Browsing Research Output by Author "Du Preez, Jan L."
Now showing items 1-20 of 22
-
Cortico-striatal oxidative status, dopamine turnover and relation with stereotypy in the deer mouse
Güldenpfennig, Marianne; Wolmarans, De Wet; Du Preez, Jan L.; Harvey, Brian H.; Stein, Dan J. (Elsevier, 2011)The deer mouse presents with spontaneous stereotypic movements that resemble the repetitive behaviours of obsessive–compulsive disorder (OCD), and demonstrates a selective response to serotonin reuptake inhibitors. OCD has ... -
Corticolimbic changes in acetylcholine and cyclic guanosine monophosphate in the Flinders Sensitive Line rat: a genetic model of depression
Brand, Linda; Van Zyl, Jurgens; Minnaar, Estella L.; Viljoen, Francois; Du Preez, Jan L.; Harvey, Brian H. (Cambridge, 2012)Objective: Depression is suggested to involve disturbances in cholinergic as well as glutamatergic pathways, particularly the N-methyl-d-aspartate receptor-mediated release of nitric oxide (NO) and cyclic guanosine ... -
Development and validation of a single analytical method for the determination of tryptophan, and its kynurenine metabolites in rat plasma
Möller, Marisa; Du Preez, Jan L.; Harvey, Brian H. (Elsevier, 2012)It is highly beneficial to monitor the activity of the kynurenine pathway in a large series of samples with high accuracy and reliability in a single experimental protocol. We have developed a rapid specific solid-phase ... -
Effect of chronic N-acetyl cystine administration on oxidative status in the presence and absence of induced oxidative stress in rat striatum
Harvey, Brian H.; Joubert, Charise; Du Preez, Jan L.; Berk, Michael (Springer, 2008)Antioxidants have possible therapeutic value in neurodegenerative disorders, although they may have pro-oxidant effects under certain conditions. Glutathione (GSH) is a key free radical scavenger. N-acetylcysteine (NAC) ... -
The high performance liquid chromatography (HPLC) analysis of ultraviolet (UV) irradiated chlorophyll a and secondary plant compounds
Scheepers, Johanna C.; Malan, Sarel F.; Du Preez, Jan L.; Van Dyk, Sandra (Academic Journals, 2011)A large number of diseases such as cancer, cardiovascular disease, inflammatory disease, neurodegenerative disorders and ageing are consequences of reactive oxygen species (ROS) and reactive nitrogen species (RNS). ... -
In vitro anti-cancer effects of artemisone nano-vesicular formulations on melanoma cells
Dwivedi, Anupma; Mazumder, Anisha; Du Plessis, Lissinda; Du Preez, Jan L.; Haynes, Richard K.; Du Plessis, Jeanetta (Elsevier, 2015)Artemisone is a 10-amino-artemisinin derivative that is markedly superior in vitro and in vivo to current artemisinins against malaria and also possesses antitumor activity. In seeking to capitalise on the last property, ... -
In vitro skin permeation of artemisone and its nano-vesicular formulations
Dwivedi, Anupma; Mazumder, Anisha; Fox, Lizelle T.; Brümmer, Alicia; Gerber, Minja; Du Preez, Jan L.; Haynes, Richard K.; Du Plessis, Jeanetta (Elsevier, 2016)The artemisinin derivative artemisone has antitumor activity. In particular when encapsulated in solid lipid nanoparticles (SLNs) and niosomes, it is active against human melanoma A-375 cells, although such formulations ... -
In vitro wound healing and cytotoxic effects of sinigrin-phytosome complex
Mazumder, Anisha; Dwivedi, Anupma; Du Preez, Jan L.; Du Plessis, Jeanetta (Elsevier, 2016)Sinigrin is a class of glucosinolates found naturally in plants of the Brassicaceae family. Lately, studies have shown that sinigrin possesses anticancer, antibacterial and anti-inflammatory activities. Since its efficacy ... -
Isolation rearing-induced deficits in sensorimotor gating and social interaction in rats are related to cortico-striatal oxidative stress, and reversed by sub-chronic clozapine administration
Möller, Marisa; Du Preez, Jan L.; Harvey, Brian H.; Emsley, Robin (Elsevier, 2011)Social isolation rearing (SIR) in rats induces behavioral and glutamatergic changes akin to schizophrenia. We studied the effects of 8 weeks SIR on cortico-striatal redox and social and cognitive behaviors in rats. SIR ... -
N-acetyl cysteine reverses social isolation rearing induced changes in cortico-striatal monoamines in rats
Möller, Marisa; Du Preez, Jan L.; Viljoen, Francois P.; Harvey, Brian H.; Berk, Michael (Springer, 2013)Schizophrenia is causally associated with early-life environmental stress, implicating oxidative stress in its pathophysiology. N-acetyl cysteine (NAC), a glutathione precursor and antioxidant, is emerging as a useful ... -
