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51.
52.
Hisham S. M. Abd-Rabboh Abd El-Galil E. Amr Ahmed M. Naglah Abdulrahman A. Almehizia Ayman H. Kamel 《RSC advances》2021,11(61):38774
All-solid state screen-printed electrodes were fabricated for chlorogenic acid (CGA) detection. The screen-printed platforms were modified with multi-walled carbon nanotubes (MWCNTs) to work as a lipophilic solid-contact transducer. The sensing-membrane was plasticized with a suitable solvent mediator and incorporating [NiII(bathophenanthroline)3][CGA]2 complex as a sensory material. In a 30 mM phosphate solution (buffer, pH 6), the sensor revealed a Nernstian-response towards CGA ions with a slope of −55.1 ± 1.1 (r2 = 0.9997) over the linear range 1.0 × 10−7 to 1.0 × 10−3 (0.035–354.31 μg mL−1) with a detection limit 7.0 × 10−8 M (24.8 ng mL−1). It revealed a stable potentiometric response with excellent reproducibility and enhanced selectivity over several common ions. Short-term potential stability and the interfacial sensor capacitance was estimated using both electrochemical-impedance spectroscopy (EIS) and chronopotentiometry techniques. The presented electrochemical platform revealed the merits of design simplicity, ease of miniaturization, good potential-stability, and cost-effectiveness. It is successfully applied to CGA determination in different coffee beans extracts and juice samples. The data obtained were compared with those obtained by liquid chromatography reference method (HPLC).All-solid state screen-printed electrodes were fabricated for chlorogenic acid (CGA) detection. 相似文献
53.
Natarajan Sisubalan Chandrasekaran Karthikeyan Venugopal Senthil Kumar Kokkarachedu Varaprasad Abdulrahman Syed ahamed Haja Hameed Ramar Vanajothi Rotimi Sadiku 《RSC advances》2021,11(49):30623
Mishandling of antibiotics often leads to the development of multiple drug resistance (MDR) among microbes, resulting in the failure of infection treatments and putting human health at great risk. As a response, unique nanomaterials with superior bioactivity must be developed to combat bacterial infections. Herein, CeO2-based nanomaterials (NMs) were synthesized by employing cerium(iii) nitrate and selective alkaline ions. Moreover, the influence of alkaline ions on CeO2 was investigated, and their characteristics, viz.: biochemical, structural, and optical properties, were altered. The size of nano Ba-doped CeO2 (BCO) was ∼2.3 nm, relatively smaller than other NMs and the antibacterial potential of CeO2, Mg-doped CeO2 (MCO), Ca-doped CeO2 (CCO), Sr-doped CeO2 (SCO), and Ba-doped CeO2 (BCO) NMs against Streptococcus mutans (S. mutans) and Staphylococcus aureus (S. aureus) strains was assessed. BCO outperformed all NMs in terms of antibacterial efficacy. In addition, achieving the enhanced bioactivity of BCO due to reduced particle size facilitated the easy penetration into the bacterial membrane and the presence of a sizeable interfacial surface. In this study, the minimum quantity of BCO required to achieve the complete inhibition of bacteria was determined to be 1000 μg mL−1 and 1500 μg mL−1 for S. mutans and S. aureus, respectively. The cytotoxicity test with L929 fibroblast cells demonstrated that BCO was less toxic to healthy cells. Furthermore, BCO did not show any toxicity and cell morphological changes in the L929 fibroblast cells, which is similar to the control cell morphology. Overall, the results suggest that nano BCO can be used in biomedical applications, which can potentially help improve human health conditions.The highest antibacterial activity was achieved for Ba-doped CeO2 (BCO) NMs and is suitable for healthcare applications. 相似文献
54.
