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1.
Appl Opt ; 61(35): 10390-10399, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36607097

RESUMO

The intelligent reflecting surface (IRS) and angle diversity receiver (ADR) jointly assisted indoor visible light communication (VLC) system is proposed to improve average signal-to-noise ratio (ASNR) performance. Specifically, to maximize the ASNR at the receiving plane, the roll angle and yaw angle of IRS and the inclination angle of the side detector in the ADR structure are optimized simultaneously as one non-convex problem. With the bat algorithm, the optimal solution is numerically obtained. Results show that when the transmit power of the light emitting diode lamp array is 1 W, the ASNRs of this VLC system optimized by IRS and ADR are approximately 7.89 dB, 3.58 dB, and 2.09 dB higher than those of the original, IRS-assisted, and ADR-assisted VLC systems, respectively. Furthermore, the transmission rate and bit error rate performances of the original, IRS-assisted, ADR-assisted, and IRS and ADR jointly assisted indoor VLC systems are also simulated and compared; it is found that the performance improvement of the indoor VLC system jointly optimized by IRS and ADR is more evident than that of the other three VLC systems. This study will benefit the research and development of indoor VLC systems.

2.
Sensors (Basel) ; 22(18)2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36146231

RESUMO

Maneuvering target imaging based on inverse synthetic aperture radar (ISAR) imaging has recently drawn significant attention. Among the many autofocusing technologies which are crucial in ISAR imaging, minimum-entropy-based autofocusing (MEA) is highly robust. However, traditional MEA is not suitable for terahertz (THz) ISAR imaging. For one thing, the iterative process in traditional MEA is too complicated to be utilized for THz-ISAR imaging with tremendous data. For another, THz wavelengths are very short and extremely sensitive to phase errors, so the compensation accuracy of the traditional MEA method can hardly meet the requirements of THz radar high-resolution imaging. Therefore, in this paper, the MEA algorithm based on the damped Newton method is proposed, which improves computational efficiency by approximating the first- and second-order partial derivatives of the image entropy function with respect to the phase errors, as well as by the fast Fourier transform (FFT). The search step size factor is introduced to ensure that the algorithm can converge along the declination direction of the entropy function and obtain the globally optimal ISAR image. The experimental results validated the efficiency of the proposed algorithm, which is promising in THz-ISAR imaging of maneuvering targets.

3.
Int J Mol Sci ; 23(10)2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35628638

RESUMO

Polylactic acid-glycolic acid (PLGA) has been widely used in bone tissue engineering due to its favorable biocompatibility and adjustable biodegradation. 3D printing technology can prepare scaffolds with rich structure and function, and is one of the best methods to obtain scaffolds for bone tissue repair. This review systematically summarizes the research progress of 3D-printed, PLGA-based scaffolds. The properties of the modified components of scaffolds are introduced in detail. The influence of structure and printing method change in printing process is analyzed. The advantages and disadvantages of their applications are illustrated by several examples. Finally, we briefly discuss the limitations and future development direction of current 3D-printed, PLGA-based materials for bone tissue repair.


Assuntos
Engenharia Tecidual , Alicerces Teciduais , Osso e Ossos , Glicolatos , Poliésteres , Impressão Tridimensional , Engenharia Tecidual/métodos , Alicerces Teciduais/química
4.
J Environ Sci (China) ; 100: 328-339, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33279046

RESUMO

Amides, a series of significant atmospheric nitrogen-containing volatile organic compounds (VOCs), can participate in new particle formation (NPF) throught interacting with sulfuric acid (SA) and organic acids. In this study, we investigated the molecular interactions of formamide (FA), acetamide (AA), N-methylformamide (MF), propanamide (PA), N-methylacetamide (MA), and N,N-dimethylformamide (DMF) with SA, acetic acid (HAC), propanoic acid (PAC), oxalic acid (OA), and malonic acid (MOA). Global minimum of clusters were obtained through the association of the artificial bee colony (ABC) algorithm and density functional theory (DFT) calculations. The conformational analysis, thermochemical analysis, frequency analysis, and topological analysis were conducted to determine the interactions of hydrogen-bonded molecular clusters. The heterodimers formed a hepta or octa membered ring through four different types of hydrogen bonds, and the strength of the bonds are ranked in the following order: SOH•••O > COH•••O > NH•••O > CH•••O. We also evaluated the stability of the clusters and found that the stabilization effect of amides with SA is weaker than that of amines with SA but stronger than that of ammonia (NH3) with SA in the dimer formation of nucleation process. Additionally, the nucleation capacity of SA with amides is greater than that of organic acids with amides.


