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1.
Phys Rev Lett ; 129(24): 242502, 2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36563237

RESUMO

ß decay of proton-rich nuclei plays an important role in exploring isospin mixing. The ß decay of ^{26}P at the proton drip line is studied using double-sided silicon strip detectors operating in conjunction with high-purity germanium detectors. The T=2 isobaric analog state (IAS) at 13 055 keV and two new high-lying states at 13 380 and 11 912 keV in ^{26}Si are unambiguously identified through ß-delayed two-proton emission (ß2p). Angular correlations of two protons emitted from ^{26}Si excited states populated by ^{26}P ß decay are measured, which suggests that the two protons are emitted mainly sequentially. We report the first observation of a strongly isospin-mixed doublet that deexcites mainly via two-proton decay. The isospin mixing matrix element between the ^{26}Si IAS and the nearby 13 380-keV state is determined to be 130(21) keV, and this result represents the strongest mixing, highest excitation energy, and largest level spacing of a doublet ever observed in ß-decay experiments.

2.
AJNR Am J Neuroradiol ; 43(8): 1222-1227, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35863777

RESUMO

BACKGROUND AND PURPOSE: Percutaneous sacroplasty is a variation of percutaneous vertebroplasty that has gained attention as a therapeutic option for patients with painful sacral insufficiency fractures due to osteoporosis or metastases. Additionally, percutaneous sacroplasty can also be used to treat painful sacral metastases without a pathologic fracture. The purpose of this retrospective study was to compare the efficacy and safety of fluoroscopy-guided percutaneous sacroplasty alone versus percutaneous sacroplasty plus radiofrequency ablation for the treatment of painful sacral metastases. MATERIALS AND METHODS: For this retrospective study, 126 patients (with a total of 162 painful sacral metastases) were enrolled from October 2012 to February 2021 and assigned to receive either percutaneous sacroplasty plus radiofrequency ablation (n = 51, group A) or percutaneous sacroplasty alone (n = 75, group B). Four different approaches were used for percutaneous sacroplasty: transiliac, interpedicular, anterior-oblique, and posterior. The Visual Analog Scale, Oswestry Disability Index, and Karnofsky Performance Scale were used to evaluate outcomes. RESULTS: The Visual Analog Scale, Oswestry Disability Index, and Karnofsky Performance Scale scores showed significant improvement in both groups after treatment (P < .05). The overall pain relief rate was significantly better in group A than in group B (90% versus 76%, P = .032). There were no significant differences in the incidence of polymethylmethacrylate leakage between the 2 groups or among the 4 different approaches (P > .05). CONCLUSIONS: Both percutaneous sacroplasty alone and the combination of percutaneous sacroplasty and radiofrequency ablation are safe and effective for treatment of painful sacral metastases. The combination of percutaneous sacroplasty and radiofrequency ablation appears to be more effective than percutaneous sacroplasty alone.


Assuntos
Osteoporose , Fraturas da Coluna Vertebral , Humanos , Estudos Retrospectivos , Resultado do Tratamento , Cimentos Ósseos/uso terapêutico , Dor/tratamento farmacológico , Dor/etiologia , Dor/patologia , Osteoporose/complicações , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/cirurgia , Sacro/cirurgia , Sacro/lesões
3.
Phys Rev Lett ; 125(19): 192503, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33216609

RESUMO

ß-delayed one-proton emissions of ^{22}Si, the lightest nucleus with an isospin projection T_{z}=-3, are studied with a silicon array surrounded by high-purity germanium detectors. Properties of ß-decay branches and the reduced transition probabilities for the transitions to the low-lying states of ^{22}Al are determined. Compared to the mirror ß decay of ^{22}O, the largest value of mirror asymmetry in low-lying states by far, with δ=209(96), is found in the transition to the first 1^{+} excited state. Shell-model calculation with isospin-nonconserving forces, including the T=1, J=2, 3 interaction related to the s_{1/2} orbit that introduces explicitly the isospin-symmetry breaking force and describes the loosely bound nature of the wave functions of the s_{1/2} orbit, can reproduce the observed data well and consistently explain the observation that a large δ value occurs for the first but not for the second 1^{+} excited state of ^{22}Al. Our results, while supporting the proton-halo structure in ^{22}Al, might provide another means to identify halo nuclei.

