Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 182
Filtrar
2.
Rev Sci Instrum ; 92(9): 094102, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34598534

RESUMO

The wireless capsule endoscopy (WCE) procedure produces tens of thousands of images of the digestive tract, for which the use of the manual reading process is full of challenges. Convolutional neural networks are used to automatically detect lesions in WCE images. However, studies on clinical multilesion detection are scarce, and it is difficult to effectively balance the sensitivity to multiple lesions. A strategy for detecting multiple lesions is proposed, wherein common vascular and inflammatory lesions can be automatically and quickly detected on capsule endoscopic images. Based on weakly supervised learning, EfficientNet is fine-tuned to extract the endoscopic image features. Combining spatial features and channel features, the proposed attention network is then used as a classifier to obtain three classifications. The accuracy and speed of the model were compared with those of the ResNet121 and InceptionNetV4 models. It was tested on a public WCE image dataset obtained from 4143 subjects. On the computer-assisted diagnosis for capsule endoscopy database, the method gives a sensitivity of 96.67% for vascular lesions and 93.33% for inflammatory lesions. The precision for vascular lesions was 92.80%, and that for inflammatory lesions was 95.73%. The accuracy was 96.11%, which is 1.11% higher than that of the latest InceptionNetV4 network. Prediction for an image only requires 14 ms, which balances the accuracy and speed comparatively better. This strategy can be used as an auxiliary diagnostic method for specialists for the rapid reading of clinical capsule endoscopes.

3.
Artigo em Inglês | MEDLINE | ID: mdl-34506620

RESUMO

Rapeseed contains high levels of glucosinolates (GSLs), playing pivotal roles in defense against herbivores and pests. As their presence in rapeseed reduces the value of the meal for animal feeding, intensive efforts to reduce them produced low-seed GSL cultivars. However, there is no such variety suitable for the south part of Japan. Here, we tested the effects of cold oxygen plasma (oxygen CP) on seed germination and GSL and lipid content, in three rapeseed cultivars. According to the cultivars, oxygen CP slightly stimulated seed germination and modified the GSL levels; decreased GSL levels in Westar and Kizakinonatane but increased those in Nanashikibu. In contrast, it negligibly affected the lipid content and composition in the three cultivars. Thus, oxygen CP modulated seed GSL levels without affecting seed viability and lipid content. Future optimization of this technique may help optimize rapeseed GSL content without plant breeding.

4.
J Nanobiotechnology ; 19(1): 268, 2021 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-34488792

RESUMO

BACKGROUND: Tumor-associated macrophages (TAMs) are the most abundant stromal cells in the tumor microenvironment. Turning the TAMs against their host tumor cells is an intriguing therapeutic strategy particularly attractive for patients with immunologically "cold" tumors. This concept was mechanistically demonstrated on in vitro human and murine lung cancer cells and their corresponding TAM models through combinatorial use of nanodiamond-doxorubicin conjugates (Nano-DOX) and a PD-L1 blocking agent BMS-1. Nano-DOX are an agent previously proved to be able to stimulate tumor cells' immunogenicity and thereby reactivate the TAMs into the anti-tumor M1 phenotype. RESULTS: Nano-DOX were first shown to stimulate the tumor cells and the TAMs to release the cytokine HMGB1 which, regardless of its source, acted through the RAGE/NF-κB pathway to induce PD-L1 in the tumor cells and PD-L1/PD-1 in the TAMs. Interestingly, Nano-DOX also induced NF-κB-dependent RAGE expression in the tumor cells and thus reinforced HMGB1's action thereon. Then, BMS-1 was shown to enhance Nano-DOX-stimulated M1-type activation of TAMs both by blocking Nano-DOX-induced PD-L1 in the TAMs and by blocking tumor cell PD-L1 ligation with TAM PD-1. The TAMs with enhanced M1-type repolarization both killed the tumor cells and suppressed their growth. BMS-1 could also potentiate Nano-DOX's action to suppress tumor cell growth via blocking of Nano-DOX-induced PD-L1 therein. Finally, Nano-DOX and BMS-1 achieved synergistic therapeutic efficacy against in vivo tumor grafts in a TAM-dependent manner. CONCLUSIONS: PD-L1/PD-1 upregulation mediated by autocrine and paracrine activation of the HMGB1/RAGE/NF-κB signaling is a key response of lung cancer cells and their TAMs to stress, which can be induced by Nano-DOX. Blockade of Nano-DOX-induced PD-L1, both in the cancer cells and the TAMs, achieves enhanced activation of TAM-mediated anti-tumor response.

