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1.
Osteoarthritis Cartilage ; 29(5): 718-727, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33577958

RESUMO

OBJECTIVE: The vascularization of subchondral bone plays a significant role in the progression of knee osteoarthritis (OA). Treatment with platelet-rich plasma (PRP) has positive effects on cartilage lesions. However, PRP's efficacy for subchondral bone marrow lesions and the relationship of these lesions to cartilage are still undiscovered. Therefore, our aims were first to longitudinally investigate the change in subchondral flow by dynamic contrast enhanced MRI and degeneration of cartilage by MRI T2∗ in an anterior cruciate transection rodent (ACLT) model, and second to examine changes in parameters after intra-articular PRP injection. DESIGN: A 32-week investigation in 18 rats allocated to sham-control, ACLT with normal saline injection (ACLT + NS), and ACLT with PRP injection groups ended with histological evaluation. Another rat was used as a donor of allogenic PRP. RESULTS: Compared to the sham-control group, the ACLT + NS group had higher subchondral blood volume A (0.051, 95% confidence interval: 0.009, 0.092) and lower venous washout kel (-0.030: -0.055, -0.005) from week 4; lower permeability kep from week 18 (-0.954: -1.339, -0.569); higher cartilage T2∗ values (1.803: 1.504, 2.102) reflecting collagen loss beginning at week 10. For the PRP treatment group, subchondral bone marrow A and cartilage T2∗ decreased from week 10. Histological results confirmed and were correlated with the MRI findings. CONCLUSION: Subchondral hyper-perfusion plays a vital role in the pathogenesis of OA and was associated with cartilage degeneration. The efficacy of PRP can be observed from reduced perfusion and MRI T2∗ values.


Assuntos
Medula Óssea/irrigação sanguínea , Medula Óssea/diagnóstico por imagem , Cartilagem Articular/diagnóstico por imagem , Imageamento por Ressonância Magnética , Plasma Rico em Plaquetas , Animais , Volume Sanguíneo , Modelos Animais de Doenças , Injeções Intra-Articulares , Osteoartrite/diagnóstico por imagem , Osteoartrite/terapia , Ratos Sprague-Dawley , Joelho de Quadrúpedes/irrigação sanguínea , Joelho de Quadrúpedes/diagnóstico por imagem
2.
Phys Rev Lett ; 126(20): 201102, 2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34110215

RESUMO

The measurement of the energy spectrum of cosmic ray helium nuclei from 70 GeV to 80 TeV using 4.5 years of data recorded by the Dark Matter Particle Explorer (DAMPE) is reported in this work. A hardening of the spectrum is observed at an energy of about 1.3 TeV, similar to previous observations. In addition, a spectral softening at about 34 TeV is revealed for the first time with large statistics and well controlled systematic uncertainties, with an overall significance of 4.3σ. The DAMPE spectral measurements of both cosmic protons and helium nuclei suggest a particle charge dependent softening energy, although with current uncertainties a dependence on the number of nucleons cannot be ruled out.

3.
Osteoarthritis Cartilage ; 25(6): 976-985, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28011101

RESUMO

OBJECTIVE: Chronic kidney disease (CKD) is characterized by metabolic disturbances in calcium and phosphorus homeostasis as kidney function declines. Alterations in blood perfusion in bone resulting from arteriosclerosis of bone vessels may relate to the progression of CKD. Herein, change in dynamic contrast enhanced (DCE) MRI parameters (A: amplitude, kel: elimination constant, and kep: permeability rate constant) and MRI T2∗ relaxation time of the knee cartilage were measured in a rodent nephrectomy model in order to (1) examine the relationship of peripheral blood perfusion to CKD and (2) demonstrate the feasibility of using DCE-MRI parameters and MRI T2∗ as imaging biomarkers to monitor disease progression. DESIGN: Two groups of male Sprague-Dawley rats received either (1) no intervention or (2) 5/6 nephrectomy. RESULTS: We found that the CKD group (compared with the control group) had lower A and kel values and similar kep value in the lateral and medial articular cartilages beginning at 12 weeks (P < 0.05); statistically significantly higher T2∗ values in the lateral and medial articular cartilages beginning at 18 weeks (P < 0.05); statistically significantly decreased inner luminal diameter of the popliteal artery, and altered structure of the lateral and medial articular cartilages (P < 0.05). CONCLUSION: Perfusion deficiency and CKD may be related. DCE parameters and MRI T2∗ could serve as imaging biomarkers of cartilage degeneration in CKD progression.