4.
Eur Rev Med Pharmacol Sci ; 24(11): 6279-6287, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32572895

RESUMO

OBJECTIVE: The incidence of acute myocardial infarction (AMI) is increasing year by year, and it has become one of the diseases with the highest mortality in humans. MicroRNAs (miRNAs) are involved in the regulation of many diseases, including AMI. This study aims to investigate the function of miR-147 in myocardial infarction (MI) and its underlying mechanism of action. MATERIALS AND METHODS: Quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR) was used to detect miR-147, Bcl-2 mRNA, and Bax mRNA expressions. Enzyme-linked immunosorbent assay (ELISA) kits were used to detect the levels of inflammatory factors (TNF-α, IL-6, IL-ß) and lactate dehydrogenase (LDH). Besides, MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide] assay was performed to detect cell viability. Cell apoptosis was observed using terminal dexynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL). Moreover, echocardiography was utilized to measure cardiac function of rats. HIPK2 expression was detected by Western blot. RESULTS: MiR-147 expression was significantly decreased in rat MI model and H2O2 treated H9c2 cells. H2O2 treatment increased the expression of inflammatory factors in H9c2 cells and induced apoptosis, while such effects were inhibited by overexpression of miR-147. Overexpression of miR-147 reversed the decrease in Bcl-2 expression and the increase in Bax expression in H9c2 cells caused by H2O2. In addition, overexpression of miR-147 could improve cardiac function and reduce serum LDH levels in myocardial infarction rats. Through TargetScan, we found that HIPK2 might have a binding site for miR-147. Moreover, overexpression of miR-147 could inhibit the expression of HIPK2. CONCLUSIONS: In MI, miR-147 expression is decreased in the myocardium and overexpression of miR-147 can inhibit myocardial inflammation and apoptosis and improve cardiac function in rats via targeting HIPK2.


Assuntos
Apoptose , Inflamação/metabolismo , MicroRNAs/metabolismo , Infarto do Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Animais , Células Cultivadas , Inflamação/patologia , MicroRNAs/genética , Infarto do Miocárdio/patologia , Miócitos Cardíacos/patologia , Ratos , Ratos Sprague-Dawley
5.
Zhonghua Yi Xue Za Zhi ; 100(18): 1426-1431, 2020 May 12.
Artigo em Chinês | MEDLINE | ID: mdl-32392995

RESUMO

Objective: To investigate the prevalence of asthma among the elderly people in China and to analyze the clinical features, self-management and cognitive level of elderly asthma patients. Methods: According to the multi-stage random cluster sampling methods, a total of 164 215 subjects were visited by a questionnaire in the last epidemiology survey from eight provinces (Beijing, Shanghai, Guangdong, Liaoning, Henan, Shanxi, Jiangsu, Sichuan provinces) and seven regions (north, northeast, southern china, east, south, southwest and northwest) in China from February 2010 to August 2012. 2 034 were diagnosed as asthma. The elderly patients aged ≥65 years were selected from the 2 034 asthma patients. The clinical characteristics, comorbidities, the status of asthma control and self-management and insights of the disease in elderly asthma patients were analyzed. Results: Among the 2 034 asthma patients, 584 (28.7%) were elderly asthmatics aged ≥65 years old and 1 450 (71.3%) were<65 years old. In the elderly asthma group, Early-onset asthma accounted for 439 (75.2%) and 145 (24.8%) were late-onset. The common clinical manifestations of elderly asthma patients were: chest distress 395 (67.6%), wheezing 304 (52.1%), cough 298 (51.0%). Common comorbidities of elderly asthmatics were: chronic obstructive pulmonary disease 144 (24.7%), allergic rhinitis 122(20.9%), gastroesopheal reflux disease (GERD) 114(19.5%), allergic conjunctivitis 86 (14.7%), eczema 82 (14.0%), chronic bronchitis 76 (13.0%). The Asthma Control Test (ACT) scores of elderly asthmatics and non-elderly asthmatics were (18.5±3.2) and (21.7±3.4) respectively. There was a significant difference between the two groups (P=0.042). Of the elderly asthmatics, only 13 (2.2%) patients monitored daily using a peak flow meter. 93 (15.9%) patients aware that asthma was characterized by chronic airway inflammation. 64 (11.0%) asthmatics understood that the treatment goal. Conclusions: The clinical manifestations of elderly asthmatics are atypical, especially paroxysmal wheezing. Asthma in elderly people causes more comorbidities and mortality. The self-management and cognitive level of patients with asthma needs to be improved.