5.
J Hazard Mater ; 416: 126183, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492954

RESUMO

In this work, a modified g-C3N4/MgZnAl-calcined layered double hydroxide composite (M-CN/cLDH) was successfully fabricated via a template method. The composite material is a hierarchical porous flower-like nanostructure self-assembled from stacked hybrid flakes. The 3D M-CN/cLDH architectures exhibit a synergistic effect of adsorption and photocatalysis for eliminating typical tetracycline antibiotics in seawater, i.e., oxytetracycline (OTC), tetracycline (TC), chlortetracycline (CTC), and doxycycline (DXC). The synergistic removal rate of OTC in seawater of M-CN/cLDH is 2.73 times higher than that of g-C3N4 after 120 min of visible-light illumination, and M-CN/cLDH also performs better adsorption-photocatalytic degradation on OTC in the continuous flow reaction process. The superior adsorption capability of the M-CN/cLDH is attributed to the open porous structures of cLDH, and its excellent photocatalytic degradation activity is ascribed to the closely bonded heterojunctions between g-C3N4 (CN) and cLDH double layers. The mass spectra reveals the degradation pathways of OTC, and its byproducts are less toxic after degradation for 120 min. The exploration of the M-CN/cLDH in synthetic mariculture wastewater suggested a huge potential for its practical application. With the assistance of magnesium ammonium phosphate (MAP) precipitation pretreatment, the material can effectively retain the high OTC removal rate in the synthetic mariculture wastewater circumstance.


Assuntos
Antibacterianos , Águas Residuárias , Adsorção , Catálise , Porosidade , Água do Mar
6.
Molecules ; 26(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34443601

RESUMO

Surfactant aggregates have long been considered as a tool to improve drug delivery and have been widely used in medical products. The pH-responsive aggregation behavior in anionic gemini surfactant 1,3-bis(N-dodecyl-N-propanesulfonate sodium)-propane (C12C3C12(SO3)2) and its mixture with a cationic monomeric surfactant cetyltrimethylammonium bromide (CTAB) have been investigated. The spherical-to-wormlike micelle transition was successfully realized in C12C3C12(SO3)2 through decreasing the pH, while the rheological properties were perfectly enhanced for the formation of wormlike micelles. Especially at 140 mM and pH 6.7, the mixture showed high viscoelasticity, and the maximum of the zero-shear viscosity reached 1530 Pa·s. Acting as a sulfobetaine zwitterionic gemini surfactant, the electrostatic attraction, the hydrogen bond and the short spacer of C12C3C12(SO3)2 molecules were all responsible for the significant micellar growth. Upon adding CTAB, the similar transition could also be realized at a low pH, and the further transformation to branched micelles occurred by adjusting the total concentration. Although the mixtures did not approach the viscosity maximum appearing in the C12C3C12(SO3)2 solution, CTAB addition is more favorable for viscosity enhancement in the wormlike-micelle region. The weakened charges of the headgroups in a catanionic mixed system minimizes the micellar spontaneous curvature and enhances the intermolecular hydrogen-bonding interaction between C12C3C12(SO3)2, facilitating the formation of a viscous solution, which would greatly induce entanglement and even the fusion of wormlike micelles, thus resulting in branched microstructures and a decline of viscosity.


