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1.
Front Oncol ; 13: 1136729, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37213285

RESUMO

Background: The heterogeneous crosstalk between tumor cells and other cells in their microenvironment means a notable difference in clinical outcomes of head and neck squamous cell carcinoma (HNSCC). CD8+ T cells and macrophages are effector factors of the immune system, which have direct killing and phagocytosis effects on tumor cells. How the evolution of their role in the tumor microenvironment influences patients clinically remains a mystery. This study aims to investigate the complex communication networks in the HNSCC tumor immune microenvironment, elucidate the interactions between immune cells and tumors, and establish prognostic risk model. Methods: 20 HNSCC samples single-cell rna sequencing (scRNA-seq) data and bulk rna-seq data were derived from public databases. The "cellchat" R package was used to identify cell-to-cell communication networks and prognostic related genes, and then cell-cell communication (ccc) molecular subtypes were constructed by unsupervised clustering. Kaplan-Meier(K-M) survival analysis, clinical characteristics analysis, immune microenvironment analysis, immune cell infiltration analysis and CD8+T cell differentiation correlation analysis were performed. Finally, the ccc gene signature including APP, ALCAM, IL6, IL10 and CD6 was constructed based on univariate Cox analysis and multivariate Cox regression. Kaplan-Meier analysis and time-dependent receiver operating characteristic (ROC) analysis were used to evaluate the model in the train group and the validation group, respectively. Results: With CD8+T cells from naive to exhaustion state, significantly decreased expression of protective factor (CD6 gene) is associated with poorer prognosis in patients with HNSCC. The role of macrophages in the tumor microenvironment has been identified as tumor-associated macrophage (TAM), which can promote tumor proliferation and help tumor cells provide more nutrients and channels to facilitate tumor cell invasion and metastasis. In addition, based on the strength of all ccc in the tumor microenvironment, we identified five prognostic ccc gene signatures (cccgs), which were identified as independent prognostic factors by univariate and multivariate analysis. The predictive power of cccgs was well demonstrated in different clinical groups in train and test cohorts. Conclusion: Our study highlights the propensity for crosstalk between tumors and other cells and developed a novel signature on the basis of a strong association gene for cell communication that has a powerful ability to predict prognosis and immunotherapy response in patients with HNSCC. This may provide some guidance for developing diagnostic biomarkers for risk stratification and therapeutic targets for new therapeutic strategies.

2.
Bioact Mater ; 20: 194-207, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35702607

RESUMO

Meniscus is a wedge-shaped fibrocartilaginous tissue, playing important roles in maintaining joint stability and function. Meniscus injuries are difficult to heal and frequently progress into structural breakdown, which then leads to osteoarthritis. Regeneration of heterogeneous tissue engineering meniscus (TEM) continues to be a scientific and translational challenge. The morphology, tissue architecture, mechanical strength, and functional applications of the cultivated TEMs have not been able to meet clinical needs, which may due to the negligent attention on the importance of microenvironment in vitro and in vivo. Herein, we combined the 3D (three-dimensional)-printed gradient porous scaffolds, spatiotemporal partition release of growth factors, and anti-inflammatory and anti-oxidant microenvironment regulation of Ac2-26 peptide to prepare a versatile meniscus composite scaffold with heterogeneous bionic structures, excellent biomechanical properties and anti-inflammatory and anti-oxidant effects. By observing the results of cell activity and differentiation, and biomechanics under anti-inflammatory and anti-oxidant microenvironments in vitro, we explored the effects of anti-inflammatory and anti-oxidant microenvironments on construction of regional and functional heterogeneous TEM via the growth process regulation, with a view to cultivating a high-quality of TEM from bench to bedside.

