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1.
Gynecol Oncol ; 149(2): 297-300, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29534832

RESUMEN

OBJECTIVES: Low grade endometrial stromal sarcoma (LG-ESS) is a rare cancer with an indolent course. We aimed to assess the effectiveness of adjuvant hormonal suppression (HT) with or without oophorectomy (BSO) in prolonging progression free survival (PFS) and overall survival (OS) in patients with LG-ESS. METHODS: We performed a multi-institutional retrospective review of patients treated for low grade LG-ESS from 1985 to 2014. Demographics, treatment and recurrence data were abstracted from medical records. Pathologic diagnosis was confirmed by a gynecologic pathologist. Long-term patient-reported outcomes were obtained via mailed survey. RESULTS: One-hundred-twelve patients underwent surgery for LG-ESS; 59 had postoperative data with a median follow-up of 55months (1-325months). The mean age at diagnosis was 48.5years (22-82years). Forty-nine (61%) had stage I disease. The most common presenting symptoms were abnormal uterine bleeding (38%) and pelvic mass (17%). Seventy-one (63%) patients had BSO at the time of diagnosis. Of the 59 patients with postoperative follow-up information, 49 (73%) underwent BSO, 26 (44%) received HT, 20 (33%) were expectantly managed, and 6 (10%) received chemotherapy, radiation or both. Median PFS for the entire group was 53months and OS was 63months. PFS for those who underwent BSO compared with those who retained their ovaries was 38 vs 11months, p=0.071. PFS for HT vs no HT was 28 vs 23months, p=0.77. CONCLUSIONS: Consistent with prior series, our results support BSO to prolong PFS in LG-ESS but are limited by sample size. Larger studies with more complete follow-up are needed to determine the effect of adjuvant hormonal suppression.


Asunto(s)
Neoplasias Endometriales/tratamiento farmacológico , Neoplasias Endometriales/cirugía , Sarcoma Estromático Endometrial/tratamiento farmacológico , Sarcoma Estromático Endometrial/cirugía , Adulto , Anciano , Anciano de 80 o más Años , Inhibidores de la Aromatasa/administración & dosificación , Supervivencia sin Enfermedad , Neoplasias Endometriales/patología , Femenino , Hormona Liberadora de Gonadotropina/agonistas , Humanos , Persona de Mediana Edad , Clasificación del Tumor , Progestinas/administración & dosificación , Estudios Retrospectivos , Salpingooforectomía , Sarcoma Estromático Endometrial/patología , Resultado del Tratamiento , Adulto Joven
2.
J Oral Rehabil ; 45(7): 504-511, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29761534

RESUMEN

The objective of this study was to analyse the co-contraction behaviour of jaw and neck muscles during force-controlled experimental grinding in the supine position. Twelve symptom-free subjects were enrolled in the experimental study. Electromyographic (EMG) activity of semispinalis capitis, splenius capitis and levator scapulae muscles was recorded bilaterally with intramuscular fine-wire electrodes, whereas that of sternocleidomastoideus, infrahyoidal, suprahyoidal, masseter and anterior temporalis muscles were registered with surface electrodes. EMG and force measurements were performed during tasks simulating tooth grinding on custom-made intraoral metal splints. The mean EMG activity normalised by maximum voluntary contraction (% MVC) of each of the neck muscles studied during grinding was analysed and compared with previous data from jaw clenching at identical force (100 N) and (supine) position. The occurrence of low-level, long-lasting tonic activation (LLTA) of motor units was also documented. The mean three-dimensional force vector of the grinding forces was 106 ± 74 N. In the frontal plane, the incline to the midsagittal plane ranged between 10° and 15°. In the midsagittal plane, the incline to the frontal plane was negligibly small. Posterior neck muscle activity during grinding ranged between 4.5% and 12% MVC and during clenching with 100 N between 1.8% and 9.9% MVC. Masticatory muscle activity during grinding ranged between 17% and 21% MVC for contralateral masseter and ipsilateral temporalis and between 4% and 6.5% for ipsilateral masseter and contralateral temporalis. LLTA had an average duration of 195 ± 10 seconds. The findings from this study do not support pathophysiological muscle chain theories postulating simple biomechanical coupling of neck and jaw muscles. Co-contractions of neck and masticatory muscles may instead occur as a result of complex neurophysiological interactions.


Asunto(s)
Bruxismo/fisiopatología , Electromiografía , Masticación/fisiología , Músculos Masticadores/fisiopatología , Contracción Muscular/fisiología , Músculos del Cuello/fisiología , Adulto , Fuerza de la Mordida , Femenino , Humanos , Masculino , Posición Supina/fisiología
3.
J Oral Rehabil ; 45(9): 669-676, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29855069

