RESUMO
The development of efficient and earth-abundant electrocatalysts for overall water splitting is important but still challenging. Herein, iron phosphate (FePi) electrode is synthesized using a successive ionic layer deposition and reaction (SILAR) method on a nickel foam substrate at room temperature and is used as a bifunctional electrocatalyst for water splitting. The prepared FePi electrodes show excellent electrocatalytic activity and stability for the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). The FePi electrode exhibits low overpotential of 230â¯mV and 157â¯mV towards the OER and HER, respectively, with superior long-term stability. As a result, an electrolyzer that exploits FePi as both the anode and the cathode is constructed, which requires a cell potential of 1.67â¯V to deliver a 10â¯mAâ¯cm-2 current density in 1â¯M KOH solution. The exceptional features of the catalyst lie in its structure and active metal sites, increasing surface area, accelerated electron transport and promoted reaction kinetics. This study may provide a facile and scalable approach to design a high-efficiency, earth-abundant electrocatalyst for water splitting.
RESUMO
The purpose of this study was to adapt the Attitudes Toward Acute Mental Health Scale (ATAMHS) into the Korean language and culture and then to determine the reliability and validity of it by administering it to a sample of Korean nursing students and nurses. We conducted a psychometric evaluation that included a two-step item analysis (analysis and reanalysis), exploratory factor analysis and concurrent validity. The ATAMHS was translated into Korean by bilingual nurses. Then, 429 participants (224 undergraduate nursing students and 205 nurses, all with psychiatric experience) completed the translated version of the ATAMHS. The item analysis revealed that nine items correlated poorly with the rest; thus, they were deleted from the scale. The final Korean version of the scale, which we refer to as the Korean version of the ATAMHS (ATAMHS-K), contains 24 items. The ATAMHS-K showed good internal consistency. Exploratory factor analysis revealed three factors (professional perspective, semantic differentials and positive attitudes) that explained 39.5% of the variance. The ATAMHS-K had strong correlations with the Korean version of the Community Attitudes towards the Mentally Ill Scale, thus confirming the concurrent validity. Therefore, the ATAMHS-K demonstrated acceptable psychometric properties as a measure of attitudes toward acute mental health in Korean nursing students and nurses.
Assuntos
Atitude do Pessoal de Saúde , Conhecimentos, Atitudes e Prática em Saúde , Enfermeiras e Enfermeiros/psicologia , Psicometria/instrumentação , Estudantes de Enfermagem/psicologia , Inquéritos e Questionários/normas , Adulto , Feminino , Humanos , Unidade Hospitalar de Psiquiatria , República da Coreia , Adulto JovemRESUMO
Eight compounds were isolated from the stems of Brucea mollis by various chromatographic techniques such as column chromatography on silica gel and Sephadex LH-20, and preparative HPLC, and their structures were elucidated as bruceolline O (1), 1-(1-beta-glucopyranosyl)-1H-indole-3-carbaldehyde (2), canthin-6-one (3), 11-hydroxycanthin-6-one (4), 9-methoxycanthin-6-one (5), 4-methoxycanthin-6-one (6), infractin (7), and beta-carboline-1-propionic acid (8). The cytotoxic activities of compounds 1-8 against HCT-8 and A549 human cell lines were determined, but none of them exhibited significant activity (IC 50 > 10 micromol x L(-1)). Among them, compound 1 is a new indole alkaloid, and compounds 2 and 5-7 were isolated from this plant for the first time.
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Brucea/química , Alcaloides Indólicos/isolamento & purificação , Plantas Medicinais/química , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Carbolinas/química , Carbolinas/isolamento & purificação , Carbolinas/farmacologia , Linhagem Celular Tumoral , Humanos , Alcaloides Indólicos/química , Alcaloides Indólicos/farmacologia , Estrutura Molecular , Caules de Planta/químicaRESUMO
A bacterium (Paracoccus sp. YM3) capable of degrading carbofuran was isolated from carbofuran-contaminated sludge. The strain was shown to metabolize carbofuran (50 mg L(-1)) to carbofuran-7-phenol in minimal salt medium within 6 days in which the pesticide was the only source of carbon. Carbofuran and its main metabolite were analyzed by high performance liquid chromatography (HPLC). The addition of an other carbon source led to accelerated biodegradation. The relevant degrading-enzyme was intracellular and inducible. A tobacco hypersensitivity experiment showed that YM3 could eliminate carbofuran in soils effectively and safely. This is the first report of a Paracoccus sp. that could degrade carbofuran. The present study may provide a basis for biotreatment of wastewaters and bioremediation of carbofuran-contaminated soils.