3.
Ann Transl Med ; 9(18): 1421, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34733973

RESUMO

BACKGROUND: Conventional surgical treatment for metacarpal giant cell tumours (GCTs) includes lesion scraping followed by bone grafting or bone cement filling and en bloc resection followed by repair and reconstruction using a vascularised bone flap. However, these methods have inherent shortcomings, including a high postoperative recurrence rate and poor mechanical stability. 3D-printing techniques are increasingly being applied in medicine, and 3D-printed personalised prostheses have achieved good clinical effects in orthopaedic repair and reconstruction. We aimed to investigate the clinical effects of 3D-printed personalised prostheses for bone defect repair and reconstruction following resection of metacarpal GCTs. METHODS: Three patients with metacarpal GCTs were examined in a retrospective cohort study. Through preoperative planning, a 3D-printed personalised prosthesis was designed and created for bone defect repair and reconstruction after tumour resection. Prosthesis fit, limb function, pain on the affected side, and the occurrence of complications were evaluated postoperatively. RESULTS: Postoperative X-ray examination revealed a satisfactory fit of the 3D-printed prosthesis in terms of bone defect size and overall metacarpal shape, as well as good transverse and longitudinal metacarpal arches. The patients also exhibited good function in the affected limb, with good flexion and extension functions in the carpal, metacarpophalangeal, and interphalangeal joints, plus the absence of obvious pain, tumour recurrence, and complications such as pathologic fractures and prosthetic loosening. CONCLUSIONS: When using a 3D-printed personalised prosthesis for bone defect repair and reconstruction following resection of metacarpal GCTs, a good fit with the bone defect can be achieved during prosthetic installation when preoperative planning and design have been adequately performed. Therefore, three-dimensionally printed personalised prostheses can serve as an effective method for the treatment of metacarpal GCTs.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32676499

RESUMO

Human endometrial stem cells (hEnSCs), dental pulp stem cells (hDPSCs) and adipose tissue-derived stem cells (hADSCs) are considered to be the promising candidates for the treatment of pancreas diseases. The prognosis is better with in situ injection of mesenchymal stem cells (MSCs) to the damaged pancreas compared with intravenous injection. However, the clinical application of these cells are limited, due to poor engraftment of transplanted cells after delivery. On the other hand, understanding the role of the biomaterials in cell therapy is essential to promote the therapeutic effects of MSCs. Matrigel, a basement membrane matrix biomaterial, is rich in laminin and collagen IV. The aim of this study is to investigate the difference of biological characteristics of hEnSCs, hDPSCs and hADSCs in vitro and their survival situation with Matrigel post intrapancreatic transplantation in vivo. Our findings showed, firstly, there was no significant difference in morphology and immunophenotype of these MSCs. Secondly, the biological properties, including cell proliferation, the ability of adipogenic and osteogenic differentiation and the mRNA expression levels of pancreas development-related genes, have been showed distinct difference among these MSCs. Thirdly, Matrigel can improve the survival of MSCs in vivo, especially for Matrigel-based hDPSCs and Matrigel-based hEnSCs in pancreas parenchyma of SD rats. These results suggest that hDPSCs and hEnSCs are with the greater inherent therapeutic potential for pancreas diseases compared with hADSCs.

5.
Front Pharmacol ; 11: 471, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32431606

RESUMO

Poly(ε-caprolactone) (PCL) derived scaffolds have been extensively explored in the field of tissue-engineered meniscus (TEM) originating from their good biosafety and biomechanical properties. However, the poor intrinsic hydrophobicity severely hindered their wide applications for the scaffold-assisted tissue regeneration. Herein, we developed a simple strategy on surface modification of three-dimensional (3D) PCL scaffolds via a simply soaking treatment of sodium hydroxide (NaOH) solutions to increase the hydrophilicity and roughness of scaffolds' surfaces. We investigated the effect of hydrolysis degree mediated by NaOH solutions on mechanical properties of 3D scaffolds, considering the importance of scaffolds' resistance to internal force. We also investigated and analyzed the biological performances of mesenchymal stromal cells (MSCs) and meniscal fibrocartilage cells (MFCs) onto the scaffolds treated or untreated by NaOH solutions. The results indicated that hydrophilic modification could improve the proliferation and attachment of cells on the scaffolds. After careful screening process condition, structural fabrication, and performance optimization, these modified PCL scaffolds possessed roughened surfaces with inherent hierarchical pores, enhanced hydrophilicity and preferable biological performances, thus exhibiting the favorable advantages on the proliferation and adhesion of seeded cells for TEM. Therefore, this feasible hydrophilic modification method is not only beneficial to promote smarter biomedical scaffold materials but also show great application prospect in tissue engineering meniscus with tunable architectures and desired functionalities.

