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1.
Phys Chem Chem Phys ; 22(12): 6528-6537, 2020 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-32091071

RESUMO

α-Pinene, the most abundant monoterpene in the atmosphere, accounts for more than 50% of global monoterpene emission. Though its reaction with ozone has been generally perceived as a major source of secondary organic aerosols (SOAs), direct evidence of its reaction intermediates (RI) and their evolution remain lacking. Here we study the ozonolysis of α-pinene between 180 and 298 K using a long-path, temperature-variable aerosol cooling chamber coupled to a rapid-scan time-resolved Fourier transform infrared spectrometer. The spectroscopic signatures of large Criegee intermediates (CIs) and hydroperoxides (HPs) were found for the first time. The aerosol size evolution during the reaction was also measured. In contrast to a previous perception, we show that temperature plays a determinant role in the ozonolysis kinetics. Finally, we show that the formation of HPs is an energetically favorable pathway to dissipate CIs. This study provides new insights into the ozonolysis of α-pinene and its contribution to SOA formation.

2.
J Clin Lab Anal ; 34(2): e23065, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31617251

RESUMO

BACKGROUND: Inflammation is a necessary component of chronic kidney disease (CKD) that can be attributed to an accumulation of toxins and a reduced clearance of proinflammatory cytokines. Procalcitonin (PCT) is a widely applied biomarker in the diagnosis of infection, and considering the presence of pre-existing inflammation in CKD patients, the PCT level could be high in such a population; however, no reference value for PCT in CKD patients has been available to date. METHODS: During the present study period, 361 CKD patients and 119 healthy controls were included. The PCT level and other biochemistry parameters were assayed by using a COBAS system. Statistical analysis was conducted to compare the differences in PCT levels and other biochemistry parameters between the two groups, and linear regression was used to assess the correlation between two variables. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the performance of PCT and the optimal cutoff value to differentiate between CKD patients and healthy controls. RESULTS: The PCT level in CKD patients was significantly higher than that in healthy controls, and among the CKD patients, the PCT level was increased with advanced clinical stage. Moreover, PCT was moderately correlated with CysC. The optimal off-value was 0.075 with a sensitivity of 94.7% and specificity of 90.8%. CONCLUSION: The PCT level was significantly higher in CKD patients than in healthy controls, and the reference value for CKD patients should be adjusted to avoid unnecessary antibiotic treatments which may pose a negative impact on residual renal function.

3.
Environ Pollut ; 257: 113498, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31761579

RESUMO

Carbamazepine (CBZ), a widely detected pharmaceutical in wastewaters, cannot currently be treated by conventional activated sludge technologies, as it is highly resistant to biodegradation. In this study, the degradation kinetics and reaction mechanisms of CBZ by hydroxyl radical (OH) and sulfate radical ()-based advanced oxidation processes (AOPs) were investigated with a combined experimental/theoretical approach. We first measured the UV absorption spectrum of CBZ and compared it to the theoretical spectrum. The agreement of two spectra reveals an extended π-conjugation system on CBZ molecular structure. The second-order rate constants of OH and with CBZ, measured by competition kinetics method, were (4.63 ±â€¯0.01) × 109 M-1 s-1 and (8.27 ±â€¯0.01) × 108 M-1 s-1, respectively at pH 3. The energetics of the initial steps of CBZ reaction with OH and were also calculated by density functional theory (DFT) at SMD/M05-2X/6-311++G**//M05-2X/6-31 + G**level. Our results reveal that radical addition is the dominant pathway for both OH and . Further, compared to the positive ΔGR0 value for the single electron transfer (SET) reaction pathway between CBZ and OH, the ΔGR0 value for SET reaction between CBZ and is negative, showing that this reaction route is thermodynamically favorable. Our results demonstrated the remarkable advantages of AOPs for the removal of refractory organic contaminants during wastewater treatment processes. The elucidation of the pathways for the reaction of OH and with CBZ are beneficial to predict byproducts formation and assess associated ecotoxicity, providing an evaluation mean for the feasibility of AOPs application.

