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1.
bioRxiv ; 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38659792

RESUMO

Contingency (or 'luck') in early life plays an important role in shaping individuals' development. When individuals live within larger societies, social experiences may cause the importance of early contingencies to be magnified or dampened. Here we test the hypothesis that competition magnifies the importance of early contingency in a sex-specific manner by comparing the developmental trajectories of genetically identical, free-living mice who either experienced high levels of territorial competition (males) or did not (females). We show that male territoriality results in a competitive feedback loop that magnifies the importance of early contingency and pushes individuals onto divergent, self-reinforcing life trajectories, while the same process appears absent in females. Our results indicate that the strength of sexual selection may be self-limiting, as within-sex competition increases the importance of early life contingency, thereby reducing the ability of selection to lead to evolution. They also demonstrate the potential for contingency to lead to dramatic differences in life outcomes, even in the absence of any underlying differences in ability ('merit').

2.
Arthritis Care Res (Hoboken) ; 76(4): 526-530, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38221659

RESUMO

OBJECTIVE: Although the population of patients with systemic lupus erythematosus (SLE) is racially and ethnically diverse, many study populations are homogeneous. Further, data are often lacking on critical factors, such as antiphospholipid antibodies (aPLs). We investigated live birth rates in patients with SLE at Kaiser Permanente Northern California, including race and ethnicity and aPL data. METHODS: Electronic health records of pregnancies with outcomes observed from 2011 to 2020 were identified among patients with SLE. Prevalent SLE was defined as two or more International Classification of Diseases-coded visits seven or more days apart before the last menstrual period. We summarized patient characteristics, medication orders, health care use, and medication use. Pregnancy outcomes (live birth, stillbirth, spontaneous abortion, ectopic pregnancy, and molar pregnancy) were presented overall and stratified by race and ethnicity, aPL status, and nephritis history. RESULTS: We identified 657 pregnancies among 453 patients with SLE. The cohort was diverse, reflecting the Northern California population (27% Asian, 26% Hispanic, 26% Non-Hispanic White, 13% Non-Hispanic Black, 5% multiracial, and approximately 2% Pacific Islander and Native American). Approximately 74% of observed pregnancies ended in live birth, 23% resulted in spontaneous abortion, 2% were ectopic or molar pregnancies, and <1% were stillbirths. There was limited variability in live births by race and ethnic group (72%-79%), aPL status (69.5%-77%), and nephritis history (71%-75%). CONCLUSION: Our findings are consistent with previous studies; however, some methodologic differences may yield a range of live birth rates. We found that approximately 74% of pregnancies in patients with SLE ended in live birth, with modest variability in spontaneous abortion by race and ethnicity, nephritis history, and aPL status.


Assuntos
Aborto Espontâneo , Lúpus Eritematoso Sistêmico , Nefrite Lúpica , Complicações na Gravidez , Gravidez , Feminino , Humanos , Resultado da Gravidez/epidemiologia , Aborto Espontâneo/epidemiologia , Nefrite Lúpica/diagnóstico , Nefrite Lúpica/epidemiologia , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/epidemiologia , Anticorpos Antifosfolipídeos , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/epidemiologia
3.
ACR Open Rheumatol ; 4(12): 1021-1026, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36252776

