Emphysematous lung destruction by cigarette smoke. The effects of latent adenoviral infection on the lung inflammatory response.

This study was designed to test the hypothesis that cigarette smoke-induced inflammation and emphysema are amplified by the presence of latent adenoviral (Ad) infection, and to determine whether this emphysematous process can be reversed by all-trans-retinoic acid (RA) treatment. The results confirm that in guinea pigs, chronic cigarette-smoke exposure caused lesions similar to human centrilobular emphysema. They also show that latent Ad infection combined with cigarette-smoke exposure caused an excess increase in lung volume (P < 0.001), air-space volume (P < 0.001), and lung weight (P < 0.01), and further decrease in surface-to-volume ratio (P < 0.001) compared with smoke exposure alone. RA treatment failed to reverse these emphysematous changes. Analysis of inflammatory response in parenchymal and airway tissue showed that smoking caused an increase of polymorphonuclear leukocytes (PMNs) (P < 0.0002), macrophages (P < 0.001), and CD4 cells (P < 0.0009), and that latent Ad infection independently increased PMNs (P < 0.001), macrophages (P = 0.003), and CD8 cells (P < 0.001). We conclude that latent Ad infection amplifies the emphysematous lung destruction and increases the inflammatory response produced by cigarette-smoke exposure. In this study, the increase in CD4 was associated with cigarette smoke and the increase in CD8 cells with latent Ad infection.     

B cell early response gene expression coupled to B cell receptor,CD40 and interleukin-4 receptor co-stimulation: evidence for a role of the egr-2/krox20 transcription factor in B cell proliferation

B lymphocytes are activated following antigen stimulation of the B cell receptor but require co-stimulation with accessory molecules provided by interleukin (IL)-4/CD40 ligand for cell cycle progression and proliferation. By analyzing a panel of 11 early response genes induced by cross-linking of surface immunoglobulin, we show that CD40 signaling alone induces only 2 genes, c-myc together with an anonymous gene, 3L3, and that these are distinct from the set of genes induced in response to IL-4. Co-stimulation with the proliferative combination of anti-μ, IL-4 + CD40 signaling led to a fourfold enhancement of egr-2/krox20 expression over that seen with anti-μ alone. Egr-2 expression/activity was selectively inhibited by the immunosuppressive drug cyclosporin A, and antisense oligonucleotide blockade of Egr-2 activity elicited a dose-dependent inhibition of B cell proliferation. Taken together, these observations show that the early gene regulatory programs coupled to different surface receptors on B cells are largely distinct from each other, but that certain genes, exemplified by egr-2, may represent a point of convergence in the integration of different signaling pathways into the B cell proliferative response.     

Use of multiepitope polyproteins in serodiagnosis of active tuberculosis

Screening of genomic expression libraries from Mycobacterium tuberculosis with sera from tuberculosis (TB) patients or rabbit antiserum to M. tuberculosis led to the identification of novel antigens capable of detecting specific antibodies to M. tuberculosis. Three antigens, Mtb11 (also known as CFP-10), Mtb8, and Mtb48, were tested together with the previously reported 38-kDa protein, in an enzyme-linked immunosorbent assay (ELISA) to detect antibodies in TB patients. These four proteins were also produced as a genetically fused polyprotein, which was tested with two additional antigens, DPEP (also known as MPT32) and Mtb81. Sera from individuals with pulmonary and extrapulmonary TB, human immunodeficiency virus (HIV)-TB coinfections, and purified protein derivative (PPD)-positive and PPD-negative status with no evidence of disease were tested. In samples from HIV-negative individuals, the ELISA detected antibodies in >80% of smear-positive individuals and >60% smear-negative individuals, with a specificity of approximately 98%. For this group, smears detected 81.6% but a combination of smear and ELISA had a sensitivity of approximately 93%. The antigen combination detected a significant number of HIV-TB coinfections as well as antibodies in patients with extrapulmonary infections. Improved reactivity in the HIV-TB group was observed by including the antigen Mtb81 that was identified by proteomics. The data indicate that the use of multiple antigens, some of which are in a single polyprotein, can be used to facilitate the development of a highly sensitive test for M. tuberculosis antibody detection.     

