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1.
Chin Med Sci J ; 38(1): 66-69, 2023 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-36727414

RESUMEN

Both anti-glomerular basement membrane (GBM) disease and the anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) are common causes of pulmonary-renal syndrome. Organizing pneumonia (OP), a special pattern of interstitial lung disease, is extremely rare either in AAV or anti-GBM disease. We report an old woman presented with OP on a background of co-presentation with both ANCA and anti-GBM antibodies.


Asunto(s)
Enfermedad por Anticuerpos Antimembrana Basal Glomerular , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos , Glomerulonefritis , Neumonía Organizada , Neumonía , Femenino , Humanos , Anticuerpos Anticitoplasma de Neutrófilos , Autoanticuerpos , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/complicaciones
2.
Comput Methods Biomech Biomed Engin ; 26(6): 744-753, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-35695468

RESUMEN

Low-profile angle-stable spacer Zero-P is claimed to reduce the morbidity associated with traditional plate and cage construct (PCC). Both Zero-P and PCC could achieve comparable mid- and long-term clinical and radiological outcomes in anterior cervical discectomy and fusion (ACDF). It is not clear whether Zero-P can reduce the incidence of adjacent segment degeneration (ASD), especially in multi-segmental fusion. This study aimed to test the effect of fusion level with Zero-P versus with PCC on adjacent-segment biomechanics in ACDF. A three-dimensional finite element (FE) model of an intact C2-T1 segment was built and validated. Six single- or double-level instrumented conditions were modeled from this intact FE model using Zero-P or the standard PCC. The biomechanical responses of adjacent segments at the cephalad and caudal levels of the operation level were assessed in terms of range of motion (ROM), stresses in the endplate and disc, loads in the facets. When comparing the increase of adjacent-segment motion in single-level PCC fusion versus Zero-P fusion, a significantly larger increase was found in double-level fusion condition. The fold changes of PCC versus Zero-P of intradiscal and endplate stress, and facet load at adjacent levels in the double-level fusion spine were significantly larger than that in the single-level fusion spine during the sagittal, the transverse, and the frontal plane motion. The increased value of biomechanical features was greater at above segment than that at below. The fold changes of PCC versus Zero-P at adjacent segment were most notable in flexion and extension movement. Low-profile device could decrease adjacent segment biomechanical burden compared to traditional PCC in ACDF, especially in double-level surgery. Zero-P could be a good alternative for traditional PCC in ACDF. Further clinical/in vivo studies will be necessary to explore the approaches selected for this study is warranted.


Asunto(s)
Vértebras Cervicales , Fusión Vertebral , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Vértebras Cervicales/fisiología , Fenómenos Biomecánicos/fisiología , Placas Óseas , Discectomía/métodos , Fusión Vertebral/métodos , Rango del Movimiento Articular/fisiología
3.
Huan Jing Ke Xue ; 43(11): 4992-4999, 2022 Nov 08.
Artículo en Chino | MEDLINE | ID: mdl-36437071

RESUMEN

As a type of emerging pollutant of concern, organophosphate esters (OPEs) have posed a moderate risk to the remote Antarctic waters. Triphenyl phosphate (TPHP) is a common type of OPEs in water, which has been proven to have toxic effects, bioaccumulation, and amplification effects and pose a great threat to the environment and human health. Fourier transform infrared spectroscopy (FT-IR) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to investigate the degradation process of TPHP in three advanced oxidation processes (UV-AOPs), including ultraviolet-hydrogen peroxide (UV-H2O2), ultraviolet-titanium dioxide (UV-TiO2), and ultraviolet-persulfate (UV-PS) systems. This was the first instance of using FT-IR for the online observation of the change in infrared characteristic peaks in the degradation process of TPHP, and its degradation reaction kinetics, photodegradation products, and degradation pathways were analyzed. The results showed that TPHP could be effectively degraded under UV-H2O2, UV-TiO2, and UV-PS systems, and the photodegradation half-lives were 74, 150, and 89 min, respectively. The UV-H2O2 system had the best degradation effect on TPHP. Additionally, the degradation reactions of TPHP in three systems conformed to the first-order kinetics. When the concentration of H2O2 was 0-0.097 mol·L-1, the increase in H2O2 concentration promoted the degradation of TPHP, and when the concentration of TiO2 was 0-0.013 mol·L-1, the increase in TiO2 concentration promoted the degradation of TPHP. The photodegradation pathway of TPHP mainly included the P-O-C bond breaking, the C-H bond cleavage of the benzene ring structure and the hydrolysis reaction of TPHP. The UV-H2O2 system was used to degrade OPEs in the environmental water of Chengdu, and it was found that the removal rate of TPHP was 66% when the water samples of the park landscape water were degraded for 60 min.


