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1.
J Invest Dermatol ; 144(2): 243-251.e2, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37598868

RESUMO

Efficient clearance of dead cells is critical for tissue regeneration after injuries. How dead cells are removed from the skin after radiotherapy and chemotherapy is unclear. In this study, we found that radiotherapeutic and chemotherapeutic damage induced extensive apoptosis of highly proliferative transit-amplifying cells in hair follicles. These apoptotic cells disappeared rapidly in the early stage of regenerative attempts, and the lost structures were regenerated with transient and low-level inflammation. Without the recruitment of macrophages as scavengers, the dying cells were engulfed directly by adjacent surviving transit-amplifying cells, which produced mature phagosomes through fusion with lysosomes in a manner similar to professional phagocytosis and remained active in proliferation. Autophagy did not contribute significantly to the clearance of engulfed cell debris. Perturbing phagocytosis in the transit-amplifying cells hindered apoptotic cell removal, delayed structural recovery, and aggravated hair loss. Therefore, transit-amplifying cells are capacitated with both proliferative and efferocytic functions that facilitate tissue regeneration after tissue injury.


Assuntos
Folículo Piloso , Fagocitose , Humanos , Alopecia , Pele , Macrófagos
2.
Sci Total Environ ; 874: 162519, 2023 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-36870502

RESUMO

Coastal tidal wetlands are sufficiently acknowledged for the supplied vital ecosystem functions, including flood protection and biological conservation. Measuring and estimating reliable topographic data is essential for quantifying mangrove habitat quality. This study proposes a novel methodology for quickly constructing a digital elevation model (DEM) with an instantaneous waterline combined with tidal level records. Unmanned aerial vehicles (UAVs) enabled on-site waterline interpretation analysis. The results show that image enhancement improves the accuracy of waterline recognition and object-based image analysis has the highest accuracy. The waterline DEM (WDEM) performs a more accurate elevation production than UAV DEM, indicating that its application to habitat evaluation and prediction could be more reliable. Hydrodynamic simulations incorporated with the mangrove habitat model were utilized to calculate inundation duration, flow resistance, and vegetation dissipation potential according to the verified WDEM. The larger the mangrove coverage ratio, the stronger the flow resistance, which means that the protective consequence of the mangrove on the natural embankment is evident. The WDEM and nature-based solutions presented facilitate an adequate understanding of coastal protection and promote the potential ecosystem-based disaster risk reduction of mangrove wetlands.

3.
Sci Total Environ ; 851(Pt 1): 158097, 2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-35988606

RESUMO

The mangrove ecosystem is significantly affected by human activities, climate change, and rising sea level. The propagules of mangroves dispersal with tide and river currents that extend upstream habitats are why mangroves are the dominant species in the tidal area. Bridging critical knowledge gaps can help to create restoration plans for mangrove extension. However, studies on the hydrodynamic and propagation trajectory model (PTM) simulation of propagule long-distance dispersal (LDD) and mangrove growth potential are scarce. By combining various numerical methods and empirical formulas and verifying them with the data obtained through field surveys, this study established a comprehensive model to assess the dispersal and growth of the propagules of Kandelia ovobata. The stepping-stone approach (SSA) and habitat suitability index (HSI) model were also employed to determine the location of the appropriate new habitats through iterative simulation in propagule dispersal. Dike removal was proposed as a nature-based solution and modeled to evaluate the benefits of ecological conservation and flood prevention. The PTM simulations indicated that the deterministic process of horizontal advection accounted for >80 %, and that the remaining variability in the model could be explained by stochastic processes in predicting mangrove propagules pathways. The integrated model of the PTM and SSA proved that propagules have LDD in an estuary. There were few matches in the regions for mangrove growth when comparing the suitability of habitat distribution and the probability of propagule movement. We suggested that the mangrove spread model incorporating the SSA and HSI models predict the potential for mangrove dispersal into new habitats. In addition, the removal of levees aids floodplain regeneration and allows propagules to disperse across the floodplain at high tide and establishment at low tide. The Guandu floodplain restoration with dike removal supplied a cobenefits on ecological demands and flood risk reduction. Future research could thus utilize the adaptation and mitigation strategies presented in this study by incorporating socioeconomic considerations to enhance practical feasibility.