Assuntos
Cartilagem Articular/diagnóstico por imagem , Articulação do Joelho/diagnóstico por imagem , Fluxo Sanguíneo Regional , Insuficiência Renal Crônica/diagnóstico por imagem , Animais , Cartilagem Articular/irrigação sanguínea , Modelos Animais de Doenças , Articulação do Joelho/irrigação sanguínea , Imageamento por Ressonância Magnética , Masculino , Nefrectomia , Ratos , Ratos Sprague-Dawley
5.
Osteoarthritis Cartilage ; 24(1): 129-33, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26241778

RESUMO

OBJECTIVE: Although anterior cruciate ligament (ACL) injury is a well-recognized risk factor for developing knee post-traumatic osteoarthritis (PTOA), the process in the patellofemoral (PF) joint after ACL injury is still under-researched. Our aim was to investigate the perfusion changes in PF subchondral bone marrow in the rat ACL transection (ACLX) model of PTOA using dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI). DESIGN: Eighteen male Sprague Dawley rats were randomly separated into three groups (n = 6 each group): a normal control group and groups receiving ACLX and sham-surgery, respectively, in the right knee. Perfusion parameters in the patellar and femoral subchondral bone marrows of all rats were measured on DCE-MRI at 0, 4, 8, and 16 weeks after respective treatment. After the last MRI at week 16, the rats were sacrificed and their right knees were harvested for histologic examination. In addition, to observe the long-term histologic change in PF joints, 9 additional rats (n = 3 in each group) were included and sacrificed at week 32 for histologic examination. RESULTS: In the ACLX group vs the sham and control groups, the perfusion parameters were significantly changed in both patellar and femoral subchondral bone marrows at week 16. Histologic examination revealed cartilage defects in ACLX rats at 32 weeks after surgery. CONCLUSIONS: These data point to a possible functional relationship between subchondral bone marrow perfusion abnormalities and cartilage breakdown in PTOA. Moreover, the perfusion parameters derived from DCE-MRI can potentially serve as biomarkers of early OA.


Assuntos
Lesões do Ligamento Cruzado Anterior , Medula Óssea/irrigação sanguínea , Fêmur/irrigação sanguínea , Osteoartrite do Joelho/fisiopatologia , Patela/irrigação sanguínea , Animais , Meios de Contraste , Traumatismos do Joelho/complicações , Imageamento por Ressonância Magnética , Masculino , Osteoartrite do Joelho/etiologia , Ratos , Ratos Sprague-Dawley
6.
Niger J Clin Pract ; 19(3): 411-3, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27022810

RESUMO

Retrograde jejunal intussusception is a rare disease. A 60-year-old female patient was hospitalized due to vomiting for 2 days, with a history of radical gastrectomy plus esophagus jejunum Rouxs-en-Y. On examination, there was a palpable wax-like mass on the left-hand side underneath the umbilicus. Computerized tomography scan showed a proximal jejunal intussusception. During surgery, the distal jejunum was found set into the proximal jejunum for a length of 30 cm, and bowel necrosis was also observed. The necrotic tube was resected and anastomosis was performed. Four days after the surgery, gastrointestinal function resumed. After a 10-month follow-up, the patient had no discomfort.


Assuntos
Esôfago/cirurgia , Gastrectomia/efeitos adversos , Intussuscepção/cirurgia , Doenças do Jejuno/cirurgia , Jejuno/cirurgia , Síndromes Pós-Gastrectomia/cirurgia , Tomografia Computadorizada por Raios X , Anastomose em-Y de Roux/métodos , Feminino , Gastrectomia/métodos , Humanos , Intussuscepção/diagnóstico por imagem , Intussuscepção/etiologia , Doenças do Jejuno/etiologia , Pessoa de Meia-Idade , Síndromes Pós-Gastrectomia/etiologia , Reoperação
7.
Genet Mol Res ; 14(3): 11362-70, 2015 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-26436377

