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1.
Org Biomol Chem ; 22(18): 3611-3614, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38630011

RESUMO

Herein, we report that prism[6]arenes (PrS[6]R) can form charge-transfer (CT) inclusion complexes with tropylium tetrakis[3,5-bis(trifluoromethyl)-phenyl]borate (G) in chloroform solution with an obvious CT band at 560 nm. Moreover, the CT complex PrS[6]Et⊃G showed Cl-/Ag+ responsiveness which can be easily monitored by the naked eye.

3.
Biomed Pharmacother ; 168: 115632, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37806094

RESUMO

Spinal Cord Injury (SCI) is a devastating neurological disorder comprising primary mechanical injury and secondary inflammatory response-mediated injury for which an effective treatment is still unavailable. It is well known that secondary inflammatory responses are a significant cause of difficulties in neurological recovery. An immune imbalance between M1/M2 macrophages at the sites of injury is involved in developing and progressing the secondary inflammatory response. Recently, Mesenchymal Stem Cells (MSCs) have shown significant therapeutic potential in tissue engineering and regenerative medicine due to their potential multidirectional differentiation and immunomodulatory properties. Accumulating evidence shows that MSCs can regulate the balance of M1/M2 macrophage polarization, suppress downstream inflammatory responses, facilitate tissue repair and regeneration, and improve the prognosis of SCI. This article briefly overviews the impact of macrophages and MSCs on SCI and repair. It discusses the mechanisms by which MSCs regulate macrophage plasticity, including paracrine action, release of exosomes and apoptotic bodies, and metabolic reprogramming. Additionally, the article summarizes the relevant signaling pathways of MSCs that regulate macrophage polarization.


Assuntos
Exossomos , Células-Tronco Mesenquimais , Traumatismos da Medula Espinal , Humanos , Macrófagos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Traumatismos da Medula Espinal/tratamento farmacológico , Diferenciação Celular , Exossomos/metabolismo , Medula Espinal/metabolismo
4.
J Inflamm Res ; 16: 4763-4776, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37881652

RESUMO

Spinal Cord Injury (SCI), with its morbidity characteristics of high disability rate and high mortality rate, is a disease that is highly destructive to both the physiology and psychology of the patient, and for which there is still a lack of effective treatment. Following spinal cord injury, a cascade of secondary injury reactions known as ischemia, peripheral inflammatory cell infiltration, oxidative stress, etc. create a microenvironment that is unfavorable to neural recovery and ultimately results in apoptosis and necrosis of neurons and glial cells. Mesenchymal stem cell (MSC) transplantation has emerged as a more promising therapeutic options in recent years. MSC can promote spinal cord injury repair through a variety of mechanisms, including immunomodulation, neuroprotection, and nerve regeneration, giving patients with spinal cord injury hope. In this paper, it is discussed the neuroprotection and nerve regeneration components of MSCs' therapeutic method for treating spinal cord injuries.

5.
Front Cell Dev Biol ; 11: 1151838, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37123401

RESUMO

Bone adapts to changes in the physical environment by modulating remodeling through bone resorption and formation to maintain optimal bone mass. As the most abundant connexin subtype in bone tissue, connexin 43 (Cx43)-forming hemichannels are highly responsive to mechanical stimulation by permitting the exchange of small molecules (<1.2 kDa) between bone cells and the extracellular environment. Upon mechanical stimulation, Cx43 hemichannels facilitate the release of prostaglandins E2 (PGE2), a vital bone anabolic factor from osteocytes. Although most bone cells are involved in mechanosensing, osteocytes are the principal mechanosensitive cells, and PGE2 biosynthesis is greatly enhanced by mechanical stimulation. Mechanical stimulation-induced PGE2 released from osteocytic Cx43 hemichannels acts as autocrine effects that promote ß-catenin nuclear accumulation, Cx43 expression, gap junction function, and protects osteocytes against glucocorticoid-induced osteoporosis in cultured osteocytes. In vivo, Cx43 hemichannels with PGE2 release promote bone formation and anabolism in response to mechanical loading. This review summarizes current in vitro and in vivo understanding of Cx43 hemichannels and extracellular PGE2 release, and their roles in bone function and mechanical responses. Cx43 hemichannels could be a significant potential new therapeutic target for treating bone loss and osteoporosis.

