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1.
Sci Total Environ ; : 151619, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34780816

RESUMO

Mangroves have the potential to affect climate via C sequestration and methane (CH4) emissions. With half of the world's mangroves lost during the 20th century, mangrove restoration in mitigating greenhouse gases has been increasingly recognized. However, the carbon exchanges during restored processes still remain large uncertain. In this study, we analyzed the temporal variations of CO2 and CH4 fluxes and their environmental controls during 2019 and 2020 based on a closed-path eddy covariance (EC) system in a 12-year restored subtropical mangrove wetland, in estuary of the Pearl River, southeastern China. We also estimated the CO2 and CH4 fluxes and their climate effect from the beginning of restoration by Random Forest algorithm (RF). The EC observations showed that annually the 12-year restored mangrove acted as CO2 and CH4 sources, with net CO2 ecosystem exchange (NEE) of 82-175 gC·m- 2·a-1 and CH4 fluxes of 24.7-26.3 gC·m-2·a-1. Low vegetation gross primary productivity (GPP) and high ecosystem respiration (Re) caused net CO2 emissions in the mangroves. The estimation by RF indicated that the mangroves were always a CO2 source after the beginning of restoration, but the annual NEE was linearly decreased from 233 to 131 gC·m-2·a-1 from 2008 to 2020. The annual CH4 emissions continually increased from 19.0 to 25.8 gC·m-2·a-1 after restoration. As a result, the restored mangrove had a positive effect on climate warming, with increased GWP from 1276 to 1386 g CO2-eq ·m-2·a-1 from 2008 to 2020. This is mainly due to lower GPP and higher Re by young restored mangroves, large water area as well as low salinity induced strong CH4 emissions. Our results indicate new sights that young restored mangrove with large area of water surface may act as carbon sources. However, the long-term climate and ecosystem benefits due to mangrove restoration should not be ignored in future.

2.
J Transl Int Med ; 9(1): 38-42, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33850800

RESUMO

Objective: This study aims to explore the necessity and safety of digestive endoscopy during the epidemic of coronavirus disease 2019. Methods: A retrospective cohort study method was used to collect patients' data from the endoscopy center of the Civil Aviation General Hospital of China from February 1 to May 31, 2020, as the observation group. The patients' data of endoscopic diagnosis and treatment during the same period in 2019 were used as a control group, to compare the differences in the number of diagnosis and treatment and the detection rate of gastrointestinal diseases in the two groups. At the same time, patients and related staff were followed up for the situation of new infection. Results: During the epidemic, our endoscopy center conducted a total of 1,808 cases of endoscopic operations and 5,903 cases in the control group. The amount of endoscopic work during the epidemic period was 30.63% in the same period last year. During the epidemic, 26 patients underwent endoscopic mucosal resection (EMR)/endoscopic submucosal dissection (ESD) treatment, 26 patients underwent ERCP, and 18 patients underwent gastrointestinal stent implantation. In the control group, 273 patients underwent EMR/ESD, 17 underwent ERCP, and 16 underwent gastrointestinal stenting. During COVID-19, compared with the same period last year, the detection rates of peptic ulcer, esophageal cancer, gastric cancer, colon cancer, and rectal cancer were significantly higher (χ 2 = 4.482, P = 0.034; χ 2 = 5.223, P = 0.006; χ 2 = 2.329, P = 0.041; χ 2 = 8.755, P = 0.003; and χ 2 = 5.136, P = 0.023). Through telephone follow-up, novel coronavirus nucleic acid detection and blood antibody detection, no patients or medical staff were infected with the novel coronavirus. Conclusion: During COVID-19, the number of digestive endoscopic operations decreased significantly compared with the same period last year, but the detection rate of various diseases of the digestive tract increased significantly. On the basis of strict prevention and control, orderly recovery of endoscopic work is essential.