RESUMO

Recent studies have revealed that the inflammatory process plays a role in the pathogenesis of osteoarthritis (OA). The S100 family and receptor for advanced glycation end products (RAGE) participate in regulating inflammation, even in the production of matrix metalloproteinases (MMPs). MMP-1 degrades cartilage, which may result in OA development. Moreover, polymorphisms in RAGE, S100A8, and MMP-1 have a marked effect on ligand binding and transcription regulating. In this study, we investigated the potential genetic contribution of the RAGE, S100A8, and MMP-1 genes to OA. We performed a matched case-control association study and genotyped OA patients and healthy controls, who were analyzed by polymerase chain reaction-restriction fragment length polymorphism assays. A total of 207 patients were diagnosed with knee OA and underwent total knee replacement. The control group included 207 individuals who had standard X-rays of the knee joints to confirm K/L < 2 and were matched by age and gender. Single-nucleotide polymorphisms in RAGE (-429T/C, -374T/A, and 557G/A), S100A8 (rs3795391A/G), and MMP-1 (-1607 1G/2G, -755G/T, and -519A/G) were evaluated. RAGE -374T/A, S100A8 rs3795391A/G, MMP-1 -1607 1G/2G, -755G/T, and -519A/G showed no significant difference between OA patients and healthy controls. RAGE -429T/C and 557G/A showed a significant association between OA patients and healthy controls (P = 0.016 and 0.047, respectively). In haplotype analyses, no RAGE and MMP-1 haplotypes showed associations with OA. Our results suggest that the investigated polymorphism in the RAGE gene play a role in OA in the Han Chinese population.


Assuntos
Povo Asiático/genética , Etnicidade/genética , Predisposição Genética para Doença , Osteoartrite do Joelho/genética , Polimorfismo de Nucleotídeo Único/genética , Receptor para Produtos Finais de Glicação Avançada/genética , Índice de Gravidade de Doença , Idoso , Calgranulina A/genética , Estudos de Casos e Controles , Feminino , Estudos de Associação Genética , Haplótipos/genética , Humanos , Masculino , Metaloproteinase 1 da Matriz/genética
8.
Phys Rev Lett ; 110(13): 131802, 2013 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-23581310

RESUMO

The beauty to up quark coupling constant |V(ub)| can be extracted from B → ρ e+ ν(e) combined with the form factors for D → K* e+ ν(e) and B → V ℓ+ ℓ- and D → ρ e+ ν(e). Using the entire CLEO-c ψ(3770) → DD event sample, corresponding to an integrated luminosity of 818 pb(-1) and approximately 5.4×10(6) DD events, we measure the form factors for the decays D0 → ρ- e+ ν(e) and D+ → ρ0 e+ ν(e) for the first time and the branching fractions with improved precision. A four-dimensional unbinned maximum likelihood fit determines the form factor ratios to be V(0)/A1(0)=1.48±0.15±0.05 and A2(0)/A1(0)=0.83±0.11±0.04. Assuming Cabibbo-Kobayashi-Maskawa unitarity, the known D meson lifetimes, and our measured branching fractions we obtain the form factor normalizations A1(0), A2(0), and V(0). We also present a measurement of the branching fraction for D+ → ω e+ ν(e) with improved precision.

9.
Eur Cell Mater ; 26: 179-94; discussion 194, 2013 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-24122653

RESUMO

Three-dimensional (3D) cellular spheroids have recently emerged as a new trend to replace suspended single cells in modern cell-based therapies because of their greater regeneration capacities in vitro. They may lose the 3D structure during a change of microenvironment, which poses challenges to their translation in vivo. Besides, the conventional microporous scaffolds may have difficulty in accommodating these relatively large spheroids. Here we revealed a novel design of microenvironment for delivering and sustaining the 3D spheroids. Biodegradable scaffolds with macroporosity to accommodate mesenchymal stem cell (MSC) spheroids were made by solid freeform fabrication (SFF) from the solution of poly(D,L-lactide-co-glycolide). Their internal surface was modified with chitosan following air plasma treatment in order to preserve the morphology of the spheroids. It was demonstrated that human MSC spheroids loaded in SFF scaffolds produced a significantly larger amount of cartilage-associated extracellular matrix in vitro and in NOD/SCID mice compared to single cells in the same scaffolds. Implantation of MSC spheroid-loaded scaffolds into the chondral defects of rabbit knees showed superior cartilage regeneration. This study establishes new perspectives in designing the spheroid-sustaining microenvironment within a tissue engineering scaffold for in vivo applications.


