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1.
Mater Horiz ; 11(9): 2115-2130, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38623069

RESUMO

Vacancies, as well as their derivatives, usually play a crucial role in many essential properties of materials. However, they always behave erratically, especially under universal thermal vibration, and are therefore difficult to accurately locate. Until now, the lack of an accurate and flexible method for locating and identifying vacancies has hampered the development of relative fields. In this paper, we present a new method to solve this problem. The strategy is to target the atomic cage enwrapping vacancies instead of the vacancies themselves. The core of the method is a time-averaged atomic volume spectrum (TAVS). The key to this method is to identify atoms using time-averaged rather than transient atomic volume, thereby simultaneously denoising intrinsic thermal vibration and avoiding vacancy migration jump. Using this method, we have succeeded for the first time in obtaining the panoramic maps of spontaneously trapped defects in quenched and annealed face-centered cubic aluminum and even the instantaneous images of a steady trapping process. All characteristics of each trapped vacancy, including location, dimension, volume and morphology, as well as aggregate statistical data such as vacancy amount and concentration, can be completely and accurately obtained. Furthermore, these first maps of defects (vacancies) revealed some surprising and interesting phenomena for future exploration. In conclusion, this method provides not only a means of locating and catching vacancies, but also a strategy for identifying and characterizing vacancies. On the basis of its successful application in FCC Al, the TAVS method can be easily extended to other systems as well.

2.
Open Med (Wars) ; 19(1): 20230894, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38645437

RESUMO

Objective: In this article, the epidemiology, molecular mechanism of occurrence and development, risk factors, and treatment of diabetic microvascular complications such as diabetic nephropathy, diabetic retinopathy, and diabetic peripheral neuropathy were discussed, providing the theoretical basis for more accurate elucidation of the pathogenesis and treatment of diabetic microvascular complications. Methods: The electronic database of PubMed was searched, and retrieved papers were screened for eligibility by two independent reviewers. Data were extracted using a standardized data extraction form and the quality of included papers was assessed. Results: Thirty-eight articles were included. Diabetes nephropathy, diabetes peripheral neuropathy, and diabetes retinopathy are the most common and serious microvascular complications of diabetes in clinical patients. Renin-angiotensin system blockers, beta drugs, statins, antivascular endothelial growth factor drugs, and antioxidants can inhibit the occurrence of microvascular complications in diabetes. Conclusions: However, there has been no breakthrough in the treatment of diabetic microvascular complications. Therefore, prevention of diabetic microvascular complications is more important than treatment.

3.
Angew Chem Int Ed Engl ; : e202403980, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38588065

RESUMO

Electrochemical reduction of CO2 and nitrate offers a promising avenue to produce valuable chemicals through the using of greenhouse gas and nitrogen-containing wastewater. However, the generally proposed reaction pathway of concurrent CO2 and nitrate reduction for urea synthesis requires the catalysts to be both efficient in both CO2 and nitrate reduction, thus narrowing the selection range of suitable catalysts. Herein, we demonstrate a distinct mechanism in urea synthesis, a tandem NO3 - and CO2 reduction, in which the surface amino species generated by nitrate reduction play the role to capture free CO2 and subsequent initiate its activation. When using the TiO2 electrocatalyst derived from MIL-125-NH2, it intrinsically exhibits low activity in aqueous CO2 reduction, however, in the presence of both nitrate and CO2, this catalyst achieves an excellent urea yield rate of 43.37 mmol ⋅ g-1 ⋅ h-1 and a Faradaic efficiency of 48.88 % at -0.9 V vs. RHE in a flow cell. Even at a low CO2 level of 15 %, the Faradaic efficiency of urea synthesis remains robust at 42.33 %. The tandem reduction procedure was further confirmed by in situ spectroscopies and theoretical calculations. This research provides new insights into the selection and design of electrocatalysts for urea synthesis.

