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1.
Molecules ; 29(9)2024 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-38731530

RESUMEN

Hydroformylation of olefins is widely used in the chemical industry due to its versatility and the ability to produce valuable aldehydes with 100% atom economy. Herein, a hybrid phosphate promoter was found to efficiently promote rhodium-catalyzed hydroformylation of styrenes under remarkably mild conditions with high regioselectivities. Preliminary mechanistic studies revealed that the weak coordination between the Rhodium and the P=O double bond of this pentavalent phosphate likely induced exceptional reactivity and high ratios of branched aldehydes to linear products.

2.
Gynecol Oncol ; 180: 99-110, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38086167

RESUMEN

BACKGROUND: Cisplatin (DDP)-based chemotherapy is a common chemotherapeutic regimen for the treatment of advanced epithelial ovarian cancer (EOC). However, most patients rapidly develop chemoresistance. N6-methyladenosine (m6A) is a pervasive RNA modification, and its specific role and potential mechanism in the regulation of chemosensitivity in EOC remain unclear. METHODS: The expression of RIPK4 and its clinicopathological impact were evaluated in EOC cohorts. The biological effects of RIPK4 were investigated using in vitro and in vivo models. RNA m6A quantification was used to measure total m6A levels in epithelial ovarian cancer cells. Luciferase reporter, MeRIP-qPCR, RIP-qPCR and actinomycin-D assays were used to investigate RNA/RNA interactions and m6A modification of RIPK4 mRNA. RESULTS: We demonstrated that RIPK4, an upregulated mRNA in EOC, acts as an oncogene in EOC cells by promoting tumor cell proliferation and DDP resistance at the clinical, database, cellular, and animal model levels. Mechanistically, METTL3 facilitates m6A modification, and YTHDF1 recognizes the specific m6A-modified site to prevent RIPK4 RNA degradation and upregulate RIPK4 expression. This induces NF-κB activation, resulting in tumor growth and DDP resistance in vitro and in vivo. CONCLUSIONS: Collectively, the present findings reveal a novel mechanism underlying the induction of DDP resistance by m6A-modified RIPK4, that may contribute to overcoming chemoresistance in EOC.


Asunto(s)
Adenina , Cisplatino , Neoplasias Ováricas , Animales , Femenino , Humanos , Adenina/análogos & derivados , Carcinoma Epitelial de Ovario/tratamiento farmacológico , Proliferación Celular , Cisplatino/farmacología , Metiltransferasas/genética , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , ARN , ARN Mensajero
3.
Sci Bull (Beijing) ; 69(1): 82-96, 2024 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-38030520

RESUMEN

Efficient immune responses rely on the proper differentiation of CD8+ T cells into effector and memory cells. Here, we show a critical requirement of N6-Methyladenosine (m6A) methyltransferase Mettl3 during CD8+ T cell responses upon acute viral infection. Conditional deletion of Mettl3 in CD8+ T cells impairs effector expansion and terminal differentiation in an m6A-dependent manner, subsequently affecting memory formation and the secondary response of CD8+ T cells. Our combined RNA-seq and m6A-miCLIP-seq analyses reveal that Mettl3 deficiency broadly impacts the expression of cell cycle and transcriptional regulators. Remarkably, Mettl3 binds to the Tbx21 transcript and stabilizes it, promoting effector differentiation of CD8+ T cells. Moreover, ectopic expression of T-bet partially restores the defects in CD8+ T cell differentiation in the absence of Mettl3. Thus, our study highlights the role of Mettl3 in regulating multiple target genes in an m6A-dependent manner and underscores the importance of m6A modification during CD8+ T cell response.


Asunto(s)
Linfocitos T CD8-positivos , Metiltransferasas , Diferenciación Celular/genética , Metiltransferasas/genética
4.
Abdom Radiol (NY) ; 49(1): 258-270, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37987856

