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1.
Nano Lett ; 24(7): 2408-2414, 2024 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-38329291

RESUMEN

Two-dimensional (2D) heterostructures with ferromagnetism and ferroelectricity provide a promising avenue to miniaturize the device size, increase computational power, and reduce energy consumption. However, the direct synthesis of such eye-catching heterostructures has yet to be realized up to now. Here, we design a two-step chemical vapor deposition strategy to growth of Cr2S3/WS2 vertical heterostructures with atomically sharp and clean interfaces on sapphire. The interlayer charge transfer and periodic moiré superlattice result in the emergence of room-temperature ferroelectricity in atomically thin Cr2S3/WS2 vertical heterostructures. In parallel, long-range ferromagnetic order is discovered in 2D Cr2S3 via the magneto-optical Kerr effect technique with the Curie temperature approaching 170 K. The charge distribution variation induced by the moiré superlattice changes the ferromagnetic coupling strength and enhances the Curie temperature. The coexistence of ferroelectricity and ferromagnetism in 2D Cr2S3/WS2 vertical heterostructures provides a cornerstone for the further design of logic-in-memory devices to build new computing architectures.

2.
Plant J ; 114(3): 463-481, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36880270

RESUMEN

Plant responses to environmental change are mediated via changes in cellular metabolomes. However, <5% of signals obtained from liquid chromatography tandem mass spectrometry (LC-MS/MS) can be identified, limiting our understanding of how metabolomes change under biotic/abiotic stress. To address this challenge, we performed untargeted LC-MS/MS of leaves, roots, and other organs of Brachypodium distachyon (Poaceae) under 17 organ-condition combinations, including copper deficiency, heat stress, low phosphate, and arbuscular mycorrhizal symbiosis. We found that both leaf and root metabolomes were significantly affected by the growth medium. Leaf metabolomes were more diverse than root metabolomes, but the latter were more specialized and more responsive to environmental change. We found that 1 week of copper deficiency shielded the root, but not the leaf metabolome, from perturbation due to heat stress. Machine learning (ML)-based analysis annotated approximately 81% of the fragmented peaks versus approximately 6% using spectral matches alone. We performed one of the most extensive validations of ML-based peak annotations in plants using thousands of authentic standards, and analyzed approximately 37% of the annotated peaks based on these assessments. Analyzing responsiveness of each predicted metabolite class to environmental change revealed significant perturbations of glycerophospholipids, sphingolipids, and flavonoids. Co-accumulation analysis further identified condition-specific biomarkers. To make these results accessible, we developed a visualization platform on the Bio-Analytic Resource for Plant Biology website (https://bar.utoronto.ca/efp_brachypodium_metabolites/cgi-bin/efpWeb.cgi), where perturbed metabolite classes can be readily visualized. Overall, our study illustrates how emerging chemoinformatic methods can be applied to reveal novel insights into the dynamic plant metabolome and stress adaptation.


Asunto(s)
Brachypodium , Brachypodium/metabolismo , Cromatografía Liquida , Teoría de la Información , Cobre/metabolismo , Espectrometría de Masas en Tándem , Metabolómica/métodos , Metaboloma
3.
Small ; 20(3): e2305100, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37688343

RESUMEN

Diabetic chronic wounds pose significant clinical challenges due to their characteristic features of impaired extracellular matrix (ECM) function, diminished angiogenesis, chronic inflammation, and increased susceptibility to infection. To tackle these challenges and provide a comprehensive therapeutic approach for diabetic wounds, the first coaxial electrospun nanocomposite membrane is developed that incorporates multifunctional copper peroxide nanoparticles (n-CuO2 ). The membrane's nanofiber possesses a unique "core/sheath" structure consisting of n-CuO2 +PVP (Polyvinylpyrrolidone)/PCL (Polycaprolactone) composite sheath and a PCL core. When exposed to the wound's moist environment, PVP within the sheath gradually disintegrates, releasing the embedded n-CuO2 . Under a weakly acidic microenvironment (typically diabetic and infected wounds), n-CuO2 decomposes to release H2 O2 and Cu2+ ions and subsequently produce ·OH through chemodynamic reactions. This enables the anti-bacterial activity mediated by reactive oxygen species (ROS), suppressing the inflammation while enhancing angiogenesis. At the same time, the dissolution of PVP unveils unique nano-grooved surface patterns on the nanofibers, providing desirable cell-guiding function required for accelerated skin regeneration. Through meticulous material selection and design, this study pioneers the development of functional nanocomposites for multi-modal wound therapy, which holds great promise in guiding the path to healing for diabetic wounds.


