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"Hamdan, Abdullah M"
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Coronal discoloration induced by calcium silicate-based cements used in full pulpotomy in mature permanent molars: a randomized clinical trial
by
Al-Hiyasat, Ahmad S
,
Taha, Nessrin A
,
Hamdan, Abdullah M
in
Clinical trials
,
Hemostasis
,
Molars
2023
ObjectivesThis study aimed to randomly compare in vivo coronal discoloration at 6 and 12 months after full pulpotomy in mature permanent molars using MTA, Biodentine, and TotalFill and to investigate the effect of variables such as remaining buccal wall thickness and time to achieve hemostasis.Materials and methodsOne hundred eight teeth that met the inclusion criteria received full pulpotomy and were randomly divided into 3 groups via a block randomization technique according to the calcium silicate cement (CSC): ProRoot WMTA, TotalFill, or Biodentine. Assessment of tooth color was carried out using a spectrophotometric device (VITA Easyshade Compact) after composite placement (T0), at 6- and 12-month follow-up. Buccal wall thickness and time to hemostasis were recorded. The primary outcome measure (color change ΔE) was calculated, and the results were analyzed by three-way ANOVA and crosstabulations in relation to material type and effect of variables.ResultsFour cases were excluded after pulpotomy failure; 81 teeth were evaluated at 6 months and 95 teeth at 12 months. All CSCs caused tooth discoloration (defined as ΔE > 3.7); MTA significantly caused the highest color change at 6- and 12-month follow-up (76% (19/25) and 87.5% (28/32), respectively) compared to Biodentine (41% (9/22), 48% (13/27)) and TotalFill (44% (15/34), 53% (19/53)) (p = 0.022, p = 0.002), while no significant difference was found between the Biodentine and TotalFill groups (p = 0.813, p = 0.8). Buccal wall thickness (above or below 2.7 mm) had a significant effect on the degree of discoloration (p = 0.004).ConclusionsThe 3 CSCs caused tooth discoloration based on the threshold of ΔE > 3; the remaining buccal wall thickness was a significant factor. The use of Biodentine and TotalFill instead of MTA is encouraged to minimize discoloration.Clinical relevanceWhile experimental studies report coronal discoloration after CSCs use, clinical data is lacking. This study assessed discoloration using a spectrophotometric device. The use of materials with lower discoloration potential in pulpotomy is encouraged.Trial registrationThe study was registered with clinical trial registration number: NCT04346849 on 14.4.2020.
Journal Article
A classroom observational study of Qatar's independent schools: Instruction and school reform
by
Viruru, Radhika
,
Rollins, Kayla
,
Stillisano, Jacqueline
in
Classroom management
,
Classroom observation
,
Cohort Analysis
2016
Qatar initiated a K-12 national educational reform in 2001. However, there is limited information on the instructional practices of the teachers in the reform schools. This project was an observational study of classrooms with a stratified random sample of the first six cohorts of reform schools. Specifically, 156 classrooms were observed in 29 reform schools. Instructional differences were noted in schools with different gender of students and were moderated by school level. Implications of findings were discussed pertaining to implementation of the Qatar national reform and professional development needs of teachers.
Journal Article
Antibacterial activity of trimetal (CuZnFe) oxide nanoparticles
by
Niazy, Abdurahman
,
Alghamdi, Hamdan
,
Wahab, Rizwan
in
Anti-Bacterial Agents - chemistry
,
Anti-Bacterial Agents - pharmacology
,
Antibacterial agents
2018
The increasing resistance of pathogenic bacteria to antibiotics is a challenging worldwide health problem that has led to the search for new and more efficient antibacterial agents. Nanotechnology has proven to be an effective tool for the fight against bacteria.
In this paper, we present the synthesis and traits of trimetal (CuZnFe) oxide nanoparticles (NPs) using X-ray diffraction, high-resolution transmission electron microscopy, and energy dispersive x-ray spectroscopy. We evaluated the antibacterial activity of these NPs against gram-negative
and gram-positive
and then compared it to that of their pure single-metal oxide components CuO and ZnO.
Our study showed that the antibacterial activity of the trimetal oxide NPs was greater against
.
than against
.
. Overall, the antimicrobial effect of trimetal NPs is between those of pure ZnO and CuO nanoparticles, which may mean that their cytotoxicity is also between that of pure ZnO and CuO NPs, making them potential antibiotics. However, the cytotoxicity of trimetal NPs to mammalian cells needs to be verified.
