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Background: Skin is regarded as an essential first line of defense against harmful pathogens and it hosts an ecosystem of microorganisms that create a widely diverse skin microbiome. In chronic wounds, alterations in the host-microbe interactions occur forming polymicrobial biofilms that hinder the process of wound healing. Ribavirin, an antiviral drug, possesses antimicrobial activity, especially against Pseudomonas aeruginosa and Candida albicans, which are known as the main opportunistic pathogens in chronic wounds. Rationale: In this study, electrospun nanofiber systems loaded with ribavirin were developed as a potential wound dressing for topical application in chronic wounds. Ribavirin was chosen in this study owing to the emerging cases of antimicrobial (antibiotics and antifungal) resistance and the low attempts to discover new antimicrobial agents, which encouraged the repurposing use of current medication as an alternative solution in case of resistance to the available agents. Additionally, the unique mechanism of action of ribavirin, i.e., perturbing the bacterial virulence system without killing or stopping their growth and rendering the pathogens disarmed, might be a promising choice to prevent drug resistance. Cyclodextrin (CD) was utilized to formulate ribavirin as an electrospun nanofibers delivery system to enhance the absorption and accelerate the release of ribavirin for topical use. Results: The results demonstrated a successful ribavirin nanofibers fabrication that lacked beads and pores on the nanofibrous surfaces. Ribavirin underwent a physical transformation from crystalline to amorphous form, as confirmed by X-ray diffraction analysis. This change occurred due to the molecular dispersion after the electrospinning process. Additionally, the CD enhanced the encapsulation efficiency of ribavirin in the nanofibers as observed from the drug-loading results. Polyvinylpyrrolidone (PVP) and CD increased ribavirin released into the solution and the disintegration of fibrous mats which shrank and eventually dissolved into a gel-like substance as the ribavirin-loaded fibers began to break down from their border toward the midpoint. Cytotoxicity of ribavirin and CD was evaluated against human dermal fibroblasts (HFF-1) and the results showed a relatively safe profile of ribavirin upon 24-hour cell exposure, while CD was safe within 24- and 48-hour. Conclusion: This study provides valuable insights into the potential application of our nanofibrous system for treating chronic wounds; however, further antimicrobial and in-vivo studies are required to confirm its safety and effectiveness.
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Erectile dysfunction (ED) is a growing health condition that needs safe and effective therapy. One of the main common treatments is sildenafil which is used in clinics for managing erectile dysfunction by enhancing the blood supply to the penis. In the current study, sildenafil was formulated as nanofibers and mixed with the root extract of Glycyrrhiza glabra (glycyrrhizin) as a natural sweetener to be administrated in the buccal cavity for enhanced drug bioavailability, rapid drug absorption and improved patient compliance. The formulated dual-loaded nanofibers were evaluated by measuring diameter, disintegration, drug loading efficiency, drug release profile, and in vitro cell viability assessment. The results showed that the sildenafil/glycyrrhizin-loaded fibers had a diameter of 0.719 ± 0.177 µm and lacked any beads and pores formation on their surfaces. The drug loading and encapsulation efficiency for sildenafil were measured as 52 ± 7 µg/mg and 67 ± 9 %, respectively, while they were 290 ± 32 µg/mg and 94 ± 10 %, respectively, for glycyrrhizin. The release rate of sildenafil and glycyrrhizin demonstrated a burst release in the first minute, followed by a gradual increment until a complete release after 120 min. The in vitro cell viability evaluation exhibited that the application of sildenafil and glycyrrhizin is safe upon 24-hour treatment on human skin fibroblast cells at all used concentrations (i.e., ≤ 1,000 and 4,000 µg/mL, respectively). However, the application of sildenafil-glycyrrhizin combination (in a ratio of 1:4) demonstrated more than 80 % cell viability at concentrations of ≤ 250 and 1000 µg/mL, respectively, following 24-hour cell exposure. Therefore, sildenafil/glycyrrhizin dual-loaded PVP nanofibers showed a potential buccal therapeutic approach for erectile dysfunction management.
