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Fabio Tavora Konstantin Shilo Irem H Ozbudak Jean M Przybocki Guanghua Wang William D Travis Teri J Franks 《Modern pathology》2007,20(9):995-999
Inflammatory myofibroblastic tumors are uncommon lesions composed of spindled myofibroblasts within a variable background of collagen and inflammatory cells. Although the true nature of these lesions is not fully elucidated, identification of consistent cytogenetic alterations in the anaplastic lymphoma kinase (ALK) gene suggests that they may be neoplastic. A small number of inflammatory myofibroblastic tumors have been reported to harbor human herpesvirus-8 (HHV-8), implicating the virus in its pathogenesis. In this study, 20 cases of pulmonary inflammatory myofibroblastic tumor were analyzed for the presence of HHV-8 with immunohistochemical and molecular methods. In all cases, antibodies to the latent nuclear antigen of the virus were applied. Four open reading frames (ORFs), including ORFs K2, 16, 26, and 72, were targeted utilizing real-time polymerase chain reaction (PCR). The cohort included 9 men and 11 women with a mean age of 37 years (range, 1-81). Microscopically, the tumors were composed of cytologically bland spindle cells with myofibroblastic differentiation. On immunohistochemical studies, 20% of cases (4/20) demonstrated diffuse cytoplasmic positivity with ALK. Immunohistochemical staining for the latent nuclear protein of the virus was negative in all cases (0/20). All tumors (100%, 20/20) tested with real-time PCR were negative for all four ORFs, whereas 100% (10/10) of positive control Kaposi sarcoma cases were positive. Her2 gene expression was present in all (20/20) inflammatory myofibroblastic tumors confirming the presence of amplifiable deoxyribonucleic acid in the tissue lysate. This study documents the absence of HHV-8 in pulmonary inflammatory myofibroblastic tumors, suggesting that further investigation is required to clarify the pathogenesis of this lesion. 相似文献
83.
Bronchiectasis, exacerbation indices, and inflammation in chronic obstructive pulmonary disease 总被引:2,自引:0,他引:2
Patel IS Vlahos I Wilkinson TM Lloyd-Owen SJ Donaldson GC Wilks M Reznek RH Wedzicha JA 《American journal of respiratory and critical care medicine》2004,170(4):400-407
Relationships between high-resolution computed tomography (HRCT) findings in chronic obstructive pulmonary disease (COPD) and bacterial colonization, airway inflammation, or exacerbation indices are unknown. Fifty-four patients with COPD (mean [SD]: age, 69 [7] years; FEV(1), 0.96 [0.33] L; FEV(1) [percent predicted], 38.1 [13.9]%; FEV(1)/forced vital capacity [percent predicted], 40.9 [11.8]%; arterial partial pressure of oxygen, 8.77 [1.11] kPa; history of smoking, 50.5 [33.5] smoking pack-years) underwent HRCT scans of the chest to quantify the presence and extent of bronchiectasis or emphysema. Exacerbation indices were determined from diary cards over 2 years. Quantitative sputum bacteriology and cytokine measurements were performed. Twenty-seven of 54 patients (50%) had bronchiectasis on HRCT, most frequently in the lower lobes (18 of 54, 33.3%). Patients with bronchiectasis had higher levels of airway inflammatory cytokines (p = 0.001). Lower lobe bronchiectasis was associated with lower airway bacterial colonization (p = 0.004), higher sputum interleukin-8 levels (p = 0.001), and longer symptom recovery time at exacerbation (p = 0.001). No relationship was seen between exacerbation frequency and HRCT changes. Evidence of moderate lower lobe bronchiectasis on HRCT is common in COPD and is associated with more severe COPD exacerbations, lower airway bacterial colonization, and increased sputum inflammatory markers. 相似文献
84.
BACKGROUND: Active relaxation develops as a result of sequestration of calcium into the sarcoplasmic reticulum, and is controlled mainly by sarcoplasmic reticulum calcium ATPase (SERCA) and phospholamban.Tumour necrosis factor-alpha (TNF-alpha) downregulates both of these proteins, so it may play a role in the development of abnormal relaxation. However, a possible relationship between TNF-alpha and diastolic dysfunction has not been sufficiently evaluated in vivo. We investigated whether circulating levels of TNF-alpha increased in patients with relaxation abnormality. METHODS: Forty hypertensive patients with normal left ventricular systolic function were enrolled in the study. Age-adjusted values of echocardiographically measured mitral inflow velocities, E-wave deceleration time and isovolemic relaxation time were used to define normal and abnormal relaxation. Twenty of the patients (mean age 59.2 +/- 10.6) had a relaxation abnormality (group I), and the twenty other patients (mean age 45.9 +/- 7.9) had a normal diastolic function (group II). TNF-alpha levels were measured by ELISA. RESULTS: There were no significant differences between the two groups in terms of interventricular septal thickness, posterior wall thickness, left ventricular mass, ejection fraction, plasma creatinin level, and medication. Patients with a relaxation abnormality were older than those with a normal diastolic function (p < 0.001). TNF-alpha levels were similar in both groups (62.1 +/- 46.0 pg/ml for group I, and 48.7 +/- 51.4 pg/ml for group II, p = 0.089). CONCLUSION: In this preliminary study, we demonstrated that TNF-alpha levels did not increase in patients with a relaxation abnormality. However, we think that a possible relationship between TNF-alpha and diastolic dysfunction should be clarified by further studies involving a larger number of patients with a wider spectrum of diastolic dysfunction. 相似文献
85.
A new indole alkaloid, galanthindole, was isolated from Galanthus plicatus ssp. byzantinus (Amaryllidaceae), a plant native to northwestern Turkey. Incorporating a non-fused indole ring, galanthindole may represent the prototype of a new subgroup of the Amaryllidaceae alkaloids. Two other bases, (+)-11-hydroxyvittatine and hordenine, are also reported from the same plant. 相似文献
86.
Basaran C Agildere AM Donmez FY Sevmis S Budakoglu I Karakayali H Haberal M 《AJR. American journal of roentgenology》2008,190(6):1527-1533
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