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1.
Int J Environ Sci Technol (Tehran) ; 20(2): 2099-2110, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-35464816

RESUMEN

Many countries, including South Korea, focus on securing renewable energy technologies to cope with climate change and foster new industries. This study analyzed R&D performance and relevant factors through tracking data on the Korean government's renewable energy R&D project, which ended in 2010-2014. The main findings provide several meaningful information. First, the overall performance of completed projects is relatively low, both innovation and economic perspectives. Second, renewable energy source, R&D organizer, and The R&D stage are relevant factors on R&D performance. The R&D stage significantly influences innovation performance. Lastly, R&D performance is under an imbalance between innovation and economic perspectives. This paper can provide useful information to policy and decision-makers to improve future R&D project performance. In addition, scholars also may refer to related researches. Ultimately, we expect to promote renewable energy R&D projects and help manage their performance.

2.
J Appl Microbiol ; 131(3): 1226-1239, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-33590587

RESUMEN

AIMS: The objective of this study was to isolate a bacteriocin-producing strain and to characterize the expressed bacteriocin for the control of Listeria monocytogenes with aim of biopreservation application. METHODS AND RESULTS: Soil samples from a Korean organic farm were subjected to microbiological analysis for isolation of potential bacteriocinogenic LAB, based on a three-level approach, using L. monocytogenes ATCC 15313 as an indicator test micro-organism. From a total of 17 isolates with inhibitory potential, seven were confirmed to be bacteriocin producers. The selected isolates were differentiated based on their morphology, catalase reaction, sugar fermentation profile obtained by API50CHL and by RAPD-PCR generating two unique profiles. One of the isolates, ST110LD, a specific strong producer of anti-Listeria bacteriocins (12 800 AU ml-1 ) was identified as Leuconostoc citreum. The proteinaceous nature of the inhibitory compound produced by Leuc. citreum ST110LD was confirmed through treatment with pepsin and α-chymotrypsin. Bacteriocin activity was observed to be not affected by the presence of milk, NaCl, SDS, Tween 80 or glycerol. Bacteriocin ST110LD effectively inhibited the growth of exponentially growing L. monocytogenes ATCC 15313 during a 10-h incubation period in BHI at 37°C. In addition, this bacteriocin showed specific inhibition of only Listeria spp., but did not inhibit the growth of beneficial cultures included in the microbial test panel for assessment of the spectrum of activity. CONCLUSIONS: Leuconostoc citreum ST110LD was evaluated as safe bacterium strain, producing bacteriocin with high specificity against listerial and enterococcal species. Specificity of producer strain and expressed bacteriocin can be explored in biopreservation of different fermented food products or applied in biotherapy of antibiotic resistant listerial or enterococcal infections. SIGNIFICANCE AND IMPACT OF THE STUDY: To the best of our knowledge, this is the first report of bacteriocin produced by Leuc. citreum strain with highly specific antimicrobial activity against Listeria sp. and Enterococcus sp.


Asunto(s)
Bacteriocinas , Leuconostoc/química , Listeria monocytogenes , Bacteriocinas/farmacología , Granjas , Alimentos Fermentados , Contaminación de Alimentos/prevención & control , Microbiología de Alimentos , Listeria monocytogenes/efectos de los fármacos , Agricultura Orgánica , Técnica del ADN Polimorfo Amplificado Aleatorio , Microbiología del Suelo
3.
Ann Oncol ; 28(4): 791-797, 2017 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-28039177