Assuntos
Reologia , Tensoativos/química , Cetrimônio/química , Glutamatos/química , Concentração de Íons de Hidrogênio , Micelas , Viscosidade
7.
Biomacromolecules ; 2021 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-34378928

RESUMO

The cryopreservation (CP) of cell/tissue is indispensable in medical science. However, the formation of ice during cooling and ice recrystallization/growth in time of thawing present significant risk of cell/tissue damage upon analysis of CP process. Herein, the natural and biocompatible silk fibroin (SF) with regular hydrophobic and hydrophilic domains, were first employed as a cryoprotectant (CPA), to the CP of human bone-derived mesenchymal stem cells (hBMSCs), which has been routinely cyropreserved for cell-based therapies. Addtion of SF can regulate the formation of ice crystals during cooling process because of its strong hydration ability in the comparation to the cryopreservation medium (CM) without SF. Moreover, the devitrification-induced recrystallization/growth of ice during the thawing process is suppressed. Most importantly, the addition of 10 mg mL-1 SF can achieve 81.28% cell viability of cryopreserved hBMSCs as similar as those with the addition of 180 mg mL-1 Ficoll 70 (commercial CPA), and the functions of the cryopreserved hBMSCs are maintained as good as that of the fresh ones. This work is not only significant for meeting the ever-increasing demand of cell therapy, but also trailblazing for designing materials in controlling ice formation and growth during the CP of other cells and tissues.

8.
Clin Biomech (Bristol, Avon) ; 88: 105419, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34303068

RESUMO

BACKGROUND: Pelvic incidence is the quantification of the pelvis anatomical shape which has significant effect on the occurrence of various lumbar degenerative diseases. The aim of this study was to measure the in vivo dynamic motion characteristics of the lower lumbar spine in people with different pelvic incidence. METHODS: A total of 55 volunteers were included in the study. The participants were devided into 3 groups (A: pelvic incidence≤40°, B: 40° < pelvic incidence <60° and C: pelvic incidence ≥60°). The L3-S1 vertebrae of each subject was MRI scanned to construct 3D models. The lumbar spine was then imaged using a dual fluoroscopic imaging system as the subject performed physiological position. The 3D vertebral models and the fluoroscopic images were used to reproduce the in vivo vertebral positions along the motion path. The relative translations and rotations of each motion segment were analyzed. FINDINGS: At the L5-S1 segment, the primary ranges of motion for left-right axial rotation and flexion-extension of the patients with large pelvic incidence (3.28° ± 0.79°, 7.56° ± 1.81°) were significantly larger than normal pelvic incidence (2.61° ± 1.01°, 6.57° ± 2.18°) and small pelvic incidence (2.00° ± 0.60°, 5.83° ± 1.67°). INTERPRETATION: The anatomic variable pelvic incidence is associated with the ranges of motion in lower lumbar vertebrae, especially in the L4-5 and L5-S1 segments.

9.
Molecules ; 26(13)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206838

RESUMO

Polyphenols, widely distributed in the genus Melastoma plants, possess extensive cellular protective effects such as anti-inflammatory, anti-tyrosinase, and anti-obesity, which makes it a potential anti-inflammatory drug or enzyme inhibitor. Therefore, the aim of this study is to screen for the anti-inflammatory and enzyme inhibitory activities of compounds from title plant. Using silica gel, MCI, ODS C18, and Sephadex LH-20 column chromatography, as well as semipreparative HPLC, the extract of Melastoma normale roots was separated. Four new ellagitannins, Whiskey tannin C (1), 1-O-(4-methoxygalloyl)-6-O-galloyl-2,3-O-(S)-hexahydroxydiphenoyl-ß-d-glucose (2), 1-O-galloyl-6-O-(3-methoxygalloyl)-2,3-O-(S)-hexahydroxydiphenoyl-ß-d-glucose (3), and 1-O-galloyl-6-O-vanilloyl-2,3-O-(S)-hexahydroxydiphenoyl-ß-d-glucose (4), along with eight known polyphenols were firstly obtained from this plant. The structures of all isolates were elucidated by HRMS, NMR, and CD analyses. Using lipopolysaccharide (LPS)-stimulated RAW2 64.7 cells, we investigated the anti-inflammatory activities of compounds 1-4, unfortunately, none of them exhibit inhibit nitric oxide (NO) production, their IC50 values are all > 50 µM. Anti-tyrosinase activity assays was done by tyrosinase inhibition activity screening model. Compound 1 showed weak tyrosinase inhibitory activity with IC50 values of 426.02 ± 11.31 µM. Compounds 2-4 displayed moderate tyrosinase inhibitory activities with IC50 values in the range of 124.74 ± 3.12-241.41 ± 6.23 µM. The structure-activity relationships indicate that hydroxylation at C-3', C-4', and C-3 in the flavones were key to their anti-tyrosinase activities. The successful isolation and structure identification of ellagitannin provide materials for the screening of anti-inflammatory drugs and enzyme inhibitors, and also contribute to the development and utilization of M. normale.