Asunto(s)
Peróxido de Hidrógeno , Agua , Humanos , Peróxido de Hidrógeno/química , Cromatografía Liquida , Espectroscopía Infrarroja por Transformada de Fourier , Rayos Ultravioleta , Espectrometría de Masas en Tándem , Organofosfatos
4.
Huan Jing Ke Xue ; 43(6): 3253-3261, 2022 Jun 08.
Artículo en Chino | MEDLINE | ID: mdl-35686795

RESUMEN

Surface soil samples collected at 18 sites from the northeast Tibetan Plateau were used to analyze perfluoroalkyl substances (PFASs) via ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) to study the concentration levels and sources of PFASs. The results showed that 11 PFASs were detected in the soil, and the ω(Σ11PFASs) ranged from 0.043-1.573 ng·g-1 with an average concentration of 0.398 ng·g-1. PFBA displayed the highest concentration level with a mean content of 0.164 ng·g-1, whereas PFHxA was at the lowest level (0.005 ng·g-1). The concentrations of the other PFASs were similar to each other (0.011-0.057 ng·g-1). Generally, PFASs contents in the west and north were higher than that in the southeast, and the alpine condensation effect existed for PFBA. The principal component analysis showed that PFASs in surface soils in the northeast Tibetan Plateau region mainly originated from the atmospheric transport of PFASs and their precursors. Few areas were affected by direct emissions of point source pollution, and the main sources were the industrial production of metals/minerals and other human activities.


Asunto(s)
Ácidos Alcanesulfónicos , Fluorocarburos , Contaminantes Químicos del Agua , Ácidos Alcanesulfónicos/análisis , Cromatografía Liquida , Monitoreo del Ambiente , Fluorocarburos/análisis , Humanos , Suelo/química , Espectrometría de Masas en Tándem , Tibet , Contaminantes Químicos del Agua/análisis
5.
Chin Med Sci J ; 37(4): 359-362, 2022 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-35762176

RESUMEN

Renal amyloidosis secondary to anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is extremely rare. Here, we reported a 77-year-old woman with ANCA-associated vasculitis. Renal biopsy with Masson trichrome staining showed pauci-immune crescentic glomerulonephritis, and electron microscopy showed amyloid deposition in the mesangial area. Immunofluorescence revealed kappa light chain and lambda light chain negative. Bone marrow biopsy revealed no clonal plasma cell. Finally, she was diagnosed as ANCA-associated vasculitis with secondary renal amyloid A amyloidosis.


Asunto(s)
Amiloidosis , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos , Glomerulonefritis , Femenino , Humanos , Anciano , Glomerulonefritis/etiología , Glomerulonefritis/diagnóstico , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/complicaciones , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/patología , Anticuerpos Anticitoplasma de Neutrófilos , Riñón/patología , Amiloidosis/complicaciones
6.
Front Endocrinol (Lausanne) ; 13: 833413, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35388295

RESUMEN

Objectives: To assess the accuracy of computed tomography (CT)-based machine learning models for differentiating subclinical pheochromocytoma (sPHEO) from lipid-poor adenoma (LPA) in patients with adrenal incidentalomas. Patients and Methods: The study included 188 tumors in the 183 patients with LPA and 92 tumors in 86 patients with sPHEO. Pre-enhanced CT imaging features of the tumors were evaluated. Machine learning prediction models and scoring systems for differentiating sPHEO from LPA were built using logistic regression (LR), support vector machine (SVM) and random forest (RF) approaches. Results: The LR model performed better than other models. The LR model (M1) including three CT features: CTpre value, shape, and necrosis/cystic changes had an area under the receiver operating characteristic curve (AUC) of 0.917 and an accuracy of 0.864. The LR model (M2) including three CT features: CTpre value, shape and homogeneity had an AUC of 0.888 and an accuracy of 0.832. The S2 scoring system (sensitivity: 0.859, specificity: 0.824) had comparable diagnostic value to S1 (sensitivity: 0.815; specificity: 0.910). Conclusions: Our results indicated the potential of using a non-invasive imaging method such as CT-based machine learning models and scoring systems for predicting histology of adrenal incidentalomas. This approach may assist the diagnosis and personalized care of patients with adrenal tumors.


