Pathological inclusions containing fibrillar aggregates of hyperphosphorylated tau protein are a characteristic feature in tauopathies, which include Alzheimer's disease (AD). Tau is a microtubule-associated protein whose transcript undergoes alternative splicing in the brain. Exon 10 encodes one of four microtubule-binding repeats. Exon 10 inclusion gives rise to tau protein isoforms containing four microtubule-binding repeats (4R) whereas exclusion leads to isoforms containing only three repeats (3R). The ratio between 3R and 4R isoforms is tightly controlled via alternative splicing in the human adult nervous system and distortion of this balance results in neurodegeneration. Previous studies showed that several splicing regulators, among them hTRA2-beta1 and CLK2, regulate exon 10 alternative splicing. Like most splicing factors, htra2-beta and clk2 pre-mRNAs are regulated by alternative splicing. Here, we investigated whether human postmortem brain tissue of AD patients reveal differences in alternative splicing patterns of the tau, htra2-beta, presenilin 2 and clk2 genes when compared with age-matched controls. We found that the splicing patterns of all four genes are altered in affected brain areas of sporadic AD patients. In these affected areas, the amount of mRNAs of tau isoforms including exon 10, the htra2-beta1 isoform and an inactive form of clk2 are significantly increased. These findings suggest that a misregulation of alternative splicing seems to contribute to sporadic AD.
In this present study 31 schizophrenic patients were treated for six months for relapse prevention under double-blind conditions with either haloperidol decanoate (22) or fluphenazine decanoate (9). In respect of the prophylactic action, both depot neuroleptics proved to be equal during the comparatively short period of observation. In both groups a psychotic relapse occurred that could not be managed by increasing the depot dosage. No side-effects worth mentioning appeared in either group of patients; patients under haloperidol decanoate, however, only required half the quantity of anti-parkinson medication as compared with patients treated with fluphenazine decanoate, and also displayed extrapyramidal motor symptoms (EPMS) to a lesser degree. Patients received a mean monthly injection of 80 mg of Haloperidol, reaching steady-state serum levels of about 3 ng/ml in the third injection interval. Fluphenazine serum levels known so far for seven patients amount to 0.8 ng/ml after fluphenazine injections of 21 mg every 14 days.
Baseline severity may be only one of many other important clinical variables that mediate clinical outcome, but it is surely an important one deserving further research and consideration.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.