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1.
Front Microbiol ; 15: 1335488, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38500586

RESUMEN

Soil microorganisms play an important role in regulating and contributing to carbon cycling processes in grassland ecosystems. Soil salinization is one of the major problems causing soil degradation, and its effects on carbon cycle immobilization-related functional genes in soil microorganisms remain unknown. Therefore, we took Songnen salinization grassland as the research object, selected grasslands with different salinization levels, and explored the diversity of soil microorganisms and functional genes related to carbon cycling in Songnen grassland with different salinization levels through metagenomic technology. The results showed that with the increase of salinity, the relative abundance of Ascomycetes increased, while the relative abundance of Proteus and Firmicutes decreased. In addition, the relative abundance of functional genes related to carbon cycling fixation has also decreased. As the degree of soil salinization increases, the relative abundance of glycoside hydrolases (GH)130 family significantly increases, while the relative abundance of soil carbohydrate enzymes belonging to GH3 and GH55 families significantly decreases. Using structural equation modeling (SEM), it was found that soil pH and conductivity (EC) have a significant impact on soil microbial diversity and functional genes related to carbon cycling fixation. The increase in soil pH directly reduces the Shannon diversity of soil microbial diversity and functional genes related to carbon cycling fixation. Therefore, it can be concluded that the intensification of grassland salinization reduces the diversity of bacteria and fungi, and affects the diversity of functional genes related to carbon cycling fixation by reducing the total diversity of bacteria. The increase in salinity has a negative feedback effect on grassland soil carbon cycling. This study provides a theoretical framework for grassland soil carbon sequestration and degradation restoration.

2.
Front Pediatr ; 12: 1345602, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38487473

RESUMEN

Background: Neonatal hyperbilirubinemia (NHB) is one of the most common diseases in the neonatal period. Without timely diagnosis and treatment, it can lead to long-term complications. In severe cases, it may even result in fatality. The UGT1A1 gene and clinical risk factors play important roles in the development and progression of NHB. Methods: In this study, we conducted a cohort study and analyzed 3258 newborns from the Jilin Women And Children Health Hospital in northern China, including 372 children with hyperbilirubinemia. We established a predictive model using a logistic regression model based on clinical risk factors and the polymorphism of the G211A locus in the UGT1A1 gene of newborns. Furthermore, the performance of the prediction model was evaluated using the ROC curve. Results: The logistic regression model indicates that the following factors are associated with an increased risk of NHB: the time when stool turns yellow [P ≤ 0.001, OR 1.266 (95% CI: 1.125-1.425)]; neonatal cephalohematoma [P ≤ 0.001, OR 33.642 (95% CI: 21.823-51.861)]; hemolytic disease of newborn [P ≤ 0.001, OR 33.849 (95% CI: 18.589-61.636)]; neonatal weight loss [P ≤ 0.001, OR 11.275 (95% CI: 7.842-16.209)]; neonatal premature rupture of membranes (PROM) history [P = 0.021, OR 1.422 (95% CI: 1.056-1.917)]; genetic polymorphism at the UGT1A1 gene G211A locus. Gestational age is a protective factor [P ≤ 0.001, OR 0.766 (95% CI: 0.686-0.855)]. Compared to natural labor, cesarean section is a protective factor [P = 0.011, OR 0.711 (95% CI: 0.546-0.926)], while assisted delivery is a risk factor [P = 0.022, OR 2.207 (95% CI: 1.121-4.346)]. The area under the curve (AUC) of this prediction model is 0.804 (95% CI: 0.777-0.831), indicating good discrimination ability and value for predicting the risk of NHB after birth. Conclusion: We have developed and evaluated a predictive model that combines UGT1A1 gene polymorphism and clinical risk factors for the first time. By using this nomogram and taking into account the results of serum total bilirubin measurement or transcutaneous bilirubin measurement, early prediction of the risk of neonatal hyperbilirubinemia can be achieved.

