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1.
J Nanosci Nanotechnol ; 20(2): 673-679, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383062

RESUMO

A proper soft tissue seal between implants and gingiva is critical for success of dental implants. Implant surface modification is an important approach for achieving ideal host-implant integration. In this study, we used a new and simple oxidation method to generate a rough surface on implants at the nano scale, which oxidized titanium nano-foveolae (TiNF) surface. We further analyzed the surface topography and tested its effects on biological activities of human gingival fibroblasts. Atomic force microscopy (AFM) and scanning electron microscopy (SEM) examination demonstrated that TiNF disks displayed uniform rough surfaces, with average TiNF diameters of approximately 60 nm and 100 nm respectively. However, the surfaces of smooth samples were highly irregular, and cell adhesion and proliferation rates on TiNF surfaces were significantly higher than those of the smooth surfaces. Extracellular matrix synthesis was also increased in the cells that interacted with oxidized TiNF surfaces. Altogether, these results suggest that the TiNF implant surfaces perform better for human gingival fibroblast biological activities compared to traditional smooth surfaces. Therefore, the TiNF implant surfaces may serve as ideal interface to facilitate implant-host integration.

2.
Stroke ; 49(9): 2074-2080, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30354984

RESUMO

Background and Purpose- The aim of the study was to investigate the utility of iodine contrast agent leakage (the iodine sign) analyzed by Gemstone spectral imaging in early hematoma formation compared with that of the spot sign for predicting early hematoma expansion (HE) and poor functional outcomes. Methods- From 2014 to 2017, 91 patients with spontaneous intracerebral hemorrhage who underwent spectral computed tomography angiography within 6 hours of spontaneous intracerebral hemorrhage onset were prospectively included in our study. We defined a positive iodine sign as tiny enhancing foci within the hematoma on Gemstone spectral imaging and an iodine concentration inside the foci of >7.82 (100 µg/mL). Univariate and multivariate logistical regression analyses were performed to assess risk factors for HE, and the predictive value of HE was analyzed. Results- Positive spot and iodine signs were present in 38.5% (35/91) and 57.1% (52/91) of the patients, respectively. Using multivariate analysis, the iodine sign independently predicted HE (odds ratio, 53.67; 95% CI, 11.88-242.42; P<0.001) and had a higher sensitivity (91.5% versus 63.8%), negative predictive value (89.7% versus 69.9%), and accuracy (85.7% versus 75.8%) for detecting HE than the spot sign. The iodine sign, but not the spot sign, was significantly related to poor functional outcomes (severely disabled and vegetative state) in all patients (χ2=29.97; P<0.001). Conclusions- The iodine sign is a reliable and sensitive marker for predicting HE and poor functional outcomes. Clinical Trial Registration- URL: https://www.clinicaltrials.gov . Unique identifier: NCT02625948.

4.
J Mater Sci Mater Med ; 29(9): 141, 2018 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-30120576

RESUMO

Ti-based implants sometimes fail to integrate with surrounding bone tissue due to insufficiency of new bone formation and surface bonding. To overcome this problem, this research focused on establishing a sustained bone growth factor delivery system by applying anodized TiO2 nanotube arrays and PLGA film on the titanium implant surface. TiO2 nanotube arrays were made by anodic oxidation method, and were then filled with rhBMP2 by vacuum freeze-drying. Next, PLGA was deposition on the surface of this material. The designed system was characterized, pharmacokinetic release rate of rhBMP2 was determined. Adhesion, proliferation, and differentiation activity of osteoblasts cultured on the new surfaces and traditional titanium surfaced were compared. SEM showed that a surface of TiO2 nanotube arrays were successfully generated. PLGA membranes of 50 nm, 250 nm, 800 nm thickness were successfully deposited on the surfaces of TiO2 nanotube layers by using 1%, 3%, 10% PLGA solutions. PLGA film of 250 nm thickness showed ideally controlled release of rhBMP2, lasting for 4 weeks. Furthermore, 250 nm thickness PLGA film improved osteoblast adhesion, proliferation, and levels of alkaline phosphatase. In conclusion, the PLGA film / TiO2 nanotube growth factor delivery system can effectively sustain the release of rhBMP-2, and promote proliferation and differentiation of MC3T3-E1 osteoblasts.

