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1.
Osteoporos Int ; 26(6): 1759-71, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25736166

RESUMO

UNLABELLED: In this study, we characterized longitudinal changes of volumetric bone mineral density and cortical and trabecular microstructure at the distal radius using HR-pQCT in female systemic lupus erythematosus (SLE) patients on long-term glucocorticoids. Cortical thinning and increased cortical porosity are the major features of longitudinal microstructural deterioration in SLE patients. INTRODUCTION: The study aims to characterize longitudinal changes of volumetric bone mineral density (vBMD) and bone microstructure at distal radius in female systemic lupus erythematosus (SLE) patients on long-term glucocorticoids. METHODS: This 2-year case-control study consisted of 166 premenopausal subjects (75 SLE patients and 91 controls) and 79 postmenopausal subjects (44 SLE patients and 35 controls). We obtained areal BMD (aBMD) by dual-energy X-ray absorptiometry at multiple skeletal sites and indices of vBMD and microstructure at distal radius by high-resolution peripheral quantitative computed tomography (HR-pQCT) at baseline, 12 and 24 months. RESULTS: In either premenopausal or postmenopausal subjects, changes in aBMD did not differ between patients and controls except that decrease in aBMD at total hip at 24 months in premenopausal patients was significantly higher. In premenopausal subjects, decrease in cortical area (-0.51 vs. -0.06 %, p = 0.039) and thickness (-0.63 vs. 0.02 %, p = 0.031) and increase in cortical porosity (21.7 vs. 7.16 %, p = 0.030) over study period were significantly larger in patients after adjustment of age and body mass index. Decreased in trabecular vBMD was significantly less (-0.63 vs. -2.32 %, p = 0.001) with trabecular microstructure better maintained in patients. In postmenopausal subjects, decrease in cortical vBMD (-2.66 vs. -1.56 %, p = 0.039) and increase in cortical porosity (41.6 vs. 16.3 %, p = 0.021) were significantly higher in patients, and there was no group-wise difference in change of trabecular microstructure. CONCLUSION: Longitudinal microstructural deterioration in SLE is characterized by cortical thinning and increased cortical porosity. Cortical bone is an important source of bone loss in SLE patients on glucocorticoids.


Assuntos
Glucocorticoides/efeitos adversos , Lúpus Eritematoso Sistêmico/complicações , Osteoporose/etiologia , Absorciometria de Fóton/métodos , Adulto , Densidade Óssea/efeitos dos fármacos , Densidade Óssea/fisiologia , Estudos de Casos e Controles , Progressão da Doença , Feminino , Glucocorticoides/farmacologia , Glucocorticoides/uso terapêutico , Humanos , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Lúpus Eritematoso Sistêmico/fisiopatologia , Pessoa de Meia-Idade , Osteoporose/patologia , Osteoporose/fisiopatologia , Osteoporose Pós-Menopausa/etiologia , Osteoporose Pós-Menopausa/patologia , Osteoporose Pós-Menopausa/fisiopatologia , Porosidade , Pré-Menopausa/fisiologia , Rádio (Anatomia)/efeitos dos fármacos , Rádio (Anatomia)/patologia , Rádio (Anatomia)/fisiopatologia , Tomografia Computadorizada por Raios X/métodos
2.
Osteoporos Int ; 26(1): 261-72, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25160570