4.
Int J Endocrinol ; 2019: 3078012, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31737068

RESUMO

For the rare but aggressive insular thyroid carcinoma (ITC), there's no clear evidence to determine whether prophylactic central compartment neck dissection (CCND) is necessary for cN0 disease. This study provides the first evidence that treating cN0 ITC without prophylactic CCND is associated with decreased survival regardless of T staging and administration of RAI therapy. Background. Regarding the rare but aggressive insular thyroid carcinoma (ITC), the value of prophylactic central compartment neck dissection (CCND) for clinically node-negative (cN0) disease is unclear. We aimed to provide the first evidence. Methods. N0 and pN1a ITC patients were identified from the Surveillance, Epidemiology, and End Results database. These patients were divided into thyroid-surgery + CCND group (pN0/pN1a patients confirmed by CCND) and thyroid-surgery group (cN0 patients without CCND). Differences in overall survival (OS) and disease-specific survival (DSS) between the two groups were evaluated. Subgroup analyses were also conducted. Results. Of the overall 112 patients, 44 (39.3%) received CCND. On multivariate analyses, the lobectomy ± isthmusectomy/total-thyroidectomy (Lob/TT) group demonstrated poorer OS and DSS than the Lob/TT + CCND group (P < 0.05). When we separately analyzed patients treated by TT, multivariate analyses showed the TT group still revealed compromised OS and DSS than the TT + CCND group (P < 0.05). Furthermore, absence of CCND independently predicted decreased OS no matter whether radioactive iodine (RAI) was administered. Similar results were obtained for T3/T4 patients. Moreover, for T1/T2 patients receiving CCND, 0/12 died during the study period, while for T1/T2 patients without CCND, 8/23 (34.8%) died, 5/23 (21.7%) due to ITC. Conclusion. Regardless of T staging and RAI treatment, cN0-ITC patients without CCND had decreased survival compared with pN0/pN1a patients receiving CCND. Therefore, if a cN0 patient is diagnosed with ITC, prophylactic CCND may be considered as a secondary procedure (postoperatively diagnosed) or a primary procedure (preoperatively/intraoperatively diagnosed). Prospective studies are expected to validate the conclusion.

5.
Eur J Surg Oncol ; 45(11): 2143-2150, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31253544

RESUMO

BACKGROUND: We aimed to explore whether the anatomic extent of lymph node metastases (AE-LNM) could independently predict prognosis of node-positive major salivary gland carcinoma (MaSGC). METHODS: A total of 376 pathologically node-positive MaSGC patients were identified from the Surveillance, Epidemiology and End Results database and constituted the training cohort. Using the X-Tile program, these patients were divided into three groups based on AE-LNM degrees. Discrimination of overall survival (OS) and disease-specific survival (DSS) was evaluated and compared with the 8th American Joint Committee on Cancer (AJCC) pN classification. The results were externally validated by 220 patients in a Chinese multicenter cohort (Validation cohort). RESULTS: Using the training cohort, AE-LNM was divided into Extent 1 (spread to parotid LNs or level I), Extent 2 (spread to level II-IV) and Extent 3 (spread to level V or bilateral LNs or rare LNs). Regarding both OS and DSS, the AE-LNM model revealed clear separation of survival curves, while the pN classification failed to discriminate the prognosis of pN1 and pN2 patients. When we incorporated both the AE-LNM model and AJCC pN classification into the same multivariate Cox analyses, AE-LNM was still an independent prognostic factor, while the AJCC pN classification lost its significance. These results were externally validated by the validation cohort. CONCLUSION: AE-LNM is an independent nodal prognosticator for node-positive MaSGC and may have improved discriminative ability over the current AJCC pN classification. Integration of anatomic extent of LNM into the current AJCC N classification could be considered.

6.
COPD ; 16(2): 160-167, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-31094228

RESUMO

Acute exacerbation (AE) is the main cause of increased disability and mortality for patients with Chronic Obstructive Pulmonary Disease (COPD). Short-term re-exacerbation after discharge is common for in-hospital patients with AECOPD. Thus, we aimed to design a scoring system to effectively predict the 30-day re-exacerbation using simple and easily accessible variables. We retrospectively enrolled 686 cases hospitalized for AECOPD in two Chinese hospitals from 2005 to 2017. A variety of parameters were collected like demographics, clinical manifestations and treatments in stable and AE period. The optimal subset of covariates in the multivariate logistic analysis was identified by the smallest Akaike Information Criterion (AIC) and was further used to develop a practical and reliable nomogram to predict the 30-day re-exacerbation. The efficacy of the nomogram was internally validated by concordance index (C-index) and a calibration plot. The incidence of 30-day re-exacerbation was 15.8%. Based on the smallest AIC, eight easily-accessible parameters were included in the nomogram, including sex, COPD assessment test (CAT) scores, AE with respiratory failure in the previous year, new purulent sputum, new cardiovascular events, combined antibiotic therapy, theophylline therapy for AE and ICU admission. Our nomogram revealed good discriminative ability with the C-index of 0.702. The calibration curve showed good agreement between nomogram-predicted probability and actual observation. Incorporating eight common variables, a nomogram for 30-day re-exacerbation after discharge with high predictive performance was constructed for patients with AECOPD, which was helpful in predicting individualized risk of re-exacerbation and offering individualized post-discharge support.

