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1.
Am J Pathol ; 192(4): 712-721, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35063407

RESUMO

Although glycolysis plays a pivotal role in breast cancer stem-like cell (BCSC) reprogramming, the molecular mechanisms that couple glycolysis to cancer stem-like cells remain unclear. SETD5 is a previously uncharacterized member of the histone lysine methyltransferase family. The goal of this study was to explore the mechanisms underlying the promotion of stem-like and glycolysis activation traits by SETD5. Previous studies have shown that overexpression of SETD5 in breast cancer tissues is associated positively with progression. The present study showed that SETD5 expression was enriched in BCSCs. Down-regulation of SETD5 significantly decreased BCSC properties and glycolysis in vitro and in vivo. Interestingly, SETD5 and glycolytic enzymes were accumulated in the central hypoxic regions of subcutaneous tumor tissues. Bioinformatic analysis predicted SETD5 binding to E1A binding protein p300 (EP300), and subsequently to hypoxia-inducible factor 1α (HIF-1α). The mechanistic study found that SETD5 is an upstream effector of EP300/HIF-1α. SETD5 knockdown reduced the expression of HIF-1α, hexokinase-2, and 6-phosphofructo-2-kinase in the nucleus after treatment with cobalt chloride, a chemical hypoxia mimetic agent that activates HIF-1α to accumulate in the nucleus. Therefore, SETD5 is required for glycolysis in BCSCs through binding to EP300/HIF-1α and could be a potential therapeutic target for breast cancer patients.


Assuntos
Neoplasias da Mama , Metiltransferases , Células-Tronco Neoplásicas , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Regulação para Baixo , Feminino , Glicólise/fisiologia , Humanos , Hipóxia/patologia , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Metiltransferases/metabolismo , Células-Tronco Neoplásicas/patologia
2.
Am J Pathol ; 191(1): 180-193, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33129761

RESUMO

Several studies have confirmed the function of Su(var)3-9, Enhancer of zeste, and Trithorax (SET) domain-containing 5 (SETD5) in post-translational modifications of nonhistone proteins. Mutation of the SETD5 gene has been implicated in the progression of many human cancers, such as breast cancer (BC), but its functional role in BC progression is still unknown. The current article investigates the clinical significance and the functional role of SETD5 in BC. Our studies show that SETD5 expression in BC was related to poor clinical outcomes, including lymph node metastasis and advanced clinical stage. SETD5 expression positively correlated with tumor-associated macrophages. SETD5 was an independent predictor of poor overall survival in BC. Furthermore, these studies show that down-regulation of SETD5 significantly decreased BC cell proliferation, metastasis, and angiogenesis, and increased apoptosis of BC cells. The mechanistic analysis showed that SETD5 contributes BC progression by interacting with AKT1 pathway. Also, in vivo experiments show that blocking of SETD5 expression significantly inhibited tumor growth and pulmonary metastasis of BC cells. These findings indicate that SETD5 is a potential prognosis marker and facilitates tumor progression of BC.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Regulação Neoplásica da Expressão Gênica/fisiologia , Metiltransferases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Biomarcadores Tumorais/metabolismo , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/metabolismo , Proliferação de Células/fisiologia , Progressão da Doença , Feminino , Xenoenxertos , Humanos , Neoplasias Pulmonares/secundário , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Invasividade Neoplásica/patologia , Transdução de Sinais/fisiologia , Regulação para Cima
3.
Environ Monit Assess ; 195(1): 224, 2022 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-36562885