Assuntos
Amidas , Hidrogênio , Ligação de Hidrogênio , Modelos Teóricos , Ácidos Sulfúricos
5.
Int J Mol Sci ; 20(7)2019 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-30934774

RESUMO

Polychlorinated phenoxathiins (PCPTs), polychlorinated dibenzothiophenes (PCDTs), and polychlorinated thianthrenes (PCTAs) are sulfur analogues of polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/DFs). Chlorothiophenols (CTPs) and chlorophenols (CPs) are key precursors for the formation of PCTA/PT/DTs, which can react with H or OH to form chloro(thio)phenoxy radical, sulfydryl/hydroxyl-substituted phenyl radicals, and (thio)phenoxyl diradicals. However, previous radical/radical PCTA/DT formation mechanisms in the literature failed to explain the higher concentration of PCDTs than that of PCTAs under the pyrolysis or combustion conditions. In this work, a detailed thermodynamics and kinetic calculations were carried out to investigate the pre-intermediate formation for PCTA/PT/DTs from radical/molecule coupling of the 2-C(T)P with their key radical species. Our study showed that the radical/molecule coupling mechanism explains the gas-phase formation of PCTA/PT/DTs in both thermodynamic and kinetic perspectives. The S/C coupling modes to form thioether-(thio)enol intermediates are preferable over the O/C coupling modes to form ether-(thio)enol intermediates. Thus, although the radical/molecule coupling of chlorophenoxy radical with 2-C(T)P has no effect on the PCDD/PT formation, the radical/molecule coupling of chlorothiophenoxy radical with 2-C(T)P plays an important role in the PCTA/PT formation. Most importantly, the pre-PCDT intermediates formation pathways from the couplings of sulfydryl/hydroxyl-substituted phenyl radical with 2-C(T)P and (thio)phenoxyl diradicals with 2-C(T)P are more favorable than pre-PCTA/PT intermediates formation pathways from the coupling of chlorothiophenoxy radical with 2-C(T)P, which provides reasonable explanation for the high PCDT-to-PCTA ratio in the environment.


Assuntos
Clorofenóis/química , Dibenzofuranos/química , Compostos Heterocíclicos/química , Teoria Quântica , Tiofenos/química , Radicais Livres/química , Cinética , Conformação Molecular
6.
Int J Mol Sci ; 20(11)2019 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-31141990

RESUMO

Chlorothiophenols (CTPs) are known to be key and direct precursors of polychlorinated thianthrene/dibenzothiophenes (PCTA/DTs). Self/cross-coupling of the chlorothiophenoxy radicals (CTPRs), sulfydryl-substituted phenyl radicals and thiophenoxyl diradicals evolving from CTPs are initial and important steps for PCTA/DT formation. In this study, quantum chemical calculations were carried out to investigate the homogenous gas-phase formation of PCTA/DTs from self/cross-coupling of 2,4-dichlorothiophenoxy radical (R1), 2-sulfydryl-3,5-dichlorophenyl radical (R2) and 3,5-dichlorothiophenoxyl diradical (DR) at the MPWB1K/6-311+G(3df,2p)//MPWB1K/6-31+G(d,p) level. The rate constants of crucial elementary steps were deduced over 600-1200 K, using canonical variational transition state theory with a small curvature tunneling contribution. For the formation of PCTAs, the S•/σ-C• condensation with both thiophenolic sulfur in one radical and ortho carbon in the other radical bonded to single electron is the most efficient sulfur-carbon coupling mode, and the ranking of the PCTA formation potential is DR + DR > R2 + DR > R1 + DR > R1 + R2 > R1 + R1. For the formation of PCDTs, the σ-C•/σ-C• coupling with both ortho carbon in the two radicals bonded to single electron is the energetically favored carbon-carbon coupling mode, and the ranking of the PCDT formation potential is: R2 + DR > R2 + R2 > R1 + DR > R1 + R2 > R1 + R1. The PCTA/DTs could be produced from R1, R2 and DR much more readily than PCDD/DFs from corresponding oxygen substituted radicals.