RESUMEN

This study was to compare the short-term therapeutic efficacy of device-supported sensorimotor training with that of standard splint therapy for patients with myofascial temporomandibular disorder (TMD) pain over a treatment period of 3 months. We tested the hypothesis that both types of intervention are equally effective for pain reduction. In addition, the electromyographic (EMG) activity of the temporal and masseter muscles was recorded under conditions of force-controlled submaximum and maximum biting in intercuspation. Of consecutive patients seeking treatment for non-odontogenic oro-facial pain, 45 patients with myofascial TMD pain (graded chronic pain status, GCPS, I and II) were randomly assigned to 2 treatment groups (sensorimotor training and conventional splint treatment). Patients were evaluated 4 times (initial examination, 2, 6 and 12 weeks later) by use of the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD). Electromyographic activity was recorded at the initial session and after 3 months. Ease-of-use of the treatment options was also evaluated. Significant (P < .0001) pain reduction (sensorimotor training 53%, splint therapy 40%) was achieved for both groups, with no significant differences (P > .05) between the groups. Force-controlled sub-maximum normalized electromyographic activity was significantly different between T0 and T3 for group A (sensorimotor training, P < .05) but was not significantly different for group B (splint, P > .05). For normalized maximum-biting EMG activity in intercuspation, however, a significant increase in EMG activity was observed for group A for the masseter and temporal muscles (P < .001) and for group B for the masseter muscle only (P < .001). Moreover, sensorimotor training was significantly (P < .05) less easy to use than the splint. The results of this study confirm the pain-reducing effect of sensorimotor training for patients with myofascial TMD pain (GCPS I and II). This innovative active treatment might be a promising option for TMD pain patients.


Asunto(s)
Electromiografía , Dolor Facial/fisiopatología , Músculos Masticadores/fisiopatología , Trastornos de la Articulación Temporomandibular/fisiopatología , Adulto , Análisis de Varianza , Fuerza de la Mordida , Dolor Facial/rehabilitación , Dolor Facial/terapia , Femenino , Humanos , Registro de la Relación Maxilomandibular , Masculino , Contracción Muscular , Ferulas Oclusales , Dimensión del Dolor , Trastornos de la Articulación Temporomandibular/rehabilitación , Trastornos de la Articulación Temporomandibular/terapia , Resultado del Tratamiento , Adulto Joven
4.
J Oral Rehabil ; 43(4): 259-68, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26707515

RESUMEN

Strategies for recruitment of masseter muscle motor units (MUs), provoked by constant bite force, for different vertical jaw relations have not previously been investigated. The objective of this study was to analyse the effect of small changes in vertical jaw relation on MU recruitment behaviour in different regions of the masseter during feedback-controlled submaximum biting tasks. Twenty healthy subjects (mean age: 24·6 ± 2·4 years) were involved in the investigation. Intra-muscular electromyographic (EMG) activity of the right masseter was recorded in different regions of the muscle. MUs were identified by the use of decomposition software, and root-mean-square (RMS) values were calculated for each experimental condition. Six hundred and eleven decomposed MUs with significantly (P < 0·001) different jaw relation-specific recruitment behaviour were organised into localised MU task groups. MUs with different task specificity in seven examined tasks were observed. The RMS EMG values obtained from the different recording sites were also significantly (P < 0·01) different between tasks. Overall MU recruitment was significantly (P < 0·05) greater in the deep masseter than in the superficial muscle. The number of recruited MUs and the RMS EMG values decreased significantly (P < 0·01) with increasing jaw separation. This investigation revealed differential MU recruitment behaviour in discrete subvolumes of the masseter in response to small changes in vertical jaw relations. These fine-motor skills might be responsible for its excellent functional adaptability and might also explain the successful management of temporomandibular disorder patients by somatic intervention, in particular by the use of oral splints.


Asunto(s)
Electromiografía , Músculo Masetero/fisiología , Contracción Muscular/fisiología , Reclutamiento Neurofisiológico/fisiología , Análisis de Varianza , Fuerza de la Mordida , Oclusión Dental , Femenino , Voluntarios Sanos , Humanos , Masculino , Músculo Masetero/diagnóstico por imagen , Adulto Joven
5.
J Oral Rehabil ; 41(7): 477-85, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24712837

RESUMEN

Localised motor-unit (MU) recruitment in the masseter was analysed in this study. We investigated whether differential activation behaviour, which has already been reported for distant masseter regions, can also be detected in small muscle subvolumes at the level of single MUs. Two bipolar fine-wire electrodes and an intra-oral 3D bite-force transmitter were used to record intra-muscular electromyograms (EMG) resulting from controlled bite-forces of 10 healthy human subjects (mean age 24.1 ± 1.2 years). Two-hundred and seventeen decomposed MUs were organised into localised MU task groups with different (P < 0.001) force-direction-specific behaviour. Proportions of MUs involved in one, two, three or four examined tasks were 46%, 31%, 18% and 5%, respectively. This study provides evidence of the ability of the neuromuscular system to modify the mechanical output of small masseter subvolumes by differential control of adjacent MUs belonging to distinct task groups. Localised differential activation behaviour of the masseter may be the crucial factor enabling highly flexible and efficient adjustment of the muscle activity in response to complex local biomechanical needs, for example, continually varying bite-forces during the demanding masticatory process.


