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1.
Nature ; 620(7972): 72-77, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37168015

RESUMEN

A recent study demonstrated near-ambient superconductivity in nitrogen-doped lutetium hydride1. This stimulated a worldwide interest in exploring room-temperature superconductivity at low pressures. Here, by using a high-pressure and high-temperature synthesis technique, we have obtained nitrogen-doped lutetium hydride (LuH2±xNy), which has a dark-blue colour and a structure with the space group [Formula: see text] as evidenced by X-ray diffraction. This structure is the same as that reported in ref. 1, with a slight difference in lattice constant. Raman spectroscopy of our samples also showed patterns similar to those observed in ref. 1. Energy-dispersive X-ray spectroscopy confirmed the presence of nitrogen in the samples. We observed a metallic behaviour from 350 K to 2 K at ambient pressure. On applying pressures from 2.1 GPa to 41 GPa, we observed a gradual colour change from dark blue to violet to pink-red. By measuring the resistance at pressures ranging from 0.4 GPa to 40.1 GPa, we observed a progressively improved metallic behaviour; however, superconductivity was not observed above 2 K. Temperature dependence of magnetization at high pressure shows a very weak positive signal between 100 K and 320 K, and the magnetization increases with an increase in magnetic field at 100 K. All of these are not expected for superconductivity above 100 K. Thus, we conclude the absence of near-ambient superconductivity in this nitrogen-doped lutetium hydride at pressures below 40.1 GPa.

2.
Proc Natl Acad Sci U S A ; 120(20): e2302407120, 2023 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-37155859

RESUMEN

Clarifying the reaction pathways at the solid-water interface and in bulk water solution is of great significance for the design of heterogeneous catalysts for selective oxidation of organic pollutants. However, achieving this goal is daunting because of the intricate interfacial reactions at the catalyst surface. Herein, we unravel the origin of the organic oxidation reactions with metal oxide catalysts, revealing that the radical-based advanced oxidation processes (AOPs) prevail in bulk water but not on the solid catalyst surfaces. We show that such differing reaction pathways widely exist in various chemical oxidation (e.g., high-valent Mn3+ and MnOX) and Fenton and Fenton-like catalytic oxidation (e.g., Fe2+ and FeOCl catalyzing H2O2, Co2+ and Co3O4 catalyzing persulfate) systems. Compared with the radical-based degradation and polymerization pathways of one-electron indirect AOP in homogeneous reactions, the heterogeneous catalysts provide unique surface properties to trigger surface-dependent coupling and polymerization pathways of a two-electron direct oxidative transfer process. These findings provide a fundamental understanding of catalytic organic oxidation processes at the solid-water interface, which could guide the design of heterogeneous nanocatalysts.

3.
Proc Natl Acad Sci U S A ; 120(24): e2219649120, 2023 06 13.
Artículo en Inglés | MEDLINE | ID: mdl-37276408

RESUMEN

How left-right (LR) asymmetry emerges in a patterning field along the anterior-posterior axis remains an unresolved problem in developmental biology. Left-biased Nodal emanating from the LR organizer propagates from posterior to anterior (PA) and establishes the LR pattern of the whole embryo. However, little is known about the regulatory mechanism of the PA spread of Nodal and its asymmetric activation in the forebrain. Here, we identify bilaterally expressed Follistatin (Fst) as a regulator blocking the propagation of the zebrafish Nodal ortholog Southpaw (Spaw) in the right lateral plate mesoderm (LPM), and restricting Spaw transmission in the left LPM to facilitate the establishment of a robust LR asymmetric Nodal patterning. In addition, Fst inhibits the Activin-Nodal signaling pathway in the forebrain thus preventing Nodal activation prior to the arrival, at a later time, of Spaw emanating from the left LPM. This contributes to the orderly propagation of asymmetric Nodal activation along the PA axis. The LR regulation function of Fst is further confirmed in chick and frog embryos. Overall, our results suggest that a robust LR patterning emerges by counteracting a Fst barrier formed along the PA axis.