Assuntos
Compostos Heterocíclicos/síntese química , Compostos de Sulfidrila/síntese química , Tiofenos/síntese química , Simulação por Computador , Cinética
7.
Med Sci Monit ; 23: 984-993, 2017 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-28231233

RESUMO

BACKGROUND Mutations of DNA topoisomerase II (TOP2A) are associated with chemotherapy resistance, whereas dual-specificity phosphatase 6 (DUSP6) negatively regulates members of the mitogen-activated protein (MAP) kinase superfamily to control cell proliferation. This study assessed TOP2A and DUSP6 single nucleotide polymorphisms (SNPs) in non-small cell lung cancer (NSCLC) patients for association with chemoradiotherapy responses and prognosis. MATERIAL AND METHODS A total of 140 Chinese patients with histologically confirmed NSCLC were enrolled and subjected to genotyping of TOP2A rs471692 and DUSP6 rs2279574 using Taqman PCR. An independent sample t test was used to analyze differences in tumor regression after radiotherapy versus SNP risk factors. Kaplan-Meier curves analyzed overall survival, followed by the log-rank test and Cox proportional hazard models. RESULTS There were no significant associations of TOP2A rs471692 and DUSP6 rs2279574 polymorphisms or clinicopathological variables with response to chemoradiotherapy (p>0.05). Comparing overall survival of 87 patients with stage I-III NSCLC treated with radiotherapy or chemoradiotherapy to clinicopathological variables, the data showed that tumor regression, weight loss, clinical stage, and cigarette smoking were independent prognostic predictors (p=0.009, 0.043, 0.004, and 0.025, respectively). Tumor regression rate >0.34 was associated with patent survival versus tumor regression rate ≤0.34 (p=0.007). CONCLUSIONS TOP2A rs471692 and DUSP6 rs2279574 SNPs were not associated with chemoradiotherapy response, whereas tumor regression, weight loss, clinical stage, and cigarette smoking were independent prognostic predictors for these Chinese patients with NSCLC.


Assuntos
Antígenos de Neoplasias/genética , Carcinoma Pulmonar de Células não Pequenas/enzimologia , Carcinoma Pulmonar de Células não Pequenas/radioterapia , DNA Topoisomerases Tipo II/genética , Proteínas de Ligação a DNA/genética , Fosfatase 6 de Especificidade Dupla/genética , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/metabolismo , Povo Asiático/genética , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/patologia , Quimiorradioterapia , China , DNA Topoisomerases Tipo II/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fosfatase 6 de Especificidade Dupla/metabolismo , Etnicidade/genética , Feminino , Humanos , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Mutação , Polimorfismo de Nucleotídeo Único , Prognóstico , Resultado do Tratamento
8.
Ecotoxicol Environ Saf ; 145: 569-574, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28800532

RESUMO

Accumulating evidence demonstrates that the aberrant expression of cell cycle regulation and DNA repair genes can result in abnormal cell proliferation and genomic instability in eukaryotic cells under different stresses. Herein, Arabidopsis thaliana (Arabidopsis) seedlings were grown hydroponically on 0.5 × MS media containing cadmium (Cd) at 0-2.5mgL-1 for 5d of treatment. Real time quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis revealed that expression of DNA damage repair and cell cycle regulation genes, including BRCA1, MRE11, WEE1, CDKA;1 and PCNA1, showed an inverted U-shaped dose-response. In contrast, notably reduced expression was observed for G1-to-S transition-related genes, Histone H4, E2Fa and PCNA2; DSB end processing, GR1; G2-to-M transition-related gene, CYCB1;1; and DNA mismatch repair, MSH2, MSH6 and MLH1 genes in root tips exposed to 0.125-2.5mg/L Cd for 5d. Flow cytometry (FCM) analysis revealed significant increases of cells with a 2C nuclear content and with a 4C and 8C nuclear content under Cd stresses of 0.125 and 1-2.5mgL-1, respectively. Our results suggest that 0.125mgL-1 Cd-induced DNA damage induced the marked G1/S arrest, leading to accelerated growth in root tips, while 1.0-2.5mgL-1 Cd-induced DNA damage caused a notable G2/M arrest in root tips, leading to reduced growth in root tips. This may be a protective mechanism that prevents cells with damaged DNA from dividing under Cd stress.


