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1.
Phys Rev Lett ; 130(14): 146101, 2023 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-37084444

RESUMEN

Because of the half-filled t_{2g}-electron configuration, the BO_{6} octahedral distortion in a 3d^{3} perovskite system is usually very limited. In this Letter, a perovskitelike oxide Hg_{0.75}Pb_{0.25}MnO_{3} (HPMO) with a 3d^{3} Mn^{4+} state was synthesized by using high pressure and high temperature methods. This compound exhibits an unusually large octahedral distortion enhanced by approximately 2 orders of magnitude compared with that observed in other 3d^{3} perovskite systems like RCr^{3+}O_{3} (R=rare earth). Essentially different from centrosymmetric HgMnO_{3} and PbMnO_{3}, the A-site doped HPMO presents a polar crystal structure with the space group Ama2 and a substantial spontaneous electric polarization (26.5 µC/cm^{2} in theory) arising from the off-center displacements of A- and B-site ions. More interestingly, a prominent net photocurrent and switchable photovoltaic effect with a sustainable photoresponse were observed in the current polycrystalline HPMO. This Letter provides an exceptional d^{3} material system which shows unusually large octahedral distortion and displacement-type ferroelectricity violating the "d^{0}-ness" rule.

2.
Proc Natl Acad Sci U S A ; 116(25): 12156-12160, 2019 Jun 18.
Artículo en Inglés | MEDLINE | ID: mdl-31109998

RESUMEN

The mechanism of superconductivity in cuprates remains one of the big challenges of condensed matter physics. High-T c cuprates crystallize into a layered perovskite structure featuring copper oxygen octahedral coordination. Due to the Jahn Teller effect in combination with the strong static Coulomb interaction, the octahedra in high-T c cuprates are elongated along the c axis, leading to a 3dx 2-y 2 orbital at the top of the band structure wherein the doped holes reside. This scenario gives rise to 2D characteristics in high-T c cuprates that favor d-wave pairing symmetry. Here, we report superconductivity in a cuprate Ba2CuO4-y , wherein the local octahedron is in a very exceptional compressed version. The Ba2CuO4-y compound was synthesized at high pressure at high temperatures and shows bulk superconductivity with critical temperature (T c ) above 70 K at ambient conditions. This superconducting transition temperature is more than 30 K higher than the T c for the isostructural counterparts based on classical La2CuO4 X-ray absorption measurements indicate the heavily doped nature of the Ba2CuO4-y superconductor. In compressed octahedron, the 3d3z 2-r 2 orbital will be lifted above the 3dx 2-y 2 orbital, leading to significant 3D nature in addition to the conventional 3dx 2-y 2 orbital. This work sheds important light on advancing our comprehensive understanding of the superconducting mechanism of high T c in cuprate materials.

3.
Zhonghua Nei Ke Za Zhi ; 61(2): 193-199, 2022 Feb 01.
Artículo en Zh | MEDLINE | ID: mdl-35090255

RESUMEN

Objective: To investigate the characteristics of functional limitation and associated factors in patients with rheumatoid arthritis (RA). Methods: Consecutive patients with RA were recruited from August 2015 to June 2019 at Department of Rheumatology, Sun Yat-Sen Memorial Hospital. Demographic and clinical characteristics including age, gender, erythrocyte sedimentation rate (ESR), visual analogue scale (VAS) of pain, clinical disease activity index (CDAI), modified total Sharp score were collected. Physical function was assessed by the Stanford health assessment questionnaire disability index (HAQ-DI).Ordered logistic regression was used to analyze the related factors of HAQ-DI. Results: A total of 643 RA patients were finally recruited including 114 males and 529 females with mean age (49.7±12.9) years. There were 399 (62.1%) patients having different degrees of functional limitation, who were classified as mild (293, 45.6%), moderate (73, 11.4%) and severe (33, 5.1%). The prevalence of functional limitation was positively correlated with age and disease activity. The most restricted activity was walking [43.5% (280/643)], followed by gripping [36.1% (232/643)], reaching [35.5% (228/643)], daily activities [33.4% (215/643)], hygiene [33.0% (212/643)], dressing and grooming [29.7% (191/643)] and arising [29.1% (187/643)], and the last eating [18.4% (118/643)]. Multivariate ordered logistic regression analysis showed that age (OR=1.019, 95%CI 1.004-1.035),pain VAS (OR=1.820, 95%CI 1.616-2.050), ESR (OR=1.009, 95%CI 1.001-1.017), CDAI (OR=1.080, 95%CI 1.059-1.102) and modified total Sharp score (OR=1.010, 95%CI 1.004-1.015) were associated factors of functional limitation. Conclusion: The majority RA patients have functional limitation. Age, pain and active disease are independent associated factors. Therefore, target treatment and control of pain should be emphasized in RA patients.


