Best practices for effective implementation of online teaching and learning in medical and health professions education: during COVID-19 and beyond.

The COVID-19 pandemic has caused worldwide disruption to the entire educational system, including medical and health professions education. Considering the critical situation due to COVID-19, academic institutions shifted the entire pedagogical approach to the virtual learning mode. While delivering online teaching, educators experienced numerous challenges, including access to the internet, poor connectivity, and other technical issues. Some students did not have laptops and necessary devices to attend the Class. Besides, many educators were not confident enough to manage the online mode of delivery. In this perspective, we reviewed the evidence of best practices for the medical and health professions educators to deliver the curriculum through an online platform. Therefore, the current study aimed to review the best practices for effective online teaching and learning in medical and health professions education during COVID-19 and beyond. We reviewed the technical aspects of online teaching and educational strategies required for educators to provide quality training not just during the pandemic but beyond this crisis. The online literature search was performed on Medline, PubMed and google scholar databases for studies on online teaching in medical and health profession education and what are the best practices of teaching globally Online teaching and assessment must balance the requirements of technology, learning outcomes, delivery modes, learning resources, and learning resources. The study concludes that medical and health professions institutions strengthen technical infrastructure, promote continuous faculty development programs, and support indigent students to access digital technology.

Anatomic variations of the human falx cerebelli and its association with occipital venous sinuses.

PURPOSE: Human falx cerebelli is an important anatomical structure in regard to its relations with venous structures during infratentorial approach to reach cerebellar tumors, vascular malformations, traumatic hemorrhage and Chiari malformations. The present study aim to describe the different types of variations of the falx cerebelli, its morphological features and its association with occipital venous sinuses. METHOD: In this study 49 dura mater was obtained from the Institution of Forensic Medicine. The length, width and the depth of the falx cerebelli were measured using a digital compass. The data obtained were statistically analyzed in relation to age and gender. The relations of the falx cerebelli with the occipital sinus was documented. Histological sections from the falx cerebelli were stained with Hematoxylin Eosin to evaluate the fine structure. RESULTS: Among the 49 falx cerebelli examined 36 (73.5%) were classified as normal. The average length, width and depth of the normal falx cerebelli was 3.7, 1.0 and 0.4 cm respectively. Of the 49 falx cerebelli in 1 (2%) case it was absent, in 5 cases (10.2%) duplicate, in 5 cases (10.2%) triplicate, in 1 (2%) case quadruplets and in 1 case (2%) it was five-folded. The proximal and the distal attachments of the falx cerebelli showed 3 types of variations; both attachments triangular, the proximal attachments triangular and the distal ramified and distal attachments triangular and the proximal attachments ramified. The drainage of the occipital sinus of falx cerebelli with variations were evaluated. The increased number of falx cerebelli highly corresponded with the increased number of occipital sinus. CONCLUSIONS: The dural-venous variation in the posterior cranial fossa can be problematic in various diagnostic and operative procedures of this region. Neurosurgeons should be aware of such variations, as these could be potential sources of haemorrhage during the midline suboccipital and infratentorial approaches.

Assessment of the corticospinal fiber integrity in mirror movement disorder.

Mirror movements are unintended movements occurring on one side of the body that mirror the contralateral voluntary ones. It has been proposed that mirror movements occur due to abnormal decussation of the corticospinal pathways. Using detailed multidisciplinary approach, we aimed to enlighten the detailed mechanism underlying the mirror movements in a case subject who is diagnosed with mirror movements of the hands and we compared the findings with the unaffected control subjects. To evaluate the characteristics of mirror movements, we used several techniques including whole exome sequencing, computed tomography, diffusion tensor imaging and transcranial magnetic stimulation. Computed tomography showed the absence of a spinous process of C5, fusion of the body of C5-C6 vertebrae, hypoplastic dens and platybasia of the posterior cranial fossa. A syrinx cavity was present between levels C3-C4 of the spinal cord. Diffusion tensor imaging of the corticospinal fibers showed disorganization and minimal decussations at the lower medulla oblongata. Transcranial magnetic stimulation showed that motor commands were distributed to the motor neuron pools on the left and right sides of the spinal cord via fast-conducting corticospinal tract fibers. Moreover, a heterozygous missense variation in the deleted in colorectal carcinoma gene has been observed. Developmental absence of the axonal guidance molecules or their receptors may result in abnormalities in the leading of the corticospinal fibers. Clinical evaluations and basic neuroscience techniques, in this case, provide information for this rare disease and contribute to our understanding of the normal physiology of bimanual coordination.

