1/3. Detection of chlamydia pneumoniae in unexplained pulmonary hypertension.The pathogenesis of primary pulmonary hypertension is still unclear. The case of a 68-yr-old female patient who complained of recurrent dizzy spells and collapses over a period of 6 weeks and died of global cardiac failure is presented. autopsy revealed severe pulmonary hypertension, slight chronic bronchitis, and bronchiolitis as well as intra-alveolar accumulation of macrophages. Chlamydiae were detected within the pulmonary arteries and in intramural and intra-alveolar macrophages by immunofluorescence, confocal laser scanning microscopy, scanning and transmission electron microscopy. Nested-polymerase chain reaction (PCR) and nonradioactive deoxyribonucleic acid (dna) hybridization of PCR products from pulmonary arteries revealed chlamydia pneumoniae dna. chlamydia pneumoniae has already been detected in atherosclerosis and in pulmonary emphysema. It can induce proliferation of smooth muscle cells. chlamydia pneumoniae might be relevant in aggravation of primary pulmonary hypertension and might perhaps be a trigger factor in some cases.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/3. Adenovirus pneumonia in lung transplant recipients.Although Adenovirus (ADV) pneumonia has been documented in bone marrow, kidney, and liver transplantation recipients, it has only been sporadically reported in lung transplantation recipients. Among our 308 lung transplantation recipients, we identified four who developed ADV pneumonia. Formalin-fixed paraffin-embedded biopsy and autopsy specimens on all cases were studied by routine histology, immunohistochemistry (IHC), and by in situ hybridization (ISH) for evidence of ADV, and the results were correlated with the patients' clinical progression. Three of the four patients were children, and all four had a progressive and rapidly fatal course within 45 days posttransplantation. The lungs showed necrotizing bronchocentric pneumonia with tendency to spread diffusely to produce alveolar damage and organizing pneumonia. The occurrence of this rapidly fatal ADV pneumonia mainly affecting the pediatric population, early in the posttransplantation course, suggests that the infection is primary to the recipient with ADV either originating and reactivating in the donor lung or acquired from the upper respiratory tract of the recipient. The characteristic smudgy intranuclear inclusions of ADV, as well as IHC and ISH positivity, were observed in the lungs of all autopsies. Antemortem biopsy demonstration of ADV by inclusion formation, IHC, and ISH was observed in two patients. In another patient, antemortem ADV was shown only by ISH, and the recognition of inclusions was made difficult by coexistent CMV infection. Although IHC and ISH may have the potential for detecting early infection, recognition of the characteristic clinical setting with necrotizing bronchocentric pneumonia and smudgy intranuclear inclusions should alert one to the diagnosis of ADV pneumonia.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/3. platelet-derived growth factor expression in primary pulmonary hypertension: comparison of HIV seropositive and HIV seronegative patients.Primary pulmonary hypertension (PPH) is characterized by intimal fibrosis and cell proliferation (including fibroblasts, smooth muscle and endothelial cells) in the distal pulmonary arterial tree. Considerable interest has been generated by recent reports of PPH in human immunodeficiency virus (HIV)-1-infected individuals. Although the lack of evidence for a pulmonary artery infection has suggested that in such cases HIV may act through mediator release rather than by direct endothelial infection, the mechanisms underlying HIV-associated PPH remain poorly defined. platelet-derived growth factor (PDGF) has the ability to induce smooth muscle cell and fibroblast proliferation and migration. Given these considerations, we have attempted to document a possible role for PDGF in PPH occurring in HIV seropositive and seronegative patients. Using semiquantitative polymerase chain reaction (PCR), PDGF A-chain messenger ribonucleic acid (mRNA) expression was analysed in surgical lung biopsies from 13 HIV seronegative patients and one HIV seropositive patient, all displaying severe PPH. In parallel, lung samples from two patients with hiv-1-associated PPH were studied by immunohistochemistry and in situ hybridization. Results were compared to those obtained in three hiv-1-infected individuals with no pulmonary complication (as demonstrated by clinical, radiological, bacteriological, and necropsy findings) and five control lung biopsies. As compared to controls, PDGF A-chain mRNA expression is elevated in lung biopsies from patients displaying PPH (p=0.029). In hiv-1-associated PPH, interstitial perivascular cells expressing PDGF A-chain mRNA and protein could be detected by in situ hybridization and immunohistochemistry, respectively. platelet-derived growth factor expression is elevated in lung biopsies of patients displaying primary pulmonary hypertension. Growth factors such as platelet-derived growth factor may play a part in the initiation and/or progression of primary pulmonary hypertension.- - - - - - - - - - ranking = 2keywords = hybridization (Clic here for more details about this article) |