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1.
Magn Reson Med ; 2024 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-39164799

RESUMEN

PURPOSE: Quantitative MRI enables direct quantification of contrast agent concentrations in contrast-enhanced scans. However, the lengthy scan times required by conventional methods are inadequate for tracking contrast agent transport dynamically in mouse brain. We developed a 3D MR fingerprinting (MRF) method for simultaneous T1 and T2 mapping across the whole mouse brain with 4.3-min temporal resolution. METHOD: We designed a 3D MRF sequence with variable acquisition segment lengths and magnetization preparations on a 9.4T preclinical MRI scanner. Model-based reconstruction approaches were employed to improve the accuracy and speed of MRF acquisition. The method's accuracy for T1 and T2 measurements was validated in vitro, while its repeatability of T1 and T2 measurements was evaluated in vivo (n = 3). The utility of the 3D MRF sequence for dynamic tracking of intracisternally infused gadolinium-diethylenetriamine pentaacetic acid (Gd-DTPA) in the whole mouse brain was demonstrated (n = 5). RESULTS: Phantom studies confirmed accurate T1 and T2 measurements by 3D MRF with an undersampling factor of up to 48. Dynamic contrast-enhanced MRF scans achieved a spatial resolution of 192 × 192 × 500 µm3 and a temporal resolution of 4.3 min, allowing for the analysis and comparison of dynamic changes in concentration and transport kinetics of intracisternally infused Gd-DTPA across brain regions. The sequence also enabled highly repeatable, high-resolution T1 and T2 mapping of the whole mouse brain (192 × 192 × 250 µm3) in 30 min. CONCLUSION: We present the first dynamic and multi-parametric approach for quantitatively tracking contrast agent transport in the mouse brain using 3D MRF.

2.
Opt Express ; 32(7): 11774-11793, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38571017

RESUMEN

The imaging spectrometer's high performance in practical applications may be compromised by environmental factors, particularly temperature variations, posing a challenge to its stability. Temperature fluctuations can induce spectral shift, directly impacting the accuracy of spectral measurements, subsequently influencing the precision of radiometric measurements. To address this issue, this study investigates a dual-channel UV imaging spectrometer. This instrument boasts a wavelength calibration accuracy of 0.01 nm. This paper conducts an in-depth analysis of the various mechanisms through which temperature changes influence the spectral line offset in the imaging spectrometer, integrating actual orbital temperature data to discuss the instrument's temperature load settings. The impact of temperature on spectral shift is examined using finite element analysis and optical design software. Estimations of spectral shift were made based on temperature variations. Simulation results indicated that the maximum deviation of spectral shift is estimated at 0.018 nm under a temperature condition of 16 ± 1°C. Under a more controlled orbital temperature condition (16 ± 0.3°C), the maximum deviation of spectral shift decreased to 0.01 nm. Experimental data revealed that at 16 ± 1°C, the maximum deviation of spectral shift did not exceed 0.01 nm. This effectively corroborates our theoretical analysis. The relationship between temperature and spectral shift offers a crucial theoretical foundation for calibrating spectral measurements and managing the thermal conditions of the instrument.

3.
Clin Exp Rheumatol ; 2024 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-39051167

RESUMEN

OBJECTIVES: This study aimed to evaluate the clinical significance of pleural effusion in adult patients with idiopathic inflammatory myopathies (IIM). METHODS: We assessed a cohort of 158 consecutive patients with IIM. Clinical features and survival rates were compared between patients with and without pleural effusion. RESULTS: Of those 158 IIM patients, 28 (17.7%) developed pleural effusion. 125 (79.1%) IIM patients had interstitial lung disease (ILD), 26 (20.8%) of which developed pleural effusion. Notably, pleural effusion was associated with a higher incidence of lower lung zone consolidation, rapidly progressive ILD (RP-ILD) and elevated high-resolution computed tomography (HRCT) score, and could robustly predict RP-ILD independently [HR 7.863 (2.160-28.617), p=0.002] in IIM-ILD patients. IIM patients with pleural effusion presented with increased systemic inflammatory response, including more fever, elevated white blood cell count, neutrophil/lymphocyte ratio, C-reactive protein, and erythrocyte sedimentation rate, alongside reduced lymphocyte percentage. Pleural effusion was also associated with more ILD, lower lung zone consolidation, pericardial effusion and RP-ILD, higher HRCT score, and lower HB and albumin levels in IIM. Except for neutrophil/lymphocyte ratio, ILD and pericardial effusion, other correlative variables were potential predictors of higher mortality in IIM. Furthermore, pleural effusion remained an independent predictor of higher mortality in IIM [HR 5.05 (1.633-15.62), p=0.005]. CONCLUSIONS: Pleural effusion showed a significant positive association with severe phenotypes of ILD and was the powerful predictor of RP-ILD in IIM-ILD. Furthermore, pleural effusion could reveal adverse disease phenotypes with higher systemic inflammatory level and predict higher mortality independently in IIM.

