PubMed Health⌕ Search

Biomedical subjects

Wolfgang Wagner

Publications and source records attributed to Wolfgang Wagner.

At least 19 recordsLinked to original sources

Long-term course of epilepsy in a large cohort of intellectually disabled patients.

UNLABELLED: This study was designed to describe the course of epilepsy (in terms of seizure frequency) and to assess the variables (antiepileptic therapy regimens and others) correlated to improvement. Seizure frequency (categories: seizure free, more than one seizure/year, monthly seizures, weekly seizures and daily seizures) and antiepileptic medication were retrospectively compared between 1992 and 2002 in a large cohort of 550 inpatients with chronic epilepsy and different degrees of intellectual disability or multiple handicaps. RESULTS: Seizure frequency decreased significantly (p<0.001). 218 of the 394 patients (55.3%) not seizure free in 1992 improved (changed into a better frequency category). The improvement rate was marginally higher in patients who had undergone a medication change (p=0.08). A high seizure frequency in 1992 (p=0.016) and older age (p=0.006), but not epilepsy syndrome or degree of intellectual disability, were predictors for improvement (stepwise logistic regression analysis). 56.4% of the improved patients were on combinations of two AEDs (17.4%, monotherapy; 20.2%, triple therapy). The most frequent therapy regimens in the improved patients were lamotrigine/valproate (48 patients), carbamazepine/phenobarbital (21) and carbamazepine only (19). Lamotrigine/valproate was effective in all kinds of epileptic syndromes. Most patients on lamotrigine had serum concentrations above 10microg/ml, approximately one half had dosages above 200mg/day. The rate of seizure freedom increased from 28.4 to 37.6%. The 84% of the patients seizure free in 1992 remained seizure free. Predictors for seizure freedom in 2002 were higher age (stepwise logistic regression, p<0.0005) and seizure freedom in 1992 (p<0.0005). CONCLUSIONS: Substantial improvement can be achieved even in intellectually disabled patients with chronic epilepsy. Although the rate of seizure freedom is reduced in comparison with a non-ID population, once seizure freedom has been achieved it is most likely to continue. For a majority of this patient population, monotherapy may not be sufficient. Lamotrigine/valproate appears to be a major therapeutic innovation.

Adolescent↗

The binding of DYNLL2 to myosin Va requires alternatively spliced exon B and stabilizes a portion of the myosin's coiled-coil domain.

The myosin Va light chain DYNLL2 has been proposed to function as an adaptor to link the myosin to certain cargo. Here, we mapped the binding site for DYNLL2 within the myosin Va heavy chain. Copurification and pull-down experiments showed that the heavy chain contains a single DYNLL2 binding site and that this site resides within a discontinuity in the myosin's central coiled-coil domain. Importantly, exon B, an alternatively spliced, three-amino acid exon, is a part of this binding site, and we show in the context of full-length myosin Va that this exon is required for DYNLL2-myosin Va interaction. We investigated the effect of DYNLL2 binding on the structure of a myosin Va heavy chain fragment that contains the DYNLL2 binding site and flanking sequence, only parts of which are strongly predicted to form a coiled coil. Circular dichroism measurements revealed a DYNLL2-induced change in the secondary structure of this dimeric myosin fragment that is consistent with an increase in alpha-helical coiled-coil content. Moreover, the binding of DYNLL2 considerably stabilizes this heavy chain fragment against thermal denaturation. Analytical ultracentrifugation yielded an apparent association constant of approximately 3 x 10(6) M(-1) for the interaction of DYNLL2 with the dimeric myosin fragment. Together, these data show that alternative splicing of the myosin Va heavy chain controls DYNLL2-myosin Va interaction and that DYNLL2 binding alters the structure of a portion of the myosin's coiled-coil domain. These results suggest that exon B could have a significant impact on the conformation and regulatory folding of native myosin Va, as well as on its interaction with certain cargos.

Alternative Splicing↗

Success and failure of endoscopic third ventriculostomy in young infants: are there different age distributions?

