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1.
J Am Chem Soc ; 146(3): 1935-1945, 2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38191290

RESUMO

The reaction mechanism of CO2 electroreduction on oxide-derived copper has not yet been unraveled even though high C2+ Faradaic efficiencies are commonly observed on these surfaces. In this study, we aim to explore the effects of copper anodization on the adsorption of various CO2RR intermediates using in situ surface-enhanced infrared absorption spectroscopy (SEIRAS) on metallic and mildly anodized copper thin films. The in situ SEIRAS results show that the preoxidation process can significantly improve the overall CO2 reduction activity by (1) enhancing CO2 activation, (2) increasing CO uptake, and (3) promoting C-C coupling. First, the strong *COO- redshift indicates that the preoxidation process significantly enhances the first elementary step of CO2 adsorption and activation. The rapid uptake of adsorbed *COatop also illustrates how a high *CO coverage can be achieved in oxide-derived copper electrocatalysts. Finally, for the first time, we observed the formation of the *COCHO dimer on the anodized copper thin film. Using DFT calculations, we show how the presence of subsurface oxygen within the Cu lattice can improve the thermodynamics of C2 product formation via the coupling of adsorbed *CO and *CHO intermediates. This study advances our understanding of the role of surface and subsurface conditions in improving the catalytic reaction kinetics and product selectivity of CO2 reduction.

2.
J Membr Biol ; 257(1-2): 107-114, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38285126

RESUMO

Osteoarthritis is a common joint disease characterized by damage to the joint cartilage that occurs throughout the entire joint tissue. This damage primarily manifests as pain in the affected area. In clinical practice, medication is commonly used to relieve pain, but the treatment's effectiveness is poor and recurrent attacks are likely. Schisandrin B is the most abundant biphenylcyclohexene lignan found in the traditional Chinese medicine Schisandra chinensis, and it possesses various pharmacological effects. This study aims to investigate the protective effect of Schisandrin B on mitochondrial damage in osteoarthritis (C28I2 cells) under an inflammatory environment induced by LPS. Cell proliferation and activity, scratch tests, and LDH release tests are utilized to assess cell growth and migration ability. The immunofluorescence assay was used to detect the expression levels of proliferation and apoptosis proteins. The Western Blot assay was used to detect the expression levels of mitochondrial fusion and division proteins. The JC-1 assay was used to detect changes in mitochondrial membrane potential. The mitochondrial fluorescence probe assay was used to detect mitochondrial activity. Through research, it was found that Schisandrin B promotes the proliferation, growth, and migration of C28I2 cells, reduces apoptosis of C28I2 cells, balances mitochondrial fusion and division, stabilizes mitochondrial membrane potential, and promotes mitochondrial activity in an LPS induced inflammatory environment.


Assuntos
Lignanas , Osteoartrite , Compostos Policíclicos , Humanos , Lipopolissacarídeos , Lignanas/farmacologia , Dor , Ciclo-Octanos
3.
Angew Chem Int Ed Engl ; 63(16): e202400952, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38372593

RESUMO

Cu-based catalysts have been identified as the most promising candidates for generation of C2+ products in electrochemical CO2 reduction reaction. Defect engineering in catalysts is a widely employed strategy for promoting C-C coupling on Cu. However, comprehensive understanding of defect structure-to-activity relationship has not been obtained. In this study, controllable defects generation is achieved, which leads to a series of Cu-based catalysts with various phase mixing degrees. It is observed that the Faradaic efficiency toward C2+ products increases with the phase mixing degree, reaching 81 % at maximum. In situ infrared absorption spectroscopy reveals that the catalysts with higher phase mixing degree tend to form *CO more easily and possess higher retention of *CO under high overpotential window, thereby promoting C-C coupling. This work sheds new light on the relationship between defects and C-C coupling, and the rational developed of more advanced Cu-base catalysts.