7.
Artigo em Inglês | MEDLINE | ID: mdl-30655663

RESUMO

Background: COPD, characterized by chronic inflammation and airway remodeling, has significant pathological alterations in composition and deposition of the extracellular matrix. The expression of procollagen 1 C-terminal peptide (PICP) and collagen type 1 C-terminal telopeptide (ICTP), two major by-products in the synthesis and degradation of collagen, was shown to be positively correlated with inflammatory mediator levels in previous studies. Purpose: In this study, we investigated whether the serum concentrations of PICP and ICTP were associated with the inflammation level for patients with stable COPD. Patients and methods: We collected serum samples from 25 control subjects and 20 patients with stable COPD from December 2011 to October 2012 in Shanghai Zhongshan Hospital and Shanghai Dahua Hospital. We determined concentrations of PICP, ICTP, C-reactive protein (CRP), IL-6, IL-8, and tumor necrosis factor (TNF)-α by using enzyme-linked immunosorbent assay methods. Results: Demographic characteristics were comparable between the two groups. In patients with stable COPD, serum levels of CRP, IL-6, IL-8, and TNF-α were all elevated compared to control subjects, but only changes of IL-6 achieved statistical significance. Serum concentration of PICP was significantly elevated in patients with COPD, and level of ICTP was slightly decreased. Moreover, serum concentrations of PICP were positively correlated with the levels of both IL-6 and IL-8. Conclusion: The increased levels of serum PICP in COPD might indicate the condition of airway remodeling, and IL-6 and/or IL-8 might play an important role in stimulating collagen synthesis.


Assuntos
Colágeno Tipo I/sangue , Mediadores da Inflamação/sangue , Interleucina-6/sangue , Interleucina-8/sangue , Fragmentos de Peptídeos/sangue , Peptídeos/sangue , Pró-Colágeno/sangue , Doença Pulmonar Obstrutiva Crônica/sangue , Idoso , Remodelação das Vias Aéreas , Biomarcadores/sangue , Estudos de Casos e Controles , China , Feminino , Volume Expiratório Forçado , Humanos , Pulmão/metabolismo , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Índice de Gravidade de Doença , Regulação para Cima , Capacidade Vital
8.
Int J Chron Obstruct Pulmon Dis ; 13: 3733-3747, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30532529

RESUMO

Purpose: By reanalyzing the gene expression profile GSE76925 in the Gene Expression Omnibus database using bioinformatic methods, we attempted to identify novel candidate genes promoting the development of emphysema in patients with COPD. Patients and methods: According to the Quantitative CT data in GSE76925, patients were divided into mild emphysema group (%LAA-950<20%, n=12) and severe emphysema group (%LAA-950>50%, n=11). Differentially expressed genes (DEGs) were identified using Agilent GeneSpring GX v11.5 (corrected P-value <0.05 and |Fold Change|>1.3). Known driver genes of COPD were acquired by mining literatures and retrieving databases. Direct protein-protein interaction network (PPi) of DEGs and known driver genes was constructed by STRING.org to screen the DEGs directly interacting with driver genes. In addition, we used STRING.org to obtain the first-layer proteins interacting with DEGs' products and constructed the indirect PPi of these interaction proteins. By merging the indirect PPi with driver genes' PPi using Cytoscape v3.6.1, we attempted to discover potential pathways promoting emphysema's development. Results: All the patients had COPD with severe airflow limitation (age=62±8, FEV1%=28±12). A total of 57 DEGs (including 12 pseudogenes) and 135 known driving genes were identified. Direct PPi suggested that GPR65, GNB4, P2RY13, NPSR1, BCR, BAG4, and IMPDH2 were potential pathogenic genes. GPR65 could regulate the response of immune cells to the acidic microenvironment, and NPSR1's expression on eosinophils was associated with asthma's severity and IgE level. Indirect merging PPi demonstrated that the interacting network of TP53, IL8, CCR2, HSPA1A, ELANE, PIK3CA was associated with the development of emphysema. IL8, ELANE, and PIK3CA were molecules involved in the pathological mechanisms of emphysema, which also in return proved the role of TP53 in emphysema. Conclusion: Candidate genes such as GPR65, NPSR1, and TP53 may be involved in the progression of emphysema.


