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1.
Molecules ; 23(2)2018 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-29463048

RESUMO

In this study, two novel boron dipyrromethene-based photosensitizers (BDP3 and BDP6) substituted with three or six trifluoromethyl groups have been synthesized and characterized with various spectroscopic methods, and their photo-physical, photo-chemical, and photo-biological properties have also been explored. The two photosensitizers are highly soluble and remain nonaggregated in N,N-dimethylformamide as shown by the intense and sharp Q-band absorption. Under red light irradiation (λ = 660 nm, 1.5 J/cm²), both photosensitizers show high and comparable cytotoxicity towards HepG2 human hepatocarcinoma and HeLa human cervical carcinoma cells with IC50 values of 0.42-0.49 µM. The high photocytotoxicity of BDP3 and BDP6 can be due to their high cellular uptake and low aggregation tendency in biological media, which result in a high efficiency to generate reactive oxygen species inside the cells. Confocal laser fluorescence microscopic studies indicate that they have superior selective affinities to the mitochondria and lysosomes of HepG2 and HeLa cells. The results show that these two trifluoromethyl boron dipyrromethene derivatives are potential anticancer agents for photodynamic therapy.


Assuntos
Antineoplásicos/química , Boro/química , Fotoquimioterapia , Fármacos Fotossensibilizantes/química , Antineoplásicos/síntese química , Antineoplásicos/uso terapêutico , Boro/uso terapêutico , Sobrevivência Celular/efeitos dos fármacos , Células HeLa , Humanos , Luz , Lisossomos/química , Mitocôndrias/efeitos dos fármacos , Fármacos Fotossensibilizantes/síntese química , Fármacos Fotossensibilizantes/uso terapêutico , Porfobilinogênio/análogos & derivados , Porfobilinogênio/química , Porfobilinogênio/uso terapêutico , Relação Estrutura-Atividade
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(4): 1010-4, 2015 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-26197592

RESUMO

As a biological adsorbent, Living Deinococcus radiodurans was used for removing radionuclide uranium in the aqueous solution. The effect factors on biosorption of radionuclide uranium were researched in the present paper, including solution pH values and initial uranium concentration. Meanwhile, the biosorption mechanism was researched by the method of FTIR and SEM/EDS. The results show that the optimum conditions for biosorption are as follows: pH = 5, co = 100 mg · L(-1) and the maximum biosorption capacity is up to 240 mgU · g(-1). According to the SEM results and EDXS analysis, it is indicated that the cell surface is attached by lots of sheet uranium crystals, and the main biosorpiton way of uranium is the ion exchange or surface complexation. Comparing FTIR spectra and FTIR fitting spectra before and after biosorption, we can find that the whole spectra has a certain change, particularly active groups (such as amide groups of the protein, hydroxy, carboxyl and phosphate group) are involved in the biosorption process. Then, there is a new peak at 906 cm(-1) and it is a stretching vibration peak of UO2(2+). Obviously, it is possible that as an anti radiation microorganism, Deinococcus radiodurans could be used for removing radionuclide uranium in radiation environment.


Assuntos
Deinococcus/metabolismo , Urânio/metabolismo , Biodegradação Ambiental , Microscopia Eletrônica de Varredura , Radioisótopos , Soluções , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Front Nutr ; 10: 1036572, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36875852

