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1.
Anal Bioanal Chem ; 416(1): 203-214, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37914955

RESUMEN

In this study, an integrated QuEChERS method was developed for the rapid determination of 22 per- and polyfluoroalkyl substances (PFASs) in milk by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The extraction and purification processes were combined into one step with this method. Meanwhile, the solid-liquid separation was carried out by magnetic suction (Fe3O4-SiO2) instead of the centrifugal process. The primary experimental parameters were optimized, including the type of extraction solvent, the amounts of magnetic nanomaterials (Fe3O4-SiO2), and the purification materials (ZrO2 and C18). The developed method exhibits high precision (RSDs < 9.9%), low limits of detection (0.004-0.079 µg/kg) and limits of quantitation (0.01-0.26 µg/kg), and acceptable recovery (71.7-116%) under optimized conditions. The developed integrated QuEChERS method had clear superiority in terms of sample pretreatment time, operating procedures, reagent amount, and recovery. This makes it an excellent alternative analytical technique for PFAS residue measurement at low micrograms-per-kilogram ranges with desirable sensitivity.


Asunto(s)
Fluorocarburos , Espectrometría de Masas en Tándem , Animales , Cromatografía Liquida , Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Extracción en Fase Sólida/métodos , Leche/química , Dióxido de Silicio , Cromatografía Líquida con Espectrometría de Masas , Fluorocarburos/análisis
2.
Cancer Immunol Immunother ; 72(4): 985-1001, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36251028

RESUMEN

About 85% of patients with colorectal cancer (CRC) have the non-microsatellite instability-high (non-MSI-H) subtype, and many cannot benefit from immune checkpoint blockade. A potential reason for this is that most non-MSI-H colorectal cancers are immunologically "cold" due to poor CD8+ T cell infiltration. In the present study, we screened for potential cancer-testis antigens (CTAs) by comparing the bioinformatics of CD8+ T effector memory (Tem) cell infiltration between MSI-H and non-MSI-H CRC. Two ODF2-derived epitope peptides, P433 and P609, displayed immunogenicity and increased the proportion of CD8+ T effector memory (Tem) cells in vitro and in vivo. The adoptive transfer of peptide pool-induced CTLs inhibited tumor growth and enhanced CD8+ T cell infiltration in tumor-bearing NOD/SCID mice. The mechanistic study showed that knockdown of ODF2 in CRC cells promoted interleukin-15 expression, which facilitated CD8+ T cell proliferation. In conclusion, ODF2, a CTA, was negatively correlated with CD8+ T cell infiltration in "cold" non-MSI-H CRC and was selected based on the results of bioinformatics analyses. The corresponding HLA-A2 restricted epitope peptide induced antigen-specific CTLs. Immunotherapy targeting ODF2 could improve CTA infiltration via upregulating IL-15 in non-MSI-H CRC. This tumor antigen screening strategy could be exploited to develop therapeutic vaccines targeting non-MSI-H CRC.


Asunto(s)
Neoplasias Colorrectales , Linfocitos T Citotóxicos , Animales , Masculino , Ratones , Neoplasias Colorrectales/patología , Epítopos , Proteínas de Choque Térmico , Interleucina-15 , Ratones Endogámicos NOD , Ratones SCID , Péptidos , Testículo/patología , Vacunas de Subunidad , Vacunas contra el Cáncer
3.
Nanotechnology ; 31(17): 174002, 2020 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-31842002

RESUMEN

Interfacial heterostructuring has appeared to be an efficient strategy to address the efficiency and applicability of the photocatalysts in solar energy conversion. Herein, we developed one-dimensional (1D) α-Fe2O3/TiO2 nanoheterojunction arrays for enhanced photoelectrochemical (PEC) activity. α-Fe2O3 nanotubes were firstly prepared via anodization under controlled hydrodynamic conditions to increase the efficiency. 1D α-Fe2O3/TiO2 nanoheterojunction arrays were then prepared through a hydrothermal treatment and a subsequent annealing process. A controlled anodization by modulating the hydrodynamic conditions, added a fine coating of TiO2 overlayer, to finally give an optimized composition and geometry for improved light absorption and spatial charge separation efficiency. Consequently, the optimized α-Fe2O3 generated a photocurrent of 0.07 mA cm-2 (3.5 times higher than that of pristine α-Fe2O3), and the as-obtained α-Fe2O3/TiO2 nanoheterojunction exhibited a photocurrent intensity of 0.12 mA cm-2 (about 6 times higher than that of pristine α-Fe2O3). A long-term stability can also be ensured. The well-controlled architectures provides a guideline for synthesis of advanced nanomaterials.