5.
Acta Radiol ; : 284185118780893, 2018 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-29871494

RESUMO

Background Positive "dynamic spot sign" has been proven to be a potential risk factor for acute intracerebral hemorrhage (ICH) expansion, but local perfusion change has not been quantitatively investigated. Purpose To quantitatively evaluate perfusion changes at the ICH area using computed tomography perfusion (CTP) imaging. Material and Methods Fifty-three patients with spontaneous ICH were recruited. Unenhanced computed tomography (NCCT), CTP within 6 h, and follow-up NCCT were performed for 21 patients in the "spot sign"-positive group and 32 patients in the control group. Cerebral perfusion change was quantitatively measured on regional cerebral blood flow/regional cerebral blood volume (rCBF/rCBV) maps. Regions of interest (ROIs) were set at the "spot-sign" region and the whole hematoma area for "spot-sign"-positive cases, and at one of the highest values of three interested areas and the whole hematoma area for the control group. Hematoma expansion was determined by follow-up NCCT. Results For the "spot-sign"-positive group, the average rCBF (rCBV) values at the "spot-sign" region and the whole hematoma area were 21.34 ± 15.24 mL/min/100 g (21.64 ± 21.48 mL/100g) and 5.78 ± 6.32 mL/min/100 g (6.07 ± 5.45 mL/100g); for the control group, the average rCBF (rCBV) values at the interested area and whole hematoma area were 2.50 ± 1.83 mL/min/100 g (3.13 ± 1.96 mL/100g) and 3.02 ± 1.80 mL/min/100 g (3.40 ± 1.44 mL/100g), respectively. Average rCBF and rCBV values of the "spot-sign" region were significantly different from other regions ( P < 0.001; P = 0.004). The average volumes of hematoma expansion in the "spot-sign"-positive and control groups were 25.24 ± 19.38 mL and -0.41 ± 1.34 mL, respectively. Conclusion The higher perfusion change at ICH on CTP images may reflect the contrast extravasation and be associated with the hematoma expansion.

6.
Dalton Trans ; 47(28): 9257-9266, 2018 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-29901678

RESUMO

In this study, (Ba0.85Ca0.15)(Ti0.9Zr0.1)O3 (BCTZ) lead-free ceramics with enhanced energy density were prepared by two-step sintering. All ceramics fall into the rhombohedral-orthorhombic-tetragonal (R-O-T) phase boundary near room temperature, and a dense microstructure with an intermediate grain size was observed. The enhanced piezoelectric and energy harvesting properties were attained over a wide grain size range of 10-15 µm, benefiting from the construction of the R-O-T phase boundary. Most interestingly, the maximum values of d33 and d33 × g33 (530 pC N-1 and 9720 × 10-15 m2 N-1) can be achieved at 1500/1350 °C with a grain size of 13.7 µm. The interpretation of the underlying mechanism related to domain and defect engineering has been investigated systematically. Furthermore, a high output power of 99 µW and an energy conversion efficiency of 10% were obtained at a simple cantilever energy harvester fabricated from a 1500/1350 °C specimen under an acceleration of 1.0g, making the current system very promising for piezoelectric energy harvesting applications.

7.
Eur Radiol ; 28(10): 4343-4349, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29675658

RESUMO

OBJECTIVES: The computed tomography angiography (CTA) spot sign is a validated predictor of haematoma expansion (HE) in spontaneous intracerebral haemorrhage (SICH). We investigated whether defining the iodine concentration (IC) inside the spot sign and the haematoma on Gemstone spectral imaging (GSI) would improve its sensitivity and specificity for predicting HE. METHODS: From 2014 to 2016, we prospectively enrolled 65 SICH patients who underwent single-phase spectral CTA within 6 h. Logistic regression was performed to assess the risk factors for HE. The predictive performance of individual spot sign characteristics was examined via receiver operating characteristic (ROC) analysis. RESULTS: The spot sign was detected in 46.1% (30/65) of patients. ROC analysis indicated that IC inside the spot sign had the greatest area under the ROC curve for HE (0.858; 95% confidence interval, 0.727-0.989; p = 0.003). Multivariate analysis found that spot sign with higher IC (i.e. IC > 7.82 100 µg/ml) was an independent predictor of HE (odds ratio = 34.27; 95% confidence interval, 5.608-209.41; p < 0.001) with sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of 0.81, 0.75, 0.90 and 0.60, respectively; while the spot sign showed sensitivity, specificity, PPV and NPV of 0.81, 0.79, 0.73 and 0.86. Logistic regression analysis indicated that the IC in haematomas was independently associated with HE (odds ratio = 1.525; 95% confidence interval, 1.041-2.235; p = 0.030). CONCLUSIONS: ICs in haematoma and in spot sign were all independently associated with HE. IC analysis in spectral imaging may help to identify SICH patients for targeted haemostatic therapy. KEY POINTS: • Iodine concentration in spot sign and haematoma can predict haematoma expansion • Spectral imaging could measure the IC inside the spot sign and haematoma • IC in spot sign improved the positive predictive value (PPV) cf. CTA.


