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1.
RSC Adv ; 14(11): 7540-7550, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38440265

RESUMO

In this study, we investigated Cu-Co ferrite nanofibers (NFs) that were synthesized for the first time employing the electrospinning technique. The structure, phase purity and crystallite size of all the prepared NFs were revealed by powder X-ray diffraction (PXRD) analysis. The NFs crystallized in the Fd3̄m (no. 227) space group and the cation distribution arrangement over distinct sites in their structure was analyzed. Scanning electron microscopy (SEM) together with energy-dispersive X-ray (EDX) spectroscopy analysis showed the microstructure of the NFs and verified their expected chemical compositions. High-resolution transmission electron microscopy (TEM) images confirmed the fibrous nature and the construction of the NFs. The band gap energies derived from the UV-vis reflectance spectra showed a blue shift with an increase in the amount of Cu in the sample from 1.42 eV to 1.86 eV. Magnetization (M) as a function of magnetic field (H) measurements performed at ambient and low temperatures showed the ferrimagnetic behavior of all the NFs. The magnetic parameters including coercivity (Hc), saturation magnetization (Ms), remanent magnetization (Mr), and squareness ratio were determined from the recorded magnetization curves. At 300 K, Ms was reduced from 78.8 to 42.4 emu g-1, Mr reduced from 22.8 to 7.6 emu g-1 and the Bohr magneton reduced from 3.3 to 1.8µB with an increase in the content of Cu in the samples. The same trend was observed at 10 K, where Ms was reduced from 93.7 to 50.9 emu g-1, Mr reduced from 60.9 to 35.9 emu g-1 and the Bohr magneton reduced from 3.94 to 2.16µB. Alternatively, Hc has the highest values for x = 0 (850 Oe at 300 K and 5220 Oe at 10 K) and x = 0.6 (800 Oe at 300 K and 5400 Oe at 10 K). The anti-cancer activity of the NFs was evaluated using the MTT cell viability assay, showing a reduction in the viability of both HCT-116 and HeLa cancer cells compared to non-cancerous HEK-293 cells after treatment with the NFs. Apoptotic activity was examined by DAPI staining, where treatment with the NFs induced chromatin condensation and nuclear disintegration in HCT-116 cells.

2.
Metabolomics ; 20(1): 7, 2023 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-38114836

RESUMO

INTRODUCTION: Nuclear Magnetic Resonance (NMR) spectroscopy stands as a preeminent analytical tool in the field of metabolomics. Nevertheless, when it comes to identifying metabolites present in scant amounts within various types of complex mixtures such as plants, honey, milk, and biological fluids and tissues, NMR-based metabolomics presents a formidable challenge. This predicament arises primarily from the fact that the signals emanating from metabolites existing in low concentrations tend to be overshadowed by the signals of highly concentrated metabolites within NMR spectra. OBJECTIVES: The aim of this study is to tackle the issue of intense sugar signals overshadowing the desired metabolite signals, an optimal pulse sequence with band-selective excitation has been proposed for the suppression of sugar's moiety signals (SSMS). This sequence serves the crucial purpose of suppressing unwanted signals, with a particular emphasis on mitigating the interference caused by sugar moieties' signals. METHODS: We have implemented this comprehensive approach to various NMR techniques, including 1D 1H presaturation (presat), 2D J-resolved (RES), 2D 1H-1H Total Correlation Spectroscopy (TOCSY), and 2D 1H-13C Heteronuclear Single Quantum Coherence (HSQC) for the samples of dates-flesh, honey, a standard stock solution of glucose, and nine amino acids, and commercial fetal bovine serum (FBS). RESULTS: The outcomes of this approach were significant. The suppression of the high-intensity sugar signals has considerably enhanced the visibility and sensitivity of the signals emanating from the desired metabolites. CONCLUSION: This, in turn, enables the identification of a greater number of metabolites. Additionally, it streamlines the experimental process, reducing the time required for the comparative quantification of metabolites in statistical studies in the field of metabolomics.