6.
Artigo em Inglês | MEDLINE | ID: mdl-32296692

RESUMO

Osteochondral damage from trauma or osteoarthritis is a general joint disease that can lead to an increased social and economic burden in the modern society. The inefficiency of osteochondral defects is mainly due to the absence of suitable tissue-engineered substrates promoting tissue regeneration and replacing damaged areas. The hydrogels are becoming a promising kind of biomaterials for tissue regeneration. The biomimetic hydrogel microenvironment can be tightly controlled by modulating a number of biophysical and biochemical properties, including matrix mechanics, degradation, microstructure, cell adhesion, and intercellular interactions. In particular, advances in stem cell-laden hydrogels have offered new ideas for the cell therapy and osteochondral repair. Herein, the aim of this review is to underpin the importance of stem cell-laden hydrogels on promoting the development of osteochondral regeneration, especially in the field of manipulation of biomimetic microenvironment and utilization growth factors with various delivery methods.

7.
Med Sci Monit ; 24: 2946-2969, 2018 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-29735972

RESUMO

BACKGROUND The aim of this study was to assess the efficacy and safety of acupuncture therapy for patients with hypertension. MATERIAL AND METHODS We searched PubMed, Embase, the Cochrane Library, the Chinese Biomedical Literature Database, the Chinese National Knowledge Infrastructure, and the Wan-fang Data Database from inception through 29 April 2017. Randomized controlled trials investigating acupuncture therapy for hypertension were included. Review Manager 5.3 software was used for the data analysis. RESULTS A total of 30 RCTs involving 2107 patients were included. The overall methodological quality of the included studies was low. Pooled results demonstrate that acupuncture plus anti-hypertensive drugs is better than anti-hypertensive drugs alone at reducing systolic and diastolic blood pressure (SBP and DBP). The same result was observed for pooled data from experiments that compared acupuncture plus medication to sham acupuncture plus medication at reducing SBP and DBP. However, studies reveal that using acupuncture alone or anti-hypertensive drugs alone do not differ in the effect on lowering blood pressure. Similarly, acupuncture alone also did not differ from sham acupuncture alone, and electroacupuncture versus anti-hypertensive drugs was not significantly different at reducing SBP and DBP. CONCLUSIONS Our systematic review indicates there is inadequate high quality evidence that acupuncture therapy is useful in treating hypertension, as the exact effect and safety of acupuncture therapy for hypertension is still unclear. Therefore, research with larger sample sizes and higher-quality RCTs is still needed.


Assuntos
Terapia por Acupuntura/efeitos adversos , Hipertensão Essencial/terapia , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea , Diástole , Eletroacupuntura , Hipertensão Essencial/tratamento farmacológico , Hipertensão Essencial/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Viés de Publicação , Ensaios Clínicos Controlados Aleatórios como Assunto , Relatório de Pesquisa , Sístole , Resultado do Tratamento
8.
Toxicol In Vitro ; 47: 156-164, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29155130