RESUMO

Considering the spatio-temporal heterogeneity, this study resolved the coupling influence of a variety of driving factors on vegetation changes in mining areas and discovered the influencing characteristics of the respective driving factors, especially mining activities. First, the spatio-temporal characteristics of FVC (fractional vegetation cover) variation were analyzed in the Sheng-Li mining area. Second, the quantitative relationships among the natural factors (temperature, precipitation, and elevation), artificial factors (mining activities, urban activities), and FVC were constructed by GTWR (geographically and temporally weighted regression) to quantify the contribution of each factor to the change in FVC. Third, the influencing characteristics of the respective driving factors, especially mining activities, were analyzed and summarized. The results show that (1) the FVC change was mainly influenced by natural factors in the areas far from mines and towns and artificial factors in the areas close to mines and towns. (2) The contribution of mining activities to vegetation change (C-Mine) was spatially characterized by two features: (a) distance attenuation characteristics: C-Mine showed logarithmic decrement with distance; (b) directional heterogeneity: C-Mine varied significantly in different directions. In particular, there was a high C-Mine area located near multiple mining areas, and the range of this area shifted to include the mine with more production over time. Overall, unmixing the coupling influence from driving factors with spatio-temporal heterogeneity and achieving a quantitative description of the influencing characteristics in mining areas were the main contributions of this study. The quantification methods and results in this paper provide important support for decision-making on ecological protection and restoration in mining areas.


Assuntos
Monitoramento Ambiental , Mineração , China , Ecossistema
4.
J Cell Mol Med ; 25(4): 2110-2120, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33314691

RESUMO

Leucine zipper-EF-hand-containing transmembrane protein 1 (LETM1) is a mitochondrial inner membrane protein that is highly expressed in various cancers. Although LETM1 is known to be associated with poor prognosis in colorectal cancer (CRC), its roles in autophagic cell death in CRC have not been explored. In this study, we examined the mechanisms through which LETM1 mediates autophagy in CRC. Our results showed that LETM1 was highly expressed in CRC tissues and that down-regulation of LETM1 inhibited cell proliferation and induced S-phase arrest. LETM1 silencing also suppressed cancer stem cell-like properties and induced autophagy in CRC cells. Additionally, the autophagy inhibitor 3-methyladenine reversed the inhibitory effects of LETM1 silencing on proliferation and stemness, whereas the autophagy activator rapamycin had the opposite effects. Mechanistically, suppression of LETM1 increased the levels of reactive oxygen species (ROS) and mitochondrial ROS by regulation of SOD2, which in turn activated AMP-activated protein kinase (AMPK)/mammalian target of rapamycin (mTOR), initiated autophagy, and inhibited proliferation and stemness. Our findings suggest that silencing LETM1 induced autophagy in CRC cells by triggering ROS-mediated AMPK/mTOR signalling, thus blocking CRC progression, which will enhance our understanding of the molecular mechanism of LETM1 in CRC.


Assuntos
Autofagia , Proteínas de Ligação ao Cálcio/genética , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Regulação Neoplásica da Expressão Gênica , Proteínas de Membrana/genética , Células-Tronco Neoplásicas/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Biomarcadores , Proteínas de Ligação ao Cálcio/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/patologia , Inativação Gênica , Humanos , Imunofenotipagem , Proteínas de Membrana/metabolismo , Mitocôndrias/genética , Mitocôndrias/metabolismo , Modelos Biológicos , Transdução de Sinais , Serina-Treonina Quinases TOR/metabolismo
5.
Cancer Cell Int ; 20: 122, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32322169

RESUMO

BACKGROUND: Tenascin-C (TNC) is an extracellular matrix protein that is widely expressed in the stromal fibroblasts of various cancers. However, the roles of TNC in colorectal cancer (CRC) cells remain unclear. METHODS: The expression of TNC, cancer stem cell-like (CSC) and cell cycle markers, and Hedgehog (HH) signaling pathway genes were assessed in 100 paraffin embedded clinical CRC patient tissues using immunohistochemistry. The interaction between TNC and CSC marker or HH related genes in CRC cells were detected by immunofluorescence. Cell cycle distribution was measured by flow cytometry. Migration and invasion were evaluated by transwell assays. The expressions of TNC, CSC marker, and HH related proteins were analyzed by western blot. RESULTS: TNC expression was markedly upregulated in CRC tissues, and was associated with worse clinical outcomes. TNC overexpression was positively associated with CSC marker LSD1, cell cycle markers CDK4 and p16, and HH signaling pathway related genes SMO and GLI1 in clinical CRC tissue samples. TNC silencing downregulated the expression of the CSC marker LSD1, and the proliferation, migration, and invasion of CRC cells. Interestingly, the GLI1 inhibitor GANT61 strongly inhibited the expression of TNC in CRC cells. CONCLUSIONS: TNC may drive tumor progression and is involved in CSC properties via the HH signaling pathway. TNC has potential value in the evaluation of poor prognosis in CRC.

