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1.
Front Sports Act Living ; 6: 1388194, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38783866

RESUMO

Objective: To examine the effectiveness of a specially designed video-based exercise program in promoting physical and balance performance in people with intellectual disability. Methods: This study was a multicenter controlled trial. Participants with intellectual disability were divided into exercise group and control group by cluster sampling. The participants in the exercise group received 1 h exercise training sessions twice a week for 8 weeks, and the controls continued their usual care without exercise training. The exercises were specially designed to match the physical ability level of the participants classified as high and low, and a third group called "special" was designed for those wheelchair-bound persons with limited mobility. Elements of light-tempo music and animation were introduced in the videos to motivate the participants. Recording the exercises in video format makes it easier for the class instructors and participants to perform the exercises together, and ensure consistency across different exercise groups conducted in different centers. Each participant underwent the pre- and post-intervention assessment including 30-s chair stand repetitions, five-time chair stand duration, 4-m comfortable walk time, standing static balance level, 6-min walk test, and short physical performance battery score. These variables were compared within each group at pre- and post-intervention stages, and they were also compared between the two groups. Results: A total of 180 participants were enrolled in 16 subcenters, including 160 participants in the exercise group and 20 participants in the control group. After 8 weeks of exercise training, there were significant improvements in their physical performance including 30-s chair stand repetitions and five-time chair stand duration, 4-m comfortable walk time and also 6-min walk test, within the exercise group (all P < 0.05). Approximately 39% of the participants in the exercise group also showed significant improvement in standing static balance level. No significant differences were found when compared with the control group participants who did not have any regular exercise participation. Conclusion: A specially designed video-based exercise program has demonstrated some positive effects on physical and balance performance after 8 weeks of training among adults with intellectual disability.

2.
J Exerc Sci Fit ; 22(4): 278-287, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38618555

RESUMO

Background: /Objective. An explosion in global obesity epidemic poses threats to the healthcare system by provoking risks of many debilitating diseases, including cognitive dysfunction. Physical activity has been shown to alleviate the deleterious effects of obesity-associated cognitive deficits across the lifespan. Given the strong neuroprotective role of brain-derived neurotrophic factor (BDNF) and exercise training as a known modulator for its elevation, this systematic review sought to examine the strength of the association between exercise and BDNF levels in healthy people with overweight and obesity. Methods: Six electronic databases (PubMed, MEDLINE, EMBASE, Web of Science, Ovid Nursing Database, and SPORTDiscus) were searched from their inceptions through December 2022. The primary outcome of interest was BDNF levels. Interventional studies (randomized and quasi-experimental) with English full text available were included. Risk of bias of the included studies was assessed using the Physiotherapy Evidence Database Scale. Data were extracted for meta-analyses by random-effects models. Results: Thirteen studies (n = 750), of which 69.2% (9/13) had low risk of bias, were included. In the meta-analysis, exercise interventions had no significant effect on resting BDNF levels (standardized mean difference: -0.30, 95% CI -0.80 to 0.21, P = 0.25). Subgroup analyses also indicated no effects of age and types of control groups being compared on moderating the association. Conclusion: To further inform the role of BDNF in obesity-related cognitive functioning, rigorous studies with larger samples of participants and raw data available were imperatively deserved.

3.
Quant Imaging Med Surg ; 12(3): 2090-2105, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35284274

RESUMO

For the MrOS (Hong Kong) and MsOS (Hong Kong) baseline (BL) studies, community-dwelling 2,000 Chinese men (mean age: 72.3 years) and 2,000 Chinese women (mean age: 72.5 years) were recruited from 2001 to 2003. These two studies have spanned two decades till now. This review summarizes our spine radiograph results. Senile and post-menopausal osteoporosis were associated with intervertebral disc volume reduction; and in women, menopause accelerates disc degeneration. Elderly women's osteoporotic vertebral fracture (OVF) prevalence was double of that of elderly men. For year-4 follow-up (FU), male participants with BL OVF had little increased risk for further OVF. In our study comparing OVF rates in age-matched Hong Kong Chinese women and Italian Caucasian women (mean age: 74.1 years), endplate and/or cortex fracture (ECF) prevalence was 26% for Chinese and 47% for Italian. OVF with ≥40% vertebral height loss was recorded among 9.5% of the Chinese subjects while among 26% of the Italian subjects. OVFs in Italian subjects were more likely to be multiple and generally severer. Clinical spine fractures were recorded 133 cases/100,000 person-years in MrOS (Hong Kong) participants and 273 cases/100,000 person-years in MsOS (Hong Kong) participants. Literature review suggests the clinical vertebral fracture rates among elderly Hong Kong Chinese subjects are approximately half of those of American, Australian, and Canadian subjects. Data synthesis suggests elderly Caucasians have a higher degenerative spondylolisthesis prevalence, being approximately 70% higher than that of elderly Hong Kong Chinese. Literature review of other authors' publications shows, compared with Caucasians, Chinese have a much lower incident rate of back pain. We conclude that elderly Chinese have a generally healthier spine relative to elderly Caucasians.