4.
Clin Exp Rheumatol ; 2024 06 06.
Artículo en Inglés | MEDLINE | ID: mdl-38855957

RESUMEN

OBJECTIVES: To investigate the correlation between innate lymphoid cell (ILC) subsets with T-helper (Th) cells and to explore the effect of ILCs on T cells in rheumatoid arthritis (RA). METHODS: We analysed the frequencies of ILC subsets in RA patients with varying disease activity and their correlation with Th cell subsets. We further investigated this correlation in various organs of collagen-induced arthritis (CIA) mice. The effects of ILCs on CD4+ T cells were determined by in vitro cell co-culture experiments. RESULTS: ILCs were less frequent in RA patients than in healthy controls, with higher levels of group 3 ILCs (ILC3s) in RA (p<0.05). ILC3s correlated positively with Th1 and Th17 cells in RA peripheral blood (p<0.05). In the peripheral blood, spleen, and lymph nodes of CIA, ILC3s decreased and then increased during arthritis progression. ILC3s correlated positively with Th1 and Th17 cells in the spleen and lymph nodes of CIA (p<0.05). NKp46+ ILC3s in the spleen positively correlated with Th1 and Th17 cells (p<0.05). Under Th17 cell differentiation conditions, co-culturing CIA-derived ILC3s directly with naive CD4+ T cells promoted Th17 differentiation and increased IL-17 secretion. However, co-culturing through a transwell insert impeded Th17 differentiation without affecting IL-17 secretion. CONCLUSIONS: ILC3s positively correlated with Th1 and Th17 cells in RA. In CIA, the frequencies of ILC3s changed with disease development and showed a positive correlation with Th1 and Th17 cells. ILC3s may facilitate the differentiation of Th17 cells through direct cell-cell contact.

5.
Clin Exp Rheumatol ; 2024 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-38819961

RESUMEN

OBJECTIVES: This study aimed to evaluate the clinical significance of the coexistence of 2 or more myositis-specific antibodies (multiple MSAs) in adult patients with idiopathic inflammatory myopathies (IIM). METHODS: We assessed a cohort of 202 consecutive patients with IIM. Clinical features and survival rates were compared between patients with and without multiple MSAs. RESULTS: Of those 202 patients, 44 (21.8%) were found to have multiple MSAs. 63.6% of the 44 patients tested positive for anti-aminoacyl-tRNA synthetase antibodies (anti-ARS+) and 52.3% positive for anti-melanoma differentiation-associated protein-5 antibody (anti-MDA5+). The presence of multiple MSAs was associated with less rapidly progressive interstitial lung disease (RP-ILD), fever, rash, periungual erythema, more muscle involvement and dysphagia, higher albumin level, and higher positive rate of ANA antibody in anti-MDA5+ population. In anti-ARS+ population with multiple MSAs, there were more V-neck sign, skin ulcers, dysphagia and peripheral edema. No differences in survival rates were observed between patients with or without multiple MSAs in the overall and anti-ARS+ populations. However, the survival rate in anti-MDA5+ population with multiple MSAs was significantly higher than those without multiple MSAs (p = 0.003). Moreover, multiple MSAs remained an independent protective factor against mortality in multivariable Cox regression analysis of anti-MDA5+ population [HR 0.108 (95% CI 0.013, 0.908), p=0.041]. CONCLUSIONS: Multiple MSAs coexist in some IIM patients and their existence indicates mixed features from concomitant MSAs in anti-MDA5+ population and anti-ARS+ population. Identifying multiple MSAs could help to discover a more favourable disease phenotype with decreased mortality in anti-MDA5+ population.

6.
Proc Natl Acad Sci U S A ; 118(13)2021 03 30.
Artículo en Inglés | MEDLINE | ID: mdl-33723013

RESUMEN

With the increasing demand for net-zero sustainable aviation fuels (SAF), new conversion technologies are needed to process waste feedstocks and meet carbon reduction and cost targets. Wet waste is a low-cost, prevalent feedstock with the energy potential to displace over 20% of US jet fuel consumption; however, its complexity and high moisture typically relegates its use to methane production from anaerobic digestion. To overcome this, methanogenesis can be arrested during fermentation to instead produce C2 to C8 volatile fatty acids (VFA) for catalytic upgrading to SAF. Here, we evaluate the catalytic conversion of food waste-derived VFAs to produce n-paraffin SAF for near-term use as a 10 vol% blend for ASTM "Fast Track" qualification and produce a highly branched, isoparaffin VFA-SAF to increase the renewable blend limit. VFA ketonization models assessed the carbon chain length distributions suitable for each VFA-SAF conversion pathway, and food waste-derived VFA ketonization was demonstrated for >100 h of time on stream at approximately theoretical yield. Fuel property blending models and experimental testing determined normal paraffin VFA-SAF meets 10 vol% fuel specifications for "Fast Track." Synergistic blending with isoparaffin VFA-SAF increased the blend limit to 70 vol% by addressing flashpoint and viscosity constraints, with sooting 34% lower than fossil jet. Techno-economic analysis evaluated the major catalytic process cost-drivers, determining the minimum fuel selling price as a function of VFA production costs. Life cycle analysis determined that if food waste is diverted from landfills to avoid methane emissions, VFA-SAF could enable up to 165% reduction in greenhouse gas emissions relative to fossil jet.


