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1.
FASEB J ; 38(13): e23751, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38923701

RESUMO

Mesenchymal stem cells (MSCs) reveal multifaceted immunoregulatory properties, which can be applied for diverse refractory and recurrent disease treatment including acute graft-versus-host disease (aGVHD). Distinguishing from MSCs with considerable challenges before clinical application, MSCs-derived exosomes (MSC-Exos) are cell-free microvesicles with therapeutic ingredients and serve as advantageous alternatives for ameliorating the outcomes of aGVHD. MSC-Exos were enriched and identified by western blotting analysis, NanoSight, and transmission electron microscopy (TEM). Bone marrow-derived MSCs (denoted as MSCs) and exosomes (denoted as MSC-Exos) were infused into the aGVHD SD-Wister rat model via tail vein, and variations in general growth and survival of rats were observed. The level of inflammatory factors in serum was quantized by enzyme-linked immunosorbent assay (ELISA). The pathological conditions of the liver and intestine of rats were observed by frozen sectioning. The ratios of CD4+/CD8+ and Treg cell proportions in peripheral blood, together with the autophagy in the spleen and thymus, were analyzed by flow cytometry. After treatment with MSC-Exos, the survival time of aGVHD rats was prolonged, the clinical manifestations of aGVHD in rats were improved, whereas the pathological damage of aGVHD in the liver and intestine was reduced. According to ELISA, we found that MSC-Exos revealed ameliorative effect upon aGVHD inflammation (e.g., TNF-α, IL-2, INF-γ, IL-4, and TGF-ß) compared to the MSC group. After MSC-Exo treatment, the ratio of Treg cells in peripheral blood was increased, whereas the ratio of CD4+/CD8+ in peripheral blood and the autophagy in the spleen and thymus was decreased. MSC-Exos effectively suppressed the activation of immune cells and the manifestation of the inflammatory response in the aGVHD rat model. Our data would supply new references for MSC-Exo-based "cell-free" biotherapy for aGVHD in future.


Assuntos
Exossomos , Doença Enxerto-Hospedeiro , Células-Tronco Mesenquimais , Animais , Exossomos/metabolismo , Doença Enxerto-Hospedeiro/terapia , Ratos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Ratos Wistar , Masculino , Ratos Sprague-Dawley , Transplante de Células-Tronco Mesenquimais/métodos , Linfócitos T Reguladores/imunologia , Células da Medula Óssea/citologia , Autofagia
2.
Int J Cancer ; 155(1): 27-39, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38430541

RESUMO

Information about the NMR metabolomics landscape of overall, and common cancers is still limited. Based on a cohort of 83,290 participants from the UK Biobank, we used multivariate Cox regression to assess the associations between each of the 168 metabolites with the risks of overall cancer and 20 specific types of cancer. Then, we applied LASSO to identify important metabolites for overall cancer risk and obtained their associations using multivariate cox regression. We further conducted mediation analysis to evaluate the mediated role of metabolites in the effects of traditional factors on overall cancer risk. Finally, we included the 13 identified metabolites as predictors in prediction models, and compared the accuracies of our traditional models. We found that there were commonalities among the metabolic profiles of overall and specific types of cancer: the top 20 frequently identified metabolites for 20 specific types of cancer were all associated with overall cancer; most of the specific types of cancer had common identified metabolites. Meanwhile, the associations between the same metabolite with different types of cancer can vary based on the site of origin. We identified 13 metabolic biomarkers associated with overall cancer, and found that they mediated the effects of traditional factors. The accuracies of prediction models improved when we added 13 identified metabolites in models. This study is helpful to understand the metabolic mechanisms of overall and a wide range of cancers, and our results also indicate that NMR metabolites are potential biomarkers in cancer diagnosis and prevention.


Assuntos
Metabolômica , Neoplasias , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Biomarcadores Tumorais/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Metaboloma , Metabolômica/métodos , Neoplasias/epidemiologia , Neoplasias/metabolismo , Modelos de Riscos Proporcionais , Estudos Prospectivos , Biobanco do Reino Unido , Reino Unido/epidemiologia
3.
BMC Infect Dis ; 24(1): 827, 2024 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-39143458

