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1.
Nat Commun ; 15(1): 1663, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38396109

RESUMO

Targeted degradation of proteins has emerged as a powerful method for modulating protein homeostasis. Identification of suitable degraders is essential for achieving effective protein degradation. Here, we present a non-covalent degrader construction strategy, based on a modular supramolecular co-assembly system consisting of two self-assembling peptide ligands that bind cell membrane receptors and the protein of interest simultaneously, resulting in targeted protein degradation. The developed lysosome-targeting co-assemblies (LYTACAs) can induce lysosomal degradation of extracellular protein IL-17A and membrane protein PD-L1 in several scavenger receptor A-expressing cell lines. The IL-17A-degrading co-assembly has been applied in an imiquimod-induced psoriasis mouse model, where it decreases IL-17A levels in the skin lesion and alleviates psoriasis-like inflammation. Extending to asialoglycoprotein receptor-related protein degradation, LYTACAs have demonstrated the versatility and potential in streamlining degraders for extracellular and membrane proteins.


Assuntos
Psoríase , Pele , Animais , Camundongos , Pele/patologia , Interleucina-17/metabolismo , Proteólise , Psoríase/metabolismo , Receptores Depuradores/metabolismo , Proteínas de Membrana/metabolismo , Lisossomos/metabolismo , Modelos Animais de Doenças
2.
Front Med (Lausanne) ; 10: 1186143, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37265491

RESUMO

Non-infectious chronic diseases, especially inflammatory bowel diseases (IBDs), hypertension, and diabetes mellitus, are characterized by a prolonged and multisystemic course, and their incidence increases annually, usually causing serious economic burden and psychological stress for patients. Therefore, these diseases deserve scientific and consistent disease management. In addition, the lack of a comprehensive "early disease clues tracking-personalized treatment system-follow-up" model in hospitals also exacerbates this dilemma. Based on these facts, we propose an individualized prediction management system for IBDs based on chronic diseases, focusing on the established IBDs-related prediction models and summarizing their advantages and disadvantages. We call on researchers to pay attention to the integration of models with clinical practice and the continuous correction of models to achieve truly individualized medical treatment for chronic diseases, thus providing substantial value for the rapid diagnosis and adequate treatment of chronic diseases such as IBDs, which follow the "relapse-remission" disease model, and realizing long-term drug use and precise disease management for patients. The goal is to achieve a new level of chronic disease management by scientifically improving long-term medication, precise disease management, and individualized medical treatment, effectively prolonging the remission period and reducing morbidity and disability rates.

3.
Theranostics ; 12(15): 6723-6739, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36185614

RESUMO

Rationale: Cyclic dinucleotides (cDNs) are a promising class of immunotherapeutic agent targeting stimulator of interferon genes (STING). However, enzymatic instability and transmembrane barriers limit the extensive clinical application of cDNs. Thus, a novel delivery system, composed of a neutral cytidinyl lipid DNCA and a cationic lipid CLD (Mix) that interacts with cDNs via H-bonding, pi-stacking and electrostatic interaction, is developed and optimized to overcome the above issues. Methods: The optimal composition of Mix for cDNs encapsulation was explored with RAW-Lucia ISG cells. The physicochemical properties of resulted nanoparticles were characterized. To validate the anti-tumor immunity of cDNs/Mix both in vitro and in vivo, immunogenic cell death (ICD) related markers and tumor inhibition efficacy were evaluated in cancer cells and tumor models, respectively. The mechanism by which cdG/Mix exerted the antitumor effects was explored by flow cytometric analysis and in vivo depletion. Results: Based on our developed and optimized delivery system, neutral cytidinyl lipid DNCA/cationic lipid CLD (Mix), cdG (500 nM in vitro, 1-10 µg in vivo)/Mix not only more potently stimulated production of IFNß and related cytokines including CXCL9 and CXCL10, promoted ICD, led to NK and CD8+ T cell activation, inhibited tumor growth in both EO771 and B16F10 models and increased their survival rate (~43%), but also obviously reversed the T cell exhaustion (Tex) in tumor, meanwhile down regulated the mRNA expression of Tox and Nr4a, which are key regulators of Tex. Conclusion: cdG/Mix triggered ICD in various cancer cells and reversed the Tex systemically in tumor-burden mice, which would be a promising alternative strategy for cancer immunotherapy.


