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1.
Clin Radiol ; 75(2): 123-130, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31676038

RESUMEN

AIM: To investigate the diagnostic performance of proton density fat fraction (PDFF) and simultaneous R2* for focal vertebral bone marrow lesion (VBML) assessment, compared with the apparent diffusion coefficient (ADC). MATERIALS AND METHODS: One hundred and ninety-two spinal magnetic resonance imaging (MRI) examinations performed in 126 patients with focal VBMLs from March 2016 to November 2018 were reviewed retrospectively. The lesions were divided into metastases and benign VBMLs. The protocol consisted of routine morphological MRI sequences, followed by complex-based chemical shift imaging (CSE)-MRI and diffusion-weighted (DW)-MRI with a 1.5 T system. PDFF, R2*, and the ADC values were compared using the Mann-Whitney U-test. Receiver operating characteristic curve analysis was carried out to assess the diagnostic performance for differentiating metastases from focal benign VBMLs. RESULTS: PDFF, R2*, and mean ADC values in metastases were significantly lower than those in benign VBMLs (p<0.05). The PDFF (area under the curve [AUC]= 0.968; 95% confidence interval [CI]=0.932-0.988) showed a significantly larger AUC compared with R2* (AUC=0.670; 95% CI=0.599-0.736) and ADC (AUC=0.801; 95% CI=0.738-0.855). The optimal cut-off value of the PDFF for predicting metastases was 9%; this threshold corresponded to a sensitivity of 96.67%, specificity of 90.28%, and accuracy of 94.27%. CONCLUSION: PDFF is significantly more accurate than ADC and R2* for differentiating focal benign VMBLs from metastases.


Asunto(s)
Médula Ósea/diagnóstico por imagen , Columna Vertebral/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Enfermedades de la Médula Ósea/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética , Femenino , Humanos , Imagen por Resonancia Magnética , Espectroscopía de Resonancia Magnética , Masculino , Persona de Mediana Edad , Curva ROC , Estudios Retrospectivos , Neoplasias de la Columna Vertebral/diagnóstico por imagen , Neoplasias de la Columna Vertebral/secundario , Adulto Joven
2.
Osteoporos Int ; 30(7): 1533-1536, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31016352

RESUMEN

This case report describes a case of an elderly woman diagnosed with acute osteoporotic vertebral compression fracture (OVCF) at thoracic spine after using an electrical automated massage chair (EAMC). Care should be taken when using an EAMC, especially by those with or at risk of developing osteoporosis. Osteoporotic vertebral compression fracture (OVCF) is a common problem among elderly population and presents a high burden to society. Osteoporotic fractures may occur after a minimal trauma of the vertebrae. Electrical automated massage chair (EAMC) is a device that uses a programmed algorithm to perform automated massage. The massage chair, a popular device among elderly with back pain, relies on friction and rhythmic tapping created by a motorized roller. However, research regarding the safety of this device is lacking, especially in the perspective of OVCF. We present a case of an elderly woman diagnosed with acute OVCF of the thoracic spine after using an EAMC. The patient had no risk factor for fragility fracture and experienced an abrupt onset of severe upper back pain while using EAMC. Imaging studies revealed an isolated acute compression fracture at T8 vertebra (AO classification type A1) while dual-energy X-Ray absorptiometry scan confirmed osteoporosis. The patient was treated with a plastic orthosis and oral medications for osteoporosis. After 6-months follow-up, the patient showed union of the fractured T8 vertebra and no remaining symptoms. This case highlights that OVCF can be induced by EAMC. Therefore, patients with or at risk for osteoporosis should be cautious while opting for deep tissue massage using EAMC.


Asunto(s)
Fracturas por Compresión/etiología , Masaje/efectos adversos , Fracturas Osteoporóticas/etiología , Fracturas de la Columna Vertebral/etiología , Anciano , Femenino , Fracturas por Compresión/diagnóstico por imagen , Humanos , Masaje/instrumentación , Fracturas Osteoporóticas/diagnóstico por imagen , Radiografía , Fracturas de la Columna Vertebral/diagnóstico por imagen , Vértebras Torácicas/diagnóstico por imagen , Vértebras Torácicas/lesiones
3.
J Nanosci Nanotechnol ; 13(5): 3331-4, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23858853

