Teaching Musculoskeletal Module using dissection videos: feedback from medical students.

BACKGROUND AND AIMS: Over the last two decades many medical schools have been exploring alternatives to hands-on cadaver dissection in teaching anatomy. This study aimed at reporting medical students' feedback on using dissection videos in teaching anatomy of the musculoskeletal system. METHODS: Dissection videos were used to teach the anatomy of the musculoskeletal system for third year medical students. At the end of the module, feedbacks from medical students were reported using a questionnaire designed for this purpose. Statistically valid responses were considered for 284 students. RESULTS: Around 60% of the students enjoyed learning anatomy by watching dissection videos but the majority - mostly non-Jordanian - thought that the duration of the videos should be shorter. 83% (236/284)of the students enjoyed the presence of an instructor to guide them through the video and 85% (241/284) wanted to discuss the content with the instructor after watching. Most of the students liked to have access to the videos at any time in an open lab policy. Only 23% (66/284) of the students - mostly Jordanian - were willing to completely replace cadaveric prosections with dissection videos. Most of the students found that dissection videos helped them to understand anatomy lectures in a better way and in memorizing anatomical details. A significantly higher percentage of Jordanian students preferred watching dissection videos at home and preferred dissection videos to replace traditional anatomy lab sessions. CONCLUSIONS: In the light of our present findings, using dissection videos as a teaching method of anatomy was well received by students. However, it seemed that the students wanted dissection videos to be integrated with using cadaveric prosections rather than replacing them.

Targeting DNA Repair Pathways in Hematological Malignancies.

DNA repair plays an essential role in protecting cells that are repeatedly exposed to endogenous or exogenous insults that can induce varying degrees of DNA damage. Any defect in DNA repair mechanisms results in multiple genomic changes that ultimately may result in mutation, tumor growth, and/or cell apoptosis. Furthermore, impaired repair mechanisms can also lead to genomic instability, which can initiate tumorigenesis and development of hematological malignancy. This review discusses recent findings and highlights the importance of DNA repair components and the impact of their aberrations on hematological malignancies.

Branching patterns of the aortic arch: a computed tomography angiography-based study.

PURPOSE: This study aimed to investigate the anatomical variations in direct branches of the aortic arch in Jordanians using the contrast Computed Tomography (CT) imaging techniques and to determine their prevalence according to sex. METHODS: This analytical, retrospective study included 500 patients (209 females, 291 males), who were referred to the Radio-Diagnostic Department at King Abdullah University Hospital for CT angiography of the aortic arch from 2010 to 2014. Patients were selected using a random sampling method. RESULTS: Six patterns of arrangement of arteries according to their origin from the aortic arch were identified in Jordanians. The most common pattern was the normal classical one and accounted for 61.2 % of cases. All other patterns were considered variations and accounted for 38.8 % of cases. Variation patterns were classified into six different types. There was no significant correlation (p > 0.05) between sex and the occurrence of different types of variations. CONCLUSION: This study provides new information regarding the prevalence of aortic arch branching variations in Jordanians. A wide range of anatomical variations in the branching pattern of the aortic arch was observed. This should be taken into consideration during angiography, aortic instrumentation, and supra-aortic thoracic, head, and neck surgery.

Anatomy learning styles and strategies among Jordanian and Malaysian medical students: the impact of culture on learning anatomy.

PURPOSE: The study aims to investigate anatomy learning styles and strategies of Jordanian and Malaysian medical students at the Jordan University of Science and Technology. METHODS: The study is a cross-sectional questionnaire-based study. Students' responses for the questionnaire were numerically coded, and the results were analyzed to reveal statistically significant differences between Jordanian and Malaysian students. RESULTS: The results showed that Jordanian medical students were less interested in using cadavers in learning anatomy than Malaysian medical students. However, similar to their Malaysian counterparts, they prefer to employ other tools to learn anatomy like plastinated models and Internet-based resources. In addition to the aforementioned tools, Malaysian students were more interested in using cross-sectional images and making their own revision cards. Both Jordanian and Malaysian medical students were more interested in learning anatomy through clinical cases, and by system rather than by region. Moreover, it was revealed that Jordanian medical students learn anatomy more efficiently when they formulate a general view of a particular topic. Both Jordanian and Malaysian medical students also relied on reciting definitions and memorizing facts to learn anatomy. The study also reported significant differences between Jordanian and Malaysian students' perspectives on learning anatomy. CONCLUSIONS: The findings of the study suggest that Jordanian and Malaysian medical students posses different cultures of learning. Jordanian anatomy instructors need to consider these different learning cultures when they prepare their instructional methods and teaching materials to fulfill the educational needs of their culturally diverse students.