Asunto(s)
Proteínas de Pez Cebra , Pez Cebra , Animales , Pez Cebra/genética , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Folistatina/genética , Folistatina/metabolismo , Tipificación del Cuerpo/genética , Factor de Crecimiento Transformador beta/metabolismo , Regulación del Desarrollo de la Expresión Génica
4.
PLoS Biol ; 20(11): e3001856, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36318514

RESUMEN

Feingold syndrome type 1, caused by loss-of-function of MYCN, is characterized by varied phenotypes including esophageal and duodenal atresia. However, no adequate model exists for studying the syndrome's pathological or molecular mechanisms, nor is there a treatment strategy. Here, we developed a zebrafish Feingold syndrome type 1 model with nonfunctional mycn, which had severe intestinal atresia. Single-cell RNA-seq identified a subcluster of intestinal cells that were highly sensitive to Mycn, and impaired cell proliferation decreased the overall number of intestinal cells in the mycn mutant fish. Bulk RNA-seq and metabolomic analysis showed that expression of ribosomal genes was down-regulated and that amino acid metabolism was abnormal. Northern blot and ribosomal profiling analysis showed abnormal rRNA processing and decreases in free 40S, 60S, and 80S ribosome particles, which led to impaired translation in the mutant. Besides, both Ribo-seq and western blot analysis showed that mTOR pathway was impaired in mycn mutant, and blocking mTOR pathway by rapamycin treatment can mimic the intestinal defect, and both L-leucine and Rheb, which can elevate translation via activating TOR pathway, could rescue the intestinal phenotype of mycn mutant. In summary, by this zebrafish Feingold syndrome type 1 model, we found that disturbance of ribosomal biogenesis and blockage of protein synthesis during development are primary causes of the intestinal defect in Feingold syndrome type 1. Importantly, our work suggests that leucine supplementation may be a feasible and easy treatment option for this disease.


Asunto(s)
Microcefalia , Pez Cebra , Animales , Proteína Proto-Oncogénica N-Myc , Pez Cebra/metabolismo , Microcefalia/genética , Serina-Treonina Quinasas TOR/metabolismo , Leucina
5.
Opt Lett ; 48(22): 5831-5834, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37966730

RESUMEN

We propose a scheme to realize a novel, to the best of our knowledge, scenario that the single-photon transport in a one-dimensional waveguide can be affected by the temperature. The scheme is composed by a waveguide-atom interacting structure linked to a thermal bath. The single-photon reflection (or transmission) coefficient can be controlled by adjusting the temperature of the thermal bath. This provides a thermal control of the single-photon transport. Moreover, the scheme provides an approach for implementing the optical thermometer, in which the temperature of the thermal bath is estimated by measuring the photonic transport. The thermometer can accurately measure the temperature in the low-temperature region.

6.
Opt Lett ; 48(3): 823-826, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36723598

RESUMEN

We investigate the heat conduction between two one-dimensional waveguides intermediated by a laser-driving atom. The laser provides the optical control of the heat conduction. The tunable asymmetric conduction of the heat against the temperature gradient is realized. Assisted by the modulated laser, the heat conduction from either waveguide to the other waveguide can be suppressed. The heat currents can be significantly amplified by the energy flow of the laser.

7.
Environ Sci Technol ; 57(26): 9744-9753, 2023 07 04.
Artículo en Inglés | MEDLINE | ID: mdl-37339114

RESUMEN

Phthalate monoesters (me-PAEs) have been used as biomarkers for assessing human exposure to phthalate esters (PAEs) for a long time, and studies on the sources and distribution of me-PAEs in the environment are limited. In this study, dust samples from microenvironments were collected to measure the occurrence of PAEs and me-PAEs, as well as the bacterial diversity. The results indicated that me-PAEs coexisted with PAEs in different microenvironmental dust samples, with concentrations of nine PAEs and 16 me-PAEs ranging from 108 to 1450 µg/g (median range) and 6.00 to 21.6 µg/g, respectively. The concentrations of several low molecular weight me-PAEs (e.g., monomethyl phthalate and monoethyl phthalate) in dust were even significantly higher than those of their parents. The bacteria in the dust were mainly predominant with Proteobacteria, Actinobacteria, Bacteroidetes, and Firmicutes (total abundance >90%). Bacteria from bus and air conditioning dust samples had the highest species richness and species diversity. Seven genes of suspected enzymes with the ability to degrade PAEs were selected, and the concentration of me-PAEs increased with increasing abundance of enzyme function. Our findings will provide useful information on the profiles of me-PAEs and their potential sources in indoor dusts, which will benefit the accurate estimation of human exposure.