RESUMO

BACKGROUND: There is an increasing number of human immunodeficiency virus (HIV) reported cases among students in Southwest China. However, the data on HIV/sex-related knowledge, attitude toward sex, sexual behaviors, and correlates of pre-exposure prophylaxis (PrEP)-eligible behaviors among college students in this area is still limited. This study aimed to assess the prevalence of HIV/sex-related knowledge, sexual attitudes, sexual behaviors, and factors associated with PrEP-eligible behaviors among college students. METHOD: An online survey from 2020 to 2021 based on a multistage stratified and cluster sampling method was conducted among college students in Southwest China, and a well-designed questionnaire collected data. Propensity score matching (PSM), logistic, and log-binomial regression were used to identify the determinants of PrEP-eligible behaviors. RESULT: A total of 108,987 students participated in the survey, and 92,946 provided valid responses. 91.6% (85,145/92,946) had good HIV-related knowledge, while only 26.0% (24,137/92,946) reported awareness of sex-related knowledge. Furthermore, more than half of the participants (64.5%) held negative stances towards engaging in "one-night stand", and 58.9% (617/1,047) reported PrEP-eligible behaviors. Log-binomial regression analysis indicated that unaware of HIV-related knowledge (aPR = 1.66, 95% CI:1.22-2.26, P = 0.001), not discussing about sex with their parent(s) (aPR = 1.16, 95% CI:1.01-1.33, P = 0.021), not receiving sex-related education in school(aPR = 1.24, 95% CI: 1.07-1.45, P = 0.005), not participating in HIV/AIDS prevention activities in the past year (aPR = 1.32, 95%CI:1.09-1.60, P = 0.004), experiencing forced sex (aPR = 2.08, 95% CI: 1.19-3.63, P = 0.010), and having the drug abuse (aPR = 22.21, 95% CI:5.59-88.31, P < 0.001) were significantly associated with increased odds of PrEP-eligible behaviors. CONCLUSION: College students in Southwest China exhibited suboptimal HIV/sex-related knowledge, received limited sex education, reported conservative attitudes towards casual sex, and significant PrEP-eligible behaviors. These findings suggest that sexually experienced college students who were unaware of HIV-related knowledge, lacked sex education, experienced forced sex, and reported drug abuse were the key individuals for evaluating eligibility for PrEP initiation, and interventions aimed at increasing awareness of HIV/sex-related knowledge, promoting participation in sex education, addressing issues related to forced sex and tackling drug abuse could contribute to reducing the incidence of PrEP-eligible behaviors among college students.


Assuntos
Infecções por HIV , Conhecimentos, Atitudes e Prática em Saúde , Profilaxia Pré-Exposição , Comportamento Sexual , Estudantes , Humanos , Masculino , Feminino , China/epidemiologia , Infecções por HIV/prevenção & controle , Infecções por HIV/epidemiologia , Estudantes/psicologia , Estudantes/estatística & dados numéricos , Estudos Transversais , Adulto Jovem , Comportamento Sexual/estatística & dados numéricos , Universidades , Inquéritos e Questionários , Adolescente , Adulto
4.
Phys Chem Chem Phys ; 26(2): 662-678, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38112019

RESUMO

The photocatalytic performance of nano-TiO2 photocatalysts in air pollutant degradation greatly depends on the adsorption of water, substrates, and intermediates. Especially under excessive humidity, substrate concentration, and intermediate concentration, the competitive adsorption of water, substrates, and intermediates can seriously inhibit the photocatalytic performance. In the past few years, extensive studies have been performed to investigate the influence of humidity, substrate concentration, and intermediates on the photocatalytic performance of TiO2, and significant advances have been made in the area. However, to the best of our knowledge, there is no review focusing on the effects of water, substrate, and intermediate adsorption to date. A comprehensive understanding of their mechanisms is key to overcoming the limited application of nano-TiO2 photocatalysts in the photocatalytic decomposition of air pollutants. In this review, the progress in experimental and theoretical fields, including a recent combination of photocatalytic experiments and adsorption and photocatalytic simulations by density functional theory (DFT), to explore the impact of adsorption of various reaction components on nano-TiO2 photocatalysts is comprehensively summarized. Additionally, the mechanism and broad perspective of the impact of their adsorption on the photocatalytic activity of TiO2 in air treatment are also critically discussed. Finally, several solutions are proposed to resolve the current problems related to environmental factors. In general, this review contributes a comprehensive perspective of water, substrate, and intermediate adsorption toward boosting the photocatalytic application of TiO2 nanomaterials.

