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1.
Curr Med Imaging ; 19(12): 1436-1443, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36797600

RESUMO

BACKGROUND: Traditional radiography angles do not adequately reveal the shape and position of the right ventricular pacing electrode. OBJECTIVE: This study aimed to explore better radiography angles with the help of cardiac computed tomography (CT). METHODS: We analyzed the cardiac CT images of consecutive outpatients from 2018 to 2019. The right anterior oblique (RAO) 30° and the left anterior oblique (LAO) 40° were found to sufficiently display the shape and position of the right ventricular pacing electrode. RESULTS: A total of 214 consecutive outpatients were enrolled, whose average age was 55.0 ± 13.0 years, and 151 were male (70.6%). Through analyzing the cardiac CT images, the α angle (33.7° ± 6.1) and the γ angle (38.8° ± 8.0) were determined. Furthermore, we verified these angles in 48 patients after pacemaker implantation. The results showed that the ratio of the length of right ventricular electrode using the RAO α angle (≈30°) to the posterior-anterior position (PA position) was 1.099 ± 0.157 vs. 1.053 ± 0.182 (the ratio using the traditional RAO 45°) (P < 0.001). We observed that the relationship between the right ventricular active electrode and the ventricular septum was better identified using the LAO γ angle (≈40°) than the traditional 60° angle. CONCLUSION: With the help of cardiac CT, we found that RAO 30° could better show the shape and length of the right ventricular pacing electrode, and LAO 40° could better show the positional relationship between the pacing electrode and the ventricular septum.


Assuntos
Estimulação Cardíaca Artificial , Ventrículos do Coração , Humanos , Masculino , Adulto , Pessoa de Meia-Idade , Idoso , Feminino , Estimulação Cardíaca Artificial/métodos , Ventrículos do Coração/diagnóstico por imagem , Radiografia , Tomografia , Eletrodos
2.
Breed Sci ; 71(4): 484-490, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34912175

RESUMO

The soil-borne plasmodiophorid Polymyxa graminis is a vector for Barley yellow mosaic virus (BaYMV), which can severely damage barley plants. Although 22 disease resistance genes have been identified, only a few have been used for breeding virus-resistant cultivars. Recently, BaYMV strains capable of overcoming the effects of some of these genes have been detected. In this study, green fluorescent protein (GFP)-expressing BaYMV was constructed and used to examine viral dynamics in inoculated barley plants. Leaf inoculations resulted in higher infection rates than root or crown inoculations. Additionally, inoculations of some resistant cultivars produced infections that were similar to those observed in a field test. The results of this study indicate that the GFP-expressing virus is a useful tool for visualizing virus replication and dynamics, and for understanding resistance mechanisms.

3.
Front Med (Lausanne) ; 8: 640289, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34017841

RESUMO

Background: Patients with chronic obstructive pulmonary disease (COPD) are more susceptible to Aspergillus colonization or infection. Several studies have demonstrated that invasive pulmonary Aspergillosis (IPA) and Aspergillus hypersensitivity (AH) have a detrimental effect on COPD. However, it remains to be clarified whether Aspergillus colonization is associated with acute exacerbation of COPD (AECOPD). This study aimed to explore the impact of Aspergillus colonization in the lower respiratory tract on AECOPD. Method: Patients with Aspergillus colonization were identified from a retrospective cohort of hospitalized AECOPD from 2011 to 2016 in eight centers in Shanghai, China. The demographic information, conditions of the stable stage, clinical characteristics during hospitalization, and 1-year follow-up information after discharge were collected and compared to participants without fungi colonization. Result: Twenty-six hospitalized AECOPD patients with Aspergillus colonization and 72 controls were included in the final analysis after excluding patients with other fungi isolation and matching. The rates of recurrence of acute exacerbation within 90 days and 180 days after discharge in the patients with Aspergillus colonization were both significantly higher than that in the fungi negative patients (90 days: 19.2 vs. 4.2%, p = 0.029; 180 days: 23.1 vs. 4.2%, p = 0.010), and the all-cause mortality within 1 year was also higher (11.5 vs. 0.0%, p = 0.017). Multivariate logistic regression analysis showed that Aspergillus colonization was an independent risk factor for the recurrence of acute exacerbation within 90 days and 180 days (90 days: OR = 8.661, 95% CI: 1.496-50.159, p = 0.016; 180 days: OR =10.723, 95% CI: 1.936-59.394, p = 0.007). Conclusion: Aspergillus colonization may predict poor prognosis of AECOPD while leading to an increased risk of recurrent AECOPD in a short period.

