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61.
62.
Pepe C Foley S Shannon J Lemiere C Olivenstein R Ernst P Ludwig MS Martin JG Hamid Q 《The Journal of allergy and clinical immunology》2005,116(3):544-549
BACKGROUND: Airway remodeling in asthma comprises a range of structural changes. Several studies have suggested an association between these changes and disease severity. The relationship between the extent of remodeling and lung function is not well defined. OBJECTIVE: We sought to contrast the structural changes in the airways of well-defined groups of subjects with severe and moderate asthma and to correlate the extent of remodeling with disease severity. METHODS: Endobronchial biopsy specimens were obtained from 15 subjects with severe and 13 subjects with moderate asthma. Epithelial integrity, cell-layer areas, subepithelial fibrosis, and the distance between epithelial and airway smooth muscle (ASM) layers were measured by means of image analysis. Collagen was identified by using Van Giesen stain, and ASM was defined by using smooth muscle alpha-actin immunostaining. Specific immunostains were performed for the evaluation of RANTES, IL-8, and eotaxin expression as markers of ASM phenotype. RESULTS: ASM area was greater in subjects with severe (0.24+/- 0.03 mm(2)) than in subjects with moderate (0.05+/- 0.01 mm(2)) asthma (P<.001). The distance between the epithelial and ASM layers was less in the severe group (0.12+/- 0.01 mm) than in the moderate group (0.24+/- 0.02, P<.001). A trend toward greater subepithelial fibrosis in subjects with severe asthma did not reach statistical significance. IL-8 and eotaxin expression, but not RANTES expression, were increased in the ASM of subjects with severe asthma compared with in subjects with moderate asthma. CONCLUSION: Smooth muscle alteration is the key structural change that distinguishes severe from moderate asthma, and phenotypic change in ASM might contribute to the difficulty in obtaining adequate control in some subjects with severe asthma. 相似文献
63.
The Cbl family of ubiquitin ligases: critical negative regulators of tyrosine kinase signaling in the immune system 总被引:9,自引:0,他引:9
The Cbl family of proteins are evolutionarily conserved negative regulators of activated tyrosine kinase-coupled receptors. Antigen receptors are prominent targets of negative regulation by the Cbl family members, Cbl and Cbl-b, which proteins function as ubiquitin ligases. Cbl and Cbl-b contain substrate recognition domains that interact specifically with activated protein tyrosine kinases of the Src and Syk/ZAP-70 families. Cbl-mediated ubiquitination of these kinases leads to their degradation, resulting in attenuation of receptor signals. Cbl may also control activation-induced monoubiquitination of antigen receptors, thus facilitating their delivery to lysosomes for subsequent degradation. Finally, the interactions of Cbl proteins with downstream targets of tyrosine kinases, such as PI-3-kinase and Vav, could provide an additional mechanism to attenuate receptor signaling. By targeting multiple components of antigen receptor signaling for degradation, the Cbl protein family provides a critical mechanism to ensure an appropriate immune response. The hyperresponsiveness of Cbl(-/-) and Cbl-b(-/-) lymphocytes and the autoimmune phenotype of Cbl-b(-/-) mice lend strong support for this proposal. The ability to control early receptor signals through regulated protein degradation provides a novel paradigm of immunoregulation. 相似文献
64.
Hauber HP Gotfried M Newman K Danda R Servi RJ Christodoulopoulos P Hamid Q 《The Journal of allergy and clinical immunology》2003,112(1):58-63
BACKGROUND: New hydrofluoroalkane (HFA) formulations of glucocorticoids have been shown to effectively control asthma. HFA glucocorticoids are deposited across all sizes of airways, including the small ones. However, it is not clear whether they can suppress peripheral airway inflammation. OBJECTIVE: We sought to determine whether HFA-flunisolide could suppress peripheral inflammation in asthma. METHODS: Twelve patients with mild to moderate asthma received HFA-flunisolide for 6 weeks. Transbronchial and endobronchial biopsy specimens were obtained before and after treatment, and spirometry was performed. Changes in inflammatory cells (eosinophils, neutrophils, lymphocytes, macrophages, basophils) and IL-5 and eotaxin were measured by using immunocytochemistry and in situ hybridization. RESULTS: Lung function significantly improved after treatment (P <.05). HFA-flunisolide significantly reduced eosinophils, IL-5, and eotaxin in both peripheral and central airways (P <.01). Neutrophils significantly increased after treatment in peripheral and central airways (P <.05). The numbers of lymphocytes remained unchanged. CONCLUSIONS: These results show that HFA-flunisolide effectively suppressed eosinophilic inflammation in peripheral and central airways. These changes were accompanied by improvement in lung function. 相似文献
65.
