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1.
Artigo em Inglês | MEDLINE | ID: mdl-34019975

RESUMO

CONTEXT: To provide effective end-of-life care education for health professions students, it is important to understand students' views of death in addition to their perceptions of educational needs and preferences. However, there is a lack of studies addressing interindividual variability in perceptions of end-of-life care educational needs among health professions students. OBJECTIVES: This study aimed to identify latent profiles of perceptions of end-of-life care educational needs among health professions students and examine whether the demographic characteristics, death-related events, death attitude, and death anxiety differed by need subgroup. METHODS: Through convenience sampling, health professions students from three universities in China were recruited between March 2020 and June 2020. Data were collected using a demographic information and death-related experience questionnaire, the End-of-Life Care Curriculum Needs Questionnaire, the End-of-Life Care Educational Needs Questionnaire, the Death Attitudes Profile-Revised, and the Templer's Death Anxiety Scale. RESULTS: A total of 1048 students completed the survey. Two classes of perceptions of end-of-life care educational needs were identified: approximately 29.80% of students belonged to a medium-need group class (1), and 70.20% belonged to a high-need group class (2). Being female and having knowledge of end-of-life care significantly increased the probability of membership in class 2. Students with the two latent profiles reported having varied curriculum needs. In addition, a positive attitude toward death and low death anxiety increased the probability of membership in class 1. CONCLUSION: Two classes of perceptions of end-of-life care educational needs were identified, and these classes were significantly associated with sex and death-related knowledge (P < 0.05). Interindividual variability should be considered in the future development of end-of-care curricula.

2.
Sensors (Basel) ; 20(18)2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32933069

RESUMO

A novel magnetic field sensor comprising a photonic crystal fiber (PCF) is designed and investigated based on surface plasmon resonance (SPR). We use finite element analysis in order to analyze the sensing characteristics of the magnetic field sensor. The simulation results show that the sensor is very sensitive to the change of refractive index and has good linearity in the refractive index range from 1.43-1.45. The thickness of the metal film and the metal material has great influence on the resonance wavelength and the peak of the loss spectrum, the diameter of the central air hole will affect SPP excitation. When the thickness of gold layer is 50 nm, the refractive index sensitivity is 4125 nm/RIU in the refractive index range from 1.43-1.45. Using the designed sensor for magnetic field sensing, the loss spectrum is red-shifted with the increase of the magnetic field, the highest magnetic field sensitivity can reach 61.25 pm/Oe in the range from 50 Oe to 130 Oe. The sensor not only has high sensitivity of refractive index, but it can also realize accurate measurement of magnetic field. It has huge application potential in complex environment, remote sensing, real-time monitoring, and other fields.

3.
Materials (Basel) ; 13(17)2020 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-32825800

RESUMO

In recent years, the achievement of the electromagnetically induced transparency (EIT) effect based on the guided-mode resonance (GMR) effect has attracted extensive attention. However, few works have achieved a double EIT-like effect using this method. In this paper, we numerically achieve a double EIT-like effect in a GMR system with a three-layer silicon nitride waveguide grating structure (WGS), using the multi-level atomic system model for theoretical explanation. In terms of slow light performance, the corresponding two delay times reach 22.59 ps and 8.43 ps, respectively. We also investigate the influence of wavelength detuning of different GMR modes on the transparent window and slow light performance. Furthermore, a wide-band flat-top transparent window was also achieved by appropriately adjusting the wavelength detuning between GMR modes. These results indicate that the EIT-like effect in the WGS has potential application prospects in low-loss slow optical devices, optical sensing, and optical communications.

