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1.
Hong Kong Med J ; 26(1): 27-34, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-32051330

RESUMO

INTRODUCTION: Studies of Caucasian populations have shown that beta-blockers may exacerbate weight gain, a risk factor for many chronic diseases. Still, beta-blockers are the most prescribed antihypertensives in the Chinese population in Hong Kong. We aimed to explore the association between beta-blocker use, hypertension, and weight status of this population. METHODS: A post-hoc analysis regarding body mass index (BMI) and the use of beta-blockers was performed based on the medication profile of community-dwelling older adults. Participants' BMI, hypertension diagnosis, name, dose, frequency, route of administration of beta-blockers, and other drugs that may alter body weight were recorded. RESULTS: Of 1053 Chinese individuals aged ≥65 years (mean age 76.9±7.2 years, 80% female) from 32 elderly centres in Hong Kong, 18% (185/1053) of them consumed beta-blockers. That group also had a significantly larger proportion of obese individuals (45.9% vs 32.1%, P=0.002). After adjusting for other weight-altering drugs, beta-blockers remained a significant predictor of overweight and obesity (P=0.001). As the hypertensive population had significantly higher BMI than the normotensive population (24.3±3.6 vs 22.9±3.5, P<0.001), a sub-analysis on those with hypertension diagnosis confirmed that only the hypertensive population taking atenolol had a significantly larger population of obese individuals (BMI ≥25) compared with those who took metoprolol (58.9% vs 38.5%, P=0.03) and those who did not take any beta-blockers (58.9% vs 38.4%, P=0.007). CONCLUSIONS: Our findings taken together with other guideline reservations cast doubt on whether beta-blockers, particularly atenolol, should be the major drug prescribed to older adults with hypertension.


Assuntos
Antagonistas Adrenérgicos beta/efeitos adversos , Atenolol/efeitos adversos , Hipertensão/tratamento farmacológico , Obesidade/epidemiologia , Aumento de Peso/efeitos dos fármacos , Antagonistas Adrenérgicos beta/uso terapêutico , Idoso , Idoso de 80 Anos ou mais , Povo Asiático , Atenolol/uso terapêutico , Pressão Sanguínea/efeitos dos fármacos , Índice de Massa Corporal , Feminino , Hong Kong/epidemiologia , Humanos , Hipertensão/complicações , Masculino , Metoprolol/uso terapêutico , Obesidade/etiologia , Fatores de Risco
2.
J Biomech Eng ; 141(1)2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-30167668

RESUMO

Sex differences in the mechanical properties of different musculoskeletal tissues and their impact on tendon function and disease are becoming increasingly recognized. Tendon mechanical properties are influenced by the presence or absence of sex hormones and these effects appear to be tendon- or ligament-specific. The objective of this study was to determine how sex and hormone differences in rats affect supraspinatus tendon and muscle properties. We hypothesized that male supraspinatus tendons would have increased cross-sectional area but no differences in tendon material properties or muscle composition when compared to supraspinatus tendons from female or ovariectomized (OVX) female rats. Uninjured supraspinatus tendons and muscles from male, female, and OVX female rats were collected and mechanical and histological properties were determined. Our analysis demonstrated decreased dynamic modulus and increased hysteresis and cross-sectional area in male tendons. We found that male tendons exhibited decreased dynamic modulus (during low strain frequency sweep and high strain fatigue loading), increased hysteresis, and increased cross-sectional area compared to female and OVX female tendons. Despite robust mechanical differences, tendon cell density and shape, and muscle composition remained unchanged between groups. Interestingly, these differences were unique compared to previously reported sex differences in rat Achilles tendons, which further supports the concept that the effect of sex on tendon varies anatomically. These differences may partially provide a mechanistic explanation for the increased rate of acute supraspinatus tendon ruptures seen in young males.


Assuntos
Fenômenos Mecânicos , Caracteres Sexuais , Tendões/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Hormônios Esteroides Gonadais/metabolismo , Humanos , Masculino , Ombro , Tendões/citologia
3.
Osteoporos Int ; 29(9): 2049-2057, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29855664

RESUMO

The study showed that in African-American men with type 2 diabetes mellitus (T2D), vertebral volumetric bone mineral density (vBMD) predicts all-cause mortality, independent of other risk factors for death. INTRODUCTION: Compared to European Americans, African Americans have lower rates of osteoporosis and higher rates of T2D. The relationships between BMD and fractures with mortality are unknown in this population. The aim of this study was to determine relationships between vertebral fractures and vertebral vBMD and mortality in African Americans with T2D. METHODS: Associations between vertebral fractures and vBMD with all-cause mortality were examined in 675 participants with T2D (391 women and 284 men) in the African American-Diabetes Heart Study (AA-DHS). Lumbar and thoracic vBMD were measured using quantitative computed tomography (QCT). Vertebral fractures were assessed on sagittal CT images. Associations of vertebral fractures and vBMD with all-cause mortality were determined in sex-stratified analyses and in the full sample. Covariates in a minimally adjusted model included age, sex, BMI, smoking, and alcohol use; the full model was adjusted for those variables plus cardiovascular disease, hypertension, coronary artery calcified plaque, hormone replacement therapy (women), African ancestry proportion, and eGFR. RESULTS: After mean 7.6 ± 1.8-year follow-up, 59 (15.1%) of women and 58 (20.4%) of men died. In men, vBMD was inversely associated with mortality in the fully adjusted model: lumbar hazard ratio (HR) per standard deviation (SD) = 0.70 (95% CI 0.52-0.95, p = 0.02) and thoracic HR per SD = 0.71 (95% CI 0.54-0.92, p = 0.01). Only trends toward association between vBMD and mortality were observed in the combined sample of men and women, as significant associations were absent in women. Vertebral fractures were not associated with mortality in either sex. CONCLUSIONS: Lower vBMD was associated with increased all-cause mortality in African-American men with T2D, independent of other risk factors for mortality including subclinical atherosclerosis.