RESUMO

OBJECTIVE: Most studies consider either medications ordered or filled, but not both. Medication underuse based on filling data cannot necessarily be ascribed to patient nonadherence. Using both data sources, we quantified primary medication adherence in a cohort of prevalent systemic lupus erythematosus (SLE) pregnancies. METHODS: We identified 419 pregnancies in Kaiser Permanente Northern California in patients with prevalent SLE from 2011 to 2020. We calculated the number of physician-initiated orders or pharmacy-initiated reorders during pregnancy and a comparable 9-month window the year before (prepregnancy) and the proportion of orders ever filled and filled within 30 days for hydroxychloroquine (HCQ), azathioprine, and corticosteroids. For pregnancies without an order or reorder, we identified the proportion with previous prescription fills overlapping into the respective study period. RESULTS: New orders for lupus medications were usually filled. HCQ was prescribed most often (45.8% pregnancies) and usually filled (89.7% in prepregnancy, 93.2% during pregnancy). The majority filled within 30 days (80.5% prepregnancy, 83.3% pregnancy). Some pregnancies without new HCQ orders had continuous refills from prior orders; 53% of 2011-2015 pregnancies either had a new order or fill coverage from a previous period, compared to 63.2% of pregnancies delivering in 2016-2019. Corticosteroid fill frequencies were 90.6% in prepregnancy and 83.6% during pregnancy. Fewer patients used azathioprine; however, most new orders were filled (94.3% prepregnancy, 91.7% pregnancy). For azathioprine and corticosteroids, fill rates were modestly higher in prepregnancy compared to pregnancy. CONCLUSION: We observed that patients have high adherence to filling new orders for lupus medications, such as HCQ and azathioprine, in pregnancy.

4.
Polym J ; 54(6): 821-825, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35311245

RESUMO

Liquid-crystalline (LC) water-treatment membranes obtained by in situ photopolymerization of ionic mesogenic monomers have been shown to efficiently remove viruses. In our previous works, bicontinuous cubic (Cubbi) and smectic (Sm) LC membranes prepared from ionic taper- and rod-shaped polymerizable mesogens, respectively, were used for this purpose. Here, we report the results of virus removal by columnar (Col) LC water-treatment membranes having ionic nanochannels obtained from ionic taper-shaped mesogens. These effects are compared with those obtained for Cubbi membranes. The effects of these Col and Cubbi LC ionic membranes on the removal of several viruses from their cocktail solution are also examined.

5.
Clin Rheumatol ; 40(3): 1077-1084, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32803573

RESUMO

OBJECTIVE: Musculoskeletal ultrasound quantifies the total synovial inflammatory burden in rheumatoid arthritis (RA) but is time consuming when scanning numerous joints. This study evaluated a novel patient-centered method for constructing a longitudinal ultrasound score in RA patients. METHODS: Fifty-four RA patients starting intravenous tocilizumab were evaluated with power Doppler ultrasound (PDUS) of 34 joints and DAS28-ESR was assessed at baseline and weeks 4, 12, 16, and 24. The sentinel joint score (SJS) was derived from the reduced subset of joints with PDUS ≥ 1 at baseline. Total PDUS (tPDUS) score and US7 were also calculated. Changes in tPDUS and SJS were correlated. Effect sizes were calculated for tPDUS, SJS, and US7. The proportion of "flipped" joints without baseline PDUS signal that later developed PDUS signal was estimated. RESULTS: At baseline, 1236/1829 joints scanned (67.5%) did not have PDUS signal. The proportion of "flipped" joints at 24 weeks was 5.6% for ≥ 1, 2.9% for ≥ 2, and 1.0% for = 3 PD. tPDUS and SJS scores were highly correlated (r = 0.91 to 0.97). Overall the effect sizes for tPDUS, SJS, and US7 increased over 24 weeks, where SJS was the highest (SJS 1.00 4-week, 1.07 12-week, 1.26 24-week) and tPDUS and US7 were comparable (tPDUS 0.32 4-week, 0.52 12-week, 0.84 24-week; US7 0.23 4-week, 0.52 12-week, 0.74 24-week). CONCLUSION: In RA patients starting a biologic, scanning only joints with baseline PDUS signal can substantially reduce the number of joints requiring follow-up scanning by 67.5% and improves feasibility. "Flipped" joints are infrequently seen after starting therapy. TRIAL REGISTRATION: ClinicalTrials.gov NCT01717859 Key messages • Only a small percent of joints develop power Doppler signal after baseline scanning. • Changes in the SJS correlate well with changes in clinical activity measured by DAS28-ESR over time. • The SJS effect size is higher than total PDUS and US7 scores, and may improve examination feasibility.