Assuntos
Arabidopsis/efeitos dos fármacos , Cádmio/toxicidade , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Dano ao DNA , Meristema/efeitos dos fármacos , Poluentes do Solo/toxicidade , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Pontos de Checagem do Ciclo Celular/genética , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Instabilidade Genômica/efeitos dos fármacos , Meristema/genética , Plântula/efeitos dos fármacos , Plântula/genética
9.
Toxicol Mech Methods ; 27(2): 121-127, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27894210

RESUMO

Benzo(a)pyrene (BaP) was a well-known environmental pollutant, numerous studies had implicated BaP as a causative agent in human cancer, particularly lung cancer. The lemongrass essential oil (LEO) possessed various pharmacological activities, especially the anti-oxidative stress and cancer prevention. In the current study, human embryonic lung fibroblast (HELF) cells were treated with 25 mM BaP in the absence or presence of 0.5%, 1% or 2.5% LEO and the cell viability and levels of oxidative stress (OS) and DNA damage in the cells were then measured. Nineteen chemical constituents were identified in LEO, with citral being the main component, representing about 68.78%. LEO was able to protect the HELF cells against BaP-induced loss in cell viability, achieving a maximum of 95.58% cell viability at the 0.5% concentration. Treatment of HELF cells with BaP alone significantly increased the level of Malondialdehyde (MDA) and decreased superoxide dismutase (SOD) and catalase (CAT). However, these effects were suppressed when the cells were also treated with LEO, leading to enhanced levels of SOD and CAT activities (2.9- and 2-fold, respectively, compared with BaP treatment only) and reduced the level of MDA in the cells (43% reduction in malondialdehyde level). At the same time, LEO also reduced the level of DNA damage, as shown by a reduced level of 8-hydroxy-deoxyguanosine (8-OHdG). Taken together, the results showed that LEO offered protection against BaP-induced OS and DNA damage, suggesting that LEO could be a promising agent for lung cancer chemoprevention.


Assuntos
Benzo(a)pireno/toxicidade , Dano ao DNA/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Óleos Voláteis/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Óleos de Plantas/farmacologia , Terpenos/farmacologia , Técnicas de Cultura de Células , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fibroblastos/metabolismo , Humanos , Pulmão/citologia , Pulmão/embriologia , Estresse Oxidativo/genética
10.
Clin Lab ; 62(3): 301-10, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27156317

RESUMO

BACKGROUND: Dual-specificity phosphatase 6 (DUSP6) inactivates different target kinases to regulate cell proliferation and differentiation. Altered DUSP6 expressions or gene polymorphisms are associated with human cancer development including non-small cell lung cancer (NSCLC). DNA topoisomerase II alpha (TOP2A) regulates chromosome condensation and chromatid separation, and altered TOP2A expressions are associated with drug resistance development. This study assessed DUSP6 and TOP2A single nucleotide polymorphisms (SNPs) associated with NSCLC patient survival. METHODS: This study included 152 surgically resected NSCLC patients and 277 chemoradiotherapy treated inoperable cases. DNA samples from each patient were genotyped for DUSP6 and TOP2A SNPs. Kaplan-Meier survival analysis, log-rank test, and Cox proportional hazard model were used to evaluate the association between these variants and NSCLC overall survival. RESULTS: DUSP6 rs2279574 A/A genotype was associated with significantly poor inoperable NSCLC patient overall survival (A/A vs. C/C, adjusted HR = 1.549, 95% CI = 1.019-2.355). Stratification analysis against clinical stage, histology, weight loss, and ECOG performance status revealed that the DUSP6 rs2279574 A/A variant homozygous genotype is associated with a decrease in survival of stage IV NSCLC patients compared to those with the C/C genotype (log-rank, p = 0.003). No association was found among histology, weight loss, and ECOG performance status. Moreover, there was no association of TOP2A SNPs between clinicopathological and survival data. CONCLUSIONS: Data obtained from the current study demonstrated that functional DUSP6 rs2279574 polymorphism was able to predict inoperable NSCLC patient survival after chemoradiotherapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/terapia , Quimiorradioterapia , Fosfatase 6 de Especificidade Dupla/genética , Neoplasias Pulmonares/terapia , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Prognóstico , Modelos de Riscos Proporcionais
11.
Clin Lab ; 61(7): 699-708, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26299068