Assuntos
Negro ou Afro-Americano/estatística & dados numéricos , Densidade Óssea/fisiologia , Diabetes Mellitus Tipo 2/etnologia , Osteoporose/etnologia , Fraturas da Coluna Vertebral/etnologia , Idoso , Diabetes Mellitus Tipo 2/mortalidade , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Seguimentos , Humanos , Estimativa de Kaplan-Meier , Vértebras Lombares/fisiopatologia , Masculino , Pessoa de Meia-Idade , North Carolina/epidemiologia , Osteoporose/mortalidade , Osteoporose/fisiopatologia , Fraturas por Osteoporose/etnologia , Fraturas por Osteoporose/mortalidade , Fraturas por Osteoporose/fisiopatologia , Fraturas da Coluna Vertebral/mortalidade , Fraturas da Coluna Vertebral/fisiopatologia , Vértebras Torácicas/fisiopatologia , Tomografia Computadorizada por Raios X/métodos
4.
Osteoporos Int ; 29(9): 2101-2109, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29858634

RESUMO

The American Orthopaedic Association initiated the Own the Bone (OTB) quality improvement program in 2009. Herein we show that the data collected through this program is similar to that collected in other large studies. Thus, the OTB registry functions as an externally valid cohort for studying fragility fracture patients. INTRODUCTION: The American Orthopedic Association initiated the Own the Bone (OTB) quality improvement program in 2009 to improve secondary prevention of fragility fractures. In this study, we present a summary of the data collected by the OTB program and compare it to data from other large fragility fracture registries with an aim to externally validate the OTB registry. METHODS: The OTB registry contained 35,038 unique cases of fragility fracture as of September, 2016. We report the demographics, presenting fracture characteristics, past fracture history, and bone mineral density (BMD) data and compare these to data from large fragility fracture studies across the world. RESULTS: Seventy-three percent of the patients in the OTB registry were female, Caucasian, and post-menopausal. In 54.4% of cases, patients had a hip fracture; spine fractures were the second most common fracture type occurring in 11.1% of patients. Thirty-four percent of the patients had a past history of fragility fracture, and the most common sites were the spine and hip. The average femoral neck T-score was - 2.06. When compared to other studies, the OTB database showed similar findings with regard to patient age, gender, race, BMI, BMD profile, prior fracture history, and family history of fragility fractures. CONCLUSION: OTB is the first and largest multi-center voluntary fragility fracture registry in the USA. The data collected through the OTB program is comparable to that collected in international studies. Thus, the OTB registry functions as an externally valid cohort for further studies assessing the clinical characteristics, interventions, and outcomes achieved in patients who present with a fragility fracture in the USA.


Assuntos
Fraturas por Osteoporose/epidemiologia , Melhoria de Qualidade , Sistema de Registros , Prevenção Secundária/normas , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Conservadores da Densidade Óssea/uso terapêutico , Bases de Dados Factuais , Uso de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoporose/tratamento farmacológico , Fraturas por Osteoporose/fisiopatologia , Fraturas por Osteoporose/prevenção & controle , Distribuição por Sexo , Estados Unidos/epidemiologia
5.
Am J Transplant ; 17(6): 1540-1548, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27862962

RESUMO

Renal allografts from deceased African American donors with two apolipoprotein L1 gene (APOL1) renal-risk variants fail sooner than kidneys from donors with fewer variants. The Kidney Donor Risk Index (KDRI) was developed to evaluate organ offers by predicting allograft longevity and includes African American race as a risk factor. Substituting APOL1 genotype for race may refine the KDRI. For 622 deceased African American kidney donors, we applied a 10-fold cross-validation approach to estimate contribution of APOL1 variants to a revised KDRI. Cross-validation was repeated 10 000 times to generate distribution of effect size associated with APOL1 genotype. Average effect size was used to derive the revised KDRI weighting. Mean current-KDRI score for all donors was 1.4930 versus mean revised-KDRI score 1.2518 for 529 donors with no or one variant and 1.8527 for 93 donors with two variants. Original and revised KDRIs had comparable survival prediction errors after transplantation, but the spread in Kidney Donor Profile Index based on presence or absence of two APOL1 variants was 37 percentage points. Replacing donor race with APOL1 genotype in KDRI better defines risk associated with kidneys transplanted from deceased African American donors, substantially improves KDRI score for 85-90% of kidneys offered, and enhances the link between donor quality and recipient need.