The combination of three metal oxide NPs (ZnO, CuO, and Fe
O
) in one multimetal (CuZnFe) oxide NPs will enhance the therapeutic strategy against a wide range of microbial infections. Bacteria are unlikely to develop resistance against this new NP because bacteria must go through a series of mutations to become resistant to the trimetal oxide NP. Therefore, this NP can combat existing and emerging bacterial infections.
Journal Article
Epidemiological Characteristics, Pathogenesis and Clinical Implications of Sinusitis in the Era of COVID-19: A Narrative Review
by
Muharib R Alruwaili, Khalid
,
N Al‐Rasheedi, Abdullah
,
Fahid ALtimani, Abdullah
in
and fungal rhinosinusitis
,
Cancer
,
Chemotherapy
2023
Sinusitis is a common condition with various forms and different etiologies. In the era of COVID-19, a large number of studies covered the association between sinusitis and COVID-19, while others reported the impact of COVID-19 on the development of acute invasive fungal rhinosinusitis (AIFR), together with the most commonly associated predisposing factors. Fungal sinusitis, particularly AIFR, can be life-threatening. It is important to dissect this association and improve current evidence and management. Therefore, we conducted this literature review to highlight the association between COVID-19 and sinusitis based on evidence from the available studies in the literature. Evidence shows that chronic sinusitis might have a negative impact on COVID-19 outcomes. However, current results are conflicting, and further studies are needed. On the other hand, COVID-19 can also cause olfactory dysfunction, which is usually temporary. In addition, we found several studies that indicated the association between COVID-19 and AIFR. The condition is usually associated with severe morbidities, as affected patients are usually immunocompromised, including those with uncontrolled diabetes, malignancy, immunosuppression, AIDS, the administration of chemotherapy and other immunosuppressive drugs, and COVID-19.
Journal Article
The prevalence of sleep disturbance among asthmatic patients in a tertiary care center
by
AL-Jahdali, Hamdan
,
Alghamdi, Hazim S.
,
Alkewaibeen, Abdulaziz M.
in
692/1807
,
692/499
,
692/617/375/1816
2021
Sleep disturbances are commonly reported by patients with asthma. However, the prevalence of sleep disturbance and its association with the level of asthma control is unknown. The primary objective was to determine the prevalence of sleep disturbance among Saudi adult asthmatic patients attending pulmonary clinics at King Abdulaziz Medical City (KAMC). The study also aimed to compare sleep quality between controlled and uncontrolled asthma patients. The study was carried out in the outpatient pulmonary clinics at KAMC and utilized a cross-sectional survey. The survey included five different questionnaires: asthma control test and questionnaires related to the quality of sleep (Pittsburgh sleep quality index [PSQI], Epworth sleepiness scale [ESS], Berlin questionnaire [a measure of obstructive sleep apnea risk], and insomnia severity index [ISI]). Among the 200 asthma patients, 66% suffered from poor sleep quality (PSQI > 5), 43% were at high risk for obstructive sleep apnea, 25% had excessive daytime sleepiness (ESS > 10), and 46.5% had significant clinical insomnia (ISI ≥ 10). Poor sleep quality was less common in patients with well-controlled asthma (37%) compared to those with partially controlled asthma (78%) and uncontrolled asthma (82%) (p < 0.001). Poor sleep quality was common among patients with asthma, particularly those with suboptimal levels of asthma control. Further studies are needed to better understand the interaction between these two conditions.
Journal Article
Antigen Unmasking Is Required to Clinically Assess Levels and Localisation Patterns of Phospholipase C Zeta in Human Sperm
by
Abu-Dawud, Raed
,
Hamdan, Hamdan
,
Almuqayyil, Sarah
in
Antibodies
,
antigen retrieval/unmasking
,
Antigens
2023
Mammalian oocyte activation is initiated by intracellular calcium (Ca2+) oscillations, driven by the testis-specific phospholipase C zeta (PLCζ). Sperm PLCζ analysis represents a diagnostic measure of sperm fertilisation capacity. The application of antigen unmasking/retrieval (AUM) generally enhanced the visualisation efficacy of PLCζ in mammalian sperm, but differentially affected the PLCζ profiles in sperm from different human males. It is unclear whether AUM affects the diagnosis of PLCζ in human sperm. Herein, we examined whether the application of AUM affected the correlation of PLCζ profiles with sperm parameters and fertilisation capacity. PLCζ fluorescence levels and localisation patterns were examined within the sperm of males undergoing fertility treatment (55 patients aged 29–53) using immunofluorescence in the absence/presence of AUM. The changes in PLCζ profiles following AUM were examined in relation to sperm health and fertilisation outcome. AUM enhanced the observable levels and specific localisation patterns of PLCζ in relation to both optimal sperm parameters and fertilisation outcome, without which significant differences were not observed. The extent of the change in levels and localisation ratios of PLCζ was also affected to a larger degree in terms of the optimal parameters of sperm fertility and fertilisation capacity by AUM. Collectively, AUM was essential to accurately assesses PLCζ in human sperm in both scientific and clinical contexts.
