Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
1.
Chemistry ; 26(43): 9471-9474, 2020 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-32181527

RESUMEN

Facile synthesis of various benzonaphthofurans was achieved by intramolecular hydroarylation of 1,4-disilyl-2-aryloxy-1,3-enynes followed by cycloaddition with arynes or alkenes and finally desilylaromatization. The three-step transformation can be operated sequentially in one-pot, providing with a range of furanoacenes easily and highly effectively.

2.
J Hip Preserv Surg ; 5(2): 137-149, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29876130

RESUMEN

The coexistence of acetabular dysplasia (AD) and femoroacetabular impingement (FAI) has not been well discussed. This study was performed to elucidate the prevalence and morphological features of AD with coexisting FAI-related findings in a Japanese population. Computed tomography images were retrospectively evaluated. AD was classified as definite or borderline. The morphological findings that defined cam deformity were an α angle of ≥55°, head-neck offset ratio (HNOR) of <0.13, pistol grip deformity positivity and herniation pit positivity. The morphological findings that defined pincer deformity were acetabular index of ≤0° and a retroverted acetabulum. In total, 128 hips (male, 64; female, 64) were analyzed. The prevalence of coexistence of AD and FAI-related findings was detected in 23.4% of hips (definite AD and FAI, 7.8%; borderline AD and FAI, 15.6%). The percentages of hips with AD containing cam or pincer deformities among all were 54.3% and 4.3%, respectively. The percentage of AD with coexisting cam and that of AD with coexisting combined deformities was significantly higher in men, respectively. On the other hand, the most major morphological feature of FAI detected in hips with AD was a HNOR of <0.13. The coexistence of AD and FAI-related findings was common in a Japanese population, and 65.2% of hips with AD had some FAI-related findings. In discussing and managing AD, we recommend paying attention to the coexistence with FAI-related findings, especially in men and in borderline AD. In such hips, the most notable parameter as a morphological feature of FAI is a reduced HNOR.

3.
Angew Chem Int Ed Engl ; 57(7): 1987-1990, 2018 02 12.
Artículo en Inglés | MEDLINE | ID: mdl-29316098

RESUMEN

Whereas aryl(trialkyl)silanes are considered to be ideal organometallic reagents for cross-coupling reactions owing to their stability, low toxicity, solubility, and easy accessibility, they are generally inert under typical cross-coupling conditions. Disclosed herein is a palladium/copper catalytic system that enables the cross-coupling of trimethyl, triethyl, tert-butyldimethyl, and triisopropyl aryl silanes with aryl bromides. This process is applicable to the sequential C-H and C-Si bond arylation of thiophenes and the synthesis of poly(thiophene-fluorene)s.

4.
J Orthop Sci ; 23(2): 365-370, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29276040

RESUMEN

BACKGROUND: The Elite-Plus stem has two shape variations: roundback and flanged. The correlation between the radiographic results and stem geometry has not been previously investigated. The objective of this study was to evaluate the long-term primary total hip arthroplasty results using Elite-Plus stems, and the effect of stem geometry on radiographic distal femoral cortical hypertrophy. METHODS: We retrospectively evaluated, radiographically, 156 patients (173 hips) who underwent total hip arthroplasty between April 1998 and November 2005, and were followed up for >5 years, postoperatively. Radiographic factors affecting distal femoral cortical hypertrophy were analysed using multivariable logistic regression analysis. RESULTS: The mean follow-up period was 11.6 (5-17.8) years. During follow-up, femoral components were revised in 7 hips; one was revised due to aseptic loosening. Another femoral component was loosened and waiting for revision. The 10- and 15-year survival rates for aseptic stem loosening were 100% and 98.1% (95% CI: 92.5-99.5), respectively. Distal femoral cortical hypertrophy occurred in 23 hips (14.8%), and more often with roundback type (34.1%) than with flanged type (7.2%). Distal femoral cortical hypertrophy was observed in 34.8% of hips with valgus alignment, 11.3% with neutral alignment, and 12.5% with varus alignment. Multivariable logistic regression analysis showed that roundback stem shape and valgus stem alignment significantly affected the occurrence of distal femoral cortical hypertrophy. CONCLUSIONS: The Elite-Plus stem has excellent long-term clinical and radiographic results in Japanese patients. The occurrence of distal femoral cortical hypertrophy significantly depends on the shape and alignment of Elite-Plus stems.


Asunto(s)
Artroplastia de Reemplazo de Cadera/métodos , Cabeza Femoral/patología , Prótesis de Cadera , Diseño de Prótesis , Falla de Prótesis , Adulto , Anciano , Anciano de 80 o más Años , Artroplastia de Reemplazo de Cadera/instrumentación , Estudios de Cohortes , Femenino , Cabeza Femoral/diagnóstico por imagen , Estudios de Seguimiento , Humanos , Hipertrofia/diagnóstico por imagen , Hipertrofia/cirugía , Japón , Estimación de Kaplan-Meier , Modelos Logísticos , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estudios Retrospectivos , Medición de Riesgo , Factores de Tiempo , Resultado del Tratamiento
5.
BMC Musculoskelet Disord ; 18(1): 50, 2017 01 31.
Artículo en Inglés | MEDLINE | ID: mdl-28137249