RESUMO

Dibromoacetic acid (DBA), a haloacetic acid by-product of disinfection of drinking water, can cause many adverse effects in test animals, including immunotoxicity. However, the underlying molecular mechanism for the immunomodulatory effects remains unclear. The present study was undertaken to help in defining some potential mechanisms for this type of toxicity. Here, Cl.Ly1+2/-9 T-cells were exposed to varying levels of DBA and then several parameters, including cell survival, apoptosis, changes in mitochondrial potentials, and effects on select kinases (i.e., p38, ERK1/2, JNK1/2) were examined. The data showed that DBA significantly decreased Cl.Ly1+2/-9 cell viability in a dose-related manner. DBA also induced apoptosis, a decrease in mitochondrial trans-membrane potential, and up-regulated the protein expression of cleaved caspase-3. Moreover, DBA increased the phosphorylation of all three mitogen-activated protein kinases (MAPKs) evaluated. Pre-treatment with specific p38, ERK1/2, and JNK1/2 inhibitors (SB203580, U0126, SP600125, respectively) attenuated the inducible phosphorylation events. DBA also induced up-regulation of mRNA levels of the MAPKs downstream transcription factors ATF-2 and Elk-1. When taken together, the results suggest that DBA could induce murine Cl.Ly1+2/-9 T-cells apoptosis through mitochondria-dependent way, and activate the MAPKs pathways and downstream transcription factors ATF-2 and Elk-1.


Assuntos
Acetatos/toxicidade , Alquilantes/toxicidade , Apoptose/efeitos dos fármacos , Fatores Imunológicos/toxicidade , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Fator 2 Ativador da Transcrição/agonistas , Fator 2 Ativador da Transcrição/genética , Fator 2 Ativador da Transcrição/metabolismo , Animais , Caspase 3/química , Caspase 3/genética , Caspase 3/metabolismo , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Regulação da Expressão Gênica/efeitos dos fármacos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Concentração Osmolar , Fosforilação/efeitos dos fármacos , Proteólise/efeitos dos fármacos , Linfócitos T/imunologia , Linfócitos T/metabolismo , Proteínas Elk-1 do Domínio ets/agonistas , Proteínas Elk-1 do Domínio ets/genética , Proteínas Elk-1 do Domínio ets/metabolismo
10.
Am J Sports Med ; 45(7): 1497-1511, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28278383

RESUMO

BACKGROUND: Total meniscectomy leads to knee osteoarthritis in the long term. The poly(ε-caprolactone) (PCL) scaffold is a promising material for meniscal tissue regeneration, but cell-free scaffolds result in relatively poor tissue regeneration and lead to joint degeneration. HYPOTHESIS: A novel, 3-dimensional (3D)-printed PCL scaffold augmented with mesenchymal stem cells (MSCs) would offer benefits in meniscal regeneration and cartilage protection. STUDY DESIGN: Controlled laboratory study. METHODS: PCL meniscal scaffolds were 3D printed and seeded with bone marrow-derived MSCs. Seventy-two New Zealand White rabbits were included and were divided into 4 groups: cell-seeded scaffold, cell-free scaffold, sham operation, and total meniscectomy alone. The regeneration of the implanted tissue and the degeneration of articular cartilage were assessed by gross and microscopic (histological and scanning electron microscope) analysis at 12 and 24 weeks postoperatively. The mechanical properties of implants were also evaluated (tensile and compressive testing). RESULTS: Compared with the cell-free group, the cell-seeded scaffold showed notably better gross appearance, with a shiny white color and a smooth surface. Fibrochondrocytes with extracellular collagen type I, II, and III and proteoglycans were found in both seeded and cell-free scaffold implants at 12 and 24 weeks, while the results were significantly better for the cell-seeded group at week 24. Furthermore, the cell-seeded group presented notably lower cartilage degeneration in both femur and tibia compared with the cell-free or meniscectomy group. Both the tensile and compressive properties of the implants in the cell-seeded group were significantly increased compared with those of the cell-free group. CONCLUSION: Seeding MSCs in the PCL scaffold increased its fibrocartilaginous tissue regeneration and mechanical strength, providing a functional replacement to protect articular cartilage from damage after total meniscectomy. CLINICAL RELEVANCE: The study suggests the potential of the novel 3D PCL scaffold augmented with MSCs as an alternative meniscal substitution, although this approach requires further improvement before being used in clinical practice.