4.
Angew Chem Int Ed Engl ; 63(9): e202313858, 2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38185801

RESUMO

Catalysts involving post-transition metals have shown almost invincible performance on generating formate in electrochemical CO2 reduction reaction (CO2 RR). Conversely, Cu without post-transition metals has struggled to achieve comparable activity. In this study, a sulfur (S)-doped-copper (Cu)-based catalyst is developed, exhibiting excellent performance in formate generation with a maximum Faradaic efficiency of 92 % and a partial current density of 321 mA cm-2 . Ex situ structural elucidations reveal the presence of abundant grain boundaries and high retention of S-S bonds from the covellite phase during CO2 RR. Furthermore, thermodynamic calculations demonstrate that S-S bonds can moderate the binding energies with various intermediates, further improving the activity of the formate pathway. This work is significant in modifying a low-cost catalyst (Cu) with a non-metallic element (S) to achieve comparable performance to mainstream catalysts for formate generation in industrial grade.

5.
Am J Otolaryngol ; 44(4): 103897, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37094394

RESUMO

OBJECTIVE: To review the clinical characteristics and treatment outcomes of head and neck lymphatic malformations (HNLMs) in children. METHODS: A retrospective study of 91 patients with HNLMs was performed. RESULTS: The age ranged from 1 day to 14 years, of which 82.4 % (75/91) were under 2 years old and 45.1 % (41/91) were diagnosed at birth. The diagnostic rates of ultrasound, CT and MRI were 80.2 % (73/91), 90.1 % (82/91) and 100 % (8/8) respectively. There were 2 cases of complete excision, 8 of bleomycin sclerotherapy, and 81 of subtotal resection combined with bleomycin irrigation. Followed up for 3-93 months, all 91 cases were cured. CONCLUSIONS: HNLMs mostly occur within 2 years old, and nearly half of them are present at birth. Characteristic imaging findings can assist clinicians in diagnosis and treatment plan. Subtotal resection combined with bleomycin irrigation may be an appropriate first-line therapy for HNLMs involving the vital anatomical structures.


Assuntos
Cabeça , Anormalidades Linfáticas , Recém-Nascido , Humanos , Criança , Pré-Escolar , Estudos Retrospectivos , Pescoço , Bleomicina/uso terapêutico , Escleroterapia , Anormalidades Linfáticas/diagnóstico por imagem , Anormalidades Linfáticas/cirurgia , Resultado do Tratamento
6.
Eur Arch Otorhinolaryngol ; 280(7): 3287-3293, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-36757513

RESUMO

OBJECTIVE: To analyze the judgment efficiency of a computer stress model and severity score in severity evaluation and treatment plan selection of laryngomalacia patients. METHODS: Twenty-two children (12 cases in the operation group and 10 cases in the follow-up group) with moderate to severe laryngomalacia were assessed by laryngomalacia severity score (LSS) which included visual analogue scale (VAS) and clinical score. A computer stress model of the laryngeal cavity was constructed for all children, with the von Mises stress peak (VMSP) of the model used as another quantitative evaluation method. The ROC curves of two quantitative evaluation methods, the LSS and the VMSP, were analyzed respectively, according to the clinical guideline which is regarded as the gold standard for judging whether surgery is needed. The diagnostic efficiency indexes such as sensitivity, specificity, and accuracy were calculated. The area under ROC curves (AUC) of the two methods were compared by a DeLong model. Spearman correlation analysis and Kappa test were used to test the correlation and consistency of the two quantitative evaluation methods. The independent sample t test was used to compare the difference of LSS and VMSP between operation group and follow-up group. RESULTS: The sensitivity, specificity, and accuracy of LSS in judging whether laryngomalacia was operated or not were 83.33%, 80.00% and 81.82%, respectively, and the area under ROC curve (AUC) was 0.825 (p < 0.05). The sensitivity, specificity, and accuracy of the computer stress model for laryngomalacia were 58.33%, 90.00% and 72.73%, respectively, and the AUC was 0.796 (p < 0.05). The spearman correlation coefficient between LSS and VMSP was 0.833, p < 0.001, which is statistically significant. LSS (t = 3.251, p = 0.004) and VMSP (t = 2.435, p = 0.024) of the two groups were statistically different. CONCLUSION: VMSP and LSS have high diagnostic efficacy in the quantitative evaluation of the severity of laryngomalacia and the selection of treatment plan. The consistency of the two quantitative evaluation methods is good, which has practical value for the evaluation of the severity of laryngomalacia and has guiding significance for surgery.