6.
BMC Cancer ; 19(1): 898, 2019 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-31500591

RESUMO

BACKGROUND: Although the leucine zipper-EF-hand-containing transmembrane protein 1 (LETM1) is one of the mitochondrial inner membrane proteins that is involved in cancer prognosis in various tumors, LETM1 as a biomarker for prognostic evaluation of non-small cell lung carcinoma (NSCLC) has not been well studied. METHODS: To address this issue, we used 75 cases NSCLC, 20 cases adjacent normal lung tissues and NSCLC cell lines. We performed immunohistochemistry staining and western blot analysis as well as immunofluorescence imaging. RESULTS: Our studies show that expression of LETM1 is significantly correlated with the lymph node metastasis (p = 0.003) and the clinical stage (p = 0.005) of NSCLC. The Kaplan-Meier survival analysis revealed that NSCLC patients with positive expression of LETM1 exhibits a shorter overall survival (OS) rate (p = 0.005). The univariate and multivariate Cox regression analysis indicated that LETM1 is a independent poor prognostic marker of NSCLC. In addition, the LETM1 expression is correlated with cancer stemness-related gene LGR5 (p < 0.001) and HIF1α expression (p < 0.001), but not with others. Moreover, LETM1 expression was associated with the expression of cyclin D1 (p = 0.003), p27 (p = 0.001), pPI3K(p85) (p = 0.025), and pAkt-Thr308 (p = 0.004). Further, our studies show in LETM1-positive NSCLC tissues the microvessel density was significantly higher than in the negative ones (p = 0.024). CONCLUSION: These results indicate that LETM1 is a potential prognostic biomarker of NSCLC.


Assuntos
Proteínas de Ligação ao Cálcio/análise , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Neoplasias Pulmonares/metabolismo , Proteínas de Membrana/análise , Idoso , Biomarcadores Tumorais/análise , Proteínas de Ligação ao Cálcio/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/análise , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/genética , Masculino , Proteínas de Membrana/genética , Pessoa de Meia-Idade , Prognóstico , Receptores Acoplados a Proteínas G/análise , Receptores Acoplados a Proteínas G/genética
7.
Exp Mol Pathol ; 109: 104239, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30904401

RESUMO

Although tenascin-C (TNC), an extracellular matrix protein, has been shown to be widely expressed in stromal fibroblasts in various cancers, the role of its expression in esophageal squamous cell carcinoma (ESCC) cells remains unclear. Using immunohistochemistry, we investigated the expression of cancer stem-like cell (CSC) markers, epithelial-to-mesenchymal transition (EMT)-related genes, and the Akt/hypoxia-inducible factor-1α (HIF1α) signal pathway in ESCC tissue specimens from 154 patients. We further addressed the effects of TNC on the Akt/HIF1α axis and its putative association with cancer stemness in several ESCC cell lines by immunofluorescence imaging and western blot analysis. Our data suggest that TNC expression was positively correlated with the expression of the CSC marker SOX2 (p = .002), and TNC-expressing cancer cells expressed SOX2 in ESCC tissues. Moreover, TNC expression was strongly associated with EMT-related gene Snail (p = .022) and positively correlated with pAkt-Ser473 (p = .004) and HIF1α (p = .003). Furthermore, TNC-silencing down-regulated the expression of CSC marker SOX2 (p < .001) and EMT-related marker Snail (p < .001). The Akt inhibitor Perifosine inhibited the protein expression of pAkt-Ser473, Akt, HIF1α, and TNC in TE10 (an ESCC cell line) cells. Short-term exposure of TE10 cells to cobalt chloride caused an increase in protein expression of HIF1α, TNC, and SOX2 in a time-dependent manner. Taken together, these results suggest that TNC may enhance the cancer stem-like properties and promote EMT-like changes via the Akt/HIF1α axis.