Asunto(s)
Diabetes Mellitus , Nanocompuestos , Nanofibras , Humanos , Cicatrización de Heridas , Piel/lesiones , Nanocompuestos/química , Nanofibras/química , Inflamación
4.
Small ; 20(10): e2306508, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37919860

RESUMEN

The design and fabrication of NO-evolving core-shell nanoparticles (denoted as NC@Fe), comprised of BNN6-laden COF@Fe3 O4 nanoparticles, are reported. This innovation extends to the modification of 3D printed polyetheretherketone scaffolds with NC@Fe, establishing a pioneering approach to multi-modal bone therapy tailored to address complications such as device-associated infections and osteomyelitis. This work stands out prominently from previous research, particularly those relying on the use of antibiotics, by introducing a bone implant capable of simultaneous NO gas therapy and photothermal therapy (PPT). Under NIR laser irradiation, the Fe3 O4 NP core (photothermal conversion agent) within NC@Fe absorbs photoenergy and initiates electron transfer to the loaded NO donor (BNN6), resulting in controlled NO release. The additional heat generated through photothermal conversion further propels the NC@Fe nanoparticles, amplifying the therapeutic reach. The combined effect of NO release and PPT enhances the efficacy in eradicating bacteria over a more extensive area around the implant, presenting a distinctive solution to conventional challenges. Thorough in vitro and in vivo investigations validate the robust potential of the scaffold in infection control, osteogenesis, and angiogenesis, emphasizing the timeliness of this unique solution in managing complicated bone related infectious diseases.


Asunto(s)
Estructuras Metalorgánicas , Polímeros , Benzofenonas , Polietilenglicoles , Cetonas
5.
J Hum Genet ; 69(1): 3-11, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37821671

RESUMEN

Complex chromosomal rearrangements (CCRs) can result in spontaneous abortions, infertility, and malformations in newborns. In this study, we explored a familial CCR involving chromosome 6 by combining optical genomic mapping (OGM) and molecular cytogenetic methodologies. Within this family, the father and the paternal grandfather were both asymptomatic carriers of an identical balanced CCR, while the two offspring with an unbalanced paternal-origin CCR and two microdeletions presented with clinical manifestation. The first affected child, a 5-year-old boy, exhibited neurodevelopmental delay, while the second, a fetus, presented with hydrops fetalis. SNP-genotype analysis revealed a recombination event during gamete formation in the father that may have contributed to the deletion in his offspring. Meanwhile, the couple's haplotypes will facilitate the selection of normal gametes in the setting of assisted reproduction. Our study demonstrated the potential of OGM in identifying CCRs and its ability to work with current methodologies to refine precise breakpoints and construct accurate haplotypes for couples with a CCR.


Asunto(s)
Cromosomas Humanos Par 6 , Translocación Genética , Preescolar , Femenino , Humanos , Recién Nacido , Masculino , Embarazo , Aberraciones Cromosómicas , Cromosomas Humanos Par 6/genética , Análisis Citogenético , Genómica
6.
BMC Musculoskelet Disord ; 25(1): 290, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38622692

RESUMEN

BACKGROUND: The proximal femoral nail anti-rotation (PFNA) with cement enhancement enhances the anchorage ability of internal fixation in elderly with osteoporotic intertrochanteric fracture. However, whether it is superior to hemiarthroplasty is still controversial. The present study aimed to determine which treatment has better clinical outcomes among older patients. METHODS: We retrospectively analyzed 102 elderly patients with osteoporosis who developed intertrochanteric fractures and underwent PFNA combined with cement-enhanced internal fixation (n = 52, CE group), and hemiarthroplasty (n = 50, HA group) from September 2012 to October 2018. All the intertrochanteric fractures were classified according to the AO/OTA classification. Additionally, the operative time, intraoperative blood loss, intraoperative and postoperative blood transfusion rates, postoperative weight-bearing time, hospitalization time, Barthel Index of Activities Daily Living, Harris score of hip function, visual analog (VAS) pain score, and postoperative complications were compared between the two groups. RESULTS: The CE group had significantly shorter operative time, lesser intraoperative blood loss, lower blood transfusion rate, and longer postoperative weight-bearing time than the HA group. The CE group had lower Barthel's Index of Activities of Daily Living, lower Harris' score, and higher VAS scores in the first and third months after surgery than the HA group, but no difference was observed between the two groups from 6 months to 12 months. There was no significant difference in the total post-operative complications between the two groups. CONCLUSION: The use of PFNA combined with a cement-enhanced internal fixation technique led to shorter operative time and lesser intraoperative blood loss and trauma in elderly patients as compared to HA.