Assuntos
Cartilagem/fisiologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Regeneração , Esferoides Celulares/efeitos dos fármacos , Alicerces Teciduais/química , Adulto , Animais , Plásticos Biodegradáveis/química , Plásticos Biodegradáveis/farmacologia , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Microambiente Celular/efeitos dos fármacos , Quitosana/química , Quitosana/farmacologia , Matriz Extracelular/efeitos dos fármacos , Feminino , Humanos , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais/fisiologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Poliglactina 910/química , Poliglactina 910/farmacologia , Coelhos , Esferoides Celulares/fisiologia
10.
Ultraschall Med ; 33(7): E158-E165, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23238801

RESUMO

PURPOSE: To retrospectively determine the reproducibility and performance of a quantitative measurement for cam-type femoroacetabular impingement (FAI) designated as the anterior femoral distance (AFD) of the femoral head-neck junction identified at ultrasonography (US). MATERIALS AND METHODS: 72 patients with clinically suspected FAI were retrospectively evaluated, and US studies were performed during a 20-month period. Of these, we selected 53 patients who underwent subsequent magnetic resonance (MR) arthrography and had adequate recorded US images. All the longitudinal US images of the anterior and anterosuperior contours of the femoral head-neck junction were recorded by a radiologist. 33 of these US images were also recorded by a technician. An alpha angle of > 55° on MR arthrography was indicative of cam-type FAI. Two independent radiology residents blinded to the clinical data and MR arthrography measured the maximal femoral head-neck overgrowth defined as the AFD on US (AFD-US). Reproducibility was assessed using intra-class correlation coefficients (ICCs) and Bland-Altman plots, and diagnostic performance was assessed using receiver operating characteristic (ROC) analysis. RESULTS: AFD-US showed high intra- and inter-rater agreement (ICC = 0.913 - 0.968) in all measurements and good reproducibility among different operators in the anterior contour measurements (ICC = 0.881) but not in the anterosuperior contour measurements (ICC = 0.196). An AFD-US cut-off value of 4.0 mm in the anterior contour yielded the greatest sensitivity (80.9 %) and specificity (87.5 %) for the diagnosis of cam-type FAI by ROC analysis. CONCLUSION: AFD-US of the anterior contour of the femoral head-neck junction is helpful in diagnosing cam-type FAI.


Assuntos
Artrografia/métodos , Impacto Femoroacetabular/diagnóstico , Cabeça do Fêmur/patologia , Colo do Fêmur/patologia , Interpretação de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Ultrassonografia/métodos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Sensibilidade e Especificidade , Adulto Jovem
11.
Ultraschall Med ; 33(5): 447-54, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22161618

RESUMO

PURPOSE: We analysed the ultrasonographic (US) features of atypical ductal hyperplasia (ADH) of the breast diagnosed by US-guided core needle biopsy (CNB) with the aim of identifying factors that affect the underestimation of ADH. MATERIALS AND METHODS: A total of 134 ADH lesions sampled by US-guided CNB were reviewed retrospectively. All lesions were evaluated for pattern, size, lesion characteristics and margins, and the corresponding surgical outcome or imaging follow-up was obtained. Each patient's clinical and radiological features were analysed to identify factors involved in ADH underestimation. RESULTS: The prevalence of malignancy in each pattern of lesions following surgical excision was 32/81 (40%) for solid masses, 14/31 (45%) for ductal patterns, 5/17 (29%) for complex cystic lesions and 2/5 (40%) for architectural distortions. Based on the results of surgical and US follow-up, none of the category 3 lesions was proven to be a malignancy. Malignancy was found in 17 (21%) of the 80 BI-RADS (Breast Imaging Reporting and Data System) category 4a lesions, 20 (74%) of the 27 category 4b lesions, 12 (92%) of the 13 category 4c lesions, and four (100%) of the four category 5 lesions. Lesions with a higher US assessment category, lacking circumscribed margins, or a mammographic finding of suspected malignancy were all significantly associated with underestimation (p < 0.05 for each). CONCLUSION: US is useful in evaluating ADH lesions and in clarifying the indication for biopsy of these lesions. Familiarity with the frequency associated with malignancy for each feature will improve the utility of US in the work-up of these breast abnormalities.