Asunto(s)
Adenoma , Neoplasias de las Glándulas Suprarrenales , Feocromocitoma , Adenoma/diagnóstico por imagen , Adenoma/patología , Neoplasias de las Glándulas Suprarrenales/diagnóstico por imagen , Humanos , Lípidos , Aprendizaje Automático , Feocromocitoma/diagnóstico por imagen , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos
7.
BMC Infect Dis ; 22(1): 125, 2022 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-35123391

RESUMEN

BACKGROUND: Schistosomiasis is one of the most contagious parasitic diseases affecting humans; however, glomerular injury is a rare complication mainly described with Schistosoma mansoni infection. We report a case of membranous nephropathy associated with Schistosoma japonicum infection in a Chinese man. CASE PRESENTATION: A 51-year-old Chinese male with a long history of S. japonicum infection presented to the hospital with a slowly progressing severe lower limb edema and foaming urine for over 5 months. Serum S. japonicumantigen test was positive and immunohistochemistry showed that the glomeruli were positive for the antigens. The renal pathologic diagnosis was stage III membranous nephropathy. The patient was treated with glucocorticoid, praziquantel, and an angiotensin-converting enzyme inhibitor. The edema in both lower limbs disappeared within 2 weeks, but his renal function declined progressively and proteinuria persisted after 5 months of therapy. CONCLUSIONS: Different classes of schistosomal glomerulopathy have completely different clinical manifestation and prognosis. Therefore, efforts should focus on alleviating symptoms, prevention, and early detection. S. japonicumassociated with membranous nephropathy may show a good curative effect and prognosis. However, it is necessary to monitor the renal function in such patients.


Asunto(s)
Glomerulonefritis Membranosa , Schistosoma japonicum , Esquistosomiasis Japónica , Esquistosomiasis mansoni , Esquistosomiasis , Animales , Glomerulonefritis Membranosa/complicaciones , Glomerulonefritis Membranosa/diagnóstico , Glomerulonefritis Membranosa/tratamiento farmacológico , Humanos , Riñón , Masculino , Persona de Mediana Edad , Esquistosomiasis Japónica/complicaciones , Esquistosomiasis Japónica/diagnóstico , Esquistosomiasis Japónica/tratamiento farmacológico
8.
Eur J Nucl Med Mol Imaging ; 49(8): 2821-2832, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-34860277

RESUMEN

PURPOSE: Growing evidence proved the efficacy of multi-parametric MRI (mpMRI) and prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT)-guided targeted biopsy (TB) in prostate cancer (PCa) diagnosis, but there is no direct comparison between mpMRI-TB and PSMA PET/CT-TB. Gastrin-releasing peptide receptor (GRPR) is highly expressed in PCa, which can compensate for the unstable expression of PSMA in PCa. Therefore, we designed a study to compare the efficiency of mpMRI-TB, dual-tracer (GRPR and PSMA) PET/CT-TB, systematic biopsy, and combined biopsy for the diagnosis of prostate cancer. METHODS: One hundred twelve suspicious PCa patients were enrolled from September 2020 to June 2021. Patients with anyone of positive dual-tracer PET/CT or mpMRI underwent TB, and all enrolled patients underwent systematic biopsy (SB) after TB. The primary outcome was the detection rates of PCa in different biopsy strategies. Secondary outcomes were the performance of three imaging methods, omission diagnostic rates, and upgrading and downgrading of biopsy samples relative to those of prostatectomy specimens in different biopsy strategies. McNemar's tests and Bonferroni correction in multiple comparisons were used to compare the primary and secondary outcomes. RESULTS: In 112 men, clinically significant PCa (grade group[GG] ≥ 2) accounted for 34.82% (39/112), and nonclinically significant PCa (GG = 1) accounted for 4.46% (5/112). 68 Ga-PSMA PET/CT-TB achieved higher PCa detection rate (69.77%) and positive ratio of biopsy cores (0.44) compared with SB (39.29% and 0.12) and mpMRI-TB (36.14% and 0.23), respectively (P < 0.005). Dual-tracer PET/CT screen out patients for avoiding 52.67% (59/112) unnecessary biopsy, whereas dual-tracer PET/CT-TB plus SB achieved high detection rate (77.36%) without misdiagnosis of csPCa. CONCLUSION: Dual-tracer PET/CT might screen patients for avoiding unnecessary biopsy. Dual-tracer PET/CT-TB plus SB might be a more effective and promising strategy for the definite diagnosis of clinically significant PCa than mpMRI-TB.


