Biomedical subjects

E Bahn

Publications and source records attributed to E Bahn.

At least 19 recordsLinked to original sources

PubMed2006

TorsinB expression in the developing human brain.

Familial, early onset, generalized torsion dystonia is the most common and severe primary dystonia. The majority of cases are caused by a 3-bp deletion (GAG) in the coding region of the DYT1 (TOR1A) gene. The cellular and regional distribution of torsinA protein, which is restricted to neuronal cells and present in all brain regions by the age of 2 months has been described recently in human developing brain. TorsinB is a member of the same family of proteins and is highly homologous with its gene adjacent to that for torsinA on chromosome 9q34. TorsinA and torsinB share several remarkable features suggesting that they may interact in vivo. This study examined the expression of torsinB in the human brain of fetuses, infants and children up to 7 years of age. Our results indicate that torsinB protein expression is temporarily and spatially regulated in a similar fashion as torsinA. Expression of torsinB protein was detectable beginning at four to 8 weeks of age in the cerebellum (Purkinje cells), substantia nigra (dopaminergic neurons), hippocampus and basal ganglia and was predominantly restricted to neuronal cells. In contrast to torsinA, torsinB immunoreactivity was found more readily in the nuclear envelope. High levels of torsinB protein were maintained throughout infancy, childhood and adulthood suggesting that torsinB is also needed for developmental events occurring in the early postnatal phase and is necessary for functional activity throughout life.

Adult↗

PubMed2005

TorsinA expression is detectable in human infants as young as 4 weeks old.

Familial, early onset, generalized torsion dystonia is the most common and severe primary dystonia. The majority of cases are caused by a 3-bp deletion (GAG) in the coding region of the DYT1 (TOR1A) gene. The cellular and regional distribution of torsinA protein and its message has been described previously in several regions of normal adult human and rodent brain. This study examines the expression of torsinA in the developing human brain of fetuses, infants and children up to 7 years of age in four selected brain regions. Expression of torsinA protein was detectable beginning at 4 to 8 weeks of age postnatally in the cerebellum (Purkinje cells), substantia nigra (dopaminergic neurons), hippocampus and basal ganglia. Prominent torsinA immunoreactivity was not seen before 6 weeks of age postnatally, a period associated with synaptic remodeling, process elimination and the beginning of myelination. Our results indicate that torsinA protein expression is temporally and spatially regulated and is present in all brain regions studied by the age of 2 months on into adulthood.

Adult↗

PubMed2002

Specific 14-3-3 isoform detection and immunolocalization in prion diseases.

14-3-3 proteins are involved in signalling processes in neuronal cells. Using isoform-specific antibodies we have examined the variation in 14-3-3 isoform neurolocation in normal and scrapie-infected murine brain and show that in defined areas of the brain there are significant changes associated with the pathology of the disease process. The appearance of 14-3-3 proteins in the cerebrospinal fluid (CSF) is a consequence of neuronal disease and the detection of specific isoforms of the 14-3-3 proteins in the CSF is characteristic of some neurodegenerative diseases. In this study, monitoring specifically for the gamma 14-3-3 isoform in the CSF by both Western-blot analysis and ELISA we can show a level of correlation between the assays.

14-3-3 Proteins↗

PubMed2000

Boxing and running lead to a rise in serum levels of S-100B protein.

Permanent neurological dysfunction is the primary medical concern of boxing. Recently it was reported that patients presenting elevated levels of the glial protein S-100B in serum after minor head injuries are more prone to develop neuropsychological deficits than patients with lower levels of S-100B protein. We assessed this protein before and after amateur boxing competitions (n = 10) and sparring bouts (n = 15). In several control groups, we investigated S-100B levels of participants before and after a 25 km race (n = 11), jogging (10 km, n = 12), short-term running (n = 12), and heading footballs (n = 12). There was an increase in S-100B protein after boxing and the running disciplines but not after ergometer cycling or soft heading of footballs. The increase in S-100B protein concentrations due to competitive boxing and after the 25 km race was significantly higher than that after performing other disciplines (p < 0.001). There was no significant difference between the increases caused by sparring and the running disciplines (p = 0.21). The number and severity of the strikes to the head correlated significantly with the increase in the S-100B protein levels. Levels of S-100B protein known to be associated with neuropsychological deficits were not reached in our study. In professional boxing, much higher levels are to be expected and would be worthy of investigation.

Adolescent↗

PubMed1999

Sleep disorders and portal-systemic encephalopathy following transjugular intrahepatic portosystemic stent shunt in patients with liver cirrhosis. Relation to plasma tryptophan.

Neuropsychiatric symptoms due to any type of dysfunction and/or portal-systemic shunting are summarized as hepatic encephalopathy (HE). HE in the presence of liver cirrhosis and/or portal-systemic shunting has been termed portal-systemic encephalopathy (PSE). PSE is most frequent among the HE syndromes and is almost exclusively seen in patients with advanced cirrhosis and portal hypertension. Portal-systemic shunting either spontaneous due to portal hypertension, following surgical portocaval anastomosis, or subsequent to transjugular intrahepatic portosystemic stent-shunt (TIPSS) is regarded as the primary causative condition for PSE, not hepatic dysfunction per se. PSE may be considered as a disorder of multiple neurotransmitter systems among which derangements of the serotonergic system have been documented most consistently. Incipient PSE is frequently paralleled by the occurrence of sleep disorders, however, their relation to PSE remains unclear. We observed a transient increase of sleep disorders post-TIPSS, which were only in part correlated to other symptoms of PSE. Among the biochemical parameters studied only an association between arterial ammonia levels and sleep disorders became apparent, whereas no significant relation was observed for peripheral tryptophan.

