BackgroundCoronavirus disease-2019 (COVID-19) has caused a great global threat to public health. The World Health Organization (WHO) has declared COVID-19 disease as a pandemic, affecting the human respiratory and other body systems, which urgently demands for better understanding of COVID-19 histopathogenesis.ObjectiveData on pathological changes in different organs are still scarce, thus we aim to review and summarise the latest histopathological changes in different organs observed after autopsy of COVID-19 cases.Materials and methodsOver the period of 3 months, authors performed vast review of the articles. The search engines included were PubMed, Medline (EBSCO & Ovid), Google Scholar, Science Direct, Scopus and Bio-Medical. Search terms used were ‘Histopathology in COVID-19’, ‘COVID-19’, ‘Pathological changes in different organs in COVID-19’ or ‘SARS-CoV-2’. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2009 guidelines were used for review writing.ResultWe identified various articles related to the histopathology of various organs in COVID-19 positive patients. Overall, 45 articles were identified as full articles to be included in our study. Histopathological findings observed are summarised according to the systems involved.ConclusionAlthough COVID-19 mainly affects respiratory and immune systems, but other systems like cardiovascular, urinary, gastrointestinal tract, reproductive system, nervous system and integumentary system are not spared, especially in elderly cases and those with comorbidity. This review would help clinicians and researchers to understand the tissue pathology, which can help in better planning of the management and avoiding future risks.

The paucity of knowledge about severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2)‐specific virulence factors has greatly hampered the therapeutic management of patients with coronavirus disease 2019 (COVID‐19). Recently, a cluster of studies appeared, which presented empirical evidence for SARS‐CoV‐2‐specific virulence factors that can explain key elements of COVID‐19 pathology. These studies unravel multiple structural and nonstructural specifics of SARS‐CoV‐2, such as a unique FURIN cleavage site, papain‐like protease (SCoV2‐PLpro), ORF3b and nonstructural proteins, and dynamic conformational changes in the structure of spike protein during host cell fusion, which give it an edge in infectivity and virulence over previous coronaviruses causing pandemics. Investigators provided robust evidence that SARS‐CoV‐2‐specific virulence factors may have an impact on viral infectivity and transmissibility and disease severity as well as the development of immunity against the infection, including response to the vaccines. In this article, we are presenting a summarized account of the newly reported studies.

The core values in medical practice which are essential for the humane outlook of a physician are clubbed within the domain of medical professionalism. Professionalism along with other discipline‐independent skills (human skills) is propagated implicitly in medical schools as components of a “hidden curriculum.” Evidence suggests a strong association between “hidden curriculum” delivery and development of professionalism in the human dissection room. In this review article, the authors have tried to highlight a few exclusive practices adopted by medical schools which enhance the implementation of the “hidden curriculum” within the practice of human dissection and successfully inculcate the key components of professionalism such as integrity, respect, and compassion among students. These distinctive concepts are aimed at humanizing the experience of anatomical dissection by revealing the identity of the donors along with their personal details either through display of video clips of donor interviews, interactions with the family members of the donor over a meal or recognition of the donor as a mentor and organizing memorial services in honor of donors after conclusion of the dissection in the presence of their family members. The resounding success of these good practices in building professionalism among medical students from the onset of the academic curriculum has signaled a new chapter in anatomical sciences education. It has become imperative to recognize the visionary efforts of a select few medical educators and begin incorporating these recent trends into the delivery of the “hidden curriculum” within the evolving gross anatomy education model.

Several studies have described unusually high incidence of vascular thrombosis in coronavirus disease-2019 (COVID-19) patients. Pathogenesis of the vascular thrombosis in COVID-19 is least understood for now and presents a challenge to the treating physicians. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the causative pathogen for COVID-19, has been shown to bind to angiotensin converting enzyme 2 (ACE2) protein in human epithelial cells which facilitates its entry in the organ and mediate tissue specific pathogenesis. For ACE2 mediated cell entry of the SARS-CoV-2, co-expression of one more protein—Transmembrane protease serine 2 (TMPRSS2) is essential. Existing studies suggested significant expression of ACE2 and TMPRSS2 in human vascular endothelium. Vascular endothelial dysfunction can potentially activate coagulation cascade eventually resulting in thrombosis. ACE2 has proven role in the maintenance of endothelial integrity inside the vessels. Existing in situ evidence for SARS-CoV-1 (the causative agent for SARS pandemic of 2002, which shared ACE2 as cell entry receptor) suggested that virus binding can downregulate ACE2, thus can induce endothelial dysfunction. Recently, in situ evidence has been presented that SARS-CoV-2 can infect cells in engineered human vascular endothelium, which can be effectively blocked by using clinical-grade recombinant human ACE2. Based on the circumstantial evidence present in the literature, we propose a SARS-CoV-2 cell entry receptor ACE2 based mechanism for vascular thrombosis in COVID-19 patients.