RESUMEN

Background: Anaplastic lymphoma kinase (ALK) inhibition using crizotinib has become the standard of care in advanced ALK-rearranged non-small cell lung cancer (NSCLC), but the treatment outcomes and duration of response vary widely. Echinoderm microtubule-associated protein-like 4 (EML4)-ALK is the most common translocation, and the fusion variants show different sensitivity to crizotinib in vitro. However, there are only limited data on the specific EML4-ALK variants and clinical responses of patients to various ALK inhibitors. Patients and methods: By multiplex reverse-transcriptase PCR, which detects 12 variants of known EML4-ALK rearrangements, we retrospectively determined ALK fusion variants in 54 advanced ALK rearrangement-positive NSCLCs. We subdivided the patients into two groups (variants 1/2/others and variants 3a/b) by protein stability and evaluated correlations of the variant status with clinical responses to crizotinib, alectinib, or ceritinib. Moreover, we established the EML4-ALK variant-expressing system and analyzed patterns of sensitivity of the variants to ALK inhibitors. Results: Of the 54 tumors analyzed, EML4-ALK variants 3a/b (44.4%) was the most common type, followed by variants 1 (33.3%) and 2 (11.1%). The 2-year progression-free survival (PFS) rate was 76.0% [95% confidence interval (CI) 56.8-100] in group EML4-ALK variants 1/2/others versus 26.4% (95% CI 10.5-66.6) in group variants 3a/b (P = 0.034) among crizotinib-treated patients. Meanwhile, the 2-year PFS rate was 69.0% (95% CI 49.9-95.4) in group variants 1/2/others versus 32.7% (95% CI 15.6-68.4) in group variants 3a/b (P = 0.108) among all crizotinib-, alectinib-, and ceritinib-treated patients. Variant 3a- or 5a-harboring cells were resistant to ALK inhibitors with >10-fold higher half maximal inhibitory concentration in vitro. Conclusion: Our findings show that group EML4-ALK variants 3a/b may be a major source of ALK inhibitor resistance in the clinic. The variant-specific genotype of the EML4-ALK fusion allows for more precise stratification of patients with advanced NSCLC.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Resistencia a Antineoplásicos/genética , Neoplasias Pulmonares/genética , Proteínas de Fusión Oncogénica/genética , Adulto , Anciano , Antineoplásicos/uso terapéutico , Carbazoles/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Crizotinib , Supervivencia sin Enfermedad , Femenino , Genotipo , Humanos , Hibridación Fluorescente in Situ , Estimación de Kaplan-Meier , Neoplasias Pulmonares/tratamiento farmacológico , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa Multiplex , Piperidinas/uso terapéutico , Inhibidores de Proteínas Quinasas/uso terapéutico , Estabilidad Proteica , Pirazoles/uso terapéutico , Piridinas/uso terapéutico , Pirimidinas/uso terapéutico , Estudios Retrospectivos , Sulfonas/uso terapéutico
4.
J Hand Ther ; 28(4): 389-94; quiz 395, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26227308

RESUMEN

OBJECTIVES: To investigate the test-retest reliability of JTT in older patients with Parkinson's disease (PD); and to compare the Jebsen Taylor Hand Function Test (JTT) scores between PD and healthy subjects. STUDY DESIGN: Cross-sectional comparative study. METHODS: Fifteen PD and fifteen healthy subjects performed the JTT and the time taken to complete the JTT was recorded. RESULTS: Test-retest reliabilities of JTT subtests and total score of both dominant and non-dominant hand were good to excellent (ICCs = 0.77-0.97) except J5 checkers which had moderate reliability. PD subjects required significantly longer time to finish subtests and the whole JTT (p < 0.05), except the subtest J1 writing of dominant hand that showed marginal significance (p = 0.059). CONCLUSION: JTT is a reliable and easily available assessment tool for assessing the hand function of PD subjects. PD subjects took a longer time to complete the JTT, suggesting that they have deficits in gross and fine functional dexterity.


