[Comparison of patient therapy adherence of two structural different memory clinics]. / Vergleich der Therapietreue von zwei regional benachbarten Gedächtnissprechstunden mit unterschiedlicher Struktur.

There are more than 100 memory clinics established in Germany, Austria and German-speaking Switzerland. We compared the impact of the structure of two German memory clinics (Erlangen and Nuremberg) on therapeutic outcome. 483 patients suffering from dementia with indication for antidementive therapy were included in this study. The data ascertainment included patient-related data, the mini mental score, comorbidity as well as psychiatric drug therapy. After a mean follow-up of 3.7 years, we performed a single cross-sectional survey covering over 90 % of patients to assess clinical course and adherence to therapy. The patients of the Erlangen University Memory Clinic were significantly younger (69.8 +/- 9.49 vs. 74.6 +/- 10.7 years; p = 0.01) and had a better mini mental score at their first presentation (20.9 +/- 9.4 vs. 19.5 +/- 5.9; p = 0.02). They showed a non-significantly faster disease progression (as measured by mini mental decline per year), than the patients from Nuremberg. Concerning the allocation of diagnosis, more late onset-dementias and dementias of a mixed type were treated at the Nuremberg clinic. At the university clinic, more dementias were of unclassified origin. Concomitant drug therapies, death rates and therapy adherence (53 %) were not different between the two clinics. The two memory clinics under investigation differed in patient age, disease severity and diagnostic assessment. Still, parameters of therapeutic outcome showed converging results.

Pharmacological inhibition of c-Abl compromises genetic stability and DNA repair in Bcr-Abl-negative cells.

Imatinib inhibits the kinase activity of Bcr-Abl and is currently the most effective drug for treatment of chronic myeloid leukemia (CML). Imatinib also blocks c-Abl, a physiological tyrosine kinase activated by a variety of stress signals including damaged DNA. We investigated the effect of pharmacological inhibition of c-Abl on the processing of irradiation-induced DNA damage in Bcr-Abl-negative cells. Cell lines and peripheral blood mononuclear cells (PBMCs) from healthy volunteers were treated with imatinib or dasatinib before gamma-irradiation. Inhibition of c-Abl caused an enhanced irradiation-induced mutation frequency and slowdown of DNA repair, whereas imatinib was ineffective in cells expressing a T315I variant of c-Abl. Mutation frequency and repair kinetics were also studied in c-Abl-/- murine embryonic fibroblasts (MEFs) retransfected with wild-type c-Abl (wt-Abl) or a kinase-defect variant of Abl (KD-Abl). Enhanced mutation frequency as well as delayed DNA repair was observed in cells expressing KD-Abl. These data indicate that pharmacological inhibition of c-Abl compromises DNA-damage response.

Tumor necrosis factor (TNF)-alpha-induced interleukin-8 in human blood cultures discriminates neutralization by the p55 and p75 TNF soluble receptors.

The dose-dependent increase in mortality in patients with sepsis who are treated with tumor necrosis factor (TNF) p75 soluble receptor Fc conjugate (p75-Fc) remains unexplained. In this study, neutralization of TNF-alpha-induced interleukin (IL)-8 by p75-Fc in whole human blood exhibited a U-shaped inhibition curve, whereas the TNF-soluble p55 receptor, linked to polyethylene glycol (p55-PEG), exhibited a dose-dependent inhibition. Native soluble p75 increased TNF-alpha-induced IL-8, versus a 61% reduction by native p55. Spontaneous IL-8 production was increased by p75-Fc or native p75 but not by p55-PEG or native p55. Unexpectedly, TNF-alpha-stimulated IL-1 receptor antagonist was suppressed by p75-Fc but not by p55-PEG. Studies of binding to TNF trimer revealed that p75-Fc has an affinity 40-fold lower than that of p55-PEG and a faster off rate. Native and p75-Fc pass TNF-alpha to membrane receptors more readily than does native or p55-PEG, which may partly explain the increased mortality in patients with sepsis who are treated with p75-Fc.

Characterization of a new human B7-related protein: B7RP-1 is the ligand to the co-stimulatory protein ICOS.

Optimal T cell activation requires the interactions of co-stimulatory molecules, such as those in the CD28 and B7 protein families. Recently, we described the co-stimulatory properties of the murine ligand to ICOS, which we designated as B7RP-1. Here, we report the co-stimulation of human T cells through the human B7RP-1 and ICOS interaction. This ligand-receptor pair interacts with a K:(D) approximately 33 nM and an off-rate with a t((1/2)) > 10 min. Interestingly, tumor necrosis factor (TNF)-alpha differentially regulates the expression of human B7RP-1 on B cells, monocytes and dendritic cells (DC). TNF-alpha enhances B7RP-1 expression on B cells and monocytes, while it inhibits it on DC. The human B7RP-1-Fc protein or cells that express membrane-bound B7RP-1 co-stimulate T cell proliferation in vitro. Specific cytokines, such as IFN-gamma and IL-10, are induced by B7RP-1 co-stimulation. Although IL-2 levels are not significantly increased, B7RP-1 co-stimulation is dependent on IL-2. These experiments define the human ortholog to murine B7RP-1 and characterize its interaction with human ICOS.