4.
Pediatr Neonatol ; 62(6): 620-627, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34330685

RESUMO

BACKGROUND: Understanding trauma epidemiology is essential in formulating region-specific strategies for injury prevention. Our study aimed to evaluate the characteristics and clinical outcomes of critical pediatric trauma requiring intensive care in Hong Kong. METHODS: A retrospective analysis was performed on pediatric patients who were injured and admitted to the pediatric intensive care unit (PICU), Queen Elizabeth Hospital, Hong Kong between 2014 and 2018. Clinical features of patients who sustained injuries before and after 2 years old were compared. RESULTS: 141 patients were admitted to the PICU due to trauma during the study period. Most patients sustained injuries due to fall (48.2%) or road traffic injuries (34.0%), with the latter more common in older patients. Two (1.4%) patients died due to the trauma. The majority (95.0%) of the survivors had good recovery assessed by Glasgow Outcome Scale. Patients younger than 2 years old were mostly injured at home due to fall while left unattended. Children in this age group were more likely to receive interventions, including mechanical ventilation (OR 2.61; 95% CI 1.15-5.95), anti-epileptic medications (OR 2.61; 95% CI 1.17-5.83), blood transfusion (OR 5.37; 95% CI 2.29-12.60) and inotropic support (OR 4.08; 95% CI 1.31-12.70), and require longer hospitalization (PICU stay 2.5 vs. 1.5 days, p = 0.011; hospital stay 10.9 vs. 6.9 days, p = 0.012). CONCLUSION: Fall injuries and road traffic injuries were common etiologies of critical pediatric trauma in Hong Kong. Patients younger than 2 years old had worse clinical outcomes. Parental education on home safety and importance of close supervision should be emphasized in this age group.


Assuntos
Unidades de Terapia Intensiva Pediátrica , Centros de Traumatologia , Idoso , Criança , Pré-Escolar , Hong Kong/epidemiologia , Humanos , Tempo de Internação , Estudos Retrospectivos
5.
J Occup Health ; 63(1): e12255, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34288276

RESUMO

OBJECTIVES: Cases of injury on duty (IOD) are common in Hong Kong, but literature on this group of patients is limited. This study aims to describe local IOD cases' epidemiological characteristics and identify factors affecting return to work (RTW) outcomes. METHODS: This is a retrospective epidemiological study of IOD patients in the orthopedic and traumatology center of Yan Chai Hospital in 2016, using the hospital's electronic clinical record analysis and reporting system; 323 out of the 10 730 patients (M:F = 206:117; mean age 46.9 ± 11.3) were included. Data on demographics, the injury episode, administrative procedures, treatment and rehabilitation were collected. Outcomes were measured by "RTW" and "time to RTW from injury." RESULTS: Around 80% of patients had a successful RTW and the mean time to RTW was 10.6 ± 9.0 months. Patients who were female, divorced or widowed and living alone in a public rental flat were less likely to RTW. Psychiatric consultations (OR 13.70, P < .001), legal disputes (OR 8.20, P < .001) and more than 5 months of waiting time for physiotherapy (OR 3.89, P = .002) were the strongest among the numerous risk factors for non-RTW. An increase in one visit to the general outpatient clinic and the presence of legal disputes had lengthened the time to RTW by 4.8 days (P < .001) and 18.0 months (P < .001), respectively. CONCLUSIONS: Several demographic, psychosocial and administrative factors were negatively associated with RTW in the local population. Recommendations were made for healthcare providers and policymakers accordingly.


Assuntos
Saúde Ocupacional/estatística & dados numéricos , Traumatismos Ocupacionais/reabilitação , Ortopedia/estatística & dados numéricos , Retorno ao Trabalho/estatística & dados numéricos , Traumatologia/estatística & dados numéricos , Adulto , Feminino , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Traumatismos Ocupacionais/psicologia , Razão de Chances , Estudos Retrospectivos , Retorno ao Trabalho/psicologia , Fatores de Risco
6.
J Orthop Surg Res ; 16(1): 282, 2021 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-33906695