Pathophysiology of traumatic brain injury.

Traumatic brain injury (TBI) is considered an epidemic that continues to compromise the welfare of humankind. Despite the extensive efforts invested in countering this clinical health problem, current clinical science and technology still fall short of providing a pharmacological cure for TBI rendering tens of thousands of TBI patients vulnerable to its detrimental sequelae. Over the past 30 years, the understanding of the pathophysiological mechanisms of TBI indicates that the pathology of TBI is biphasic. It comprises 2 injuries; the primary and the secondary injuries. The primary injury occurs simultaneously with the impact that caused the injury, which explains why this injury is not amenable to acute intervention. Whereas the secondary injury is a composite of interwoven pathophysiological responses that commence after the initial trauma leading to delayed, non-mechanical impairment of neuronal structure and function. In this review, we aim to highlight the main pathophysiological mechanisms that take place in the primary and secondary phases of traumatic brain injury.

Neuronal Cell Types in the Spinal Trigeminal Nucleus of the Camel Brain.

Neurons in the spinal trigeminal nucleus of a camel were morphologically studied by the Golgi impregnation method. The neurons were classified based on the size and shape of their cell bodies, the density of their dendritic trees, and the morphology and distribution of their appendages. At least 12 morphological types of neurons were found in the camel spinal trigeminal nucleus, including the following: stalked, islets, octopus-like, lobulated, boat-like, pyramidal, multipolar, round, oval, and elongated neurons. These neurons exhibited large numbers of various forms of appendages that arise not only from their dendrites but also from their cell bodies. Moreover, neurons with unique large dilatations especially at their dendritic branching points were also reported. The neurons reported in this study displayed an array of different sizes and shapes and featured various forms of appendages arising from cell bodies and dendrites. Such morphologically distinctive neuronal cell types might indicate an evolutionary adaptation to pain and temperature processing pathways at the level of the spinal trigeminal nucleus in camels, which traditionally live in a very harsh climatic environment and are frequently exposed to painful stimuli.

The attitude and knowledge of pediatricians and family physicians toward COVID-19 vaccination in children: A cross-sectional study.

COVID-19 vaccines to children are expected to reduce the transmission of the disease to high-risk groups and achieve herd immunity in younger populations. A positive attitude toward COVID-19 vaccination in children among healthcare workers (HCWs) is predicted to reduce parents' hesitancy to vaccinate their children. This study aimed to assess the knowledge and attitude of pediatricians and family physicians toward COVID-19 vaccination in children. A total of 112 pediatricians and 96 family physicians (specialists and residents) were interviewed to assess the level of knowledge, attitude, and perceived safety of COVID-19 vaccines for children. Physicians willing to receive regular COVID-19 vaccination (analogous to the influenza vaccine) had significantly higher knowledge and attitude scores (P < .05). Multivariate analysis indicated that a higher knowledge score and having at least five years of experience as a specialist were significantly associated with a positive attitude among pediatricians or family physicians (P < .05). Pfizer/BioNTech was the preferred COVID-19 vaccine in children among physicians of both groups (>67%). Around 71% of physicians believed COVID-19 vaccines for children do not cause or worsen any health condition. Educational and training programs that increase the knowledge of physicians about COVID-19 vaccines and their safety in children are recommended to inform a more positive attitude.

Medical education across three colleges of medicine: perspectives of medical students.

Aim: This study aimed to explore and evaluate various components of the medical education process (lectures, labs, small-group discussions, clinical rotations, and undergraduate research) in three colleges of medicine in Jordan. Methods: This cross-sectional questionnaire-based study included 849 undergraduate students from three main medical colleges in Jordan. Statically valid responses were considered for 684 students. The participants were from Jordan University of Science and Technology, Yarmouk University, and the University of Jordan. Results: The distribution of students according to their admission status was 276 (40%) regular, 266 (38.9%) parallel, and 142 (20.8%) international programs. Personal interest and self-initiation were the major motives for studying medicine in 66.1%. Regarding the frequency of attending classes, University of Jordan students reported the highest rate of regular classes' attendance (93%). The study also reported that lecture notes and textbooks were the main sources of learning for medical students. The study also reported superior academic performance of students in the regular program compared to students in the parallel and international programs. Participants of the study criticized the medical curricula in the three colleges mentioned above because of the lack of active research programs. Most of the students (40%-56%) also complained that the lectures within the modules were not well-integrated, and they felt that the academic environment was moderate (48-59%). In addition, most students in the clinical phase complained of overcrowding in hospital wards during clinical rotation. Conclusions: Based on students' feedback, multiple aspects of the medical education process require substantial reform to meet the expectations of medical students in Jordan.

