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.

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.

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.

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.

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.

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.

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.

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.

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.

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.].

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.].

Erratum: Gender differences in the regulation of MLC20 phosphorylation and smooth muscle contraction in rat stomach.

[This corrects the article DOI: 10.3892/br.2018.1053.].

Changes in Gastric Smooth Muscle Cell Contraction during Pregnancy: Effect of Estrogen.

It is well known that pregnancy is associated with frequent gastrointestinal (GI) disorders and symptoms. Moreover, previous reports have shown that estrogen, which changes in levels during pregnancy, participates in the regulation of GI motility and is involved in the pathogenesis of various functional disorders in the stomach. The aim of the current study was to explore the changes in the expression of estrogen receptors (ERs) and examine the effect of estrogen on nitric oxide- (NO-) cyclic guanosine monophosphate (cGMP) pathway and thus relaxation in gastric smooth muscle cells (GSMC) during pregnancy. Single GSMC from early-pregnant and late-pregnant Sprague-Dawley rats were used. Protein and mRNA expression levels of ERs were measured via specifically designed enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR), respectively. NO and cGMP levels were measured via specifically designed ELISA kits. Effect of estrogen on acetylcholine- (ACh-) induced contraction of single GSMC was measured via scanning micrometry in the presence or absence of the NO synthase inhibitor, N-nitro-L-arginine (L-NNA), or guanylyl cyclase inhibitor, 1H-[1,2,4]oxadiazolo[4,3,-a]quinoxalin-1-one (ODQ). Estrogen increased both NO and cGMP levels and their levels were greater in early compared to late pregnancy. Expression of ERs was greater in early compared to late pregnancy. ACh induced greater contraction of GSMC in late pregnancy compared to early pregnancy. Estrogen inhibited ACh-induced contraction in both periods of pregnancy. Importantly, pretreatment of GSMC with either L-NNA or ODQ abolished estrogen inhibitory action on muscle contraction. In conclusion, GSMC contractile behavior undergoes drastic changes in response to estrogen during pregnancy and this might explain some of the pregnancy-associated gastric disorders.

Morphometric Study of the Hard Palate and Its Relevance to Dental and Forensic Sciences.

This study was conducted to identify the morphometric features of the hard palate and to test the reliability of using palatal morphology in sex determination. Three hundred maxillary casts were collected from dental clinics in north Jordan. The age and gender of the patient and the serial number for each cast were recorded. The age range was 6 to 50 years old. A caliper was used to perform the following measurements: the length, width, and depth of the hard palate. In addition, the size, shape, and position of the incisive papilla were also determined. All measurements were done by a trained examiner who was able to perform the measurements in a reproducible manner. Statistical analysis showed that the mean palatal length, width, and depth, and size of dental papilla in both groups were the highest in males. The full logistic regression model including all the three predictors (length, width, and depth) indicated that the three parameters were significantly correlated with gender in the adult group. However, in the child group, only width and length were significantly (p=0.001, p > 0.042 respectively) correlated with gender. Regarding the shape and size of the incisive papilla, they were significantly different between males and females in both adult (p > 0.03) and child (p=0.001) groups. These findings might be potentially relevant to anthropological studies aiming at individual and/or sex identification. Moreover, the results might have clinical value in prosthodontics, especially in fabricating complete maxillary dentures for edentulous patients.

The role of transient receptor potential vanilloid receptor 1 and peroxisome proliferator-activated receptors-α in mediating the antinociceptive effects of palmitoylethanolamine in rats.

Palmitoylethanolamine (PEA) is a ligand at peroxisome proliferator-activated receptors-α (PPARα), a nuclear receptor that has anti-inflammatory effects. Herein, complete Freund's adjuvant (CFA)-induced inflammatory pain model in rats and in-vitro calcium imaging studies were used to evaluate the mechanisms that underlie the antinociceptive effects of PEA, including modulating the activity of the transient receptor potential vanilloid receptor 1, which is a key receptor involved in the development of inflammatory pain. Adult male Sprague-Dawley rats (180-250 g) received subcutaneous injections of CFA (0.1 ml) into the plantar surface of the left hind paw. Von Frey filaments were used to determine the paw withdrawal threshold. PEA (50 µg), WY14643 (50 µg, a selective PPARα agonist) were injected into the plantar surface of the left hind paw at day 7 after CFA injection, and behavioral tests were repeated 6 h after drug administration. Rats were killed and dorsal root ganglia neurons were dissected and prepared for calcium imaging. Neurons were loaded with the calcium-sensitive ratiometric dye Fura-2AM. Changes in [Ca]i were measured as ratios of peak florescence at excitation wavelengths of 340 and 380 nm and expressed as a percentage of the KCl (60 mM) response. Both PEA and WY14643 significantly restored the paw withdrawal threshold in a PPARα-dependent fashion (P<0.01). Capsaicin of 15 nM produced 63.9±13.4% of KCl response. Preincubation of dorsal root ganglia neurons with PEA 6 h before stimulation with capsaicin, significantly reduce capsaicin-evoked calcium responses (42.9±6.4% of KCl response, n=54, P<0.001). In conclusion, modulating transient receptor potential vanilloid receptor 1 activity could provide the mechanism that underlies PEA antinociceptive effects observed in vivo.

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

Previous studies have shown that progesterone could inhibit muscle contraction in various sites of the gastrointestinal tract. The underlying mechanisms responsible for these inhibitory effects of progesterone are not fully known. The aim of the current study was to investigate the effect of progesterone on the nitric oxide (NO)/cyclic guanosine monophosphate (cGMP) pathway and muscle contraction in the stomach. Single gastric smooth muscle cells from female Sprague-Dawley rats were used. The expression of progesterone receptor (PR) mRNA was analyzed by reverse transcription polymerase chain reaction. NO and cGMP levels were measured via specific ELISAs. Acetylcholine (ACh)-induced contraction of single gastric muscle cells preincubated with progesterone was measured via scanning micrometry in the presence or absence of the NO synthase inhibitor, Nω-Nitro-L-arginine (L-NNA), or guanylyl cyclase inhibitor, 1H-[1,2,4]Oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), and expressed as percent shortening from resting cell length. PR expression was detected in the stomach muscle cells. Progesterone inhibited ACh-induced gastric muscle cell contraction. Furthermore, progesterone increased NO and cGMP levels in single gastric muscle cells. Most notably, pre-incubation of muscle cells with either L-NNA or ODQ abolished the inhibitory action of progesterone on muscle contraction. These present observations suggest that progesterone promotes muscle cell relaxation in the stomach potentially via the NO/cGMP pathway.

Perspectives and attitudes of Jordanian medical and paramedical students toward surrogate pregnancy.

PURPOSE: This study aims at investigating the perspectives of Jordanian medical and paramedical students on surrogate pregnancy. METHODS: A questionnaire-based cross-sectional study design was used. The sample consisted of n=328 students of both genders. The questionnaire responses were numerically coded and analyzed across gender and the level of education. RESULTS: Approximately, 18% of the students reported good awareness about the ethical dilemmas of surrogacy. The results showed a general reluctance to accept surrogate pregnancy as the majority (80.5% of male students and 97.6% of female students) had a negative attitude toward surrogacy. In addition, undergraduate students were less supportive to surrogate pregnancy than graduate students. Religious considerations were the main reason (accounts for about 70%) for driving negative attitude toward surrogacy. CONCLUSION: The findings of the study indicate a general reluctance toward accepting the concept of surrogate pregnancy, which is mainly due to religious reasons.