Mucociliary transport and histopathological changes in rotation flaps of the nasal mucosa.

Normal mucociliary transport in the mucoperichondrium of the nasal septum is from a distal (anterior) to proximal (posterior) direction. This study was to determine the direction of mucociliary transport and histopathological changes in nasal mucosal rotation flaps when their transport directions were anatomically reversed. Thirty-two rabbits were divided into four groups. Surgical septal rotational flaps were prepared in the experimental groups. Group I was the control group. The distal aspect of the flap was sutured through a large septal window to the other side of the nasal septum, thus changing the direction of the flap. Evaluation was performed 1 week, 1 month and 9 months later with each of these groups named as groups II, III, and IV, respectively. The rate and direction of the mucociliary transport was determined and histopathological investigations were performed from the flaps. The direction of mucociliary transport was observed to continue as distal to proximal direction in the rotated segments. The mucociliary transport rate was found to be decreased in group II, nearly normal in group III, and in normal limits in group IV after surgery. Intense inflammation and decreased number of cilia were present in group II. The inflammation was milder in group III and the epithelium was found to be nearly normal in group IV. The originally programmed direction of mucociliary transport in the nasal rotation flaps is maintained and is not altered or reprogrammed. Histopathological changes revert back to normal from an inflammatory state to reach pre-surgical status over time.

Chronic moderate alcohol consumption induces iNOS expression in the penis: An immunohistochemical study.

AIM: To investigate the effect of moderate alcohol consumption on metabolic alterations, inducible nitric oxide synthase (iNOS), immunohistochemical distribution, and morphological damage to penile erectile tissue in rats. MATERIALS AND METHODS: Male Wistar albino rats were divided into 2 groups. Group 1 rats (control group, n = 8) received tap water ad libitum, and group 2 rats (n = 8) were fed with 20% ethanol. Increasing levels of alcohol were given to the rats over 12 weeks. Immunohistochemistry was then performed using the avidin-biotin-peroxidase technique on 5-pm thickness tissue sections. Stained sections were examined by imaging microscope. RESULTS: Alcohol consumption resulted in a significant increase in iNOS immunoreactivity in the penile erectile tissue. Increased iNOS expression was determined in the tunica albuginea, cavernosal smooth muscle cells, trabeculae of connective tissue, arterioles, and the urethral epithelium. Moreover, chronic alcohol consumption resulted in decreasing serum testosterone and high density lipoprotein (HDL) levels with increasing cholesterol and triglyceride levels. CONCLUSION: Chronic moderate alcohol consumption can affect penile erectile tissue by increasing iNOS immunoreactivity and induce histopathological damage such as penile fibrosis. These abnormalities are also related to the defense mechanism against morphological damage.

Comparison of conventional and no-touch techniques in harvesting saphenous vein for coronary artery bypass grafting in view of endothelial damage.

BACKGROUND: Optimization of saphenous vein patency for myocardial revascularization. OBJECTIVE: The goal of this study was to present the no-touch technique of saphenous vein preparation. This technique consists of harvesting the vein with a pedicle of surrounding tissue, which protects the vein from distension pressure. METHODS: We performed a prospective, randomized study that compared 2 techniques for harvesting saphenous vein-conventional and no-touchin 40 patients undergoing coronary artery bypass grafting. We carried out a morphologic study of the endothelium with the aid of light and transmission electron microscopy and an immunohistochemical assessment to identify adenosine, inducible nitric oxide synthase (iNOS), and vascular endothelial growth factor (VEGF) in the vein wall. RESULTS: The integrity of endothelial cell and all vascular layers was maintained better with the no-touch technique than with the conventional procedure. The immunohistochemical assessment revealed that adenosine receptor, iNOS, and VEGF immunoexpression levels were normal or lower in the no-touch group than in the conventional-harvest group, as shown by the staining densities in all layers of the vein wall. CONCLUSION: Endothelial integrity and adenosine, iNOS, and VEGF immunoreactivities were better preserved when the no-touch technique was used for vein graft harvesting. The mechanical protection provided by the cushion of surrounding tissue in the no-touch group and the vasorelaxation and thromboresistant activities of nitric oxide may be responsible for the reduction in vasospasms and the improved patency rate.