RESUMO

Purpose: This study explored the relationship between the prognostic nutritional index (PNI) and overall survival rate (OS) in patients with nasopharyngeal carcinoma (NPC), and established and validated an effective nomogram to predict clinical outcomes. Methods: This study included 618 patients newly diagnosed with locoregionally advanced NPC. They were divided into training and validation cohorts at a ratio of 2:1 based on random numbers. The primary endpoint of this study was OS, progression-free survival (PFS) was the second endpoint. A nomogram was drawn from the results of multivariate analyses. Harrell's concordance index (C-index), area under the receiver operator characteristic curve (AUC), and decision curve analysis (DCA) were used to evaluate the clinical usefulness and predictive ability of the nomogram and were compared to the current 8th edition of the International Union Against Cancer/American Joint Committee (UICC/AJCC) staging system. Results: The PNI cutoff value was 48.1. Univariate analysis revealed that age (p < 0.001), T stage (p < 0.001), N stage (p = 0.036), tumor stage (p < 0.001), PNI (p = 0.001), lymphocyte-neutrophil ratio (NLR, p = 0.002), and lactate dehydrogenase (LDH, p = 0.009) were significantly associated with OS, age (p = 0.001), T-stage (p < 0.001), tumor stage (p < 0.001), N-stage (p = 0.011), PNI (p = 0.003), NLR (p = 0.051), and LDH (p = 0.03) were significantly associated with PFS. Multivariate analysis showed that age (p < 0.001), T-stage (p < 0.001), N-stage(p = 0.02), LDH (p = 0.032), and PNI (p = 0.006) were significantly associated with OS, age (p = 0.004), T-stage (<0.001), N-stage (<0.001), PNI (p = 0.022) were significantly associated with PFS. The C-index of the nomogram was 0.702 (95% confidence interval [CI]: 0.653-0.751). The Akaike information criterion (AIC) value of the nomogram for OS was 1142.538. The C-index of the TNM staging system was 0.647 (95% CI, 0.594-0.70) and the AIC was 1163.698. The C-index, DCA, and AUC of the nomogram demonstrated its clinical value and higher overall net benefit compared to the 8th edition of the TNM staging system. Conclusion: The PNI represents a new inflammation-nutrition-based prognostic factor for patients with NPC. In the proposed nomogram, PNI and LDH were present, which led to a more accurate prognostic prediction than the current staging system for patients with NPC.

4.
Front Oncol ; 11: 735817, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34722284

RESUMO

PURPOSE: To identify whether chemoradiotherapy improves survival of stage I nasopharyngeal carcinoma (NPC). MATERIALS AND METHODS: NPC patients were extracted from the Surveillance, Epidemiology, and End Results database between 2010 and 2015. Pathologically confirmed stage T1N0M0 (the 7th edition AJCC) were investigated. Overall survival (OS) and cancer-specific survival (CSS) were compared between the radiotherapy and chemoradiotherapy groups using the Kaplan-Meier method and propensity score matching (PSM) analyses. RESULTS: This study included 91 (40.27%) patients in the chemoradiotherapy group and 135 (59.73%) patients in the radiotherapy group. Before PSM, chemoradiotherapy was associated with worse 3-year OS (74.31 vs 87.23%; P = 0.025) and 5-year OS (64.28 vs 83.12%; P = 0.001) compared to those associated with radiotherapy. Similarly, chemoradiotherapy showed worse 3-year CSS (87.01 vs 96.97%; P = 0.028) and 5-year CSS (80.39 vs. 96.97%; P = 0.002) than those of radiotherapy. After PSM, chemoradiotherapy revealed worse 5-year OS (63.10 vs. 82.49%; P = 0.031) and CSS (80.95 vs. 93.70%; P = 0.016) than radiotherapy. The multivariate regression analysis revealed that chemoradiotherapy was an independent risk prognostic factor for OS and CSS before and after PSM. CONCLUSION: Radiotherapy alone is recommended for stage I NPC patients.

5.
Mitochondrial DNA B Resour ; 5(1): 614-615, 2020 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-33366671

RESUMO

Calophaca sinica Rehd. is a tree species with high economic value, whose resource has been declining due to unreasonable exploitation. In this study, we sequenced, assembled, and annotated the complete chloroplast genome of C. sinica. The whole chloroplast genome size is 129,345 bp, it lacks an inverted repeat (IR) region. The GC content of the whole chloroplast genome is 34.51%. The chloroplast genome comprises 112 unique genes, including 77 protein-coding genes (PCGs), 30 transfer RNA (tRNA) genes, and 5 ribosomal RNA (rRNA) genes. Phylogenetic analyses of chloroplast genomes derived from 15 species indicated that C. sinica is close to Caragana and Tibetia species in Papilionoideae.

6.
Mol Cell Biol ; 25(10): 3934-44, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15870268

RESUMO

Repair of chromosome double-strand breaks (DSBs) is central to cell survival and genome integrity. Nonhomologous end joining (NHEJ) is the major cellular repair pathway that eliminates chromosome DSBs. Here we report our genetic screen that identified Rsc8 and Rsc30, subunits of the Saccharomyces cerevisiae chromatin remodeling complex RSC, as novel NHEJ factors. Deletion of RSC30 gene or the C-terminal truncation of RSC8 impairs NHEJ of a chromosome DSB created by HO endonuclease in vivo. rsc30Delta maintains a robust level of homologous recombination and the damage-induced cell cycle checkpoints. By chromatin immunoprecipitation, we show recruitment of RSC to a chromosome DSB with kinetics congruent with its involvement in NHEJ. Recruitment of RSC to a DSB depends on Mre11, Rsc30, and yKu70 proteins. Rsc1p and Rsc2p, two other RSC subunits, physically interact with yKu80p and Mre11p. The interaction of Rsc1p with Mre11p appears to be vital for survival from genotoxic stress. These results suggest that chromatin remodeling by RSC is important for NHEJ.