RESUMEN

PURPOSE: To establish and validate a deep learning radiomics nomogram (DLRN) based on intratumoral and peritumoral regions of MR images and clinical characteristics to predict recurrence risk factors in early-stage cervical cancer and to clarify whether DLRN could be applied for risk stratification. METHODS: Two hundred and twenty five pathologically confirmed early-stage cervical cancers were enrolled and made up the training cohort and internal validation cohort, and 40 patients from another center were enrolled into the external validation cohort. On the basis of region of interest (ROI) of intratumoral and different peritumoral regions, two sets of features representing deep learning and handcrafted radiomics features were created using combined images of T2-weighted MRI (T2WI) and diffusion-weighted imaging (DWI). The signature subset with the best discriminant features was chosen, and deep learning and handcrafted signatures were created using logistic regression. Integrated with independent clinical factors, a DLRN was built. The discrimination and calibration of DLNR were applied to assess its therapeutic utility. RESULTS: The DLRN demonstrated satisfactory performance for predicting recurrence risk factors, with AUCs of 0.944 (95% confidence interval 0.896-0.992) and 0.885 (95% confidence interval 0.834-0.937) in the internal and external validation cohorts. Furthermore, decision curve analysis revealed that the DLRN outperformed the clinical model, deep learning signature, and radiomics signature in terms of net benefit. CONCLUSION: A DLRN based on intratumoral and peritumoral regions had the potential to predict and stratify recurrence risk factors for early-stage cervical cancers and enhance the value of individualized precision treatment.


Asunto(s)
Aprendizaje Profundo , Neoplasias del Cuello Uterino , Humanos , Femenino , Neoplasias del Cuello Uterino/diagnóstico por imagen , Nomogramas , Radiómica , Imagen por Resonancia Magnética , Factores de Riesgo , Estudios Retrospectivos
5.
Angew Chem Int Ed Engl ; 63(4): e202313952, 2024 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-37994255

RESUMEN

16ß-Methylcorticoids are among the most important glucocorticoid steroids for the treatment of various dermatological disorders, respiratory infections, and other allergic reactions elicited during inflammatory responses of the human body. Betamethasone dipropionate, clobetasol propionate, and beclomethasone dipropionate are particularly noteworthy for their synthetic intractability. Despite five decades of research, these 16ß-methylcorticoids have remained challenging synthetic targets owing to insurmountable issues of reactivity, selectivity, and cost efficiency associated with all previously explored strategies. We herein report our practicability-oriented strategy toward the unified stereoselective synthesis of 16ß-methylcorticoids in 12.6-14.0 % overall yield from commercially available 9α-hydroxyandrost-4-ene-3,17-dione (9α-OH-AD). In this approach, the chiral C16ß-Me and C17α-OH groups of the corticosteroid D ring were installed via a substrate-controlled diastereo- and enantioselective Mn-catalyzed oxidation-reduction hydration of Δ4,9(11),16 -triene-3,20-dione. The C1-C2 double bond of the corticosteroid A ring was constructed using an unprecedented engineered 3-ketosteroid-Δ1 -dehydrogenase (MK4-KstD)-catalyzed regioselective Δ1 -dehydrogenation of Δ4,9(11) -diene-3,21-dione. This strategy provides a general method and a key precursor for the divergent synthesis of a variety of glucocorticoids and related steroidal drugs.


Asunto(s)
Beclometasona , Clobetasol , Humanos , Clobetasol/uso terapéutico , Betametasona/uso terapéutico , Esteroides , Corticoesteroides
6.
Heliyon ; 9(9): e19302, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37662748

RESUMEN

Basil seed gum (BSG) is a new hydrophilic colloid of natural plant origin. Extracted from basil seeds, it possesses excellent functional characteristics in terms of emulsification, rheology, gelation, stability, and adsorption, which are just as favorable as those of certain commercial gums. Besides, BSG has been widely used in food, medicine, industry, and many other fields for its physiological functions of weight reduction, detoxification, and control of blood sugar and cholesterol as a good dietary fiber. In this paper, we analyzed and discussed the extraction procedures, composition structures, functional characteristics, and modification strategies of BSG. In addition, we summarized the latest research on the applications of BSG in different industries to provide theoretical references for the high-value processing and utilization of BSG.