Asunto(s)
Músculo Masetero/fisiología , Contracción Muscular/fisiología , Reclutamiento Neurofisiológico/fisiología , Adulto , Fuerza de la Mordida , Electrodos , Electromiografía/métodos , Femenino , Humanos , Masculino , Adulto Joven
6.
J Oral Rehabil ; 41(5): 346-52, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24843864

RESUMEN

Immediate adaptation to experimental-balancing interferences is known to affect jaw kinematics and electromyographic activity (EMG). However, little is known about the influence on masticatory performance parameters. This study hypothesises that balancing-side interferences significantly reduce the performance of the masticatory system. Twenty-one healthy subjects (eleven female, mean age: 24.1 ± 1.2 years) chewed standardised silicone cubes performing 15 masticatory cycles on the right side under three experimental conditions: (i) natural dentition (ND), (ii) splints with structured occlusal profiles (SS) (iii) splints with balancing interferences in the left molar region (OI). The particle size distribution was determined by a validated scanning procedure and curve fitted with the Rosin-Rammler function to determine X(50)-values. The EMG of both temporalis and masseter muscles was recorded simultaneously, and the total muscle work (TMW) was calculated. A jaw-tracking device recorded the incisal movement path (IMP). The functional parameters under the experimental conditions were compared by repeated-measures analysis of variance. The findings confirm our hypothesis. The X(50)-values differed significantly (P < 0.01) between ND and OI (4.34 vs. 4.60 mm), and between SS and OI (4.34 vs. 4.60 mm), respectively. In contrast, no significant differences (P > 0.05) were observed between SS and ND. There was no significant difference in both TMW (1269.0 vs. 1284.9 vs. 1193.9 µV*s) and IMP (720.2 vs. 735.3 vs. 723.1 mm) amongst the three conditions (P > 0.05). These findings confirm the assumption that the disturbance of the habitual chewing cycles by balancing-side interferences significantly reduces the masticatory performance in the short term. Occlusal balancing-side interferences are common technical failures of dental restorations. Simulation of this condition caused deterioration of masticatory performance in healthy young adults. Further studies should be carried out, on whether the observed effect is long-term and whether masticatory performance decreases even more in patients with reduced adaptive capacity.


Asunto(s)
Electromiografía , Mandíbula/fisiología , Músculo Masetero/fisiología , Masticación/fisiología , Movimiento/fisiología , Músculo Temporal/fisiología , Adulto , Fenómenos Biomecánicos , Oclusión Dental , Femenino , Humanos , Masculino , Ferulas Oclusales , Rango del Movimiento Articular
7.
Clin Oral Investig ; 17(1): 259-67, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22302454

RESUMEN

OBJECTIVES: A key aspect of complex restorative therapy is reconstruction of a new three-dimensional jaw relation. The objective of this study was to test the hypotheses that the initially recorded jaw relation would deviate substantially from the jaw position of the prosthetic reconstruction and that activity ratios of the jaw muscles would be significantly different for each of these jaw positions. MATERIALS AND METHODS: In 41 healthy subjects, 41 examiners incorporated intraoral occlusal devices fabricated with all the technical details and procedures commonly used during prosthetic reconstructions. The jaw positions in centric relation with the incorporated occlusal devices were telemetrically measured in the condylar, first molar and incisal regions, relative to intercuspation. Electromyographic (EMG) activity of the temporalis and masseter muscles was recorded, and activity ratios were calculated for homonymous and heteronymous muscles. RESULTS: The recorded jaw relation differed significantly (p < 0.001) from the jaw position reconstructed with the intraoral occlusal devices. The initially recorded jaw relation was reproduced with the intraoral occlusal device with spatial accuracy of approximately 0.3 mm in the condylar, molar and incisal regions. The EMG ratios between centric relations and the reconstructed positions were significantly different (p < 0.05) for the temporal muscle and the temporalis/masseter ratio. CONCLUSIONS: The findings revealed that three-dimensional jaw-relation recording may be reproduced in a simulated prosthetic reconstruction within the accuracy reported for replicate intraoral bite recordings. CLINICAL RELEVANCE: Centric relation recordings may be reproduced in a prosthetic reconstruction with the spatial accuracy of 0.3 mm.


Asunto(s)
Diseño de Prótesis Dental , Registro de la Relación Maxilomandibular/métodos , Resinas Acrílicas/química , Relación Céntrica , Articuladores Dentales , Materiales de Impresión Dental/química , Oclusión Dental Céntrica , Electromiografía , Femenino , Humanos , Imagenología Tridimensional/métodos , Incisivo/anatomía & histología , Registro de la Relación Maxilomandibular/instrumentación , Masculino , Mandíbula/anatomía & histología , Cóndilo Mandibular/anatomía & histología , Músculo Masetero/fisiología , Metilmetacrilatos/química , Modelos Dentales , Diente Molar/anatomía & histología , Contracción Muscular/fisiología , Telemetría/instrumentación , Músculo Temporal/fisiología , Interfaz Usuario-Computador , Adulto Joven
8.
J Oral Rehabil ; 39(5): 338-48, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-22220913

RESUMEN

Aim of this study was to introduce a feasible and valid technique for the assessment of masticatory performance that is comparable to the standard sieving method. Twenty-one chewing samples (Optosil) comminuted by healthy dentate adults were analysed with a sieving and scanning method. Scanning was performed using a conventional flatbed scanner (1200dpi). All scanned images underwent image analysis (ImageJ), which yielded descriptive parameters such as area, best-fitting ellipse for each particle. Of the 2D-image, a volume was estimated for each particle, which was converted into a weight. To receive a discrete distribution of particle sizes comparable to sieving, five chewing samples were used to calculate a size-dependent area-volume-conversion factor. The sieving procedure was carried out with a stack of 10 sieves, and the retained particles per sieve were weighed. The cumulated weights yielded by either method were curve-fitted with the Rosin-Rammler distribution to determine the median particle size x(50) . The Rosin-Rammler distributions for sieving and scanning resemble each other. The distributions show a high correlation (0·919-1·0, n= 21, P<0·01, Pearson's correlation coefficient). The median particle sizes vary between 3·83 and 4·77mm (mean: 4·31) for scanning and 3·53 and 4·55mm (mean: 4·21) for sieving. On average, scanning overestimates the x(50) values by 2·4%. A modified Bland-Altman plot reveals that 95% of the x(50) values fall within 10% of the average x(50) . The scanning method is a valid, simple and feasible method to determine masticatory performance.