Abdulrahman M. Alfuraih Samiah A. Alotaiby Mohammed J. Alsaadi Hanifa A. Bukhari Ali M. Aldhebaib Rafat S. Mohtasib 《Saudi medical journal》2021,42(10):1057
Objectives:To assess the usefulness of sonographically measured anogenital distance (AGD) in predicting fetal gender in Saudi fetuses during the first trimester and to provide normal reference centiles for AGD.Methods:A retrospective cohort study was conducted at King Faisal Specialist Hospital and Research Center, Riyadh, Saudi Arabia between November 2020 and May 2021. The ultrasound scans of 313 singleton pregnancies between 11–13 plus 6 gestational weeks and their gender-at-birth were collected. Anogenital distance was measured from the inferior base of the genital tubercle to the rump. Binominal logistic regression and receiver operating characteristic curves (ROC) evaluated the predictive performance of AGD for determining fetal gender.Results:There was a significant difference of approximately 15% in mean AGD between female (5.92 mm [95% CI= 6.70, 6.14]) and male (6.80 mm [95% CI= 6.61,7.00]) fetuses (p<0.001). Anogenital distance significantly correlated with gestational age (r=0.573, p<0.001) and crown-rump length (r=0.562, p<0.001). The logistic regression determined AGD as a significant predictor of fetal gender (p<0.001). However, ROC analysis showed that overall accuracies were low at 68% (p=0.001) for 11 weeks, 70% (p<0.001) for 12 weeks, and 64% (p=0.017), and for 13 weeks. The average AGD of our Saudi cohort was longer than what the literature reported from other populations.Conclusion:The first-trimester ultrasound evaluation of AGD was feasible and reliable. It showed a difference between the genders but did not yield high predictive accuracy. Future research should consider racial factors when evaluating AGD. 相似文献
55.
Roaa S. Gassas Ahmed N. Absi Abdulrahman A. Alghamdi Ahmed S. Alsaeed Sameer M. Alamoudi Ihab Y. Hemaidi Majed D. Alahmadi Walaa A. Rajkhan Mannar M. Khalil Saleem K. Dadah Ahmed S. Higazi Amani S. Ahmed 《Saudi medical journal》2021,42(8):847
Objectives:To assess local epidemiology and risk factors for bacterial, fungal, and viral infections among the autologous bone marrow transplant population.Methods:This study is a retrospective correlational cohort design comprising 150 adult patients who underwent autologous transplants at Princess Noorah Oncology Center, Jeddah, Saudi Arabia between 2014 and 2020.Results:The study findings indicate that bacterial infection prevalence differed significantly across the different disease status pre-salvage as patients with the relapsed disease were more likely to have bacterial infections. The median of engraftment days differed significantly between those who had a bacterial infection and those who did not. Interestingly, previous pneumonia infection had a positive relationship with the number of hospital stays.Conclusions:Bacterial infections are the dominant type of infection among the autologous patient population. The research reflects authentic practice and reports unique characteristics of autologous transplant patients in terms of the prevalence and types of infection these patients experience. 相似文献
56.
Tamer A. Mesallam Medhat Yousef Ilona Anderson Yassin Abdelsamad Sara Alkhamiss Abdulrahman Alsanosi 《Saudi medical journal》2021,42(9):1031
Objectives:To validate an Arabic version of the LittlEARS® Early Speech Production Questionnaire (LEESPQ), which assesses the early development of speech and language in infants between 0 and 18 months, in Arabic-speaking children with normal hearing in Saudi Arabia.Methods:This is a cross-sectional study conducted in the city of Riyadh, Saudi Arabia between September and December 2020. Parents completed the LEESPQ regarding their child’s speech production development. To assess the ability of normal hearing children aged 0-18 months in developing speech and language production, a norm curve has been generated based on the standardized values that were calculated from the Arabic normal-hearing data set.Results:A total of 198 questionnaires were analyzed. The total score on the LEESPQ correlated with age, gender, and bilingualism. A norm curve for early speech production in children with normal hearing was created.Conclusion:The Arabic version of LEESPQ appears to be a valid questionnaire that can be used in the assessment of early language and speech development of Arabic-speaking children with normal hearing in the age range of 0-18 months. The Arabic version of the LEESPQ might also be a useful tool to detect developmental delays and hearing disorders in young children. 相似文献
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58.