Assuntos
Neoplasias Esofágicas/metabolismo , Carcinoma de Células Escamosas do Esôfago/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Células-Tronco Neoplásicas/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Tenascina/metabolismo , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Intervalo Livre de Doença , Transição Epitelial-Mesenquimal/genética , Neoplasias Esofágicas/genética , Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/genética , Carcinoma de Células Escamosas do Esôfago/patologia , Regulação Neoplásica da Expressão Gênica , Humanos , Imuno-Histoquímica , Células-Tronco Neoplásicas/patologia , Interferência de RNA , Transdução de Sinais , Tenascina/genética
8.
Exp Cell Res ; 373(1-2): 145-154, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30321514

RESUMO

The role of Hedgehog (HH)/ glioma-associated oncogene homolog 1 (GLI1) pathway has been implicated in a variety of cancer entities, and the targeted pathway inhibition mediated by GLI1 is of therapeutic relevance. However, its oncogenicity and cross-talks with other cancer pathways including PI3K/Akt/NFκB, which modulates the HH/GLI1 signal strength, have rarely been explored in colorectal adenocarcinoma. We assessed the expression of GLI1 and its relationship with other cancer stemness genes, cell cycle markers, epithelial-mesenchymal transition (EMT), PI3K/Akt/NFκB signaling pathway genes, and HIF1α in 100 paraffin-embedded colorectal adenocarcinoma tissue samples using immunohistochemistry. We further addressed the effect of GLI1 on EMT, cell cycle, and its putative interaction with the PI3K/Akt/NFκB cascade in colorectal adenocarcinoma cell lines. The expression of GLI1 in colorectal adenocarcinoma tissues was found to correlate with the clinical stages, and distant metastasis. Moreover, GLI1 was found to be an independent predictor of poor overall survival and disease-free survival in colorectal adenocarcinoma. GLI1-expressing cancer cells also expressed their representative cancer stem-like cell (CSC) markers (SOX9 and CD133), as well as HIF1α. GLI1 expression was also strongly linked to EMT-related and PI3K/Akt/NFκB signaling genes. Downregulation of GLI1 by inhibitor treatment in colorectal adenocarcinoma cell lines resulted in reduced expression of CSC markers, cell clonogenicity, S-phase subpopulations, as well as the migration and invasion ability. Importantly, Akt inhibitor Perifosine significantly inhibited the expression of pAkt and GLI1 in colorectal adenocarcinoma cells. Combination of GLI1 inhibitor GANT61 and NFκB p65 inhibitor QZN exhibited much higher inhibition compared to using any of them individually on colorectal adenocarcinoma cells. We suggested that GLI1 may be a novel stem cell marker, and cancer stemness was activated via PI3K/Akt/NFκB pathway. In addition, co-targeting GLI1 and PI3K/Akt/NFκB signaling simultaneously might provide an alternative therapeutic strategy for colorectal adenocarcinoma patients.


Assuntos
Adenocarcinoma/metabolismo , Neoplasias Colorretais/metabolismo , Células-Tronco Neoplásicas/metabolismo , Transdução de Sinais , Proteína GLI1 em Dedos de Zinco/metabolismo , Adenocarcinoma/enzimologia , Adenocarcinoma/patologia , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/patologia , Transição Epitelial-Mesenquimal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , NF-kappa B/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo
9.
J Orthop Sci ; 24(4): 731-736, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30638689