Effects of thoracic epidural anesthesia on flow and endothelium of internal thoracic artery in coronary artery bypass graft surgery.

OBJECTIVES: The internal thoracic artery (ITA) is the preferred conduit for coronary artery bypass graft (CABG) surgery. The authors investigated whether thoracic epidural anesthesia (TEA) as an adjunct to general anesthesia (GA) can increase the blood flow of the ITA. DESIGN: A prospective randomized study. SETTING: A university hospital. PARTICIPANTS: Patients with ischemic heart disease. INTERVENTIONS: Thirty patients scheduled for elective CABG surgery were randomized to receive either GA (n = 15) or GA + TEA (n = 15) after receiving institutional review board approval. Demographics showed similarity between the groups. The epidural catheter was inserted in the thoracic region between T1 and T5 levels. In the GA + TEA group, the patients received a 20-mg bolus of 0.25% bupivacaine through epidural catheters 1 hour before surgery, and this was followed by the infusion (20 mg/h) of 0.25% bupivacaine. In all patients, ITA free blood flow was measured before cardiopulmonary bypass and without the administration of any vasodilatory agent. A short segment of ITA was excised for histologic examination; immunocytochemistry analysis was performed using antirabbit polyclonal VEGF antibody, rabbit polyclonal inducible nitric oxide synthase (i-NOS) antibody, and adenosine anti-A2B receptor antibody. The immunoreactivity rates then were evaluated. MAIN RESULTS: The mean ITA free flow in the GA + TEA group was significantly higher than in the GA group (56.0 ± 9.0 mL/min v 39.6 ± 14 mL/min, p = 0.001). Immunostaining intensity in the sections after incubation with each primary antibody increased in the GA + TEA group compared with the GA group. CONCLUSIONS: The results of this study indicated that TEA increased ITA free blood flow significantly via increased VEGF, i-NOS, and adenosine-A2B receptor expressions. Therefore, the use of TEA as an adjunct to GA might be considered as an alternative to vasoactive agents for increasing ITA flow in CABG surgery.

Chronic ethanol-induced glial fibrillary acidic protein (GFAP) immunoreactivity: an immunocytochemical observation in various regions of adult rat brain.

In the present study, the effects of chronic ethanol (ETOH) treatment on the glial fibrillary acidic protein (GFAP) immunoreactivity was investigated in adult rat brains. ETOH were administered as increasing concentrations of 2.4%-7.2% (v/v) gradually for 21 days. Immunocytochemistry revealed that chronic-ETOH treatment increased synthesis of GFAP. The increase in the diameter and the number of GFAP (+) cells were statistically significant compared with the control group (p <. 05). An increase of GFAP immunoreactivity was evident in various white matter and gray matter structures. We concluded that functional astrocytic cells responded to chronic ETOH exposure by increasing the synthesis of GFAP.

The effects of ethanol on insulin-like growth factor-I immunoreactive neurons in the central nervous system.

OBJECTIVE: To evaluate the effect of chronically ethanol treatment on insulin-like growth factor-I (IGF-I) synthesis in various adult brain regions using immunocytochemistry. METHODS: We performed this study at the Faculty of Medicine, Kocaeli University, Kocaeli, Turkey from March 2006 to October 2007. The vascular perfusion was utilized to fix the adult rat brains (10 for each group). After applying the routine histological techniques, the tissues were embedded in the paraffin. The immunohistochemical protocol was applied to the 10 um thick sections and the expression of IGF-I positive cells were observed in the neuro-anatomic areas. RESULTS: The distribution of IGF-I immunoreactive cells differed between the layers of the normal cerebral cortex and in the thalamic areas. In the alcoholic brain, the amount of IGF-I immunoreactive cells were decreased compared to the similar neuro-anatomical areas examined in the normal brains. CONCLUSION: The presence of IGF-I immunoreactivity in the neurons of the various neuro-anatomic areas demonstrates clearly that, these particular neurons are active in IGF-I synthesis. The decrease in the immunoreactivity of IGF-I in the chronically ethanol treated adult rat brain areas, show clearly that, ethanol effects negatively on the IGF-I synthesis.

