225 research outputs found
Autosomal recessive ichthyosis with limb reduction defect: A simple association and not CHILD syndrome
Ichthyosis is a genetically and phenotypically heterogeneous disease that can be isolated and restricted to the skin manifestations or associated with extracutaneous symptoms. One of which is limb reduction defect known as CHILD syndrome; a rare inborn error of metabolism of cholesterol biosynthesis that is usually restricted to one side of the body. Here we describe an Egyptian child with generalized lamellar ichthyosis and limb reduction defect. Most probably this is a simple association and not a rare case of CHILD syndrome with bilateral skin involvement.Keywords: Ichthyosis; Limb reduction; CHILD; Autosomal recessiv
Simulated and experimental approaches to the development of novel test phantoms for radiofrequency heating of implanted medical devices
Magnetic resonance imaging (MRI) has cemented itself as the gold standard for imaging of soft tissues and is only increasing in popularity. Given the rising number of MRI scanners and medical device being implanted into patients, it is becoming increasingly likely that patients undergoing MRI will have an implanted medical device (IMD). The presence of an elongated metallic IMD inside a scanner could result in dangerous interactions with the radiofrequency fields during MRI, thus some of these IMDs preclude the patients from being scanned.
Orthopedic devices typically fall into this category due to their high potential for RF induced heating, and typically perform poorly in the current standard test method for RF heating. That said, there exists a subset of orthopedic IMDs that still ‘fail’ the current safety testing by heating slightly above the current acceptance criterion. It is hypothesized that such IMDs are not truly a hazard to the patient but are likely failing due to the conservative nature of the current RF heating test (ASTM F2182-19a).
In this thesis, novel test platforms are presented for more realistic evaluation of RF heating in orthopedic IMDs, which were used to experimentally challenge the behavior of their simulated counterparts. These test platforms were designed to address the simplifications in the current ASTM test standard that led to exaggerated heating compared to what is expected in patients, namely geometry/material mimicking and perfusion cooling. Heating of a sample implant was simulated (Sim4Life) in these novel test platforms, along with experimental verification of two phantoms to determine agreement with simulation.
Simulations (and experimental work) indicated that IMD heating in these realistic phantoms could be anywhere from 20-50% lower than the current ASTM phantom, which is a reasonable estimate of the magnitude of the safety margin involved. It appears perfusion cooling is most effective at reducing IMD heating (compared to geometry/tissue mimicking differences), though improved experimental verification is required before these simulations can influence regulatory change. Introducing empirical evidence of perfusion cooling to regulatory conversations around implant safety would improve access to MRI for the millions living with such marginally unacceptable orthopedics
Radiological evaluation of postoperative complications after non-sleeve gastrectomy bariatric procedures
Background: Obesity is a medical condition, which may lead to serious related diseases, ultimately, resulting in many morbidities and early mortality. Its management involves many approaches of which bariatric surgery is considered nowadays as one of the most effective treatment for it. However, follow up of postoperative complications of this surgery by effective radiological method as computed tomography (CT) is important for assessment of its success.Objective: The aim of this study was to illuminate the radiological signs and features of postoperative complications after non sleeve bariatric procedures and stressing the importance of using multi-slice CT (MSCT), and fluoroscopic study for detection of these complications. Patients and methods: An observational cohort study for 275 patients with suspected complications after non sleeve gastrectomy bariatric procedures, including 195 patients after Roux-en-Y gastric bypass (RYGB), 76 patients after laparoscopic adjustable gastric banding (LAGB) and 4 patients after intragastric balloon placement was done. These patients were subjected to either multi-slice CT and or fluoroscopy. Results: We detected complications in 21 patients out of the 195 patients who underwent RYGB: leakage, abscess, intestinal obstruction, internal hernia, port site ventral hernia, intussusception, fistula between the gastric pouch and the excluded stomach and hiatus hernia. On the other hand, 8 out of 76 patients operated by LAGB developed complications: band slippage, band erosion, pouch dilatation and tubal disconnection. Lastly two out of the 4 patients who placed intra-gastric balloon encountered other complications: gastric outlet obstruction, spontaneous balloon deflation and distal migration with intestinal obstruction.Conclusion: It could be concluded that bariatric procedures may be followed by many complications and accurate diagnosis of these problems by proper radiological procedures as MSCT is imperative
Oral misoprostol solution in comparison to vaginal misoprostol for induction of labour in a randomized controlled trial
Background: With more than 15% of all gravid women requiring prostaglandins in cervical ripening and labour induction. However, evidence is not clear about the preferred route or dose of the drug. So, this study was designed with objectives to compare the induction delivery interval and safety of titrated oral misoprostol solution with vaginal misoprostol for labour induction in term primigravida women.Methods: This randomized controlled clinical trial was conducted on a total of 100 patients randomly selected among primigravida at term women undergoing induction of labour for obstetric or medical indication for labour induction in Ain Shams University Maternity Hospital. They were divided into two Groups: Group I: patients undergoing induction of labour using misoprostol oral solution and Group II: patients undergoing induction of labour using vaginal misoprostol.Results: Oral misoprostol solution has less induction delivery duration and less side effects than vaginal misoprostol. The induction-delivery time with the oral route compared to the vaginal one (15.2 versus 20.3 hours respectively) with significant p-value (<0.001).Conclusions: Titrated oral misoprostol is safe and effective for labour induction in primigravida patients with unfavorable cervix
Deep Convolutional Neural Networks for Accurate Diagnosis of COVID-19 Patients Using Chest X-Ray Image Databases from Italy, Canada, and the USA
Introduction: Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), famously known as COVID-19, has quickly become a global pandemic. Chest X-ray (CXR) imaging has proven reliable, fast, and cost-effective for identifying COVID-19 infections, which proceeds to display atypical unilateral patchy infiltration in the lungs like typical pneumonia. We employed the deep convolutional neural network (DCNN) ResNet-34 to detect and classify CXR images from patients with COVID-19 and Viral Pneumonia and Normal Controls.