Assuntos
Anti-Inflamatórios/análise , Inibidores Enzimáticos/farmacologia , Taninos Hidrolisáveis/análise , Melastomataceae/química , Monofenol Mono-Oxigenase/antagonistas & inibidores , Extratos Vegetais/química , Polifenóis/farmacologia , Animais , Anti-Inflamatórios/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Concentração Inibidora 50 , Camundongos , Estrutura Molecular , Óxido Nítrico/metabolismo , Extratos Vegetais/análise , Polifenóis/química , Células RAW 264.7
10.
Plant J ; 107(2): 467-479, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33942410

RESUMO

Association of RNA polymerase V (Pol V) with chromatin is a critical step for RNA- directed DNA methylation (RdDM) in plants. Although the methylated DNA-binding proteins SUVH2 and SUVH9 and the chromatin remodeler-containing complex DRD1-DMS3-RDM1 are known to be required for the association of Pol V with chromatin, the molecular mechanisms underlying the association of Pol V with different chromatin environments remain largely unknown. Here we found that SUVH9 interacts with FVE, a homolog of the mammalian retinoblastoma-associated protein, which has been previously identified as a shared subunit of the histone deacetylase complex and the polycomb-type histone H3K27 trimethyltransferase complex. We demonstrated that FVE facilitates the association of Pol V with chromatin and thus contributes to DNA methylation at a substantial subset of RdDM target loci. Compared with FVE-independent RdDM target loci, FVE-dependent RdDM target loci are more abundant in gene-rich chromosome arms than in pericentromeric heterochromatin regions. This study contributes to our understanding of how the association of Pol V with chromatin is regulated in different chromatin environments.

11.
Anal Bioanal Chem ; 413(15): 3847-3859, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33934191

RESUMO

Graphdiyne (GDY) adsorbed DNA probes have been used as a fluorescent sensing platform, but topics including DNA adsorption affinities, DNA probe displacement, and fluorescence quenching ability were rarely researched. Herein, the adsorption affinity of single-stranded DNA (ssDNA) and double-stranded DNA (dsDNA) on a tremella-like GDY was tuned by modulating the surface chemistry of GDY. The fluorescence quenching ability of GDY with different oxidation degrees was compared. The nonspecific displacement of DNA probes on GDY was studied. Under the same concentrations, GDY with low oxidation degree exhibited stronger adsorption affinity and higher adsorption capacity to both ssDNA and dsDNA than highly oxidized GDY. DNA adsorbed on low-oxidized GDY was more resistant to displacement by other DNAs. Protein showed strong interaction with different GDY and could displace DNA probes on GDY. Based on these findings, an ideal GDY with proper oxidation degree, exhibiting high surface affinity for ssDNA and low affinity for dsDNA, was used as scavenger of redundant ssDNA fluorescent probe in an enzyme-assisted amplification system for sensitive ochratoxin (OTA) detection. This study has enhanced our fundamental understanding of DNA adsorption by GDY. It also provided a rational way to apply GDY for fluorescence sensing in a complicated system.


Assuntos
DNA/química , Grafite/química , Espectrometria de Fluorescência/métodos , Adsorção , Corantes Fluorescentes/química , Limite de Detecção , Microscopia Eletrônica de Varredura , Ocratoxinas/análise , Análise Espectral/métodos , Propriedades de Superfície
12.
Anal Chem ; 93(19): 7292-7299, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-33956419

RESUMO

Herein, we proposed an innovative visual quantitative sensing strategy based on thiol-ene click chemistry and the capillary action principle. A triethoxyvinylsilane (VTEO)- or mercaptopropylsilatrane (MPS)-modified interface was prepared for analyte recognition. Target analyte molecules containing thiol groups or C═C double bonds are coupled to the VTEO- or MPS-modified inner surface of the glass capillary tube via a thiol-ene click reaction, respectively. Then, the molecular recognition events were transformed into the wettability change of the inner wall of the glass capillary. The concentration of the target molecules was quantified by reading the height change of the water column in the capillary tube. As a proof of concept, this strategy was successfully used to build visual quantitative sensors for detecting glutathione and cholesterol. In addition, this strategy showed a good anti-interference ability to complex biological fluids and realized sensitive glutathione (GSH) and cholesterol detection in real human blood samples.