Assuntos
Proteínas de Membrana , Neoplasias , Animais , Linfócitos T CD8-Positivos/metabolismo , GMP Cíclico/análogos & derivados , Citocinas , Imunoterapia/métodos , Interferon beta , Lipídeos , Proteínas de Membrana/metabolismo , Camundongos , Neoplasias/patologia , RNA Mensageiro
4.
Vaccines (Basel) ; 10(6)2022 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-35746486

RESUMO

Currently, an inactivated vaccine has been widely used with encouraging results as a prophylactic agent against COVID-19 infection, which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its variants. However, in vitro SARS-CoV-2 vaccine-specific immune features remain elusive, hindering the promotion of a third dose of the vaccine. Here, we present a detailed in vitro immune cellular response and large-scale multi-omics analysis for peripheral blood mononuclear cells (PBMCs) from participants vaccinated with CoronaVac (Sinovac Life Sciences, Beijing, China) and recovered participants from COVID-19. The mean titers of SARS-CoV-2 serum-neutralizing antibodies were significantly increased after the boosting immunization (Day 45) compared to the unimmunized state. We observed that type-1 helper T cells (Th1) tended to dominate after the first dose of vaccine, while humoral immune responses became dominant after the second dose due to the activation of type-2 helper T cell (Th2), memory B cells, and plasmablasts. T follicular helper cells (Tfh) involved in antibody production were activated after the first dose and were maintained for the observed time points. Single-cell RNA sequencing of PBMCs revealed specific changes in cell compositions and gene expression in immunized participants. Multi-omics analysis also demonstrated that CoronaVac-specific serum proteins, plasma metabolites, and plasma lipid changes were skewed to those changes in convalescent patients. Collectively, we provide a comprehensive understanding of CoronaVac-specific in vitro immune features.

5.
J Sci Educ Technol ; 31(4): 461-472, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35730013

RESUMO

As a result of COVID-19, various forms of education and teaching are moving online. However, the notion of an online STEM camp is still in its beginnings, and there is little relevant research and experience in this context. At the beginning of April 2021, the research team launched an online STEM charity camp with the theme of "Shen Nong Tastes Herbs." Participants included 113 third- and fourth-grade primary school students ranging from 8 to 12 years of age from four schools in Karamay, Xinjiang Uygur Autonomous Region with weak educational capabilities. The camp lasted for 3 days and included 7 activities, while remote teaching was accomplished through Dingtalk. Pre- and post-test questionnaires and interviews were used to explore the impact of this camp on students. We found that online STEM camps could improve students' self-efficacy, computational thinking, and task value, and there is a significant improvement in the self-efficacy (p = 0.000) and task value (p = 0.001) dimensions. In addition, students with high self-efficacy had higher scores in the other two dimensions. Finally, we summarized the experiences and gains of students and teachers and proposed suggestions for developing online camps based on this experience. [Table: see text]. Supplementary Information: The online version contains supplementary material available at 10.1007/s10956-022-09967-y.

6.
Environ Sci Pollut Res Int ; 29(34): 52263-52276, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35258731

RESUMO

As the political and technological innovation center of China, Beijing-Tianjin-Hebei urban agglomeration (BTHUA) is an important engine of national economic development. However, the BTHUA is faced with uneven industrial development and environmental pollution problems. Energy efficiency of the industrial sector, critical to energy conservation and environmental protection, is the key to achieving green economic transformation. For this reason, this study adopts the parametric meta-frontier approach to measure the industrial total-factor energy efficiency (TFEE) of the BTHUA, centering on the evaluation of regional technology gap ratio (TGR). Empirical results indicate that there are significant regional disparities of industrial TFEE in the BTHUA. In particular, industrial TFEE tends to be underestimated without considering technological heterogeneity in production technology. The TGRs of manufacturing cities, tourist cities, and the modernized metropolis (Beijing) are the highest among the region. On this basis, the influencing factors of industrial TFEE of the BTHUA are further accessed based on the fixed effects model and the Tobit model. This article verifies that the evaluation of TFEE in the BTHUA must take regional technological gap into account, and provides additional empirical evidence on how to promote coordinated regional industrial development and energy efficiency improvement.