Asunto(s)
Fijación Intramedular de Fracturas , Hemiartroplastia , Fracturas de Cadera , Humanos , Anciano , Estudios Retrospectivos , Clavos Ortopédicos , Hemiartroplastia/efectos adversos , Hemiartroplastia/métodos , Pérdida de Sangre Quirúrgica/prevención & control , Actividades Cotidianas , Resultado del Tratamiento , Fracturas de Cadera/diagnóstico por imagen , Fracturas de Cadera/cirugía , Cementos para Huesos/uso terapéutico , Complicaciones Posoperatorias/cirugía , Fijación Intramedular de Fracturas/efectos adversos
7.
Int J Mol Sci ; 25(5)2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38473942

RESUMEN

Plant architecture is one of the key factors affecting maize yield formation and can be divided into secondary traits, such as plant height (PH), ear height (EH), and leaf number (LN). It is a viable approach for exploiting genetic resources to improve plant density. In this study, one natural panel of 226 inbred lines and 150 family lines derived from the offspring of T32 crossed with Qi319 were genotyped by using the MaizeSNP50 chip and the genotyping by sequence (GBS) method and phenotyped under three different environments. Based on the results, a genome-wide association study (GWAS) and linkage mapping were analyzed by using the MLM and ICIM models, respectively. The results showed that 120 QTNs (quantitative trait nucleotides) and 32 QTL (quantitative trait loci) related to plant architecture were identified, including four QTL and 40 QTNs of PH, eight QTL and 41 QTNs of EH, and 20 QTL and 39 QTNs of LN. One dominant QTL, qLN7-2, was identified in the Zhangye environment. Six QTNs were commonly identified to be related to PH, EH, and LN in different environments. The candidate gene analysis revealed that Zm00001d021574 was involved in regulating plant architecture traits through the autophagy pathway, and Zm00001d044730 was predicted to interact with the male sterility-related gene ms26. These results provide abundant genetic resources for improving maize plant architecture traits by using approaches to biological breeding.


Asunto(s)
Estudio de Asociación del Genoma Completo , Zea mays , Zea mays/genética , Fitomejoramiento , Mapeo Cromosómico , Fenotipo , Perfilación de la Expresión Génica , Ligamiento Genético
8.
Small ; 19(38): e2302029, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37194986

RESUMEN

Sodium-ion batteries (SIBs) have received increasing attention because of their appealing cell voltages and cost-effective features. However, the atom aggregation and electrode volume variation inevitably deteriorate the sodium storage kinetics. Here a new strategy is proposed to boost the lifetime of SIB by synthesizing sea urchin-like FeSe2 /nitrogen-doped carbon (FeSe2 /NC) composites. The robust FeN coordination hinders the Fe atom aggregation and accommodates the volume expansion, while the unique biomorphic morphology and high conductivity of FeSe2 /NC enhance the intercalation/deintercalation kinetics and shorten the ion/electron diffusion length. As expected, FeSe2 /NC electrodes deliver excellent half (387.6 mAh g-1 at 20.0 A g-1 after 56 000 cycles) and full (203.5 mAh g-1 at 1.0 A g-1 after 1200 cycles) cell performances. Impressively, an ultralong lifetime of SIB composed of FeSe2 /Fe3 Se4 /NC anode is uncovered with the cycle number exceeding 65 000. The sodium storage mechanism is clarified with the aid of density function theory calculations and in situ characterizations. This work hereby provides a new paradigm for enhancing the lifetime of SIB by constructing a unique coordination environment between active material and framework.