4.
Sci Transl Med ; 16(737): eabm2090, 2024 03 06.
Artigo em Inglês | MEDLINE | ID: mdl-38446901

RESUMO

Diabetic kidney disease (DKD) is the main cause of chronic kidney disease (CKD) and progresses faster in males than in females. We identify sex-based differences in kidney metabolism and in the blood metabolome of male and female individuals with diabetes. Primary human proximal tubular epithelial cells (PTECs) from healthy males displayed increased mitochondrial respiration, oxidative stress, apoptosis, and greater injury when exposed to high glucose compared with PTECs from healthy females. Male human PTECs showed increased glucose and glutamine fluxes to the TCA cycle, whereas female human PTECs showed increased pyruvate content. The male human PTEC phenotype was enhanced by dihydrotestosterone and mediated by the transcription factor HNF4A and histone demethylase KDM6A. In mice where sex chromosomes either matched or did not match gonadal sex, male gonadal sex contributed to the kidney metabolism differences between males and females. A blood metabolomics analysis in a cohort of adolescents with or without diabetes showed increased TCA cycle metabolites in males. In a second cohort of adults with diabetes, females without DKD had higher serum pyruvate concentrations than did males with or without DKD. Serum pyruvate concentrations positively correlated with the estimated glomerular filtration rate, a measure of kidney function, and negatively correlated with all-cause mortality in this cohort. In a third cohort of adults with CKD, male sex and diabetes were associated with increased plasma TCA cycle metabolites, which correlated with all-cause mortality. These findings suggest that differences in male and female kidney metabolism may contribute to sex-dependent outcomes in DKD.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Insuficiência Renal Crônica , Adolescente , Adulto , Humanos , Feminino , Masculino , Animais , Camundongos , Caracteres Sexuais , Piruvatos , Glucose , Rim
5.
Int J Mol Sci ; 25(4)2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38396797

RESUMO

Pluripotent stem cells (PSCs) can differentiate into three germ layers and diverse autologous cell lines. Since cattle are the most commonly used large domesticated animals, an important food source, and bioreactors, great efforts have been made to establish bovine PSCs (bPSCs). bPSCs have great potential in bovine breeding and reproduction, modeling in vitro differentiation, imitating cancer development, and modeling diseases. Currently, bPSCs mainly include bovine embryonic stem cells (bESCs), bovine induced pluripotent stem cells (biPSCs), and bovine expanded potential stem cells (bEPSCs). Establishing stable bPSCs in vitro is a critical scientific challenge, and researchers have made numerous efforts to this end. In this review, the category of PSC pluripotency; the establishment of bESCs, biPSCs, and bEPSCs and its challenges; and the application outlook of bPSCs are discussed, aiming to provide references for future research.


Assuntos
Células-Tronco Pluripotentes Induzidas , Células-Tronco Pluripotentes , Bovinos , Animais , Células-Tronco Pluripotentes/metabolismo , Diferenciação Celular , Células-Tronco Embrionárias
6.
Int J Biol Macromol ; 259(Pt 2): 129337, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38218296

RESUMO

Mitochondrial autophagy (mitophagy) is a key physiological process that maintains the homeostasis of mitochondrial quality and quantity. Monitoring mitophagy is of great significance for detecting cellular abnormalities and developing therapeutic drugs. However, there are still very few biomarkers specifically developed for monitoring mitophagy. Here, we propose for the first time that mitochondrial G-quadruplex may serve as a biomarker for mitophagy detection, and develope a fluorescent light-up probe AMTC to monitor mitophagy in live cells. During mitophagy, AMTC fluorescence is significantly enhanced, but once mitophagy is inhibited, its fluorescence immediately decreases. The fluorescence behavior of AMTC implicates an increase in the formation of mitochondrial G-quadruplex during mitophagy. This inference has also been supported by the other two G-quadruplex probes. Taken together, this work provides a new possible biomarker and detection tool for the study of mitophagy.


Assuntos
Mitocôndrias , Mitofagia , Autofagia , Microscopia de Fluorescência , Biomarcadores
7.
J Am Chem Soc ; 146(6): 4068-4077, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38289263

RESUMO

The synthesis of photocatalysts with both broad light absorption and efficient charge separation is significant for a high solar energy conversion, which still remains to be a challenge. Herein, a narrow-bandgap Y2Ti2O5S2 (YTOS) oxysulfide nanosheet coexposed with defined {101} and {001} facets synthesized by a flux-assisted solid-state reaction was revealed to display the character of an anisotropic charge migration. The selective photodeposition of cocatalysts demonstrated that the {101} and {001} surfaces of YTOS nanosheets were the reduction and oxidation regions during photocatalysis, respectively. Density functional theory (DFT) calculations indicated a band energy level difference between the {101} and {001} facets of YTOS, which contributes to the anisotropic charge migration between them. The exposed Ti atoms on the {101} surface and S atoms on the {001} surface were identified, respectively, as reducing and oxidizing centers of YTOS nanosheets. This anisotropic charge migration generated a built-in electric field between these two facets, quantified by spatially resolved surface photovoltage microscopy, the intensity of which was found to be highly correlated with photocatalytic H2 production activity of YTOS, especially exhibiting a high apparent quantum yield of 18.2% (420 nm) after on-site modification of a Pt@Au cocatalyst assisted by Na2S-Na2SO3 hole scavengers. In conjunction with an oxygen-production photocatalyst and a [Co(bpy)3]2+/3+ redox shuttle, the YTOS nanosheets achieved a solar-to-hydrogen conversion efficiency of 0.15% via a Z-scheme overall water splitting. Our work is the first to confirm anisotropic charge migration in a perovskite oxysulfide photocatalyst, which is crucial for enhancing charge separation and surface catalytic efficiency in this material.