Asunto(s)
Biocombustibles , Ácidos Grasos Volátiles/metabolismo , Alimentos , Eliminación de Residuos , Aviación , Catálisis , Gases de Efecto Invernadero , Metano
7.
Sensors (Basel) ; 23(10)2023 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-37430523

RESUMEN

With the development of space telescopes towards high-resolution and intelligent imaging, the scale and complexity of the focal plane components of large-aperture, off-axis, three-mirror anastigmatic (TMA) optical systems are increasing. Traditional focal plane focusing technology reduces the system reliability and increases the scale and complexity. This paper proposes a three-degrees-of-freedom focusing system based on a folding mirror reflector, with a piezoelectric ceramic actuator as the driver. An environment-resistant flexible support was designed for the piezoelectric ceramic actuator through an integrated optimization analysis. The fundamental frequency of the large-aspect-ratio rectangular folding mirror reflector focusing mechanism was around 121.5 Hz. After testing, it was found to meet the requirements of the space mechanics environment. This system shows promise for application to other optical systems as an open-shelf product in the future.

8.
Eur J Nucl Med Mol Imaging ; 49(10): 3492-3507, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35366079

RESUMEN

PURPOSE: Multiple sclerosis (MS) is a disease characterized by inflammatory demyelinated lesions. New treatment strategies are being developed to stimulate myelin repair. Quantitative myelin imaging could facilitate these developments. This first-in-man study aimed to evaluate [11C]MeDAS as a PET tracer for myelin imaging in humans. METHODS: Six healthy controls and 11 MS patients underwent MRI and dynamic [11C]MeDAS PET scanning with arterial sampling. Lesion detection and classification were performed on MRI. [11C]MeDAS time-activity curves of brain regions and MS lesions were fitted with various compartment models for the identification of the best model to describe [11C]MeDAS kinetics. Several simplified methods were compared to the optimal compartment model. RESULTS: Visual analysis of the fits of [11C]MeDAS time-activity curves showed no preference for irreversible (2T3k) or reversible (2T4k) two-tissue compartment model. Both volume of distribution and binding potential estimates showed a high degree of variability. As this was not the case for 2T3k-derived net influx rate (Ki), the 2T3k model was selected as the model of choice. Simplified methods, such as SUV and MLAIR2 correlated well with 2T3k-derived Ki, but SUV showed subject-dependent bias when compared to 2T3k. Both the 2T3k model and the simplified methods were able to differentiate not only between gray and white matter, but also between lesions with different myelin densities. CONCLUSION: [11C]MeDAS PET can be used for quantification of myelin density in MS patients and is able to distinguish differences in myelin density within MS lesions. The 2T3k model is the optimal compartment model and MLAIR2 is the best simplified method for quantification. TRIAL REGISTRATION: NL7262. Registered 18 September 2018.


Asunto(s)
Esclerosis Múltiple , Sustancia Blanca , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Humanos , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/patología , Vaina de Mielina/patología , Tomografía de Emisión de Positrones/métodos , Sustancia Blanca/diagnóstico por imagen , Sustancia Blanca/patología
9.
Clin Exp Rheumatol ; 40(2): 224-236, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34251311