7.
Chem Res Toxicol ; 36(9): 1495-1502, 2023 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-37625021

RESUMEN

Alkylation reagents, represented by sulfur mustard (SM), can damage DNA molecules directly as well as lead to oxidative stress, causing DNA lesions indirectly. Correspondingly, two types of biomarkers including alkylated DNA adducts and oxidative DNA adducts are commonly involved in the research of DNA damage evaluation caused by these agents. However, the correlations and differences of the occurrence, duration, severity, and traceability between alkylation and oxidation lesions on the DNA molecular level reflected by these two types of biomarkers have not been systematically studied. A simultaneous determination method for four alkylated DNA adducts, i.e., N7-(2-hydroxyethylthioethyl)2'-guanine (N7-HETEG), O6-(2-hydroxyethylthioethyl)-2'-guanine (O6-HETEG), N3-(2-hydroxyethylthioethyl)-2'-adenine (N3-HETEA), and bis(2-ethyl-N7-guanine)thioether (Bis-G), and the oxidative adduct 8-hydroxy-2'-deoxyguanosine (8-OH-dG) in urine samples by isotope-dilution high-performance liquid chromatography-tandem mass spectrometry (ID-HPLC-MS/MS) was built with a lower limit of detection of 0.02 ng/mL (except Bis-G, 0.05 ng/mL) and a recovery of 79-111%. The profile of these adducts was simultaneously monitored in urine samples after SD rats' dermal exposure to SM in three dose levels (1, 3, and 10 mg/kg). The time-effect and dose-effect experiments revealed that when exposed to SM, DNA alkylation lesions would happen earlier than those of oxidation. For the two types of biomarkers, alkylated DNA adducts showed an obvious dose-effect relationship and could be used as internal exposure dose and effect biomarkers, while 8-OH-dG did not show a correlation with exposure dose, demonstrating that it was more suitable as a biomarker for DNA oxidative lesions but not an indicator for the extent of cytotoxicity and internal exposure.


Asunto(s)
Aductos de ADN , Gas Mostaza , Animales , Ratas , Ratas Sprague-Dawley , Gas Mostaza/toxicidad , 8-Hidroxi-2'-Desoxicoguanosina , Espectrometría de Masas en Tándem , Estrés Oxidativo , Guanina
8.
Cell Rep ; 42(6): 112584, 2023 06 27.
Artículo en Inglés | MEDLINE | ID: mdl-37267102

RESUMEN

N6-methyladenosine (m6A) methyltransferase Mettl3 is involved in conventional T cell immunity; however, its role in innate immune cells remains largely unknown. Here, we show that Mettl3 intrinsically regulates invariant natural killer T (iNKT) cell development and function in an m6A-dependent manner. Conditional ablation of Mettl3 in CD4+CD8+ double-positive (DP) thymocytes impairs iNKT cell proliferation, differentiation, and cytokine secretion, which synergistically causes defects in B16F10 melanoma resistance. Transcriptomic and epi-transcriptomic analyses reveal that Mettl3 deficiency disturbs the expression of iNKT cell-related genes with altered m6A modification. Strikingly, Mettl3 modulates the stability of the Creb1 transcript, which in turn controls the protein and phosphorylation levels of Creb1. Furthermore, conditional targeting of Creb1 in DP thymocytes results in similar phenotypes of iNKT cells lacking Mettl3. Importantly, ectopic expression of Creb1 largely rectifies such developmental defects in Mettl3-deficient iNKT cells. These findings reveal that the Mettl3-m6A-Creb1 axis plays critical roles in regulating iNKT cells at the post-transcriptional layer.


Asunto(s)
Diferenciación Celular , Células T Asesinas Naturales , Diferenciación Celular/genética , Metiltransferasas , Proteínas , Timocitos , Animales , Ratones
9.
Diagnostics (Basel) ; 13(6)2023 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-36980381

RESUMEN

Purpose: This study aimed to establish a deep learning radiomics nomogram (DLRN) based on multiparametric MR images for predicting the response to neoadjuvant chemotherapy (NACT) in patients with locally advanced cervical cancer (LACC). Methods: Patients with LACC (FIGO stage IB-IIIB) who underwent preoperative NACT were enrolled from center 1 (220 cases) and center 2 (independent external validation dataset, 65 cases). Handcrafted and deep learning-based radiomics features were extracted from T2WI, DWI and contrast-enhanced (CE)-T1WI, and radiomics signatures were built based on the optimal features. Two types of radiomics signatures and clinical features were integrated into the DLRN for prediction. The AUC, calibration curve and decision curve analysis (DCA) were employed to illustrate the performance of these models and their clinical utility. In addition, disease-free survival (DFS) was assessed by Kaplan-Meier survival curves based on the DLRN. Results: The DLRN showed favorable predictive values in differentiating responders from nonresponders to NACT with AUCs of 0.963, 0.940 and 0.910 in the three datasets, with good calibration (all p > 0.05). Furthermore, the DLRN performed better than the clinical model and handcrafted radiomics signature in all datasets (all p < 0.05) and slightly higher than the DL-based radiomics signature in the internal validation dataset (p = 0.251). DCA indicated that the DLRN has potential in clinical applications. Furthermore, the DLRN was strongly correlated with the DFS of LACC patients (HR = 0.223; p = 0.004). Conclusion: The DLRN performed well in preoperatively predicting the therapeutic response in LACC and could provide valuable information for individualized treatment.