6.
Front Cell Dev Biol ; 11: 1293101, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38178870

RESUMO

Vitiligo is a skin pigmentation disorder caused by melanocyte damage or abnormal function. Reac-tive oxygen species Reactive oxygen species can cause oxidative stress damage to melanocytes, which in turn induces vitiligo. Traditional treatments such as phototherapy, drugs, and other methods of treatment are long and result in frequent recurrences. Currently, mesenchymal stem cells (MSCs) are widely used in the research of various disease treatments due to their excellent paracrine effects, making them a promising immunoregulatory and tissue repair strategy. Furthermore, an increasing body of evi-dence suggests that utilizing the paracrine functions of MSCs can downregulate oxidative stress in the testes, liver, kidneys, and other affected organs in animal models of certain diseases. Addition-ally, MSCs can help create a microenvironment that promotes tissue repair and regeneration in are-as with oxidative stress damage, improving the disordered state of the injured site. In this article, we review the pathogenesis of oxidative stress in vitiligo and promising strategies for its treatment.

7.
Bone Res ; 10(1): 49, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35851577

RESUMO

Physical mechanical stimulation can maintain and even increase bone mass. Here, we report an important role of osteocytic integrin α5 in regulating the anabolic response of bone to mechanical loading using an Itga5 conditional gene knockout (cKO) mouse model. Integrin α5 gene deletion increased apoptotic osteocytes and reduced cortical anabolic responses to tibial compression including decreased endosteal osteoblasts and bone formation, and increased endosteal osteoclasts and bone resorption, contributing to the decreased bone area fraction and biomechanical properties, leading to an enlarged bone marrow area in cKO mice. Similar disruption of anabolic responses to mechanical loading was also detected in cKO trabecular bone. Moreover, integrin α5 deficiency impeded load-induced Cx43 hemichannel opening, and production and release of PGE2, an anabolic factor, resulting in attenuated effects of the loading on catabolic sclerostin (SOST) reduction and anabolic ß-catenin increase. Together, this study shows an indispensable role of integrin α5 in osteocytes in the anabolic action of mechanical loading on skeletal tissue through activation of hemichannels and PGE2-evoked gene expression. Integrin α5 could act as a potential new therapeutic target for bone loss, especially in the elderly population with impeded mechanical sensitivity.

8.
Elife ; 112022 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-35132953

RESUMO

Mechanical stimulation, such as physical exercise, is essential for bone formation and health. Here, we demonstrate the critical role of osteocytic Cx43 hemichannels in anabolic function of bone in response to mechanical loading. Two transgenic mouse models, R76W and Δ130-136, expressing dominant-negative Cx43 mutants in osteocytes were adopted. Mechanical loading of tibial bone increased cortical bone mass and mechanical properties in wild-type and gap junction-impaired R76W mice through increased PGE2, endosteal osteoblast activity, and decreased sclerostin. These anabolic responses were impeded in gap junction/hemichannel-impaired Δ130-136 mice and accompanied by increased endosteal osteoclast activity. Specific inhibition of Cx43 hemichannels by Cx43(M1) antibody suppressed PGE2 secretion and impeded loading-induced endosteal osteoblast activity, bone formation and anabolic gene expression. PGE2 administration rescued the osteogenic response to mechanical loading impeded by impaired hemichannels. Together, osteocytic Cx43 hemichannels could be a potential new therapeutic target for treating bone loss and osteoporosis.


Assuntos
Remodelação Óssea , Osso e Ossos/fisiologia , Conexina 43/metabolismo , Prostaglandinas/metabolismo , Animais , Fenômenos Biomecânicos , Conexina 43/genética , Dinoprostona/metabolismo , Junções Comunicantes/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mutação , Osteócitos/metabolismo , Estresse Mecânico , Suporte de Carga
10.
Cancers (Basel) ; 13(17)2021 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-34503103

