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1.
J Biomed Inform ; 149: 104571, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38092247

RESUMEN

Epidemiological models allow for quantifying the dynamic characteristics of large-scale outbreaks. However, capturing detailed and accurate epidemiological information often requires consideration of multiple kinetic mechanisms and parameters. Due to the uncertainty of pandemic evolution, such as pathogen variation, host immune response and changes in mitigation strategies, the parameter evaluation and state prediction of complex epidemiological models are challenging. Here, we develop a data-driven epidemic model with a generalized SEIR mechanistic structure that includes new compartments, human mobility and vaccination protection. To address the issue of model complexity, we embed the epidemiological model dynamics into physics-informed neural networks (PINN), taking the observed series of time instances as direct input of the network to simultaneously infer unknown parameters and unobserved dynamics of the underlying model. Using actual data during the COVID-19 outbreak in Australia, Israel, and Switzerland, our model framework demonstrates satisfactory performance in multi-step ahead predictions compared to several benchmark models. Moreover, our model infers time-varying parameters such as transmission rates, hospitalization ratios, and effective reproduction numbers, as well as calculates the latent period and asymptomatic infection count, which are typically unreported in public data. Finally, we employ the proposed data-driven model to analyze the impact of different mitigation strategies on COVID-19.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , COVID-19/prevención & control , Pandemias/prevención & control , Brotes de Enfermedades/prevención & control , Incertidumbre , Vacunación
2.
Zhonghua Bing Li Xue Za Zhi ; 43(4): 236-40, 2014 Apr.
Artículo en Zh | MEDLINE | ID: mdl-24915813

RESUMEN

OBJECTIVE: To explore the expression of breast cancer resistance protein (ABCG2), p-glycoprotein (P-gp) in residual breast cancer tissue after chemotherapy and their correlation with epithelial mesenchymal transition (EMT). METHODS: Seventy-six cases of breast cancer were collected. The expression of ABCG2, P-gp and EMT markers E-cadherin and vimentin in residual breast cancer tissue after chemotherapy was detected by immunohistochemistry (EnVision method). MCF7 cells were divided into three group:untreated control group, positive control (TGF-ß1 induced) group and drug surviving cells (DSC) group (selected viable MCF7 cells after docetaxel and epirubicin treatment). The expression of EMT markers E-cadherin and vimentin was detected by immunofluorescence. The mRNA and protein expression of ABCG2, P-gp and EMT markers were detected by reverse transcription-polymerase chain reaction (RT-PCR) and Western blot, respectively. RESULTS: Compared with breast cancer tissue before chemotherapy, ABCG2, P-gp and vimentin protein were highly expressed in residual breast cancer tissue after chemotherapy. The expression of ABCG2 and P-gp correlated positively with vimentin protein (r1=0.97, P1=0.000; r2=0.83, P2=0.001) and negatively with E-cadherin protein (r3=-0.55, P3=0.010; r4=-0.43, P4=0.020) expression. RT-PCR results showed that ABCG2, P-gp and vimentin mRNA were highly expressed in residual breast cancer tissue after chemotherapy. The expression of ABCG2 and P-gp mRNA correlated positively with vimentin mRNA (r1=0.99, r2=0.96, P<0.05) but negatively with E-cadherin protein (r3=-0.99, r4=-0.98, P<0.05); Western blot showed that ABCG2, P-gp and vimentin protein were highly expressed in residual breast cancer tissue after chemotherapy. The expression of ABCG2 and P-gp protein correlated positively with vimentin protein (r1=0.98, r2=0.89, P<0.05) and negatively with E-cadherin protein (r3=-0.47, r4=-0.33, P<0.05). CONCLUSIONS: The expression of resistance-associated proteins in the residual breast cancer tissue after chemotherapy is significantly correlated with EMT. The expression of EMT profile may be one of important mechanisms for multidrug resistance in breast cancer.