Assuntos
Cartilagem Articular/cirurgia , Meniscos Tibiais/cirurgia , Transplante de Células-Tronco Mesenquimais/instrumentação , Poliésteres/farmacologia , Impressão Tridimensional , Engenharia Tecidual/instrumentação , Alicerces Teciduais , Animais , Cartilagem Articular/fisiologia , Masculino , Meniscos Tibiais/fisiologia , Impressão Tridimensional/instrumentação , Coelhos , Engenharia Tecidual/métodos
11.
Am J Transl Res ; 7(10): 1724-35, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26692920

RESUMO

Oxidative stress plays an important role in doxorubicin (DOX)-induced cardiotoxicity. Nuclear factor E2-related factor-2 (Nrf2) is a transcription factor that orchestrates the antioxidant and cytoprotective responses to oxidative stress. In the present study, we tested whether tert-butylhydroquinone (tBHQ) could protect against DOX-induced cardiotoxicity in vivo and, if so, whether the protection was associated with the up-regulation of the Nrf2 pathway. The results showed that treatment with tBHQ significantly decreased the DOX-induced cardiac injury in wild-type mice. Moreover, tBHQ ameliorated the DOX-induced oxidative stress and apoptosis. Further studies suggested that tBHQ increased the nuclear accumulation of Nrf2 and the Nrf2-regulated gene expression, including heme oxygenase-1 (HO-1) and NAD(P)H: quinone oxido-reductase-1 (NQO-1) expression. Knocking out Nrf2 in mice abolished the protective effect of tBHQ on the DOX-induced cardiotoxicity. These results indicate that tBHQ has a beneficial effect on DOX-induced cardiotoxicity, and this effect was associated with the enhanced expression of Nrf2 and its downstream antioxidant genes, HO-1 and NQO-1.

12.
Plant Signal Behav ; 8(10)2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24270689

RESUMO

Seed development of flowering plant is a complicated process controlled by a signal network. Double fertilization generates 2 zygotic products (embryo and endosperm). Embryo gives rise to a daughter plant while endosperm provides nutrients for embryo during embryogenesis and germination. Seed coat differentiates from maternally derived integument and encloses embryo and endosperm. Seed size/mass and number comprise final seed yield, and seed shape also contributes to seed development and weight. Seed size is coordinated by communication among endosperm, embryo, and integument. Seed number determination is more complex to investigate and shows differences between monocot and eudicot. Total seed number depends on sillique number and seed number per sillique in Arabidopsis. Seed comes from fertilized ovule, hence the ovule number per flower determines the maximal seed number per sillique. Early studies reported that engineering BR levels increased the yield of ovule and seed; however the molecular mechanism of BR regulation in seed development still remained unclear. Our recent studies demonstrated that BR regulated seed size, shape, and number by transcriptionally modulating specific seed developmental pathways. This review summarizes roles of BR in Arabidopsis seed development and gives clues for future application of BR in agricultural production.


Assuntos
Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Brassinosteroides/metabolismo , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Regulação da Expressão Gênica de Plantas
13.
Plant Physiol ; 162(4): 1965-77, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23771896

