Histomorphometry of the cortical layers and the dentate nucleus of the human fetal cerebellum.

Objectives: This study was aimed at determining the histomorphometry of the cerebellar cortical laminae and the dentate nucleus of the human fetal cerebellum; the number and shape of the neurons; and the gestational age of appearance of the cerebellar folia, white matter and arbor vitae cerebelli. Methods: Microscopic sections of the human fetal cerebellum stained with hematoxylin and eosin and Bielschowsky silver stain were studied. Results: The thickness of the cortical laminae of the human fetal cerebellum varied among gestational weeks as follows: external granular layer: 36.06 ± 9.36-50.05 ± 34.06 µm, molecular layer: 32.76 ± 17.16-52 ± 28.6 µm, Purkinje cell layer: 9.36 ± 6.8-15.6 ± 4.68 µm and internal granular layer: 66.65 ± 24.42-146.63 ± 47.79 µm. Similarly, the number of neurons per field of view at 1000X under a compound microscope varied among gestational weeks as follows: external granular layer: 89.92 ± 42-142.84 ± 50, molecular layer: 15 ± 12.5-25 ± 8.25, Purkinje cell layer: 3.5 ± 1-5 ± 2.5 and internal granular layer: 98.5 ± 69.75-224 ± 47.White matter in the fetal cerebellum was already present at the age of 12th gestational week, whereas cerebellar folia appeared at 16-20 gestational weeks. Arbor vitae cerebelli and the dentate nucleus became conspicuous after the 20th gestational week. Fetal neurons were round except for Purkinje cells. Conclusions: The thickness and neuronal counts of the human fetal cerebellar cortical layers and the measurements of the dentate nucleus along with other histomorphological features varied with gestational age from the 12th week of gestation until birth.

Comparative role of SOX10 gene in the gliogenesis of central, peripheral, and enteric nervous systems.

SOX10 gene and SOX10 protein are responsible for the gliogenesis of neuroglia from the neural crest cells. Expression of SOX10 gene encodes SOX10 protein which binds with DNA at its minor groove via its HMG domain upon activation. SOX10 protein undergoes bending and changes its conformation after binding with DNA. Via its transactivation domain and HMG domain, it further activates several other transcription factors, these cause gliogenesis of the neural crest cells into neuroglia. In literature, it is stated that the SOX10 gene helps in the formation of schwann cells, oligodendrocytes, and enteric ganglia from neural crest cells. Altered expression of the SOX10 gene results in agliogenesis, dysmyelination, and demyelination in the nervous system as well as intestinal aganglionosis. This review highlighted that there is a role of the SOX10 gene and SOX10 protein in enteric gliogenesis from the neural crest cells.

Histomorphology of enteric neurons and enteric ganglia in different layers of human fetal colon.

Objective: Literature shows very few studies explaining morphology of enteric neurons and ganglia in humans. This study was aimed at determining the morpho-histology of enteric neurons and ganglia in human fetal colon. Methods: Histological sections of human fetal colon were stained with hematoxylin and eosin, Bielschowsky's silver and Masson's trichrome stains to study the morpho-histology of enteric neurons and ganglia. Results: Enteric neurons scattered in the early weeks of development and ganglionated as the fetal age progresses. Migration of enteric neurons was less and in scattered form during early weeks and as the age progresses it was more and in ganglionated form. Enteric neurons were round, oval, pyramidal and flat in all layers of colon. Enteric ganglia in serosa were oval in early weeks, oval and elongated in late weeks whereas in between the muscle layers and submucosa they were few and oval, irregular and elongated. Distance between the enteric ganglia increased in serosa but fluctuated in the remaining layers as the gestational age progressed. Number of enteric neurons and ganglia was more in serosa and less in other layers during early weeks and as the fetal age progressed they decreased in serosa but increased in other layers. Conclusion: There are various shapes and numbers of enteric neurons and ganglia and distances between the ganglia in different layers of fetal colon.

Unmapped landmarks around branches of the Superior Laryngeal Nerve: An exploratory cadaveric study.

OBJECTIVES: Preserving the External Branch of Superior Laryngeal Nerve (EBSLN) and Internal Branch of Superior Laryngeal Nerve (IBSLN) is essential during thyroidectomy. However, due to potential distortions caused by large goitres, the present anatomical landmarks used to identify these nerves are flawed. Although under such circumstances, bony landmarks may offer more stable reference points, not much has been explored in this regard. This study measures the distance between the most vulnerable points of the EBSLN and IBSLN and their relatively unexplored bony landmarks, such as the hyoid bone and thyroid notch as well as soft-tissue landmarks like the origin of the Superior Thyroid Artery (STA) and carotid bifurcation. METHODS: An exploratory cadaveric study was conducted in a medical school affiliated with a tertiary care hospital. The detailed analysis included 13 sides from 8 cadavers. RESULTS: The average distance from the EBSLN piercing site to the greater cornua of the hyoid bone, thyroid cartilage prominence, origin of the STA, and carotid bifurcation was 35.1(±7.2) mm, 33.3(±3.8) mm, 25.7(±6.3) mm, and 31.5(±5.0) mm, respectively and from the IBSLN piercing site was 15.9(±5.9) mm, 32.9(±4.7) mm, 16.3(±4.2) mm, and 20.7(±5.9) mm, respectively. For most cadavers, the distal EBSLN had Cernea type 2a-like relationship with the STA. Certain variations were also observed in the way these nerves branched with respect to the origin of the STA. CONCLUSIONS: This study provides metric information (linear measurements) regarding the distance between the branches of SLN and certain unique landmarks. This could potentially aid in minimising intraoperative trauma to these branches.

