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1.
Ann Med Surg (Lond) ; 86(10): 6159-6163, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39359794

RESUMO

Introduction and importance: Spontaneous coronary artery dissection (SCAD) is a rare but potentially fatal condition, often underdiagnosed despite its significance in acute coronary syndrome (ACS). The true prevalence remains uncertain due to diagnostic challenges. Identifying SCAD cases is crucial for reducing mortality and morbidity, especially considering the recurrence risk. The authors present two cases highlighting the importance of multimodality imaging in diagnosing and managing SCAD. Case presentation: Case 1: A 53-year-old man with a history of brain aneurysm presented with chest pain and shortness of breath. Despite negative EKGs and stress tests, coronary computed tomography angiography (CCTA) revealed non-obstructive dissection flaps. Medical management improved his condition.Case 2: A 55-year-old woman with no significant medical history experienced recurrent chest pain. Initial tests were negative, but CCTA revealed SCAD. Further screening uncovered undiagnosed fibromuscular dysplasia. Clinical discussion: SCAD poses diagnostic challenges, often mimicking other cardiac conditions. Traditional tests may yield negative results, necessitating advanced imaging techniques like CCTA. Recognizing SCAD's association with connective tissue disorders (CTD) is vital for comprehensive patient care. The authors' cases emphasize the importance of a systematic approach to diagnosing chest pain, including noninvasive modalities and considering underlying etiologies. Conclusion: SCAD diagnosis requires a high index of suspicion, especially when traditional cardiac tests are inconclusive. Beyond treatment, patients should undergo further evaluation for CTDs, particularly in those with minimal risk factors for atherosclerosis. Increased awareness and a multimodal diagnostic approach are crucial for timely intervention and improved outcomes in SCAD patients. Learning objectives: The authors aim to increase awareness regarding different clinical presentations of SCAD to decrease the risk of missed or late diagnosis. The authors' case series also signifies the multimodal imaging approach's role in evaluating chest pain. Upon diagnosis of SCAD, it is imperative to go beyond treatment and implement a reverse algorithmic strategy to discover any underlying causes and risk factors for SCAD predisposition.

2.
Obes Rev ; : e13838, 2024 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-39289905

RESUMO

INTRODUCTION: Obesity is characterized by chronic low-grade inflammation. This study presents an updated systematic review and meta-analysis on the effect of caloric restriction (CR) and intermittent fasting (IF) on plasma inflammatory biomarkers (C-reactive protein [CRP], tumor necrosis factor [TNF]-alpha, and interleukin [IL]-6) in individuals with obesity/overweight compared with unrestricted or ad libitum feeding. METHODS: PubMed, Web of Science, and SCOPUS databases were searched for randomized controlled trials (RCTs) reporting inflammatory biomarkers after at least 8 weeks of intervention. Standardized mean differences (SMDs) were calculated using a fixed effect model. Heterogeneity was determined using I2 statistics. Sensitivity analysis was conducted using the "leave-one-out" approach. RESULTS: Relatively few RCTs have investigated the effect of IF on inflammatory biomarkers than with CR (6 vs. 15). Analysis of pooled data showed that CR was associated with a significant reduction in CRP with low heterogeneity (SMD -0.15 mg/L [95% CI -0.30 to -0.00], p = 0.04; I2 = 0%, p = 0.69) and IL-6 with high heterogeneity (SMD -0.31 pg/mL [95% CI -0.51 to -0.10], p = 0.004; I2 = 73%, p = 0.001). IF was associated with a significant decrease in TNF-alpha with moderate heterogeneity (SMD -0.32 pg/mL [95% CI -0.63 to -0.02], p = 0.04; I2 = 44%, p = 0.13). No associations were detected between IF and CRP or IL-6 and CR and TNF-alpha. CONCLUSION: CR may be more effective in reducing chronic low-grade inflammation than IF. However, there were some concerns regarding the included studies' randomization and allocation sequence concealment process.