RESUMEN

In this paper, we fabricate planar-type Silicon-Oxide-High-k-Oxide-Silicon (SOHOS) and the planar-type SOHOS devices with N2 implantation of 3 x 10(15) dose in a tunneling oxide to determine the impact of N2 implantation in the tunneling oxide of a memory device. The N2 implantation device has better retention characteristics than the device with no implantation. In order establish the correlation between N2 implantation and retention characteristic improvement, the low frequency noise (1/f noise) characteristic is investigated. The normalized drain current noise (S(ID)/I(D)2) level of the N2 implantation device is higher than that of the device with no implantation, which means that N2 implantation causes more trap formation near the interface. Considering that N2 implantation does not affect the DC transfer characteristics, such as mobility and sub-threshold slope, this finding indicates that the increase in the 1/f noise level is due to oxide traps rather than to interface traps. Therefore, the retention characteristic improvement in the N2 implantation device can be explained by the generation of higher number of oxide traps and an increase in the potential barrier blocking the leakage path in the tunneling oxide.


Asunto(s)
Equipos de Almacenamiento de Computador , Nanoestructuras/química , Nanoestructuras/ultraestructura , Semiconductores , Dióxido de Silicio/química , Diseño de Equipo , Análisis de Falla de Equipo , Ensayo de Materiales
4.
Osteoporos Int ; 22(8): 2385-93, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20963399

RESUMEN

UNLABELLED: Three modifiable factors of fall direction, poor bone strength, and depression were associated with an increased risk of hip fractures for elderly men and women; fall direction was a much stronger predictor than the other two. When a fall occurs, changing fall direction may be most effective to prevent hip fractures. INTRODUCTION: A matched case-control study was conducted to identify risk factors for hip fractures in elderly men and women in Taiwan. METHODS: Cases were defined as persons who visited the emergency room due to a fall and were diagnosed with a first hip fracture. For each case, a control was matched by gender and time of falling, selected from persons who sought care at the same emergency room due to a fall resulting in injury other than a hip fracture. In total, 85 paired men and 221 paired women were included. RESULTS: For men, backward, straight-down, and sideways falls were associated with 10.8-, 13.6-, and 15.2-fold increased risks of hip fractures, respectively, compared with forward falls. Poor bone strength and depression were associated with 2.27- and 2.85-fold increased risks of hip fractures, respectively, while dependence in ≥3 activities of daily living was associated with a fivefold lower risk. For women, compared with forward falls, backward, straight-down, and sideways falls were associated with 10.2-, 9.86-, and 12.8-fold increased risks of hip fractures, respectively. Living in a rented house, poor bone strength, depression, and use of antidiabetics were associated with 1.65-, 2.78-, 1.89-, and 1.92-fold increased risks of hip fractures, respectively. Hormone replacement therapy was associated with a fivefold lower risk of hip fractures. CONCLUSIONS: While bone strength and depression can be risk factors for hip fractures in elderly people, the direction of the fall was the strongest predictor. Some risk factors differed between elderly men and women.


Asunto(s)
Accidentes por Caídas , Fracturas de Cadera/etiología , Fracturas Osteoporóticas/etiología , Actividades Cotidianas , Anciano , Anciano de 80 o más Años , Densidad Ósea , Estudios de Casos y Controles , Enfermedad Crónica , Depresión/complicaciones , Femenino , Fracturas de Cadera/fisiopatología , Humanos , Masculino , Fracturas Osteoporóticas/fisiopatología , Factores de Riesgo , Taiwán
5.
Mol Cell Biol ; 11(10): 5222-8, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1922042

RESUMEN

Human T-cell lymphotropic virus type I (HTLV-I) has been associated with an adult form of T-cell leukemia as well as tropical spastic paraparesis, a neurodegenerative disease. Adult T-cell leukemia patients express high levels of the type 1 isoform of transforming growth factor-beta (TGF-beta 1), which is mediated by the effects of the HTLV-I Tax transactivator protein on the TGF-beta 1 promoter. To understand further the regulation of TGF-beta 1 expression by Tax, we examined its expression in transgenic mice carrying the HTLV-I tax gene. We show that tumors from these mice and other tissues, such as submaxillary glands and skeletal muscle, which express high levels of tax mRNA selectively express high levels of TGF-beta 1 mRNA and protein. Moreover, TGF-beta 1 significantly stimulated the incorporation of tritiated thymidine into one of three cell lines derived from neurofibromas of tax-transgenic mice, which suggests that the excessive production of TGF-beta 1 may play a role in tumorigenesis and that these mice may serve as a useful model for studying the biological effects of TGF-beta in vivo.


