Turki S. Abujamel

Dr. Turki S. Abujamel


Research Focus & Metrics

Academic Career Length

7Years (2020-Present)

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

Representative Publications

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5 August 2021 in Brain Sciences
Verified
Journal Article
Open access
PDF file
SASameera Abuaish
Sameera Abuaish
NANorah M. Alotaibi
Norah M. Alotaibi
TATurki S. Abujamel
Turki S. Abujamel
SASaleha Ahmad Alzahrani
Saleha Ahmad Alzahrani
SASohailah Masoud Alotaibi
Sohailah Masoud Alotaibi
Afaf El-AnsaryAfaf El-Ansary
Afaf El-Ansary
Autism is associated with gastrointestinal dysfunction and gut microbiota dysbiosis, including an overall increase in Clostridium. Modulation of the gut microbiota is suggested to improve autistic symptoms. In this study, we explored the implementation of two different interventions that target the microbiota in a rodent model of autism and their effects on social behavior: the levels of different fecal Clostridium spp., and hippocampal transcript levels. Autism was induced in young Sprague Dawley male rats using oral gavage of propionic acid (PPA) for three days, while controls received saline. PPA-treated animals were divided to receive either saline, fecal transplant from healthy donor rats, or Bifidobacterium for 22 days, while controls continued to receive saline. We found that PPA attenuated social interaction in animals, which was rescued by the two interventions. PPA-treated animals had a significantly increased abundance of fecal C. perfringens with a concomitant decrease in Clostridium cluster IV, and exhibited high hippocampal Bdnf expression compared to controls. Fecal microbiota transplantation or Bifidobacterium treatment restored the balance of fecal Clostridium spp. and normalized the level of Bdnf expression. These findings highlight the involvement of the gut–brain axis in the etiology of autism and propose possible interventions in a preclinical model of autism.

4 December 2020 in Viruses
Verified
Journal Article
Open access
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AHAnwar Hashem
Anwar Hashem
AAAbdullah Algaissi
Abdullah Algaissi
SASarah Almahboub
Sarah Almahboub
MAMohamed Alfaleh
Mohamed Alfaleh
TATurki S. Abujamel
Turki S. Abujamel
Xuguang LiXuguang Li
Xuguang Li
The Coronavirus Disease 2019 (COVID-19), caused by SARS-CoV-2, continues to spread globally with significantly high morbidity and mortality rates. Antigen-specific responses are of unquestionable value for clinical management of COVID-19 patients. Here, we investigated the kinetics of IgM, IgG against the spike (S) and nucleoproteins (N) proteins and their neutralizing capabilities in hospitalized COVID-19 patients with different disease presentations (i.e., mild, moderate or severe), need for intensive care units (ICU) admission or outcomes (i.e., survival vs death). We show that SARS-CoV-2 specific IgG, IgM and neutralizing antibodies (nAbs) were readily detectable in almost all COVID-19 patients with various clinical presentations. Interestingly, significantly higher levels of nAbs as well as anti-S1 and -N IgG and IgM antibodies were found in patients with more severe symptoms, patients requiring admission to ICU or those with fatal outcomes. More importantly, early after symptoms onset, we found that the levels of anti-N antibodies correlated strongly with disease severity. Collectively, these findings provide new insights into the kinetics of antibody responses in COVID-19 patients with different disease severity.

7 April 2021 in Molecules
Verified
Journal Article
Open access
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EAEnas Mahmoud Amer
Enas Mahmoud Amer
SKSaber Abd El kader
Saber Abd El kader
Ahmad Abo MarkebAhmad Abo Markeb
Ahmad Abo Markeb
AEAmal A. Elkhawaga
Amal A. Elkhawaga
IMIslam Mekhemer
Islam Mekhemer
EAElham Abd Allah
Elham Abd Allah
Beta glucan (β-glucan) has promising bioactive properties. Consequently, the use of β-glucan as a food additive is favored with the dual-purpose potential of increasing the fiber content of food products and enhancing their health properties. Our aim was to evaluate the biological activity of β-glucan (antimicrobial, antitoxic, immunostimulatory, and anticancer) extracted from Saccharomyces cerevisiae using a modified acid-base extraction method. The results demonstrated that a modified acid-base extraction method gives a higher biological efficacy of β-glucan than in the water extraction method. Using 0.5 mg dry weight of acid-base extracted β-glucan (AB extracted) not only succeeded in removing 100% of aflatoxins, but also had a promising antimicrobial activity against multidrug-resistant bacteria, fungi, and yeast, with minimum inhibitory concentrations (MIC) of 0.39 and 0.19 mg/mL in the case of resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, respectively. In addition, AB extract exhibited a positive immunomodulatory effect, mediated through the high induction of TNFα, IL-6, IFN-γ, and IL-2. Moreover, AB extract showed a greater anticancer effect against A549, MDA-MB-232, and HepG-2 cells compared to WI-38 cells, at high concentrations. By studying the cell death mechanism using flow-cytometry, AB extract was shown to induce apoptotic cell death at higher concentrations, as in the case of MDA-MB-231 and HePG-2 cells. In conclusion, the use of a modified AB for β-glucan from Saccharomyces cerevisiae exerted a promising antimicrobial, immunomodulatory efficacy, and anti-cancer potential. Future research should focus on evaluating β-glucan in various biological systems and elucidating the underlying mechanism of action.

