SARS-CoV-2 outbreak: role of viral proteins and genomic diversity in virus infection and COVID-19 progression.

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection is the cause of coronavirus disease 2019 (COVID-19); a severe respiratory distress that has emerged from the city of Wuhan, Hubei province, China during December 2019. COVID-19 is currently the major global health problem and the disease has now spread to most countries in the world. COVID-19 has profoundly impacted human health and activities worldwide. Genetic mutation is one of the essential characteristics of viruses. They do so to adapt to their host or to move to another one. Viral genetic mutations have a high potentiality to impact human health as these mutations grant viruses unique unpredicted characteristics. The difficulty in predicting viral genetic mutations is a significant obstacle in the field. Evidence indicates that SARS-CoV-2 has a variety of genetic mutations and genomic diversity with obvious clinical consequences and implications. In this review, we comprehensively summarized and discussed the currently available knowledge regarding SARS-CoV-2 outbreaks with a fundamental focus on the role of the viral proteins and their mutations in viral infection and COVID-19 progression. We also summarized the clinical implications of SARS-CoV-2 variants and how they affect the disease severity and hinder vaccine development. Finally, we provided a massive phylogenetic analysis of the spike gene of 214 SARS-CoV-2 isolates from different geographical regions all over the world and their associated clinical implications.

Application of supraclavicular island flap in oral and maxillofacial reconstruction.

Several surgical modalities are available for maxillofacial reconstruction as locoregional or microvascular free flaps. PURPOSE: (a) Evaluate the reliability of the supraclavicular flap in cervico-orofacial region; (b) investigate the role of computed tomography angiography (CTA) in predicting the post-operative viability of the flap; (c) assess the speech, feeding, and esthetics after reconstruction using this flap. METHODS: Eleven patients included in this study underwent either conventional or delayed harvesting of the supraclavicular flap (SCF). All the patients had diagnostic computed tomography angiography (CTA) of the supraclavicular flap before the surgery. RESULTS: The mean harvesting time of the flap was 45.45 ± 4.16 min. The average length of the flap was 22.64 ± 1.12 cm, whereas the mean width of the flap was 6.14 ± 1.14 cm. The flap survived in 9 patients, while two patients had complete flap loss. After the surgery, three patients complained of speech difficulties. Two patients had swallowing problems. After the surgery, three patients complained of speech difficulties. Two patients had swallowing problems. Only two patients complained of weakness in the donor site. None of the patients reported that the weakness or pain at the donor site affected their daily activities or quality of life. CONCLUSION: The pedicled SCF represents a safe and feasible option that can be used to reconstruct a wide array of maxillofacial oncologic defects. However, a study with a larger sample size is recommended to achieve more reliable clinical results for the modified delayed technique modification in terms of their effect on the survival of the supraclavicular flap.

Potential of La-Doped SrTiO3 Thin Films Grown by Metal-Organic Vapor Phase Epitaxy for Thermoelectric Applications.

La-doped SrTiO3 thin films with high structural quality were homoepitaxially grown by the metal-organic vapor phase epitaxy (MOVPE) technique. Thermogravimetric characterization of the metal-organic precursors determines suitable flash evaporator temperatures for transferring the liquid source materials in the gas phase of the reactor chamber. An adjustment of the charge carrier concentration in the films, which is necessary for optimizing the thermoelectric power factor, was performed by introducing a defined amount of the metal-organic compound La(tmhd)3 and tetraglyme to the liquid precursor solution. X-ray diffraction and atomic force microscopy verified the occurrence of the pure perovskite phase exhibiting a high structural quality for all La concentrations. The electrical conductivity of the films obtained from Hall-effect measurements increases linearly with the La concentration in the gas phase, which is attributed to the incorporation of La3+ ions on the Sr2+ perovskite sites by substitution inferred from photoemission spectroscopy. The resulting structural defects were discussed concerning the formation of occasional Ruddlesden-Popper-like defects. The thermoelectric properties determined by Seebeck measurements demonstrate the high potential of SrTiO3 thin films grown by MOVPE for thermoelectric applications.