4.
Sci Rep ; 8(1): 486, 2018 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-29323199

RESUMO

The tunable disorder of vacancies upon annealing is an important character of crystalline phase-change material Ge2Sb2Te5 (GST). A variety of resistance states caused by different degrees of disorder can lead to the development of multilevel memory devices, which could bring a revolution to the memory industry by significantly increasing the storage density and inspiring the neuromorphic computing. This work focuses on the study of disorder-induced carrier localization which could result in multiple resistance levels of crystalline GST. To analyze the effect of carrier localization on multiple resistant levels, the intrinsic field effect (the change in surface conductance with an applied transverse electric field) of crystalline GST was measured, in which GST films were annealed at different temperatures. The field effect measurement is an important complement to conventional transport measurement techniques. The field effect mobility was acquired and showed temperature activation, a hallmark of carrier localization. Based on the relationship between field effect mobility and annealing temperature, we demonstrate that the annealing shifts the mobility edge towards the valence-band edge, delocalizing more carriers. The insight of carrier transport in multilevel crystalline states is of fundamental relevance for the development of multilevel phase change data storage.

5.
J Environ Sci (China) ; 46: 203-13, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27521952

RESUMO

The photocatalytic oxidation of gaseous chlorobenzene (CB) by the 365nm-induced photocatalyst La/N-TiO2, synthesized via a sol-gel and hydrothermal method, was evaluated. Response surface methodology (RSM) was used to model and optimize the conditions for synthesis of the photocatalyst. The optimal photocatalyst was 1.2La/0.5N-TiO2 (0.5) and the effects of La/N on crystalline structure, particle morphology, surface element content, and other structural characteristics were investigated by XRD (X-ray diffraction), TEM (Transmission Electron Microscopy), FTIR (Fourier transform infrared spectroscopy), UV-vis (Ultraviolet-visible spectroscopy), and BET (Brunauer Emmett Teller). Greater surface area and smaller particle size were produced with the co-doped TiO2 nanotubes than with reference TiO2. The removal of CB was effective when performed using the synthesized photocatalyst, though it was less efficient at higher initial CB concentrations. Various modified Langmuir-Hinshelwood kinetic models involving the adsorption of chlorobenzene and water on different active sites were evaluated. Fitting results suggested that competitive adsorption caused by water molecules could not be neglected, especially for environments with high relative humidity. The reaction intermediates found after GC-MS (Gas chromatography-mass spectrometry) analysis indicated that most were soluble, low-toxicity, or both. The results demonstrated that the prepared photocatalyst had high activity for VOC (volatile organic compounds) conversion and may be used as a pretreatment prior to biopurification.


Assuntos
Poluentes Atmosféricos/química , Clorobenzenos/química , Modelos Químicos , Nanotubos/química , Titânio/química , Oxirredução
6.
Cell Biochem Biophys ; 71(2): 741-7, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25257130

RESUMO

Osteoclast is the only cell that can degrade bone tissue in vivo. Recent studies have shown the important role of cytoskeleton dynamics in osteolysis and the formation of podosome belt in osteoclasts. This process is regulated by the dynamic microtubule (MT) network. We treated osteoclast precursor cells Raw264.7 with low concentration of nocodazole (10 nM) and antineoplastic drug taxol (10 nM) to block MT turnover, and used end binding protein 1 fused to GFP to track the movement of microtubules in induced osteoclasts. We show that low concentrations of nocodazole and taxol interfere with the formation of podosome belt, and reduce TRAP activity of induced osteoclasts. These results suggest that the effect of taxol on MT dynamics may be used clinically to reduce osteoclast activity and potentially prevent development of osteoporosis and other metabolic bone diseases.


Assuntos
Microtúbulos/metabolismo , Osteoclastos/citologia , Osteoclastos/metabolismo , Fosfatase Ácida/metabolismo , Animais , Contagem de Células , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Membrana Celular/efeitos dos fármacos , Membrana Celular/metabolismo , Relação Dose-Resposta a Droga , Isoenzimas/metabolismo , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Microtúbulos/efeitos dos fármacos , Nocodazol/farmacologia , Osteoclastos/efeitos dos fármacos , Paclitaxel/farmacologia , Ligante RANK/farmacologia , Fosfatase Ácida Resistente a Tartarato
7.
PLoS One ; 9(11): e111527, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25375152