Assuntos
Biópsia com Agulha de Grande Calibre/métodos , Interpretação de Imagem Assistida por Computador/métodos , Glândulas Mamárias Humanas/patologia , Ultrassonografia de Intervenção/métodos , Ultrassonografia Mamária/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Calcinose , Diagnóstico Diferencial , Feminino , Doença da Mama Fibrocística/diagnóstico por imagem , Doença da Mama Fibrocística/patologia , Predisposição Genética para Doença , Humanos , Hiperplasia/diagnóstico por imagem , Hiperplasia/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade
12.
Osteoarthritis Cartilage ; 18(1): 54-60, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19761884

RESUMO

OBJECTIVE: The purpose of this study was to investigate whether the effect of treatment with hyaluronic acid (HA) on cartilage in osteoarthritis (OA) can be determined by measuring the magnetic resonance (MR) T2 value of cartilage in an anterior cruciate ligament transection (ACLX) animal model. METHOD: Eighteen male Sprague Dawley rats were separated randomly into three groups (n=6 for each group). Group 1 was given ACLX and intra-articular (IA) normal saline (NS) injection (ACLX+NS), group 2 was given ACLX and IA HA injection (ACLX+HA), and group 3 was the sham control. The ACLX+NS and ACLX+HA groups received ACLX on the right knee at 8 weeks of age and were then treated with IA NS or HA injection once a week, respectively, for 4 weeks starting at 13 weeks of age. In the sham-control group, the right knee joint was opened surgically but ACLX was not performed at 8 weeks of age. MR T2 measurements were obtained on all rats at 8, 12, and 21 weeks of age, and histological Mankin scoring was performed at 21 weeks of age. RESULTS: Five weeks after the 4-week treatment, the MR T2 value of the ACLX right knee cartilage was significantly lower in ACLX+HA (29.58+/-1.12ms) than in ACLX+NS (32.04+/-1.39ms) (P<0.05). Five weeks after the 4-week treatment, the Mankin score of the ACLX right knee was significantly lower in ACLX+HA (3.3+/-0.81) than in ACLX+NS (7.3+/-1.03) (P<0.001). The T2 value was significantly and positively correlated with the Mankin score in the ACLX+NS (rho=0.77, P<0.05) and ACLX+HA (rho=0.69, P<0.05) groups. CONCLUSION: This study demonstrates the feasibility of quantitative MR T2 measurement in the early assessment of HA treatment efficiency in a cartilage degeneration model.


Assuntos
Adjuvantes Imunológicos/uso terapêutico , Lesões do Ligamento Cruzado Anterior , Cartilagem Articular/patologia , Ácido Hialurônico/uso terapêutico , Osteoartrite do Joelho/tratamento farmacológico , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Animais , Ligamento Cruzado Anterior/cirurgia , Artrite Experimental/patologia , Cartilagem Articular/efeitos dos fármacos , Modelos Animais de Doenças , Ácido Hialurônico/administração & dosagem , Ácido Hialurônico/farmacologia , Injeções Intra-Articulares , Imageamento por Ressonância Magnética/métodos , Masculino , Osteoartrite do Joelho/patologia , Ratos , Ratos Sprague-Dawley
13.
Osteoarthritis Cartilage ; 18(9): 1192-202, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20510383

RESUMO

OBJECTIVE: To study the effects of oral glucosamine sulfate on the development of osteoarthritis (OA) and to examine concomitant changes in the nociceptive behavior of rats. METHODS: OA was induced in Wistar rats by anterior cruciate ligament transection (ACLT) of the right knee; the left knee was untreated. The OA+glucosamine group received oral glucosamine sulfate (250 mg/kg/day) in a 2-g wafer once a day for 10 consecutive weeks starting at week 5 after ACLT. The OA group was treated as above with 2-g wafers (placebo). The control group of naïve rats received 2-g wafers only. The glucosamine alone group comprised naïve rats receiving glucosamine sulfate only. Nociceptive behavior (mechanical allodynia and weight-bearing distribution of hind paws) during OA development was analyzed pre- and 3, 6, 9, 12, 15, and 18 weeks post-ACLT. Macroscopic and histologic studies were then performed on the cartilage and synovia. Immunohistochemical analysis was performed to examine the effect of glucosamine on expression of mitogen-activated protein kinases (MAPKs) in the articular cartilage chondrocytes. RESULTS: OA rats receiving glucosamine showed a significantly lower degree of cartilage degeneration than the rats receiving placebo. Glucosamine treatment also suppressed synovitis. Mechanical allodynia and weight-bearing distribution studies showed significant improvement in the OA+glucosamine group as compared to the OA group. Moreover, glucosamine attenuated p38 and c-Jun N-terminal kinase (JNK) but increased extracellular signal-regulated kinase 1/2 (ERK) expression in OA-affected cartilage. CONCLUSION: Our results indicate that treatment with oral glucosamine sulfate in a rat OA model (1) attenuates the development of OA, (2) concomitantly reduces nociception, and (3) modulates chondrocyte metabolism, possibly through inhibition of cell p38 and JNK and increase of ERK expression.


