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1.
Ultrason Sonochem ; 106: 106877, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38640683

RESUMO

Lycopene-rich guava (Psidium guajava L.) exhibits significant economic potential as a functional food ingredient, making it highly valuable for the pharmaceutical and agro-food industries. However, there is a need to enhance the extraction methods of lycopene to fully exploit its beneficial uses. In this study, we evaluated various ionic liquids to identify the most effective one for extracting lycopene from guava. Among thirteen ionic liquids with varying carbon chains or anions, 1-butyl-3-methylimidazolium chloride demonstrated the highest productivity. Subsequently, a single-factor experiment was employed to test the impact of several parameters on the efficiency of lycopene extraction using this selected ionic liquid. These parameters included extraction time, ultrasonic power, liquid-solid ratio, concentration of the ionic liquid, as well as material particle size. Moreover, models of artificial neural networks using genetic algorithms (ANN-GA) and response surface methodology (RSM) were employed to comprehensively assess the first four key parameters. The optimized conditions for ionic liquid ultrasound-assisted extraction (IL-UAE) were determined as follows: 33 min of extraction time, 225 W of ultrasonic power, 22 mL/g of liquid-solid ratio, 3.0 mol/L of IL concentration, and extraction cycles of three. Under these conditions, lycopene production reached an impressive yield of 9.35 ± 0.36 mg/g while offering advantages such as high efficiency, time savings, preservation benefits, and most importantly environmental friendliness.

2.
Wound Repair Regen ; 2024 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-38602068

RESUMO

Both cutaneous radiation injury and radiation combined injury (RCI) could have serious skin traumas, which are collectively referred to as radiation-associated skin injuries in this paper. These two types of skin injuries require special managements of wounds, and the therapeutic effects still need to be further improved. Cutaneous radiation injuries are common in both radiotherapy patients and victims of radioactive source accidents, which could lead to skin necrosis and ulcers in serious conditions. At present, there are still many challenges in management of cutaneous radiation injuries including early diagnosis, lesion assessment, and treatment prognosis. Radiation combined injuries are special and important issues in severe nuclear accidents, which often accompanied by serious skin traumas. Mass victims of RCI would be the focus of public health concern. Three-dimensional (3D) bioprinting, as a versatile and favourable technique, offers effective approaches to fabricate biomimetic architectures with bioactivity, which provides potentials for resolve the challenges in treating radiation-associated skin injuries. Combining with the cutting-edge advances in 3D skin bioprinting, the authors analyse the damage characteristics of skin wounds in both cutaneous radiation injury and RCI and look forward to the potential value of 3D skin bioprinting for the treatments of radiation-associated skin injuries.

3.
Neuroradiology ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587561

RESUMO

PURPOSE: To develop and validate a prediction model based on imaging data for the prognosis of mild chronic subdural hematoma undergoing atorvastatin treatment. METHODS: We developed the prediction model utilizing data from patients diagnosed with CSDH between February 2019 and November 2021. Demographic characteristics, medical history, and hematoma characteristics in non-contrast computed tomography (NCCT) were extracted upon admission to the hospital. To reduce data dimensionality, a backward stepwise regression model was implemented to build a prognostic prediction model. We calculated the area under the receiver operating characteristic curve (AUC) of the prognostic prediction model by a tenfold cross-validation procedure. RESULTS: Maximum thickness, volume, mean density, morphology, and kurtosis of the hematoma were identified as the most significant predictors of good hematoma dissolution in mild CSDH patients undergoing atorvastatin treatment. The prediction model exhibited good discrimination, with an area under the curve (AUC) of 0.82 (95% confidence interval [CI], 0.74-0.90) and good calibration (p = 0.613). The validation analysis showed the AUC of the final prognostic prediction model is 0.80 (95% CI 0.71-0.86) and it has good prediction performance. CONCLUSION: The imaging data-based prediction model has demonstrated great prediction accuracy for good hematoma dissolution in mild CSDH patients undergoing atorvastatin treatment. The study results emphasize the importance of imaging data evaluation in the management of CSDH patients.