RESUMO

ATP released by bone osteocytes is shown to activate purinergic signaling and inhibit the metastasis of breast cancer cells into the bone. However, the underlying molecular mechanism is not well understood. Here, we demonstrate the important roles of the CXCR4 and P2Y11 purinergic receptors in mediating the inhibitory effect of ATP on breast cancer cell migration and bone metastasis. Wound-healing and transwell migration assays showed that non-hydrolysable ATP analogue, ATPγS, inhibited migration of bone-tropic human breast cancer cells in a dose-dependent manner. BzATP, an agonist for P2X7 and an inducer for P2Y11 internalization, had a similar dose-dependent inhibition on cell migration. Both ATPγS and BzATP suppressed the expression of CXCR4, a chemokine receptor known to promote breast cancer bone metastasis, and knocking down CXCR4 expression by siRNA attenuated the inhibitory effect of ATPγS on cancer cell migration. While a P2X7 antagonist A804598 had no effect on the impact of ATPγS on cell migration, antagonizing P2Y11 by NF157 ablated the effect of ATPγS. Moreover, the reduction in P2Y11 expression by siRNA decreased cancer cell migration and abolished the impact of ATPγS on cell migration and CXCR4 expression. Similar to the effect of ATPγS on cell migration, antagonizing P2Y11 inhibited bone-tropic breast cancer cell migration in a dose-dependent manner. An in vivo study using an intratibial bone metastatic model showed that ATPγS inhibited breast cancer growth in the bone. Taken together, these results suggest that ATP inhibits bone-tropic breast cancer cells by down-regulating the P2Y11 purinergic receptor and the down-regulation of CXCR4 expression.

11.
NPJ Breast Cancer ; 7(1): 106, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34400642

RESUMO

Mammography is used to detect breast cancer (BC), but its sensitivity is limited, especially for dense breasts. Circulating cell-free DNA (cfDNA) methylation tests is expected to compensate for the deficiency of mammography. We derived a specific panel of markers based on computational analysis of the DNA methylation profiles from The Cancer Genome Atlas (TCGA). Through training (n = 160) and validation set (n = 69), we developed a diagnostic prediction model with 26 markers, which yielded a sensitivity of 89.37% and a specificity of 100% for differentiating malignant disease from normal lesions [AUROC = 0.9816 (95% CI: 96.09-100%), and AUPRC = 0.9704 (95% CI: 94.54-99.46%)]. A simplified 4-marker model including cg23035715, cg16304215, cg20072171, and cg21501525 had a similar diagnostic power [AUROC = 0.9796 (95% CI: 95.56-100%), and AUPRC = 0.9220 (95% CI: 91.02-94.37%)]. We found that a single cfDNA methylation marker, cg23035715, has a high diagnostic power [AUROC = 0.9395 (95% CI: 89.72-99.27%), and AUPRC = 0.9111 (95% CI: 88.45-93.76%)], with a sensitivity of 84.90% and a specificity of 93.88%. In an independent testing dataset (n = 104), the obtained diagnostic prediction model discriminated BC patients from normal controls with high accuracy [AUROC = 0.9449 (95% CI: 90.07-98.91%), and AUPRC = 0.8640 (95% CI: 82.82-89.98%)]. We compared the diagnostic power of cfDNA methylation and mammography. Our model yielded a sensitivity of 94.79% (95% CI: 78.72-97.87%) and a specificity of 98.70% (95% CI: 86.36-100%) for differentiating malignant disease from normal lesions [AUROC = 0.9815 (95% CI: 96.75-99.55%), and AUPRC = 0.9800 (95% CI: 96.6-99.4%)], with better diagnostic power and had better diagnostic power than that of using mammography [AUROC = 0.9315 (95% CI: 89.95-96.34%), and AUPRC = 0.9490 (95% CI: 91.7-98.1%)]. In addition, hypermethylation profiling provided insights into lymph node metastasis stratifications (p < 0.05). In conclusion, we developed and tested a cfDNA methylation model for BC diagnosis with better performance than mammography.