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This study investigates the effectiveness of telemedicine in managing glucose levels in insulin-treated diabetes patients compared to standard care. Adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) criteria and Cochrane's risk of bias tool, an analysis of five selected studies reveals telemedicine as a potent tool in diabetes management. Fasting blood sugar (FBS) test results from two studies involving an eight-hour fast with 109 participants demonstrate a significant superiority of telemedicine over usual care (Tau2 = 1.63; Chi2 = 1.01, df = 1, P = 0.32; Z = 2.43, P = 0.02), highlighting its potential in short-term blood sugar stabilization. Postprandial plasma glucose (PPBG) test outcomes suggest comparable efficacy in managing post-meal blood glucose levels with telemedicine. Additionally, analysis of glycated hemoglobin (HbA1c) levels across all five studies indicates telemedicine's equivalence to traditional care in maintaining HbA1c levels among insulin-treated patients, affirming its efficacy in primary care. While emphasizing telemedicine's effectiveness in managing FBS levels, a critical aspect of diabetes control, among patients utilizing insulin therapy in primary care, the study underscores the need for more extensive, large-scale research to fully comprehend its impact on diabetes management.
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Much attention has been gained on green silver nanoparticles (green-AgNPs) in the medical field due to their remarkable effects against multi-drug resistant (MDR) microorganisms and targeted cancer treatment. In the current study, we demonstrated a simple and environment-friendly (i.e., green) AgNP synthesis utilizing Jacobaea maritima aqueous leaf extract. This leaf is well-known for its medicinal properties and acts as a reducing and stabilizing agent. Nanoparticle preparation with the desired size and shape was controlled by distinct parameters; for instance, temperature, extract concentration of salt, and pH. The characterization of biosynthesized AgNPs was performed by the UV-spectroscopy technique, dynamic light scattering, scanning electron microscopy, X-ray diffraction, and Fourier-transform infrared. The successful formation of AgNPs was confirmed by a surface plasmon resonance at 422 nm using UV-visible spectroscopy and color change observation with a particle size of 37± 10 nm and a zeta potential of -10.9 ± 2.3 mV. SEM further confirmed the spherical size and shape of AgNPs with a size varying from 28 to 52 nm. Antibacterial activity of the AgNPs was confirmed against all Gram-negative and Gram-positive bacterial reference and MDR strains that were used in different inhibitory rates, and the highest effect was on the E-coli reference strain (MIC = 25 µg/mL). The anticancer study of AgNPs exhibited an IC50 of 1.37 µg/mL and 1.98 µg/mL against MCF-7 (breast cancer cells) and A549 (lung cancer cells), respectively. Therefore, this green synthesis of AgNPs could have a potential clinical application, and further in vivo study is required to assess their safety and efficacy.
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Asteraceae , Nanopartículas Metálicas , Prata/química , Nanopartículas Metálicas/química , Testes de Sensibilidade Microbiana , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos/química , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Química Verde/métodosRESUMO
The prevalence of type 2 diabetes (T2D) has been growing worldwide; hence, safe and effective antidiabetics are critically warranted. Recently, imeglimin, a novel tetrahydrotriazene compound, has been approved for use in T2D patients in Japan. It has shown promising glucose-lowering properties by improving pancreatic beta-cell function and peripheral insulin sensitivity. Nevertheless, it has several drawbacks, including suboptimal oral absorption and gastrointestinal (GI) discomfort. Therefore, this study aimed to fabricate a novel formulation of imeglimin loaded into electrospun nanofibers to be delivered through the buccal cavity to overcome the current GI-related adverse events and to provide a convenient route of administration. The fabricated nanofibers were characterized for diameter, drug-loading (DL), disintegration, and drug release profiles. The data demonstrated that the imeglimin nanofibers had a diameter of 361 ± 54 nm and DL of 23.5 ± 0.2 µg/mg of fibers. The X-ray diffraction (XRD) data confirmed the solid dispersion of imeglimin, favoring drug solubility, and release with improved bioavailability. The rate of drug-loaded nanofibers disintegration was recorded at 2 ± 1 s, indicating the rapid disintegration ability of this dosage form and its suitability for buccal delivery, with a complete drug release after 30 min. The findings of this study suggest that the developed imeglimin nanofibers have the potential to be given via the buccal route, thereby achieving optimal therapeutic outcomes and improving patient compliance.