Assuntos
Biologia Computacional , Redes Reguladoras de Genes , Enfisema Pulmonar/genética , Idoso , Bases de Dados Genéticas , Progressão da Doença , Feminino , Volume Expiratório Forçado , Perfilação da Expressão Gênica/métodos , Estudos de Associação Genética , Marcadores Genéticos , Predisposição Genética para Doença , Humanos , Pulmão/diagnóstico por imagem , Pulmão/fisiopatologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Prognóstico , Enfisema Pulmonar/diagnóstico por imagem , Enfisema Pulmonar/fisiopatologia , Receptores Acoplados a Proteínas-G/genética , Índice de Gravidade de Doença , Tomografia Computadorizada por Raios X , Transcriptoma , Proteína Supressora de Tumor p53/genética
9.
Ann Surg Oncol ; 25(8): 2316-2322, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29845406

RESUMO

BACKGROUND: The prognostic value of central lymph node (CLN) status in papillary thyroid cancer (PTC) remains controversial. This study aimed to provide the first evidence on this issue for the aggressive tall-cell variant (TCV) subtype. METHODS: The study identified TCV patients from the Surveillance, Epidemiology, and End Results database. The Kaplan-Meier method, log-rank test, and multivariate Cox regression models were used for analysis. RESULTS: Of the 744 patients included, 404 were recorded as N0, which were pathologically or only clinically confirmed. Overall survival (OS) and cancer-specific survival (CSS) did not differ significantly between the N0 and pN1a patients (p > 0.05). To investigate the reason, the N0 patients were subdivided according to the number of examined lymph nodes (ELN). The patients with a N0 diagnosis confirmed by two or more ELNs (N0-e2+) showed significantly better outcomes than the pN1a patients and their N0 counterparts without ELN (N0-e0) (p < 0.05), whereas the N0-e0 and pN1a groups demonstrated comparable outcomes in both the log-rank and multivariate analyses (p > 0.05). Moreover, the subgroup analyses showed that even among the patients with early T-staging (T1-T2) or receipt of radioactive iodine (RAI) therapy, the N0-e0 patients still demonstrated compromised OS compared with the N0-e2+ group (p < 0.05). CONCLUSION: The cN0 patients without ELN (N0-e0) had outcomes similar to those of the pN1a patients, but showed a poorer OS than the N0-e2+ group regardless of T-staging and RAI administration, suggesting that occult CLN metastases might act as a negative prognosticator in cN0 TCV. Therefore, prophylactic central neck dissection might be considered for biopsy-proven cN0 TCV patients. Prospective studies are expected to further validate our conclusions.


Assuntos
Carcinoma Papilar/secundário , Radioisótopos do Iodo/uso terapêutico , Linfonodos/patologia , Radioterapia Adjuvante/mortalidade , Neoplasias da Glândula Tireoide/patologia , Tireoidectomia/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Papilar/radioterapia , Carcinoma Papilar/cirurgia , Terapia Combinada , Feminino , Seguimentos , Humanos , Linfonodos/efeitos da radiação , Linfonodos/cirurgia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida , Neoplasias da Glândula Tireoide/radioterapia , Neoplasias da Glândula Tireoide/cirurgia , Adulto Jovem
10.
Water Res ; 137: 233-241, 2018 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-29550726