Assuntos
Montagem e Desmontagem da Cromatina , Dano ao DNA , Reparo do DNA , DNA Fúngico/metabolismo , Proteínas de Ligação a DNA/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/metabolismo , Sequência de Aminoácidos , Ciclo Celular , Cromatina/metabolismo , Proteínas Cromossômicas não Histona/química , Proteínas Cromossômicas não Histona/metabolismo , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/genética , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Endodesoxirribonucleases/genética , Endodesoxirribonucleases/metabolismo , Exodesoxirribonucleases/genética , Exodesoxirribonucleases/metabolismo , Genes Fúngicos/genética , Teste de Complementação Genética , Dados de Sequência Molecular , Fenótipo , Ligação Proteica , Subunidades Proteicas/química , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Recombinação Genética , Saccharomyces cerevisiae/citologia , Proteínas de Saccharomyces cerevisiae/química , Proteínas de Saccharomyces cerevisiae/genética , Fatores de Transcrição/química , Fatores de Transcrição/genética
7.
Mol Cell Biol ; 23(23): 8820-8, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14612421

RESUMO

End joining of double-strand breaks (DSBs) requires Ku proteins and frequently involves base pairing between complementary terminal sequences. To define the role of terminal base pairing in end joining, two oppositely oriented HO endonuclease cleavage sites separated by 2.0 kb were integrated into yeast chromosome III, where constitutive expression of HO endonuclease creates two simultaneous DSBs with no complementary end sequence. Lack of complementary sequence in their 3' single-strand overhangs facilitates efficient repair events distinctly different from when the 3' ends have a 4-bp sequence base paired in various ways to create 2- to 3-bp insertions. Repair of noncomplementary ends results in a set of nonrandom deletions of up to 302 bp, annealed by imperfect microhomology of about 8 to 10 bp at the junctions. This microhomology-mediated end joining (MMEJ) is Ku independent, but strongly dependent on Mre11, Rad50, and Rad1 proteins and partially dependent on Dnl4 protein. The MMEJ also occurs when Rad52 is absent, but the extent of deletions becomes more limited. The increased gamma ray sensitivity of rad1Delta rad52Delta yku70Delta strains compared to rad52Delta yku70Delta strains suggests that MMEJ also contributes to the repair of DSBs induced by ionizing radiation.


Assuntos
DNA Helicases , Reparo do DNA/fisiologia , Endodesoxirribonucleases/metabolismo , Endonucleases/metabolismo , Exodesoxirribonucleases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Antígenos Nucleares/genética , Antígenos Nucleares/metabolismo , Pareamento de Bases , Sequência de Bases , Quebra Cromossômica , Cromossomos Fúngicos/genética , Cromossomos Fúngicos/metabolismo , DNA Ligase Dependente de ATP , DNA Ligases/genética , DNA Ligases/metabolismo , Reparo do DNA/genética , Enzimas Reparadoras do DNA , DNA Fúngico/genética , DNA Fúngico/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Endodesoxirribonucleases/genética , Endonucleases/genética , Exodesoxirribonucleases/genética , Genes Fúngicos , Autoantígeno Ku , Modelos Biológicos , Dados de Sequência Molecular , Mutação , Proteína Rad52 de Recombinação e Reparo de DNA , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética
8.
Oncotarget ; 8(28): 46211-46218, 2017 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-28515352

RESUMO

Two-dimensional conventional radiotherapy (2D-CRT) and intensity-modulated radiotherapy (IMRT) are effective for control of nasopharyngeal carcinoma (NPC). The purpose of this study was to compare the quality of life (QoL) of stage II NPC patients treated with 2D-CRT versus IMRT. We conducted a cross-sectional study of 106 patients with stage II NPC treated with 2D-CRT (n = 47) versus IMRT (n = 59) between June 2008 and June 2013. For all subjects, disease-free survival was more than 3 years. QoL was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30) questions and the Head and Neck 35 (EORTC QLQ-H&N35) questions. Patients receiving IMRT with or without concurrent chemotherapy had better outcomes in head and neck related symptoms and general aspects of QoL than those receiving 2D-CRT with or without concurrent chemotherapy. Thus, IMRT improves the QoL of patients with stage II NPC as compared to 2D-CRT.