A novel HPLC method developed and validated for the detection and quantification of atorvastatin, fluvastatin, pitavastatin and pravastatin during transdermal delivery studies
Maree, Sumari; Du Preez, Jan L.; Du Plessis, Lissinda H.; Du Plessis, Jeanetta; Gerber, Minja (Govi-Verlag, 2020)An HPLC method was developed and validated to quantify and identify several statins (atorvastatin, fluvastatin, pitavastatin and pravastatin) that were used during transdermal drug delivery. The method proved to be most ... -
Optimised transdermal delivery of pravastatin
Burger, Cornel; Gerber, Minja; Du Preez, Jan L.; Du Plessis, Jeanetta (Elsevier, 2015)Wiechers’ programme “Formulating for Efficacy” initiated a new strategy to optimise the oil phase of topical formulations in order to achieve optimal transdermal drug delivery. This new approach uses the “Delivery Gap ... -
Physical stability and clinical efficacy of Crocodylus niloticus oil lotion
Venter, Telanie; Fox, Lizelle Trifena; Gerber, Minja; Du Preez, Jan L.; Van Zyl, Sterna; Boneschans, Banie; Du Plessis, Jeanetta (Elsevier, 2016)The stability and the anti-ageing, skin hydrating and anti-erythema effects of a commercialized Crocodylus niloticus oil lotion was determined. The lotion was stored at controlled conditions over six months during which ... -
Polycyclic cage structures as carrier molecules for neuroprotective non-steroidal anti-inflammatory drugs
Du Preez, Jan L.; Van Dyk, Sandra; Malan, Sarel F. (Elsevier, 2009)The blood-brain barrier is formed by the brain capillary endothelium and plays the predominant role in controlling the passage of substances between the blood and the brain. Recent studies on polycyclic structures, i.e. ... -
Rosuvastatin is transferred into human breast milk: a case report
Schutte, Aletta E.; Du Preez, Jan L.; Symington, Elizabeth A. (Elsevier, 2013)Controversy exists on whether lactating women with familial hypercholesterolemia should resume statin treatment. This is partly due to the unavailability of data in humans regarding the transfer of statins into breast ... -
Skin permeation enhancement effects of the gel and whole 1 leaf materials of A. vera, A. marlothii and A. ferox
Fox, Lizelle T.; Gerber, Minja; Du Preez, Jan L.; Du Plessis, Jeanetta; Hamman, Josias H. (Wiley, 2015)Objectives: The aim of this study was to investigate the in vitro permeation enhancement effects of the gel and whole leaf materials of Aloe vera, Aloe marlothii and Aloe ferox using ketoprofen as a marker compound. Methods: ... -
Social isolation rearing in rats alters plasma tryptophan metabolism and is reversed by sub-chronic clozapine treatment
Möller, Marisa; Du Preez, Jan L.; Harvey, Brian H.; Emsley, Robin (Elsevier, 2012)Schizophrenia is associated with increased oxidative stress, although the source of this redox disequilibrium requires further study. Altered tryptophan metabolism has been described in schizophrenia, possibly linked to ... -
Social isolation rearing induces mitochondrial, immunological, neurochemical and behavioural deficits in rats, and is reversed by clozapine or N-acetyl cysteine
Möller, Marisa; Du Preez, Jan L.; Viljoen, Francois P.; Harvey, Brian H.; Berk, Michael; Emsley, Robin (Elsevier, 2013)Apart from altered dopamine (DA) function, schizophrenia displays mitochondrial and immune-inflammatory abnormalities, evidenced by oxidative stress, altered kynure nine metaboli sm and cytokine release . N-acetyl cysteine ... -
Stability, clinical efficacy and antioxidant properties of honeybush extracts in semi-solid formulations.
Gerber, Gezina S.F.W.; Fox, Lizelle T.; Gerber, Minja; Du Preez, Jan L.; Van Zyl, Sterna; Boneschans, Banie; Du Plessis, Jeanetta (Medknow Publications, 2015)Background: Honeybush extracts (Cyclopia spp.) can be incorporated into skin care products to treat conditions such as skin dryness and can function as an anti-oxidant. Objective: To formulate Honeybush formulations and ... -
Synthesis and transdermal permeation of novel N4-methoxypoly(ethylene glycol) carbamates of cytarabine
Legoabe, Lesetja J.; N'Da, David D.; Breytenbach, Jaco C.; Du Preez, Jan L.; Du Plessis, Jeanetta (Taylor & Francis, 2010)Background: Cytarabine is a deoxycytidine analogue commonly used in the treatment of hematological malignant diseases. Its clinical utility, however, is severely limited by its short plasma half-life because of the catabolic ...