10.
Front Oncol ; 12: 956289, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36052269

RESUMEN

Objective: To analyze the clinical features, ultrasonographic manifestations, pathological features, treatment and prognosis of primary thyroid squamous cell carcinoma (PSCTC) and summarize the experience in diagnosis and treatment of this condition. Methods: A retrospective analysis was conducted on patients who were admitted to Zhejiang Cancer Hospital from 2007 to 2021 due to thyroid nodules or thyroid malignant tumors that were ultimately confirmed by postoperative pathology as primary thyroid squamous cell carcinoma. We summarize the general situation, clinical information, laboratory examination, ultrasonic image characteristics, pathological examination, clinical treatment and prognosis of the patients. Results: PSCTC is most often seen in older men and progresses rapidly. In laboratory tests, some patients had elevated levels of tumor markers (CA199, squamous cell carcinoma antigen level), thyroglobulin levels and tumor-related substances, but all these indicators lacked specificity. The ultrasound features of PSCTC are mainly hypoechoic, hard, substantial nodules with gross borders and a grade 1-2 blood flow signal, sometimes with signs of necrosis and calcification. In terms of treatment, PSCTC is mainly surgically resected, though some patients in this study underwent iodine-131 radiation therapy, local radiotherapy, and chemotherapy with unclear results. None of the patients survived for very long after treatment, but the prognosis of patients with highly differentiated squamous carcinoma was significantly better than that of patients with poorly differentiated squamous carcinoma. Papillary thyroid carcinoma may be one of the causes of PSCTC. Conclusion: PSCTC is a malignant tumor with high malignancy and rapid clinical progression. Treatment options are mainly based on surgical resection and can be supplemented with radiotherapy and chemotherapy, but there is still a lack of a standardized treatment management system, and more cases and reports are needed to accumulate data.

11.
BMC Cancer ; 22(1): 776, 2022 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-35840910

RESUMEN

BACKGROUND: To investigate the differences in HPV genotypes and clinical indicators between cervical squamous cell carcinoma and adenocarcinoma and to identify independent predictors for differentiating cervical squamous cell carcinoma and adenocarcinoma. METHODS: A total of 319 patients with cervical cancer, including 238 patients with squamous cell carcinoma and 81 patients with adenocarcinoma, were retrospectively analysed. The clinical characteristics and laboratory indicators, including HPV genotypes, SCCAg, CA125, CA19-9, CYFRA 21-1 and parity, were analysed by univariate and multivariate analyses, and a classification model for cervical squamous cell carcinoma and adenocarcinoma was established. The model was validated in 96 patients with cervical cancer. RESULTS: There were significant differences in SCCAg, CA125, CA19-9, CYFRA 21-1, HPV genotypes and clinical symptoms between cervical squamous cell carcinoma and adenocarcinoma (P < 0.05). Logistic regression analysis showed that SCCAg and HPV genotypes (high risk) were independent predictors for differentiating cervical squamous cell carcinoma from adenocarcinoma. The AUC value of the established classification model was 0.854 (95% CI: 0.804-0.904). The accuracy, sensitivity and specificity of the model were 0.846, 0.691 and 0.899, respectively. The classification accuracy was 0.823 when the model was verified. CONCLUSION: The histological type of cervical cancer patients with persistent infection of high-risk HPV subtypes and low serum SCCAg levels was more prone to being adenocarcinoma. When the above independent predictors occur, the occurrence and development of cervical adenocarcinoma should be anticipated, and early active intervention treatment should be used to improve the prognosis and survival of patients.