4.
Sensors (Basel) ; 24(6)2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38544057

RESUMO

An accurate calculation of the indicator diagram of a pumping unit is the key factor in analyzing the performance of an oilfield production and operation and in preparing and optimizing an oilfield development plan. Aiming at the problems of the poor stability of the conventional load-displacement sensor method and the wave equation method, owing to the influence of an alternating load on the force sensor and the difficulty in measuring the crank angle using the electrical parameter method, a new soft sensing method employing the input electrical parameters of the motor and the beam inclination has been proposed to obtain the indicator diagram. At first, this method is established based on the beam angle of the pumping unit, which is easily measured using the suspension point displacement mathematics calculation model and the torque factor. Subsequently, the electric motor input parameters, the parameters of the four-bar linkage, and the relationship between the polished rod load have been established. Finally, the motor and the beam angle of the measured electrical parameters have been substituted into the calculation of the suspension point displacement and load value and pull in accordance with the guidelines to eliminate the singularity mutation values. After processing the measured data through a Butterworth filter, the indicator diagram is obtained. The results of the engineering experiment and application show that the average relative error of the method is less than 3.95%, and the maximum relative error remains within 2% for 6 months, which verifies the stability of the soft sensing method.

5.
Colloids Surf B Biointerfaces ; 236: 113796, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38368756

RESUMO

Kidney disease is currently prevalent worldwide but only shows insidious symptoms in the early stages. The second near-infrared window (NIR-II) fluorescence imaging has become a widely used preclinical technology for evaluating renal dysfunction due to its high resolution and sensitivity. However, bright renal clearable NIR-II fluorescence nanoprobes with a simple synthesis process are still lacking. Herein, we develop a lactoglobulin (LG)@dye nanoprobe for NIR-II fluorescence imaging of kidney dysfunction in vivo based on a purification-free method. The nanoprobe was synthesized by simply mixing LG and IR820 in aqueous solutions at 70 °C for 2 h based on the covalent interaction between the meso-Cl in IR820 and LG. The synthesized LG@IR820 nanoprobe has bright and stable NIR-II fluorescence, ultra-small size (<5 nm), low toxicity, and renal-clearable ability. The high reaction efficiency and pure aqueous reaction media make the synthesis method purification-free. In a unilateral ureteral obstruction mouse model, incipient renal dysfunction assessment was achieved by LG@IR820 nanoprobe, which couldn't be diagnosed with conventional kidney function indicators. This study provides a bright and purification-free NIR-II LG@IR820 nanoprobe to visualize kidney dysfunction at the early stage.


Assuntos
Nefropatias , Lactoglobulinas , Animais , Camundongos , Rim/diagnóstico por imagem , Nefropatias/diagnóstico por imagem , Água , Imagem Óptica/métodos , Corantes Fluorescentes
6.
World J Gastroenterol ; 30(2): 170-183, 2024 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-38312122

RESUMO

BACKGROUND: Deep learning provides an efficient automatic image recognition method for small bowel (SB) capsule endoscopy (CE) that can assist physicians in diagnosis. However, the existing deep learning models present some unresolved challenges. AIM: To propose a novel and effective classification and detection model to automatically identify various SB lesions and their bleeding risks, and label the lesions accurately so as to enhance the diagnostic efficiency of physicians and the ability to identify high-risk bleeding groups. METHODS: The proposed model represents a two-stage method that combined image classification with object detection. First, we utilized the improved ResNet-50 classification model to classify endoscopic images into SB lesion images, normal SB mucosa images, and invalid images. Then, the improved YOLO-V5 detection model was utilized to detect the type of lesion and its risk of bleeding, and the location of the lesion was marked. We constructed training and testing sets and compared model-assisted reading with physician reading. RESULTS: The accuracy of the model constructed in this study reached 98.96%, which was higher than the accuracy of other systems using only a single module. The sensitivity, specificity, and accuracy of the model-assisted reading detection of all images were 99.17%, 99.92%, and 99.86%, which were significantly higher than those of the endoscopists' diagnoses. The image processing time of the model was 48 ms/image, and the image processing time of the physicians was 0.40 ± 0.24 s/image (P < 0.001). CONCLUSION: The deep learning model of image classification combined with object detection exhibits a satisfactory diagnostic effect on a variety of SB lesions and their bleeding risks in CE images, which enhances the diagnostic efficiency of physicians and improves the ability of physicians to identify high-risk bleeding groups.