3.
J Family Community Med ; 31(3): 265-271, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39176019

RESUMO

BACKGROUND: Several universities switched back to face-to-face teaching in 2022 after 2 years of online classes during the coronavirus disease 2019 (COVID-19) crisis. There is no data from these students/teachers on the challenges in postpandemic face-to-face teaching and learning. The current study's aim was to identify the challenges of face-to-face teaching and learning postpandemic from the perspective of students and instructors. MATERIALS AND METHODS: Undergraduate medical students (n = 210) registered in Imam Abdulrahman Bin Faisal University and instructors (n = 72) filled out online questionnaires from November 2022 to March 2023 on teaching-learning challenges in the postpandemic period. The questionnaires asked students about their interest in education, scores, degree of shyness, how clear the voices of the instructors wearing face masks were, fear of COVID-19, preferred mode of teaching, and advantages/disadvantages of face-to-face teaching. Descriptive statistics included frequencies and percentages for qualitative variables; Chi-square test was applied to assess association between categorical variables. RESULTS: Students reported a decrease in their educational interest postpandemic (47.1%), diffidence in interaction (42.4%), blurred teachers' voices because of the face masks (63.3%), and lack of teachers' empathy (47.6%). There was a significant association between preclinical year students and a decrease in educational interest (P = 0.002), diffidence in class interactions (P = 0.001), and fear of contracting COVID-19 infection while interacting with teachers (P = 0.04). Instructors complained of a decrease in students' interest in education (65.3%), especially the instructors of the clinical years (16.7% vs. 2.1%; P = 0.022). About 10% students reported taking leave from university on purpose due to fear of contracting COVID-19 infection; students and instructors both supported lecture recordings (98.6% and 63.9%, respectively). The students' and instructors' preferred platform for learning was "hybrid" (80.5% and 63.9%, respectively). CONCLUSION: Challenges faced by the students include decreased interest in learning, drop in scores, muffled voices because of the face masks, increased shyness, waste of time in commutes, lack of flexibility in schedules, increased workload, and fear of catching COVID-19 infection. There is strong support for hybrid/blended learning and recording lectures.

4.
J Family Community Med ; 31(3): 214-221, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39176014

RESUMO

BACKGROUND: Composite Autonomic Symptom Score-31 (COMPASS-31) is an easy-to-use screening tool for the evaluation of autonomic dysfunction in various diseases affecting neural function but has rarely been used in the assessment of long coronavirus disease 2019 (COVID-19). This study aimed to evaluate the diagnostic accuracy of the COMPASS-31 score in detecting dysfunction of the autonomic nervous system in patients 3 months after COVID-19 infection. MATERIALS AND METHODS: Fifty-nine subjects were recruited and grouped into 2: (a) controls (n = 31) who had never had positive polymerase chain reaction results for COVID-19 before and (b) the post-COVID-19 patients (n = 28) who had confirmed COVID-19 infection 3-6 months before recruitment. COMPASS-31 questionnaire was utilized to evaluate subjective symptoms or evidence of autonomic dysfunction. Autonomic dysfunction was assessed objectively by cardiovascular autonomic reflex tests (CARTs) and heart rate variability (HRV). For comparison of quantitative variables between two groups, t-test or Mann-Whitney U test, as appropriate, were used. Sensitivity, specificity, negative predictive value (NPV), positive predictive value (PPV), negative likelihood ratio (LR), and positive LR were used as measures of diagnostic accuracy. Receiver operating characteristic (ROC) curve analysis determined the overall accuracy of COMPASS-31. RESULTS: The median COMPASS score was found to be significantly higher in post-COVID-19 participants than controls (15.5 vs. 10, P = 0.021). The median total CART score was also significantly higher in post-COVID-19 participants (0 vs. 1, P < 0.001). Out of 6 domains of the COMPASS score, the median value for orthostatic dysfunction was found to be significantly higher in post-COVID-19 participants than controls (12 vs. 0, P = 0.008). There was significantly fair accuracy of the COMPASS score with an area under the receiver operating curve 0.68 (0.54-0.82) following the total CART score ≥2 as the gold standard in the diagnosis of autonomic dysfunction (P = 0.021). The best cutoff point of the total COMPASS score was 12.5, where the optimal values of sensitivity, specificity, and positive and negative predictive values were achieved. Nonsignificant and weak correlations between CARTs, HRV parameters, and COMPASS score were found. CONCLUSION: COMPASS-31 could be used as a user-friendly screening tool to detect autonomic dysfunction in post-COVID-19 cases with acceptable sensitivity and specificity.