Assuntos
Antirreumáticos , Artrite Reumatoide , Sinovite , Antirreumáticos/uso terapêutico , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/tratamento farmacológico , Humanos , Índice de Gravidade de Doença , Sinovite/tratamento farmacológico , Ultrassonografia , Ultrassonografia Doppler
6.
Small ; 16(23): e2001721, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32363808

RESUMO

To obtain high quality of drinking water free from biocontaminants is especially important issue. A new strategy employing smectic liquid-crystalline ionic membranes exhibiting 2D structures of layered nanochannels for water treatment is proposed for efficient virus removal and sufficient water flux. The smectic A (SmA) liquid-crystalline membranes obtained by in situ polymerization of an ionic mesogenic monomer are examined for removal of three distinct viruses with small size: Qß bacteriophage, MS2 bacteriophage, and Aichi virus. The semi-bilayer structure of the SmA significantly obstructs the virus penetration with an average log reduction value of 7.3 log10 or the equivalent of reducing 18 million viruses down to 1. Furthermore, the layered nanochannels of the SmA liquid crystal allow efficient water permeation compared to other types of liquid-crystalline membrane consisting of nanopores.


Assuntos
Cristais Líquidos , Nanoestruturas , Vírus , Purificação da Água , Membranas Artificiais
7.
ACS Macro Lett ; 8(1): 24-30, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35619406

RESUMO

Here we report columnar liquid-crystalline (LC) nanostructured membranes that highly remove viruses and show sufficient water permeation. These membranes were prepared by employing two-component liquid crystals that exhibit tetragonal columnar phases. The membranes exhibited virus rejection values of >99.99% (log10 reduction value (LRV) > 4) and water flux ranging from 19 to 61 L m-2 h-1 (operation pressure: 0.3 MPa). These membranes were fabricated by photopolymerization of a fan-shaped diol molecule and imidazolium ionic liquid mixture, followed by subsequent removal of the ionic liquid. The rejection values and water flux depend on the fraction of ionic liquid. These results show new design strategies of materials for the water treatment nanostructured membranes that remove pathogens and contaminants.

8.
Phys Med Rehabil Clin N Am ; 30(1): 155-170, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30470419

RESUMO

Neurosensory deficits after traumatic brain injury can frequently lead to disability; therefore, diagnosis and treatment are important. Posttraumatic headaches typically resemble migraines and are managed similarly, but adjuvant physical therapy may be beneficial. Sleep-related issues are treated pharmacologically based on the specific sleep-related complaint. Fatigue is difficult to treat; cognitive behavioral therapy and aquatic therapy can be beneficial. Additionally, methylphenidate and modafinil have been used. Peripheral and central vestibular dysfunction causes dizziness and balance dysfunction, and the mainstay of treatment is vestibular physical therapy. Visual dysfunction incorporates numerous different diagnoses, which are frequently treated with specific rehabilitation programs.


Assuntos
Lesões Encefálicas Traumáticas/reabilitação , Traumatismo Múltiplo/reabilitação , Transtornos de Sensação/etiologia , Transtornos de Sensação/reabilitação , Veteranos , Lesões Encefálicas Traumáticas/complicações , Lesões Encefálicas Traumáticas/diagnóstico , Gerenciamento Clínico , Humanos , Traumatismo Múltiplo/complicações , Traumatismo Múltiplo/diagnóstico , Transtornos de Sensação/diagnóstico
9.
Adv Healthc Mater ; 6(14)2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28485109

RESUMO

To remove viruses from water, the use of self-assembling liquid crystals is presented as a novel method for the synthesis of membranes with a regular pore size (below 1 nm) and controlled pore structures. Nanostructured bicontinuous cubic liquid-crystalline (LC) thin films are photopolymerized onto a polysulfone support layer. It is found that these membranes reject the virus, Qß bacteriophage (≈20 nm diameter) by >99.9999%. Prepressurization of the membrane appears to enhance their virus rejection properties. This is the first example of nanostructured LC membranes that are used for virus rejection, for which they show great potential.