Assuntos
Aprendizado Profundo , Humanos , Intestino Delgado/diagnóstico por imagem , Intestino Delgado/patologia
7.
J Radiat Res ; 65(2): 194-204, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38264835

RESUMO

Enterogenic infection is a common complication for patients with radiation injury and requires efficient therapeutics in the clinic. Herein, we evaluated the promising drug candidate T7E21RHD5, which is a peptide derived from intestinal Paneth cell-secreted human defensin 5. Oral administration of this peptide alleviated the diarrhea symptoms of mice that received total abdominal irradiation (TAI, γ-ray, 12 Gy) and improved survival. Pathologic analysis revealed that T7E21RHD5 elicited an obvious mitigation of ionizing radiation (IR)-induced epithelial damage and ameliorated the reduction in the levels of claudin, zonula occluden 1 and occludin, three tight junction proteins in the ileum. Additionally, T7E21RHD5 regulated the gut microbiota in TAI mice by remodeling ß diversity, manifested as a reversal of the inverted proportion of Bacteroidota to Firmicutes caused by IR. T7E21RHD5 treatment also decreased the abundance of pathogenic Escherichia-Shigella but significantly increased the levels of Alloprevotella and Prevotellaceae_NK3B31, two short-chain fatty acid-producing bacterial genera in the gut. Accordingly, the translocation of enterobacteria and lipopolysaccharide to the blood, as well as the infectious inflammatory responses in the intestine after TAI, was all suppressed by T7E21RHD5 administration. Hence, this versatile antimicrobial peptide possesses promising application prospects in the treatment of IR-induced enterogenic infection.


Assuntos
Defensinas , Peptídeos , Humanos , Camundongos , Animais , Raios gama/efeitos adversos
8.
J Contam Hydrol ; 261: 104287, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38219283

RESUMO

Semi-arid rivers are particularly vulnerable and responsive to the impacts of industrial contamination. Prompt identification and projection of pollutant dynamics are crucial in the accidental pollution incidents, therefore required the timely informed and effective management strategies. In this study, we collected water quality monitoring data from a typical semi-arid river. By water quality inter-correlation mapping, we identified the regularity and abnormal fluctuations of pollutant discharges. Combining the association rule method (Apriori) and characterized pollutants of different industries, we tracked major industrial pollution sources in the Dahei River Basin. Meanwhile, we deployed the integrated multivariate long and short-term memory network (LSTM) to forecast principal contaminants. Our findings revealed that (1) biological oxygen demand (BOD), chemical oxygen demand (COD), total nitrogen, total phosphorus, and ammonia nitrogen exhibited high inter-correlations in water quality mapping, with lead and cadmium also demonstrating a strong association; (2) The main point sources of contaminant were coking, metal mining, and smelting industries. The government should strengthen the regulation and control of these industries and prevent further pollution of the river; (3) We confirmed 4 key pollutants: COD, ammonia nitrogen, total nitrogen, and total phosphorus. Our study accurately predicted the future changes in this water quality index. The best results were obtained when the prediction period was 1 day. The prediction accuracies reached 85.85%, 47.15%, 85.66%, and 89.07%, respectively. In essence, this research developed effective water quality traceability and predictive analysis methods in semi-arid river basins. It provided an effective tool for water quality surveillance in semi-arid river basins and imparts a scientific scaffold for the environmental stewardship endeavors of pertinent authorities.


Assuntos
Aprendizado Profundo , Poluentes Químicos da Água , Qualidade da Água , Monitoramento Ambiental/métodos , Amônia/análise , Poluentes Químicos da Água/análise , Rios/química , Nitrogênio/análise , Fósforo , China , Poluição da Água/análise
9.
J Sep Sci ; 47(1): e2300606, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38095460

RESUMO

QiXueShuFu Decoction (QXSFD) modified from the Bazhen Decoction which was originally from the classic Ming Dynasty is a traditional folk formula that boosts the body's immune system. However, its ambiguous chemical components limited its quality control evaluation. In this study, ultra-performance liquid chromatography (UPLC) fingerprint combined with multivariate analysis was used to evaluate the quality of 15 batches of QXSFD, and UPLC quadrupole-orbitrap mass spectrometry was used to further examine the chemical components in QXSFD, after which representative compounds from each disassembled prescription were selected for comparison. Fifteen batches of samples had 33 common peaks in which 11 differential components could be used as a reference for subsequent quality control. One hundred forty-three components were identified from QXSFD. Saponins were mainly derived from the monarch, terpenes from the minister, and polysaccharides and glycosides from the assistant. In addition, quantitative assay revealed that the content of ferulic acid, chlorogenic acid, 2,3,5,4'-tetrahydroxystilbene-2-O-ß-D-glucoside and 3,6'-disinapoyl sucrose in the whole prescription were higher than the contents of each disassembled prescription. This is the first comprehensive quality report on the chemical components of QXSFD, which is important for pharmacodynamic material basis and quality control.