3.
Acta Biomater ; 160: 73-86, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36804823

RESUMEN

The irrational use of natural compounds in the treatment of diseases can lead to serious side effects, especially hepatoxicity, and its toxic effects are usually cumulative and imperceptible. Therefore, an accurate sensing platform is urgently needed to monitor the hepatotoxicity of natural compounds. Here, we deposited a thermo-responsive alginate-RGD/Pluronic hydrogel to construct an in vitro three-dimensional(3D) hepar-platform, and a thorough validation was adopted to evaluate the bioprinted hepatic constructs. The engineered hepar-platform was then employed to access its biological response toward Emodin (EM) and Triptolide (TP), two typical hepatotoxic natural compounds. Subsequently, we integrated it with a robust fluorescent sensor based on hybridization chain reaction amplification strategy (HCR) to monitor the early hepatotoxic biomarker - glutathione-S-transferase-alpha (GST-α) secreted by this 3D constructs. Our study was the first attempt to construct an accurate hepar-on-a-sensor platform that could effectively detect GST-α for monitoring the hepatoxic effects of natural compounds. The limit of detection of the platform was 0.3 ng ml-1 and the accuracy of this platform was verified by enzyme linked immunosorbent assay. Furthermore, the variation of GST-α induced by EM and TP was consistent with hepatotoxicity studies, thus providing an important application value for evaluating the hepatotoxicity of natural compounds. STATEMENT OF SIGNIFICANCE: 1. We deposited a thermo-responsive alginate-RGD/Pluronic hydrogel to construct an in vitro three-dimensional(3D) hepar-platform, and elucidated the essential reasons why hybrid bioinks more suitable for 3D extrusion from biomaterials itself. Also, a thorough validation associated with a series of important proteins and genes involved in liver cell metabolism was adopted to evaluate the bioprinted hepatic constructs accurately 2. Glutathione-S-transferase-alpha is a soluble trace biomarker for acute hepatotoxic injury, the hepatotoxic effects of natural compounds on the secretion of GST-α has not been reported to date. We integrated our 3D hepar-platform with recognition molecules-aptamers and HCR amplification strategy to monitor the variation of GST-α, aiming at developing a robust and stable fluorescent biosensing platform to monitor the hepatoxicity of natural compounds.


Asunto(s)
Bioimpresión , Enfermedad Hepática Inducida por Sustancias y Drogas , Humanos , Poloxámero , Hidrogeles , Biomarcadores , Colorantes , Alginatos , Glutatión , Oligopéptidos , Impresión Tridimensional , Andamios del Tejido , Ingeniería de Tejidos
4.
Anal Chim Acta ; 1239: 340642, 2023 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-36628744

RESUMEN

Norcantharidin (NCTD), a demethylated derivative of cantharidin, is an anticancer active component in traditional Chinese medicine. At present, the main methods for finding its target proteins are pharmacological methods and biophysical screening, which cannot achieve the purpose of efficient and accurate screening. Here we established a new analytical method for specific fishing and assisted imaging for norcantharidin target proteins. For the AIE supramolecule probe, the benzophenone azide (BPA) fluorescent nanoparticles with strong AIE properties were encapsulated in biocompatible DSPE-PEG that covalently coupled with NCTD (named BPA@NCTD NPs). The target proteins of NCTD can be captured by BPA@NCTD NPs, and then be detected to investigate the potential signaling pathways. The screened differential proteins were analysed through the protein and signaling pathway database, and multiple signaling pathways were obtained and verified. The mechanism of norcantharidin in inhibiting the migration and invasion of A549 cells through the P53 signaling pathway was confirmed by Western blot experiments. Our research showed that AIE supramolecule probe BPA@NCTD NPs has the dual functions of specific screening of A549 cells target proteins and biological imaging, which not only offers a good anti-fluorescence quenching ability for the dynamic imaging process of NCTD, but also provides a novel and efficient specific method for efficient analysis of target proteins and signal pathways.


Asunto(s)
Compuestos Bicíclicos Heterocíclicos con Puentes , Transducción de Señal , Línea Celular Tumoral , Apoptosis , Proliferación Celular
5.
Environ Sci Pollut Res Int ; 30(9): 22550-22559, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36301385

RESUMEN

Cadmium (Cd) is a food contaminant that poses serious threats to animal health, including birds. It is also an air pollutant with well-known neurotoxic effects on humans. However, knowledge on the neurotoxic effects of chronic Cd exposure on chicken is limited. Thus, this study assessed the neurotoxic effects of chronic Cd on chicken cerebellum. Chicks were exposed to 0 (control), 35 (low), and 70 (high) mg/kg of Cd for 90 days, and the expression of genes related to the heat-shock response was investigated. The chickens showed clinical symptoms of ataxia, and histopathology revealed that Cd exposure decreased the number of Purkinje cells and induced degeneration of Purkinje cells with pyknosis, and some dendrites were missing. Moreover, Cd exposure increased the expression of heat-shock factors, HSF1, HSF2, and HSF3, and heat-shock proteins, HSP60, HSP70, HSP90, and HSP110. These changes indicate that HSPs improve the tolerance of the cerebellum to Cd. Conversely, the expressions of HSP10, HSP25, and HSP40 were decreased significantly, which indicated that Cd inhibits the expression of small heat-shock proteins. However, HSP27 and HSP47 were upregulated following low-dose Cd exposure, but downregulated under high-dose Cd exposure. This work sheds light on the toxic effects of Cd on the cerebellum, and it may provide evidence for health risks posed by Cd. Additionally, this work also identified a novel target of Cd exposure in that Cd induces cerebellar injury by disrupting the heat-shock response. Cd can be absorbed into chicken's cerebellum through the food chain, which eventually caused cerebellar injury. This study provided a new insight that chronic Cd-induced neurotoxicity in the cerebellum is associated with alterations in heat-shock response-related genes, which indicated that Cd through disturbing heat-shock response induced cerebellar injury.