Asunto(s)
Regulación Neoplásica de la Expresión Génica/fisiología , Genes pX/genética , Factor de Crecimiento Transformador beta/genética , Animales , Northern Blotting , División Celular/genética , Ensayo de Inmunoadsorción Enzimática , Virus Linfotrópico T Tipo 1 Humano/genética , Humanos , Masculino , Ratones , Ratones Transgénicos/genética , Ratones Transgénicos/metabolismo , Regiones Promotoras Genéticas/fisiología , Provirus/genética , Factor de Crecimiento Transformador beta/biosíntesis , Células Tumorales Cultivadas
6.
Mol Cell Biol ; 10(9): 4978-83, 1990 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-2117705

RESUMEN

Growth factor-independent 32D-src and 32D-abl cell lines, established by infecting the interleukin-3-dependent myeloid precursor cell line (32D-123) with retroviruses containing the src or abl oncogene, were used to study transcriptional regulation of transforming growth factor beta 1 (TGF-beta 1) mRNA. Analysis of different TGF-beta 1 promoter constructs regulated by pp60v-src indicated that sequences responsive to high levels of src induction contain binding sites for AP-1. Both src and serum induced expression of the c-fos and c-jun genes in myeloid cells, resulting in transcriptional activation of the TGF-beta 1 gene. We found that serum treatment increased TGF-beta 1 mRNA levels in 32D-123 cells and that the v-Src protein could replace the serum requirement by stimulating binding to the AP-1 complex of the TGF-beta 1 promoter, thereby mediating the induction of TGF-beta 1 transcription.


Asunto(s)
Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica , Proteína Oncogénica pp60(v-src)/metabolismo , Regiones Promotoras Genéticas , Proteínas Tirosina Quinasas/metabolismo , Factores de Transcripción/metabolismo , Transcripción Genética , Factores de Crecimiento Transformadores/genética , Animales , Secuencia de Bases , Línea Celular , Proteínas de Unión al ADN/genética , Ratones , Datos de Secuencia Molecular , Sondas de Oligonucleótidos , Plásmidos , Proteínas Proto-Oncogénicas c-jun , Factores de Transcripción/genética
7.
Eur J Surg Oncol ; 32(4): 405-9, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16524688

RESUMEN

AIM: To performed a prospective investigation of the relative merits of rapid cytokeratin immunohistochemical (CK-IHC) staining of the SLN removed during the operation of breast cancer patients. STUDY DESIGN: Between December 2002 and March 2004, 62 patients with T1 and T2 breast cancer were enrolled after undergoing successful sentinel lymph node biopsy. Eighty-nine sentinel lymph nodes (mean number, 1.44) were biopsied and first examined by hematoxylin-eosin (H&E) stained frozen section. All the tumour free sentinel lymph nodes by H&E stained frozen section were immunostained for cytokeratin using a rapid immunohistochemical assay (Cytokeratin (PAN), 1:50, Novocastra Lab., Newcastle, UK) during the operations. RESULTS: Rapid IHC staining revealed seven positive sentinel lymph nodes that were negative for metastasis by H&E staining. This study showed a sensitivity of 92.86%, a specificity of 100%, an accuracy of 98.9%, and a negative predictive value of 98.7%. CONCLUSIONS: The intraoperative examination of sentinel lymph nodes is an accurate and effective way of predicting the axillary lymph node status of patients with breast cancers.


Asunto(s)
Neoplasias de la Mama/patología , Escisión del Ganglio Linfático , Ganglios Linfáticos/patología , Biopsia del Ganglio Linfático Centinela , Adulto , Anciano , Axila , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/cirugía , Femenino , Estudios de Seguimiento , Humanos , Inmunohistoquímica , Cuidados Intraoperatorios/métodos , Queratinas/metabolismo , Ganglios Linfáticos/metabolismo , Persona de Mediana Edad , Estudios Prospectivos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
8.
Eur J Cardiothorac Surg ; 27(4): 671-4, 2005 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-15784372