Assuntos
Medicamentos de Ervas Chinesas , Saponinas , Medicamentos de Ervas Chinesas/análise , Cromatografia Líquida de Alta Pressão/métodos , Glicosídeos , Saponinas/análise
10.
Ann Hepatol ; 29(2): 101279, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38123132

RESUMO

INTRODUCTION AND OBJECTIVES: Cholangiocarcinoma (CCA) is characterized by early distant invasion and metastasis, whereas the underlying mechanism is still obscure. Increasing evidence shows that collagen type Ι alpha 1 (COL1A1) is a gene associated with the progression of multiple diseases. Here, we attempted to investigate the role of COL1A1 in CCA. MATERIALS AND METHODS: The expression of COL1A1 between tumor tissues and adjacent normal tissues obtained from CCA patients was detected by Western blot and immunofluorescence, followed by analysis of its clinical significance. Then, the biological effects of COL1A1 overexpression or knockdown on CCA cells were evaluated in vitro and in vivo. Finally, molecular mechanism of COL1A1 in regulating the invasion and metastasis of CCA cells was determined by a series of experiments. RESULTS: COL1A1 expression was significantly higher in CCA pathological tissues than in corresponding adjacent normal tissues. Analysis of 83 CCA patients showed that higher expression of COL1A1 was correlated with poorer patient prognosis. Notably, overexpression or knockdown experiments revealed that COL1A1 contributed to the migration and invasion, as well as epithelial-to-mesenchymal transition (EMT), in CCA cells. Further investigations demonstrated that matrix metalloproteinase-2 (MMP2) promoted COL1A1 upregulation via the integrin alpha Ⅴ pathway, therefore affecting ECM remodelling and inducing EMT in CCA cells. Moreover, COL1A1 expression was positively related to PD-1 and PD-L1 in CCA, and COL1A1 increased PD-L1 expression by activating the NF-κB pathway. CONCLUSIONS: COL1A1 plays an important role in regulating CCA progression and may act as a promising biomarker and therapeutic target for CCA.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Antígeno B7-H1/genética , Antígeno B7-H1/metabolismo , Neoplasias dos Ductos Biliares/patologia , Ductos Biliares Intra-Hepáticos/patologia , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Colangiocarcinoma/patologia , Regulação Neoplásica da Expressão Gênica , Integrina alfaV/genética , Integrina alfaV/metabolismo , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo
11.
Mil Med Res ; 10(1): 66, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38111039

RESUMO

BACKGROUND: The essential roles of platelets in thrombosis have been well recognized. Unexpectedly, thrombosis is prevalent during thrombocytopenia induced by cytotoxicity of biological, physical and chemical origins, which could be suffered by military personnel and civilians during chemical, biological, radioactive, and nuclear events. Especially, thrombosis is considered a major cause of mortality from radiation injury-induced thrombocytopenia, while the underlying pathogenic mechanism remains elusive. METHODS: A mouse model of radiation injury-induced thrombocytopenia was built by exposing mice to a sublethal dose of ionizing radiation (IR). The phenotypic and functional changes of platelets and megakaryocytes (MKs) were determined by a comprehensive set of in vitro and in vivo assays, including flow cytometry, flow chamber, histopathology, Western blotting, and chromatin immunoprecipitation, in combination with transcriptomic analysis. The molecular mechanism was investigated both in vitro and in vivo, and was consolidated using MK-specific knockout mice. The translational potential was evaluated using a human MK cell line and several pharmacological inhibitors. RESULTS: In contrast to primitive MKs, mature MKs (mMKs) are intrinsically programmed to be apoptosis-resistant through reprogramming the Bcl-xL-BAX/BAK axis. Interestingly, mMKs undergo minority mitochondrial outer membrane permeabilization (MOMP) post IR, resulting in the activation of the cyclic GMP-AMP synthase-stimulator of IFN genes (cGAS-STING) pathway via the release of mitochondrial DNA. The subsequent interferon-ß (IFN-ß) response in mMKs upregulates a GTPase guanylate-binding protein 2 (GBP2) to produce large and hyperreactive platelets that favor thrombosis. Further, we unmask that autophagy restrains minority MOMP in mMKs post IR. CONCLUSIONS: Our study identifies that megakaryocytic mitochondria-cGAS/STING-IFN-ß-GBP2 axis serves as a fundamental checkpoint that instructs the size and function of platelets upon radiation injury and can be harnessed to treat platelet pathologies.