Postural muscle responses to multidirectional translations in patients with Parkinson's disease

The postural adaptation impairments of patients with Parkinson's disease (PD) suggest that the basal ganglia may be important for quickly modifying muscle activation patterns when the direction of perturbation or stance conditions suddenly change. It is unknown whether their particular instability to backward postural perturbations is due to specific abnormalities of parkinsonian postural muscle synergies in that direction and not present in other directions. In the present study, we test this hypothesis by comparing the patterns of leg and trunk muscle activation in 13 subjects with PD and 13 control subjects in response to eight randomly presented directions of horizontal surface translations while standing with either narrow or wide stance. The direction of maximum activation for each muscle was similar for PD and control subjects, suggesting that the basal ganglia is not critical for programming externally triggered postural synergies. However, antagonist muscle activation was earlier and larger in PD than in control subjects, resulting in coactivation. PD subjects also did not increase the magnitude of muscle activation as much as did control subjects when changing from wide to narrow stance. These results are consistent with the hypothesis that PD results in an inability to shape the pattern and magnitude of postural muscle responses for changes in perturbation direction and in stance position.     

The modification by ketotifen of respiratory responses to histamine and antigen in guinea-pigs

Aerosolized solutions of histamine or ovalbumin were administered to control or ovalbumin-sensitized guinea-pigs. The time to onset of respiratory distress (preconvulsion time) during challenge with these agents was measured using a force-displacement transducer on the animal's back. The preconvulsion time for each guinea-pig was compared with and without ketotifen pretreatment. Ketotifen administered both by aerosol and intraperitoneal injection (i.p.) significantly protected (p<0.001) each guinea-pig from the effects of aerosol challenge with histamine. Ovalbumin-sensitized animals were also protected from the effects of antigen aerosol challenge by ketotifen pretreatment. Sodium cromoglycate (DSCG), administered as an aerosol, did not protect sensitized animals from ovalbumin challenge. The Konzett-Rössler technique was used to measure the response to the intravenous injection (i.v.) of histamine in anaesthetized artificially ventilated guinea-pigs. Ketotifen was three times more potent than mepyramine in inhibiting the histamine-induced increase in air overflow volume.     

Ultrastructural Changes Suggestive of Focal Segmental Glomerulosclerosis in Atypical Minimal Change Nephrotic Syndrome

In an attempt to recognize early stages of focal segmental glomerulosclerosis (FSGS) in patients with a clinical course suggesting a diagnosis other than minimal change disease (MCD) and normal histology, or minor, nondiagnostic changes on light microscopy (LM), we used a protocol for systematic and extensive electron microscopy (EM) examination of kidney biopsies obtained from such patients. By this method ultrastructural pathology was found in 8 patients. These changes were localized, involving only portions of single glomerular segments. The findings included mild to moderate increase of the mesangial matrix, focal wrinkling of the capillary basement membrane, and early obliteration of the normal architecture of individual capillary loops, as well as electron-dense deposits in a mesangial and subendothelial distribution. Of these 8 patients, 2 are at present in remission without therapy (in 1, following therapy with cyclophosphamide); 3 are in remission on steroid therapy; 1 developed massive proteinuria during pregnancy, after a spontaneous remission lasting almost 2 years; 1 patient advanced to terminal renal failure 3 1/2 years after biopsy; and 1 died of sepsis 1 month after biopsy. We believe that the ultrastructural changes found may represent early or mild FSGS and that the protocol described can add valuable information in clinically worrisome patients in whom renal histology appears normal.     

„Klar bleiben“ – ein Wettbewerb für Schulklassen zur Reduktion des Alkoholkonsums

Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Alkohol ist in Deutschland im Jugendalter die populärste Droge. Alkoholpräventionsprogramme, die im Setting Schule...