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1.
J Plast Surg Hand Surg ; : 1-6, 2022 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-35522455

RESUMO

Photodynamic therapy (PDT) is a new therapy for treating cancer with less toxicity, high selectivity, good cooperativity, and repetitive usability. However, keloid treatment by PDT is mainly focused on clinical appearance, and few studies have been conducted on the mechanisms of PDT. In this study, key factors of the classical mitochondrial apoptosis signaling pathway were measured to assess the effect of a new PDT photosensitizer (p1). A specific inhibitor of caspase-8 (Z-IETD-FMK) was also used to verify the possible mechanisms. Twelve samples were obtained from 12 patients (six with keloids and six without) selected randomly from the Department of Plastic Surgery at Peking Union Medical College Hospital from January to December 2020. After cell culture, fibroblasts were divided into 13 groups. The morphology of fibroblasts in each group was observed by microscopy. Cell activity was measured by cell counting kit-8, and cell apoptotic morphology was observed by TUNEL staining. The reactive oxygen species (ROS) relative value was measured by a ROS test kit. The expression levels of key mitochondrial factors (caspase-3, caspase-8, cytochrome-c, Bax, and Bcl-2) were assessed by western blot, and mRNA expression of caspase-3 and caspase-8 was measured by RT-qPCR. We showed that p1 had a satisfactory proapoptotic effect on keloid fibroblasts by increasing the expression of ROS, caspase-3, caspase-8, and cytochrome-c, and decreasing the Bcl-2/Bax ratio; however, this effect was partially inhibited by Z-IETD-FMK, indicating that caspase-8 may be one of the p1's targets to achieve the proapoptotic effect.

2.
Food Chem ; 390: 133094, 2022 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-35545003

RESUMO

Current regulatory limit values for paralytic shellfish toxins (PSTs) in shellfish products are not considering the bioaccessibility of PSTs in seafood matrix during the gastrointestinal digestion for human beings. In this study, the bioaccessibility of PSTs in the shellfish cooked by different ways was assessed using a static in vitro human digestion model. Results showed that the dissolution of PSTs from shellfish tissues was not significantly affected by digestion time, ratios of solid weight to liquid volume (S/L) and cooking methods, but obviously facilitated by digestive enzymes. Different cooking ways reduced the contents of PSTs in shellfish by 45% to 88%, but did not significantly change the high bioaccessibility of PSTs that ranged from 80% to 95% in four different shellfish matrices. Transformation or degradation of PSTs occurred during the simulated digestion process. This work will help us to objectively assess the potential risks of PSTs to human health.

3.
Front Neurosci ; 16: 808824, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35546893

RESUMO

Understanding the structure-function relationship in a neuronal network is one of the major challenges in neuroscience research. Despite increasing researches at circuit connectivity and neural network structure, their structure-based biological interpretability remains unclear. Based on the attractor theory, here we develop an analytical framework that links neural circuit structures and their functions together through fixed point attractor in Caenorhabditis elegans. In this framework, we successfully established the structural condition for the emergence of multiple fixed points in C. elegans connectome. Then we construct a finite state machine to explain how functions related to bistable phenomena at the neural activity and behavioral levels are encoded. By applying the proposed framework to the command circuit in C. elegans, we provide a circuit level interpretation for the forward-reverse switching behaviors. Interestingly, network properties of the command circuit and first layer amphid interneuron circuit can also be inferred from their functions in this framework. Our research indicates the reliability of the fixed point attractor bridging circuit structure and functions, suggesting its potential applicability to more complex neuronal circuits in other species.

4.
Front Microbiol ; 13: 829027, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35547119

RESUMO

Environmental microorganisms (EMs) are ubiquitous around us and have an important impact on the survival and development of human society. However, the high standards and strict requirements for the preparation of environmental microorganism (EM) data have led to the insufficient of existing related datasets, not to mention the datasets with ground truth (GT) images. This problem seriously affects the progress of related experiments. Therefore, This study develops the Environmental Microorganism Dataset Sixth Version (EMDS-6), which contains 21 types of EMs. Each type of EM contains 40 original and 40 GT images, in total 1680 EM images. In this study, in order to test the effectiveness of EMDS-6. We choose the classic algorithms of image processing methods such as image denoising, image segmentation and object detection. The experimental result shows that EMDS-6 can be used to evaluate the performance of image denoising, image segmentation, image feature extraction, image classification, and object detection methods. EMDS-6 is available at the https://figshare.com/articles/dataset/EMDS6/17125025/1.