5.
BMC Cardiovasc Disord ; 24(1): 365, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39014329

RESUMO

BACKGROUND: M1 macrophages are closely associated with cardiac injury after myocardial infarction (MI). Increasing evidence shows that exosomes play a key role in pathophysiological regulation after MI, but the role of M1 macrophage-derived exosomes (M1-Exos) in myocardial regeneration remains unclear. In this study, we explored the impact of M1 macrophage-derived exosomes on cardiomyocytes regeneration in vitro and in vivo. METHODS: M0 macrophages were induced to differentiate into M1 macrophages with GM-CSF (50 ng/mL) and IFN-γ (20 ng/mL). Then M1-Exos were isolated and co-incubated with cardiomyocytes. Cardiomyocyte proliferation was detected by pH3 or ki67 staining. Quantitative real-time PCR (qPCR) was used to test the level of miR-155 in macrophages, macrophage-derived exosomes and exosome-treated cardiomyocytes. MI model was constructed and LV-miR-155 was injected around the infarct area, the proliferation of cardiomyocytes was counted by pH3 or ki67 staining. The downstream gene and pathway of miR-155 were predicted and verified by dual-luciferase reporter gene assay, qPCR and immunoblotting analysis. IL-6 (50 ng/mL) was added to cardiomyocytes transfected with miR-155 mimics, and the proliferation of cardiomyocytes was calculated by immunofluorescence. The protein expressions of IL-6R, p-JAK2 and p-STAT3 were detected by Western blot. RESULTS: The results showed that M1-Exos suppressed cardiomyocytes proliferation. Meanwhile, miR-155 was highly expressed in M1-Exos and transferred to cardiomyocytes. miR-155 inhibited the proliferation of cardiomyocytes and antagonized the pro-proliferation effect of interleukin 6 (IL-6). Furthermore, miR-155 targeted gene IL-6 receptor (IL-6R) and inhibited the Janus kinase 2(JAK)/Signal transducer and activator of transcription (STAT3) signaling pathway. CONCLUSION: M1-Exos inhibited cardiomyocyte proliferation by delivering miR-155 and inhibiting the IL-6R/JAK/STAT3 signaling pathway. This study provided new insight and potential treatment strategy for the regulation of myocardial regeneration and cardiac repair by macrophages.


Assuntos
Proliferação de Células , Modelos Animais de Doenças , Exossomos , Janus Quinase 2 , Macrófagos , MicroRNAs , Infarto do Miocárdio , Miócitos Cardíacos , Fator de Transcrição STAT3 , Transdução de Sinais , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , Miócitos Cardíacos/efeitos dos fármacos , MicroRNAs/metabolismo , MicroRNAs/genética , Exossomos/metabolismo , Exossomos/transplante , Exossomos/genética , Animais , Proliferação de Células/efeitos dos fármacos , Macrófagos/metabolismo , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT3/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/patologia , Infarto do Miocárdio/fisiopatologia , Infarto do Miocárdio/genética , Janus Quinase 2/metabolismo , Masculino , Regeneração , Ratos Sprague-Dawley , Receptores de Interleucina-6/metabolismo , Receptores de Interleucina-6/genética , Células Cultivadas , Fosforilação , Técnicas de Cocultura , Camundongos Endogâmicos C57BL , Interleucina-6/metabolismo
6.
Appl Opt ; 63(12): 3250-3259, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38856474

RESUMO

We have developed and experimentally investigated a long-range 1.645 µm coherent Doppler wind lidar (CDWL) system. A compact 1.645 µm single-frequency Er:YAG laser is utilized as the laser transmitter. The impact of laser transmitter parameters on wind detection was assessed using the figure of merit (FOM) concept. To enhance the measurement efficiency, the influence of wave aberrations on the heterodyne efficiency was analyzed. A Galilean telescope with an optical aperture of 100 mm is designed as the optical antenna based on the analysis. The line of sight (LOS) detection range exceeds 30.42 km with a data rate of 1 Hz at an elevation angle of 3.5°. To evaluate the effectiveness of the CDWL, comparison experiments were conducted between the 1.645 µm CDWL and a calibrated 1.55 µm CDWL, revealing a correlation coefficient of 0.9816 for the whole detection path in the wind velocity measurement.

7.
BMC Public Health ; 23(1): 1702, 2023 09 04.
Artigo em Inglês | MEDLINE | ID: mdl-37667280

RESUMO

BACKGROUND: The prevalence of human immunodeficiency virus (HIV) is becoming more common among college students in China. However, latest data on the prevalence and correlates of HIV testing among sexually experienced college students is rarely. METHODS: An online survey was conducted among college students aged 18 years or older using multistage stratified cluster sampling from 16 colleges. Data on socio-demographic, HIV testing, HIV-related awareness, attitudes, sexual education and behaviors were collected. Propensity score matching (PSM) and logistic regression model were used to identify factors associated with HIV testing. RESULT: A total of 108,987 students participated the survey, of which 13,201 sexually experienced college students were included in this study. 1,939 (14.69%) college students with sexual experience reported uptake of HIV testing in the preceding year. The uptake of HIV testing increased for college students with a rising HIV knowledge score and sexual health knowledge. Being awareness of HIV-related knowledge (aOR = 1.15, 95%CI: 1.01-1.30), accepting one-night stands (aOR = 1.16, 95%CI:1.03-1.32), obtaining satisfactory sexual interpretation from parent(s) (aOR = 1.24, 95%CI: 1.07-1.43), ever had unintended pregnancy (aOR = 1.78, 95%CI: 1.32-2.38), ever had received HIV-related preventive service(s) (aOR = 1.37, 95%CI: 1.10-1.70), ever had participated HIV-related preventive services (aOR = 3.76, 95%CI: 2.99-4.75) and ever had anal sex (aOR = 2.66, 95%CI: 2.11-3.34) were positively associated with uptake of HIV testing. However, accepting premarital sex (aOR = 0.76, 95%CI: 0.66-0.88), accepting cohabitation (aOR = 0.75, 95%CI: 0.61-0.92), occasionally discussing sex with parent(s) (aOR = 0.68, 95%CI: 0.50-0.91), and being with moderate satisfaction of school sex courses (aOR = 0.74, 95%CI: 0.58-0.95) were negatively associated with uptake of HIV testing. CONCLUSION: The prevalence of HIV testing was relatively low. Participation in HIV-related services and high-risk sexual behaviors were important enablers for testing. Improving sex education for students, increasing HIV preventive services on campus, and improving family sex education are necessary to increase HIV testing among college sexually experienced students.


