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Pediatric asthma seriously endangers the well-being and health of children worldwide. Baicalin (BA) protects against diverse disorders, including asthma. Therefore, this study explored the mechanism of BA in pediatric asthma. The ovalbumin (OVA)-induced asthmatic mouse model was established to evaluate BA efficacy from aspects of oxidative stress, inflammation, blood cells in bronchoalveolar lavage fluid (BALF) and collagen deposition. Differentially expressed microRNAs (miRs) in BA-treated mice were analyzed. Effects of BA on PDGF-BB-induced smooth muscle cells (SMCs) were assessed. miR downstream mRNA and the related pathway were predicted and verified, and their effects on asthmatic mice were evaluated. BA effectively reversed OVA-induced oxidative stress and inflammation, as well as decreased the number of total cells, eosinophils and neutrophils in BALF, and collagen deposition. miR-103 was significantly upregulated after BA treatment. BA inhibited the abnormal proliferation of PDGF-BB-induced SMCs, which was prevented by miR-103 knockdown. miR-103 targeted TLR4 and regulated the extent of NF-κB phosphorylation. In vivo, miR-103 inhibition weakened the alleviating effects of BA on asthma, which was then reversed after silencing of TLR4. We highlighted that BA has the potency to halt the pediatric asthma progression via miR-103 upregulation and the TLR4/NF-κB axis inhibition.
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Asma , MicroRNAs , Animais , Asma/induzido quimicamente , Asma/tratamento farmacológico , Asma/genética , Becaplermina/metabolismo , Becaplermina/farmacologia , Líquido da Lavagem Broncoalveolar , Colágeno , Flavonoides , Humanos , Inflamação/genética , Pulmão/metabolismo , Camundongos , MicroRNAs/metabolismo , NF-kappa B/metabolismo , Ovalbumina , Receptor 4 Toll-Like/genéticaRESUMO
BACKGROUND: This paper tries to describe prevalence and patterns of antibiotics prescription and bacteria detection and sensitivity to antibiotics in rural China and implications for future antibiotic stewardship. METHODS: The study was implemented in one village clinic and one township health center in each of four rural residential areas in Anhui Province, China. It used mixed-methods comprising non-participative observations, exit-survey and microbiological study. Observations were conducted to record clinical diagnosis and antibiotic prescription. Semi-structured questionnaire survey was used to collect patient's sociodemographic information and symptoms. Sputum and throat swabs were collected for bacterial culture and susceptibility testing. RESULTS: A total of 1068 (51.0% male vs 49.0% female) patients completed the study with diagnosis of respiratory tract infection (326,30.5%), bronchitis/tracheitis (249,23.3%), pharyngitis (119,11.1%) and others (374, 35.0%). They provided 683 sputum and 385 throat swab specimens. Antibiotics were prescribed for 88% of the RTI patients. Of all the specimens tested, 329 (31%) were isolated with bacteria. The most frequently detected bacteria were K. pneumonia (24% in all specimens), H. influenza (16%), H. parainfluenzae (15%), P. aeruginosa (6%), S.aureus (5%), M. catarrhalis (3%) and S. pneumoniae (2%). CONCLUSIONS: The study establishes the feasibility of conducting microbiological testing outside Tier 2 and 3 hospitals in rural China. It reveals that prescription of antibiotics, especially broad-spectrum and combined antibiotics, is still very common and there is a clear need for stewardship programs aimed at both reducing the number of prescriptions and promoting single and narrow-spectrum antibiotics.
