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1.
Cureus ; 14(5): e24969, 2022 May.
Article in English | MEDLINE | ID: mdl-35698676

ABSTRACT

Background The sudden and quick propagation of coronavirus-19 disease (COVID-19) has disrupted face-to-face lectures and practical sessions at Iraqi universities. E-learning has surfaced in most countries as an alternative way to continue educational programs. This study aimed to determine the degree of satisfaction and perceived barriers among college students with E-learning. Methods Students of two Iraqi universities studying through an online platform participated in this cross-sectional study. An online survey questionnaire was used to assess student perceptions of the level of satisfaction with and barriers to E-learning. Participants' non-identifying demographics were also collected. Results The majority of students (70.9%) were females, and more than half (57.9%) were from the Faculty of Science. About 64.8% of the students were not satisfied with the E-learning experience. Only 35.5% of the students attended synchronous electronic classes while the rest used asynchronous learning activities. Students' level of satisfaction was poor, as only 6.4% of students strongly believed that tutoring was informative and that technology and educational technology were adequate. On the contrary, 69% of students strongly agreed that E-learning saved them time and money. Barriers that were perceived by the student were slow internet speed, power interruption, and the lack of face-to-face interaction. Conclusions E-learning has significant barriers that require investment in infrastructures and teaching skills development to make students learning satisfactory.

2.
Alcohol Clin Exp Res ; 44(10): 1997-2007, 2020 10.
Article in English | MEDLINE | ID: mdl-32780433

ABSTRACT

BACKGROUND: Alcohol (EtOH) is reported to adversely affect one of the most crucial roles of the blood-brain barrier (BBB), the regulation of its permeability, thereby compromising the stability of the homeostatic environment of the brain. The central component of the BBB, endothelial cells (ECs), regulates BBB transcellular transport, while their paracellular pathways are made virtually impermeable by molecular structures called tight junctions (TJs). These TJs are composed of proteins, such as claudin-5, a protein involved in the regulation of paracellular permeability and of key interest in this study. METHODS AND RESULTS: The working hypothesis of this study postulated that the high levels of antioxidants (AOs) in the fermented Aspalathus linearis (Rooibos; Rf) tincture may protect the ECs of the BBB against oxidative stress induced by EtOH exposure. Cells were exposed for 24 hours to selected concentrations of EtOH (25 and 100 mM), Rf (containing an antioxidant equivalence of 1.9 nM Aspalathin), and cotreatments of EtOH and Rf. Cell viability, live cell number, and toxicity were analyzed using the trypan blue exclusion assay. RT-qPCR was implemented to quantify claudin-5 transcription. In addition, permeability (Transepithelial Electrical Resistance) of bEnd5 monolayers was measured. The experimental timeline for the above-mentioned parameters was 24 and 48 hours. CONCLUSIONS: Our study showed that simultaneous exposure of Rf and EtOH was able to negate the effects of EtOH on cell viability and cell proliferation, but was not able to reverse or reduce the effects of EtOH on claudin-5 transcription and paracellular permeability. Furthermore, a novel finding in this study suggests that very low concentrations of AOs in tinctures such as Rooibos tea could profoundly alter the redox status of brain ECs.


Subject(s)
Antioxidants/pharmacology , Blood-Brain Barrier/drug effects , Epithelial Cells/drug effects , Ethanol/pharmacology , Neuroprotective Agents/pharmacology , Animals , Antioxidants/metabolism , Cell Line , Cell Membrane Permeability/drug effects , Chalcones/pharmacology , Claudin-5/metabolism , Dose-Response Relationship, Drug , Mice , Oxidative Stress/drug effects , Tight Junctions/drug effects , Transcriptome/drug effects
3.
Metab Brain Dis ; 34(5): 1467-1472, 2019 10.
Article in English | MEDLINE | ID: mdl-31230217