Journal Article
Gas Flow Blockage Treatment in Shale Gas: Case Study of Qusaiba Hot Shale, Saudi Arabia
by
AlQuraishi, Abdulrahman A.
,
AlMansour, Abdullah O.
,
AlYami, Hamdan Q.
in
Analysis
,
capillary pressure
,
Contact angle
2024
Organic-rich hot Qusaiba shale is the primary source rock of most of the Paleozoic hydrocarbon reservoirs of eastern and central Arabia. Representative near-surface Qusaiba shale samples were collected and characterized from one of its outcrop sections at the Tayma quadrangle in northwest Saudi Arabia. The petrophysical and geochemical characterization indicated porosity and permeability of 8.2% and 2.05 nD, respectively, with good total organic carbon (TOC) of 2.2 mg/g and mature kerogen of gas-prone type III. The tight characteristics of the formation can lead to high capillary pressure and extensive post-fracking water retention, leading to flow blockage and a reduction in gas productivity. Three different surfactants and one ionic liquid, namely, Triton X-100, Triton X-405 and Zonyle FSO surfactants and Ammoeng 102 ionic liquid, were tested as additives to fracking fluid to investigate their effectiveness in optimizing its performance. The chemical solutions exhibited no sign of instability when exposed to solution salinity and temperatures up to 70 °C. The investigated chemicals’ performance was examined by measuring methane/chemical solutions’ surface tension and their ability to alter shale’s wettability. The results indicate that Zonyl FSO is the most effective chemical, as it is able to significantly reduce surface tension and, hence, capillary pressure by 66% when added at critical micelle concentration (CMC). Using Zonyl FSO surfactant at a maximum tested concentration of 0.2% induced a relatively smaller capillary pressure drop (54%) due to the drastic drop in the contact angle rendering shale very strongly water-wet. Such a drop in capillary pressure can lower the fracking fluid invasion depth and therefore ease the liquid blockage removal during the flowback stage, enhancing gas recovery during the extended production stage. Triton X-100 at CMC was the second most effective surfactant and was able to induce a quite significant 47% drop in capillary pressure when added at the maximum tested concentration of 0.05%. This was sufficient to remove any liquid blockage but was less likely to alter the wettability of the shale. Based on the findings obtained, it is suggested to reduce the blockage tendency during the fracking process and elevate any existing blockage during the flowback stage by using Zonyl FSO at CMC where IFT is at its minimum with a higher contact angle.
Journal Article
Dexamethasone–tamoxifen combination exerts synergistic therapeutic effects in tamoxifen-resistance breast cancer cells
by
Almilaibary, Abdullah
,
Gaballah, Aliaa I.
,
Fayyad, Reda Mohamed Abdrabbou
in
Antineoplastic Agents, Hormonal - pharmacology
,
Antineoplastic Combined Chemotherapy Protocols - pharmacology
,
Apoptosis
2024
Tamoxifen (TAM) is a key player in estrogen receptor-positive (ER+) breast cancer (BC); however, ∼30% of patients experience relapse and a lower survival rate due to TAM resistance. TAM resistance was related to the over expression of SOX-2 gene, which is regulated by the E2F3 transcription factor in the Wnt signaling pathway. It was suggested that SOX-2 overexpression was suppressed by dexamethasone (DEX), a glucocorticoid commonly prescribed to BC patients. The aim of the present study is to explore the effect of combining DEX and TAM on the inhibition of TAM-resistant LCC-2 cells (TAMR-1) through modulating the E2F3/SOX-2-mediated Wnt signaling pathway. The effect of the combination therapy on MCF-7 and TAMR-1 cell viability was assessed. Drug interactions were analyzed using CompuSyn and SynergyFinder softwares. Cell cycle distribution, apoptotic protein expression, gene expression levels of SOX-2 and E2F3, and cell migration were also assessed. Combining DEX with TAM led to synergistic inhibition of TAMR-1 cell proliferation and migration, induced apoptosis, reduced SOX-2 and E2F3 expression and was also associated with S and G2-M phase arrest. Therefore, combining DEX with TAM may present an effective therapeutic option to overcome TAM resistance, by targeting the E2F3/SOX-2/Wnt signaling pathway, in addition to its anti-inflammatory effect.