4.
Front Cell Infect Microbiol ; 10: 538005, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33117725

RESUMO

Objective: To explore impact of Candida on the acute exacerbation of chronic obstructive pulmonary disease (AECOPD) outcome. Methods: A retrospective, multi-center, case-control study was performed. Patients hospitalized for AECOPD in 25 centers during Jan 2011-Dec 2016 were enrolled. Data were collected, including demographic information, conditions during the stable phase of COPD, clinical characteristics of AECOPD, and follow-up information within 1 year after discharge. Univariate analysis and binary logistic regression were applied, and p < 0.05 was regarded as significant. Results: Totally 1,103 patients were analyzed, with 644 lower respiratory airway (LTR) Candida positive cases and 459 Candida negative controls. Long-term prognosis was significantly different between Candida positive and negative group, including the recurrent AECOPD within 180 days (75.5 vs. 6.6%, p < 0.001) and mortality within 1 year (6.9 vs. 0.4%, p < 0.001). Univariate logistic analysis showed that LTR Candida isolation was related to higher recurrence rate of AECOPD within 180 days and mortality within 1 year. Binary logistic regression analysis demonstrated that LTR Candida isolation was independently associated with recurrence of AECOPD within 180 days. Conclusions: LTR Candida isolation was associated with worse long-term prognosis of AECOPD and independently related to higher risks of recurrent AECOPD within 180 days.


Assuntos
Candida , Doença Pulmonar Obstrutiva Crônica , Estudos de Casos e Controles , Humanos , Doença Pulmonar Obstrutiva Crônica/complicações , Recidiva , Estudos Retrospectivos
5.
Yao Xue Xue Bao ; 48(12): 1763-70, 2013 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-24689232

RESUMO

Because of the changed metabolic behaviors of cancer cells, tumor cells uptake a corresponding larger amount of glucose in physiological condition when compared with normal cells. And they were prone to metabolize glucose for generating energy in anaerobic glycolysis ways in order to grow quickly. Anaerobic glycolysis consumes more glucose than aerobic way when the same amount of energy is obtained, which also results in large demand of glucose in tumor cells. This review briefly describes therapy methods related to characteristic mentioned above, and summarizes the research progress of drugs, diagnostic reagents and carriers conjugated with glucose, glucose derivatives or other kinds of sugars for cancer targeting. Furthermore, typically relative research reports from 2012 till now were listed and analyzed.


Assuntos
Glucose/metabolismo , Glicoconjugados , Neoplasias/diagnóstico , Neoplasias/tratamento farmacológico , Animais , Antineoplásicos/uso terapêutico , Portadores de Fármacos , Metabolismo Energético , Glucose/análogos & derivados , Glucose/química , Glucose/uso terapêutico , Glicoconjugados/química , Glicoconjugados/uso terapêutico , Glicólise , Glicosídeos/química , Humanos , Ifosfamida/análogos & derivados , Ifosfamida/química , Ifosfamida/uso terapêutico , Neoplasias/metabolismo , Nitroimidazóis/química , Radiossensibilizantes/química
6.
Zhonghua Yi Xue Za Zhi ; 90(22): 1531-6, 2010 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-20973233