OBJECTIVE: Patient's age and etiology of hydrocephalus are the most important factors influencing the success rate of endoscopic third ventriculostomy (ETV). Failure rates are reported to be particularly high in the first year of age. On the basis of our own data and a metaanalysis of the literature, we try to further define the impact of age on ETV success in infants younger than 1 year. MATERIALS AND METHODS: Only patients with a minimum follow-up of 12 months were considered. Between October 1994 and July 2004, 28 patients younger than 1 year underwent ETV in our institution. Age ranged from 8 to 311 days (median 96). The etiology of hydrocephalus was aqueductal stenosis (AS) in all patients (idiopathic in 13, posthemorrhagic in three, postmeningitic in four, and related to CNS or vascular malformation or to tumor in eight). ETV failure was defined as subsequent need for shunt implantation. The metaanalysis of the literature took into account reported series on ETV in infants with detailed data on age and etiology in every single patient. RESULTS: In our own patients, ETV was successful in 13 patients and eventually failed in 15. In the ETV success group, the median age was 200 days and the mean age was 176 days (range 13-311 days). In the ETV failure group, the ages were 105 days (median), 117 days (mean), and 8-299 days (range). The differences were not statistically significant. Age distributions in both outcome groups showed a tendency of failures to occur more frequently in the first 2-4 months of life. The separate analysis of patients with idiopathic AS yielded similar figures and distributions. The data from the metaanalysis of the literature corresponded to our own results. CONCLUSION: There is a clear impact of age on ETV failure rate even when excluding etiological factors. The probability of ETV success gradually increases during the first months of life. The consequence of these findings for decision-making as well as parental counseling is to try to weigh the age of the infant and its estimated impact on ETV success with other factors guiding the decision to perform ETV or shunt in the treatment of obstructive hydrocephalus.

Age Distribution↗

Surgery in the tri-modality treatment of small cell lung cancer. Stage-dependent survival.

OBJECTIVE: Patients with small cell lung cancer (SCLC) are frequently denied surgical treatment despite growing body of evidence for a longer duration of remission and overall survival, if surgical intervention is integrated in a tri-modality therapy concept including chemotherapy, surgery, and radiotherapy. METHODS: A retrospective analysis was performed using data derived from 95 patients with SCLC operated upon over a period of 9 years. A subset of these patients was primarily operated upon and being diagnosed as SCLC only after thoracotomy, received radio-/chemotherapy postoperatively (n=64, group I). The second cohort had surgery after neoadjuvant chemotherapy which was continued postoperatively in addition to thoracic and cranial radiotherapy (n=31, group II). The patients in the second group were further divided into two subgroups: complete histological regression of tumor tissue in the mediastinal lymph nodes (group IIA), and those with persistent mediastinal lymph nodal involvement detected after thoracotomy (group IIB). RESULTS: Group I patients had stage I or II disease, whereas group II patients had clinical stage IIIA or IIIB. The overall 30-day mortality rate was as low as 5%. The median survival was 31.3 months for patients in group I, 31.7 months for adjuvant surgery with complete regression of mediastinal nodes (group IIA), and 12.4 months for adjuvant surgery without regression of mediastinal nodes (group IIB). CONCLUSIONS: Surgical intervention is promising and warrants prospective trials to be evaluated as an important adjunct to multi-modality therapy regimen in SCLC as regards to its impact on relapse free and overall survival.

Adult↗

The heterogeneity of human mesenchymal stem cell preparations--evidence from simultaneous analysis of proteomes and transcriptomes.