9.
Bioconjug Chem ; 2023 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-36961940

RESUMEN

Inspired by the negative Poisson's ratio (NPR) effects of the annulus fibrosus (AF) in intervertebral discs (IVDs), we designed a re-entrant honeycomb model and then 3D printed it into a poly(ε-caprolactone) (PCL) scaffold with NPR effects, which was followed by in situ polymerization of polypyrrole (PPy), thus constructing a PPy-coated NPR-structured PCL scaffold (-vPCL-PPy) to be used as the AF implant for the treatment of lumbar herniated discs. Mechanical testing and finite element (FE) simulation indicated that the NPR composite implant could sustain axial spine loading and resist nucleus pulposus (NP) swelling while displaying uniform stress diffusion under NP swelling and contraction. More interestingly, the NPR-structured composite scaffold could also apply a reacting force to restrain NP herniation owing to the NPR effect. In addition, the in vitro biological assessment and in vivo implantation demonstrated that the NPR composite scaffold exhibited good biocompatibility and exerted the ability to restore the physiological function of the disc segments.

10.
J Environ Manage ; 346: 119051, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37742564

RESUMEN

China's agriculture is in the transformation and development stage to adapt to the influences of climate change, technological progress and the requirements for resources and environmental protection. Optimization of cropping structure variation in the new stage is urgent. Our study systematically described the spatiotemporal variation in crop patterns in China from 1985 to 2015 and further analyzed the changes in cropping diversity and dominant cropping structure based on a county-level agricultural database. The results showed that the planted areas of staple crops and oil crops had expanded in three major grain-producing areas. Coarse crop planting has been gradually replaced by staple and oil crops. A slight increasing trend occurred in tuber crop planting in southwestern China, and fiber crop planting had already transferred from eastern to northwestern China. Moreover, cropping diversity has decreased in northern China, especially in the Northeast China Plain and North China Plain, while a slight increase has occurred in the south. Cropping structure has been simplified in past decades and it basically formed a single cropping structure dominated by staple or oil crops. Further cropping structure adjustments should focus on resource-saving, ecofriendly, intensive and efficient industrial coordination goals, adapting to the mechanization, scale and precision developments of agricultural production. It is important to develop a multifunctional innovative farming system and technology to ensure national food security.

11.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 40(12): 1461-1465, 2023 Dec 10.
Artículo en Zh | MEDLINE | ID: mdl-37994124

RESUMEN

OBJECTIVE: To carry out genetic analysis for a fetus with confined placental mosaicism (CPM) for trisomy 2 (T2) in conjunct with fetal uniparental disomy (UPD). METHODS: Amniocentesis and chromosomal karyotyping was carried out for a pregnant woman with a high risk for chromosome 2 anomalies indicated by non-invasive prenatal testing (NIPT). Single nucleotide polymorphism array (SNP-array) and trio-whole exome sequencing (Trio-WES) were carried out. Ultrasonography was used to closely monitor the fetal growth. Multifocal sampling of the placenta was performed after delivery for copy number variation sequencing (CNV-seq). RESULTS: The fetus was found to have a normal chromosomal karyotype. SNP-array has revealed multiple regions with loss of heterozygosity (LOH) on chromosome 2. Trio-WES confirmed the presence of maternal UPD for chromosome 2. Ultrasonography has revealed intrauterine growth restriction and oligohydramnios. Intrauterine fetal demise had occurred at 23+4 weeks of gestation. Pathological examination had failed to find salient visceral abnormality. The placenta was proved to contain complete T2 by CNV-seq. CONCLUSION: T2 CPM can cause false positive result for NIPT and may be complicated with fetal UPD, leading to adverse obstetric outcomes such as intrauterine growth restriction, oligohydramnios and intrauterine fetal demise.