8.
Sci Rep ; 13(1): 21305, 2023 12 02.
Artigo em Inglês | MEDLINE | ID: mdl-38042941

RESUMO

Methane (CH4) emissions from ruminants are of a significant environmental concern, necessitating accurate prediction for emission inventories. Existing models rely solely on dietary and host animal-related data, ignoring the predicting power of rumen microbiota, the source of CH4. To address this limitation, we developed novel CH4 prediction models incorporating rumen microbes as predictors, alongside animal- and feed-related predictors using four statistical/machine learning (ML) methods. These include random forest combined with boosting (RF-B), least absolute shrinkage and selection operator (LASSO), generalized linear mixed model with LASSO (glmmLasso), and smoothly clipped absolute deviation (SCAD) implemented on linear mixed models. With a sheep dataset (218 observations) of both animal data and rumen microbiota data (relative sequence abundance of 330 genera of rumen bacteria, archaea, protozoa, and fungi), we developed linear mixed models to predict CH4 production (g CH4/animal·d, ANIM-B models) and CH4 yield (g CH4/kg of dry matter intake, DMI-B models). We also developed models solely based on animal-related data. Prediction performance was evaluated 200 times with random data splits, while fitting performance was assessed without data splitting. The inclusion of microbial predictors improved the models, as indicated by decreased root mean square prediction error (RMSPE) and mean absolute error (MAE), and increased Lin's concordance correlation coefficient (CCC). Both glmmLasso and SCAD reduced the Akaike information criterion (AIC) and Bayesian information criterion (BIC) for both the ANIM-B and the DMI-B models, while the other two ML methods had mixed outcomes. By balancing prediction performance and fitting performance, we obtained one ANIM-B model (containing 10 genera of bacteria and 3 animal data) fitted using glmmLasso and one DMI-B model (5 genera of bacteria and 1 animal datum) fitted using SCAD. This study highlights the importance of incorporating rumen microbiota data in CH4 prediction models to enhance accuracy and robustness. Additionally, ML methods facilitate the selection of microbial predictors from high-dimensional metataxonomic data of the rumen microbiota without overfitting. Moreover, the identified microbial predictors can serve as biomarkers of CH4 emissions from sheep, providing valuable insights for future research and mitigation strategies.


Assuntos
Metano , Rúmen , Ovinos , Animais , Feminino , Teorema de Bayes , Ruminantes , Dieta/veterinária , Bactérias/genética , Ração Animal/análise , Lactação
9.
Am J Nucl Med Mol Imaging ; 13(5): 195-207, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38023815

RESUMO

Radiotracers and medical imaging equipment are the two main keys to molecular imaging. While radiotracers are of great interest to research and industry, medical imaging equipment technology is blossoming everywhere. Total-body PET/CT (TB-PET/CT) has emerged in response to this trend and is rapidly gaining traction in the fields of clinical oncology, cardiovascular medicine, inflammatory/infectious diseases, and pediatric diseases. In addition, the use of a growing number of radiopharmaceuticals in TB-PET/CT systems has shown promising results. Notably, the distinctive features of TB-PET/CT, such as its ultra-long axial field of view (194 cm), ultra-high sensitivity, and capability for low-dose tracer imaging, have enabled enhanced imaging quality while reducing the radiation dose. The envisioned whole-body dynamic imaging, delayed imaging, personalized disease management, and ultrafast acquisition for motion correction, among others, are achieved. This review highlights two key factors affecting molecular imaging, describing the rapid imaging effects of radiotracers allowed at low doses on TB-PET/CT and the improvements offered compared to conventional PET/CT.