3.
Exp Mol Pathol ; 118: 104589, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33290799

RESUMO

OBJECTIVE: Androgenetic alopecia (AGA), a common alopecia, is often accompanied by abnormal expression of multiple miRNAs. This study aims to investigate abnormally expressed miRNAs in patients with AGA and their specific molecular mechanism. METHODS: miRNA microarray profiling and qRT-PCR validation were used to screen and verify abnormally expressed miRNAs in patients with AGA. Human hair follicles (HFs) were treated with different concentrations of dihydrotestosterone (DHT, 10-5, 10-6, 10-7 and 10-8 mol/L) for 10 days. The effects of DHT on HF growth, proliferation, and miRNA expression in cultured HFs were investigated using immunofluorescence staining and qRT-PCR. Moreover, human dermal papilla cells (HDPCs) were treated/transfected with a Wnt/ß-catenin pathway activator and/or miR-133b mimic, and then the CCK-8 assay was used to evaluate HDPC proliferation. qRT-PCR and Western blotting were used to measure the expression of Versican, ALP and ß-catenin RESULTS: miRNA microarray profiling identified 43 miRNAs that were significantly differentially expressed in AGA patients, and qRT-PCR verified that 8 miRNAs were significantly differentially expressed. The expression of miR-133b was abnormally high in AGA patients. DHT (10-5 mol/L) inhibited human HF growth and upregulated miR-133b expression, and DHT (10-7 mol/L) induced human HF growth and downregulated miR-133b expression. HDPC proliferation was inhibited, and the expression of ß-catenin was downregulated in the miR-133b mimic-transfected group compared with the control group (P < 0.05). Wnt/ß-catenin pathway activator treatment significantly promoted HDPC proliferation and upregulated the expression of ß-catenin (P < 0.05). In addition, the proliferation of HDPCs was not significantly different between the group cotreated with a Wnt/ß-catenin pathway activator and miR-133b mimic, and the control group (P > 0.05), but the expression of Versican and ALP was suppressed in the cotreatment group (P < 0.05) CONCLUSION: Our data indicated that patients with androgenic alopecia have specific miRNA expression profiles and that the abnormal expression of miR-133b may inactivate the Wnt/ß-catenin pathway and ultimately regulate hair growth.


Assuntos
Alopecia/patologia , Biomarcadores/metabolismo , Proliferação de Células , Regulação da Expressão Gênica , Folículo Piloso/crescimento & desenvolvimento , MicroRNAs/genética , Adulto , Alopecia/genética , Alopecia/metabolismo , Apoptose , Estudos de Casos e Controles , Células Cultivadas , Perfilação da Expressão Gênica , Folículo Piloso/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Via de Sinalização Wnt
4.
Front Pharmacol ; 10: 1528, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32038233

RESUMO

Dihydrotestosterone (DHT) is the most potent androgen that regulates hair cycling. Hair cycling involves cross-talk between the androgen and Wnt/ß-catenin pathways. However, how DHT regulates hair follicle (HF) growth through the Wnt/ß-catenin pathway has not been well investigated. This study aimed to investigate the roles of DHT in hair growth in vivo and in vitro. Human scalp HFs were treated with different concentrations of DHT (10-5, 10-6, 10-7, 10-8, and 10-9 mol/L) for 10 days. The effects of DHT on hair shaft elongation, the proliferation of hair matrix cells, and the levels of ß-catenin, GSK-3ß, and phosphorylated GSK-3ß (ser9) were evaluated in the cultured HFs. The effects of DHT were further investigated in C57BL/6 mice. Moreover, the growth of cultured human HFs was observed after interfering with the ß-catenin pathway through inhibitors or activators in the presence or absence of DHT. We found that different concentrations of DHT had different effects on human HFs in vitro and C57BL/6 mice. At 10-6 mol/L, DHT inhibited HF growth and ß-catenin/p-GSK-3ß expression, whereas 10-7 mol/L DHT induced HF growth and ß-catenin/p-GSK-3ß expression. In addition, a ß-catenin inhibitor (21H7) inhibited HF growth in vitro, while a ß-catenin activator (IM12) promoted HF growth in vitro and antagonized the inhibition of HFs by high levels of DHT. These results suggest that DHT plays a pivotal role in region-specific hair growth, which may be related to the Wnt/ß-catenin pathway.