Placental expression of insulin-like growth factor-I, fibroblast growth factor-basic, and neural cell adhesion molecule in preeclampsia.

OBJECTIVE: To investigate placental expression of insulin-like growth factor-I (IGF-I), fibroblast growth factor-basic (FGF-b), and neural cell adhesion molecule (N-CAM) in preeclampsia. STUDY DESIGN: An immunohistochemical analysis using IGF-I, FGF-b, and N-CAM antibodies was conducted on 4% paraformaldehyde-fixed placental tissues of preeclamptic patients (N = 14) and normotensive pregnant subjects (N = 10). Immunostaining patterns of chorionic villi and amniochorionic membranes were assessed. RESULTS: Significantly increased FGF-b and N-CAM immunoreactivities in cytotrophoblasts and increased FGF-b immunoreactivity in capillary endothelium of chorionic villi of preeclamptic subjects were noted. Significantly increased FGF-b and decreased N-CAM immunoreactivities in extravillous trophoblasts and decidual cells of amniochorionic membranes obtained from preeclamptic subjects were demonstrated. Additionally, a significantly increased IGF-I immunoreactivity was shown in decidual cells of preeclamptic cases. CONCLUSION: Investigation of the regional distribution of IGF-I, FGF-b, and N-CAM at the maternal-fetal interface establishes a better understanding of cell-specific altered growth processes, which may be associated with the pathogenesis of preeclampsia.

Immunocytochemistry of neuron specific enolase (NSE) in the rat brain after single and repeated epileptic seizures.

The aim of this study was to investigate neuron-specific enolase (NSE) immunoreactivity of the different brain regions after pentylenetetrazol (PTZ)- induced epileptic seizures in rats. Light microscopic examinations provided evidences for changes of neuronal activity after single and repeated seizures. The number of NSE (+) cells was well correlated with Nissl staining. The results suggest that NSE immunoreactivity may be a valuable marker for determination of the number of metabolically active neurons in different brain regions after single and repeated experimental seizures.

Effects of hyperbaric oxygen therapy on fibrovascular ingrowth in porous polyethylene blocks implanted under burn scar tissue: an experimental study.

Effects of hyperbaric oxygen (HBO) therapy on biointegration of porous polyethylene (PP) implanted beneath dorsal burn scar and normal skin were experimentally examined in Sprague-Dawley rats. In Group One (n=20), daily HBO treatments were given after the implantation of PP material under dorsal burn scar, whereas, in Group Two (n=20) no treatment was given following the same surgical procedure. In Group Three (n=20), PP was placed under dorsal normal skin and subsequently HBO therapy protocol was applied while Group Four (n=20) stayed without HBO treatment after the implantation. One, 2, 3 and 4 weeks after the implantations, sections were respectively taken from five rats from each group. Biointegration process and effects of HBO therapy were evaluated microscopically and the ratio of fibrovascular ingrowth (FVI) was determined for each rat. The results showed significantly superior FVI in Group One compared to Group Two and again FVI into PP under normal skin treated with HBO revealed better results against Group Four (p<0.05). Well-vascularized capsule formation and tissue integration was delayed both in Group Two and in Group Three in the first 3 weeks. In conclusion, HBO therapy enhances biointegration of PP in hypoxic burn scar areas via improving collagen synthesis and neovascularization; otherwise, it apparently delays tissue ingrowth into porous structure implanted in normal healthy tissues.

In vivo observation of leukocyte-endothelium interaction in ischemia reperfusion injury with the dorsal window chamber and the effects of pentoxifylline on reperfusion injury.

