Xavier Siwe Noundou

Prof. Xavier Siwe Noundou

Pharmaceutical Sciences, SEFAKO MAKGATHO HEALTH SCIENCE UNIVERSITY, Pretoria, Gauteng, South Africa
orcid

Research Focus & Metrics

Academic Career Length

20Years (2007-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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15 May 2023 in Environmental Pollution
Verified
Journal Article
Open access
ETEdgar Tumwesigye
Edgar Tumwesigye
CNChika Felicitas Nnadozie
Chika Felicitas Nnadozie
FAFrank C Akamagwuna
Frank C Akamagwuna
XNXavier Siwe Noundou
Xavier Siwe Noundou
GNGeorge William Nyakairu
George William Nyakairu
Oghenekaro Nelson OdumeOghenekaro Nelson Odume
Oghenekaro Nelson Odume
Microplastics (MPs) are becoming ubiquitous, and their environmental fate is becoming an issue of concern. Our review aims to synthesize current knowledge status and provide future perspectives regarding the vector effect of MPs for chemical contaminants and biological agents. The evidence in the literature indicates that MPs are a vector for persistent organic pollutants (POPs), metals and pharmaceuticals. Concentrations of chemical contaminant in orders of six-fold higher on MPs surfaces than in the surrounding environmental waters have been reported. Chemical pollutants such as perfluoroalkyl substances (PAFSs), hexachlorocyclohexane (HCHs) and polycyclic aromatic hydrocarbons (PAHs), exhibiting polarities in the range of 3.3-9 are the commonest chemicals reported on MP surfaces. Regarding metals on MPs including chromium (Cr), lead (Pb), cobalt (Co), the presence of C-O and N-H in MPs promote a relatively high adsorption of these metals onto MP surfaces. Regarding pharmaceuticals, not much has been done, but a few studies indicate that commonly used drugs such as ibuprofen, ibuprofen, diclofenac, and naproxen have been associated with MPs. There is sufficient evidence supporting the claim that MPs can act as vectors for viruses, bacterial and antibiotic-resistant bacteria and genes, and MPs act to accelerate horizontal and vertical gene transfer. An area that deserves urgent attention is whether MPs can act as vectors for invertebrates and vertebrates, mainly non-native, invasive freshwater species. Despite the ecological significance of invasive biology, little research has been done in this regard. Overall, our review summarises the state of the current knowledge, identifies critical research gaps and provides perspectives for future research.

1 March 2019 in International Nano Letters
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Journal Article
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KEKenneth Ezealisiji
Kenneth Ezealisiji
XNXavier Siwe Noundou
Xavier Siwe Noundou
BMBlessing Maduelosi
Blessing Maduelosi
NNNkemakolam Nwachukwu
Nkemakolam Nwachukwu
RKRui Krause
Rui Krause
Current study reports a simple and one-pot synthesis of zinc oxide nanoparticles (ZnONPs) using an aqueous extract of Solanum torvum and evaluation of its toxicological profile (0.5% w/w and 1.0% w/w) in Wistar albino rats with respect to the biochemical index. The nanoparticles were characterized using ultraviolet–visible spectroscopy, transmission electron microscopy, Fourier transform infrared spectroscopy and X-ray diffraction technique. Dynamic light scattering (DLS) and zeta potential of synthesized nanoparticles were analyzed to know the average size and stability of particles. Synthesized nanoparticles were stable, discreet, and mostly spherical, and size of particles was within the nanometre range. Biochemical markers of hepatic and renal functions were measured. Zinc oxide nanoparticles significantly decreased serum uric acid level (p < 0.001) in a dose-dependent manner, while the serum alkaline phosphatase level was increased at the two test doses. The level of alanine transaminase was increased after exposure for 28 days (p < 0.05). This study concludes that biogenic zinc oxide nanoparticles-infused hydrogel applied dermatologically could affect hepatic and renal performance in rats, and there was an observed cumulative toxicological effect with time of exposure.

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Bwalya Angel WitikaBwalya Angel Witika
Bwalya Angel Witika
KBKokoette Bassey
Kokoette Bassey
PDPatrick Demana
Patrick Demana
XNXavier Siwe Noundou
Xavier Siwe Noundou
MADAN POKAMADAN POKA
MADAN POKA
Development of nanomaterials for drug delivery has received considerable attention due to their potential for achieving on-target delivery to the diseased area while the surrounding healthy tissue is spared. Safe and efficiently delivered payloads have always been a challenge in pharmaceutics. Niosomes are self-assembled vesicular nanocarriers formed by hydration of a non-ionic surfactant, cholesterol or other molecules that combine to form a versatile drug delivery system with a variety of applications ranging from topical delivery to targeted delivery. Niosomes have advantages similar to those of liposomes with regards to their ability to incorporate both hydrophilic and hydrophobic payloads. Moreover, niosomes have simple manufacturing methods, low production cost and exhibit extended stability, consequently overcoming the major drawbacks associated with liposomes. This review provides a comprehensive summary of niosomal research to date, including the types of niosomes and critical material attributes (CMA) and critical process parameters (CPP) of niosomes and their effects on the critical quality attributes (CQA) of the technology. Furthermore, physical characterisation techniques of niosomes are provided. The review then highlights recent applications of specialised niosomes in drug delivery. Finally, limitations and prospects for this technology are discussed.

20 June 2023 in Cells
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Journal Article
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TRTithi Roy
Tithi Roy
SBSamuel Boateng
Samuel Boateng
MUMohammad Uddin
Mohammad Uddin
SBSergette Banang-Mbeumi
Sergette Banang-Mbeumi
RYRajesh Kumar Yadav
Rajesh Kumar Yadav
Jean Christopher ChamcheuJean Christopher Chamcheu
Jean Christopher Chamcheu
The dysregulated phosphatidylinositol-3-kinase (PI3K)-Akt-mammalian target of rapamycin (mTOR) signaling pathway has been implicated in various immune-mediated inflammatory and hyperproliferative dermatoses such as acne, atopic dermatitis, alopecia, psoriasis, wounds, and vitiligo, and is associated with poor treatment outcomes. Improved comprehension of the consequences of the dysregulated PI3K/Akt/mTOR pathway in patients with inflammatory dermatoses has resulted in the development of novel therapeutic approaches. Nonetheless, more studies are necessary to validate the regulatory role of this pathway and to create more effective preventive and treatment methods for a wide range of inflammatory skin diseases. Several studies have revealed that certain natural products and synthetic compounds can obstruct the expression/activity of PI3K/Akt/mTOR, underscoring their potential in managing common and persistent skin inflammatory disorders. This review summarizes recent advances in understanding the role of the activated PI3K/Akt/mTOR pathway and associated components in immune-mediated inflammatory dermatoses and discusses the potential of bioactive natural products, synthetic scaffolds, and biologic agents in their prevention and treatment. However, further research is necessary to validate the regulatory role of this pathway and develop more effective therapies for inflammatory skin disorders.

1 February 2017 in Marine Pollution Bulletin
Verified
Journal Article
Closed access
HNHolly Astrid Nel
Holly Astrid Nel
JHJeffrey William Hean
Jeffrey William Hean
XNXavier Siwe Noundou
Xavier Siwe Noundou
William FronemanWilliam Froneman
William Froneman

13 November 2017 in Aquaculture International
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Deyan StratevDeyan Stratev
Deyan Stratev
Georgi ZhelyazkovGeorgi Zhelyazkov
Georgi Zhelyazkov
XNXavier Siwe Noundou
Xavier Siwe Noundou
RKRui Krause
Rui Krause