RESUMO

PURPOSE: Bioactive glass-ceramic (BGC) coatings have been extensively studied and clinically used as bone substitute materials because of their osteogenesis, osteoinduction, and osteoconduction characteristics. Although the Hedgehog (Hh) signaling pathway plays an important role in skeletal development, the relationship between BGC coatings and the Hh signaling pathway is unknown. METHODS: In this study, a BGC coating is fabricated by furnace sintering, and its surface is investigated by a scanning electron microscope (SEM) and a transmission electron microscope (TEM). Furthermore, the expression of Ki67 is evaluated using immunofluorescence, and osteogenesis-related factors and Hh signaling pathway molecules on the BGC coating are examined by real-time reverse transcription polymerase chain reaction (real-time RT-PCR) and Western blotting in bone marrow mesenchymal stem cells (BMSCs). RESULTS: The SEM and the TEM show that the BGC coating surface is smooth, without cracks, and composed of particles with mesoporous structure. The expression of Ki67 positive BMSCs of the BGC group is higher than that of the control group. Real-time RT-PCR and Western blotting assay reveal that the expression levels of osteoblast-related genes (BMP2, Osteocalcin, ALP, Runx2) and Hh signaling pathway molecules (Gli1, Smo) are much higher for the BGC coating group than those for the control group. Furthermore, after treating with Smo inhibitor cyclopamine, the Smo and Gli1 expressions in BMSCs are dramatically down-regulation for the BGC coating compared to those for the control group. Both mRNA and protein expression levels of osteogenesis-related factors was downregulated after treating Smo inhibitor cyclopamine in BMSCs with the BGC coating. CONCLUSIONS: The BGC coatings promote osteogenesis probably via the Hh signaling pathway, which provides a theory reference for future clinical application of bone formation.


Assuntos
Cerâmica , Materiais Revestidos Biocompatíveis , Proteínas Hedgehog/fisiologia , Células-Tronco Mesenquimais/fisiologia , Osteogênese/fisiologia , Transdução de Sinais/fisiologia , Técnicas de Cultura de Células , Humanos
11.
Zhongguo Dang Dai Er Ke Za Zhi ; 21(4): 317-322, 2019 Apr.
Artigo em Zh | MEDLINE | ID: mdl-31014421

RESUMO

OBJECTIVE: To investigate the causes and clinical features of children with traumatic brain injury (TBI) who need hospitalization or emergency observation. METHODS: A retrospective analysis was performed for the clinical data of 126 children with TBI who were admitted to the emergency department from January 1, 2014 to August 31, 2016, including causes of injury and clinical features. RESULTS: Of the 126 children, there were 95 boys and 31 girls, with a mean age of 2.8 years (range 0.8-5.5 years). The children aged <1 year accounted for 38.1% (48/126), and 26 children died. The two most common types of TBI were epidural hematoma (54.0%) and subarachnoid hemorrhage (50.8%). Of the 126 children, 83 (65.9%) had a Glasgow Coma Scale score of ≤8 within 24 hours after admission. There were different causes of TBI and places where TBI occurred in different age groups. The two leading causes of TBI were falls (51.6%) and road traffic injuries (42.9%). Compared with those in the other age groups, the children in the age <1 year group were most likely to experience injury due to falls (46%; P=0.023). Thirty-five percent of all TBI due to road traffic injuries occurred in the children aged 3-6 years (P<0.001). Most TBI cases occurred at home (47.6%) or on roads/streets (45.2%). Among those who experienced TBI at home, the children aged <1 year accounted for the highest proportion of 48% (P=0.002), and 53% of the patients aged 3-6 years experienced TBI on roads/streets. The most common cause of death in children with TBI was road traffic injury, which accounted for 69%. Among those who died, the children aged <1 year accounted for the highest proportion (62%). CONCLUSIONS: There are different causes of TBI and places where TBI occurs in different age groups. Among children with TBI, the children aged <1 year account for the highest proportion and have the highest number of deaths, with falls at home as the most common cause of TBI. Children aged 3-6 years tend to suffer TBI due to road traffic injury. Road traffic injury is the leading cause of death.


Assuntos
Lesões Encefálicas Traumáticas , Criança , Pré-Escolar , Feminino , Escala de Coma de Glasgow , Hospitalização , Humanos , Masculino , Estudos Retrospectivos
12.
Exp Mol Pathol ; 105(2): 216-222, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30170017