Assuntos
Hemorragia Cerebral/diagnóstico por imagem , Angiografia por Tomografia Computadorizada/métodos , Meios de Contraste , Extravasamento de Materiais Terapêuticos e Diagnósticos , Hematoma/diagnóstico por imagem , Iohexol , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Valor Preditivo dos Testes , Curva ROC , Fatores de Risco , Sensibilidade e Especificidade
8.
Clin Neurol Neurosurg ; 166: 141-146, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29427894

RESUMO

OBJECTIVES: Glioma is the most common malignant tumor of the brain and the intracranial dissemination of gliomas is the late stage of the development of the tumor. However, there is little research in literature on the occurrence of intracranial dissemination of gliomas. In order to provide a reference for clinical work, we carried out this study on intracranial dissemination of glioma. PATIENTS AND METHODS: A total of 629 patients with gliomas received tumor resection by the same surgeon from August 2010 to September 2015 were included in this study. The authors performed a retrospective review of the patients and the information regarding clinical features, histopathological results, molecular pathologic results and clinical outcomes was collected and analyzed. RESULTS: In this retrospective study, we found that the intracranial dissemination phenomenon occurred in 53 patients (8.43%). We analyzed the clinical characteristics of patients and found that the age at diagnosis (P = 0.011), WHO grade of the tumor (P < 0.001), and involvement of the corpus callosum (P = 0.010) were associated with the occurrence of dissemination. The higher grade of the tumor, the more prone to disseminate. Deletion of 1p/19q had no significant correlation with the intracranial dissemination. MMP9, Ki-67, and EGFR were highly expressed in tumor cells that caused dissemination, and the level of Ki-67 expression had significance in statistics (P < 0.01). CONCLUSION: In our study, older age (>40 years), high pathological grade, invasion of the corpus callosum and high levels of Ki-67 expression were risk factors associated with the intracranial dissemination of gliomas.

9.
Nanotechnology ; 29(4): 045101, 2018 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-29182157

RESUMO

Great effort has recently been devoted to the preparation of nanoscale surfaces on titanium-based implants to achieve clinically fast osteoinduction and osseointegration, which relies on the unique characteristics of the nanostructure. In this work, we used induction heating treatment (IHT) as a rapid oxidation method to fabricate a porous nanoscale oxide layer on the Ti6Al4V surface for better medical application. Well-distributed vertical nanopillars were yielded by IHT for 20-35 s on the alloy surface. The composition of the oxides contained rutile/anatase TiO2 and a small amount of Al2O3 between the TiO2 grain boundaries (GBs). This technology resulted in a reduction and subsequent increase of surface roughness of 26-32 nm when upregulating the heating time, followed by the successive enhancement of the thickness, wettability and adhesion strength of the oxidation layer to the matrix. The surface hardness also distinctly rose to 554 HV in the IHT-35 s group compared with the 350 HV of bare Ti6Al4V. The massive small-angle GBs in the bare alloy promoted the formation of nanosized oxide crystallites. The grain refinement and deformation texture reduction further improved the mechanical properties of the matrix after IHT. Moreover, in vitro experiments on a mesenchymal stem cell (BMSC) culture derived from human bone marrow for 1-7 days indicated that the nanoscale layers did not cause cytotoxicity, and facilitated cell differentiation in osteoblasts by enhancing the gene and osteogenesis-related protein expressions after 1-3 weeks of culturing. The increase of the IHT time slightly advanced the BMSC proliferation and differentiation, especially during long-term culture. Our findings provide strong evidence that IHT oxidation technology is a novel nanosurface modification technology, which is potentially promising for further clinical development.