Assuntos
Glutationa , Compostos de Sulfidrila , Colesterol , Química Click , Humanos , Molhabilidade
13.
Biomacromolecules ; 22(6): 2614-2624, 2021 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-33945264

RESUMO

Antifreeze (glyco)proteins (AF(G)Ps) are naturally evolved ice inhibitors incomparable to any man-made materials, thus, they are gaining intensive interest for cryopreservation and beyond. AF(G)Ps depress the freezing temperature (Tf) noncolligatively below the melting temperature (Tm), generating a thermal hysteresis (TH) gap, within which the ice growth is arrested. However, the ice crystals have been reported to undergo a retaliatory and explosive growth beyond the TH gap, which is lethal to living organisms. Although intensive research has been carried to inhibit such an explosive ice growth, no satisfactory strategy has been discovered until now. Here, we report that crowded solutions mimicking an extracellular matrix (ECM), in which AF(G)Ps are located, can completely inhibit the explosive ice growth. The crowded solutions are the condensates of liquid-liquid phase separation consisting of polyethylene glycol (PEG) and sodium citrate (SC), which possess a nanoscale network and strong hydrogen bond (HB) forming ability, completely different to crowded solutions made of single components, that is, PEG or SC. Due to these unique features, the dynamics of the water is significantly slowed down, and the energy needed for breaking the HB between water molecules is distinctly increased; consequently, ice growth is inhibited as the rate of water molecules joining the ice is substantially reduced. The present work not only opens a new avenue for cryopreservation, but also suggests that the ECM of cold-hardy organisms, which also exhibit great water confining properties, may have a positive effect in protecting the living organisms from freezing damage.


Assuntos
Substâncias Explosivas , Gelo , Proteínas Anticongelantes , Crioprotetores/farmacologia , Congelamento , Humanos
14.
Angew Chem Int Ed Engl ; 60(27): 15049-15053, 2021 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-33872455

RESUMO

Triphenylphosphine (TPP)-based luminescent compounds are rarely investigated because of the low photoluminescence quantum yield (PLQY). Here, we demonstrate that introducing steric hindrance groups to the TPP moiety and separating the orbitals involved in the transition can drastically suppress the non-radiative decay induced by structural distortion of TPP in the excited state. High PLQY up to 0.89 as well as thermally activated delayed fluorescence are observed from the intramolecular charge-transfer (ICT) molecules with substituted TPP donors (sTPPs) in doped films. The red organic light-emitting diodes employing these emitters achieve comparable external quantum efficiencies to the control device containing a classical phosphorescent dye, revealing the great potential of the ICT emitters based on electrochemically stable sTPPs.

15.
Clin Epigenetics ; 13(1): 87, 2021 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-33883002

RESUMO

Diabetic kidney disease (DKD) is one of the most common microvascular complication of both type 1 (T1DM) and type 2 diabetes mellitus (T2DM), and the leading cause of end-stage renal disease (ESRD) worldwide. Persistent inflammation and subsequent chronic fibrosis are major causes of loss of renal function, which is associated with the progression of DKD to ESRD. In fact, DKD progression is affected by a combination of genetic and environmental factors. Approximately, one-third of diabetic patients progress to develop DKD despite intensive glycemic control, which propose an essential concept "metabolic memory." Epigenetic modifications, an extensively studied mechanism of metabolic memory, have been shown to contribute to the susceptibility to develop DKD. Epigenetic modifications also play a regulatory role in the interactions between the genes and the environmental factors. The epigenetic contributions to the processes of inflammation and fibrogenesis involved in DKD occur at different regulatory levels, including DNA methylation, histone modification and non-coding RNA modulation. Compared with genetic factors, epigenetics represents a new therapeutic frontier in understanding the development DKD and may lead to therapeutic breakthroughs due to the possibility to reverse these modifications therapeutically. Early recognition of epigenetic events and biomarkers is crucial for timely diagnosis and intervention of DKD, and for the prevention of the progression of DKD to ESRD. Herein, we will review the latest epigenetic mechanisms involved in the renal pathology of both type 1 (T1DN) and type 2 diabetic nephropathy (T2DN) and highlight the emerging role and possible therapeutic strategies based on the understanding of the role of epigenetics in DKD-associated inflammation and fibrogenesis.