RESUMO

Hydroxyl radical (•OH) based advanced oxidation technologies (AOTs) are effective for removing non‒steroidal anti-inflammatory drugs (NSAIDs) during water treatment. In this study, we systematically investigated the degradation kinetics of naproxen (NAP), a representative NSAID, with a combination of experimental and theoretical approaches. The second-order rate constant (k) of •OH oxidation of NAP was measured to be (4.32 ±â€¯0.04) × 109 M-1 s-1, which was in a reasonable agreement with transition state theory calculated k value (1.08 × 109 M-1 s-1) at SMD/M05-2X/6-311++G**//M05-2X/6-31+G** level of theory. The calculated result revealed that the dominant reaction intermediate is 2‒(5‒hydroxy‒6‒methoxynaphthalen‒2‒yl)propanoic acid (HMNPA) formed via radical adduct formation pathway, in which •OH addition onto the ortho site of the methoxy-substituted benzene ring is the most favorable pathway for the NAP oxidation. We further investigated the subsequent •OH oxidation of HMNPA via a kinetic modelling technique. The k value of the reaction of HMNPA and •OH was determined to be 2.22 × 109 M-1 s-1, exhibiting a similar reactivity to the parent NAP. This is the first study on the kinetic and mechanistic aspects of NAP and its reaction intermediates. The current results are valuable in future study evaluating and extending the application of •OH based AOTs to degrade NAP and other NSAIDs of concern in water treatment plants.


Assuntos
Anti-Inflamatórios não Esteroides/química , Radical Hidroxila/química , Naproxeno/química , Cinética , Oxirredução , Propionatos/química , Eliminação de Resíduos Líquidos/métodos
11.
Phys Chem Chem Phys ; 19(42): 28641-28646, 2017 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-29058008

RESUMO

1,8-Dihydroxynaphthalene-2,7-dicarbaldehyde (DHDA) has been strategically designed and synthesized with the aim to study the competitive multiple hydrogen bonding (H-bonding) effect and the associated excited-state intramolecular proton transfer reaction (ESIPT). In nonpolar solvents such as cyclohexane, equilibrium exists between the two H-bonding isomers DHDA-23_OO and DHDA-23_OI, both of which possess double intramolecular H-bonds. In polar, aprotic solvents such as CH2Cl2, DHDA-23_OO becomes the predominant species. Due to various degrees of H-bond induced changes of electronic configuration each isomer reveals a distinct absorption feature and excited-state behavior, in which DHDA-23_OI in cyclohexane undergoes double ESIPT in a stepwise manner, giving the first and second proton-transfer tautomer emissions maximized at ∼500 nm and 660 nm, respectively. As for DHDA-23_OO both single and double ESIPT are prohibited, resulting in an intense normal 450 nm emission band. In a single crystal DHDA-23_OI is the dominant species, which undergoes excited state double proton transfer, giving intense emission bands at 530 nm and 650 nm. The mechanism associated with competitive multiple H-bonding energetics and ESIPT was underpinned by detailed spectroscopy/dynamics and computational approaches.

12.
Cell Biol Int ; 41(12): 1391-1398, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28782906

RESUMO

Dental pulp stem cells (DPSCs) have been proposed as a promising source of stem cells in nerve regeneration due to their close embryonic origin and ease of harvest. Resveratrol (RSV) is a natural polyphenolic and possesses many biological functions such as anti-inflammatory activity and protection against atherosclerosis and neuroprotective activities. There is increasing evidence showing that RSV plays a pivotal role in neuron protection and neuronal differentiation. In this study, we isolated DPSCs from impacted third molars and investigated whether RSV induces neuronal differentiation of DPSCs. To avoid loss of DPSCs multipotency, all the experiments were conducted on cells at early passages. RT-PCR results showed that RSV-treated DPSCs (RSV-DPSCs) significantly increased the expression of the neuroprogenitor marker Nestin. When RSV-DPSCs were differentiated with neuronal induction media (RSV-dDPSCs), they showed a cell morphology similar to neurons. The expression of neuronal-specific marker genes Nestin, Musashi, and NF-M in RSV-dDPSCs was significantly increased. Immunocytochemical staining and Western blot analysis showed that the expression of neuronal marker proteins, Nestin, and NF-M, was significantly increased in RSV-dDPSCs. Therefore, we have shown that RSV treatment, along with the use of neuronal induction media, effectively promotes neuronal cell differentiation of DPSCs.