Assuntos
Laringomalácia , Laringe , Criança , Humanos , Laringomalácia/complicações , Laringomalácia/diagnóstico , Laringomalácia/cirurgia , Curva ROC , Medição da Dor , Simulação por Computador , Estudos Retrospectivos
7.
Eur Arch Otorhinolaryngol ; 280(6): 2859-2864, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36609700

RESUMO

PURPOSE: To assess efficacy and prognostic factors of endoscopic balloon dilatation for the treatment of subglottic stenosis in children. METHODS: A retrospective review was performed on 49 pediatric patients with subglottic stenosis treated at the Shanghai Children's Hospital between December 2017 and December 2021. Specific demographic data, type and severity of the stenosis, number of balloon dilatations and outcomes were recorded and analyzed. RESULTS: Forty-nine children (30 male, 19 female) were included in the study with a median age at diagnosis of 24 (13-36.5) months, of which 7 (14.3%) had received open laryngotracheal reconstruction previously. The degree of subglottic stenosis was grade I in six patients, grade II in 16 patients, grade III in 20 patients and grade IV in seven patients. After various numbers of balloon dilatations (1-7 times), 29 patients showed a good outcome (decannulation or prevention of tracheostomy) and the success rate in that series was 59.2%. Overall, prognosis of balloon dilatation was not dependent on pathogeny (congenital or acquired) or open surgical history(P > 0.05), but rather on the severity grade of stenosis and the number of dilatations (P < 0.05). CONCLUSIONS: Endoscopic balloon dilatation can be safe and effective in the treatment of subglottic stenosis in children, except for more serious cases (grade IV). Open surgery should be considered if no significant improvement is observed after dilatation, especially after three or more dilatations.


Assuntos
Endoscopia , Laringoestenose , Criança , Humanos , Masculino , Feminino , Pré-Escolar , Constrição Patológica , China , Resultado do Tratamento , Estudos Retrospectivos , Laringoestenose/diagnóstico
8.
Eur Arch Otorhinolaryngol ; 280(1): 425-433, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36040517

RESUMO

OBJECTIVE: To investigate the clinical features and surgical outcomes of pediatric congenital first branchial cleft anomalies (CFBCAs). METHODS: We conducted a retrospective analysis of 100 children who were referred to Shanghai Children's Hospital from March 2014 to March 2022 for the treatment of CFBCAs. RESULTS: This study included 100 patients (33 males, 67 females) with an average age of 4.0 ± 2.7 years. 64 cases were type I FBCAs and 36 were type II. The main clinical manifestations included having a skin pit or discharge from it (62%), painless masses (5%), mucopurulent otorrhea (8%) and recurrent swelling with pain (90%) in the Pochet's triangle area. 92% had infection histories, 84% had incision and drainage histories, and 18% had surgical histories. 6 cases of tympanic membranous attachment were found by auricular endoscopy. Ultrasonography (US) was 55.6% (30/54) accurate and enhanced CT was 75% (75/100) accurate in diagnosing CFBCAs. We dissected the facial nerve (FN) in 46% cases. Lesions ended in the external auditory canal (EAC) wall in 86 cases. 69 exhibited close relationship with the parotid. The patients were followed up 0.25-8.2 years. 11 had postoperative temporary facial paralysis and all improved within 6 months. 3 had recurrence and they were secondarily successfully retreated. No EAC stenosis were found. CONCLUSIONS: CFBCAs often presented with repeated swelling and purulence in Pochet's triangle. CT, US and auricular endoscopy can assist in diagnosis and planning the surgical strategy. Complete excision in non-infection stage as soon as possible is the first choice for the treatment of CFBCAs.