Asunto(s)
Artritis Reumatoide , Adulto , Sedimentación Sanguínea , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Dolor , Encuestas y Cuestionarios
4.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(3): 397-400, 2022 Mar 06.
Artículo en Zh | MEDLINE | ID: mdl-35381666

RESUMEN

This study analyzed the characteristics and change trend of Guangzhou citizens' demands related to vaccination through government hotlines 12345 and 12320 from 2018 to 2020. It understood the hotspots and needs of the public for vaccination work, analyzed the problems existing in vaccination work, and provided reference and suggestions for health departments to improve vaccination services and formulate relevant policies: to timely improve the professional ability and knowledge reserve of hotline personnel; to strengthen the construction of vaccination service system;to optimize the appointment vaccination service application; to scientifically purchase HPV vaccine and ensure the production and supply of vaccine.


Asunto(s)
Líneas Directas , Vacunas contra Papillomavirus , Gobierno , Humanos , Vacunación
5.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(12): 1880-1888, 2022 Dec 06.
Artículo en Zh | MEDLINE | ID: mdl-36536582

RESUMEN

Gene fusion is one of the mechanisms that promote tumor development. It is also an important cause for the poor prognosis of patients. The detection of gene fusion is crucial for the recognition of tumor biomarker, cancer subtype classification, and clinical medication guidance. Appropriate methods can help the early diagnosis and avoid ineffective medication. Traditional tests include fluorescence in situ hybridization (FISH), immunohistochemistry (IHC), reverse transcription of PCR (RT-PCR), and next generation sequencing (NGS). The next generation sequencing (NGS) mainly includes: whole genome sequencing (WGS), whole transcriptome sequencing (WTS) and target sequencing (hybridization capture method/amplicon method). In clinical concomitant diagnostic applications, some factors such as operability, time/money costs, and the level of expertise required for data analysis should be considered. This article concludes with a discussion of the technical principles of different detection methods and advantages/limitations. Meanwhile, it provides reference opinions for the detection methods of gene fusion.


Asunto(s)
Neoplasias Pulmonares , Neoplasias , Humanos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Hibridación Fluorescente in Situ , Neoplasias/genética , Fusión Génica , Tecnología , Neoplasias Pulmonares/diagnóstico
6.
Zhonghua Yu Fang Yi Xue Za Zhi ; 56(5): 574-582, 2022 May 06.
Artículo en Zh | MEDLINE | ID: mdl-35644970

RESUMEN

Objective: To investigate the characteristics of non-alcoholic fatty liver disease (NAFLD) and its associated factors in rheumatoid arthritis (RA) patients. Methods: This cross-sectional study recruited 385 RA patients [including 72 (18.7%) male and 313 (81.3%) female] who received abdominal sonographic examination from August 2015 to May 2021 at Department of Rheumatology, Sun Yat-Sen Memorial Hospital. There were 28 RA patients at 16-29 years old and 32, 80, 121, 99, 25 at 30-39, 40-49, 50-59, 60-69, ≥ 70 years old, respectively. Demographic and clinical data were collected including age, gender, history of alcohol consumption, disease duration, body mass index (BMI), waist circumference, blood pressure, RA disease activity indicators and previous medications. Logistic regression analyses were used to identify the associated factors of NAFLD in RA patients. Results: The prevalence of NAFLD was 24.2% (93/385) in RA patients, 26.3% (21/80) in 40-49 age group and 33.1% (40/121) in 50-59 age group. There were 22.1% (85/385) and 3.6% (14/385) RA patients with overweight and obese, in which the prevalence of NAFLD was 45.9% (39/85) and 78.6% (11/14) respectively, which was 2.6 folds and 4.5 folds that of RA patients with normal BMI. Although there was no significant difference of age, gender and RA disease activity indicators between RA patients with or without NAFLD, those with NAFLD had higher proportions of metabolic diseases including obese (11.8% vs. 1.0%), central obesity (47.3% vs. 16.8%), hypertension (45.2% vs. 29.8%) and type 2 diabetes mellitus (24.7% vs. 12.0%), consistent with higher levels of total cholesterol [(5.33±1.31) mmol/L vs. (4.73±1.12) mmol/L], triglyceride [(1.51±1.08) mmol/L vs. (0.98±0.54) mmol/L] and low-density lipoprotein cholesterol [(3.37±0.97) mmol/L vs. (2.97±0.78) mmol/L, all P<0.05]. Multivariate logistic regression analysis showed that BMI (OR=1.314) and triglyceride (OR=1.809) were the independent factors positively associated with NAFLD in RA patients. Conclusion: NAFLD is a common comorbidity in RA patients, especially in those with middle-aged, overweight or obese, which is associated with high BMI or high triglyceride. Screening and management of NAFLD in RA patients especially those with overweight, obese or dyslipidemia should be emphasized.


