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M Tamm

Publications and source records attributed to M Tamm.

At least 55 records · Page 3Linked to original sources
PubMed2001

Pulmonary mucosa-associated lymphoid tissue lymphoma in a patient with common variable immunodeficiency syndrome.

Common variable immunodeficiency syndrome (CVID) is a primary immunodeficiency typically presenting with recurrent sinopulmonary infections. Non-Hodgkin's lymphoma and other secondary cancers are typical late complications of CVID. We report on a patient suffering from CVID with a history of recurrent sinopulmonary infections, interstitial pulmonary changes and hepatic granulomas. Despite treatment with intravenous immunoglobulin followed by a reduction in the number of pulmonary infections, reticular and nodular lung changes progressed. Video-assisted thoracoscopic lung biopsy showed a low-grade B cell lymphoma of the mucosa-associated lymphoid tissue (MALT) of the bronchus without evidence of pulmonary infection. In conclusion, MALT lymphoma of the lung should be considered in the differential diagnosis of progressive lung disease in CVID.

Adult↗
PubMed2001

Increased frequency of Chlamydia pneumoniae antibodies in patients with asthma.

The worldwide increase in asthma incidences and the impact of the disease on public health care have led to new investigations of the cause of the disease. Besides well-defined environmental causes, accumulating evidence suggests that respiratory tract infections play an important role in the pathogenesis of asthma. Among these microorganisms Chlamydia pneumoniae is an intracellular pathogen causing persistent infection. Chlamydia pneumoniae infection has been discussed as possibly inducing the development of asthma. This study was designed to investigate the presence of C. pneumoniae-specific IgG, IgA, and IgM antibodies in serum samples of 33 adults with a clinical history of asthma, positive methacholine test, and reduced FEV(1). Patients with asthma were compared with age-, sex-, and locality-matched control subjects (n = 33). We observed no acute infection either in patients with asthma or in control subjects, but 63% of all investigated individuals had signs of past infection. Chlamydia pneumoniae-specific IgA was detected in 52% of the patients with asthma and in 15% of the healthy control subjects (p < 0.01). Serological evidence of chronic infection with C. pneumoniae (high IgG [> pr = 1:512] and high IgA [> or = 1:40]) was more frequent in patients with asthma (18.2%) compared with control subjects (3.0%) (p < 0.01). Our results provide further evidence that chronic infection with C. pneumoniae is linked to asthma.

Adult↗
PubMed2001

Pulmonary cytomegalovirus infection in immunocompromised patients.

BACKGROUND: Cytomegalovirus (CMV) infection and CMV disease are frequent complications in immunocompromised patients. In this study, the incidence of pulmonary CMV infection was analyzed in different groups of immunocompromised patients and the diagnostic value of immunostaining with anti-CMV antibodies in BAL cells was evaluated in regard to the diagnosis of CMV pneumonitis. METHODS: Five hundred eighty consecutive BAL procedures were analyzed prospectively in 442 immunocompromised and 126 nonimmunocompromised control subjects. CMV culture in BAL fluid was performed by shell vial assay and immunostaining using three monoclonal anti-CMV antibodies. RESULTS: The incidence of culture results positive for CMV in the BAL fluid varied from 20 to 30% in HIV-positive patients, in patients following stem cell or renal transplantation, and in patients with autoimmune disease or lung fibrosis treated with immunosuppressive agents. CMV was cultured from 4.4% of BALs in patients treated with high-dose chemotherapy and from 2.4% of control subjects. CMV disease developed in 37 patients; in 18 of these patients, CMV pneumonitis was present. The results of CMV immunostaining were positive in a total of 22 BALs, all in patients with CMV disease. The sensitivity, specificity, and positive and negative predictive values of positive CMV immunostaining results for the diagnosis of CMV pneumonitis were 88.9%, 98.6%, 72.7%, and 99.5%, respectively. CONCLUSION: The incidence of pulmonary CMV infection is similar in different groups of immunocompromised patients except for patients following high-dose chemotherapy. CMV immunostaining in the BAL fluid is a very helpful method to diagnose CMV pneumonitis in these patients.

Antibodies, Viral↗
PubMed2001

Interventional bronchoscopy for the management of airway complications following lung transplantation.