Evidence on the Heroin-Mediated Impairment of the Oxidative Status of Erythrocytes.

Away from hemorheological properties, the effect of heroin addiction on erythrocytes is poorly investigated. This study aimed to investigate the oxidative impacts of heroin administration on erythrocytes. Study subjects included chronic intravenous heroin addicts and control subjects. Hematological analysis and redox parameters were measured, including serum concentration of methemoglobin ([MethHb]), serum glutathione peroxidase-1 ([GPX-1]), serum glutathione peroxidase (GPX) activity, erythrocytic protein carbonyl content, and oxidized to reduced glutathione (GSSG/GSH) ratio. Hematological analysis revealed that addicts had a significantly higher red cell distribution width, consistent with the mild anisocytosis and poikilocytosis of erythrocytes. As compared to control subjects, significantly higher levels of serum [Met-Hb], [GPX-1], and GPX activity (p < 0.001) were reported among addicted subjects. A significant association between [MetHb] and GPX activity was observed with r = 0.764 (p < 0.001). Furthermore, significantly higher erythrocytic protein carbonyl contents and GSSG/GSH ratio were evident among heroin addicts (p < 0.005) that were significantly associated with r = 0.429 (p=0.01). Results demonstrate preliminary evidence that heroin addiction is implicated in impaired redox status of erythrocytes. Considering the pharmacokinetics of heroin, erythrocytic antioxidant mechanisms, and turnover rate, further investigation is required to evaluate the extent and clinical outcomes, especially upon over-dose administration.

A Golgi study of neurons in the camel cerebellum (Camelus dromedarius).

Neurons in the cerebellar cortex of camels were studied using modified Golgi impregnation methods. Neurons were classified according to their position, morphology of their soma, density and distribution of dendrites, and the course of their axons. Accordingly, eight types of neurons were identified. Three types were found in the molecular layer: upper and lower stellate cells and basket cells, and four types were found in the granular layer: granule cells, Golgi Type II cells, Lugaro cells, and unipolar brush cells. Only the somata of Purkinje cells were found in the Purkinje cell layer. The molecular layer is characterized by the presence of more dendrites, dendritic spines, and transverse fibers. Golgi cells also show extensive dendritic branching and spines. The results illustrate the neuronal features of the camel cerebellum as a large mammal living in harsh environmental conditions. These findings should contribute to advancing our understanding of species-comparative anatomy in achieving better coordination of motor activity.

Pharmacological inhibition of lipid peroxidation attenuates calpain-mediated cytoskeletal degradation after traumatic brain injury.

Free radical-induced lipid peroxidation (LP) is critical in the evolution of secondary injury following traumatic brain injury (TBI). Previous studies in our laboratory demonstrated that U-83836E, a potent LP inhibitor, can reduce post-TBI LP along with an improved maintenance of mouse cortical mitochondrial bioenergetics and calcium (Ca(2+)) buffering following severe (1.0 mm; 3.5 m/s) controlled cortical impact TBI (CCI-TBI). Based upon this preservation of a major Ca(2+) homeostatic mechanism, we have now performed dose-response and therapeutic window analyses of the ability of U-83836E to reduce post-traumatic calpain-mediated cytoskeletal (α-spectrin) proteolysis in ipsilateral cortical homogenates at its 24 h post-TBI peak. In the dose-response analysis, mice were treated with a single i.v. dose of vehicle or U-83836E (0.1, 0.3, 1.3, 3.0, 10.0 or 30.0 mg/kg) at 15 min after injury. U-83836E produced a dose-related attenuation of α-spectrin degradation with the maximal decrease being achieved at 3.0 mg/kg. Next, the therapeutic window was tested by delaying the single 3 mg/kg i.v. dose from 15 min post-injury out to 1, 3, 6 or 12 h. No reduction in α-spectrin degradation was observed when the treatment delay was 1 h or longer. However, in a third experiment, we re-examined the window with repeated U-83836E dosing (3.0 mg/kg i.v. followed by 10 mg/kg i.p. maintenance doses at 1 and 3 h after the initial i.v. dose) which significantly reduced 24 h α-α-spectrin degradation even when treatment initiation was withheld until 12 h post-TBI. These results demonstrate the relationship between post-TBI LP, disruptions in neuronal Ca(2+) homeostasis and calpain-mediated cytoskeletal damage.

Neuronal cell types in the anterior ventral thalamic nucleus of the camel.