RESUMO

Although Tenascin-C (TNC) as an extracellular matrix protein involved in various cancers, the mechanisms by which TNC leads to decreased survival time remain to be clarified in CRC. We assessed the expression of TNC and its relationship with cancer associated fibroblasts (CAFs) markers, epithelial-to-mesenchymal transition (EMT) and cell cycle markers in 100 paraffin-embedded CRC tissue samples using immunohistochemistry. TNC expression was higher in CRC tissue samples than in adjacent non-tumor-tissues (P < .001). In addition, TNC was involved in clinical stage (P = .030), pT stage (P = .049), distant metastasis (P = .004), tumor recurrence (P = .007), and tumor budding (P < .001). TNC play crucial roles in regulating the poor 5-year CRC survival rate by Kaplan-Meier analysis, and was an independent predictor of poor overall survival (P = .007) and disease-free survival (P = .004) in CRC. Moreover, it was postively correlated with CAF (SMA (P < .001) and FSP1 (P = .005)) and cell cycle marker p27 (P = .013) along with EMT (E-cadherin, P = .599; Snail, P < .001; vimentin, P = .012). TNC may promote EMT-like change and proliferation, which lead to poor prognosis for patients with CRC.


Assuntos
Neoplasias Colorretais/genética , Tenascina/metabolismo , Adulto , Idoso , Biomarcadores Tumorais , Caderinas/metabolismo , Proliferação de Células/genética , China , Neoplasias do Colo/metabolismo , Neoplasias Colorretais/metabolismo , Intervalo Livre de Doença , Transição Epitelial-Mesenquimal/genética , Matriz Extracelular/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Feminino , Fibroblastos , Humanos , Imuno-Histoquímica , Estimativa de Kaplan-Meier , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/metabolismo , Prognóstico , Tenascina/análise , Tenascina/genética
13.
J Opt Soc Am A Opt Image Sci Vis ; 32(12): 2409-22, 2015 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-26831395

RESUMO

Photometric correction and reflectance calculation are two important processes in the scientific analysis and application of Chang'E-1 (CE-1) charge-coupled device (CCD) stereo camera data. In this paper, the methods of photometric correction and reflectance calculation were developed. On the one hand, in considering the specificity of datasets acquired by the CE-1 CCD stereo camera, photometric correction was conducted based on the digital number value directly using the revised Lommel-Seeliger factor. On the other hand, on the basis of laboratory-measured bidirectional reflectances, the relative reflectance was then calculated using the empirical linear model. The presented approach can be used to identify landing sites, obtain global images, and produce topographic maps of the lunar surface.

14.
Sex Transm Dis ; 41(2): 98-102, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24413488

RESUMO

OBJECTIVE: The present study aimed to estimate the prevalence of syphilis among men who have sex with men (MSM) currently married with women in cities of China and examine the related factors for syphilis among them. METHODS: "Snowballing" sampling was used to recruit participants in 4 cities from April 2008 to August 2009. Information of participants was collected anonymously and remained confidential. Blood samples were collected from all eligible participants for HIV and syphilis tests. RESULTS: A total of 858 men participated in the study, and their average age was 38.3 years (ranged from 21 to 75 years). Fifty-three percent did not have residence cards, 37% accepted junior high school education or less, and 41% identified themselves as gay. The prevalence of HIV and syphilis was 8.0% and 17.9%, respectively. Older age, less education, homosexual orientation, the sex of the first sexual partner, residential places, and HIV infection were significantly associated with syphilis infection. Gay had higher proportions of some risk sexual behaviors than did non-gay-identified participants, including the first insert sex before 18 years (17.9% vs. 13.0%), the first male sex partner (49.0% vs. 34.3%) anal sex in the last 6 months (88.0% vs. 83.0%), noncondom use in the last anal sex (35.9% vs. 28.0%), and never use condom in anal sex in the last 6 months (14.8% vs. 9.1%). Non-gay-identified participants had a higher proportion of having opposite sex than did gay participants (70.8% vs. 43.0%). CONCLUSIONS: Currently married MSM had a high prevalence of syphilis, and preventive interventions should be developed to control syphilis transmissions among currently married MSM via extromarital sex and intromarital opposite sex.