ABSTRACT

Nonketotic hyperglycinemia (NKH) is a neuro-metabolic disorder caused by a deficiency in the glycine cleavage system (GCS) and glycine transporter 1 (GlyT1). A case of atypical late onset of NKH has been reported in a colony of captive-bred Vervet monkeys. The purpose of this study was to evaluate the effect of sodium benzoate and dextromethorphan in reducing glycine levels in hyperglycinemic monkeys. Twelve captive-bred Vervet monkeys were assigned into three groups consisting of four animals (control, valproate induced and cataract with spontaneous hyperglycinemia). Valproate was used to elevate glycine levels and the induced group was then treated with sodium benzoate and dextromethorphan together with group three to normalise glycine levels in cerebrospinal fluid (CSF) and plasma. Valproate induction elicited changes in phosphate, alkaline phosphatase and platelet count, however, no significant changes in the glycine levels were observed, and this might be due to the individual variability within the group. The treatment intervention was only obtained in the spontaneous group whereby the glycine levels were normalised in CSF and plasma. Therefore, it can be concluded that sodium benzoate and dextromethorphan treatment was effective and beneficial to the hyperglycinemic group.


Subject(s)
Dextromethorphan/therapeutic use , Glycine/blood , Hyperglycinemia, Nonketotic/drug therapy , Sodium Benzoate/therapeutic use , Animals , Chlorocebus aethiops , Hyperglycinemia, Nonketotic/blood , Treatment Outcome
4.
Int J Oncol ; 53(6): 2745-2757, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30320392

ABSTRACT

Breast cancer is the most common and the leading cause of female mortality among South African (SA) women. Several non­biological and biological risk factors may be attributed to their observed high mortality rate; however, the molecular profiles associated with their breast tumors are poorly characterized. The present study examined the patterns of genome-wide copy number alterations (CNAs) and their potential impact on functional cellular pathways targeted by cancer driver genes in patients with breast cancer from the Western Cape region of SA. Array-comparative genomic hybridization analysis, performed in 28 cases of invasive breast cancer, revealed a mean number of 8.68±6.18 CNAs per case, affecting primarily the Xp22.3 and 6p21-p25 cytobands (57.14% of the cases), followed by 19p13.3-p13.11 (35.7%), 2p25.3-p24.3, 4p16.3-p15.3, 8q11.1-q24.3 and 16 p13.3-p11.2 (32.14%). Functional enrichment analysis of genes and microRNA targets mapped in these affected cytobands revealed critical cancer-associated pathways, including fatty acid biosynthesis and metabolism, extracellular matrix-receptor interaction, hippo and tumor protein p53 signaling pathways, which are regulated by known cancer genes, including CCND1, CDKN1A, MAPK1, MDM2, TP53 and SMAD2. An inverse correlation was observed among the number of CNAs and tumor size and grade; CNAs on the 4p and 6p cytobands were also inversely correlated with tumor grade. No association was observed in the number of CNAs and/or the affected cytobands and the different ethnic groups of the SA patients, indicating that their tumor genome is affected by CNAs, irrespectively of their genetic descent. Additional genomic tumor profiling in SA and other Sub-Saharan African patients with breast cancer is required to determine the associations of the CNAs observed with prognosis and clinical outcome.


Subject(s)
Breast Neoplasms/pathology , Chromosome Mapping/methods , Comparative Genomic Hybridization/methods , DNA Copy Number Variations , Adult , Aged , Aged, 80 and over , Breast Neoplasms/ethnology , Breast Neoplasms/genetics , Chromosomes, Human, Pair 16/genetics , Chromosomes, Human, Pair 19/genetics , Chromosomes, Human, Pair 2/genetics , Chromosomes, Human, Pair 4/genetics , Chromosomes, Human, Pair 6/genetics , Chromosomes, Human, Pair 8/genetics , Chromosomes, Human, X/genetics , Female , Gene Regulatory Networks , Humans , Middle Aged , Neoplasm Grading , South Africa/ethnology , Young Adult
5.
J Med Primatol ; 47(2): 93-100, 2018 04.
Article in English | MEDLINE | ID: mdl-29377145