RESUMO

BACKGROUND: Since a previous meta-analysis reported that ultrasound guidance was associated with a higher first-attempt success rate in catheterization of the radial artery, a number of randomized controlled trials (RCTs) have reported inconsistent results. The aim of the present study is to conduct an updated meta-analysis to clarify the role of ultrasound guidance for radial artery catheterization. METHODS: A systematic literature search of PubMed, Embase, and Cochrane Central Register of Controlled Trials was conducted using specific search terms. Eligible studies were RCTs that compared ultrasound guidance with traditional palpation for radial artery catheterization. The Mantel-Haenszel method using the random effects model was adopted in this meta-analysis. RESULTS: Seven RCTs with 482 patients were included. Compared with traditional palpation, ultrasound guidance significantly increased the first-attempt success rate of radial artery catheterization (RR 1.51, 95% CI 1.07-2.14, P = 0.02). Subgroup analyses suggested that the superiority of ultrasound guidance for radial artery catheterization was significant when the technique was operated by experienced users, performed in small children and infants, and on elective procedures in the operating room. In addition, ultrasound guidance significantly reduced mean-attempts to success (WMD -1.13, 95% CI -1.58 to -0.69, P<0.00001), mean-time to success (WMD -74.77s, 95% CI -137.89s to -11.64s, P = 0.02), and the occurrence of hematoma (RR 0.17, 95% CI 0.07-0.41, P = 0.0001). CONCLUSIONS: The present meta-analysis suggests a clear benefit from ultrasound guidance for radial artery catheterization compared with the traditional palpation. Preliminary training and familiarization with the ultrasound-guided technique is needed before applying it for radial artery catheterization, especially for inexperienced operators.


Assuntos
Cateterismo Periférico/métodos , Artéria Radial/diagnóstico por imagem , Ultrassonografia de Intervenção/métodos , Humanos
8.
J Pain Symptom Manage ; 48(5): 893-902, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24793079

RESUMO

CONTEXT: Quality of life (QOL) is the main outcome measure for patients with advanced cancer at the end of life. The McGill Quality of Life Questionnaire (MQOL) is designed specifically for palliative care patients and has been translated and validated in Hong Kong and Taiwan. OBJECTIVES: This study aimed to investigate the QOL of patients with advanced cancer using the MQOL-Taiwan version after cultural adaptation to the Chinese mainland. METHODS: A cross-sectional survey design was used. QOL data from patients with advanced cancer were gathered from 13 hospitals including five tertiary hospitals, six secondary hospitals, and community health care service centers in Shanghai and analyzed. QOL was assessed using the MQOL-Chinese version. Statistical analyses were performed using descriptive statistics, multiple regression analysis, and Spearman rank correlation analysis. RESULTS: A total of 531 cancer patients (297 male and 234 female) in 13 hospitals were recruited into the study and administered the MQOL-Chinese. The score of the support subscale was highest (6.82), and the score of the existential well-being subscale was the lowest (4.65). The five physical symptoms most frequently listed on the MQOL-Chinese were pain, loss of appetite, fatigue, powerless, and dyspnea. Participants' sex, educational level, number of children, disclosure of the disease, and hospital size were associated with their overall QOL. The Spearman rank correlation analysis found that Karnofsky Performance Status scores correlated with the MQOL-Chinese single-item score, physical well-being, psychological well-being, existential well-being, and support domains (P < 0.05). CONCLUSION: Our results revealed the aspects of QOL that need more attention for Chinese palliative care patients with advanced cancer. The association between the characteristics of patients, Karnofsky Performance Status, and their QOL also was identified.