Assuntos
Células-Tronco Adultas/citologia , Células-Tronco Adultas/efeitos dos fármacos , Polpa Dentária/citologia , Polpa Dentária/efeitos dos fármacos , Neurônios/citologia , Neurônios/efeitos dos fármacos , Estilbenos/farmacologia , Células-Tronco Adultas/metabolismo , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Polpa Dentária/metabolismo , Polpa Dentária/fisiologia , Células Epiteliais/citologia , Humanos , Neurônios/metabolismo , Resveratrol
13.
Phys Chem Chem Phys ; 19(23): 15454-15462, 2017 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-28580968

RESUMO

Collision-induced dissociation (CID) of sodiated glucose was investigated using electronic structure calculations and resonance excitation in a low-pressure linear ion trap. The major dissociation channels in addition to desodiation are dehydration and C2H4O2 elimination reactions which the barrier heights are near to or lower than the sodiation energy of glucose. Dehydration reaction involves the transfer of the H atom from the O2 atom to the O1 atom, followed by the cleavage of the C1-O1 bond. Notably, α-glucose has a dehydration barrier lower than that of ß-glucose. This difference results in the larger branching ratio of dehydration reactions involving α-glucose, which provides a simple and fast method for identifying the anomeric configurations of glucose. The C2H4O2 elimination starts from the H atom transfer from the O1 atom to the O0 atom, followed by the cleavage of the C1-O0 bond. These results were further confirmed by experimental study using 18O-isotope-labeled compounds. Both the experimental data and theoretical calculations suggest that the dehydration reaction and cross-ring dissociation of sodiated carbohydrates mainly occur at the reducing end during low-energy CID.

14.
Oncotarget ; 8(18): 29722-29740, 2017 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-28430613

RESUMO

BACKGROUND: Neck dissection for laryngeal squamous cell carcinoma (LSCC) patients could provide complementary prognostic information for AJCC N staging, like lymph node ratio (LNR). The aim of this study was to develop effective nomograms to better predict survival for LSCC patients treated with neck dissection. RESULTS: 2752 patients were identified and randomly divided into training (n = 2477) and validation (n = 275) cohorts. The 3- and 5-year probabilities of cancer-specific mortality (CSM) were 30.1% and 37.2% while 3- and 5-year death resulting from other causes (DROC) rate were 6.2% and 11.3%, respectively. 13 significant prognostic factors including LNR for overall (OS) and 12 (except race) for CSS were enrolled in the nomograms. Concordance index as a commonly used indicator of predictive performance, showed the nomograms had superiority over the no-LNR models and TNM classification (Training-cohort: OS: 0.713 vs 0.703 vs 0.667, CSS: 0.725 vs 0.713 vs 0.688; Validation-cohort: OS: 0.704 vs 0.690 vs 0.658, cancer-specific survival (CSS): 0.709 vs 0.693 vs 0.672). All calibration plots revealed good agreement between nomogram prediction and actual survival. MATERIALS AND METHODS: We identified LSCC patients undergoing neck dissection diagnosed between 1988 and 2008 from Surveillance, Epidemiology, and End Results (SEER) database. Optimal cutoff points were determined by X-tile program. Cumulative incidence function was used to analyze cancer-specific mortality (CSM) and death resulting from other causes (DROC). Significant predictive factors were used to establish nomograms estimating overall (OS) and cancer-specific survival (CSS). The nomograms were bootstrapped validated both internally and externally. CONCLUSIONS: Comprehensive nomograms were constructed to predict OS and CSS for LSCC patients treated with neck dissection more accurately.


Assuntos
Carcinoma de Células Escamosas/mortalidade , Neoplasias Laríngeas/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/cirurgia , Causas de Morte , Feminino , Humanos , Incidência , Neoplasias Laríngeas/diagnóstico , Neoplasias Laríngeas/epidemiologia , Neoplasias Laríngeas/cirurgia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Nomogramas , Reprodutibilidade dos Testes , Programa de SEER , Taxa de Sobrevida , Resultado do Tratamento , Carga Tumoral , Adulto Jovem
15.
Oncotarget ; 8(17): 28526-28543, 2017 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-28415710