RESUMEN

OBJECTIVE: Video-assisted thoracoscopic (VATS) bullectomy and apical pleurectomy has become the preferred procedure for recurrent or complicated primary spontaneous pneumothorax (SPN). Although thoracic epidural analgesia is the gold standard after open thoracic surgical procedures, its use in the management of minimally invasive procedures in this young population has not been extensively studied. METHODS: From 1997 to 2003, a single surgeon performed 118 consecutive VATS pleurectomies for primary SPN. The perioperative course, analgesic requirements, hospital stay and long-term complications were compared for 22 (18%) patients in whom a patient-controlled thoracic epidural was used for analgesia and 96 (82%) patients who did not receive an epidural (parenteral opioids). A four-point verbal pain score (0-3) was recorded hourly in every patient at rest and on coughing following surgery. RESULTS: One patient required additional surgery for evacuation of haemothorax. There were no mortalities or other major complications in the series. Overall median hospital stay was 3 (range 1-10) days, the incidence of long-term pain at 3 months was 6%, and the long-term recurrence rate was 3%. Despite parenteral opioids being discontinued significantly earlier than epidurals, pain scores were similar in both groups. There were no significant differences in the duration of air-leaks, length of drainage, hospital stay, long-term pain and long-term paraesthesias between the two groups. CONCLUSIONS: Thoracic epidural analgesia does not contribute significantly to minimize neither perioperative nor long-term pain after VATS pleurectomy for primary SPN. The additional resource requirement in these patients is not justified.


Asunto(s)
Analgesia Epidural/métodos , Dolor Postoperatorio/tratamiento farmacológico , Pleura/cirugía , Neumotórax/cirugía , Cirugía Torácica Asistida por Video , Adolescente , Adulto , Analgesia Controlada por el Paciente/métodos , Femenino , Humanos , Tiempo de Internación , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Dimensión del Dolor , Cirugía Torácica Asistida por Video/efectos adversos
9.
Minerva Cardioangiol ; 63(6): 495-505, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25283168

RESUMEN

AIM: The effects of beta-blockers in pediatric and congenital heart disease (CHD) patients suffering from heart failure are controversial. We performed a meta-analysis to determine whether beta-blockers are effective for heart failure in pediatric and CHD patients. METHODS: We searched for clinical trials focusing on clinical on clinical and ventricular functional/dimensional changes after beta-blocker therapy in PubMed (from its inception to August 2013) and bibliographies of identified studies. Studies investigating any of three beta blockers (carvedilol, bisoprolol, and extended release metoprolol succinate) which are known to be effective in adult patients with heart failure were included. RESULTS: Of the 158 screened, 17 (N.=476) fulfilled the study criteria and were analyzed. Beta-blockers were associated with significant improvements in left ventricular (LV) ejection fraction (EF) (12.47%; 95% CI, 10.36 to 14.61), fraction shortening (5.75%; 95% CI, 4.42 to 7.08), LV end-diastolic dimension (-2.91 mm; 95% CI, -5.46 to -0.36), and LV systolic dimension (-4.03 mm; 95% CI, -6.81 to -1.25). No significant change in the pooled mean difference of the right ventricular (RV) EF (3.50%; P=0.08) was observed. However, the RV EF in the untreated group showed a deteriorating trend (-3%), which was different from the trend in the treatment group. There was a significant reduction in the incidence of clinical worsening (odds ratio, 2.15; 95% CI, 1.27 to 3.66). CONCLUSION: Beta-blocker therapy was associated with a significant improvement of echocardiographic parameters in patients with systemic LV failure. However, the use of beta-blockers did not provide significant benefits in terms of improving the EF in patients with RV failure. Nonetheless, beta-blockers may be effective to prevent the clinical deterioration of pediatric and CHD patients with heart failure.


Asunto(s)
Antagonistas Adrenérgicos beta/uso terapéutico , Cardiopatías Congénitas/tratamiento farmacológico , Insuficiencia Cardíaca/tratamiento farmacológico , Factores de Edad , Bisoprolol/uso terapéutico , Carbazoles/uso terapéutico , Carvedilol , Niño , Cardiopatías Congénitas/fisiopatología , Insuficiencia Cardíaca/fisiopatología , Humanos , Metoprolol/uso terapéutico , Propanolaminas/uso terapéutico , Disfunción Ventricular Izquierda/tratamiento farmacológico
10.
Cancer Lett ; 133(1): 47-56, 1998 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-9929159