Asunto(s)
Cadmio , Pollos , Humanos , Animales , Cadmio/toxicidad , Respuesta al Choque Térmico , Proteínas HSP70 de Choque Térmico , Cerebelo
6.
Materials (Basel) ; 15(21)2022 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-36363402

RESUMEN

Selective laser melting manufacture of patient specific Ti implants is serving as a promising approach for bone tissue engineering. The success of implantation is governed by effective osseointegration, which depends on the surface properties of implants. To improve the bioactivity and osteogenesis, the universal surface treatment for SLM-Ti implants is to remove the primitive roughness and then reengineer new roughness by various methods. In this study, the micro-sized partially melted Ti particles on the SLM-Ti surface were preserved for assembling mesoporous bioactive glass nanospheres to obtain a unique micro/nano- topography through combination of SLM manufacture and sol-gel processes. The results of simulated body fluid immersion test showed that bioactive ions (Ca, Si) can be continuously and stably released from the MBG nanospheres. The osseointegration properties of SLM-Ti samples, examined using pre-osteoblast cells, showed enhanced adhesion and osteogenic differentiation compared with commercial pure titanium commonly used as orthopedic implants. Overall, the developed approach of construction of the dual micro/nano topography generated on the SLM-Ti native surface could be critical to enhance musculoskeletal implant performance.

7.
Biomater Sci ; 10(5): 1209-1216, 2022 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-35107108

RESUMEN

Diabetes can cause various complications and affect the normal functioning of the human body. A theranostic and diagnostic platform for real-time glycemia sensing and simultaneous self-regulated release of insulin is desired to improve diabetic patients' life quality. Here, we describe a theranostic microneedle array patch, which enables the achievement of visualization quantification of glycemia and simultaneously self-regulated release of insulin. The microneedle patch (MNDF) was fabricated by crosslinking of 3-aminophenylboronic acid (ABA)-modified sodium alginate and chondroitin sulfate. The hierarchical structure consisted of a tip part containing mineralized insulin particles and glucose oxidase (GOD) for insulin release, and a base surface embodying 3,3',5,5'-tetramethylbenzidine (TMB) and (horseradish peroxidase) HRP for real-time glycemia sensing. In the presence of glucose, GOD converts glucose into H+ and H2O2, driving gradual dissolution of the calcium layer of insulin particles, resulting in long-acting release of insulin. By the bio-catalytic action of HRP, the generated H2O2 brings about a visible color change allowing the glucose level at the base surface to be read out. We believe that the theranostic microneedle array patch can act as a promising alternative for future clinical applications.


Asunto(s)
Diabetes Mellitus Experimental , Insulina , Animales , Glucemia , Diabetes Mellitus Experimental/tratamiento farmacológico , Humanos , Peróxido de Hidrógeno/química , Insulina/química , Medicina de Precisión
8.
Adv Healthc Mater ; 10(19): e2100764, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34028989

RESUMEN

Recently, some metabolites in skin interstitial fluid (SIF) have become emerging re×sources for early disease diagnosis. However, their low level in SIF and difficulty to sampling are the biggest obstacle to further potential application. Here, a swellable microneedle array patch (MNAP) with high mechanical strength is presented, and the rapid enrichment of positively charged metabolites is achieved. The MNAP is fabricated by poly (chondroitin sulfate-acrylamido-2-methylpropane sulfonic acid)-gold nanoparticles (GNPs) composites via a micro-molding. The negatively charged copolymer hydrogel not only enrich positively charged metabolites, but also provide swellable capacity. The in situ synthesis of GNPs in the process of copolymerization make the GNPs cross-link to the hydrogel, which further enhance the MNAP mechanical strength and enrichment efficiency for positively charged metabolites. By using the MNAP, around 5 mg SIF in 10 min from the high fat/cholecalciferol/methimazole-induced atherogenesis rat is extracted and 23 metabolites including 13 quaternary ammonium cationic compounds can be detected and quantified by using a LC-QTOF-MS. Dysregulated L-carnitine and choline metabolism are discovered a week earlier in the SIF than in the serum, achieving early diagnosis of the metabolism syndrome disease. This MNAP also helps users complete home sampling for early disease diagnosis and monitoring.