Assuntos
Allolevivirus/química , Cristais Líquidos/química , Membranas Artificiais , Nanoestruturas/química
10.
Am J Med Qual ; 31(3): 209-16, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-25583877

RESUMO

Effective quality improvement (QI) education should improve patient care, but many curriculum studies do not include clinical measures. The research team evaluated the prevalence of QI curricula with clinical measures and their association with several curricular features. MEDLINE, Embase, CINAHL, and ERIC were searched through December 31, 2013. Study selection and data extraction were completed by pairs of reviewers. Of 99 included studies, 11% were randomized, and 53% evaluated clinically relevant measures; 85% were from the United States. The team found that 49% targeted 2 or more health professions, 80% required a QI project, and 65% included coaching. Studies involving interprofessional learners (odds ratio [OR] = 6.55; 95% confidence interval [CI] = 2.71-15.82), QI projects (OR = 13.60; 95% CI = 2.92-63.29), or coaching (OR = 4.38; 95% CI = 1.79-10.74) were more likely to report clinical measures. A little more than half of the published QI curricula studies included clinical measures; they were more likely to include interprofessional learners, QI projects, and coaching.


Assuntos
Educação Médica , Melhoria de Qualidade , Currículo , Humanos , Melhoria de Qualidade/organização & administração , Qualidade da Assistência à Saúde/organização & administração
11.
Autophagy ; 11(7): 1025-36, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26043942

RESUMO

A homozygous mutation in the DST (dystonin) gene causes a newly identified lethal form of hereditary sensory and autonomic neuropathy in humans (HSAN-VI). DST loss of function similarly leads to sensory neuron degeneration and severe ataxia in dystonia musculorum (Dst(dt)) mice. DST is involved in maintaining cytoskeletal integrity and intracellular transport. As autophagy is highly reliant upon stable microtubules and motor proteins, we assessed the influence of DST loss of function on autophagy using the Dst(dt-Tg4) mouse model. Electron microscopy (EM) revealed an accumulation of autophagosomes in sensory neurons from these mice. Furthermore, we demonstrated that the autophagic flux was impaired. Levels of LC3-II, a marker of autophagosomes, were elevated. Consequently, Dst(dt-Tg4) sensory neurons displayed impaired protein turnover of autophagosome substrate SQTSM1/p62 and of polyubiquitinated proteins. Interestingly, in a previously described Dst(dt-Tg4) mouse model that is partially rescued by neuronal specific expression of the DST-A2 isoform, autophagosomes, autolysosomes, and damaged organelles were reduced when compared to Dst(dt-Tg4) mutant mice. LC3-II, SQTSM1, polyubiquitinated proteins and autophagic flux were also restored to wild-type levels in the rescued mice. Finally, a significant decrease in DNAIC1 (dynein, axonemal, intermediate chain 1; the mouse ortholog of human DNAI1), a member of the DMC (dynein/dynactin motor complex), was noted in Dst(dt-Tg4) dorsal root ganglia and sensory neurons. Thus, DST-A2 loss of function perturbs late stages of autophagy, and dysfunctional autophagy at least partially underlies Dst(dt) pathogenesis. We therefore conclude that the DST-A2 isoform normally facilitates autophagy within sensory neurons to maintain cellular homeostasis.


Assuntos
Autofagia , Distonia/patologia , Células Receptoras Sensoriais/patologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas de Transporte/genética , Proteínas do Citoesqueleto/genética , Complexo Dinactina , Distonia/metabolismo , Distonina , Proteínas de Choque Térmico/metabolismo , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/metabolismo , Proteínas do Tecido Nervoso/genética , Fagossomos/metabolismo , Fagossomos/ultraestrutura , Células Receptoras Sensoriais/metabolismo , Células Receptoras Sensoriais/ultraestrutura , Proteína Sequestossoma-1
12.
Int J Rheumatol ; 2014: 523897, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25197282