Assuntos
Apolipoproteína L1/genética , Biomarcadores/metabolismo , Variação Genética , Rejeição de Enxerto/mortalidade , Transplante de Rim/mortalidade , Grupos Raciais/genética , Doadores de Tecidos , Adolescente , Adulto , Estudos de Coortes , Feminino , Seguimentos , Genótipo , Rejeição de Enxerto/epidemiologia , Rejeição de Enxerto/genética , Sobrevivência de Enxerto , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Taxa de Sobrevida , Estados Unidos/epidemiologia , Adulto Jovem
6.
Genes Immun ; 16(2): 142-50, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25569266

RESUMO

A classic T-cell phenotype in systemic lupus erythematosus (SLE) is the downregulation and replacement of the CD3ζ chain that alters T-cell receptor signaling. However, genetic associations with SLE in the human CD247 locus that encodes CD3ζ are not well established and require replication in independent cohorts. Our aim was therefore to examine, localize and validate CD247-SLE association in a large multiethnic population. We typed 44 contiguous CD247 single-nucleotide polymorphisms (SNPs) in 8922 SLE patients and 8077 controls from four ethnically distinct populations. The strongest associations were found in the Asian population (11 SNPs in intron 1, 4.99 × 10(-4) < P < 4.15 × 10(-2)), where we further identified a five-marker haplotype (rs12141731-rs2949655-rs16859085-rs12144621-rs858554; G-G-A-G-A; P(hap) = 2.12 × 10(-5)) that exceeded the most associated single SNP rs858554 (minor allele frequency in controls = 13%; P = 4.99 × 10(-4), odds ratio = 1.32) in significance. Imputation and subsequent association analysis showed evidence of association (P < 0.05) at 27 additional SNPs within intron 1. Cross-ethnic meta-analysis, assuming an additive genetic model adjusted for population proportions, showed five SNPs with significant P-values (1.40 × 10(-3) < P< 3.97 × 10(-2)), with one (rs704848) remaining significant after Bonferroni correction (P(meta) = 2.66 × 10(-2)). Our study independently confirms and extends the association of SLE with CD247, which is shared by various autoimmune disorders and supports a common T-cell-mediated mechanism.


Assuntos
Complexo CD3/genética , Lúpus Eritematoso Sistêmico/etnologia , Lúpus Eritematoso Sistêmico/genética , Adulto , Povo Asiático/genética , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Haplótipos , Humanos , Masculino , Polimorfismo de Nucleotídeo Único , Linfócitos T/imunologia , População Branca/genética
7.
Am J Transplant ; 15(6): 1615-22, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25809272

RESUMO

Apolipoprotein L1 gene (APOL1) nephropathy variants in African American deceased kidney donors were associated with shorter renal allograft survival in a prior single-center report. APOL1 G1 and G2 variants were genotyped in newly accrued DNA samples from African American deceased donors of kidneys recovered and/or transplanted in Alabama and North Carolina. APOL1 genotypes and allograft outcomes in subsequent transplants from 55 U.S. centers were linked, adjusting for age, sex and race/ethnicity of recipients, HLA match, cold ischemia time, panel reactive antibody levels, and donor type. For 221 transplantations from kidneys recovered in Alabama, there was a statistical trend toward shorter allograft survival in recipients of two-APOL1-nephropathy-variant kidneys (hazard ratio [HR] 2.71; p = 0.06). For all 675 kidneys transplanted from donors at both centers, APOL1 genotype (HR 2.26; p = 0.001) and African American recipient race/ethnicity (HR 1.60; p = 0.03) were associated with allograft failure. Kidneys from African American deceased donors with two APOL1 nephropathy variants reproducibly associate with higher risk for allograft failure after transplantation. These findings warrant consideration of rapidly genotyping deceased African American kidney donors for APOL1 risk variants at organ recovery and incorporation of results into allocation and informed-consent processes.


Assuntos
Apolipoproteínas/genética , Negro ou Afro-Americano/genética , Variação Genética/genética , Rejeição de Enxerto/genética , Nefropatias/cirurgia , Transplante de Rim , Lipoproteínas HDL/genética , Doadores de Tecidos , Adolescente , Adulto , Alabama , Aloenxertos , Apolipoproteína L1 , Feminino , Genótipo , Rejeição de Enxerto/etnologia , Rejeição de Enxerto/mortalidade , Humanos , Nefropatias/mortalidade , Transplante de Rim/mortalidade , Masculino , Pessoa de Meia-Idade , North Carolina , Fatores de Risco , Taxa de Sobrevida , Resultado do Tratamento , Adulto Jovem
8.
Arch Orthop Trauma Surg ; 134(9): 1211-7, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25077784