Assuntos
Anormalidades Craniofaciais , Doenças Faríngeas , Masculino , Feminino , Criança , Humanos , Lactente , Pré-Escolar , Estudos Retrospectivos , China , Doenças Faríngeas/diagnóstico , Doenças Faríngeas/cirurgia , Anormalidades Craniofaciais/diagnóstico por imagem , Anormalidades Craniofaciais/cirurgia , Região Branquial/cirurgia , Região Branquial/anormalidades
9.
Am J Otolaryngol ; 43(6): 103610, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35988523

RESUMO

OBJECTIVES: To investigate the clinical characteristics of infantile subglottic hemangioma (SGH), and to observe the safety and efficacy of propranolol in the treatment of SGH. METHODS: The data of 21 children diagnosed with SGH and treated with propranolol in our hospital from March 2013 to January 2021 were retrospectively analyzed and followed up. RESULTS: Among the 21 cases, there were 7 males and 14 females. SGH was found 11 left-sided, 9 right-sided and 1 bilateral-sided. The clinical manifestations included stridor (13/21), respiratory distress (6/21), barking cough (5/21), feeding difficulty (4/21), three concave sign (4/21), cyanosis (2/21) and hoarseness (1/21). 8 patients had multiple cutaneous hemangiomas. The age of presentation ranged from 1 to 8 months, with a median of 1.1 months. 18 cases (85.7 %) had a history of misdiagnosis, 14 bronchitis/pneumonia, 5 laryngomalacia, 2 laryngeal obstruction and 1 asthma. The median ages at diagnosis were 3 months, with a range of 1.2-28 months. The treatment duration ranged from 6 to 25.6 months, with an average of (14.3 ± 4.9) months. Age at termination of treatment ranged from 9 to 38 months, with a median of 18.6 months, and only 2 cases were beyond 2 years old at that time. No adverse side effects from propranolol therapy occurred and all 21 cases were cured. CONCLUSIONS: We advocate a strong index of suspicion for SGH presenting with respiratory symptoms under 2 years old who has poor effect or repeated condition after routine treatment. Laryngoscopy combined with contrast-enhanced CT can confirm the diagnosis of SGH. Oral propranolol is safe and effective, and that early diagnosis and intervention of propranolol without further delay are crucial to the successful management. We advocate continue propranolol treatment beyond 18 months of age, furthermore, 2 years old may be the best time for therapy termination.


Assuntos
Hemangioma , Neoplasias Laríngeas , Masculino , Feminino , Criança , Humanos , Lactente , Pré-Escolar , Propranolol/uso terapêutico , Estudos Retrospectivos , Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/tratamento farmacológico , Hemangioma/diagnóstico , Hemangioma/tratamento farmacológico , Laringoscopia , Resultado do Tratamento , Administração Oral
10.
BMC Urol ; 20(1): 134, 2020 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-32859184

RESUMO

BACKGROUND: Primary small cell carcinoma of the bladder (SCCB) is a rare disease of the genitourinary tract and reported limitedly. SCCB is very aggressive and always mixed with other histologic components, but coexistence of SCCB and prostate adenocarcinoma is extremely rare. CASES PRESENTATION: Two aged males (72 and 58 years) were included in this study. Both of them presented with gross hematuria as initial symptom. Magnetic resonance imaging (MRI) demonstrated protruding lesions in the urinary bladder. Pathological examination after radical cystectomy and prostatectomy showed the concurrence of SCCB and prostate adenocarcinoma. One patient died of liver and lung metastasis 8 months after surgery, and the other patient was still alive after 19 months of follow-up. CONCLUSION: In this paper, we reported two unusual cases of coexistence of SCCB and prostate adenocarcinoma, and reviewed relative literatures with respect to the epidemiology, clinical features, pathologic features, diagnosis, treatment and prognosis of SCCB.


Assuntos
Adenocarcinoma/diagnóstico , Carcinoma de Células Pequenas/diagnóstico , Neoplasias Primárias Múltiplas/diagnóstico , Neoplasias da Próstata/diagnóstico , Neoplasias da Bexiga Urinária/diagnóstico , Idoso , Humanos , Masculino , Pessoa de Meia-Idade
11.
Environ Sci Technol ; 53(19): 11345-11352, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31452363