Asunto(s)
Oligohidramnios , Placenta , Femenino , Humanos , Embarazo , Amniocentesis , Cromosomas Humanos Par 2/genética , Variaciones en el Número de Copia de ADN , Muerte Fetal , Retardo del Crecimiento Fetal/genética , Feto , Mosaicismo , Trisomía/genética , Disomía Uniparental/genética
12.
J Transl Med ; 20(1): 10, 2022 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-34980134

RESUMEN

BACKGROUND: Birth defects are responsible for approximately 7% of neonatal deaths worldwide by World Health Organization in 2004. Many methods have been utilized for examining the congenital anomalies in fetuses. This study aims to investigate the efficiency of simultaneous CNV-seq and whole-exome sequencing (WES) in the diagnosis of fetal anomaly based on a large Chinese cohort. METHODS: In this cohort study, 1800 pregnant women with singleton fetus in Hubei Province were recruited from 2018 to 2020 for prenatal ultrasonic screening. Those with fetal structural anomalies were transferred to the Maternal and Child Health Hospital of Hubei Province through a referral network in Hubei, China. After multidisciplinary consultation and decision on fetal outcome, products of conception (POC) samples were obtained. Simultaneous CNV-seq and WES was conducted to identify the fetal anomalies that can compress initial DNA and turnaround time of reports. RESULTS: In total, 959 couples were finally eligible for the enrollment. A total of 227 trios were identified with a causative alteration (CNV or variant), among which 191 (84.14%) were de novo. Double diagnosis of pathogenic CNVs and variants have been identified in 10 fetuses. The diagnostic yield of multisystem anomalies was significantly higher than single system anomalies (32.28% vs. 22.36%, P = 0.0183). The diagnostic rate of fetuses with consistent intra- and extra-uterine phenotypes (172/684) was significantly higher than the rate of these with inconsistent phenotypes (17/116, P = 0.0130). CONCLUSIONS: Simultaneous CNV-seq and WES analysis contributed to fetal anomaly diagnosis and played a vital role in elucidating complex anomalies with compound causes.


Asunto(s)
Diagnóstico Prenatal , Ultrasonografía Prenatal , Estudios de Cohortes , Femenino , Feto , Humanos , Embarazo , Primer Trimestre del Embarazo , Diagnóstico Prenatal/métodos , Ultrasonografía Prenatal/métodos , Secuenciación del Exoma/métodos
13.
Plant Physiol ; 186(1): 655-676, 2021 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-33576792

RESUMEN

Addressing the looming global food security crisis requires the development of high-yielding crops. In agricultural soils, deficiency in the micronutrient copper significantly decreases grain yield in wheat (Triticum aestivum), a globally important crop. In cereals, grain yield is determined by inflorescence architecture, flower fertility, grain size, and weight. Whether copper is involved in these processes, and how it is delivered to the reproductive organs is not well understood. We show that copper deficiency alters not only the grain set but also flower development in both wheat and its recognized model, Brachypodium distachyon. We then show that the Brachypodium yellow stripe-like 3 (YSL3) transporter localizes to the phloem, transports copper in frog (Xenopus laevis) oocytes, and facilitates copper delivery to reproductive organs and grains. Failure to deliver copper, but not iron, zinc, or manganese to these structures in the ysl3 CRISPR-Cas9 mutant results in delayed flowering, altered inflorescence architecture, reduced floret fertility, grain size, weight, and protein accumulation. These defects are rescued by copper supplementation and are complemented by YSL3 cDNA. This knowledge will help to devise sustainable approaches for improving grain yield in regions where soil quality is a major obstacle for crop production. Copper distribution by a phloem-localized transporter is essential for the transition to flowering, inflorescence architecture, floret fertility, size, weight, and protein accumulation in seeds.


Asunto(s)
Brachypodium/fisiología , Cobre/metabolismo , Proteínas de Transporte de Membrana/genética , Proteínas de Plantas/genética , Semillas/crecimiento & desarrollo , Brachypodium/genética , Proteínas de Transporte de Membrana/metabolismo , Proteínas de Plantas/metabolismo , Reproducción
14.
Pediatr Surg Int ; 38(8): 1113-1123, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35670846