Assuntos
Asma , Autogestão , Idoso , China , Cognição , Humanos , Pessoa de Meia-Idade , Prevalência , Inquéritos e Questionários
6.
Zhonghua Yi Xue Za Zhi ; 100(14): 1106-1111, 2020 Apr 14.
Artigo em Chinês | MEDLINE | ID: mdl-32294877

RESUMO

Objective: To investigate the clinical characteristics and risk factors of severe bronchial asthma in Chinese people over 14 years old. Methods: According to the multi-stage random cluster sampling methods, a total of 164 215 subjects were visited by a questionnaire in the epidemiology survey from eight provinces (Beijing, Shanghai, Guangdong, Liaoning, Henan, Shanxi, Jiangsu, Sichuan provinces) located in seven regions (north, northeast, east, central China, south, southwest and northwest) of China from February 2010 to August 2012. A total of 2 034 were diagnosed as asthma. The clinical characteristics and related risk factors of patients with severe asthma in China were analyzed. Results: Among all asthma patients, 560 were newly diagnosed, accounting for 27.5% (560/2 034) and the percentage of previously confirmed patients was 72.5% (1 474/2 034). A total of 145 were eligible for severe asthma, accounting for 9.8% (145/1 474) of previously confirmed asthmatics and 7.1% (145/2 034) of all asthmatics. 83.5% (121/145) severe asthmatics had at least one trigger factor. Correlation analysis showed that the risk factors of severe asthma were: smoking (OR=1.543, 95%CI: 1.250-1.814), obesity (OR=2.186, 95%CI: 1.972-2.354), petting (OR=2.135, 95%CI: 1.904-2.283), combined with allergic rhinitis (OR=3.456, 95%CI: 2.721-4.326), gastroesophageal reflux disease (OR=1.842, 95%CI: 1.682-2.140), bronchiectasis (OR=1.665, 95%CI: 1.347-1.912) or chronic obstructive pulmonary disease (OR=1.312, 95%CI: 1.171-1.694). Conclusions: The most common comorbidities in severe asthmatics in China are allergic rhinitis and gastroesophageal reflux disease. The risk factors of severe asthma include obesity, allergic rhinitis, gastroesophageal reflux disease, chronic obstructive pulmonary disease, bronchiectasis, smoking and petting.


Assuntos
Asma , Adolescente , China , Humanos , Prevalência , Fatores de Risco , Índice de Gravidade de Doença , Inquéritos e Questionários
7.
Phys Rev Lett ; 122(19): 192503, 2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31144958

RESUMO

A new short-lived neutron-deficient isotope ^{220}Np was synthesized in the fusion-evaporation reaction ^{185}Re(^{40}Ar,5n)^{220}Np at the gas-filled recoil separator SHANS. Based on the measurement of the correlated α-decay chains, the decay properties of ^{220}Np with E_{α}=10040(18) keV and T_{1/2}=25_{-7}^{+14} µs were determined, which are in good agreement with theoretical predictions. From the new experimental results coupled with the recently reported α-decay data of ^{219,223}Np, the α-decay systematics for Np isotopes around N=126 was established, which allows us for the first time to test the robustness of the N=126 shell closure in Z=93 Np isotopes. The results also indicate that, in the region of nuclei with Z≥83, the proton drip line has been reached for all odd-Z isotopes up to Np.