Asunto(s)
Masticación/fisiología , Tamaño de la Partícula , Adulto , Estudios de Factibilidad , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Óptica y Fotónica , Reproducibilidad de los Resultados , Siliconas , Adulto Joven
9.
J Oral Rehabil ; 38(10): 729-36, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21385200

RESUMEN

Alterations of body sway caused by isometric contractions of the jaw muscles have been reported previously. The objective of this study was to test if motor tasks of the masticatory system with different control demands affect body posture differently during quiet stance. Position and sway displacements of the center of foot pressure (COP) were measured for 20 healthy subjects who either kept the mandible at rest or performed unilateral and bilateral maximum voluntary teeth clenching, feedback-controlled biting tasks at submaximum bite forces, or unilateral chewing. Two weeks later the measurements were repeated. Compared with quiet stance, the COP results revealed significant changes during the feedback-controlled biting tasks. Robust sway reduction and anterior displacement of the COP were observed under these conditions. Body oscillations were not significantly affected by maximum bites or by unilateral chewing. For most of the variables investigated there were no significant differences between unilateral and bilateral biting. Robust sway reduction during feedback-controlled biting tasks in healthy subjects involved a stiffening phenomenon that was attributed to the common physiological repertoire of posture control, and might optimize the stability of posture under these conditions.


Asunto(s)
Contracción Isométrica/fisiología , Maxilares/fisiología , Equilibrio Postural/fisiología , Desempeño Psicomotor/fisiología , Adulto , Fuerza de la Mordida , Electromiografía , Femenino , Humanos , Masculino , Valores de Referencia
10.
J Oral Rehabil ; 38(12): 912-20, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21569075

RESUMEN

Neuromuscular adaptations during skill acquisition have been extensively investigated for skeletal muscles. Motor rehabilitation is the main target for application of motor training. Such measures are also relevant for the musculature of the jaw, but few data are available for motor adaptation of the masticatory system. The objective of this study was to evaluate and compare long-term training effects of different motor tasks on masseter and temporal muscles. In 20 healthy subjects, the electromyographic response to unilateral and bilateral maximum voluntary tooth clenching, balancing the mandible on a hydrostatic system under force-feedback-controlled conditions, and unilateral chewing was investigated in an initial session and then in two follow-up sessions separated by 2 and 10 weeks from baseline. Motor tasks were repeated three times for chewing, nine times for maximum biting (MB) and 24 times for the coordination tasks (CT). The sequences of the various motor tasks were applied once in the first session and twice in the second and third sessions. No effects of training were observed for MB tasks except for MB in intercuspation, for which significant yet transient avoidance behaviour occurred in the second session. No significant effects were found for chewing tests. For the CT, however, a robust significant long-term training effect was detected which reduced the electric muscle activity in session 2 by approximately 20% and in session 3 by approximately 40% compared with the initial measurements. The study showed that the masticatory muscles are remarkably prone to motor adaptation if demanding CT must be accomplished.


Asunto(s)
Fuerza de la Mordida , Electromiografía , Ejercicio Físico/fisiología , Masticación/fisiología , Contracción Muscular/fisiología , Femenino , Humanos , Masculino , Resultado del Tratamiento , Adulto Joven
11.
Eur J Dent Educ ; 15(3): 172-8, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21762322

RESUMEN

INTRODUCTION: An objective structured clinical examination (OSCE) has been implemented in preclinical dentistry. It was taken at an early stage (propaedeutics course). The objectives of this study were to evaluate the reliability, validity, and feasibility of the examination, and the effect of circuit number on OSCE score. METHODS: The OSCE was designed by an expert committee on the basis of pre-reviewed blueprints and checklists. Eleven stations formed an interdisciplinary circuit. Six groups of students (n = 62) passed sequentially round the same circuit. Statistical analysis was performed by using SPSS. Reliability was determined by measurement of internal consistency (Cronbach's α, Guttman's λ(2) ), standard error of measurement (SEM) (comprising generalisability index α, dependability index ϕ and pass 150;fail reliability p(c) ), consistency coefficient κ, item 150;scale correlation (Pearson correlation), and, because the unidimensionality of the stations could not be assumed, factor analysis including varimax rotation. Convergent validity (Pearson correlation, t-test), and predictive validity for future preclinical courses and the final preclinical examination were assessed by analysis of variance (ANOVA). The effect of the circuit number on score improvement was calculated, including a correction for the general competence of the students (ANOVA). Cost was calculated on the basis of the time invested. RESULTS: Fifty-three out of sixty-two students passed the OSCE (mean score: 67%, SD 7.7, range, 47-81). Scores for each station correlated significantly with total scores (r = 0.35-0.54, P < 0.01). For internal consistency, α = 0.75 (relative SEM 3.8) and λ(2) = 0.766. The dependability index was ϕ = 0.694 (absolute SEM 4.4), p(c) = 0.89 and κ = 0.61. Factor analysis yielded two components: dental-materials-oriented stations and all other stations (explained variance 43%). Scores correlated significantly with success in passing practical tests (i.e. performing dental procedures under examination conditions) (known group validity, P < 0.01) and with scores for subsequent courses and the final preclinical examination (Physikum) (predictive validity, P < 0.001). Later groups performed 4% better on average (CI 95%: 1.2-6.8%; P < 0.01). The cost was 181 Euro per student. CONCLUSIONS: The OSCE is reliable and valid in the context of preclinical dentistry. The cost is substantial. The problem of improvement of students' results with ascending circuit number has to be addressed.