Assuntos
Ecossistema , Rhizophoraceae , Mudança Climática , Estuários , Áreas Alagadas
4.
Environ Int ; 139: 105669, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32278196

RESUMO

To better understand air pollution problems, the relationships between PM2.5 and hydro-meteorological variables are studied using a state-of-the-art multivariate nonlinear and non-stationary filtering method, noise-assisted multivariate empirical mode decomposition (NAMEMD), and the time-dependent intrinsic correlation (TDIC) algorithm. Three characteristic scales (annual, diurnal and semi-diurnal) are shown to be significant to PM2.5 characterization, based on using NAMEMD filtering. Temporal fluctuations of local correlations among PM2.5 and hydro-meteorological variables are presented. On diurnal and semi-diurnal scales, seasonal variation of the local correlation between temperature and humidity is observed. A combined wind speed and direction analysis can be conducted using the NAMEMD-based algorithm. The pollutant roses that are generated from the reconstructed wind directions reveal the sources of PM2.5 on different scales. PM2.5 is found to be related to land breeze at the diurnal scale and to winter monsoons at the annual scale. The scale-dependent wind direction that contributes to the increase of PM2.5 can be identified.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Monitoramento Ambiental , Conceitos Meteorológicos , Material Particulado/análise , Estações do Ano , Taiwan , Vento
5.
Oncotarget ; 8(39): 65281-65291, 2017 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-29029430

RESUMO

Epigenetic dysregulation is important in cervical cancer development, but the underlying mechanism is largely unknown. Increasing evidence indicates that DNA methylation is sensitive to changes in microenvironmental factors, such as nitric oxide (NO) in the chronic inflammatory cervix. However, the epigenomic effects of NO in cancer have not been investigated. In this study, we explored the methylomic effects of nitroxidative stress in HPV-immortalized precancerous cells. Chronic NO exposure promoted the acquisition of malignant phenotypes such as cell growth, migration, invasion, and anchorage-independent growth. Epigenetic analysis confirmed hypermethylation of PTPRR. Whole-genome methylation analysis showed BOLA2B, FGF8, HSPA6, LYPD2, and SHE were hypermethylated in cells. The hypermethylation BOLA2B, FGF8, HSPA6, and SHE was confirmed in cervical scrapings from invasive cancer, but not in CIN3/CIS, CIN2 and CIN1 (p=0.019, 0.023, 0.023 and 0.027 respectively), suggesting the role in the transition from in situ to invasive process. Our results reveal that nitroxidative stress causes epigenetic changes in HPV-infected cells. Investigation of these methylation changes in persistent HPV infection may help identify new biomarkers of DNA methylation for cervical cancer screening, especially for precancerous lesions.

6.
Materials (Basel) ; 10(7)2017 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-28773187

RESUMO

A novel nanoarchitecture-reinforced poly(lactic acid) (PLA) nanocomposite was prepared using multi-walled carbon nanotube (MWCNT)-grafted silica nanohybrids as reinforcements. MWCNT-grafted silica nanohybrids were synthesized by the generation of silica nanoparticles on the MWCNT surface through the sol-gel technique. This synthetic method involves organo-modified MWCNTs that are dispersed in tetrahydrofuran, which incorporates tetraethoxysilane that undergoes an ultrasonic sol-gel process. Gelation yielded highly dispersed silica on the organo-modified MWCNTs. The structure and properties of the nanohybrids were established using 29Si nuclear magnetic resonance, Raman spectroscopy, wide-angle X-ray diffraction, thermogravimetric analysis, and transmission electron microscopy. The resulting MWCNT nanoarchitectures were covalently assembled into silica nanoparticles, which exhibited specific and controllable morphologies and were used to reinforce biodegradable PLA. The tensile strength and the heat deflection temperature (HDT) of the PLA/MWCNT-grafted silica nanocomposites increased when the MWCNT-grafted silica was applied to the PLA matrix; by contrast, the surface resistivity of the PLA/MWCNT-grafted silica nanocomposites appeared to decline as the amount of MWCNT-grafted silica in the PLA matrix increased. Overall, the reinforcement of PLA using MWCNT-grafted silica nanoarchitectures was efficient and improved its mechanical properties, heat resistance, and electrical resistivity.