8.
Zhonghua Jie He He Hu Xi Za Zhi ; 41(3): 191-195, 2018 Mar 12.
Artigo em Chinês | MEDLINE | ID: mdl-29518847

RESUMO

Objective: To evaluate the changes of asthma control, disease management and perception in recent years in China. Methods: We conducted 2 multi-center, cross-sectional surveys. Outpatient asthmatic patients from 10 cities in mainland China (2007-2008) and 30 central cities from 30 provinces in China (except Tibet)(2015-2016) were recruited respectively. Data of asthma control, disease management and perception from the 2 surveys were compared for 10 cities which took part in both of the 2 surveys. Chi-square test was used for comparison between groups. Results: The asthma control level improved from 28.7%(839/2 928) in 2007-2008 to 39.2%(533/1 361) in 2015-2016(P<0.01). The rate of emergency visits was 18.2%(248/1 362) in 2015-2016, which was lower than that in 2007-2008(33.9%, 1 032/3 044)(P<0.01). The rate of peak flow meter (PFM) usage was 17.9%(244/1 360) in 2015-2016, which was slightly lower than the PFM usage rate in 2007-2008(21.8%, 660/3 030)(P=0.004). 56.0%(763/1 362) of the patients used inhaled corticosteroid (ICS) + formoterol to control asthma when asthma symptoms deteriorated in 2015-2016, which was higher than the result of 2007-2008(31.8%, 803/2 524)(P<0.01). 71.1%(968/1 361) of the patients in 2015-2016 had a right perception on disease nature, while the result in 2007-2008 was 63.3%(1 889/2 986)(P<0.01). 61.6%(839/1 362) of the patients in 2015-2016 had a right perception on medication choice on daily-use first-line medication for chronic asthma, while the result in 2007-2008 was 51.0%(1 500/2 942)(P<0.01). Conclusion: The current level of asthma control and disease perception in China improved significantly in recent years, while the rate of PFM usage showed no significant improvement. Asthma action plan including PFM monitoring and asthma self-management should be further promoted nationwide.


Assuntos
Corticosteroides , Asma , China , Estudos Transversais , Gerenciamento Clínico , Humanos
9.
Zhonghua Nei Ke Za Zhi ; 56(7): 485-489, 2017 Jul 01.
Artigo em Chinês | MEDLINE | ID: mdl-28693055

RESUMO

Objective: To study the relationship between bronchial asthma and smoking status in Chinese people. Methods: Asthma epidemiological survey and stratified-cluster-random method survey were performed in residents over 14 years in 8 provinces (cities) of China from February 2010 to August 2012. Asthma was diagnosed based upon case history, clinical signs and lung function test. Smoking status was investigated by questionnaire. Results: Sampling population was 180 099 and 164 215 were valid. A total of 2 034 subjects were diagnosed as asthma including 79 692 men and 84 523 women. The overall prevalence rate of asthma was 1.24% (2 034/164 215). Smokers were 23.8% (39 137/164 215) in the whole population. Smokers were 34.5% (702/2 034) in asthmatic patients, compared with 23.7% (38 435/162 181) in no-asthmatic population. The incidence of asthma was 1.79% and 1.06% in smokers and non-smokers respectively (P<0.001), suggesting that OR of smoking was 1.70 (95% CI 1.55-1.86, P<0.001). According to asthma control test (ACT) score, the level of asthma control in non smoking group was higher than that in smoking group(43.2% vs 35.3%). The times of hospitalization due to acute exacerbations(0.51 vs 0.41 events/person/year), total hospitalization rate(27.35% vs 20.12%), annual emergency room visits (0.80 vs 0.60 events/person/year) and emergency room visit rate (31.77% vs 24.47%) were all much higher in smoking asthmatic patients than those in non smoking asthmatic patients, indicating that the level of asthma control in smoking patients was significantly worse than in non smoking patients. Conclusions: The smoking rate in Chinese people over 14 years is still high. The prevalence rate of asthma in smokers is significantly higher than that of non-smokers. The level of asthma control in smokers is significantly worse than that in non smokers.


Assuntos
Asma/epidemiologia , Fumar/epidemiologia , Adulto , Idoso , Povo Asiático , Asma/diagnóstico , China/epidemiologia , Cidades , Feminino , Hospitalização , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Médicos , Prevalência , Distribuição por Sexo , Inquéritos e Questionários
10.
Zhonghua Nei Ke Za Zhi ; 56(7): 546-557, 2017 Jul 01.
Artigo em Chinês | MEDLINE | ID: mdl-28693067

