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da Silva ER Sly PD de Pereira MU Pinto LA Jones MH Pitrez PM Stein RT 《Pediatric pulmonology》2008,43(7):662-665
Non-atopic asthma is the predominant phenotype in non-affluent parts of Latin America. We recently reported that infestation with Ascaris lumbricoides increased the risk of non-atopic asthma in less affluent areas of Brazil but the mechanism is unclear. The present study was conducted to determine whether helminth infestation is associated with heightened bronchial responsiveness (BHR), a common finding in asthma. A random sample of 50 asthmatic and 50 non-asthmatic controls (mean age 10.1 years) were selected from a larger cohort (n = 1,011) without knowledge of their helminth infestation status. Three stool samples were collected from each child on different days and each sample was analyzed by the Kato-Katz method for quantitative determination of helminth eggs. Bronchial provocation tests were performed with inhaled 4.5% hypertonic saline using the ISAAC Phase II standardized protocol. There was no difference between the prevalence of positive BHR in the asthmatics (20.4%) compared with the controls (14.6%) (P = 1.0). Helminth infestation was detected in 24.0% of children, with A. lumbricoides being the most common. Children with high load infestation (>or=100 eggs/g) were five times more likely to have BHR than children with low load or no infestation. Despite the small sample size the results of the present study suggest that the link between high load helminth infestation and non-atopic asthma may be mediated via heightened bronchial responsiveness, possibly due to an inflammatory response to the pulmonary phase of the helminth life cycle. 相似文献
144.
Porrozzi R Teva A Amaral VF Santos da Costa MV Grimaldi G 《The American journal of tropical medicine and hygiene》2004,71(3):297-305
This study evaluates cross-immunity in rhesus monkeys (Macaca mulatta) previously infected with one species of Leishmania and have had self-cured disease or were cured by antimony-based therapy upon development of full-blown disease. We found that a self-healing cutaneous leishmaniasis (CL) following experimental infection with Leishmania (Leishmania) major induces significant protection for L. (L.) amazonensis and L. (Viannia) guyanensis, and was dependent on time of re-challenge by L (L.) amazonensis after animals had recovered from primary lesions, but lacked protection against L. (V.) braziliensis. In contrast, monkeys that recovered from L. (V.) braziliensis CL or L. (L.) chagasi visceral leishmaniasis following chemotherapeutic intervention were protected by challenge with L. (V.) braziliensis and L (L.) amazonensis. These findings indicate the relative variability in protection after self-cure or drug-cured experimental leishmaniasis to challenge by heterologous leishmanial parasites. Further studying the immune response may provide information regarding relevant factors influencing cross-protective immunity. 相似文献
145.
Mast cell recruitment after subcutaneous injection of RANTES in the sole of the rat paw 总被引:2,自引:0,他引:2
Pio Conti Marcella Reale Renato C. Barbacane Mario Felaco Alfredo Grilli & Theoharis C. Theoharides 《British journal of haematology》1998,103(3):798-803
Granulocyte colony-stimulating factor (G-CSF)-induced alteration of phosphoprotein during differentiation of HL-60 cells was studied. From the two-dimensional gel electrophoresis analysis of phosphoproteins, a 45 kD phosphoprotein in the cytosolic fraction of DMSO-pretreated HL-60 cells was rapidly dephosphorylated by the addition of G-CSF. This 45 kD phosphoprotein migrated into four or five spots between 4.5 and 5.5 pI. The dephosphorylation of 45 kD protein was observed within at least 10 min and reached a maximum at 60 min. Phosphoamino acid analysis showed that only serine residue of 45 kD phosphoprotein was phosphorylated, suggesting that G-CSF induced an activation of serine phosphatase. Furthermore, Staurosporine and calphostin C inhibited the phosphorylation of 45 kD protein, suggesting that protein kinase C or its downstream kinase(s) is involved in the phosphorylation of 45 kD protein. These results indicate that G-CSF causes dephosphorylation of a 45 kD cytosolic phosphoprotein which may play a role in signal transduction of G-CSF. 相似文献
146.
Experimental leptospirosis in marmoset monkeys (Callithrix jacchus): a new model for studies of severe pulmonary leptospirosis 总被引:3,自引:0,他引:3
Pereira MM Da Silva JJ Pinto MA Da Silva MF Machado MP Lenzi HL Marchevsky RS 《The American journal of tropical medicine and hygiene》2005,72(1):13-20
Experimental infection of marmoset monkeys (Callithrix jacchus) with Leptospira interrogans serovar Copenhageni showed microscopic patterns of tissue reactions comparable to those seen in the severe forms of human leptospirosis, including intra-alveolar hemorrhage. The most impressive microscopic changes were seen in the lung and kidney of animals killed at days 6 and 12 after inoculation. There were extensive and irregular areas of hemorrhage predominating around main bronchial branches or diffusely spread to the pulmonary parenchyma, as well as severe tubulointerstitial nephritis. Antibody response detected by the microscopic agglutination test was quantitatively similar to those seen in humans and paralleled severity of tissue lesions. The distribution of leptospires or antigenic debris in infected tissues was observed by immunofluorescence and confocal laser scanning microscopy. Large numbers of typical leptospires were seen in the lumen of proximal renal tubules. Positive reactions showing antigenic debris were closely associated with sites of tissue damage. 相似文献
147.
