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1.
J Environ Manage ; 360: 121126, 2024 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-38761629

RESUMEN

Soil salinization is a significant global issue that leads to land degradation and loss of ecological function. In coastal areas, salinization hampers vegetation growth, and forestation efforts can accelerate the recovery of ecological functions and enhance resilience to extreme climates. However, the salinity tolerance of tree species varies due to complex biological factors, and results between lab/greenhouse and field studies are often inconsistent. Moreover, in salinized areas affected by extreme climatic and human impacts, afforestation with indigenous species may face adaptability challenges. Therefore, it is crucial to select appropriate cross-species salinity tolerance indicators that have been validated in the field to enhance the success of afforestation and reforestation efforts. This study focuses on five native coastal tree species in Taiwan, conducting afforestation experiments on salt-affected soils mixed with construction and demolition waste. It integrates short-term controlled experiments with potted seedlings and long-term field observations to establish growth performance and physiological and biochemical parameters indicative of salinity tolerance. Results showed that Heritiera littoralis Dryand. exhibited the highest salinity tolerance, accumulating significant leaf proline under increased salinity. Conversely, Melia azedarach Linn. had the lowest tolerance, evidenced by complete defoliation and reduced biomass under salt stress. Generally, the field growth performance of these species aligns with the results of short-term pot experiments. Leaf malondialdehyde content from pot experiments proved to be a reliable cross-species salinity tolerance indicator, correlating negatively with field relative height growth and survival rates. Additionally, parameters related to the photosynthetic system or water status, measured using portable devices, also moderately indicated field survival, aiding in identifying potential salt-tolerant tree species. This study underscores the pivotal role of species selection in afforestation success, demonstrating that small-scale, short-term salinity control experiments coupled with appropriate assessment tools can effectively identify species suitable for highly saline and degraded environments. This approach not only increases the success of afforestation but also conserves resources needed for field replanting and maintenance, supporting sustainable development goals.

2.
Cancer Gene Ther ; 2024 Feb 28.
Artículo en Inglés | MEDLINE | ID: mdl-38418842

RESUMEN

This study utilized Next-Generation Sequencing (NGS) to explore genetic determinants of survival duration in Glioblastoma Multiforme (GBM) patients. We categorized 30 primary GBM patients into two groups based on their survival periods: extended survival (over two years, N = 17) and abbreviated survival (under two years, N = 13). For identifying pathogenic or likely pathogenic variants, we leveraged the ClinVar database. The cohort, aged 23 to 66 (median: 53), included 17 patients in Group A (survival >2 years, 10 males, 7 females), and 13 patients in Group B (survival <2 years, 8 males, 5 females), with a 60% to 40% male-to-female ratio. Identified mutations included CHEK2 (c.1477 G > A, p.E493K), IDH1 (c.395 G > A, p.R132H), and TP53 mutations. Non-coding regions exhibited variants in the TERT promoter (c.-146C > T, c.-124C > T) and TP53 RNA splicing site (c.376-2 A > C, c.376-2 A > G). While Group A had more mutations, statistical significance wasn't reached, likely due to sample size. Notably, TP53, and ATR displayed a trend toward significance. Surprisingly, TP53 mutations were more prevalent in Group A, contradicting Western findings on poorer GBM prognosis. In Taiwanese GBM patients, bevacizumab usage is linked to improved survival rates, affirming its safety and effectiveness. EGFR mutations are infrequent, suggesting potential distinctions in carcinogenic pathways. Further research on EGFR mutations and amplifications is essential for refining therapeutic approaches. TP53 mutations are associated with enhanced survival, but their functional implications necessitate detailed exploration. This study pioneers genetic analysis in Taiwanese GBM patients using NGS, advancing our understanding of their genetic landscape.