Asunto(s)
Polvo , Ácidos Ftálicos , Humanos , Polvo/análisis , Ésteres/análisis , Ácidos Ftálicos/análisis , China
8.
Environ Res ; 227: 115739, 2023 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-36963715

RESUMEN

Bisphenol diglycidyl ethers (BDGEs) and Bisphenol A and its analogs (bisphenols) may have the same exposure routes and coexposure phenomenon in sensitive populations such as pregnant women. Previous biomonitoring studies on BDGEs are limited. Levels of fifteen bisphenols, six BDGEs and the DNA oxidative damage biomarker 8-hydroxy-2-deoxyguanosine (8-OHdG) were measured in the urine of pregnant women recruited in south China (n = 358). We aimed to provide the occurrence of bisphenols and BDGEs in pregnant women, and to investigate the potential relationship between their exposure and oxidative stress. Bisphenol A, bisphenol S, bisphenol F, bisphenol AP and all BDGEs (except for BADGE·2HCl) were frequently detected. The total concentrations of all bisphenols and BDGEs were 0.402-338 and 0.104-32.5 ng/mL, with geometric means of 2.87 and 2.48 ng/mL, respectively. BFDGE was the most abundant chemical of BDGEs, with a median concentration of 0.872 ng/mL, followed by BADGE·H2O·HCl (0.297 ng/mL). Except for pre-pregnancy obesity, maternal age/height, employment, fasting in the morning and parity did not affect the urinary concentrations of BDGEs. Significant and weak correlations were observed between concentrations (unadjusted) of total bisphenols and BDGEs (r = 0.389, p < 0.01), indicating their similar sources and exposure routes. The biomarker 8-OHdG was detected in all samples, with concentrations ranging from 1.98 to 32.6 ng/mL (median: 9.96 ng/mL). Levels of 8-OHdG were positively correlated with urinary several bisphenol concentrations (adjusted ß range: 0.037-0.089, p < 0.05) but were not correlated with those of BDGEs. Further studies should focus on whether BDGEs and bisphenols exert combined effects on oxidative stress. Our study provided the first BDGEs exposure data in pregnant women and indicated that BDGEs exposure was highly prevalent in pregnant women as early as 2015 in south China.


Asunto(s)
Compuestos de Bencidrilo , Mujeres Embarazadas , Humanos , Femenino , Embarazo , Compuestos de Bencidrilo/toxicidad , Compuestos Epoxi/toxicidad , Edad Materna , Paridad
9.
Yi Chuan ; 44(11): 1044-1055, 2022 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-36384996

RESUMEN

Mitogen-activated protein kinase kinase kinases (MAPKKKs) are important components of the MAPK cascade and play crucial roles in development and stress responses. Arabidopsis pumila is an ephemeral Brassicaceae plant growing in Xinjiang desert regions, which possesses salt tolerance. To explore the evolution and function of the MAPKKK gene family in A. pumila, 143 ApMAPKKK genes were identified from A. pumila genome by genome-wide analysis, which were categorized into three subfamilies: ZIK (20), MEKK (36) and RAF (87). There existed 74 and 72 colinear genes between A. thaliana, A. lyrata and A. pumila, respectively, indicating that this gene family expanded obviously in A. pumila genome. Evolutionary analysis revealed that there were 64 duplicated gene pairs with Ka/Ks less than 1, and purifying selection was dominant. RNA-seq data were used to analyze the expression characteristics of ApMAPKKK genes in response to salt stress and in different tissues. The results showed that most ApMAPKKK genes were up-regulated under 250 mmol/L NaCl stress. For example, ApMAPKKK18-1/2 and ApMAPKKK17-1/2 were substantially up-regulated. Tissue expression profiles showed that ApMAPKKK mainly presented six expression patterns. Some duplicated genes were differentially expressed in response to salt stress and in different tissues. These results lay a foundation for further understanding the complex mechanism of MAPKKK gene family transduction pathway in response to abiotic stresses in A. pumila.