Assuntos
Lesões por Radiação , Trombocitopenia , Trombose , Humanos , Animais , Camundongos , Megacariócitos/metabolismo , Megacariócitos/patologia , Trombocitopenia/etiologia , Apoptose , Nucleotidiltransferases/metabolismo , Trombose/metabolismo
12.
Neuroimage Clin ; 40: 103541, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37972450

RESUMO

OBJECTIVE: Investigate the brain functional networks associated with motor impairment in people with Parkinson's disease (PD). BACKGROUND: PD is primarily characterized by motor dysfunction. Resting-state functional connectivity (RsFC) offers a unique opportunity to non-invasively characterize brain function. In this study, we hypothesized that the motor dysfunction observed in people with PD involves atypical connectivity not only in motor but also in higher-level attention networks. Understanding the interaction between motor and non-motor RsFC that are related to the motor signs could provide insights into PD pathophysiology. METHODS: We used data from 88 people with PD (mean age: 68.2(SD:10), 55 M/33F) coming from 2 cohorts. Motor severity was assessed in practical OFF-medication state, using MDS-UPDRS Part-III motor scores (mean: 49 (SD:10)). RsFC was characterized using an atlas of 384 regions that were grouped into 13 functional networks. Associations between RsFC and motor severity were assessed independently for each RsFC using predictive modeling. RESULTS: The top 5 % models that predicted the MDS-UPDRS-III motor scores with effect size >0.5 were the connectivity between (1) the somatomotor and Subcortical-Basal-ganglia, (2) somatomotor and Visual and (3) CinguloOpercular (CiO) and language/Ventral attention (Lan/VeA) network pairs. DISCUSSION: Our findings suggest that, along with motor networks, visual- and attention-related cortical networks are also associated with the motor symptoms of PD. Non-motor networks may be involved indirectly in motor-coordination. When people with PD have deficits in motor networks, more attention may be needed to carry out formerly automatic motor functions, consistent with compensatory mechanisms in parkinsonian movement disorders.


Assuntos
Doença de Parkinson , Humanos , Idoso , Doença de Parkinson/complicações , Doença de Parkinson/diagnóstico por imagem , Doença de Parkinson/tratamento farmacológico , Imageamento por Ressonância Magnética , Gânglios da Base , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico
14.
Kidney Int ; 104(5): 956-974, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37673285

RESUMO

After acute kidney injury (AKI), renal tubular epithelial cells (RTECs) are pathologically characterized by intracellular lipid droplet (LD) accumulation, which are involved in RTEC injury and kidney fibrosis. However, its pathogenesis remains incompletely understood. The protein, αKlotho, primarily expressed in RTECs, is well known as an anti-aging hormone wielding versatile functions, and its membrane form predominantly acts as a co-receptor for fibroblast growth factor 23. Here, we discovered a connection between membrane αKlotho and intracellular LDs in RTECs. Fluorescent fatty acid (FA) pulse-chase assays showed that membrane αKlotho deficiency in RTECs, as seen in αKlotho homozygous mutated (kl/kl) mice or in mice with ischemia-reperfusion injury (IRI)-induced AKI, inhibited FA mobilization from LDs by impairing adipose triglyceride lipase (ATGL)-mediated lipolysis and lipophagy. This resulted in LD accumulation and FA underutilization. IRI-induced alterations were more striking in αKlotho deficiency. Mechanistically, membrane αKlotho deficiency promoted E3 ligase peroxin2 binding to ubiquitin-conjugating enzyme E2 D2, resulting in ubiquitin-mediated degradation of ATGL which is a common molecular basis for lipolysis and lipophagy. Overexpression of αKlotho rescued FA mobilization by preventing ATGL ubiquitination, thereby lessening LD accumulation and fibrosis after AKI. This suggests that membrane αKlotho is indispensable for the maintenance of lipid homeostasis in RTECs. Thus, our study identified αKlotho as a critical regulator of lipid turnover and homeostasis in AKI, providing a viable strategy for preventing tubular injury and the AKI-to-chronic kidney disease transition.