RESUMO

BACKGROUND: Osteoarthritis of the knee is a common degenerative joint disorder in our ageing population. A combination of thermal therapy with a self-management exercise have shown a positive effect in the management of osteoarthritis of the knee. This study aimed to compare the effectiveness of topical heat pack versus focal application of heat therapy at the acupressure points in the treatment of osteoarthritis of the knee. METHODS: A randomized controlled trial was conducted in 76 patients with osteoarthritis of the knee, diagnosed by an experienced orthopedic surgeon. Following inclusion and exclusion selection, patients were randomly allocated to group 1 (Heat pack) or group 2 (Thermal gun). All patients received 30 min of treatment in each session, twice a week for 4 weeks. They also received an education program and taught home knee exercises. Outcome measurements were the visual analog scale (VAS) for pain intensity, muscle power, knee ROM, WOMAC and SF-12v2. RESULTS: In the Thermal gun group, function and total scores (WOMAC) and Physical Composite Scale (SF-12v2) were significantly improved after 8 sessions. Quadriceps strength was significantly improved after 8 weeks (from 4.42 to 4.63; p = 0.02). In the Heat pack group, flexion was significantly improved after 8 sessions (p = 0.02). Mean VAS scores after Heat pack treatment was consistently better (lower) than mean VAS scores after Thermal gun treatment. CONCLUSION: The combination of focal thermal therapy at acupressure points is a viable conservative treatment in osteoarthritis of the knee. The pressure at the acupressure points has a synergistic benefit than topical thermal therapy alone. TRIAL REGISTRATION: ClinicalTrials.gov , NCT04735029 Date of registration: February 2, 2021 (Retrospectively registered).


Assuntos
Acupressão , Pontos de Acupuntura , Hipertermia Induzida/métodos , Osteoartrite do Joelho/terapia , Idoso , Terapia por Exercício/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento
7.
Biochem J ; 477(18): 3599-3612, 2020 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-32869839

RESUMO

Among the major challenges in the development of biopharmaceuticals are structural heterogeneity and aggregation. The development of a successful therapeutic monoclonal antibody (mAb) requires both a highly active and also stable molecule. Whilst a range of experimental (biophysical) approaches exist to track changes in stability of proteins, routine prediction of stability remains challenging. The fluorescence red edge excitation shift (REES) phenomenon is sensitive to a range of changes in protein structure. Based on recent work, we have found that quantifying the REES effect is extremely sensitive to changes in protein conformational state and dynamics. Given the extreme sensitivity, potentially this tool could provide a 'fingerprint' of the structure and stability of a protein. Such a tool would be useful in the discovery and development of biopharamceuticals and so we have explored our hypothesis with a panel of therapeutic mAbs. We demonstrate that the quantified REES data show remarkable sensitivity, being able to discern between structurally identical antibodies and showing sensitivity to unfolding and aggregation. The approach works across a broad concentration range (µg-mg/ml) and is highly consistent. We show that the approach can be applied alongside traditional characterisation testing within the context of a forced degradation study (FDS). Most importantly, we demonstrate the approach is able to predict the stability of mAbs both in the short (hours), medium (days) and long-term (months). The quantified REES data will find immediate use in the biopharmaceutical industry in quality assurance, formulation and development. The approach benefits from low technical complexity, is rapid and uses instrumentation which exists in most biochemistry laboratories without modification.


Assuntos
Anticorpos Monoclonais/química , Conformação Proteica , Estabilidade Proteica , Espectrometria de Fluorescência
8.
J Clin Densitom ; 22(3): 409-419, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-29307693

RESUMO

This study aims to evaluate endplate/cortex fracture (ECF)-based method for detecting osteoporotic vertebral fracture (VF) in elderly Chinese population (age ≥ 65 years). The radiographs of 1954 elderly Chinese men (mean: 72.3 years) and 1953 elderly Chinese women (mean: 72.5 years) were evaluated according to Genant's morphometrical vertebral deformity (VD) severity criteria, as well as identified VF according to ECF without necessary requirement of VD. According to ECF, grade-1, -2, and -3 VF prevalence was 1.89%, 1.74%, and 2.25% in men, and 3.33%, 3.07%, and 5.89% in women, respectively. In men and women, 15.7% (35 of 223) and 34.5% (48 of 139) of vertebrae with VD grade-1 deformity were ECF(+, with fracture), respectively. In men and women, 89.7% (35 of 39) and 66.7% (48 of 72) of vertebrae with ECF grade-1 fracture had VD grade-1 deformity. For grade-1 change, ECF(+) subjects tended to have a lower BMD than the VD(+) subjects. In subjects with VD grade-2 deformity, those who were also EC (+) tended to have a lower BMD than those were ECF(-). In all grades, VD(-) and ECF(-) subjects tended to have highest BMD, whereas VD(+) and ECF(+) subjects tended to have lowest BMD. ECF may be more specific for assessing mild VF than the criteria based on vertebral deformity.