Delineation of human antibody responses to culture filtrate antigens of Mycobacterium tuberculosis.

This study was undertaken to define the antigens in culture filtrates of actively replicating Mycobacterium tuberculosis that are recognized by antibodies from tuberculosis (TB) patients. Two-dimensional Western blots were probed with sera from healthy controls and TB patients that were preabsorbed with Escherichia coli lysates to deplete cross-reactive antibodies. Antibodies from TB patients recognized 26 of the >100 culture filtrate proteins, and the repertoire changed with disease progression. Only 12 of 26 antigens, including 3 proteins implicated in colonization and invasion by mycobacteria (MPT51, MPT32, and 85C), and 9 (as yet undefined proteins) were reactive with sera from TB patients with early noncavitary or cavitary disease. Eight additional antigens, including 4 undefined proteins, were recognized only by sera from a subset of patients with advanced cavitary disease. Studies suggest that 3 of the antigens recognized by sera from patients with early TB (85C, MPT32, and a 88-kDa protein) have strong serodiagnostic potential.

Definition of Mycobacterium tuberculosis culture filtrate proteins by two-dimensional polyacrylamide gel electrophoresis, N-terminal amino acid sequencing, and electrospray mass spectrometry.

A number of the culture filtrate proteins secreted by Mycobacterium tuberculosis are known to contribute to the immunology of tuberculosis and to possess enzymatic activities associated with pathogenicity. However, a complete analysis of the protein composition of this fraction has been lacking. By using two-dimensional polyacrylamide gel electrophoresis, detailed maps of the culture filtrate proteins of M. tuberculosis H37Rv were generated. In total, 205 protein spots were observed. The coupling of this electrophoretic technique with Western blot analysis allowed the identification and mapping of 32 proteins. Further molecular characterization of abundant proteins within this fraction was achieved by N-terminal amino acid sequencing and liquid chromatography-mass spectrometry. Eighteen proteins were subjected to N-group analysis; of these, only 10 could be sequenced by Edman degradation. Among the most interesting were a novel 52-kDa protein demonstrating significant homology to an alpha-hydroxysteroid dehydrogenase of Eubacterium sp. strain VPI 12708, a 25-kDa protein corresponding to open reading frame 28 of the M. tuberculosis cosmid MTCY1A11, and a 31-kDa protein exhibiting an amino acid sequence identical to that of antigen 85A and 85B. This latter product migrated with an isoelectric point between those of antigen 85A and 85C but did not react with the antibody specific for this complex, suggesting that there is a fourth member of the antigen 85 complex. Novel N-terminal amino acid sequences were obtained for three additional culture filtrate proteins; however, these did not yield significant homology to known protein sequences. A protein cluster of 85 to 88 kDa, recognized by the monoclonal antibodies IT-57 and IT-42 and known to react with sera from a large proportion of tuberculosis patients, was refractory to N-group analysis. Nevertheless, mass spectrometry of peptides obtained from one member of this complex identified it as the M. tuberculosis KatG catalase/peroxidase. Thus, the detailed mapping of M. tuberculosis proteins, combined with state-of-the-art analytical techniques such as mass spectrometry, provides a basis for further analysis and rapid identification of biologically relevant molecules.

Surrogate marker of preclinical tuberculosis in human immunodeficiency virus infection: antibodies to an 88-kDa secreted antigen of Mycobacterium tuberculosis.

Antibodies to purified, size-fractionated secreted proteins of Mycobacterium tuberculosis in sera from patients with human immunodeficiency virus (HIV) infection and active tuberculosis (HIV/TB patients), and in stored sera obtained from the same patients prior to clinical manifestation of TB, were evaluated by ELISA, and the repertoire of antigens recognized was analyzed by immunoblotting. Compared with non-HIV/TB patients, HIV/TB patients had lower levels of anti-mycobacterial antibodies, and these were directed toward a restricted set of antigens. Antibodies to an 88-kDa secreted antigen were present in the sera of 74% of HIV/TB patients during the years (1.5-6) prior to manifestation of active, clinical tuberculosis, although only 66% were positive by the time tuberculosis was diagnosed. The presence of antibodies to the 88-kDa antigen can serve as a surrogate marker for identifying HIV-infected persons with active, subclinical disease who are at a high risk of developing clinical tuberculosis.