15.
Cerebrovasc Dis ; 2023 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-37722371

RESUMO

INTRODUCTION: Moyamoya disease (MMD) is a vascular disease with significant risk of mortality due to ischemia or hemorrhage in the brain. The goal of the study was to explore three-dimensional arterial spin labeling (3D-ASL) to improve evaluation of cerebral hemodynamics in patients with MMD. METHODS: Our study included 54 cases of ischemic MMD and 42 cases of hemorrhagic MMD. Dynamic susceptibility contrast-enhanced perfusion weighted imaging (DSC-PWI) and 3D-ASL were performed at 3.0 T. Based on these scans, cerebral blood flow (CBF), mean transit time (MTT) and time to peak (TTP) were calculated and compared between patients with different disease subtypes. Receiver operating characteristics (ROC) analysis was used to assess the diagnostic sensitivity and specificity of different imaging procedures and parameters. RESULTS: Our data suggested that CBF in the lesion area was more severely reduced in patients with hemorrhagic MMD than in those with ischemic MMD. The CBF parameter in 3D-ASL diagnosed hemorrhagic and ischemic MMD with a significant sensitivity and specificity of 80.59% and 57.41% respectively, with an area under the curve (AUC) of 0.75. We also found that the relative CBF (rCBF) of 3D-ASL was more pronounced decreased and the relative MTT and TTP of DSC-PWI were significantly increased in patients with hemorrhagic MMD than those with ischemic MMD. Specificity and sensitivity, and AUC of 3D-ASL were better than the comparison of absolute values from DSC-PWI scans. DISCUSSION/CONCLUSION: Our study indicated that 3D-ASL is powerful in differentiating patients with cerebral ischemic or hemorrhagic MMD, providing another diagnostic tool that could potentially improve precision medicine to monitoring MMD patients.

16.
Cell Mol Immunol ; 20(10): 1216-1231, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37644165

RESUMO

Although DNA mutation drives stem cell aging, how mutation-accumulated stem cells obtain clonal advantage during aging remains poorly understood. Here, using a mouse model of irradiation-induced premature aging and middle-aged mice, we show that DNA mutation accumulation in hematopoietic stem cells (HSCs) during aging upregulates their surface expression of major histocompatibility complex class II (MHCII). MHCII upregulation increases the chance for recognition by bone marrow (BM)-resident regulatory T cells (Tregs), resulting in their clonal expansion and accumulation in the HSC niche. On the basis of the establishment of connexin 43 (Cx43)-mediated gap junctions, BM Tregs transfer cyclic adenosine monophosphate (cAMP) to aged HSCs to diminish apoptotic priming and promote their survival via activation of protein kinase A (PKA) signaling. Importantly, targeting the HSC-Treg interaction or depleting Tregs effectively prevents the premature/physiological aging of HSCs. These findings show that aged HSCs use an active self-protective mechanism by entrapping local Tregs to construct a prosurvival niche and obtain a clonal advantage.


Assuntos
Células-Tronco Hematopoéticas , Linfócitos T Reguladores , Medula Óssea , Senescência Celular , DNA/metabolismo
17.
BMC Biol ; 21(1): 169, 2023 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-37553612

RESUMO

BACKGROUND: The nutrient-absorbing villi of small intestines are renewed and repaired by intestinal stem cells (ISCs), which reside in a well-organized crypt structure. Genetic studies have shown that Wnt molecules secreted by telocytes, Gli1+ stromal cells, and epithelial cells are required for ISC proliferation and villus homeostasis. Intestinal stromal cells are heterogeneous and single-cell profiling has divided them into telocytes/subepithelial myofibroblasts, myocytes, pericytes, trophocytes, and Pdgfralow stromal cells. Yet, the niche function of these stromal populations remains incompletely understood. RESULTS: We show here that a Twist2 stromal lineage, which constitutes the Pdgfralow stromal cell and trophocyte subpopulations, maintains the crypt structure to provide an inflammation-restricting niche for regenerating ISCs. Ablating Twist2 lineage cells or deletion of one Wntless allele in these cells disturbs the crypt structure and impairs villus homeostasis. Upon radiation, Wntless haplo-deficiency caused decreased production of anti-microbial peptides and increased inflammation, leading to defective ISC proliferation and crypt regeneration, which were partially rescued by eradication of commensal bacteria. In addition, we show that Wnts secreted by Acta2+ subpopulations also play a role in crypt regeneration but not homeostasis. CONCLUSIONS: These findings suggest that ISCs may require different niches for villus homeostasis and regeneration and that the Twist2 lineage cells may help to maintain a microbe-restricted environment to allow ISC-mediated crypt regeneration.