4.
Bioorg Chem ; 98: 103644, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32033791

RESUMEN

Four new thymol derivatives (1-4), one new isothymol derivative (5), together with one known analogue (6) were isolated from the overground parts of Eupatorium fortunei. The structures were elucidated by extensive spectroscopic data analysis, including UV, IR, HR-ESIMS, 1D-, and 2D-NMR data. All compounds were evaluated for their cytotoxic effects against four human cancer cell lines using MTT assay. Compounds 1, 2, and 6 showed cytotoxicities with IC50 values 6.24-11.96 µM against MCF-7, HeLa, A549, and Hep G-2 cell lines.


Asunto(s)
Antineoplásicos Fitogénicos/farmacología , Eupatorium/química , Timol/farmacología , Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Estructura Molecular , Relación Estructura-Actividad , Timol/análogos & derivados , Timol/química
5.
Tumour Biol ; 37(1): 413-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26219900

RESUMEN

Papillary thyroid carcinoma is one of the most common subtypes of thyroid cancer and portends a good prognosis. N-cadherin (neural cadherin) is a member of the classical cadherin family and is often overexpressed in many types of cancers. Snail, a kind of zinc finger protein, is a transcriptional repressor which has been intensively studied in mammals. We investigate the immunohistochemical expression of Snail and N-cadherin in papillary thyroid carcinoma tissues and cells and then discuss the clinical value of Snail and N-cadherin expression. Immunohistochemical technique was performed to detect Snail and N-cadherin in 60 cases of papillary thyroid carcinoma and analyzed the relationship between the expression of Snail, N-cadherin, and clinicopathological indicators. Western blot was used to investigate the constitutive and inducible expression of Snail and N-cadherin. In our study, the expression rate of Snail and N-cadherin was 85.0 % (51/60) and 78.3 % (47/60), respectively, in papillary thyroid carcinoma. The expression rate of Snail and N-cadherin in thyroid papillary carcinoma with metastatic lymph nodes was 93.3 and 86.7 %, respectively, while in papillary thyroid carcinoma tissue without lymph node metastasis, the expression rate was 60.0 and 53.3 %, respectively. The positive correlation of Snail and N-cadherin was observed (r = 0.721, p < 0.01). In addition, Western blot further identified the constitutive and inducible expression of Snail and N-cadherin in papillary thyroid carcinoma tissues and cell lines. In conclusion, Snail and N-cadherin are constitutively and inducibly expressed in papillary thyroid carcinoma and may play important roles in the development and metastasis of papillary thyroid carcinoma. Snail and N-cadherin may be used as an effective indicator.


Asunto(s)
Antígenos CD/metabolismo , Cadherinas/metabolismo , Carcinoma/metabolismo , Regulación Neoplásica de la Expresión Génica , Factores de Transcripción de la Familia Snail/metabolismo , Neoplasias de la Tiroides/metabolismo , Adolescente , Adulto , Anciano , Biomarcadores de Tumor/metabolismo , Carcinoma Papilar , Línea Celular Tumoral , Femenino , Humanos , Inmunohistoquímica , Metástasis Linfática , Masculino , Persona de Mediana Edad , Cáncer Papilar Tiroideo , Adulto Joven
6.
Tumour Biol ; 36(4): 2773-8, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25448881

RESUMEN

Although deregulation of bone morphogenetic protein 2 (BMP2) signaling has been linked to various types of cancers, the relationships between abnormal activation of these signaling pathways and tumorigenesis are not clear in gastric cancer. We hypothesized that BMP2 might be involved in epithelial-mesenchymal transition (EMT) process of gastric cancer. Here, BMPR-II activation and inhibition in gastric cancer cell line AGS were induced with exogenous BMP2 and with BMPR-II small interfering RNA (siRNA), respectively. BMPR-II downstream signal molecules AKT, ERK phosphorylation, and EMT biomarkers (vimentin, snail, N-cadherin, and E-cadherin) were tested using the Western blot. In the present study, our results showed that BMP2 can induce AKT and ERK phosphorylation in a dose-dependent method, and endogenous BMPR-II can be inhibited completely by BMPR-II siRNA in AGS. Notably BMP2 alone treatment can induce the up-regulation of vimentin, snail, and N-cadherin in AGS cells, besides, the down-regulation of E-cadherin also occurred. On the contrary, BMPR-II siRNA significantly prohibited BMP2-induced AKT and ERK phosphorylation, at the same time, EMT biomarkers changes were not observed. On the other hand, BMPR-II knockdown could significantly affect AGS wound closure and the migration ability (p < 0.001) compared to control siRNA and BMP2 alone. In conclusion, this study suggested that EMT process can be triggered by the BMP2/BMPR axis in gastric cancer and then involved in the tumor cell migration, invasion, and metastasis via the activation of PI3K/AKT and MEK/ERK pathways. Our study lays a new foundation for the treatment of gastric cancer through antagonizing BMP2 system.