Asunto(s)
Adenocarcinoma , Carcinoma de Células Escamosas , Papillomaviridae , Infecciones por Papillomavirus , Serpinas , Neoplasias del Cuello Uterino , Antígenos de Neoplasias , Antígeno CA-19-9 , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/virología , Femenino , Genotipo , Humanos , Queratina-19 , Papillomaviridae/genética , Infecciones por Papillomavirus/virología , Estudios Retrospectivos , Neoplasias del Cuello Uterino/patología , Neoplasias del Cuello Uterino/virología
12.
Bioorg Chem ; 125: 105867, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35576739

RESUMEN

Baeyer-Villiger monooxygenase (BVMO) mediated sulfoxidation is a sustainable approach for the synthesis of esomeprazole. In this work, a novel phenylacetone monooxygenase from Limnobacter sp. (LnPAMO) was found to have trace activity for synthesis of enantiopure esomeprazole. Through engineering in the substrate tunnel using a mutagenesis strategy called "nonpolarity paving" and some modifications in cofactor binding domains, a mutant harboring 15 mutations (LnPAMO Mu15) was obtained with 6.6 × 103-fold higher activity to convert omeprazole sulfide into esomeprazole. The activities of the mutant for synthesis of (S)-methyl phenyl sulfoxide and (S)-pantoprazole also increased much, indicating the versatility of the mutant for sulfoxide synthesis. Importantly, no over-oxidation byproduct omeprazole sulfone was detected in the sulfoxidation products by both mass spectrometry and HPLC analysis. Then NADP-dependent Burkholderia stabili formate dehydrogenase was ligated behind Mu15 along with a ribosome binding site sequence in pET-28a for co-expression. By single whole-cell of recombinant Escherichia coli BL21 coexpressing Mu15 and formate dehydrogenase, omeprazole sulfide was efficiently converted into esomeprazole without production of sulfone (16 g/L substrate, enantiomeric excess > 99.9% (S) and > 99% conversion) and the space-time-yield reached 1.67 g product/L/h.


Asunto(s)
Esomeprazol , Oxigenasas de Función Mixta , Acetona/análogos & derivados , Acetona/metabolismo , Escherichia coli/genética , Esomeprazol/metabolismo , Formiato Deshidrogenasas/metabolismo , Oxigenasas de Función Mixta/genética , Oxigenasas de Función Mixta/metabolismo , Oxidación-Reducción , Especificidad por Sustrato
13.
Front Microbiol ; 13: 869874, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35450283

RESUMEN

Diagnosis of botulism caused by multiple serotypes of botulinum neurotoxin (BoNT) is still a challenge due to the lack of a reliable detection method. The present study develops a feasible laboratorial method based on an isotope dilution Immuno-Endopep-MS to detect BoNTs and determine their serotypes and activities in clinical samples. Eleven positive foodborne botulism cases out of a total of 17 suspected cases in China, 2019-2022, were determined by the established method. Blood, urine, vomitus, gastric mucosa samples, and food samples were employed and evidenced to be suitable for the detection. Results showed that, although single type A-intoxication was still the first cause among these foodborne botulism cases, other causes involving type E, type B, and their mixed types were also determined, providing a glimpse to the serotype profile of botulism happened in recent years in China. Furthermore, in order to provide insights into in vivo profiles of toxin serotypes, a comprehensive analysis of clinical specimens collected from one family of four patients was performed during a clinically and therapeutically relevant time frame. Serotypes and concentrations of BoNT in specimens revealed a good correlation with symptoms and progresses of disease. Additionally, serum was proved to be more suitable for detection of BoNT/A with a detection window up to 12 days. A urine sample, although rarely reported for foodborne botulism diagnosis, was validated to be suitable for testing BoNTs, with a longer detection window up to 25 days. To the best of our knowledge, this is the first comprehensive analytical research on in vivo profiles of serotypes A, B, and E in different types of specimens from mixed botulism cases. Our method and findings facilitate the toxin detection and identification by clinical diagnostic laboratories.

