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1.
J Int Med Res ; 47(5): 1936-1947, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30843447

RESUMO

OBJECTIVE: To explore correlations between body mass index (BMI), preoperative systemic immune-inflammation index (SII) and endocrine therapy resistance, and evaluate BMI and SII as predictors of resistance, in patients with luminal breast cancer. METHODS: This retrospective study included patients with luminal breast cancer who underwent endocrine therapy at Hebei General Hospital. Relationships between BMI and SII subgroups, and clinicopathological parameters were analysed using χ2-tests. Disease-free survival was assessed using Log-rank statistics. Multivariate analysis of factors related to disease progression were analysed using Cox proportional hazards model. RESULTS: Out of 161 patients, those with normal BMI and low SII had significantly lower endocrine resistance rates versus those with high BMI and SII, and BMI was significantly positively correlated with SII. High BMI or SII was associated with significantly lower disease-free survival rates. Hazard ratios for disease progression risk were 6.036, 3.508 and 1.733, for SII, BMI and TNM stage, respectively. CONCLUSION: In patients with luminal breast cancer, high BMI (>23 kg/m2) and SII (>518 × 109/L) levels may predict high endocrine resistance rates. BMI, SII and TNM stage were independent prognostic factors for endocrine therapy resistance.


Assuntos
Peso Corporal , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Resistencia a Medicamentos Antineoplásicos , Hormônios/uso terapêutico , Inflamação/imunologia , Índice de Massa Corporal , Feminino , Humanos , Inflamação/patologia , Pessoa de Meia-Idade , Análise Multivariada , Modelos de Riscos Proporcionais , Curva ROC
2.
Guang Pu Xue Yu Guang Pu Fen Xi ; 35(4): 1048-51, 2015 Apr.
Artigo em Japonês | MEDLINE | ID: mdl-26197600

RESUMO

To reduce the limit of detection (LOD) and allow the accurate determination of Ge, a dry ashing method was performed to enrich the Ge in plant samples. A method for the determination.of trace Ge in plant samples by HG-AFS was established. Study of the effect of temperature on the ashing of plant samples showed that no volatile loss of Ge occurred even at 900 °C. Additional experiments indicated that a 4 h burning process at 600 °C would be sufficient to fully ash the plant samples. Various digestion methods (involving nitric acid, hydrofluoric acid, and sulfuric acid digestion methods) for ashed samples were investigated. High-temperature ashing with large sample weights was used, which could reduce the reagent doses and the method's LOD effectively and simultaneously, the precision of the method was improved. The method's LOD was 0.27 ng · g(-1), and the relative standard deviation was 3.99%-6.81%. Verified with national biological reference materials (grade I), the proposed method was accurate and reliable.


Assuntos
Germânio/análise , Plantas/química , Espectrometria de Fluorescência , Espectrofotometria Atômica
3.
Anal Chem ; 86(23): 11570-7, 2014 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-25343694

RESUMO

Hafnium content and its change are of significance in geochemistry and cosmochemistry; however, the determination of hafnium has always been problematic in analytical chemistry. In this paper, a new idea is proposed for the determination of hafnium in geochemical samples, including rocks, soils, and stream sediments. Through the comparison of two conventional open-type acid digestion methods (HF-HNO3-HClO4 and HF-HNO3-H2SO4), it was found that although neither of these methods could fully digest the zirconium and hafnium in a sample, the zirconium and hafnium digestion behaviors in one sample were consistent in the 60 experimental geochemical reference materials with different properties, so the experimentally determined Zr/Hf ratio in solution could be used to calculate the hafnium content in a sample. In addition, possible mass spectral interferences during the determination of zirconium and hafnium by high resolution inductively coupled plasma mass spectrometry (HR-ICPMS) were studied, and it was found that the mass spectral interferences of the selected isotopes (90)Zr and (178)Hf could be neglected. The mass spectral behaviors of (90)Zr and (178)Hf were also very consistent during the determination by HR-ICPMS. Since the hafnium content was calculated using the ratio value, all of the errors (including the errors in weighing process, the accidental errors during operation and the instrument fluctuation in the determination) of the Zr/Hf ratio could be effectively reduced or even eliminated. The relative standard deviation of the actual samples was lower than 3.2%, and the detection limit of the method (considering the dilution effect and matrix effect during measurement of the Zr/Hf ratio and zirconium content) was 0.04 µg/g. The proposed method could satisfy the requirement for the determination of hafnium in geochemical samples.

4.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 10): m1299, 2012 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-23125614

RESUMO

In the title complex, {[Zn(NCS)(2)(C(15)H(15)N(9))(2)]·H(2)O}(n), the Zn(II) ion is located on an inversion centre and is six-coordinated in a distorted octa-hedral geometry, coordinated by N atoms from four bridging 1,3,5-tris-(1,2,4-triazol-1-ylmeth-yl)benzene (ttmb) ligands and two terminal SCN(-) counter-anions. Two of the three triazol groups in each ttmb ligand link the Zn(II) atoms, forming a looped-chain structure along [0-11]. The lattice water molecule shows half-occupancy due to disorder around an inversion centre.