Asunto(s)
Proteína Morfogenética Ósea 2/genética , Transición Epitelial-Mesenquimal , Proteínas Proto-Oncogénicas c-akt/genética , Neoplasias Gástricas/genética , Proteína Morfogenética Ósea 2/metabolismo , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica , Humanos , Sistema de Señalización de MAP Quinasas/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Transducción de Señal/genética , Neoplasias Gástricas/patología
7.
Clin Exp Rheumatol ; 33(1): 69-76, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25327393

RESUMEN

OBJECTIVES: Statin is the most widely used as HMG-CoA reductase inhibitor, and contributes to clinically significant vascular risk reduction. However, the role of statins in the rheumatoid arthritis (RA) immunomodulation is debatable. This meta-analysis aimed to determine the efficacy of statins therapy in RA patients. METHODS: A structured literature search was undertaken to identify randomised controlled trials (RCTs) conducted in RA patients receiving either statins or control. A meta-analysis on standardised mean difference (SMD) with a 95% confidence interval (95%CI) was conducted. RESULTS: We included 15 studies with a total of 992 patients (487 patients allocated to statins therapy). Our data revealed statins can attenuate disease activity markedly. Overall, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) declined significantly during the treatment (n=12, SMD: -2.222, 95%CI: -2.404, -2.040, p=0.000; n=14, SMD: -3.014, 95%CI: -3.207, -2.821, p=0.000), among which ESR and CRP decreased obviously at 12 months (n=5, SMD: -2.874, 95%CI: -3.224, -2.523, p=0.000; n=7, SMD: -3.970, 95%CI: -4.300, -3.641, p=0.000; respectively). As expected, the tender joint count (TJC) and swollen joint count (SJC) also fell (n=9, SMD: -2.005, 95% CI: -2.216, -1.794; p=0.000; n=10, SMD: -1.76, 95%CI: -1.948, -1.577; p=0.000; respectively). Besides, morning stiffness was attenuated (n=5, SMD: -1.242, 95%CI: -1.474, -1.011, p=0.000), and showed no significant differences between 12 months and 24 months (p=0.205). Notably, statins indeed potently down-regulate inflammatory factors TNF-α (n=7, SMD: -4.290, 95%CI: -4.659, -3.922; p=0.000), IL-1 (n=4, SMD: -1.324, 95%CI: -1.646, -1.003; p=0.000), and IL-6 (n=10, SMD: -1.652, 95%CI: -1.822, -1.482; p=0.000). No publication bias was observed across all studies based on the Begg and Egger test. CONCLUSIONS: This meta-analysis demonstrates the pleiotropic effects of statins on ameliorating RA activity and mediating clinically apparent anti-inflammatory effects in the context of RA autoimmune inflammation, which make it recommended as a potent treatment for RA patients.


Asunto(s)
Antiinfecciosos/uso terapéutico , Artritis Reumatoide/tratamiento farmacológico , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Mediadores de Inflamación/sangre , Artritis Reumatoide/sangre , Artritis Reumatoide/diagnóstico , Artritis Reumatoide/inmunología , Autoinmunidad/efectos de los fármacos , Biomarcadores/sangre , Sedimentación Sanguínea , Evaluación de la Discapacidad , Humanos , Articulaciones/efectos de los fármacos , Articulaciones/patología , Inducción de Remisión , Factores de Tiempo , Resultado del Tratamiento
8.
Sheng Li Xue Bao ; 67(6): 611-7, 2015 Dec 25.
Artículo en Zh | MEDLINE | ID: mdl-26701637