Assuntos
Neoplasias/diagnóstico , Neoplasias/psicologia , Cuidados Paliativos/métodos , Qualidade de Vida , Inquéritos e Questionários , Adolescente , Adulto , Idoso , China , Centros Comunitários de Saúde , Estudos Transversais , Feminino , Humanos , Idioma , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Centros de Cuidados de Saúde Secundários , Centros de Atenção Terciária , Adulto Jovem
9.
J Palliat Med ; 17(5): 545-52, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24708258

RESUMO

BACKGROUND: Accurate prediction of prognosis for cancer patients is important for good clinical decision making in therapeutic and care strategies. The application of prognostic tools and indicators could improve prediction accuracy. OBJECTIVE: This study aimed to develop a new prognostic scale to predict survival time of advanced cancer patients in China. METHODS: We prospectively collected items that we anticipated might influence survival time of advanced cancer patients. Participants were recruited from 12 hospitals in Shanghai, China. We collected data including demographic information, clinical symptoms and signs, and biochemical test results. Log-rank tests, Cox regression, and linear regression were performed to develop a prognostic scale. RESULTS: Three hundred twenty patients with advanced cancer were recruited. Fourteen prognostic factors were included in the prognostic scale: Karnofsky Performance Scale (KPS) score, pain, ascites, hydrothorax, edema, delirium, cachexia, white blood cell (WBC) count, hemoglobin, sodium, total bilirubin, direct bilirubin, aspartate aminotransferase (AST), and alkaline phosphatase (ALP) values. The score was calculated by summing the partial scores, ranging from 0 to 30. When using the cutoff points of 7-day, 30-day, 90-day, and 180-day survival time, the scores were calculated as 12, 10, 8, and 6, respectively. CONCLUSIONS: We propose a new prognostic scale including KPS, pain, ascites, hydrothorax, edema, delirium, cachexia, WBC count, hemoglobin, sodium, total bilirubin, direct bilirubin, AST, and ALP values, which may help guide physicians in predicting the likely survival time of cancer patients more accurately. More studies are needed to validate this scale in the future.


Assuntos
Cuidados Paliativos na Terminalidade da Vida/normas , Neoplasias/patologia , Neoplasias/fisiopatologia , Qualidade de Vida , Doente Terminal , Análise de Variância , China , Feminino , Humanos , Avaliação de Estado de Karnofsky , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Medição da Dor , Prognóstico , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Tempo
11.
Pain Manag Nurs ; 14(4): e142-e150, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24315266

RESUMO

To train pain nursing specialists through a pain education program, 20 nurses from six hospitals in Shanghai Province and seven in six provinces of China received the training of 2-month pain education and 4-month clinical practice. This nonrandomized pilot study examined the results of tests before and after the program, case report evaluations, future plan evaluations, clinical practice, and satisfaction questionnaire. After the program, the score of the test increased significantly compared with that before the program (44.1 ± 3.19; paired-sample t = 10.363; p < .0001). All of the participants thought that the program had broadened their vision, 19 (95%) thought that the program had raised the level of their theoretical knowledge in pain management, 17 (85%) thought that the program had improved their skills in clinical practice, and 15 (75%) thought that the program had played a role in enhancing their research abilities. Considering the whole program, most students (n = 17; 85%) were quite satisfied, and 3 (15%) were simply satisfied. By content analysis of the opening questions, we found that the participants had deeper and broader ideas about nurses' role and pain nursing specialists' responsibilities in pain management. The program improved nurses' attitudes, knowledge, and skills in pain management. The participants recognized pain nursing specialists' responsibilities in pain management more clearly.


Assuntos
Prática Avançada de Enfermagem/educação , Educação Continuada em Enfermagem/métodos , Manejo da Dor/enfermagem , Dor/enfermagem , Especialidades de Enfermagem/educação , Desenvolvimento de Pessoal/métodos , Atitude do Pessoal de Saúde , China , Educação Continuada em Enfermagem/organização & administração , Avaliação Educacional , Humanos , Internacionalidade , Pesquisa em Avaliação de Enfermagem , Recursos Humanos de Enfermagem no Hospital/educação , Desenvolvimento de Pessoal/organização & administração
12.
Cancer Nurs ; 36(4): 326-34, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23047798