One-month long foundation course for newly joined Indian medical undergraduates: Faculty and students' perspective.

BACKGROUND: A one-month long foundation course has been introduced at the entry-level for first-year MBBS (Bachelor of Medicine and Bachelor of Surgery) students in the medical institutions across India from 2019. Therefore, the present study is aimed at describing the experience of implementing a one-month long foundation course conducted for the Competency-based Undergraduate Medical Curriculum (CBUC) of Indian Medical Graduate as per the guidelines from the National Medical Commission (NMC) (erstwhile Medical Council of India, MCI). We have evaluated the student and faculty perceptions towards the effectiveness of the program. METHODS: The foundation course had six modules Orientation, Skills, Field visit to Community Health Centre, Professional Development including Ethics, Sports and Extracurricular activities, Computer Skills, and Language enhancement program. Regular feedback wascollected from students (N = 250) and teachers (N = 26) involved in the Foundation course using a semi-structured questionnaire. The program's overall feedback was also obtained at the end of the course, using a validated questionnaire. The quantitative findings were expressed in frequency and percentage. The qualitative observations (reflections of students and faculty) were subjected to thematic. RESULTS: The students and faculty appreciated the one-month long foundation course. The course's defined objectives were met as indicated by most students (98.4%) and faculty (75%). The course seemed to be useful for students to embark on a formal MBBS curriculum. It also exposed them to new knowledge and practices, as indicated by the feedback. Thematic analysis of the students' and faculty's reflections was carried out and two themes were identified, i.e., 'strengths' and 'challenges.' The Foundation Course Committee will work out appropriate remedial measures to overcome the challenges in the future sessions for subsequent batches. CONCLUSIONS: The one-month-long foundation course was found to be beneficial for newly joined students to get introduced and adjusted to higher education systems' demands. Also, the challenges faced during the program needs to be addressed with suitable remedial measures while implementing for subsequent batches. This effort will ensure a smooth conduct of the foundation course for the future batches of medical undergraduates and make the program more effective.

Cadaver as a first teacher: A module to learn the ethics and values of cadaveric dissection.

OBJECTIVES: The undergraduate medical students must be made aware of the ethical and humanistic values of cadaveric dissection. This study therefore designed, implemented, and evaluated the impact of the module 'Cadaver as a Teacher' (CrAFT) that examines the ethical values of cadaveric dissection. METHODS: This prospective, multimethod study involved 447 first-year undergraduate medical students who had participated in all three sessions of the CrAFT module. Activities included interactive lectures, individual assignments, and a poster-making competition. Students offered a silent tribute and wrote words of gratitude down on a tribute wall. They also expressed their thoughts in the form of essays, poems, and collages. These reflections were qualitatively analysed to generate themes. At the end of the module, an online quiz was conducted to assess the knowledge gained by the students. Their scores were correspondingly recorded and calculated. RESULTS: The major themes identified were: cadaver as a teacher, acknowledgement and thanksgiving, bonding, and empathy. Out of all the test takers, 316 students (94.32%) scored more than a five out of ten. The students strongly felt that the module effectively sensitised them towards the ethical and humanitarian aspects of handling cadavers. CONCLUSIONS: The implementation of an educational module about cadavers is a novel approach towards sensitising medical students. The students believed that sensitising them early on would have helped them establish a practice grounded in professionalism, human values, and empathy.

Effect of Vitamin D Analogue on Rosuvastatin-Induced Myopathy in Wistar Rats.

OBJECTIVES: Statin-induced myopathy is one of the major causes of poor adherence and discontinuation of this medication. There are contrary results regarding association of vitamin D insufficiency with statin-induced myopathy. This study was done to determine the effect of the vitamin D3 analogue alfacalcidol on Rosuvastatin-induced myopathy in rats. Methodology. Animals were divided into six groups with 6 rats in each group. Groups I and II acted as controls, Group III and Group IV were administered Rosuvastatin 120 mg/kg/day and 160 mg/kg/day, Groups V and VI were administered alfacalcidol 0.1 µg/kg/day in addition to Rosuvastatin 120 mg/kg/day and 160 mg/kg/day, respectively. All drugs were administered orally for 15 days. Plasma creatine kinase (CK) levels were estimated on day 10 and day 15. Animals were sacrificed and muscles were sent for histopathological examination. RESULTS: On day 10, Groups V and VI showed a statistically significant increase in plasma CK levels as compared to the control (p < 0.001) and were significantly lower (p < 0.001) as compared to Groups III and IV, respectively. However, on day 15, plasma CK levels in Groups V and VI were comparable to those of control groups with a nonsignificant difference (p > 0.05). On comparing the histology, Groups V and VI showed a significant difference as compared to statin-only groups (Groups III and IV) as there were signs of regeneration, less splitting, and fragmentation of muscle fibres. CONCLUSION: The present study shows that the vitamin D analogue alfacalcidol prevents statin-induced myopathy. The serum CK levels are comparable to the control group on day 15 of vitamin D administration.