10.
Stud Health Technol Inform ; 308: 437-444, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-38007770

RESUMO

Oxaliplatin, as previously studied in the paper, is a derivative of Cisplatin that is effective in treating the Lewis Lung Carcinoma (LLC)4. As it can actively induce immunogenic cell death of the cancer cells, and result in apoptosis, which increases the therapeutic efficacy in the LLC cancer treatment.4 Merkel cell caner is a type of skin cancer that is rare but highly aggressive, with high metastasizing and reoccurring rate. In this study, we aim the determine the potential of Oxaliplatin to induce apoptosis and ICD in cancerous Merkel cell line MCC1, in associate with the PD-1 inhibitor Nivolumab. The cancer cells will be treated with Oxaliplatin at concentrations 1 mM, 10 mM, or 100 mM. Avelumab and PBS will be used as the positive and negative control, respectively. The treated cells will be measured by checking for tumor size change in confocal microscopy and MTT assay, measuring the ICD using flow cytometry analysis of CRT expression, and conducting Western Blot for Cytokeratin 20 expression. The results of the study will provide insights on the potential of Oxaliplatin as a treatment of Merkel Cell Cancer in the future.


Assuntos
Carcinoma de Célula de Merkel , Neoplasias Cutâneas , Humanos , Oxaliplatina/farmacologia , Oxaliplatina/uso terapêutico , Carcinoma de Célula de Merkel/tratamento farmacológico , Carcinoma de Célula de Merkel/patologia , Células de Merkel/patologia , Morte Celular Imunogênica , Apoptose , Neoplasias Cutâneas/tratamento farmacológico , Linhagem Celular Tumoral
11.
Environ Sci Pollut Res Int ; 30(51): 110995-111007, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37798525

RESUMO

Conduction between the unique geological formation karst collapse pillar (KCP) and the fractures caused by mining in the coal seam floor can lead to catastrophic water inrush disasters in many coalmines in Northern China. It is widely recognized that seepage mutation induced by the migration/loss of KCP fillings (highly broken rocks filling the fractured rocks) happens during occurrence of the KCP-related water inrush. However, roles of fluid path (mining-induced fracture) scale and KCP filling porosity in seepage mutation evolution remain unclear. Here, we conducted seepage tests on natural KCP fillings containing rock particles of different sizes. The filling specimens were deformed to different porosities from 14 to 26% through axial compression, and small to large fluid paths were simulated by seepage plates with distinct pore sizes from 2.5 to 12.5 mm. We found that seepage mutation occurs with significant permeability enhancement by 2 orders of magnitude under a pore diameter of 12.5 mm and a specimen porosity of 26%. There is a strong linear relationship between specimen permeability and Reynolds number (Re) over seepage mutation. The mutation is caused by the sudden collapse of the specimen skeleton and subsequent quick outflow of the particles. Therefore, it is inferred that the KCP-related water inrush is more likely to happen when highly porous KCP fillings are present and mining-induced fractures are well developed.


Assuntos
Mineração , Água , China , Carvão Mineral/análise , Permeabilidade
12.
Adv Healthc Mater ; 12(32): e2301428, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37830445

RESUMO

The early-stage placental barrier is characterized by a lack of fetal circulation and by a thick trophoblastic barrier, whereas the later-stage placenta consists of vascularized chorionic villi encased in a thin, differentiated trophoblast layer, ideal for nutrient transport. In this work, predictive models of early- and late-stage placental transport are created using blastocyst-derived placental stem cells (PSCs) by modulating PSC differentiation and model vascularization. PSC differentiation results in a thinner, fused trophoblast layer, as well as an increase in human chorionic gonadotropin secretion, barrier permeability, and secretion of certain inflammatory cytokines, which are consistent with in vivo findings. Further, gene expression confirms this shift toward a differentiated trophoblast subtype. Vascularization results in a molecule type- and size-dependent change in dextran and insulin permeability. These results demonstrate that trophoblast differentiation and vascularization have critical effects on placental barrier permeability and that this model can be used as a predictive measure to assess fetal toxicity of xenobiotic substances at different stages of pregnancy.