Human humoral responses to antigens of Mycobacterium tuberculosis: immunodominance of high-molecular-mass antigens.

The selection of antigens of Mycobacterium tuberculosis for most studies of humoral responses in tuberculosis patients has been restricted to molecules that were either immunodominant in immunized animals or amenable to biochemical purification rather than those that were reactive with the human immune system. Delineation of antigens that elicit humoral responses during the natural course of disease progression in humans has been hindered by the presence of cross-reactive antibodies to conserved regions on ubiquitous prokaryotic antigens in sera from healthy individuals and tuberculosis patients. The levels of cross-reactive antibodies in the sera were reduced by preadsorption with Escherichia coli lysates, prior to studying their reactivity against a large panel of M. tuberculosis antigens to which the human immune system may be exposed during natural infection and disease. Thus, reactivity against pools of secreted, cellular, and cell wall-associated antigens of M. tuberculosis was assessed by an enzyme-linked immunosorbent assay (ELISA). Initial results suggested that the secreted protein preparation contained antigens most frequently recognized by the humoral responses of pulmonary tuberculosis patients. The culture filtrate proteins were subsequently size fractionated by preparative polyacrylamide gel electrophoresis, characterized by reaction with murine monoclonal antibodies to known antigens of M. tuberculosis by an ELISA, and assessed for reactivity with tuberculous and nontuberculous sera. Results show that a secreted antigen of 88 kDa elicits a strong antibody response in a high percentage of patients with pulmonary tuberculosis. This and other antigens identified on the basis of their reactivity with patient sera may prove useful for developing serodiagnosis for tuberculosis.

Characteristics of protective immunity engendered by vaccination of mice with purified culture filtrate protein antigens of Mycobacterium tuberculosis.

In this study highly purified culture filtrate proteins obtained from Mycobacterium tuberculosis strains Erdman and H37Rv were tested for their capacity to stimulate immune T cells in vitro, and to immunize mice in vivo. Analysis of the culture filtrate antigen pool revealed a complex mixture of proteins; after separation of this pool into fractions of defined molecular size using an electrophoretic method, it was found that multiple fractions strongly stimulated interferon-gamma (IFN-gamma) secretion by immune CD4 T cells in vitro. In a further series of experiments mice were given multiple immunizations with the culture filtrate protein pool suspended in emulsions of incomplete Freund's adjuvant. Such mice were as resistant as mice given live bacillus Calmette-Guérin (BCG) vaccine to a low dose aerosol challenge infection with M. tuberculosis, but this resistance waned to low levels by 5 months post-vaccination. Furthermore, experiments using the filtrate antigens to boost or augment immunity induced by the BCG vaccination itself were unsuccessful. These data therefore support the hypothesis that the culture filtrate proteins of M. tuberculosis contain multiple antigens that are strongly recognized by T cells acquired during the initial expression of protective immunity to tuberculosis. Conventional immunization with these purified protein antigens can engender a strong degree of protective immunity, but this immunity is apparently not sustained at the same level as that induced by the live vaccine, perhaps suggesting a lack of suitable stimulation of memory immunity.

Drug-resistant strains of Mycobacterium tuberculosis exhibit a range of virulence for mice.

A panel of clinical isolates of Mycobacterium tuberculosis, several of which were resistant to one or more antimycobacterial drugs, were tested for their capacity to give rise to active disease following aerogenic infection of normal immunocompetent mice. The panel exhibited a range of virulence in this model, which followed no clear trend in terms of geographical source, degree of drug resistance, or rate of growth in vitro. Several isolates grew very quickly over the first 20 days in mouse lungs before being contained by emerging immunity. In view of this latter observation, we hypothesize that it is possible that such so-called fast growers may be responsible for the rapid fatality sometimes seen in immunocompromised patients with tuberculosis. Moreover, the results of the study do not support the belief that increased drug resistance usually associates with loss of virulence of the isolate.

Isolation of salmonellae from dried rattlesnake preparations.

Salmonella arizonae and other Salmonella serovars were isolated from four different rattlesnake preparations which were used for self-treatment of various diseases. A case of disseminated S. arizonae infection is reported in a patient who had acquired immunodeficiency syndrome and ingested dried rattlesnake.

Five years' experience of bacteraemia in sickle-cell anaemia.

In a review of all adults admitted with sickle-cell anaemia to Cook County Hospital between January 1980 and April 1985, 15 instances of bacteraemia were identified. In these patients, bacteraemia was characterised by slow onset, an identifiable focus of infection and lack of hypotension or abnormal coagulation of the blood. The organisms, most often isolated were Escherichia coli and Salmonella species. Two patients died, both with Salmonella enteritidis bacteraemia. Neither death could be attributed to the acute effects of infection. The outcome of bacteraemia in adults with sickle-cell anaemia appears to be more favourable than that in children.