Assuntos
Algoritmos , Vértebras Lombares/diagnóstico por imagem , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas da Coluna Vertebral/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , China/epidemiologia , Feminino , Hong Kong/epidemiologia , Humanos , Vértebras Lombares/lesões , Masculino , Fraturas por Osteoporose/epidemiologia , Prevalência , Radiografia , Fraturas da Coluna Vertebral/epidemiologia
9.
Arch Osteoporos ; 13(1): 95, 2018 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-30194552

RESUMO

We compared global sagittal alignment and quality of life in osteoporotic patients with and without vertebral compression fracture (VCF) and determined its relationship with VCF severity. The findings revealed osteoporotic patients with VCF showed decreased quality of life and worse global sagittal alignment, which was significantly associated with VCF severity. INTRODUCTION: The aim of this study was to compare the global sagittal alignment and quality of life in elderly osteoporotic patients with and without vertebral compression fracture (VCF), and to investigate the relationship between global sagittal alignment and severity of VCF. METHODS: A consecutive series of 72 female patients with osteoporosis aged over 60 years and 31 age-matched females without osteoporosis were prospectively enrolled. The patients were divided into VCF and non-VCF group. Patient's clinical demography, nature of VCF, and bone mineral density (BMD) were also recorded. Spinal deformity index was used to evaluate severity of VCF. EOS® biplanar imaging system was then used to evaluate global sagittal parameters: T1 pelvic angle (TPA) and global sagittal angle (GSA). In addition, quality of life was assessed with self-reported questionnaires: the Oswestry Disability Index (ODI) and Short-form 12 (SF-12). RESULTS: Osteoporotic patients and controls were found to be significantly different in terms of TPA, GSA, and BMD. And in patients with VCF, they were found to have significantly higher TPA and GSA. TPA and GSA were significantly correlated with SF-12 and ODI. The number of VCF and SDI significantly correlated with global sagittal alignment. Using regression analysis, parameters significantly associated with abnormal global alignment were the number of VCF (OR = 1.13) and SDI (OR = 1.84). CONCLUSION: Osteoporotic patients with VCF showed worse global sagittal alignment and decreased quality of life. The number and severity of VCF had a negative influence on global sagittal balance, which indicates that poorer sagittal global alignment may imply worse quality of life and more severe VCF.


Assuntos
Fraturas por Compressão/fisiopatologia , Osteoporose/fisiopatologia , Índice de Gravidade de Doença , Curvaturas da Coluna Vertebral/fisiopatologia , Fraturas da Coluna Vertebral/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea , Feminino , Fraturas por Compressão/diagnóstico por imagem , Fraturas por Compressão/etiologia , Humanos , Pessoa de Meia-Idade , Osteoporose/complicações , Osteoporose/diagnóstico por imagem , Postura , Estudos Prospectivos , Qualidade de Vida , Análise de Regressão , Autorrelato , Curvaturas da Coluna Vertebral/complicações , Curvaturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/etiologia , Coluna Vertebral/diagnóstico por imagem , Coluna Vertebral/fisiopatologia
10.
Artigo em Inglês | MEDLINE | ID: mdl-29772741

RESUMO

This study examined the changes in spinal kinematics and muscle recruitment of the lumbopelvic region associated with prolonged squatting. Eight subjects with chronic nonspecific low back pain (LBP) and eight asymptomatic subjects (AS) performed squat-to-stand and reverse movements, before and immediately after 15 min deep-squatting. Within-group and between-group differences in lumbopelvic kinematics and electromyographic activity acquired in lumbar erector spinae (ES), gluteus maximus (GM), and vastus lateralis (VL) were analyzed. During squat-to-stand after squatting, the LBP group showed slower then faster lumbar movement in the second and third quartiles, respectively. In the second quartile, the AS group moved with a significantly greater lumbar angle. However, significantly greater bilateral GM activity (+4⁻4.5%) was found in the LBP group only. A more profound decrease in bilateral ES activity (-10%) was also shown in the LBP group, yet this was nonsignificant compared to the AS group (-4%). In the third quartile, only the LBP group moved with a significantly greater lumbar angle, together with a significant increase in bilateral ES (+6⁻8%) and GM muscle (+2⁻3%) activity. The findings of the altered pattern of joint kinematics and recruitment of the key lumbopelvic muscles displayed in the LBP group inform on the possible mechanisms that may contribute to the increased risk of developing lumbar dysfunctions for people who work in prolonged squatting postures.


Assuntos
Dor Crônica/etiologia , Dor Lombar/etiologia , Região Lombossacral/fisiopatologia , Músculo Esquelético/fisiopatologia , Doenças Profissionais/etiologia , Postura/fisiologia , Adulto , Fenômenos Biomecânicos , Estudos de Casos e Controles , Dor Crônica/fisiopatologia , Estudos Transversais , Eletromiografia , Humanos , Dor Lombar/fisiopatologia , Masculino , Doenças Profissionais/fisiopatologia , Projetos Piloto , Adulto Jovem
11.
Ann Transl Med ; 6(22): 442, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30596072