RESUMO

Objective. To evaluate whether hyperuricemia is a risk factor for cardiovascular disease (CVD) in patients with rheumatoid arthritis (RA). Methods. A population-based inception cohort of patients diagnosed between 1980 and 2007 with adult-onset RA was assembled. A comparison cohort of age- and sex-matched subjects without RA (non-RA) was also assembled. All clinically obtained uric acid values were collected. CVD and noncardiac vascular events were recorded for each patient. Cox proportional hazards models were used to assess the impact of hyperuricemia on development of CVD, mortality, and noncardiac vascular disease. Results. In patients without RA, hyperuricemia was associated with heart failure (HR: 1.95; 95% CI: 1.13-3.39) and CVD (HR: 1.59; 95% CI: 0.99-2.55). In patients with RA, hyperuricemia was not significantly associated with CVD but was significantly associated with peripheral arterial events (HR: 2.52; 95% CI: 1.17-5.42). Hyperuricemia appeared to be more strongly associated with mortality among RA patients (HR: 1.96; 95% CI: 1.45-2.65) than among the non-RA subjects (HR: 1.57; 95% CI: 1.09-2.24). Conclusion. In patients with RA, hyperuricemia was a significant predictor of peripheral arterial events and mortality but not of CVD.

13.
Magn Reson Imaging ; 32(10): 1290-6, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25111625

RESUMO

OBJECTIVE: Quantitative T1ρ MRI has been suggested as a promising tool to detect changes in cartilage composition that are characteristic of cartilage damage and degeneration. The objective of this study was to evaluate the capability of MR T1ρ to detect cartilage lesions as evaluated by arthroscopy in acutely ACL-injured knees and to compare with the Whole-Organ Magnetic Resonance Imaging Score (WORMS) using clinical standard MRI. METHOD: Ten healthy controls (mean age 35) with no ACL injury or history of osteoarthritis (OA) and 10 patients with acute ACL injuries (mean age 39) were scanned at 3 Tesla (3T). ACL patients underwent ACL reconstruction, where focal lesions were graded according to an Outerbridge grading system during arthroscopic evaluation. Normalized MR T1ρ values (T1ρ z-scores normalized to control values in matched regions) in full thickness, and superficial and deep layers of cartilage were compared between defined sub-compartments with and without focal lesions. Intraclass (ICC) correlation and the root mean square coefficient of variation (RMS-CV) were performed to evaluate the inter-observer reproducibility of T1ρ quantification. Sub-compartments of cartilage were also evaluated using WORMS scoring and compared to their Outerbridge score respectively. RESULTS: The inter-observer ICC and the RMS-CV of the sub-compartment T1ρ quantification were 0.961 and 3.9%, respectively. The average T1ρ z-scores were significantly increased in sub-compartments with focal lesions compared to those without focal lesions and to the control cohort (p<0.05). CONCLUSION: Our results indicate that T1ρ provided a better diagnostic capability than clinical standard MRI grading in detecting focal cartilage abnormalities after acute injuries. Quantitative MRI may have great potential in detecting cartilage abnormalities and degeneration non-invasively, which are occult with standard morphological MRI.


Assuntos
Lesões do Ligamento Cruzado Anterior , Artroscopia , Cartilagem Articular/patologia , Imageamento por Ressonância Magnética , Adulto , Índice de Massa Corporal , Estudos de Casos e Controles , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Joelho/patologia , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Reprodutibilidade dos Testes
14.
Ann Biomed Eng ; 41(12): 2553-64, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23887879

RESUMO

In this technique development study, high-resolution peripheral quantitative computed tomography (HR-pQCT) was applied to non-invasively image and quantify 3D joint space morphology of the wrist and metacarpophalangeal (MCP) joints of patients with rheumatoid arthritis (RA). HR-pQCT imaging (82 µm voxel-size) of the dominant hand was performed in patients with diagnosed rheumatoid arthritis (RA, N = 16, age: 52.6 ± 12.8) and healthy controls (CTRL, N = 7, age: 50.1 ± 15.0). An automated computer algorithm was developed to segment wrist and MCP joint spaces. The 3D distance transformation method was applied to spatially map joint space width, and summarized by the mean joint space width (JSW), minimal and maximal JSW (JSW.MIN, JSW.MAX), asymmetry (JSW.AS), and distribution (JSW.SD)-a measure of joint space heterogeneity. In vivo precision was determined for each measure by calculating the smallest detectable difference (SDD) and root mean square coefficient of variation (RMSCV%) of repeat scans. Qualitatively, HR-pQCT images and pseudo-color JSW maps showed global joint space narrowing, as well as regional and focal abnormalities in RA patients. In patients with radiographic JSN at an MCP, JSW.SD was two-fold greater vs. CTRL (p < 0.01), and JSW.MIN was more than two-fold lower (p < 0.001). Similarly, JSW.SD was significantly greater in the wrist of RA patients vs. CTRL (p < 0.05). In vivo precision was highest for JSW (SDD: 100 µm, RMSCV: 2.1%) while the SDD for JSW.MIN and JSW.SD were 370 and 110 µm, respectively. This study suggests that in vivo quantification of 3D joint space morphology from HR-pQCT, could improve early detection of joint damage in rheumatological diseases.