RESUMO

BACKGROUND: Pain is a major problem for patients with advanced cancer and one of the most frequent and disturbing of all cancer-related symptoms. Researchers continue to report that cancer pain remains undertreated. Inadequate pain control can significantly affect the patient's quality of life and may in turn affect the patient's will to live or comply with treatment recommendations. A better understanding of the experience of cancer pain management is important in identifying factors responsible for undertreated pain. OBJECTIVE: This study aimed to obtain the experience of cancer pain management. INTERVENTIONS: We used a phenomenological approach to explore the status of cancer pain management through participants' experience. Semistructured interviews were conducted with 14 family caregivers, patients, and acquaintances and 14 health professionals (nurses and physicians) from a regional tertiary hospital in northwest China. Data were collected by in-depth interviews. We used a qualitative description after full transcription of every interview. Analysis involved the identification of themes and the development of a taxonomy of participants' experience of cancer pain management. RESULTS: Taxonomy used in this study is to identify, code, group, and name meaning units of the transcribed interviews by reading through repeatedly to obtain an initial sense. Four themes were identified: (1) marginalization, (2) hopelessness and helplessness, (3) deficiency of access and resources, and (4) expectations related to pain. CONCLUSION: Findings from this study suggest that the situation of patients with undertreated cancer pain continues. IMPLICATIONS FOR PRACTICE: Special attention should be paid by policymakers, professionals, and family caregivers to the marginalized group of cancer patients who suffer with pain.


Assuntos
Área Carente de Assistência Médica , Neoplasias/complicações , Manejo da Dor/métodos , Dor Intratável/etiologia , Dor Intratável/terapia , Adulto , Idoso , Cuidadores/estatística & dados numéricos , China , Estudos Transversais , Feminino , Acesso aos Serviços de Saúde/estatística & dados numéricos , Serviços de Assistência Domiciliar/normas , Serviços de Assistência Domiciliar/tendências , Humanos , Entrevistas como Assunto , Masculino , Pessoa de Meia-Idade , Determinação de Necessidades de Cuidados de Saúde , Neoplasias/diagnóstico , Neoplasias/terapia , Manejo da Dor/tendências , Dor Intratável/fisiopatologia , Serviços de Saúde Rural/normas , Serviços de Saúde Rural/tendências , Índice de Gravidade de Doença , Resultado do Tratamento
13.
Huan Jing Ke Xue ; 33(2): 511-7, 2012 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-22509590

RESUMO

The experiment was carried out in a sequencing batch reactor (SBR), using granular sludge with 90% shortcut nitrification accumulation ratio, which had been cultivated by the laboratory to seed the reactor. The effects of temperature on characteristics, stability, nitrogen conversion properties and activity of short-cut nitrification granular sludge were investigated. The results show that the temperature has a significant influence on structure and short-cut nitrification performance of short-cut nitrification granular sludge. 30 degrees C was the optimum temperature for shortcut nitrification granular sludge cultivation, and the granules were more compact which led better flocculation and settleability. SVI and average diameter of sludge reached up to 39 mL x g(-1) and 3.03 mm, respectively. The nitrification accumulation was maintained at 96.17% during this period. When the temperature was at 25 degrees C, the granules changed to a loose-structure along with the electronegativity increased as well as the hydrophobicity decreased, which was due to the increase of EPS and decreased ratio of protein to polysaccharide. The granules disintegrated during this period, at the same time, the nitrification accumulation ratio was below 35%. It can be seen that the shortcut nitrification performance was destroyed. At 15 degrees C, the shortcut nitrification sludge also disintegrated and had a looser structure. However, the oxygen penetration depth increased at a lower temperature, which made the relative quantity of ammonia oxidizing bacteria (AOB) in reactor increased, the nitrification accumulation was around 68% ultimately.