Asunto(s)
Educación en Odontología , Evaluación Educacional/métodos , Análisis de Varianza , Costos y Análisis de Costo , Curriculum , Evaluación Educacional/economía , Evaluación Educacional/normas , Estudios de Factibilidad , Humanos , Reproducibilidad de los Resultados , Estadísticas no Paramétricas
12.
Int J Prosthodont ; 34(4): 441­447, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33651041

RESUMEN

PURPOSE: To assess the impact of different types of dental prostheses, including definitive and interim restorations, on oral health-related quality of life (OHRQoL) before and after prosthetic treatment. MATERIALS AND METHODS: A total of 151 patients received prosthetic treatment at one of two German departments of prosthetic dentistry. The patients' OHRQoL was assessed using the German version of the Oral Health Impact Profile (OHIP-G53) at baseline (T0) and at 1 week (T1) and 3 months (T2) after treatment. Patients were divided into 10 subgroups according to their pre- and posttreatment status. The effect of the type (no prosthesis; fixed prosthesis; removable prosthesis) and duration of wear (definitive; interim) of the restorations was evaluated. Results were analyzed using Kolmogorov-Smirnov, Kruskal-Wallis, and Mann-Whitney U tests with a significance level of P = .05. RESULTS: The highest OHRQoL was recorded for patients with fixed restorations, as indicated by the fact that their OHIP scores were lowest. A significant improvement in OHRQoL (P ≤ .034) was observed for patients who needed prostheses and were then treated with removable or fixed restorations. The OHIP score was affected by a change in restoration type. Rehabilitation with definitive prostheses had a significant effect on posttreatment OHRQoL (P ≤ .006). CONCLUSION: In general, prosthetic rehabilitation by use of fixed or removable prostheses resulted in an improvement in OHRQoL. The use of the same type of restoration before and after treatment had a positive effect on OHRQoL. If possible, a change of restoration type should be avoided. For patients who require permanent prostheses, the use of fixed and removable restorations is recommended. For oral rehabilitation, fixed restorations should be preferred in order to achieve best possible improvement of OHIP score.


Asunto(s)
Salud Bucal , Calidad de Vida , Prótesis Dental de Soporte Implantado , Humanos , Estudios Prospectivos , Encuestas y Cuestionarios
13.
Clin Neurophysiol ; 127(9): 3198-3204, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27298232

RESUMEN

OBJECTIVE: To study motor unit activity in the medio-lateral extension of the masseter using an adapted scanning EMG technique that allows studying the territories of multiple motor units (MUs) in one scan. METHODS: We studied the m. masseter of 10 healthy volunteers in whom two scans were performed. A monopolar scanning needle and two pairs of fine-wire electrodes were inserted into the belly of the muscle. The signals of the fine wire electrodes were decomposed into the contribution of single MUs and used as a trigger for the scanning needle. In this manner multiple MU territory scans were obtained simultaneously. RESULTS: We determined 161 MU territories. The maximum number of territories obtained in one scan was 15. The median territory size was 4.0mm. Larger and smaller MU territories were found throughout the muscle. CONCLUSIONS: The presented technique showed its feasibility in obtaining multiple MU territories in one scan. MUs were active throughout the depth of the muscle. SIGNIFICANCE: The distribution of electrical and anatomical size of MUs substantiates the heterogeneous distribution of MUs throughout the muscle volume. This distributed activity may be of functional significance for the stabilization of the muscle during force generation.


Asunto(s)
Electromiografía/métodos , Músculo Masetero/fisiología , Contracción Muscular/fisiología , Reclutamiento Neurofisiológico/fisiología , Adulto , Femenino , Humanos , Masculino
14.
Clin Cancer Res ; 6(2): 585-96, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10690543