RESUMO

INTRODUCTION: The optimal timing of surgery for multiply injured patients with operative spinal injuries remains unknown. The purported benefits of early intervention must be weighed against the morbidity of surgery in the early post-injury period. The performance of spine surgery in the Afghanistan theater permits analysis of the morbidity of early surgery on military casualties. The objective is to compare surgical morbidity of early spinal surgery in multiply injured patients versus stable patients. MATERIALS AND METHODS: Patients were retrospectively categorized as stable or borderline unstable depending on the presence of at least one of the following: ISS >40, ISS >20 and chest injury, exploratory laparotomy or thoracotomy, lactate >2.5 mEq/L, platelet <110,000/mm(3), or >10 U PRBCs transfused pre-operatively. Surgical morbidity, complications, and neurologic improvement between the two groups were compared retrospectively. RESULTS: 30 casualties underwent 31 spine surgeries during a 12-month period. 16 of 30 patients met criteria indicating a borderline unstable patient. Although there were no significant differences in the procedures performed for stable and borderline unstable patients as measured by the Surgical Invasiveness Index (7.5 vs. 6.9, p = 0.8), borderline unstable patients had significantly higher operative time (4.3 vs. 3.0 h, p = 0.01), blood loss (1,372 vs. 366 mL, p = 0.001), PRBCs transfused intra-op (3.88 vs. 0.14 U, p < 0.001), and total PRBCs transfused in theater (10.18 vs. 0.31 U, p < 0.001). CONCLUSIONS: The results indicate that published criteria defining a borderline unstable patient may have a role in predicting increased morbidity of early spine surgery. The perceived benefits of early intervention should be weighed against the greater risks of performing extensive spinal surgeries on multiply injured patients in the early post-injury period, especially in the setting of combat trauma.


Assuntos
Militares , Traumatismo Múltiplo/cirurgia , Traumatismos da Medula Espinal/cirurgia , Traumatismos da Coluna Vertebral/cirurgia , Adulto , Campanha Afegã de 2001- , Perda Sanguínea Cirúrgica/estatística & dados numéricos , Transfusão de Eritrócitos/estatística & dados numéricos , Feminino , Humanos , Escala de Gravidade do Ferimento , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Melhoria de Qualidade , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Estados Unidos
9.
Int J Cardiol Heart Vasc ; 53: 101443, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39040629

RESUMO

Background: Atrial fibrillation (AF) is associated with stroke. Major changes to AF management recommendations in 2016-2018 advised that: 1. Stroke risk be estimated using the CHA2DS2-VA score; 2. Antiplatelet agents (APAs) do not effectively mitigate stroke risk; 3. Anticoagulation is prioritised above bleeding risk among high-risk patients; and 4. Non-vitamin K oral anticoagulants (NOACs) are used as first-line anticoagulants. Aim: To examine trends in stroke risk management among high-risk patients with non-valvular AF in Australia between 2011-2019. Method: De-identified data of patients were obtained from 164 separate general practices. Data included information on patient demographics, diagnoses, health risk factors and recent prescriptions. Patients with a diagnosis of non-valvular AF were identified and stroke risk was calculated by CHA2DS2-VA score. High risk patients (i.e. CHA2DS2-VA ≥ 2) were categorised as being managed by oral anticoagulants (OACs, i.e., warfarin or NOACs), APAs only, or neither (i.e., no OACs or APAs) and time trends in prescribing were examined. Multivariate analyses examined the characteristics of patients receiving the guideline recommended OAC management. Results: Data were available for 337,964 patients; 8696 (2.6 %) had AF. Most patients with AF (85.8 %, n = 7116) had high stroke risk. The proportion of high-risk patients managed on OACs increased from 56.7 % in 2011 to 73.7 % in 2019, while the proportion prescribed APAs declined from 31.1 % to 14.0 %. Those receiving neither treatment remained steady (around 12 %). Overall, 26.3 % of patients were inadequately anticoagulated at the end of the study period. There were no age or gender differences in receiving the guideline-recommended therapy, and patients with comorbidities associated with increased stroke risk were more likely to receive OAC therapy. Conclusions: Stroke risk management among patients with AF has improved between 2011-2019, however there is still scope for further gains as many high-risk patients remain inadequately anticoagulated. Better stroke risk assessment by clinicians coupled with addressing practitioner concerns about bleeding risk may improve management of high-risk patients.

10.
Minerva Urol Nefrol ; 65(1): 37-50, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23538309

RESUMO

The relationship between hypertension and chronic kidney disease (CKD) has long been the subject of controversy. The pathogenetic mechanisms of nephropathy in non-diabetic individuals with hypertension, as well as optimal hypertension treatment targets in populations with nephropathy remain important clinical concerns. This manuscript reviews breakthroughs in molecular genetics that have clarified the complex relationship between hypertension and kidney disease, answering the question of which factor comes first. An overview of the potential roles that hyperuricemia plays in the pathogenesis of hypertension and CKD and current blood pressure treatment guidelines in populations with CKD are discussed. The ongoing National Institutes of Health-sponsored Systolic Blood Pressure Intervention Trial (SPRINT) is underway to help answer these important questions. Enrollment of 9250 hypertensive SPRINT participants will be completed in 2013; important results on ideal blood pressure control targets for reducing nephropathy progression, cardiovascular disease end-points, and preserving cognitive function are expected. As such, many of the controversial aspects of hypertension management will likely be clarified in the near future.