RESUMEN

The urinary concentrations of 16 estrogens and 11 polyamines were quantitatively determined by gas chromatography-mass spectrometry and gas chromatography with nitrogen-phosphorus detection. Samples from patients with stages I-IV of breast cancer (35 cases, aged 27-65 years) as well as from age-matched normal female subjects (25 cases, aged 22-61 years) were tested. Also, the ratios of precursor to product metabolite including 16alpha-OH E1 to 2-OH E1, which are linked to estrogen and polyamine biosynthetic pathways, were determined to explore enzyme involvement in breast cancer and to evaluate the potential usefulness of these ratios and concentrations as disease staging markers. It was confirmed that major estrogens and 16a-OH E1 were positively associated with breast cancer and catechol estrogens including 2-OH E1 were inversely associated with breast cancer. The ratios of N1-acSp/Spd and 16alpha-OH E1/2-OH E1 might be a useful dual marker for staging of breast cancer. From the variation of the relative ratios of polyamines, it is suggested that alteration in polyamine oxidase (PAO) activity may play an important role in the development of breast cancer.


Asunto(s)
Poliaminas Biogénicas/orina , Neoplasias de la Mama/orina , Estrógenos/orina , Adulto , Neoplasias de la Mama/patología , Femenino , Cromatografía de Gases y Espectrometría de Masas , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias
11.
Am J Med Genet ; 87(5): 395-8, 1999 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-10594877

RESUMEN

Duplication of distal 15q results in a recognizable clinical phenotype. We report here on a 25-day-old boy with a de novo interstitial duplication of chromosome region 15q15-q24. The manifestations in this patient are milder than those of previously described patients and include minor facial anomalies, velopharyngeal insufficiency, branchial cleft cyst, and hydronephrosis. Fluorescence in situ hybridization (FISH) using a chromosome 15 painting probe confirmed that the extra material is of chromosome 15 origin. Further analysis with the SNRPN probe demonstrated that the duplication is telomeric to the Prader-Willi/Angelman syndrome critical region. This case delineates a broader spectrum for patients with duplication 15q syndrome.


Asunto(s)
Anomalías Múltiples/genética , Cromosomas Humanos Par 15 , Duplicación de Gen , Branquioma/genética , Bandeo Cromosómico , Facies , Humanos , Hidronefrosis/genética , Hibridación Fluorescente in Situ , Recién Nacido , Masculino , Fenotipo , Síndrome , Insuficiencia Velofaríngea/genética
12.
Histol Histopathol ; 16(4): 1149-59, 2001 10.
Artículo en Inglés | MEDLINE | ID: mdl-11642735

RESUMEN

To investigate the in vivo effects of Staphylococcal enterotoxin B (SEB) on dendritic cells (DCs) in the spleen, a single dose of SEB (50 microg/kg) was administered to BALB/c mice by intraperitoneal injection. Afterwards, the mice were sacrificed at 2, 6 and 24 hr, 2, 4, 7 and 15 days, and the spleens were removed. The immunocytochemical characterization of the cells was carried out using various monoclonal antibodies in cryostat-cut sections. The distribution patterns of DCs and their major costimulatory molecules, CD80, CD86 and CD40 in the spleen were identified, and the evidence for maturation of DCs in vivo in response to SEB was obtained. It was found that systemic administration of SEB induced the migration of most of the immature, splenic DCs from the marginal zone to the periarterial lymphatic sheath within 6 hr. This movement paralleled a maturation process, as assessed by upregulation of CD40, CD80 and CD86 expression in the interdigitating dendritic cells (IDCs). The upregulation of costimulatory molecule expression was conspicuous only in DCs in contrast to other antigen-presenting cells (APCs) such as macrophages and B cells which did not show any significant alterations in their costimulatory molecule expression. We also demonstrated the temporal expression pattern of these costimulatory molecules on the activated DCs. The upregulation of costimulatory molecules on DCs reached a peak level 6 hr after SEB injection, while the increase in number of T cells expressing T cell receptor V138 reached a peak level on day 2 after SEB treatment. In conclusion, we demonstrated the in vivo DC response to SEB in the mouse spleen, especially a potent stimulative effect of SEB on DCs in vivo, a temporal distribution pattern of DCs as well as T cells including TCR Vbeta8+ T cells, and a differential expression pattern of costimulatory molecules on the activated DCs. The results of the present study indicate that DCs are the principal type of APCs which mediate T cell activation by SAg in vivo, and that each costimulatory molecule may have different role in the activation of DCs by SAg. Thus, it is plausible to speculate that DCs play a critical role in the T cell clonal expansion by SAgs and other SAg-induced immune responses in vivo.