5.
J Vasc Surg Cases Innov Tech ; 10(4): 101541, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38994220

RESUMO

Spontaneous spinal epidural hematoma (SSEH) is a rare condition, and it usually presents with acute onset neck or back pain, progressive weakness, and other symptoms of spinal cord compression. Catheter-directed thrombolysis is one option for limbs threatened by iliofemoral venous thrombosis; other options, such as venous thrombectomy (either open or percutaneous), are also available. There are few reported cases of SSEH owing to catheter-directed thrombolysis for deep venous thrombosis (DVT). We present a case of a 65-year-old man who presented with left lower limb extensive iliofemoral DVT and received catheter-directed thrombolysis. The patient initially had rapid improvement in his symptoms with restoration of limb perfusion. However, within 6 hours of starting catheter-directed thrombolysis, the patient developed extensive SSEH and underwent emergent spinal decompression surgery with laminectomy of T11 to T12 with complete resolution of the neurological deficit. Clinicians should consider SSEH in differential diagnosis if the patient develops acute onset neck or back pain after catheter-guided thrombolysis for DVT.

6.
Am J Case Rep ; 25: e944173, 2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39058665

RESUMO

BACKGROUND Despite having many benefits, frequently-used medications may still have potential risks and can cause harm. Hemopericardium is a lethal pathology with a high risk of mortality and a lower differential diagnosis consideration. When adding both mentioned elements, their consideration as a differential diagnosis would require a higher threshold. This report presents a 66-year-old man with atrial fibrillation, heart failure, and aortic stenosis status post transcatheter aortic valve replacement (TAVR) 1 year ago with hemopericardium while treated with apixaban. CASE REPORT We present the case of a 66-year-old man with multiple medical conditions, including atrial fibrillation, heart failure, and aortic stenosis post-transcatheter aortic valve replacement 1 year before admission, who presented with 2 weeks of dyspnea and lower-limb swelling. Initial assessments revealed atrial fibrillation, elevated brain natriuretic peptide, and a chest X-ray indicating possible left pleural effusion and cardiomegaly. On day 4, an echocardiogram identified a large hemopericardium and tamponade, prompting urgent surgery. A pericardial window was performed, draining 1700 cc of bloody fluid. The postoperative improvement included normalized hemodynamics and echocardiographic findings. Pathology confirmed hemopericardium. The follow-up echocardiogram showed improved cardiac function, and the patient was transferred to the general medical floor. CONCLUSIONS This case sheds light on the uncommon but critical complications associated with direct oral anticoagulant therapy. With only a handful of reported cases, the rarity of this condition underscores the need for heightened awareness among clinicians. The patient's intricate medical history accentuates the challenges in managing anticoagulation in individuals with multiple comorbidities.


Assuntos
Estenose da Valva Aórtica , Inibidores do Fator Xa , Derrame Pericárdico , Pirazóis , Piridonas , Substituição da Valva Aórtica Transcateter , Humanos , Piridonas/efeitos adversos , Piridonas/uso terapêutico , Masculino , Idoso , Derrame Pericárdico/induzido quimicamente , Derrame Pericárdico/etiologia , Derrame Pericárdico/diagnóstico , Pirazóis/efeitos adversos , Pirazóis/uso terapêutico , Inibidores do Fator Xa/efeitos adversos , Inibidores do Fator Xa/uso terapêutico , Estenose da Valva Aórtica/cirurgia , Substituição da Valva Aórtica Transcateter/efeitos adversos , Fibrilação Atrial/tratamento farmacológico , Complicações Pós-Operatórias/diagnóstico , Ecocardiografia
7.
Cureus ; 16(5): e59885, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38854363

RESUMO

We present a rare and complex case of a 76-year-old male patient with a history of low-grade neuroendocrine tumor (NET) of the small intestine, status post resection, who presented with recurrence of the tumor in the liver and subsequent carcinoid heart syndrome (CHS). The recurrent liver tumor caused severe tricuspid regurgitation and CHS, highlighting the rare association between NETs and CHS, particularly in the elderly population. This case underscores the importance of multidisciplinary care and close monitoring for patients with recurrent NETs and potential cardiac complications.