Assuntos
Hipertensão/complicações , Nefropatias/complicações , Alopurinol/uso terapêutico , Animais , Anti-Hipertensivos/uso terapêutico , Apolipoproteína L1 , Apolipoproteínas/genética , Apolipoproteínas/fisiologia , População Negra/genética , Causalidade , Doença Crônica , Angiopatias Diabéticas/complicações , Angiopatias Diabéticas/fisiopatologia , Nefropatias Diabéticas/fisiopatologia , Gerenciamento Clínico , Modelos Animais de Doenças , Predisposição Genética para Doença , Glomerulosclerose Segmentar e Focal/etnologia , Glomerulosclerose Segmentar e Focal/genética , Objetivos , Humanos , Hipertensão/tratamento farmacológico , Hipertensão/etnologia , Hipertensão/fisiopatologia , Hipertensão Renal/etiologia , Hipertensão Renal/fisiopatologia , Hiperuricemia/complicações , Hiperuricemia/tratamento farmacológico , Hiperuricemia/epidemiologia , Hiperuricemia/fisiopatologia , Nefropatias/etnologia , Nefropatias/fisiopatologia , Lipoproteínas HDL/genética , Lipoproteínas HDL/fisiologia , Estudos Multicêntricos como Assunto , Polimorfismo Genético , Ensaios Clínicos Controlados Aleatórios como Assunto , Ratos
11.
J Dent Res ; 102(5): 497-504, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36883653

RESUMO

Oral lichen planus (OLP) and recurrent aphthous stomatitis (RAS) are common chronic inflammatory conditions, manifesting as painful oral lesions that negatively affect patients' quality of life. Current treatment approaches are mainly palliative and often ineffective due to inadequate contact time of the therapeutic agent with the lesions. Here, we developed the Dental Tough Adhesive (DenTAl), a bioinspired adhesive patch with robust mechanical properties, capable of strong adhesion against diverse wet and dynamically moving intraoral tissues, and extended drug delivery of clobetasol-17-propionate, a first-line drug for treating OLP and RAS. DenTAl was found to have superior physical and adhesive properties compared to existing oral technologies, with ~2 to 100× adhesion to porcine keratinized gingiva and ~3 to 15× stretchability. Clobetasol-17-propionate incorporated into the DenTAl was released in a tunable sustained manner for at least 3 wk and demonstrated immunomodulatory capabilities in vitro, evidenced by reductions in several cytokines, including TNF-α, IL-6, IL-10, MCP-5, MIP-2, and TIMP-1. Our findings suggest that DenTAl may be a promising device for intraoral delivery of small-molecule drugs applicable to the management of painful oral lesions associated with chronic inflammatory conditions.


Assuntos
Clobetasol , Líquen Plano Bucal , Animais , Suínos , Clobetasol/uso terapêutico , Hidrogéis , Qualidade de Vida , Propionatos/uso terapêutico , Cimentos Dentários/uso terapêutico , Doença Crônica
12.
J Mech Behav Biomed Mater ; 140: 105730, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36801782

RESUMO

Medical imaging modalities that calculate tissue morphology alone cannot provide direct information regarding the mechanical behaviour of load-bearing musculoskeletal organs. Accurate in vivo measurement of spine kinematics and intervertebral disc (IVD) strains can provide important information regarding the mechanical behaviour of the spine, help to investigate the effects of injuries on the mechanics of the spine, and assess the effectiveness of treatments. Additionally, strains can serve as a functional biomechanical marker for detecting normal and pathologic tissues. We hypothesised that combining digital volume correlation (DVC) with 3T clinical MRI can provide direct information regarding the mechanics of the spine. Here, we have developed a novel non-invasive tool for in vivo displacement and strain measurement within the human lumbar spine and we used this tool to calculate lumbar kinematics and IVD strains in six healthy subjects during lumbar extension. The proposed tool enabled spine kinematics and IVD strains to be measured with errors that did not exceed 0.17 mm and 0.5%, respectively. The findings of the kinematics study identified that during extension the lumbar spine of healthy subjects experiences total 3D translations ranging from 1 mm to 4.5 mm for different vertebral levels. The findings of strain analysis identified that the average of the maximum tensile, compressive, and shear strains for different lumbar levels during extension ranged from 3.5% to 7.2%. This tool can provide base-line data that can be used to describe the mechanical environment of healthy lumbar spine, which can help clinicians manage preventative treatments, define patient-specific treatments, and to monitor the effectiveness of surgical and non-surgical interventions.