RESUMO

Important/potential value of macrolides has been proved in the management of chronic respiratory diseases by increasing basic and clinical trials.Through three face-to-face discussions, 10 experts examined important data and drafted this consensus related to macrolides: (1) mechanism of non-antiinfective effects; (2) clinical use in chronic respiratory diseases; (3) cautions of long-term use.The mechanism out of non-antiinfective effects includes anti-inflammatory effect, modifying airway secretion, immune-regulation related to antibacterial effect, corticoid saving effect and anti-viral effect.The efficacy of long-term use of low-dose macrolides is definitely confirmed in diffuse panbronchiolitis, chronic rhinosinusitis. It is considerably used in bronchiectasia, cystic fibrosis, severe asthma and chronic obstructive pulmonary disease. Further studies should be conducted in cryptogenic organizing pneumonia and respiratory viral infection. It should be paid attention to its possible adverse effects (including drug interactions, cardiac toxicity, ototoxicity and disturbance of intestinal flora) and drug resistance in long-term use.A Chinese consensus for non-antiinfective effects and clinical use of macrolides is developed for the first time, which aims to expand their rational use and the further research.


Assuntos
Anti-Infecciosos/uso terapêutico , Consenso , Prova Pericial , Macrolídeos/uso terapêutico , Guias de Prática Clínica como Assunto , Corticosteroides , Asma/tratamento farmacológico , Bronquiectasia/tratamento farmacológico , Bronquiolite , Doença Crônica/tratamento farmacológico , Infecções por Haemophilus , Humanos , Macrolídeos/efeitos adversos , Doença Pulmonar Obstrutiva Crônica/tratamento farmacológico
11.
Zhonghua Nei Ke Za Zhi ; 55(12): 917-921, 2016 Dec 01.
Artigo em Chinês | MEDLINE | ID: mdl-27916044

RESUMO

Objective: To analyze the prevalence of severe asthmain China. Methods: The epidemiological data was collected from 2 034 asthmatics who were diagnosed in the last epidemiological survey from 2009 to 2010 in 8 provinces. Results: According to the questionnaire survey, among the 2 034 patients, the previously diagnosed patients accounted for 72.47% (1 474/2 034) and the percentage of newly-diagnosed patients was 27.53% (560/2 034). In those 1 474 previously diagnosed asthmatics, 122 (8.28%) were classified into severe asthma, while 6.00% (122/2 034) of all asthmatics and 0.07% (122/164 215) of total respondents presented as severe cases. Statistically, there was no difference in the prevalence of severe patients between men and women. The morbidity rate of severe asthma was the lowest in the 21-30 year old group and the highest in 61-70 year old group (0.85% and 8.31% respectively). The difference among ages was statistically significant (χ2=18.791, P=0.005). In addition, the prevalence rates of severe asthma were also significantly diverged among patients with different education background(χ2=24.639, P<0.000 1). A negative relation was found between education level and the proportion of severe cases. Moreover, the morbidity of severe asthma in smoking patients and non-smoking patients were significantly different as well (χ2=7.447, P<0.05). Compared with asthma patients who do not smoke, smokers were more likely to suffer severe asthma (OR=1.663, 95% CI 1.150-2.404). Conclusions: The prevalence rate of severe asthma in China is similar to that in other countries.Elderly patients have higher risk of severe asthma. Smoking is considered as a risk factor for severe asthma.


Assuntos
Asma/epidemiologia , Idoso , Asma/diagnóstico , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Prevalência , Fatores de Risco , Fumar/efeitos adversos , Fumar/epidemiologia , Inquéritos e Questionários
12.
Int Arch Allergy Immunol ; 161(3): 243-51, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23548383

RESUMO

BACKGROUND: Calcium-activated chloride channels (CLCAs) have been found to be preferentially expressed on the secretory epithelium. They may play a pivotal role in mucous overproduction by bronchial goblet cells in asthma. It has been reported that the inhibition of CLCAs with niflumic acid could relieve the symptoms of asthma. However, niflumic acid has serious adverse effects. DNA vaccination is considered to be a promising strategy to treat allergic diseases such as asthma and dust mite allergy. METHODS: We constructed a vaccine encoding human CLCA1 (hCLCA1) and evaluated its effects on promoting antibodies against hCLCA1 and the related preventive function in a mouse model of asthma. RESULTS: Our results reveal that the induced hCLCA1 antibodies can be detected in the first 2 weeks after immunization with hCLCA1 plasmids (hCLCA1-p) by intramuscular injection and augmented gradually in the following several weeks. The autoantibodies against hCLCA1 induced by the DNA vaccine bound to three segments of the mouse CLCA3 (mCLCA3) protein, including the amino terminal (PepN), the carboxyl terminal (PepC) and the middle of the protein (PepM). In our study, mice immunized with hCLCA1-p developed fewer pathological changes compared with other control groups, including a remarkable reduction in the air pressure-time index of the trachea, the number of eosinophils and mast cells in the bronchoalveolar lavage fluid and the mRNA level of MUC5AC in goblet cells. CONCLUSION: Taken together, our results suggest that a DNA vaccine encoding the CLCA protein may have potential as a useful pharmacotherapy for asthma in the future.