30 January 2022 in Nutrients
Verified
Journal Article
Open access
PDF file
TATurki S. Abujamel
Turki S. Abujamel
NANorah M. Alotaibi
Norah M. Alotaibi
SASameera Abuaish
Sameera Abuaish
RARahaf AlHarbi
Rahaf AlHarbi
BABakri M. Assas
Bakri M. Assas
Kawther AabedKawther Aabed
Kawther Aabed
Autism spectrum disorders (ASD) consist of a range of neurodevelopmental conditions accompanied by dysbiosis of gut microbiota. Therefore, a number of microbiota manipulation strategies were developed to restore their balance. However, a comprehensive comparison of the various methods on gut microbiota is still lacking. Here, we evaluated the effect of Bifidobacterium (BF) treatment and fecal microbiota transplantation (FT) on gut microbiota in a propionic acid (PPA) rat model of autism using 16S rRNA sequencing. Following PPA treatment, gut microbiota showed depletion of Bacteroidia and Akkermansia accompanied by a concomitant increase of Streptococcus, Lachnospiraceae, and Paraeggerthella. The dysbiosis was predicted to cause increased levels of porphyrin metabolism and impairments of acyl-CoA thioesterase and ubiquinone biosynthesis. On the contrary, BF and FT treatments resulted in a distinct increase of Clostridium, Bifidobacterium, Marvinbryantia, Butyricicoccus, and Dorea. The taxa in BF group positively correlated with vitamin B12 and flagella biosynthesis, while FT mainly enriched flagella biosynthesis. In contrast, BF and FT treatments negatively correlated with succinate biosynthesis, pyruvate metabolism, nitrogen metabolism, beta-Lactam resistance, and peptidoglycan biosynthesis. Therefore, the present study demonstrated that BF and FT treatments restored the PPA-induced dysbiosis in a treatment-specific manner.

30 August 2022 in Polymers
Verified
Journal Article
Open access
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MAMohamed Alfaleh
Mohamed Alfaleh
AHAnwar Hashem
Anwar Hashem
TATurki S. Abujamel
Turki S. Abujamel
NANabil A. Alhakamy
Nabil A. Alhakamy
Mohd Abul KalamMohd Abul Kalam
Mohd Abul Kalam
Shadab MDShadab MD
Shadab MD
Colon cancer (CC) is one of major causes of mortality and affects the socio-economic status world-wide. Therefore, developing a novel and efficient delivery system is needed for CC management. Thus, in the present study, lipid polymer hybrid nanoparticles of apigenin (LPHyNPs) was prepared and characterized on various parameters such as particle size (234.80 ± 12.28 nm), PDI (0.11 ± 0.04), zeta potential (−5.15 ± 0.70 mV), EE (55.18 ± 3.61%), etc. Additionally, the DSC, XRD, and FT-IR analysis determined drug entrapment and affinity with the selected excipient, demonstrating a promising drug affinity with the lipid polymer. Morphological analysis via SEM and TEM exhibited spherical NPs with a dark color core, which indicated drug entrapment inside the core. In vitro release study showed significant (p < 0.05) sustained release of AGN from LPHyNPs than AGN suspension. Further, the therapeutic efficacy in terms of apoptosis and cell cycle arrest of developed LPHyNPs against CC was estimated by performing flow cytometry and comparing its effectiveness with blank LPHyNPs and AGN suspension, which exhibited remarkable outcomes in favor of LPHyNPs. Moreover, the mechanism behind the anticancer attribute was further explored by estimating gene expression of various signaling molecules such as Bcl-2, BAX, NF-κB, and mTOR that were involved in carcinogenic pathways, which indicated significant (p < 0.05) results for LPHyNPs. Moreover, to strengthen the anticancer potential of LPHyNPs against chemoresistance, the expression of JNK and MDR-1 genes was estimated. Outcomes showed that their expression level reduced appreciably when compared to blank LPHyNPs and AGN suspension. Hence, it can be concluded that developed LPHyNPs could be an efficient therapeutic system for managing CC.

27 December 2022 in Journal of Medical Virology
Verified
Journal Article
Open access
MAManar M. Alzahrani
Manar M. Alzahrani
SBShatha Bamashmous
Shatha Bamashmous
HAHanaa Alkharobi
Hanaa Alkharobi
AAAbdullah Alghamdi
Abdullah Alghamdi
RARahaf H. Alharbi
Rahaf H. Alharbi
AHAnwar Hashem
Anwar Hashem
Considering the global trend to confine the COVID‐19 pandemic by applying various preventive health measures, preprocedural mouth rinsing has been proposed to mitigate the transmission risk of SARS‐CoV‐2 in dental clinics. The study aimed to investigate the effect of different mouth rinses on salivary viral load in COVID‐19 patients. This study was a single‐center, randomized, double‐blind, six‐parallel‐group, placebo‐controlled clinical trial that investigated the effect of four mouth rinses (1% povidone‐iodine, 1.5% hydrogen peroxide, 0.075% cetylpyridinium chloride, and 80 ppm hypochlorous acid) on salivary SARS‐CoV‐2 viral load relative to the distilled water and no‐rinse control groups. The viral load was measured by quantitative reverse transcription PCR (RT‐qPCR) at baseline and 5, 30, and 60 min post rinsing. The viral load pattern within each mouth rinse group showed a reduction overtime; however, this reduction was only statistically significant in the hydrogen peroxide group. Further, a significant reduction in the viral load was observed between povidone‐iodine, hydrogen peroxide, and cetylpyridinium chloride compared to the no‐rinse group at 60 min, indicating their late antiviral potential. Interestingly, a similar statistically significant reduction was also observed in the distilled water control group compared to the no‐rinse group at 60 min, proposing mechanical washing of the viral particles through the rinsing procedure. Therefore, results suggest using preprocedural mouth rinses, particularly hydrogen peroxide, as a risk‐mitigation step before dental procedures, along with strict adherence to other infection control measures.