STUDY OBJECTIVES: To assess the efficacy and complications of different interventional bronchoscopic techniques used to treat airway complications after lung transplantation. DESIGN: Retrospective study. SETTING: Heart-lung transplant unit of a university hospital. PATIENTS: From November 1986 to January 2000, interventional bronchoscopy was performed in 41 of 312 lung transplant recipients (13.1%) for tracheobronchial stenosis, bronchomalacia, granuloma formation, and dehiscence. INTERVENTIONS: Dilatation, stent placement, laser or forceps excision. MEASUREMENTS AND RESULTS: Mean (+/- SE) improvement in FEV(1) in 26 patients undergoing dilatation for a stenotic or a combined lesion was 93 +/- 334 mL or 8 +/- 21%. In seven of these patients not proceeding to stent placement, mean improvement in FEV(1) was 361 +/- 179 mL or 21 +/- 9%. Patients needing stent placement after dilatation had a mean change in FEV(1) after dilatation of - 5 +/- 325 mL or 3 +/- 23%, and an improvement of 625 +/- 480 mL or 52 +/- 43% after stent insertion. Mean improvement in FEV(1) for patients treated with stent insertion for bronchomalacia was 673 +/- 30 mL or 81 +/- 24%. Complications of airway stents were migration (27%), mucous plugging (27%), granuloma formation (36%), stent fracture (3%), and formation of a false passage (6%). Mortality associated with interventional bronchoscopy was 2.4% (1 of 41 patients). For patients with airway complications successfully undergoing interventional bronchoscopy, the overall 1-year, 3-year, and 5-year survival rates were 79%, 45%, and 32%, respectively, vs 87%, 69%, and 56% for those without airway complications (p < 0.05). CONCLUSION: Only a small number of patients with airway stenosis after lung transplantation will respond to bronchial dilatation alone. Patients with airway complications after lung transplantation have a higher mortality than patients without airway complications.

Adolescent↗
PubMed2000

[Cystic fibrosis].

Explore the source record for details and available documents.

Cystic Fibrosis↗
PubMed2000

[Early detection of exacerbation of lung infections in patients with cystic fibrosis by means of daily spirometry].

UNLABELLED: The clinical course of cystic fibrosis is characterised by pulmonary involvement with mucus retention, chronic pulmonary infection and parenchymal inflammation. Recurrent infectious exacerbations are usually accompanied by a fall in lung volumes. This pilot study investigated whether exacerbations can be detected early by daily spirometry. Ten patients with cystic fibrosis (5 female; 5 male; mean age 24.9 years) performed daily spirometry using a portable transtelephonic spirometer (Spirophone). Infectious exacerbations were diagnosed on clinical grounds and treated without knowledge of the spirometry results. Data of 9 patients recorded over a period of 5-11 months were analysed. One patient was excluded due to non-compliance. A total of 20 infectious exacerbations occurred during the observation period. A fall of at least 20% in one or more of the following parameters was observed in 90% (18/20) of exacerbations: FVC, FEV1, PEF, and FEF25/75. A daily drop in lung volumes of 0.7% to 1.2% was recorded beginning at a median of 33 (20 to 120) days before infectious exacerbations were diagnosed. There was a 2-3% daily improvement in spirometric data under treatment with antibiotics. CONCLUSION: Daily spirometry allows early recognition of pulmonary infectious exacerbations in patients with cystic fibrosis. Daily spirometry may be used as an indicator for early antibiotic treatment.

Adolescent↗
PubMed2000

[Inhaled colistin in cystic fibrosis].

UNLABELLED: The clinical course of cystic fibrosis (CF) is characterised by chronic bronchial infection with Pseudomonas aeruginosa. Therapy with inhaled aminoglycosides was introduced to decrease the rate of infectious exacerbations and to delay pulmonary progression. However, development of resistance to aminoglycosides is frequent. Few investigations are available into the resistance profile under treatment with colistin. Antibiotic resistance to colistin was analysed in 44 adult CF patients treated with inhaled colistin. Resistance to aminoglycosides was observed in 86% of cases (38/44) before therapy and decreased to 43% (19/44) under treatment with colistin. Five patients (11%) developed polymyxin resistance. After cessation of therapy pseudomonas became sensitive to polymyxin within a few months and enabled colistin to be reintroduced. In addition, we performed a pilot study analysing the effect of inhaled colistin on the growth of pseudomonas. The number of Pseudomonas aeruginosa decreased from 16.7 million (CFU) bacteria per ml sputum to 2.9 million under therapy with colistin. There was a more than tenfold increase in bacterial counts after inhaled colistin was stopped. Genotyping revealed no change in the type of pseudomonas strains. CONCLUSION: Development of resistance to polymyxin is not rare under long-term treatment with inhaled colistin and requires temporary interruption of therapy. Sputum cultures should therefore be tested regularly for polymyxin resistance in patients treated with inhaled colistin.

Administration, Inhalation↗
PubMed2000

Towards an artificial model for Photosystem II: a manganese(II,II) dimer covalently linked to ruthenium(II) tris-bipyridine via a tyrosine derivative.