Asunto(s)
Arabidopsis , Quinasas Quinasa Quinasa PAM , Filogenia , Quinasas Quinasa Quinasa PAM/genética , Quinasas Quinasa Quinasa PAM/metabolismo , Arabidopsis/genética , Arabidopsis/metabolismo , Familia de Multigenes , Perfilación de la Expresión Génica , Secuencia de Aminoácidos
10.
Environ Sci Technol ; 55(10): 7063-7071, 2021 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-33961405

RESUMEN

As one of the extensively used feed additives in livestock and poultry breeding, p-arsanilic acid (p-ASA) has become an organoarsenic pollutant with great concern. For the efficient removal of p-ASA from water, the combination of chemical oxidation and adsorption is recognized as a promising process. Herein, hollow/porous Mn-Fe-mixed oxide (MnFeO) nanocubes were synthesized and used in coupling with peroxymonosulfate (PMS) to oxidize p-ASA and remove the total arsenic (As). Under acidic conditions, both p-ASA and total As could be completely removed in the PMS/MnFeO process and the overall performance was substantially better than that of the Mn/Fe monometallic system. More importantly, an interface-promoted direct oxidation mechanism was found in the p-ASA-involved PMS/MnFeO system. Rather than activate PMS to generate reactive oxygen species (i.e., SO4·-, ·OH, and 1O2), the MnFeO nanocubes first adsorbed p-ASA to form a ligand-oxide interface, which improved the oxidation of the adsorbed p-ASA by PMS and ultimately enhanced the removal of the total As. Such a direct oxidation process achieved selective oxidation of p-ASA and avoidance of severe interference from the commonly present constituents in real water samples. After facile elution with dilute alkali solution, the used MnFeO nanocubes exhibited superior recyclability in the repeated p-ASA removal experiments. Therefore, this work provides a promising approach for efficient abatement of phenylarsenical-caused water pollution based on the PMS/MnFeO oxidation process.


Asunto(s)
Arsénico , Contaminantes Químicos del Agua , Ácido Arsanílico , Oxidación-Reducción , Óxidos , Peróxidos
11.
Angew Chem Int Ed Engl ; 60(1): 274-280, 2021 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-32965786

RESUMEN

Transition metal (TM)-based bimetallic spinel oxides can efficiently activate peroxymonosulfate (PMS) presumably attributed to enhanced electron transfer between TMs, but the existing model cannot fully explain the efficient TM redox cycling. Here, we discover a critical role of TM-O covalency in governing the intrinsic catalytic activity of Co3-x Mnx O4 spinel oxides. Experimental and theoretical analysis reveals that the Co sites significantly raises the Mn valence and enlarges Mn-O covalency in octahedral configuration, thereby lowering the charge transfer energy to favor MnOh -PMS interaction. With appropriate MnIV /MnIII ratio to balance PMS adsorption and MnIV reduction, the Co1.1 Mn1.9 O4 exhibits remarkable catalytic activities for PMS activation and pollutant degradation, outperforming all the reported TM spinel oxides. The improved understandings on the origins of spinel oxides activity for PMS activation may inspire the development of more active and robust metal oxide catalysts.

12.
Environ Sci Technol ; 58(26): 11205-11208, 2024 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-38904430
13.
J Asian Nat Prod Res ; 18(9): 908-12, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27268073

RESUMEN

A new diterpenoid alkaloid, named bullatine H (1), along with 10 known diterpenoid alkaloids were isolated from the roots of Aconitum brachypodum Diels (Ranunculaceae). The structure of 1 was elucidated by analysis of its spectroscopic data. It should be noted that compound 1 is the first example with 11, 13-dioxygenated denudatine-type diterpenoid alkaloid isolated from Aconitum brachypodum.


Asunto(s)
Aconitum/química , Alcaloides/aislamiento & purificación , Diterpenos/aislamiento & purificación , Medicamentos Herbarios Chinos/aislamiento & purificación , Raíces de Plantas/química , Alcaloides/química , Diterpenos/química , Medicamentos Herbarios Chinos/química , Estructura Molecular , Resonancia Magnética Nuclear Biomolecular
14.
Mol Reprod Dev ; 82(2): 132-8, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25651825

RESUMEN

Litter size is a favorable economic trait for the goat industry, but remains a complex trait controlled by multiple genes in multiple organs. Several genes have been identified that may affect embryo survival, follicular development, and the health of fetuses during pregnancy. Jining Grey goats demonstrate the largest litter size among goat breeds indigenous to China. In order to better understand the genetic basis of this trait, six suppression subtractive hybridization (SSH) cDNA libraries were constructed using pooled mRNAs from hypothalamuses, pituitaries, and ovaries of sexually mature and adult polytocous Jining Grey goats, as testers, versus the pooled corresponding mRNAs of monotocous Liaoning Cashmere goats, as drivers. A total of 1,458 true-positive clones--including 955 known genes and 481 known and 22 unknown expressed sequence tags--were obtained from the SSH libraries by sequencing and alignment. The known genes were categorized into cellular processes and signaling information storage and processing, and metabolism. Three genes (FTH1, GH, and SAA) were selected to validate the SSH results by quantitative real-time PCR; all three were up-regulated in the corresponding tissues in the tester group indicating that these are candidate genes associated with the large litter size of Jining Grey goats. Several other identified genes may affect embryo survival, follicular development, and health during pregnancy. This study provides insights into the mechanistic basis by which the caprine hypothalamic-pituitary-gonadal axis affects reproductive traits and provides a theoretical basis for goat production and breeding.