RESUMO

Particulate and vapor phase emissions in the diluted exhaust of a light-duty diesel engine designed for Euro 5 application have been sampled. The engine was operated in three modes, and samples were collected from the exhaust without aftertreatment but also with aftertreatment by an exhaust oxidation catalyst and particle filter. The samples were analyzed by two-dimensional gas chromatography with time-of-flight mass spectral detection. The results show overall removal efficiencies for the organic compound mass by the combination of oxidation catalyst and particle filter of 50, 56, and 74% for the high-speed/high-load, low-speed/low-load, and high-speed/low-load conditions respectively. The results are clearly indicative of substantial repartitioning of the particulate and vapor components within the abatement devices and show an apparently reduced efficiency for the removal of high-molecular-weight alkanes under high-speed/high-load conditions relative to lower-molecular-weight compounds, although this may be due to alkane formation by thermocracking of other species. A notable feature is the presence of oxygenated compounds in the emissions, which are not present in the fuel. These are increased under high-speed/high-load conditions, and the results suggest the formation in the aftertreatment devices as well as in the combustion process.


Assuntos
Poeira , Emissões de Veículos , Catálise , Gases , Oxirredução
12.
J Craniofac Surg ; 30(6): e553-e555, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30985347

RESUMO

OBJECTIVE: Lymphatic malformations (LMs) are rare and benign diseases. This article aimed to present a series of surgically treated giant cervicofacial LMs in children. METHODS: A retrospective analysis of giant cervicofacial LMs (tumor diameter greater than 10 cm) in children over the past 8 years was performed in our department. RESULTS: The 10 patients included 4 males and 6 females. Macrocystic lesion presented in 4 patients, mixed cystic lesion presented in 4 patients, and microcystic lesion presented in 2 patients. All the patients underwent surgical resection combined with bleomycin sclerotherapy. Despite the wide range of lesions, most patients (7/10, 70%) received only a single treatment, 3 patients had a recurrent lesion. Seven patients experienced complete or almost complete resolution of the disease with an average follow-up time of 26.4 months. CONCLUSIONS: Surgical resection is the preferred method for the treatment of giant LMs, combination of bleomycin sclerotherapy can reduce the recurrence rate. The curative effect of macrocystic disease is relatively enhanced compared with microcystic and mixed cystic diseases.


Assuntos
Linfangioma Cístico/terapia , Bleomicina/uso terapêutico , Pré-Escolar , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Escleroterapia/métodos , Resultado do Tratamento
13.
Eur Spine J ; 26(5): 1454-1462, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27388020

RESUMO

PURPOSES: To discuss whether radiologic parameters are closely related to posterior ligamentous complex (PLC) injury identified by magnetic resonance imaging (MRI). METHODS: One hundred and five thoracolumbar fracture (T11-L2) patients were retrospectively analyzed in the study. The patients were divided into different groups by the status of the PLC on MRI: intact, incompletely ruptured and ruptured. The radiographic parameters included the anterior edge-inferior endplate angle (AEIEA), the anterior edge displacement (AED), the Cobb angle (CA), the region angle (RA), the sagittal index (SI), local kyphosis (LK), the anterior/posterior vertebral height ratio (A/P ratio), the anterior vertebral height ratio (AVH ratio), and bony fragment in front of the fractured vertebra (BFOFV). T test, Pearson's Chi-square and multivariate logistic regression were calculated for the variables. RESULTS: Supraspinous ligament (SSL) rupture versus intact was not only associated with the occurrence of AEIEA <70°, LK >25° and BFOFV, but also with increased AED (9.89 ± 3.12 mm and 9.34 ± 3.36 mm, P = 0.034), RA (9.52 ± 3.93° versus 7.91 ± 3.99°, P = 0.042), and LK (23.98 ± 5.88° versus 15.55 ± 5.28°, P = 0.021). The indications for interspinous ligament (ISL) injury included AEIEA <75°, AEIEA <70° (P = 0.004 and P < 0.001, respectively), increased AED (P = 0.010), LK >25° (P = 0.024), AVH (P < 0.001), and BFOFV (P < 0.001). Multivariate logistic regression analysis revealed that AEIEA <70° and BFOFV were high risk factors for SSL rupture [standard partial regression coefficients (betas) were 0.439 and 0.408, P = 0.003 and 0.001, respectively] and ISL rupture (betas were 0.548 and 0.494, P = 0.028 and 0.001, respectively). Increased AED and LK >25° were also related to either ISL rupture (P = 0.035 and 0.001, respectively) or SSL rupture (P = 0.014 and 0.008, respectively). CONCLUSION: Our data may prove useful in a preliminary assessment of the PLC integrity based on plain radiographic imaging. We show that radiologic indications, such as AEIEA <70°, BFOFV, LK >25°, and increased AED, are correlated with ISL or SSL rupture, while RA, CA, SI, A/P ratio, and AVH ratio are not.