Assuntos
Artrite Reumatoide/diagnóstico por imagem , Articulação Metacarpofalângica/diagnóstico por imagem , Punho/diagnóstico por imagem , Adulto , Idoso , Artrite Reumatoide/patologia , Feminino , Humanos , Masculino , Articulação Metacarpofalângica/patologia , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios X , Punho/patologia
15.
J Magn Reson Imaging ; 35(1): 117-24, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22190287

RESUMO

PURPOSE: To compare vertebral bone marrow fat content quantified with proton MR spectroscopy ((1)H-MRS) with the volume of abdominal adipose tissue, lumbar spine volumetric bone mineral density (vBMD), and blood biomarkers in postmenopausal women with and without type 2 diabetes mellitus (T2DM). MATERIALS AND METHODS: Thirteen postmenopausal women with T2DM and 13 age- and body mass index-matched healthy controls were included in this study. All subjects underwent (1)H-MRS of L1-L3 to quantify vertebral bone marrow fat content (FC) and unsaturated lipid fraction (ULF). Quantitative computed tomography (QCT) was performed to assess vBMD of L1-L3. The volumes of abdominal subcutaneous/visceral/total adipose tissue were determined from the QCT images and adjusted for abdominal body volume (SAT(adj)/VAT(adj)/TAT(adj)). Fasting blood tests included plasma glucose and HbA1c. RESULTS: Mean FC showed an inverse correlation with vBMD (r = -0.452; P < 0.05) in the whole study population. While mean FC was similar in the diabetic women and healthy controls (69.3 ± 7.5% versus 67.5 ± 6.1%; P > 0.05), mean ULF was significantly lower in the diabetic group (6.7 ± 1.0% versus 7.9 ± 1.6%; P < 0.05). SAT(adj) and TAT(adj) correlated significantly with mean FC in the whole study population (r = 0.538 and r = 0.466; P < 0.05). In contrast to the control group, significant correlations of mean FC with VAT(adj) and HbA1c were observed in the diabetic group (r = 0.642 and r = 0.825; P < 0.05). CONCLUSION: This study demonstrated that vertebral bone marrow fat content correlates significantly with SAT(adj), TAT(adj), and lumbar spine vBMD in postmenopausal women with and without T2DM, but with VAT(adj) and HbA1c only in women with T2DM.


Assuntos
Gordura Abdominal/patologia , Tecido Adiposo/patologia , Biomarcadores/metabolismo , Medula Óssea/patologia , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/terapia , Vértebras Lombares/metabolismo , Idoso , Biomarcadores/sangue , Densidade Óssea , Estudos de Casos e Controles , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Vértebras Lombares/patologia , Espectroscopia de Ressonância Magnética/métodos , Pessoa de Meia-Idade , Pós-Menopausa , Reprodutibilidade dos Testes , Tomografia Computadorizada por Raios X/métodos
16.
Radiology ; 261(2): 507-15, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21900614