RESUMEN

OBJECTIVES: To identify the risk factors in Chinese patients with adult polymyositis and dermatomyositis for their comorbidities and explore a subclassification system. METHODS: Clinical records of 397 patients with idiopathic inflammatory myopathies were retrospectively reviewed. Logistic regression was used to identify potential risk factors for interstitial lung disease (ILD), other rheumatic diseases, and malignancy after bivariate analysis. Hierarchical clustering and decisional tree were utilised to identify subgroups and explore a subclassification system. RESULTS: A total of 119 polymyositis and 191 dermatomyositis patients were included. Anti-PM/Scl, anti-Ro52, anti-aminoacyl-tRNA synthetase and anti-MDA5 (adjusted odds ratios (AOR)=4.779, 1.917, 5.092 and 7.714 respectively) antibodies were risks (p<0.05), whereas overlapping malignancy was protective (AOR=0.107; p=0.002) for ILD across polymyositis, dermatomyositis and the total group. In subgroup models, Raynaud's phenomenon, arthralgia and semi-quantitative anti-nuclear antibody (AOR=51.233, 4.261, 3.047 respectively) were risks for other overlapping rheumatic diseases (p<0.05). For overlapping malignancy, male and anti-TIF1γ antibodies (AOR=2.533, 16.949) were risks (p<0.05), whereas disease duration and combination of ILD (AOR=0.954, 0.106) were protective in the total group (p<0.05); while anti-NXP2 antibodies were identified as risk factors (AOR=73.152; p=0.038) in polymyositis. Hierarchical clustering suggested a subclassification with 6 subgroups: malignancy overlapping dermatomyositis, classical dermatomyositis, polymyositis with severe muscle involvement, dermatomyositis with ILD, polymyositis with ILD, and overlapping of myositis with other rheumatic diseases. CONCLUSIONS: Accompanying ILD, other rheumatic diseases and malignancy are strongly associated with clinical manifestation and myositis-specific or myositis-associated autoantibodies among Chinese polymyositis and dermatomyositis patients. The subclassification system proposed a more precise phenotype defining toward stratified treatments.


Asunto(s)
Dermatomiositis , Polimiositis , Autoanticuerpos , China/epidemiología , Dermatomiositis/complicaciones , Dermatomiositis/diagnóstico , Dermatomiositis/epidemiología , Humanos , Aprendizaje Automático , Masculino , Estudios Retrospectivos
10.
Sensors (Basel) ; 22(22)2022 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-36433390

RESUMEN

The safety of road construction is one of the most important concerns of construction managers for the following reasons: long-span construction operation, no fixed monitoring cameras, and huge impacts on existing traffic, while the managers still rely on manual inspection and a lack of image records. With the fast development of Unmanned Aerial Vehicle (UAV) and Artificial Intelligence (AI), monitoring safety concerns of road construction sites becomes easily accessible. This research aims to integrate UAVs and AI to establish a UAV-based road construction safety monitoring platform. In this study, road construction safety factors including constructors, construction vehicles, safety signs, and guardrails are defined and monitored to make up for the lack of image data at the road construction site. The main findings of this study include three aspects. First, the flight and photography schemes are proposed based on the UAV platform for information collection for road construction. Second, deep learning algorithms including YOLOv4 and DeepSORT are utilized to automatically detect and track safety factors. Third, a road construction dataset is established with 3594 images. The results show that the UAV-based monitoring platform can help managers with security inspection and recording images.


Asunto(s)
Inteligencia Artificial , Lugar de Trabajo , Algoritmos , Fotograbar
11.
Rheumatology (Oxford) ; 60(5): 2409-2420, 2021 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-33246326

RESUMEN

OBJECTIVES: While myeloid-derived suppressor cells (MDSCs) were previously shown to promote a proinflammatory T helper (Th) 17 response in autoimmune conditions, a potential impact of the MDSC-Th17 immune axis on abnormal bone destruction in RA remains largely unknown. METHODS: We investigated the correlation between the frequency of MDSCs or its subsets and joint destruction in RA patients. The reciprocal actions of patient-derived MDSCs and Th17 cells were studied using osteoclast (OC) differentiation and bone resorption assays in vitro, which were further validated using mouse models of RA. Contribution of MDSCs to osteoclastogenesis and bone erosion in vivo was determined by depletion or transfer of MDSCs. RESULTS: Human MDSCs, particularly monocytic MDSCs (M-MDSCs), exhibit inherent OC-differentiating capacity and positively correlate with clinical bone erosion in RA patients. Strikingly, patient-derived M-MDSCs can program Th17 cells towards a pro-osteoclastogenic phenotype, which in return potentiates OC differentiation via the receptor activator of nuclear factor κΒ ligand (RANK-L)-RANK signalling. This enhanced osteolysis driven by the reciprocal actions of M-MDSCs and Th17 cells is further confirmed using mouse models of RA. Selective depletion of M-MDSCs significantly ameliorates osteoclastogenesis and disease severity in arthritic mice, whereas transfer of M-MDSCs aggravates bone erosion associated with increased OCs in recipient mice. CONCLUSION: Our findings highlight the functional plasticity of MDSCs and identify a novel pro-osteoclastogenic pathway governed by interplay between myeloid cells and T lymphocytes in autoimmune RA.


