Publications by authors named "Marjan J Jongsma"

The present study evaluates neuroprotection in a marmoset MPTP (1-methyl-1,2,3,6-tetrahydropyridine) model representing early Parkinson's disease (PD). The anti-glutamatergic compound riluzole is used as a model compound for neuroprotection. The compound is one of the few protective compounds used in the clinic for a neurodegenerative disorder.

View Article and Find Full Text PDF

Study Objectives: Sleep problems are a common phenomenon in most neurological and psychiatric diseases. In Parkinson disease (PD), for instance, sleep problems may be the most common and burdensome non-motor symptoms in addition to the well-described classical motor symptoms. Since sleep disturbances generally become apparent in the disease before motor symptoms emerge, they may represent early diagnostic tools and a means to investigate early mechanisms in PD onset.

View Article and Find Full Text PDF

Current therapies for Parkinson's disease (PD) like l-dopa and dopamine (DA) agonists have declined efficacy after long term use. Therefore, research towards supplementary or alternative medication is needed. The implementation in PD can be expedited by application of compounds already used in the clinic.

View Article and Find Full Text PDF

Background And Purpose: The effects of sleep deprivation are a burden in our 24-h society. The use of wake-promoting compounds could improve the performance in situations where sleep cannot be allowed. In this study, the efficacy of the wake-promoting compounds, modafinil and caffeine, in counteracting the effects of 24-h sleep deprivation in the marmoset monkey were tested.

View Article and Find Full Text PDF
Article Synopsis
  • Modafinil shows protective effects against brain injury and behavior changes in a marmoset model of Parkinson's disease caused by 1-methyl-1,2,3,6-tetrahydropyridine.
  • Daily treatment with modafinil (100 mg/kg) over 27 days significantly reduced the negative impacts on behavior, locomotor activity, and hand-eye coordination compared to a vehicle control group.
  • Additionally, dopamine levels in the striatum were much higher in the modafinil-treated group, indicating that modafinil may be an effective treatment option for managing symptoms associated with Parkinson's disease.
View Article and Find Full Text PDF
Article Synopsis
  • Modafinil is being explored not just for enhancing alertness in sleep disorders and neurodegenerative diseases, but also for its potential benefits in healthy individuals, leading to a need for more research on its behavioral effects.
  • Observational methods and behavioral tests were conducted on marmoset monkeys to assess modafinil's impacts on various behaviors after administering different doses.
  • Results indicated that modafinil increased locomotor activity and exhibited anxiolytic-like effects without causing side effects or affecting hand-eye coordination or startle response, suggesting new therapeutic possibilities for its use.
View Article and Find Full Text PDF

Nevi and melanomas correlate to childhood and intermittent solar UV exposure, xeroderma pigmentosum patients run increased risk, and p16(Ink4a) expression is often lost in malignant progression. To ascertain the effect of these risk factors, pigmented hairless Ink4a/Arf-, Xpa- knockout mice were subjected to various combinations of neonatal [7,12-dimethylbenz(a)anthracene (DMBA) or UVB exposure] and adult treatments (12-O-tetradecanoylphorbol-13-acetate or subacute daily UVB exposure or intermittent overexposure). Nevi occurred earliest, grew largest, and were most numerous in mice exposed to DMBA followed by intermittent UVB overexposure [effect of six minimal edemal doses (MED), 1 x /2 weeks > 4 MED 1 x /wk].

View Article and Find Full Text PDF

Overexposure to short- and long-wave ultraviolet radiations (UVB, UVA) may contribute to melanoma development through combined genotoxic and mitogenic effects in melanocytes. This study compares the impact of UVA-1 versus UVB, and single versus fractionated exposures on melanocyte proliferation in hairless SKH-2 mice. A single erythemal dose was compared with an equal dose fractionated over 8 d, and dose-dependency was studied.

View Article and Find Full Text PDF