5.
Front Plant Sci ; 13: 873071, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35548281

RESUMO

Allopolyploids exist widely in nature and have strong environmental adaptability. The typical allopolyploid Brassica napus L. is a widely cultivated crop, but whether it is superior to its diploid progenitors in abiotic stress resistance and the key genes that may be involved are not fully understood. Cystein-rich polycomb-like protein (CPP) genes encode critical transcription factors involved in the response of abiotic stress, including salt stress. To explore the potential molecular basis of allopolyploid adaptation to salt stress, we comprehensively analyzed the characteristics and salt stress response of the CPP genes in B. napus and its two diploid progenitors in this study. We found some molecular basis that might be associated with the adaptability of B. napus, including the expansion of the CPP gene family, the acquisition of introns by some BnCPPs, and abundant cis-acting elements upstream of BnCPPs. We found two duplication modes (whole genome duplication and transposed duplication) might be the main reasons for the expansion of CPP gene family in B. napus during allopolyploidization. CPP gene expression levels and several physiological indexes were changed in B. napus and its diploid progenitors after salt stress, suggesting that CPP genes might play important roles in the response of salt stress. We found that some BnCPPs might undergo new functionalization or subfunctionalization, and some BnCPPs also show biased expression, which might contribute to the adaptation of B. napus under saline environment. Compared with diploid progenitors, B. napus showed stronger physiological responses, and BnCPP gene expression also showed higher changes after salt stress, indicating that the allopolyploid B. napus had an adaptive advantage under salt stress. This study could provide evidence for the adaptability of polyploid and provide important clues for the study of the molecular mechanism of salt stress resistance in B. napus.

6.
Mitochondrial DNA B Resour ; 7(5): 744-746, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35558183

RESUMO

Paphiopedilum 'GZSLKY Youyou'. is a new cultivar of Paphiopedilum with highly ornamental and horticultural value developed by crossing female parent Paphiopedilum dianthum T. Tang & F. T. Wang 1940 and male parent Paphiopedilum barbigerum T. Tang & F. T. Wang 1940. In this study, the complete chloroplast genome of the cultivar has been reconstructed from the Illumina sequencing data. The circular genome was 160,503 bp in size, containing a large single-copy region (91,582 bp), a small single-copy region (3,215 bp) and a pair of IR regions (each one 32,853 bp). The overall GC contents of the chloroplast genome was 36.20%. The chloroplast genome contained 122 genes, including 76 protein coding genes, 38 tRNA genes and 8 rRNA genes. A maximum likelihood (ML) phylogenetic tree showed that the cultivar 'GZSLKY Youyou' was clustered into the same clade with its parents and was closest related to P. dianthum, reflecting a maternal inheritance of chloroplasts. This complete chloroplast genome resource could be further used for genomic studies, phylogenetic analyses, and genetic engineering and breeding of the genus Paphiopedilum.

7.
Fitoterapia ; : 105216, 2022 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-35569638

RESUMO

Seven lignans (1a/1b-2a/2b and 3-5), including six new compounds (1b, 2a/2b, 3-5), were isolated from the fruits of Crataegus pinnatifida. Their structures were elucidated by comprehensive spectroscopic analyses. Compounds 1b/1b-2a/2b were two pairs of enantiomers and the absolute configurations were determined by comparison of their experimental and calculated ECD spectra. Moreover, bioinformatics analysis suggested that more than a third of diseases were related to the nervous system. Therefore, all compounds were evaluated for neuroprotective effects toward human neuroblastoma SH-SY5Y cells injury induced by H2O2. Among them, compound 1a exhibited moderate protective effect.

8.
Artigo em Inglês | MEDLINE | ID: mdl-35503932

RESUMO

How to achieve high sensing of Cr2O3-based sensors for harmful inorganic gases is still a challenge. To this end, Cr2O3 nanomaterials assembled from different building blocks were simply prepared by chromium salt immersion and air calcination with waste scallion roots as the biomass template. The hierarchical architecture calcined at 600 °C is constructed from nanocylinders and nanoellipsoids (named as Cr2O3-600), and also possesses multistage pore distribution for target gas accessibility. Interestingly, the synergism of two shapes of nanocrystals enables the Cr2O3-based sensor to realize highly sensitive detection of trace H2S gas. At 170 °C, Cr2O3-600 exhibits a high response of 42.8 to 100 ppm H2S gas, which is 3.45 times larger than that of Cr2O3-500 assembled from nanocylinders. Meanwhile, this sensor has a low detection limit of 1.0 ppb (S = 1.4), good selectivity, stability, and moisture resistance. These results show that the combination of nanosized cylinders/ellipsoids together with exposed (104) facet can effectively improve the sensing performance of the p-type Cr2O3 material. In addition, the Cr2O3-600 sensor shows satisfactory results for actual monitoring of the corruption process of fresh chicken.