Assuntos
Linhagem da Célula , Homeostase , Intestinos , Nicho de Células-Tronco , Células-Tronco , Células-Tronco/citologia , Células-Tronco/metabolismo , Intestinos/citologia , Intestinos/metabolismo , Mucosa Intestinal/citologia , Mucosa Intestinal/metabolismo , Animais , Camundongos
18.
Foods ; 12(15)2023 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-37569174

RESUMO

Meat product is the main food and major source of daily protein intake. Polyphenols are always introduced into many meat products during processing. Some complex interactions may occur between polyphenol and meat protein during the processing, especially thermal processing, which may affect the digestion of protein. In this experiment, chicken protein and tea polyphenol were interacted in simulated systems to explore the effects of the interaction between meat protein and polyphenols on the digestion of meat protein. The mechanism of tea polyphenol inhibiting chicken protein digestion was studied by analyzing the changes of chicken protein in intrinsic fluorescence, surface plasmon resonance (SPR), reactive sulfhydryl group, and solubility in different solvents. The results showed that the chicken protein digestion had a negative correlation with tea polyphenol concentration and interaction temperature, and the meat protein has a higher affinity to EGCG than protease. The mechanism of tea polyphenol inhibiting chicken protein digestion was related to the changing spatial structure of chicken protein and the decreasing activity of proteases. In the simulation system, at low-concentration tea polyphenol, the inhibition of the tea polyphenol on the digestibility of chicken protein might be mainly caused by the changes in chicken protein structure, while at high concentration, the changes in protein structure and the inhibition of proteases activity played a role together. This experiment revealed the effect and the mechanism of polyphenols on the digestion performance of meat protein and provide more references for the further application of polyphenols in meat processing.

19.
Artigo em Inglês | MEDLINE | ID: mdl-37440378

RESUMO

As a recent noticeable topic, domain generalization aims to learn a generalizable model on multiple source domains, which is expected to perform well on unseen test domains. Great efforts have been made to learn domain-invariant features by aligning distributions across domains. However, existing works are often designed based on some relaxed conditions which are generally hard to satisfy and fail to realize the desired joint distribution alignment. In this article, we propose a novel domain generalization method, which originates from an intuitive idea that a domain-invariant classifier can be learned by minimizing the Kullback-Leibler (KL)-divergence between posterior distributions from different domains. To enhance the generalizability of the learned classifier, we formalize the optimization objective as an expectation computed on the ground-truth marginal distribution. Nevertheless, it also presents two obvious deficiencies, one of which is the side-effect of entropy increase in KL-divergence and the other is the unavailability of ground-truth marginal distributions. For the former, we introduce a term named maximum in-domain likelihood to maintain the discrimination of the learned domain-invariant representation space. For the latter, we approximate the ground-truth marginal distribution with source domains under a reasonable convex hull assumption. Finally, a constrained maximum cross-domain likelihood (CMCL) optimization problem is deduced, by solving which the joint distributions are naturally aligned. An alternating optimization strategy is carefully designed to approximately solve this optimization problem. Extensive experiments on four standard benchmark datasets, i.e., Digits-DG, PACS, Office-Home, and miniDomainNet, highlight the superior performance of our method.

20.
Oncogene ; 42(34): 2547-2557, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37443303

RESUMO

Rho GTPase-activating protein 4 (ARHGAP4) is an important Rho family GTPase-activating protein that is strongly associated with the onset and progression of some tumors. We found that ARHGAP4 mRNA and protein are overexpressed in human acute myeloid leukemia (AML) patients and are associated with a poor prognosis. ARHGAP4 knockdown significantly impairs viability and colony formation capacity and induces apoptosis in AML cells. Further results demonstrate that ARHGAP4 deletion impairs AML progression in vivo. Interestingly, DRAM1 signaling is significantly activated in AML cells with ARHGAP4 knockdown. Our results also indicated that ARHGAP4 might function in AML cells by binding with p53 to inhibit DRAM1. Moreover, knockdown of DRAM1 rescues the defects of ARHGAP4 in AML cells. This newly described role of the ARHGAP4/DRAM1 axis in regulating AML progression may have important therapeutic implications.


Assuntos
Leucemia Mieloide Aguda , Humanos , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Proteínas Ativadoras de GTPase/genética , Leucemia Mieloide Aguda/patologia , Proteínas de Membrana/genética , RNA Mensageiro , Transdução de Sinais
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