Assuntos
Infecções por HIV , Comportamento Sexual , Feminino , Gravidez , Humanos , Estudos Transversais , Estudantes , China/epidemiologia , Teste de HIV , Internet , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia
8.
Appl Opt ; 60(34): 10721-10726, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-35200938

RESUMO

A denoising method based on singular value decomposition (SVD) and variational mode decomposition (VMD) is proposed for wind lidar. Utilizing the covariance matrix based lidar signal simulation model, the performance of VMD, SVD, and VMD-SVD is evaluated. The results show that the VMD-SVD method is of better performance, and the output signal-to-noise ratio (SNR) is about 12 dB at the input SNR of -9dB. The actual lidar signals processing is performed with this combined denoising method, and the detection range and wind speed at pulse accumulation numbers of 50,100, and 300 are compared. We set the wind speed resulting from noisy signal with pulse accumulation number of 300 as the reference wind speed, and the mean value and standard deviation of wind differences are analyzed. The results show that the denoising method can not only increase the detection range while ensuring the accuracy of wind speed estimation but also achieve the same detection distance with fewer pulse accumulations, thereby improving the temporal resolution. For the pulse accumulation number of 50, the detection range is extended to 24 km from 18.45 km, and the standard deviation of speed difference is 0.88 m/s; for the same detection range, the temporal resolution is increased by about 6 times.

9.
Neoplasma ; 68(2): 375-381, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33797934

RESUMO

Previous studies have demonstrated that single nucleotide polymorphisms (SNPs) rs12427129 and rs3816153 in HOX transcript antisense intergenic RNA (HOTAIR) might interact with hepatitis B virus (HBV) infection to increase the risk of hepatocellular carcinoma (HCC). However, it is unclear whether HBV infection is a potential mediator between HOTAIR rs12427129, rs3816153, and HCC. This study, including 1262 HCC cases and 1559 controls, aimed to use a four-way decomposition method to quantify the interaction and mediation effects of HBV infection in the association between rs12427129, rs3816153, and HCC. We found that rs12427129 and rs3816153 were associated with a risk of HBV infection among the controls (CC: CT+TT, adjusted odds ratio (OR)=1.77, 95% confidence interval (CI)=1.32-2.36 and GG: GT+TT, adjusted OR=0.63, 95% CI=0.48-0.82). The four-way decomposition revealed that rs12427129, rs3816153, and HBV infection had statistically significant reference interaction on HCC (excess risk (95% CI): -0.362 (-0.530, -0.195), p<0.001 and excess risk (95% CI): 0.433 (0.059, 0.808), p=0.023), and the proportion attributed to reference interaction were 110.82% and 125.27%, respectively. The pure indirect effect suggested that the rs3816153 GT + TT genotype can reduce the risk of HCC by 21.79% (excess risk (95% CI): -0.075 (-0.142, -0.009), p=0.026) when HBV infection as a mediator. Our findings suggested that HBV infection interacts or mediates with the association between rs12427129, rs3816153, and HCC. This would provide a new perspective for exploring the underlying biological mechanism between HOTAIR SNPs, HBV infection, and HCC.


Assuntos
Carcinoma Hepatocelular , Hepatite B Crônica , Neoplasias Hepáticas , RNA Longo não Codificante/provisão & distribuição , Carcinoma Hepatocelular/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Genótipo , Vírus da Hepatite B , Hepatite B Crônica/complicações , Hepatite B Crônica/genética , Humanos , Neoplasias Hepáticas/genética , Polimorfismo de Nucleotídeo Único
10.
Opt Express ; 28(10): 14694-14704, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32403505

RESUMO

Solid-state single-frequency lasers around 1.6 µm are ideal sources for coherent Doppler wind lidars (CDWLs). A CDWL system with 1645 nm sing-frequency, injection-seeded Er:YAG ceramic laser is demonstrated. The Er:YAG laser based on an "M-shaped" ring resonator operates at pulse repetition frequencies (PRFs) of 300-1000 Hz at room temperature. The maximum single-frequency output energy is 10.1 mJ with a pulse width of 179 ns at 300 Hz. The 1645 nm Er:YAG laser is first used in a long-range CDWL system, and a line of sight (LOS) wind velocity up to 25 km is detected with 90 m range resolution in 0.5 s observation. To verify the reliability of the measurement results, the relationship between detection range, pulse energy, and accumulated numbers is also demonstrated.