Assuntos
Cartilagem Articular/patologia , Condrócitos/efeitos dos fármacos , Condrócitos/enzimologia , Glucosamina/farmacologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Osteoartrite do Joelho/patologia , Administração Oral , Animais , Comportamento Animal/efeitos dos fármacos , Cartilagem Articular/efeitos dos fármacos , Modelos Animais de Doenças , Lateralidade Funcional/efeitos dos fármacos , Imuno-Histoquímica , Articulação do Joelho/patologia , Nociceptores/efeitos dos fármacos , Osteoartrite do Joelho/tratamento farmacológico , Medição da Dor/métodos , Ratos , Ratos Wistar , Membrana Sinovial/patologia , Suporte de Carga/fisiologia
14.
Osteoarthritis Cartilage ; 17(8): 988-94, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19332176

RESUMO

OBJECTIVE: The magnetic resonance (MR) T2 value of the cartilage, which has been shown in the articular cartilage to correlate with collagen fiber orientation and water content, may be helpful for early detection of chondropathy. However, the measurement and significance of MR T2 value for knee meniscus have not been well established. The purpose of this study was to investigate whether the MR T2 values in the diverse zones of the posterior horn of the knee meniscus differ between sexes in a young healthy population. METHOD: Twenty healthy volunteers, 10 men and 10 women (aged from 22 to 32 years), were enrolled for MR imaging of the right knee menisci. The T2 values of the posterior horns of the medial and lateral knee menisci were measured for the white zone, red/white zone, and red zone on images acquired with fat-suppressed multislice turbo spin-echo sequence at 3.0 T. RESULTS: The T2 value, with medial and lateral menisci considered together, increased significantly from the inner white zone (T2=8.02+/-0.60 ms), to the red/white zone (T2=8.78+/-0.99 ms), and to the outer red zone (T2=12.22+/-0.92 ms) of the posterior horns of the menisci (P<0.001). A generalized estimating equation method and multiple linear regression model showed that the T2 values averaged for the medial and lateral menisci together in the red and red/white zones were significantly lower in men than in women by 1.320 ms (P=0.002) and 0.865 ms (P<0.001), respectively, while the white zone showed no significant difference (P=0.694) between men (8.08+/-0.63 ms) and women (7.98+/-0.60 ms). CONCLUSION: Zonal and sex differences in the MR T2 values in the posterior horns of the knee menisci exist in the young healthy population. These differences may be associated with sex differences in the occurrence of knee osteoarthritis.


Assuntos
Cartilagem Articular/patologia , Articulação do Joelho/patologia , Osteoartrite do Joelho/patologia , Adulto , Cartilagem Articular/fisiologia , Estudos de Viabilidade , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Meniscos Tibiais/patologia , Meniscos Tibiais/fisiologia , Osteoartrite do Joelho/fisiopatologia , Valores de Referência , Fatores Sexuais , Adulto Jovem
15.
Osteoarthritis Cartilage ; 17(4): 441-7, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18990590

RESUMO

OBJECTIVE: Both animal and human studies using magnetic resonance imaging (MRI) show that cartilage degeneration increases the T2 value. However, it is unclear whether the T2 value correlates linearly with water content in cartilage with osteoarthritis. The purpose of this study was to investigate the relationship between the T2 value and water content using an animal model of cartilage injury measured at 4.7 T. DESIGN: Thirty Sprague Dawley rats were randomly separated into three groups (n=10 for each group). Group 1 rats were not operated on (control). Group 2 rats received a sham operation, and group 3 rats received an anterior cruciate ligament (ACL) transection. Six rats of each group were randomly assigned to T2 measurement and later subjected to ex vivo analysis of the relative water content of the knee cartilage. The other four rats in each group were killed, and the severity of cartilage degeneration was examined histologically. The knees of the six rats in the ACL transection group were imaged sequentially 4 and 13 weeks after ACL transection, and the relative water content was measured at 13 weeks. RESULTS: The cartilage T2 value was significantly higher 4 and 13 weeks after ACL transection in the operated knees than in the knees of the control and sham groups. The cartilage T2 value was significantly higher at 13 weeks than at 4 weeks in the operated knees. The T2 value was strongly positively correlated with the relative water content (R=0.885, P<0.0001). CONCLUSION: The trend of changes in the T2 values is consistent with an increase in the relative water content in our cartilage degeneration model. This model has potential use for the clinical evaluation of osteoarthritis.