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BACKGROUND: Medical students' career choices and motivations might be significantly impacted by the rapid advances in artificial intelligence (AI) and the recent hype around it. OBJECTIVE: This study aimed to assess the impact of AI on medical students' preferences for radiology as a future specialty choice. METHODS: A cross-sectional study was conducted between October and December 2021 among all medical students in the three regional medical colleges in Al-Qassim Province, Saudi Arabia. RESULTS: The survey resulted in 319 complete responses. Among the respondents, 26.96% considered radiology to be one of their top three future specialty choices. Only a minority of the respondents (23.2%) believed that radiologists would be replaced by AI during their lifetime. The misperceptions of the potential impact of AI led 22.26% of the students to be less likely to consider a career in radiology. Students with an interest in radiology were less influenced by such misperceptions (p=.01). Based on self-reported confidence measures, the basic understanding of AI was higher among students with an interest in radiology and students with prior exposure to AI (p<.05). CONCLUSION: The students' preferences for radiology as a future specialty choice were influenced by their misperceptions of the potential impact of AI on the discipline. Students' interest in radiology and prior exposure to AI helped them grasp AI and eliminate the hype around it.
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Radiologia , Estudantes de Medicina , Humanos , Inteligência Artificial , Estudos Transversais , Radiologia/educação , Radiologia/métodos , RadiografiaRESUMO
Chest pain in pediatric patients is a common concern in pediatric emergency departments (ED). In most cases, benign conditions are related to noncardiac causes, and only a minority of the cases are caused by heart disease. This research aimed to evaluate the causes and characteristics of chest pain among children in a pediatric emergency department. This retrospective study evaluated children younger than 14 years of age who presented to the emergency department of a general pediatric hospital in the Eastern area of Saudi Arabia with non-traumatic chest pain between 2017 and 2022. The data included socioeconomic information, physical examination findings, and the results of basic investigations, such as chest X-ray and electrocardiogram. The Chi-square test was performed to compare various etiologies, with a 5% significant level. The study evaluated 310 patients with a mean age of 9.1±2.7 years. The majority of children presenting with chest pain had normal physical examinations, except 3.3% who showed respiratory and cardiac findings. The diagnostic tests indicated pneumonia in 2.9% and arrhythmia in 2.1% of children. Most patients were discharged with a diagnosis of idiopathic or muscular chest pain. The majority of patients (95%) were treated symptomatically in outpatient settings, with just one patient requiring hospitalization. The most common cause of chest pain prompting a child to visit the ED was idiopathic chest pain. Therefore, this study highlights the significance of obtaining a comprehensive medical history and physical examination to reveal important clues and help avoid unnecessary tests.
