Biomedical subjects

C Albrecht

Publications and source records attributed to C Albrecht.

60 records · Page 4Linked to original sources

PubMedDate not supplied

Muscarinic acetylcholine receptors activate the acetylcholinesterase gene promoter.

The acetylcholinesterase (AChE) gene promoter contains several overlapping binding sites for Sp1 and Egr-1 transcription factors. Cotransfection experiments and promoter assays showed that Egr-1 can potently activate transcription from the human AChE promoter. Muscarinic acetylcholine receptors (mAChR) rapidly activate, via protein kinase C-mediated signaling, expression of the Egr-1 gene, leading to dramatically increased nuclear concentrations of Egr-1 protein, and to increased binding of Egr-1 to specific DNA recognition sequences. These mAChR-induced increases are followed by increased transcription from the human AChE promoter. In vivo studies with intraventricular infusions of the cholinergic immunotoxin 192 IgG saporin showed more than 80% decrease of AChE activity in cholinergic target areas of the hippocampus and brain cortex. The results are compatible with a combination of decreased AChE activity in degenerating subcortical cholinergic projections, and additional decreases in postsynaptic AChE gene expression. Together our data show that mAChR can activate transcription from the AChE promoter via increased synthesis of Egr-1. The results suggest a feedback mechanism by which the AChE gene is activated by cholinergic neurotransmission, possibly leading to increased formation of AChE protein and accelerated degradation of acetylcholine at cholinergic synapses. This possibility suggests testing of cholinomimetic compounds currently in development for the treatment of Alzheimer's disease for their potential ability to increase AChE gene expression.

Acetylcholinesterase↗

PubMedDate not supplied

[Inpatient rehabilitation of patients following total hip replacement--a study using the Harris hip score].

AIMS: The aim of the study was to evaluate the outcome of inpatient rehabilitation following total hip arthroplasty using the Harris hip score. Factors influencing the result were analysed. METHOD: 338 patients admitted to a rehabilitation unit after total hip replacement were included in a prospective study. There were 252 female and 86 male patients, with a mean age of 69 (+/- 9.7) years (range, 34 to 88 years). RESULTS: At admission the Harris hip score was 63.1 (+/- 10.4) and was improved by almost 25 % to 79.1 (+/- 7.1) at discharge. The percentage of patients with a poor score was decreased from 71.9 % to 8 % after rehabilitation. The result of rehabilitation was independent of sex, age, concomitant diagnoses or weight bearing. 61 patients could not be discharged after three weeks as usual and stayed for another 8.0 (+/- 4.5) days. At admission these patients had significantly lower scores (58.5 +/- 10.8) than the patients who stayed for three weeks (64.1 +/- 10.0). At discharge scores were comparable with 77.0 (+/- 7.2) and 79.6 (+/- 7.0), respectively. CONCLUSION: An inpatient rehabilitation after hip arthroplasty significantly improves the Harris hip score independent of sex, age, concomitant diseases and weight bearing.

Activities of Daily Living↗

PubMedDate not supplied

[Outcome of inpatient rehabilitation following total knee replacement using the HSS-Score].

AIMS: The aim of the study was to evaluate the outcome of inpatient rehabilitation following total knee arthroplasty using the HSS score (Hospital for Special Surgery). Factors influencing the result were analysed. METHOD: 182 patients admitted to a rehabilitation unit after total knee replacement were included. There were 146 female and 36 male patients, with mean age of 72 (+/- 6.1) years (range; 49 to 84 years). RESULTS: At admission, the HSS score was 47.4 (+/- 10.6) and was significantly improved to 69.8 (+/- 8.8) at discharge. The percentage of patients with a poor result was markedly decreased from 86.8 % to 10.4 %. The outcome was independent of sex, age, concomitant diseases or postoperative weight bearing. 34 patients could not be discharged after 3 weeks as usually and stayed for another 8.3 (+/- 2.6) days. These patients had significantly lower scores at admission (41.9 +/- 11.2) than patients who stayed for three weeks (48.6+/- 10.1). At discharge, scores were comparable with 67.7 (+/- 9.4) and 70.2 (+/- 8.6), respectively. CONCLUSION: Inpatient rehabilitation following knee arthroplasty significantly improved the HSS score independent of sex, age, concomitant diseases and weight bearing.

Activities of Daily Living↗

PubMedDate not supplied

Adrenocorticotropin widens the focus of attention in humans. A nonliner electroencephalographic analysis.