RESUMO

BACKGROUND: To investigate the prognostic factors of Nasopharyngeal Carcinoma (NPC). METHODS: Retrospective analysis was carried out on the clinical data collected from three hospitals in North China between September, 1999 to March, 2012. RESULTS: Higher survival rates (1, 3, 5, and 10 year) were found in NPC patients who were female, non-smokers, early clinical phase, and T1-2 (p < 0.05). No association was found between survival rates and drinking habits, lesion location, pathological types, N stages, and radiotherapy pattern. The 1-, 3-, and 5-year overall survival rates were equal following both conventional radiotherapy and Intensity-Modulating Radiotherapy (IMRT). CONCLUSIONS: Patient gender, age, smoking status, clinical stages, and T stages all served as prognostic factors of nasopharyngeal carcinoma.


Assuntos
Neoplasias Nasofaríngeas/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Carcinoma , Criança , China/epidemiologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/mortalidade , Neoplasias Nasofaríngeas/patologia , Neoplasias Nasofaríngeas/terapia , Estadiamento de Neoplasias , Procedimentos Cirúrgicos Otorrinolaringológicos , Modelos de Riscos Proporcionais , Fatores de Proteção , Radioterapia de Intensidade Modulada , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Fatores Sexuais , Fumar/efeitos adversos , Fumar/mortalidade , Taxa de Sobrevida , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
12.
Tumour Biol ; 35(9): 9201-10, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24929326

RESUMO

This meta-analysis of published cohort studies was conducted to evaluate whether promoter methylation of the secreted frizzled-related protein 1 (SFRP1) gene contributes to colorectal carcinogenesis. The Web of Science (1945 ~ 2013), the Cochrane Library Database (Issue 12, 2013), PubMed (1966 ~ 2013), EMBASE (1980 ~ 2013), CINAHL (1982 ~ 2013), and the Chinese Biomedical Database (CBM) (1982 ~ 2013) were searched without language restrictions. Meta-analysis was conducted using the STATA 12.0 software. We calculated odds ratio (OR) and its 95 % confidence interval (95 % CI) to estimate the correlations between SFRP1 promoter methylation and colorectal carcinogenesis. In the present meta-analysis, 8 cohort studies with a total of 942 patients with colorectal cancer (CRC) were included. The pooled results revealed that the frequency of SFRP1 promoter methylation in cancer tissues were significantly higher than those of normal, adjacent, and benign tissues (cancer tissues vs. normal tissues: OR = 31.49, 95 % CI = 17.57 ~ 56.44, P < 0.001; cancer tissues vs. adjacent tissues: OR = 5.95, 95 % CI 3.12 ~ 10.00, P < 0.001; cancer tissues vs. benign tissues: OR = 3.01, 95 % CI 1.72 ~ 5.27, P < 0.001; respectively). Furthermore, ethnicity-stratified analysis indicated that SFRP1 promoter methylation was strongly correlated with colorectal carcinogenesis among both Asians and Caucasians (all P < 0.05). Our findings provide empirical evidence that SFRP1 promoter methylation may be correlated with the pathogenesis of CRC.


Assuntos
Carcinogênese/genética , Neoplasias Colorretais/genética , Metilação de DNA , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas de Membrana/genética , Regiões Promotoras Genéticas/genética , Povo Asiático/genética , Neoplasias Colorretais/etnologia , Humanos , Razão de Chances , População Branca/genética
13.
Tumour Biol ; 35(9): 9411-8, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24952889