Assuntos
Reatores Biológicos/microbiologia , Nitrificação , Esgotos/química , Temperatura , Eliminação de Resíduos Líquidos/métodos , Floculação , Nitritos/isolamento & purificação , Nitritos/metabolismo , Nitrogênio/isolamento & purificação , Nitrogênio/metabolismo
14.
Cancer Lett ; 313(2): 137-44, 2011 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-22030254

RESUMO

Previous research has documented that a subpopulation of pancreatic cancer cells, named cancer stem cells (CSCs), harbor stem cell-like properties. Here, we examined the efficacy of combined treatments of salinomycin and gemcitabine in human pancreatic cancer cells. Salinomycin inhibited the growth of CSCs, while gemcitabine suppressed the viability of non-CSCs. Consistently, in vivo studies showed that salinomycin combined with gemcitabine could eliminate the engraftment of human pancreatic cancer more effectively than the individual agents. These data indicated that administration of salinomycin, which targets CSCs, may constitute a potential therapeutic strategy for improving the efficacy of gemcitabine to eradicate pancreatic cancer.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Desoxicitidina/análogos & derivados , Neoplasias Pancreáticas/tratamento farmacológico , Piranos/farmacologia , Antígeno AC133 , Animais , Antígenos CD/metabolismo , Antimetabólitos Antineoplásicos/administração & dosagem , Antimetabólitos Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Desoxicitidina/administração & dosagem , Desoxicitidina/farmacologia , Citometria de Fluxo , Glicoproteínas/metabolismo , Humanos , Masculino , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/efeitos dos fármacos , Neoplasias Pancreáticas/patologia , Peptídeos/metabolismo , Piranos/administração & dosagem , Ensaios Antitumorais Modelo de Xenoenxerto
15.
Dalton Trans ; 40(34): 8611-21, 2011 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-21804968

RESUMO

Three novel Ru(II) complexes of the general formula [Ru(N-N)(2)(Norharman)(2)](SO(3)CF(3))(2), where N-N = 2,2'-bipyridine (bpy, 1), 1,10-phenanthroline (phen, 2), 4,7-diphenyl-1,10-phenanthroline (DIP, 3) and Norharman (9H-pyrido[3,4-b]indole) is a naturally occurring ß-carboline alkaloid, have been synthesized and characterized. The molecular structures of 1 and 2 have been determined by X-ray diffraction analysis. The cellular uptake efficiencies, in vitro cytotoxicities and apoptosis-inducing properties of these complexes have been extensively explored. Notably, 1-3 exhibit potent antiproliferative activities against a panel of human cancer cell lines with IC(50) values lower than those of cisplatin. Further studies show that 1-3 can cause cell cycle arrest in the G0/G1 phase and induce apoptosis through mitochondrial dysfunction and reactive oxygen species (ROS) generation. In vitro DNA binding studies have also been conducted to provide information about the possible mechanism of action.


Assuntos
Apoptose/efeitos dos fármacos , Citotoxinas/síntese química , Harmina/análogos & derivados , Compostos Organometálicos/toxicidade , Rutênio/toxicidade , Alcaloides/síntese química , Alcaloides/farmacologia , Antineoplásicos/síntese química , Produtos Biológicos/síntese química , Produtos Biológicos/farmacologia , Carbolinas , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , DNA/metabolismo , Harmina/química , Humanos , Concentração Inibidora 50 , Mitocôndrias/efeitos dos fármacos , Compostos Organometálicos/química , Compostos Organometálicos/farmacologia , Farmacocinética , Espécies Reativas de Oxigênio , Rutênio/química , Rutênio/farmacologia , Difração de Raios X
16.
BMC Cell Biol ; 12: 30, 2011 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-21729331