RESUMEN

PURPOSE: To investigate the impact of COVID-19 on the treatment of children with congenital diaphragmatic hernia (CDH). METHODS: We retrospectively collected and compared the data of patients with CDH admitted between January 1, 2020 and December 31, 2021(study group) with the CDH patients admitted before the pandemic between January 1, 2018 and December 31, 2019 (control group). RESULTS: During the pandemic, 41 patients with CDH diagnosed prenatally were transferred to our hospital, and 40 underwent surgical repair. The number of patients treated in our hospital increased by 24.2% compared with the 33 patients before the pandemic. During the pandemic, the overall survival rate, postoperative survival rate and recurrence rate were 85.4%, 87.5% and 7.3%, respectively, and there were no significant differences compared with the control group (75.8%, 83.3% and 9.1%, respectively). The average length of hospital stay in patients admitted during the pandemic was longer than that in the control group (31 days vs. 16 days, P < 0.001), and the incidence of nosocomial infection was higher than that in the control group (19.5% vs. 3%, P = 0.037). CONCLUSIONS: CDH patients confirmed to be SARS-CoV-2 infection-free can receive routine treatment. Our data indicate that the implementation of protective measures during the COVID-19 pandemic, along with appropriate screening and case evaluation, do not have a negative impact on the prognosis of children.


Asunto(s)
COVID-19 , Hernias Diafragmáticas Congénitas , COVID-19/epidemiología , Niño , Hernias Diafragmáticas Congénitas/epidemiología , Hernias Diafragmáticas Congénitas/cirugía , Humanos , Pandemias , Estudios Retrospectivos , SARS-CoV-2
15.
Bioconjug Chem ; 32(8): 1915-1925, 2021 08 18.
Artículo en Inglés | MEDLINE | ID: mdl-34247477

RESUMEN

A three-dimensional (3D) printed biodegradable hydrogel scaffold with a strong self-expanding ability to conform to the contour of irregular bone defects and be closely adjacent to host tissues is reported herein. The scaffold has a triple cross-linked network structure consisting of photo-cross-linked polyacrylamide (PAAM) and polyurethane (PU) as the primary IPN network and chemical cross-linked gelatin (Gel) as the secondary network, which confers the scaffold with good mechanical properties. The addition of PU in the polymerization process of acrylamide (AAM) can improve the ultraviolet (UV) photocuring efficiency of the hydrogel and incorporate abundant hydrogen bonds between the PAAM copolymer chain and the PU chain. The results show that the hydrogel scaffold contains regular structures with smooth morphology, excellent dimensional stability, and uniform aperture. The degradation rate of the hydrogel scaffold is controllable through adjusting cross-linking agents and can be up to about 60% after degradation for 28 days. More importantly, the rapid self-inflating characteristic of the scaffold in water, that is, the volume of hydrogel scaffold can increase to about 8 times that of their own in an hour and can generate a slight compressive stress on the surrounding host tissue, thus stimulating the reconstruction and growth of new bone tissues. The in vitro experiment indicates that the scaffold is nontoxic and biocompatible. The in vivo experiment shows that the PU/PAAM/Gel chemically cross-linked scaffold displays the desirable osteogenic capability. This UV-curable 3D printed self-adaptive and degradable hydrogel scaffold holds great potential for nonload-bearing bone repair.


Asunto(s)
Implantes Absorbibles , Resinas Acrílicas/química , Gelatina/química , Poliuretanos/química , Impresión Tridimensional , Andamios del Tejido , Células 3T3 , Animales , Regeneración Ósea/efectos de los fármacos , Huesos/lesiones , Supervivencia Celular , Femenino , Hidrogeles , Ratones , Microscopía Electrónica de Rastreo , Osteoblastos/fisiología , Ratas
16.
J Pharmacol Exp Ther ; 374(2): 308-318, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32546528

RESUMEN

ME-344 is a second-generation cytotoxic isoflavone with anticancer activity promulgated through interference with mitochondrial functions. Using a click chemistry version of the drug together with affinity-enriched mass spectrometry, voltage-dependent anion channels (VDACs) 1 and 2 were identified as drug targets. To determine the importance of VDAC1 or 2 to cytotoxicity, we used lung cancer cells that were either sensitive (H460) or intrinsically resistant (H596) to the drug. In H460 cells, depletion of VDAC1 and VDAC2 by small interfering RNA impacted ME-344 effects by diminishing generation of reactive oxygen species (ROS), preventing mitochondrial membrane potential dissipation, and moderating ME-344-induced cytotoxicity and mitochondrial-mediated apoptosis. Mechanistically, VDAC1 and VDAC2 knockdown prevented ME-344-induced apoptosis by inhibiting Bax mitochondrial translocation and cytochrome c release as well as apoptosis in these H460 cells. We conclude that VDAC1 and 2, as mediators of the response to oxidative stress, have roles in modulating ROS generation, Bax translocation, and cytochrome c release during mitochondrial-mediated apoptosis caused by ME-344. SIGNIFICANCE STATEMENT: Dissecting preclinical drug mechanisms are of significance in development of a drug toward eventual Food and Drug Administration approval.