Assuntos
Bissexualidade , Preservativos/estatística & dados numéricos , Relações Extramatrimoniais , Soropositividade para HIV/transmissão , Homossexualidade Masculina , Parceiros Sexuais , Sífilis/etiologia , Adulto , Fatores Etários , Idoso , China/epidemiologia , Estudos Transversais , Escolaridade , Feminino , Soropositividade para HIV/imunologia , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , Assunção de Riscos , Vigilância de Evento Sentinela , Sífilis/imunologia , Sífilis/prevenção & controle , Sífilis/transmissão
15.
Guang Pu Xue Yu Guang Pu Fen Xi ; 34(4): 1060-3, 2014 Apr.
Artigo em Zh | MEDLINE | ID: mdl-25007629

RESUMO

UV-Vis absorption spectra and electrochemical properties of 5-(o-hydroxyphenyl)-10, 15, 20-tri-(p-phenyl)porphyrin (TPPOH) and 5-(o-hydroxyphenyl)-10, 15, 20-tri-(p-methoxyphenyl) porphyrin [(p-OCH3)TPPOH] with different electron groups were investigated by experiments and density functional theory (DFT). Due to the introduction of para-methoxyl group (-OCH3), obvious red shift of 3 nm in the maximum absorbance of the UV-Vis spectra, negative shift in redox potential of (p-OCH3)TPPOH, and the decrease (0.06 eV) in the energy gap (DE) of the frontier highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) (of (p-OCH3)TPPOH occurred as compared to those of TPPOH. The results are due to that electron donating groups of -OCH3 increase the electron density of porphyrin ring in (p-OCH3)TPPOH. Electron distributions of the frontier orbital calculated by DFT showed that the increase in the energy levels of HOMO and LUMO, while the decrease of 0.05 eV in the energy gap. The agreement between experimental result and theoretical value and the further illustration of the mechanism for the spectral change and electrochemical properties provide important bases for the design and application of the porphyrin derivatives with different electron groups.

16.
IEEE Trans Cybern ; PP2024 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-39037879

RESUMO

Policy iteration (PI), an iterative method in reinforcement learning, has the merit of interactions with a little-known environment to learn a decision law through policy evaluation and improvement. However, the existing PI-based results for output-feedback (OPFB) continuous-time systems relied heavily on an initial stabilizing full state-feedback (FSFB) policy. It thus raises the question of violating the OPFB principle. This article addresses such a question and establishes the PI under an initial stabilizing OPFB policy. We prove that an off-policy Bellman equation can transform any OPFB policy into an FSFB policy. Based on this transformation property, we revise the traditional PI by appending an additional iteration, which turns out to be efficient in approximating the optimal control under the initial OPFB policy. We show the effectiveness of the proposed learning methods through theoretical analysis and a case study.

17.
Sci Rep ; 14(1): 13479, 2024 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-38867075

RESUMO

Surface coal development activities include mining and ecological restoration, which significantly impact regional carbon sinks. Quantifying the dynamic impacts on carbon sequestration in vegetation (VCS) during coal development activities has been challenging. Here, we provided a novel approach to assess the dynamics of VCS affected by large-scale surface coal mining and subsequent restoration. This approach effectively overcomes the limitations imposed by the lack of finer scale and long-time series data through scale transformation. We found that mining activities directly decreased VCS by 384.63 Gg CO2, while restoration activities directly increased 192.51 Gg CO2 between 2001 and 2022. As of 2022, the deficit in VCS at the mining areas still had 1966.7 Gg CO2. The study highlights that complete restoration requires compensating not only for the loss in the year of destruction but also for the ongoing accumulation of losses throughout the mining lifecycle. The findings deepen insights into the intricate relationship between coal resource development and ecological environmental protection.

18.
Sci Data ; 11(1): 689, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926386

RESUMO

Coal is one of the most important fossil energy sources and is ensuring global energy security. Annual maximum NDVI (Normalized Difference Vegetation Index) data is an important indicator for the research in balancing coal mining and vegetation conservation. However, the existing annual maximum NDVI data displayed lower values with temporally inconsistent and a noticeable mosaic line. Here we propose an algorithm for automatically generating the annual maximum NDVI of China's coal bases in Google Earth Engine called: Auto-NDVIcb. The accuracy of the Auto-NDVIcb algorithm has been verified with an average RMSE of 0.087 for the 14 coal bases from 2013 to 2022. Based on the proposed Auto-NDVIcb algorithm, an annual maximum NDVI dataset for all 14 coal bases in China from 2013 to 2022 was publicly released. This dataset can be fast and automatically updated online. Hence, the public dataset will continuously serve to monitor the vegetation change induced by coal mining, exploring the mechanism of vegetation degradation, and providing scientific data for developing vegetation protection policies in coal mines.