10.
Oncol Lett ; 14(5): 5505-5512, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29113178

RESUMO

The majority of primary central nervous system lymphomas (PCNSLs) are diffuse large B cell lymphoma, characterized by poor prognosis. In the present study, the expression of cluster of differentiation (CD)10, B cell lymphoma (BCL)-6, multiple myeloma-1 (MUM-1), BCL-2, CD138 and Ki-67 was analyzed by immunohistochemistry in 89 Chinese PCNSL cases, and the potential prognostic significance was evaluated. CD10, BCL-6, MUM-1, BCL-2 and CD138 were positive in 16.9 (15/89), 51.7 (46/89), 92.1 (82/89), 73.3 (63/86) and 0% (0/65) of all cases, respectively. According to the Hans algorithm, 71 patients (79.8%) were classified into the non-germinal center B cell-like (non-GCB) group, indicating a post-germinal center origin of PCNSL. The median follow-up time of 73 patients was 13 months [95% confidence interval (CI), 10.93-15.08]. The median overall survival (OS) time was 45.3 months (95% CI, 25.01-65.59) and the median progression-free survival (PFS) time was 30.0 months (95% CI, 13.43-46.57). Age (>60 years) was associated with a shorter OS time (P=0.009). Ki-67 (cutoff point 90%) was associated with shorter OS (P=0.037) and shorter PFS (P=0.039) times. No other immunohistochemical markers were associated with prognosis. On multivariate analysis, age (>60 years) was associated with shorter OS time (P=0.038), but immunophenotype and expression status of Ki-67, CD10, BCL-6 and BCL-2 did not predict prognosis. In conclusion, high Ki-67 expression may predict poor prognosis in PCNSL. The present study was limited by its sample size and short follow-up time. This requires more evidence to further clinical study.

11.
J Oral Maxillofac Surg ; 75(8): 1722-1731, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28500874

RESUMO

PURPOSE: To determine whether low-dose recombinant human parathyroid hormone (rhPTH) would have a beneficial effect on regenerate healing and surrounding bone in a rabbit model of rapid mandibular distraction osteogenesis (DO). MATERIALS AND METHODS: Twenty-eight rabbits underwent unilateral mandibular lengthening at a rapid rate of 2 mm per day for 5 days. From the first day of DO, the experimental group received daily subcutaneous injections of rhPTH 10 µg/kg for 30 days and the control group received the same volume of saline (n = 14 in each group). At 6 weeks after completion of DO, the distracted callus was examined by micro-computed tomography (micro-CT), histology, and the 3-point bending test. Moreover, bone mineral density of the anterior pin region was evaluated by dual-energy x-ray absorptiometry. RESULTS: Under rapid distraction, poor bone healing was observed in the distracted callus from the control group. In contrast, more mature and abundant bone formation was found in the distracted callus from the experimental group by histologic and micro-CT examinations. Quantitatively, the PTH-treated animals had superior parameters in bone volume fraction, trabecular number, and trabecular thickness and mechanical properties compared with controls (P < .05). Bone mineral density of the anterior pin region was greater in the experimental than in the control group (P < .05). CONCLUSION: Low-dose intermittent rhPTH administration not only enhances new bone formation but also can prevent fixator-related osteoporosis of surrounding segments after rapid mandibular DO in rabbits.


Assuntos
Mandíbula/cirurgia , Avanço Mandibular/métodos , Osteogênese por Distração/métodos , Hormônio Paratireóideo/farmacologia , Animais , Relação Dose-Resposta a Droga , Esquema de Medicação , Masculino , Coelhos , Proteínas Recombinantes/farmacologia , Microtomografia por Raio-X
12.
Oncotarget ; 8(30): 49156-49164, 2017 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-28467782