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Dor no Peito , Serviço Hospitalar de Emergência , Humanos , Criança , Estudos Retrospectivos , Dor no Peito/diagnóstico , Dor no Peito/epidemiologia , Dor no Peito/etiologia , Hospitalização , Eletrocardiografia/efeitos adversosRESUMO
BACKGROUND: Transient osteoporosis of the hip, or acute bone marrow edema syndrome, is a rare condition characterized by a decrease in bone mineral density of the proximal femur, which resolves with conservative management over 6-24 months. At presentation, the patient complains of sudden onset of localized pain in the hip, which is aggravated by weight-bearing. However, the prevalence and risk factors for this condition are still unclear. Objective: This study aims to identify the prevalence of transient osteoporosis of the hip among patients who present with hip pain and underwent magnetic resonance imaging of the hip. METHOD: This is a retrospective investigation that involved collecting data from patients' records in a tertiary hospital in Saudi Arabia. Included candidates were patients who presented with hip pain, had an MRI done between 2016 and 2019 inclusive, and were older than 14 years. The collected data involved the age and gender of patients, the hip's affected side, and the diagnosis. Data analysis was executed through SPSS version 26 (IBM Corp., Armonk, NY). RESULTS: Three hundred and fourteen patients matched our inclusion criteria. The prevalence of transient osteoporosis of the hip was 2.5%. All of them were males and half were above 40 years, 50% had pain in the left side, and 75% had a small joint effusion. The femoral head was the most affected part of the joint in patients with transient osteoporosis of the hip. Among our patients, the most common cause of hip pain was gluteus medius tendonitis (12.9%), where 33.1% of patients with hip pain had normal examination and investigations, and 15.2% had more than one condition. Risk factors for transient osteoporosis of the hip are pain in the left hip joint (p-value=0.023) and an age between 41 and 50 years (p-value=0.012). CONCLUSION: The prevalence of transient osteoporosis of the hip is low, yet it requires confirmation by studies with a more robust design. Males older than 40 years and left-side hip pain are at higher risk.
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Infections contracted during healthcare delivery in a hospital or ambulatory setting are collectively referred to as healthcare-associated infections (HAIs). Healthcare workers and patients alike are vulnerable to serious problems as a result of the risk of HAIs. In the healthcare system, HAIs are considered among the most common and serious health problems. However, the occurrence of HAIs differs between different types of clinical departments within the hospital. Recently, the risk of HAIs has been increasing in radiology departments globally due to the central role of radiology in guiding clinical decisions for the diagnosis, treatment, and monitoring of different diseases from almost all medical specialties. The radiology department is particularly vulnerable to HAIs because it serves as a transit hub for infected patients, non-infected patients, and healthcare workers. Furthermore, as the number of patients referred to radiology and the length of patient contact time has increased, thanks to modern imaging techniques such as computed tomography and magnetic resonance imaging, the risk of HAIs has also increased significantly. With the increasing use of interventional radiological procedures, patients and healthcare workers face a potentially greater risk of contracting HAIs due to the invasive nature of such procedures. Although not exhaustive, we attempted through a literature search to provide a general overview of infection prevention and control practices, address HAIs in the radiology departments, and highlight the challenges and measures taken to control infection transmission in the radiology departments.
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BACKGROUND: Online summative assessment has emerged during the COVID-19 pandemic as an alternative to traditional examinations, bringing opportunities and challenges. The study aims to evaluate the feasibility and effectiveness of online structured oral examination (SOE) in radiology clerkships. The study identifies measures taken to successfully implement online SOE and minimize chances of cheating. It also discusses the challenges encountered and how they were addressed. METHODS: SOE percent scores of fourth-year medical students from two institutions were correlated with students' grade point average (GPA). The scores were compared among different institutions, students' genders, students' batches, examination versions, and examiners with different experience levels. Students' perceived satisfaction and concerns were captured using anonymous self-administered questionnaire. Technical problems and success rate of SOE implementation were recorded. Results were analyzed using descriptive and inferential statistics. RESULTS: A total of 79 students participated in the study, out of which 81.0% (n = 64) responded to the survey. SOE scores showed poor positive correlation with the students' GPAs (r = 0.22, and p = .09). Scores showed no significant difference between the two institutions or genders. Scores were also not significantly different between students who were examined by junior or senior examiners. All but one version of examination showed no significant difference in students' scores. No significant difference was observed in students' scores between each two subsequent batches who were exposed to the same examination version. CONCLUSION: Online summative SOE is a feasible alternative whenever face-to-face SOE could not be implemented provided that appropriate measures are taken to ensure its successful execution.