5.
J Natl Med Assoc ; 111(3): 246-255, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30389146

RESUMO

BACKGROUND: The Medicare Modernization Act (MMA) drastically reduced reimbursement for androgen deprivation therapy (ADT) in 2005. One unintended consequence of the MMA may be an increase in the racial disparities in receipt of ADT. Given these policy changes, it becomes increasingly important to assess racial disparities in timely receipt of ADT. METHODS: The purpose of this study is to evaluate the associations between race and median time to receipt of ADT among men with metastatic prostate cancer before and after the passage of the MMA. A population-based retrospective cohort was created from the Surveillance, Epidemiology, and End Results-Medicare. RESULTS: A total of 1,846 African-American and 9,462 Caucasian men diagnosed with metastatic prostate cancer from 2000 through 2011 were included. An accelerated failure time regression model was used to examine factors associated with racial differences in median time to receipt of ADT. Results indicate that African-American men had a longer median time to receipt of ADT both before the MMA (Time Ratio (TR): 1.15; 95% Confidence Interval (CI) [1.05, 1.27]) and after the MMA (TR: 1.29; 95% CI [1.10, 1.53]) as compared to Caucasian men. In addition to race, men residing in South had longer median time to receipt of ADT (TR: 1.26, 1.52; 95% CI [1.01, 1.52; 1.24, 1.87] before and after MMA, respectively) compared to the Northeast region. CONCLUSION: Considering the palliative benefits of ADT, it is important to develop effective strategies to address racial differences in receipt of treatment for metastatic prostate cancer.


Assuntos
Afro-Americanos/estatística & dados numéricos , Antagonistas de Androgênios/uso terapêutico , Disparidades em Assistência à Saúde/etnologia , Neoplasias da Próstata/tratamento farmacológico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Grupo com Ancestrais do Continente Europeu/estatística & dados numéricos , Disparidades em Assistência à Saúde/estatística & dados numéricos , Humanos , Masculino , New England , Neoplasias da Próstata/etnologia , Estudos Retrospectivos , Programa de SEER , Sudeste dos Estados Unidos , Fatores de Tempo
6.
Lasers Med Sci ; 33(3): 637-645, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29468283

RESUMO

Activation of the Wnt/ß-catenin signaling pathway plays an important role in hair follicle morphogenesis and hair growth. Recently, low-level laser therapy (LLLT) was evaluated for stimulating hair growth in numerous clinical studies, in which 655-nm red light was found to be most effective and practical for stimulating hair growth. We evaluated whether 655-nm red light + light-emitting diode (LED) could promote human hair growth by activating Wnt/ß-catenin signaling. An in vitro culture of human hair follicles (HFs) was irradiated with different intensities of 655-nm red light + LED, 21 h7 (an inhibitor of ß-catenin), or both. Immunofluorescence staining was performed to assess the expression of ß-catenin, GSK3ß, p-GSK3ß, and Lef1 in the Wnt/ß-catenin signaling. The 655-nm red light + LED not only enhanced hair shaft elongation, but also reduced catagen transition in human hair follicle organ culture, with the greatest effectiveness observed at 5 min (0.839 J/cm2). Additionally, 655-nm red light + LED enhanced the expression of ß-catenin, p-GSK3ß, and Lef1, signaling molecules of the Wnt/ß-catenin pathway, in the hair matrix. Activation of Wnt/ß-catenin signaling is involved in hair growth-promoting effect of 655-nm red light and LED in vitro and therefore may serve as an alternative therapeutic option for alopecia.


Assuntos
Cabelo/crescimento & desenvolvimento , Luz , Técnicas de Cultura de Órgãos/métodos , Via de Sinalização Wnt/efeitos da radiação , Adulto , Animais , Cabelo/metabolismo , Cabelo/efeitos da radiação , Folículo Piloso/crescimento & desenvolvimento , Folículo Piloso/metabolismo , Folículo Piloso/efeitos da radiação , Humanos , Modelos Biológicos
7.
Fitoterapia ; 121: 136-140, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28723343

RESUMO

Oleanolic acid (OA), a pentacyclic triterpenoid compound which can be found in >1600 plants, has been shown to promote hair growth. To study the mechanisms of OA on hair growth, we investigated hair follicle (HF) growth on four different concentration OA using human hair follicle organ culture model. We found that HFs treated with 1 or 10µg/mL OA showed statistically enhanced elongation of the hair shaft and anagen-like stage. Moreover, higher positive rate of Ki-67, a matrix cellular marker of proliferation, was detected in the same groups treated with 1 or 10µg/mL than those treated with vehicle. We further demonstrated that ß-catenin, a key Wnt signaling transducer, was highly expressed in the OA treated groups using immunofluorescence stain assay. These results suggest that OA may promote human hair growth by stimulating hair matrix cell proliferation through the Wnt/ß-catenin pathway.