16.
World J Pediatr ; 17(2): 152-163, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33829387

RESUMO

INTRODUCTION: The efficacy of inhaled budesonide for managing moderate-to-severe acute exacerbations in children is not clear. Therefore, this study aimed to evaluate hospital admission rates, need for use of systemic corticosteroids, length of hospital stay and adverse events when inhaled budesonide is added to standard pediatric emergency department management of moderate-to-severe acute exacerbations of asthma. METHODS: A systematic search was conducted in PubMed, Scopus, CENTRAL (Cochrane Central Register of Controlled Trials) and Google scholar databases. Randomized controlled trials that evaluated the effect of nebulized budesonide in moderate-to-severe acute exacerbations of asthma in pediatric patients were included for this meta-analysis. Statistical analysis was done using STATA version 13.0. RESULTS: A total of 16 RCTs were included. Children receiving nebulized budesonide had 43% lower risk of being hospitalized (RR 0.57; 95% CI, 0.39; 0.85) and 66% lower risk of requiring systemic corticosteroids (RR 0.34; 95 % CI, 0.21; 0.55) compared with those receiving placebo. There were no differences in the length of hospital stay (Hedges's g standardized mean difference - 1.53; 95% CI, - 3.64; 0.58) and risk of adverse events (RR 0.87, 95% CI; 0.65; 1.17) between the two groups. There was no evidence of publication bias for any of the outcomes considered. CONCLUSION: The findings of this meta-analysis support the use of inhaled budesonide in reducing risk of hospitalization and the need for systemic corticosteroids among children with acute moderate-to-severe asthma exacerbation.

17.
Biosens Bioelectron ; 181: 113152, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33725504

RESUMO

Photocathode-based assay is anti-interference for real sample detection. Photocathode produces low photocurrent signal and gives rise to poor sensitivity. Herein, a novel cathode photoelectrochemical (CPEC) sensing platform based on Ag-AgI-CNTs as photocathode material and K3[Fe(CN)6] as photoelectron acceptor was established. Since [Fe(CN)6]3- effectively accepted photoelectrons from Ag-AgI-CNTs, it greatly enhanced the CPEC response. Combining a surface multisite strand displacement amplification (SMSDA) strategy, the CPEC platform was applied for the activity assay of terminal deoxynucleotidyl transferase (TdT). In this proposal, oligo dT primer tethered on CPEC platform was in-situ extended to generate a polyA tail. Then the polyA tail formed a stable multi-point hybrid structure with the adjacent oligo dT. After launching the SMSDA, the CPEC platform was covered by more elongated polynucleotide chains and network, which acutely hampered the photoelectron transfer (eT) between photocathode and electron acceptor and caused a reduced photocurrent. The CPEC sensor possessed a satisfactory linear response from 6 × 10-5-0.1 U and a low detection limit of 1.1 × 10-5 U. The strategy offered a more specific and sensitive method for TdT activity assay. It was feasible in the field of TdT-based biochemical research, drug screening, and disease diagnosis.


Assuntos
Técnicas Biossensoriais , DNA Nucleotidilexotransferase , Eletrodos , Prata
18.
Nanotechnology ; 2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33765675

RESUMO

A novel preparation process has been developed to synthesize MgH2nanoparticles by combining ball milling and thermal hydrogenolysis of di-n-butylmagnesium (C4H9)2Mg, denoted as MgBu2). With the aid of mechanical impact and the dispersant, the hydrogenolysis temperature of MgBu2in heptane solution was considerably lowered down to 100 ºC, and the MgH2nanoparticles with an average particle size ofca.8.9 nm were obtained without scaffolds. The nano-size effect of the MgH2nanoparticles causes a significant decrease in the onset dehydrogenation temperature of 225 ºC and enthalpy of 69.78 kJ/mol∙H2. This thermally-assisted milling and hydrogenolysis process may also be extended for synthesizing other nanoscale hydrides and catalysts.