RESUMO

BACKGROUND: Isolation of mouse MSCs (mMSCs) with normal ploidy from bone marrow remains challenging. mMSCs isolated under 20% O(2) are frequently contaminated by overgrown hematopoietic cells, and could also be especially vulnerable to oxidative damage, resulting in chromosomal instability. Culture under low oxygen or extracellular matrix (ECM) improves proliferation of MSCs in several species. We tested the hypothesis that culture under low oxygen in combination with ECM prepared from mouse embryonic fibroblast (MEF-ECM) could be used to purify proliferative mMSCs, and to reduce oxidative damage and maintain their chromosomal stability. RESULTS: Optimization of culture conditions under 20% O(2) resulted in immortalization of mMSCs, showing extensive chromosome abnormalities, consistent with previous studies. In contrast, culture under low oxygen (2% O(2)) improved proliferation of mMSCs and reduced oxidative damage, such that mMSCs were purified simply by plating at low density under 2% O(2). MEF-ECM reduced oxidative damage and enhanced proliferation of mMSCs. However, these isolated mMSCs still exhibited high frequency of chromosome abnormalities, suggesting that low oxygen or in combination with MEF-ECM was insufficient to fully protect mMSCs from oxidative damage. Notably, antioxidants (alpha -phenyl-t-butyl nitrone (PBN) and N-acetylcysteine (NAC)) further reduced DNA damage and chromosomal abnormalities, and increased proliferation of mMSCs. mMSCs isolated by the combination method were successfully used to generate induced pluripotent stem (iPS) cells by ectopic expression of Oct4, Sox2, Klf4 and c-Myc. CONCLUSIONS: We have developed a technique that allows to reduce the number of karyotypic abnormalities for isolation of primary mMSCs and for limited culture period by combination of low oxygen, MEF-ECM, antioxidants and low density plating strategy. The effectiveness of the new combination method is demonstrated by successful generation of iPS cells from the isolated mMSCs. However, a culture system for mMSCs still is needed to prevent all the anomalies, especially after a long-term culture period.


Assuntos
Células da Medula Óssea/citologia , Matriz Extracelular/metabolismo , Células-Tronco Mesenquimais/citologia , Estresse Oxidativo , Ploidias , Animais , Antioxidantes/farmacologia , Células da Medula Óssea/metabolismo , Proliferação de Células , Separação Celular , Células Cultivadas , Aberrações Cromossômicas , Fibroblastos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Camundongos , Células-Tronco Pluripotentes/citologia , Espécies Reativas de Oxigênio/metabolismo
17.
J Hazard Mater ; 189(1-2): 69-75, 2011 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-21367524

RESUMO

This study aims at evaluating the impacts of PAM addition on activated sludge performance. Four lab-scale sequencing batch reactors (SBRs), each with a working volume of 3L, were investigated with different PAM concentrations. Experiments were conducted with varying organic loading rate and the sludge volume index (SVI), particle size, zeta potential, specific oxygen uptake rate (SOUR), mixed liquor suspended solids (MLSS), COD and ammonium removal efficiency were monitored over a 105-day period. The results showed that all of the PAM addition not only improved the removal efficiencies of COD and ammonium, but also exhibited some advantages on sludge performance. It was found that the sludge performance of settling property, flocculation and microbial activity increased with increasing concentration of PAM. However, high level of PAM (1mg/L) led to the formation of large amounts of loose-structure flocs, which eliminated dissolved oxygen transfer and caused the sludge disintegration, resulting in bad settleability and lower microbial activity. In this way, when the dosage of PAM was 0.1mg/L, the sludge had the best settling property and activity.


Assuntos
Resinas Acrílicas/farmacologia , Biodegradação Ambiental , Esgotos/microbiologia , Carbono , Oxigênio , Compostos de Amônio Quaternário , Esgotos/química
18.
Hum Mol Genet ; 20(7): 1339-52, 2011 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-21239471