Assuntos
Misturas Complexas , Metabolômica , Metabolômica/métodos , Espectroscopia de Ressonância Magnética/métodos , Misturas Complexas/química , Aminoácidos , Glucose
3.
BMC Med Educ ; 23(1): 655, 2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37684578

RESUMO

BACKGROUND: Medical residency is a part of postgraduate medical education and involves clinical training in a selected specialty. It is a challenging step in a physician's professional development. This study aims to estimate the impact of the residency training program and demographic factors on the trainee's state of well-being (SOW). METHODS: This was an observational cross-sectional study carried out in the year 2019-2020, which aimed to measure the SOW of residents undergoing clinical training in Riyadh, Saudi Arabia. A total of 260 residents participated in the study. A self-administered validated online the World Health Organization, Quality of Life Scale questionnaire- BREF was distributed to collect the data. The collected information on four different domains was analysed and compared across the baseline characteristics and different specialties. When appropriate, the independent sample t-test, bivariate correlation analysis, and ANOVA tests were used. RESULTS: A total of 260 resident responses were included in the final analysis The results revealed a significant difference in physical health scores (p = 0.006), social relationship scores (p = 0.038), and environmental scores (p < 0.001) while no significant difference was found in psychological health scores among the physicians' specialties (p = 0.053). Post hoc comparison found statistically significant variations in the physical health domain between the medical and emergency specialties (p = 0.007), as well as surgical and emergency specialties (p = 0.024). There was also a significant difference between medical and emergency specialties (p = 0.008) in the social relationship domain. In the environment domain, significant variation was reported between medical specialties and emergency specialties (p = 0.001), as well asbetween surgical specialties and emergency specialties (p = 0.045). Female residents reported significantly lower quality of life in the physical (p = 0.020) and psychological (p = 0.032) domains. CONCLUSIONS: A significant relationship was found between physical, social, and environmental domains according to residents' specialties. The factors that affected one or more domains included age, female gender, marital status, disease status, the number of on-calls received, and workload. We emphasize the importance of implementing policies to regulate working hours and on-call schedules as well as prioritizing mental health support.


Assuntos
Medicina , Qualidade de Vida , Feminino , Animais , Arábia Saudita , Estudos Transversais , Correlação de Dados
4.
Front Pharmacol ; 14: 1213824, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37521476

RESUMO

The revolution of biomedical applications has opened new avenues for nanotechnology. Zinc Chromium vanadate nanoparticles (VCrZnO4 NPs) have emerged as an up-and-coming candidate, with their exceptional physical and chemical properties setting them apart. In this study, a one-pot solvothermal method was employed to synthesize VCrZnO4 NPs, followed by a comprehensive structural and morphological analysis using a variety of techniques, including X-Ray diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, Energy-dispersive X-ray, and X-ray photoelectron spectroscopy. These techniques confirmed the crystallinity of the NPs. The VCrZnO4 NPs were tested for their antibacterial activity against primary contaminants such as Enterobacteriaceae, including Shigella flexneri, Salmonella cholerasis, and Escherichia coli, commonly found in hospital settings, using the broth dilution technique. The results indicated a stronger antibacterial activity of VCrZnO4 NPs against Shigella and Salmonella than E. coli. Electron microscopy showed that the NPs caused severe damage to the bacterial cell wall and membrane, leading to cell death. In addition, the study evaluated the anticancer activities of the metal complexes in vitro using colorectal cancer cells (HCT-116) and cervical cancer cells (HELA), along with non-cancer cells and human embryonic kidney cells (HEK-293). A vanadium complex demonstrated efficient anticancer effects with half-inhibitory concentrations (IC50) of 38.50+3.50 g/mL for HCT-116 cells and 42.25+4.15 g/mL for HELA cells. This study highlights the potential of Zinc Chromium vanadate nanoparticles as promising candidates for antibacterial and anticancer applications. Various advanced characterization techniques were used to analyze the properties of nanomaterials, which may help develop more effective and safer antibacterial and anticancer agents in the future.