8.
Cureus ; 16(5): e59648, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38832147

RESUMO

Staphylococcus lugdunensis is a gram-positive, coagulase-negative organism, typically found in the normal skin flora, predominantly colonizing the perineal region. It has gained recognition as an opportunistic pathogen capable of causing severe infections. This manuscript presents a case study of a 75-year-old female with multiple comorbidities, including hypertension, hyperlipidemia, atrial fibrillation on Xarelto, type 2 diabetes mellitus, hypothyroidism, and a bioprosthetic aortic valve. The patient exhibited symptoms of fever, chills, and lethargy following a dog scratch that resulted in wounds on the left lower extremity. Despite initial negative findings in the drug screen and unremarkable workup for other infectious etiologies, the patient's clinical course revealed the presence of S. lugdunensis in the blood cultures. Timely intervention with broad-spectrum intravenous antibiotics and a six-week course of cefazolin led to significant improvement without recurrence. Staphylococcus lugdunensis, previously considered a relatively benign microorganism, has become a significant player in infectious diseases, particularly causing skin and soft tissue infections and infective endocarditis (IE). It is considered an aggressive pathogen, especially in chronic immunocompromised personnel, with a high potential for morbidity and mortality. S. lugdunensis was found to be the fourth most common cause of IE. The manuscript discusses the epidemiology, clinical presentation, and management of S. lugdunensis infections, emphasizing the importance of early recognition and treatment to prevent potentially fatal outcomes.

9.
Cureus ; 16(4): e58380, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38756297

RESUMO

Pharmacomechanical therapy and catheter-directed thrombolysis are potent treatments for venous thromboembolism. However, limited data exist regarding the management of thrombi in the inferior vena cava (IVC). IVC thrombus resulting from tumors is a particularly uncommon condition. Managing IVC tumor thrombi poses even greater challenges, as conventional therapies such as systemic anticoagulation and thrombolysis are often ineffective. In this report, we present the case of a 73-year-old male with an inferior vena cava tumor thrombus successfully managed through aspiration thrombectomy utilizing the Inari FlowTriever system.

10.
Global Spine J ; : 21925682241251764, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695328

RESUMO

STUDY DESIGN: Cross sectional comparative study. OBJECTIVES: The current study aims to explore the calcification potential (BMP2 expression) of intervertebral discs and its association with the presence of vertebral endplate defects visible on MRI. METHODS: Forty-seven herniated lumbar disc samples obtained from patients aged 20-76 (31 M/16F) undergoing surgery. Five-µm thin sections were stained with H&E in order to assign a histological degeneration score (HDS) from 0-15 on the basis of cell density (0-5), structural alterations (0-4), granular changes (0-3) and mucus degeneration (0-3). Sections were immuno-stained with anti BMP-2 antibodies to observe the calcification potential in these discs. In addition, pre-operativeT2-T1 W MRI images of the lumbar spine were analyzed for the presence and type (typical or atypical) of vertebral endplate defects, grade of disc degeneration (Pfirrmann grade I-V), presence of high intensity zones (HIZ), and Modic changes at the operated level. RESULTS: Vertebral endplate defects, Modic changes & HIZ were observed in 81%, 29% and 21% of patients respectively. Mean HDS & BMP-2 expression was 9 ± 2 and mean 71 ± 36 spots/mm2 respectively. Discs with adjacent vertebral endplate defects showed increased cell density (P = .004), mucus degeneration (P = .002), HDS (P = .01) and BMP-2 expression (P = .01). Discs with HIZ also had increased HDS, but significance was seen with increased BMP2 expression (P = .006). HDS showed a positive correlation with BMP 2 expression (r = .30, P = .04). CONCLUSION: These findings suggest that the altered mechanical environment of discs is strongly associated with BMP-2 expression which is an important marker of intervertebral disc calcification.

11.
Cureus ; 16(2): e54179, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38496114

RESUMO

This case report details the challenging presentation of a 68-year-old patient of cardio-circulatory collapse with pericardial effusion and recurrent pleural effusions. Hypotension did not respond to conventional intensive care measures. Despite comprehensive investigations, the underlying cause remained unidentified until intravenous thiamine replacement therapy was administered, restoring normotension and preventing pericardial or pleural effusion recurrence. The case underscores the importance of early recognition of thiamine deficiency in patients with pericardial and pleural effusions or critical illness, emphasizing the need to expand vigilance for thiamine deficiency and consider replacement therapy without a definitive diagnosis.