Assuntos
Conservação de Recursos Energéticos , Eficiência , Indústrias , Tecnologia , Pequim , Desenvolvimento Econômico , Indústrias/normas , Tecnologia/normas
7.
Front Psychol ; 13: 1092848, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36687926

RESUMO

Teachers' engagement in online learning is a key factor in improving the effectiveness of online teacher training. This paper introduces a multimodal learning analytics approach that uses data on brain waves, eye movements and facial expressions to predict in-service teachers' engagement and learning outcomes in online synchronous training. This study analyzed to what extent the unimodal and multimodal data obtained from the in-service teachers (n = 53) predict their learning outcomes and engagement. The results show that models using facial expressions and eye movements data had the best predictive performance on learning outcomes. The performance varied on teachers' engagement: the multimodal model (integrating eye movements, facial expressions, and brain wave data) was best at predicting cognitive engagement and emotional engagement, while the one (integrating eye movements and facial expressions data) performed best at predicting behavioral engagement. At last, we applied the models to the four stages of online synchronous training and discussed changes in the level of teacher engagement. The work helps understand the value of multimodal data for predicting teachers' online learning process and promoting online teacher professional development.

8.
AAPS PharmSciTech ; 22(7): 245, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34611770

RESUMO

The aim of this article was to design a self-emulsifying drug delivery system (SEDDS) of loaded cepharanthine (CEP) to improve the oral bioavailability in rats. Based on the solubility determination and pseudo-ternary phase diagram, isopropyl palmitate (IPP) was chosen as the oil phase. Meanwhile, Cremophor RH40 and Macrogol 200 (PEG 200) were chosen as the emulsifier and co-emulsifier, respectively. This prescription was further optimized by using central composite design of response surface methodology. The optimized condition was CEP:IPP:Cremophor RH40:PEG 200=3.6:30.0:55.3:11.1 in mass ratio with maximum drug loading (36.21 mg/mL) and the minimum particle size (36.70 nm). The constructed CEP-SEDDS was characterized by dynamic light scattering, transmission electron microscopy, in vitro release and stability studies. The dissolution level of CEP-SEDDS was nearly 100% after 30 min in phosphate-buffered saline (PBS, pH 6.8) which was higher than that of the pure CEP (approximately 20%). In addition, in vivo pharmacokinetic study in rats showed that CEP-SEDDS dramatically improved bioavailability compared with active pharmaceutical ingredient (API) (the relative bioavailability was 203.46%). In this study, CEP-SEDDS was successfully prepared to enhance the oral bioavailability which might facilitate to increase its better clinical application. Graphical abstract.


Assuntos
Sistemas de Liberação de Medicamentos , Administração Oral , Animais , Benzilisoquinolinas , Disponibilidade Biológica , Emulsões , Ratos , Solubilidade
10.
Nano Lett ; 21(10): 4371-4380, 2021 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-33984236

RESUMO

Anticancer immunotherapy is hampered by poor immunogenicity and a profoundly immunosuppressive microenvironment in solid tumors and lymph nodes. Herein, sequential pH/redox-responsive nanoparticles (SRNs) are engineered to activate the immune microenvironment of tumor sites and lymph nodes. The two-modular SRNs could sequentially respond to the acidic tumor microenvironment and endosome compartments of dendritic cells (DCs) to precisely deliver doxorubicin (DOX) and imidazoquinolines (IMDQs). In the tumor microenvironment, released DOX triggers immunogenic cell death. In sentinel lymph nodes, the IMDQ nanoparticle module is dissociated in the acidic endosome compartment to specifically stimulate toll-like receptor 7/8 for DC maturation. Thus, the orchestrated nanoparticle system could enhance the infiltration of CD8α+ T cells in tumors and provoke a strong antitumor immune response toward primary and abscopal tumors in B16-OVA and CT26 tumor-bearing mice models. The cooperative self-assembled nanoparticle strategy provides a potential candidate of nanomedicine to advance the synergistic cancer chemo-immunotherapy.