RESUMO

OBJECTIVE: To explore the role of bone marrow (BM) imprint in the diagnosis of hematological diseases. METHODS: Between January 2002 and June 2008, a total of 3024 cases with BM smears, imprints and sections conducted simultaneously were recruited. There were 1667 males and 1357 females with a median age of 55 years old (range: 7 to 92). The cellularity on imprint and smear was evaluated with the standard cellularity on BM section. With the integrative diagnosis (including all examinations and clinical outcomes) as the standard, the diagnostic accuracy of hematological diseases were compared between BM imprint, smear and section groups. Another 79 cases of lymphoma and 114 cases of plasma cell myeloma (PCM) were selected for a correlation analysis of tumor cell infiltration patterns. RESULTS: BM imprint contained hematopoietic and non-hematopoietic regions and cells retained integrated structure. The cellularity evaluation by imprint was superior to smear overall. In BM imprint group, the diagnostic accuracy for hypersplenism (n = 130), metastatic carcinoma (n = 67), refractory anemia with excess blasts, myeloproliferative neoplasm (n = 174), and PCM (n = 94) were better than smear group (96.9% vs 80.7%, 91.0% vs 76.1%, 92.6% vs 81.5%, 92.5% vs 76.4%, and 97.8% vs 92.6% respectively, all P < 0.05); And the diagnostic accuracy for megaloblastic anemia (n = 69), acute myeloid leukemia (n = 104), refractory cytopenia with unilineage dysplasia (n = 15), refractory cytopenia with multilineage dysplasia (n = 22), and lymphoplasmacytic lymphoma (n = 12) were higher than biopsy section group (100% vs 84.0%, 91.3% vs 74.0%, 86.7% vs 60.0%, 90. 9% vs 72.7%, and 66.6% vs 50.0% respectively, all P < 0.05); And the diagnostic accuracy for myelodysplastic/myeloproliferative neoplasm (n = 26) was higher than smear group (76.3%, P < 0.05) and biopsy section group (78.2%, P < 0.05). Excellent correlations existed between BM imprint and section of the patients with lymphoma or with PCM (r = 0.90, r = 0.78, both P < 0.05). CONCLUSIONS: BM imprint contains the characteristics of both smear and section. BM imprint is superior to smear for an evaluation of cellularity. And it is also better than section for an analysis of cytological changes.


Assuntos
Exame de Medula Óssea/métodos , Doenças Hematológicas/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
7.
Huan Jing Ke Xue ; 31(12): 2973-80, 2010 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-21360888

RESUMO

Genotoxicity of aldicarb and methomyl was explored. The aldicarb and methomyl were diluted by the deionized water respectively, and then five concentrations of aldicarb were generated as 0.002, 0.02, 0.2, 2, 20 microg/L, methomyl as 0.02, 0.2, 2, 20, 200 microg/L. The micronucleus of carp erythrocyte was counted by micronucleus test. The mutation of bacteria was assessed by Ames test. The DNA damage of human lymphocytes was tested by comet assay. The genotoxicity of aldicarb and methomyl was estimated by the three toxicology tests mentioned above. The results showed that, in the micronucleus test, both any concentration of two pesticides were not able to induce higher frequency of micronucleus in carp erythrocyte (p > 0.05). Under condition of metabolic inactivation, although the number of colony with back mutation in any concentration of two pesticides did not exceed the double number of those with spontaneous mutation, the revertants of TA97 strains in the aldicarb 2-20 microg/L and the methomyl 20-200 microg/L were (129.17 +/- 17.00), (129.50 +/- 18.28), (109.83 +/- 10.80) and (114.17 +/- 9.37) entries/plate, respectively, they were significantly greater than those in spontaneous mutation (p < 0.05, p < 0.01). In the methomyl 200 microg/L group, the revertants of TA100 and TA102 strains were (147.83 +/- 23.29) and (275.83 +/- 20.63) entries/plate, respectively, they are significantly higher than that of the control group under condition of metabolic activation (p < 0.05). In comet assay, both the high concentration groups of aldicarb and methomyl resulted in different degrees of DNA damage of human peripheral blood lymphocytes. Compared with deionized water group, all of three indexes of comet assay in the aldicarb 20 microg/L groups and the methomyl 200 microg/L groups were significantly higher (p < 0.01). Despite that both aldicarb and methomyl did not results in damaging chromosome carp erythrocyte and producing apparent mutagenicity, the effect of mutagenicity and DNA damage in human lymphocytes were observed in high concentration groups of both aldicarb and methomyl. Water polluted by aldicarb and methomyl may have the potential adverse effects on the environment and human health.