Assuntos
Artrite Experimental/complicações , Doenças das Cartilagens/etiologia , Cartilagem Articular/patologia , Edema/etiologia , Osteoartrite/complicações , Animais , Lesões do Ligamento Cruzado Anterior , Artrite Experimental/etiologia , Água Corporal , Doenças das Cartilagens/diagnóstico , Edema/diagnóstico , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Ratos , Ratos Sprague-Dawley
16.
Sci Adv ; 5(9): eaax3793, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31799401

RESUMO

The precise measurement of the spectrum of protons, the most abundant component of the cosmic radiation, is necessary to understand the source and acceleration of cosmic rays in the Milky Way. This work reports the measurement of the cosmic ray proton fluxes with kinetic energies from 40 GeV to 100 TeV, with 2 1/2 years of data recorded by the DArk Matter Particle Explorer (DAMPE). This is the first time that an experiment directly measures the cosmic ray protons up to ~100 TeV with high statistics. The measured spectrum confirms the spectral hardening at ~300 GeV found by previous experiments and reveals a softening at ~13.6 TeV, with the spectral index changing from ~2.60 to ~2.85. Our result suggests the existence of a new spectral feature of cosmic rays at energies lower than the so-called knee and sheds new light on the origin of Galactic cosmic rays.

17.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 5): m685-6, 2008 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-21202222

RESUMO

In the mol-ecule of the title compound, [Co(C(6)H(4)NO(2))(2)(H(2)O)(2)], the coordination environment around the Co(II) atom is distorted octahedral; two N and two O atoms of the pyridine-2-carboxylate ligands lie in the equatorial plane and the two water O atoms in the axial positions. In the crystal structure, inter-molecular O-H⋯O hydrogen bonds link the mol-ecules, forming a supra-moleular network structure.

18.
Eur J Neurol ; 14(7): 777-82, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17594334

RESUMO

The purpose of this study is to assess the efficacy of hyperbaric oxygen therapy (HBOT) in patients with delayed neuropsychiatric syndrome (DNS) caused by carbon monoxide (CO) inhalation using diffusion tensor magnetic resonance (MR) imaging and neuropsychological test. Conventional and diffusion tensor brain MR imaging exams were performed in six patients with DNS immediately before and 3 months after the HBOT to obtain fractional anisotropy (FA) values. Six age- and sex-matched normal control subjects also received MR exams for comparison. Mini-Mental State Examination (MMSE) was also performed in patients immediately before and 3 months after the HBOT. A significantly higher mean FA value was found in control subjects as compared with the patients both before and 3 months after the HBOT (P < 0.001). The mean FA value 3 months after the HBOT was also significantly higher than that before the HBOT in the patient group (P < 0.001). All of the patients regained full scores in the MMSE 3 months after the HBOT. Diffusion tensor MR imaging can be a quantitative method for the assessment of the white matter change and monitor the treatment response in patients of CO-induced DNS with a good clinical correlation. HBO may be an effective therapy for DNS.


Assuntos
Sintomas Afetivos/terapia , Intoxicação por Monóxido de Carbono/terapia , Transtornos Cognitivos/terapia , Doenças Desmielinizantes/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Oxigenoterapia Hiperbárica , Bainha de Mielina/patologia , Adulto , Sintomas Afetivos/induzido quimicamente , Sintomas Afetivos/patologia , Anisotropia , Intoxicação por Monóxido de Carbono/patologia , Intoxicação por Monóxido de Carbono/psicologia , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/patologia , Doenças Desmielinizantes/induzido quimicamente , Doenças Desmielinizantes/psicologia , Transtorno Depressivo/complicações , Transtorno Depressivo/psicologia , Feminino , Seguimentos , Humanos , Peroxidação de Lipídeos , Masculino , Pessoa de Meia-Idade , Transtornos dos Movimentos/etiologia , Transtornos dos Movimentos/patologia , Transtornos dos Movimentos/terapia , Testes Neuropsicológicos , Tentativa de Suicídio , Fatores de Tempo
19.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 52(11): 684-689, 2017 Nov 09.
Artigo em Zh | MEDLINE | ID: mdl-29972948