Asunto(s)
Evaluación de la Discapacidad , Mano/fisiopatología , Destreza Motora/fisiología , Enfermedad de Parkinson/fisiopatología , Estudios de Casos y Controles , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados
6.
Artículo en Inglés | MEDLINE | ID: mdl-37327667

RESUMEN

Considerable costs are associated with infertility treatment, but little evidence is available on the main drivers of treatment costs. This cost analysis investigated key costs for treatment with assisted reproductive technology (ART) and the proportion of costs attributed to the acquisition of recombinant human follicle-stimulating hormone (r-hFSH) alfa originator for one fresh embryo transfer (ET) leading to a live birth in Spain, Norway, the UK, Germany, Denmark, South Korea, Australia, and New Zealand. The total costs for one ART cycle with a fresh ET leading to a live birth varied between countries (€4108-€12,314). Costs for pregnancy and live birth were the major contributors in European countries, and the costs of oocyte retrieval, monitoring during ovarian stimulation, pregnancy, and live birth were the top contributors in the Asia-Pacific countries, included in this analysis. Acquisition costs for r-hFSH alfa originator contributed to only 5%-17% of the total costs of one ART cycle with one fresh ET leading to a live birth.


Asunto(s)
Hormona Folículo Estimulante Humana , Nacimiento Vivo , Embarazo , Femenino , Humanos , Embarazo Múltiple , Fertilidad , Inducción de la Ovulación , Costos y Análisis de Costo , Índice de Embarazo , Fertilización In Vitro
8.
Clin Exp Allergy ; 42(8): 1197-205, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22805467

RESUMEN

BACKGROUND: In Westernized countries, over 1% of the population is allergic to peanuts or tree nuts, which carries a risk of severe allergic reactions. Several studies support the efficacy of peanut oral immunotherapy (OIT) for reducing the clinical sensitivity of affected individuals; however, the mechanisms of this effect are still being characterized. One mechanism that may contribute is the suppression of effector cells, such as basophils. Basophil anergy has been characterized in vitro as a pathway-specific hyporesponsiveness; however, this has not been demonstrated to occur in vivo. OBJECTIVE: To evaluate the hypothesis that basophil anergy occurs in vivo due to chronic allergen exposure in the setting of a clinical oral immunotherapy trial. METHODS: Samples of peripheral blood were obtained from subjects during a placebo-controlled clinical trial of peanut OIT. Basophil reactivity to in vitro stimulation with peanut allergen and controls was assessed by the upregulation of activation markers, CD63 and CD203c, measured by flow cytometry. RESULTS: The upregulation of CD63 following stimulation of the IgE receptor, either specifically with peanut allergen or non-specifically with anti-IgE antibody, was strongly suppressed by active OIT. However, OIT did not significantly suppress this response in basophils stimulated by the distinct fMLP receptor pathway. In the subset of subjects with egg sensitization, active peanut OIT also suppressed CD63 upregulation in response to stimulation with egg allergen. Allergen OIT also suppressed the upregulation of CD203c including in response to stimulation with IL-3 alone. CONCLUSION: Peanut OIT induces a hyporesponsive state in basophils that is consistent with pathway-specific anergy previously described in vitro. This suggests the hypothesis that effector cell anergy could contribute to clinical desensitization.


Asunto(s)
Alérgenos/inmunología , Arachis/inmunología , Basófilos/inmunología , Desensibilización Inmunológica , Hipersensibilidad al Cacahuete/inmunología , Transducción de Señal , Administración Oral , Alérgenos/administración & dosificación , Basófilos/metabolismo , Niño , Preescolar , Humanos , Tolerancia Inmunológica , Hipersensibilidad al Cacahuete/metabolismo , Hipersensibilidad al Cacahuete/terapia , Hidrolasas Diéster Fosfóricas/metabolismo , Pirofosfatasas/metabolismo , Receptores de IgE/inmunología , Tetraspanina 30/metabolismo
10.
J Health Care Poor Underserved ; 33(2): 950-972, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35574887

RESUMEN

HIV stigma in health care disrupts the care continuum and negatively affects health outcomes among people living with HIV. Few studies explore HIV stigma from the perspective of health care providers, which was the aim of this mixed-methods, community-based participatory research study. Guided by the Health Stigma Discrimination Framework, we conducted an online survey and focus group interviews with 88 and 18 participants. Data were mixed during interpretation and reporting results. Stigma was low overall and participants reported more stigma among their colleagues. The main drivers of stigma included lack of knowledge and fear. Workplace policies and culture were key stigma facilitators. Stigma manifested highest through the endorsement of stereotypes and in the use of unnecessary precautions when treating people with HIV. This study adds to our understanding of HIV stigma within health care settings, with implications for the development of multi-level interventions to reduce HIV stigma among health care professionals.