11.
Mol Carcinog ; 58(5): 633-642, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30556621

RESUMO

HOX transcript antisense intergenic RNA (HOTAIR) has been widely regarded as a functional lncRNA contributing to multiple cancers. However, few studies have examined the effect of single nucleotide polymorphisms (SNPs) in HOTAIR on the occurrence and development of hepatocellular carcinoma (HCC). In this study, three potentially functional HOTAIR SNPs (rs17105613, rs12427129, and rs3816153) were selected using bioinformatic tools. A case-control study including 1262 cases and 1559 controls was conducted to explore the association of HOTAIR SNPs with the risk of HCC in a Southern Chinese population. We found that SNPs rs12427129 and rs3816153 were associated with the risk of HCC in dominant genetic models (CC: CT + TT, adjusted odds ratio (OR) = 0.72, 95% confidence interval (CI) = 0.57-0.90 and GG: GT + TT, adjusted OR = 1.30, 95%CI = 1.08-1.57). Additionally, SNP-environment interactions for rs12427129, rs3816153, and HBsAg status were found to enhance the risk of HCC, with FDR-P as an additive interaction equal to 0.0006 and 0.0144, respectively. In multifactor dimensionality reduction (MDR) analysis, the three-factor model (HBsAg status, rs12427129 and rs3816153) yielded the highest test accuracy of 77.74% (permutation P < 0.001). Interestingly, the effect of rs12427129 and rs3816153 on the risk of HCC could be modified by HBsAg status, while the rs12427129 CT/TT genotype could antagonize the detrimental effect of rs3816153 GT/TT genotype on HCC. Our findings suggest that rs12427129 and rs3816153, including their SNP-SNP and SNP-environment interaction with HBsAg status, potentially play important roles on the susceptibility to HCC.


Assuntos
Povo Asiático/genética , Biomarcadores Tumorais/genética , Carcinoma Hepatocelular/etiologia , Interação Gene-Ambiente , Neoplasias Hepáticas/etiologia , Polimorfismo de Nucleotídeo Único , RNA Longo não Codificante/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Estudos de Casos e Controles , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Antígenos de Superfície da Hepatite B/genética , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco
12.
Int J Cancer ; 142(2): 308-321, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-28921929

RESUMO

The frequently dysregulated Wnt/ß-catenin signaling in different malignancies, by activation of its own or orchestration with other co-factors, regulates various oncogenic or tumor-suppressive genes. Among these genes, miRNAs, which are negative posttranscriptional regulators, are also embedded in the Wnt signaling network. Different from the Wnt-induced oncogenic miRNAs, the specific mechanism underlying the Wnt-repressed tumor-suppressive miRNAs is much less understood. In our study, firstly by analyzing a ChIP-seq dataset against TCF4, the core transcription factor for initiation of Wnt signaling in colorectal cancer (CRC) cells, we screened out several tumor-suppressive miRNAs potentially regulated by Wnt signaling. Then through siRNA-mediated knock-down tests and protein and chromatin immunoprecipitations, we found the TCF4-ß-catenin complex can recruit the histone trimethylation complex PRC2 as a co-repressor while binding to the TCF4-binding element (TBE) in the promoter regions of miR-145, miR-132 and miR-212. Thus, upon Wnt signaling activation, the PRC2-mediated trimethylation of histone H3 at lysine 27 increases at these promoter regions, leading to decreased miRNA levels. Furthermore, we found that by targeting TCF4 and SUZ12, the key components of the negative regulation complexes, the tumor-suppressive miR-145 co-repressed by Wnt signaling and histone trimethylation, forms double-negative regulation loops with its negative regulators in CRC cells. And the inverse associations between miR-145 and its targets/negative regulators have also been demonstrated in nude mice and clinical samples. Collectively, we elucidated the detailed molecular mechanism of how dysregulated Wnt/ß-catenin signaling and tumor-suppressive miRNAs reciprocally regulate each other in CRC cells.