RESUMO

BACKGROUND: While the importance of identifying osteoporotic vertebral endplate fracture (EPF) is being recognized; the pathophysiological understanding of EPF till now remain insufficient. In this population-based cross-sectional radiograph study, we aim to investigate the anatomic location characteristics of osteoporotic EPF. METHODS: This study analyzed the anatomical location of osteoporotic EPFs in elderly Chinese population (age ≥65 years). The T4-L4 radiographs of 1,954 elderly Chinese men (mean: 72.3 years) and 1,953 elderly Chinese women (mean: 72.5 years) were evaluated to identify EPF, and vertebral bodies were graded according to Genant's vertebral deformity criteria. RESULTS: Of the 101,582 endplates analyzed, there were 505 EPFs (males: 27.7%; females: 72.3%). Excluding those with both upper endplate and lower endplate involvements, the ratio of upper EPF to lower EPF was 9.63 for males and 4.3 for females (P<0.05). Thoracolumbar junction, particularly L1 (26.4% for males and 24.1% for females) and followed by T12 (20.7% for males and 19.7% for females), had highest prevalence of EPF. With an endplate divided into 5 segments of equal length in the anteroposterior direction and grade 0.5 & 1, grade 2 vertebral deformities analyzed, fractures occurred mostly at the middle segment (70.1% for upper endplates in males and 78.6% for upper endplates in females), followed by second anterior segment (20.9% for upper endplates in males and 14.4% for upper endplates in females). The most anterior and most posterior segments were not primarily involved in EPF. CONCLUSIONS: Osteoporotic EPFs more likely involve the upper endplate rather than lower endplate, with a trend for this effect to be greater in men than in women. These characteristics may help radiographic differential diagnosis for osteoporotic EPF.

12.
SLAS Technol ; 23(2): 179-187, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29241024

RESUMO

To understand women's and men's physiological ranges of liver T1rho relaxation time measured with a single breathhold black blood sequence, this healthy volunteer study was conducted in 62 women (mean age, 38.9 y; range, 18-75 y) and 34 men (mean age, 44.7 y; range, 24-80 y). Approval from the institutional ethics committee was obtained. Magnetic resonance imaging was performed with a 3.0T scanner with six spin-lock times of 0, 10, 20, 25, 35, and 50 ms and a single breathhold of 12 s per slice acquisition. Six slices were acquired for each examination. The results demonstrated that the female liver T1rho value ranged between 35.07 and 51.97 ms and showed an age-dependent decrease, with younger women having a higher measurement. The male liver T1rho value ranged between 34.94 and 43.39 ms, with no evidential age dependence. Postmenopausal women had similar liver T1rho values as men. For women, there was a trend that the liver T1rho value could be 4% to 5% lower during the menstrual phase than during the nonmenstrual phase. For both women and men, no evidential association was seen between body mass index and liver T1rho.


Assuntos
Fígado/diagnóstico por imagem , Imageamento por Ressonância Magnética , Adulto , Fatores Etários , Idoso , Feminino , Voluntários Saudáveis , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Adulto Jovem
13.
Spine (Phila Pa 1976) ; 43(10): E607-E614, 2018 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-29112101

RESUMO

STUDY DESIGN: A population-based radiographic study with longitudinal follow-up. OBJECTIVE: To develop a quantitative index for lumbar disc space narrowing (DSN) evaluation in elderly subjects; to determine how DSN in the elderly is influenced by osteoporosis and sex. SUMMARY OF BACKGROUND DATA: There is paucity of research on quantitative classification of lumbar DSN based on disc areal morphometry. METHODS: With the database of Osteoporotic Fractures in Men (Hong Kong) and Osteoporotic Fractures in Women (Hong Kong) Studies and those who attended the year-4 follow-up (n = 1519 for men and n = 1546 for women), data of 491 women and 592 men were randomly selected. The anterior, middle, and posterior heights; anteroposterior diameter; and area of intervertebral discs (T4T5 to L4L5) were measured on lateral radiographs. Disc area index for lumbar spine (DAIL, disc area divided by the mean of the sum of square of the adjacent upper and lower vertebrae mid-height anterior-posterior diameter) was developed and compared with semiquantitative DSN expert grading. RESULTS: DAIL correlated with semiquantitative grading, with sensitivity and specificity varying from 87.3% to 96.8% for grade 1 DSN (<30% reduction in disc height), and 92.9% to 100% for grade 3 DSN (>60% reduction in disc height). The thoracolumbar disc area loss among men and women during 4-years' follow-up period varied between 1.32% and 3.56%, and it was greater for women (mean: 2.44%) than for men (mean: 1.90%, P = 0.044). Majority of lumbar DSN progressions during 72 to 76 years old were progression from normal disc space to grade 1 DSN. Osteoporosis was associated with greater disc area decrease, both for thoracic and lumbar discs. CONCLUSION: Lumbar DSN can be quantified using DAIL. In elderly Chinese, intervertebral disc narrowing over a 4-year period was greater in women than men, and associated with the presence of osteoporosis. LEVEL OF EVIDENCE: 3.