5.
Acta Crystallogr Sect E Struct Rep Online ; 68(Pt 6): o1709, 2012 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-22719500

RESUMO

In the title mol-ecule, C(16)H(19)BrO(3), all non-H atoms apart from the Br atom are approximately coplanar, with a maximum deviation of 0.242 (4) Å. The C-C-C-Br torsion angle is 66.5 (4)°.

6.
PLoS One ; 7(12): e52780, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23300774

RESUMO

BACKGROUND: Preterm birth, the birth of an infant prior to 37 completed weeks of gestation, is the leading cause of perinatal morbidity and mortality. Preterm infants are at greater risk of respiratory, gastrointestinal and neurological diseases. Despite significant research in developed countries, little is known about the causes of preterm birth in many developing countries, especially China. This study investigates the association between sciodemographic data, obstetric risk factor, and preterm birth in five Maternal and Child Health hospitals in Beijing, China. METHODS AND FINDINGS: A case-control study was conducted on 1391 women with preterm birth (case group) and 1391 women with term delivery (control group), who were interviewed within 48 hours of delivery. Sixteen potential factors were investigated and statistical analysis was performed by univariate analysis and logistic regression analysis. Univariate analysis showed that 14 of the 16 factors were associated with preterm birth. Inter-pregnancy interval and inherited diseases were not risk factors. Logistic regression analysis showed that obesity (odds ratio (OR) = 3.030, 95% confidence interval (CI) 1.166-7.869), stressful life events (OR = 5.535, 95%CI 2.315-13.231), sexual activity (OR = 1.674, 95%CI 1.279-2.191), placenta previa (OR 13.577, 95%CI 2.563-71.912), gestational diabetes mellitus (OR = 3.441, 95%CI1.694-6.991), hypertensive disorder complicating pregnancy (OR = 6.034, 95%CI = 3.401-10.704), history of preterm birth (OR = 20.888, 95%CI 2.519-173.218) and reproductive abnormalities (OR = 3.049, 95%CI 1.010-9.206) were independent risk factors. Women who lived in towns and cities (OR = 0.603, 95%CI 0.430-0.846), had a balanced diet (OR = 0.533, 95%CI 0.421-0.675) and had a record of prenatal care (OR = 0.261, 95%CI 0.134-0.510) were less likely to have preterm birth. CONCLUSIONS: Obesity, stressful life events, sexual activity, placenta previa, gestational diabetes mellitus, hypertensive disorder complicating pregnancy, history of preterm birth and reproductive abnormalities are independent risk factors to preterm birth. Identification of remedial factors may inform local health and education policy.


Assuntos
Diabetes Gestacional , Obesidade/complicações , Placenta Prévia , Pré-Eclâmpsia , Nascimento Prematuro/etiologia , Adulto , Estudos de Casos e Controles , China , Feminino , Maternidades , Humanos , Acontecimentos que Mudam a Vida , Análise Multivariada , Razão de Chances , Gravidez , Resultado da Gravidez , Estudos Retrospectivos , Fatores de Risco , Comportamento Sexual , Adulto Jovem
7.
Cancer Invest ; 28(7): 689-97, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20636107

RESUMO

Urokinase plasminogen activator (uPA) correlates closely with breast cancer metastasis via triggering the degradation of divergent matrix proteins. Here, uPA was selectively knocked down in breast carcinoma MDA-MB-231 cells by siRNAs. The in vitro migration of MDA-MB-231 cells was effectively suppressed accompanied by a decrease in extracellular MMP-9 activities. The colony formation ability of MDA-MB-231 cells was inhibited following uPA knockdown, while the proliferation was not affected. The uPA knockdown in MDA-MB-231 cells caused significantly suppressed tumor metastasis in nude mice. Thus, siRNAs targeted to uPA have implications in the development of novel approaches to preventing breast cancer metastasis.


Assuntos
Neoplasias da Mama/genética , Neoplasias da Mama/patologia , RNA Interferente Pequeno/farmacologia , Ativador de Plasminogênio Tipo Uroquinase/genética , Animais , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica , Metástase Neoplásica/prevenção & controle
8.
Cancer Biol Ther ; 5(7): 860-6, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16861916

RESUMO

Increased resistance to apoptosis is a hallmark of many tumor cells. Survivin, a member of IAP family protein, is expressed in many human cancers and plays an important role in protecting cells from apoptosis. Here we show that vector-based small interfering RNAs (siRNA) stably knockdown survivin expression in several cancer cell lines, leading to increased apoptotic rate in response to different proapoptotic stimuli, such as doxorubicin or TNF-alpha. The apoptotic susceptibility was dependent on divergent levels of survivin expression. The stable transfectants exhibited abnormal morphology, suppressed cell growth, enhanced spontaneous apoptosis and cell cycle hindrance. Furthermore, in nude mice xenografts of survivin-positive tumors, cells expressing survivin-targeted siRNAs exhibited decreased tumor formation and reduced angiogenesis. Results from these studies: (1) provide direct evidence that intracellular silencing of survivin by siRNA sensitizes human tumor cells to apoptosis; (2) define survivin as a promising molecular target for cancer therapy; and (3) suggest the potential applicability of survivin-targeted siRNA for treating human tumors, probably in combination with chemotherapy.