5.
Ann Med Surg (Lond) ; 81: 104428, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36147136

RESUMO

Background: As children with down syndrome (DS) usually have significant morbidities, they can also represent a significant burden on their caregivers and impact their quality of life (QoL). We conducted this study to investigate whether or not having DS children can impact the different domains of the QoL of their caregivers in Saudi Arabia. Methods: This is a cross-sectional phenomenological qualitative research study that was conducted in a tertiary care hospital, Riyadh, Saudi Arabia. To assess the study outcomes, we used the WHOQOL-BREF to assess the different domains of the QoL. Results: We have included 261 caregivers to DS children that responded to our questionnaire. The mean (SD) scores for the WHOQOL-BREF domains were 84 (±15), 88 (±15), 41 (±10), and 105 (±24), including the physical, psychological, social relations, and environmental domains, respectively. There was a significant difference between all of the scores that have been reported for these domains (P-value <0.001). Furthermore, educational level and the number of children were significantly associated with the psychological and physical domains, while the number of children was the only significant variable with the social relation. Finally, educational level, number of children, and average monthly income were all significantly correlated with the environmental domain. Conclusion: Our study indicates that the QoL of caregivers to DS children is significantly impacted in the different domains, indicating the urgent need to apply adequate interventions.

6.
Saudi Med J ; 43(8): 873-880, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35964954

RESUMO

OBJECTIVES: To discuss and summarize the scholarly published literature on the difference in obesity rate in treated and untreated attention deficit hyperactivity disorder (ADHD) patients to evaluate the influence of ADHD medication on weight status in these individuals. METHODS: PubMed, Cochrane Library, and Google Scholar databases were searched for eligible articles from January to December 2020 using the following medical subject headings (MeSH) terms: "attention deficit hyperactivity disorder and other hyperactivity disorders", "obesity and overweight", "obesity treatment". RESULTS: A total of 19,449 study participants included in selected 8 studies were assessed with respect to the prevalence of obesity in medicated and unmedicated subgroups of ADHD patients. The total number of ADHD patients with the prescribed medication was 10,279, while the number of unmedicated ADHD patients was 9,170. The odds ratio was 0.65 with a 95% confidence interval of 0.50 to 0.84 favoring regular medical treatment for management of obesity in case of patients with ADHD. CONCLUSION: The prevalence of obesity observed in treated ADHD patients was significantly lower compared to that in unmedicated patients. This result suggests that the treatment is not only important for controlling ADHD manifestations but is also associated with lower body mass index. Therefore, further prospective studies with large sample size are required for controlling the confounding factors such as comorbidities and medication status.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/epidemiologia , Humanos , Obesidade/complicações , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Prevalência , Estudos Prospectivos
7.
Front Pediatr ; 10: 708217, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35463885

RESUMO

Background: A home environment that promotes learning is a significant factor in school performance in which children's parents are involved in their education. However, little study has focused on parents' reading-related beliefs or the relationship between parents' literacy beliefs and behaviors. Methods: This cross-sectional study describes the range of parents' reported literacy beliefs and behaviors and examines whether an association exists in Saudi Arabia. It was conducted on a convenient sample of 100 parents using a web-based self-administrated shared with families in Developmental and Behavioral Pediatrics clinics at multiple sites utilizing the Parents' Perceptions of Literacy Learning Interview Schedule (PPLLIS). Results: There were 83 mothers and 17 fathers; 90% had a university degree or higher. Parents' beliefs ranged between 87 and 123, with a mean of 103.54 ± 8.05, indicating more holistic perceptions than skills-based ones. There was only a positive significant correlation between parents' beliefs and behaviors regarding literacy activities. However, those participating in literacy activities with their kids were more holistic parents and scored the top one-third on the PPLLIS. Conclusion: Parents' beliefs and their reported behaviors are found to be significantly impacted by their educational levels. Therefore, future investigations and national campaigns are encouraged to improve parents' educational levels, especially in urban areas.