Assuntos
Asma/tratamento farmacológico , Asma/imunologia , Canais de Cloreto/imunologia , Vacinas de DNA/imunologia , Vacinas de DNA/normas , Animais , Anticorpos/sangue , Western Blotting , Canais de Cloreto/genética , Modelos Animais de Doenças , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Segurança do Paciente , Reação em Cadeia da Polimerase
13.
Bull Entomol Res ; 100(2): 207-16, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19580687

RESUMO

A molecular phylogenetic study of the Drepanoidea based on the EF-1alpha sequences and combined EF-1alpha and COI sequences was carried out in order to infer higher classification at and above the subfamily level. The sample contained 14 taxa representing 13 genera recognized in the Drepanoidea. The results revealed that the Drepaninae, Thyatirinae and Cyclidiinae respectively form monophyletic groups. The sister relationship between the Drepaninae and the Thyatirinae was validated. The monophyly of the Cyclidiinae with the Drepaninae+Thyatirinae was supported robustly. Hypsomadius insignis and Oreta vatama within the traditional definition of the Drepaninae formed an individual clade with robust support (100%) and constitutes a sister relationship to a clade containing the rest of the Drepaninae in all the topologies, which means that the subfamily Oretinae of the Drepanidae should be restored. The family Drepanidae is divided into four subfamilies: Drepaninae, Oretinae, Thyatirinae and Cyclidiinae in this work. The family Epicopeiidae formed a monophyly with high bootstrap values. The result of combined analysis of EF-1alpha and COI showed that the Epicopeiidae have a closer phylogenetic relationship with the Geometridae than with the Drepanidae and belong to neither the Drepanoidea nor the Geometroidea.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/genética , Mariposas/classificação , Mariposas/genética , Fator 1 de Elongação de Peptídeos/genética , Filogenia , Animais , Dados de Sequência Molecular , Projetos Piloto
14.
Transplant Proc ; 40(5): 1700-5, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18589176

RESUMO

Previous studies have demonstrated that bone marrow-derived mesenchymal stem cell (MSC) engraftment attenuated lung injury in a model induced by bleomycin in mice. However, the mechanisms are not completely understood. The primary objective of the present study was to determine whether MSC engraftment can also protect lungs against bleomycin-induced injury in rats and to observe any beneficial effects of cytokines. Twelve hours after bleomycin (5 mg/kg) or phosphate-buffered saline was perfused into the trachea, 5x10(6) DAPI-labeled MSCs or DMEM-F12 were injected into the tail vein of rats. Two weeks later, MSCs labeled with DAPI were detected by pan-cytokeratin staining. The level of laminin and hyaluronan in bronchoalveolar lavage fluid was measured by radioimmunoassay. Collagen content in lung tissue was calculated by the hydroxyproline assay. TGF-beta1, PDGF-A, B, and IGF-I were measured by real-time PCR. It was observed that some MSCs positive for pan-cytokeratin staining, an indicator of alveolar epithelial cells, were present in injured lung tissue. Bleomycin injection increased the content of hydroxyproline in lung tissue, as well as laminin and hyaluronan in bronchoalveolar lavage fluid, markers for lung injury and fibrosis. However, these effects were attenuated by MSC treatment. Furthermore, the increased mRNA levels of TGF-beta1, PDGF-A, PDGF-B, and IGF-I following bleomycin injection were also significantly decreased by MSC treatment. These observations provided evidence that MSCs are still present in the lung 2 weeks after the initial MSC treatment in rats, as well as documented the beneficial effects of MSC engraftment against bleomycin-induced lung injury associated with changes in TGF-beta1, PDGF-A, PDGF-B, and IGF-I. These results may provide an experimental base for clinical therapy of pulmonary fibrosis in the future.