RESUMO

Objective: To assess the mandibular condylar growth using cone-beam CT (CBCT) in beagle dogs treated with Herbst appliance and exogenous prostaglandin E2 (PGE2) during late stage of growth. Methods: Twenty-four male beagle dogs aged 8 months were divided into four groups according to the random number table (n=6 in each group): natural growth group, mandibular protraction group (Herbst group), injected prostaglandin E2 group (PGE2 group), mandibular protraction plus injected prostaglandin E2 group (Herbst+PGE2 group). The beagle dogs in Herbst+PGE2 group and PGE2 group were injected 0.1 ml of prostaglandin E2 (dose of 0.05 mg) into bilateral temporomandibular joint articular cavity. The dogs in natural growth group and Herbst group were injected 0.1 ml of saline into bilateral temporomandibular joint articular cavity as control. PGE2 and saline were injected once every 3 days for 60 days, respectively. CBCT was taken before the application of Herbst appliance and after removal of the appliance for all beagle dogs in four groups at the same time. The CBCT images were reconstructed using Invivo5 software and the relevant parameters of temporomandibular joint were measured. Results: No significant difference was found in natural growth group before and after the experiment (P>0.05). After the treatment, the condylar height and condylar size in Herbst group ([0.19+0.04] and [0.18+0.30] mm), PGE2 group ([0.38+0.14] and [0.51+0.24] mm) and Herbst+PGE2 group ([0.65+0.08] and [0.70+0.24] mm) slightly increased (P<0.05). The condylar changes in all experimental groups were greater than the natural growth group (P<0.05), and the ranges of change, in descending order, were Herbst+PGE2 group, PGE2 group and Herbst group (P<0.05). However, the condylar longitudinal distances, condyle width, condylar transverse diameter, glenoid fossa width and glenoid fossa depth had no statistically significant difference among the four groups (P>0.05). Conclusions: Injection of exogenous PGE2 into the temporomandibular joint articular cavity, or using Herbst appliance separately, a certain amount of growth was observed on the mandibular condyle in beagle dogs during late stage of growth. The combination of Herbst appliance and exogenous PGE2 injection made the condylar growth more obviously.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Dinoprostona/farmacologia , Côndilo Mandibular/efeitos dos fármacos , Côndilo Mandibular/diagnóstico por imagem , Animais , Cães , Feminino , Injeções Intra-Articulares , Masculino , Mandíbula , Côndilo Mandibular/crescimento & desenvolvimento , Aparelhos Ortodônticos Funcionais , Distribuição Aleatória , Articulação Temporomandibular
20.
Leukemia ; 19(6): 1058-63, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15815725

RESUMO

Follicular lymphomas (FL) are morphologically classified into grades 1, 2, 3a and 3b by the World Health Organization. Bcl2, Bcl6 and CD10 are phenotypic markers of FL while the Bcl2 t(14;18) and Bcl6 t(3q27) gene translocations are common genetic changes. However, to date, there has been no integrated analysis based on phenotype, grade and genotype from large numbers of FL cases. We graded 261 cases of FL and determined their phenotypes and gene alterations. According to the antigen markers and gene alterations of 147 cases, we classified FL into typical and the others types. The typical group, which includes 69% cases of FL, is characterized by low histological grade (grade 1, 2), coexpression of BCL2 and CD10 and Bcl2 gene translocation. The rest comprises a small part of low-grade FL without Bcl2 gene translocation and high-grade (grade 3a, 3b) FL. These FLs include some heterogeneous disease entities. They are characterized by high histological grade (87%), no definite expression of BCL2 or CD10 and several kinds of gene aberrances including Bcl2 translocation, Bcl6 translocation, Bcl2 amplification or other unknown gene abnormality. Our findings indicate that typical FL presents a homogeneous disease entity whereas the rest comprises heterogeneous diseases entities.


Assuntos
Proteínas de Ligação a DNA/genética , Linfoma Folicular/genética , Linfoma Folicular/patologia , Proteínas Proto-Oncogênicas c-bcl-2/genética , Translocação Genética , Biomarcadores Tumorais , Cromossomos Humanos Par 14 , Cromossomos Humanos Par 18 , Marcadores Genéticos , Genótipo , Humanos , Hibridização in Situ Fluorescente , Linfoma Folicular/classificação , Fenótipo , Proteínas Proto-Oncogênicas c-bcl-6
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