RESUMEN

The aim of this study was to investigate the effects of digoxin on the chemoresistance of human breast cancer cell line MCF-7/adriamycin (ADR) and its underlying mechanism. MCF-7 and MCF-7/ADR cells were designated as control and ADR groups, respectively. MCF-7/ADR cells in ADR + digoxin group received 48 h of digoxin (10 nmol/L) treatment; MCF-7/ADR cells transfected with pLKO.1-shHIF-1α and pLKO.1-shcontrol plasmids were named shHIF-1α and shcontrol groups, respectively. CCK-8 assay was employed to detect the cytotoxic effect of ADR on MCF-7/ADR cells, and IC50 value and resistance index were calculated according to CCK-8. RT-PCR was used to measure the mRNA levels of hypoxia inducible factor-1α (HIF-1α) and multidrug resistance-1 (MDR1). Western blot was used to analyze the protein levels of HIF-1α and MDR1. Flow cytometry was used to determine the apoptosis. The result showed that the resistance index of MCF-7/ADR cells was 115.6, and it was reduced to 47.2 under the action of digoxin (P < 0.05). In comparison with control group, ADR groups showed increased protein and mRNA levels of HIF-1α and MDR1 (P < 0.05). Digoxin reduced the protein levels of HIF-1α and MDR1, as well as the mRNA level of MDR1, but did not affect the mRNA level of HIF-1α. After HIF-1α gene was silenced, the protein levels of HIF-1α and MDR1 were down-regulated (P < 0.05), and the pro-apoptotic effect of ADR on MCF-7/ADR cells was enhanced. Although it was also observed that digoxin promoted cell apoptosis in both shcontrol and shHIF-1α groups, the difference between the two groups was not significant. In conclusion, the results suggest that digoxin may partially reverse the ADR resistance in human breast cancer cell line MCF-7/ADR by means of down-regulating the expression levels of HIF-1α and MDR1 and promoting apoptosis via HIF-1α-independent pathway.


Asunto(s)
Digoxina/farmacología , Doxorrubicina/farmacología , Resistencia a Antineoplásicos , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Apoptosis , Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Humanos , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Células MCF-7/efectos de los fármacos , ARN Mensajero , Transfección
9.
Tumour Biol ; 35(12): 12435-40, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25185652

RESUMEN

Papillary thyroid microcarcinoma (PMC) is the most common subtype of thyroid carcinomas with satisfactory prognosis. Crk-like (CrkL) adaptor protein was identified in the development of many carcinomas. However, the clinical implications of CrkL protein in PMC were still unknown. Here, we conducted immunohistochemistry to test and analyze CrkL expression in papillary thyroid carcinoma (PTC) (50 cases), PMC (50 cases), and nodular goiter (50 cases), and then western blot further identified the expression of CrkL proteins. In our present study, the positive rate and the mean optical density (MOD) value of CrkL expression in PTC and PMC tissues were statistically significantly different, compared with nodular goiter (p = 0.021, 0.037) and normal thyroid tissues (p = 0.003, 0.009), respectively. In addition, CrkL expression was not associated with age, gender, and tumor number. Conversely, significant differences between CrkL expression and metastasis (p < 0.01) and violation of capsule (p < 0.01) were observed. Notably, western blot indeed identified that the metastasis group of either PTC or PMC tissues had about twofold increased expression of CrkL compared with their non-metastasis groups (p < 0.05). In conclusion, CrkL is highly expressed in papillary thyroid carcinoma and papillary thyroid microcarcinoma and closely correlated to metastasis. Therefore, it is essential to carry out neck lymph node clearance in patients with papillary thyroid microcarcinoma.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/metabolismo , Carcinoma Papilar/metabolismo , Proteínas Nucleares/metabolismo , Neoplasias de la Tiroides/metabolismo , Proteínas Adaptadoras Transductoras de Señales/genética , Adulto , Anciano , Carcinoma/genética , Carcinoma/metabolismo , Carcinoma/patología , Carcinoma Papilar/genética , Carcinoma Papilar/patología , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Metástasis Linfática , Masculino , Persona de Mediana Edad , Proteínas Nucleares/genética , Pronóstico , Reproducibilidad de los Resultados , Cáncer Papilar Tiroideo , Neoplasias de la Tiroides/genética , Neoplasias de la Tiroides/patología , Adulto Joven
10.
Sheng Li Xue Bao ; 66(5): 625-30, 2014 Oct 25.
Artículo en Zh | MEDLINE | ID: mdl-25332010

RESUMEN

The aim of this study was to investigate the effects of AEG-1 gene silencing on the chemoresistance of human breast cancer cell line MCF-7/ADM and its possible mechanism. MCF-7/ADM cells were incubated in the medium containing adriamycin (ADM). The recombinant pLKO.1-shAEG-1 plasmid was constructed to silence AEG-1 expression in human breast cancer MCF-7/ADM cells. MTT assay was employed to detect the anti-tumor effect of ADM on MCF-7/ADM cells, and IC50 value of ADM was calculated according to MTT. Flow cytometry was used to determine the apoptosis. Western blot was used to analyze the expression levels of AEG-1, p-Akt, p-MDM2, p-Bad, p53 and MDR1. The result showed MCF-7/ADM had a significantly higher expression level of AEG-1 compared with that of MCF-7 (P < 0.05), however, the expression of AEG-1 was decreased after AEG-1 gene silencing. The IC50 value of ADM in shAEG-1 group was significantly lower than that in shcontrol group. AEG-1 gene silencing induced cell apoptosis and enhanced the pro-apoptotic effect of ADM on MCF-7/ADM cells. After AEG-1 gene silencing, the phosphorylation of Akt, MDM2 and Bad was inhibited (P < 0.05), the protein levels of p53 and MDR1 were up-regulated (P < 0.05) and down-regulated (P < 0.05) respectively, compared with control. In conclusion, the results suggest that AEG-1 gene silencing can reverse the ADM resistance in human breast cancer cell line MCF-7/ADM by means of inducing apoptosis and down-regulating the protein level of MDR1.