OBJECTIVE: Mesenchymal stem cells (MSC) raise high hopes in clinical applications. However, the lack of common standards and a precise definition of MSC preparations remains a major obstacle in research and application of MSC. Whereas surface antigen markers have failed to precisely define this population, a combination of proteomic data and microarray data provides a new dimension for the definition of MSC preparations. METHODS: In our continuing effort to characterize MSC, we have analyzed the differential transcriptome and proteome expression profiles of MSC preparations isolated from human bone marrow under two different expansion media (BM-MSC-M1 and BM-MSC-M2). RESULTS: In proteomics, 136 protein spots were unambiguously identified by MALDI-TOF-MS and corresponding cDNA spots were selected on our "Human Transcriptome cDNA Microarray." Combination of datasets revealed a correlation in differential gene expression and protein expression of BM-MSC-M1 vs BM-MSC-M2. Genes involved in metabolism were more highly expressed in BM-MSC-M1, whereas genes involved in development, morphogenesis, extracellular matrix, and differentiation were more highly expressed in BM-MSC-M2. Interchanging culture conditions for 8 days revealed that differential expression was retained in several genes whereas it was altered in others. CONCLUSION: Our results have provided evidence that homogeneous BM-MSC preparations can reproducibly be isolated under standardized conditions, whereas culture conditions exert a prominent impact on transcriptome, proteome, and cellular organization of BM-MSC.

Cell Culture Techniques↗

The CXCR4 antagonist AMD3100 releases a subset of G-CSF-primed peripheral blood progenitor cells with specific gene expression characteristics.

OBJECTIVE: AMD3100 is a new CXCR4 antagonist that induces a rapid release of hematopoietic progenitors from the bone marrow to the peripheral blood. We conducted a clinical study where patients with multiple myeloma and non-Hodgkin's lymphoma were treated with AMD3100 (A) to increase the number of peripheral blood progenitor cells (PBPCs) when given a mobilization regimen of granulocyte colony-stimulating factor (G-CSF, G). Because experimental data suggest that A+G-mobilized PBPCs are functionally different from G-mobilized PBPCs, we were interested in an intraindividual comparison of the gene expression profile of CD34+ cells in the two different settings. METHODS: To this end peripheral blood CD34+ cells of three patients (three G, three A+G samples) were isolated by immunomagnetic followed by flow cytometric sorting to a purity of >99%. Total RNA was purified. Differentially expressed genes were analyzed by using the Affymetrix GeneChip Human Genome U133 Plus2.0 and the software package Micro Array Solutions 1.3 (SAS Institute Inc.). RESULTS: We found a pattern of unanimously higher (81 genes, log2 ratio > 0.5; p < 0.0001) or lower (29 genes, log2 ratio < -0.4; p < 0.0001) expressed genes in the A+G-mobilized vs G-mobilized CD34+ PBPCs. Significant changes of four selected genes noted in the microarray analysis were validated by quantitative real-time polymerase chain reaction. Genes were grouped according to gene function. Only increased expression was found in the categories antiapoptosis (e.g., MPO, HSPA1B), cell cycle (e.g., MS4A3, RRM2), replication/DNA repair (e.g., MPO, HSPA1B), cell motility (e.g., TNFSF4, HMMR), and oxygen transport. Decreased expression occurred in the proapoptosis gene group (e.g., MDA5, BCL10). CXCR4 receptor gene expression itself was significantly 1.5-fold higher in the A+G vs G group. CONCLUSION: We conclude that A+G-mobilized CD34+ PBPCs express significantly higher amounts of genes that potentially promote superior engraftment after myeloablative therapy than G-mobilized CD34+ PBPCs.

Benzylamines↗

Betahistine: a retrospective synopsis of safety data.