RESUMEN

DNA aneuploidy characterizes a proportion of malignant bone marrow (BM)-localized plasma cells in multiple myeloma (MM). This analysis shows that for most MM patients, circulating clonotypic B cells in MM are also hyperdiploid. Although all normal B cells and some malignant B cells are diploid, hyperdiploidy is likely to be exclusive to those that are malignant. Hyperdiploid MM B cells express CD34 and have clonotypic IgH transcripts, confirming them as part of the malignant clone. For MM, 92% (70/76) of patients had a DNA hyperdiploid subset [5-30% of peripheral blood mononuclear cells (PBMCs)] of CD19+ B cells. All CD19+ PBMCs in MM expressed CD19 and IgH variable diversity joining (VDJ) transcripts, confirming them as B cells. DNA aneuploid cells were undetectable in T or B lymphocytes from normal blood, spleen or thymus, or in blood from patients with B chronic lymphocytic leukemia. In MM, untreated patients had the highest DNA index (1.12). DNA hyperdiploid PBMCs were most frequent among untreated patients and were significantly reduced after chemotherapy. Diploid B cells were significantly more frequent after chemotherapy than at diagnosis. Of the hyperdiploid PBMCs, 81 +/- 3% expressed CD34 and CD19. In contrast to circulating CD34+ B cells, CD34- B cells in MM are diploid. In MM, unlike hyperdiploid PBMC B cells, hyperdiploid BM plasma cells lack both CD34 and CD19, suggesting that loss of CD34 correlates with differentiation and BM anchoring. In situ reverse transcription-PCR of the CD34+ (hyperdiploid) and CD34- (diploid) PBMC B-cell subsets was performed using patient-specific primers to amplify clonotypic IgH VDJ transcripts. Confirming previous work, CD34+ hyperdiploid MM PBMCs were clonotypic (86 +/- 5%). In contrast, CD34- diploid MM PBMCs had few monoclonal cells (4.8 +/- 2%). The lack of hyperdiploidy, together with the relative absence of cells having clonotypic transcripts, suggests these polyclonal CD34- B cells are normal. After culture in colchicine to arrest mitosis, hyperdiploid B cells were reduced and MM B cells accumulated in a diploid G2-M, suggesting that hyperdiploid in MM may represent a transient S-phase arrest rather than an aneuploid G0 phase. The DNA hyperdiploidy of CD34+ clonotypic B cells suggests these cells may be clinically important constituents of the myeloma clone and that they may play a direct role in the spread of myeloma.


Asunto(s)
Linfocitos B/inmunología , Reordenamiento Génico , Genes de Inmunoglobulinas , Cadenas Pesadas de Inmunoglobulina/genética , Mieloma Múltiple/genética , Mieloma Múltiple/inmunología , Células de la Médula Ósea/inmunología , Células de la Médula Ósea/patología , Diploidia , Humanos , Leucemia Linfocítica Crónica de Células B/sangre , Leucemia Linfocítica Crónica de Células B/genética , Leucemia Linfocítica Crónica de Células B/inmunología , Leucemia Linfocítica Crónica de Células B/patología , Mieloma Múltiple/sangre , Mieloma Múltiple/patología , Pronóstico , Linfocitos T/inmunología , Transcripción Genética
15.
J Leukoc Biol ; 64(6): 781-90, 1998 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-9850161

RESUMEN

During human thymic differentiation, interactions between fibronectin (Fn)/beta1 integrins and hyaluronan (HA)/RHAMM control motility and Fn/beta1 integrins mediate spontaneous Fn-dependent adhesion. Multinegative (MN, CD3-4-8-) thymocytes exhibit strong spontaneous adherence to Fn (75%) that was efficiently inhibited by anti-alpha5beta1 and only weakly inhibited by anti-alpha4beta1. The relatively weak adherence of unfractionated thymocytes to Fn required both alpha4beta1 and alpha5beta1. Video time-lapse microscopy indicates that a subset of thymocytes also undergo spontaneous Fn-dependent motility mediated by alpha5beta1, alpha4beta1, and the HA-receptor RHAMM, but not by CD44. The loss of motility after hyaluronidase treatment of thymocytes indicated that motility is strongly dependent on HA. Of motile cells, 55% were DP, 19% were DN, and 24% were CD4+SP, but only 1% were CD8+SP. Overall, for MN thymocytes, beta1 integrin mediated Fn-adhesion, but after expression of CD4/CD8, beta1 integrins mediated Fn-dependent motility. Treatment with the activating anti-beta1 mAb QE.2E5 inhibited thymic motility and converted otherwise nonadherent thymocytes to an adherent state. High-avidity interactions via integrins appear to supercede the motogenicity of RHAMM and HA, suggesting that integrin avidity may regulate RHAMM. During thymic development, changes in adhesion or motility appear to be mediated by integrin avidity modulation.


Asunto(s)
Movimiento Celular/fisiología , Proteínas de la Matriz Extracelular/fisiología , Receptores de Hialuranos/fisiología , Ácido Hialurónico/fisiología , Integrina beta1/fisiología , Timo/crecimiento & desarrollo , Adulto , Anticuerpos Bloqueadores/farmacología , Adhesión Celular/fisiología , Diferenciación Celular , Niño , Preescolar , Humanos , Lactante , Recién Nacido , Integrina alfa4beta1 , Integrinas/biosíntesis , Receptores de Fibronectina/biosíntesis , Receptores de Fibronectina/inmunología , Receptores Mensajeros de Linfocitos/biosíntesis , Células Madre/fisiología , Subgrupos de Linfocitos T/metabolismo , Subgrupos de Linfocitos T/fisiología , Timo/citología
16.
Am J Hypertens ; 14(7 Pt 1): 632-6, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11465646