Asunto(s)
Presentación de Antígeno , Antígenos Bacterianos/inmunología , Células Dendríticas/inmunología , Enterotoxinas/inmunología , Bazo/inmunología , Superantígenos/inmunología , Animales , Presentación de Antígeno/efectos de los fármacos , Antígenos Bacterianos/toxicidad , Complejo CD3/inmunología , Antígenos CD4/inmunología , Antígenos CD8/inmunología , Células Dendríticas/efectos de los fármacos , Enterotoxinas/toxicidad , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Ratones , Bazo/efectos de los fármacos , Bazo/inervación , Superantígenos/toxicidad
13.
J Appl Physiol (1985) ; 87(5): 1651-5, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10562604

RESUMEN

The purpose of this study was to investigate whether the isometric muscle force, redeveloped following maximal-effort voluntary shortening contractions in human skeletal muscle, is smaller than the purely isometric muscle force at the corresponding length. Isometric knee extensor moments, surface electromyographic (EMG) signals of quadriceps femoris, and interpolated twitch moments (ITMs) were measured while 10 subjects performed purely isometric knee extensor contractions at a 60 degrees knee angle and isometric knee extensor contractions at a 60 degrees knee angle preceded by maximal-effort voluntary shortening of the quadriceps muscles. It was found that the knee extensor moments were significantly decreased for the isometric-shortening-isometric contractions compared with the isometric contractions for the group as a whole, whereas the corresponding EMG and ITM values were the same. This study is the first to demonstrate force depression following muscle shortening for voluntary contractions. We concluded that force depression following muscle shortening is an actual property of skeletal muscle rather than a stimulation artifact and that force depression during voluntary contraction is not accompanied by systematic changes in muscle activation as evaluated by EMG and ITM.


Asunto(s)
Músculo Esquelético/fisiología , Adulto , Electromiografía , Femenino , Humanos , Contracción Isométrica/fisiología , Rodilla/fisiología , Masculino , Contracción Muscular/fisiología
14.
J Biomech ; 33(8): 917-23, 2000 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10828321

RESUMEN

The purpose of this study was to determine the influence of speed and distance of muscle shortening on the amount of force depression for voluntary contractions. Two experimental tests were performed. In the first test, subjects performed isometric knee extensor contractions following muscle shortening produced by isokinetic knee extensions over the range 25-50 degrees. In the second test, subjects performed isometric knee extensor contractions following muscle shortening produced by isokinetic knee extensions at two speeds: 20 and 240 degrees /s. Knee extensor moments, surface electromyographical (EMG) signals of quadriceps femoris, and interpolated twitch moments were measured during all contractions and were compared with the corresponding values obtained during purely isometric contractions. Force depression following muscle shortening for the voluntary contractions tested in this study did not depend on the distance or the speed of muscle shortening. These results are in contrast to the corresponding results in the literature obtained using artificial electrical stimulation in which force depression was always found to be directly related to the distance of shortening and inversely related to the speed of shortening. The difference in force depression as a function of the distance and speed of muscle shortening between voluntary and artificial electrical stimulation may be associated with changes in activation following the voluntary shortening contractions, whereas activation is controlled and constant in all artificial stimulation protocols.


Asunto(s)
Contracción Muscular/fisiología , Adulto , Fenómenos Biomecánicos , Estimulación Eléctrica , Electrodos , Electrofisiología , Nervio Femoral/fisiología , Humanos , Contracción Isométrica/fisiología , Movimiento/fisiología , Músculo Esquelético/fisiología
15.
J Biomech ; 34(8): 979-87, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11448689

RESUMEN

Muscle shortening and stretch are associated with force depression and force enhancement, respectively. Previously, we have investigated the effect of combined dynamic contractions (i.e. a single shortening-stretch and stretch-shortening cycle) on force production (Herzog and Leonard, 2000). In order to investigate the relationship between force depression and force enhancement systematically, we studied the effects of a single as well as multiple stretch-shortening and shortening-stretch cycles on the ascending limb of the force-length relationship. Furthermore, by systematically varying the speed and magnitude of stretch preceding shortening and the speed and magnitude of shortening preceding stretch, we investigated the influence of these varying contractile conditions on force depression and force enhancement, respectively. Test contractions were performed on cat soleus (n=6) by electrical stimulation using four conceptually different protocols containing a single or repeated stretch-shortening and shortening-stretch cycles. The results of this study showed that: (1) force depression was not influenced by stretch preceding shortening independent of the speed and amount of stretch; (2) force enhancement was influenced in a dose-dependent manner by the amount of shortening preceding stretch but was not affected by the speed of shortening; (3) repeated stretch-shortening (shortening-stretch) cycles showed cumulative effects; (4) the number of shortening steps over a given distance did not influence the amount of force depression. The findings of this study support the idea that the mechanism of force depression associated with muscle shortening is different from that of force enhancement associated with muscle stretch. Furthermore, they support and extend our previous findings that stretch-shortening and shortening-stretch cycles are not commutative.