Assuntos
Aldicarb/toxicidade , Dano ao DNA/efeitos dos fármacos , Inseticidas/toxicidade , Metomil/toxicidade , Mutação/efeitos dos fármacos , Animais , Bactérias/genética , Carpas/genética , Ensaio Cometa , Eritrócitos/efeitos dos fármacos , Humanos , Linfócitos/efeitos dos fármacos , Testes para Micronúcleos , Testes de Mutagenicidade
8.
J Zhejiang Univ Sci B ; 9(6): 441-7, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18543396

RESUMO

OBJECTIVE: To determine fatty acid synthase (FAS) expression in human multiple myeloma and verify its potential as a therapeutic target in multiple myeloma. METHODS: FAS expression was determined by immunohistochemistry, reverse-transcription polymerase chain reaction (RT-PCR) and immunoblot analysis in bone marrow samples obtained from 27 patients with multiple myeloma (MM patients) and peripheral blood mononuclear cells (PBMCs) obtained from 12 healthy donors. In parallel, additional analyses were performed on 2 human multiple myeloma cell lines, U266 and RPMI8226. U266 cells were treated with cerulenin at various concentrations (5 to 320 microg/ml) for 24 h, and metabolic activity was measured by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Apoptosis was evaluated by dual Annexin V/PI (propidium iodide) labeling and flow cytometry (FCM) in U266 cells treated with 20 (g/ml cerulenin for 12 h or 24 h. RESULTS: By immunohistochemistry, we found that 19 of 27 bone marrow samples obtained from MM patients expressed significantly high levels of FAS. Similarly, by RT-PCR, 22 of 27 bone marrow samples obtained from MM patients, U266 and RPMI8226 showed FAS expression, whereas PBMC samples from 12 healthy donors did not express detectable level of FAS. FAS protein expression was confirmed by immunoblot analysis in 16 of 27 bone marrow samples obtained from MM patients, U266 and RPMI8226 cell lines, and no FAS protein expression was detected in PBMC samples from 12 healthy donors. U266 cells were highly sensitive to cerulenin treatment, with a dosage-related effect on metabolic activity, as a measure for cell proliferation. U266 cells treated with 20 microg/ml cerulenin for 12 and 24 h also showed early sign of apoptosis with 56.9% and 69.3% Annexin V(+)/PI(-) cells, and late apoptotic and necrotic cells with 3.2% and 17.6% Annexin V(+)/PI(+) cells. CONCLUSION: Increased FAS expression existed in multiple myeloma samples and human myeloma cell lines. Cerulenin greatly inhibited metabolic activity/cell proliferation of U266 cells and induced apoptosis, suggesting that FAS is an effective target for pharmacological therapy in human multiple myeloma.


Assuntos
Ácido Graxo Sintase Tipo I/metabolismo , Mieloma Múltiplo/enzimologia , Adulto , Idoso , Apoptose/efeitos dos fármacos , Sequência de Bases , Western Blotting , Estudos de Casos e Controles , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Cerulenina/farmacologia , Primers do DNA/genética , Inibidores Enzimáticos/farmacologia , Ácido Graxo Sintase Tipo I/antagonistas & inibidores , Ácido Graxo Sintase Tipo I/genética , Inibidores da Síntese de Ácidos Graxos/farmacologia , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA Neoplásico/genética , RNA Neoplásico/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
9.
Zhonghua Xue Ye Xue Za Zhi ; 28(4): 239-42, 2007 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-17877200

RESUMO

OBJECTIVE: To study the expression changes of apoptosis related genes induced by cerulenin in multiple myeloma cell line U266 and explore its molecular mechanism. METHODS: The expression changes of 96 apoptosis related genes were analyzed by superArray cDNA in U266 cells treated with cerulenin (20 microg/ml) for 12 h. Semi-quantitative RT-PCR was used to confirm the representative expression changes genes, Rip2, caspase 9 and TRAF2. RESULTS: After treated with cerulenin for 12 h, 44 apoptosis related genes expression in the U266 cells were changed, among which 41 were over 2 fold increase and 3 over 2 fold decrease. The expression of caspase 9 was increased markedly, indicating that mitochondria pathway played a key role in cerulenin inducing apoptosis and TRAF2 expression change suggested that nuclear factor (NF) participates in cerulenin inducing apoptosis. CONCLUSION: The death acceptor signaling pathway and the death acceptor non-dependence signaling pathway co-regulate cerulenin inducing apoptosis in U266 cells. Mitochondria pathway played the key role and nuclear factor (NF) participates in the apoptosis process.