RESUMO

PURPOSE: High-dose methotrexate based chemotherapy is the standard treatment for patients with newly diagnosed primary central nervous system lymphoma (PCNSL). The role of rituximab is controversial because of its large size, which limits its penetration of the blood-brain barrier. In this study, we investigated the efficacy and tolerability of adding rituximab to methotrexate-cytarabine-dexamethasone combination therapy (RMAD regimen). RESULTS: The patients treated with RMAD had a complete remission rate of 66.7% after induction chemotherapy; this rate was only 33.3% in patients treated with MAD alone (p = .011). The most common grade 1-3 adverse events were similar and included hematologic toxicity, increased aminotransferase levels, and gastrointestinal reactions. Multivariate analysis revealed that rituximab treatment was associated with longer progression-free survival (PFS, p = .005) but not overall survival (OS). Additionally, we observed that elevated serum lactate dehydrogenase was associated with shorter OS and PFS. MATERIALS AND METHODS: We retrospectively analyzed 60 immunocompetent patients with newly diagnosed PCNSL at Beijing Tiantan Hospital, Capital Medical University from January 2010 to June 2016. Twenty-four patients received 3-6 courses of 3.5 g/m2 methotrexate on day 1; 0.5-1 g/m2 cytarabine on day 2; and 5-10 mg dexamethasone on days 1, 2 and 3. Thirty-six patients received the same combination plus rituximab 375 mg/m2 on day 0. All patients repeated the treatment every 3 weeks. CONCLUSIONS: High-dose methotrexate based chemotherapy with rituximab yields a higher complete remission rate and does not increase serious toxicities. PFS benefits from the addition of rituximab. OS has an increasing trend in patients treated with rituximab without statistical significance.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias do Sistema Nervoso Central/tratamento farmacológico , Linfoma/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias do Sistema Nervoso Central/mortalidade , Criança , Citarabina/administração & dosagem , Dexametasona/administração & dosagem , Progressão da Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Linfoma/diagnóstico , Linfoma/mortalidade , Masculino , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Indução de Remissão , Rituximab/administração & dosagem , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
13.
Oncol Rep ; 37(2): 887-894, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27959415

RESUMO

The Src homology region 2 domain-containing phosphatase-1 (SHP1) is a critical negative regulator involved in the JAK/STAT signaling pathway. The SHP1 gene has been proposed as a candidate tumor suppressor in solid and hematological malignancies and promoter methylation is an important biological process in controlling tumorigenesis. However, the detailed roles of SHP1 promoter methylation in the pathogenesis of primary central nervous system lymphoma (PCNSL) is largely unknown. In the present study, we evaluated the correlation between SHP1 expression and promoter methylation in patients with PCNSL. Thirty-three patients with PCNSL were included. We evaluated SHP1 protein expression levels by immunohistochemistry and the SHP1 promoter methylation profile by pyrosequencing analysis. For cases (n=8) with a good yield of total protein, SHP1 phosphorylation (pSHP1) and STAT3 protein expression levels were further analyzed by western blot analysis to uncover the molecular impact of SHP1 promoter methylation on downstream signaling pathways. In this study, a lower expression of SHP1 protein level was observed in 16/33 cases (48.5%) of PCNSL. SHP1 promoter methylation was predominant in 29/33 cases (87.9%) with a mean methylation level of 31.7±36.5%. The mean methylation level of the SHP1 promoter was significantly elevated in patients with a lower SHP1 protein expression, compared with those showing a higher SHP1 protein expression (50.3±38.9 vs. 14.2±24.0%, p=0.004). Further analysis showed that SHP1 protein expression was significantly decreased in patients with a higher SHP1 promoter methylation status (p=0.001), and such attenuation was correlated with a downregulation of pSHP1 (p=0.005) and an upregulation of STAT3 protein expression (p=0.020). Our data demonstrated that epigenetic alterations in the promoter region downregulated SHP1 expression in PCNSL patients. SHP1 promoter methylation was correlated with tyrosine phosphorylation and activation of transcription factor STAT3, which may contribute to the pathogenesis of PCNSL. Therapeutical regimens with epigenetic modifiers may be a potential option for patients with PCNSL.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias do Sistema Nervoso Central/genética , Metilação de DNA , Regulação Neoplásica da Expressão Gênica , Linfoma não Hodgkin/genética , Regiões Promotoras Genéticas/genética , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Biomarcadores Tumorais/metabolismo , Western Blotting , Neoplasias do Sistema Nervoso Central/metabolismo , Neoplasias do Sistema Nervoso Central/patologia , Feminino , Seguimentos , Humanos , Técnicas Imunoenzimáticas , Linfoma não Hodgkin/metabolismo , Linfoma não Hodgkin/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Fosforilação , Prognóstico , Proteína Tirosina Fosfatase não Receptora Tipo 6/metabolismo , Estudos Retrospectivos , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transdução de Sinais
14.
Oncol Lett ; 14(6): 8162-8170, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29344259