Asunto(s)
Moléculas de Adhesión Celular/genética , Doxorrubicina/farmacología , Resistencia a Antineoplásicos/genética , Silenciador del Gen , Apoptosis , Neoplasias de la Mama/genética , Neoplasias de la Mama/metabolismo , Moléculas de Adhesión Celular/metabolismo , Humanos , Células MCF-7 , Proteínas de la Membrana , Proteínas de Unión al ARN
11.
Biochem Pharmacol ; 223: 116162, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38527557

RESUMEN

Immune checkpoint inhibitors have unveiled promising clinical prospects in cancer treatment. Nonetheless, their effectiveness remains restricted, marked by consistently low response rates and affecting only a subset of patients. The co-blockade of TIGIT with PD-1 has exhibited substantial anti-tumor effects. Notably, there is a dearth of reports on small-molecule inhibitors concurrently targeting both TIGIT and PD-1. In this study, we employed Microscale Thermophoresis (MST) to screen our laboratory's existing repository of small molecules. Our findings illuminated Gln(TrT) 's affinity for both TIGIT and PD-1, affirming its potential to effectively inhibit TIGIT/PVR and PD-1/PD-L1 pathways. In vitro co-culture experiments substantiated Gln(TrT)'s proficiency in restoring Jurkat T-cell functionality by blocking both TIGIT/PVR and PD-1/PD-L1 interactions. In the MC38 murine tumor model, Gln(TrT) emerges as a pivotal modulator, promoting the intratumoral infiltration and functional competence of CD8+ T cells. Furthermore, whether used as a monotherapy or in conjunction with radiotherapy, Gln(TrT) substantially impedes MC38 tumor progression, significantly extending the survival of murine subjects.


Asunto(s)
Linfocitos T CD8-positivos , Neoplasias , Humanos , Animales , Ratones , Receptor de Muerte Celular Programada 1/metabolismo , Antígeno B7-H1/metabolismo , Receptores Inmunológicos , Inmunoterapia , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo
12.
Cancer Immunol Immunother ; 62(11): 1723-32, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24077852

RESUMEN

PIWIL2, a member of PIWI/AGO family, is expressed in germline stem cells and precancerous stem cells, but not in adult somatic cells. PIWIL2 plays an important role in tumor development. It is considered as a cancer­testis antigen (CT80). It has been reported that the spliced fragment of PIWIL2, PL2L60, was widely expressed in cancer cell lines. In this study, HLA-A2-restricted epitopes from PL2L60 were predicted by online tools. To improve the activity of the native epitope, a candidate peptide P281 with potent binding affinity was chosen to investigate the modification strategy. A series of aromatic amino acids were introduced to substitute the first residue of P281. Then, we tested the binding affinity and stability of the peptide analogs and their ability to elicit specific immune responses both in vitro and in vivo. Our results indicated that the cytotoxic T lymphocytes (CTLs) induced by [4-Cl-Phe1]P281 could elicit more potent activities than that of P281 and other analogs. The CTLs induced by this analog could lyze target cells in HLA-A2-restricted and antigen-specific manners. [4-Cl-Phe1]P281 also showed the best resistance against degradation in human serum. In conclusion, the introduction of the unnatural amino acid, 4-Cl-Phe, into the first position could enhance the activity of the native epitope to induce cytotoxic T lymphocytes. It might be a good strategy to modify other promising native epitopes. The novel epitopes identified in this study could be used as novel candidates to the immunotherapy of HLA-A2 positive patients with tumors expressing PL2L60.


Asunto(s)
Proteínas Argonautas/inmunología , Epítopos de Linfocito T/inmunología , Péptidos/inmunología , Linfocitos T Citotóxicos/inmunología , Empalme Alternativo , Secuencia de Aminoácidos , Sustitución de Aminoácidos , Animales , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/inmunología , Antígenos de Neoplasias/metabolismo , Proteínas Argonautas/genética , Proteínas Argonautas/metabolismo , Western Blotting , Línea Celular , Citotoxicidad Inmunológica/inmunología , Epítopos de Linfocito T/genética , Epítopos de Linfocito T/metabolismo , Regulación Neoplásica de la Expresión Génica , Antígeno HLA-A2/inmunología , Células HT29 , Humanos , Interferón gamma/inmunología , Interferón gamma/metabolismo , Células MCF-7 , Ratones , Ratones Transgénicos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/patología , Péptidos/genética , Péptidos/metabolismo , Fenilalanina/genética , Fenilalanina/inmunología , Fenilalanina/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Linfocitos T Citotóxicos/metabolismo
14.
Materials (Basel) ; 16(17)2023 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-37687458