Assuntos
Placenta , Trofoblastos , Gravidez , Feminino , Humanos , Trofoblastos/metabolismo , Diferenciação Celular , Vilosidades Coriônicas/metabolismo , Células-Tronco
13.
ACS Appl Mater Interfaces ; 15(40): 47754-47763, 2023 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-37769117

RESUMO

Solar water splitting from a p-n-conjugated photoelectrochemical (PEC) system is a promising way to produce hydrogen sustainably. At present, finding a compatible p-type photocathode material for the p-n system remains a great challenge in consideration of the photocurrent and stability. This paper highlighted a promising candidate, Rh/BaTiO3, by switching BaTiO3 from an n-type photoanode to a p-type photocathode upon Rh doping. The dopant activated visible light absorption up to 550 nm and an onset potential as high as 1.0 V (vs RHE). Using surface photovoltage spectroscopy as a powerful characterization tool, the n- to p-type transition of the semiconductor was studied and explained microscopically by which we quantitatively isolated the cathodic contribution caused by the Rh dopant. Unbiased overall solar water splitting was accomplished by serially connecting the Pt/Rh/BaTiO3 photocathode to a CoOx/Mo/BiVO4 photoanode, which produced a solar to hydrogen conversion efficiency of 0.1% and an excellent stability over 100 h of operation at ambient pressure. This work revealed the key role that the Rh dopant played in the n- to p-type adjustment of titanate semiconductors and demonstrated its great potential for application in PEC water splitting.

14.
Sci Immunol ; 8(87): eadg1487, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37713507

RESUMO

Regulatory T cells (Treg) are conventionally viewed as suppressors of endogenous and therapy-induced antitumor immunity; however, their role in modulating responses to immune checkpoint blockade (ICB) is unclear. In this study, we integrated single-cell RNA-seq/T cell receptor sequencing (TCRseq) of >73,000 tumor-infiltrating Treg (TIL-Treg) from anti-PD-1-treated and treatment-naive non-small cell lung cancers (NSCLC) with single-cell analysis of tumor-associated antigen (TAA)-specific Treg derived from a murine tumor model. We identified 10 subsets of human TIL-Treg, most of which have high concordance with murine TIL-Treg subsets. Only one subset selectively expresses high levels of TNFRSF4 (OX40) and TNFRSF18 (GITR), whose engangement by cognate ligand mediated proliferative programs and NF-κB activation, as well as multiple genes involved in Treg suppression, including LAG3. Functionally, the OX40hiGITRhi subset is the most highly suppressive ex vivo, and its higher representation among total TIL-Treg correlated with resistance to PD-1 blockade. Unexpectedly, in the murine tumor model, we found that virtually all TIL-Treg-expressing T cell receptors that are specific for TAA fully develop a distinct TH1-like signature over a 2-week period after entry into the tumor, down-regulating FoxP3 and up-regulating expression of TBX21 (Tbet), IFNG, and certain proinflammatory granzymes. Transfer learning of a gene score from the murine TAA-specific TH1-like Treg subset to the human single-cell dataset revealed a highly analogous subcluster that was enriched in anti-PD-1-responding tumors. These findings demonstrate that TIL-Treg partition into multiple distinct transcriptionally defined subsets with potentially opposing effects on ICB-induced antitumor immunity and suggest that TAA-specific TIL-Treg may positively contribute to antitumor responses.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Animais , Camundongos , Neoplasias Pulmonares/genética , Granzimas , Transdução de Sinais , Análise de Célula Única
15.
Adv Healthc Mater ; 12(27): e2300423, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37543836

RESUMO

The direction and pattern of fluid flow affect vascular structure and function, in which vessel-lining endothelial cells exhibit variable cellular morphologies and vessel remodeling by mechanosensing. To recapitulate this microenvironment, some approaches have been reported to successfully apply unidirectional flow on endothelial cells in organ-on-a-chip systems. However, these platforms encounter drawbacks such as the dependency on pumps or confinement to closed microfluidic channels. These constraints impede their synergy with advanced biofabrication techniques like 3D bioprinting, thereby curtailing the potential to introduce greater complexity into engineered tissues. Herein, a pumpless recirculating platform (UniPlate) that enables unidirectional media recirculation through 3D printed tubular tissues, is demonstrated.The device is made of polystyrene via injection molding in combination with 3D printed sacrifical gelatin templates. Tubular blood vessels with unidirectional perfusion are firstly engineered. Then the design is expanded to incorporate duo-recirculating flow for culturing vascularized renal proximal tubules with glucose reabsorption function. In addition to media recirculation, human monocyte recirculation in engineered blood vessels is also demonstrated for over 24 h, with minimal loss of cells, cell viability, and inflammatory activation. UniPlate can be a valuable tool to more precisely control the cellular microenvironment of organ-on-a-chip systems for drug discovery.