Assuntos
Carcinoma/radioterapia , Neoplasias de Cabeça e Pescoço/radioterapia , Neoplasias Nasofaríngeas/radioterapia , Radioterapia de Intensidade Modulada/métodos , Adulto , Idoso , Carcinoma/tratamento farmacológico , Carcinoma/mortalidade , Estudos Transversais , Feminino , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/mortalidade , Estadiamento de Neoplasias , Qualidade de Vida , Inquéritos e Questionários , Análise de Sobrevida , Resultado do Tratamento
9.
Oncotarget ; 8(8): 14029-14038, 2017 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-28152511

RESUMO

The purpose of this study was to compare the quality of life (QoL) of stage II nasopharyngeal carcinoma (NPC) patients treated with radiotherapy (RT) versus concurrent chemoradiotherapy (CCRT). In a cross-sectional study, these patients were treated with RT (n = 55) or CCRT (n = 51) between June 2008 and June 2013. For all subjects, disease-free survival was more than 3 years. QoL was assessed using the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire-Core 30 (EORTC QLQ-C30) questions and the Head and Neck 35 (EORTC QLQ-H&N35) questions. RT had better outcomes than CCRT for global QoL, functional scales, symptom scales of fatigue and insomnia, financial problems, and weight gain. Survivors receiving 1 cycle of concurrent chemotherapy had worse QoL outcomes than survivors receiving 2 cycles of concurrent chemotherapy. Patients receiving 3 cycles of concurrent chemotherapy had the best QoL outcomes. Thus, CCRT adversely affects the QoL of patients with stage II NPC as compared to radiotherapy.


Assuntos
Carcinoma/tratamento farmacológico , Carcinoma/radioterapia , Quimiorradioterapia/efeitos adversos , Neoplasias Nasofaríngeas/tratamento farmacológico , Neoplasias Nasofaríngeas/radioterapia , Qualidade de Vida , Adulto , Idoso , Carcinoma/mortalidade , Estudos Transversais , Intervalo Livre de Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/mortalidade , Inquéritos e Questionários
10.
Oncotarget ; 8(44): 78096-78104, 2017 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-29100451

RESUMO

We compared treatment outcomes in patients with stage II nasopharyngeal carcinoma (NPC) treated with intensity-modulated radiotherapy (IMRT) or two-dimensional conventional radiotherapy (2D-CRT). Stage II (2010 UICC/AJCC staging system) NPC patients treated with IMRT (n = 178) or 2D-CRT (n = 73) between January 2007 and December 2014 were retrospectively analyzed. Patients were matched using the propensity score-matching method. The primary endpoint was overall survival (OS). Secondary endpoints were local relapse-free survival (LRFS), regional relapse-free survival (RRFS), distant metastasis-free survival (DMFS), and disease-free survival (DFS). Acute and late toxicity reactions to IMRT and 2D-CRT were also compared. In an unmatched cohort of 251 patients, no significant survival differences were found between those receiving IMRT and those receiving 2D-CRT (5-year OS, 95.67% vs 94.44%, P = 0.0556; LRFS, 97.34% vs 98.59%, P = 0.6656; RRFS, 99.26% vs 100%, P = 0.6785; DMFS, 96.5% vs 98.63%, P = 0.7910; DFS, 92.2% vs 97.24%, P = 0.8719). In the propensity-matched cohort of 146 patients, 5-year OS (97.06% vs 94.44%, P = 0.1325), LRFS (96.75% vs 98.59%, P = 0.8869), RRFS (100% vs 100%, P = 1.0000), DMFS (98.63% vs 98.63%, P = 0.4225), and DFS (95.37% vs 97.24%, P = 0.5634) were similar between patients treated with IMRT or 2D-CRT. However, IMRT correlated with fewer acute and late toxicity reactions. Thus although IMRT provides no survival advantage, it has a lower incidence of toxicity than 2D-CRT in stage II NPC patients.