RESUMEN

Enhancing the conductivity loss of SiC nanowires through doping is beneficial for improving their electromagnetic wave absorption performance. In this work, N-doped SiC nanowires were synthesized using three different methods. The results indicate that a large amount of Si2ON will be generated during the microwave synthesis of SiC nanowires in a nitrogen atmosphere. In addition, the secondary heat-treatment of the as-synthesized SiC nanowires under nitrogen atmosphere will significantly reduce their stacking fault density. When ammonium chloride is introduced as a doped nitrogen source in the reaction raw material, the N-doped SiC nanowires with high-density stacking faults can be synthesized by microwave heating. Therefore, the polarization loss induced by faults and the conductivity loss caused by doping will synergistically enhance the dielectric and EMW absorption properties of SiC nanowires in the range of 2-18 GHz. When the filling ratio of N-doped SiC nanowires is 20 wt.%, the composite shows a minimum reflection loss of -22.2 dB@17.92 GHz, and an effective absorption (RL ≤ -10 dB) bandwidth of 4.24 GHz at the absorber layer thickness of 2.2 mm. Further, the N-doped SiC nanowires also exhibit enhanced high-temperature EMW absorption properties with increasing temperature.

15.
Thyroid ; 33(9): 1055-1063, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37566523

RESUMEN

Background: Preterm infants presented a high prevalence of congenital hypothyroidism (CH), while the optimal screening pattern is still under debate. This study aimed at evaluating the characteristics of thyroid function by conducting weekly screening during the first month of life in very preterm infants (VPIs) to achieve timely diagnosis and treatment of CH. Methods: A prospective cohort study was carried out on VPIs born with gestational age (GA) <32 weeks (w) and admitted to the participating institutes from January 1, 2019 to December 31, 2022. Serial serum thyroid hormone levels were measured weekly within the first month after birth, and at 36 w of corrected age, or before discharge. Datasets for serial thyroid hormone levels and general information were obtained. Results: A total of 5992 VPIs were enrolled in this study, of which 456 (7.6%) [95% confidence interval (CI), 6.9-8.3%] were diagnosed with CH. The incidence of CH increased with lower GA, moving from 4.8% [CI, 3.4-6.1%] at GA 31 w to 16.9% [CI, 8.3-25.4%] at GA <26 w. Among the CH subjects, 57.7% [CI, 53.1-62.2%] were identified after the first screening and classified as delayed thyrotropin elevation (dTSH). With the decrease of GA, the proportion of dTSH also increased, moving from 38.1% [CI, 27.5-48.7%] at GA 31 w to 82.6% [CI, 65.8-99.4%] at GA <26 w. Through conducting weekly screening of thyroid function, it was remarkable that only 42.3% [CI, 37.8-46.9%] of CH subjects were diagnosed during the first screening. The cumulative rate of CH identified by rescreening performed at the second, third, and fourth week was 76.1% [CI, 72.2-80.0%], 90.6% [CI, 87.9-93.3%], and 98.9% [CI, 97.9-99.9%], respectively. Conclusion: The incidence of CH and dTSH both increase with lower GA in VPIs. Dynamic screening of thyroid function by weeks within the first month of life is crucial for the timely diagnosis and treatment of CH in VPIs, and it might effectively reduce the implications of missed diagnosis and delayed treatment. Clinical Trials Registration: ChiCTR1900025234 and ChiCTR2000037918 (Registration number).


Asunto(s)
Hipotiroidismo Congénito , Lactante , Recién Nacido , Humanos , Hipotiroidismo Congénito/diagnóstico , Hipotiroidismo Congénito/epidemiología , Recien Nacido Prematuro , Estudios Prospectivos , Tiroxina , Tamizaje Neonatal , Hormonas Tiroideas/uso terapéutico , Tirotropina
16.
Food Chem ; 385: 132697, 2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35306236

RESUMEN

This study developed a sensitive and easy method to directly analyze Nε-(carboxymethyl)lysine (CML) by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Acetonitrile and water were used as the binary mobile phase without ion pair reagents, while BEH Amide column was applied to detect CML. The target substance without derivatization could be well retained and separated after the pretreatment conditions were optimized. Oasis MCX solid phase extraction (SPE) cartridge showed the best recovery rate of CML 96.7 % and purification ability among the tested SPE cartridges. There was no obvious difference in pretreatment abilities with or without protein precipitation on the CML quantitative analysis. The recovery rates 97-98 % for CML were achieved by UPLC-MS/MS, as well as the detection limit and quantification limit were 0.05 mg/kg and 0.15 mg/kg sample, respectively. This method was suitable for quantifying CML content with high recovery rate and low detection and quantification limit in sterilized milk.