Asunto(s)
Transportadoras de Casetes de Unión a ATP/metabolismo , Neoplasias de la Mama/metabolismo , Transición Epitelial-Mesenquimal , Proteínas de Neoplasias/metabolismo , Neoplasia Residual/metabolismo , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Transportadoras de Casetes de Unión a ATP/genética , Adulto , Anciano , Antibióticos Antineoplásicos/farmacología , Antígenos CD , Antineoplásicos/farmacología , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasias de la Mama/patología , Neoplasias de la Mama/terapia , Cadherinas/genética , Cadherinas/metabolismo , Ciclofosfamida/uso terapéutico , Docetaxel , Doxorrubicina/uso terapéutico , Epirrubicina/farmacología , Femenino , Humanos , Células MCF-7 , Persona de Mediana Edad , Proteínas de Neoplasias/genética , ARN Mensajero/metabolismo , Taxoides/farmacología , Taxoides/uso terapéutico , Vimentina/genética , Vimentina/metabolismo
3.
Zhonghua Yi Xue Za Zhi ; 93(15): 1182-7, 2013 Apr 16.
Artículo en Zh | MEDLINE | ID: mdl-23902893

RESUMEN

OBJECTIVE: To explore the effects of silencing hypoxia inducible factor-2α (HIF-2α) by small interference RNA on the growth of mammosphere cells in nude mice under hypoxic microenvironment. METHODS: The empty and interference vectors were transfected into MCF-7 cell. Then G418 was added to screen the positive cells to obtain stable cell line. The empty and interference vectors were inoculated subcutaneously into left and right back near hind limb of nude mice. The volume and weight of tumors were calculated respectively. The expressions of HIF-2α, CD44, OCT-4 and KLF-4 protein in xenograft tumor tissues were detected by Western blot. RESULTS: The expression vector of HIF-2α-siRNA was successfully established. The formation of mammosphere was lowered by silencing HIF-2α gene expression. In contract to empty vector group cell, there were obvious decreases in the volumes and weights of tumors in interference group (P < 0.05). The expression of HIF-2α protein of interference group (0.42 ± 0.01) was much lower than that of the empty vector group (0.89 ± 0.03, P < 0.05), the expression of CD44 protein of interference group (0.21 ± 0.01) was much lower than the empty vector group (0.78 ± 0.03, P < 0.05), the expression of OCT-4 protein of interference group (0.42 ± 0.01)was much lower than the empty vector group (0.68 ± 0.03, P < 0.05) and the expression of KLF-4 protein of interference group (0.34 ± 0.01) was much lower than the empty vector group (0.72 ± 0.03, P < 0.05). CONCLUSION: Silencing HIF-2α gene can effectively inhibit the growth of breast cancer stem cells in nude mice under hypoxic microenvironment. Its mechanism may be through inhibited capacity for self-renewal and proliferation of breast cancer stem cells in vivo through the down-regulated expressions of markers associated with stem cells. HIF-2α is expected to become a new target for gene therapy of breast cancer.


Asunto(s)
Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Hipoxia , Interferencia de ARN , ARN Interferente Pequeño/genética , Microambiente Tumoral , Animales , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Proliferación Celular , Femenino , Vectores Genéticos , Humanos , Receptores de Hialuranos/metabolismo , Factor 4 Similar a Kruppel , Factores de Transcripción de Tipo Kruppel/metabolismo , Células MCF-7 , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Transfección , Ensayos Antitumor por Modelo de Xenoinjerto
4.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 35(2): 171-6, 2013 Apr.
Artículo en Zh | MEDLINE | ID: mdl-23643006