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Gestão de Antimicrobianos , Infecções Respiratórias , Instituições de Assistência Ambulatorial , Antibacterianos/uso terapêutico , China/epidemiologia , Feminino , Humanos , Masculino , Infecções Respiratórias/diagnóstico , Infecções Respiratórias/tratamento farmacológico , Infecções Respiratórias/epidemiologia , População RuralRESUMO
Inflammation and oxidative stress play crucial roles in the etiology of type 2 diabetes mellitus. In this study, we examined the anti-diabetic effects of triterpenoid saponins extracted from Stauntonia chinensis on stimulating glucose uptake by insulin-resistant human HepG2 cells. The results showed that saponin 6 significantly increased glucose uptake and glucose catabolism. Saponin 6 also enhanced the phosphorylation of AMP-activated protein kinase (AMPK) and activated the insulin receptor (IR)/insulin receptor substrate-1 (IRS-1)/phosphoinositide 3-kinase (PI3K)/Akt pathway. Therefore, our results suggest that saponins from S. chinensis improve glucose uptake and catabolism in hepatic cells by stimulating the AMPK and the IR/IRS-1/PI3K/Akt signaling pathways. The results also imply that saponins from S. chinensis can enhance glucose uptake and insulin sensitivity, representing a promising treatment for type 2 diabetes mellitus.
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Saponinas/toxicidade , Transdução de Sinais/efeitos dos fármacos , Estreptófitas/química , Triterpenos/química , Proteínas Quinases Ativadas por AMP/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Células Hep G2 , Hexoquinase/metabolismo , Humanos , Proteínas Substratos do Receptor de Insulina/metabolismo , Resistência à Insulina , Fosfatidilinositol 3-Quinases/metabolismo , Fosforilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Piruvato Quinase/metabolismo , Receptor de Insulina/metabolismo , Saponinas/química , Saponinas/isolamento & purificação , Estreptófitas/metabolismoRESUMO
Rice blast resistance (R) genes-mediated resistance response depends on various resistance-related genes involved in incompatible interactions. In this work, the expression profiles of innate rice immunity related genes were examined in the mediated resistance response of true/field resistance genes. Three sets of rice near-isogenic lines (NILs) were used: the resistant NILs carrying true resistance genes in the genetic background of the susceptible cultivar Nipponbare (NB), NB-Pib, NB-Pizt, NB-Pik and NB-Pita2; NILs bearing field resistance genes pi21 in the susceptible cultivar Aichiasahi (AA) AA-pi21, Kahei (KHR). The marker gene OsWRKY45 of salicylic acid (SA) signalling was upregulated in all tested cultivars. And, JAmyb (marker gene of jasmonic acid signalling) showed higher upregulation in the resistance lines with nucleotide-binding sites and leucine-rich repeat (NBS-LRR) R genes Pib, Pizt, Pik, Pita2 and Pikahei than in NB and KHS. SalT of abscisic acid (ABA) signalling may be involved in the R/Avr interaction, including Pizt, Pik, pi21 and Pikahei. However, SalT was shown to negatively regulate Pib/AvrPib interaction. OsPR1b and PBZ1 were differentially expressed and strongly activated at a later stage by 48 h post-inoculation. Interestingly, there was evidence that OsPR1b and PBZ1 played an important role in the pi21-mediated response. It was shown that OsRAR1 could be upregulated in the true resistance line NB-Pita2 and the field resistance line KHR, while OsSGT1 and OsHSP90 could be upregulated in all tested lines. The involvement of these genes illustrated the complexity of the downstream signalling pathways in the mediated resistance response of true/field resistance genes.
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Peroxydisulfate (PDS)-based advanced oxidation processes (AOPs) have been demonstrated to be an effective technology for the removal of refractory organic contaminants from the aquatic environment. Herein, a photothermal synergistic strategy is developed to realize the green activation of PDS under solar light irradiation. An innovative solar photothermal reaction system and its corresponding evaluation method are established. The results show that there is a synergistic effect between light and light-generated thermal effects on the activation of PDS for effectively removing fulvic acid (FA). The maximum degradation percentage of FA increases from 42.6% to 90.8% after introducing ZrC nanoparticles as photothermal materials. The maximum temperature of the whole system is up to 66.4 â after 120 min irradiation at 0.007 wt% solid content of ZrC, which is higher by 26.9% compared with that in the absence of ZrC nanoparticles. Furthermore, the underlying mechanism and PDS activation efficiency are deeply investigated. This work provides a viable strategy for directly using solar radiation to activate PDS for degrading refractory organic compounds, which creates a new avenue toward the utilization of solar energy for wastewater treatment.