Asunto(s)
Regulación del Desarrollo de la Expresión Génica/genética , Cabras/genética , Gónadas/metabolismo , Sistema Hipotálamo-Hipofisario/metabolismo , Tamaño de la Camada/genética , Herencia Multifactorial/genética , Animales , Secuencia de Bases , Cruzamiento/métodos , China , Cartilla de ADN/genética , Femenino , Biblioteca de Genes , Cabras/metabolismo , Datos de Secuencia Molecular , Embarazo , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ADN/veterinaria , Técnicas de Hibridación Sustractiva/veterinaria
15.
Acta Cardiol ; 70(1): 67-72, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26137805

RESUMEN

The angiotensin II type 1 receptor (AT1R) antagonist protects the heart against acute ischaemia-reperfusion injury. The underlying mechanism is unclear. To determine the effects of angiotensin II type 1 receptor blockade, valsartan on AT1 and AT2 receptor during ischaemia reperfusion in isolated rat, the hearts of 24 SD rats were isolated, linked to Langendorff perfusion apparatus, and exposed to ischaemia for 30 min.The left ventricular systolic pressure, maximal uprising velocity of left ventricular pressure (+dp/dt(max)), maximal decreasing velocity of left ventricular pressure (-dp/dt(max)) and coronary flow were measured after stabilization of the perfusion.The isoenzyme of creatine kinase in the effluent liquid from the heart, AT1 and AT2 receptor mRNA and protein expression were measured after stabilization of the perfusion. The results showed that ischaemia-reperfusion induced a marked decrease in left ventricular systolic pressure, +dp/dt(max) and -dp/dt(max) indicating severe cardiac dysfunction and decreased coronary effluence. Concurrently, myocardial AT1 and AT2 receptor mRNA and protein expression were increased with valsartan. However, AT2 receptor mRNA and protein expression decreased during ischaemia-reperfusion. The creatine kinase levels at different time points of the valsartan group were significantly lower. The results suggested that valsartan improved left ventricular function and increased coronary effluence because the angiotensin receptor blocker valsartan induced cardioprotection associated with upregulating AT2 receptor protein and mRNA expression after ischaemia-reperfusion in isolated rats.


Asunto(s)
Regulación de la Expresión Génica , Daño por Reperfusión Miocárdica/genética , ARN Mensajero/genética , Receptor de Angiotensina Tipo 2/genética , Tetrazoles/farmacología , Regulación hacia Arriba/efectos de los fármacos , Valina/análogos & derivados , Bloqueadores del Receptor Tipo 1 de Angiotensina II/farmacología , Animales , Western Blotting , Circulación Coronaria/efectos de los fármacos , Modelos Animales de Enfermedad , Masculino , Daño por Reperfusión Miocárdica/tratamiento farmacológico , Daño por Reperfusión Miocárdica/metabolismo , Ratas , Ratas Sprague-Dawley , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptor de Angiotensina Tipo 2/biosíntesis , Valina/farmacología , Valsartán
16.
Yao Xue Xue Bao ; 50(6): 650-7, 2015 Jun.
Artículo en Zh | MEDLINE | ID: mdl-26521433

RESUMEN

Platinum-based anticancer drugs have been becoming one of the most effective drugs for clinical treatment of malignant tumors for its unique mechanism of action and broad range of anticancer spectrum. But, there are still several problems such as side effects, drug resistance/cross resistance and no-specific targeting, becoming obstacles to restrict its expanding of clinical application. In recent years, supramolecular chemistry drug delivery systems have been gradually concerned for their favorable safety and low toxicity. Supramolecular macrocycles-platinum complexes increased the water solubility, stability and safety of traditional platinum drugs, and have become hot focus of developing novel platinum-based anticancer drugs because of its potential targeting of tumor tissues/organs. This article concentrates in the research progress of the new drug delivery system between platinum-based anticancer drugs with three generations of macrocycles: crown ether, cyclodextrin, cucurbituril and calixarene.