Assuntos
Nanopartículas , Neoplasias , Animais , Linhagem Celular Tumoral , Doxorrubicina , Morte Celular Imunogênica , Imunoterapia , Camundongos , Microambiente Tumoral
11.
Int J Pharm ; 588: 119759, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-32800938

RESUMO

The purpose of this study is to improve in vitro dissolution and in vivo bioavailability of the poorly soluble drug cilostazol (CLT) through amorphous solid dispersion technology, and this study prepared a stable supersaturated drug-loaded system to improve the problem of high free energy and instability of traditional solid dispersions. The optimized formulation of the solid dispersion is CLT: Syloid®244FP: Kolliphor®P188 = 1:1.5:1.5 (CLT-SD), where the co-loading of Syloid®244FP and Kolliphor®P188 has the synergistic effect. Drug polymers interactions and drug morphology were estimated by the physicochemical characterization, including DSC XRD, SEM, TEM, FT-IR, and Specific area analysis. Optimized formulation kept most drug in an amorphous state without significant change in dissolution, which could be maintained for at least 1 year. The solid dispersion was further prepared into osmotic pump tablets for the purpose of the controlled-release of drugs. The bioavailability of the three preparations (CLT, CLT-SD, osmotic pump tablets) was evaluated in Beagle dogs, which results clarified that the oral bioavailability of CLT-SD improved as compared with the CLT powder and osmotic pump tablets achieved controlled-release of drugs. In conclusion, co-loading drugs with mesoporous silica and hydrophilic polymer compounds can be a guiding future modification method for delivering supersaturated drug loading systems.


Assuntos
Cilostazol , Polímeros , Dióxido de Silício , Animais , Disponibilidade Biológica , Cães , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Comprimidos
12.
AAPS PharmSciTech ; 19(5): 2195-2202, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29725902

RESUMO

In order to explore a novel high efficacy drug delivery system for membranous glomerulonephritis (MGN), a complex chronic inflammation, methylprednisolone bovine serum albumin nanoparticles (ME BSA NPs) were designed. The nanoparticles were prepared by desolvation-chemical crosslinking method and its physicochemical characterizations were conducted. The experimental MGN rat models induced by cationic bovine serum albumin were established by a modified Border's method and applied in the pharmacodynamics study of ME BSA NPs. The results showed that the particle size, particle dispersion index, and entrapment efficiency of ME BSA NPs were 131.1 ± 3.4 nm, 0.159 ± 0.036, and 71.51 ± 1.74%, respectively. In addition, the image of transmission electron microscopy showed that the ME BSA NPs were the relatively uniform spherical particles. In the in vivo pharmacodynamics study, compared with saline group and SOLU-MEDROL® group, that the ME BSA NPs group was significantly reduced the levels of 24 h urinary protein (P < 0.01) and serum creatinine (P < 0.05). Consequently, these outcomes indicated that the nanoparticles we studied were a promising drug delivery system for the MGN disease, and it may be also useful for other complex chronic inflammations.


Assuntos
Anti-Inflamatórios/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Glomerulonefrite Membranosa/tratamento farmacológico , Hemissuccinato de Metilprednisolona/administração & dosagem , Nanopartículas/administração & dosagem , Soroalbumina Bovina/toxicidade , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/metabolismo , Cátions , Bovinos , Portadores de Fármacos/administração & dosagem , Portadores de Fármacos/química , Portadores de Fármacos/metabolismo , Feminino , Glomerulonefrite Membranosa/induzido quimicamente , Glomerulonefrite Membranosa/metabolismo , Hemissuccinato de Metilprednisolona/química , Hemissuccinato de Metilprednisolona/metabolismo , Microscopia Eletrônica de Transmissão , Nanopartículas/química , Nanopartículas/metabolismo , Tamanho da Partícula , Ratos , Ratos Sprague-Dawley , Resultado do Tratamento
13.
J Pharm Sci ; 107(5): 1434-1442, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29291415

RESUMO

In this study, a bilayer osmotic pump tablet of flurbiprofen (FP) solid dispersions (SDs) was developed to increase the solubility of the poorly soluble drug and controlled drug release at a constant rate. Based on the investigation of thermodynamic properties the drug, the carrier, and the calculation of the solubility parameters, the FP-SD was prepared by hot-melt extrusion technique with the povidone (PVP) VA64 carrier. Then, central composite design-response surface methodology was used to evaluate the influence of factors on the responses. Consequently, PVP VA64 was selected as the carrier for preparing FP-SD. The results of differential scanning calorimetry and X-ray confirmed that FP in FP-SD was in an amorphous state. FTIR indicated that the intermolecular hydrogen bond probably formed between FP and PVP VA64 in FP-SD. Correlation of release profiles to zero-order kinetics was significant (R2 = 0.9939). The mathematical models had good predictability because the deviation was less than 1% between the predicted value and measured value. These results demonstrated that FP-SD osmotic pump tablets successfully increased the solubility of FP and controlled the release of FP at a constant rate.