Assuntos
Bleomicina/toxicidade , Transplante de Células-Tronco Mesenquimais/métodos , Síndrome do Desconforto Respiratório/induzido quimicamente , Síndrome do Desconforto Respiratório/cirurgia , Animais , Células da Medula Óssea/citologia , Fêmur , Pulmão/citologia , Pulmão/patologia , Masculino , Ratos , Ratos Sprague-Dawley , Engenharia Tecidual/métodos
17.
Bull World Health Organ ; 79(7): 625-31, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11477965

RESUMO

OBJECTIVE: To test the efficacy of locally produced Vi vaccine over a time period of longer than one year. METHODS: A double-blinded, randomized field trial was performed in Guangxi Zhuang Autonomous Region in south-western China, using 30 micrograms doses of locally produced Vi. Enrolled subjects were 3-50 years of age, although the majority (92%) were school-aged children, who have the highest rate of typhoid fever in this setting. A total of 131,271 people were systematically allocated a single dose of 30 micrograms of Vi polysaccharide or saline placebo. The study population was followed for 19 months, with passive surveillance conducted in the Ministry of Health and the Regional Health and Anti-epidemic Centre (HAEC). Clinically suspected cases of typhoid fever were confirmed by blood culture, or by serological reaction with O-antigen (Widal tests). FINDINGS: After 19 months, there were 23 culture-confirmed cases of typhoid fever in the placebo group versus 7 cases in the Vi group (Protective efficacy (PE) = 69%; 95% CI = 28%, 87%). Most of the isolates were from school-aged children: 22 cases in the placebo group versus 6 in the Vi group (PE = 72%; 95% CI = 32%, 82%). No serious post-injection reactions were observed. The locally produced Vi polysaccharide vaccine showed levels of protective efficacy similar to those for Vi vaccine produced in industrial countries. CONCLUSION: The slightly higher dose of vaccine did not seem to alter efficacy significantly in China.


Assuntos
Antígenos de Bactérias/administração & dosagem , Polissacarídeos Bacterianos/administração & dosagem , Febre Tifoide/prevenção & controle , Vacinas Tíficas-Paratíficas/administração & dosagem , Adolescente , Adulto , Anticorpos Antibacterianos/sangue , Criança , Pré-Escolar , China , Método Duplo-Cego , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Placebos , Salmonella paratyphi A/isolamento & purificação , Salmonella typhi/isolamento & purificação , Resultado do Tratamento , Febre Tifoide/imunologia , Febre Tifoide/microbiologia , Vacinas Tíficas-Paratíficas/imunologia
18.
Oncogene ; 20(28): 3620-8, 2001 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-11439325

RESUMO

Chronic hepatitis B virus (HBV) infection and the integration of its X gene (HBx) are closely associated with the development of hepatocellular carcinoma (HCC). The integrated HBx frequently is truncated or contains point mutations. Previous studies indicated that these HBx mutants have a diminished co-transactivational activity. We have compared the effects of wild-type (wt) HBx and its naturally occurring mutants derived from human HCCs on transcriptional co-transactivation, apoptosis and interactive effects with p53. We demonstrated that overexpression of mutant, but not wt HBx, is defective in transcriptional co-transactivation of the NF-kappaB-driven luciferase reporter. By using a microinjection technique, the HBx mutants were shown to have an attenuated pro-apoptotic activity. This deficiency may be attributed to multiple mutations in the co-transactivation domain of HBx, that leads to decreased stability of the translated product. However, wt or mutant HBx bind to p53 in vitro and retain their ability to block p53-mediated apoptosis in vivo, which has been implicated as its major tumor suppressor function. The abrogation of p53-mediated apoptosis by integrated HBx mutants may provide a selective clonal advantage for preneoplastic or neoplastic hepatocytes and contribute to hepatocellular carcinogenesis.