Expression of Salivary S100A7 Levels in Stage I Oral Submucous Fibrosis: A Clinical and Laboratory Study 下载免费PDF全文
Muhammad Arsalan RaffatNaila Irum HadiOsama AlghamdiKhulud Abdulrahman Al-AaliModhi Al DeebTariq AbduljabbarFahim Vohra 《Asian Pacific journal of cancer prevention》2020,21(4):1115-1119
Background: Oral submucous fibrosis (OSF) is a chronic debilitating condition characterized by juxta-epithelial fibrosis. The main etiological agent associated with the high-risk precancerous condition is areca nut use. S100A7 is a member of the largest calcium-binding proteins exclusively found in vertebrates and are associated with the regulation of numerous intracellular and extracellular functions. The aim of this study was to investigate the expression of protein S100A7 in salivary samples of individuals with stage I OSF and healthy controls. Methods: This study included 63 participants, 30 of whom had OSF stage I and 33 healthy controls. Nonprobability quota sampling technique was utilized for recruitment of the study participants. A structured baseline questionnaire was used to collect demographic data. Saliva samples were collected by passive droll technique in a sterile container. Salivary levels of S100A7 were quantified by enzyme-linked immunosorbent assay. For the normality of the data Shapiro Wilk test was performed. Student t-test was commuted to evaluate the expression of S100A7 protein expression between both the study groups. Results: The mean salivary S100A7 value for stage I OSF group was 0.334 ng/ml, compared to 0.172 ng/ml for healthy controls. Student t-test reported a statistically significant difference, indicating higher levels of S100A7 in stage I OSF group than in healthy controls (p < 0.001). In the individual group analysis, a significant negative correlation was found between salivary S100A7 and duration of areca nut use (r = –0.45, p = 0.009) and gutka chewing (r = –0.20, p = 0.03), while a significant positive correlation was found between salivary S100A7 and mouth opening (r = 0.03, p = 0.04). Conclusions: Higher levels of S100A7 protein level was seen in stage I OSF group in comparison to the healthy individuals. Results of our study suggest that S100A7 could be used as a surrogate assessment to identify patients at risk of OSF development. 相似文献
59.
Ebtissam Saleh Al-Meghaiseeb Mulfi Mubarak Al-Otaibi Abdulrahman Al-Robayan Reem Al-Amro Ahmd Saad Al-Malki Misbahul Arfin Abdulrahman K Al-Asmari 《World journal of gastroenterology : WJG》2015,21(3):897-904
AIM:To study the association of apolipoprotein E(APOE) polymorphisms with the susceptibility ofinflammatory bowel disease(IBD) in Saudi patients.METHODS:APOE genotyping was performed to evaluate the allele and genotype frequencies in 378 Saudi subjects including IBD patients with ulcerative colitis(n = 84) or Crohn's disease(n = 94) and matched controls(n = 200) using polymerase chain reaction and reverse-hybridization techniques.RESULTS:The frequencies of the APOE ε2 allele and ε2/ε3 and ε2/ε4 genotypes were significantly higher in IBD patients than in controls(P 0.05),suggesting that the ε2 allele and its heterozygous genotypes may increase the susceptibility to IBD.On the contrary,the frequencies of the ε3 allele and ε3/ε3 genotype were lower in IBD patients as compared to controls,suggesting a protective effect of APOE ε3 for IBD.The prevalence of the ε4 allele was also higher in the patient group compared to controls,suggesting that the ε4 allele may also increase the risk of IBD.Our results also indicated that the APOE ε4 allele was associated with an early age of IBD onset.No effect of gender or type of IBD(familial or sporadic) on the frequency distribution of APOE alleles and genotypes was noticed in this study.CONCLUSION:APOE polymorphism is associated with risk of developing IBD and early age of onset in Saudi patients,though further studies with a large-size population are warranted. 相似文献
60.
Lutfiah Al-Turk James Wawrzynski Su Wang Paul Krause George M. Saleh Hend Alsawadi Abdulrahman Zaid Alshamrani Tunde Peto Andrew Bastawrous Jingren Li Hongying Lilian Tang 《Eye (London, England)》2022,36(3):524
BackgroundIn diabetic retinopathy (DR) screening programmes feature-based grading guidelines are used by human graders. However, recent deep learning approaches have focused on end to end learning, based on labelled data at the whole image level. Most predictions from such software offer a direct grading output without information about the retinal features responsible for the grade. In this work, we demonstrate a feature based retinal image analysis system, which aims to support flexible grading and monitor progression.MethodsThe system was evaluated against images that had been graded according to two different grading systems; The International Clinical Diabetic Retinopathy and Diabetic Macular Oedema Severity Scale and the UK’s National Screening Committee guidelines.ResultsExternal evaluation on large datasets collected from three nations (Kenya, Saudi Arabia and China) was carried out. On a DR referable level, sensitivity did not vary significantly between different DR grading schemes (91.2–94.2.0%) and there were excellent specificity values above 93% in all image sets. More importantly, no cases of severe non-proliferative DR, proliferative DR or DMO were missed.ConclusionsWe demonstrate the potential of an AI feature-based DR grading system that is not constrained to any specific grading scheme.Subject terms: Diagnosis, Medical imaging 相似文献