Betahistine is a structural analogue of histamine that is prescribed for the treatment of vestibular disorders such as Ménière's disease and the symptomatic treatment of vertigo. It is estimated from sales information that >130 million patients have been exposed to the drug since its registration in 1968. In this review we analyse the safety profile of betahistine based on data obtained during >35 years of worldwide postmarketing surveillance. Until 31 December 2005, 554 adverse drug reaction (ADR) reports with 994 individual signs and symptoms were received by the marketing authorisation holder from worldwide sources and were reviewed and evaluated. Signs and symptoms of cutaneous hypersensitivity reactions during betahistine therapy were the most frequently reported complaints. They consisted of usually mild and self-limiting rash, pruritus and urticaria, and all symptoms were reversible after drug discontinuation. Betahistine was reported to be involved in one anaphylactoid reaction and one case of Stevens-Johnson syndrome. Anaphylactic reactions with fatal outcome were not reported. The reports that describe gastrointestinal complaints mostly concern nausea and vomiting or unspecific abdominal pain. These were typically non-serious complaints. Hepatobiliary involvement was reported 25 times, including increases in alkaline phosphatase, gamma-glutamyltransferase, and alanine and aspartate aminotransferase levels. None of the patients concerned developed severe liver failure or died. ADRs related to the nervous system predominantly reveal heterogeneous events that are not suggestive of a specific adverse reaction profile for betahistine. A clinical intolerance to betahistine that gave rise to asthma or bronchospasm was only reported in eight ADRs. A total of three cases of neoplasm have been reported. One case concerned a male patient of unknown age who experienced weight loss, insomnia, impatience and irritability soon after the start of betahistine therapy. An undiagnosed phaeochromocytoma was suspected. The remaining two cases were assessed as being unrelated to betahistine by the reporter. Finally, four deaths have been reported during the course of postmarketing surveillance for betahistine. The reporter assessed the causal relationship to betahistine in two as unrelated, in one as unlikely and the other as unassessable. In summary, clinical and postmarketing studies have revealed a good safety profile of betahistine that was confirmed by the safety surveillance data presented.

Adverse Drug Reaction Reporting Systems↗

Adoptive T cell therapy of solid cancers.

The development of immune-based approaches for the treatment of cancer has been actively investigated for many years. One strategy that has emerged as a potentially effective strategy for the treatment of aggressive established malignancies is adoptive T cell therapy. The power of this approach has been repeatedly observed in preclinical animal models. However, moving from homogeneous animal models to the heterogeneous human clinical setting has been very difficult. It is only in recent times that we have been able to pinpoint the problems of the clinical translation of adoptive T cell therapy. Some of the major problems are sources of tumor-specific T cells, ex vivo expansion, persistence, and anti-tumor activity. This review overviews the nature of these problems and some of the emerging solutions.

Animals↗

Association of retinal vasculitis (Eales' disease) and Meniere-like vestibulocochlear symptoms.

The objective of this study was to present a previously unknown association of visual loss and Meniere-like vestibuloauditory symptoms in Eales' disease (idiopathic retinal vasculitis) and to give a survey of other conditions affecting both the retina and inner ear. A 32-year-old man diagnosed with Eales' disease presented with recurrent deteriorations of visual acuity and simultaneous recurrent vestibuloauditory symptoms strongly reminiscent of Meniere's disease. Both the recurrent low frequency hearing losses and the losses of visual acuity could be restituted repeatedly by high dose i.v. corticosteroids. A literature review reveals that in a number of other retinopathic diseases associated with Meniere-like symptoms, microvasculopathy is also the pathomechanism. A common pathogenetic cause, e.g., autoimmune-mediated microvasculitis of retinal periphlebitis and vestibulocochlear symptoms, in this case is suggested. The presented case adds new evidence to microvasculopathy being a pathogenetic factor in Meniere's disease. In cases of coincidence of vestibulocochlear symptoms and retinal perivasculitis, a therapeutic attempt with high-dose corticosteroids is advisable.

Adult↗

Hematopoietic progenitor cells and cellular microenvironment: behavioral and molecular changes upon interaction.

Cell-cell contact between stem cells and cellular determinants of the microenvironment plays an essential role in controlling cell division. Using human hematopoietic progenitor cells (CD34+/CD38-) and a stroma cell line (AFT024) as a model, we have studied the initial behavioral and molecular sequel of this interaction. Time-lapse microscopy showed that CD34+/CD38- cells actively migrated toward and sought contact with stroma cells and 30% of them adhered firmly to AFT024 stroma through the uropod. CD44 and CD34 are colocalized at the site of contact. Gene expression profiles of CD34+/CD38- cells upon cultivation with or without stroma for 16, 20, 48, or 72 hours were analyzed using our human genome cDNA microarray. Chk1, egr1, and cxcl2 were among the first genes upregulated within 16 hours. Genes with the highest upregulation throughout the time course included tubulin genes, ezrin, c1qr1, fos, pcna, mcm6, ung, and dnmt1, genes that play an essential role in reorganization of the cytoskeleton system, stabilization of DNA, and methylation patterns. Our results demonstrate directed migration of CD34+/CD38- cells toward AFT024 and adhesion through the uropod and that upon interaction with supportive stroma, reorganization of the cytoskeleton system, regulation of cell division, and maintenance of genetic stability represent the most essential steps.