Assuntos
Ligamentos Longitudinais/diagnóstico por imagem , Ligamentos Longitudinais/lesões , Vértebras Lombares/diagnóstico por imagem , Fraturas da Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Adulto , Feminino , Humanos , Vértebras Lombares/lesões , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Vértebras Torácicas/lesões , Adulto Jovem
14.
Eur Spine J ; 26(1): 221-227, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27832363

RESUMO

PURPOSE: The aim of this study was to develop a novel method for observing the morphology of the blood vessels in the rabbit endplate. METHODS: Twenty 6-month-old rabbits were used in this study. The blood vessels in the L5 endplate in Group A were injected with iohexol and Group B with barium sulfate. Group C was the control group with saline. To optimize the study, Group B was divided into two subgroups: Group B-1 was injected with 100% (w/v) barium sulfate and Group B-2 with 50% (w/v). After injection, the L4-L5 vertebral body was excised and the cranial endplate of L5 was scanned using a micro-CT scanner. Models of the vertebral endplate and vessels were reconstructed using the 3D reconstruction software (Mimics 16.0) by calculating a bone threshold value, and then merged these two models to create a superimposed model. RESULTS: The 3D vessel models could not be created in Groups A and C, but they were clearly visualized in Group B. In the 3D model, the blood vessels extended from the subchondral bone to the endplate, and the density of the blood vessels in the area of the nucleus pulposus (NP) was higher than in the annulus fibrosus. CONCLUSIONS: The results of this study suggest that the blood vessels in the rabbit endplate can be clearly observed by the method described using barium sulfate [the 50% (w/v) gave better results compared with the 100% (w/v)]. The information from the 3D vessel structure could provide essential data to help us understand the nutrient pathways within the vertebral endplate.


Assuntos
Disco Intervertebral/irrigação sanguínea , Vértebras Lombares/irrigação sanguínea , Microtomografia por Raio-X , Animais , Meios de Contraste , Imageamento Tridimensional , Coelhos
15.
Faraday Discuss ; 189: 69-84, 2016 07 18.
Artigo em Inglês | MEDLINE | ID: mdl-27137954

RESUMO

A number of major research questions remain concerning the sources and properties of road traffic generated particulate matter. A full understanding of the composition of primary vehicle exhaust aerosol and its contribution to secondary organic aerosol (SOA) formation still remains elusive, and many uncertainties exist relating to the semi-volatile component of the particles. Semi-Volatile Organic Compounds (SVOCs) are compounds which partition directly between the gas and aerosol phases under ambient conditions. The SVOCs in engine exhaust are typically hydrocarbons in the C15-C35 range, and are largely uncharacterised because they are unresolved by traditional gas chromatography, forming a large hump in the chromatogram referred to as Unresolved Complex Mixture (UCM). In this study, thermal desorption coupled to comprehensive Two Dimensional Gas-Chromatography Time-of-Flight Mass-Spectrometry (TD-GC × GC-ToF-MS) was exploited to characterise and quantify the composition of SVOCs from the exhaust emission. Samples were collected from the exhaust of a diesel engine, sampling before and after a diesel oxidation catalyst (DOC), while testing at steady state conditions. Engine exhaust was diluted with air and collected using both filter and impaction (nano-MOUDI), to resolve total mass and size resolved mass respectively. Adsorption tubes were utilised to collect SVOCs in the gas phase and they were then analysed using thermal desorption, while particle size distribution was evaluated by sampling with a DMS500. The SVOCs were observed to contain predominantly n-alkanes, branched alkanes, alkyl-cycloalkanes, alkyl-benzenes, PAHs and various cyclic aromatics. Particle phase compounds identified were similar to those observed in engine lubricants, while vapour phase constituents were similar to those measured in fuels. Preliminary results are presented illustrating differences in the particle size distribution and SVOCs composition when collecting samples with and without a DOC. The results indicate that the DOC tested is of very limited efficiency, under the studied engine operating conditions, for removal of SVOCs, especially at the upper end of the molecular weight range.