RESUMO

Our study aims to discuss the association between inflammation-related factors such as single nucleotide polymorphisms (SNPs) with susceptibility and recurrence in nasopharyngeal carcinoma. We used Taqman real-time polymerase chain reaction (PCR) to characterize the genetic variation of five SNPs in 194 nasopharyngeal carcinoma patients and 231 healthy subjects. All statistical analysis is performed with statistical product and service solutions v13.0; odds ratio (OR) value and 95 % confidence interval (CI) were calculated. There is no relationship between TGFß1 -869 T/C, IL-6 -634C/G, TGFß1 -509C/T, IL1 -511C/T and nasopharyngeal carcinoma susceptibility. Both single factor and multiple factors analysis showed that IL1a -889 T/T genotype is significantly associated with nasopharyngeal carcinoma in decreasing the risk of nasopharyngeal carcinoma. A highly significant association was found between IL1a -889 T/T genotype and protective genotype as defined by various pathological types. This is more obvious in the protective genotype of the non-keratin-type squamous carcinoma undifferentiated type. We also discovered that genotype G/G and C/G + G/G of IL6 -634 gene are associated with reduced recurrence of nasopharyngeal carcinoma. IL1a -889 gene polymorphism and susceptibility is related to nasopharyngeal carcinoma and can potentially decrease the risk of nasopharyngeal carcinoma in the Han Chinese population in north China. IL1-889 TT genotype is protective genotype for nasopharyngeal carcinoma. We have provided evidence that the GG genotype of the IL6 -634 gene is associated with recurrent risk of nasopharyngeal carcinoma. The G allele is the protective gene of nasopharyngeal carcinoma recurrence.


Assuntos
Predisposição Genética para Doença/genética , Inflamação/genética , Neoplasias Nasofaríngeas/genética , Polimorfismo de Nucleotídeo Único , Adolescente , Adulto , Idoso , Povo Asiático/genética , China , Feminino , Frequência do Gene , Predisposição Genética para Doença/etnologia , Genótipo , Humanos , Interleucina-1alfa/genética , Interleucina-6/genética , Desequilíbrio de Ligação , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Neoplasias Nasofaríngeas/etnologia , Reação em Cadeia da Polimerase , Fatores de Risco , Adulto Jovem
14.
Mol Biol Rep ; 41(8): 4929-40, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24718782

RESUMO

The current meta-analysis of case-control studies was conducted to evaluated the relationships of genetic polymorphisms in the CYP1A1 and CYP1B1 genes with the susceptibility to bladder cancer, aiming at determine whether these polymorphisms may contribute to the pathogenesis of bladder cancer. Related articles were determined via searching the following electronic databases without any language restrictions: PubMed, CISCOM, CINAHL, Web of Science, Google Scholar, EBSCO, Cochrane Library, and CBM databases for relevant articles published before November 1st, 2013. STATA 12.0 software was also selected to deal with statistical data. The relationships were evaluated using the pooled odds ratios (ORs) and their 95% confidence intervals (CI). Eleven case-control studies with a total of 2,609 bladder cancer patients and 2,634 healthy subjects met the inclusion criteria. The results of our meta-analysis demonstrated that CYP1A1 genetic polymorphisms were associated with increased risks of bladder cancer (allele model: RR = 1.18, 95% CI 1.07-1.30, P = 0.001; dominant model: RR = 1.15, 95% CI 1.05-1.27, P = 0.003; respectively), especially among 11599G>C, 2455A>G, 3810T>C, and 113T>C polymorphisms. A subgroup analysis by ethnicity was conducted to investigate its effect on susceptibility to bladder cancer. The subgroup analysis results revealed positive significant correlations between CYP1A1 genetic polymorphisms and bladder cancer risk among Asians (allele model: RR = 1.26, 95% CI 1.10-1.44, P = 0.001; dominant model: RR = 1.22, 95% CI 1.08-1.38, P = 0.001), but not among Caucasians (all P < 0.05). Nevertheless, we observed no significant correlations between CYP1B1 genetic polymorphisms and bladder cancer risk (all P > 0.05). Our meta-analysis indicates that CYP1A1 genetic polymorphisms may be involved in the pathogenesis of bladder cancer, especially among 11599G>C, 2455A>G, 3810T>C, and 113T>C polymorphisms. However, CYP1B1 genetic polymorphisms may not be important determinants of bladder cancer susceptibility.

15.
Nat Commun ; 14(1): 1246, 2023 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-36870994

RESUMO

The adoption of electric vehicles (EVs) on a large scale is crucial for meeting the desired climate commitments, where affordability plays a vital role. However, the expected surge in prices of lithium, cobalt, nickel, and manganese, four critical materials in EV batteries, could hinder EV uptake. To explore these impacts in the context of China, the world's largest EV market, we expand and enrich an integrated assessment model. We find that under a high material cost surge scenario, EVs would account for 35% (2030) and 51% (2060) of the total number of vehicles in China, significantly lower than 49% (2030) and 67% (2060) share in the base-line, leading to a 28% increase in cumulative carbon emissions (2020-2060) from road transportation. While material recycling and technical battery innovation are effective long-term countermeasures, securing the supply chains of critical materials through international cooperation is highly recommended, given geopolitical and environmental fragilities.