Asunto(s)
Artritis Reumatoide/inmunología , Resorción Ósea/inmunología , Monocitos/inmunología , Células Supresoras de Origen Mieloide/inmunología , Osteoclastos/inmunología , Células Th17/inmunología , Animales , Artritis Experimental/inmunología , Artritis Experimental/patología , Artritis Reumatoide/patología , Resorción Ósea/patología , Diferenciación Celular/inmunología , Humanos , Ratones , Fenotipo
12.
Mol Cell Biochem ; 459(1-2): 141-150, 2019 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31297660

RESUMEN

Migration and invasion are important characteristics of rheumatoid arthritis fibroblast-like synoviocytes (RA-FLSs), which are involved in joint damage and contribute to rheumatoid arthritis (RA) pathology. However, the underlying mechanisms remain unclear. Because epithelial-mesenchymal transition (EMT) is a key mechanism related to migration and invasion in cancer cells, we investigated the relationship between EMT and RA-FLSs and explored whether the transforming growth factor ß1 (TGF-ß1)/Smad signaling pathway is involved. In vivo, fibroblast-like synoviocytes (FLSs) were isolated from the synovium of RA or osteoarthritis (OA) patients and cultured for 4-8 passages. EMT markers were detected by immunofluorescence and Western blotting. RA-FLSs were treated with TGF-ß1 or Smad2/3 small interfering RNA (siRNA), EMT markers were detected, and migration and invasion were assessed by Transwell assays. EMT markers could be detected in FLSs; when compared with osteoarthritis fibroblast-like synoviocytes (OA-FLSs), E-cadherin and vimentin decreased, while N-cadherin and α-smooth muscle actin (α-SMA) increased in RA-FLSs. Furthermore, TGF-ß1 enhanced migration and invasion by inducing EMT via activating Smad2/3 in RA-FLSs. Phosphorylation of Smad2/3 was accompanied by degradation of Smad3. Silencing Smad2/3 blocked EMT and inhibited the migration and invasion induced by TGF-ß1. Matrix metalloproteinase 9 (MMP9) and vimentin were not affected when cells were treated with TGF-ß1 or Smad2/3 siRNA. The TGF-ß1/Smad signaling pathway is involved in EMT and contributes to migration and invasion in RA-FLSs. Interestingly, vimentin decreased in RA-FLSs, but there is no correlation between vimentin and TGF-ß1/Smad signaling pathway. Thus, further research on vimentin should be conducted.


Asunto(s)
Artritis Reumatoide/metabolismo , Movimiento Celular , Fibroblastos/metabolismo , Transducción de Señal , Proteína Smad2/metabolismo , Proteína smad3/metabolismo , Sinoviocitos/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , Artritis Reumatoide/patología , Células Cultivadas , Femenino , Fibroblastos/patología , Humanos , Masculino , Metaloproteinasa 9 de la Matriz/metabolismo , Sinoviocitos/patología
13.
Angew Chem Int Ed Engl ; 58(39): 13727-13733, 2019 Sep 23.
Artículo en Inglés | MEDLINE | ID: mdl-31298771

RESUMEN

2D graphitic carbon nitride (g-C3 N4 ) nanosheets are a promising negative electrode candidate for sodium-ion batteries (NIBs) owing to its easy scalability, low cost, chemical stability, and potentially high rate capability. However, intrinsic g-C3 N4 exhibits poor electronic conductivity, low reversible Na-storage capacity, and insufficient cyclability. DFT calculations suggest that this could be due to a large Na+ ion diffusion barrier in the innate g-C3 N4 nanosheet. A facile one-pot heating of a mixture of low-cost urea and asphalt is strategically applied to yield stacked multilayer C/g-C3 N4 composites with improved Na-storage capacity (about 2 times higher than that of g-C3 N4 , up to 254 mAh g-1 ), rate capability, and cyclability. A C/g-C3 N4 sodium-ion full cell (in which sodium rhodizonate dibasic is used as the positive electrode) demonstrates high Coulombic efficiency (ca. 99.8 %) and a negligible capacity fading over 14 000 cycles at 1 A g-1 .

14.
Magn Reson Med ; 79(1): 256-263, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28295552

RESUMEN

PURPOSE: The current study aimed to develop a three-dimensional (3D) dynamic oxygen-17 (17 O) MR imaging method with high temporal and spatial resolution to delineate the kinetics of 17 O water uptake and washout in the brains of mice with glioblastoma (GBM). METHODS: A 3D imaging method with a stack-of-stars golden-ratio-based radial sampling scheme was employed to acquire 17 O signal in vivo. A k-space-weighted image reconstruction method was used to improve the temporal resolution while preserving spatial resolution. Simulation studies were performed to validate the method. Using this method, the kinetics of 17 O water uptake and washout in the brains of mice with GBM were delineated after an intravenous bolus injection of 17 O water. RESULTS: The proposed 17 O imaging method achieved an effective temporal resolution of 7.56 s with a nominal voxel size of 5.625 µL in the mouse brain at 9.4 T. Reduced uptake and prolonged washout of 17 O water were observed in tumor tissue, suggesting compromised cerebral perfusion. CONCLUSION: This study demonstrated a promising dynamic 17 O imaging approach that can delineate 17 O water kinetics in vivo with high temporal and spatial resolution. It can also be used to image cerebral oxygen consumption rate in oxygen-17 inhalation studies. Magn Reson Med 79:256-263, 2018. © 2017 International Society for Magnetic Resonance in Medicine.