Asunto(s)
Leche , Espectrometría de Masas en Tándem , Animales , Cromatografía Líquida de Alta Presión , Cromatografía Liquida , Indicadores y Reactivos , Isótopos , Lisina/análogos & derivados , Extracción en Fase Sólida
17.
Cell Death Dis ; 13(5): 501, 2022 05 25.
Artículo en Inglés | MEDLINE | ID: mdl-35614059

RESUMEN

The antioxidant transcription factor NFE2L1 (also called Nrf1) acts as a core regulator of redox signaling and metabolism homeostasis, and thus, its dysfunction results in multiple systemic metabolic diseases. However, the molecular mechanism(s) by which NFE2L1 regulates glycose and lipid metabolism remains elusive. Here, we found that loss of NFE2L1 in human HepG2 cells led to a lethal phenotype upon glucose deprivation and NFE2L1 deficiency could affect the uptake of glucose. Further experiments revealed that glycosylation of NFE2L1 enabled it to sense the energy state. These results indicated that NFE2L1 can serve as a dual sensor and regulator of glucose homeostasis. The transcriptome, metabolome, and seahorse data further revealed that disruption of NFE2L1 could reprogram glucose metabolism to aggravate the Warburg effect in NFE2L1-silenced hepatoma cells, concomitant with mitochondrial damage. Co-expression and Co-immunoprecipitation experiments demonstrated that NFE2L1 could directly interact and inhibit AMPK. Collectively, NFE2L1 functioned as an energy sensor and negatively regulated AMPK signaling through directly interacting with AMPK. The novel NFE2L1/AMPK signaling pathway delineate the mechanism underlying of NFE2L1-related metabolic diseases and highlight the crosstalk between redox homeostasis and metabolism homeostasis.


Asunto(s)
Proteínas Quinasas Activadas por AMP , Factor 1 Relacionado con NF-E2 , Proteínas Quinasas Activadas por AMP/metabolismo , Metabolismo Energético , Glucosa , Homeostasis , Factor 1 Relacionado con NF-E2/metabolismo , Transducción de Señal
18.
Sci China Life Sci ; 65(3): 572-587, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-34236583

RESUMEN

Colorectal cancer has one of the highest mortality rates among malignant tumors, and most patients with non-microsatellite instability-high (MSI-H) colorectal cancer do not benefit from targeted therapy or immune checkpoint inhibitors. Identification of immunogenic neoantigens is a promising strategy for inducing specific antitumor T cells for cancer immunotherapy. Here, we screened potential high-frequency neoepitopes from non-MSI-H colorectal cancer and tested their abilities to induce tumor-specific cytotoxic T cell responses. Three HLA-A2-restricted neoepitopes (P31, P50, and P52) were immunogenic and could induce cytotoxic T lymphocytes in peripheral blood mononuclear cells from healthy donors and colorectal cancer patients. Cytotoxic T lymphocytes induced in HLA-A2.1/Kb transgenic mice could recognize and lyse mutant neoepitope-transfected HLA-A2+ cancer cells. Adoptive transfer of cytotoxic T lymphocytes induced by the peptide pool of these three neoepitopes effectively inhibited tumor growth and increased the therapeutic effects of anti-PD-1 antibody. These results revealed the potential of high-frequency mutation-specific peptide-based immunotherapy as a personalized treatment approach for patients with non-MSI-H colorectal cancer. The combination of adoptive T cell therapy based on these neoepitopes with immune checkpoint inhibitors, such as anti-PD-1, could provide a promising treatment strategy for non-MSI-H colorectal cancer.


Asunto(s)
Neoplasias Colorrectales/terapia , Epítopos/inmunología , Antígeno HLA-A2/inmunología , Inmunoterapia Adoptiva , Inestabilidad de Microsatélites , Linfocitos T Citotóxicos/inmunología , Animales , Línea Celular Tumoral , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/inmunología , Femenino , Humanos , Ratones , Mutación
19.
J Immunother Cancer ; 10(11)2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36323433