Assuntos
Degeneração do Disco Intervertebral , Disco Intervertebral , Humanos , Fenômenos Biomecânicos , Disco Intervertebral/patologia , Vértebras Lombares/anatomia & histologia , Imageamento por Ressonância Magnética , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/patologia
13.
Sci Robot ; 8(76): eadd9369, 2023 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-36947599

RESUMO

Robot-actuated mechanical loading (ML)-based therapies ("mechanotherapies") can promote regeneration after severe skeletal muscle injury, but the effectiveness of such approaches during aging is unknown and may be influenced by age-associated decline in the healing capacity of skeletal muscle. To address this knowledge gap, this work used a noninvasive, load-controlled robotic device to impose highly defined tissue stresses to evaluate the age dependence of ML on muscle repair after injury. The response of injured muscle to robot-actuated cyclic compressive loading was found to be age sensitive, revealing not only a lack of reparative benefit of ML on injured aged muscles but also exacerbation of tissue inflammation. ML alone also disrupted the normal regenerative processes of aged muscle stem cells. However, these negative effects could be reversed by introducing anti-inflammatory therapy alongside ML application, leading to enhanced skeletal muscle regeneration even in aged mice.


Assuntos
Regeneração , Robótica , Animais , Camundongos , Regeneração/fisiologia , Músculo Esquelético/fisiologia , Anti-Inflamatórios
14.
Genes Immun ; 13(3): 232-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22189356

RESUMO

Systemic lupus erythematosus (SLE) is a complex autoimmune disease characterized by autoantibody production and organ damage. Lupus nephritis (LN) is one of the most severe manifestations of SLE. Multiple studies reported associations between renal diseases and variants in the non-muscle myosin heavy chain 9 (MYH9) and the neighboring apolipoprotein L 1 (APOL1) genes. We evaluated 167 variants spanning MYH9 for association with LN in a multiethnic sample. The two previously identified risk variants in APOL1 were also tested for association with LN in European-Americans (EAs) (N = 579) and African-Americans (AAs) (N = 407). Multiple peaks of association exceeding a Bonferroni corrected P-value of P < 2.03 × 10(-3) were observed between LN and MYH9 in EAs (N = 4620), with the most pronounced association at rs2157257 (P = 4.7 × 10(-4), odds ratio (OR) = 1.205). A modest effect with MYH9 was also detected in Gullah (rs8136069, P = 0.0019, OR = 2.304). No association between LN and MYH9 was found in AAs, Asians, Amerindians or Hispanics. This study provides the first investigation of MYH9 in LN in non-Africans and of APOL1 in LN in any population, and presents novel insight into the potential role of MYH9 in LN in EAs.


Assuntos
Apolipoproteínas/genética , Negro ou Afro-Americano/genética , Lipoproteínas HDL/genética , Nefrite Lúpica/etnologia , Nefrite Lúpica/genética , Proteínas Motores Moleculares/genética , Cadeias Pesadas de Miosina/genética , Apolipoproteína L1 , Predisposição Genética para Doença , Humanos , Desequilíbrio de Ligação , Polimorfismo de Nucleotídeo Único , População Branca/genética
15.
Genes Immun ; 13(5): 380-7, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22476155

RESUMO

Systemic lupus erythematosus (SLE) is an autoimmune disease with diverse clinical manifestations characterized by the development of pathogenic autoantibodies manifesting in inflammation of target organs such as the kidneys, skin and joints. Genome-wide association studies have identified genetic variants in the UBE2L3 region that are associated with SLE in subjects of European and Asian ancestry. UBE2L3 encodes an ubiquitin-conjugating enzyme, UBCH7, involved in cell proliferation and immune function. In this study, we sought to further characterize the genetic association in the region of UBE2L3 and use molecular methods to determine the functional effect of the risk haplotype. We identified significant associations between variants in the region of UBE2L3 and SLE in individuals of European and Asian ancestry that exceeded a Bonferroni-corrected threshold (P<1 × 10(-4)). A single risk haplotype was observed in all associated populations. Individuals harboring the risk haplotype display a significant increase in both UBE2L3 mRNA expression (P=0.0004) and UBCH7 protein expression (P=0.0068). The results suggest that variants carried on the SLE-associated UBE2L3 risk haplotype influence autoimmunity by modulating UBCH7 expression.


Assuntos
Predisposição Genética para Doença , Haplótipos , Lúpus Eritematoso Sistêmico/genética , Enzimas de Conjugação de Ubiquitina/genética , Negro ou Afro-Americano/genética , Alelos , Povo Asiático/genética , Feminino , Hispânico ou Latino/genética , Humanos , Desequilíbrio de Ligação , Lúpus Eritematoso Sistêmico/etnologia , Masculino , Polimorfismo de Nucleotídeo Único , Enzimas de Conjugação de Ubiquitina/metabolismo , População Branca/genética
16.
Int J Obes (Lond) ; 36(3): 465-73, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21750520