RESUMEN

The aim of this study was to investigate the hypothesis that the expression of certain HLA antigens may constitute a risk marker for cardiovascular hypertrophy in subjects with arterial hypertension. We examined 158 subjects with newly diagnosed arterial hypertension. HLA class I (-A, -B, -Cw) and class II (-DR, -DQ) antigens were studied by two-step microlymphocytotoxic technique in peripheral T and B lymphocytes. Carotid intima-media thickness (IMT) was determined noninvasively by ultrasonography. The left ventricular mass was calculated according to the formula of Devereux and was normalized by the individual's height (LVM/h). The individuals with DR13 and DR17 were characterized by higher values of IMT compared to those without these HLA (0.096+/-0.018 cm v 0.085+/-0.021 cm, P = .011, 0.100+/-0.019 cm v 0.084+/-0.021 cm, P = .012, respectively). The presence of HLA DQ7 was characterized by markedly higher values of IMT that just failed to reach statistical significance (0.091+/-0.019 cm v 0.084+/-0.022 cm, P = .045). Furthermore, subjects with HLA DQ7 and DR11 exhibited higher values of LVM/h in comparison to those without these HLA (191.3+/-36.2 g/m v 166.9+/-41.0 g/m, P = .029 and 194.6+/-34.3 g/m v 166.6+/-40.9 g/m, P = .034, respectively). Hypertensive subjects with HLA B51 tended to have lower LVM/h (166.6+/-39.0 g/m with v 176.0+/-41.7 g/m without HLA B51, P = .045). In conclusion, it can be postulated that certain HLA phenotypes exhibit an association with increased carotid IMT and left ventricular mass in hypertensive subjects. The determination of these antigens may help to identify subjects at high risk for cardiovascular events.


Asunto(s)
Arterias Carótidas/patología , Prueba de Histocompatibilidad , Hipertensión/genética , Hipertensión/patología , Miocardio/patología , Adulto , Presión Sanguínea , Enfermedades de las Arterias Carótidas/diagnóstico por imagen , Enfermedades de las Arterias Carótidas/epidemiología , Enfermedades de las Arterias Carótidas/patología , Femenino , Predisposición Genética a la Enfermedad , Humanos , Hipertensión/epidemiología , Hipertrofia Ventricular Izquierda/diagnóstico por imagen , Hipertrofia Ventricular Izquierda/epidemiología , Hipertrofia Ventricular Izquierda/patología , Masculino , Persona de Mediana Edad , Fenotipo , Factores de Riesgo , Túnica Íntima/patología , Ultrasonografía
17.
Int Angiol ; 21(1): 63-9, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11941276

RESUMEN

BACKGROUND: The aim of the present study was to investigate the association of the angiotensin-converting enzyme (ACE) insertion/deletion (I/D) polymorphism with the ultrasonographically evaluated severity and characteristics of carotid artery atherosclerosis in subjects with diabetes mellitus type 2. METHODS: We assessed 184 subjects with diabetes mellitus type 2, 75 males and 109 females, mean age 61.4+/-7.7 years. All subjects were receiving oral antidiabetic drugs for glycemic control and were free of cardiovascular events. The ACE genotype was analyzed by the polymerase chain reaction (PCR) technique. The ultrasonographic examination of the carotid arteries was performed in both B-mode imaging and Doppler ultrasound. The common carotid artery intima-media thickness was assessed 15-20 mm proximal to the dilatation of the carotid bulb. The atheromatous lesions were classified according to their echogenic characteristics as predominantly echolucent, mixed and predominantly echogenic with under 30, 30-70 and over 70% of the total plaque area echogenicity, respectively. RESULTS: From the total cohort 29 (15.8%) subjects had the II, 86 (46.7%) the ID and 69 (37.5%) the DD ACE genotypes. The mean carotid artery diameter stenosis was 37+/-17%, 43+/-19% and 40+/-20% (p=NS) and the intima media thickness was 0.94+/-0.24 mm, 0.97+/-0.20 mm and 0.98+/-0.20 mm (p=NS) in the II, ID and DD subgroups, respectively. When the echogenicity was analyzed according to the ACE I/D polymorphism, 12 subjects (41.4%), 13 (44.8%) and 4 (13.8%) with II genotype had predominantly echogenic, mixed and predominantly echolucent lesions, respectively. The ID genotype diabetics were found to have predominantly echogenic plaques in 41 cases (47.7%), mixed in 30 (34.9%) and predominantly echolucent in 15 cases (17.4%). From the 69 DD subjects 19 (27.5%) had predominantly echogenic plaques, 26 (37.7%) had mixed and 24 (34.8%) had predominantly echolucent lesions. Predominantly echolucent plaques were more frequently encountered among diabetics with the DD genotype (p<0.05), even after correction for demographic characteristics, the main risk factors of atherosclerosis and blood glucose control. CONCLUSIONS: The ACE genotype seems to be associated with the echogenicity of carotid artery atheromatosis but not with the common carotid artery intima media thickness or the degree of internal carotid artery stenosis in subjects with type 2 diabetes mellitus. The DD genotype may be implicated in the increased cardiovascular risk that characterizes echolucent plaques.


Asunto(s)
Enfermedades de las Arterias Carótidas/enzimología , Enfermedades de las Arterias Carótidas/genética , Arteria Carótida Común/enzimología , Diabetes Mellitus Tipo 2/enzimología , Diabetes Mellitus Tipo 2/genética , Eliminación de Gen , Peptidil-Dipeptidasa A/genética , Polimorfismo Genético/genética , Anciano , Proteína C-Reactiva/metabolismo , Enfermedades de las Arterias Carótidas/complicaciones , Arteria Carótida Común/diagnóstico por imagen , LDL-Colesterol/sangre , Diabetes Mellitus Tipo 2/complicaciones , Femenino , Frecuencia de los Genes/genética , Genotipo , Hemoglobina Glucada/metabolismo , Grecia , Humanos , Hiperlipidemias/complicaciones , Hiperlipidemias/enzimología , Hiperlipidemias/genética , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Índice de Severidad de la Enfermedad , Ultrasonografía
18.
Dentomaxillofac Radiol ; 42(6): 20120199, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23503807