Methods: We created a single database containing 781 source CXR images from four different international sub-databases: the Società Italiana di Radiologia Medica e Interventistica (SIRM), the GitHub Database, the Radiology Society of North America (RSNA), and the Kaggle Chest X-ray Database for COVID-19 (n = 240), Viral Pneumonia (n = 274), and Normal Controls (n = 267). Images were resized, normalized, without any augmentation, and arranged in m batches of 16 images before supervised training, testing, and cross-validation of the DCNN classifier.
Results: The ResNet-34 had a diagnostic accuracy as of the receiver operating characteristic (ROC) curves of the true-positive rate versus the false-positive rate with the area under the curve (AUC) of 1.00, 0.99, and 0.99, for COVID-19 and Viral Pneumonia patient and Normal control CXR images; respectively. This accuracy implied identical high sensitivity and specificity values of 100, 99, and 99% for the three groups, respectively. ResNet-34 achieved a success rate of 100%, 99.6%, and 98.9% for classifying CXR images of the three groups, with an overall accuracy of 99.5% for the testing subset for diagnosis/prognosis.
Conclusions: Based on this high classification precision, we believe the output activation map of the final layer of the ResNet-34 is a powerful tool for the accurate diagnosis of COVID-19 infection from CXR images
Asthma remodeling: The pathogenic role of matrix metalloproteinase-9
AbstractBackgroundAsthma is an airway inflammatory disease with functional and structural changes, leading to bronchial hyperresponsiveness and airflow obstruction. Pathological repair of the airways leads to these structural changes referred as airway remodeling. Matrix metalloproteinases (MMPs) are extracellular degrading enzymes that play a critical role in the remodeling process.Aim of the studyIs to study matrix metalloproteinase-9 in asthmatic patients, detecting its pathogenic role in airway remodeling.Subjects and methodsSamples of broncho-alveolar lavage (BAL) fluid and bronchoscopic biopsies from 30 asthmatic patients (10 mild, 10 moderate and 10 severe) and 10 healthy volunteers were assessed for the levels of matrix metalloproteinase-9 (MMP-9) total and differential cell count (in BAL fluid), histological airway remodeling changes and immunohistochemical expression of MMP-9 (in mucosal biopsies).ResultsBAL and tissue MMP-9 (going hand in hand with airway remodeling changes) were higher in asthmatic patients and it was significantly increased with increased severity. BAL total cell count is higher in asthmatic patients. BAL eosinophils, neutrophils, lymphocytes as well as MMP-9 positive cell count were higher in asthmatic patients and increased with severity. MMP-9 tissue expression was also strongly inversely correlated with the spirometric parameters in asthmatic patients.ConclusionsMMP-9 plays a role in airway inflammation and airway remodeling in asthma. MMP-9 is an important player in airway remodeling in bronchial asthma and may be the link between inflammation and remodeling processes
Underdetermined DOA Estimation Using MVDR-Weighted LASSO
The direction of arrival (DOA) estimation problem is formulated in a compressive sensing (CS) framework, and an extended array aperture is presented to increase the number of degrees of freedom of the array. The ordinary least square adaptable least absolute shrinkage and selection operator (OLS A-LASSO) is applied for the first time for DOA estimation. Furthermore, a new LASSO algorithm, the minimum variance distortionless response (MVDR) A-LASSO, which solves the DOA problem in the CS framework, is presented. The proposed algorithm does not depend on the singular value decomposition nor on the orthogonality of the signal and the noise subspaces. Hence, the DOA estimation can be done without a priori knowledge of the number of sources. The proposed algorithm can estimate up to ((M2−2)/2+M−1)/2 sources using M sensors without any constraints or assumptions about the nature of the signal sources. Furthermore, the proposed algorithm exhibits performance that is superior compared to that of the classical DOA estimation methods, especially for low signal to noise ratios (SNR), spatially-closed sources and coherent scenarios
Relevance of anatomy to medical education and clinical practice: perspectives of medical students, clinicians, and educators
Introduction: Against a backdrop of ever-changing diagnostic and treatment modalities, stakeholder perceptions (medical students, clinicians, anatomy educators) are crucial for the design of an anatomy curriculum which fulfils the criteria required for safe medical practice. This study compared perceptions of students, practising clinicians, and anatomy educators with respect to the relevance of anatomy education to medicine. Methods: A quantitative survey was administered to undergraduate entry (n = 352) and graduate entry students (n = 219) at two Irish medical schools, recently graduated Irish clinicians (n = 146), and anatomy educators based in Irish and British medical schools (n = 30). Areas addressed included the association of anatomy with medical education and clinical practice, mode of instruction, and curriculum duration. Results: Graduate-entry students were less likely to associate anatomy with the development of professionalism, teamwork skills, or improved awareness of ethics in medicine. Clinicians highlighted the challenge of tailoring anatomy education to increase student readiness to function effectively in a clinical role. Anatomy educators indicated dissatisfaction with the time available for anatomy within medical curricula, and were equivocal about whether curriculum content should be responsive to societal feedback. Conclusions: The group differences identified in the current study highlight areas and requirements which medical education curriculum developers should be sensitive to when designing anatomy courses
Modeling and Analysis of Magnetic Nanoparticles Injection in Water-Oil Two-Phase Flow in Porous Media under Magnetic Field Effect
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