Animals↗

Comparative characteristics of mesenchymal stem cells from human bone marrow, adipose tissue, and umbilical cord blood.

OBJECTIVE: Various preparative protocols have been proposed for the acquisition and cultivation of mesenchymal stem cells (MSC). Whereas surface antigen markers have failed to precisely define this population, microarray analysis might provide a better tool for characterization of MSC. METHODS: In this study, we have analyzed global gene expression profiles of human MSC isolated from adipose tissue (AT), from umbilical cord blood (CB), and from bone marrow (BM) under two growth conditions and have compared them to terminally differentiated human fibroblasts (HS68). Profiles were compared using our Human Genome Microarray representing 51.144 different cDNA clones. RESULTS: Cultured with the appropriate conditions, osteogenic and adipogenic differentiation could be confirmed in all MSC preparations but not in fibroblasts. No phenotypic differences were observed by flow cytometry using a panel of 22 surface antigen markers. Whereas MSC derived from different donors using the same culture procedure yielded a consistent and reproducible gene expression profile, many genes were differentially expressed in MSC from different ontogenetic sources or from different culture conditions. Twenty-five genes were overlapping and upregulated in all MSC preparations from AT, CB, and BM as compared to HS68 fibroblasts. These genes included fibronectin, ECM2, glypican-4, ID1, NF1B, HOXA5, and HOXB6. Many genes upregulated in MSC are involved in extracellular matrix, morphogenesis, and development, whereas several inhibitors of the Wnt pathway (DKK1, DKK3, SFRP1) were highly expressed in fibroblasts. CONCLUSION: Our results have provided a foundation for a more reproducible and reliable quality control using genotypic analysis for defining MSC.

Adipose Tissue↗

Seizure freedom with different therapeutic regimens in intellectually disabled epileptic patients.

BACKGROUND: Epilepsy is a frequent condition in persons with intellectual disability and is more often difficult to treat than in the average population. Seizure freedom is the primary therapeutic goal which has important implications for the patient's quality of life. The aim of this study was to find out which antiepileptic therapy regimens (monotherapy or combination therapy) are effective in achieving this goal in intellectually disabled epilepsy patients. We were especially interested in the impact of the new antiepileptic drugs (AEDs) which were introduced during the past decade. METHOD: We investigated retrospectively the antiepileptic regimens on which the resident patients of a large epilepsy centre (as a rule with additional intellectual disabilities of different degrees) were seizure free in 2002. Information on antiepileptic medication and seizure frequency was taken out of the individual case documentation. It was also determined whether seizure free patients had already been seizure free in 1992. RESULTS: Two hundred and forty out of 675 patients (35,6%) with epilepsy were seizure free. The proportion of seizure freedom was 43,7% in patients with borderline intelligence, 39,2% in mild, 33,2% in moderate, 31,9% in severe, and 21,9% in profound intellectual disability. One hundred and twenty-two (50,8%) seizure free patients were on monotherapy; 53 of them were on CBZ (PB: 34, VPA: 25, PHT: 7, LTG: 3). Ninety-three patients (38,7%) were on duotherapies, CBZ/PB (27 patients), PB/PHT (17), and LTG/VPA (14) being the commonest. Of 18 (7,5%) triple therapies, LTG/PB/VPA (4 patients) was the commonest. Taken together, the five most frequent therapeutic regimens were CBZ monotherapy, PB monotherapy, CBZ/PB, VPA monotherapy and PB/PHT (a clear preponderance of classic AEDs). A distinction was made between "old seizure free" (seizure free already in 1992) and "new seizure free" (in 1992 still seizures) patients. In the 132 old seizure free patients the classic AEDs prevailed again, monotherapies with CBZ, PB and VPA being the most frequent regimens. In comparison, in the 78 new seizure free patients the novel combination LTG/VPA was the third most frequent, after the classic regimens CBZ/PB and CBZ; PB monotherapies were rare. CONCLUSION: In a majority of intellectually disabled patients with epilepsy (including those who became seizure free since 1992), complete seizure control has been achieved by monotherapy or duotherapy with classic AEDs. Of the new AEDs LTG in combination with VPA appears to be an important innovation.