9.
Ann Vasc Surg ; 2022 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-35568328

RESUMO

BACKGROUND: Endovascular repair of the thoracic aorta (TEVAR) outcomes have been studied with interest in complications related to left subclavian artery (LSA) coverage in patients with atherosclerotic pathologies; however, specific data on the management of the LSA in a trauma population is lacking. The objective of this study is to evaluate outcomes following TEVAR for traumatic aortic injury based on LSA coverage. METHODS: The Vascular Quality Initiative thoracic endovascular aortic repair module (2010-2017) was analyzed. Patients were included if they had a traumatic aortic injury requiring TEVAR. Patients were placed in two groups based on coverage of the left subclavian artery. Patients were propensity score matched and the primary outcomes were cerebrovascular symptoms and spinal cord ischemia. Additional clinical and resource utilization outcomes were analyzed. RESULTS: 451 patients were included in the analysis. There were 268 patients in the LSA not covered group and 183 patients in the LSA covered group. The mean aortic injury grade was 2.88±0.056 vs 2.88±0.049 in the covered versus not-covered group (p=0.957). Glasgow coma scale and injury severity score were not different between the groups. There was no difference between groups for cerebrovascular symptoms or spinal cord ischemia, 1.4% vs 2.8% p=0.684 and 0% vs 2.1% p=0.247, after propensity score matching. Significant differences in access site complications and resource utilization were identified between groups. CONCLUSION: This is the largest series to evaluate complications based on LSA coverage following TEVAR in trauma patients. Our data demonstrate that coverage of the LSA during TEVAR following blunt trauma is associated with no difference in CNS outcomes. As such, LSA revascularization strategies, while possible, are not directly supported by these data, and should be individualized based on each patient's specific clinical scenario.

10.
Cell Death Dis ; 13(5): 434, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35508480

RESUMO

As a critical member of the ubiquitin-specific proteolytic enzyme family, ubiquitin-specific peptidase 20 (USP20) regulates the stability of proteins via multiple signaling pathways. In addition, USP20 upregulation is associated with various cellular biological processes, such as cell cycle progression, proliferation, migration, and invasion. Emerging studies have revealed the pivotal role of USP20 in the tumorigenesis of various cancer types, such as breast cancer, colon cancer, lung cancer, gastric cancer and adult T cell leukemia. In our review, we highlight the different mechanisms of USP20 in various tumor types and demonstrate that USP20 regulates the stability of multiple proteins. Therefore, regulating the activity of USP20 is a novel tumor treatment. However, the clinical significance of USP20 in cancer treatment merits more evidence. Finally, different prospects exist for the continued research focus of USP20.


Assuntos
Neoplasias da Mama , Ubiquitina Tiolesterase , Transformação Celular Neoplásica , Feminino , Humanos , Ubiquitina Tiolesterase/genética , Ubiquitina Tiolesterase/metabolismo , Proteases Específicas de Ubiquitina/genética , Proteases Específicas de Ubiquitina/metabolismo , Ubiquitinação
11.
Sci Rep ; 12(1): 7231, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35508571

RESUMO

The potential for preventive and therapeutic applications of H2 have now been confirmed in various disease. However, the effects of H2 on health status have not been fully elucidated. Our previous study reported changes in the body weight and 13 serum biochemical parameters during the six-month hydrogen intervention. To obtain a more comprehensive understanding of the effects of long-term hydrogen consumption, the plasma metabolome and gut microbiota were investigated in this study. Compared with the control group, 14 and 10 differential metabolites (DMs) were identified in hydrogen-rich water (HRW) and hydrogen inhalation (HI) group, respectively. Pathway enrichment analysis showed that HRW intake mainly affected starch and sucrose metabolism, and DMs in HI group were mainly enriched in arginine biosynthesis. 16S rRNA gene sequencing showed that HRW intake induced significant changes in the structure of gut microbiota, while no marked bacterial community differences was observed in HI group. HRW intake mainly induced significant increase in the abundance of Lactobacillus, Ruminococcus, Clostridium XI, and decrease in Bacteroides. HI mainly induced decreased abundances of Blautia and Paraprevotella. The metabolic function was determined by metabolic cage analysis and showed that HI decreased the voluntary intake and excretions of rats, while HRW intake did not. The results of this study provide basic data for further research on hydrogen medicine. Determination of the effects of hydrogen intervention on microbiota profiles could also shed light on identification of mechanism underlying the biological effects of molecular hydrogen.