Asunto(s)
Artritis Reumatoide , Enfermedad del Hígado Graso no Alcohólico , Adolescente , Adulto , Anciano , Artritis Reumatoide/complicaciones , Artritis Reumatoide/epidemiología , LDL-Colesterol , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Enfermedad del Hígado Graso no Alcohólico/epidemiología , Obesidad/complicaciones , Obesidad/epidemiología , Sobrepeso/complicaciones , Sobrepeso/epidemiología , Triglicéridos , Adulto Joven
7.
J Synchrotron Radiat ; 28(Pt 3): 977-986, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33950006

RESUMEN

We report on the development of a high-resolution and highly efficient beamline for soft X-ray resonant inelastic X-ray scattering (RIXS) located at the Taiwan Photon Source. This beamline adopts an optical design that uses an active grating monochromator (AGM) and an active grating spectrometer (AGS) to implement the energy compensation principle of grating dispersion. Active gratings are utilized to diminish defocus, coma and higher-order aberrations, as well as to decrease the slope errors caused by thermal deformation and optical polishing. The AGS is mounted on a rotatable granite platform to enable momentum-resolved RIXS measurements with scattering angles over a wide range. Several high-precision instruments developed in-house for this beamline are described briefly. The best energy resolution obtained from this AGM-AGS beamline was 12.4 meV at 530 eV, achieving a resolving power of 4.2 × 104, while the bandwidth of the incident soft X-rays was kept at 0.5 eV. To demonstrate the scientific impact of high-resolution RIXS, we present an example of momentum-resolved RIXS measurements on a high-temperature superconducting cuprate, i.e. La2-xSrxCuO4. The measurements reveal the A1g buckling phonons in superconducting cuprates, opening a new opportunity to investigate the coupling between these phonons and charge-density waves.

8.
Scand J Rheumatol ; 50(4): 280-289, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33554691

RESUMEN

Objective: Little is known about muscle wasting in elderly patients with rheumatoid arthritis (RA). We examined muscle characteristics and their clinical significance in this group.Method: Consecutive RA patients were recruited and clinical data were collected. Muscle mass and distribution were assessed using bioelectric impedance analysis. Myopenia was defined as an appendicular skeletal muscle mass index (ASMI) ≤ 7.0 kg/m2 (men) and ≤ 5.7 kg/m2 (women).Results: Among the 643 RA patients recruited, 165 (25.7%) were elderly patients (age ≥ 60 years) with a mean age of 65.1 ± 4.5 years. Compared with young patients (age < 60 years), elderly RA patients had significantly higher Disease Activity Score based on 28-joint count-C-reactive protein (DAS28-CRP) (median 3.4 vs 3.2), Health Assessment Questionnaire Disability Index (HAQ-DI) (0.38 vs 0.13), and modified total Sharp score (mTSS) (16 vs 9), and a higher proportion of myopenia (54.5% vs 41.4%; all p < 0.01). Elderly RA patients with myopenia (n = 90, 14.0%) had significantly higher DAS28-CRP (3.6 vs 3.0), HAQ-DI (0.50 vs 0.12), and mTSS (21 vs 7) than young RA patients without myopenia (n = 280, 43.5%; all p < 0.0083). Multivariate logistic and linear regression analyses showed that myopenia, high HAQ-DI, active smoking, hypertension, diabetes, and coronary atherosclerotic heart disease were the main relevant characteristics of elderly RA patients. Age positively correlated with HAQ-DI, and ASMI negatively correlated with HAQ-DI (both p < 0.01). Further mediation analysis showed that ASMI partially mediated the association between age and HAQ-DI.Conclusion: Our data reveal that half of elderly RA patients manifest myopenia which aggravates physical dysfunction as a mediator of age. Myopenia, a neglected complication in elderly RA patients, should be recognized and further investigated.