Assuntos
Anti-Inflamatórios não Esteroides/administração & dosagem , Preparações de Ação Retardada/química , Flurbiprofeno/administração & dosagem , Pirrolidinas/química , Compostos de Vinila/química , Analgésicos/administração & dosagem , Analgésicos/química , Anti-Inflamatórios não Esteroides/química , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Flurbiprofeno/química , Osmose , Solubilidade , Comprimidos , Temperatura , Temperatura de Transição
14.
Protein Cell ; 8(3): 191-201, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27909985

RESUMO

Metastasis is the leading cause of death in breast cancer patients. However, the mechanisms underlying metastasis are not well understood and there is no effective treatment in the clinic. Here, we demonstrate that in MMTV-PyMT, a highly malignant spontaneous breast tumor model, IL-25 (also called IL-17E) was expressed by tumor-infiltrating CD4+ T cells and macrophages. An IL-25 neutralization antibody, while not affecting primary tumor growth, substantially reduced lung metastasis. Inhibition of IL-25 resulted in decreased type 2 T cells and macrophages in the primary tumor microenvironments, both reported to enhance breast tumor invasion and subsequent metastasis to the lung. Taken together, our data suggest IL-25 blockade as a novel treatment for metastatic breast tumor.


Assuntos
Anticorpos Antineoplásicos/farmacologia , Anticorpos Neutralizantes/farmacologia , Neoplasias da Mama , Interleucina-17 , Interleucinas , Neoplasias Mamárias Animais , Microambiente Tumoral , Animais , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/genética , Neoplasias da Mama/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/patologia , Feminino , Humanos , Interleucina-17/antagonistas & inibidores , Interleucina-17/genética , Interleucina-17/imunologia , Interleucinas/antagonistas & inibidores , Interleucinas/genética , Interleucinas/imunologia , Macrófagos/imunologia , Macrófagos/patologia , Neoplasias Mamárias Animais/tratamento farmacológico , Neoplasias Mamárias Animais/genética , Neoplasias Mamárias Animais/imunologia , Camundongos , Metástase Neoplásica , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
15.
Clin Cancer Res ; 19(6): 1476-86, 2013 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-23363817

RESUMO

PURPOSE: Targeting oncogenic receptors with antibodies has been thought to suppress tumor growth mainly by interrupting oncogenic signals. Recently, the essential role for adaptive immunity, and CD8(+) T cells in particular, has been established as a major factor for anti-HER2/neu-mediated tumor regression. However, the role of CD4(+) T cells is still being defined. The purpose of this study was to explore whether and to what extent CD4(+) T cells are involved in mediating the effects of anti-HER2/neu therapy. EXPERIMENTAL DESIGN: The role of CD4(+) T cells was examined using a transplant model of the rat HER2/neu-overexpressing cell line TUBO. Tumor-bearing mice were treated with anti-neu therapy in conjunction with CD4 depletion or CD40L blockade. The effects of CD4 depletion on the antitumor response were examined by tumor growth analysis and enzyme-linked immunospot (ELISPOT). RESULTS: In addition to CD8(+) T cells, CD4(+) T cells are also essential for anti-neu antibody-mediated tumor regression, but B cells are not required. The role for CD4(+) cells is necessary throughout anti-neu therapy and not limited to helping CD8(+) T cells. Expression of IFN-γ is necessary for anti-neu therapy and IFN-γ induces MHC-II expression in TUBO cells promoting direct recognition by CD4(+) T cells. Furthermore, intratumoral depletion of CD4(+) T cells or blockade of the activating cell-surface protein CD40L inhibits the antitumor response. CONCLUSIONS: This study reveals the essential role of CD4(+) T cell for anti-neu-mediated tumor regression.