Assuntos
Proliferação de Células/efeitos dos fármacos , Folículo Piloso/efeitos dos fármacos , Ácido Oleanólico/farmacologia , beta Catenina/metabolismo , Adolescente , Adulto , Feminino , Cabelo/crescimento & desenvolvimento , Folículo Piloso/citologia , Folículo Piloso/crescimento & desenvolvimento , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Cultura de Órgãos , Via de Sinalização Wnt , Adulto Jovem
8.
J Gerontol A Biol Sci Med Sci ; 71(12): 1560-1563, 2016 12.
Artigo em Inglês | MEDLINE | ID: mdl-26774117

RESUMO

Growth differentiation factor 11 (GDF11) is member of the transforming growth factor ß (TGF-ß) superfamily of proteins. Circulating GDF11 concentrations appear to decline with age, and its depletion is associated with cardiac hypertrophy and other morbidities. Knowledge of GDF11 regulation is limited, and the effects of natural genetic variation on GDF11 levels are currently undefined. We tested whether genetic background determines serum GDF11 concentrations using two classical inbred mouse strains: C57BL/6J (B6) and BALB/cByJ (BALB). B6 mice exhibited significantly higher GDF11 levels than BALB mice, and these strain differences were consistent throughout the life span. Overall, interactions between age and genetic background determined GDF11 concentrations, which were unaffected by sex. We then surveyed a panel of 22 genetically diverse inbred mouse strains and discovered a sixfold range in GDF11 levels at middle age. We estimated that 74.52% of phenotypic variation in GDF11 levels was attributable to genetic background. We used the Mouse Phenome Database to screen for phenotypes that correlate with GDF11. Interestingly, GDF11 levels predicted median strain life spans. This study revealed high heritability of GDF11 levels. Furthermore, our correlative data suggest that GDF11 may serve as a novel predictor of mammalian life span.


Assuntos
Envelhecimento/sangue , Fatores de Diferenciação de Crescimento/sangue , Fatores de Diferenciação de Crescimento/genética , Longevidade/genética , Animais , Biomarcadores/sangue , Proteínas Morfogenéticas Ósseas , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Masculino , Camundongos , Camundongos Endogâmicos C57BL
9.
Chin Med J (Engl) ; 129(1): 54-8, 2016 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-26712433

RESUMO

BACKGROUND: Trichophyton rubrum represents the most common infectious fungus responsible for dermatophytosis in human, but the mechanism involved is still not completely understood. An appropriate model constructed to simulate host infection is the prerequisite to study the pathogenesis of dermatophytosis caused by T. rubrum. In this study, we intended to develop a new T. rubrum infection model in vitro, using the three-dimensional reconstructed epidermis - EpiSkin ®, and to pave the way for further investigation of the mechanisms involved in T. rubrum infection. METHODS: The reconstructed human epidermis (RHE) was infected by inoculating low-dose (400 conidia) and high-dose (4000 conidia) T. rubrum conidia to optimize the infection dose. During the various periods after infection, the samples were processed for pathological examination and scanning electron microscopy (SEM) observation. RESULTS: The histological analysis of RHE revealed a fully differentiated epidermis with a functional stratum corneum, which was analogous to the normal human epidermis. The results of hematoxylin and eosin staining and the periodic acid-Schiff staining showed that the infection dose of 400 conidia was in accord with the pathological characteristics of host dermatophytosis caused by T. rubrum. SEM observations further exhibited the process of T. rubrum infection in an intuitionistic way. CONCLUSIONS: We established the T. rubrum infection model on RHE in vitro successfully. It is a promising model for further investigation of the mechanisms involved in T. rubrum infection.


Assuntos
Epiderme/microbiologia , Queratinócitos/citologia , Trichophyton/patogenicidade , Animais , Modelos Animais de Doenças , Humanos , Técnicas de Cultura de Tecidos
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