OBJECTIVE: Ischemia reperfusion injury can cause failure in microsurgical operations. Interaction between leukocytes and endothelium is recognized as an integral step in ischemia reperfusion injury. Pentoxifylline is a methylxanthine derivative that has pharmacological properties that can be beneficial in ischemia reperfusion injury. The aim of this study was to investigate the in vivo effect of pentoxifylline on leukocyte-endothelium interaction in ischemia reperfusion injury. METHODS: Intravital fluorescent microscopy was used to observe leukocyte-endothelium interaction in a "dorsal window chamber" model. Twenty-eight postcapillary veins were analyzed in group 1, and twenty-two in group 2. Group 1 received 25 mg/kg pentoxifylline 20 min before reperfusion. Group 2 received an equivalent volume of 0.9% saline at the same time. The period of ischemia was 4 h. RESULTS: Quantification of leukocyte 'sticking' and 'rolling' was done before ischemia and at 30, 60, and 120 min after reperfusion. Offline video analysis was used for evaluating the results. Statistical evaluation showed that pentoxifylline significantly attenuated leukocyte 'sticking' and 'rolling' in postcapillary venules. It was also effective in preventing 'no-reflow' when compared with the control group. CONCLUSION: These results indicate pentoxifylline diminishes leukocyte-endothelium interaction, and may have a therapeutic role in preventing ischemia reperfusion injury in microsurgical operations.

Efficacies of caspofungin and a combination of caspofungin and meropenem in the treatment of murine disseminated candidiasis.

Disseminated candidiasis is relatively common in immunocompromised patients. The treatment protocol of these patients usually includes broad-spectrum antibiotics and also emprical antifungals initiated due to unresponsiveness to antibiotics. In this study the efficacies of caspofungin and meropenem - separately and together - in mice with disseminated candidiasis were studied. Immunocompetent mice were infected intravenously with 2x10(6) CFU of Candida albicans. At 24 h postinfection, intraperitoneal therapy was initiated and was continued for 7 days. Therapy groups included those given caspofungin (0.5, 1.25, 5 mg/kg/day), meropenem (20 mg/kg/day), and a combination of the two drugs. The outcome of therapy was evaluated by kidney tissue burden studies and histologic examination. In vitro, drug susceptibilities were tested by checkerboard analysis. Kidney CFU counts showed that mice that had received both drugs had lower residual burdens. Caspofungin was effective at doses of 0.5, 1.25, 5 mg/kg compared to infected untreated controls. In vitro, MICs of caspofungin and meropenem were <0.075 micro g/ml and >64 micro g/ml, respectively. Synergism was observed with the combination. Histopathology showed that the degree of inflammation was 25% less and tubular necrosis was more restricted in combined therapy than monotherapy. The results indicate that concurrent caspofungin and meropenem therapy may be beneficial.

Effects of chronic ethanol treatment on glial fibrillary acidic protein expression in adult rat optic nerve: an immunocytochemical study.

Glial fibrillary acidic protein (GFAP) is used as a marker of astrocyte response to various central nervous system injuries. In the present study, the effects of chronic ethanol administration on GFAP immunoreactivity were evaluated in astrocytes of the adult optic nerve head. The results demonstrated that ethanol exposure significantly and dramatically increases GFAP immunoreactivity and the number of immunoreactive astrocytes (p<0.001). In addition, GFAP immunoreactive cells in the optic nerve showed extensive hypertrophy (p<0.001).

Protective effect of IGF-1 on experimental liver cirrhosis-induced common bile duct ligation.

BACKGROUND/AIMS: The causes of malnutrition in liver cirrhosis are multifactorial. Levels of IGF-1 (insulin like growth factor-1) that is a crucial regulator of intermediary metabolism decreases. The aim of this study was to analyze the effect of IGF-1 supplementation during liver cirrhosis induced by common bile duct ligation. METHODOLOGY: Rats were divided into five different groups: One sham and four experimental groups. Rats in three of four groups were treated with 2 micrograms/day IGF-1 with a different time of experiment in each group. Blood biochemical parameters, tissue malondialdehyde, glutathione levels and the activity of tissue antioxidant enzymes and conventional and immunohistochemical analysis of liver samples were studied for each group. RESULTS: Serum albumin, total protein, fibrinogen levels decreased and prothrombin time was prolonged in the bile duct ligated and transected experimental group but not in the IGF-I treated rats compared with the rats in sham group. Liver malondialdehyde levels significantly increased in control group but not in IGF-1 treated groups. The activities of antioxidant enzymes were decreased compared with the other groups. Histopathology findings of liver biopsy demonstrated intense degree fibrosis and overexpression of fibroblast growth factor and desmin in the control group but a lesser degree of those in the IGF-1 treated groups. CONCLUSIONS: IGF-1 treatment improves liver function and decreases oxidative liver damage and histopathological findings. Further studies are required to delineate the mechanisms of protective effects of IGF-1.