Asunto(s)
Neoplasias Encefálicas/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Glioblastoma/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Isótopos de Oxígeno/química , Agua/química , Algoritmos , Animales , Simulación por Computador , Medios de Contraste , Aumento de la Imagen , Interpretación de Imagen Asistida por Computador , Imagenología Tridimensional , Cinética , Imagen por Resonancia Magnética , Masculino , Ratones , Ratones Desnudos , Fantasmas de Imagen
15.
Clin Exp Rheumatol ; 35(3): 452-461, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28032844

RESUMEN

OBJECTIVES: Zaocys type II collagen is an active collagen extracted from Zaocys that has been used to treat rheumatoid arthritis in China for over 1000 years. However, the mechanism still remains unknown. Therefore, we set out to investigate the inhibitory effect and possible mechanism of action of zaocys type II collagen on collagen-induced arthritis. METHODS: Collagen-induced arthritis was induced in C57BL/6 mice by immunisation with type II collagen. After immunisation, the mice were treated with Zaocys type II collagen. Clinical and histological scores were assessed and the cytokine levels in the serum and lymphocytes supernatant from the spleen and mesenteric lymph node were determined by enzyme-linked immune sorbent assay. The T-helper 17 cell and regulatory-T cell frequencies were analysed by flow cytometry and the expression of interest markers was examined by direct immuno-fluorescence. RESULTS: The arthritis score and severity of histological inflammation and cartilage destruction were dose-dependently reduced after treatment. The analysis results indicated that Zaocys type II collagen significantly increased the proportion of regulatory-T cells and lowered the T-helper 17 cells, it also increased the number of regulatory-T cells and conversely decreased the T-helper 17 cells in synovial tissue compared with the model group. Treatment also caused a higher level of transforming growth factor-ß and a decreased production of interleukin -17A. CONCLUSIONS: The oral administration of Zaocys type II collagen potently suppressed the severity of collagen-induced arthritis by repairing the imbalance between regulatory-T cells and T-helper 17 cells, suggesting that it might be a promising candidate for the treatment of rheumatoid arthritis.


Asunto(s)
Antirreumáticos/farmacología , Artritis Experimental/prevención & control , Colágeno Tipo II/farmacología , Membrana Sinovial/efectos de los fármacos , Linfocitos T Reguladores/efectos de los fármacos , Células Th17/efectos de los fármacos , Administración Oral , Animales , Antirreumáticos/administración & dosificación , Artritis Experimental/sangre , Artritis Experimental/inducido químicamente , Artritis Experimental/inmunología , Colágeno Tipo II/administración & dosificación , Citocinas/sangre , Relación Dosis-Respuesta a Droga , Adyuvante de Freund , Mediadores de Inflamación/sangre , Ganglios Linfáticos/efectos de los fármacos , Ganglios Linfáticos/inmunología , Ganglios Linfáticos/metabolismo , Masculino , Ratones Endogámicos C57BL , Índice de Severidad de la Enfermedad , Bazo/efectos de los fármacos , Bazo/inmunología , Bazo/metabolismo , Membrana Sinovial/inmunología , Membrana Sinovial/metabolismo , Linfocitos T Reguladores/inmunología , Linfocitos T Reguladores/metabolismo , Células Th17/inmunología , Células Th17/metabolismo , Factores de Tiempo
16.
Chin J Cancer Res ; 28(3): 286-300, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-27478314