Assuntos
Anticorpos/uso terapêutico , Imunoterapia , Neoplasias Mamárias Animais/terapia , Receptor ErbB-2/imunologia , Animais , Anticorpos/imunologia , Linfócitos B/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Humanos , Interferon gama/metabolismo , Neoplasias Mamárias Animais/imunologia , Neoplasias Mamárias Animais/patologia , Camundongos , Ratos , Receptor ErbB-2/antagonistas & inibidores
16.
Cancer Cell ; 18(2): 160-70, 2010 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-20708157

RESUMO

Anti-HER2/neu antibody therapy is reported to mediate tumor regression by interrupting oncogenic signals and/or inducing FcR-mediated cytotoxicity. Here, we demonstrate that the mechanisms of tumor regression by this therapy also require the adaptive immune response. Activation of innate immunity and T cells, initiated by antibody treatment, was necessary. Intriguingly, the addition of chemotherapeutic drugs, although capable of enhancing the reduction of tumor burden, could abrogate antibody-initiated immunity leading to decreased resistance to rechallenge or earlier relapse. Increased influx of both innate and adaptive immune cells into the tumor microenvironment by a selected immunotherapy further enhanced subsequent antibody-induced immunity, leading to increased tumor eradication and resistance to rechallenge. This study proposes a model and strategy for anti-HER2/neu antibody-mediated tumor clearance.


Assuntos
Imunidade Adaptativa , Anticorpos Monoclonais/uso terapêutico , Imunidade Inata , Receptor ErbB-2/imunologia , Animais , Anticorpos Monoclonais/imunologia , Humanos , Memória Imunológica , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Linfócitos T Citotóxicos/imunologia
17.
Cell Biol Int ; 31(11): 1353-8, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17587607

RESUMO

The aim of the study was to investigate the sensitivity of AHH-1 human lymphoblastoid cells to radiation and its relevance to intracellular events, specifically alteration in cellular energy-producing systems. AHH-1 human lymphoblastoid cells were irradiated with 6 Gy of gamma radiation, and then were collected at the indicated time points. Parallel studies were conducted to assess the effects of radiation on the cell proliferation and apoptotic index. Mitochondrial membrane potential (MMP) and reactive oxygen species (ROS) production were monitored. A marked decrease of cell viability was observed as early as 12 h postirradiation and fraction of apoptotic cells was highest at 24 h. Intracellular ROS generation measured with 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) appeared to be highest as early as 30 min postirradiation and resumed to normal level at 6 h. Unexpectedly, the fluorescence intensity of Rhodamine 123 for measuring MMP did not change during the first 3h after radiation and exhibited an aberrant increase at 6 h. The results suggest that AHH-1 cells are sensitive to radiation-induced apoptosis and ROS generation is an early phase in the apoptosis process. Moreover, the results might cast doubts on those studies using Rhodamine 123 which hypothesized that the fall in MMP is one of the early events of apoptosis.


Assuntos
Apoptose/efeitos da radiação , Caspases/metabolismo , Raios gama , Linfócitos/metabolismo , Potencial da Membrana Mitocondrial/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos da radiação , Humanos , Linfócitos/citologia , Linfócitos/efeitos da radiação , Mitocôndrias/metabolismo , Mitocôndrias/efeitos da radiação
18.
World J Gastroenterol ; 12(15): 2455-8, 2006 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-16688844

RESUMO

AIM: To investigate the changes of lymphocyte subpopulations, especially CD4(+)CD25(+) T regulatory cells in Smad3(-/-) mice. METHODS: Hematological changes and changes of lymphocyte subpopulations were detected in Smad3(-/-) mice using cell counter and flow cytometry, respectively, and compared to their littermate controls. RESULTS: The numbers of neutrophils and lymphocytes in peripheral blood were significantly increased in Smad3(-/-) mice compared to littermate controls. CD19(+) expressing cells in blood and spleen, and CD8(+) T cells in thymus were all markedly decreased in Smad3(-/-) mice. More important, Smad3(-/-) mice had an increased population of CD4(+)CD25(+) T cells in peripheral lymphoid tissues, including thymus, spleen, and lymph nodes. CONCLUSION: These observations suggest that the changes of lymphocyte subpopulations might play a role in susceptibility to inflammation of Smad3(-/-) mice.