RESUMEN

OBJECTIVE: To compare the expression differences of breast cancer resistance protein(BCRP/ABCG2) and P-glycoprotein(P-gp) in breast cancer tissue before chemotherapy and in residual breast cancer tissue, and to explore its correlation with breast cancer stem cells. METHODS: Immunohistochemistry was used to detect the expression of ABCG2, P-gp, and breast cancer stem cells(BCSCs) markers(CD44 and CD24) in breast cancer tissue before chemotherapy and residual breast cancer tissue after chemotherapy. Immunofluorescence was applied for determination of the CD44 and CD24 protein expressions of BCSCs microspheres cells. The monoclone-forming ability of BCSCs microspheres cells was detected by limited dilution assay. The expressions of ABCG2, P-gp, CD44, and CD24 proteins were detected by Western blot. RESULTS: Compared with those in breast cancer tissue before chemotherapy, the expression levels of ABCG2 and P-gp were positively correlated with the expression level of CD44 protein(Χ(2)=41.34, r=0.83;Χ(2)=22.81, r=0.61) in residual breast cancer tissue after chemotherapy;meanwhile, they were negatively correlated with the expression of CD24 protein(Χ(2)=-21.25, r=0.72;Χ(2)=-17.26, r=0.65) (all P<0.05) .The diameter of BCSCs microspheres were increased significantly after chemotherapy.The content of BCSCs increased by about 2.5 times after chemotherapy.The expressions of ABCG2, P-gp and CD44 proteins significantly increased and that of CD24 protein significantly declined(P<0.05) . CONCLUSION: Chemotherapy endows residual breast cancer tissue with cancer stem cells-like features, leading to multidrug resistance of breast cancer.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Transportadoras de Casetes de Unión a ATP/metabolismo , Neoplasias de la Mama/metabolismo , Proteínas de Neoplasias/metabolismo , Células Madre Neoplásicas/citología , Subfamilia B de Transportador de Casetes de Unión a ATP , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Adulto , Anciano , Neoplasias de la Mama/tratamiento farmacológico , Antígeno CD24/metabolismo , Técnicas de Cultivo de Célula , Resistencia a Antineoplásicos , Femenino , Humanos , Receptores de Hialuranos/metabolismo , Persona de Mediana Edad , Neoplasia Residual , Células Madre Neoplásicas/metabolismo
5.
Mol Immunol ; 157: 186-194, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37054520

RESUMEN

Systemic lupus erythematosus (SLE) is a systemic autoimmune disease. This study aimed to investigate the role of SMAD specific E3 ubiquitin protein ligase 1 (SMURF1) in the Th17 and Th17.1 differentiation and Treg/Th17 imbalance, which are major factors contributing to the pathogenesis of SLE. SLE patients and healthy individuals were recruited to detect the SMURF1 levels in naïve CD4+ cells from peripheral blood. Purified and expanded naïve CD4+ T cells were employed to evaluate the effects of SMURF1 on Th17 and Th17.1 polarization in vitro. MRL/lpr lupus model was employed to explore the disease phenotype as well as Treg/Th17 balance in vivo. The results showed that SMURF1 was down-regulated in naïve CD4+ T cells in peripheral blood of patients with SLE and in spleen of MRL/lpr mice. SMURF1 overexpression suppressed the polarization of naïve CD4+ T cells toward Th17 and Th17.1 phenotype and down-regulated the expression of retinoid-related orphan receptor-gammat (RORγt). Subsequently, SMURF1 down-regulation aggravated the disease phenotype, inflammation, and the Treg/Th17 imbalance in MRL/lpr mice. Furthermore, we found that SMURF overexpression promoted the ubiquitination and decreases the stability of RORγt. In conclusion, SMURF1 inhibited the polarization of Th17 and Th17.1 cells and improved the Treg/Th17 imbalance in SLE, which was mediated as least partly by the ubiquitination of RORγt.