Localization of neural cell adhesion molecule and pan-cadherin immunoreactivity in intrauterine growth-retarded newborn rat kidneys.

To examine the expression and distribution pattern of neural cell adhesion molecule (N-CAM) and pan-cadherin immunoreactivity in intrauterine growth retardation (IUGR) newborn kidneys, we used a rat model of maternal protein restriction throughout pregnancy. Weak or moderate immunoreactivity for N-CAM and pan-cadherin was seen in some proximal tubules, in the thick segments of Henle, and in the collecting tubules of the control sections. However, the number of tubules expressing N-CAM and pan-cadherin was increased in the IUGR group compared with the control group. Increased density of N-CAM and pan-cadherin immunoreactivity was observed mostly in the proximal tubules, in the thick segments of Henle, and in the collecting tubules of IUGR newborn rat kidneys. Furthermore, N-CAM and pan-cadherin immunoreactivity was present in the thin limb of Henle in the IUGR group, whereas it was absent in the control group. Glomeruli were negative in both groups except for some glomeruli that showed very weak N-CAM staining in the IUGR group. Thus it was demonstrated for the first time that IUGR newborn rat kidneys express N-CAM and cadherin adhesion molecules at specific sites of the nephron.

Expression of cell adhesion molecules in the adriamycin-induced esophageal atresia rat model.

Cell adhesion molecules are well-known membrane glycoproteins widely expressed during embryonic development that play a crucial role in cell division, migration and differentiation. We investigated the cell-matrix relationship using N-CAM and pan-cadherin adhesion molecules in the adriamycin-induced esophageal atresia (EA) rat model in the hope of finding a clue to the mechanisms of this unique anomaly.Time-mated pregnant Sprague-Dawley rats were given either saline or adriamycin on days 8 and 9 of gestation. Embryos were harvested on the 18th day of gestation. Esophageal specimens obtained from adriamycin-exposed embryos with (EA+) or without esophageal atresia (EA-) and from saline-exposed embryos were immunostained with N-CAM and pan-cadherin primary antisera. The esophageal specimens from control and EA- groups revealed similar immunostaining properties: weak N-CAM and pan-cadherin immunoreactivity. In contrast, the EA+ group showed intense immunoreactivity. Our study demonstrated an increased synthesis of N-CAM and pan-cadherin in the epithelial cells of the atretic esophagus and trachea. These results suggest that embryonic cell-cell and cell-matrix interactions may play a crucial role in the development of adriamycin-induced EA.

Immunohistochemical analysis of neural cell adhesion molecule (N-CAM) and pan-cadherin in the small intestine of intrauterine growth-retarded newborn rats caused by maternal protein malnutrition.

Cell-cell and cell-matrix adhesion molecules play an important role in morphogenesis, cell signaling and are involved in cell proliferation, cell death, cell polarization and differentiation. In the present study, we investigated N-CAM and pan-cadherin expression in small intestine of intrauterine growth-retarded (IUGR) newborn rats after maternal protein malnutrition during pregnancy. N-CAM and pan-cadherin immunostaining was increased in small intestine of IUGR newborn rats. This increase was evident in epithelial cells on villi, lamina propria, submucosa, muscularis mucosa and muscularis externa. The increase in numbers of villous N-CAM-positive and pan-cadherin-positive epithelial cells was statistically significant (p < 0.001). In most areas, crypts did not show any immunopositive epithelial cells or showed decreased expression of the adhesion molecules. Although the villous height was decreased in IUGR rats, the decrease was statistically not significant. Expression and recruitment of N-CAM and pan-cadherin in small intestine of newborn IUGR rats may indicate a direct or indirect involvement of adhesion mechanisms or signaling in the growth retardation process.