Assuntos
Povo Asiático , Progressão da Doença , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/epidemiologia , Vértebras Lombares/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Hong Kong/epidemiologia , Humanos , Disco Intervertebral/diagnóstico por imagem , Estudos Longitudinais , Masculino
14.
FEBS J ; 284(17): 2829-2842, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28650586

RESUMO

Our understanding of how enzymes work is coloured by static structure depictions where the enzyme scaffold is presented as either immobile, or in equilibrium between well-defined static conformations. Proteins, however, exhibit a large degree of motion over a broad range of timescales and magnitudes and this is defined thermodynamically by the enzyme free energy landscape (FEL). The role and importance of enzyme motion is extremely contentious. Much of the challenge is in the experimental detection of so called 'conformational sampling' involved in enzyme turnover. Herein we apply combined pressure and temperature kinetics studies to elucidate the full suite of thermodynamic parameters defining an enzyme FEL as it relates to enzyme turnover. We find that the key thermodynamic parameters governing vibrational modes related to enzyme turnover are the isobaric expansivity term and the change in heat capacity for enzyme catalysis. Variation in the enzyme FEL affects these terms. Our analysis is supported by a range of biophysical and computational approaches that specifically capture information on protein vibrational modes and the FEL (all atom flexibility calculations, red edge excitation shift spectroscopy and viscosity studies) that provide independent evidence for our findings. Our data suggest that restricting the enzyme FEL may be a powerful strategy when attempting to rationally engineer enzymes, particularly to alter thermal activity. Moreover, we demonstrate how rational predictions can be made with a rapid computational approach.


Assuntos
Proteínas de Bactérias/química , Complexo Sacarase-Isomaltase/química , alfa-Glucosidases/química , Algoritmos , Bacillus subtilis/enzimologia , Biocatálise , Domínio Catalítico , Cinética , Modelos Moleculares , Ligação Proteica , Termodinâmica
15.
J Bone Miner Metab ; 35(3): 330-337, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-27225167

RESUMO

Clinical risk factors to predict fracture are useful in guiding management of patients with osteoporosis or falls. Clinical predictors may however be population specific because of differences in lifestyle, environment and ethnicity. Four thousand community-dwelling Chinese males and females with average ages of 72.4 and 72.6 years were followed up for incident fractures, with an average of 6.5 and 8.8 years, respectively. Clinical information was collected, and bone mineral density (BMD) measurements were carried out at baseline. Stepwise Cox regression models were used to identify risk factors of nonvertebral fractures, with BMD as covariate. Areas under the receiver-operating characteristic (ROC) curve (AUC) were compared among different risk models. The incidence rates of nonvertebral fractures were 10.3 and 20.5 per 1000 person years in males and females, respectively. In males, age ≥80, history of a fall in the past year, fracture history, chronic obstructive pulmonary disease, impaired visual depth perception and low physical health-related quality of life were significant fracture risk factors, independent of BMD. In females, the significant factors were fracture history, low visual acuity and slow narrow walking speed. The clinical risk factors had a significant influence on fracture risk irrespective of osteoporosis status, even having a better risk discrimination than BMD alone, especially in males. The best risk prediction model consisted both BMD and clinical risk factors. Clinical risk factors have additive value to hip BMD in predicting nonvertebral fractures in older Chinese people and may predict them better than BMD alone in older Chinese males.


Assuntos
Povo Asiático , Fraturas Ósseas/etiologia , Osteoporose/complicações , Idoso , Área Sob a Curva , Densidade Óssea , Feminino , Fraturas Ósseas/epidemiologia , Hong Kong/epidemiologia , Humanos , Masculino , Análise Multivariada , Osteoporose/epidemiologia , Osteoporose/fisiopatologia , Modelos de Riscos Proporcionais , Qualidade de Vida , Fatores de Risco
16.
J Bone Miner Res ; 32(3): 633-640, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27753150