Journal Article
Medication Adherence to Semaglutide Once-Weekly Injection Among Type-2 Diabetes Patients in Tabuk, Saudi Arabia – A Cross-Sectional Study
by
A Albrahimi, Hazem Moufeed
,
Alatawi, Ahmed
,
Aljabri, Ahmed
in
adherence to refills and medications scale
,
Agonists
,
Analysis
2025
Semaglutide, a once-weekly injection (SOWI), is a glucagon-like peptide-1 receptor agonist for managing type-2 diabetes (T2D). However, it has a high discontinuation rate among users in the first year after treatment initiation. This study investigated the medication adherence level among T2D patients managed with SOWI.
This cross-sectional study was conducted among T2D patients aged 18 years or above who visited the outpatient pharmacy to refill their prescriptions for SOWI. The patients responded to their sociodemographic characteristics and the Adherence to Refills and Medications Scale (ARMS). The patient's electronic health record obtained details of the proportion of days covered (PDC), glycosylated hemoglobin (HbA1C), and body mass index (BMI). The association of medication adherence and sociodemographic characteristics, as well as the clinical outcomes between patients with different levels of adherence, were analyzed.
A total of 434 patients were included in this study. According to the ARMS score, only 32.48% (141) of the patients adhered to SOWI. Sociodemographic characteristics had lower odds association for medication non-adherence. However, non-adherent patients had a significant association with BMI (overweight and obese) and HbA1C (>7). The adherence level of PDC for SOWI was significantly associated with the ARMS medication adherence level. The mean HbA1C and BMI between adherents and non-adherents were statistically significant (p<0.001). The patients who adhered to both ARMS and PDC (n = 126) experienced a significant decline in mean BMI (p < 0.001) and HbA1C (p < 0.001) compared to patients who adhered to PDC but not ARMS and those who did not adhere to either ARMS or PDC.
Medication adherence to the SOWI is subjective to T2D patients and not influenced by sociodemographic characteristics. T2D patients need more motivation to refill and administer the SOWI according to the schedule since medication adherence directly impacts HbA1C and BMI.
Journal Article
The potential benefit of an educational intervention on needle stick injury prevention among dental students at the university of Ha’il, Saudi Arabia: a prospective study
by
Madfa, Ahmed A.
,
Alotaibi, Abeer S.
,
Alshammari, Hamdan A.
in
Adult
,
Attitudes
,
Best Practices
2025
Background
Needle stick injuries (NSIs) pose a significant occupational hazard to healthcare professionals, including dental students. Despite the availability of guidelines and preventive strategies, knowledge, training, and compliance remain inadequate among dental students. Therefore, this study aimed to evaluate the Prospective gain of an educational pack in reducing NSIs and improving knowledge of attitudes towards, and compliance with NSI prevention and management guidelines among dental students.
Methods
A prospective audit design was employed over four weeks, involving fourth-, fifth-, and sixth-year dental students. The study consisted of three phases: pre-assessment, educational intervention, and post-assessment. Baseline knowledge, attitudes, and practices were evaluated using a structured questionnaire. Self-reported compliance with safe sharps handling practices has been designated as the primary outcome. The educational pack, comprising presentations, comparative data, interactive scenarios, and guidelines, was delivered during the intervention phase. Post-intervention assessments used the same questionnaire to measure changes in outcomes. Data were analysed using SPSS, and statistical significance was set at
p
≤ 0.05.
Results
Post-intervention, the incidence of NSIs significantly decreased, with self-reported cases reducing from 17.2% to 4.3%. Knowledge scores improved markedly, with the percentage of correct answers to key questions rising from 34.5% to 93.1% among sixth-year students (
p
= 0.032). Gender-based analysis revealed statistically significant improvements in scores for both male and female students, with female students achieving higher post-assessment scores for key questions (e.g. 93.8% vs 75.6%,
p
= 0.014). Students with lower GPAs demonstrated the greatest improvement, with scores increasing from 14.3% to 100% in some areas (
p
= 0.022).
Conclusion
The findings underscore the change following the intervention of structured infection control training in reducing NSIs and improving adherence to guidelines. Integrating such programs into dental curricula is vital for fostering a culture of safety and compliance in clinical practice. This study aligns with Saudi Vision 2030, emphasising the importance of enhancing healthcare quality and occupational safety through targeted educational interventions.
Journal Article