Asunto(s)
Lupus Eritematoso Sistémico , Linfocitos T Reguladores , Animales , Humanos , Ratones , Ratones Endogámicos MRL lpr , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/metabolismo , Células Th17 , Ubiquitinación
6.
Emerg Microbes Infect ; 12(1): 2149935, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36398721

RESUMEN

It is critical to determine the real-world performance of vaccines against coronavirus disease 2019 (COVID-19) so that appropriate treatments and policies can be implemented. There was a rapid wave of infections by the Omicron variant in Jilin Province (China) during spring 2022. We examined the effectiveness of inactivated vaccines against Omicron using real-world data from this epidemic. This retrospective case-case study of vaccine effectiveness (VE) examined infected patients who were quarantined and treated from April 16 to June 8, 2022 and responded to an electronic questionnaire. Data were analyzed by univariable and multivariable analyses. A total of 2968 cases with SARS-CoV-2 infections (asymptomatic: 1061, mild disease: 1763, pneumonia: 126, severe disease: 18) were enrolled in the study. Multivariable regression indicated that the risk for pneumonia or severe disease was greater in those who were older or had underlying diseases, but was less in those who received COVID-19 vaccines. Relative to no vaccination, VE against the composite of pneumonia and severe disease was significant for those who received 2 doses (60.1%, 95%CI: 40.0%, 73.5%) or 3 doses (68.1%, 95%CI: 44.6%, 81.7%), and VE was similar in the subgroups of males and females. However, VE against the composite of all three classes of symptomatic diseases was not significant overall, nor after stratification by sex. There was no statistical difference in the VE of vaccines from different manufacturers. The inactivated COVID-19 vaccines protected patients against pneumonia and severe disease from Omicron infection, and booster vaccination enhanced this effect.


Asunto(s)
COVID-19 , Neumonía , Femenino , Masculino , Humanos , Vacunas contra la COVID-19 , SARS-CoV-2 , COVID-19/prevención & control , Estudios Retrospectivos , China/epidemiología
7.
8.
Am J Cancer Res ; 11(5): 1962-1981, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34094664

RESUMEN

Trastuzumab has been widely used for treatment of HER-2-positive breast cancer patients, however, the clinical response has been restricted due to emergence of resistance. Recent studies indicate that long noncoding RNA AGAP2-AS1 (lncRNA AGAP2-AS1) plays an important role in cancer resistance. However, the precise regulatory function and therapeutic potential of AGAP2-AS1 in trastuzumab resistance is still not defined. In this study, we sought to reveal the essential role of AGAP2-AS1 in trastuzumab resistance. Our results suggest that AGAP2-AS1 disseminates trastuzumab resistance via packaging into exosomes. Exosomal AGAP2-AS1 induces trastuzumab resistance via modulating ATG10 expression and autophagy activity. Mechanically, AGAP2-AS1 is associated with ELAVL1 protein, and the AGAP2-AS1-ELAVL1 complex could directly bind to the promoter region of ATG10, inducing H3K27ac and H3K4me3 enrichment, which finally activates ATG10 transcription. AGAP2-AS1-targeting antisense oligonucleotides (ASO) substantially increased trastuzumab-induced cytotoxicity. Clinically, increased expression of serum exosomal AGAP2-AS1 was associate with poor response to trastuzumab treatment. In conclusion, exosomal AGAP2-AS1 increased trastuzumab resistance via promoting ATG10 expression and inducing autophagy. Therefore, AGAP2-AS1 may serve as predictive biomarker and therapeutic target for HER-2+ breast cancer patients.