12.
J Clin Invest ; 131(10)2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33793424

RESUMO

BACKGROUNDCurrent clinical management of patients with pulmonary nodules involves either repeated low-dose CT (LDCT)/CT scans or invasive procedures, yet causes significant patient misclassification. An accurate noninvasive test is needed to identify malignant nodules and reduce unnecessary invasive tests.METHODWe developed a diagnostic model based on targeted DNA methylation sequencing of 389 pulmonary nodule patients' plasma samples and then validation in 140 plasma samples independently. We tested the model in different stages and subtypes of pulmonary nodules.RESULTSA 100-feature model was developed and validated for pulmonary nodule diagnosis; the model achieved a receiver operating characteristic curve-AUC (ROC-AUC) of 0.843 on 140 independent validation samples, with an accuracy of 0.800. The performance was well maintained in (a) a 6 to 20 mm size subgroup (n = 100), with a sensitivity of 1.000 and adjusted negative predictive value (NPV) of 1.000 at 10% prevalence; (b) stage I malignancy (n = 90), with a sensitivity of 0.971; (c) different nodule types: solid nodules (n = 78) with a sensitivity of 1.000 and adjusted NPV of 1.000, part-solid nodules (n = 75) with a sensitivity of 0.947 and adjusted NPV of 0.983, and ground-glass nodules (n = 67) with a sensitivity of 0.964 and adjusted NPV of 0.989 at 10% prevalence. This methylation test, called PulmoSeek, outperformed PET-CT and 2 clinical prediction models (Mayo Clinic and Veterans Affairs) in discriminating malignant pulmonary nodules from benign ones.CONCLUSIONThis study suggests that the blood-based DNA methylation model may provide a better test for classifying pulmonary nodules, which could help facilitate the accurate diagnosis of early stage lung cancer from pulmonary nodule patients and guide clinical decisions.FUNDINGThe National Key Research and Development Program of China; Science and Technology Planning Project of Guangdong Province; The National Natural Science Foundation of China National.


Assuntos
Metilação de DNA , DNA de Neoplasias/metabolismo , Neoplasias Pulmonares , Nódulos Pulmonares Múltiplos , Tomografia Computadorizada por Raios X , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Neoplasias Pulmonares/diagnóstico , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Nódulos Pulmonares Múltiplos/diagnóstico , Nódulos Pulmonares Múltiplos/diagnóstico por imagem , Nódulos Pulmonares Múltiplos/metabolismo , Estudos Retrospectivos
13.
Mol Oncol ; 15(10): 2702-2714, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-33694305

RESUMO

Screening for early-stage disease is vital for reducing colorectal cancer (CRC)-related mortality. Methylation of circulating tumor DNA has been previously used for various types of cancer screening. A novel cell-free DNA (cfDNA) methylation-based model which can improve the early detection of CRC is warranted. For our study, we collected 313 tissue and 577 plasma samples from patients with CRC, advanced adenoma (AA), non-AA and healthy controls. After quality control, 187 tissue DNA samples (91 non-malignant tissue from CRC patients, 26 AA and 70 CRC) and 489 plasma cfDNA samples were selected for targeted DNA methylation sequencing. We further developed a cfDNA methylation model based on 11 methylation biomarkers for CRC detection in the training cohort (area under curve [AUC] = 0.90 (0.85-0.94]) and verified the model in the validation cohort (AUC = 0.92 [0.88-0.96]). The cfDNA methylation model robustly detected patients pre-diagnosed with early-stage CRC (AUC = 0.90 [0.86-0.95]) or AA (AUC = 0.85 [0.78-0.91]). Here we established and validated a non-invasive cfDNA methylation model based on 11 DNA methylation biomarkers for the detection of early-stage CRC and AA. The utilization of the model in clinical practice may contribute to the early diagnosis of CRC.


Assuntos
Ácidos Nucleicos Livres , Neoplasias Colorretais , Biomarcadores Tumorais/genética , Ácidos Nucleicos Livres/genética , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Metilação de DNA/genética , Detecção Precoce de Câncer , Humanos
14.
Sci Rep ; 10(1): 21363, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33262417

RESUMO

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

15.
Chem Asian J ; 15(17): 2642-2645, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32662186

RESUMO

It is demonstrated that three kinds of neutral pentaerythritol derivatives possess promising host-guest complexations with pillar[6]arenes both in solution and in the solid state. The inclusion structures were characterized by NMR spectroscopy and X-ray crystallography. The complexation properties in different solvents were also investigated.