Assuntos
Neoplasias da Mama/terapia , Terapia Genética , Proteínas Associadas aos Microtúbulos/antagonistas & inibidores , Proteínas de Neoplasias/antagonistas & inibidores , Neovascularização Patológica/terapia , RNA Interferente Pequeno/genética , Neoplasias do Colo do Útero/terapia , Animais , Apoptose , Neoplasias da Mama/irrigação sanguínea , Proliferação de Células , Terapia Combinada , Resistencia a Medicamentos Antineoplásicos , Feminino , Expressão Gênica , Vetores Genéticos/genética , Humanos , Proteínas Inibidoras de Apoptose , Camundongos , Camundongos Nus , Proteínas Associadas aos Microtúbulos/genética , Proteínas de Neoplasias/genética , Survivina , Neoplasias do Colo do Útero/irrigação sanguínea , Ensaios Antitumorais Modelo de Xenoenxerto
9.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 25(2): 164-7, 2003 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-12905712

RESUMO

OBJECTIVE: To investigate the dual effects by the delta opioid receptor agonists DPDPE on the delayed rectified potassium channels in NG108-15 cells. METHODS: A series of outward currents were evoked in NG108-15 cells by depolarizing voltage from -50 mV to +80 mV at holding potential of -90 mV. These currents were delayed rectified potassium currents. Relatively selected delta opioid receptor agonists DPDPE of higher and lower concentrations were used to modulate the delayed rectified K+ current in NG108-15 cells. Opioid receptor antagonist Naloxone (NAL) and relatively selected delta opioid receptor antagonist Naltrindole (NTI) were used in the present experiments for the characterization of the actions of opioid receptors. RESULTS: The relatively higher concentrations of delta opioid receptor agonist DPDPE (> or = 10(-6) mol/L) significantly increased the amplitude of the delayed rectified K+ current. On the contrary, the relatively lower concentrations of DPDPE (< or = 10(-12) mol/L) decreased the amplitude of the delayed rectified K+ current (P < 0.05). Furthermore both the increase and decrease were time-dependent. CONCLUSIONS: delta opioid receptor agonist has dual regulatory effects on the delayed rectified potassium channels in NG108-15 cells.


Assuntos
D-Penicilina (2,5)-Encefalina/farmacologia , Naltrexona/análogos & derivados , Canais de Potássio Corretores do Fluxo de Internalização/efeitos dos fármacos , Receptores Opioides delta/agonistas , Animais , Membrana Celular/metabolismo , Glioma/metabolismo , Glioma/patologia , Células Híbridas/metabolismo , Camundongos , Naloxona/farmacologia , Naltrexona/farmacologia , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Técnicas de Patch-Clamp , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Ratos , Células Tumorais Cultivadas
10.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 25(3): 297-300, 2003 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-12905743

RESUMO

OBJECTIVE: To observe the role of G protein in the dual regulation of opioid receptor agonist on the delayed rectified potassium channels. METHODS: Using whole-cell patch-clamp techniques applied to NG108-15 cells, investigate the effect of opioid receptor agonist on the delayed rectified potassium channels by administration of Guanosine-5'-0'-2-thiociphosphate (GDP beta S), Pertusis Toxin (PTX), Tetroacetic acid nueleoside diphosphate kinase (NDPK) and Adenosine-3' 5' cyclic monophosphate cAMP in the pipette solution. RESULTS: (1) GDP beta S could block the changes induced by both high and low concentration of (D-Pen2.5)-enkephalin (DPDPE) (P < 0.05). (2) PTX could inhibit the excitative regulation on K+ channel by high concentration of DPDPE (P < 0.05). But CTX had no effect on K+ channel caused by DPDPE. (3) UDP could block the excitative effect of K+ channel by high concentration of NDPK, while have no changes on the inhibitory effect caused by low concentration of opioid agonists. (4) cAMP took part in the regulation in high concentration of agonist administration (P < 0.05), while no changes for low concentration of agonists. CONCLUSIONS: Dual changes were observed on delayed rectifier potassium channel by agonist treatment on NG108-15 cells. The excitative effect was Gi/o coupled in high concentration of agonist incubation, related to cAMP. While the inhibitory effect was possibly induced by G protein beta gamma subunit directly.


Assuntos
Proteínas de Ligação ao GTP/fisiologia , Guanosina Monofosfato/análogos & derivados , Células Híbridas/metabolismo , Canais de Potássio Corretores do Fluxo de Internalização/metabolismo , Receptores Opioides/agonistas , Animais , D-Penicilina (2,5)-Encefalina/farmacologia , Glioma/metabolismo , Glioma/patologia , Guanosina Monofosfato/farmacocinética , Células Híbridas/patologia , Camundongos , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Técnicas de Patch-Clamp , Toxina Pertussis/farmacologia , Ratos , Tionucleotídeos/farmacocinética
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