Assuntos
Biodegradação Ambiental , Carbofurano/química , Inseticidas/química , Paracoccus/metabolismo , Proteínas de Bactérias/genética , Biodegradação Ambiental/efeitos dos fármacos , Regulação da Expressão Gênica , Espaço Intracelular/enzimologia , Dados de Sequência Molecular , Compostos Orgânicos/metabolismo , Paracoccus/classificação , Paracoccus/patogenicidade , Paracoccus/fisiologia , Filogenia , RNA Ribossômico 16S/genética , Solo/análise , Sacarose/farmacologia , Fatores de Tempo , Nicotiana/microbiologiaRESUMO
Vapor adsorption is an important process influencing the migration and the fates of many organic pollutants in the environment. In this study, adsorption of ethylene glycol (EG) vapor onto single crystal alpha-Al2O3 (0001) and fused SiO2 (amorphous) surfaces was studied with sum frequency generation spectroscopy, a well-suited surface specific technique for probing interfacial phenomena atthe molecular scale. Air-aqueous EG solutions were also investigated to compare to the adsorption at the air-solid interface in the presence of water vapor. The gauche conformer of EG molecules dominates the air-aqueous EG solution interface, and EG molecules act as hydrogen acceptors at the air-liquid interface. Water and surface hydrophilic/ hydrophobic properties play important roles for the adsorption of EG onto silica and alumina surfaces. The adsorbed EG molecules interact in different ways at the two different oxide surfaces. EG molecules weakly physisorb onto the alpha-Al2O3 (0001) surface by forming relatively weak hydrogen bonds with surface water molecules. On the silica surface, the suppression of the silanol OH stretching peak indicates that EG molecules form hydrogen bonds with silanol OH groups.
Assuntos
Etilenoglicol/química , Dióxido de Silício/química , Adsorção , Aerossóis , Solo , Análise Espectral , Volatilização , Água/químicaRESUMO
Dendritic cells (DCs) are extremely efficient antigen presenting cells (APCs) that are potent stimulators of both T and B cell-mediated immune responses. Although DCs are normally present in very small numbers in the peripheral blood (PB), recent advances have made it possible to generate relatively large numbers of cells in culture. DCs can be differentiated in vitro from various cellular sources, including bone marrow (BM), cord blood (CB) and PB mononuclear cells (PBMCs). Although a wide variety of conditions have been reported to be able to support DC generation, the majority of research and clinical protocols to date differentiate DCs from precursors using granulocyte-macrophage colony stimulating factor (GM-CSF) in combination with either tumor necrosis factor-(TNF-)alpha or interleukin (IL)-4. However, a diverse array of cytokines has been shown to be able to induce DC differentiation under a variety of conditions. According to recent reports, cytokines such as IL-2, IL-6, IL-7, IL-13, IL-15 and hepatocyte growth factor (HGF), in combination or even, in some cases, alone, can contribute to the generation of DCs from either monocytes or CD34+ cells. Although the majority of cytokine combinations include GM-CSF, some do not. For example, Flt3 ligand (FL), in conjuction with IL-6 (in the absence of GM-CSF), has been reported to be able to induce DC differentiation from BM cells in a murine system. Other agents can play a dual role in DC activity. CD40 ligand (CD40L), as a single agent, has been shown to be able to generate DCs from PB monocytes, while numerous other reports have also demonstrated its role as a potent maturation factor. In contrast, for other cytokines such as IL-16 or IL-17, although there is no data for a role in DC generation, they have been reported to be involved in promoting DC maturation in vitro as defined by upregulation of costimulatory molecules, major histocompatibility complex (MHC) antigens and antigen presenting/T lymphocyte stimulatory capacity. Furthermore, cytokines such as stem cell factor (SCF) and FL have been shown to dramatically enhance in vivo DC recovery. The wide variety of cytokines and conditions that have been shown to be able to influence DC differentiation and activity to amply demonstrate the extreme heterogeneity found in the DC population, something that is reflected in the diverse phenotypes, functions and ontogeny displayed by DCs. This diversity may account for the large number of roles that have been attributed to DCs in the development and function of the immune system and, in turn, emphasizes the potential as well as the challenges of modifying specific aspects of the immune response system by manipulating specific DC subpopulations.
Assuntos
Citocinas/fisiologia , Células Dendríticas/imunologia , Animais , Células Apresentadoras de Antígenos/citologia , Células Apresentadoras de Antígenos/imunologia , Células Dendríticas/citologia , Humanos , Interferons/fisiologia , Interleucinas/fisiologiaRESUMO
After decades of decline, tuberculosis has emerged as a global health challenge. In the setting of HIV immunocompromise, TB occurs frequently, early, and often atypically. New infections can take an accelerated course. The usual tests for diagnosing Mycobacterium tuberculosis infection are less sensitive when CD4+ counts are low. Increased prevalence of treatment failure, drug-resistant strains, and nosocomial transmission of multidrug-resistant TB are discussed as are new diagnostic tests that will accelerate the time to diagnosis and allow better epidemiologic tracking. Early recognition, isolation, appropriate therapy, and environmental controls that will protect staff and patients from the risk of exposure are also described.