Adolescent↗

Evidence for a bipolar change in distortion product otoacoustic emissions during contralateral acoustic stimulation in humans.

The aim of this study was to investigate the activity of the medial olivocochlear (MOC) efferents during contralateral (CAS) and ipsilateral acoustic stimulation (IAS) by recording distortion product otoacoustic emission (DPOAE) suppression and DPOAE adaptation in humans. The main question was: do large bipolar changes in DPOAE level (transition from enhancement to suppression) also occur in humans when changing the primary tone level within a small range as described by Maison and Liberman for guinea pigs [J. Neurosci. 20, 4701-4707 (2000)]? In the present study, large bipolar changes in DPOAE level (14 dB on average across subjects) were found during CAS predominantly at frequencies where dips in the DPOAE fine structure occurred. Thus, effects of the second DPOAE source might be responsible for the observed bipolar effect. In contrast, comparable effects were not found during IAS as was reported in guinea pigs. Reproducibility of CAS DPOAEs was better than that for IAS DPOAEs. Thus, contralateral DPOAE suppression is suggested to be superior to ipsilateral DPOAE adaptation with regard to measuring the MOC reflex strength and for evaluating the vulnerability of the cochlea to acoustic overexposure in a clinical context.

Acoustic Stimulation↗

Retroviral integration sites correlate with expressed genes in hematopoietic stem cells.

In this study, we analyzed whether retroviral integration sites in repopulating hematopoietic cells correlate with genes expressed in fractions enriched in hematopoietic stem cells (HSCs). We have previously described microarray studies of two populations enriched in HSCs: CD34+/CD38- and the slow dividing fraction of CD34+/CD38- cells (SDF). Furthermore, we demonstrated that oncoretroviral integrations in severe combined immunodeficient repopulating cells are preferentially located near the transcription start. Here, we have identified 117 corresponding cDNA clones on our micro-array representing genes with retroviral integration sites. These genes revealed a higher mean signal intensity in comparison with either all genes on the array or a subset of control genes with retroviral integrations in HeLa cells. Furthermore, these genes demonstrated a higher expression in CD34+/CD38- cells and SDF. The association of gene expression and retrovirally targeted genes observed here will help to elucidate the molecular characteristics of primitive repopulating hematopoietic cells.

Animals↗

Mechanisms of failure after endoscopic third ventriculostomy in young infants.

OBJECT: The cause of failed endoscopic third vetriculostomy (ETV) surgery in the treatment of hydrocephalus may be a poor absorption of cerebrospinal fluid (CSF) or a new or continuing obstruction of CSF pathways. Particularly in infants, ETV failures often are ascribed to a still poorly developed CSF absorptive capacity. METHODS: The authors report on a series of 11 infants younger than 1 year of age undergoing at least one repeated endoscopic surgery after a failed initial ETV for aqueductal stenosis. The following three patterns of endoscopic findings were observed: 1) reclosure of the ventriculostoma; 2) narrowing of the ventriculostoma; and 3) patent ventriculostoma with new arachnoid membranes in the basal cisterns below the floor of the third ventricle, not present at the time of the first ETV. In all patients, a new obstruction of CSF pathways was seen during repeated ETV or shunt surgery. CONCLUSIONS: The authors' data strongly suggest that CSF pathway reclosure is the factor most responsible for ETV failure in obstructive hydrocephalus. According to both their experiences and to studies published in the literature, the formation of new arachnoid membranes or scars plays a far greater role in ETV failure than does poor CSF absorption, at least in aqueductal stenosis. It is hypothesized that infants have a higher tendency to form new arachnoid membranes than do older patients and that this factor may explain (at least in part) the higher ETV failure rate in patients younger than 1 year old.

Arachnoid↗