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Águas Residuárias , Purificação da Água , Compostos Orgânicos , Oxirredução , Purificação da Água/métodosRESUMO
To explore the need for faculty development among Chinese medical educators. Leaders at each medical school in China were asked to complete a 123-item survey to identify interest in various topics and barriers and perceived benefits of participating in faculty development programs. Interest levels were high for all topics. Experience with Hospital Management and Research positively correlated with interest in learning more (p < 0.001). Ninety-two percent believe that international experiences are very or extremely important to medical educators' career advancement. Chinese medical education faculty members have a strong interest in faculty development programs.
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Educação Médica Continuada/métodos , Educação Médica/métodos , Docentes de Medicina , Adulto , Idoso , China , Feminino , Humanos , Cooperação Internacional , Masculino , Pessoa de Meia-Idade , Meio-Oeste dos Estados Unidos , Avaliação das Necessidades , Desenvolvimento de Pessoal/métodosRESUMO
The direct absorption solar collector (DASCs) with nanofluids can remarkably improve the utilization efficiency of solar energy. However, in the actual applications, the temperature distribution of the receiver is extremely uneven when the concentration of nanofluids is high or the receiver is deep. This makes the temperature of upper layer much higher than that of the lower layer, resulting in much heat loss to the surrounding by convection. Here, we propose a magnetic forced convection nanofluids absorption system, where an external rotating magnetic field is used to change the heat transfer mechanism of working fluids from traditional heat conduction to the thermal convection. It is found that the photothermal conversion efficiency of FeNi/C-EG nanofluids is up to 58.1% in this system, which is 22.7% higher than non-external rotating magnetic field when the nanofluids concentration is 50â¯ppm. Furthermore, the agglomeration of nanofluids can be effectively reduced by an external rotating magnetic field.
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Superprism effect is exhibited in one-dimensional thin film stacks due to their abnormal dispersion and anisotropy properties near the bandgap. Thin film Fabry-Perot filter (FPF) was designed and fabricated to realize this effect. Furthermore, the polychromatic light was operated at different incident angles onto the device to get more demultiplexing channels at different wavelength range. This means FPF, which fabricated low-costly and simply can be used as a tunable demultiplexing device. Meanwhile, distinguished with other researchers' arithmetic, transfer matrix method (TMM) with the Gaussian angular spectrum method was introduced to calculate more accurate spatial shift at different wavelength as well as to analysis beam splitting phenomena in FPF.
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OBJECTIVE: To analyze on the efficacy and toxicity of fludarabine and teniposide + mitoxantrone (MIT) regimens on treating refractory and relapsed acute lymphocytic leukemia in adult patients. METHODS: Teniposide 100 mg/d, 5-7 d, MIT 10 mg/d, 2 d and fludarabine regimens [Flu 30 mg/(m(2) . d), 3- 5 d, Cytarabine (Ara-c )1-2 g/(m(2) . d), 5 d; Flu 50 mg/d, 5 d, Ara-c 200 mg/d, 5 d, MIT 4 mg/d, 4 d] were used to treat 42 cases of adults with refractory and relapsed acute lymphocytic leukemia(ALL). G-CSF 5 microg/(kg . d) were used when WBC<1.0 x 10(9)/L. RESULTS: In both the regimens fludarabine and VM (teniposide + MIT), the complete remission (CR) rate was 45% versus 31.8% (P>0.05); the median neutropenia began 6 days after the regimens arresting and lasting 10 versus 7.5 days, P>0.05; thrombocytopenia begin at time of 10 versus 6.5 days (P<0.05) after the regimens arresting and lasting 6 versus 10 days (P>0.05). Fludarabine regimen had less non-haematological toxic effect than that of VM. CONCLUSION: Compared with VM, Fludarabine regimen was a very effective alternative treatment for CR induction in adult patients with refractory and relapsed ALL and low toxicity.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Adolescente , Adulto , Citarabina/administração & dosagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mitoxantrona/administração & dosagem , Recidiva Local de Neoplasia/tratamento farmacológico , Indução de Remissão , Estudos Retrospectivos , Teniposídeo/administração & dosagem , Resultado do Tratamento , Vidarabina/administração & dosagem , Vidarabina/análogos & derivadosRESUMO