19.
mSystems ; 9(3): e0121423, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38364095

RESUMO

The intestine plays a pivotal role in nutrient absorption and host defense against pathogens, orchestrated in part by antimicrobial peptides secreted by Paneth cells. Among these peptides, lysozyme has multifaceted functions beyond its bactericidal activity. Here, we uncover the intricate relationship between intestinal lysozyme, the gut microbiota, and host metabolism. Lysozyme deficiency in mice led to altered body weight, energy expenditure, and substrate utilization, particularly on a high-fat diet. Interestingly, these metabolic benefits were linked to changes in the gut microbiota composition. Cohousing experiments revealed that the metabolic effects of lysozyme deficiency were microbiota-dependent. 16S rDNA sequencing highlighted differences in microbial communities, with ASTB_g (OTU60) highly enriched in lysozyme knockout mice. Subsequently, a novel bacterium, ASTB Qing110, corresponding to ASTB_g (OTU60), was isolated. Metabolomic analysis revealed that ASTB Qing110 secreted high levels of NAD+, potentially influencing host metabolism. This study sheds light on the complex interplay between intestinal lysozyme, the gut microbiota, and host metabolism, uncovering the potential role of ASTB Qing110 as a key player in modulating metabolic outcomes. IMPORTANCE: The impact of intestinal lumen lysozyme on intestinal health is complex, arising from its multifaceted interactions with the gut microbiota. Lysozyme can both mitigate and worsen certain health conditions, varying with different scenarios. This underscores the necessity of identifying the specific bacterial responses elicited by lysozyme and understanding their molecular foundations. Our research reveals that a deficiency in intestinal lysozyme1 may offer protection against diet-induced obesity by altering bacterial populations. We discovered a strain of bacterium, ASTB Qing110, which secretes NAD+ and is predominantly found in lyz1-deficient mice. Qing110 demonstrates positive effects in both C. elegans and mouse models of ataxia telangiectasia. This study sheds light on the intricate role of lysozyme in influencing intestinal health.


Assuntos
Microbiota , Muramidase , Animais , Camundongos , Muramidase/genética , NAD , Caenorhabditis elegans , Intestinos/microbiologia , Bactérias , Dieta Hiperlipídica/efeitos adversos
20.
Artigo em Inglês | MEDLINE | ID: mdl-36834465

RESUMO

Understanding the synergistic effect between topography and vegetation in the underground coal mine is of great significance for the ecological restoration and sustainable development of mining areas. This paper took advantage of unmanned aerial vehicle (UAV) remote sensing to obtain high-precision topographic factors (i.e., digital elevation model (DEM), slope, and aspect) in the Shangwan Coal Mine. Then, a normalized difference vegetation index (NDVI) was calculated utilizing Landsat images from 2017 to 2021, and the NDVI with the same spatial resolution as the slope and aspect was acquired by down-sampling. Finally, the synergistic effect of topography and vegetation in the underground mining area was revealed by dividing the topography obtained using high-precision data into 21 types. The results show that: (1) the vegetation cover was dominated by "slightly low-VC", "medium-VC", and "slightly high-VC" in the study area, and there was a positive correlation between the slope and NDVI when the slope was more than 5°. (2) When the slope was slight, the aspect had less influence on the vegetation growth. When the slope was larger, the influence of the aspect increased in the study area. (3) "Rapidly steep-semi-sunny slope" was the most suitable combination for the vegetation growth in the study area. This paper revealed the relationship between the topography and vegetation. In addition, it provided a scientific and effective foundation for decision-making of ecological restoration in the underground coal mine.


Assuntos
Tecnologia de Sensoriamento Remoto , Dispositivos Aéreos não Tripulados , Mineração , Carvão Mineral
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