3.
J Chin Med Assoc ; 84(11): 1019-1022, 2021 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-34261980

RESUMEN

BACKGROUND: Dopamine agonists such as bromocriptine and cabergoline have been found to be an effective treatment for hyperprolactinemia, not only inducing adenoma shrinkage but also lowering serum prolactin levels. Among known dopamine agonists, cabergoline is the drug of choice due to its enhanced tolerability compared with bromocriptine. This study aimed to evaluate cabergoline's effectiveness, along with transsphenoidal surgery, in the treatment of hyperprolactinemia. METHODS: We retrieved all patients with a diagnosis of prolactinoma who were treated in our hospital during 2000-2018. A total of 208 patients were enrolled in the analysis after applying exclusion criteria. Patients were divided into four groups according to the treatments received. The demographic data, dosage and duration of cabergoline, and serum prolactin levels at different time points were collected for analysis. RESULTS: Normalization was achieved in 59 patients (83.10%) within a short median duration of 2.80 months among those treated with cabergoline only. Although cabergoline alone was effective and well-tolerated, our data showed that long-term remission rates were more favorable when surgery was involved. The long-term remission rate of all patients enrolled was 53.8% (112 patients among 208 patients). The long-term remission rates for the different treatment groups were 17.8% (8 of 45 patients) in Group 1 (Operation→Drug), 83.3% (5 of 6 patients) in Group 2 (Drug→Operation), 79.0% (68 of 86 patients) in Group 3 (Operation only), and 43.7% (31 of 71 patients) in Group 4 (Drug only). CONCLUSION: Cabergoline has been demonstrated to be effective and should be considered as a first-line treatment for hyperprolactinemia. In our study, transsphenoidal surgery was also demonstrated to achieve good results compared with medical treatment. Surgical intervention may resurface as an alternative first-line treatment. When used in combination with cabergoline, surgery offers a higher disease remission rate than either drug or operation alone.


Asunto(s)
Cabergolina/uso terapéutico , Agonistas de Dopamina/uso terapéutico , Hiperprolactinemia/tratamiento farmacológico , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad
4.
BMC Infect Dis ; 20(1): 112, 2020 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-32041539

RESUMEN

BACKGROUND: Pneumocystis pneumonia (PCP) is increasingly being diagnosed in patients with systemic lupus erythematosus (SLE), and hydroxychloroquine (HCQ) has been found to possess antifungal activities. We hence aimed to investigate the association between HCQ and PCP risk among patients with SLE. METHODS: Using the 1997-2013 nationwide claim data, we identified 24,343 newly-diagnosed SLE patients. We then identified 58 PCP cases and selected 348 non-PCP controls matching (1:6) by age, sex, disease duration and the year of PCP diagnosis date. The risk of PCP was assessed by determing odds ratios (ORs) with 95% confidence intervals (CIs) by using multivariable conditional logistic regression. RESULTS: The risk of PCP was associated with moderate to severe renal disease (OR 6.73, 95% CI 1.98-22.92), higher doses of glucocorticoids (≤5 mg/day, reference; 5-10 mg/day, OR 25.88, 95% CI 2.97-225.33; > 10 mg/day, OR 286.58, 95% CI 28.58-> 999), higher 3-month cumulative dose of cyclophosphamide (not use, reference; ≤1.4 g, OR 0.64, 95% CI 0.14-3.01; > 1.4 g, OR 11.52, 95% CI 1.97-67.39) and use of mycophenolate mofetil/mycophenolic acid (OR 50.79, 95% CI 5.32-484.77), whereas 3-month cumulative dose of HCQ was associated with a reduced risk of PCP among patients with SLE (not use, reference; ≤14 g, OR 0.69, 95% CI 0.21-2.24; > 14 g, OR 0.20, 95% CI 0.05-0.71). CONCLUSIONS: This study demonstrated incident PCP was associated with mycophenolate mofetil/mycophenolic acid use and higher doses of cyclophosphamide or glucocorticoid, whereas the use of a higher dose of HCQ was associated with a reduced risk of PCP in lupus patients.


Asunto(s)
Antifúngicos/uso terapéutico , Antirreumáticos/uso terapéutico , Hidroxicloroquina/uso terapéutico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Neumonía por Pneumocystis/prevención & control , Adulto , Estudios de Casos y Controles , Femenino , Glucocorticoides/uso terapéutico , Humanos , Modelos Logísticos , Lupus Eritematoso Sistémico/epidemiología , Masculino , Persona de Mediana Edad , Ácido Micofenólico/uso terapéutico , Neumonía por Pneumocystis/epidemiología , Estudios Retrospectivos , Adulto Joven
5.
Beilstein J Nanotechnol ; 9: 1602-1612, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29977694

RESUMEN

We produced an anodic aluminum oxide (AAO) structure with periodic nanopores on the surface of flip-chip blue light-emitting diodes (FC-BLEDs). The nanopores had diameters ranging from 73 to 85 nm and were separated by distances ranging from approximately 10 to 15 nm. The light extraction efficiency enhancement of the FC-BLEDs subjected to different durations of the second pore-widening process was approximately 1.6-2.9%. The efficiency enhancement may be attributed to the following mechanism: periodic nanopores on the surface of FC-BLEDs reduce the critical angle of total reflection and effective energy transfer from a light emitter into a surface plasmon mode produced by AAO.