OBJECTIVE: This study examined the effects of ACTH 4-10, a fragment of adrenocorticotropin (ACTH) with known central nervous system (CNS) activity, on the dimensional complexity of the ongoing electroencephalographic (EEG) activity. Stressful stimuli cause ACTH to be released from the pituitary, and as a neuropeptide ACTH may concurrently exert adaptive influences on the brain's processing of these stimuli. Previous studies have indicated an impairing influence of ACTH on selective attention. METHODS: Dimensional complexity of the EEG, which indexes the brain's way of stimulus processing, was evaluated while subjects performed tasks with different attention demands. Sixteen healthy men (23 to 33 years) were tested once after placebo and another time after administration of ACTH 4-10 (1.25 mg intravenously (i.v.), 30 minutes before testing). The EEG was recorded while subjects were presented with a dichotic listening task (consisting of the concurrent presentation of tone pips to the left and right ear). Subjects either a) listened to pips in both ears (divided attention), or b) listened selectively to pips in one ear (selective attention), or c) ignored all pips. RESULTS: Dimensional complexity of the EEG was higher during divided than selective attention. ACTH significantly increased the EEG complexity during selective attention, in particular over the midfrontal cortex (Fz, Cz). CONCLUSIONS: The effects support the view of a de-focusing action of ACTH during selective attention that could serve to improve the organism's adaptation to stress stimuli.

Adrenocorticotropic Hormone↗

PubMedDate not supplied

Direct use of cell lysates in PCR-based diagnosis of bovine leukemia virus infection.

Polymerase chain reaction (PCR) has been used for direct detection of bovine leukemia virus (BLV) proviral DNA in cattle, but it is still mainly used for experimental research. One bottleneck for routine diagnosis of BLV by PCR has always been the isolation and purification of DNA. We compare the use of not purificated with highly-purified DNA in the PCR-based diagnosis of BLV infection. DNA extracted from whole blood by chloroform extraction (CP-DNA) and DNA prepared only by osmotic shock, washing, heating and freezing procedures (RPoS-DNA), were utilized. Fifteen cattle well characterized serologically were investigated for BLV-provirus with PCR using this different DNA preparations. With both methods all but one investigated animal were correctly identified. It was estimated that in case of CP-DNA PCR 10 BLV-provirus copies were sufficient to obtain a positive result. The sensitivity of RPoS-DNA PCR was similar. Because of the greater practicability of the latter technique we used it in a small field study with ten cattle. All serologically positive animals were correctly identified by the PCR. In addition one seronegative animal was found to carry BLV-provirus. Therefore RPoS-DNA PCR might be a good tool for the routine diagnosis of BLV-infected cattle.

Animals↗

PubMedDate not supplied

Heterogeneity of signal transduction mechanisms in human basophils and human skin mast cells. II. Effects of 7-O-methyl-UCN-01, NPC 15437 and bryostatin 1 and 2, four protein kinase C-modulatory agents, on mediator release.

Basophils and mast cells play a crucial role in immunological and allergic processes due to the release of inflammatory mediators such as histamine. It has been suggested for a long time that the histamine release (HR) from these cells is closely related to protein kinase (PKC) activity. However, the distinct role of PKC with its large variety of isozymes in different cell types and the actions of these isozymes in HR still remain unclear. Therefore, in the present study, we compared the effects of the two PKC inhibitors 7-O-methyl-UCN-01 (UCN-01-Me) and NPC 15437 as well as two PKC activators, bryostatin 1 and 2, on anti-IgE and Ca(2+)-ionophore-induced HR from human basophils and isolated human skin mast cells (HSMC). In both HSMC and basophils, anti-IgE-induced HR was inhibited by PKC inhibitor UCN-01-Me pre-incubation dose-dependently. In stark contrast, A23187-induced HR was unaffected by UCN-01-Me in both cell types. In our experiments, the inhibitory efficacy of the compound NPC 15437 on HR was much lower than that of UCN-01-Me and showed no statistical significance. Both bryostatins 1 and 2 produced good dose-dependent inhibition of HR from HSMC stimulated with anti-IgE, whereas HR from basophils was potentiated with these compounds. The same effects were observed with basophils stimulated with A23187, where potentiation of HR was up to fourfold of the control at the highest concentrations of bryostatins, while HSMC showed a slight decrease in HR compared to non-bryostatin-treated controls. Basophils and HSMC showed very clear differences in HR when directly stimulated with the bryostatins, since no HR was observed from HSMC while in basophils the HR increased up to 47% of total histamine at the highest concentrations of bryostatins (1 mumol/l). HR from basophils was observed to be strictly dose-dependent. The differences in the cell reactions of the two cell types incubated with these four compounds indicate distinct biochemical roles of PKC in the cascades leading to degranulation of the cells. Furthermore, the experiments with UCN-01-Me support the hypothesis of PKC-beta to play a substantial positive modulatory role for the degranulation of immunologically stimulated basophils.

Alkaloids↗