RESUMO

Parthenogenetic embryonic stem cells (pESCs) have been generated in several mammalian species from parthenogenetic embryos that would otherwise die around mid-gestation. However, previous reports suggest that pESCs derived from in vivo ovulated (IVO) mature oocytes show limited pluripotency, as evidenced by low chimera production, high tissue preference and especially deficiency in germline competence, a critical test for genetic integrity and pluripotency of ESCs. Here, we report efficient generation of germline-competent pESC lines (named as IVM pESCs) from parthenogenetic embryos developed from immature oocytes of adult mouse ovaries following in vitro maturation (IVM) and artificial activation. In contrast, pESCs derived from IVO oocytes show defective germline competence, consistent with previous reports. Further, IVM pESCs resemble more ESCs from fertilized embryos (fESCs) than do IVO pESCs on genome-wide DNA methylation and global protein profiles. In addition, IVM pESCs express higher levels of Blimp1, Lin28 and Stella, relative to fESCs, and in their embryoid bodies following differentiation. This may indicate differences in differentiation potentially to the germline. The mechanisms for acquisition of pluripotency and germline competency of IVM pESCs from immature oocytes remain to be determined.


Assuntos
Antígenos de Diferenciação/biossíntese , Células-Tronco Embrionárias , Oócitos , Ovário , Partenogênese , Células-Tronco Pluripotentes , Animais , Células-Tronco Embrionárias/citologia , Células-Tronco Embrionárias/metabolismo , Feminino , Camundongos , Oócitos/citologia , Oócitos/metabolismo , Ovário/citologia , Ovário/metabolismo , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo
19.
J Med Chem ; 53(21): 7613-24, 2010 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-20958054

RESUMO

The role of autophagy in cancer development and response to cancer therapy has been a subject of debate. Here we demonstrate that a series of ruthenium(II) complexes containing a ß-carboline alkaloid as ligand can simultaneously induce autophagy and apoptosis in tumor cells. These Ru(II) complexes are nuclear permeable and highly active against a panel of human cancer cell lines, with complex 3 displaying activities greater than those of cisplatin. The antiproliferative potentialities of 1-3 are in accordance with their relative lipophilicities, cell membrane penetration abilities, and in vitro DNA binding affinities. Complexes 1-3 trigger release of reactive oxygen species (ROS) and attenuation of ROS by scavengers reduced the sub-G1 population, suggesting ROS-dependent apoptosis. Inhibition of ROS generation also reduces autophagy, indicating that ROS triggers autophagy. Further studies show that suppression of autophagy using pharmacological inhibitors (3-methyladenine and chloroquine) enhances apoptotic cell death.


Assuntos
Antineoplásicos/síntese química , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Carbolinas/síntese química , Núcleo Celular/metabolismo , Complexos de Coordenação/síntese química , Mitocôndrias/fisiologia , Rutênio , Antineoplásicos/química , Antineoplásicos/farmacologia , Carbolinas/química , Carbolinas/farmacologia , Linhagem Celular Tumoral , Permeabilidade da Membrana Celular , Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , DNA/química , Ensaios de Seleção de Medicamentos Antitumorais , Proteínas de Fluorescência Verde/genética , Humanos , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-Atividade
20.
Zhongguo Zhong Yao Za Zhi ; 35(12): 1556-9, 2010 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-20815206

RESUMO

OBJECTIVE: The aim of this study is to analyze the processing mechanism of calamine. METHOD: XRD, TEM and IR were adopted to analyze the structures and the components of original and calcined calamine. Their antibacterial activities were also determined. RESULT: The results indicated that zinc carbonate in original calamine was decomposed into zinc oxide after processing at 700 degrees C for 1 hour using original calamine of 40 mesh, and the particle size was smaller than before processing. All of ZnO, ZnCO3 and Zn5 (CO3) 2 (OH) 6 had antibacterial activitives. CONCLUSION: Original calamine is deposed to ZnO after being calcined for 1 h at 700 degrees C and wet milling. The content of ZnO and antibacterial activity of calcined calamine are better than those of original calamine, moreover, the particle size diminishes and become dimensional uniformity, and the contents of dissolved impurities is decreased. The antibacterial activitives of original and calcined calamine are decided by zinc.


Assuntos
Antibacterianos/química , Compostos Férricos/química , Óxido de Zinco/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Combinação de Medicamentos , Compostos Férricos/farmacologia , Tamanho da Partícula , Óxido de Zinco/farmacologia
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