16.
Pathol Oncol Res ; 28: 1610751, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36590386

RESUMO

About 70% of non-small cell lung cancer (NSCLC) patients require radiotherapy. However, due to the difference in radiation sensitivity, the treatment outcome may differ for the same pathology and choice of treatment. Poly (ADP-ribose) polymerase 1 (PARP-1) is a key gene responsible for DNA repair and is involved in base excision repair as well as repair of single strand break induced by ionizing radiation and oxidative damage. In order to investigate the relationship between PARP-1 gene polymorphism and radiation sensitivity in NSCLC, we collected 141 primary NSCLC patients undergoing three-dimensional conformal radiotherapy. For each case, the gross tumor volumes (GTV) before radiation and that after 40 Gy radiation were measured to calculate the tumor regression rate. TaqMan real-time polymerase chain reaction was performed to genotype the single-nucleotide polymorphisms (SNPs). Genotype frequencies for PARP-1 genotypes were 14.2% for C/C, 44.7% for C/G and 41.1% for G/G. The average tumor regression rate after 40 Gy radiation therapy was 35.1% ± 0.192. Tumor regression rate of mid-term RT of C/C genotype was 44.6% ± 0.170, which was higher than that of genotype C/G and G/G (32.4% ± 0.196 and 34.8% ± 0.188, respectively) with statistical significance (F = 3.169 p = 0.045). The higher tumor regression rate in patients with C/C genotype suggested that G allele was a protective factor against radiation therapy. Using the median tumor regression rate of 34%, we divided the entire cohort into two groups, and found that the frequency distribution of PARP-1 gene rs3219073 had significant difference between these two groups (p < 0.05). These results showed that PARP-1 gene polymorphism may affect patient radiation sensitivity and predict the efficacy of radiotherapy. It therefore presents an opportunity for developing new therapeutic targets to improve radiotherapy outcome.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Tolerância a Radiação , Humanos , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Reparo do DNA/genética , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/radioterapia , Neoplasias Pulmonares/tratamento farmacológico , Polimorfismo de Nucleotídeo Único/genética , Tolerância a Radiação/genética
17.
RSC Adv ; 11(29): 17683-17693, 2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-35480180

RESUMO

Polychlorinated dibenzo-p-dioxins/dibenzofurans (PCDD/Fs) and polychlorinated dibenzothiophenes/thianthrenes (PCDT/TAs) are two groups of dioxin-like compounds with oxygen and sulfur substitution, respectively. Chlorophenols (CPs) and chlorothiophenols (CTPs) are direct precursors in PCDD/F and PCDT/TA formation. The formation of chlorophenoxy radicals (CPRs) and chlorothiophenoxy radicals (CTPRs) from chlorophenols (CPs) and chlorothiophenols (CTPs) with O(3P) is an important initial step for the formation of PCDD/Fs and PCDT/TAs, respectively. In this paper, the formation of CPRs/CTPRs from the complete series reactions of 19 CP/CTP congeners with O(3P) was studied using the density functional theory (DFT) method. The rate constants of each reaction were calculated using canonical variational transition state (CVT) theory along with a small-curvature tunneling (SCT) contribution over a wide temperature range of 600-1200 K. The effect of the chlorine substitution pattern on the structural parameters, thermochemical properties and rate constants in both CPs and CTPs was discussed. This study shows that the reactions between CPs and O(3P) can be affected by the chlorine substitution at the para-position, and the reactions between CTPs and O(3P) are mostly influenced by both ortho-substitutions. The thiophenoxyl-hydrogen abstraction from CTPs by O(3P) is more likely to occur than the phenoxyl-hydrogen abstraction from CPs by O(3P). Comparison of the reactivity of CP/CTPs with O(3P) with our previous work on CP/CTPs with H and OH shows that the order for phenoxyl-hydrogen abstraction potential is CP + OH > CP + O(3P) > CP + H, and the order for thiophenoxyl-hydrogen abstraction potential is CTP + O(3P) > CTP + H > CTP + OH.