Asunto(s)
Investigación Participativa Basada en la Comunidad , Infecciones por VIH , Grupos Focales , Personal de Salud , Humanos , Estigma Social
11.
Allergol Immunopathol (Madr) ; 39(5): 291-4, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21272988

RESUMEN

BACKGROUND: Studies on serum IgE levels during pregnancy are limited. OBJECTIVE: To investigate the course of serum total IgE levels during pregnancy and postpartum. METHODS: 159 pregnant subjects provided 218 serum samples during various stages of pregnancy and the postpartum period. Serum total IgE geometric means were compared at various trimesters and postpartum. In addition, the postpartum IgE data were analysed according to the method of delivery. Analysis was also done according to history of allergy. RESULTS: The geometric mean serum total IgE was 20.5 IU/ml in the first trimester, 20.8 IU/ml in the second and 22.2 IU/ml in the third. Postpartum serum IgE level showed a lower mean, 14.9 IU/ml during the early postpartum period (less than 30 days) compared to 30.3 IU/ml during the late postpartum period (30 days-25 weeks). However this was not statistically significant. Serum IgE in the postpartum period also did not differ according to method of delivery. A history of allergy was positive in 98 samples, negative in 61 and unclear in 59. Using analysis of variance, none of these three groups showed significant change in serum total IgE level during pregnancy or postpartum. CONCLUSION: In this cross-sectional study, serum total IgE levels showed no statistically significant changes during pregnancy or postpartum. This finding would be of greater weight if reproduced in a larger number of subjects with multiple serial samples at fixed regular time intervals during pregnancy and postpartum.


Asunto(s)
Inmunoglobulina E/sangre , Periodo Posparto/sangre , Complicaciones del Embarazo/sangre , Adolescente , Adulto , Estudios Transversales , Parto Obstétrico , Femenino , Humanos , Periodo Posparto/inmunología , Embarazo , Complicaciones del Embarazo/inmunología , Trimestres del Embarazo , Adulto Joven
12.
Eur J Cancer ; 151: 190-200, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34010788

RESUMEN

BACKGROUND: Adding ovarian function suppression (OFS) after chemotherapy improves survival in young women with moderate- and high-risk breast cancer. Assessment of ovarian function restoration after chemotherapy becomes critical for subsequent endocrine treatment and addressing fertility issues. PATIENTS AND METHODS: In the adding OFS after chemotherapy trial, patients who resumed ovarian function up to 2 years after chemotherapy were randomised to receive either 5 years of tamoxifen or adding 2 years of OFS with tamoxifen. Ovarian function was evaluated from enrolment to randomisation, and patients who did not randomise because of amenorrhoea for 2 years received tamoxifen and were followed up for 5 years. Prospectively collected consecutive hormone levels (proportion of patients with premenopausal follicle-stimulating hormone [FSH] levels <30 mIU/mL and oestradiol [E2] levels ≥40 pg/mL) and history of menstruation were available for 1067 patients with breast cancer. RESULTS: Over 5 years of tamoxifen treatment, 69% of patients resumed menstruation and 98% and 74% of patients satisfied predefined ovarian function restoration as per serum FSH and E2 levels, respectively. Menstruation was restored in 91% of patients younger than 35 years at baseline, but in only 33% of 45-year-old patients over 5 years. Among these patients, 41% experienced menstruation restoration within 2 years after chemotherapy and 28% slowly restored menstruation after 2-5 years. Younger age (<35 years) at baseline, anthracycline without taxanes and ≤90 days of chemotherapy were predictors of menstruation restoration. CONCLUSIONS: During 5 years of tamoxifen treatment after chemotherapy, two-thirds of the patients experienced menstruation restoration, especially patients younger than 35 years. Young age, Adriamycin without taxanes and short duration of chemotherapy appeared to have a positive effect on ovarian reserves in the long term. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00912548.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/tratamiento farmacológico , Menstruación/efectos de los fármacos , Ovario/efectos de los fármacos , Premenopausia , Tamoxifeno/uso terapéutico , Adulto , Factores de Edad , Antineoplásicos Hormonales/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Biomarcadores/sangre , Estradiol/sangre , Femenino , Hormona Folículo Estimulante Humana/sangre , Humanos , Menstruación/sangre , Persona de Mediana Edad , Ovario/metabolismo , Ovario/fisiopatología , Recuperación de la Función , República de Corea , Medición de Riesgo , Factores de Riesgo , Tamoxifeno/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
13.
J Nanosci Nanotechnol ; 10(5): 3416-9, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20358969