7.
Sci Adv ; 2(10): e1600964, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27819046

RESUMO

Formation of multifunctional, heterogeneous, and encoded hydrogel building blocks, or microgels, by crosslinking and assembly of microgels are two essential steps in establishing hierarchical, complicated, and three-dimensional (3D) hydrogel architectures that recapitulate natural and biological structures or originate new materials by design. However, for the variety of the hydrogel materials crosslinked differently and for the varied scales of microgels and architectures, the formation and assembly processes are usually performed separately, which increases the manufacturing complexity of designed hydrogel materials. We show the construction of hydrogel architectures through programmable formation and assembly on an electromicrofluidic platform, adopting two reciprocal electric manipulations (electrowetting and dielectrophoresis) to manipulate varied objects (i) in multiple phases, including prepolymer liquid droplets and crosslinked microgels, (ii) on a wide range of scales from micrometer functional particles or cells to millimeter-assembled hydrogel architectures, and (iii) with diverse properties, such as conductive and dielectric droplets that are photocrosslinkable, chemically crosslinkable, or thermally crosslinkable. Prepolymer droplets, particles, and dissolved molecules are electrically addressable to adjust the properties of the microgel building blocks in liquid phase that subsequently undergo crosslinking and assembly in a flexible sequence to accomplish heterogeneous and seamless hydrogel architectures. We expect the electromicrofluidic platform to become a general technique to obtain 3D complex architectures.

8.
Laryngoscope ; 124(1): 57-61, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24375023

RESUMO

OBJECTIVES/HYPOTHESIS: Sphenoid sinusitis is a complication associated with endoscopic transsphenoidal pituitary surgery. Studies that address the relationship between methods of sellar defect reconstruction and postoperative sinusitis are rare. The purpose of this study was to investigate the incidence, the possible risk factors, and the causative pathogens of sphenoid sinusitis after endoscopic transsphenoidal pituitary surgery. STUDY DESIGN: Prospective cohort study. METHODS: We performed a prospective analysis of 182 patients with benign pituitary tumor who underwent endoscopic transsphenoidal pituitary surgery and sellar defect reconstruction with bone chip, from July 2008 through July 2011. All patients were followed up with nasal endoscopy for at least 6 weeks. RESULTS: Fifty-seven (31.3%) patients developed postoperative sphenoid sinusitis. Comparing the sinusitis and nonsinusitis groups, we found that bone chip detachment was a significant risk factor for postoperative sinusitis, with a relative risk of 2.86 (64.1% vs. 22.4%). The most common pathogens present in cases of postoperative sinusitis were methicillin-sensitive Staphylococcus aureus, Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus. CONCLUSIONS: Regular follow-up with nasal endoscopy can prevent delayed diagnosis of postoperative sphenoid sinusitis. Culture-directed antibiotics with aggressive endoscopic debridement are an effective treatment for these patients. An optimal reconstruction strategy should be further developed to reduce bone chip detachment and secondary sinusitis.


Assuntos
Endoscopia/efeitos adversos , Neoplasias Hipofisárias/cirurgia , Sela Túrcica/cirurgia , Sinusite Esfenoidal/epidemiologia , Sinusite Esfenoidal/etiologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Sela Túrcica/patologia , Seio Esfenoidal , Sinusite Esfenoidal/microbiologia , Adulto Jovem
9.
Lab Chip ; 11(15): 2500-8, 2011 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-21666906