Asunto(s)
Artritis Reumatoide/complicaciones , Atrofia Muscular/etiología , Adulto , Anciano , Artritis Reumatoide/fisiopatología , Estudios Transversales , Evaluación de la Discapacidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Atrofia Muscular/fisiopatología
9.
Zhonghua Nei Ke Za Zhi ; 60(2): 128-133, 2021 Feb 01.
Artículo en Zh | MEDLINE | ID: mdl-33503723

RESUMEN

Objective: To investigate the value of baseline anti-mutated citrullinated vimentin (MCV) antibody for predicting one-year radiographic progression in patients with rheumatoid arthritis (RA). Methods: Consecutive RA patients were recruited from November 2014 to July 2018 at Department of Rheumatology, Sun Yat-sen Memorial Hospital, Clinical data were collected including disease activity score in 28 joints with four variables including C-reactive protein (CRP).Serum anti-MCV antibody at baseline was detected by enzyme-linked immunosorbent assay. X ray assessment of both hands/wrists was performed and assessed according to the Sharp/van der Heijde modified score (mTSS) at baseline and the 12th month. Univariate and multivariate logistic regression analyses were used to identify the risk factors for one-year radiographic progression. Results: Among 220 RA patients recruited, the positive rate of anti-MCV antibody at baseline was 77.7%. Compared with those with negative anti-MCV antibody, RA patients with positive anti-MCV antibody had higher disease activity score in 28 joints with four variables induding CRP [3.8 (2.4, 5.0) vs. 3.1 (2.1, 4.0), P=0.007], more physical dysfunction (21.6% vs. 8.2%, P=0.033) and higher radiographic indicators including mTSS [11 (2, 27) vs. 4 (1, 10), P=0.003], joint space narrowing [JSN, 4 (0, 14) vs. 2 (0, 6), P=0.024] and joint erosion[JE, 5 (1, 18)vs. 3 (0, 5), P=0.003]. After one-year follow-up, sixty-six RA patients (30.0%) developed radiographic progression, the percentage of whom was significantly higher in positive anti-MCV group than that in negative anti-MCV group (33.9% vs.16.3%, P=0.018). Multivariate logistic regression analysis suggested that positive anti-MCV antibody at baseline was an independent risk factor for one-year radiographic progression (OR=2.341, 95%CI 1.002-5.469). Conclusion: Positive anti-MCV antibody at baseline predicts one-year radiographic progression in RA patients. In the future, anti-MCV antibody can be used not only as a supplementary laboratory marker, but also in disease activity assessment and prognosis prediction for RA.


Asunto(s)
Artritis Reumatoide , Péptidos Cíclicos , Artritis Reumatoide/diagnóstico por imagen , Autoanticuerpos , Biomarcadores , Progresión de la Enfermedad , Humanos , Vimentina
10.
Br J Dermatol ; 180(3): 553-558, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30216411