Assuntos
Microbioma Gastrointestinal , Animais , Ingestão de Líquidos , Nível de Saúde , Hidrogênio/metabolismo , RNA Ribossômico 16S/genética , Ratos
12.
Hypertension ; 79(6): 1247-1256, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35360932

RESUMO

BACKGROUND: Recent evidence indicates that long-term visit-to-visit blood pressure variability (BPV) may be associated with risk of cardiovascular disease. We, therefore, aimed to determine the potential associations of long-term BPV from childhood to middle age with subclinical kidney damage (SKD) and albuminuria in adulthood. METHODS: Using data from the ongoing cohort of Hanzhong Adolescent Hypertension study, which recruited children and adolescents aged 6 to 18 years at baseline, we assessed BPV by SD and average real variability (ARV) for 30 years (6 visits). Presence of SKD was defined as estimated glomerular filtration rate between 30 and 60 mL/min per 1.73 m2 or elevated urinary albumin-to creatinine ratio at least 30 mg/g. Albuminuria was defined as urinary albumin-to creatinine ratio ≥30 mg/g. RESULTS: During 30 years of follow-up, of the 1771 participants, 204 SKD events occurred. After adjustment for demographic, clinical characteristics, and mean BP during 30 years, higher SDSBP , ARVSBP , SDDBP , ARVDBP , SDMAP , ARVMAP , and ARVPP were significantly associated with higher risk of SKD. When we used cumulative exposure to BP from childhood to adulthood instead of mean BP as adjustment factors, results were similar. In addition, greater long-term BPV was also associated with the risk of albuminuria. Long-term BPV from childhood to middle age was associated with higher risk of SKD and albuminuria in adulthood, independent of mean BP or cumulative exposure to BP during follow-up. CONCLUSIONS: Identifying long-term BPV from early age may assist in predicting kidney disease and cardiovascular disease in later life.

14.
Front Neurol ; 13: 847418, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35481274

RESUMO

Object: Although revision surgery for recurrent craniopharyngiomas is more challenging than primary surgery and often accompanies a higher risk of death and complications, endoscopic endonasal transsphenoidal surgery (EETS) is sometimes still an effective and reliable treatment option. In this study, we introduced the surgical outcomes of EETS for recurrent craniopharyngiomas and summarized the surgical experiences. Methods: Between 2014 and 2018, 28 patients with recurrent craniopharyngiomas underwent 29 EETS in our department. We regarded the patient undergoing two EETS as two independent patients in statistical analysis. Of the 29 patients, 16 had undergone 1 previous surgery, 10 had undergone 2 previous surgeries, and the remaining 3 patients had undergone 3 surgeries. The extent of resection, visual and endocrine outcomes, and complications of all the patients were collected and analyzed. Results: Gross total resection was accomplished in 16 patients (55.17%), subtotal resection in 11 patients (37.93%), and partial resection in 2 patients (6.9%). Among the 22 patients with preoperative visual acuity and visual field impairment, some degree of vision improvement was observed in 18 patients, 3 patients were without visual change, and perpetual deterioration of vision occurred in one patient. The remaining six patients had normal vision before and after surgery. Postoperative endocrine tests showed that, among five patients with normal preoperative pituitary hormone function, only one patient still had normal pituitary hormone function and the other four patients had one or more hypothalamic-pituitary axes involved. None of the patients with preoperative endocrine dysfunction had endocrine function improved. Diabetes insipidus was observed in six new cases postoperatively. Cerebrospinal fluid (CSF) leakage occurred in 1 patient. One patient had bacterial meningitis, which was cured with antibiotics and a lumbar drain. No serious morbidity and mortality occurred in all patients. Conclusions: For recurrent craniopharyngiomas, a personalized treatment plan should be developed according to the tumor characteristics and the patient's situation. There is no omnipotent method to be used for all patients. The EETS still is a safe and effective way to treat recurrent craniopharyngiomas in appropriate patients.