RESUMO

BACKGROUND: The relationship between marital status and oral cavity squamous cell carcinoma (OCSCC) survival has not been explored. The objective of our study was to evaluate the impact of marital status on OCSCC survival and investigate the potential mechanisms. RESULTS: Married patients had better 5-year cancer-specific survival (CSS) (66.7% vs 54.9%) and 5-year overall survival (OS) (56.0% vs 41.1%). In multivariate Cox regression models, unmarried patients also showed higher mortality risk for both CSS (Hazard Ratio [HR]: 1.260, 95% confidence interval (CI): 1.187-1.339, P < 0.001) and OS (HR: 1.328, 95% CI: 1.266-1.392, P < 0.001). Multivariate logistic regression showed married patients were more likely to be diagnosed at earlier stage (P < 0.001) and receive surgery (P < 0.001). Married patients still demonstrated better prognosis in the 1:1 matched group analysis (CSS: 62.9% vs 60.8%, OS: 52.3% vs 46.5%). MATERIALS AND METHODS: 11022 eligible OCSCC patients were identified from Surveillance, Epidemiology, and End Results (SEER) database, including 5902 married and 5120 unmarried individuals. Kaplan-Meier analysis, Log-rank test and Cox proportional hazards regression model were used to analyze survival and mortality risk. Influence of marital status on stage, age at diagnosis and selection of treatment was determined by binomial and multinomial logistic regression. Propensity score matching method was adopted to perform a 1:1 matched cohort. CONCLUSIONS: Marriage has an independently protective effect on OCSCC survival. Earlier diagnosis and more sufficient treatment are possible explanations. Besides, even after 1:1 matching, survival advantage of married group still exists, indicating that spousal support from other aspects may also play an important role.


Assuntos
Carcinoma de Células Escamosas/epidemiologia , Estado Civil , Neoplasias Bucais/epidemiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/terapia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/mortalidade , Neoplasias Bucais/patologia , Neoplasias Bucais/terapia , Gradação de Tumores , Metástase Neoplásica , Estadiamento de Neoplasias , Razão de Chances , Vigilância da População , Programa de SEER , Taxa de Sobrevida , Adulto Jovem
16.
J Mass Spectrom ; 51(12): 1180-1186, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27677117

RESUMO

Electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) mainly generate protonated ions from peptides and proteins but sodiated (or potassiated) ions from carbohydrates. The ion intensities of sodiated (or potassiated) carbohydrates generated by ESI and MALDI are generally lower than those of protonated peptides and proteins. Ab initio calculations and transition state theory were used to investigate the reasons for the low detection sensitivity for underivatized carbohydrates. We used glucose and cellobiose as examples and showed that the low detection sensitivity is partly attributable to the following factors. First, glucose exhibits a low proton affinity. Most protons generated by ESI or MALDI attach to water clusters and matrix molecules. Second, protonated glucose and cellobiose can easily undergo dehydration reactions. Third, the sodiation affinities of glucose and cellobiose are small. Some sodiated glucose and cellobiose dissociate into the sodium cations and neutral carbohydrates during ESI or MALDI process. The increase of detection sensitivity of carbohydrates in mass spectrometry by various methods can be rationalized according to these factors. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Carboidratos/análise , Carboidratos/química , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Cátions , Limite de Detecção
17.
Huan Jing Ke Xue ; 37(12): 4570-4576, 2016 Dec 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965296

RESUMO

It was well known that physiological indices of submerged macrophytes could reflect change of water quality. The correlation between physiological indices of submerged macrophytes and change of water quality was studied under the cooperation of in-situ monitoring and lab analysis, combined with measuring Chlorophyll and free proline (PRO) contents as well as peroxidase (POD) activities in the leaves of Potamogeton wrightii Morong and Potamogeton crispus L. under different water quality and nutrition status. The results showed: ①there were significant spatial differences among water factors and the comprehensive eutrophication index (TLI) of distribution areas of Potamogeton wrightii Morong and Potamogeton crispus L. Mesotrophic water was more suitable for the growth of Potamogeton wrightii Morong, while Potamogeton crispus L. grew well in eutrophic water. ②there were significant spatial differences among physiological indices of Potamogeton wrightii Morong and Potamogeton crispus L. in Taihu Lake. Besides, there were significant relationships between Chlorophyll contents, POD activities of two species and TLI. ③water transparency as well as nitrogen and phosphorus nutrition were important factors leading to changes in Chlorophyll contents and POD activities of Potamogeton wrightii Morong and Potamogeton crispus L.. The findings from this study indicate that physiological properties of Potamogeton wrightii Morong and Potamogeton crispus L. have a very close correlation with nutrition status and physiochemical properties of water.