Histogenesis and Histomorphometric study of Human Fetal Small Intestine.

BACKGROUND: Intestine plays a major role for the normal growth of the fetus during the prenatal period. The process of the embryonic development is not quantified histologically. Therefore the main aim of the study was to measure the thickness of all part of the wall of the small intestine that are mucosa, submucosa and muscularis externa and to look for the appearance of the Brunner's glands and Peyer's patches in the submucosa of duodenum and ileum. METHODS: The present study was carried out on 30 fetuses of gestational ages ranging from 11-36 weeks. Ten fetuses from each trimester were used in the study. Fetal small intestine were dissected carefully, and were separated as duodenum, jejunum & ileum and fixed in formalin solution. The tissue was processed for histology and then slides were stained with Haematoxylin and Eosin. The microscopic features were noted using light microscope. RESULTS: The thickness of the mucosa, submucosa and the muscularis externa was observed to be increased in first trimester, decreased in the second trimester and again increased in the third trimester, which could be because of the increase cell turnover and the arrangement of the collagen fibers as to support the mucosa and the muscularis externa. CONCLUSION: Thus, the knowledge of the histogenesis and histomorphometry of the human fetal small intestine is crucial for the adult gastroenterologist to appreciate, because of the potential for these early life events to affect the responsiveness of the intestine to physiological or pathological challenges in later life.

Study of cephalic index in Indian students / Estudio del índice cefálico en estudiantes Indios

Cephalic index is important parameter for deciding race and sex of an individual whose identity is unknown. Cephalic index and head shape are greatly affected by geographical, sex, age and racial factors. Present study aimed at working out cephalic index in Indian students. 100 students were taken as subjects and head length, head breadth were measured. Indian males had mean cephalic index of 77.92 and they were mesocephalic and females had mean cephalic index of 80.85 and they were brachycephalic. The comparison was statistically significant. The data is utmost important in forensic medicine, anthropology and in genetics.

El índice cefálico es un parámetro importante para determinar la raza y el sexo de un individuo cuya identidad es desconocida. El índice cefálico y la forma de la cabeza se ven afectados en gran medida por la geografía, el sexo, la edad y factores raciales. El presente estudio tuvo como objetivo la elaboración de índice cefálico de estudiantes indios. Cien estudiantes fueron tomados como sujetos de estudio, y fue medida la longitud y amplitud de la cabeza. Los hombres indios tuvieron una media del índice cefálico de 77,92 correspondiente a individuos mesocéfalos, mientras que las mujeres tuvieron una media del índice cefálico de 80,85 siendo braquicéfalas. La comparación fue estadísticamente significativa. Los datos obtenidos son de importancia para la medicina forense, la antropología y la genética.

Estimation of stature from the length of the sternum in South Indian females.

Estimation of stature is one of the principal elements in practical forensic casework involving examination of skeletal remains. The present study was undertaken to estimate stature from the length of the sternum in South Indian females using a linear regression equation. The material for the present study consisted of intact sternums belonging to adult females of South Indian origin aged between 25 and 35 years of age obtained during medico-legal autopsies. The length of the sternum was measured as the combined length of the manubrium and the mesosternum (body of the sternum) from the incisura jugularis (central suprasternal notch) to the mesoxiphoid junction along the mid-sagittal plane using vernier calipers. A linear regression equation [Stature = 111.599 + (3.316 × Length of the sternum)] was derived to estimate stature from the length of the sternum. The correlation coefficient was 0.639. The standard error of the estimate was 4.11 cm. The present study concludes that the length of the sternum is a reliable predictor of stature in adult South Indian females and can be used as a tool for stature estimation when better predictors of stature like the long bones of the limbs are not available when examining skeletal remains.

Stature estimation from the length of the sternum in South Indian males: a preliminary study.

Estimation of stature is one of the important initial steps during forensic analysis of human skeletal remains. The aim of the present study was to derive a linear regression formula for estimating stature of adult South Indian males from the length of the sternum. The study included 35 male sternums of South Indian origin dissected from cadavers during medico-legal autopsies. The linear regression equation [Stature=117.784 + (3.429 x Sternal length)] was derived to estimate the stature from the length of the sternum. The correlation coefficient was 0.638. The standard error of the estimate was 5.64 cm. This preliminary study concludes that the length of the sternum can be used as a tool for stature estimation in adult South Indian males.