Intrusion Detection System Based on Pattern Recognition.

Artificial intelligence has been developed to be able to solve difficult problems that involve huge amounts of data and that require rapid decision-making in most branches of science and business. Machine learning is one of the most prominent areas of artificial intelligence, which has been used heavily in the last two decades in the field of network security, especially in Intrusion Detection Systems (IDS). Pattern recognition is a machine learning method applied in medical applications, image processing, and video processing. In this article, two layers' IDS is proposed. The first layer classifies the network connection according to the used service. Then, a minimum number of features that optimize the detection accuracy of malicious activities on that service are identified. Using those features, the second layer classifies each network connection as an attack or normal activity based on the pattern recognition method. In the training phase, two multivariate normal statistical models are created: the normal behavior model and the attack behavior model. In the testing and running phases, a maximum likelihood estimation function is used to classify a network connection into attack or normal activity using the two multivariate normal statistical models. The experimental results prove that the proposed IDS has superiority over related IDSs for network intrusion detection. Using only four features, it successfully achieves DR of 97.5%, 0.001 FAR, MCC 95.7%, and 99.8% overall accuracy.

Added value of dynamic 3T-MRI to conventional static MRI in evaluation of internal derangement of tempromandibular joint.

PURPOSE: This prospective study aimed at comparing dynamic T1W fast field echo sequence to the standard static sequences in the evaluation of TMJ disorders using 3T MRI. METHODS: 8 patients, 14 with bilateral symptomatic internal derangement of TMJ and 4 with unilateral symptoms (32 TMJs) were examined, including 17 females and one male. Static T1W, T2W and PD turbo spin-echo sequences in closed and open mouth positions as well as dynamic T1W-FFE sequence were acquired on 3T MRI unit and images were assessed for the articular disc position, morphological disc changes, condylar morphology and translation. Marginal homogeneity test was used to analyze difference between dynamic and static imaging findings and significant results were considered at p ≤ 0.05. RESULTS: The study shows statistically significant difference between static and dynamic MRI in the evaluation of condylar position (p < 0.005). Out of the examined 32 joints, 28 joints (87.5%) had normal condylar position and 4 joints (12.5%) had a subluxated condyle. Dynamic MRI showed 24 joints (75%) had normal condylar position and 8 joints (25%) had a subluxated condyle. Regarding disc morphology and position, dynamic MRI added no significant superior information compared to standard static images. CONCLUSION: Static MRI of TMJ provides proper accurate assessment of pathological changes in TMJ disorders and considered the gold standard. Dynamic MRI added superior information regarding joint biomechanics even in normal static MRI cases and valuable findings regarding the movement patterns of the condyle and disc in different types of TMJ internal derangement.

Association between genetic variations of mitochondrial isocitrate dehydrogenase (IDH2) and acute myocardial infarction.

PURPOSE: Mitochondrial isocitrate dehydrogenase (IDH2) is a major contributor to cellular redox control. The aim of this study was to preliminary link IDH2 genetic variations to redox imbalance, atherogenesis and risk of acute myocardial infarction (AMI). METHODS: This case-control study included 120 AMI patients and 120 healthy controls. IDH2 genetic variations were tested using direct sequencing. IDH2 enzyme activity was measured spectrophotometrically. Malondialdehyde (MDA) and Oxidized low density lipoproteins (ox-LDL) concentrations, as biomarkers of oxidative stress, were quantitated using ELISA. RESULTS: Four missense heterozygous mutations were detected within IDH2 gene. The variant forms of the enzyme showed a markedly reduced enzymatic activity (2.22 ± 0.56 mU/mL in wild type compared to 0.65 ± 0.35 mU/mL in mutant enzyme). IDH2 enzyme activity correlated negatively with MDA and ox-LDL concentrations (r = -80.875 and -0.891 respectively). There was a strong association between IDH2 mutations and elevated MDA and ox-LDL (rpb = 0.764 and 0.652, both p < 0.001). After adjustment of other risk factors, IDH2 genetic variations showed to be an independent risk factor for AMI (ß=1.792, p = 0.019). CONCLUSIONS: The study proved that IDH2 genetic variations lead to impaired enzyme activity, redox imbalance, accumulation of lipid-peroxides and coronary atherogenesis. However, because such gene association has not been studied before, further studies are recommended.