Assuntos
Infecções Oportunistas Relacionadas com a AIDS/complicações , Tuberculose/complicações , Antituberculosos/administração & dosagem , Demografia , Surtos de Doenças , Quimioterapia Combinada , Emigração e Imigração , Soropositividade para HIV/complicações , Pessoas Mal Alojadas , Humanos , Controle de Infecções/métodos , Transmissão de Doença Infecciosa do Paciente para o Profissional/prevenção & controle , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/patogenicidade , Prisioneiros , Teste Tuberculínico , Tuberculose/diagnóstico , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Tuberculose Pulmonar/complicações , Estados Unidos/epidemiologiaRESUMO
The therapeutic activity of ftorafur was compared to that of 5-fluorouracil (5-FU) in a number of tumor systems. The drugs were active against ip L1210 leukemia when administered ip, sc, or orally. Administration every fourth day x 3 proved to be the most effective treatment schedule for both drugs, although significant activity was seen on all treatment schedules tested. Both congeners had activity against sc implanted L1210 leukemia as well as a limited effect on the ic implanted tumor. 5-FU produced greater increases in lifespan of mice bearing L1210 leukemia than did ftorafur. 5-FU was also more effective against ip B16 melanoma and ip Gardner 6C3HED lymphosarcoma. Ftorafur was ineffective in the treatment of mice bearing ip P388 leukemia, a tumor which is quite sensitive to 5-FU. At approximately equimolar doses both drugs produced a persistent inhibition of 2'-deoxyuridine incorporation into DNA of L1210 cells in vivo. Ftorafur produced a greater inhibition of uridine incorporation into RNA than did 5-FU, which may account for the lower therapeutic activity of ftorafur. In combination chemotherapy of L1210 leukemia 5-FU plus ftorafur was no more effective than 5-FU alone, neither of the congeners was synergistic with either adriamycin or actinomycin D, and in combination with methotrexate therapeutic synergism was observed with 5-FU but not with ftorafur. After eight transplant generations of exposure to ftorafur, a subline of L1210 leukemia became totally resistant to ftorafur and simultaneously cross-resistant to 5-FU. Doses of ftorafur and 5-FU which were optimally effective in mice bearing the parental L1210 line were lethal to mice implanted with the ftorafur-resistant subline. When treatment of the resistant subline was discontinued after nine transplant generations of exposure to ftorafur, sensitivity to 5-FU returned after three transplant generations without ftorafur. The subline retained its resistance to ftorafur until eight transplant generations after cessation of ftorafur treatment. Another subline of L1210 leukemia exposed to 5-fU for 20 transplant generations proved to be completely resistant to 5-fu and cross-resistant to ftorafur. The mutual cross-resistance between ftorafur and 5-FU supports the contention that ftorafur acts primarily as a depot form of 5-FU.
Assuntos
Fluoruracila/uso terapêutico , Neoplasias Experimentais/tratamento farmacológico , Animais , Carcinoma/tratamento farmacológico , Linhagem Celular , Resistência a Medicamentos , Quimioterapia Combinada , Feminino , Fluoruracila/administração & dosagem , Leucemia L1210/tratamento farmacológico , Leucemia Experimental/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Linfoma não Hodgkin/tratamento farmacológico , Masculino , Melanoma/tratamento farmacológico , Metotrexato/uso terapêutico , Camundongos , Tegafur/uso terapêuticoRESUMO
The LD50 of intraperitoneally (ip) injected daunorubicin in nonleukemic mice (1.8 mg/kg, q4d times 3) can be increased several fold by the concomitant ip injection of ICRF-159. In addition, the survival of leukemic mice treated with daunorubicin and ICRF-159 on Days 1, 5, and 9 after ip inoculation of L1210 tumor cells was substantially greater than after treatment with either drug alone. This potentiation of survival with combination treatment usually occurred with doses of daunorubicin greater than the LD50 of daunorubicin alone. The LD50 of subcutaneously (sc) injected daunorubicin alone (14.0 mg/kg, q4d times 3) was not increased by concomitant ip treatment with ICRF-159. However, when leukemic mice were treated sc with daunorubicin and ip with ICRF-159 on Days 1, 5, and 9 after ip injection of L1210 leukemia cells, survival was greater than with treatment with either drug alone. The toxicity of ip injected adriamycin was not reduced by ICRF-159, but treatment of leukemic mice with this combination was more effective in prolonging survival than treatment with either drug alone. Combination treatment with daunorubicin plus ICRF-159 showed much less therapeutic enhancement against sc implanted L1210 leukemia than against the ip implanted tumor.