RESUMO

PURPOSE: To determine the frequency of degenerative knee morphologic abnormalities in asymptomatic individuals by using 3-T magnetic resonance (MR) imaging and to investigate the characteristics and evolution of cartilage T2 values in relation to morphologic abnormalities with a longitudinal study. MATERIALS AND METHODS: The study was approved by the institutional review board and was compliant with HIPAA. Ninety-five asymptomatic subjects aged 45-78 years who were free of risk factors for osteoarthritis (OA) were selected from the Osteoarthritis Initiative normal control cohort and examined with radiography and 3-T MR imaging. Data obtained at both baseline and 2-year follow-up were analyzed. OA-related knee abnormalities were analyzed by using the whole-organ MR imaging score (WORMS). Cartilage T2 maps were generated by using sagittal two-dimensional multiecho spin-echo images of the right knee. Statistical significance was determined with the Student t test, the paired t test, a mixed random effects model, one-way analysis of variance, and a multiple linear regression model. RESULTS: Knee abnormalities were identified with a high frequency (90% at baseline and 92% at 2-year follow-up). The prevalence of hyaline cartilage lesions was particularly high (86% at baseline and 84% at follow-up). A significant longitudinal increase in T2 was detected in the tibiofemoral cartilage but not the patellofemoral cartilage (P = .0072). The longitudinal change in T2 was significantly associated with worsening of the cartilage WORMS (P = .038). CONCLUSION: Asymptomatic subjects have a high frequency of OA-related morphologic abnormalities. A significant increase in tibiofemoral cartilage T2 was detected over the 2-year period. A greater increase in T2 was associated with increased progression of cartilage morphologic abnormalities.


Assuntos
Cartilagem Articular/patologia , Articulação do Joelho/patologia , Imageamento por Ressonância Magnética/métodos , Osteoartrite do Joelho/patologia , Idoso , Análise de Variância , Cartilagem Articular/fisiopatologia , Avaliação da Deficiência , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Articulação do Joelho/fisiopatologia , Modelos Lineares , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/fisiopatologia , Medição da Dor , Reprodutibilidade dos Testes , Fatores de Risco , Estatísticas não Paramétricas , Inquéritos e Questionários
17.
J Magn Reson Imaging ; 33(4): 974-9, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21448966

RESUMO

PURPOSE: To determine the reproducibility of proton MR spectroscopy ((1) H-MRS) for assessing vertebral bone marrow adiposity at 3 Tesla (T); to evaluate variation of marrow adiposity at different vertebral levels; and to demonstrate the feasibility of using (1) H-MRS at 3T for evaluating marrow adiposity in subjects with low bone density. MATERIALS AND METHODS: Single voxel MRS was acquired at vertebral body L1 to L4 at 3T in 51 postmenopausal females including healthy controls (n = 13) and patients with osteoporosis/osteopenia (n = 38). Marrow fat contents were compared between vertebral levels and between groups using analysis of variance (ANOVA). Six subjects were scanned twice to evaluate technique reproducibility. RESULTS: The average coefficient of variation of vertebral marrow fat content quantification was 1.7%. Marrow fat content significantly increased from L1 to L4. The average fat content was significantly elevated in patients with osteoporosis/osteopenia compared with controls, adjusted for age and body mass index (P < 0.05). CONCLUSION: In vivo MRS at high field strength provides reliable measurement of marrow adiposity with excellent reproducibility and can be a valuable tool for providing complementary information on bone quality and potentially also fracture risk.


Assuntos
Espectroscopia de Ressonância Magnética/métodos , Osteoporose Pós-Menopausa/patologia , Tecido Adiposo/patologia , Idoso , Índice de Massa Corporal , Densidade Óssea , Doenças Ósseas Metabólicas/patologia , Estudos de Coortes , Feminino , Humanos , Processamento de Imagem Assistida por Computador/métodos , Pessoa de Meia-Idade , Osteoporose/patologia , Osteoporose Pós-Menopausa/diagnóstico , Reprodutibilidade dos Testes , Coluna Vertebral/patologia
18.
Arthroscopy ; 27(1): 65-76, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21035995