Asunto(s)
Contracción Muscular/fisiología , Músculo Esquelético/fisiología , Análisis de Varianza , Animales , Fenómenos Biomecánicos , Gatos
16.
Yonsei Med J ; 38(4): 206-11, 1997 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-9339128

RESUMEN

To evaluate the prognostic significance of bcl-2, we investigated the correlation of bcl-2 expression with the established indicators of prognosis and tumor behavior in breast cancer. This study included a patient group of 91 histologically diagnosed female breast carcinomas. To determine the bcl-2 immunoreactivity, we used a monoclonal antibody directed against the bcl-2 protein by immunohistochemistry from paraffin-embedded tissue in a series of 91 women with breast cancer. Interpretable DNA histograms were obtained from 84 patients. The median age at diagnosis was 45.5 years and the median follow-up time was 30.5 months. Forty-eight (52.7%) cancers showed the bcl-2 immunoreactivity in the cytoplasm. The nonneoplastic portion of ductal epithelial cells and normal lymphocytes were usually stained with bcl-2 antibody. Estrogen receptors (ER)(p < 0.001) and progesterone receptors (PR)(p < 0.001) showed strong positive correlation with bcl-2 immunoreactivity. The histologic grade (p < 0.05) and nuclear grade (p < 0.01) also showed positive relationships with bcl-2 positivity but tumor size (p > 0.05) and DNA ploidy (p > 0.05) were not related with it. The bcl-2 positive patients showed longer survival (p < 0.05) compared to bcl-2 negative tumors in univariate analysis (Kaplan-Meier life table analysis). Using multivariate analysis with Cox regression, bcl-2 (p > 0.05), nuclear grade (p > 0.05), ER status (p > 0.1) and PR status(p > 0.1) were not reliable indicators for overall survival except histologic grade (p < 0.05). Our results suggest that bcl-2 expression may be related to hormonal regulation and tumor differentiation in breast carcinoma. Larger patient study groups with a longer follow-up period will be helpful to clarify the prognostic significance of bcl-2.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Carcinoma in Situ/metabolismo , Carcinoma in Situ/patología , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patología , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Femenino , Humanos , Persona de Mediana Edad , Receptores de Estrógenos/metabolismo , Receptores de Progesterona/metabolismo
17.
Yonsei Med J ; 41(3): 345-53, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10957889

RESUMEN

Cyclin/cdc complexes are known to function in cell-cycle regulation. Cyclin D1/cdk4 and -6 complexes, which functions as a G1-S checkpoint and cyclin B1/cdc2 complexes, a G2-M checkpoint are essential for DNA synthesis and mitosis, respectively. Thus, dysregulated overexpression of cyclins appears to be involved in uncontrollable cell proliferation and early tumor development. We investigated the expression and proliferative index of cyclin D1 (PIcyclin D1), cyclin B1 (PIcyclin B1) and Ki-67 (PIKi-67) using immunohistochemical staining on 15 cases of ductal hyperplasia (DH), 26 cases of atypical ductal hyperplasia (ADH) and 43 cases of ductal carcinoma in situ (DCIS) of the breast in order to evaluate whether these cyclins are associated with abnormal cell proliferation and play a role in tumor development from ADH to carcinoma. Furthermore, we investigated whether the expression and proliferative index of the cyclins and Ki-67 are correlated with the histologic grade according to the Van Nuys classification and with the histologic subtype according to traditional classification. Finally, we estimated the correlation coefficient among PIcyclin D1, PIcyclin B1, PIKi-67 and estrogen receptor in ADH and DCIS. The expression of cyclin D1 was detected in 39.5% of DCIS and 7.7% of ADH cases. In the DH cases, expression of cyclin D1 was not found. Expression of cyclin B1 was also detected in 69.7% of DCIS, 50.0% of ADH and 93.3% of the DH cases. The PIcyclin D1 was significantly different among these three groups. Moreover, the PIcyclin D1 and PIKi-67 were differed significantly between the low grade DCIS and ADH cases. However, PIcyclin B1 only appeared to be significantly different between the total DCIS and ADH. Results of the correlation coefficient among PIcyclin D1, PIcyclin B1 and PIKi-67 were positively correlated with each other. No significant correlation was found between the expression of ER and cyclin D1 in ADH and DCIS. In summary, our results support the hypothesis that a cyclin D1 and cyclin B1 protein aberration, along with Ki-67, may act as a relatively early event in the tumor development from ADH to carcinoma.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Mama/metabolismo , Mama/patología , Carcinoma Ductal de Mama/metabolismo , Carcinoma Ductal de Mama/patología , Ciclinas/metabolismo , Femenino , Humanos , Hiperplasia , Antígeno Ki-67/metabolismo
18.
Yonsei Med J ; 33(3): 272-6, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1292251