RESUMEN

BACKGROUND: Acetabular dysplasia (AD) is a well-known cause of osteoarthritis (OA) of the hip, with its prevalence previously determined on plain radiography. The prevalence of preexisting AD was reported as 7.3% in a patient-based Asian population. Although computed tomography (CT) could evaluate AD in multiple planes, its prevalence using multiplanar CT images has not been reported. We investigated its prevalence with CT on coronal, axial, and sagittal planes and then determined if adding the axial and sagittal planes enhanced the investigation. METHODS: We retrospectively examined 52 consecutive Japanese individuals (mean age 59.4 years) who had undergone CT for conditions unrelated to hip disorders. The inclusion criteria of CT images were (1) reconstructed axial slice thickness of ≤1 mm and (2) normal pelvic rotations and tilt. Exclusion criteria were (1) age <20 years, (2) neither hip center could be clearly detected, (3) evidence of hip OA. The parameters used to define AD on the coronal plane were the center-edge angle, Sharp angle, acetabular index, acetabular depth ratio, and acetabulum head index. The anterior and posterior acetabular sector angles were used as axial parameters and the vertical-center-anterior margin angle as the sagittal parameter. AD prevalence was calculated using multiplanar images and then compared with the previously reported Asian prevalence using 95% confidence intervals (CI). In this study, we defined "prevalence" as the proportion of subjects who had AD in at least one hip. RESULTS: The mean prevalence of AD on coronal, axial, and sagittal planes was 16.9, 15.4, and 7.7%, respectively. The lowest prevalence found by combining the three planes was 25.0% (95% CI 15.2-38.2%). This prevalence was significantly higher than that in the previously reported Asian population (7.3%). CONCLUSIONS: At the lowest estimate, the prevalence of AD evaluated in three planes was more than twice as high as the previously reported prevalence in Asians when we investigated its prevalence using multiplanar images. The prevalence of AD in the axial and sagittal planes was not negligible. We therefore suggest that it is important to add axial and sagittal planes' data when investigating the prevalence of AD.


Asunto(s)
Acetábulo/diagnóstico por imagen , Pueblo Asiatico , Luxación de la Cadera/diagnóstico por imagen , Luxación de la Cadera/epidemiología , Tomografía Computarizada por Rayos X/normas , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Estudios Retrospectivos
6.
J Orthop Sci ; 22(1): 105-111, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27720511

RESUMEN

BACKGROUND: Femoroacetabular impingement (FAI) is thought to be associated with hip osteoarthritis. We investigated the prevalences of radiologic deformities of the pincer, cam, and their combinations in Japanese hip joints using computed tomography (CT) according to the Japanese Hip Society diagnostic guideline for FAI. METHODS: Multi-slice CT images were evaluated. Pincer deformities were defined as: type 1: center-edge angle (CE) ≥40°; type 2: CE ≥ 30° and acetabular roof obliquity ≤0°; type 3: CE ≥ 25° and retroverted acetabulum. Cam deformities were defined as: type 1: CE ≥ 25°, α-angle ≥55°, and head-neck offset ratio <0.14; type 2: CE ≥ 25°, α-angle ≥55°, and herniation pit positive; type 3: CE ≥ 25°, α-angle ≥55°, and pistol grip deformity positive. RESULTS: We studied 128 hips. Pincer was detected in 35.9% (type 1, 12.5%; type 2, 18.0%; type 3, 13.3%). Cam was detected in 24.2% (type 1, 23.4%; type 2, 7.8%; type 3, 10.9%). Combined deformities were detected in 10.2%. Type 3 pincer/type 1 cam was the most frequent combined deformity compared with all combined deformities. All of the cam deformities, total combined deformities, and all radiological FAIs appeared significantly more often in men. CONCLUSIONS: When we used this guideline to diagnose FAI in a Japanese population, radiological FAI was common, and pincer deformities were more common than cam deformities. The most frequent seen pincer, cam, and combined deformities was type 2 pincer, type 1 cam, and the combination of type 3 pincer/type 1 cam, respectively.


Asunto(s)
Acetábulo/anomalías , Pinzamiento Femoroacetabular/diagnóstico por imagen , Pinzamiento Femoroacetabular/epidemiología , Imagenología Tridimensional , Tomografía Computarizada Multidetector/métodos , Guías de Práctica Clínica como Asunto , Acetábulo/diagnóstico por imagen , Adulto , Distribución por Edad , Anciano , Anciano de 80 o más Años , Femenino , Pinzamiento Femoroacetabular/fisiopatología , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/fisiopatología , Humanos , Japón/epidemiología , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Osteoartritis de la Cadera/diagnóstico por imagen , Osteoartritis de la Cadera/epidemiología , Osteoartritis de la Cadera/fisiopatología , Examen Físico/métodos , Prevalencia , Pronóstico , Rango del Movimiento Articular/fisiología , Medición de Riesgo , Índice de Severidad de la Enfermedad , Distribución por Sexo , Sociedades Médicas/normas
7.
JBJS Case Connect ; 4(4): e105, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-29252773

RESUMEN

CASE: Mitochondrial myopathy comprises heterogeneous neuromuscular disorders caused by mitochondrial dysfunction. Acute exacerbation of mitochondrial myopathy infrequently occurs sequentially after perioperative stress. We present an unusual case of a late-emerging and lethal exacerbation of mitochondrial myopathy after total hip arthroplasty. Despite special attention paid to perioperative control, the patient's condition drastically deteriorated on postoperative day thirteen, and she died later as a result of cardiomyopathy. CONCLUSION: When performing surgery on a patient with mitochondrial myopathy, the merits of surgery must always surpass the possible grave risk of this condition.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...