Assuntos
Lagos , Potamogetonaceae/crescimento & desenvolvimento , Qualidade da Água , China , Clorofila , Eutrofização , Nitrogênio , Peroxidases , Fósforo
18.
J Phys Chem B ; 120(8): 1780-7, 2016 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-26651834

RESUMO

High-level correlated electronic structure calculation and dual-level variational transition state theory with multidimensional tunneling calculation for rate constants have been performed on four noble gas exchange reactions [(1) He + HNBHe'(+) → He' + HNBHe(+), (2) He + HNBNe(+) → Ne + HNBHe(+), (3) Ne + HNBNe'(+) → Ne' + HNBNe(+), and (4) Ar + HNBAr'(+) → Ar' + HNBAr(+)] and on three (3)He isotopic analogues (He + HNB(3)He(+), (3)He + HNBHe(+), and (3)He + HNB(3)He(+)) of the first reaction. The classical barrier heights were predicted to be 8.9, 6.8, 5.7, and 5.5 kcal/mol for the four reactions, respectively. The tunneling effects were found to be important below 250 K for the He reactions and below 150 K for the Ne and Ar reactions. Kinetic helium isotope effects as large as 7.8 at 100 K were predicted for the (3)He + HNB(3)He(+) reaction. Additionally, the structures and energies of the Kr + HNBKr'(+) and Xe + HNBXe'(+) systems have also been studied.

19.
Environ Sci Technol ; 49(22): 13322-30, 2015 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-26477990

RESUMO

The ubiquitous presence of cyclic volatile methylsiloxanes (cVMS) in the global atmosphere has recently raised environmental concern. In order to assess the persistence and long-range transport potential of cVMS, their second-order rate constants (k) for reactions with hydroxyl radical ((•)OH) in the gas phase are needed. We experimentally and theoretically investigated the kinetics and mechanism of (•)OH oxidation of a series of cVMS, hexamethylcyclotrisiloxane (D3), octamethycyclotetrasiloxane (D4), and decamethycyclopentasiloxane (D5). Experimentally, we measured k values for D3, D4, and D5 with (•)OH in a gas-phase reaction chamber. The Arrhenius activation energies for these reactions in the temperature range from 313 to 353 K were small (-2.92 to 0.79 kcal·mol(-1)), indicating a weak temperature dependence. We also calculated the thermodynamic and kinetic behaviors for reactions at the M06-2X/6-311++G**//M06-2X/6-31+G** level of theory over a wider temperature range of 238-358 K that encompasses temperatures in the troposphere. The calculated Arrhenius activation energies range from -2.71 to -1.64 kcal·mol(-1), also exhibiting weak temperature dependence. The measured k values were approximately an order of magnitude higher than the theoretical values but have the same trend with increasing size of the siloxane ring. The calculated energy barriers for H-atom abstraction at different positions were similar, which provides theoretical support for extrapolating k for other cyclic siloxanes from the number of abstractable hydrogens.


Assuntos
Poluentes Atmosféricos/química , Siloxanas/química , Atmosfera , Gases/química , Hidrogênio/química , Radical Hidroxila/química , Cinética , Modelos Químicos , Oxirredução , Temperatura , Termodinâmica
20.
J Am Chem Soc ; 137(45): 14349-57, 2015 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-26493857

RESUMO

1,8-Dihydroxy-2-naphthaldehyde (DHNA), having doubly intramolecular hydrogen bonds, was strategically designed and synthesized in an aim to probe a long-standing fundamental issue regarding synchronous versus asynchronous double-proton transfer in the excited state. In cyclohexane, DHNA shows the lowest lying S0 →S1 (π-π*) absorption at ∼400 nm. Upon excitation, two large Stokes shifted emission bands maximized at 520 and 650 nm are resolved, which are ascribed to the tautomer emission resulting from the first and second proton-transfer products, denoted by TA* and TB*, respectively. The first proton transfer (DHNA* → TA*) is ultrafast (< system response of 150 fs), whereas the second proton transfer is reversible, for which the rates of forward (TA* → TB*) and backward (TA* ← TB*) proton transfer were determined to be (1.7 ps)(-1) and (3.6 ps)(-1), respectively. The fast equilibrium leads to identical population lifetimes of ∼54 ps for both TA* and TB* tautomers. Similar excited-state double-proton transfer takes place for DHNA in a single crystal, resulting in TA* (560 nm) and TB* (650 nm) dual-tautomer emission. A comprehensive 2D plot of reaction potential energy surface further proves that the sequential two-step proton motion is along the minimum energetic pathway firmly supporting the experimental results. Using DHNA as a paradigm, we thus demonstrate unambiguously a stepwise, proton-relay type of intramolecular double-proton transfer reaction in the excited state, which should gain fundamental understanding of the multiple proton transfer reactions.

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