Asunto(s)
Imágenes de Resonancia Magnética Multiparamétrica , Neoplasias de la Próstata , Biopsia , Radioisótopos de Galio , Humanos , Biopsia Guiada por Imagen , Masculino , Proyectos Piloto , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Neoplasias de la Próstata/patología , Receptores de Bombesina
9.
Artículo en Inglés | WPRIM (Pacífico Occidental) | ID: wpr-970691

RESUMEN

Renal amyloidosis secondary to anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is extremely rare. Here, we reported a 77-year-old woman with ANCA-associated vasculitis. Renal biopsy with Masson trichrome staining showed pauci-immune crescentic glomerulonephritis, and electron microscopy showed amyloid deposition in the mesangial area. Immunofluorescence revealed kappa light chain and lambda light chain negative. Bone marrow biopsy revealed no clonal plasma cell. Finally, she was diagnosed as ANCA-associated vasculitis with secondary renal amyloid A amyloidosis.


Asunto(s)
Femenino , Humanos , Anciano , Glomerulonefritis/diagnóstico , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/patología , Anticuerpos Anticitoplasma de Neutrófilos , Riñón/patología , Amiloidosis/complicaciones
10.
Comput Methods Programs Biomed ; 209: 106355, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34418812

RESUMEN

BACKGROUND AND OBJECTIVE: Mechanics and biology may be interconnected and amplify each other during disc degeneration. It remains unknown the influence of pre-existing disc degeneration and its impact on adjacent segment degeneration (ASD) after anterior cervical discectomy and fusion (ACDF). This study aimed to discuss the necessity of including degenerated adjacent segments in single-level ACDF surgery from a biomechanical view. METHODS: A poroelastic C2-T1 finite element model was created and validated. A C5-C6 ACDF model was developed based on this normal model. Moderate C4-C5 disc degeneration was created by appropriately modifying the morphology and tissue material properties in this fusion model. Degenerative morphology was modeled based on Thompson's grading system and Walraevens's scoring system for cervical spine, including disc height, whole disc area, nucleus pulposus (NP) area, endplate sclerosis and curvature. Stresses in disc and endplate and loads in facet joint were computed under moment loads in the fusion models with normal and pre-existing degenerative disc condition. RESULTS: As for the adjacent disc, the stress values in degenerative condition were 7.41%, 5% and 5.26% larger than that in normal situation during extension, axial rotation and lateral bending motion, respectively. The disc stress changes mainly stemmed from annulus fibrosus (AF) tissue, but not NP. In the endplate, stress values of degeneration status were 4.17, 4.35 and 6.06% larger than that of normal condition under axial rotation, lateral bending and extension. The facet load magnitudes of pre-existing degeneration were 11.28, 11.57, 11.78 and 11.42% greater than that of normal condition in flexion, extension, axial rotation and lateral bending motion. CONCLUSION: Pre-existing degenerated disc experience increased biomechanical changes in adjacent segment after single-level ACDF. It may pose a long-term cumulative problem related to biomechanics in cervical spine after fusion. Before surgery, surgeons should be careful about selecting the fusion level.