In order to model the individual electron transfer steps from the manganese cluster to the photooxidized sensitizer P680+ in Photosystem II (PS II) in green plants, the supramolecular complex 4 has been synthesized. In this complex, a ruthenium(II) tris-bipyridine type photosensitizer has been linked to a manganese(II) dimer via a substituted L-tyrosine, which bridges the manganese ions. The trinuclear complex 4 was characterized by electron paramagnetic resonance (EPR) and electrospray ionization mass spectrometry (ESI-MS). The excited state lifetime of the ruthenium tris-bipyridine moiety in 4 was found to be about 110 ns in acetonitrile. Using flash photolysis in the presence of an electron acceptor (methylviologen), it was demonstrated that in the supramolecular complex 4 an electron was transferred from the excited state of the ruthenium tris-bipyridine moiety to methylviologen, forming a methylviologen radical and a ruthenium(III) tris-bipyridine moiety. Next, the Ru(III) species retrieved the electron from the manganese(II/II) dimer in an intramolecular electron transfer reaction with a rate constant kET > 1.0 x 10(7) s(-1), generating a manganese(II/III) oxidation state and regenerating the ruthenium(II) photosensitizer. This is the first example of intramolecular electron transfer in a supramolecular complex, in which a manganese dimer is covalently linked to a photosensitizer via a tyrosine unit, in a process which mimics the electron transfer on the donor side of PS II.

2,2'-Dipyridyl↗
PubMed2000

Hypoxia modifies the effect of PDGF on glycosaminoglycan synthesis by primary human lung cells.

Hypoxia, a consequence of interstitial lung diseases, may lead to secondary pulmonary hypertension and pulmonary vascular remodeling. Hypoxia induces activation and proliferation of lung cells and enhances the deposition of extracellular matrix including glycosaminoglycans (GAGs). To elucidate the cell biological mechanisms underlying the development of secondary pulmonary hypertension, we studied the effect of hypoxia on GAG synthesis by human lung cells. GAG synthesis was measured by incorporation of [(3)H]glucosamine; GAGs were isolated, purified, and characterized with GAG-degrading enzymes. Fibroblasts and vascular smooth muscle cells (VSMCs) synthesized hyaluronic acid, heparan sulfate, and chondroitin sulfates, whereas dermatan sulfate was found only in fibroblasts. Hypoxia did not influence the size or charge of the individual GAGs. However, hypoxia inhibited platelet-derived growth factor-induced [(3)H]glucosamine incorporation in secreted GAGs, especially hyaluronic acid, in VSMCs. In contrast, it stimulated GAG secretion, specifically heparan sulfate, by fibroblasts. Our results indicate that hypoxia induces modifications in GAG synthesis by human lung VSMCs and fibroblasts that may be correlated to pathophysiological manifestations in lung diseases causing hypoxia.

Cell Hypoxia↗
PubMed2000

Prospective randomized comparison of thoracoscopic talc poudrage under local anesthesia versus bleomycin instillation for pleurodesis in malignant pleural effusions.

Induction of pleurodesis offers benefit for patients with metastatic tumors and symptomatic malignant pleural effusions, but the best method for achieving this is still unknown. In this prospective, randomized comparison of two well-established pleurodesis procedures, 36 patients with malignant pleural effusions, expanded lungs after drainage, and expected survival of > 1 mo received either bleomycin instillation (60E) via a small-bore thoracostomy tube or thoracoscopic talc poudrage (5 g) under local anesthesia. Efficacy, safety, and cost could be evaluated for 32 treatments (17 bleomycin, 15 talc) in 31 patients. Recurrence rates of effusion with bleomycin and talc poudrage after 30 d were 41% and 13% (p = 0.12), respectively, those after 90 d were 59% and 13%, respectively (p = 0.01), and those after 180 d were 65% and 13% (p = 0.005), respectively. Neither procedure showed any major adverse effect, and both were equally well tolerated. Cost estimation favored thoracoscopic talc poudrage, both for the initial hospitalization and with regard to recurrences. In conclusion, thoracoscopic talc pleurodesis under local anesthesia is superior to bleomycin instillation for pleurodesis in cases of malignant pleural effusion.

Aged↗
PubMed2000

Granulomatous Pneumocystis carinii pneumonia in Wegener's granulomatosis.

This study reports on a first case of granulomatous Pneumocystis carinii pneumonia (PCP) in a human immunodeficiency virus-negative patient with antineutrophil cytoplasmic antibody-positive Wegener's granulomatosis whilst receiving immunosuppressive treatment. The patient presented with diffuse alveolar haemorrhage, pauci-immune rapid progressive glomerulonephritis and leukocytoclastic vasculitis of the skin. Granulomatous Pneumocystis carinii pneumonia developed under immunosuppressive treatment with cyclophosphamide and prednisone. At the time Pneumocystis carinii pneumonia developed, there was a marked lymphopenia with a very low CD8+ cell count in the blood. Grocott staining in bronchoalveolar lavage fluid revealed no Pneumocystis carinii. The diagnosis was made via a video-assisted thoracoscopic lung biopsy which showed granulomas containing high numbers of Pneumocystis carinii cysts.

Biopsy↗