RESUMEN

LiFePO4/Carbon nanocomposites with varying amounts of carbon were synthesized using polyol process without any further heating as a post step. The X-ray diffraction patterns of all samples were indexed on the basis of orthorhombic olivine-type structure. The field emission-TEM images of composites with the amount of 3 approximately 15 wt% carbon showed the average sizes of 45 approximately 80 nm with nanorod shape surrounded by carbon. The initial discharge curves of LiFePO4/Carbon show 166, 157, 142, and 119 mAh/g capacities at a current density of 0.1 mA/cm2 in the voltage range of 2.5-4.2 V, respectively, without capacity fading and excellent cycle retentions during the 20 cycles. Especially, the sample of amount of 3 wt% carbon shows the excellent high rate performances at 15 and 30 C rates with high capacity retention compared with previously reported results of high temperature processed results, due to the existence of conductive agents such as carbon which suppresses particle growth and exhibits improved electronic conductivity and lithium ion diffusivity, simultaneously.

14.
J Nanosci Nanotechnol ; 10(5): 3357-61, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20358956

RESUMEN

Olivine structured LiMPO4 (M = Fe, Mn, Co) was synthesized by the solvothermal process using a polyol medium of diethylene glycol (DEG) without any further heating as a post procedure. The synthesized LiMPO4 nanoparticles exhibited an average length of 200 approximately 400 nm, width of 200 approximately 300 nm, and thickness of 20 approximately 50 nm, and with well dispersed plate and rod morphologies. The Rietveld-refined X-ray diffraction (XRD) pattern of LiFePO4 exhibited a good fit with an olivine structure (space group: Pnma) and no undesirable impurity phases. The LiFePO4 nanocrystals showed a reversible capacity of 167 mAh/g, equating to a utilization efficiency of 98% of its theoretical capacity, with a good cyclability over an extended range up to 40 cycles.

15.
Anaesthesia ; 70(9): 1101-2, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26263870
16.
Phys Rev E ; 101(5-1): 053207, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-32575181

RESUMEN

We studied parallel propagating electromagnetic waves in a magnetized quantum electron plasma of finite temperature, as an extension of our previous study on a zero temperature plasma. We obtained simple analytic dispersion relations in the long wavelength limit that included the thermal effect as correction terms to the zero temperature results. As in the zero temperature case, the lower branch of the R wave showed significant damping and became ill-defined at short wavelengths. Quantum effects seemed to give qualitative changes, such as the appearance of anomalous dispersion regions, to the classical dispersion relations when v_{F}/v_{th}≤0.2 for a set of exemplary parameters of v_{F}=0.1c and ω_{ce}/ω_{pe}=0.05 was used. We also noted that introduction of the Planck constant in the quantum Vlasov equation changed the shape of the anomalous dispersion region qualitatively, by forming a normal dispersion region in the middle of the original single broad anomalous dispersion region.