Assuntos
Apoptose/efeitos dos fármacos , Cerulenina/farmacologia , Mieloma Múltiplo/metabolismo , Apoptose/genética , Linhagem Celular Tumoral , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Mieloma Múltiplo/genética , Mieloma Múltiplo/patologia , Transdução de Sinais/efeitos dos fármacos
10.
Vascul Pharmacol ; 47(2-3): 131-8, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17581794

RESUMO

Artesunate (ART), a semi-synthetic derivative of artemisinin extracted from the Chinese herb Artemisia annua, is a safe and effective antimalarial drug. In the present investigation, we analyzed the inhibitory effects of ART on angiogenesis and on VEGF production in chronic myeloid leukemia (CML) K562 cells in vitro and in vivo. In order to analyze the effect of ART on VEGF secretion in K562 cells, we examined the level of VEGF secreted in conditioned media (CM) by ELISA assay. The result showed that ART could decrease the VEGF level in CM of K562 cells, even at a lower concentration (2 micromol/l, P<0.01). The inhibitory effect of in vitro angiogenesis was tested on aortic sprouting in fibrin gel. ART could effectively suppress the stimulating angiogenic ability of CM by pretreated with K562 cells for 48 h in a time-dependent manner (days 3-14). The antiangiogenic effect of ART was further evaluated in vivo in chicken chorioallantoic membrane (CAM) neovascularization model. The result indicated that the stimulating angiogenic activity was decreased in response to the K562 cells treated with ART or the CM from K562 cells pretreated with ART in a dose-dependent manner (3-12 micromol/l). Furthermore, we analyzed the level of VEGF expression by western blot and detected the form of VEGF mRNA by RT-PCR in K562 cells. The experiments showed that ART could inhibit the VEGF expression, correlated well with the level of VEGF secreted in CM. These findings suggest that ART might present potential antileukemia effect as a treatment for CML therapy, or as an adjunct to standard chemotherapeutic regimens.


Assuntos
Inibidores da Angiogênese/farmacologia , Artemisininas/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Neovascularização Patológica , Sesquiterpenos/farmacologia , Fator A de Crescimento do Endotélio Vascular/efeitos dos fármacos , Inibidores da Angiogênese/administração & dosagem , Animais , Artemisia annua/química , Artemisininas/administração & dosagem , Artesunato , Embrião de Galinha , Relação Dose-Resposta a Droga , Regulação para Baixo , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Masculino , RNA Mensageiro/análise , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Sesquiterpenos/administração & dosagem , Fator A de Crescimento do Endotélio Vascular/metabolismo
11.
Zhonghua Xue Ye Xue Za Zhi ; 27(10): 675-7, 2006 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-17343199

RESUMO

OBJECTIVE: To determine whether fatty acid synthase (FAS) is expressed in human multiple myeloma( MM) cells and investigate the proliferation inhibition effect of fatty acid synthase inhibitor cerulenin on multiple myeloma cell line U266 and its mechanism. METHODS: FAS mRNA expression in human MM cell line U266, RPMI8226 cell was assayed by RT-PCR. The proliferation inhibition rate of U266 cells was assayed by MTr analysis. Cell apoptosis and cycle distribution were evaluated by flow cytometry (FCM). RESULTS: FAS mRNA was highly expressed in human multiple myeloma cell lines as compared with healthy donor PBMNCs. After U266 cells were treated with cerulenin (the concentrations from 5 microg/ml to 640 microg/ ml) for 24 h, the cell proliferation was markedly inhibited with a dose related manner, while the inhibition rate of human skin fibroblast cells were all lower than 30%. When U266 cells were treated with 20 pjg/ml cerulenin for 12 h and 24 h, the early apoptosis rate revealed by Annexin V/PI were 56. 9% and 69. 3% respectively, being higher than that of the blank controls (4. 3% and 1.8%, P < 0. 01). Cell cycle analysis showed it was blocked in S phase. Conclusion FAS is highly expressed in human MM. Cerulenin could induce apoptosis and inhibit proliferation of U266 cells. FAS might be a new potential target for multiple myeloma treatment.