RESUMO

OBJECTIVE: Recent genome-wide association studies (GWAS) have identified multiple novel loci associated with adiposity in European-derived study populations. Limited study of these loci has been reported in African Americans. Here we examined the effects of these previously identified adiposity loci in African Americans. METHODS: A total of 46 representative single-nucleotide polymorphisms (SNPs) in 19 loci that were previously reported in GWAS in Europeans (including FTO and MC4R) were genotyped in 4992 subjects from six African-American cohorts. These SNPs were tested for association with body mass index (BMI) after adjustment for age, gender, disease status and population structure in each cohort. Meta-analysis was conducted to combine the results. RESULTS: Meta-analysis of 4992 subjects revealed seven SNPs near four loci, including NEGR1, TMEM18, SH2B1 /ATP2A1 and MC4R, showing significant association at 0.005

Assuntos
Negro ou Afro-Americano/genética , Peso Corporal/genética , Diabetes Mellitus Tipo 2/genética , Obesidade/genética , População Branca/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Adiposidade/genética , Dioxigenase FTO Dependente de alfa-Cetoglutarato , Moléculas de Adesão Celular Neuronais/genética , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Proteínas Ligadas por GPI/genética , Predisposição Genética para Doença , Variação Genética , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Obesidade/epidemiologia , Polimorfismo de Nucleotídeo Único , Proteínas/genética , Receptor Tipo 4 de Melanocortina/genética , Fatores de Transcrição
17.
Diabet Med ; 29(6): 767-70, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22211818

RESUMO

AIMS: Although current American Heart Association guidelines address C-reactive protein concentration and cardiovascular disease risk, it remains unclear whether this paradigm is consistent across populations with differing disease burdens. Individuals with Type 2 diabetes mellitus represent one group at increased risk of cardiovascular disease and subsequent mortality. This study aimed to examine the relationship between C-reactive protein concentrations and risk for all-cause mortality in European Americans with Type 2 diabetes from the Diabetes Heart Study. METHODS: A total of 846 European Americans with Type 2 diabetes and baseline measures of C-reactive protein were evaluated. Vital status was determined after a follow-up period of 7.3 ± 2.1 years (mean ± SD). C-reactive protein concentrations were compared between living and deceased subgroups along with other known risk factors for cardiovascular disease, including blood lipids. Logistic regression was performed to determine risk for mortality associated with increasing C-reactive protein concentrations. RESULTS: At follow-up 160 individuals (18.7%) were deceased. No significant differences in baseline serum glucose or lipid measures were observed between living and deceased subgroups. Baseline C-reactive protein concentrations were significantly higher in the deceased subgroup (9.37 ± 15.94) compared with the living subgroup (5.36 ± 7.91 mg/l; P < 0.0001). Participants with C-reactive protein concentrations of 3-10 mg/l were approximately two times more likely to be deceased at follow-up (OR 2.06; 95% CI 1.17-3.62); those with C-reactive protein >10 mg/l were more than five times more likely to be deceased (OR 5.24; CI 2.80-9.38). CONCLUSIONS: This study documents the utility of C-reactive protein in predicting risk for all-cause mortality in European Americans with Type 2 diabetes and supports its use as a screening tool in risk prediction models.


Assuntos
Proteína C-Reativa/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/mortalidade , Angiopatias Diabéticas/sangue , Angiopatias Diabéticas/mortalidade , População Branca/estatística & dados numéricos , Idoso , Biomarcadores/metabolismo , Estudos de Coortes , Feminino , Seguimentos , Humanos , Inflamação/sangue , Inflamação/mortalidade , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Medição de Risco , Fatores de Risco , Análise de Sobrevida , Estados Unidos/epidemiologia
18.
Genes Immun ; 12(5): 378-89, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21307878

RESUMO

γδ T cells function in innate and adaptive immunity and are primed for secondary responses by procyanidin components of unripe apple peel (APP). In this study, we investigate the effects of APP and purified procyanidins on γδ T-cell gene expression. A microarray analysis was performed on bovine γδ T cells treated with APP; increases in transcripts encoding granulocyte-monocyte colony stimulating factor (GM-CSF), IL-8 and IL-17, but not markers of TCR stimulation such as IFNγ, were observed. Key responses were confirmed in human, mouse and bovine cells by reverse transcription-PCR and/or ELISA, indicating a conserved response to procyanidins. In vivo relevance of the cytokine response was shown in mice following intraperitoneal injection of APP, which induced production of CXCL1/KC and resulted in neutrophil influx to the blood and peritoneum. In the human T-cell line, MOLT-14, GM-CSF and IL-8 transcripts were increased and stabilized in cells treated with crude APP or purified procyanidins. The ERK1/2 MAPK pathway was activated in APP-treated cells, and necessary for transcript stabilization. Our data describe a unique γδ T-cell inflammatory response during procyanidin treatment and suggest that transcript stability mechanisms could account, at least in part, for the priming phenotype.