17.
J Cell Biol ; 105(2): 705-11, 1987 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-3114267

RESUMEN

Carbon tetrachloride (CCl4) treatment of rats produces an early defect in methylation of hepatocyte ribosomal RNA, which occurs concurrently with a defect in the protein synthetic capacity of isolated ribosomes. The CCl4-induced methylation defect is specific for the 2'-O-ribose position, and a corresponding proportional increase in m7G base methylation occurs in vivo. Undermethylated ribosomal subunits (rRNA) from CCl4-treated preparations can be methylated in vitro to a much greater extent than those from control preparations, and in vitro methylation restores their functional capacity. In vitro methylation of treated ribosomal subunits (which restores functional capacity) occurs at 2'-O-ribose positions (largely G residues). In contrast, in vitro methylation of control ribosomal subunits (which does not affect functional activity) represents base methylation as m7G, sites which are apparently methylated in treated preparations in vivo. Methylation/demethylation of 2'-O-ribose sites in rRNA exposed on the surface of cytoplasmic ribosomal subunits may represent an important cellular mechanism for controlling protein synthesis in quiescent hepatocytes, and it appears that CCl4 disrupts protein synthesis by inhibiting this 2'-O-ribose methylation.


Asunto(s)
Intoxicación por Tetracloruro de Carbono/metabolismo , Hígado/metabolismo , Biosíntesis de Proteínas/efectos de los fármacos , ARN Ribosómico/efectos de los fármacos , Animales , Tetracloruro de Carbono/farmacología , Citoplasma/efectos de los fármacos , Citoplasma/metabolismo , Hígado/efectos de los fármacos , Masculino , Metilación , ARN Ribosómico/genética , Ratas , Ratas Endogámicas , Ribosa
18.
Science ; 199(4336): 1431-3, 1978 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-17796675

RESUMEN

Phosphorite concretions have been detected in the kidneys of two widespread species of mollusks, Mercenaria mercenaria and Argopecten irradians, which have relatively high population densities. These concretions are the first documentation of the direct biogenic formation of phosphorite grains. The concretions are principally amorphous calcium phosphate, which upon being heated yields an x-ray diffraction pattern which is essentially that of chlorapatite. These concretions appear to be a normal formation of the excretory process of mollusks under reproductive, environmental, or pollutant-induced stress. Biogenic production of phosphorite concretions over long periods of time and diagenetic change from amorphous to crystalline structure, coupled with secondary enrichment, may account for the formation of some marine phosphorite desposits which are not easily explained by the chemical precipitation-replacement hypothesis.

19.
Science ; 167(3918): 648-50, 1970 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-17781530

RESUMEN

The lunar soil collected by Apollo 11 consists primarily of submillimeter material and is finer in grain size than soil previously recorded photographically by Surveyor experiments. The main constituents are fine-grained to glassy rocks of basaltic affinity and coherent breccia of undetermined origin. Dark glass, containing abundant nickel-iron spheres, coats many rocks, mineral, and breccia fragments. Several types of homogeneous glass occur as fragments and spheres. Colorless spheres, probably an exotic component, are abundant in the fraction finer than 20 microns.

20.
Nanotechnology ; 20(7): 075401, 2009 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-19417419

RESUMEN

The effect of an applied mechanical stress on the tunneling conductance of a ferroelectric tunnel barrier between substrates and dissimilar electrodes is studied. Using a thermodynamic model and taking into account polarization charge screening in the electrodes and the near-surface inhomogeneous polarization distribution, the tunneling conductance is calculated as a function of the applied stress. It is found that reversing an applied stress can also change the tunnel barrier sufficiently to produce an effect similar to the giant electro-resistance one due to polarization reversal, which is particularly significant near the stress-dependent paraelectric/ferroelectric phase transition. Indeed, the sensitivity is adequate for high-sensitivity electronic and mechanical sensors, memories and other nanodevices.

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