Assuntos
Apoptose , Carcinoma Hepatocelular/virologia , Vírus da Hepatite B/metabolismo , Hepatite B Crônica/virologia , Neoplasias Hepáticas/virologia , Transativadores/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Sequência de Aminoácidos , Animais , Células COS , Linhagem Celular , Chlorocebus aethiops , Genes Reporter , Glutationa Transferase/metabolismo , Vírus da Hepatite B/genética , Humanos , Luciferases/genética , Dados de Sequência Molecular , Mutação , NF-kappa B/metabolismo , Biossíntese de Proteínas , Transativadores/genética , Ativação Transcricional , Proteínas Virais Reguladoras e Acessórias
19.
Oncogene ; 20(28): 3674-82, 2001 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-11439330

RESUMO

Hepatitis B virus (HBV) is a major risk factor for the development of hepatocellular carcinoma (HCC). HBV encodes the potentially oncogenic HBx protein, which mainly functions as a transcriptional co-activator involving in multiple gene deregulations. However, mechanisms underlying HBx-mediated oncogenicity remain unclear. To determine the role(s) of HBx in the early genesis of HCC, we utilized the NCI Oncochip microarray that contains 2208 human cDNA clones to examine the gene expression profiles in either freshly isolated normal primary adult human hepatocytes (Hhep) or an HCC cell line (SK-Hep-1) ecotopically expressing HBx via an adenoviral system. The gene expression profiles also were determined in liver samples from HBV-infected chronic active hepatitis patients when compared with normal liver samples. The microarray results were validated through Northern blot analysis of the expression of selected genes. Using reciprocally labeling hybridizations, scatterplot analysis of gene expression ratios in human primary hepatocytes expressing HBx demonstrates that microarrays are highly reproducible. The comparison of gene expression profiles between HBx-expressing primary hepatocytes and HBV-infected liver samples shows a consistent alteration of many cellular genes including a subset of oncogenes (such as c-myc and c-myb) and tumor suppressor genes (such as APC, p53, WAF1 and WT1). Furthermore, clustering algorithm analysis showed distinctive gene expression profiles in Hhep and SK-Hep-1 cells. Our findings are consistent with the hypothesis that the deregulation of cellular genes by oncogenic HBx may be an early event that favors hepatocyte proliferation during liver carcinogenesis.


Assuntos
Carcinoma Hepatocelular/genética , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Vírus da Hepatite B , Hepatite B Crônica/genética , Neoplasias Hepáticas/genética , Transativadores/biossíntese , Adulto , Northern Blotting/métodos , Carbocianinas , Corantes Fluorescentes , Congelamento , Expressão Gênica , Hepatite B Crônica/patologia , Hepatócitos/citologia , Humanos , Fígado/patologia , Análise de Sequência com Séries de Oligonucleotídeos , Coloração e Rotulagem/métodos , Transativadores/genética , Células Tumorais Cultivadas , Proteínas Virais Reguladoras e Acessórias
20.
J Biol Chem ; 276(25): 22797-803, 2001 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-11287420

RESUMO

The leucine-rich nuclear export signal (NES) is used to shuttle large cellular proteins from the nucleus to the cytoplasm. The nuclear export receptor Crm1 is essential in this process by recognizing the NES motif. Here, we show that the oncogenic hepatitis B virus (HBV) X protein (HBx) contains a functional NES motif. We found that the predominant cytoplasmic localization of HBx is sensitive to the drug leptomycin B (LMB), which specifically inactivates Crm1. Mutations at the two conserved leucine residues to alanine at the NES motif (L98A,L100A) resulted in a nuclear redistribution of HBx. A recombinant HBx protein binds to Crm1 in vitro. In addition, ectopic expression of HBx sequesters Crm1 in the cytoplasm. Furthermore, HBx activates NFkappaB by inducing its nuclear translocation in a NES-dependent manner. Abnormal cytoplasmic sequestration of Crm1, accompanied by a nuclear localization of NFkappaB, was also observed in hepatocytes from HBV-positive liver samples with chronic active hepatitis. We suggest that Crm1 may play a role in HBx-mediated liver carcinogenesis.


Assuntos
Proteínas de Transporte/metabolismo , Núcleo Celular/metabolismo , Carioferinas , Receptores Citoplasmáticos e Nucleares , Transativadores/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Proteínas de Transporte/fisiologia , Transformação Celular Neoplásica , Citoplasma/metabolismo , Primers do DNA , Vírus da Hepatite B/isolamento & purificação , Humanos , Fígado/metabolismo , Fígado/virologia , Neoplasias Hepáticas/patologia , NF-kappa B/metabolismo , Transporte Proteico , Homologia de Sequência de Aminoácidos , Transativadores/genética , Proteínas Virais Reguladoras e Acessórias , Proteína Exportina 1
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