Asunto(s)
Antineoplásicos/farmacología , Sistemas de Liberación de Medicamentos , Compuestos Macrocíclicos/farmacología , Compuestos de Platino/farmacología , Calixarenos , Compuestos Corona , Ciclodextrinas , Humanos , Neoplasias/tratamiento farmacológico
17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 37(5): 596-601, 2015 Oct.
Artículo en Zh | MEDLINE | ID: mdl-26564514

RESUMEN

OBJECTIVE: To evaluate the role of low-dose radioiodine in the treatment of non-metastatic high-risk differentiated thyroid cancer (DTC) patients with macroscopic extra-thyroidal extension (MAEE). METHODS: Totally 103 DTC patients with total/near-total thyroidectomy and selective lymph node resection, and with MAEE, any N stage,preablative stimulated thyroglobulin (ps-Tg) ≤ 5 ng/ml when thyroglobulin antibodies (TgAb) ≤ 46 U/ml and no evidence of distant metastasis were retrospectively analyzed in this study. Fifty-two received low dose RAI (1110 MBq) and 51 received high dose (≥ 3700 MBq). The successful ablation rate and disease-free survival rate were compared between these two groups. RESULTS: The successful ablative rate was 86.5% (45/52) in low-dose group and 86.3% (44/51) in high-dose group (P=0.9688), and the disease-free survival was 97.4% (38/39) in low-dose group and 97.5% (39/40) in high-dose group. CONCLUSION: The ablation success and medium-term clinical outcome with low-dose RAI is proved to be non-inferior to high dose in non-metastatic patients with MAEE when ps-Tg level is less than 5 ng/ml.


Asunto(s)
Neoplasias de la Tiroides , Autoanticuerpos , Supervivencia sin Enfermedad , Humanos , Radioisótopos de Yodo , Estudios Retrospectivos , Tiroglobulina , Tiroidectomía
18.
Stem Cell Res ; 76: 103328, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38335661

RESUMEN

Fibroblasts were extracted from the scalp of a healthy 55-year-old male and subsequently transformed into pluripotent stem cells by introducing episomal plasmids harboring essential reprogramming factors. These induced pluripotent stem cells exhibited a normal karyotype and demonstrated the capacity to differentiate into all three germ layers, as confirmed through teratoma assays. This specific cell line serves as a valuable reference for comparative investigations alongside other induced pluripotent stem cell lines generated from somatic cells of patients afflicted by genetic neurodegenerative disorders.


Asunto(s)
Células Madre Pluripotentes Inducidas , Teratoma , Humanos , Masculino , Persona de Mediana Edad , Diferenciación Celular , Línea Celular , Reprogramación Celular , Fibroblastos/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Plásmidos , Teratoma/metabolismo
19.
World J Gastrointest Oncol ; 16(3): 670-686, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38577437