Asunto(s)
Nanopartículas del Metal , Agujas , Animales , Diagnóstico Precoz , Oro , Ratas , Piel
9.
IEEE Trans Vis Comput Graph ; 26(12): 3503-3513, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32941146

RESUMEN

Thermally modulated Nanophotonic Phased Arrays (NPAs) can be used as phase-only holographic displays. Compared to the holographic displays based on Liquid Crystal on Silicon Spatial Light Modulators (LCoS SLMs), NPAs have the advantage of integrated light source and high refresh rate. However, the formation of the desired wavefront requires accurate modulation of the phase which is distorted by the thermal proximity effect. This problem has been largely overlooked and existing approaches to similar problems are either slow or do not provide a good result in the setting of NPAs. We propose two new algorithms based on the iterative phase retrieval algorithm and the proximal algorithm to address this challenge. We have carried out computational simulations to compare and contrast various algorithms in terms of image quality and computational efficiency. This work is going to benefit the research on NPAs and enable the use of large-scale NPAs as holographic displays.

10.
Metallomics ; 10(5): 751-758, 2018 05 23.
Artículo en Inglés | MEDLINE | ID: mdl-29766197

RESUMEN

Selenoprotein W (SelW) is an important member of the avian selenoprotein family. It is well known for its important role in protecting neurons from oxidative stress during neuronal development. d-Amino acid (d-serine), as a neurotransmitter in the central nervous system (CNS), can mediate neurotoxicity. d-Amino acid oxidase (DAAO) is responsible for regulating the d-serine levels in cells. However, the correlation between SelW and DAAO is not clear yet. To investigate the regulations between SelW and DAAO, chicken embryo monolayer neurons were treated with d-serine and/or Se. In this study, we predicted molecular binding between SelW and DAAO. These results showed that the 9-16, 18, 41-47 and 66 residues of SelW could combine with the DAAO, which suggested that chicken SelW might be the target of DAAO. We determined the DAAO activity and the mRNA expression of SelW in in vitro cultured chicken embryo primitive neuron cells. d-Serine influenced the activity of DAAO and, moreover, a significant increase in the mRNA expression of SelW was found in neurons treated with Se. Notably, we also observed changes in the expression of SelW and DAAO when neurons were treated with various concentrations of d-serine and Se. In conclusion, these data suggest that d-serine could regulate the mRNA expression of SelW by interfering with the activity of DAAO in chicken embryo neurons.


Asunto(s)
D-Aminoácido Oxidasa/metabolismo , Regulación de la Expresión Génica , Neuronas/metabolismo , Selenoproteína W/metabolismo , Serina/farmacología , Animales , Supervivencia Celular , Células Cultivadas , Embrión de Pollo , Pollos , D-Aminoácido Oxidasa/genética , Proyección Neuronal , Neuronas/citología , Neuronas/efectos de los fármacos , Estrés Oxidativo , Selenio/farmacología , Selenoproteína W/genética
11.
Toxicol In Vitro ; 44: 349-356, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28765097

RESUMEN

Cadmium (Cd) is a ubiquitously distributed trace metal and environmental pollutant that is highly toxic to liver. Selenium (Se) may provide chemoprotection against Cd-induced cytotoxicity by augmenting the cellular antioxidant capacity. However, the mechanism of Se chemoprotection against Cd-induced hepatotoxicity is unclear. The present study evaluated the ameliorative properties of Se against Cd-induced cytotoxicity in hepatocytes. Primary cells were exposed to 5µM Cd and/or 1µM Se for 24h. Cellular morphology and function, antioxidant status, activation of Nrf2 pathway, autophagy and apoptosis were determined. These results indicated that Se ameliorated the cytotoxicity of Cd by recovering hepatocyte morphology and function, inhibiting reactive oxygen species (ROS) and malondialdehyde (MDA) production, reducing intracellular LDH release, autophagy and apoptosis, and increasing the major antioxidative activities (Total antioxidant capacity (T-AOC) and superoxide dismutase (SOD). In summary, Cd is a hepatotoxin that causes hepatocytes damage by inducing oxidative stress, excessive autophagy and apoptosis as a mechanism of toxicity. Moreover, Se supplement ameliorated these effects by enhancing antioxidant systems, decreasing excessive autophagy and apoptosis. These results suggested that Se triggers Nrf2-mediated protection as the mechanism of Se chemoprotection against Cd-induced autophagy and apoptosis.