RESUMO

UNLABELLED: We investigated the densitometric and microstructural features of the distal radius in psoriatic arthritis (PsA) patients using high-resolution peripheral quantitative computed tomography. PsA patients have unique bone microstructural deficits, manifested as lower cortical bone density and higher cortical porosity, which are associated with a propensity to bone fragility. INTRODUCTION: The aim of this study was to investigate the densitometric, geometric, microstructural, and biomechanical features of the distal radius in psoriatic arthritis (PsA) patients. METHODS: This study cohort consisted of 53 PsA patients (24 males and 29 females), with an average age of 53.1 years and 53 gender- and age-matched controls. Areal bone mineral density (aBMD) of the hip, lumbar spine, and ultradistal radius was measured by dual-energy X-ray absorptiometry. High-resolution peripheral quantitative computed tomography (HR-pQCT) was performed at the distal radius to obtain measures of volumetric BMD (vBMD), microstructure, and derived biomechanical indices. RESULTS: There were no significant between-group differences in aBMD at the femoral neck, total hip, and ultradistal radius, while aBMD at the lumbar spine was significantly higher in patients. The only indices indicating compromised bone quality in PsA patients were related to cortical bone quality. Cortical vBMD were -3.8% significantly lower, while cortical pore volume, porosity index, and pore diameter were 108, 79.5, and 8.6%, respectively, significantly higher in patients. Cortical stress was marginally lower (-1.3%, p = 0.077) in patients with stress significantly more unevenly distributed (4.9%, p = 0.035). Endocortical perimeter and cortical pore volume were significantly higher in patients with vertebral fracture. Deficits in cortical bone quality were associated with indices of disease activity/severity and were more prominent in patients with type 2 diabetes mellitus or hypertension. CONCLUSIONS: There is an intertwined relationship between chronic inflammation, cardiovascular risk factors, and bone loss in PsA. PsA patients seem to have unique bone microstructural deficits which are associated with a propensity to bone fragility.


Assuntos
Artrite Psoriásica/fisiopatologia , Densidade Óssea/fisiologia , Inflamação/fisiopatologia , Osteoporose/etiologia , Rádio (Anatomia)/fisiopatologia , Absorciometria de Fóton/métodos , Adulto , Artrite Psoriásica/complicações , Estudos de Casos e Controles , Estudos Transversais , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Humanos , Inflamação/complicações , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , Osteoporose/fisiopatologia , Fraturas por Osteoporose/etiologia , Fraturas por Osteoporose/fisiopatologia , Fatores de Risco , Tomografia Computadorizada por Raios X/métodos
3.
Lupus ; 23(9): 854-61, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24644010

RESUMO

OBJECTIVE: The objective of this paper is to investigate the incidence of both non-vertebral and vertebral fracture in female patients with systemic lupus erythematosus (SLE) and to identify risk factors for incident fracture. METHODS: In a five-year prospective study of 127 female Chinese SLE patients with an average age of 46.9 years (SD: 10.1 years), information on potential risk factors, including demographics, clinical data and bone mineral density (BMD) at lumbar spine and hip by dual-energy X-ray absorptiometry was collected at baseline. At follow-up, participants reported incident non-vertebral fracture during the study period. Semi-quantitative analysis was used to determine incident vertebral fracture on lateral thoracic and lumbar radiographs, defined as any vertebral body graded normal at baseline and at least mildly deformed (20%-25% reduction or more in any vertebral height) at follow-up. RESULTS: Nine incident non-vertebral fractures occurred in eight patients during the study period. Six patients had one or more incident vertebral fractures. The incidence of non-vertebral and vertebral fracture was 1.26 and 0.94 per 100 patient-years, respectively. In multivariate logistic analyses, independent variables associated with incident non-vertebral fracture were duration of glucocorticoid use and prevalent lumbar spine osteoporosis, while risk factors associated with incident vertebral fracture were higher organ damage and prevalent lumbar spine osteoporosis. CONCLUSIONS: The incidence of fracture in SLE patients is lower than the prevalence reported in cross-sectional studies. Lumbar spine BMD appears to have a stronger relationship with incident fracture than hip BMD. This warrants further investigation regarding the optimal site of BMD measurement when predicting fracture risk in SLE patients.


Assuntos
Fraturas Ósseas/epidemiologia , Fraturas Ósseas/etiologia , Lúpus Eritematoso Sistêmico/complicações , Adulto , Idoso , Povo Asiático , Densidade Óssea , Estudos de Coortes , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Fatores de Risco , Fraturas da Coluna Vertebral/epidemiologia , Fraturas da Coluna Vertebral/etiologia , Fatores de Tempo , Adulto Jovem
4.
Radiother Oncol ; 104(3): 317-23, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22551564