RESUMEN

BACKGROUND: Bullous pemphigoid (BP) is the most common autoimmune bullous disease. Whether there is an increased risk for subsequent BP among patients with cancer is still unclear. OBJECTIVES: To evaluate the risk for subsequent BP in patients with cancer. METHODS: This nationwide population-based cohort study was based on data obtained from the Taiwan National Health Insurance Database between 2000 and 2011. A total of 36 838 patients with cancer and 147 352 age-, sex- and index-date-matched controls were recruited. The hazard ratio (HR) of subsequent BP in the patients with cancer was analysed using a Fine-Gray competing risk regression model with mortality as the competing event. RESULTS: The incidence of BP per 100 000 person-years was 17·2 in the patients with cancer and 19·8 in the controls; therefore, the crude incidence rate ratio was 0·87 [95% confidence interval (CI) 0·53-1·36]. The HR of subsequent BP in the patients with cancer was 0·47 (95% CI 0·23-0·94) using the Fine-Gray competing risk regression model. Age (HR 1·05, 95% CI 1·03-1·07), diabetes mellitus (HR 1·69, 95% CI 1·10-2·59) and cerebrovascular disease (HR 2·14, 95% CI 1·36-3·34) were independent risk factors for BP. CONCLUSIONS: The incidence of BP in patients with cancer was not higher than in the control group. Cancer is not a risk factor for BP.


Asunto(s)
Neoplasias/epidemiología , Penfigoide Ampolloso/epidemiología , Anciano , Bases de Datos Factuales/estadística & datos numéricos , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Neoplasias/complicaciones , Penfigoide Ampolloso/etiología , Estudios Retrospectivos , Medición de Riesgo , Factores de Riesgo , Taiwán/epidemiología
11.
Phys Rev Lett ; 119(19): 196402, 2017 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-29219525

RESUMEN

We carried out temperature-dependent (20-550 K) measurements of resonant inelastic x-ray scattering on LaCoO_{3} to investigate the evolution of its electronic structure across the spin-state crossover. In combination with charge-transfer multiplet calculations, we accurately quantified the renomalized crystal-field excitation energies and spin-state populations. We show that the screening of the effective on-site Coulomb interaction of 3d electrons is orbital selective and coupled to the spin-state crossover in LaCoO_{3}. The results establish that the gradual spin-state crossover is associated with a relative change of Coulomb energy versus bandwidth, leading to a Mott-type insulator-to-metal transition.

13.
Phys Rev Lett ; 117(14): 147401, 2016 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-27740843

RESUMEN

Resonant inelastic x-ray scattering is used to investigate the electronic origin of orbital polarization in nickelate heterostructures taking LaTiO_{3}-LaNiO_{3}-3×(LaAlO_{3}), a system with exceptionally large polarization, as a model system. We find that heterostructuring generates only minor changes in the Ni 3d orbital energy levels, contradicting the often-invoked picture in which changes in orbital energy levels generate orbital polarization. Instead, O K-edge x-ray absorption spectroscopy demonstrates that orbital polarization is caused by an anisotropic reconstruction of the oxygen ligand hole states. This provides an explanation for the limited success of theoretical predictions based on tuning orbital energy levels and implies that future theories should focus on anisotropic hybridization as the most effective means to drive large changes in electronic structure and realize novel emergent phenomena.

14.
Proc Natl Acad Sci U S A ; 109(27): E1815-9, 2012 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-22647607

RESUMEN

Widespread adoption of superconducting technologies awaits the discovery of new materials with enhanced properties, especially higher superconducting transition temperatures T(c). The unexpected discovery of high T(c) superconductivity in cuprates suggests that the highest T(c)s occur when pressure or doping transform the localized and moment-bearing electrons in antiferromagnetic insulators into itinerant carriers in a metal, where magnetism is preserved in the form of strong correlations. The absence of this transition in Fe-based superconductors may limit their T(c)s, but even larger T(c)s may be possible in their isostructural Mn analogs, which are antiferromagnetic insulators like the cuprates. It is generally believed that prohibitively large pressures would be required to suppress the effects of the strong Hund's rule coupling in these Mn-based compounds, collapsing the insulating gap and enabling superconductivity. Indeed, no Mn-based compounds are known to be superconductors. The electronic structure calculations and X-ray diffraction measurements presented here challenge these long held beliefs, finding that only modest pressures are required to transform LaMnPO, isostructural to superconducting host LaFeAsO, from an antiferromagnetic insulator to a metallic antiferromagnet, where the Mn moment vanishes in a second pressure-driven transition. Proximity to these charge and moment delocalization transitions in LaMnPO results in a highly correlated metallic state, the familiar breeding ground of superconductivity.