Asunto(s)
Antineoplásicos/farmacología , Isoflavonas/farmacología , Canal Aniónico 1 Dependiente del Voltaje/metabolismo , Canal Aniónico 2 Dependiente del Voltaje/metabolismo , Apoptosis/efectos de los fármacos , Línea Celular Tumoral , Humanos , Isoflavonas/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Proteína X Asociada a bcl-2/metabolismo
17.
Sensors (Basel) ; 20(5)2020 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-32151113

RESUMEN

The electromagnetic flowmeter is usually used for single-phase fluid parameter measurement. When the measured fluid is gas-liquid two-phase flow, the geometry of the sensor measurement space will change with the movement of the gas, which will cause measurement errors. The weight function distribution is an important parameter to analyze such measurement errors. The traditional method for calculating the weight function of gas-liquid two-phase flow involves complex dimensional space transformation, which is difficult to understand and apply. This paper presents a new method for calculating the weight function of the gas-liquid two-phase flow electromagnetic flowmeter. Firstly, based on the measurement principle of the electromagnetic flowmeter, a general model of weight function of the gas-liquid two-phase flow electromagnetic flowmeter is built. Secondly, the bubbles in the fluid are regarded as the "isolated" points in the flow field. According to the physical connection between the "field" of the measured fluid and the "source" of the sensor electrode, the Green's function expression based on gas-liquid two-phase flow is established. Then, combined with the boundary conditions of the measurement space of the electromagnetic flowmeter, the Green's function is analyzed. Finally, the general model of weight function is solved by using the expression of Green's function, then the expression of the weight function of the electromagnetic flowmeter is obtained when the measured fluid is hybrid gas-liquid two-phase flow. The simulation results show that the proposed method can reasonably describe the influence of the gas in the measured fluid on the output signal of the sensor, and the experimental results also indirectly prove the rationality of this method.

18.
Mol Cell Biochem ; 440(1-2): 189-197, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28828564

RESUMEN

Glucocorticoids are commonly used for the treatment of pancreatitis and complicated acute lung injury and help to reduce the mortality rates of both. The effect of gene variants in heat shock protein 90 (Hsp90), a key chaperone molecule of the glucocorticoid receptor (GR), on the therapeutic effect of glucocorticoids is unclear. Our study aims to investigate the different susceptibility to glucocorticoid treatment in BALB/c and C57BL/6 mice carrying different Hsp90 genotypes in an animal model of pancreatitis-induced lung injury. Compared with BALB/c mice, C57BL/6 mice have lower mortality rates, decreased water content in their lungs, and a lower level of IL-1 beta in an animal model of acute pancreatitis. C57BL/6 mice show a greater therapeutic effect and increased GR binding activities with glucocorticoid responsive element compared to BALB/c mice after a 0.4 mg/kg dexamethasone (DEX) treatment. Treatment with a higher dose of DEX (4 mg/kg) significantly reduced mortality rates and increased GR-GRE binding activity in both strains of mice, and there was no significant difference between the two strains. DEX did not exert a protective role after geldanamycin, a specific inhibitor of Hsp90, was administered in both strains of mice. Our study revealed that Hsp90 gene variants are responsible for the greater therapeutic effect of DEX in C57BL/6 mice compared to BALB/c mice, which implies that combining DEX treatment with Hsp90 regulation would promote the efficiency of DEX and would be an effective way to alleviate the side effects of hormone therapy.


Asunto(s)
Dexametasona/farmacología , Proteínas HSP90 de Choque Térmico/metabolismo , Lesión Pulmonar , Pulmón/metabolismo , Pancreatitis , Receptores de Glucocorticoides/metabolismo , Animales , Interleucina-1beta/metabolismo , Pulmón/patología , Lesión Pulmonar/tratamiento farmacológico , Lesión Pulmonar/etiología , Lesión Pulmonar/metabolismo , Lesión Pulmonar/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Pancreatitis/complicaciones , Pancreatitis/tratamiento farmacológico , Pancreatitis/metabolismo , Pancreatitis/patología
19.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi ; 35(3): 357-360, 2018 Jun 10.
Artículo en Zh | MEDLINE | ID: mdl-29896731