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In this preclinical two-dose mucosal immunization study, using a combination of S1 spike and nucleocapsid proteins with cationic (N3)/or anionic (L3) lipids were investigated using an intranasal delivery route. The study showed that nasal administration of low amounts of antigens/adjuvants induced a primary and secondary immune response in systemic IgG, mIL-5, and IFN-gamma secreting T lymphocytes, as well as humoral IgA in nasal and intestinal mucosal compartments. It is believed that recipients will benefit from receiving a combination of viral antigens in promoting a border immune response against present and evolving contagious viruses. Lipid adjuvants demonstrated an enhanced response in the vaccine effect. This was seen in the significant immunogenicity effect when using the cationic lipid N3. Unlike L3, which showed a recognizable effect when administrated at a slightly higher concentration. Moreover, the findings of the study proved the efficiency of an intranasally mucosal immunization strategy, which can be less painful and more effective in enhancing the respiratory tract immunity against respiratory infectious diseases.
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Epidermoid cysts are benign congenital extra-axial lesions commonly found in the posterior fossa. These lesions have a characteristic imaging appearance on computed tomography (CT) scan and magnetic resonance imaging (MRI), but occasionally they may exhibit atypical radiological features, showing unusual hyperintensity on T1-weighted images (T1WI). Currently, such atypical appearance is referred to as white epidermoid. We present the imaging features of 5 cases of white epidermoid cyst and discuss the possible underlying etiology of this unusual radiological appearance. We retrospectively searched our electronic radiology database from January 2005 to December 2015 for all intracranial epidermoid cysts, which were confirmed either by typical MRI appearance or histopathological examination. All white epidermoid cases were evaluated with non-enhanced CT scan and multisequential MRI. Histopathological correlation was carried out in four white epidermoid cases. A total of 61 patients with epidermoid cyst were found, of those 5 (8%) were considered white epidermoids. These consisted of 3 females and 2 males, ranging in age between 31-63 years (average age was 51.8 years). Three patients had lesions located in the posterior fossa. The 2 other patients had lesions in the suprasellar region, with extension to the right middle cranial fossa in one. All 5 lesions were hyperdense on CT scan and hyperintense on T1WI. One patient demonstrated evidence of transformation of a classic epidermoid to a white epidermoid after partial resection. Histopathologically, cholesterol clefts were seen in 3 epidermoid cysts, each which also showed microcalcifications, proteinaceous material or melanin. Hemorrhage was demonstrated in one additional lesion. White epidermoid cyst is an unusual intracranial lesion that should be considered when encountered with an extra-axial T1 hyperintense lesion. The cause of this hyperintensity is not clearly understood, but the presence of cholesterol, microcalcifications, proteinaceous content and rarely hemorrhage or melanin may be contributing factors.
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Encefalopatias/diagnóstico por imagem , Encefalopatias/patologia , Cisto Epidérmico/diagnóstico por imagem , Cisto Epidérmico/patologia , Adulto , Fossa Craniana Posterior , Imagem de Tensor de Difusão , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios XRESUMO
Skeletal changes are a common complication in patients with chronic kidney disease and traditionally labelled as renal osteodystrophy. Uremic leontiasis ossea is a rare and severe form of renal osteodystrophy with characteristic overgrowth of the craniofacial bones. Imaging, in particular computed tomography, is valuable for the diagnosis and management of such rare condition. Uremic leontiasis ossea has distinctive imaging features with significant overgrowth of the jaw and characteristic internal serpiginous tunneling. The recognition of its radiological appearance and abrupt management are essential to avoid its devastating esthetic and functional impairments.