RESUMO

Measurement of serum testosterone (T) levels is recommended in the evaluation of osteoporosis in older men and estradiol (E2) and sex hormone binding globulin (SHBG) levels are associated with the rate of bone loss and fractures, but the clinical utility of sex steroid and SHBG measurements for the evaluation of osteoporosis in men has not been examined. To evaluate whether measurements of T, E2, and/or SHBG are useful for the prediction of fracture risk or the rate of bone loss in older men, we analyzed longitudinal data from 5487 community-based men participating in the Osteoporotic Fractures in Men (MrOS) study in the United States, Sweden, and Hong Kong. Serum T, E2, and SHBG levels were assessed at baseline; incident fractures were self-reported at 4-month intervals with radiographic verification (US), or ascertained via national health records (Sweden, Hong Kong). Rate of bone loss was assessed by serial measures of hip bone mineral density (BMD). We used receiver operating characteristic (ROC) curves, net reclassification improvement (NRI), and integrated discrimination improvement (IDI) to assess improvement in prediction. Mean age at baseline was 72 to 75 years and the prevalence of low T levels (<300 ng/dL) was 7.6% to 21.3% in the three cohorts. There were 619 incident major osteoporotic and 266 hip fractures during follow-up of approximately 10 years. Based on ROC curves, there were no improvements in fracture risk discrimination for any biochemical measure when added to models, including the Fracture Risk Assessment Tool (FRAX) with BMD. Although minor improvements in NRI were observed for the dichotomous parameters low bioavailable E2 (BioE2) (<11.4 pg/mL) and high SHBG (>59.1 nM), neither sex steroids nor SHBG provided clinically useful improvement in fracture risk discrimination. Similarly, they did not contribute to the prediction of BMD change. In conclusion, there is limited clinical utility of serum E2, T, and SHBG measures for the evaluation of osteoporosis risk in elderly men. © 2016 American Society for Bone and Mineral Research.


Assuntos
Reabsorção Óssea/diagnóstico , Estradiol/sangue , Fraturas Ósseas/diagnóstico , Fraturas Ósseas/epidemiologia , Globulina de Ligação a Hormônio Sexual/metabolismo , Testosterona/sangue , Idoso , Reabsorção Óssea/sangue , Estudos de Coortes , Fraturas Ósseas/sangue , Fraturas do Quadril/sangue , Fraturas do Quadril/diagnóstico , Fraturas do Quadril/epidemiologia , Humanos , Masculino , Curva ROC , Fatores de Risco
17.
Spine (Phila Pa 1976) ; 41(13): 1096-1103, 2016 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-26890951

RESUMO

STUDY DESIGN: Longitudinal follow-up study. OBJECTIVE: This current study aimed to further assess progression, incidence, and risk factors of lumbar spondylolisthesis in these subjects at 4-year follow-up. SUMMARY OF BACKGROUND DATA: A survey for osteoporotic fractures in Hong Kong during 2001 to 2003 represented the first large scale prospective population-based study on bone health in elderly (≥65 years) Chinese men and women. A follow-up study was performed at year-4. METHODS: The lateral lumbar radiographs of 1519 male and 1546 female subjects at year-4 follow-up were analyzed using the Meyerding classification, and compared with the baseline findings. RESULTS: Spondylolisthesis progressed in 13.0%, and de novo spondylolisthesis appeared in 12.4% in men. Spondylolisthesis progressed in 16.5%, and de novo spondylolisthesis appeared in 12.7% in women. In women, higher weight, body mass index, spine and hip bone mineral density (BMD), lower physical activity and lower grip strength were significant factors associated with spondylolisthesis progression, whereas only higher spine BMD was a marginally significant factor associated with spondylolisthesis progression for men. A weak association was noted between spondylolisthesis and lower back pain incidence in women, but not in men. CONCLUSION: Lumbar spondylolisthesis progression in elderly Chinese at 4-year follow-up was characterized by this study. LEVEL OF EVIDENCE: 3.


Assuntos
Povo Asiático , Progressão da Doença , Vértebras Lombares/diagnóstico por imagem , Vigilância da População , Espondilolistese/diagnóstico por imagem , Espondilolistese/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Hong Kong/epidemiologia , Humanos , Masculino , Osteoporose/diagnóstico por imagem , Osteoporose/epidemiologia , Fraturas por Osteoporose/diagnóstico por imagem , Fraturas por Osteoporose/epidemiologia , Estudos Prospectivos , Fatores de Risco
18.
J Back Musculoskelet Rehabil ; 29(3): 503-13, 2016 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-26836833

RESUMO

BACKGROUND: The objective of this study is to evaluate the effects of the Multi-disciplinary Orthopaedics Rehabilitation Empowerment (MORE) Program on reducing chronic disability among injured workers and improving efficiency of work rehabilitation process. METHODS: A cohort of patients with workplace injuries in the lower back were recruited from orthopaedics clinics and assigned to either MORE group (n= 139) or control group (n= 106). Patients in MORE group received an early MRI screening and a coordinated multi-disciplinary management, while patients in the control group received conventional care. Outcome variables are time to return-to-work (RTW) from date of injury, waiting time for MRI screening and time to medical assessment board (MAB). RESULTS: Patients in the MORE Program had significantly shorter duration for RTW (MORE: 6.1 months, CONTROL: 12.8 months, p< 0.01), and more RTW cases (n= 64, 46.0%) compared to CONTROL group (n= 29, 27.4%). The MORE group also had much shorter waiting time for MRI scans (91.85 vs. 309.2 days, p< 0.001) and MAB referral after MRI scans (97.2 vs. 178.9 days, p= 0.001) compared to CONTROL group. CONCLUSIONS: The MORE Program which emphasizes early intervention and early MRI screening, is shown to be effective in shortening sick leave and improving RTW outcomes of injured workers.