14.
Polymers (Basel) ; 14(2)2022 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-35054651

RESUMEN

In this work, a flame retardant curing agent (DOPO-MAC) composed of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide DOPO and methyl acrylamide (MAC) was synthesized successfully, and the structure of the compound was characterized by FT-IR and 1H-NMR. The non-isothermal kinetics of the epoxy resin/DOPO-MAC system with 1% phosphorus was studied by non-isothermal DSC method. The activation energy of the reaction (Ea), about 46 kJ/mol, was calculated by Kissinger and Ozawa method, indicating that the curing reaction was easy to carry out. The flame retardancy of the epoxy resin system was analyzed by vertical combustion test (UL94) and limiting oxygen index (LOI) test. The results showed that epoxy resin (EP) with 1% phosphorus successfully passed a UL-94 V-0 rating, and the LOI value increased along with the increasing of phosphorus content. It confirmed that DOPO-MAC possessed excellent flame retardance and higher curing reactivity. Moreover, the thermal stability of EP materials was also investigated by TGA. With the DOPO-MAC added, the residual mass of EP materials increased remarkably although the initial decomposition temperature decreased slightly.

15.
J Fluoresc ; 32(2): 533-547, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34989924

RESUMEN

A drug delivery system with identification function is attractive and important. For this reason, the red fluorescence of Eu3+-doped ZnAl-LDH response to intercalation and release of ibuprofen (IBU) has been studied. X-ray diffraction(XRD) results showed that the basal spacing of the Eu3+-doped ZnAl-LDH varied from 8.85 to 12.04 Å after the intercalation of IBU. The release of the IBU from the Eu3+-doped ZnAl-LDH was carried out in simulated intestinal medium (phosphate buffer solutions with pH 7.4 and 37 °C), and the releasing behavior of IBU exhibited an initial rapid release followed by a slow release. Moreover, the present delivery system has slower release of drug than those of other LDH-based delivery systems. Interestingly, the intercalation of IBU into the Eu3+-doped ZnAl-LDH obviously reduced the red fluorescence of the Eu3+-doped ZnAl-LDH, whereas the red fluorescence was recovered after the release of IBU. This fluorescent responsiveness may be a favorable signal for detecting the delivery and release of IBU. Therefore, the Eu3+-doped ZnAl-LDH with red fluorescence would be potential application as drug delivery system with identification function because of its cheapness, non-toxicity, good biocompatibility, and little damage to biological tissue.


Asunto(s)
Sistemas de Liberación de Medicamentos/métodos , Europio/química , Ibuprofeno/química , Sustancias Intercalantes , Sustancias Luminiscentes/química , Aluminio/química , L-Lactato Deshidrogenasa/química , Análisis Espectral , Difracción de Rayos X , Zinc/química
16.
Front Immunol ; 12: 791220, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34917097

RESUMEN

T cell factor 1 (Tcf1) is known as a critical mediator for natural killer (NK) cell development and terminal maturation. However, its essential targets and precise mechanisms involved in early NK progenitors (NKP) are not well clarified. To investigate the role of Tcf1 in NK cells at distinct developmental phases, we employed three kinds of genetic mouse models, namely, Tcf7fl/flVavCre/+, Tcf7fl/flCD122Cre/+ and Tcf7fl/flNcr1Cre/+ mice, respectively. Similar to Tcf1 germline knockout mice, we found notably diminished cell number and defective development in BM NK cells from all strains. In contrast, Tcf7fl/flNcr1Cre/+ mice exhibited modest defects in splenic NK cells compared with those in the other two strains. By analyzing the published ATAC-seq and ChIP-seq data, we found that Tcf1 directly targeted 110 NK cell-related genes which displayed differential accessibility in the absence of Tcf1. Along with this clue, we further confirmed that a series of essential regulators were expressed aberrantly in distinct BM NK subsets with conditional ablating Tcf1 at NKP stage. Eomes, Ets1, Gata3, Ikzf1, Ikzf2, Nfil3, Runx3, Sh2d1a, Slamf6, Tbx21, Tox, and Zeb2 were downregulated, whereas Spi1 and Gzmb were upregulated in distinct NK subsets due to Tcf1 deficiency. The dysregulation of these genes jointly caused severe defects in NK cells lacking Tcf1. Thus, our study identified essential targets of Tcf1 in NK cells, providing new insights into Tcf1-dependent regulatory programs in step-wise governing NK cell development.