16.
Front Physiol ; 11: 299, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32296345

RESUMO

Connexin (Cx) 43 forms gap junctions and hemichannels that mediate communication between osteocytes and adjacent cells or the extracellular environment in bone, respectively. To investigate the role of each channel type in response to mechanical unloading, two transgenic mouse models overexpressing dominant-negative Cx43 predominantly in osteocytes driven by a 10 kb dentin matrix protein 1 (Dmp1) promoter were generated. The R76W mutation resulted in gap junction inhibition and enhancement of hemichannels, whereas the Δ130-136 mutation inhibited both gap junctions and hemichannels. Both mutations led to cortical bone loss with increased endocortical osteoclast activity during unloading. Increased periosteal osteoclasts with decreased apoptotic osteocytes were observed only in R76W mice. These findings indicated that inhibiting osteocytic Cx43 channels promotes bone loss induced by unloading, mainly in the cortical area; moreover, hemichannels protect osteocytes against apoptosis and promote periosteal bone remodeling, whereas gap junctions modulate endocortical osteoclast activity in response to unloading.

18.
Ultrason Sonochem ; 50: 354-362, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30293739

RESUMO

The influence of ultrasonic irradiation on the tar-sand bitumen in the process of thermal cracking with an inert atmosphere was investigated thoroughly. The product distribution and coke characteristic produced by the conventional thermal cracking (CTC) and ultrasound thermal cracking (UTC) were invested at the following condition: ultrasound frequency 20 kHz, ultrasonic power 2000 W, reaction time 2 h, reaction temperature from 400 to 440 °C. The result of the liquid products distribution indicated that UTC can significantly increase gasoline yield and diesel yield, and dramatically reduce VGO (Vacuum Gas Oil) yield and residuum (greater than 500 °C) yield. The analysis of gas products showed that there were no significant differences for the gas distribution between the two reactions (methods), indicating that reaction of UTC still conformed to a radical chain mechanism, but the ratio of olefin/paraffin was greatly reduced in the process of UTC, which was attributed to the hydrogen transfer reaction promoted by ultrasound. The result of the analysis by SEM, FT-IR, Raman, XRD and Zeta potential demonstrated that there was a significant difference for the morphology of cokes produced by the two methods. Mesocarbon microbeads (MCMB) was discovered in the process of UTC, which should be due to that the polymerization of the free macro-radicals produced from PAHs (Polycyclic Aromatic Hydrocarbons) promoted by ultrasonic cavitation. In addition, it can be inferred that the viscosity of the second liquid phase was reduced by ultrasonic mechanical function through the breakage of the stack of asphaltene molecules cross-linked by van der Waals force. According to the mesophase theory, the ultrasound irradiation promoted the formation of the second liquid phase, extended its existence time and reduced its viscosity, resulting in the formation of MCMB controlled by the surface tension during the process of UTC.

19.
Chem Commun (Camb) ; 54(93): 13099-13102, 2018 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-30397694

RESUMO

Herein we demonstrate that three dimensional supramolecular polymerization networks were constructed both in solution and in the solid state by the combination of pillar[5,6]arene-based host-guest complexes and 1,4-diiodotetrafluorobenzene involving halogen bonding systems.

20.
Ultrason Sonochem ; 48: 103-109, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30080531

RESUMO

In this work, a novel ultrasonic-assisted thermal cracking method for improving the yield of light oil from the thermal cracking of Huizhou atmospheric residue (HAR) is proposed and demonstrated. To achieve this, a self-developed autoclave ultrasonic reactor (20 kHz; 200 W) was designed. Gas chromatography (GC), and elemental analyser (EA) were employed to analyse the composition of gaseous and liquid products after the cracking of residual oil. Compared to the traditional thermal cracking process under similar conditions (430 °C; 8 MPa; 2 h), the ultrasonic-based process produced lower gas products (ca. 0.6%), higher gasoline and diesel fractions (ca. 10%), vacuum residue, and lower yield of coke yield (ca. 4%). In addition, coke produced by the ultrasonic-assisted thermal cracking method exhibited spherical morphology with narrow size distribution and smooth surface with small amounts of adsorbents attached to it. The derivative characteristic peak (101 crystal face) at 2θ of 43.56° belonged to α-graphite. The abnormal high local temperature and pressure conditions produced by ultrasonication were the key factors for the thermal cracking of residual oil. The experimental results indicated that the ultrasonic-assisted thermal cracking can dramatically lead to higher yield of light oil, higher degree of cleavage, and more favourable reactions under the same conditions (as those of traditional thermal cracking). Therefore, compared to the traditional delayed coking process, the proposed ultrasonic-assisted technology can significantly decrease the power consumption. This study has vital significance in predicting and enhancing the performance of thermal cracking on a large scale.

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