OBJECTIVE: To define roles of B7-1 co-stimulation factor expressed in human malignant cell lines in mediating anti-tumor T cell immune responses. METHODS: Examining human leucocyte antigen (HLA) and B7 expressions on 8 human blood malignancies cell lines by flow cytometry. Transfecting B7-1 gene to B7-1 negative (B7(-)) Raji and B7(-) Jurkat cell lines by liposome, and comparing the potencies of blood malignant cell lines in the induction of T cell activation by examination of T cell cytokine mRNAs before and after transfection using semi-quantitative reverse transcription polymerase chain reaction (RT-PCR). RESULTS: High level of HLA I and II molecules were expressed in most human blood malignant cell lines examined, and the co-stimulatory factor B7-2 was also highly expressed. In contrast, another member of B7 family: B7-1 was either not expressed or very limitedly expressed in most of these hematopoietic malignant cell lines. Most importantly, transfection of B7-1 gene to B7(-). Raji and B7(-). Jurkat cell lines made these cell lines better antigen presenting cells for stimulation of anti-tumor T cell activation, which was demonstrated by up regulation of expression of T cell cytokines IL-2, IL-4 and INF-gamma mRNAs after incubation of these tumor cells with T cells for 24 h. CONCLUSIONS: B7 co-stimulation plays an important role in anti-tumor immunity. Transfection of B7-1 gene to the human hematopoietic malignant cell lines that are deficient in the B7-1 expression empowers their antigen presentation potency for activation of anti-tumor T cells. Our results suggested that repairing the deficiency of B7-1 co-stimulatory pathway in tumor cells might be a novel immunotherapeutic approach for human hematopoietic malignancies.
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Apresentação de Antígeno , Antígeno B7-1/fisiologia , Neoplasias Hematológicas/imunologia , Ativação Linfocitária , Linfócitos T/imunologia , Antígenos CD/análise , Antígeno B7-1/análise , Antígeno B7-2 , Citocinas/genética , Citometria de Fluxo , Antígeno HLA-DR7/fisiologia , Humanos , Células K562 , Glicoproteínas de Membrana/análise , RNA Mensageiro/análise , Transfecção , Células U937RESUMO
OBJECTIVE: To study diffuse alveolar hemorrhage (DAH) in patients with hematologic malignancies after chemotherapy and discuss the possible etiology and appropriate therapy. METHODS: Symptoms, physical examinations, laboratory examination, chest radiographs or computed tomographic (CT) scans, treatments and outcomes of two patients with acute lymphoblastic leukemia (ALL) and non-Hodgkin lymphoma (NHL) each after chemotherapy were presented. RESULTS: Both of the patients developed cough, progressive dyspnea, a drop of hemoglobin level, hypoxemia and widespread pulmonary infiltrate on chest radiographs or CT scans after chemotherapy. Moreover, case 1 (ALL) had high fever and bloody fluid drained from the intubation of mechanical ventilation, case 2 (NHL) developed continual hemoptysis. They were diagnosed as DAH and improved significantly after intermediate- or high-dose corticosteroid therapy. CONCLUSIONS: DAH is a rare fatal acute noninfectious pulmonary complication in patients with hematologic malignancies after chemotherapy. Early accurate diagnosis, identifying the underlying cause and appropriate treatment are critical for the management of DAH.
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Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Hemorragia/etiologia , Alvéolos Pulmonares , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Feminino , Hemorragia/tratamento farmacológico , Humanos , Linfoma não Hodgkin/tratamento farmacológico , Masculino , Metilprednisolona/uso terapêutico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológicoRESUMO
This study was aimed at measuring concentration of electrolytes, especially K+ in expressed prostatic secretion (EPS) and urine from patients with chronic prostatitis. The concentration of potassium, sodium, chloride, calcium in EPS and urine of 31 controls and 79 patients with prostatitis were measured and analyzed. There was no significant difference in the concentrations of potassium, sodium, chloride and calcium between the patients and the controls. Among the patients treated effectively, potassium concentration was 40.66 +/- 17.10 mmol/l before treatment and 33.42 +/- 17.27 mmol/l after treatment. While among the patients treated ineffectively, potassium concentration was measured as 37.57 +/- 16.93 mmol/l and 50.66 +/- 18.77 mmol/l before and after treatment respectively. The concentrations of electrolytes in prostatic fluid varied greatly between individuals. Potassium concentration in EPS decreased significantly after treatment among the patients with obvious treatment effectiveness, while increased among those who failed the treatment. EPS potassium concentration was also found to be lower in patients with pain than those without pain. No significant difference was found between the normal group and the no-pain patients.