Assuntos
Daunorrubicina/uso terapêutico , Doxorrubicina/uso terapêutico , Leucemia L1210/tratamento farmacológico , Piperazinas/uso terapêutico , Razoxano/uso terapêutico , Animais , Daunorrubicina/toxicidade , Doxorrubicina/toxicidade , Sinergismo Farmacológico , Quimioterapia Combinada , Dose Letal Mediana , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Razoxano/toxicidade , Fatores de TempoAssuntos
Antineoplásicos/uso terapêutico , Leucemia L1210/tratamento farmacológico , Compostos de Mostarda Nitrogenada/uso terapêutico , Triazenos/uso terapêutico , Animais , Antineoplásicos/administração & dosagem , Antineoplásicos/toxicidade , Biotransformação , Relação Dose-Resposta a Droga , Estabilidade de Medicamentos , Meia-Vida , Ácido Clorídrico/uso terapêutico , Imidazóis/administração & dosagem , Imidazóis/uso terapêutico , Imidazóis/toxicidade , Camundongos , Camundongos Endogâmicos , Compostos de Mostarda Nitrogenada/administração & dosagem , Compostos de Mostarda Nitrogenada/toxicidade , Sais/uso terapêutico , Solubilidade , Soluções , Suspensões , Triazenos/administração & dosagem , Triazenos/toxicidadeAssuntos
Amidas/uso terapêutico , Antineoplásicos/uso terapêutico , Citarabina/uso terapêutico , Imidazóis/uso terapêutico , Leucemia L1210/tratamento farmacológico , Metotrexato/uso terapêutico , Compostos de Nitrosoureia/uso terapêutico , Triazenos/uso terapêutico , Animais , Ascite , Quimioterapia Combinada , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Fatores de TempoAssuntos
Acetilcisteína/farmacologia , Antineoplásicos/toxicidade , Leucemia L1210/tratamento farmacológico , Compostos Organofosforados/toxicidade , Oxazinas/toxicidade , Animais , Antineoplásicos/uso terapêutico , Óxidos P-Cíclicos/uso terapêutico , Óxidos P-Cíclicos/toxicidade , Sinergismo Farmacológico , Feminino , Hemorragia/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Transplante de Neoplasias , Compostos Organofosforados/uso terapêutico , Oxazinas/uso terapêutico , Fatores de Tempo , Transplante Homólogo , Doenças da Bexiga Urinária/induzido quimicamenteAssuntos
Aminas/uso terapêutico , Antineoplásicos/uso terapêutico , Cloretos/uso terapêutico , Ciclofosfamida/uso terapêutico , Leucemia L1210/tratamento farmacológico , Piperazinas/uso terapêutico , Platina/uso terapêutico , Animais , Azacitidina/uso terapêutico , Camptotecina/uso terapêutico , Carmustina/uso terapêutico , Citarabina/uso terapêutico , Sinergismo Farmacológico , Emetina/uso terapêutico , Fluoruracila/uso terapêutico , Cetonas/uso terapêutico , Masculino , Metotrexato/uso terapêutico , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Propano/uso terapêutico , Fatores de TempoAssuntos
Leucemia L1210/tratamento farmacológico , Alquilantes/uso terapêutico , Amidas/uso terapêutico , Animais , Antibióticos Antineoplásicos/uso terapêutico , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Citarabina/administração & dosagem , Citarabina/uso terapêutico , Imidazóis/uso terapêutico , Masculino , Metotrexato/uso terapêutico , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Compostos de Nitrosoureia/uso terapêutico , Purinas/uso terapêutico , Pirimidinas/uso terapêutico , Fatores de Tempo , Ureia/uso terapêuticoRESUMO
Treatment with cytosine arabinoside given intraperitoneally (ip) every 3 hours for 24 hours on every fourth day (Q3h/24h/4d) from 1 day after ip implantation of 10(6) or 10(7) leukemia L1210 cells in mice, was not observed to be superior to the same treatment after implantation of 10(5) cells. Similarly, when cytosine arabinoside therapy was delayed until Day 5 after 10(5) tumor cells were implanted, treatment Q3h/24h/4d did not provide a therapeutic advantage over treatment with a single injection every second or fourth day. A single treatment of the advanced disease with cyclophosphamide did not restore the sensitivity of the disease to the Q3h/24h/4d treatment schedule. Whether treatment with cytosine arabinoside was started on Days 1, 3, or 5, the optimal total dose per day for treatment given once every fourth day was 12-20 times greater than the optimal total dose per day for treatment given in eight equal injections every fourth day. Via the oral route, the Q3h/24h/4d treatment regimen was not superior to one treatment every fourth day from Day 1. The data clearly show that when the initial inoculum is high (10(6) or 10(7) cells) or when the disease is advanced, the response to cytosine arabinoside therapy does not display treatment-schedule dependency for the Q3h/24h/4d schedule.