Asunto(s)
Hierro/química , Lantano/química , Magnetismo/métodos , Manganeso/química , Polonio/química , Conductividad Eléctrica , Impedancia Eléctrica , Electrones , Óptica y Fotónica/métodos , Presión , Temperatura
15.
J Synchrotron Radiat ; 21(Pt 2): 325-32, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24562553

RESUMEN

The design, construction and commissioning of a beamline and spectrometer for inelastic soft X-ray scattering at high resolution in a highly efficient system are presented. Based on the energy-compensation principle of grating dispersion, the design of the monochromator-spectrometer system greatly enhances the efficiency of measurement of inelastic soft X-rays scattering. Comprising two bendable gratings, the set-up effectively diminishes the defocus and coma aberrations. At commissioning, this system showed results of spin-flip, d-d and charge-transfer excitations of NiO. These results are consistent with published results but exhibit improved spectral resolution and increased efficiency of measurement. The best energy resolution of the set-up in terms of full width at half-maximum is 108 meV at an incident photon energy tuned about the Ni L3-edge.

16.
J Periodontal Res ; 49(6): 696-702, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24329929

RESUMEN

BACKGROUND AND OBJECTIVE: The study aimed to evaluate the effect of 0.25% sodium hypochlorite twice-weekly oral rinse on plaque and gingivitis in patients with minimally treated periodontitis. MATERIAL AND METHODS: The study included 30 patients with periodontitis, it lasted 3 mo, and it was performed as a randomized, controlled, single-blinded, clinical trial in parallel groups. Fifteen patients rinsed for 30 s with 15 mL of a fresh solution of 0.25% sodium hypochlorite (test) and 15 patients rinsed with 15 mL of water (control). Clorox(®) regular bleach was the source of the sodium hypochlorite. At baseline and at 2 wk, the study patients received professional subgingival irrigation for 5 min with either 0.25% sodium hypochlorite or water, but no subgingival or supragingival scaling. The presence or absence of supragingival plaque on facial and lingual surfaces was determined by visual inspection; each tooth was dried with air and mouth mirror rotation was used to provide light reflection to identify plaque on smooth surfaces and at the tooth line angles. Gingival bleeding within 30 s after probing to full pocket depth was assessed in six sites of each tooth. Adverse events were evaluated by questionnaire and visual examination. RESULTS: All 30 patients in the study completed the baseline and the 2 wk parts of the study and a subset of 12 participants completed the 3 mo part of the study. The sodium hypochlorite rinse group and the water rinse group, respectively, showed increases from baseline to 3 mo of 94% and 29% (3.2-fold difference) in plaque-free facial surfaces, of 195% and 30% (6.5-fold difference) in plaque-free lingual surfaces, and of 421% and 29% (14.5-fold difference) in number of teeth with no bleeding on probing. The differences in clinical improvement between the sodium hypochlorite rinse group and the water rinse group were statistically significant. No adverse events were identified in any of the study patients, except for minor complaints about the taste of bleach. CONCLUSION: A twice-weekly oral rinse with 0.25% sodium hypochlorite produced marked decreases in dental plaque level and bleeding on probing and may constitute a promising new approach to the management of periodontal disease. Long-term controlled studies on the effectiveness of sodium hypochlorite oral rinse are needed and encouraged.


Asunto(s)
Antiinfecciosos Locales/administración & dosificación , Antisépticos Bucales/administración & dosificación , Periodontitis/tratamiento farmacológico , Hipoclorito de Sodio/administración & dosificación , Adulto , Carga Bacteriana/efectos de los fármacos , Placa Dental/tratamiento farmacológico , Placa Dental/microbiología , Femenino , Estudios de Seguimiento , Fusobacterium/efectos de los fármacos , Hemorragia Gingival/tratamiento farmacológico , Gingivitis/tratamiento farmacológico , Bacterias Gramnegativas/efectos de los fármacos , Humanos , Masculino , Satisfacción del Paciente , Bolsa Periodontal/tratamiento farmacológico , Periodontitis/microbiología , Proyectos Piloto , Método Simple Ciego , Irrigación Terapéutica/métodos
17.
Plant Dis ; 98(12): 1748, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30703919