12.
PeerJ Comput Sci ; 10: e1827, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38435622

RESUMO

This study aims to investigate the problem of concept drift in cloud computing and emphasizes the importance of early detection for enabling optimum resource utilization and offering an effective solution. The analysis includes synthetic and real-world cloud datasets, stressing the need for appropriate drift detectors tailored to the cloud domain. A modified version of Long Short-Term Memory (LSTM) called the LSTM Drift Detector (LSTMDD) is proposed and compared with other top drift detection techniques using prediction error as the primary evaluation metric. LSTMDD is optimized to improve performance in detecting anomalies in non-Gaussian distributed cloud environments. The experiments show that LSTMDD outperforms other methods for gradual and sudden drift in the cloud domain. The findings suggest that machine learning techniques such as LSTMDD could be a promising approach to addressing the problem of concept drift in cloud computing, leading to more efficient resource allocation and improved performance.

13.
Cureus ; 16(2): e53967, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38469010

RESUMO

We present a case of a 30-year-old male who was admitted with Streptococcus pneumoniae meningitis. He initially responded well to antibiotic therapy. However, the patient later developed symptomatic sinus bradycardia, which was likely due to intracranial hypertension. Even though the patient showed overt symptoms, vigilant monitoring, interdisciplinary collaboration, and cardiac evaluation helped avoid unnecessary interventions. This case highlights the importance of recognizing and managing rare cardiac complications associated with central nervous system infections.

14.
J Family Community Med ; 31(1): 71-78, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38406218

RESUMO

BACKGROUND: Reports indicate that there are menstrual cycle disturbances following coronavirus disease 2019 (COVID-19) vaccination. The present study explored the prevalence of menstrual irregularities after COVID-19 vaccination and the association of menstrual irregularities with vaccine type, doses, immediate adverse effects, history of COVID-19 infection, and its severity. MATERIALS AND METHODS: For this cross-sectional study, 406 women of reproductive age completed an online survey about the postvaccine changes in their menstruation (cycle duration, bleeding days, and bleeding amount), COVID-19 vaccine history (doses, type of vaccine, and immediate adverse effects), history of COVID-19 infection, and its severity. Data was analyzed using SPSS; descriptive statistics were computed and Chi-square test, and binary logistic regression analysis were performed. RESULTS: Of the total 406 women, 45% reported postvaccine changes in their menstrual cycle. The most common menstrual change was increased dysmenorrhea (68%), followed by an increase in the length of the cycle (52%). There was a significant association between postvaccine menstrual changes and the age, marital status, and family history of menstrual irregularities. No association was observed between postvaccine menstrual changes and COVID-19 vaccine-and COVID-19 infection-related variables. As per the best-fit model of our predictors, the odds of having postvaccine menstrual changes were 0.41 times less in "single" women (confidence interval [CI] = 0.26-0.27; P < 0.001) and 1.714 times greater in women who had a "family history of menstrual irregularities" (CI = 1.092-2.690; P = 0.02), respectively. CONCLUSION: A substantial number of women complained of postvaccine menstrual changes regardless of their age, type of COVID-19 vaccine, doses, immediate adverse effects, and COVID-19 infection history/severity. Being "single" decreased the probability, whereas having a family history of menstrual irregularities increased the probability significantly of having postvaccine menstrual changes.