15.
Front Endocrinol (Lausanne) ; 13: 812802, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35464049

RESUMO

STATs (Signal Transducers and Activators of Transcription) 5A and 5B are induced during adipocyte differentiation and are primarily activated by growth hormone (GH) and prolactin in fat cells. Previous studies in mice lacking adipocyte GH receptor or STAT5 support their roles in lipolysis-mediated reduction of adipose tissue mass. Male and female mice harboring adipocyte-specific deletion of both STAT5 genes (STAT5AKO) exhibit increased subcutaneous or inguinal adipose tissue mass, but no changes in visceral or gonadal fat mass. Both depots display substantial increases in adipocyte size with no changes in lipolysis in adipose tissue explants. RNA sequencing analysis of subcutaneous adipose tissue and indirect calorimetry experiments reveal sex-dependent differences in adipose gene expression and whole-body energy expenditure, respectively, resulting from the loss of adipocyte STAT5.


Assuntos
Adiposidade , Lipólise , Adipócitos/metabolismo , Tecido Adiposo/metabolismo , Adiposidade/genética , Animais , Feminino , Lipólise/genética , Masculino , Camundongos , Obesidade/genética , Obesidade/metabolismo , Fator de Transcrição STAT5/genética
16.
Int J Biol Sci ; 18(6): 2497-2514, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35414791

RESUMO

Protein homeostasis is well accepted as the prerequisite for proper operation of various life activities. As the main apparatus of protein translation, ribosomes play an indispensable role in the maintenance of protein homeostasis. Nevertheless, upon stimulation of various internal and external factors, malfunction of ribosomes may be evident with the excessive production of aberrant proteins, accumulation of which can result in deleterious effects on cellular fate and even cell death. Ribosomopathies are characterized as a series of diseases caused by abnormalities of ribosomal compositions and functions. Correspondingly, cell evolves several ribosome quality control mechanisms in maintaining the quantity and quality of intracellular ribosomes, namely ribosome quality control system (RQCS). Of note, RQCS can tightly monitor the entire process from ribosome biogenesis to its degradation, with the capacity of coping with ribosomal dysfunction, including misassembled ribosomes and incorrectly synthesized ribosomal proteins. In the current literature review, we mainly introduce the RQCS and elaborate on the underlying pathogenesis of several ribosomopathies. With the in-depth understanding of ribosomal dysfunction and molecular basis of RQCS, therapeutic strategy by specifically targeting RQCS remains a promising option in treating patients with ribosomopathies and other ribosome-associated human diseases.


Assuntos
Eucariotos , Proteínas Ribossômicas , Eucariotos/metabolismo , Humanos , Biossíntese de Proteínas , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo , Ribossomos/genética , Ribossomos/metabolismo
17.
Int J Mol Sci ; 23(7)2022 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-35409258

RESUMO

Single cell RNA sequencing (scRNA-seq) allows researchers to explore tissue heterogeneity, distinguish unusual cell identities, and find novel cellular subtypes by providing transcriptome profiling for individual cells. Clustering analysis is usually used to predict cell class assignments and infer cell identities. However, the performance of existing single-cell clustering methods is extremely sensitive to the presence of noise data and outliers. Existing clustering algorithms can easily fall into local optimal solutions. There is still no consensus on the best performing method. To address this issue, we introduce a single cell self-paced clustering (scSPaC) method with F-norm based nonnegative matrix factorization (NMF) for scRNA-seq data and a sparse single cell self-paced clustering (sscSPaC) method with l21-norm based nonnegative matrix factorization for scRNA-seq data. We gradually add single cells from simple to complex to our model until all cells are selected. In this way, the influences of noisy data and outliers can be significantly reduced. The proposed method achieved the best performance on both simulation data and real scRNA-seq data. A case study about human clara cells and ependymal cells scRNA-seq data clustering shows that scSPaC is more advantageous near the clustering dividing line.