RESUMO

The present study aimed to characterize the specific pathology and magnetic resonance imaging (MRI) findings observed in patients with leukemia with central nervous system (CNS) lesions, and to determine their value in the management of such patients. Lesions of the CNS were observed during and following treatment of leukemia. The data from stereotactic biopsy-proven pathology (12 patients) and MRI examinations (14 patients) were retrospectively evaluated. Proton-magnetic resonance-spectroscopy was performed in three patients. Factors that predisposed to lesions of the CNS were reviewed from the patient medical records. Among the 14 patients, eight had CNS leukemia, four had a CNS infection and two had a neurodegenerative disorder (one leukoencephalopathy and one glial cell hyperplasia). The clinical diagnosis based on clinical symptoms, signs and MRI features was not consistent with the pathological diagnosis in two patients. In one patient, the clinical diagnosis was a CNS infection; however, the patient's pathological diagnosis was CNS leukemia. In the other patient, the clinical diagnosis was CNS leukemia, but the pathological diagnosis was glial cell hyperplasia. CNS lesions in leukemia have a wide range of causes. Apart from the relapse of leukemia in the CNS, there are treatment-associated neurotoxicities and infections that are caused by immunocompromised states. As numerous leukemia-associated CNS lesions are treatable, early diagnosis is essential.

15.
Acta Radiol ; 56(3): 347-54, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24676083

RESUMO

BACKGROUND: Histopathological studies have shown significant differences in plaque components and surface conditions between upstream and downstream of the stenosis. It can be deduced that the flow status near the plaques is different from the flow status at the upstream side, stenosis center, or downstream side of the plaque. PURPOSE: To study the hemodynamic parameter distribution in different locations near atherosclerotic plaques in the carotid arteries with different stenosis degrees. MATERIAL AND METHODS: Eleven patients were recruited in this study. CE-MRA was performed to obtain the carotid three-dimensional surface data and the stenosis degrees were calculated. The hemodynamic parameters including wall shear stress (WSS), pressure, and velocity near the plaques were obtained by computational fluid dynamic (CFD) method. Local hemodynamics parameters were analyzed and compared between different stenosis degree groups, and between upstream, stenosis center, and downstream sides of plaques. Relative ratio of velocity, WSS, and pressure values in different locations was calculated and compared. RESULTS: Fourteen carotid arteries (with 4 mild, 6 moderate, and 4 severe stenosis) were analyzed. Significant differences were found in Pressure max (P = 0.025), Pressure mean (P = 0.020), and Pressure min (P = 0.026) between three stenosis groups. It showed significant differences in Vmin (P < 0.001) and WSSmin (P < 0.001) between three different locations. It showed upstream to downstream ratio of WSSmax (P = 0.034) and WSSmean value (P = 0.042) was significantly different between mild and moderate/severe groups. Significant differences were found in upstream to stenosis center ratio of Pressure max value (P = 0.018), Pressure mean value (P = 0.029), and Pressure min value (P = 0.026), as well as in stenosis center to downstream ratio of Pressure min value (P = 0.042). CONCLUSION: Velocity, WSS, pressure, and relative ratio of these parameters have certain trends in distribution around the plaques in the carotid arteries.


Assuntos
Doenças das Artérias Carótidas/fisiopatologia , Hemodinâmica , Angiografia por Ressonância Magnética/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Velocidade do Fluxo Sanguíneo/fisiologia , Artérias Carótidas/fisiopatologia , Simulação por Computador , Meios de Contraste , Feminino , Humanos , Aumento da Imagem/métodos , Imagem Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Modelos Cardiovasculares , Fluxo Sanguíneo Regional/fisiologia , Índice de Gravidade de Doença
16.
Acta Neurochir (Wien) ; 156(3): 515-25, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24420008

RESUMO

OBJECTIVES: The purpose of this study was to investigate vessel wall imaging features combined with the luminal shapes of intracranial dissecting aneurysms (IDAs) by using 3 Tesla (3T) high-resolution magnetic resonance imaging (MRI) and digital subtraction angiography (DSA). METHODS: Sixty-seven patients with 76 IDAs were consecutively enrolled in the study from December 2011 to May 2013. DSA was performed to diagnose an IDA and to categorize its angiography patterns into either aneurysmal dilation, steno-occlusive, combined, or unclassifiable. Images of 3T high-resolution MRI were used to evaluate arterial wall imaging features of each lesion. Chi-squared tests were used for statistical analyses. RESULTS: Aneurysmal dilation (51 of 76, [67%]) was the most common angiography pattern of IDAs, followed by the combined pattern (20 of 76, [26%]). Seven percent (five of 76) of IDAs showed steno-occlusive (n = 3) and unclassifiable (n = 2) angiography patterns, in which intramural hematomas were detected in the arterial wall without luminal connection. Intimal flaps (32 of 76, [42%]), double-lumen sign (38 of 76, [50%]) and intramural hematomas (46 of 76, [61%]) were recognized as the characteristic features of dissection by high-resolution MRI. Intramural hematomas occurred more frequently in the combined patterns group (16 of 20, [80 %]) than in the aneurysmal dilation group (25 of 51, [49%]) (P = .017), while the occurrence of intimal flaps and double-lumen sign did not differ between angiographic patterns (P > .05). CONCLUSIONS: 3T high-resolution MRI combined with DSA offered clear visualization of vessel wall features and accurate assessment of the vessel lumen in IDAs. This combined approach would be highly useful for understanding the underlying pathological status of IDAs and in guiding treatment choices.