Asunto(s)
Degeneración del Disco Intervertebral , Disco Intervertebral , Fusión Vertebral , Fenómenos Biomecánicos , Vértebras Cervicales/cirugía , Análisis de Elementos Finitos , Humanos , Rango del Movimiento Articular
11.
Huan Jing Ke Xue ; 42(7): 3549-3554, 2021 Jul 08.
Artículo en Chino | MEDLINE | ID: mdl-34212681

RESUMEN

In this study, soil samples were collected from the eastern edge of the Qinghai Tibet Plateau in December 2019. The level and distribution characteristics of organophosphate esters (OPEs) in seasonal frozen soil were analyzed, and their sources were discussed. The results showed that the target analytes including tri-n-butyl phosphate (TnBP), tris(2-ethylhexyl) phosphate (TEHP), tributoxyethyl phosphate (TBEP), triphenyl phosphate (TPhP), tri(2-chloroethyl) phosphate (TCEP), trichloropropyl phosphate (TCPP), and tris-(2,3-dichloropropyl) phosphate (TDCPP) were detected with 100% frequency. Levels of Σ7OPEs in topsoil (0-10 cm) and sub topsoil (10-20 cm) were 146.7-348.7 ng·g-1 (mean:231.1 ng·g-1) and 206.5-333.2 ng·g-1 (mean:260.2 ng·g-1), respectively. The Σ7OPEs content level is comparable to that of urban soil,which is worthy of attention. TBEP and TDCPP were the most abundant compounds in the plateau soil. Point source emissions have significant influence on the spatial distribution of OPEs, and regional deposition of OPEs contributes to all sampling sites. The migration ability of different OPE compounds in soil was different. Stronger migration ability was observed for aromatic OPEs (TPhP) than chlorinated OPEs. Principal component analysis showed that the main sources of OPEs in plateau soil were atmospheric wet and dry deposition, manufactured consumer materials, and the release of OPEs from automobile interior decoration.


Asunto(s)
Retardadores de Llama , China , Monitoreo del Ambiente , Ésteres , Retardadores de Llama/análisis , Organofosfatos , Suelo , Tibet
12.
Zhongguo Gu Shang ; 34(1): 26-33, 2021 Jan 25.
Artículo en Chino | MEDLINE | ID: mdl-33666016

RESUMEN

OBJECTIVE: To establish a three-dimensional finite element model of osteoporosis and to study the stiffness recovery of injured vertebrae and stress analysis of adjacent vertebrae after percutaneous vertebroplasty under different perfusion and distribution conditions by simulating fluid flow into the vertebral body. METHODS: A male healthy volunteer was selected. CT scans were performed from T11 to L2. Mimics 15.0 and ABAQUS 6.11 software were used to extract CT images. The vertebral model of osteoporotic fracture was established. The flow physical field and conduction and diffusion physical field were coupled to simulate the process and parts of the injection of bone cement into the vertebral fracture model. The amount of bone cement injected into the vertebral fracture model was 2 ml, 4 ml, 6 ml respectively. The diffusion range of bone cement was simulated on the image, and the post injection model of bone cement was obtained. Vertical downward, forward and backward pressure of 300 N were applied on the surface of the model to simulate vertebral movement. The stress changes of upper and lower vertebrae and diseased vertebrae under different conditions were calculated. RESULTS: (1) The VonMises stress of T12 inferior endplate was the largest in the three states before and after fracture.(2) The VonMises stress of the intervertebral disc and each endplate after fracture was significantly higher than before fracture. When percutaneous vertebroplasty was applied, as the amount of bone cement injection increases, the VonMises stress of the adjacent vertebral endplates increases. In the diseased vertebrae, as the amount of bone cement increases, the VonMises stress of the vertebral body endplate showed a downward trend. CONCLUSION: Reliable biomechanical model of lumbar vertebral fracture can be established by using CT scanning data through software simulation. Vertebral fracture and vertebroplasty will cause biomechanical changes of adjacent vertebral bodies. With the increase of bone cement injection, the influence of biomechanical changes will increase significantly. Neighbouring vertebral fractures are more likely. For this experiment, percutaneous vertebroplasty has a suitable amount of cement injection of 4 ml.


Asunto(s)
Fracturas por Compresión , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Vertebroplastia , Fenómenos Biomecánicos , Cementos para Huesos , Análisis de Elementos Finitos , Fracturas por Compresión/cirugía , Humanos , Vértebras Lumbares/cirugía , Masculino , Fracturas Osteoporóticas/cirugía , Fracturas de la Columna Vertebral/cirugía
13.
J Med Ultrason (2001) ; 47(3): 453-462, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32306192