RESUMO

PURPOSE: To quantitate bone marrow edema-like lesions (BMELs) and the radiologic properties of cartilage in knees with acute anterior cruciate ligament (ACL) injuries using T(1ρ) magnetic resonance imaging over a 1-year period. METHODS: Nine patients with ACL injuries were studied. Magnetic resonance imaging scans were acquired within 8 weeks of the injury, after which ACL reconstruction surgery was performed. Images were then acquired 0.5, 6, and 12 months after reconstructions. The volume and signal intensity of BMELs were quantified at baseline and follow-up examinations. T(1ρ) values were quantified in cartilage overlying the BMEL (OC) and compared with surrounding cartilage at all time points. RESULTS: BMELs were most commonly found in the lateral tibia and lateral femoral condyle. Nearly 50% of BMELs resolved over a 1-year period. The T(1ρ) values of the OC in the lateral tibia, medial tibia, and medial femoral condyle were elevated compared with respective regions in surrounding cartilage at all time points; the difference was significant only in the lateral tibia (P < .05). The opposite results were found in the lateral femoral condyle. For the medial tibia and medial femoral condyle, none of the time periods was significantly different. The percent increase in T(1ρ) values of OC in the lateral tibia was significantly correlated with BMEL volume (r = 0.74, P < .05). At 1 year, the OC in the lateral tibia, medial tibia, and medial femoral condyle showed increased T(1ρ) values despite improvement of BMEL. CONCLUSIONS: In patients after ACL tear and reconstruction, (1) the cartilage overlying BMEL in the lateral tibia experiences persistent T(1ρ) signal changes immediately after acute injuries and at 1-year follow-up despite BMEL improvement, (2) the superficial layers of the overlying cartilage show greater matrix damage than the deep layers, and (3) the volume of the BMEL may predict the severity of the overlying matrix's damage in the lateral tibia. T(1ρ) is capable of quantitatively and noninvasively monitoring this damage and detecting early cartilage changes in the lateral tibia over time. LEVEL OF EVIDENCE: Level IV, therapeutic case series.


Assuntos
Ligamento Cruzado Anterior/cirurgia , Medula Óssea/patologia , Cartilagem Articular/patologia , Contusões/patologia , Traumatismos do Joelho/patologia , Imageamento por Ressonância Magnética/métodos , Adulto , Lesões do Ligamento Cruzado Anterior , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Radiology ; 258(2): 505-14, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21177392

RESUMO

PURPOSE: To longitudinally evaluate cartilage matrix changes by using magnetic resonance (MR) imaging T1(ρ) (T1 relaxation time in rotating frame) and T2 quantification and to study the relationship between meniscal damage and cartilage degeneration in anterior cruciate ligament (ACL)-reconstructed knees. MATERIALS AND METHODS: This was an institutional review board-approved, HIPAA-compliant study. Informed consent was obtained. Twelve patients with acute ACL injuries were imaged with 3.0-T MR imaging at baseline (after injury and prior to ACL reconstruction) and 1 year after ACL reconstruction. Ten age-matched healthy subjects were studied as controls. Cartilage T1(ρ) and T2 were quantified in full thickness, superficial, and deep layers of defined subcompartments at baseline and follow-up in ACL-injured knees and were compared with measures acquired in matched regions of control knees. Meniscal lesions were graded by using modified subscores of the Whole-Organ Magnetic Resonance Imaging Score system. RESULTS: T1(ρ) values of the posterolateral tibial cartilage in ACL-injured knees were significantly elevated at baseline compared with T1(ρ)values of control knees and were not fully recovered at 1-year follow-up. T1(ρ) values of weight-bearing medial femorotibial cartilage in ACL-injured knees were significantly elevated at 1-year follow-up compared with those of control knees. No significant differences in T2 values between ACL-injured and control knees were found. Patients with lesions in the posterior horn of the medial meniscus showed a greater increase of T1(ρ) and T2 from baseline to follow-up in adjacent cartilage than patients without lesions in the medial meniscus. CONCLUSION: Quantitative MR imaging T1(ρ) and T2 enable detection of changes in the cartilage matrix of ACL-reconstructed knees as early as 1 year after ACL reconstruction.


Assuntos
Lesões do Ligamento Cruzado Anterior , Ligamento Cruzado Anterior/cirurgia , Imageamento por Ressonância Magnética/métodos , Meniscos Tibiais/patologia , Adulto , Análise de Variância , Estudos de Casos e Controles , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Suporte de Carga
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