RESUMO

Seed development is important for agriculture productivity. We demonstrate that brassinosteroid (BR) plays crucial roles in determining the size, mass, and shape of Arabidopsis (Arabidopsis thaliana) seeds. The seeds of the BR-deficient mutant de-etiolated2 (det2) are smaller and less elongated than those of wild-type plants due to a decreased seed cavity, reduced endosperm volume, and integument cell length. The det2 mutant also showed delay in embryo development, with reduction in both the size and number of embryo cells. Pollination of det2 flowers with wild-type pollen yielded seeds of normal size but still shortened shape, indicating that the BR produced by the zygotic embryo and endosperm is sufficient for increasing seed volume but not for seed elongation, which apparently requires BR produced from maternal tissues. BR activates expression of SHORT HYPOCOTYL UNDER BLUE1, MINISEED3, and HAIKU2, which are known positive regulators of seed size, but represses APETALA2 and AUXIN RESPONSE FACTOR2, which are negative regulators of seed size. These genes are bound in vivo by the BR-activated transcription factor BRASSINAZOLE-RESISTANT1 (BZR1), and they are known to influence specific processes of integument, endosperm, and embryo development. Our results demonstrate that BR regulates seed size and seed shape by transcriptionally modulating specific seed developmental pathways.


Assuntos
Arabidopsis/fisiologia , Brassinosteroides/metabolismo , Sementes/fisiologia , Proteínas de Arabidopsis/efeitos dos fármacos , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Brassinosteroides/farmacologia , Sistema Enzimático do Citocromo P-450/genética , Proteínas de Ligação a DNA , Regulação da Expressão Gênica de Plantas , Proteínas de Homeodomínio/genética , Mutação , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Plantas Geneticamente Modificadas , Proteínas Quinases/genética , Proteínas Repressoras/genética , Sementes/anatomia & histologia , Sementes/efeitos dos fármacos , Fatores de Transcrição/genética
14.
Mol Plant ; 6(2): 456-69, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22914576

RESUMO

Ovule and seed developments are crucial processes during plant growth, which are affected by different signaling pathways. In this paper, we demonstrate that the brassinosteroid (BR) signal is involved in ovule initiation and development. Ovule and seed numbers are significantly different when comparing BR-related mutants to wild-type controls. Detailed observation indicates that BR regulates the expression level of genes related to ovule development, including HLL, ANT, and AP2, either directly by targeting the promoter sequences or indirectly via regulation by BR-induced transcription factor BZR1. Also, Western blot demonstrates that the dephosphorylation level of BZR1 is consistent with ovule and seed number. The intragenic bzr1-1D suppressors bzs247 and bzs248 have much fewer ovules and seeds than bzr1-1D, which are similar to wild-type, suggesting that the phenotype can be rescued. The molecular and genetic experiments confirm that BZR1 and AP2 probably affect Arabidopsis ovule number determination antagonistically.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/genética , Brassinosteroides/metabolismo , Regulação da Expressão Gênica de Plantas , Proteínas Nucleares/metabolismo , Óvulo Vegetal/crescimento & desenvolvimento , Sementes/crescimento & desenvolvimento , Transdução de Sinais , Arabidopsis/citologia , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Mutação , Proteínas Nucleares/genética , Fenótipo , Fosforilação
15.
Wei Sheng Wu Xue Bao ; 44(6): 733-6, 2004 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-16110949

RESUMO

Soil samples were collected from six kinds of soil in Haibei alpine meadow ecosystem during 2001 - 2002. More than 300 strains of actinomycete were isolated by five agar media. On the basis of morphological characteristics and some chemotaxonomic properties, the isolated strains were classified into different genera, such as Micromonospora, Nocardia, Saccharopolyspora, Promicromonospora, Streptomyces, and the Streptomyces strains were classified into seven groups. The result indicated that the biodiversity of actinomycetes in different soils and the actinomycetes abundance of different kinds showed significant differences. The activities of some enzymes produced by mesophilic and psychrophilic actinomycetes also discussed in this paper. It is found that many strains of streptomyces not only have some enzyme activities such as starch decomposition, nitrate deoxidization, gelatin utilization etc., but also have some inhibiting activities for fungi and bacteria offered to test, whereas the rare actinomyces showed low positive rate of enzyme activities and inhibiting activities for fungi and bacteria.


Assuntos
Actinobacteria/isolamento & purificação , Microbiologia do Solo , Actinobacteria/enzimologia
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