RESUMEN

PURPOSE: To evaluate the diagnostic value of shear wave elastography (SWE) combined with contrast-enhanced ultrasonography (CEUS) in diagnosing thyroid imaging reporting and data system (TI-RADS) category 4a and 4b nodules. METHODS: TI-RADS, SWE, and CEUS features of 71 thyroid nodules (23 benign, 48 malignant) confirmed by postoperative pathological results were retrospectively analyzed. The diagnostic efficiency of each single method and that of a combination of three methods were compared. RESULTS: The sensitivity and specificity in diagnosing thyroid nodules were 70.83% and 65.22% for TI-RADS, 68.75% and 91.30% for SWE, 77.08% and 78.26% for CEUS, and 91.67% and 95.65% for TI-RADS + SWE + CEUS, respectively. The area under the curve for TI-RADS, SWE, CEUS, and TI-RADS + SWE + CEUS in diagnosing thyroid nodules were 0.680, 0.839, 0.799, and 0.937, respectively. A significant difference was observed between a combination of the three methods and any of them alone (p < 0.05). CONCLUSION: Combining SWE and CEUS improves the differential diagnosis of TI-RADS category 4a and 4b nodules.


Asunto(s)
Medios de Contraste , Aumento de la Imagen/métodos , Nódulo Tiroideo/diagnóstico por imagen , Nódulo Tiroideo/patología , Ultrasonografía/métodos , Adulto , Anciano , Diagnóstico Diferencial , Diagnóstico por Imagen de Elasticidad/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Imagen Multimodal/métodos , Sistemas de Información Radiológica , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad , Glándula Tiroides/diagnóstico por imagen , Glándula Tiroides/patología , Adulto Joven
14.
BMC Surg ; 20(1): 66, 2020 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-32252742

RESUMEN

BACKGROUND: The development of adjacent segment degeneration (ASD) following ACDF is well established. There is no analytical study related to effects of plate profile on the biomechanics of the adjacent-level after ACDF. This study aimed to test the effects of plate profile on the adjacent-level biomechanics after single-level anterior cervical discectomy and fusion (ACDF). METHODS: A three-dimensional finite element model (FEM) of an intact C2-T1 segment was built and validated. From this intact model, two instrumentation models were constructed with the anchored zero-profile spacer or the standard plate-interbody spacer after a C5-C6 corpectomy and fusion. Motion patterns, the stresses in the disc, the endplate, and the facet joint at the levels cephalad and caudal to the fusion were assessed. RESULTS: Compared with the normal condition, the biomechanical responses in the adjacent levels were increased after fusion. Relative to the intact model, the average increase of range of motion (ROM) and stresses in the endplate, the disc, and the facet of the zero-profile spacer fusion model were slightly lower than that of the standard plate-interbody spacer fusion model. The kinematics ROM and stress variations above fusion segment were larger than that below. The biomechanical features of the adjacent segment after fusion were most affected during extension. CONCLUSIONS: The FE analysis indicated that plate profile may have an impact on the biomechanics of the adjacent-level after a single-level ACDF. The impact may be long-term and cumulative. The current findings may help explain the decreasing incidence of ASD complications in the patients using zero-profile spacer compared with the patients using cage and plate construct.


Asunto(s)
Vértebras Cervicales/cirugía , Discectomía/métodos , Análisis de Elementos Finitos , Fusión Vertebral/métodos , Adulto , Fenómenos Biomecánicos , Placas Óseas , Humanos , Masculino , Rango del Movimiento Articular
15.
Huan Jing Ke Xue ; 40(12): 5265-5271, 2019 Dec 08.
Artículo en Chino | MEDLINE | ID: mdl-31854597

RESUMEN

To study the pollution characteristics and exposure health risk of perfluoroalkyl substances (PFASs) in road dust, 12 PFASs were analyzed by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) in this study. PFAS concentrations in road dust ranged from 0.95 to 111 ng·g-1, with an average concentration of (25.6±37.2) ng·g-1, suggesting large spatial differences between PFASs in road dust. PFAS concentrations on the main roads were significantly higher than on minor roads, and the minor roads downtown displayed higher concentration levels than suburban minor roads. Perfluorobutanoic acid (PFBA) was the predominant compound in Section 1 of Jie-fang Road, Jin-niu-ba Road and Shui-nian-he Road, while perfluroroocantanoic acid (PFOA, 24.8%) and perfluorooctane sulfonate (PFOS, 24.1%) were the main PFASs on other roads, indicating different sources of PFASs in these areas. The total daily dose of PFASs in road dust for children and adults were 0.168 ng·(kg·d)-1 and 0.028 ng·(kg·d)-1, respectively, suggesting higher exposure risk for children than adults. Therefore, more attention should be paid to children's health risk assessment. Daily doses of PFOA and PFOS in road dust for Chengdu residents were lower than the maximum daily intakes recommended by the European Authority, indicating that there was no immediate health risk to local residents.