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Eletrólitos/metabolismo , Próstata/metabolismo , Prostatite/metabolismo , Adolescente , Adulto , Secreções Corporais/metabolismo , Eletrólitos/urina , Humanos , Masculino , Pessoa de Meia-Idade , Dor/etiologia , Potássio/urina , Prostatite/complicações , Prostatite/urina , Resultado do TratamentoRESUMO
OBJECTIVE: To study the clinical characteristics and therapeutic outcome of Ph+ acute lymphoblastic leukemia (ALL). METHODS: Thirty previously untreated cases of Ph+ B-ALL were diagnosed in our institute. The patients were treated with combination chemotherapy of CODP +/- L regimen, Imatinib (400 approximately 600 mg/d) was continuously given to those who couldn't reach CR. Fourteen patients received allogeneic hematopoietic stem cell transplantation (allo-HSCT) after CR, while 16 received consolidation of intensive chemotherapy. RESULTS: Thirty (32.6%) of 92 ALL patients were diagnosed as Ph+ ALL, with a median age of 25.5 (14 - 60). Among them Ph+ as the sole anomaly was seen in 16 patients, and Ph+ with additional chromosome abnormalities in 14. Besides the B cell markers, 23 (76.7%) patients had CD34+ and 13 (43.3%) CD13+ and/or CD33+. Nineteen of the Ph+ ALL patients underwent molecular analysis; 13 (68.4%) expressed P190 and 6 (31.6%) P210. Increased WBC (> 30 x 10(9)/L) was found in 22/30 cases while WBC > 100 x 10(9)/L in 9/30 cases. The chemotherapy complete remission rate was 68.8% in patients with only Ph+ versus 28.6% in those with additional chromosome abnormalities. All seven refractory/relapsed patients reached CR with Imatinib therapy. The total complete remission rate was 73.3% in all Ph+ ALL patients. The median remission duration was shorter in patients with additional chromosome than in those with only Ph+ (1 vs 7 months, P < 0.05), and so was the survival period (7 vs 9 months, P > 0.05). The remission duration was significantly longer in patients received allo-HSCT than in those received chemotherapy only (8 vs 0.5 month, P < 0.05), and so was the survival period (12.5 vs 6 months, P < 0.05). CONCLUSION: Additional chromosome abnormalities negatively affect the prognosis and therapeutic effect of Ph+ ALL patients. Imatinib is effective for the induction therapy of Ph+ ALL. The survival period of patients who received allo-HSCT was obviously longer than those who received chemotherapy only.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Transplante de Células-Tronco Hematopoéticas/métodos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/cirurgia , Adolescente , Adulto , Terapia Combinada , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Prognóstico , Estudos Retrospectivos , Análise de Sobrevida , Resultado do Tratamento , Adulto JovemRESUMO
OBJECTIVE: To investigate the relationship between the biological features and the treatment efficacy and prognosis in acute myeloid leukemia subtype M2 (AML-M2) patients with chromosome 8 and 21 translocation. METHODS: By using Cox regression model and Kaplan-Meier analyses, prognostic factors in 54 cases of de novo adult AML with t(8;21) in our institute from 1990 to 2003 were retrospectively analyzed. RESULT: The complete remission (CR) rates were 81.9% for all M2 patients, 82.4% for patients with normal karyotype, 88.5% for patients with t(8;21) [P > 0.05 for normal karyotype vs t(8;21)], 100.0% for 28 patients with t(8;21) alone and 75.0% for 24 patients with additional chromosome abnormalities (P < 0.01). The actuarial 3 year overall survival(OS) was 26% for M2 patients with normal karyotype, 25% for patients with t(8;21) [P > 0.05 for normal karyotype vs t(8;21)], in whole t(8;21) group, 46.4% for patients with t(8;21) alone and 0% for patients with additional chromosome abnormalities (P < 0.01). Multivariate analysis of prognostic factors showed that chromosome abnormalities besides t(8;21) was the only factor affecting CR, disease-free survival (DFS) and OS. DFS of allogeneic hematopoietic stem cell transplantation (HSCT) and intermediate-dose cytarabine/high dose cytarabine (IDAC) groups were better than the group received routine dose cytarabine as postremission therapy (P < 0.01). CONCLUSION: AML with t(8;21) is not a single defined AML subset, and patients with additional chromosome abnormalities have a worse prognosis. HSCT and IDAC could improve the outcome. HSCT is the best choice for patients with high risks, especially with additional chromosome abnormalities.