Elias JA Homer RJ Hamid Q Lee CG 《The Journal of allergy and clinical immunology》2005,116(3):497-500
Chitin is the second most abundant biopolymer in nature, where it protects crustaceans, parasites, fungi, and other pathogens from the adverse effects of their environments, hosts, or both. Because chitin does not exist in mammals, it had been assumed that the chitinases that degrade it are also restricted to lower life forms. However, chitinases and chitinase-like proteins have recently been noted in mice and human subjects. The prototypic chitinase, acidic mammalian chitinase, was also noted to be induced during T(H)2 inflammation through an IL-13-dependent mechanism. It was also shown to play an important role in the pathogenesis of T(H)2 inflammation and IL-13 effector pathway activation and demonstrated to be expressed in an exaggerated fashion in human asthmatic tissues. The finding that chitinases contribute to host anti-parasite responses and asthmatic T(H)2 inflammation support the concept that asthma might be a parasite-independent anti-parasite response. 相似文献
66.
E M Krishchian N T Mandzhian N L Aslanian A A Chakhmakhchian Sh I Aleksanian 《Meditsinskaia tekhnika》1985,(6):35-38
The computer-aided (ES computer) system for acquisition, storage and sampling for any set of signs and processing of rhythm-based data is developed. The software is based on the operation system ES computer by using a time share system and a system for database control "Spektr". The informative database contains "The map of chronobiological examinations" and "The meteorologic map". 相似文献
67.
R. H. Bahar H. M. Abdel Dayem M. Mohammed M. Simo G. Ziada C. Costantinides A. R. Suhali 《European journal of nuclear medicine and molecular imaging》1987,12(11):542-545
Pulmonary hypertension (PH) produces strain followed by hypertrophy and later dilatation of the right ventricle (RV) and pulmonary artery. The signs and symptoms are nonspecific. There is a need for a noninvasive sensitive way to diagnose PH. The purpose of this study is to evaluate phase abnormalities in radionuclide MUGA studies of patients with referred diagnosis of PH. In a retrospective analysis of 44 patients who had a radionuclide multigated study (MUGA) and contrast ventriculography (CV), 19 had high mean pulmonary pressure (over 20 mmHg) and a high pulmonary vascular resistance index (over 2.0). In 15 patients, a delayed phase segment in the RV corresponding to the pulmonary infundibulum and pulmonary conus was noted The Pulmonary Tongue sign (PT), 12 had PH (True positive) and 3 did not (false positive) on CV. No PT was seen in the remaining 29 patients, only 7 of them had PH (False negative). The sensitivity, specificity and accuracy of the PT sign in detecting PH was 80%, 72% and 77% respectively. The number of patients was too small to calculate the correlation of the grade of PT with the severity of PH. We conclude that The Pulmonary Tongue sign on a MUGA study is clinically useful in detecting PH.This project is supported by research project MLNO13 and funded by research Council, Kuwait University 相似文献
68.
69.
Background activity of neighbouring neurons was recorded during chronic experiments in auditory cortex of unanesthetized unimmobilized cats. Functional connection between simultaneously observed neurons was estimated by cross-correlation of the spike trains. 20 pairs of neurons were studied. The most frequent type of interaction (50%) was a "shared excitatory input" from specific auditory afferents. Interaction of the "shared inhibitory input" type (5%) and complex patterns of interactions were found. No interaction between cells was observed in 10% of cases. Direct inhibitory influence of a cell on a neighbouring one was not found at all. Probable reasons of absence of direct inhibitory interactions between auditory cortical neurons are discussed. Low level of background activity in inhibitory neurons is regarded to be possible. 相似文献
70.
Ahmed Hassan Albelbeisi Ali Albelbeisi Abdel Hamid El Bilbeisi Mahmoud Taleb Amirhossein Takian Ali Akbari-Sari 《Ethiopian journal of health sciences》2021,31(1):73
BackgroundDespite the huge numbers of the universally produced and employed protocols, the adherence with them is still low to moderate in the healthcare settings. This study was employed to assess the attitudes of Palestinian healthcare professionals in Gaza Strip to health education and counseling on healthy behaviours protocol (WHO-PEN Protocol 2), for patients with non-communicable diseases in the Ministry of Health primary healthcare centers.MethodsThis cross-sectional study was conducted with a census sample of all governmental family physicians and nurses (n=175). The study questionnaire was developed based on Cabana theoretical framework. The Arabic version questionnaire was developed based on the cross-cultural adaptation framework. The psychometric properties of the Arabic version questionnaire was finally evaluated.ResultsThe psychometric properties of the Arabic version questionnaire showed good construct validity and internal consistency reliability. The overall adherence level to WHO-PEN Protocol 2 was 70.0, SD=6.9. The main perceived barriers were lack of incentive, patients'' factors, and lack of time. In general, most of healthcare professional respondents had a positive attitude toward the protocol, but this attitude was not predictor to protocol adherence.ConclusionThe good validity and reliability of the questionnaire can provide support for the accuracy of the study results. Varied implementation strategies targeting the major barriers derived from the study are extremely required for addressing the lack of incentives, patients'' factors and time constraints. 相似文献