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Introduction Hirsutism is defined as a condition in which women develop excessive body hair in androgen-dependent areas, which include lips, chin, chest, abdomen, back, and femoral region. The link between hyperandrogenism and insulin resistance and/or hyperinsulinemia is well established. Polycystic ovary syndrome, as a form of hyperandrogenism, has been linked to several diseases, including type 2 diabetes mellitus and hirsutism. However, it is unknown how common hyperandrogenic problems are in women who receive exogenous insulin. Therefore, this study aims to assess the effect of insulin intake and other sociodemographic factors on the development of hirsutism among diabetic females. Methods This case-control study was conducted in six regions of Saudi Arabia, including Al-Ahsa, Dammam, Qatif, Riyadh, Abha, and Jeddah, during the year 2022. The population was Saudi females who were diabetic, between the age of 18 and 65 years, and living in Saudi Arabia. The sample size was 186 participants. Of the participants, 48 had considerable hirsutism whereas 138 did not. The degree of hirsutism has been determined using the Ferriman and Gallwey scoring tool. Results A total of 186 diabetic females were included in the study. Among the females, 97 (52.2%) were on insulin therapy and 89 (47.8%) were on non-insulin therapies. Only hair distribution on the chin showed a significant difference between the study groups where 4.1% of cases on insulin showed complete cover with light or heavy hair on the chin compared to 3.4% of controls (P = 0.049). There was no significant difference regarding hirsutism score among the study patients according to insulin intake where the mean score was 5.4 ± 5.1 among cases on insulin versus 4.7 ± 5.1 for controls (P = 0.978). Adjusted logistic regression models showed an insignificant association between diabetic female hirsutism and insulin intake (OR = 1.1 and 1.0, respectively; P > 0.05). Conclusion Many factors were examined to reveal their associations with hirsutism in diabetic females. Neither the type of diabetes nor insulin intake was significantly correlated with the development of hirsutism. On the other hand, age was found to be significantly associated with the development of hirsutism among age groups (<30, 30-49, and 50+; P = 0.49). It seemed that the prevalence of hirsutism decreases as age advances.
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PURPOSE: Diabetes is a big public health threat in Saudi Arabia. However, there is limited evidence about dental problems, oral hygiene practices, and dental visits among diabetic patients. The study aimed to evaluate self-perceived oral health status and patterns of dental attendance among diabetic patients in the Eastern province of Saudi Arabia. METHODOLOGY: This cross-sectional study included 486 diabetic patients (mean age 50.14±13.59 years) registered with the Saudi Diabetes Society, Saudi Arabia (October-November 2020). The World Health Organization's oral health questionnaire for adults was administered to collect information about oral health status, oral hygiene practices, and dental attendance, in addition to sociodemographic data. Descriptive and analytical statistics were performed. RESULTS: Most participants (66.3%) reported having dental pain or discomfort during the last year. Bad breath (60.50%), tooth cavities (55.10%), difficulty in biting hard food (55.10%), tooth sensitivity (53.30%), and bleeding gums (52.90%) were common oral problems among participants. More than half the sample (55.1%) reported visiting the dental office during the last year. However, pain or trouble with teeth, gums or mouth was the most common (40.5%) reason for the last dental visit. Only 7.8% of participants visited the dentist for a routine dental check-up. Multiple logistic regression analysis showed that Saudi nationality (AOR 2.68, P 0.008), family history of diabetes (AOR 1.88, P 0.022), and having pain during the last year (AOR 4.01, P <0.001) were the significant factors associated with the last dental visit due to pain. CONCLUSION: This sample of participants demonstrated a high prevalence of dental problems. Few participants performed routine dental visits and most visits were due to pain. Saudis and patients with family history of diabetes and dental pain were more likely to perform pain related dental visits. Multidisciplinary efforts are needed to develop and implement preventive educational and clinical care models for positive oral and general health outcomes.