Asunto(s)
Ácidos Alcanesulfónicos , Fluorocarburos , Medición de Riesgo , Adulto , Niño , Cromatografía Liquida , Polvo , Humanos , Espectrometría de Masas en Tándem
16.
Huan Jing Ke Xue ; 40(9): 4295-4302, 2019 Sep 08.
Artículo en Chino | MEDLINE | ID: mdl-31854897

RESUMEN

In order to study the effects of atmospheric transport and the wet/dry deposition on the content and distribution of organophosphate esters (OPEs) in remote areas, seven types of OPEs including tri-n-butyl phosphate (TnBP), tri (2-chloroethyl) phosphate (TCEP), trichloropropyl phosphate (TCPP), tridichloropropyl phosphate (TDCPP), triphenyl phosphate (TPhP), tributoxyethyl phosphate (TBEP), and tris (2-ethylhexyl) phosphate (TEHP) were analyzed in plants and snow samples in Hailuogou using gas chromatography-mass spectrometry. The results showed that the pollution levels of the seven OPEs (∑7OPEs) in the plant samples ranged from 43.1 ng·g-1 to 1050.8 ng·g-1. TBEP and TPhP were the main pollutants, accounting for 36%-70% and 24%-80% of the ∑7OPEs, respectively. The main pollutants in the snow in Hailuogou were the same as those in the plants, with TBEP dominating the profile of the ∑7OPEs at 47%, followed by TPhP at 24%. The analysis results of the grid analysis display system (Grads), backward trajectory model, and historical wind data of Hailuogou indicate that the OPEs in this region are affected mainly by atmospheric transmission from Chengdu and the junction of Yunnan Zhaotong and Yibin, Luzhou, and Xichang. The environment of Hailuogou has obviously been disturbed by human activities. It is necessary to conduct thorough investigations of its environmental behavior and to strengthen urban pollution control measures.

17.
Huan Jing Ke Xue ; 40(3): 1245-1251, 2019 Mar 08.
Artículo en Chino | MEDLINE | ID: mdl-31087971

RESUMEN

New GC-MS methods were developed for seven typical organophosphate esters (OPEs) including tri-n-butyl phosphate (TnBP), tris (2-ethylhexyl) phosphate (TEHP), tributoxyethyl phosphate (TBEP), triphenyl phosphate (TPhP), tri (2-chloroethyl) phosphate (TCEP), trichloropropyl phosphate (TCPP) and tridichloropropyl phosphate (TDCPP). These methods were used to quantify their concentrations in the surface water and sediment from the Jinjiang River, Chengdu. The recoveries of the target substances were 76%-119% (surface water)and 83%-126% (sediments). Total OPEs (Σ7OPEs) ranged from 689.09 to 10623.94 ng·L-1, with the mean of 3747.58 ng·L-1 in the surface water. The pollution level of each monomer was in the order TBEP > TCEP > TPhP > TEHP > TCPP > TnBP. TBEP was the predominant pollutant, accounting for 36.50%-95.90% of the Σ7OPEs concentrations. The contents (dw) of the Σ7OPEs ranged from 25.52 to 296.00 ng·g-1 in sediments, and TBEP was also the main pollutant in these samples. No significant correlation existed between the concentrations of OPEs in the surface water and sediments. Alkyl OPEs were the main pollutants in the surface water and sediments. The distribution of OPEs was influenced by the source of emissions and environmental attributes. The pairs TCPP and TnBP, TBEP and TEHP, and TCEP and TPhP might have common sources in the surface water.