RESUMO

BACKGROUND AND PURPOSE: Significant tumor shrinkage and weight loss may occur during Intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC). This study aims to evaluate the dosimetric effect of volumetric changes on target volumes and organs at risk (OARs) during IMRT, using reassessment of computed tomography (CT) and magnetic resonance imaging (MRI). MATERIAL AND METHODS: Nineteen loco-regionally advanced NPC patients treated with IMRT were recruited prospectively. Repeat planning CT and MRI were acquired at 30 and 50 Gy intervals. Recontouring of target volumes and OARs was based on the fused CT-MRI images. Hybrid plans with recontouring were generated. The assessment of volumetric and dosimetric changes was performed by comparing the hybrid plans with the original plan. RESULTS: There was volume reduction of target volumes and parotid glands over the course of IMRT. Relative to the original plan, the hybrid plans demonstrated significantly higher dose to most of target volumes with greater dose inhomogeneity, higher maximum doses to the spinal cord and brainstem, and higher median doses to the parotid glands. CONCLUSIONS: Replanning with repeat CT and MRI scans at 30 Gy is essential to keep a satisfactory dose to the target volumes and avoid overdosing the OARs.


Assuntos
Neoplasias Nasofaríngeas/radioterapia , Radioterapia de Intensidade Modulada , Adulto , Idoso , Carcinoma , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/patologia , Estudos Prospectivos , Dosagem Radioterapêutica , Radioterapia de Intensidade Modulada/efeitos adversos , Tomografia Computadorizada por Raios X , Carga Tumoral , Redução de Peso
5.
Asia Pac J Public Health ; 16 Suppl: S17-21, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15828505

RESUMO

A district based needs assessment as conducted over the past year to uderstand the health problems and the health education needs of the students in Tai Po district, Hong ong. 6879 primary one to primary six students from eighteen rimary schools, participating in a district based Health Promoting Schools Project in Hong Kong, were invited to complete a self-administrated questionnaire which was partly adapted from the Centre for Diseases and Control (CDC)'s Youth Risk Behaviour Surveillance Survey. The results presented a holistic picture of the health and needs of primary students with respect to their general health status, mental health, body weight and dietary behaviour, exercise, preventive health care, tobacco use, alcohol and other drug use, school environment and school health education. It provides baseline information for the project to prioritize the problems and strategically plan health promotion 'programmes with reference to the concept of Health Promoting Schools by the World Health Organization.


Assuntos
Educação em Saúde/métodos , Promoção da Saúde/métodos , Avaliação das Necessidades , Instituições Acadêmicas , Adolescente , Criança , Feminino , Comportamentos Relacionados com a Saúde , Conhecimentos, Atitudes e Prática em Saúde , Nível de Saúde , Hong Kong , Humanos , Masculino , Fenômenos Fisiológicos da Nutrição , Inquéritos e Questionários
6.
Clin Oncol (R Coll Radiol) ; 15(6): 329-36, 2003 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-14524486

RESUMO

The clinical features, management and outcome of 1348 patients diagnosed with differentiated thyroid carcinoma in Queen Elizabeth Hospital, Hong Kong, were analysed according to the period of diagnosis: A (before 1980), B (1981-1990) and C (1991-2000). As time advanced, ratio of papillary carcinoma (PTC) to follicular carcinoma (FTC) increased (A:B:C = 1.6: 3.1: 7.2). The mean size of the primary tumour decreased (A:B:C = 3.5 cm: 2.8 cm: 2.5 cm), with a greater percentage of microcarcinoma of 1 cm or less (A:B:C = 5.1%: 16.1%: 21.7%). At presentation, the incidence of lymph-node metastasis decreased (A:B:C = 32.7%: 31.6%: 24.8%) and that of distant metastasis decreased (A:B:C = 9%: 6.1%: 5.3%). Bilateral surgical resection was more commonly used (A:B:C = 62.8%: 89.1%: 94.8%) than lobectomy (A:B:C = 26.3%: 2.8%: 1.8%). Radiation treatment, radioactive iodine (131I; RAI) and external radiotherapy (EXT), was more commonly used (A:B:C = 53.2%: 74.7%: 85.1%). RAI was used in 84.3% (A:B:C = 50%: 71.2%: 84.3%) and EXT in 14.5% of patients in the past decade (A:B:C = 10.9%: 8.7%: 14.5%). The proportion of patients who adopted a bilateral surgery and RAI treatment increased gradually with time (A:B:C = 33%: 68%: 83.8%). The 5-year cause-specific survival (A:B:C = 90.2%: 93.7%: 95.7%), locoregional failure-free survival (A:B:C = 72.6%: 82.9%: 91.6%) and distant metastasis failure-free survival (A:B:C = 84.5%: 89.1%: 92.6%) were improved. However, the period of diagnosis was not found to be an important explanatory variable (i.e. P > 0.05) in Cox regression after adjusting for other factors, indicating that the improvement was probably related to the temporal trend of other factors: presentation at earlier stage, increased ratio of PTC:FTC and more aggressive management by bilateral surgery and radiation therapy.


