Special Isue: Virtual anatomy, histology and embryology in research and education. (Special Isue: Virtual anatomy, histology and embryology in research and education.)

This issue contains 13 articles on the use of virtual anatomy, histology and embryology in research and education;digital histological morphometry of the human pineal gland in a postmortem study, with endocrine and neurological clinical implications;an international collaborative approach to learning histology using a virtual microscope;delivery anatomy kits to help keep practical veterinary classes during the COVID-19 pandemic;how virtual animal anatomy facilitated a successful transition to online instruction and supported student learning during the coronavirus pandemic;using videos in active learning in veterinary anatomy;dissection videos as a virtual veterinary anatomy peer learning tool at the University of Tehran during the COVID-19 pandemic;a new virtual platform for teaching comparative animal neuroanatomy based on metameric slices of the central nervous system;application of student remote and distance research in neuroanatomy by mapping Dscaml1 expression with a LacZ gene trap in mouse brain;implementing a multi-colour genetic marker analysis technique for embryology education;impact of COVID-19 on student attainment and pedagogical needs when undertaking independent scientific research;extended reality veterinary medicine case studies for diagnostic veterinary imaging instruction and assessing student perceptions and examination performance and students' performance in teaching neuroanatomy using traditional and technology-based methods. 16 proceedings from the Trans-European Pedagogic Anatomy Research Group (TEPARG) Hybrid Meeting entitled "Hybrid Anatomy Education: Barriers and Enablers for Students and Educators" held in Barcelona, Spain, during 5 March 2022, are also included.

PEG placements during the COVID-19 pandemic An audit of the procedures performed by a single consultant operator at a tertiary teaching hospital

PEG feeding provides a valuable nutritional access for patients with a functional gastrointestinal tract. The aim of this project was to audit all the PEG procedures performed by a single consultant operator during the Covid-19 pandemic including the indications, outcomes and complications. All the procedure reports were accessed to identify the patients, indications and immediate outcomes. For every patient, all the letters from all specialties were accessed for the dates following the procedure through the clinical records platforms to identify any later complications. A total of 92 procedures were performed between 15/3/2020 and 31/4/2021 in a total of 84 patients. Lists were operating at less than half capacity compared to pre Covid-19. 65 were planned PEG insertions, 17 were planned removals, and 10 were planned replacements. 5 of the procedures were for PEG-J insertion or replacement. The main indication was Head and Neck Ca in 59/92 procedures followed by CVA 9/92, chronic nausea/vomiting/gastroparesis in 6/92, dysphagia with or without aspiration risk in 4/92, MND in 4/92, CNS tumour post-op (pineal gland) in 2/92, cerebral palsy in 1/92, multiple sclerosis in 1/92, neurodegenerative disorder in 1/92, neuromuscular disorder in 1/92, chronic pancreatitis in 1/92, cystic fibrosis in 1/92, depression with poor oral intake in 1/92 and learning difficulties in 1/92. 83/92 procedures were completed successfully. 2 procedures had a failed intubation, 1 because of a subglottal stricture. The rest of the abandoned procedures were due to patient distress (2/92), high oesophageal stricture (1/92), failed cannulation (1/92), body habitus (1/92), stomach not translluminated and patient desaturation (1/92). One of the planned replacements failed because of a buried bumper. In two patients there was a small leak around the PEG site, 1 identified in the endoscopy room, 1 a few weeks later but both were managed conservatively and the PEG was kept in place. No other complications identified. From October 2020 the consistent use of Corflo PEGs reduced the service demands as these can be easily removed in the community. Lists during the COVID-19 pandemic were significantly impacted, especially UGI procedures, as these are aerosol generating procedures. The vast majority of the procedures are completed successfully and there are no significant complications. Most failed procedures are due to patient related factors such as tolerance and anatomical factors. The use of PEGs that can be removed in the community avoiding further endoscopic procedures is a valuable tool especially in this pandemic and early post-pandemic setting.

The regulation of melatonin on female reproduction

Since melatonin was discovered by humans in 1958. It is believed to be related to vertebrate reproduction, especially seasonal reproduction. It is in a large measure attributed to the fact that melatonin is secreted by the pineal gland and exhibits a unique circadian rhythm. The diurnal variation of melatonin levels in the blood of vertebrates is accessed not just for reproductive rhythms, but for seasonal cycles of metabolic activities, immune functions, and behavioral expression. With the widespread application of modern technology, the effect of seasons on reproductive performance has been weakened, but it is because of the rhythmic secret ion characteristics of melatonin that animal reproduction and even human reproduction have greater controllability. In the past 60 years, a large number of studies reveal the effect of melatonin on animal reproduction. Nowadays, faced with the impact of African swine fever and novel coronavirus outbreaks on animal husbandry in China, how to improve female animal reproduction economically and effectively is the key to animal husbandry reproduction. This article mainly discusses about the researches of melatonin on female reproduction in terms of follicular development, hormone levels of organism, and embryonic development. The purpose of this article is to provide an effective basis for new research in this field, especially those with relevance to animal re- production and reproductive medicine, and for animal reproduction and production.