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Hospital-acquired infections (HAIs) contribute to increased length of hospital stay, higher mortality and higher health-care costs. Prevention and control of HAIs is a critical public health concern. This study assessed the knowledge, attitude, and practice (KAP) of standard infection control precautions among health-care workers (HCWs) in Qassim, Saudi Arabia. A cross-sectional online survey among HCWs was conducted using a structured questionnaire. Predictors of KAP were investigated using multivariate logistic regression analyses and independent sample t-tests. A total of 213 HCWs participated in the survey. The prevalence of good (≥80% correct response) knowledge, attitude, and practice were 67.6%, 61.5%, and 73.2%, respectively. The predictors of good knowledge included the age of the HCWs (>34 years) (adjusted odds ratio: 30.5, p < 0.001), and training (13.3, p < 0.001). More than 6 years of work experience was a significant predictor of having a positive attitude (5.5, p < 0.001). While the predictors of good practice were having >6 years of experience (2.9, p < 0.01), previous exposure to HAIs (2.5, p < 0.05), and training (3.5, p < 0.01). However, being female (0.22, p < 0.001) and older (>34 years) (0.34, p < 0.01) were negatively associated with knowledge. Results indicate that arranging training for HCWs might be useful in improving their knowledge of standard infection control precautions and is also expected to facilitate positive attitude and practice.
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Conhecimentos, Atitudes e Prática em Saúde , Controle de Infecções , Adulto , Estudos Transversais , Feminino , Pessoal de Saúde , Hospitais Universitários , Humanos , Arábia Saudita , Inquéritos e QuestionáriosRESUMO
BACKGROUND: The COVID-19 pandemic has impacted education in myriad ways, primarily leading to an abrupt paradigm shift in teaching and learning practices towards distance learning. The study aims to assess the effectiveness of teaching radiology to undergraduate medical students using synchronous distance learning compared to traditional on-campus learning through exploring students' perceived satisfaction and concerns. Students' perceptions were correlated with their attendance, grades, and frequency of technical difficulties. METHODS: The study was designed as an observational study involving fourth-year medical students (2019/2020) from two institutions. The cohort students were exposed to traditional learning, distance learning, or both. Students completed an online self-administered questionnaire concerning their perceptions of distance learning. Students' attendance, engagement, technical difficulties, and post-clerkship knowledge assessments were analyzed using descriptive and inferential statistics. RESULTS: A total of 145 participants completed the clerkship using the following strategies: traditional learning (n = 66), both traditional and distance learning (n = 67), and distance learning alone (n = 12). The most important result indicates that the abrupt transition to distance learning was well perceived. Most students preferred distance learning over traditional learning in the radiology clerkship (p = .05). During the synchronous sessions, student attendance was high, reaching to 100%. Technical difficulties were limited (1.9%), and they did not affect learning. CONCLUSION: Synchronous distance teaching promotes learning, interaction, and enjoyment in undergraduate radiology education, and it can be as effective as traditional on-campus learning. The technical difficulties encountered, although they were limited, can be overcome by recording the synchronous sessions.
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Metal nanomaterials such as bismuth oxide nanoparticles (Bi2O3NPs) have been extensively used in cosmetics, dental materials, pulp capping, and biomedical imaging. There is little knowledge about the health risk of Bi2O3NPs in humans, which warrants a thorough toxicity investigation of Bi2O3NPs at the cellular level. In this experiment, we investigated the cytotoxic effect of Bi2O3NPs on human breast cancer (MCF-7) cells over 24 and 48 h. MCF-7 cells were exposed to Bi2O3NPs at varying doses (0.1, 0.5, 1.0, 5, 10, 20, 40 µg/mL) for 24 and 48 h. We assessed the toxicity of Bi2O3NPs by measuring its effect on the viability and oxidative stress biomarkers, e.g., GSH, SOD, and catalase in MCF-7 cells. The pro-apoptotic effects of Bi2O3NPs on MCF-7 cells were determined via evaluating dysfunction of mitochondrial membrane potential (MMP), caspase-3 activity, externalization of phosphatidylserine, and chromosome condensation. Furthermore, apoptotic cells were evaluated using 7-AAD fluorescence stain and Annexin V-FITC. Bi2O3NPs induced oxidative stress in MCF-7 cells in a time- and dose-dependent manner. Bi2O3NPs increased the rate of both necrotic cells and apoptotic cells. In addition, the blue fluorescence of MCF-7 cells with condensed chromatin was increased in a time- and dose-dependent manner. In conclusion, the present study highlights the potential toxic effects of Bi2O3NPs at the cellular level and suggests further investigation of Bi2O3NPs before any medical purposes.