9.
Oncogene ; 40(4): 833-847, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33273726

RESUMEN

Trastuzumab resistance has been becoming a major obstacle for treatment of HER-2-positive breast cancer patients. Increasing evidence suggests that mesenchymal stem cells (MSCs) play critical roles during the formation of drug resistance, however, the underlying mechanism is not well known. In this study, mass spectrometry, RNA pulldown and RNA immunoprecipitation assays were performed to verify the direct interactions among AGAP2-AS1 and other associated targets, such as human antigen R (HuR), miR-15a-5p, and carnitine palmitoyl transferase 1 (CPT1). In vitro and in vivo experimental assays were done to clarify the functional role of AGAP2-AS1 in trastuzumab resistance, stemness, and fatty acid oxidation (FAO). The results showed that MSC co-culture induced trastuzumab resistance. AGAP2-AS1 was upregulated in MSC-cultured cells, and knockdown of AGAP2-AS1 reversed the MSC-mediated trastuzumab resistance. Furthermore, MSC culture-induced AGAP2-AS1 regulates stemness and trastuzumab resistance via activating FAO. Mechanistically, AGAP2-AS1 is associated with HuR, and the AGAP2-AS1-HuR complex could directly bind to the CPT1, increasing its expression via improving RNA stability. In addition, AGAP2-AS1 could serve as ceRNA via sponging miR-15a-5p and releasing CPT1 mRNA. Clinically, increased expression of serum AGAP2-AS1 predicts poor response to trastuzumab treatment in breast cancer patients. In conclusion, MSC culture-induced AGAP2-AS1 caused stemness and trastuzumab resistance via promoting CPT1 expression and inducing FAO. Our results provide new insight of the role of MSCs in trastuzumab resistance and AGAP2-AS1 could be promising predictive biomarker and therapeutic target for HER-2+ breast cancer patients.


Asunto(s)
Neoplasias de la Mama/tratamiento farmacológico , Carnitina O-Palmitoiltransferasa/genética , Ácidos Grasos/metabolismo , Células Madre Mesenquimatosas/fisiología , ARN Largo no Codificante/fisiología , Trastuzumab/uso terapéutico , Neoplasias de la Mama/metabolismo , Carnitina O-Palmitoiltransferasa/fisiología , Línea Celular Tumoral , Resistencia a Antineoplásicos , Proteína 1 Similar a ELAV/fisiología , Femenino , Humanos , MicroARNs/fisiología , Oxidación-Reducción
10.
Can J Ophthalmol ; 56(5): 299-306, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-33485841

RESUMEN

OBJECTIVE: To analyze the rates of blindness with the demographics and clinical characteristics of patients with primary angle-closure disease (PACD) to provide a comprehensive epidemiologic reference in China. METHODS: A retrospective analysis was conducted in the Chinese Glaucoma Study Consortium database, which is a national multicenter glaucoma research alliance of 111 hospitals participating between December 21, 2015 and September 9, 2018. The diagnosis of PACD was made by qualified physicians through examination. Comparison of sex, age, family history, subtypes of PACD, and blindness were analyzed. RESULTS: A total of 5762 glaucoma patients were included, of which 4588 (79.6%) had PACD. Of PACD patients, 72.1% were female with the sex ratio (F/M) of 2.6, and the average age of patients was 63.8±9.3 years with the majority between 60 and 70 years. Additionally, 30% of these patients had low vision in one eye, 8.8% had low vision in both eyes, 1.7% had blindness in one eye, and 0.3% had blindness in both eyes. There were statistical differences with regards to age between male and female patients with PACD, with male patients being older on average. Primary angle-closure glaucoma was more commonly diagnosed in males (60%) compared to females (35.9%), whereas acute primary angle closure (APAC) was more commonly diagnosed in females (54.3%) compared to males (37.7%). The visual acuity in APAC patients was lower and the rate of low vision and blindness was higher than other subtypes. CONCLUSION: PACD was the major type of glaucoma in Chinese hospitals. There were more female patients with PACD, mostly between 60 and 70 years old, with higher rates of APAC in women. APAC resulted in the worst visual outcomes of all PACD subtypes.