RESUMEN

OBJECTIVES: To assess the position of the temporomandibular joint (TMJ) disc in patients with TMJ pain and compare it with equivalent published data of asymptomatic volunteers. METHODS: The oblique coronal closed- and open-jaw MR images from 66 patients with TMJ pain were evaluated. Clinical examination followed the research diagnostic criteria for temporomandibular disorders. In all coronal images, the transverse condylar axis and the medial and lateral edges of the disc were determined using special software. Inter-rater agreement was calculated [two raters; inter-rater correlation coefficient (ICC)]. The presence of osteoarthrosis (OA) was determined by two independent raters. The influence of OA was estimated in patients (generalized estimation equation model). The results were compared with those of healthy volunteers (t-test). Differences between closed and open jaw in patients were analysed with the Wilcoxon matched-pair test. RESULTS: The ICC was good for the transverse condylar axis (0.987) and the medial edge of the disc (0.799) and fair for the lateral edge (0.355). On average, the disc projected 5.5% to the medial side; laterally, the condyle was partially uncovered by the disc (-16.6%). In the open-jaw position, both the medial and the lateral edges shifted medially (to 17.6% vs -23.6%, Wilcoxon matched-pair test, p < 0.001). OA had no significant influence (generalized estimation equation model, p = 0.952). The disc position differed significantly from asymptomatic individuals (t-test, p < 0.001) who showed a medial disc position and full coverage of the condyle. CONCLUSIONS: In patients with TMJ pain, the disc seems to be smaller and located less medially than in healthy volunteers. The extent of the medial shift on opening was similar.


Asunto(s)
Dolor Facial/diagnóstico , Imagen por Resonancia Magnética/métodos , Disco de la Articulación Temporomandibular/patología , Trastornos de la Articulación Temporomandibular/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/estadística & datos numéricos , Masculino , Cóndilo Mandibular/patología , Persona de Mediana Edad , Variaciones Dependientes del Observador , Osteoartritis/diagnóstico , Rango del Movimiento Articular/fisiología , Estudios Retrospectivos , Adulto Joven
19.
Arch Oral Biol ; 58(12): 1751-60, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24200301

RESUMEN

OBJECTIVE: The purpose of this study was to test the hypothesis that jaw clenching induces co-contraction and low-level long-lasting tonic activation (LLTA) of neck muscles in the supine position. DESIGN: Ten healthy subjects developed various feedback-controlled submaximum bite forces in different bite-force directions in supine position. The electromyographic (EMG) activity of the semispinalis capitis, semispinalis cervicis, multifidi, splenius capitis, levator scapulae, trapezius, sternocleidomastoideus, masseter and infra/supra-hyoidal muscles was recorded. For normalization of EMG data, maximum-effort tasks of the neck muscles were performed. RESULTS: Co-contractions of the posterior neck muscles varied between 2% and 11% of their maximum voluntary contraction. Different bite forces and bite-force directions resulted in significant (p<.05) activity differences between the co-contraction levels of the neck muscles. In addition, LLTA of specific neck muscles, provoked by the jaw clenching tasks, was observed. CONCLUSIONS: This study demonstrated for the first time moderate co-contractions of jaw and neck muscles in the supine position under controlled submaximum jaw clenching forces. LLTA of most neck muscles was observed, outlasting clenching episodes and indicating an additional neuromuscular interaction between the two muscle groups.


Asunto(s)
Fuerza de la Mordida , Bruxismo/fisiopatología , Maxilares/fisiología , Músculo Masetero/fisiología , Contracción Muscular/fisiología , Músculos del Cuello/fisiología , Electromiografía/métodos , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Posición Supina , Adulto Joven
20.
Vet J ; 192(2): 140-7, 2012 May.
Artículo en Inglés | MEDLINE | ID: mdl-21924652

RESUMEN

Systematic reviews and meta-analyses of animal studies are important for improving estimates of the effects of treatment and for guiding future clinical studies on humans. The purpose of this systematic review was to assess the methodological quality of systematic reviews and meta-analyses of animal studies in dentistry through using a validated checklist. A literature search was conducted independently and in duplicate in the PubMed and LILACS databases. References in selected systematic reviews were assessed to identify other studies not captured by the electronic searches. The methodological quality of studies was assessed independently and in duplicate by using the AMSTAR checklist; the quality was scored as low, moderate, or high. The reviewers were calibrated before the assessment and agreement between them was assessed using Cohen's Kappa statistic. Of 444 studies retrieved, 54 systematic reviews were selected after full-text assessment. Agreement between the reviewers was regarded as excellent. Only two studies were scored as high quality; 17 and 35 studies were scored as medium and low quality, respectively. There is room for improvement of the methodological quality of systematic reviews of animal studies in dentistry. Checklists, such as AMSTAR, can guide researchers in planning and executing systematic reviews and meta-analyses. For determining the need for additional investigations in animals and in order to provide good data for potential application in human, such reviews should be based on animal experiments performed according to sound methodological principles.


Asunto(s)
Investigación Dental/normas , Odontología , Proyectos de Investigación/normas , Experimentación Animal , Animales , Lista de Verificación , Metaanálisis como Asunto , Literatura de Revisión como Asunto
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