Assuntos
Pessoas com Deficiência/reabilitação , Traumatismos Ocupacionais/reabilitação , Procedimentos Ortopédicos/métodos , Licença Médica , Padrão de Cuidado , Local de Trabalho , Adulto , Idoso , Feminino , Hong Kong , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Traumatismos Ocupacionais/diagnóstico por imagem , Retorno ao Trabalho , Resultado do Tratamento , Adulto Jovem
19.
J Rheumatol ; 41(10): 1990-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24986848

RESUMO

OBJECTIVE: To determine changes of bone mineral density (BMD) over a 5-year period in a cohort of female patients with systemic lupus erythematosus (SLE) and to identify factors predictive of BMD loss. METHODS: Our longitudinal study involved 125 female patients with SLE with a mean (SD) age of 46.5 years (10.1) and a median disease duration of 10.4 years. Demographics and clinical data were collected and BMD at the femoral neck, total hip, and lumbar spine (L1-4) was performed by using dual-energy x-ray absorptiometry at baseline and followup. RESULTS: Average percentage changes of BMD over a mean followup of 5 years were -2.41% at the femoral neck, -1.63% at the total hip, and -0.62% at the lumbar spine, with significant changes at both the femoral neck (p < 0.0001) and total hip (p < 0.0005), but not at the lumbar spine (p = 0.128). Disease flare, new organ damage, and use of glucocorticoids during followup were significantly associated with larger decreases in BMD. BMD loss was arrested at the femoral neck and BMD increased at the total hip and lumbar spine in patients receiving antiosteoporosis therapy. In multivariate analyses, use of antiosteoporosis therapy was independently associated with increased BMD at any site and new organ damage was an independent predictor of BMD loss at the femoral neck. CONCLUSION: Significant BMD loss at the hip over a period of 5 years was found in patients with SLE. Disease activity, disease damage, and use of glucocorticoids are the disease-specific variables that contribute to bone loss in SLE.


Assuntos
Densidade Óssea/fisiologia , Colo do Fêmur/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Absorciometria de Fóton , Adulto , Idoso , Progressão da Doença , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Pessoa de Meia-Idade , Valor Preditivo dos Testes
20.
J Bone Miner Res ; 29(9): 2118-29, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24644043

RESUMO

In this cross-sectional study, we investigated volumetric bone mineral density (vBMD), bone microstructure, and biomechanical competence of the distal radius in male patients with rheumatoid arthritis (RA). The study cohort comprised 50 male RA patients of average age of 61.1 years and 50 age-matched healthy males. Areal BMD (aBMD) of the hip, lumbar spine, and distal radius was measured by dual-energy X-ray absorptiometry. High-resolution peripheral quantitative computed tomography (HR-pQCT) of the distal radius provided measures of cortical and trabecular vBMD, microstructure, and biomechanical indices. aBMD of the hip but not the lumbar spine or ultradistal radius was significantly lower in RA patients than controls after adjustment for body weight. Total, cortical, and trabecular vBMD at the distal radius were, on average, -3.9% to -23.2% significantly lower in RA patients, and these differences were not affected by adjustment for body weight, testosterone level, or aBMD at the ultradistal radius. Trabecular microstructure indices were, on average, -8.1% (trabecular number) to 28.7% (trabecular network inhomogeneity) significantly inferior, whereas cortical pore volume and cortical porosity index were, on average, 80.3% and 63.9%, respectively, significantly higher in RA patients. RA patients also had significantly lower whole-bone stiffness, modulus, and failure load, with lower and more unevenly distributed cortical and trabecular stress. Density and microstructure indices significantly correlated with disease activity, severity, and levels of pro-inflammatory cytokines (interleukin [IL] 12p70, tumor necrosis factor, IL-6 and IL-1ß). Ten RA patients had focal periosteal bone apposition most prominent at the ulnovolar aspect of the distal radius. These patients had shorter disease duration and significantly higher cortical porosity. In conclusion, HR-pQCT reveals significant alterations of bone density, microstructure, and strength of the distal radius in male RA patients and provides new insight into the microstructural basis of bone fragility accompanying chronic inflammation.


Assuntos
Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/fisiopatologia , Densidade Óssea , Rádio (Anatomia)/patologia , Rádio (Anatomia)/fisiopatologia , Tomografia Computadorizada por Raios X , Artrite Reumatoide/patologia , Fenômenos Biomecânicos , Estudos de Casos e Controles , Estudos Transversais , Citocinas/metabolismo , Análise de Elementos Finitos , Humanos , Mediadores da Inflamação/metabolismo , Masculino , Pessoa de Meia-Idade , Periósteo/diagnóstico por imagem , Periósteo/patologia , Periósteo/fisiopatologia , Rádio (Anatomia)/diagnóstico por imagem
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