Assuntos
Linfócitos T CD4-Positivos/imunologia , Proteína Smad3/deficiência , Animais , Inflamação/etiologia , Contagem de Leucócitos , Camundongos , Camundongos Knockout , Neutrófilos/imunologia , Receptores de Interleucina-2/metabolismo , Proteína Smad3/genética , Proteína Smad3/fisiologia , Subpopulações de Linfócitos T/imunologia , Fator de Crescimento Transformador beta/metabolismo
19.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 20(6): 750-3, 2004 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-15555453

RESUMO

AIM: To observe the relationship between apoptosis of mouse thymic lymphocytes and the expressions of bax, bcl-2 and bcl-X(L) after gamma-ray radiation with lethal dose and provide the basis for treatment of acute severe radiation sickness. METHODS: 250 cleaning-grade C57 mice were randomly divided into 6 groups and treated with 0, 6, 9, 12, 15 and 20 Gy of whole body single gamma-irradiation, respectivety. The mice were killed by dislocation and then the thymus and peripheral blood samples were taken at 1-28 days and 3-12 months after irradiation. The lymphocytic apoptosis was analyzed by TUNEL. The expressions of bax, bcl-2 and bcl-X(L) were detected by in situ hybridization and immunohistochemical staining. RESULTS: (1)Mouse peripheral leucocytes showed a transient elevation at 6 h after radiation and then decreased rapidly. The leucocyte's number reduced to minimal level at day 7 after 6 Gy gamma-irradiation and returned to basic normal value until one month after radiation. (2)24 h after irradiation the apoptotic rate of thymic lymphocytes increased swiftly, and apoptotic rate was positively correlated with radiation dose in the range of 6-12 Gy. There was no such a correlation after >/=15 Gy irradiation. (3)24 h after 6 Gy irradiation the apoptotic rate of thymic lymphocytes reached the maximal level. Afterwards it began to decrease, but still higher than that of control group even after 12 months. (4)3 h after 6 Gy radiation the expression of Bax protein in thymic lymphocytes increased immediately, and reached the highest value at 24 h. On the other hand, the expressions of Bcl-2 and Bcl-X(L) proteins reduced evidently at 3 h after radiation, reaching the lowest level at 24 h. Analysis of bax and bcl-2 mRNAs was concordant with the protein expression results. CONCLUSION: After 6-12 Gy gamma-ray irradiation, the apoptotic rate of thymic lymphocytes is positively correlated with the radiation doses, suggesting that apoptosis is a major way of thymic lymphocyte death after

Assuntos
Apoptose/efeitos da radiação , Linfócitos/efeitos da radiação , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Irradiação Corporal Total , Proteína X Associada a bcl-2/biossíntese , Proteína bcl-X/biossíntese , Animais , Radioisótopos de Cobalto , Feminino , Linfócitos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Proto-Oncogênicas c-bcl-2/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Doses de Radiação , Distribuição Aleatória , Timo/citologia , Timo/efeitos da radiação , Proteína X Associada a bcl-2/genética , Proteína bcl-X/genética
20.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 20(1): 39-41, 2004 Jan.
Artigo em Chinês | MEDLINE | ID: mdl-15182618

RESUMO

AIM: To explore the apoptotic characteristics and modulatory mechanism of human AHH-1 T lymphoblast induced by ionizing radiation and provide an experimental basis for preventing and treating immune damage in acute radiation sickness. METHODS: TdT-mediated dUTP nick end labeling (TUNEL) and May-Grunwald Giemsa (MGG) staining, MTT colorimetry and immunohistochemical staining were used to detect the T lymphocyte apoptosis, cell survival and the expressions of Bax, Bcl-XL and caspase-3 proteins. RESULTS: (1) Over a definite dose range, apoptotic rate of AHH-1T lymphocytes increased with the elevation of radiation doses, while the lymphocytic survival rate decreased sharply, both showing a good dose-effect relationship. (2) The expression of apoptosis-accelerating protein Bax enhanced obviously with the increase of radiation doses, while apoptosis-inhibiting protein Bcl-XL trended to persistent decline. (3)The activity of activated apoptosis-executing protein caspase-3 heightened significantly with increased radiation doses, which revealed a better corresponding relationship to apoptotic rate. CONCLUSION: A great number of apoptotic AHH-1 T cells may be one of major accounts for the lymphocyte rapid reduction and depressed organism immune function induced by irradiation. Bax, Bcl-XL and caspase-3 proteins play an important role in the regulation of radiation-induced T cell apoptosis.


Assuntos
Apoptose/efeitos da radiação , Linfócitos T/efeitos da radiação , Caspase 3 , Caspases/biossíntese , Relação Dose-Resposta à Radiação , Raios gama , Humanos , Proteínas Proto-Oncogênicas/análise , Proteínas Proto-Oncogênicas c-bcl-2/análise , Linfócitos T/citologia , Proteína X Associada a bcl-2 , Proteína bcl-X
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