8.
ACS Omega ; 6(15): 10266-10280, 2021 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-34056181

RESUMO

[Ni0.4Cu0.2Zn0.4](Fe2-x Dy x )O4 spinel ferrite nanoparticles with different Dy3+ concentrations (0.00 ≤ x ≤ 0.04) were prepared by a citrate sol-gel auto-combustion technique. A strong correlation among Dy concentration, structural parameters, and magnetic, electrical, and microwave properties was established. An increase in the Dy3+ concentration is the reason for a rise in the crystal structure parameters (due to different ionic radii of Fe and Dy ions) and a slight increase in the average particle size with a minor reduction in the specific surface area. It was observed that Dy3+ ions prefer to occupy the octahedral B site due to their large ionic radius (0.91 Å). The explanation of the electrical and magnetic properties was given in terms of the features of Dy3+-O2--Fe3+ dysprosium-oxygen-iron indirect exchange. The occurrence of the intensive changes in amplitude-frequency characteristics was observed from 1.6 to 2.7 GHz. The explanation of electromagnetic absorption was given in terms of the peculiarities of the microstructure (resonance of domain boundaries). The results open perspectives in the utilization of [Ni0.4Cu0.2Zn0.4](Fe2-x Dy x )O4 spinel ferrite nanoparticles as functional materials for targeted drug delivery and hyperthermia applications.

9.
Molecules ; 25(20)2020 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-33050240

RESUMO

Studying disease models at the molecular level is vital for drug development in order to improve treatment and prevent a wide range of human pathologies. Microbial infections are still a major challenge because pathogens rapidly and continually evolve developing drug resistance. Cancer cells also change genetically, and current therapeutic techniques may be (or may become) ineffective in many cases. The pathology of many neurological diseases remains an enigma, and the exact etiology and underlying mechanisms are still largely unknown. Viral infections spread and develop much more quickly than does the corresponding research needed to prevent and combat these infections; the present and most relevant outbreak of SARS-CoV-2, which originated in Wuhan, China, illustrates the critical and immediate need to improve drug design and development techniques. Modern day drug discovery is a time-consuming, expensive process. Each new drug takes in excess of 10 years to develop and costs on average more than a billion US dollars. This demonstrates the need of a complete redesign or novel strategies. Nuclear Magnetic Resonance (NMR) has played a critical role in drug discovery ever since its introduction several decades ago. In just three decades, NMR has become a "gold standard" platform technology in medical and pharmacology studies. In this review, we present the major applications of NMR spectroscopy in medical drug discovery and development. The basic concepts, theories, and applications of the most commonly used NMR techniques are presented. We also summarize the advantages and limitations of the primary NMR methods in drug development.


Assuntos
Desenho de Fármacos , Descoberta de Drogas/métodos , Espectroscopia de Ressonância Magnética/métodos , Humanos
10.
Antibiotics (Basel) ; 9(9)2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32899195