16.
Pathol Int ; 66(9): 506-10, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27478038

RESUMO

The expression of EphA4 has been well documented in the development of nerve and in certain types of human cancer. Few studies of EphA4, however, have focused on breast carcinoma. In this study, a set of breast carcinomas was subjected to immunohistochemical staining. In normal luminal cells, EphA4 was weakly detected in 11 (14.3 %), moderately detected in 15 (19.5 %) and highly detected in 51 out of 77 (66.2 %) samples, while in breast carcinoma cells, EphA4 was weakly detected in 42 (54.5 %), moderately detected in 19 (24.7 %) and highly detected in 16 out of 77 (20.8 %) samples (P < 0.001). The expression of EphA4 protein was significantly reduced in 68.8 % of breast carcinoma samples comparing with normal cells. The expression of EphA4 was significantly associated with tumor grade (P = 0.003), TNM stage (P = 0.034), lymph node metastasis (P = 0.034) and Ki-67 (P < 0.001). No significant relationship was found between the expression of EphA4 and age, molecular subtypes, and HER2 status. Survival analysis showed that significant association of low expression of EphA4 in tumor cells with short overall survival (P = 0.048) and disease-free survival (P = 0.051). Our data show that EphA4 was reduced in breast carcinoma, which is associated with high grade, advanced TNM stage, lymph node metastasis, and poor outcome of patients.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Receptor EphA4/biossíntese , Adulto , Idoso , Neoplasias da Mama/mortalidade , Carcinoma Ductal de Mama/mortalidade , Intervalo Livre de Doença , Feminino , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metástase Linfática , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Receptor EphA4/análise
17.
Eur Spine J ; 25(6): 1661-4, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26831537

RESUMO

PURPOSE: To describe and illustrate a modified technique for using translaminar screw in the cervicothoracic junction (C7-T2). METHODS: 12 patients (8 males and 4 females, average age was 52 years) underwent insertion of unilateral or bilateral translaminar screws by using our modified technique. With this modified technique, a tiny unicortical "hole" was made at the middle of the contralateral lamina, and the screw can be directly visualized through the unicortical "hole" to prevent violating the spinal canal. RESULTS: With this modified technique, the mean operation time was 205 min (range 145-360) and mean estimated blood loss was 445 ml (range 260-1250). The mean length of the laminar screws was 27 (range 24-30) mm. The results of the 12 patients with an average follow-up of 17 (6-33) months demonstrated this modified technique to be safe and effective in the fixation of cervicothoracic junction. CONCLUSION: In this modified technique, a tiny unicortical "hole" which was made at the middle of the dorsal lamina of cervicothoracic junction (C7-T2). By directly visualizing the screw inserting against the dorsal cortices of the lamina, this modified technique can reduce the risk of violation of the spinal canal and shorten the operation time.


Assuntos
Parafusos Ósseos , Vértebras Cervicais/cirurgia , Fusão Vertebral , Vértebras Torácicas/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Duração da Cirurgia , Fusão Vertebral/instrumentação , Fusão Vertebral/métodos
18.
Eur Spine J ; 25(12): 4199-4207, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-27554355

RESUMO

PURPOSE: To evaluate the feasibility of cortical bone trajectory (CBT) screws fixation via pedicle or pedicle rib unit in the cadaveric thoracic spine (T9-T12). METHODS: Computed tomography (CT) images of 100 patients are analyzed by multiplanar reconstruction. Ten cadaveric thoracic spines are used to insert 4.5 × 35.0 mm CBT screws at all levels from T9 to T12. RESULTS: Maximal screw length obtained by CT has a tendency to gradually increase from T9 (29.64 mm) to T12 (32.84 mm), and the difference reaches significant level at all levels except T9 versus T10 (P < 0.01). Maximal screw diameter increases from T9 (4.92 mm) to T12 (7.47 mm) and the difference reaches significant level among all levels (P < 0.01). Lateral angle increases from T9 (7.37°) to T12 (10.47°), and the difference reaches significant level among all levels except T11 versus T12. Cephalad angle from T9 to T12 are 19.03°, 22.10°, 25.62° and 27.50° (P < 0.01), respectively. The percentage of the inner and outer pedicle breakage are 2.5 and 22.5 %, respectively. The violation of lateral pedicle wall occurs at T9 and T10, especially for women at T9. CONCLUSIONS: Both radiographic and cadaveric studies establish the feasibility of CBT screws placement via pedicle or pedicle rib unit in the lower thoracic spine (T9-T12). Furthermore, our measurements are also useful for application of this technique.