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Neoplasias da Mama , Nanopartículas , Apoptose , Bismuto , Humanos , Células MCF-7 , Estresse Oxidativo , Espécies Reativas de OxigênioRESUMO
PURPOSE: Melanotic schwannoma (MS) was formerly known as a rare variant of schwannoma. The behavior of MS is unpredictable, with a tendency for recurrence and metastasis. The purpose of this study was to illustrate the imaging characteristics of these rare and misdiagnosed tumors. The prognosis of MS is discussed, along with the importance of follow-up exams to assess for recurrence and metastasis. Furthermore, we compare our results with those previously published on MS in order to have a better understanding of this rare entity. METHODS: Three MS cases were encountered between 2008 and 2015 at our institute. All available data were reviewed, including the clinical history, imaging findings, operative notes, and the histopathology results. A follow-up magnetic resonance imaging (MRI) scan was also reviewed up to 23 months post surgery to assess for recurrence. RESULTS: Three cases of MS are included: one in the brain and two in the spine. The brain lesion was in the occipital region. The spine lesions were thoracic intramedullary and sacral intradural. All cases were hypointense on T2-weighted imaging. Gross total resection was achieved for all lesions without adjuvant therapy. To date, the brain lesion recurred 15 months after surgery. CONCLUSIONS: MS is a rare and distinct entity rather than a variant of schwannoma, and it poses both diagnostic and management dilemmas. Although MS has characteristic MRI features, including T1 and T2 shortening, the preoperative diagnosis is always challenging. Accurate diagnosis is crucial for management planning, including long-term follow-up exams to assess for recurrence and metastasis.
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Neoplasias Encefálicas/diagnóstico , Melanoma/diagnóstico , Neurilemoma/diagnóstico , Neoplasias da Medula Espinal/diagnóstico , Adulto , Neoplasias Encefálicas/cirurgia , Diagnóstico Diferencial , Feminino , Humanos , Imageamento por Ressonância Magnética , Melanoma/cirurgia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Neurilemoma/cirurgia , Sacro/cirurgia , Neoplasias da Medula Espinal/cirurgia , Vértebras Torácicas/cirurgiaRESUMO
Coconut (Cocos nucifera L.), a member of the palm family (Arecaceae), is one of the most economically important crops in tropics, serving as an important source of food, drink, fuel, medicine, and construction material. Here we report an assembly of the coconut (C. nucifera, Oman local Tall cultivar) mitochondrial (mt) genome based on next-generation sequencing data. This genome, 678,653bp in length and 45.5% in GC content, encodes 72 proteins, 9 pseudogenes, 23 tRNAs, and 3 ribosomal RNAs. Within the assembly, we find that the chloroplast (cp) derived regions account for 5.07% of the total assembly length, including 13 proteins, 2 pseudogenes, and 11 tRNAs. The mt genome has a relatively large fraction of repeat content (17.26%), including both forward (tandem) and inverted (palindromic) repeats. Sequence variation analysis shows that the Ti/Tv ratio of the mt genome is lower as compared to that of the nuclear genome and neutral expectation. By combining public RNA-Seq data for coconut, we identify 734 RNA editing sites supported by at least two datasets. In summary, our data provides the second complete mt genome sequence in the family Arecaceae, essential for further investigations on mitochondrial biology of seed plants.