Asunto(s)
Factor Nuclear 1-alfa del Hepatocito/metabolismo , Células Asesinas Naturales/fisiología , Subgrupos Linfocitarios/fisiología , Células Progenitoras Linfoides/fisiología , Animales , Antígenos Ly/genética , Antígenos Ly/metabolismo , Diferenciación Celular , Células Cultivadas , Regulación de la Expresión Génica , Granzimas/genética , Granzimas/metabolismo , Factor Nuclear 1-alfa del Hepatocito/genética , Activación de Linfocitos , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Receptor 1 Gatillante de la Citotoxidad Natural/genética , Receptor 1 Gatillante de la Citotoxidad Natural/metabolismo , Proteínas de Dominio T Box/genética , Proteínas de Dominio T Box/metabolismo
17.
Arch Toxicol ; 95(11): 3559-3573, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34510228

RESUMEN

Amongst all toxicological endpoints, carcinogenicity might pose the greatest concern. Genetic damage has been considered an important underlying mechanism for the carcinogenicity of chemical substances. The demand for in vitro genotoxic tests as alternative approaches is growing rapidly with the implementation of new regulations for compounds. However, currently available in vitro genotoxicity tests are often limited by relatively high false positive rates. Moreover, few studies have explored carcinogenicity potential by in vitro genotoxicity testing due to the shortage of suitable toxicological biomarkers to link gene damage with cancer risk. γ-H2AX is a recently acknowledged attractive endpoint (biomarker) for evaluating DNA damage and can simultaneously reflect the DNA damage response and repair of cells. We previously reported an ultrasensitive and reliable method, namely stable-isotope dilution-liquid chromatography-tandem mass spectrometry (ID-LC-MS/MS), for detecting cellular γ-H2AX and evaluating genotoxic chemicals. More importantly, our method can dynamically monitor the specific processes of genotoxic compounds affecting DNA damage and repair reflected by the amount of γ-H2AX. To clarify the possibility of using this method to assess the potential carcinogenicity of genotoxic chemicals, we applied it to a set of 69 model compounds recommended by the European Center for the Validation of Alternative Methods (ECVAM), with already-characterized genotoxic potential. Compared to conventional in vitro genotoxicity assays, including the Ames test, the γ-H2AX assay by MS has high accuracy (94-96%) due to high sensitivity and specificity (88% and 100%, respectively). The dynamic profiles of model compounds after exposure in HepG2 cells were explored, and a mathematical approach was employed to simulate and quantitatively model the DNA repair kinetics of genotoxic carcinogens (GCs) based on γ-H2AX time-effect curves up to 8 h. Two crucial parameters, i.e., k (rate of γ-H2AX decay) and t50 (time required for γ-H2AX from maximum decrease to half) estimated by the least squares method, were achieved. An open web server to help researchers calculate these two key parameters and profile simulated curves of the tested compound is available online ( http://ccb1.bmi.ac.cn:81/shiny-server/sample-apps/prediction1/ ). We detected a positive association between carcinogenic levels and k and t50 values of γ-H2AX in tested GCs, validating the potential of using this MS-based γ-H2AX in vitro assay to help preliminarily evaluate carcinogenicity and assess genotoxicity. This approach may be used alone or integrated into an existing battery of in vitro genetic toxicity tests.


Asunto(s)
Pruebas de Carcinogenicidad/métodos , Histonas/análisis , Pruebas de Mutagenicidad/métodos , Biomarcadores/análisis , Cromatografía Liquida , Células Hep G2 , Ensayos Analíticos de Alto Rendimiento , Humanos , Técnicas In Vitro , Sensibilidad y Especificidad , Espectrometría de Masas en Tándem
18.
Braz J Med Biol Res ; 54(4): e10117, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33656053

RESUMEN

The long noncoding RNA (lncRNA) H19 is involved in the pathogenesis of endometriosis by modulating the proliferation and invasion of ectopic endometrial cells in vitro, but related in vivo studies are rare. This study aimed to investigate the role of lncRNA H19 in a nude mouse model of endometriosis. Ectopic endometrial stromal cells (ecESCs) were isolated from ectopic endometrium of patients with endometriosis and infected with lentiviruses expressing short hairpin RNA (shRNA) negative control (LV-NC-shRNA) or lncRNA-H19 shRNA (LV-H19-shRNA). The ecESCs infected with LV-NC-shRNA and LV-H19-shRNA were subcutaneously implanted into forty 6- to 8-week-old female nude mice. The size and weight of the endometriotic implants were measured at 1, 2, 3, and 4 weeks after implantation and compared, and lncRNA H19 levels in endometriotic implants were evaluated using real-time polymerase chain reaction (RT-PCR). All nude mice survived the experimental period, and no significant differences in body weight were observed between the experimental group and the control group. All nude mice developed histologically confirmed subcutaneous endometriotic lesions with glandular structures and stroma after 1 week of implantation. The subcutaneous lesions in the LV-NC-shRNA group after 1, 2, 3, and 4 weeks of implantation were larger than those in the LV-H19-shRNA group, and lncRNA H19 levels in subcutaneous lesions in the LV-NC-shRNA group were significantly higher than those in the LV-H19-shRNA group. Knockdown of lncRNA H19 suppresses endometriosis in vivo. Further study is required to explore the underlying mechanism in the future.