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Leucemia Mieloide Aguda/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Cromossomos Humanos Par 21/genética , Cromossomos Humanos Par 8/genética , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/cirurgia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Translocação GenéticaRESUMO
To explore the cytogenetics and related clinical characteristics of adult acute leukemia with Philadelphia chromosome positive (Ph(+)AL), MIC classification by morphology, immunology and cytogenetics was used to retrospectively study 79 patients with Ph(+)AL hospitalized in the Institute of Hematology, People Hospital in Beijing from October 1991 to September 2003. The results showed that 6.9% cases were diagnosed as Ph(+)AL and classified into three subtypes: acute lymphoblastic leukemia (Ph(+)ALL) in 56 patients (18%), acute myeloid leukemia (Ph(+)AML) in 10 patients (1.2%) and mixed acute leukemia (Ph(+)MAL) in 13 patients. B-cell antigen expression was found in 52 out of 56 patients with Ph(+)ALL. 54.4% (43/79) patients had additional chromosome abnormalities including chromosome 7, double Ph and plus 8, etc. Complete remission (CR) rate of Ph(+)ALL and Ph(+)MAL was 57.0%, none of Ph(+)AML achieved CR. Median overall survival of Ph(+)ALL, Ph(+)MAL and Ph(+)AML were 10, 10 and 2.5 months respectively. It is concluded that Ph(+)AL has highly heterogeneity involving various differentiated stages of immature leukemic cells. Since the poor prognosis associated with this kind of AL, early diagnosis with MIC classification is a prerequisite to take more effective conditioning regimen and prospectively consideration of allogeneic stem cell transplantation to improve prognosis.
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Leucemia Mieloide Aguda/genética , Cromossomo Filadélfia , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adolescente , Adulto , Idoso , Antineoplásicos/uso terapêutico , Análise Citogenética , Feminino , Transplante de Células-Tronco Hematopoéticas , Humanos , Estimativa de Kaplan-Meier , Cariotipagem , Leucemia Mieloide Aguda/patologia , Leucemia Mieloide Aguda/terapia , Masculino , Pessoa de Meia-Idade , Leucemia-Linfoma Linfoblástico de Células Precursoras/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/terapia , Indução de RemissãoRESUMO
To detect effects of B7 co-stimulation on cytokines, especially on IL-2 mRNA and transcription factors NF-kappa B and AP-1, antiB7-1 McAb, antiB7-2 McAb and C TLA-4 Ig were added into mixture lymphocyte reaction (MLR) system to block B7/C D28 signal transduction, IL-2 mRNA and IL-4 mRNA were determined by using competitive PCR and IFN-gamma mRNA by using semi-quantitative PCR. MHC class II molecules and B7 transfectants were used to stimulate CD28(+) T cell, effects of B7 on NF-kappa B and AP-1 were detected by DNA-protein binding assay. The results showed that IL-2, IL-4 and IFN-gamma mRNA were significantly lower when blockade of B7-2 in MLR than blockade of B7-1. Synergistic effects could be seen with combination of two or three antibodies. One to six hours after MLR, tDR7 alone induced NF-kappa B binding activity; cotransfecting B7 no significantly difference at early time point. After 6 hours, induction of tDR7 was decreased whereas B7 prolonged the induction of NF-kappa B till 72 hours. tDR7 alone also upregulated AP-1 binding activity, on the contrary to NF-kappa B, co-transfecting B7-1 and B7-2 decreased AP-1 binding activity within 24 hours. But during 48 - 72 hours, B7 also prolonged the AP-1 binding activity. It is concluded that after MLR, B 7 increased IL-2 secretion by decreasing the degradation of IL-2 mRNA and upregulating IL-2 transcription factors. B7 also induced several kinds of cytokines secretion. Effects of B7-1 and B7-2 had no significant difference on transcription factors. It is suggested that the different functions between B7-1 and B7-2 maybe related to the difference of cell expression and kinetics. To study the molecular mechanism of B7 mediated T cell immune tolerance can help us to design a better clinic schema to prevent transplantation rejection and GVHD.