RESUMEN

OBJECTIVE: This study estimates the numbers of new cancer cases and cancer deaths in Hebei province using incidence and mortality data from 9 population-based cancer registries in 2012. METHODS: The data of new diagnosed cancer cases and cancer deaths in 2012 were collected from 9 population-based cancer registries of Hebei province in 2015. All the data met the National Central Cancer Registry of China (NCCR) criteria of data quality. The pooled data analysis was stratified by areas (urban/rural), gender, age group (0, 1.4, 5.9, 10.14, …, 85+) and cancer type. New cancer cases and deaths in Hebei province were estimated using age-specific rates and corresponding provincial population in 2012. The 10 most common cancers in different groups and the cumulative rates were calculated. Chinese population census in 2000 and Segi's population were used for age-standardized incidence/mortality rates. RESULTS: All cancer registries covered 4,986,847 populations, 6.84% of Hebei provincial population (2,098,547 in urban and 2,888,300 in rural areas). The percentage of cases morphologically verified (MV%) and death certificate-only cases (DCO%) were 76.40% and 4.72%, respectively. The mortality to incidence rate ratio (M/I) was 0.64. In 2012, it is estimated that there were about 187,900 new diagnosed cancer cases and 119,800 cancer deaths in Hebei province. The incidence rate of cancer was 258.12/100,000 (275.75/100,000 in males, 239.78/100,000 in females), and the age-standardized incidence rates by Chinese standard population (ASIRC) and by world standard population (ASIRW) were 210.65/100,000 and 208.50/100,000, with the cumulative incidence rates (0.74 years old) of 24.46%. The cancer incidence and ASIRC were 256.99/100,000 and 211.32/100,000 in urban areas and 258.94/100,000 and 209.99/100,000 in rural areas, respectively. The cancer mortality rate was 164.63/100,000 (201.85/100,000 in males, 125.92/100,000 in females). Agestandardized mortality rates by Chinese standard population (ASMRC) and by world standard population (ASMRW) were 137.30/100,000 and 137.39/100,000 with the cumulative mortality rate (0.74 years old) of 14.58%, respectively. The cancer mortality rate in rural areas (167.16/100,000) was higher than that in urban areas (161.16/100,000). The most common cancers were lung cancer, stomach cancer, breast cancer, esophageal cancer, liver cancer and colorectal cancer, which accounted for 72.31% of all cancer cases. Lung cancer, stomach cancer, liver cancer, esophageal cancer and colorectal cancer were the major causes of cancer death in Hebei province, which accounted for 75.24% of all cancer deaths. The cancer spectrum differs between urban and rural, males and females in both incidence and mortality rates. CONCLUSIONS: The most common cancers were lung cancer, stomach cancer, esophageal cancer, breast cancer, liver cancer and colorectal cancer in Hebei province.

17.
Ann Neurol ; 74(5): 688-98, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23818306

RESUMEN

OBJECTIVE: Novel therapeutic interventions aimed at myelin repair are now under development for neuroprotection as well as functional recovery of patients with multiple sclerosis. However, development of myelin repair therapy necessitates a noninvasive approach for measuring changes in myelin content in vivo in a quantitative fashion not yet possible using magnetic resonance imaging. For this reason, we developed a novel positron emission tomography (PET) probe, termed [11C]MeDAS, that is capable of longitudinally imaging central nervous system myelin content. METHODS: The binding properties of [11C]MeDAS for myelin were systematically evaluated by in vitro and in situ fluorescent staining of the spinal cord and the brain, and by in vivo competitive blocking studies. Longitudinal PET studies were conducted in 3 rat models involving acute focal neuroinflammation in the brain, lysophosphatidylcholine (LPC)-induced focal demyelination in the spinal cord, and experimental autoimmune encephalomyelitis (EAE). Image-guided myelin repair therapy was conducted in an LPC rat model using a mesenchymal stem cell-based hepatocyte growth factor (HGF). Biodistribution and acute toxicity studies of [11C]MeDAS were also conducted. RESULTS: MeDAS selectively stains myelin in the spinal cord and brain. Neuroinflammation did not affect [11C]MeDAS uptake in the brain as long as the myelin sheaths remained intact. Longitudinal PET studies in LPC and EAE rat models demonstrate that [11C]MeDAS uptake changes correlate with associated myelin loss in the spinal cord. Furthermore, using [11C]MeDAS-PET, the efficacy of myelin repair therapy with HGF was longitudinally monitored in vivo. INTERPRETATION: [11C]MeDAS-PET is a promising imaging marker for monitoring myelin pathology in vivo, future applications of which in humans should be achievable.


Asunto(s)
Enfermedades Desmielinizantes/diagnóstico por imagen , Encefalomielitis Autoinmune Experimental/diagnóstico por imagen , Vaina de Mielina/diagnóstico por imagen , Médula Espinal/diagnóstico por imagen , Animales , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Enfermedades Desmielinizantes/inducido químicamente , Enfermedades Desmielinizantes/patología , Encefalomielitis Autoinmune Experimental/patología , Femenino , Vaina de Mielina/patología , Tomografía de Emisión de Positrones/métodos , Ratas , Ratas Sprague-Dawley , Médula Espinal/patología
18.
Zhong Yao Cai ; 37(6): 1020-4, 2014 Jun.
Artículo en Zh | MEDLINE | ID: mdl-25470970

RESUMEN

OBJECTIVE: To analyze the homology of Zaocys type 1I collagen ( ZC II ) with the C II collagen from other species, and to investigate the effect of ZC II on arthritis in mice with collagen-induced arthritis (CIA). METHODS: ZC II was purified with restriction pepsin digestion. Then SDS-PAGE gel electrophoresis and UV spectrophotometry were used to identify the protein,the homology of the ZC II peptide was analyzed with Mass Spectrometry. The model of CIA mice were induced by subcutaneous injection of Chicken C II into male C57BL/6 mice from the base of the tails. After immunization,ZC II [H,M,L:40,20 and 10 µg/(kgd) ]was administered orally to mice from day 21 to 28 accordingly. The severity of the arthritis in each limb was evaluated using a macroscopic scoring system, and his- topathological change of joint was observed by light microscope with HE staining. RESULTS: The molecular weight of ZC II protein deter- mined by SDS-PAGE gel electrophoresis was between 110 kD and 140 kD, and UV absorption peak appeared at around 230 nm in wave- length. The peptide mass fingerprinting(PMF) of the purified protein by Mass Spectrometry analysis showed that it had at least 4 peptides matched with other species,and the protein score was greater than 95%. Compared with normal group,the CIA model group had significantly higher scores for arthritis and histopathological changes (P <0. 05). Meanwhile,the same scores for the ZC II peptide-treated mice with CIA were significantly lower than the mice from CIA model group(P <0. 05). CONCLUSION: Results of Mass Spectrometry analysis demonstrate that ZC II has high homology with the C II from other species. Oral administration of ZC II can suppress arthritis in mice with CIA and ameliorate the histopathological changes of the joint.