Manifestation of neurological symptoms in certain patients of the ongoing pandemic of coronavirus disease-2019 (COVID-19) presents a challenge for neuroscientists to explain underlying pathophysiology. COVID-19 is caused by a new strain of coronavirus severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). SARS-CoV-2 belongs to the genus of betacoronaviruses which also includes SARS-CoV-1 and MERS-CoV; causative agents for severe acute respiratory syndrome (SARS) in 2002 and Middle East respiratory syndrome (MERS) in 2012, respectively. It is known that SARS-CoV-2, through its receptor-binding domain (RBD) present at its spike (S) protein, binds to a human cell surface receptor called angiotensinconverting enzyme 2 (ACE2) (Hoffmann et al., 2020). Following

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More than one and a half years have elapsed since the commencement of the coronavirus disease 2019 (COVID-19) pandemic, and the world is struggling to contain it. Being caused by a previously unknown virus, in the initial period, there had been an extreme paucity of knowledge about the disease mechanisms, which hampered preventive and therapeutic measures against COVID-19. In an endeavor to understand the pathogenic mechanisms, extensive experimental studies have been conducted across the globe involving cell culture-based experiments, human tissue organoids, and animal models, targeted to various aspects of the disease, viz., viral properties, tissue tropism and organ-specific pathogenesis, involvement of physiological systems, and the human immune response against the infection. The vastly accumulated scientific knowledge on all aspects of COVID-19 has currently changed the scenario from great despair to hope. Even though spectacular progress has been made in all of these aspects, multiple knowledge gaps are remaining that need to be addressed in future studies. Moreover, multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have emerged across the globe since the onset of the first COVID-19 wave, with seemingly greater transmissibility/virulence and immune escape capabilities than the wild-type strain. In this review, we narrate the progress made since the commencement of the pandemic regarding the knowledge on COVID-19 mechanisms in the human body, including virus–host interactions, pulmonary and other systemic manifestations, immunological dysregulations, complications, host-specific vulnerability, and long-term health consequences in the survivors. Additionally, we provide a brief review of the current evidence explaining molecular mechanisms imparting greater transmissibility and virulence and immune escape capabilities to the emerging SARS-CoV-2 variants.

The SARS-CoV-2 is a recently identified positive sense single stranded RNA virus and member of the coronavirus family of viruses. It is thought to be the etiological factor for the ongoing COVID-19 pandemic. This virus is thought to have originated from bats and acquired ability of human-to-human transmission. While SARS-CoV-2 is relatively benign, it has infected more than half a million people (as of March 29 th 2020) worldwide and the number of infected people continues to rise. More than 170 countries have reported COVID-19 positive cases. With a mortality rate of less than both the previous coronavirus outbreaks, COVID-19 has (conversely) caused the death of over 33,980 (as of 29 th March, 2020 at 22.00 hours EDT) people worldwide and the number is increasing. Given the enormous impact of this virus on human health and wellbeing and consequent devastating impacts on world trade, economics and quality of life, it is important to understand this virus better and get insight into its pathogenic mechanisms which will aid in devising effective measure to curb its spread and predict future pattern of its interaction with humans. Though very little is known about this SARS-CoV-2 but its mechanisms and patterns of spread can be speculated (with caution, nevertheless) from what we know about its closest relatives SARS-CoV-1 (responsible for SARS-2002 epidemic) and MERS-CoV (responsible for MERS-2012 epidemic). In the present review, we aim at bringing together the coherent and peer reviewed literature about the SARS-CoV-2 and its close relatives and try to understand its infection patterns and reconstruct its pathogenic mechanisms with anecdotes on diagnosis and future directions. We hope that this paper will serve the purpose of being a reliable source of information to scientists, clinicians and general public. 2020) named Huanan which was subsequently closed on January 1 st , 2020. It was later reported that individual greater than 60 years of age and those with other comorbid conditions are susceptible to severe disease and may even die (Cascella et al., 2020). The emergence of