RESUMEN

This is the first preliminary report among two consecutive papers. Partial mastectomy(PM), axillary lymph node dissection(AD) and radiotherapy (RT) were performed on seventeen operable breast cancer patients who had been admitted from April 1991 to March 1992 to the department of surgery, Yongdong Severance Hospital for improved cosmetic appearance and better survival rate. Of seventeen patients, 47% were T1 lesion and 76% were stage I and II. Extensive intraductal component(EIC) within or around the tumor was also analyzed. Twenty nine per cent of the patients were EIC positive. The mean number of axillary lymph nodes was 21.5 after PM with AD and 20.5 after mastectomy. For radiotherapy, 4,500 rad was delivered to the breast parenchyma and 1,600 rad of boost to the primary tumor site using the electron beam method after surgery. All patients have since been living well without any local recurrence and were satisfied with breast preservation for the one-year follow-up period. We concluded that the PM, AD and RT can be another surgical treatment modality of breast cancer. A longer follow-up data will be followed on the second paper.


Asunto(s)
Neoplasias de la Mama/terapia , Escisión del Ganglio Linfático , Mastectomía Segmentaria , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Terapia Combinada , Femenino , Humanos , Radioterapia/efectos adversos
19.
Yonsei Med J ; 41(2): 293-7, 2000 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-10817035

RESUMEN

The initial presentation of breast malignancy as noninvasive carcinoma in an area of sclerosing adenosis is unusual. Especially, lobular carcinoma in situ in sclerosing adenosis sometimes can be a potential source of confusion with invasive lobular carcinoma. We report a case of lobular carcinoma in situ presenting in adenosis exhibiting patterns akin to invasive lobular carcinoma, thus leading to potential misdiagnosis. Overall architecture of the lesion as seen at lower power and immunohistochemistry can be useful to distinguish between sclerosing adenosis with lobular carcinoma in situ and infiltrating lobular carcinoma.


Asunto(s)
Neoplasias de la Mama/patología , Carcinoma in Situ/patología , Carcinoma Lobular/patología , Enfermedad Fibroquística de la Mama/patología , Femenino , Humanos , Inmunohistoquímica , Persona de Mediana Edad
20.
Yonsei Med J ; 40(1): 1-8, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10198599

RESUMEN

The purpose of this study was to determine whether 20 patients who received an early postmastectomy rehabilitation treatment program showed more improvement in range of shoulder motion and functional activities than 13 patients who received instruction for exercise only. Data were obtained at preoperatively, three days after operation, at discharge and at postdischarge one month for each patient on parameters such as range of motion of the ipsilateral shoulder joint, upper extremity circumferential measurements, as well as 10 elements of shoulder function. Postoperatively, both groups showed an increased range of motion of the shoulder joint and improved functional activities, but the group that received postoperative rehabilitation management had a better range of shoulder motion and less difficulty in five items for functional assessment. This study also showed that an early rehabilitation program did not increase postoperative complications. We concluded that an early rehabilitation program or intensive instruction program only by a well-trained physical therapist or physiatrist was beneficial to postmastectomy patients in regaining the function and range of shoulder motion, and significantly better in a rehabilitation group.


Asunto(s)
Neoplasias de la Mama/cirugía , Mastectomía/rehabilitación , Adulto , Femenino , Humanos , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Prospectivos
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