15.
J Orthop Res ; 42(5): 1104-1110, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37975261

RESUMO

Adjacent segment degeneration is commonly observed in patients after fusion surgery. Among the associated risk factors is the preoperative presence of adjacent disc degeneration (ADD). The risk factors and other spine phenotypes associated with preoperative ADD is critical to understand the pathological process and better prognosis postsurgery. Current study aims to assess and compare the magnetic resonance imaging (MRI) spinal phenotype of herniated level with and without ADD. Preoperative T2W sagittal lumbar MRI images of 155 lumbar disc herniated patients were analyzed for the presence of ADD (Pfirrmann grade III and above). The herniated disc level was assessed for the presence and absence of vertebral endplate (VEP) defects, Modic changes, and high intensity zone (HIZ). Mean age of patients was 38 ± 2 years, almost 62% were males. ADD was found in 57%, VEP defects were seen in 62% of the herniated level, 24.5% showed Modic changes, 3.8% showed spondylolishthesis, and 15.5% revealed HIZ. Age and other demographic factors did not have any significant effect on the presence of ADD, the patients with extruded and sequestered discs had more ADD (p = 0.02). VEP defects were significantly higher in levels with ADD (p = 0.02). Patients with ADD had significantly VEP defect scores (p = 0.01), Modic score (p = 0.002), HIZ score (0.02), and posterior bulge score (p < 0.001). Findings suggest that affected levels with VEP defects and severe grade of disc herniation have the greater likelihood of having ADD. Once developed this ADD may also affect the other spinal levels, and also can affect postoperative prognosis.


Assuntos
Degeneração do Disco Intervertebral , Deslocamento do Disco Intervertebral , Disco Intervertebral , Masculino , Humanos , Adulto , Feminino , Degeneração do Disco Intervertebral/patologia , Deslocamento do Disco Intervertebral/complicações , Deslocamento do Disco Intervertebral/diagnóstico por imagem , Deslocamento do Disco Intervertebral/patologia , Vértebras Lombares/cirurgia , Fenótipo , Imageamento por Ressonância Magnética/métodos , Disco Intervertebral/patologia
17.
Sci Rep ; 13(1): 11571, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37463960

RESUMO

Due to the significance of trust in Social Internet of Things (SIoT)-based smart marketplaces, several research have focused on trust-related challenges. Trust is necessary for a smooth connection, secure systems, and dependable services during trade operations. Recent SIoT-based trust assessment approaches attempt to solve smart marketplace trust evaluation difficulties by using a variety of direct and indirect trust evaluation techniques and other local trust rating procedures. Nevertheless, these methodologies render trust assessment very sensitive to seller dishonesty, and a dishonest seller may influence local trust scores and at the same time pose a significant trust related threats in the system. In this article, a MarketTrust model is introduced, which is a blockchain-based method for assessing trust in an IoT-based smart marketplace. It has three parts: familiarity, personal interactions, and public perception. A conceptual model, assessment technique, and a global trust evaluation system for merging the three components of a trust value are presented and discussed. Several experiments were conducted to assess the model's security, viability, and efficacy. According to results, the MarketTrust model scored a 21.99% higher trust score and a 47.698% lower average latency than both benchmark models. Therefore, this illustrates that using the proposed framework, a potential buyer can efficiently choose a competent and trustworthy resource seller in a smart marketplace and significantly reduce malicious behavior.

18.
Entropy (Basel) ; 25(5)2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37238542

RESUMO

Image encryption techniques protect private images from unauthorized access while they are being transmitted. Previously used confusion and diffusion processes are risky and time-consuming. Therefore, finding a solution to this problem has become necessary. In this paper, we propose a new image encryption scheme that combines the Intertwining Logistic Map (ILM) and Orbital Shift Pixels Shuffling Method (OSPSM). The proposed encryption scheme applies a technique for confusion inspired by the rotation of planets around their orbits. We linked the technique of changing the positions of planets around their orbits with the shuffling technique of pixels and combined it with chaotic sequences to disrupt the pixel positions of the plain image. First, randomly selected pixels from the outermost orbit are rotated to shift the pixels in that orbit, causing all pixels in that orbit to change their original position. This process is repeated for each orbit until all pixels have been shifted. This way, all pixels are randomly scrambled on their orbits. Later on, the scrambled pixels are converted into a 1D long vector. The cyclic shuffling is applied using the key generated by the ILM to a 1D long vector and reshaped into a 2D matrix. Then, the scrambled pixels are converted into a 1D long vector to apply cyclic shuffle using the key generated by the ILM. After that, the 1D long vector is converted into a 2D matrix. For the diffusion process, using ILM generates a mask image, which is then XORed with the transformed 2D matrix. Finally, a highly secure and unrecognizable ciphertext image is obtained. Experimental results, simulation analysis, security evaluation, and comparison with existing image encryption schemes show that it has a strong advantage in defending against common attacks, and the operating speed of this encryption scheme also performs excellently in practical image encryption applications.