7.
Nanoscale Res Lett ; 9(1): 652, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25520599

RESUMEN

Numerical simulations are conducted to study the current-matching effect and operation mechanisms in and to design the optimized device structure of InGaN/Si tandem cells. The characteristics of short circuit current density (J sc), open circuit voltage (V oc), fill factor (FF), and conversion efficiency (η) of InGaN/Si tandem cells are determined by the current-matching effect. The similar trend of η to that of J sc shows that J sc is a dominant factor in determining the performance of InGaN/Si tandem cells. In addition, the combined effects of the J sc, V oc, and FF lead to an optimized η in the medium-indium, [Formula: see text], InGaN/Si tandem cell. At [Formula: see text], the J sc of the InGaN subcell is equal to that of the Si subcell such that an InGaN/Si tandem cell reaches the current matching condition to operate at the maximum power point. Similar to the J sc and FF, the η for low- [Formula: see text] and high-In [Formula: see text] InGaN/Si tandem cells are InGaN- and Si subcell-limited, respectively. Furthermore, the p- and n-layer thicknesses, indium content, and position of depletion region of InGaN subcell should be adjusted to reapportion the light between the two subcells and to achieve the maximum conversion efficiency. With appropriate thicknesses of p- and n-InGaN, In0.5-0.6Ga0.5-0.4 N/Si tandem cells can exhibit as high as approximately 34% to 36.5% conversion efficiency, demonstrating that a medium-indium InGaN/Si tandem cell results in a high-efficiency solar cell. Simulation results determine that the current-matching effect and operation mechanisms of InGaN/Si tandem cells can be utilized for efficiency enhancement through the optimized device structures.

8.
J Biomed Opt ; 19(2): 21110, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24084890

RESUMEN

A swept source (SS)-based circular-state (CS) polarization-sensitive optical coherence tomography (PS-OCT) constructed entirely with polarization-maintaining fiber optics components is proposed with the experimental verification. By means of the proposed calibration scheme, bulk quarter-wave plates can be replaced by fiber optics polarization controllers to, therefore, realize an all-fiber optics CS SSPS-OCT. We also present a numerical dispersion compensation method, which can not only enhance the axial resolution, but also improve the signal-to-noise ratio of the images. We demonstrate that this compact and portable CS SSPS-OCT system with an accuracy comparable to bulk optics systems requires less stringent lens alignment and can possibly serve as a technology to realize PS-OCT instrument for clinical applications (e.g., endoscopy). The largest deviations in the phase retardation (PR) and fast-axis (FA) angle due to sample probe in the linear scanning and a rotation angle smaller than 65 deg were of the same order as those in stationary probe setups. The influence of fiber bending on the measured PR and FA is also investigated. The largest deviations of the PR were 3.5 deg and the measured FA change by ~12 to 21 deg. Finally, in vivo imaging of the human fingertip and nail was successfully demonstrated with a linear scanning probe.


Asunto(s)
Tecnología de Fibra Óptica , Tomografía de Coherencia Óptica/métodos , Calibración , Endoscopía/métodos , Diseño de Equipo , Dedos/patología , Análisis de Fourier , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Uñas/patología , Óptica y Fotónica , Reproducibilidad de los Resultados , Procesamiento de Señales Asistido por Computador , Relación Señal-Ruido
9.
Opt Express ; 21(16): 19280-91, 2013 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-23938845

RESUMEN

The use and advantages of applying balanced-detection (BD) operation method to high speed spectral domain optical coherence tomography (SDOCT) are presented in this study, which we believe is the first such demonstration. Compared to conventional SDOCT, BD-SDOCT provides two unique advantages. First, the method can suppress background noise and autocorrelation artifacts in biological tissues. Second, it is a power-efficient method which is particularly helpful for high speed SDOCT to eliminate random intensity noise and to achieve shot noise limited detection. This performance allows in vivo three-dimensional tissue visualization with high imaging quality and high speed.