Assuntos
Células Endoteliais , Microfluídica , Humanos , Perfusão , Microfluídica/métodos , Engenharia Tecidual/métodos , Impressão Tridimensional
16.
Int J Mol Sci ; 24(15)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37569546

RESUMO

Spermatogonial stem cells (SSCs) are the only primitive spermatogonial cells in males that can naturally transmit genetic information to their offspring and replicate throughout their lives. Phospholipase D family member 6 (PLD6) has recently been found to be a surface marker for SSCs in mice and boars; however, it has not been validated in cattle. The results of reversed transcription-polymerase chain reaction (RT-PCR) and quantitative real-time PCR (qRT-PCR) found that the relative expression of the PLD6 gene in the testicular tissues of two-year-old Simmental calves was significantly higher than that of six-month-old calves. Immunofluorescent staining further verified the expression of PLD6 protein in bovine spermatogenic cells like germ cell marker DEAD box helicase 4 (DDX4, also known as VASA). Based on multiple bioinformatic databases, PLD6 is a conservative protein which has high homology with mouse Q5SWZ9 protein. It is closely involved in the normal functioning of the reproductive system. Molecular dynamics simulation analyzed the binding of PLD6 as a phospholipase to cardiolipin (CL), and the PLD6-CL complex showed high stability. The protein interaction network analysis showed that there is a significant relationship between PLD6 and piwi-interacting RNA (piRNA) binding protein. PLD6 acts as an endonuclease and participates in piRNA production. In addition, PLD6 in bovine and mouse testes has a similar expression pattern with the spermatogonium-related genes VASA and piwi like RNA-mediated gene silencing 2 (PIWIL2). In conclusion, these analyses imply that PLD6 has a relatively high expression in bovine testes and could be used as a biomarker for spermatogenic cells including SSCs.

17.
Environ Sci Pollut Res Int ; 30(33): 80416-80431, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37301809

RESUMO

Post-combustion carbon capture is a direct and effective way for onboard carbon capture. Therefore, it is important to develop onboard carbon capture absorbent that can both ensure a high absorption rate and reduce the energy consumption of the desorption process. In this paper, a K2CO3 solution was first established using Aspen Plus to simulate CO2 capture from the exhaust gases of a marine dual-fuel engine in diesel mode. The lean and rich CO2 loading results from the simulation were used to guide the selection and optimization of the activators used in the experiment. During the experiment, five amino acid salt activators including SarK, GlyK, ProK, LysK, and AlaK and four organic amine activators including MEA, PZ, AEEA, and TEPA were used. Experiments only considered the activation effect of CO2 loading between lean and rich conditions. The results showed that after adding a small amount of activator, the absorption rate of CO2 by the absorbent was greatly improved, and the activation effect of organic amine activators was stronger than that of amino acid salts. Among the amino acid salts, the SarK-K2CO3 composite solution showed the best performance in both absorption and desorption. Among the amino acid salts and the organic amino activators, SarK-K2CO3 showed the best performance in strengthening the CO2 desorption while PZ-K2CO3 enhanced the CO2 absorption process the most. In the study of the concentration ratio, it was found that when the mass concentration ratio was 1:1 for SarK:K2CO3 and PZ:K2CO3, the CO2 absorption and desorption processes improved well.


Assuntos
Dióxido de Carbono , Carbono , Dióxido de Carbono/química , Emissões de Veículos , Sais , Gases , Aminas/química , Aminoácidos
18.
J Nanobiotechnology ; 21(1): 182, 2023 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-37280622

RESUMO

Due to its complicated pathophysiology, propensity for metastasis, and poor prognosis, colon cancer is challenging to treat and must be managed with a combination of therapy. Using rolling circle transcription (RCT), this work created a nanosponge therapeutic medication system (AS1411@antimiR-21@Dox). Using the AS1411 aptamer, this approach accomplished targeted delivery to cancer cells. Furthermore, analysis of cell viability, cell apoptosis, cell cycle arrest, reactive oxygen species (ROS) content, and mitochondrial membrane potential (MMP) levels revealed that functional nucleic acid nanosponge drug (FND) can kill cancer cells. Moreover, transcriptomics uncovered a putative mechanism for the FND anti-tumor effect. These pathways, which included mitotic metaphase and anaphase as well as the SMAC-mediated dissociation of the IAP: caspase complexes, were principally linked to the cell cycle and cell death. In conclusion, by triggering cell cycle arrest and apoptosis, the nano-synergistic therapeutic system allowed for the intelligent and effective targeted administration of RNA and chemotherapeutic medicines for colon cancer treatment. The system allowed for payload efficiency while being customizable, targeted, reliable, stable, and affordable.