RESUMEN

BACKGROUND: The incidence and mortality of colorectal cancer (CRC) are among the highest in the world, and its occurrence and development are closely related to tumor neovascularization. When the balance between pigment epithelium-derived factors (PEDF) that inhibit angiogenesis and vascular endothelial growth factors (VEGF) that stimulate angiogenesis is broken, angiogenesis is out of control, resulting in tumor development. Therefore, it is very necessary to find more therapeutic targets for CRC for early intervention and later treatment. AIM: To investigate the expression and significance of PEDF, VEGF, and CD31-stained microvessel density values (CD31-MVD) in normal colorectal mucosa, adenoma, and CRC. METHODS: In this case-control study, we collected archived wax blocks of specimens from the Digestive Endoscopy Center and the General Surgery Department of Chengdu Second People's Hospital from April 2022 to October 2022. Fifty cases of specimen wax blocks were selected as normal intestinal mucosa confirmed by electronic colonoscopy and concurrent biopsy (normal control group), 50 cases of specimen wax blocks were selected as colorectal adenoma confirmed by electronic colonoscopy and pathological biopsy (adenoma group), and 50 cases of specimen wax blocks were selected as CRC confirmed by postoperative pathological biopsy after inpatient operation of general surgery (CRC group). An immunohistochemical staining experiment was carried out to detect PEDF and VEGF expression in three groups of specimens, analyze their differences, study the relationship between the two and clinicopathological factors in CRC group, record CD31-MVD in the three groups, and analyze the correlation of PEDF, VEGF, and CD31-MVD in the colorectal adenoma group and the CRC group. The F test or adjusted F test is used to analyze measurement data statistically. Kruskal-Wallis rank sum test was used between groups for ranked data. The chi-square test, adjusted chi-square test, or Fisher's exact test were used to compare the rates between groups. All differences between groups were compared using the Bonferroni method for multiple comparisons. Spearman correlation analysis was used to test the correlation of the data. The test level (α) was 0.05, and a two-sided P< 0.05 was considered statistically significant. RESULTS: The positive expression rate and expression intensity of PEDF were gradually decreased in the normal control group, adenoma group, and CRC group (100% vs 78% vs 50%, χ2 = 34.430, P < 0.001; ++~++ vs +~++ vs -~+, H = 94.059, P < 0.001), while VEGF increased gradually (0% vs 68% vs 96%, χ2 = 98.35, P < 0.001; - vs -~+ vs ++~+++, H = 107.734, P < 0.001). In the CRC group, the positive expression rate of PEDF decreased with the increase of differentiation degree, invasion depth, lymph node metastasis, distant metastasis, and TNM stage (χ2 = 20.513, 4.160, 5.128, 6.349, 5.128, P < 0.05); the high expression rate of VEGF was the opposite (χ2 = 10.317, 13.134, 17.643, 21.844, 17.643, P < 0.05). In the colorectal adenoma group, the expression intensity of PEDF correlated negatively with CD31-MVD (r = -0.601, P < 0.001), whereas VEGF was not significantly different (r = 0.258, P = 0.07). In the CRC group, the expression intensity of PEDF correlated negatively with the expression intensity of CD31-MVD and VEGF (r = -0.297, P < 0.05; r = -0.548, P < 0.05), while VEGF expression intensity was positively related to CD31-MVD (r = 0.421, P = 0.002). CONCLUSION: It is possible that PEDF can be used as a new treatment and prevention target for CRC by upregulating the expression of PEDF while inhibiting the expression of VEGF.

20.
World J Gastrointest Oncol ; 16(3): 750-760, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38577441

RESUMEN

BACKGROUND: Lipid metabolism reprogramming is suspected to exist in pre-cancerous lesions, including colorectal adenoma. Screening colonoscopy frequently reveals chicken skin mucosa (CSM; white or yellow-white speckled mucosa) surrounding colorectal polyps, caused by macrophages engulfing and accumulating the lipids decomposed by colon cells or adjacent tumors. CSM-positive colorectal polyps are associated with various diseases; however, their prognosis varies greatly. Cold snare polypectomy is commonly used to resect lesions up to 10 to 15 mm in diameter without signs of submucosal invasion but is controversial for CSM-positive colorectal polyps. Improved imaging is required to diagnose and treat CSM-positive colorectal polyps. AIM: To highlight the clinical significance of CSM surrounding colorectal polyps and clarify the associated treatment for endoscopists. METHODS: This retrospective cohort study included 177 patients with CSM-positive colorectal polyps diagnosed using endoscopy. All patient-related information was extracted from the Goldisc soft-clinic DICOM system or electronic medical record system. Based on the pathological results, patients were classified as non-neoplastic polyps (five juvenile polyps), neoplastic polyps, non-invasive high-grade neoplasia (NHGN), or submucosal invasive carcinoma (SM stage cancer). We analyzed and compared the clinical features, suspected risk factors for malignant transformation of neoplastic polyps, and early infiltration of submucosal carcinoma. RESULTS: The diameters of NHGN and SM polyps were much smaller than those of neoplastic polyps. Most NHGN polyps had a deeper red mucosal color. On logistic regression analyses, diameter and deeper red mucosal color were independent risk factors for malignant transformation of neoplastic polyps. Type 1 CSM was more common in high-grade intraepithelial neoplasia and SM; type 2 CSM was more common in neoplastic polyps. Logistic regression analyses revealed no significant differences in the malignant transformation of neoplastic polyps or early submucosal invasion of CSM-positive colorectal cancer. Changes in the CSM mucosa surrounding neoplastic polyps and submucosal invasion of colorectal cancer disappeared within 12 months. No tumor recurrence was found during either partial or complete endoscopic resection of the CSM. CONCLUSION: CSM-positive colorectal polyps > 1 cm in diameter or with deeper red mucosa may be related to NHGN. Resection of CSM surrounding colorectal adenomas did not affect tumor recurrence.

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