/química , Proteínas Portadoras/genética , Línea Celular , Clonación Molecular , GTP Fosfohidrolasas/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gi-Go/metabolismo , Subunidades alfa de la Proteína de Unión al GTP Gs/metabolismo , Variación Genética , Humanos , Ratones , Datos de Secuencia Molecular , Peso Molecular , Especificidad de Órganos , Proteínas RGS , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Transfección
16.
J Craniomaxillofac Surg ; 28(3): 176-80, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10964555

RESUMEN

The following report refers to a well described surgical procedure using a prototype vertical distractor developed in Cologne in cooperation with Martin Medizintechnik GmbH. The surgical technique has been refined by an L-shaped osteotomy stabilized posteriorly by a miniplate to limit the amount of callus regeneration in the molar region where no increase in vertical height is required. The surgical technique with its advantages and one complication is described as used in four patients undergoing six distraction treatments.


Asunto(s)
Aumento de la Cresta Alveolar/métodos , Mandíbula/cirugía , Osteogénesis por Distracción/instrumentación , Osteotomía/métodos , Adulto , Placas Óseas , Callo Óseo/crecimiento & desarrollo , Carcinoma de Células Escamosas/rehabilitación , Carcinoma de Células Escamosas/cirugía , Femenino , Humanos , Suelo de la Boca/cirugía , Neoplasias de la Boca/rehabilitación , Neoplasias de la Boca/cirugía
17.
Blood ; 96(3): 894-901, 2000 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-10910902

RESUMEN

Hematopoietic stem cell gene therapy holds promise for the treatment of many hematologic disorders. One major variable that has limited the overall success of gene therapy to date is the lack of sustained gene expression from viral vectors in transduced stem cell populations. To understand the basis for reduced gene expression at a single-cell level, we have used a murine retroviral vector, MFG, that expresses the green fluorescent protein (GFP) to transduce purified populations of long-term self-renewing hematopoietic stem cells (LT-HSC) isolated using the fluorescence-activated cell sorter. Limiting dilution reconstitution of lethally irradiated recipient mice with 100% transduced, GFP(+) LT-HSC showed that silencing of gene expression occurred rapidly in most integration events at the LT-HSC level, irrespective of the initial levels of GFP expression. When inactivation occurred at the LT-HSC level, there was no GFP expression in any hematopoietic lineage clonally derived from silenced LT-HSC. Inactivation downstream of LT-HSC that stably expressed GFP( )in long-term reconstituted animals was restricted primarily to lymphoid cells. These observations suggest at least 2 distinct mechanisms of silencing retrovirally expressed genes in hematopoietic cells.


Asunto(s)
Técnicas de Transferencia de Gen , Terapia Genética , Vectores Genéticos , Trasplante de Células Madre Hematopoyéticas , Células Madre Hematopoyéticas/virología , Retroviridae , Animales , Diferenciación Celular/genética , Expresión Génica , Proteínas Fluorescentes Verdes , Células Madre Hematopoyéticas/citología , Células Madre Hematopoyéticas/fisiología , Humanos , Proteínas Luminiscentes , Ratones , Factores de Tiempo
18.
Arch Otolaryngol Head Neck Surg ; 125(4): 433-7, 1999 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10208681

RESUMEN

OBJECTIVES: To shed light on the endoscopic anatomy of the middle ear seen on 2-port endoscopy and to describe potential clinical applications. DESIGN: Anatomical structures were visualized by transmeatal or transtympanic rigid scopes of different angles and by a flexible scope in the eustachian tube. This arrangement ensured reciprocal guidance of the scopes and provided access to regions not seen otherwise. SETTING: The Department of Anatomy 1, University of Vienna, Vienna, Austria. MATERIALS: Forty tympanic cavities obtained from cadaver skulls without prior fixation were examined. Specimens did not show any abnormalities and were chosen without regard to age or sex. RESULTS: Depending on the angle of view, rigid transmeatal or transtympanic endoscopes provided a full view of the entire tympanic cavity except for the epitympanum, access to which was barred by the incudomallear joint, the mallear folds, and the tympanic chord, but the epitympanum was well visualized through the flexible, steerable, transtubal scope. CONCLUSIONS: Two-port endoscopy of the middle ear offers a full view of all structures in the tympanic cavity. The atraumatic transtubal approach to the tympanic cavity enhances the safety of transmeatal interventions and facilitates postoperative follow-up.


Asunto(s)
Oído Medio/anatomía & histología , Endoscopía/métodos , Cadáver , Femenino , Humanos , Masculino
20.
Biochemistry ; 37(25): 9016-23, 1998 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-9636045

RESUMEN

A mutant of the ferric enterobactin receptor, FepA, containing a valine to cysteine (V338C) substitution was made and the purified protein selectively modified with a sulfhydryl-specific nitroxide spin label. In reconstituted liposomes, interaction of the attached spin label with a combination of water-soluble and lipid-soluble relaxation agents indicated that the V338C site was located in the polar headgroup region of the membrane, approximately 1.5-4.5 A above the phosphate groups of the lipids. Binding of the ligand, ferric enterobactin (FeEnt), to the purified spin-labeled protein produced a significant decrease in both the rotational freedom and accessibility of the nitroxide, indicating the formation of new structural contacts between the spin label and either the protein or the bound ligand. Electron spin-echo (ESE) measurements of the nitroxide phase-memory relaxation rate in the presence and absence of bound ligand showed substantial dipolar coupling between the Fe3+ of FeEnt and the spin label and provided an iron-nitroxide distance estimate in the range of 20-30 A. We conclude that the ligand-induced changes in spin label motion and accessibility are due to new tertiary contacts with the protein and not to direct contact with the ligand. These studies suggest that V338C may occupy a hinge region connecting the ligand binding surface loop to the beta-barrel and provide the strongest evidence to date of an in vitro ligand-induced conformational change in FepA.


Asunto(s)
Proteínas de la Membrana Bacteriana Externa , Proteínas Portadoras/química , Enterobactina/metabolismo , Conformación Proteica , Receptores de Superficie Celular , Proteínas Portadoras/genética , Cisteína/genética , Espectroscopía de Resonancia por Spin del Electrón/métodos , Ligandos , Membrana Dobles de Lípidos/química , Membrana Dobles de Lípidos/metabolismo , Liposomas , Mutagénesis Sitio-Dirigida , Marcadores de Spin , Valina/genética
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