19.
J Diabetes Res ; 2021: 3170190, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33553435

RESUMO

Methods: In this multicenter retrospective study, patients with COVID-19 in China were included and classified into two groups according to whether they were complicated with diabetes or not. Demographic symptoms and laboratory data were extracted from medical records. Univariable and multivariable logistic regression methods were used to explore the risk factors. Results: 538 COVID-19 patients were finally included in this study, of whom 492 were nondiabetes and 46 were diabetes. The median age was 47 years (IQR 35.0-56.0). And the elderly patients with diabetes were more likely to have dry cough, and the alanine aminotransferase, lactate dehydrogenase, Ca, and mean hemoglobin recovery rate were higher than the other groups. Furthermore, we also found the liver and kidney function of male patients was worse than that of female patients, while female cases should be paid more attention to the occurrence of bleeding and electrolyte disorders. Moreover, advance age, blood glucose, gender, prothrombin time, and total cholesterol could be considered as risk factors for COVID-19 patients with diabetes through the multivariable logistic regression model in our study. Conclusion: The potential risk factors found in our study showed a major piece of the complex puzzle linking diabetes and COVID-19 infection. Meanwhile, focusing on gender and age factors in COVID-19 patients with or without diabetes, specific clinical characteristics, and risk factors should be paid more attention by clinicians to figure out a targeted intervention to improve clinical efficacy worldwide.


Assuntos
COVID-19/complicações , Diabetes Mellitus Tipo 1/complicações , Diabetes Mellitus Tipo 2/complicações , Hospitalização , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais
20.
J Biol Chem ; 296: 100300, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33460648

RESUMO

Acetaminophen (APAP)-induced liver necrosis is a form of regulated cell death (RCD) in which APAP activates the mitogen-activated protein kinases (MAPKs) and specifically the c-Jun-N-terminal kinase (JNK) pathway, leading to necrotic cell death. Previously, we have shown that receptor interacting protein kinase-1 (RIPK1) knockdown is also protective against APAP RCD upstream of JNK. However, whether the kinase or platform function of RIPK1 is involved in APAP RCD is not known. To answer this question, we used genetic mouse models of targeted hepatocyte RIPK1 knockout (RIPK1HepCKO) or kinase dead knock-in (RIPK1D138N) and adult hepatocyte specific knockout of the cytoprotective protein A20 (A20HepCKO), known to interact with RIPK1, to study its potential involvement in MAPK signaling. We observed no difference in injury between WT and RIPK1D138N mice post APAP. However, RIPK1HepCKO was protective. We found that RIPK1HepCKO mice had attenuated pJNK activation, while A20 was simultaneously upregulated. Conversely, A20HepCKO markedly worsened liver injury from APAP. Mechanistically, we observed a significant upregulation of apoptosis signal-regulating kinase 1 (ASK1) and increased JNK activation in A20HepCKO mice compared with littermate controls. We also demonstrated that A20 coimmunoprecipitated (co-IP) with both RIPK1 and ASK1, and that in the presence of RIPK1, there was less A20-ASK1 association than in its absence. We conclude that the kinase-independent platform function of RIPK1 is involved in APAP toxicity. Adult RIPK1HepCKO mice are protected against APAP by upregulating A20 and attenuating JNK signaling through ASK1, conversely, A20HepCKO worsens injury from APAP.


Assuntos
Acetaminofen/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/genética , MAP Quinase Quinase Quinase 5/genética , Sistema de Sinalização das MAP Quinases/genética , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Regulação da Expressão Gênica , Hepatócitos/metabolismo , Hepatócitos/patologia , Fígado/metabolismo , Fígado/patologia , MAP Quinase Quinase 4/genética , MAP Quinase Quinase 4/metabolismo , MAP Quinase Quinase Quinase 5/metabolismo , Masculino , Camundongos , Camundongos Transgênicos , Ligação Proteica , Proteína Serina-Treonina Quinases de Interação com Receptores/deficiência , Índice de Gravidade de Doença , Proteína 3 Induzida por Fator de Necrose Tumoral alfa/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...