Asunto(s)
Endometriosis , ARN Largo no Codificante , Animales , Proliferación Celular/genética , Endometriosis/genética , Endometrio , Femenino , Humanos , Ratones , Ratones Desnudos , ARN Largo no Codificante/genética , ARN Interferente Pequeño/genética
19.
Braz. j. med. biol. res ; 54(4): e10117, 2021. tab, graf
Artículo en Inglés | LILACS | ID: biblio-1153531

RESUMEN

The long noncoding RNA (lncRNA) H19 is involved in the pathogenesis of endometriosis by modulating the proliferation and invasion of ectopic endometrial cells in vitro, but related in vivo studies are rare. This study aimed to investigate the role of lncRNA H19 in a nude mouse model of endometriosis. Ectopic endometrial stromal cells (ecESCs) were isolated from ectopic endometrium of patients with endometriosis and infected with lentiviruses expressing short hairpin RNA (shRNA) negative control (LV-NC-shRNA) or lncRNA-H19 shRNA (LV-H19-shRNA). The ecESCs infected with LV-NC-shRNA and LV-H19-shRNA were subcutaneously implanted into forty 6- to 8-week-old female nude mice. The size and weight of the endometriotic implants were measured at 1, 2, 3, and 4 weeks after implantation and compared, and lncRNA H19 levels in endometriotic implants were evaluated using real-time polymerase chain reaction (RT-PCR). All nude mice survived the experimental period, and no significant differences in body weight were observed between the experimental group and the control group. All nude mice developed histologically confirmed subcutaneous endometriotic lesions with glandular structures and stroma after 1 week of implantation. The subcutaneous lesions in the LV-NC-shRNA group after 1, 2, 3, and 4 weeks of implantation were larger than those in the LV-H19-shRNA group, and lncRNA H19 levels in subcutaneous lesions in the LV-NC-shRNA group were significantly higher than those in the LV-H19-shRNA group. Knockdown of lncRNA H19 suppresses endometriosis in vivo. Further study is required to explore the underlying mechanism in the future.


Asunto(s)
Humanos , Animales , Femenino , Conejos , Endometriosis/genética , ARN Largo no Codificante/genética , ARN Interferente Pequeño/genética , Proliferación Celular/genética , Endometrio , Ratones Desnudos
20.
Luminescence ; 35(7): 1125-1133, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32488962

RESUMEN

A series of Er3+ -doped magnesium aluminium layered double hydroxides (Er3+ -doped, MgAl-LDHs) with different Mg2+ /(Al3+ +Er3+ ) molar ratios were synthesized using the hydrothermal method. Compositional and structural analyses suggest that the Er3+ -doped MgAl-LDHs kept a hexagonal structure while the Mg2+ /(Al3+ +Er3+ ) molar ratio was at 1.0-4.1. The downconverted emission spectra of the Er3+ -doped MgAl-LDHs showed a red emission at 650 nm and strong infrared emissions at 720, 780, and 850 nm. These infrared emissions were hardly observed in previous downconverted emission spectra of Er3+ -doped materials. In the analysis of the Er3+ energy levels and in relevant published literature, the energy transfer diagram for Er3+ -doped in MgAl-LDHs is described, and infrared emissions at 720, 780, and 850 nm may be attributed to 4 F7/2 →4 I13/2 , 2 H11/2 →4 I13/2 , and 4 S3/2 →4 I13/2 transitions of Er3+ , respectively. Er3+ -doped MgAl-LDHs could have potential application as marking and targeting agents in the processes for drug delivery in consideration of the strong near-infrared Er3+ emissions, as well as the special layered structure of MgAl-LDH.


Asunto(s)
Aluminio , Hidróxidos , Transferencia de Energía , Magnesio
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