10.
Appl Opt ; 51(24): 5936-40, 2012 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-22907025

RESUMEN

In this study, the use and advantages of balanced detection (BD) in spectral domain optical coherence tomography (SD-OCT) are demonstrated. A-scans are calculated as a combination of two phase-opposed interferometric spectra acquired simultaneously by using a multiline single camera spectrometer. Not only does this system suppress artifacts due to autocorrelation, but also the signal of interest is increased by a factor of 2 as experimentally verified. Our BD-based SD-OCT gives a signal-to-noise ratio improvement of 8-14 dB for the peak within 1 mm compared to standard SD-OCT using a single detection scheme. This method is validated by experimental measurement of a glass plate.


Asunto(s)
Tomografía de Coherencia Óptica/instrumentación , Tomografía de Coherencia Óptica/métodos , Algoritmos , Diseño de Equipo , Análisis de Fourier , Interferometría/métodos , Espectrofotometría/métodos
11.
Appl Opt ; 46(13): 2520-7, 2007 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-17429466

RESUMEN

Polarization-sensitive optical coherence tomography (PS-OCT) combines the advantages of OCT with image contrast enhancement, which is based on its ability to detect phase retardation and the fast-axis angle. Both PS-OCT images and histopathology have demonstrated similar features that allowed differentiation of atherosclerotic structures (i.e., plaques) from normal tissue. Moreover, the picrosirius polarization method was used to confirm PS-OCT assessment of collagen in the fibrous cap of atherosclerotic plaques, and high-frequency (40 MHz) ultrasound images were used to identify calcium in the vessel wall. Our preliminary ex vivo investigation of human aortic specimens indicated that PS-OCT might help to identify atherosclerotic lesions.


Asunto(s)
Aorta/patología , Enfermedad de la Arteria Coronaria/patología , Aumento de la Imagen/instrumentación , Refractometría/instrumentación , Tomografía de Coherencia Óptica/instrumentación , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Aumento de la Imagen/métodos , Técnicas In Vitro , Refractometría/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tomografía de Coherencia Óptica/métodos
12.
Nat Nanotechnol ; 2(11): 704-8, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-18654409

RESUMEN

Coherent acoustic phonons are generated at terahertz frequencies when semiconductor quantum-well nanostructures are illuminated by femtosecond laser pulses. These phonons-also known as nanoacoustic waves-typically have wavelengths of tens of nanometres, which could prove useful in applications such as non-invasive ultrasonic imaging and sound amplification by the stimulated emission of radiation. However, optical diffraction effects mean that the nanoacoustic waves are produced with spot sizes on the micrometre scale. Near-field optical techniques can produce waves with smaller spot sizes, but they only work near surfaces. Here, we show that a far-field optical technique--which suffers no such restrictions--can be used to spatially manipulate the phonon generation process so that nanoacoustic waves are emitted with lateral dimensions that are much smaller than the laser wavelength. We demonstrate that nanoacoustic waves with wavelengths and spot sizes of the order of 10 nm and 100 nm, respectively, can be generated and detected.


Asunto(s)
Acústica , Modelos Teóricos , Nanosferas/química , Óptica y Fotónica , Simulación por Computador , Dispersión de Radiación
13.
Conf Proc IEEE Eng Med Biol Soc ; 2005: 3192-5, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-17282923

RESUMEN

A novel polarization-sensitive optical coherence tomography (PS-OCT) using only linearly polarized light is proposed. To compare with conventional PS-OCT which use circular polarized incident light, linear PS-OCT shows three advantages: (1) in a turbid medium with linear birefringence, the degree of polarization of backscattered light for linearly incident light dose not change significantly; (2) Phase retardation (PR) of the sample can be obtained totally from the phase-difference between the polarization heterodyne signals, thus common phase noise rejection mode is introduced inherently. These advantages lead to the immunity of background phase noise and laser frequency noise simultaneously, and also lead to the better sensitivity of PR measurements; (3) the dynamic range of PR in this system is between 0° to 180°, which is two times larger than that of conventional circular PS-OCT.

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