Assuntos
Carcinoma Papilar, Variante Folicular/diagnóstico , Carcinoma Papilar, Variante Folicular/terapia , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/terapia , Adulto , Distribuição por Idade , Carcinoma Papilar, Variante Folicular/epidemiologia , Carcinoma Papilar, Variante Folicular/secundário , Intervalo Livre de Doença , Feminino , Hong Kong/epidemiologia , Humanos , Incidência , Excisão de Linfonodo/estatística & dados numéricos , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/epidemiologia , Estadiamento de Neoplasias , Estudos Prospectivos , Distribuição por Sexo , Neoplasias da Glândula Tireoide/epidemiologia , Tireoidectomia/estatística & dados numéricos , Resultado do Tratamento
7.
Osteoporos Int ; 13(12): 962-70, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12459939

RESUMO

The current study was designed to investigate the rate of bone loss in distal radius and its association with baseline volumetric bone mineral density (BMD) and years since menopause (YSM) in peri- and postmenopausal women using precise and multislice peripheral quantitative computed tomography (pQCT; Densiscan 2000). Two hundred and five healthy Hong Kong Chinese perimenopausal ( n = 26) and postmenopausal ( n = 179) women within 10 years of the onset of menopause were recruited. Anthropometric parameters and menstrual status were also measured. The linear regression model derived from the baseline volumetric BMD revealed a significant and slightly better correlation with YSM than age, with a YSM-related annual decline of 2.56%, 1.82% and 0.65% in trabecular BMD (tBMD), integral BMD (iBMD) and cortical BMD (cBMD), respectively. Follow-up measurements after a time interval of 12 months showed that the rate of bone loss was higher than the annual decline in BMD calculated from the baseline BMD, with decreases of 2.89%, 2.16% 0.91% in tBMD, iBMD and cBMD, respectively. Baseline BMD was associated with age or YSM ( r ranges from -0.283 to -0.502; p<0.001 in all cases), but no relationship was found between annual rate of bone loss and age or YSM. The rate of bone loss did not correlate with baseline volumetric BMD values or YSM after dividing the subjects into fast bone losers (with annual tBMD loss > or =3%), normal bone losers (with annual tBMD loss > or = 1% but <3%) or slow bone losers (with annual tBMD loss <1%). The rate of bone loss was greater in both trabecular and cortical bone of postmenopausal women within the first 3 menopausal years but was only significant in the iBMD as compared with perimenopausal and postmenopausal women over 7 years after onset of menopause. The percentage distribution of slow and fast bone losers was not found to be associated with YSM. As a total of only 4 fracture cases were documented, the study could not provide conclusive information on whether perimenopausal and early postmenopausal baseline volumetric BMD or rate of bone loss determines the development of osteoporosis or fracture occurrence.


Assuntos
Densidade Óssea , Osteoporose Pós-Menopausa/fisiopatologia , Adulto , Envelhecimento/fisiologia , Antropometria/métodos , Climatério/fisiologia , Progressão da Doença , Feminino , Seguimentos , Humanos , Modelos Lineares , Menstruação , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/diagnóstico por imagem , Pós-Menopausa/fisiologia , Rádio (Anatomia)/diagnóstico por imagem , Rádio (Anatomia)/fisiopatologia , Fatores de Tempo , Tomografia Computadorizada por Raios X
8.
Ann Oncol ; 13(8): 1252-8, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12181249