Assuntos
Neoplasias Colorretais/patologia , Regulação Neoplásica da Expressão Gênica , Neoplasias Hepáticas/secundário , MicroRNAs/genética , Complexo Repressor Polycomb 2/metabolismo , Fator de Transcrição 4/metabolismo , beta Catenina/metabolismo , Animais , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/metabolismo , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Metástase Linfática , Masculino , Camundongos , Camundongos Nus , Estadiamento de Neoplasias , Complexo Repressor Polycomb 2/genética , Fator de Transcrição 4/genética , Ensaios Antitumorais Modelo de Xenoenxerto , beta Catenina/genética
13.
Med Sci Monit ; 24: 2541-2549, 2018 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-29694335

RESUMO

BACKGROUND Histone H2A deubiquitinase MYSM1 has recently been shown to be essential for hematopoiesis and hematopoietic stem cell (HSC) function in both mice and humans. However, conventional MYSM1 knockouts cause partial embryonic lethality and growth retardation, and it is difficult to convincingly remove the effects of environmental factors on HSC differentiation and function. MATERIAL AND METHODS MYSM1 conditional knockout (cKO) mice were efficiently induced by using the Vav1-cre transgenic system. The Vav-Cre MYSM1 cKO mice were then analyzed to verify the intrinsic role of MYSM1 in hematopoietic cells. RESULTS MYSM1 cKO mice were viable and were born at normal litter sizes. At steady state, we observed a defect in hematopoiesis, including reduced bone marrow cellularity and abnormal HSC function. MYSM1 deletion drives HSCs from quiescence into rapid cycling, and MYSM1-deficient HSCs display impaired engraftment. In particular, the immature cycling cKO HSCs have elevated reactive oxygen species (ROS) levels and are prone to apoptosis, resulting in the exhaustion of the stem cell pool during stress response to 5-FU. CONCLUSIONS Our study using MYSM1 cKO mice confirms the important role of MYSM1 in maintaining HSC quiescence and survival.


Assuntos
Endopeptidases/metabolismo , Células-Tronco Hematopoéticas/metabolismo , Animais , Apoptose/fisiologia , Diferenciação Celular/fisiologia , Divisão Celular , Sobrevivência Celular/genética , Endopeptidases/genética , Hematopoese , Células-Tronco Hematopoéticas/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Espécies Reativas de Oxigênio/metabolismo , Transativadores , Proteases Específicas de Ubiquitina
14.
J Comput Chem ; 38(18): 1574-1582, 2017 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-28378338

RESUMO

In this work, we designed a series of superalkali-doped Si12 C12 nanocage M3 O@Si12 C12 (M = Li, Na, K) with donor-acceptor framework. Density functional theory calculations demonstrated that the HOMO-LUMO gap of the complexes conspicuously narrowed with increase of atomic number of the alkali metal, the value decreased from 5.452 eV of pure Si12 C12 nanocage to 3.750, 2.984, and 2.634 eV of Li3 O@Si12 C12 , Na3 O@Si12 C12 , and K3 O@Si12 C12 , respectively. This finding shows that the pristine Si12 C12 cluster could be transformed to n-type semiconductor by introduction of the superalkali M3 O. We also showed that the superalkali doping remarkably enhanced the first hyperpolarizability of Si12 C12 . Among the studied systems, K3 O@Si12 C12 not only has the narrowest gap but also has the strongest nonlinear optical (NLO) properties, its first hyperpolarizability reached as high as 21695 a.u. The striking results presented in this work will be beneficial for potential applications of the Si12 C12 -based nanostructure in the electronic nanodevices and high-performance NLO materials. © 2017 Wiley Periodicals, Inc.

15.
BMC Infect Dis ; 17(1): 310, 2017 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-28446129

RESUMO

BACKGROUND: Known predictors of neurosyphilis were mainly drawn from human immunodeficiency virus (HIV)-infected syphilis patients, which may not be applicable to HIV-negative populations as they have different characteristics, particularly those with neurological symptoms. This study aimed to identify novel predictors of HIV-negative symptomatic neurosyphilis (S-NS). METHODS: From June 2005 to June 2015, 370 HIV-negative syphilis patients with neurological symptoms were recruited, consisting of 191 S-NS patients (including 123 confirmed neurosyphilis and 68 probable neurosyphilis patients) and 179 syphilis/non-neurosyphilis (N-NS) patients. Clinical and laboratory characteristics of S-NS were compared with N-NS to identify factors predictive of S-NS. Serum rapid plasma reagin (RPR), Treponema pallidum particle agglutination (TPPA), and their parallel testing format for screening S-NS were evaluated. RESULTS: The likelihood of S-NS was positively associated with the serum RPR and TPPA titers. The serum TPPA titers performed better than the serum RPR titers in screening S-NS. The optimal cut-off points to recognize S-NS were serum RPR titer ≥1:4 and serum TPPA titer ≥1:2560 respectively. A parallel testing format of a serum RPR titer ≥1:2 and serum TPPA titer ≥1:1280 screened out 95.8% of S-NS and all confirmed cases of neurosyphilis. S-NS was independently associated with male sex, serum RPR titer ≥1:4, serum TPPA titer ≥1:2560, and elevated serum creatine kinase. Concurrence of these factors increased the likelihood of S-NS. CONCLUSIONS: Quantitation of serum TPPA is worthwhile and performs better than serum RPR in screening S-NS. Serum RPR, serum TPPA, male sex, and serum creatine kinase can predict S-NS. Moreover, patients with both a serum RPR titer <1:2 and a serum TPPA titer <1:1280 have a low probability of S-NS, suggesting that it is reasonable to reduce lumbar punctures in such individuals.