The anterior ventral nucleus neurons in of the camel brain were morphologically studied by Golgi impregnation method. Two neuronal types of were found in the camel anterior ventral thalamic nucleus, namely, Golgi-type I neurons and Golgi-type II neurons. Those neurons were generally similar to their counterparts in the human thalamus. The Golgi-type I neurons exhibited medium to large cell body (mean diameter = 25 µm) which was either multipolar or triangular in shape. They had from 3 to 10 primary dendrites with many branches but with no spines or appendages. The Golgi-type II neurons had small to medium size (somatic mean diameter = 17.5 µm), their cell bodies were variable in shape, some were round, and others were multipolar or fusiform. These cells bodies had two to six primary dendrites with few branches that may have spines and/or grape-like appendages. Our findings shed some light on the anterior ventral thalamic nucleus structure of the camel as one of the strongest adaptive mammals to the hard climatic conditions.

Differential response of oxidative and glycolytic skeletal muscle fibers to mesterolone.

Oxidative and glycolytic muscle fibers differ in their ultrastructure, metabolism, and responses to physiological stimuli and pathological insults. We examined whether these fibers respond differentially to exogenous anabolic androgenic steroids (AASs) by comparing morphological and histological changes between the oxidative anterior latissimus dorsi (ALD) and glycolytic pectoralis major (PM) fibers in adult avian muscles. Adult female White Leghorn chickens (Gallus gallus) were randomly divided into five groups: a vehicle control and four mesterolone treatment groups (4, 8, 12, and 16 mg/kg). Mesterolone was administered orally every three days for four weeks. Immunocytochemical techniques and morphometric analyses were employed to measure the changes in muscle weight, fiber size, satellite cell (SC) composition, and number of myonuclei. Mesterolone increased both body and muscle weights and induced hypertrophy in glycolytic PM fibers but not in oxidative ALD fibers. Mesterolone induced SC proliferation in both muscles; however, the myonuclear accretion was noticeable only in the PM muscle. In both muscles, the collective changes maintained a constant myonuclear domain size and the changes were dose independent. In conclusion, mesterolone induced distinct dose-independent effects in avian oxidative and glycolytic skeletal muscle fibers; these findings might be clinically valuable in the treatment of age-related sarcopenia.

Mitochondrial protection after traumatic brain injury by scavenging lipid peroxyl radicals.

Mitochondrial dysfunction after traumatic brain injury (TBI) is manifested by increased levels of oxidative damage, loss of respiratory functions and diminished ability to buffer cytosolic calcium. This study investigated the detrimental effects of lipid peroxyl radicals (LOO(*)) and lipid peroxidation (LP) in brain mitochondria after TBI by examining the protective effects of U-83836E, a potent and selective scavenger of LOO(*) radicals. Male CF1 mice were subjected to severe controlled cortical impact TBI (CCI-TBI) and treated with either vehicle or U-83836E initiated i.v. at 15 min post-injury. Calcium (Ca(++)) buffering capacity and respiratory function were measured in isolated cortical mitochondrial samples taken from the ipsilateral hemisphere at 3 and 12 h post-TBI, respectively. In vehicle-treated injured mice, the cortical mitochondrial Ca(++) buffering capacity was reduced by 60% at 3 h post-injury (p < 0.001) and the respiratory control ratio was decreased by 27% at 12 h post-TBI, relative to sham, non-injured mice. U-83836E treatment significantly (p < 0.05) preserved Ca(++) buffering capacity and attenuated the reduction in respiratory control ratio values. Consistent with the functional effects of U-83836E being as a result of an attenuation of mitochondrial oxidative damage, the compound significantly (p < 0.001) reduced LP-generated 4-hydroxynonenal levels in both cortical homogenates and mitochondria at both 3 and 12 h post-TBI. Unexpectedly, U-83836E also reduced peroxynitrite-generated 3-nitrotyrosine in parallel with the reduction in 4-hydroxynonenal. The results demonstrate that LOO(*) radicals contribute to secondary brain mitochondrial dysfunction after TBI by propagating LP and protein nitrative damage in cellular and mitochondrial membranes.

Using YouTube to Learn Anatomy: Perspectives of Jordanian Medical Students.