RESUMEN

OBJECTIVE: To assess the application value in prenatal diagnosis using karyotype analysis combined with BACs-on-Beads (BoBs) assay. METHODS: Nine hundred sixty five pregnant women were subjected to amniocentesis, chromosomal karyotype analysis and detection of BoBs were employed simultaneously for abnormal number of chromosomes and 9 chromosome microdeletion syndrome in prenatal diagnosis. RESULTS: Fifty cases common chromosome aneupoidies were successfully detected by both karyotype analysis and BoBs which included 31 cases of trisomy 21,10 cases of trisomy 18 and 9 cases with sex chromosome abnormality. BoBs in addition detected 1 case of DiGeorge-1 microdeletion syndrome and 1 case of 7q11.23 microduplication syndrome. All 9 fetuses with chromosome abnormalities detected by karyotyping were missed by BoBs, including 2 cases of marker chromosomes,4 cases of chromosomal translocation,1 case of chromosomal inversion, 2 cases of Sex chromosome mosaicism; 2 cases of fetal inherited from the parents,7 cases for novel mutations. CONCLUSION: Karyotype analysis combined with BoBs dedtection is a rapid, effective and highly accurate prenatal diagnosis model that may should be widely used in clinical diagnosis.


Asunto(s)
Trastornos de los Cromosomas/genética , Enfermedades Fetales/genética , Cariotipificación/métodos , Diagnóstico Prenatal/métodos , Adulto , Aberraciones Cromosómicas , Trastornos de los Cromosomas/embriología , Cromosomas Artificiales Bacterianos/genética , Femenino , Enfermedades Fetales/diagnóstico , Humanos , Cariotipificación/instrumentación , Masculino , Embarazo , Diagnóstico Prenatal/instrumentación , Aberraciones Cromosómicas Sexuales/embriología
20.
Cell Physiol Biochem ; 41(5): 2016-2026, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28420001

RESUMEN

BACKGROUND: Nickel compounds are well-established human carcinogens with weak mutagenic activity. Histone methylation has been proposed to play an important role in nickel-induced carcinogenesis. Nicotinamide N-methyltransferase (NNMT) decreases histone methylation in several cancer cells by altering the cellular ratio of S-adenosylmethionine (SAM) to S-adenosylhomocysteine (SAH). However, the role of NNMT in nickel-induced histone methylation remains unclear. METHODS: BEAS-2B cells were exposed to different concentrations of nickel chloride (NiCl2) for 72 h or 200 µM NiCl2 for different time periods. Histone H3 on lysine 9 (H3K9) mono-, di-, and trimethylation and NNMT protein levels were measured by western blot analysis. Expressions of NNMT mRNA and the H3k9me2-associated genes, mitogen-activated protein kinase 3 (MAP2K3) and dickkopf1 (DKK1), were determined by qPCR analysis. The cellular ratio of nicotinamide adenine dinucleotide (NAD+) to reduced NAD (NADH) and SAM/SAH ratio were determined. RESULTS: Exposure of BEAS-2B cells to nickel increased H3K9 dimethylation (H3K9me2), suppressed the expressions of H3K9me2-associated genes (MAP2K3 and DKK1), and induced NNMT repression at both the protein and mRNA levels. Furthermore, over-expression of NNMT inhibited nickel-induced H3K9me2 and altered the cellular SAM/SAH ratio. Additionally, the NADH oxidant phenazine methosulfate (PMS) not only reversed the nickel-induced reduction in NAD+/NADH but also inhibited the increase in H3K9me2. CONCLUSIONS: These findings indicate that the repression of NNMT may underlie nickel-induced H3K9 dimethylation by altering the cellular SAM/SAH ratio.


Asunto(s)
Histonas/metabolismo , Níquel/farmacología , Nicotinamida N-Metiltransferasa/metabolismo , S-Adenosilhomocisteína/metabolismo , S-Adenosilmetionina/metabolismo , Línea Celular , Histonas/genética , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , MAP Quinasa Quinasa 3/genética , MAP Quinasa Quinasa 3/metabolismo , Metilación/efectos de los fármacos , Nicotinamida N-Metiltransferasa/genética
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