Assuntos
Neurossífilis/diagnóstico , Neurossífilis/etiologia , Testes de Aglutinação/métodos , Feminino , Soropositividade para HIV , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Punção Espinal , Sífilis/complicações , Sorodiagnóstico da Sífilis , Treponema pallidum/patogenicidade
16.
Cell Physiol Biochem ; 38(3): 1055-62, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26938051

RESUMO

BACKGROUND/AIMS: Angiotensin converting enzyme 2 (ACE2) treatment suppresses the severity of acute lung injury (ALI), through antagonizing hydrolyzing angiotensin II (AngII) and the ALI-induced apoptosis of pulmonary endothelial cells. Nevertheless, the effects of ACE2 on vessel permeability and its relationship with vascular endothelial growth factor a (VEGFa) remain ill-defined. In the current study, we examined the relationship between ACE2 and VEGFa in ALI model in mice. METHODS: Here, we used a previously published bleomycin method to induce ALI in mice, and treated the mice with ACE2. We analyzed the levels of VEGFa in these mice. The mouse lung vessel permeability was determined by a fluorescence pharmacokinetic assay following i.v. injection of 62.5µg/kg Visudyne. VEGFa pump or SU5416 pump was given to increase or decrease VEGFa effects, respectively. The long-term effects on lung function were determined by measurement of lung resistance using methacholine. RESULTS: ACE2 treatment did not alter VEGFa levels in lung, but antagonized the effects of VEGFa on increases of lung vessel permeability. Ectogenic VEGFa abolished the antagonizing effects of ACE2 on the vessel permeability against VEGFa. On the other hand, suppression of VEGF signaling mimicked the effects of ACE2 on the vessel permeability against VEGFa. The suppression of vessel permeability resulted in improvement of lung function after ALI. CONCLUSION: ACE2 may antagonize the VEGFa-mediated increases in lung vessel permeability during ALI, resulting in improvement of lung function after ALI.


Assuntos
Lesão Pulmonar Aguda/dietoterapia , Permeabilidade Capilar/efeitos dos fármacos , Peptidil Dipeptidase A/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/metabolismo , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/metabolismo , Enzima de Conversão de Angiotensina 2 , Animais , Bleomicina/efeitos adversos , Células Endoteliais , Regulação da Expressão Gênica , Indóis/administração & dosagem , Indóis/farmacologia , Camundongos , Peptidil Dipeptidase A/farmacologia , Porfirinas/administração & dosagem , Porfirinas/farmacocinética , Pirróis/administração & dosagem , Pirróis/farmacologia , Verteporfina
17.
Mol Cell Biochem ; 422(1-2): 97-107, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27629785

RESUMO

Lung cancer is the most frequent cancer in the world. Previous studies have shown that ubiquitin-specific protease 39 (USP39) is upregulated in several cancers and associated with tumor malignant characters. However, the effects of USP39 in lung cancer have not been well understood. In the present study, we found USP39 was generally expressed higher in human lung cancer tissues than in normal tissues by Oncomine database mining, qRT-PCR, and western blot assay. Knockdown of USP39 expression markedly reduced the proliferative and colony-forming ability of lung cancer cell lines 95D and A549. Flow cytometric analysis showed that USP39 knockdown induced cell cycle arrest at G2/M phase and enhanced cell apoptosis in 95D cells. Moreover, depletion of USP39 blocked activation of Akt, mTOR, p53, and PARP signaling pathways. Taken together, our study indicates that USP39 may be functionally involved in lung cancer growth and act as a potential molecular target for human lung cancer diagnosis and treatment.