PURPOSE: The study is aimed at exploring the popularity, impact, and usefulness of using YouTube in learning anatomy as perceived by Jordanian medical students studying at Jordan University of Science and Technology. METHODS: The present work is a cross-sectional questionnaire-based study. First-, second-, and third-year medical students were invited to complete an anonymous questionnaire. Students' responses were numerically coded, and the results were analyzed to reveal any statistically significant differences related to gender or level of study. RESULTS: The results showed that 96.4% of the students used YouTube in general, 91.2% used it as a source of information, and 83.9% used YouTube as a learning tool in medical school. Further, YouTube was used by 79.1% of the students as an anatomy-learning tool. Most of these students used this platform in learning gross anatomy. The study also revealed that dissection videos were the most viewed anatomy-related content. Regarding the perceived value of YouTube as an anatomy-learning tool, the majority of the students reported that YouTube offered them useful anatomical information and enhanced their understanding, memorization, and recall of anatomical information. In addition, most of them recommended using YouTube as an anatomy-learning tool. Statistical analysis of the results revealed the presence of gender-related significant differences in students' perspectives. Such differences were also found among students of different levels of study. CONCLUSION: Medical students have positive attitudes toward using YouTube in augmenting their anatomy learning. For this, educators are encouraged to adopt YouTube as an educational tool in their anatomy instruction and to create new anatomy-related YouTube videos to enhance their students' learning.

Erratum: Scavenging of lipid peroxyl radicals protects plasma lipids and proteins from peroxynitrite.

[This corrects the article DOI: 10.3892/br.2018.1144.].

Morphometric Analysis of the Corpus Callosum According to Age and Sex in Middle Eastern Arabs: Racial Comparisons and Clinical Correlations to Autism Spectrum Disorder.

This study sought to examine the influence of age and sex on morphometric measurements of the corpus callosum (CC) within Middle Eastern Arab population, in order to obtain reference data and conduct racial comparisons with previously reported measurements from other ethnicities. Furthermore, it aimed to investigate CC variations that may occur in children with autism. To this end, magnetic resonance images of normal brains were acquired from three different age groups, consisting of children, younger adults, and older adults. Brain images were also acquired from boys with autism spectrum disorder (ASD). The CC length, area, and thickness were measured. The CC length was smaller in children than in the other age groups, but no difference in CC length was found between younger and older adults. The CC area and thickness were greater in younger adults than in children and older adults, and greater in older adults than in children. With regard to sexual dimorphism, the CC area and forebrain volume were larger in male children than in female children. No sex-related differences in CC area or thickness were found in adults. However, the ratio of CC area to the forebrain volume was greater in adult females than in males, owing to the smaller forebrain volume in females. The absolute length of the CC was greater in older adult males than in their female counterparts. In addition, significant differences in CC measurements were found in comparison to measurements obtained from other ethnicities. Lastly, significant reductions in CC area and thickness were found in boys with ASD compared to their neurotypical peers. In conclusion, age and sex significantly influence morphometric measurements of CC in Middle Eastern Arab population. This study points to the presence of racial differences in CC size. Finally, it reveals that children with ASD display a distinct reduction in CC size compared to neurotypical children of the same ethnicity.

The desensitization of the transient receptor potential vanilloid 1 by nonpungent agonists and its resensitization by bradykinin.

Transient receptor potential vanilloid type-1 (TRPV1) channels have crucial roles in inflammatory hyperalgesia. Different inflammatory mediators can modulate TRPV1 sensitization. Bradykinin is an algogenic substance released at the site of inflammation. The aim of the present study is to investigate the desensitization of TRPV1 receptor by nonpungent agonists and to determine how bradykinin and prostaglandin E2 receptors (EP3 and EP4) modulate the resensitization of TRPV1 receptor after being desensitized by nonpungent agonists. Tail flick test was used to investigate capsaicin-induced thermal hyperalgesia and the desensitization of TRPV1 by the nonpungent agonists (olvanil and arvanil) in male BALB/c mice weighed (22-25 g). Resensitization of TRPV1 by bradykinin and the role of prostaglandin receptors in mediating sensitization of TRPV1 were also investigated. Intraplantar injection of capsaicin (0.3 µg) produced a robust thermal hyperalgesia in mice, while olvanil (0.3 µg) or arvanil (0.3 µg) produced no hyperalgesia, emphasizing their lack of pungency. Olvanil and arvanil significantly attenuated capsaicin-induced thermal hyperalgesia in mice. Bradykinin significantly reversed the desensitizing effects of arvanil, but not olvanil. EP4 but not EP3 receptors mediate the sensitization of TRPV1 By bradykinin in vivo. The present study provides evidence for a novel signaling pathway through which bradykinin can regulate the TRPV1 ion channel function via EP4 receptor.

Erratum: Effect of progesterone on nitric oxide/cyclic guanosine monophosphate signaling and contraction in gastric smooth muscle cells.

[This corrects the article DOI: 10.3892/br.2018.1161.].