Assuntos
Citocinas/genética , Proantocianidinas/farmacologia , Estabilidade de RNA/genética , RNA Mensageiro/metabolismo , Subpopulações de Linfócitos T/imunologia , Animais , Bovinos , Linhagem Celular , Citocinas/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Humanos , Fatores Imunológicos/farmacologia , Camundongos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neutrófilos/imunologia , Neutrófilos/metabolismo , Peritônio/imunologia , Peritônio/metabolismo , Estabilidade de RNA/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Subpopulações de Linfócitos T/efeitos dos fármacos , Subpopulações de Linfócitos T/metabolismo , Transcrição Gênica/efeitos dos fármacos
19.
Genes Immun ; 12(4): 270-9, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21270825

RESUMO

Systemic lupus erythematosus (SLE) is a prototypic autoimmune disorder with a complex pathogenesis in which genetic, hormonal and environmental factors have a role. Rare mutations in the TREX1 gene, the major mammalian 3'-5' exonuclease, have been reported in sporadic SLE cases. Some of these mutations have also been identified in a rare pediatric neurological condition featuring an inflammatory encephalopathy known as Aicardi-Goutières syndrome (AGS). We sought to investigate the frequency of these mutations in a large multi-ancestral cohort of SLE cases and controls. A total of 40 single-nucleotide polymorphisms (SNPs), including both common and rare variants, across the TREX1 gene, were evaluated in ∼8370 patients with SLE and ∼7490 control subjects. Stringent quality control procedures were applied, and principal components and admixture proportions were calculated to identify outliers for removal from analysis. Population-based case-control association analyses were performed. P-values, false-discovery rate q values, and odds ratios (OR) with 95% confidence intervals (CI) were calculated. The estimated frequency of TREX1 mutations in our lupus cohort was 0.5%. Five heterozygous mutations were detected at the Y305C polymorphism in European lupus cases but none were observed in European controls. Five African cases incurred heterozygous mutations at the E266G polymorphism and, again, none were observed in the African controls. A rare homozygous R114H mutation was identified in one Asian SLE patient, whereas all genotypes at this mutation in previous reports for SLE were heterozygous. Analysis of common TREX1 SNPs (minor allele frequency (MAF)>10%) revealed a relatively common risk haplotype in European SLE patients with neurological manifestations, especially seizures, with a frequency of 58% in lupus cases compared with 45% in normal controls (P=0.0008, OR=1.73, 95% CI=1.25-2.39). Finally, the presence or absence of specific autoantibodies in certain populations produced significant genetic associations. For example, a strong association with anti-nRNP was observed in the European cohort at a coding synonymous variant rs56203834 (P=2.99E-13, OR=5.2, 95% CI=3.18-8.56). Our data confirm and expand previous reports and provide additional support for the involvement of TREX1 in lupus pathogenesis.


Assuntos
Exodesoxirribonucleases/genética , Lúpus Eritematoso Sistêmico/genética , Fosfoproteínas/genética , Estudos de Coortes , Feminino , Haplótipos , Humanos , Lúpus Eritematoso Sistêmico/epidemiologia , Masculino , Mutação , Fenótipo , Polimorfismo de Nucleotídeo Único
20.
Diabetologia ; 54(3): 544-53, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21127830

RESUMO

AIMS/HYPOTHESIS: This meta-analysis assessed the pooled effect of each genetic variant reproducibly associated with diabetic nephropathy. METHODS: PubMed, EMBASE and Web of Science were searched for articles assessing the association between genes and diabetic nephropathy. All genetic variants statistically associated with diabetic nephropathy in an initial study, then independently reproduced in at least one additional study, were selected. Subsequently, all studies assessing these variants were included. The association between these variants and diabetic nephropathy (defined as macroalbuminuria/proteinuria or end-stage renal disease [ESRD]) was calculated at the allele level and the main measure of effect was a pooled odds ratio. Pre-specified subgroup analyses were performed, stratifying for type 1/type 2 diabetes mellitus, proteinuria/ESRD and ethnic group. RESULTS: The literature search yielded 3,455 citations, of which 671 were genetic association studies investigating diabetic nephropathy. We identified 34 replicated genetic variants. Of these, 21 remained significantly associated with diabetic nephropathy in a random-effects meta-analysis. These variants were in or near the following genes: ACE, AKR1B1 (two variants), APOC1, APOE, EPO, NOS3 (two variants), HSPG2, VEGFA, FRMD3 (two variants), CARS (two variants), UNC13B, CPVL and CHN2, and GREM1, plus four variants not near genes. The odds ratios of associated genetic variants ranged from 0.48 to 1.70. Additional variants were detected in subgroup analyses: ELMO1 (Asians), CCR5 (Asians) and CNDP1 (type 2 diabetes). CONCLUSIONS/INTERPRETATION: This meta-analysis found 24 genetic variants associated with diabetic nephropathy. The relative contribution and relevance of the identified genes in the pathogenesis of diabetic nephropathy should be the focus of future studies.


Assuntos
Nefropatias Diabéticas/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Apolipoproteína C-I/genética , Apolipoproteínas E/genética , Carboxipeptidases/genética , Dipeptidases/genética , Eritropoetina/genética , Variação Genética/genética , Proteoglicanas de Heparan Sulfato/genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas do Tecido Nervoso/genética , Óxido Nítrico Sintase Tipo III/genética , Peptidil Dipeptidase A/genética , Polimorfismo Genético/genética , Receptores CCR5/genética
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