Assuntos
Divisão Celular , Fase G2 , Regulação Enzimológica da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/enzimologia , Proteínas de Neoplasias/biossíntese , Transdução de Sinais , Proteases Específicas de Ubiquitina/biossíntese , Linhagem Celular Tumoral , Feminino , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patologia , Masculino , Proteínas de Neoplasias/genética , Proteases Específicas de Ubiquitina/genética
18.
Nucleic Acids Res ; 41(Database issue): D553-60, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23197658

RESUMO

Disease and Gene Annotations database (DGA, http://dga.nubic.northwestern.edu) is a collaborative effort aiming to provide a comprehensive and integrative annotation of the human genes in disease network context by integrating computable controlled vocabulary of the Disease Ontology (DO version 3 revision 2510, which has 8043 inherited, developmental and acquired human diseases), NCBI Gene Reference Into Function (GeneRIF) and molecular interaction network (MIN). DGA integrates these resources together using semantic mappings to build an integrative set of disease-to-gene and gene-to-gene relationships with excellent coverage based on current knowledge. DGA is kept current by periodically reparsing DO, GeneRIF, and MINs. DGA provides a user-friendly and interactive web interface system enabling users to efficiently query, download and visualize the DO tree structure and annotations as a tree, a network graph or a tabular list. To facilitate integrative analysis, DGA provides a web service Application Programming Interface for integration with external analytic tools.


Assuntos
Bases de Dados Genéticas , Doença/genética , Genes , Anotação de Sequência Molecular , Humanos , Internet , Proteínas/genética , Proteínas/metabolismo , Vocabulário Controlado
19.
Langmuir ; 30(50): 15229-37, 2014 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-25489918

RESUMO

Although the hydrogel network has been widely investigated as a carrier for enzyme immobilization, to in situ encapsulate enzymes into a hydrogel network in an efficient, practical, and active way is still one of the great challenges in the field of biochemical engineering. Here, we report a new protocol to address this issue by encapsulating enzyme into poly(ethylene glycol) (PEG) hydrogel network grafted on polymeric substrates. In our strategy, isopropyl thioxanthone semipinacol (ITXSP) dormant groups were first planted onto the surface of a plastic matrix with low density polyethylene (LDPE) film as a model by a UV-induced abstracting hydrogen-coupling reaction. As a proof of concept, lipase, which could catalyze esterification of glucose with palmitic acid, then was in situ net-immobilized into a PEG-based hydrogel network layer through a visible light-induced surface controlled/living graft cross-linking polymerization. This strategy demonstrates the following novel significant merits: (1) in comparison with the UV irradiation or high temperature, the visible light and room temperature used provide a friendly condition to maintain activity of enzyme during immobilization; (2) the uniqueness of controlled/living cross-linking polymerization not only makes it easy to form a uniform PEG hydrogel network, which is a benefit to avoid the leakage of net-immobilizing enzyme, but also to tune the net-thickness or capacity to accommodate enzyme; and (3) as compared to systems of nanoparticles and porous matrixes, the flexible/robust end-products of the surface net-immobilizing enzyme with polymer film are more suitable to be applied in a bioreactor due to their features of easier separation and reuse. We confirmed that this catalytic film could retain almost all of its initial activity after seven batches of 24 h esterifications. The proposed strategy provides an extremely simple, effective, and flexible method for enzyme immobilization.


Assuntos
Enzimas Imobilizadas/química , Hidrogéis/química , Polietilenoglicóis/química , Animais , Biocatálise , Cápsulas , Enzimas Imobilizadas/metabolismo , Luz , Lipase/química , Processos Fotoquímicos , Polietileno/química , Polimerização , Solventes/química , Propriedades de Superfície , Suínos , Xantonas/química
20.
PeerJ ; 12: e17128, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38562994

RESUMO

Background: Interaction identification is important in epidemiological studies and can be detected by including a product term in the model. However, as Rothman noted, a product term in exponential models may be regarded as multiplicative rather than additive to better reflect biological interactions. Currently, the additive interaction is largely measured by the relative excess risk due to interaction (RERI), the attributable proportion due to interaction (AP), and the synergy index (S), and confidence intervals are developed via frequentist approaches. However, few studies have focused on the same issue from a Bayesian perspective. The present study aims to provide a Bayesian view of the estimation and credible intervals of the additive interaction measures. Methods: Bayesian logistic regression was employed, and estimates and credible intervals were calculated from posterior samples of the RERI, AP and S. Since Bayesian inference depends only on posterior samples, it is very easy to apply this method to preventive factors. The validity of the proposed method was verified by comparing the Bayesian method with the delta and bootstrap approaches in simulation studies with example data. Results: In all the simulation studies, the Bayesian estimates were very close to the corresponding true values. Due to the skewness of the interaction measures, compared with the confidence intervals of the delta method, the credible intervals of the Bayesian approach were more balanced and matched the nominal 95% level. Compared with the bootstrap method, the Bayesian method appeared to be a competitive alternative and fared better when small sample sizes were used. Conclusions: The proposed Bayesian method is a competitive alternative to other methods. This approach can assist epidemiologists in detecting additive-scale interactions.


Assuntos
Teorema de Bayes , Simulação por Computador , Modelos Logísticos , Estudos Epidemiológicos , Tamanho da Amostra
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