Assuntos
Aneurisma Dissecante/diagnóstico , Angiografia Digital/métodos , Aneurisma Intracraniano/diagnóstico , Angiografia por Ressonância Magnética/métodos , Humanos , Aumento da Imagem/métodos , Imagem por Ressonância Magnética/métodos
17.
J Virol ; 87(22): 12457-70, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24027324

RESUMO

The nucleoprotein (N) and phosphoprotein (P) interaction of nonsegmented negative-strand RNA viruses is essential for viral replication; this includes N°-P (N°, free of RNA) interaction and the interaction of N-RNA with P. The precise site(s) within N that mediates the N-P interaction and the detailed regulating mechanism, however, are less clear. Using a human parainfluenza virus type 3 (HPIV3) minigenome assay, we found that an N mutant (N(L478A) did not support reporter gene expression. Using in vivo and in vitro coimmunoprecipitation, we found that N(L478A) maintains the ability to form N(L478A)°-P, to self-assemble, and to form N(L478A)-RNA but that N(L478A)-RNA does not interact with P. Using an immunofluorescence assay, we found that N-P interaction provides the minimal requirement for the formation of cytoplasmic inclusion bodies, which contain viral RNA, N, P, and polymerase in HPIV3-infected cells. N(L478A) was unable to form inclusion bodies when coexpressed with P, but the presence of N rescued the ability of N(L478A) to form inclusion bodies and the transcriptional function of N(L478A), thereby suggesting that hetero-oligomers formed by N and N(L478A) are functional and competent to form inclusion bodies. Furthermore, we found that N(L478A) is also defective in virus growth. To our knowledge, we are the first to use a paramyxovirus to identify a precise amino acid within N that is critical for N-RNA and P interaction but not for N(0)-P interaction for the formation of inclusion bodies, which appear to be bona fide sites of RNA synthesis.


Assuntos
Citoplasma/metabolismo , Corpos de Inclusão/metabolismo , Nucleoproteínas/metabolismo , Vírus da Parainfluenza 3 Humana/metabolismo , Fosfoproteínas/metabolismo , RNA Viral/metabolismo , Transcrição Genética , Sequência de Aminoácidos , Animais , Células Cultivadas , Fibroblastos/metabolismo , Fibroblastos/virologia , Genoma Viral , Células HeLa , Humanos , Macaca mulatta , Dados de Sequência Molecular , Nucleoproteínas/genética , Fosfoproteínas/genética , RNA Viral/genética , Infecções por Respirovirus/metabolismo , Infecções por Respirovirus/virologia , Homologia de Sequência de Aminoácidos , Replicação Viral
18.
Brain Inj ; 27(7-8): 951-6, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23789869

RESUMO

BACKGROUND: Penetrating orbital injuries constitute a significant threat to ocular and cerebral structures. The incidence of central nervous system damage from orbital injury is related to the orbital anatomy and the characteristics of the penetrating object. Penetrating orbital injuries involving the brain stem are extremely rare. OBJECTIVES: To present an uncommon case of penetrating orbital injury and to discuss surgical management. CASE STUDY: A patient suffered from a penetrating injury by a Bakelite comb which extended from his left orbit through the cavernous sinus to the pons. Complete occlusion of the left cavernous segment of the internal carotid artery was detected and a frontotemporal craniotomy with lateral superior orbitotomy was performed to remove the object. A delayed asymptomatic carotid-cavernous fistula was identified 1 year later. CONCLUSION: Surgical treatment remains the mainstay of intervention for penetrating orbitocranial injuries. The rationale of surgical removal of a foreign body should focus on safe exposure and removal of the object at the earliest without inflicting further injuries. Close follow-up for a delayed carotid-cavernous fistula is necessary.