RESUMO

A water-core and oil-shell encapsulated droplet exhibits several advantages including enhanced fluidic manipulation, reduced biofouling, decreased evaporation, and simplified device packaging. However, obtaining the encapsulated droplet with an adjustable water-to-oil volume ratio and a further removable oil shell is not possible by reported techniques using manual pipetting or droplet splitting. We report a parallel-plate device capable of generation, encapsulation, rinsing, and emersion of water and/or oil droplets to achieve three major aims. The first aim of our experiments was to form encapsulated droplets by merging electrowetting-driven water droplets and dielectrophoresis-actuated oil droplets whose volumes were precisely controlled. 25 nL water droplets and 2.5 nL non-volatile silicone oil droplets with various viscosities (10, 100, and 1000 cSt) were individually created from their reservoirs to form encapsulated droplets holding different water-to-oil volume ratios of 10:1 and 2:1. Secondly, the driving voltages, evaporation rates, and biofouling of the precise encapsulated droplets were measured. Compared with the bare and immersed droplets, we found the encapsulated droplets (oil shells with lower viscosities and larger volumes) were driven at a smaller voltage or for a wider velocity range. In the dynamic evaporation tests, at a temperature of 20 ± 1 °C and relative humidity of 45 ± 3%, 10 cSt 10:1 and 2:1 encapsulated droplets were moved at the velocity of 0.25 mm s(-1) for 22 and 35 min until losing 16.6 and 17.5% water, respectively, while bare droplets followed the driving signal for only 6 min when 11.4% water was lost. Evaporation was further diminished at the rate of 0.04% min(-1) for a carefully positioned stationary encapsulated droplet. Biofouling of 5 µg ml(-1) FITC-BSA solution was found to be eliminated by the encapsulated droplet from the fluorescent images. The third aim of our research was to remove the oil shell by dissolving it in an on-chip rinsing reservoir containing hexane. After emersion from the rinsing reservoir, the bare droplet was restored as hexane rapidly evaporated. Removal of the oil shell would not only increase the evaporation of the core droplet when necessary, but also enhance the signal-to-noise ratio in the following detection steps.


Assuntos
Fluoresceína-5-Isotiocianato/química , Análise em Microsséries/instrumentação , Análise em Microsséries/métodos , Soroalbumina Bovina/química , Óleos de Silicone/química , Água/química , Animais , Bovinos , Fluorescência , Viscosidade
10.
J Occup Environ Hyg ; 7(11): 633-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20865628

RESUMO

Hand surface area is an important reference in occupational hygiene and many other applications. This study derives a formula for the palm surface area (PSA) and hand surface area (HSA) based on three-dimensional (3D) scan data. Two-hundred and seventy subjects, 135 males and 135 females, were recruited for this study. The hand was measured using a high-resolution 3D hand scanner. Precision and accuracy of the scanner is within 0.67%. Both the PSA and HSA were computed using the triangular mesh summation method. A comparison between this study and previous textbook values (such as in the U.K. teaching text and Lund and Browder chart discussed in the article) was performed first to show that previous textbooks overestimated the PSA by 12.0% and HSA by 8.7% (for the male, PSA 8.5% and HSA 4.7%, and for the female, PSA 16.2% and HSA 13.4%). Six 1D measurements were then extracted semiautomatically for use as candidate estimators for the PSA and HSA estimation formula. Stepwise regressions on these six 1D measurements and variable dependency test were performed. Results show that a pair of measurements (hand length and hand breadth) were able to account for 96% of the HSA variance and up to 98% of the PSA variance. A test of the gender-specific formula indicated that gender is not a significant factor in either the PSA or HSA estimation.


Assuntos
Antropometria/instrumentação , Antropometria/métodos , Mãos , Imageamento Tridimensional/instrumentação , Imageamento Tridimensional/métodos , Adolescente , Adulto , Superfície Corporal , Feminino , Humanos , Masculino , Computação Matemática , Pessoa de Meia-Idade , Análise de Regressão , Adulto Jovem
11.
Burns ; 34(8): 1183-9, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18539398

RESUMO

This study investigates the hand surface area (HSA) and palm surface area (PSA) percentages of body surface area (BSA). The HSA and PSA of 135 men and 135 women were measured by scanner and incorporated into an existing BSA database to derive %HSA/BSA and %PSA/BSA using five stature heights and three body weights in accordance with population distribution. Allowing for various degrees of specificity, the mean %HSA/BSA and mean %PSA/BSA were found to be 2.29% (0.24%) and 0.89% (0.09%), respectively. Gender and body weight group were significant factors.


Assuntos
Antropometria/métodos , Superfície Corporal , Mãos/anatomia & histologia , Adolescente , Adulto , Estatura , Índice de Massa Corporal , Peso Corporal , Bases de Dados Factuais , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Valores de Referência , Sensibilidade e Especificidade , Taiwan , Adulto Jovem
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