Assuntos
Aptâmeros de Nucleotídeos , Neoplasias do Colo , Nanopartículas , Ácidos Nucleicos , Humanos , Doxorrubicina/uso terapêutico , Sistemas de Liberação de Medicamentos , Ácidos Nucleicos/uso terapêutico , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/metabolismo , Portadores de Fármacos/uso terapêutico , Aptâmeros de Nucleotídeos/uso terapêutico , Oligodesoxirribonucleotídeos , Nanopartículas/uso terapêutico , Linhagem Celular Tumoral
19.
Lab Chip ; 23(15): 3370-3387, 2023 07 25.
Artigo em Inglês | MEDLINE | ID: mdl-37335565

RESUMO

The colon serves as a primary target for pharmaceutical compound screening and disease modelling. To better study colon diseases and develop treatments, engineered in vitro models with colon-specific physiological features are required. Existing colon models lack integration of colonic crypt structures with underlying perfusable vasculature, where vascular-epithelial crosstalk is affected by disease progression. We present a colon epithelium barrier model with vascularized crypts that recapitulates relevant cytokine gradients in both healthy and inflammatory conditions. Using our previously published IFlowPlate384 platform, we initially imprinted crypt topography and populated the patterned scaffold with colon cells. Proliferative colon cells spontaneously localized to the crypt niche and differentiated into epithelial barriers with a tight brush border. Toxicity of the colon cancer drug, capecitabine, was tested and showed a dose-dependent response and recovery from crypt-patterned colon epithelium exclusively. Perfusable microvasculature was then incorporated around the colon crypts followed by treatment with pro-inflammatory TNFα and IFNγ cytokines to simulate inflammatory bowel disease (IBD)-like conditions. We observed in vivo-like stromal basal-to-apical cytokine gradients in tissues with vascularized crypts and gradient reversals upon inflammation. Taken together, we demonstrated crypt topography integrated with underlying perfusable microvasculature has significant value for emulating colon physiology and in advanced disease modelling.


Assuntos
Colo , Neoplasias do Colo , Humanos , Avaliação Pré-Clínica de Medicamentos , Citocinas , Mucosa Intestinal
20.
Proc Natl Acad Sci U S A ; 120(19): e2212613120, 2023 05 09.
Artigo em Inglês | MEDLINE | ID: mdl-37126714

RESUMO

Oxidative stress is a key feature in both chronic inflammation and cancer. P38 regulated/activated protein kinase (PRAK) deficiency can cause functional disorders in neutrophils and macrophages under high oxidative stress, but the precise mechanisms by which PRAK regulates reactive oxygen species (ROS) elimination and its potential impact on CD4+ T helper subset function are unclear. The present study reveals that the PRAK-NF-E2-related factor 2(NRF2) axis is essential for maintaining the intracellular redox homeostasis of T helper 17(Th17) cells, thereby promoting Th17 cell differentiation and antitumor effects. Through mechanistic analysis, we identify NRF2 as a novel protein substrate of PRAK and find that PRAK enhances the stability of the NRF2 protein through phosphorylation NRF2 Serine(S) 558 independent of protein ubiquitination. High accumulation of cellular ROS caused by loss of PRAK disrupts both glycolysis and PKM2-dependent phosphorylation of STAT3, which subsequently impairs the differentiation of Th17 cells. As a result, Prak knockout (KO) mice display significant resistance to experimental autoimmune encephalomyelitis (EAE) but impaired antitumor immunity in a MC38 tumor model. This work reveals that the PRAK-NRF2-mediated antioxidant pathway is a metabolic checkpoint that controls Th17-cell glycolysis and differentiation. Targeting PRAK is a promising strategy for maintaining an active ROS scavenging system and may lead to potent Th17 cell antitumor immunity.


Assuntos
Encefalomielite Autoimune Experimental , Proteínas Quinases , Animais , Camundongos , Diferenciação Celular , Glicólise , Homeostase , Camundongos Knockout , Fator 2 Relacionado a NF-E2/metabolismo , Oxirredução , Proteínas Quinases/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Células Th17/metabolismo
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