Assuntos
Blefaroptose/fisiopatologia , Tronco Encefálico/fisiopatologia , Craniotomia/métodos , Corpos Estranhos/cirurgia , Traumatismos Cranianos Penetrantes/cirurgia , Órbita/cirurgia , Plásticos , Adulto , Cegueira , Tronco Encefálico/lesões , Traumatismos Cranianos Penetrantes/fisiopatologia , Humanos , Masculino , Órbita/lesões , Resultado do Tratamento
19.
Eur Radiol ; 23(7): 1846-54, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23508276

RESUMO

OBJECTIVES: To evaluate the association between dynamic progressive enhancing foci ("dynamic spot sign") in acute haematoma on CT perfusion source images (CTP-SI) and haematoma expansion. METHODS: One hundred twelve consecutive patients with spontaneous intracerebral haemorrhage according to unenhanced CT, CTP and CT angiography within 6 h of symptom onset were prospectively evaluated. Patients were dichotomised according to the presence/absence of the dynamic spot sign on CTP-SI in haematoma. The predictive value of haematoma expansion was analysed. RESULTS: Haematoma expansion was detected in 28 patients (25.0 %) on follow-up unenhanced CT images. Thirty patients (26.8 %) demonstrated the dynamic spot sign on CTP-SI, about 83.3 % of patients with haematoma expansion (P < 0.001). Sensitivity, specificity, positive predictive value, negative predictive value and kappa value for expansion were 89.3 %, 94.0 %, 96.3 %, 83.3 % and 0.814, respectively. In multiple regression, the presence of the CTP dynamic spot sign within acute haematomas independently predicted haematoma expansion; the univariate analysis OR value was 131.667 (29.386-590.289), P < 0.0001. Moreover, the multivariate analysis CTP dynamic spot sign OR value was 203.996 (32.123-1295.488), P < 0.0001. CONCLUSIONS: The CTP-SI dynamic spot sign is associated with acute haematoma expansion, is more direct in showing active ongoing bleeding and has a higher predictive value than the CTA spot sign. KEY POINTS: • It is important to identify potential progression of spontaneous intracerebral haemorrhage. • Dynamic enhancement within CT perfusion source images is associated with haemorrhage expansion. • The CTP dynamic spot sign may be present throughout arterial to venous phase imaging. • The CTP dynamic spot sign carries a higher predive value for haematoma expansion than CTA.


Assuntos
Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/diagnóstico , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Angiografia Cerebral/métodos , Feminino , Hematoma/diagnóstico , Hematoma/diagnóstico por imagem , Hemorragia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Perfusão , Valor Preditivo dos Testes , Estudos Prospectivos , Análise de Regressão , Sensibilidade e Especificidade
20.
J Mater Sci Mater Med ; 24(4): 1079-91, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23371766

RESUMO

TiO2 anodized nanotubelayers are potentially useful for orthopedic and dental implants because they promotes bone formation. Peptide sequences, such as lysine-arginine-serine-arginine (KRSR), are often used to modify biomaterial surfaces for the selective adhesion of bone cells. The objective of this study was to functionalize TiO2 nanotube layers with KRSR to examine the responses of mouse preosteoblasts (MC3T3-E1) to this new material in vitro. SEM, AFM, XPS were used to characterize the materials. Immunofluorescence staining, SEM, ALP, RT-PCR, Wb analysis were used to detect the preosteoblast adhesion, spreading and osteogenic differentiation. KRSR peptides could be immobilized on the TiO2 nanotube layers by silane coupling. Immobilized KRSR increased preosteoblast adhesion and spreading on TiO2 nanotube layers. Moreover, osteogenic differentiation increased on the KRSR-modified TiO2 nanotube layers. KRSR-modified TiO2 nanotube layers have satisfactory biological properties and should be further investigated as medical implant materials.


Assuntos
Adesão Celular , Expressão Gênica , Nanotubos , Oligopeptídeos/química , Osteoblastos/citologia , Osteogênese/genética , Titânio/química , Western Blotting , Proliferação de Células , Perfilação da Expressão Gênica , Microscopia de Força Atômica , Microscopia Eletrônica de Varredura , Osteoblastos/enzimologia , Osteoblastos/metabolismo
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