ABSTRACT

BACKGROUND: The aim of the study was to evaluate the genetic predisposition of congenital cataract in a colony of captive-bred vervet monkeys. METHODS: Four congenital cataract genes: glucosaminyl (N-acetyl) transferase 2 (GCNT2), heat shock transcription factor 4 (HSF4), crystallin alpha A (CRYAA) and lens intrinsic membrane protein-2 (LIM2) were screened, sequenced and analysed for possible genetic variants in 36 monkeys. Gene expression was also evaluated in these genes. RESULTS: Fifteen sequence variants were identified in the coding regions of three genes (GCNT2, HSF4 and CRYAA). Of these variations, only three were missense mutations (M258V, V16I and S24N) and identified in the GCNT2 transcripts A, B and C, respectively, which resulted in a downregulated gene expression. CONCLUSION: Although the three missense mutations in GCNT2 have a benign effect, a possibility exists that the candidate genes (GCNT2, HSF4 and CRYAA) might harbour mutations that are responsible for total congenital cataract.


Subject(s)
Cataract/congenital , Chlorocebus aethiops , Gene Expression Regulation , Genetic Diseases, X-Linked/genetics , Genetic Diseases, X-Linked/veterinary , Microphthalmos/genetics , Microphthalmos/veterinary , Monkey Diseases/genetics , Animals , Animals, Laboratory , Cataract/genetics , Cataract/veterinary , Female , Male , Monkey Diseases/congenital , Mutation, Missense/genetics
6.
Cytogenet Genome Res ; 146(3): 195-203, 2015.
Article in English | MEDLINE | ID: mdl-26524685

ABSTRACT

Breast cancer is one of the main causes of cancer death among South African women. Although several risk factors can be attributed to the observed high mortality rate, the biology of the tumors is not extensively investigated. Copy number gain of the DLX4 homeobox gene has been observed in breast cancer in association with poor prognosis and specific racial groups. Therefore, we aimed to assess the copy number and prognostic role of DLX4 in breast cancer from South African patients. Due to the co-location of ERBB2 and DLX4 in the 17q21 region, its copy number was also evaluated. Our results in the analysis of 66 cases demonstrated copy number gains of DLX4 and ERBB2 in 24.1 and 29.7% of the cases, respectively. Linear regression analysis showed no dependency between the copy number alterations in these genes. Although not significant, patients with DLX4 and ERBB2 gains presented a higher frequency of advanced-grade tumors. In addition, copy number alterations of these genes were not significantly differently observed in the 3 main racial groups of the Western Cape population: Colored, White, and Black. These findings indicate that gains of DLX4 and ERBB2 occur in South African breast cancer patients irrespectively of their race and factors known to influence prognosis.


Subject(s)
Breast Neoplasms/genetics , DNA Copy Number Variations , Genes, erbB-2 , Homeodomain Proteins/genetics , Transcription Factors/genetics , Adult , Aged , Breast Neoplasms/ethnology , Female , Humans , Middle Aged , Retrospective Studies , South Africa
7.
Open Virol J ; 4: 76-84, 2010 May 25.
Article in English | MEDLINE | ID: mdl-20700397

ABSTRACT

Even though coronavirus infection of humans is not normally associated with severe diseases, the identification of the coronavirus responsible for the outbreak of severe acute respiratory syndrome showed that highly pathogenic coronaviruses can enter the human population. Shortly thereafter, in Holland in 2004, another novel human coronavirus (HCoV-NL63) was isolated from a seven-month old infant suffering from respiratory symptoms. This virus has subsequently been identified in various countries, indicating a worldwide distribution. HCoV-NL63 has been shown to infect mainly children and the immunocommpromised, who presented with either mild upper respiratory symptoms (cough, fever and rhinorrhoea) or more serious lower respiratory tract involvement such as bronchiolitis and croup, which was observed mainly in younger children. In fact, HCoV-NL63 is the aetiological agent for up to 10% of all respiratory diseases. This review summarizes recent findings of human coronavirus HCoV-NL63 infections, including isolation and identification, phylogeny and taxonomy, genome structure and transcriptional regulation, transmission and pathogenesis, and detection and diagnosis.

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