Assuntos
Osso Cortical/diagnóstico por imagem , Procedimentos Ortopédicos/métodos , Parafusos Pediculares , Vértebras Torácicas/cirurgia , Adulto , Idoso , Cadáver , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Vértebras Torácicas/diagnóstico por imagem , Tomografia Computadorizada por Raios X
19.
Eur Spine J ; 24(8): 1711-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25784595

RESUMO

PURPOSE: A new in vivo rabbit model was developed to investigate the effects of shear force on intervertebral disc (IVD). METHODS: Japanese white rabbits (n = 38) were used for this study. The L4/5 discs in Group A (n = 10) were subjected to a constant shear force (50 N) using a custom-made external loading device for 1 month; in Group B (n = 10) for 2 months; whereas in Group C (n = 10), loading device was attached to the spine but the discs remained unloaded. Group D (n = 8) was a non-operated intact control group. After loading, the loading devices were taken out and the animals were given X-ray and MRI examination. After X-ray and MRI examination, the animals were euthanized for histological analysis. RESULTS: After 1 and 2 months of loading, radiographic findings showed significant disc height narrowing in L4/5 discs of the animals in loading groups, and slight lumbar spondylolisthesis in some animals of Group B. MRI showed a significant decrease in nucleus pulposus (NP) area and signal intensity from T2-weighted images. Histologically, loss of normal NP cells and disorganization of the architecture of the annulus occurred, and proteoglycan stain decreased. CONCLUSIONS: The results of this study suggest that disc degeneration can be induced by hyper-physiological shear loading in the rabbit IVD. Long-term shear loading may result in structural disc failure inducing lumbar spondylolisthesis and progressive disc degeneration, which, however, has to be proven by further studies.


Assuntos
Degeneração do Disco Intervertebral/etiologia , Disco Intervertebral/patologia , Vértebras Lombares/patologia , Estresse Mecânico , Animais , Feminino , Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/patologia , Vértebras Lombares/diagnóstico por imagem , Imageamento por Ressonância Magnética , Coelhos , Radiografia , Distribuição Aleatória , Espondilolistese/diagnóstico por imagem , Espondilolistese/etiologia , Suporte de Carga
20.
J Craniofac Surg ; 25(4): 1470-2, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24448534

RESUMO

One patient of neurofibromatosis type I originating from the pterygopalatine fossa and salivary gland underwent surgery in our department. At the outset, the case was misdiagnosed as arising from salivary gland tumors, and surgery was immediately performed. The tumor was entered directly, which induced ferocious bleeding. The subsequent hemostasis with tamponade and compression caused intracranial venous sinus thrombosis, which induced irreversible intracranial complications and finally resulted in death. The experience regarding the diagnosis and treatment of the case was retrospectively reviewed and shared in this article.


Assuntos
Neurofibromatose 1/cirurgia , Fossa Pterigopalatina/cirurgia , Neoplasias das Glândulas Salivares/cirurgia , Perda Sanguínea Cirúrgica/fisiopatologia , Erros de Diagnóstico , Evolução Fatal , Hemorragia/etiologia , Hemostasia Cirúrgica , Humanos , Complicações Intraoperatórias/etiologia , Masculino , Erros Médicos , Neurofibromatose 1/diagnóstico , Neurofibromatose 1/diagnóstico por imagem , Fossa Pterigopalatina/diagnóstico por imagem , Neoplasias das Glândulas Salivares/diagnóstico , Neoplasias das Glândulas Salivares/diagnóstico por imagem , Trombose dos Seios Intracranianos/etiologia , Tomografia Computadorizada por Raios X , Adulto Jovem
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