Assuntos
Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Cerulenina/farmacologia , Ácido Graxo Sintases/antagonistas & inibidores , Mieloma Múltiplo/metabolismo , Relação Dose-Resposta a Droga , Ácido Graxo Sintases/biossíntese , Humanos , Mieloma Múltiplo/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Tumorais Cultivadas
12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 13(6): 1082-5, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16403285

RESUMO

To investigate the morphological changes of megakaryocytes with nuclear extrusion and nucleocytoplasmic separation, the morphological characteristics of megakaryocytes in peripheral blood films, bone marrow smears, and bone marrow biopsies from 4 newly diagnosed patients with primary myelofibrosis (PMF), myelodysplastic syndrome (MDS), myeloblastic leukemia with maturation (M(2)) and erythroleukemia (M(6)) were studied by using light microscope. The results showed that many kinds of dysmegakaryocytes were observed in bone marrow smears of 4 cases, while in case A (PMF) and case D (M(6)) micromegakaryocytes were ripped apart; in case B (MDS) and case C (M(2)) megakaryocytes were accompanied by nuclear extrusion or nucleocytoplasmic separation, and their bodies were large or giant, the part of nucleus separated from their body and little cytoplasm remained as micromegakaryocytes. The nucleocytoplasmic separation could be displayed by immunocytochemistry stain. It is concluded that the phenomenon of nuclear extrusion and nucleocytoplasmic separation in megakaryocytes suggested the process that dispersed multinuclear releasing towards surround or even totally left the cell body during the megakaryocyte maturation. It also showed that the micromegakaryocytes may be the result of nucleocytoplasmic separation or splittings from multi-separated nucleus.


Assuntos
Células da Medula Óssea/patologia , Doenças Hematológicas/sangue , Megacariócitos/patologia , Idoso , Núcleo Celular/patologia , Citoplasma/patologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Cancer Chemother Pharmacol ; 53(5): 423-32, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15132130

RESUMO

Dihydroartemisinin, a more water-soluble metabolite of artemisinin derivatives, is a safe and most effective antimalarial analog of artemisinin. In the present study, we investigated the antiangiogenic activity of dihydroartemisinin in vitro and in vivo, and investigated dihydroartemisinin-induced apoptosis in human umbilical vein endothelial cells (HUVEC). Dihydroartemisinin markedly reduced VEGF binding to its receptors on the surface of HUVEC. The expression levels of two major VEGF receptors, Flt-1 and KDR/flk-1, on HUVEC were lower following dihydroartemisinin treatment as shown by an immunocytochemical staining assay. The in vivo antiangiogenic activity was evaluated in the model of chicken chorioallantoic membrane (CAM) neovascularization. Dihydroartemisinin significantly inhibited CAM angiogenesis at low concentrations (5-30 nmol/100 microl per egg). We also investigated both qualitatively and quantitatively the induction of HUVEC apoptosis by dihydroartemisinin. A dose-related (5-80 microM) and time-dependent (6-36 h) increase in dihydroartemisinin-induced HUVEC apoptosis was observed by flow cytometry. Our results suggest that the antiangiogenic effect induced by dihydroartemisinin might occur by induction of cellular apoptosis and inhibition of expression of VEGF receptors. These findings and the known low toxicity of dihydroartemisinin indicate that it might be a promising candidate angiogenesis inhibitor.


Assuntos
Inibidores da Angiogênese/farmacologia , Antimaláricos/farmacologia , Artemisininas/farmacologia , Sesquiterpenos/farmacologia , Animais , Divisão Celular/efeitos dos fármacos , Células Cultivadas , Embrião de Galinha , Citometria de Fluxo , Humanos , Marcação In Situ das Extremidades Cortadas , Microscopia de Fluorescência , Receptores de Fatores de Crescimento do Endotélio Vascular/antagonistas & inibidores , Fator A de Crescimento do Endotélio Vascular/metabolismo
14.
Artigo em Inglês | MEDLINE | ID: mdl-12219203

RESUMO

Making use of the high expression efficiency of maltose-binding protein (MBP) in E. coli, the soluble and the inclusion body forms of MBP were purified to homogeneity by affinity chromatography and by denaturation, refolding and gel filtration respectively. After immunized Balb/C mice with two forms of MBP respectively, 5 clones for each antigen form were found to secrete monoclonal antibodies. The binding experiments showed that two antibodies obtained by the immunization with the refolded form of MBP had high affinity to the denatured MBP.

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