Adult↗

PubMed1999

A synthetic combination of mutations, including fs(1)pyrSu(b), rSu(b) and b, causes female sterility and reduces embryonic viability in Drosophila melanogaster.

A Drosophila melanogaster mutant, fs(1)pyrSu(b), carrying a mutation that maps to the tip of the X chromosome, has been isolated. The mutation, when present alone, does not confer a detectable phenotype. However, this mutation causes female sterility and reduces embryonic viability when combined with mutations which deregulate the pyrimidine and beta-alanine pools. Embryos that are homozygous for the mutations fs(1)pyrSu(b), rSu(b) [previously designated as Su(b)] and b, and originate from a female parent homozygous for the three mutations show severely reduced viability. Newly laid eggs begin development normally, but the majority of the embryos die just before the eggs are due to hatch.

Alleles↗

PubMed1999

Elevated serum levels of astroglial S100beta in patients with liver cirrhosis indicate early and subclinical portal-systemic encephalopathy.

Portal-systemic encephalopathy is the prototype among the neuropsychiatric disorders that fall under the term Hepatic Encephalopathies. Ammonia toxicity is central to the pathophysiology of Portal-systemic encephalopathy, and neuronal ammonia toxicity is modulated by activated astrocytes. The calcium-binding astroglial key protein S100beta is released in response to glial activation, and its measurement in serum only recently became possible. Serum S100beta was determined by an ultrasensitive ELISA in patients (n=36) with liver cirrhosis and transjugular intrahepatic portosystemic stent-shunt. Subclinical portal-systemic encephalopathy and overt portal-systemic encephalopathy were determined by age-adjusted psychometric tests and clinical staging, respectively. Serum S100beta, was specifically elevated in the presence of subclinical or early portal-systemic encephalopathy, but not arterial ammonia. S100 levels elevated above a reference value (S100beta < or = 110pg/ml) or the cut off value determined in our group of patients (112pg/ml) predicted subclinical portal-systemic encephalopathy with a specificity and sensitivity of 100 and 56.5%, respectively. Serum S100beta was significantly dependent on liver dysfunction (Child-Pugh score), but was more closely related to cognitive impairments than the score. Serum S100beta seems to be a promising biochemical surrogate marker for mild cognitive impairments due to portal-systemic encephalopathy.

Astrocytes↗

PubMed1999

Isoform pattern of 14-3-3 proteins in the cerebrospinal fluid of patients with Creutzfeldt-Jakob disease.

Two-dimensional polyacrylamide gel electrophoresis of CSF has been used in the diagnosis of Creutzfeldt-Jakob disease (CJD). One of the two diagnostic protein spots was identified as isoform(s) of the 14-3-3 family of abundant brain proteins. This has led to the development of one-dimensional 14-3-3 sodium dodecyl sulfate polyacrylamide gel electrophoresis immunoblot, which is currently used to support the diagnosis of CJD. In the present study employing western blot analysis, we have identified the panel of 14-3-3 isoforms that appear in the CSF of 10 patients with CJD compared with 10 patients with other dementias. The results clearly show that the 14-3-3 isoforms beta, gamma, epsilon, and eta are present in the CSF of patients with CJD and can be used to differentiate other dementias. 14-3-3eta also gave a baseline signal in all patients with other dementias, including six patients with Alzheimer's disease. The presence of 14-3-3eta in the CSF of a patient with herpes simplex encephalitis was particularly noteworthy. This study has determined that isoform-specific 14-3-3 antibodies against beta, gamma, and epsilon should be considered for the neurochemical differentiation of CJD from other neurodegenerative diseases.

14-3-3 Proteins↗

PubMed1999

Late increase of serum S100 beta protein levels in hamsters after oral or intraperitoneal infection with scrapie.

Following recent reports of elevated serum S100 beta protein (S100 beta) levels in patients with genetic and sporadic Creutzfeldt-Jakob disease and in rodents parenterally infected with scrapie, the suitability of serum S100 beta as a preclinical marker for transmissible spongiform encephalopathies was assessed in time-course studies. Syrian hamsters were orally and intraperitoneally challenged with scrapie and assayed for serum S100 beta levels at various times after infection. Although elevated serum S100 beta levels were consistently observed in terminally ill animals for both routes of infection, the experiments failed to detect significantly increased S100 beta serum concentrations prior to the manifestation of clinical symptoms. Thus, in this animal model, serum S100 beta does not appear to be an appropriate marker for the preclinical detection of scrapie, but it may provide a convenient laboratory aid for the diagnosis of transmissible spongiform encephalopathy in naturally or accidentally infected animals and humans.

Administration, Oral↗

PubMed1998

Decrease of S100 beta protein in serum of patients with amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease of unknown origin characterized by loss of upper and lower motor neurons and concomitant astrogliosis. We have investigated the S100 beta protein levels in serum as a marker for astroglia of patients with ALS (n = 41) in comparison to a control group (n = 32). Additionally we have investigated 12 patients at different follow-up time points (minimum 6 months). We could not observe a significant difference of S100 beta protein in patients with ALS in comparison to our control group (P = 0.11) but we could clearly see a decrease of S100 beta levels in the further course of the disease. As S100 beta is also seen as a protein with nerve growth factor activity we assume that the fall of serum levels may reflect the loss of nerve growth stimulation in patients with ALS and suppose that repetitive measurements of S100 beta in serum can be used as an objective marker for disease progression.

Aged↗

PubMed1998