RESUMO

Recently, titanium dioxide (TiO2) nanomaterials have gained increased attention because of their cost-effective, safe, stable, non-toxic, non-carcinogenic, photocatalytic, bactericidal, biomedical, industrial and waste-water treatment applications. The aim of the present work is the synthesis of electrospun TiO2 nanofibers (NFs) in the presence of different amounts of air-argon mixtures using sol-gel and electrospinning approaches. The physicochemical properties of the synthesized NFs were examined by scanning and transmission electron microscopies (SEM and TEM) coupled with energy-dispersive X-ray spectroscopy (EDX), ultraviolet-visible spectroscopy and thermogravimetric analyzer (TGA). The antibacterial and antibiofilm activity of synthesized NFs against Gram-negative Pseudomonas aeruginosa and Gram-positive methicillin-resistant Staphylococcusaureus (MRSA) was investigated by determining their minimum bacteriostatic and bactericidal values. The topological and morphological alteration caused by TiO2 NFs in bacterial cells was further analyzed by SEM. TiO2 NFs that were calcined in a 25% air-75% argon mixture showed maximum antibacterial and antibiofilm activities. The minimum inhibitory concentration (MIC)/minimum bactericidal concentration (MBC) value of TiO2 NFs against P. aeruginosa was 3 and 6 mg/mL and that for MRSA was 6 and 12 mg/mL, respectively. The MIC/MBC and SEM results show that TiO2 NFs were more active against Gram-negative P. aeruginosa cells than Gram-positive S. aureus. The inhibition of biofilm formation by TiO2 NFs was investigated quantitatively by tissue culture plate method using crystal violet assay and it was found that TiO2 NFs inhibited biofilm formation by MRSA and P. aeruginosa in a dose-dependent manner. TiO2 NFs calcined in a 25% air-75% argon mixture exhibited maximum biofilm formation inhibition of 75.2% for MRSA and 72.3% for P. aeruginosa at 2 mg/mL, respectively. The antibacterial and antibiofilm results suggest that TiO2 NFs can be used to coat various inanimate objects, in food packaging and in waste-water treatment and purification to prevent bacterial growth and biofilm formation.

11.
Metabolites ; 9(7)2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31252628

RESUMO

Over the past two decades, nuclear magnetic resonance (NMR) has emerged as one of the three principal analytical techniques used in metabolomics (the other two being gas chromatography coupled to mass spectrometry (GC-MS) and liquid chromatography coupled with single-stage mass spectrometry (LC-MS)). The relative ease of sample preparation, the ability to quantify metabolite levels, the high level of experimental reproducibility, and the inherently nondestructive nature of NMR spectroscopy have made it the preferred platform for long-term or large-scale clinical metabolomic studies. These advantages, however, are often outweighed by the fact that most other analytical techniques, including both LC-MS and GC-MS, are inherently more sensitive than NMR, with lower limits of detection typically being 10 to 100 times better. This review is intended to introduce readers to the field of NMR-based metabolomics and to highlight both the advantages and disadvantages of NMR spectroscopy for metabolomic studies. It will also explore some of the unique strengths of NMR-based metabolomics, particularly with regard to isotope selection/detection, mixture deconvolution via 2D spectroscopy, automation, and the ability to noninvasively analyze native tissue specimens. Finally, this review will highlight a number of emerging NMR techniques and technologies that are being used to strengthen its utility and overcome its inherent limitations in metabolomic applications.

12.
Inorg Chem ; 57(7): 3713-3719, 2018 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-29537828

RESUMO

The new thioaluminogermanate Na(AlS2)(GeS2)4 (1) was successfully synthesized by a direct combination reaction. The compound crystallizes in the monoclinic space group P21/ n (no. 14) with unit cell parameters a = 6.803(3) Å, b = 38.207(2) Å, c = 6.947(4) Å, and ß = 119.17(3)°. The crystal structure is composed of a [(AlS2)(GeS2)4]- 3D polyanionic network, in which Al and Ge atoms share the atomic positions and Na cations occupy the channels and voids formed by the connection of (Ge/Al)S4 tetrahedra. The title compound shows a cation-exchange property with monovalent Ag+ and Cu+ ions at room temperature in solvent media, resulting in the formation of the isostructural compounds Ag(AlS2)(GeS2)4 (2) and Cu(AlS2)(GeS2)4 (3), respectively. The ion-exchange products Ag(AlS2)(GeS2)4 (2) and Cu(AlS2)(GeS2)4 (3) show higher air stability and narrower bandgap energies compared to those of the parent compound Na(AlS2)(GeS2)4 (1).

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