18.
Food Chem Toxicol ; 147: 111901, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33279676

RESUMO

Functional components including ß-glucan, dietary fiber, resistant starch and polyphenols extracted from various coarse cereals have been reported to prevent high-fat diet (HFD) induced obesity via modulating gut microbiota. In this study, millet, maize, oat, soybean, and purple potato were ultrafine comminuted, mixed, and then extruded for the preparation of puffed mixture coarse cereals. HFD was used to investigate the effects of mixture coarse cereals on obesity and gut microbiota in mice. The results showed that dietary intake of mixture coarse cereals could decrease body weight gain and fat accumulation, improve the blood glucose tolerance and serum lipids levels, reduce the systemic inflammation, and down-regulate the expression of hepatic lipogenic genes. In addition, the levels of SCFAs and the composition of gut microbiota were investigated. The results indicated that mixture coarse cereals could promote the release of SCFAs, enhance the diversity of gut microbiota, and increase the relative abundance of Lactobacillus and Bifidobacterium, which might contribute to the anti-obesity activity. Present work suggested that the mixture coarse cereals could be developed as a nutraceutical for the prevention of HFD-induced obesity.


Assuntos
Citocinas/metabolismo , Dieta Hiperlipídica/efeitos adversos , Grão Comestível , Microbioma Gastrointestinal/efeitos dos fármacos , Obesidade/induzido quimicamente , Obesidade/prevenção & controle , Ração Animal/análise , Animais , Bactérias/genética , Glicemia , Citocinas/genética , DNA Bacteriano/genética , Fibras na Dieta , Ácidos Graxos Voláteis , Fezes/microbiologia , Inflamação , Masculino , Camundongos , Camundongos Endogâmicos C57BL
19.
Chemosphere ; 246: 125614, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31883478

RESUMO

Cadmium (Cd) is found widely in soil and is severely toxic for plants, causing oxidative damage in plant cells because of its heavy metal characteristics. The DNA damage response (DDR) is triggered in plants to cope with the Cd stress. The DNA mismatch repair (MMR) system known for its mismatch repair function determines DDR, as mispairs are easily generated by a translesional synthesis under Cd-induced genomic instability. Cd-induced mismatches are recognized by three heterodimeric complexes including MutSα (MSH2/MSH6), MutSß (MSH2/MSH3), and MutSγ (MSH2/MSH7). MutLα (MLH1/PMS1), PCNA/RFC, EXO1, DNA polymerase δ and DNA ligase participate in mismatch repair in turn. Meanwhile, ATR is preferentially activated by MSH2 to trigger DDR including the regulation of the cell cycle, endoreduplication, cell death, and recruitment of other DNA repair, which enhances plant tolerance to Cd. However, plants with deficient MutS will bypass MMR-mediated DDR and release the multiple-effect MLH1 from requisition of the MMR system, which leads to weak tolerance to Cd in plants. In this review, we systematically illustrate how the plant DNA MMR system works in a Cd-induced DDR, and how MMR genes regulate plant tolerance to Cd. Additionally, we also reviewed multiple epigenetic regulation systems acting on MMR genes under stress.


Assuntos
Cádmio/toxicidade , Dano ao DNA/efeitos dos fármacos , Reparo de Erro de Pareamento de DNA , Plantas/genética , Epigênese Genética , Humanos
20.
Sci Total Environ ; 723: 137987, 2020 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-32224394

RESUMO

Aerosol samples from all over the word contained 2-methyltetrol sulfate ester (MTS). We investigated the role of MTS in new particle formation (NPF) with aerosol nucleation precursors, including sulfuric acid (SA), water (W), ammonia (N), methylamine (MA), dimethylamine (DMA), and trimethylamine (TMA). The analysis was performed using quantum chemical approach, kinetic calculation and molecular dynamics (MD) simulations. The results proved that the molecular interactions in the clusters were mainly H-bonds and electrostatic interaction. The negative Gibbs free energy changes for all the studied MTS-containing clusters indicated that the formation of these clusters was thermodynamically favorable. The stability of the clusters was evaluated according to the total evaporation rate. Here, (MTS)(SA) and (MTS)(W) were the most and least stable cluster, respectively. MD simulations were used for time and spatial analysis of the role of the MTS-SA system. The results indicated that MTS can self-aggregate or absorb SA molecules into clusters, larger than the size of the critical cluster (approximately 1 nm), suggesting that MTS can initiate NPF by itself or together with SA.

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