Assuntos
Análise de Célula Única , Transcriptoma , Algoritmos , Análise por Conglomerados , Perfilação da Expressão Gênica/métodos , Humanos , Análise de Sequência de RNA/métodos , Análise de Célula Única/métodos
18.
Materials (Basel) ; 15(7)2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35407842

RESUMO

Understanding the essence of the flow oscillations within a submerged-entry nozzle (SEN) is essential to control flow patterns in the continuous casting mold and consequently increase the superficial quality of steel products. A numerical study of the mesoscopic fluid-particle flow in a bifurcated pool-type SEN under steady operating conditions is conducted using the lattice Boltzmann method (LBM) coupled with the large eddy simulation (LES) model. The accuracy of the model has been verified by comparing vortex structures and simulated velocities with published experimental values. The LBM modeling is also verified by comparing the "stair-step" jet patterns observed in the experiment. The geometrical parameters and operational conditions of physical experiments are reproduced in the simulations. By comparing the time-averaged velocities of Reynolds-averaged Navier-Stokes equations (RANS) with LBM models, transient mesoscopic fluid-particles and related vortex structures can be better reproduced within the SEN. The visualization of internal flow within the SEN is illustrated through the mass-less Discrete Phase Model (DPM) model. The trajectories show that the LBM-LES-DPM coupled model is good at predicting the transient vortical flow within the SEN. A large vortex is found inside the exit port and continuously changes in shape and size therein. The monitoring points and lines within the SEN are selected to illustrate the velocity variations and effective viscosity, which can reflect the oscillating characteristics even under stable operating conditions without changes at the exit from the SEN. Furthermore, the formation, development, diffusion, and dissipation of the vortex structures from the exit port of the SEN are also investigated using the Q criteria. The comparison of the power spectrum with high-frequency components along the exit port indicates that the flow oscillations must originate from within the SEN and are intensified in the exit port. The mesoscopic LBM model can replicate the fluid-particle flow and vortex structure transmission as well as their turbulence effects inside the SEN in detail.

19.
PLoS One ; 17(4): e0265049, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35404961

RESUMO

Human dermal fibroblasts (HDFs) play important roles in all stages of wound healing. However, in nonhealing wounds, fibroblasts are prone to aging, resulting in insufficient migration, proliferation and secretion functions. Recent studies have suggested that mesenchymal stromal cells (MSCs) are conducive to wound healing and cell growth through paracrine cytokine signaling. In our studies, we found that conditioned medium of MSCs pretreated with IFN-γ and TNF-α (IT MSC-CM) has abundant growth factors associated with wound repair. Our in vitro results showed that the effects of IT MSC-CM on promoting cell migration, proliferation and activation in HDFs were better than those of conditioned medium from mesenchymal stromal cells (MSC-CM). Moreover, we embedded a scaffold material containing IT MSC-CM and reconfirmed that cell migration and activation were superior to that in the presence of MSC-CM in vivo. Generally, PDGF-BB is perceived as a promoter of the migration and proliferation of HDFs. Moreover, a high level of PDGF-BB in IT MSC-CM was detected, according to which we guess that the effect on HDFs may be mediated by the upregulation of PDGF-BB. These studies all showed the potential of IT MSC-CM to promote rapid and effective wound healing.


Assuntos
Citocinas , Células-Tronco Mesenquimais , Becaplermina/metabolismo , Movimento Celular , Proliferação de Células , Meios de Cultivo Condicionados/metabolismo , Meios de Cultivo Condicionados/farmacologia , Citocinas/metabolismo , Fibroblastos/metabolismo , Humanos
20.
ACS Appl Mater Interfaces ; 14(17): 20073-20082, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35439417

RESUMO

It is challenging to design complex synthetic life-like systems that can show both autoevolution and fuel-driven transient behaviors. Here, we report a new class of chemical reaction networks (CRNs) to construct life-like polymer hydrogels. The CRNs are constituted of autocatalytic cascade reactions and fuel-driven reaction networks. The reactions start with only two compounds, that is, thiol of 4-arm-PEG-SH and thiuram disulfides, and undergo thiol oxidation (k1), disulfide metathesis (k2), and thionate hydrolysis-coupling reactions (k3) subsequently, leading to a four-state autonomous transition of sol(I) → soft gel → sol(II) → stiff gel. Moreover, thiuram disulfides can be applied as a fuel to drive the repeated occurrence of metathesis and hydrolysis-coupling reactions, generating dissipative stiff gel → sol(II) → stiff gel cycles. Systematic kinetics studies reveal that the event and lifetime of every transient state could be delicately tailored-up by varying the thiuram disulfide concentration, pH of the system, and thiuram structures. Since the consecutive transient behaviors are precisely predictable, we envision the strategy's potential in guiding the molecular designs of autonomous and adaptive materials for many fields.

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