Asunto(s)
Glaucoma de Ángulo Cerrado , Baja Visión , Anciano , Ceguera/diagnóstico , Ceguera/epidemiología , Ceguera/etiología , China/epidemiología , Femenino , Glaucoma de Ángulo Cerrado/diagnóstico , Glaucoma de Ángulo Cerrado/epidemiología , Humanos , Presión Intraocular , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Baja Visión/diagnóstico , Baja Visión/epidemiología
11.
Front Oncol ; 10: 533176, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33072568

RESUMEN

The clinical significance and the function of chaperonin-containing TCP1 complex 3 (CCT-3) in breast cancer remain unknown. In this study, we found that CCT-3 was markedly overexpressed in breast cancer tissues. Statistical analysis revealed a significant correlation of CCT-3 expression with advanced breast cancer clinical stage and poorer survival. Ablation of CCT-3 knocked down the proliferation and the tumorigenicity of breast cancer cells in vitro and in vivo. CCT-3 may regulate breast cancer cell proliferation through a ceRNA network between miR-223 and ß-catenin, thus affecting Wnt/ß-catenin signaling pathway activation. We also validated that CCT-3 and ß-catenin are novel direct targets of tumor suppressor miR-223. Our results suggest that both mRNA and the protein levels of CCT-3 are potential diagnosis biomarkers and therapeutic targets for breast cancer.

13.
PLoS One ; 7(6): e39520, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22761812

RESUMEN

BACKGROUND: Accumulating evidence suggested that epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) characteristics, both of which contribute to tumor invasion and metastasis, are interrelated with miR-21. MiR-21 is one of the important microRNAs associated with tumor progression and metastasis, but the molecular mechanisms underlying EMT and CSC phenotype during miR-21 contributes to migration and invasion of breast cancer cells remain to be elucidated. METHODOLOGY/PRINCIPAL FINDINGS: In this study, MDA-MB-231/anti-miR-21 cells were established by transfected hsa-miR-21 antagomir into breast cancer MDA-MB-231 cells. EMT was evaluated by the changes of mesenchymal cell markers (N-cadherin, Vimentin, and alpha-SMA), epithelial cell marker (E-cadherin), as well as capacities of cell migration and invasion; CSC phenotype was measured using the changes of CSC surface markers (ALDH1 and CD44), and the capacity of sphereforming (mammospheres). We found that antagonism of miR-21 reversed EMT and CSC phenotype, accompanied with PTEN up-regulation and AKT/ERK1/2 inactivation. Interestingly, down-regulation of PTEN by siPTEN suppressed the effects of miR-21 antagomir on EMT and CSC phenotype, confirming that PTEN is a target of miR-21 in reversing EMT and CSC phenotype. The inhibitors of PI3K-AKT and ERK1/2 pathways, LY294002 and U0126, both significantly suppressed EMT and CSC phenotype, indicating that AKT and ERK1/2 pathways are required for miR-21 mediating EMT and CSC phenotype. CONCLUSIONS/SIGNIFICANCE: In conclusion, our results demonstrated that antagonism of miR-21 reverses EMT and CSC phenotype through targeting PTEN, via inactivation of AKT and ERK1/2 pathways, and showed a novel mechanism of which might relieve the malignant biological behaviors of breast cancer.


Asunto(s)
Transición Epitelial-Mesenquimal/genética , Sistema de Señalización de MAP Quinasas/fisiología , MicroARNs/genética , Células Madre Neoplásicas/metabolismo , Fosfohidrolasa PTEN/metabolismo , Proteínas Proto-Oncogénicas c-akt/metabolismo , Actinas/genética , Actinas/metabolismo , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Cadherinas/genética , Cadherinas/metabolismo , Línea Celular Tumoral , Movimiento Celular/genética , Femenino , Humanos , MicroARNs/metabolismo , Fosfohidrolasa PTEN/genética , Fenotipo , Proteínas Proto-Oncogénicas c-akt/genética , Vimentina/genética , Vimentina/metabolismo
14.
J Chem Phys ; 122(15): 151103, 2005 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-15945617

RESUMEN

The Coulomb explosion of ammonia clusters induced by nanosecond laser field with intensity in the range of 10(10)-10(12) W cm(-2) and wavelength of 532 and 1064 nm has been studied. N2+ and N3+ ions are the main multicharged ions at 532 nm, while He-like N5+ ion is the domain multicharged ion at 1064 nm.

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