US9, a stable lysine-less herpes simplex virus 1 protein, is ubiquitinated before packaging into virions and associates with proteasomes
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Renato Brandimarti Bernard Roizman 《Proceedings of the National Academy of Sciences of the United States of America》1997,94(25):13973-13978
The US9 gene of herpes simplex virus 1 encodes a virion tegument protein with a predicted Mr of 10,000. Earlier studies have shown that the gene is not essential for viral replication in cells in culture. We report that (i) US9 forms in denaturing polyacrylamide gels multiple overlapping bands ranging in Mr from 12,000 to 25,000; (ii) the protein recovered from infected cells or purified virions reacts with anti-ubiquitin antibodies; (iii) autoradiographic images of US9 protein immunoprecipitated from cells infected with [35S]methionine-labeled virus indicate that the protein is stable for at least 4 h after entry into cells (the protein was also stable for at least 4 h after a 1-h labeling interval 12 h after infection); (iv) antibody to subunit 12 of proteasomes pulls down US9 protein from herpes simplex virus-infected cell lysates; and (v) the US9 gene is highly conserved among the members of the alpha subfamily of herpes viruses, and the US9 gene product lacks lysines. We conclude that US9 is a lysine-less, ubiquitinated protein that interacts with the ubiquitin-dependent pathway for degradation of proteins and that this function may be initiated at the time of entry of the virus into the cell. 相似文献
148.
Eduardo Vilar Gomez Bienvenido Gra Oramas EnriqueArus Soler Raimundo Llanio Navarro Caridad Ruenes Domech 《Liver international》2007,27(2):247-259
BACKGROUND: The pathogenesis of chronic hepatitis C (CHC) is associated to severe oxidative stress that leads to necro-inflammation and progression of fibrosis. Previous trials suggested that antioxidative therapy may have a beneficial effect. We evaluated the efficacy and safety of Viusid in combination with interferon alpha-2b (IFN alpha-2b) and ribavirin in patients with CHC. METHODS: We randomly assigned 100 patients, between October 2002 and December 2004, in two arms: IFN alpha-2b (5 MU on alternate days), ribavirin at a dose of 13 mg/kg daily and Viusid (three sachets daily) vs. IFN alpha-2b (5 MU on alternate days) and ribavirin at a dose of 13 mg/kg daily. Subjects were treated for 48 weeks and then followed for an additional 24 weeks. The primary end point was the histologic response (reduction of at least two points without fibrosis worsening in the total score on the Histological Activity Index). RESULTS: A significantly high proportion of patients who received combined therapy plus Viusid had a histologic response better than those patients who received IFN alpha-2b and ribavirin (57% vs. 37%, P=0.03). The patients with virologic response achieved the highest percentages of histologic response, irrespective of assigned treatment. Among non-responders, the highest reduction in the mean change from baseline score for necro-inflammatory activity (NA) and fibrosis (F) was reported in patients treated with Viusid [NA, -1.50 (Viusid), -1.20 (without Viusid); F, -0.31 (Viusid), 0.00 (without Viusid)]. Sustained normalization of serum alanine aminotransferase concentration was highest in the Viusid group compared with standard therapy (67% vs. 41%, P=0.009). The overall safety profile was similar in both groups, but interestingly, the anemia was less intense in the group with Viusid (P=0.04). CONCLUSIONS: Our results suggest that triple therapy with Viusid, IFN alpha-2b and ribavirin was well tolerated and may have a beneficial effect on histologic and biochemical variables. The intensity of anemia is reduced in patients treated with Viusid. 相似文献
149.
Chiappini B Minuti U Gregorini R Petrella L De Remigis F Giancola R Villani C Mazzola A 《The Journal of heart valve disease》2008,17(4):396-401
BACKGROUND AND AIM OF THE STUDY: Clinical and echocardiographic results were investigated to evaluate mitral valve repair in patients undergoing coronary artery bypass grafting (CABG) for ischemic cardiomyopathy (ICM) with moderately severe mitral regurgitation (MR). METHODS: A total of 78 patients (21 women, 57 men; mean age 69.5 +/- 7.8 years) with ischemic mitral regurgitation underwent mitral valve repair and CABG. The mean left ventricular ejection fraction (LVEF) was 42.4 +/- 12.4%. Among the patients, 19 (24.4%) had preoperative congestive heart failure (CHF). This surgery constituted a second such operation in five patients (6.4%). The MR was grade 3+ in 28 patients (35.9%) and 4+ in 50 (64.1%). The mean number of grafts was 3.6 per patient. RESULTS: Hospital mortality was 11.5% (n = 9). Risk factors for early mortality were preoperative NYHA class > or = III (p = 0.014), preoperative heart failure (p <0.001) and reoperation (p = 0.002). The five-year survival was 82.6 +/- 5.9%, and freedom from grade > or =2+ MR was 93.1 +/- 4.1%. Postoperatively, 66 patients (89.6%) were in NYHA class I and seven (9.4%) in class II, demonstrating a statistically significant improvement (p = 0.03). Late echocardiography showed a significant improvement in LVEF (from 42.4 +/- 12.4% to 51.7 +/- 10.9%; p = 0.01) and a reduction in pulmonary artery pressure (from 37.6 +/- 11.9 mmHg to 29.3 +/- 7.4 mmHg; p = 0.004). CONCLUSION: It is concluded that in patients with ICM, mitral valve repair combined with CABG provides a dramatic improvement in ejection fraction and in CHF, with excellent long-term survival, even in patients with a low LVEF. 相似文献
150.