RESUMEN

BACKGROUND: The development of cancer is largely dependent on the accumulation of somatic mutations, indicating the potential to develop cancer chemoprevention agents targeting mutation drivers. However, ideal cancer chemoprevention agents that can effectively inhibit the mutation drivers have not been identified yet. METHODS: The somatic mutation signatures and expression analyses of APOBEC3B were performed in patient with pan-cancer. The computer-aided screening and skeleton-based searching were performed to identify natural products that can inhibit the activity of APOBEC3B. 4-nitroquinoline-1-oxide (4-NQO)-induced spontaneous esophageal squamous cell carcinoma (ESCC) and azoxymethane/dextran sulfate sodium (AOM/DSS)-induced spontaneous colon cancer mouse models were conducted to investigate the influences of APOBEC3B inhibitor on the prevention of somatic mutation accumulation and cancer progression. RESULTS: Here, we discovered that the cytidine deaminase APOBEC3B correlated somatic mutations were widely observed in a variety of cancers, and its overexpression indicated poor survival. SMC247 (3, 5-diiodotyrosine), as a source of kelp iodine without side effects, could strongly bind APOBEC3B (KD=65 nM) and effectively inhibit its deaminase activity (IC50=1.69 µM). Interestingly, 3, 5-diiodotyrosine could significantly reduce the clusters of mutations, prevent the precancerous lesion progression, and prolong the survival in 4-NQO-induced spontaneous ESCC and AOM/DSS-induced spontaneous colon cancer mouse models. Furthermore, 3, 5-diiodotyrosine could reduce colitis, increase the proportion and function of T lymphocytes via IL-15 in tumor microenvironment. The synergistic cancer prevention effects were observed when 3, 5-diiodotyrosine combined with PD-1/PD-L1 blockade. CONCLUSIONS: This is the first prove-of-concept study to elucidate that the natural product 3, 5-diiodotyrosine could prevent somatic mutation accumulation and cancer progression through inhibiting the enzymatic activity of APOBEC3B. In addition, 3, 5-diiodotyrosine could reduce the colitis and increase the infiltration and function of T lymphocytes via IL-15 in tumor microenvironment. 3, 5-diiodotyrosine combined with PD-1/PD-L1 blockade could elicit synergistic cancer prevention effects, indicating a novel strategy for both prevent the somatic mutation accumulation and the immune-suppressive microenvironment exacerbation.


Asunto(s)
Productos Biológicos , Colitis , Neoplasias del Colon , Neoplasias Esofágicas , Carcinoma de Células Escamosas de Esófago , Animales , Ratones , Azoximetano , Antígeno B7-H1/genética , Colitis/inducido químicamente , Diyodotirosina/genética , Interleucina-15/genética , Antígenos de Histocompatibilidad Menor/genética , Acumulación de Mutaciones , Receptor de Muerte Celular Programada 1/genética , Microambiente Tumoral
20.
J Food Sci ; 86(10): 4628-4636, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34549438

RESUMEN

This study investigated the effect of antioxidants on lipid stability of mackerel (Scomber japonicus) fish balls. Oat phenolic acid compounds (OPC) and ascorbate palmitoyl (AP) were used to prolong the shelf life of steamed mackerel fish balls. Fish balls were stored at 4°C for 21 days, and the total bacterial count, hardness, whiteness, water holding capacity (WHC), pH, total volatile basic nitrogen (TVB-N), and thiobarbituric acid reactive substances (TBARS) value were monitored regularly. The results indicated that OPC+AP composite as a biological preservative could significantly inhibit the increase of the total bacterial count. Meanwhile, OPC and AP could maintain better hardness, whiteness, and WHC of fish balls during refrigerated storage. Furthermore, OPC and AP slowed down the increase of TVB-N and TBARS values. The results showed that OPC+AP had a synergistic effect on the storage time and could prolong the shelf life within the storage time. Adding OPC and AP was a promising strategy to improve the quality and shelf life of fish balls. PRACTICAL APPLICATION: The research provided a new application of OPC and AP for improving fish balls quality and shelf life during cold storage (4°C). OPC is a natural plant secondary metabolite from oat which exhibits excellent anti-oxidation. The research showed that OPC and AP combined with synergistic effect as biological preservatives can effectively inhibit the total bacterial count and reduce TBARS and TVB-N value of fish balls during the shelf life and maintain the hardness, which improved the quality and shelf life of fish balls.


Asunto(s)
Ácido Ascórbico/análogos & derivados , Avena , Productos Pesqueros , Conservación de Alimentos , Fenoles , Animales , Antiinfecciosos/farmacología , Antioxidantes/farmacología , Ácido Ascórbico/farmacología , Avena/química , Carga Bacteriana/efectos de los fármacos , Frío , Productos Pesqueros/análisis , Productos Pesqueros/microbiología , Productos Pesqueros/normas , Conservación de Alimentos/métodos , Almacenamiento de Alimentos , Oxidación-Reducción/efectos de los fármacos , Fenoles/farmacología
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