RESUMEN

In February 2014, a severe disease on maize (Zea mays L.) broke out in the fields of central and southwestern Taiwan and caused yield losses in sweet corn production. Chlorotic spots first appeared at the base of infected leaves and later developed into systemic mottling. Diffused necrotic patches were also found on leaves or husks of the diseased plants. Moreover, severe rosetting and stunting accompanied by abnormalities in ear production were observed on mature plants. Eighteen leaf samples from symptomatic plants were collected and submitted to our Plant Diagnostic Clinic for virus diagnosis. All of the samples were first tested by reverse transcriptase (RT)-PCR to detect Maize stripe virus (MSpV) and by indirect ELISA to detect Maize dwarf mosaic virus (MDMV) or Sugarcane mosaic virus (SCMV), which were endemic to this area (1). Only 2 out of 18 samples were positive for MDMV, SCMV, or mixed infection of both viruses. Sap inoculation tests conducted on seedlings of sweet corn cv. Honey 236 indicated that the MDMV- and SCMV-negative samples still had an unknown pathogen causing original symptoms in the receptor plants. The isolate from Yunlin county reacted only with the antibody to Maize chlorotic mottle virus (MCMV) (AC Diagnostics, Fayetteville, AR) in ELISA. For further identification, the MCMV-specific primers (forward: MCMVg3514F-GGGAACAACCTGCTCCA; reverse MCMVg4014R-GGACACGGAGTACGAGA) were designed from the nucleotide sequence of MCMV coat protein (CP) gene. In RT-PCR using the AccuPower RT/PCR PreMix kit (Bioneer, Daejeon, Korea), an expected 500-bp DNA fragment was observed. This PCR product was cloned and its nucleotide sequence was determined by Mission Biotech Co., Taipei, Taiwan. BLAST analysis of the CP gene of the MCMV-Yunlin revealed the maximum nucleotide identities (99%) with Chinese Sichuan isolates (GenBank Accession No. JQ984270) and 98% identities to four Chinese Yunnan isolates (GU138674, JQ982468, JQ982469, and KF010583) and one Kenya isolate (JX286709), compared with 97% to Kansas isolate (X14736) and 96% to Nebraska isolate (EU358605). Subsequently, the complete nucleotide sequence of the viral genome (KJ782300) was determined from five overlapping DNA fragments obtained from independent RT-PCR amplification. The virus isolate was infectious to sweet corn cultivars Bai-long-wang, Devotion, SC-34, SC2015, and Zheng-zi-mi, on which similar symptoms were developed after mechanical inoculation. During the spring of 2014, a total of 224 sweet corn samples were collected from the epidemic areas of Taichung, Yunlin, Chiayi, and Kaohsiung counties. Samples (n= 161) reacted positive for MCMV in ELISA and/or RT-PCR. In the field survey, more than 20 adult thrips might be observed on an MCMV-infected plant. Two species of Frankliniella were found on maize plants: F. williamsi Hood and F. intonsa Trybom. Maize thrips (F. williamsi), an occasional pest of maize occurring during winter and spring in Taiwan, was characterized by its abdominal sternite II on which 1 or 2 discal setae of equal length with posteromarginal setae were borne (2). Samples with 1, 5, 10, and 30 F. williamsi collected in the field were tested by RT-PCR; MCMV was detectable not only in the pooled crushed bodies but also in a single maize thrips. This is the first report of MCMV occurrence on maize in Taiwan and of the virus transmitted by maize thrips. References: (1) C. T. Chen et al. Taiwan Sugar 37(4):9, 1990. (2) C.-L. Wang et al. Zool. Stud. 49:824, 2010.

18.
Phys Rev Lett ; 111(2): 027203, 2013 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-23889435

RESUMEN

The magnetic properties of a Co2FeAl/(Ga,Mn)As bilayer epitaxied on GaAs (001) are studied both experimentally and theoretically. Unlike the common antiferromagnetic interfacial interaction existing in most ferromagnet-magnetic semiconductor bilayers, a ferromagnetic interfacial interaction in the Co2FeAl/(Ga,Mn)As bilayer is observed from measurements of magnetic hysteresis and x-ray magnetic circular dichroism. The Mn ions in a 1.36 nm thick (Ga,Mn)As layer remain spin polarized up to 400 K due to the magnetic proximity effect. The minor loops of the Co2FeAl/(Ga,Mn)As bilayer shift with a small ferromagnetic interaction field of +24 Oe and -23 Oe at 15 K. The observed ferromagnetic interfacial coupling is supported by ab initio density functional calculations. These findings may provide a viable pathway for designing room-temperature semiconductor spintronic devices through magnetic proximity effect.