Asunto(s)
Cadmio/toxicidad , Hepatocitos/efectos de los fármacos , Factor 2 Relacionado con NF-E2/genética , Factor 2 Relacionado con NF-E2/metabolismo , Sustancias Protectoras/farmacología , Selenio/farmacología , Animales , Apoptosis/efectos de los fármacos , Autofagia/efectos de los fármacos , Pollos , Glutamato-Cisteína Ligasa/genética , Glutatión Transferasa/genética , Hemo-Oxigenasa 1/genética , Hepatocitos/metabolismo , Peroxidación de Lípido/efectos de los fármacos , Malondialdehído/metabolismo , NAD(P)H Deshidrogenasa (Quinona)/genética , Especies Reactivas de Oxígeno/metabolismo , Superóxido Dismutasa/metabolismo
12.
Oncotarget ; 8(22): 35919-35932, 2017 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-28415800

RESUMEN

Selenophosphate synthetase (SPS) is essential for selenoprotein biosynthesis. In two SPS paralogues, SPS1 was only cloned from a cDNA library prepared from avian organ. However, the biological function of SPS1 in chicken central nervous system (CNS) remains largely unclear. To investigate the role of avian SPS1 in the development and selenium (Se) homeostasis of CNS, fertile eggs, chicken embryos, embryo neurons and chicks were employed in this study. The response of SPS1 transcription to the development and Se levels of CNS tissues was analyzed using qRT-PCR. SPS1 gene exists extensively in the development of chicken CNS. The wide expression of avian SPS1 can be controlled by the Se content levels, which suggests that SPS1 is important in the regulation of Se homeostasis. The fundamental mechanism of these effects is that Se alters the half-life and stability of SPS1 mRNA. Therefore, SPS1 exerts an irreplaceable biological function in chicken CNS and Se homeostasis is closely related to the expression of SPS1. These results suggested that SPS1 was required for the development and Se homeostasis of CNS in chicken.


Asunto(s)
Sistema Nervioso Central/embriología , Sistema Nervioso Central/metabolismo , Homeostasis , Fosfotransferasas/genética , Fosfotransferasas/metabolismo , Selenio/metabolismo , Animales , Supervivencia Celular/efectos de los fármacos , Pollos , Suplementos Dietéticos , Expresión Génica , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Estabilidad del ARN , ARN Mensajero/genética , ARN Mensajero/metabolismo , Compuestos de Selenio/farmacología
13.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 7): m933, 2011 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-21836917

RESUMEN

In the title mononuclear complex, [Zn(C(7)H(4)NO(4))(2)(C(8)H(8)N(2)S)(2)], the Zn(II) atom is coordinated by two N atoms from two 2-amino-6-methyl-1,3-benzothia-zole and by two carboxylate O atoms from two 4-nitro-benzoate ligands, adopting a slightly distorted tetra-hedral coordination geometry. In the crystal, inter-molecular N-H⋯O hydrogen bonds between the amino group of 2-amino-6-methyl-1,3-benzothia-zole and the carboxyl-ate group of 4-nitro-benzoate link these discrete mononuclear units into a one-dimensional supra-molecular chain extending parallel to [100].

14.
Org Lett ; 10(3): 361-4, 2008 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-18163635

RESUMEN

Solid-state silica-gel-catalyzed opening of aziridine 6 provided phenanthrene 7, whose oxidative cleavage, recyclization, and further elaboration furnished the C-1 aldehyde and carboxylic acid derivatives of 7-deoxypancratistatin for potential analogue synthesis.


Asunto(s)
Alcaloides de Amaryllidaceae/síntesis química , Aziridinas/química , Isoquinolinas/síntesis química , Fenantrenos/química , Alcaloides de Amaryllidaceae/química , Ácidos Carboxílicos , Catálisis , Ciclización , Isoquinolinas/química , Estructura Molecular
15.
Org Lett ; 7(25): 5669-72, 2005 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-16321018

RESUMEN

[chemical reaction: see text]. A derivative of pancratistatin having no oxygenation in the aromatic ring was synthesized by a new strategy based on the cobalt-catalyzed cyclotrimerization of acetylenes as a prelude to diversity-oriented synthesis of further analogues.


Asunto(s)
Alcaloides de Amaryllidaceae/síntesis química , Isoquinolinas/síntesis química , Liliaceae/química , Alcaloides de Amaryllidaceae/química , Catálisis , Cobalto/química , Ciclización , Isoquinolinas/química , Estructura Molecular
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