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Antígenos CD/fisiologia , Antígeno B7-1/fisiologia , Regulação da Expressão Gênica , Interleucina-2/genética , Glicoproteínas de Membrana/fisiologia , NF-kappa B/metabolismo , Fator de Transcrição AP-1/metabolismo , Células 3T3 , Animais , Antígeno B7-2 , Antígenos CD28/fisiologia , Humanos , Interferon gama/genética , Interleucina-4/genética , Teste de Cultura Mista de Linfócitos , Camundongos , RNA Mensageiro/análiseRESUMO
For the purpose of thrombocytopenia gene therapy, recombinant RevTet-On and pRevTRE/TPO retrovirus were packaged and transfected to NIH3T3 after selected with G418 and hygromycin, the two inserting recombinant retrovirus cell strain RevTet-On3T3/TPO were established. TPO expression was controlled and regulated by doxycydine (Dox). After using Dox to control the expression of TPO in RevTet-On3T3/TPO cells, the result showed that when Dox is added to the RevTet-On3T3/TPO cells, cell populations expressed TPO highly in the presence of 2 mg/L of Dox, and lowly in the absence of Dox. By using the RevTet-On gene expression system (the retrovirus vector RevTet-On regulation system to control the expression gene by Dox), it could modulate the expression of multiple genes by tetracyline and its derivatives. This system maybe provides a safe and efficacient way for the thrombocy to penia gene therapy.
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To study the significance of calcium in the apoptosis of HL-60 cells induced by VP-16, the technology of flow cytometry, confocal laser scanning microscopy and Western blot were used. The results showed that VP-16 could induced the apoptosis of HL-60 cells and transient increase of intracellular calcium concentration; EGTA [ethylene glycol-bis(2-aminoethyl)-N,N,N',N'-tetraacetic acid], that could combine the extracellular calcium, did not prevent the apoptosis of HL-60 cells. BAPTA-AM [1,2-bis(2-aminophenoxy) ethane-N,N,N',N'-tetraacetic acid tetrakis (acetoxy-methyl) ester], however, a chelating agent of intracellular calcium ions, could prevent apoptosis and the release of cytochrome C from HL-60 cells. It was concluded that the calcium plays an important role in apoptosis and the release of cytochrome C.
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A new apoptosis-related gene TFAR19 was recently cloned. A primary functional analysis indicates its role in the apoptotic process of TF-1 cells. To clarify TFAR19 was involved in which apoptotic pathway, the changes in TFAR19 expression were observed during the apoptotic processes of Jurkat cells induced with various methods: serum deprivation, VP-16 treatment and Fas McAb activation. Then TFAR19 expression in Jurkat cells was detected with flow cytometry and Western blot, and TFAR19 mRNA with RT-PCR. Our results showed that expression of TFAR19 in Jurkat cells was increased at 12 hours after serum deprivation, 2 hours after VP-16 treatment and 2 hours after Fas McAb activation, respectively. These observations suggested that TFAR19 was involved in the apoptotic process of Jurkat cells induced with serum deprivation, DNA destruction and death receptor activation. It might take effect in the early apoptotic process. TFAR19 is a participant of the "final common pathway" in the apoptotic pathway.