RESUMO

BACKGROUND: To evaluate the efficacy and toxicity of combination gemcitabine plus cisplatin (GC) chemotherapy in metastatic or recurrent nasopharyngeal carcinoma (NPC). PATIENTS AND METHODS: Forty-four patients of Chinese ethnicity with metastatic or recurrent NPC received ambulatory GC chemotherapy every 28 days (gemcitabine 1000 mg/m(2) days 1, 8 and 15; cisplatin 50 mg/m(2) days 1 and 8). There were 40 male and four female patients with a mean age of 47.4 years. More than half (54.5%) of the patients had received either prior platinum-based chemotherapy and/or radiotherapy to target lesions. RESULTS: There were nine complete responses and 23 partial responses in the 44 patients, achieving an overall response rate of 73% (78% for the 41 assessable patients). The mean duration of response was 5.3 months. Improved subjective symptom-control scores were found in 78% of patients with pre-existing symptoms, while 64% of patients experienced improved general well-being scores. Toxicity was mainly hematological: grade III/IV anemia, granulocytopenia and thrombocytopenia were found in 11, 37 and 16% of cycles, respectively. With a median follow-up of 17.2 months, 62% survived 1 year while 36% were alive and progression free. CONCLUSIONS: Gemcitabine plus cisplatin chemotherapy offers a satisfactory overall response rate, subjective patient improvement and safety profile for metastatic and recurrent NPC.


Assuntos
Adenocarcinoma/tratamento farmacológico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Desoxicitidina/análogos & derivados , Neoplasias Nasofaríngeas/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Adenocarcinoma/secundário , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Escamosas/secundário , Cisplatino/administração & dosagem , Desoxicitidina/administração & dosagem , Feminino , Doenças Hematológicas/induzido quimicamente , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/patologia , Taxa de Sobrevida , Resultado do Tratamento , Gencitabina
9.
Calcif Tissue Int ; 67(1): 29-36, 2000 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-10908409

RESUMO

The aim of this cross-sectional study was to use a newly available precise and multislice pQCT (Densiscan 2000) for establishing reference data of volumetric bone mineral density (vBMD) of the distal radius. vBMD of the nondominant wrist was measured in 118 healthy Hong Kong Chinese women aged 41-60. Anthropometric parameters, menstrual status, and handgrip strength were also measured. Results showed that there was a significant age-related decline in trabecular BMD (tBMD), integral BMD (iBMD), and cortical BMD (cBMD), with correlation coefficients ranging from -0.401 to -0.547 (P < 0.001). The annual decline of vBMD was 2.22%, 1.79%, and 0.88% in tBMD, iBMD, and cBMD, respectively. When subjects were divided into premenopausal and postmenopausal groups, we found an age-related decline in tBMD and iBMD, but not in cBMD in both groups. The vBMD values interpreted in mg/cm3 in premenopausal women were 238.4 +/- 57.2 in tBMD, 604.6 +/- 82.9 in iBMD, 1415.5 +/- 129.9 in cBMD, and declined significantly (all P < 0.001) to 193.7 +/-54.7 in tBMD, 500.0 +/- 90.3 in iBMD, and 1306.7 +/- 153.5 in cBMD in the postmenopausal women. On average, 16.7% of the subjects showed their vBMDs to be below-1 SD and only 1.7% of them lower than -2 SD. Linear regression showed that the annual decline of vBMD was faster in postmenopausal women with 2.42% in tBMD, 1.90% in iBMD, and 0.88% in cBMD compared with 1.91% in tBMD, 0.98% in iBMD, and 0.55% in cBMD in the premenopausal women. After adjustment for age, only the iBMD with dominant trabecular elements showed a significantly accelerated decrease after the onset of menopause (P = 0.008). Weak or no association was found among vBMDs with anthropometric parameters, years since menopause, or handgrip strength. In conclusion, we found a significant age-related decline of vBMDs in Hong Kong Chinese women aged 41-60 years, characterized by the early reduction of metabolically active trabecular bone after entering the fourth decade of life, with an accelerated decline after the onset of menopause.


Assuntos
Envelhecimento/fisiologia , Povo Asiático , Densidade Óssea , Rádio (Anatomia)/fisiologia , Adulto , Estudos Transversais , Feminino , Hong Kong , Humanos , Menstruação/fisiologia , Pessoa de Meia-Idade , Pós-Menopausa , Pré-Menopausa , Radiografia , Rádio (Anatomia)/diagnóstico por imagem
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