19.
Postgrad Med J ; 99(1175): 1020-1026, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-36882000

RESUMO

STUDY PURPOSE: Multiple assessment tools are used to assess future doctors' knowledge, clinical skills, and professional attitudes. In the present research, the difficulty level and discriminating ability of different types of written and performance-based assessments designed to measure the knowledge and competency of medical students were compared. METHODS: The assessment data of 2nd & 3rd-year medical students (the academic year 2020-2021) in the College of Medicine at Imam Abdulrahman Bin Faisal University (IAU) were retrospectively reviewed. Based on end-of-the-year overall grades, students were divided into high and low scorers. Both groups were compared by independent sample t-test for their mean scores achieved in each type of assessment. Difficulty level and discriminating ability of the assessments were also explored. MS Excel and Statistical Package for Social Sciences (SPSS version 27) were used for analysis. Area under the curve was calculated through ROC analysis. A p-value <0.05 was believed significant. RESULTS: In each type of written assessment, the high scorer group achieved significantly higher scores compared to the low scorers. Among performance-based assignments (except the PBLs), scores did not differ significantly between high and low scorers. The difficulty level of performance-based assessments was "easy" whereas it was "moderate" for written assessments (except the OSCE). The discriminating ability of performance-based assessments was "poor" whereas it was "moderate/excellent" for written assessments (except the OSCE). CONCLUSION: Our study results indicate that written assessments have excellent discriminatory ability. However, performance-based assessments are not as difficult and discriminatory as written assessments. The PBLs are relatively discriminatory among all performance-based assessments. Key messages What is already known on this topic At Imam Abdulrahman Bin Faisal University, written and performance-based assessments both are graded on criterion-referenced scales. The student's grades at the end of the year are an aggregate of his/her scores in written and performance-based assessments. What this study adds Our study results show that performance-based assessments are not as difficult and discriminatory in differentiating between high and low scorers as written assessments. How this study might affect research, practice or policy Performance-based assessments should be made a hurdle exam (pass or fail) for the students to move to the next level, or students must pass each assessment component (written and performance-based) separately.


Assuntos
Clero , Estudantes de Medicina , Humanos , Masculino , Feminino , Estudos Retrospectivos , Arábia Saudita , Universidades
20.
Vasc Health Risk Manag ; 19: 1-11, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36647392

RESUMO

Background: Obesity is a global pandemic that is associated with high morbidity and mortality. Natural herbs are commonly used for weight reduction and appetite suppression. Therefore, we aim to investigate the role and mechanism of Nigella sativa (NS) and ginger on weight reduction and appetite regulation. Methods: This experimental study was performed at Imam Abdulrahman Bin Faisal University. Twenty-five female rats were distributed into 5 groups: NS (oral 1000mg/kg), Ginger (500 mg/kg), NS-ginger (both interventions), a positive control (intraperitoneal 50 µg/kg Liraglutide), and a negative control. Each intervention was given for 9 weeks. Food intake and body weight were assessed weekly. Serum lipid profile and peptides involved in appetite control (cholecystokinin (CCK), glucagon-like peptide 1(GLP-1), gastric inhibitory polypeptide (GIP), ghrelin, peptide YY, and orexin) were assayed at the end of the experiment. Results: None of the interventions showed a statistically significant difference regarding food consumption or weight gain (p > 0.05). However, the three interventions significantly reduced total cholesterol (TC), NS and NS-ginger significantly increased HDL, NS increased ghrelin and ginger increased orexin. Conclusion: The present dose and duration of NS, ginger, or in combination did not demonstrate a significant change in body weight or food consumption in comparison to the negative or positive controls. However, NS or ginger has improved the lipid profile by reducing TC and increasing HDL. In addition, NS or ginger can influence some of the peptides involved in appetite regulation such as the increase in ghrelin induced by NS and the reduction of orexin induced by ginger. We believe that these latter effects are novel and might indicate a promising effect of these natural products on appetite regulation.


Assuntos
Depressores do Apetite , Nigella sativa , Zingiber officinale , Animais , Feminino , Ratos , Apetite , Depressores do Apetite/farmacologia , Peso Corporal , Grelina/farmacologia , Peptídeo 1 Semelhante ao Glucagon/farmacologia , Lipídeos , Orexinas/farmacologia , Ratos Wistar , Redução de Peso
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