The interplay between atrial fibrillation and acute myocardial infarction.

Atrial fibrillation is the most frequently occurring supraventricular arrhythmia in patients presenting with acute myocardial infarction. It is associated with worse outcomes when it coexists with acute myocardial infarction and results in increased morbidity and mortality. Both conditions are closely related to each other and share similar pathophysiological pathways. The management of atrial fibrillation in patients with acute myocardial infarction is challenging since triple antithrombotic therapy is indicated, but this results in a markedly increased risk of bleeding events and mortality. This review addresses the interactions between both conditions including common risk factors, possible mechanisms through which acute myocardial infarction contributes to development of atrial fibrillation and vice versa, and the problem of using anticoagulation in the management of these patients.

Virtual Reality in the Neurosciences: Current Practice and Future Directions.

Virtual reality has made numerous advancements in recent years and is used with increasing frequency for education, diversion, and distraction. Beginning several years ago as a device that produced an image with only a few pixels, virtual reality is now able to generate detailed, three-dimensional, and interactive images. Furthermore, these images can be used to provide quantitative data when acting as a simulator or a rehabilitation device. In this article, we aim to draw attention to these areas, as well as highlight the current settings in which virtual reality (VR) is being actively studied and implemented within the field of neurosurgery and the neurosciences. Additionally, we discuss the current limitations of the applications of virtual reality within various settings. This article includes areas in which virtual reality has been used in applications both inside and outside of the operating room, such as pain control, patient education and counseling, and rehabilitation. Virtual reality's utility in neurosurgery and the neurosciences is widely growing, and its use is quickly becoming an integral part of patient care, surgical training, operative planning, navigation, and rehabilitation.

Ángulo de bifurcación corregido versus ángulo de bifurcación distal para la predicción de la rama lateral. Compromiso después de la bifurcación provisional Intervención Coronaria / Corrected Bifurcation Angle versus Distal Bifurcation Angle for Prediction of Side Branch Compromise after Provisional Bifurcation Coronary Intervention

Provisional bifurcation percutaneous coronary intervention (PCI) is recommended over two stent strategy but with the risk of side branch (SB) compromise. Prediction SB compromise is crucial for optimizing of the procedure outcome. Neglecting the proximal bifurcation angle (BA), the distal BA was presented as a reliable predictor of SB compromise supposing that the main vessel is always a straight vessel. However, its impact on the fate of side branch is debated. This study aims to compare between of the corrected BA, the sum of proximal and distal BAs, and the distal BA in terms of prediction of SB compromise. This prospective cohort study was conducted in Zagazig university hospitals in the duration between March 2019 and March 2020, and involved 185 patients who underwent provisional bifurcation PCI. Patients were divided according to the corrected BA into two groups; straight bifurcation model group which involved 73 patients with corrected BA = 180º, and wide bifurcation model group which involved 112 patients with corrected BA > 180 º. Compared to the wide bifurcation model, the incidence of SB compromise was substantially higher in the straight bifurcation model (52.1% vs. 15.2%; P < 0.001). The corrected BA had a better area under the curve compared to the distal BA with statistically significant difference (0.711 vs. 0.580; P = 0.023). Multivariate analysis demonstrated that the corrected BA was among the independent predictors of SB compromise. The study concluded that the corrected BA could be a novel strong predictor of SB compromise after provisional bifurcation PCI for future verification.