Asunto(s)
Artritis Experimental/tratamiento farmacológico , Colágeno Tipo II/uso terapéutico , Animales , Artritis , Artritis Experimental/inducido químicamente , Electroforesis en Gel de Poliacrilamida , Articulaciones , Masculino , Ratones , Ratones Endogámicos C57BL
19.
Inflammation ; 47(1): 129-144, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37688661

RESUMEN

Dickkopf-1 (DKK-1) has been considered a master regulator of bone remodeling. As precursors of osteoclasts (OCs), myeloid-derived suppressor cells (MDSCs) were previously shown to participate in the process of bone destruction in rheumatoid arthritis (RA). However, the role of DKK-1 and MDSCs in RA is not yet fully understood. We investigated the relevance between the level of DKK-1 and the expression of MDSCs in different tissues and joint destruction in RA patients and collagen-induced arthritis (CIA) mouse models. Furthermore, the CIA mice were administered recombinant DKK-1 protein. The arthritis scores, bone destruction, and the percentage of MDSCs in the peripheral blood and spleen were monitored. In vitro, the differentiation of MDSCs into OCs was intervened with recombinant protein and inhibitor of DKK-1. The number of OCs differentiated and the protein expression of the Wnt/ß-catenin signaling pathway were explored. The level of DKK-1 positively correlates with the frequency of MDSCs and bone erosion in RA patients and CIA mice. Strikingly, recombinant DKK-1 intervention significantly exacerbated arthritis scores and bone destruction, increasing the percentage of MDSCs in the peripheral blood and spleen in CIA mice. In vitro experiments showed that recombinant DKK-1 promoted the differentiation of MDSCs into OCs, reducing the expression of ß-catenin and TCF4 and increasing the expression of CyclinD1. In contrast, the DKK-1 inhibitor had the opposite effect. Our findings highlight that DKK-1 promoted MDSCs expansion in RA and enhanced the differentiation of MDSCs into OCs via targeting the Wnt/ß-catenin pathway, aggravating the bone destruction in RA.


Asunto(s)
Artritis Experimental , Artritis Reumatoide , Osteólisis , Animales , Humanos , Ratones , Artritis Experimental/inducido químicamente , Artritis Experimental/metabolismo , Artritis Reumatoide/metabolismo , beta Catenina/metabolismo , Osteoclastos/metabolismo
20.
ArXiv ; 2024 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-38745701

RESUMEN

Purpose: Quantitative MRI enables direct quantification of contrast agent concentrations in contrast-enhanced scans. However, the lengthy scan times required by conventional methods are inadequate for tracking contrast agent transport dynamically in mouse brain. We developed a 3D MR fingerprinting (MRF) method for simultaneous T1 and T2 mapping across the whole mouse brain with 4.3-min temporal resolution. Method: We designed a 3D MRF sequence with variable acquisition segment lengths and magnetization preparations on a 9.4T preclinical MRI scanner. Model-based reconstruction approaches were employed to improve the accuracy and speed of MRF acquisition. The method's accuracy for T1 and T2 measurements was validated in vitro, while its repeatability of T1 and T2 measurements was evaluated in vivo (n=3). The utility of the 3D MRF sequence for dynamic tracking of intracisternally infused Gd-DTPA in the whole mouse brain was demonstrated (n=5). Results: Phantom studies confirmed accurate T1 and T2 measurements by 3D MRF with an undersampling factor up to 48. Dynamic contrast-enhanced (DCE) MRF scans achieved a spatial resolution of 192 ✕ 192 ✕ 500 µm3 and a temporal resolution of 4.3 min, allowing for the analysis and comparison of dynamic changes in concentration and transport kinetics of intracisternally infused Gd-DTPA across brain regions. The sequence also enabled highly repeatable, high-resolution T1 and T2 mapping of the whole mouse brain (192 ✕ 192 ✕ 250 µm3) in 30 min. Conclusion: We present the first dynamic and multi-parametric approach for quantitatively tracking contrast agent transport in the mouse brain using 3D MRF.

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