18.
Huan Jing Ke Xue ; 38(11): 4868-4873, 2017 Nov 08.
Artículo en Chino | MEDLINE | ID: mdl-29965434

RESUMEN

Using ultrasonic assisted extraction, column chromatograph purification and gas chromatograph-mass spectrometer(GC-MS) analysis method to quantify the contents of seven kinds of organic phosphorus ester(OPEs) in plastic tracks in Chengdu City. The recovery rates of this method ranged from 71.41% to 110.58% and the correlation coefficient (r) of the standard curve was higher than 0.99, which demonstrates satisfying quality control. Plastic track samples were collected from twelve schools in Chengdu. The results show that OPEs are detected in two-thirds of plastic track samples. TnBP[Tri-n-butyl phosphate] and TEHP[tris(2-ethylhexyl) phosphate] were detected with high frequency, while TCEP[tri(2-chloroethyl) phosphate], TDCPP[tridichloropropyl phosphate] and TPhP[triphenyl phosphate] were not detected in any samples. Contents of the total OPEs (Σ7OPEs) in the plastic track ranged from ND to 534.89 ng·g-1. TnBP was identified at the highest content levels (ND-462.18 ng·g-1). TCPP[Trichloropropyl phosphate], a chlorinated phosphate with higher toxicity, was detected in one sample with a contents of 205.94 ng·g-1. The average exposure dose for adults was 0.14 ng·(kg·d)-1, lower than that for children of 0.64 ng·(kg·d)-1. Risk quotients of OPEs for adults and children were only 10-7 -10-5 and could be ignored. These results indicate that the government should limit the consumption, as well as the type of OPEs which are added to plastic tracks, to protect population health.


Asunto(s)
Ésteres/análisis , Fósforo/análisis , Plásticos , Adulto , Niño , Monitoreo del Ambiente , Cromatografía de Gases y Espectrometría de Masas , Humanos , Medición de Riesgo
19.
Huan Jing Ke Xue ; 36(10): 3566-72, 2015 Oct.
Artículo en Chino | MEDLINE | ID: mdl-26841586

RESUMEN

Organic phosphorus esters ( OPEs ) in atmospheric PM2.5 in Chengdu city was quantitatively determined by using gas chromatography-mass spectrometry. The distribution characteristic was discussed, back trajectory model and correlation analysis were used to study the sources of OPEs in PM2.5 in Chengdu city. The results showed that the annual average concentration of Σ7OPEs in atmospheric PM2.5 in Chengdu city was 6.46 ng x m(-3) for the urban site and was 9.38 ng x m(-3) for the suburb site. Due to the waste material recycling industries in the suburb area and the perennial dominant wind direction in Chengdu, the concentration of Σ7OPEs at suburb site was higher than that at urban site (P = 0.013). The atmospheric mixed degree influenced the distribution of OPEs in rural and urban area. The source of Σ7OPEs in atmospheric PM2.5 in Chengdu city was mainly from endogenous pollution which was mainly affected by the local sources around the samoling sites. while the contribution of the exogenous pollution was small.


Asunto(s)
Contaminantes Atmosféricos/análisis , Ésteres/análisis , Material Particulado/análisis , Fósforo/análisis , China , Ciudades , Monitoreo del Ambiente
20.
Huan Jing Ke Xue ; 32(11): 3277-83, 2011 Nov.
Artículo en Chino | MEDLINE | ID: mdl-22295624

RESUMEN

The levels and congener patterns of 28 PCBs compounds were investigated in soil and dust fallout collected in a capacitor storage site and an industrial brownfield, respectively in Sichuan Ziyang Locomotive Factory. The highest concentration of the total PCBs(sigma PCBs =227 502 ng x g(-1)) was found in soil collected from the front gate (unsealed) of the capacitor storage tunnel. Very high levels of sigma PCBs, exceed 10 microg x g(-1), were also found in the dust collected from the window sill of an iron foundry. There were significant positive correlations (P < 0.01) among PCB congener concentration in the storage site and the iron foundry samples. The major contribution to the total content of PCBs in the high contaminated samples was tetrachlorinated biphenyls, followed by tri- and penta-chlorinated biphenyls. Hexa- and higher chlorinated biphenyls contributed more to sigma PCBs in the iron foundry than those in the storage site. The total toxicity equivalents (TEQ) of 12 dioxin-like congeners varied in the range of 75.43-24 027 pg x g(-1) and were much higher than those in soils of e-waste recycling sites. However, PCB126 contribute the most to the TEQ in most cases.


Asunto(s)
Contaminantes Ambientales/análisis , Bifenilos Policlorados/análisis , Bifenilos Policlorados/química , Suelo/análisis , China , Polvo/análisis , Monitoreo del Ambiente , Residuos Industriales
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