19.
Plant Dis ; 97(9): 1132-1136, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30722420

RESUMEN

Guava wilt, caused by Nalanthamala psidii, has become an important disease of guava (Psidium guajava) in Taiwan since the 1970s. This study was conducted to develop a semiselective medium for detecting N. psidii in soil and in tissues of diseased guava trees. Among 9 carbon and 21 nitrogen compounds tested in a modified Czapek-Dox medium, the most effective carbon and nitrogen sources for mycelial growth of N. psidii were sucrose and glycine, respectively. Among eight fungicides tested, iprodione at 5 µg ml-1 and azoxystrobin at 1 µg ml-1 were the most effective fungicides for detection of N. psidii in artificially infested soil or in naturally infected guava debris. Based on the requirement for carbon and nitrogen sources and response to fungicides, a semiselective medium designated as modified sucrose-glycine semiselective medium (mSGSSM) was developed for isolation of N. psidii, using the modified Czapek-Dox medium containing 3% sucrose, 0.3% glycine, iprodione at 5 µg ml-1, azoxystrobin at 1 µg ml-1, streptomycin at 200 µg ml-1, and neomycin at 200 µg ml-1. Colonies of N. psidii on mSGSSM at 30°C for 5 to 10 days were white to orange with sparse aerial hyphae. N. psidii was detected more accurately and efficiently on mSGSSM than on other media, including potato dextrose agar, modified Nash-Snyder medium, and modified Czapek-Dox medium. This semiselective medium is effective in detection of N. psidii from various parts of diseased guava trees and in soil; therefore, it would be a useful medium for etiological, ecological, and epidemiological studies of guava wilt.

20.
Br J Cancer ; 106(3): 475-81, 2012 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-22187040

RESUMEN

BACKGROUND: Activating mutations of Fms-like tyrosine kinase 3 (FLT3) constitute a major driver in the pathogenesis of acute myeloid leukaemia (AML). Hence, pharmacological inhibitors of FLT3 are of therapeutic interest for AML. METHODS: The effects of inhibition of FLT3 activity by a novel potent FLT3 inhibitor, BPR1J-097, were investigated using in vitro and in vivo assays. RESULTS: The 50% inhibitory concentration (IC(50)) of BPR1J-097 required to inhibit FLT3 kinase activity ranged from 1 to 10 nM, and the 50% growth inhibition concentrations (GC(50)s) were 21±7 and 46±14 nM for MOLM-13 and MV4-11 cells, respectively. BPR1J-097 inhibited FLT3/signal transducer and activator of transcription 5 phosphorylation and triggered apoptosis in FLT3-driven AML cells. BPR1J-097 also showed favourable pharmacokinetic property and pronounced dose-dependent tumour growth inhibition and regression in FLT3-driven AML murine xenograft models. CONCLUSION: These results indicate that BPR1J-097 is a novel small molecule FLT-3 inhibitor with promising in vivo anti-tumour activities and suggest that BPR1J-097 may be further developed in preclinical and clinical studies as therapeutics in AML treatments.


Asunto(s)
Benzamidas/uso terapéutico , Leucemia Mieloide Aguda/tratamiento farmacológico , Inhibidores de Proteínas Quinasas/uso terapéutico , Sulfonamidas/uso terapéutico , Tirosina Quinasa 3 Similar a fms/antagonistas & inhibidores , Animales , Benzamidas/química , Benzamidas/farmacología , Proliferación Celular/efectos de los fármacos , Células HEK293/efectos de los fármacos , Humanos , Indazoles/farmacología , Concentración 50 Inhibidora , Leucemia Mieloide Aguda/enzimología , Leucemia Mieloide Aguda/patología , Masculino , Ratones , Ratones Desnudos , Compuestos de Fenilurea/farmacología , Inhibidores de Proteínas Quinasas/química , Inhibidores de Proteínas Quinasas/farmacología , Ratas , Ratas Sprague-Dawley , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Sulfonamidas/química , Sulfonamidas/farmacología , Células Tumorales Cultivadas/efectos de los fármacos
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