11.
Oncotarget ; 7(44): 71951-71959, 2016 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-27713125

RESUMO

Secondary malignancies are a common complication for patients receiving radiotherapy. Here, we compared rates of secondary malignancies after partial breast irradiation (PBI) and whole breast irradiation (WBI). The MEDLINE, EMBASE, and the Cochrane Library databases were systematically searched to identify relevant randomized clinical trials comparing PBI with WBI in breast cancer patients treated with breast-conserving therapy. Four studies including 2,185 patients were selected. Compared to WBI, the pooled odds ratios (OR) for contralateral breast cancer were 0.86 (95% confidence interval (CI) 0.31-2.42; p = 0.78) after 5 years and 1.15 (95% CI 0.43-3.09; p = 0.78) after 10 years for PBI. The pooled ORs for secondary non-breast cancer were 0.91 (95% CI 0.49-1.67; p = 0.77) after 5 years and 1.20 (95% CI 0.39-3.66; p = 0.75) after 10 years for PBI compared to WBI. These results demonstrate that the risk of secondary malignancies is similar for PBI and WBI after breast-conserving radiotherapy.


Assuntos
Neoplasias da Mama/radioterapia , Mama/efeitos da radiação , Segunda Neoplasia Primária/etiologia , Quimiorradioterapia , Feminino , Humanos , Mastectomia Segmentar
12.
Sci Signal ; 3(109): ra12, 2010 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-20159853

RESUMO

Phosphorylation is a universal mechanism for regulating cell behavior in eukaryotes. Although protein kinases target short linear sequence motifs on their substrates, the rules for kinase substrate recognition are not completely understood. We used a rapid peptide screening approach to determine consensus phosphorylation site motifs targeted by 61 of the 122 kinases in Saccharomyces cerevisiae. By correlating these motifs with kinase primary sequence, we uncovered previously unappreciated rules for determining specificity within the kinase family, including a residue determining P-3 arginine specificity among members of the CMGC [CDK (cyclin-dependent kinase), MAPK (mitogen-activated protein kinase), GSK (glycogen synthase kinase), and CDK-like] group of kinases. Furthermore, computational scanning of the yeast proteome enabled the prediction of thousands of new kinase-substrate relationships. We experimentally verified several candidate substrates of the Prk1 family of kinases in vitro and in vivo and identified a protein substrate of the kinase Vhs1. Together, these results elucidate how kinase catalytic domains recognize their phosphorylation targets and suggest general avenues for the identification of previously unknown kinase substrates across eukaryotes.


Assuntos
Proteínas Quinases/metabolismo , Saccharomyces cerevisiae/metabolismo , Sequência de Aminoácidos , Dados de Sequência Molecular , Fosforilação , Proteínas Quinases/química , Saccharomyces cerevisiae/enzimologia , Especificidade por Substrato
13.
J Biol Chem ; 281(7): 3954-63, 2006 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-16365046

RESUMO

Saccharomyces cerevisiae Rad53, the ortholog of mammalian Chk2, is an essential protein kinase in DNA damage and DNA replication checkpoint pathways. Consecutive phosphatidyl inositol kinase-like kinase (PIKK)-dependent and PIKK-independent steps in activation of Rad53 are key steps for controlling and transmitting diverse downstream responses to DNA damage. However, these activities have not been demonstrated in vitro in defined systems. Here, we have shown that enzymatically dephosphorylated purified Rad53 autoactivates in vitro through a phosphorylation-dependent mechanism. Kinetic analysis demonstrated that autophosphorylation results in a more than 9-fold increase in protein kinase activity. Autophosphorylation was Rad53 concentration-dependent, indicating that the reaction follows an intermolecular mechanism. DNA damage induced oligomerization of a subset of Rad53 molecules in vivo. At low concentrations of Rad53, preincubation of Rad53 with immune complexes containing the Mec1/Ddc2 complex can activate Rad53 kinase activity. Our findings showed that Mec1/Ddc2 complexes can directly activate Rad53 through a phosphorylation-dependent mechanism, and more generally, supported the hypothesis that PIKKs regulate Chk2 orthologs through phosphorylation. Moreover, this work has substantiated a model for PIKK-independent amplification of Rad53 activation (and by extension, activation of other Chk2 orthologs) mediated by inter-Rad53 phosphorylation.


Assuntos
Proteínas de Ciclo Celular/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/fisiologia , Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Ciclo Celular/química , Proteínas de Ciclo Celular/fisiologia , Quinase do Ponto de Checagem 2 , Dano ao DNA , Ativação Enzimática , Peptídeos e Proteínas de Sinalização Intracelular , Fosfoproteínas/fisiologia , Fosforilação , Proteínas Serina-Treonina Quinases/química , Proteínas de Saccharomyces cerevisiae/química
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