RESUMEN
We describe the case of a 12-year-old boy who presented via teledermatology with a 5-6-year history of multiple lesions on the right side of his face. They were unchanged since their initial appearance at 6 years of age but were slowly increasing in number across his right cheek and extending onto the chin. Although the lesions were asymptomatic, growing older had made him feel increasingly self-conscious. He was otherwise fit and well, and attended mainstream school, with no past medical history or family history of note. Perinatal and birth history were also uneventful. On examination, he had multiple, 1-2-mm, erythematous papules confined to the right cheek and right chin. Dermoscopy showed an unusual pattern of vessels with nonspecific globules in between. The rest of the skin, hair and nails were entirely normal in appearance. There were no systemic symptoms and a detailed general and systemic examination, as well as radiological imaging, did not reveal any abnormality. An excisional biopsy was taken of one of the lesions, with histological examination demonstrating focal superficial telangiectasia with associated bland round-tospindle cell proliferation, appearances most in keeping with an angiofibroma. This correlated well clinically, apart from unilateral facial angiofibromas being the solitary finding in our patient. Facial angiofibromas - also called adenoma sebaceum - are well described as part of the cutaneous manifestations of tuberous sclerosis (TSC). Classically, these appear as a facial rash in the form of small pink or red spots across the cheeks and nose in a butterfly distribution, at between 3 and 10 years of age, increasing in size and number until adolescence. TSC is an autosomal dominant disorder with defective mammalian target of rapamycin (mTOR) signalling, characterized by hamartomas in many organs, particularly the skin, central nervous system, renal and cardiovascular systems. The clinical presentation is variable, with other well known and frequently reported cutaneous findings such as shagreen patches, ash-leaf macules and periungual fibromas. Unilateral multiple facial angiofibromas in the absence of other cutaneous or systemic manifestations of TSC - as in our patient - are rare, with only 13 reported cases. These may form part of the clinical spectrum of TSC as a probable consequence of cutaneous mosaicism in which a postzygotic genetic mutation has occurred. Our patient was referred for genetic testing, but this has been delayed as a result of the COVID-19 pandemic. Topical sirolimus 1% - an mTOR inhibitor - has been used with good effect for facial angiofibromas, and our patient also responded well to this.
RESUMEN
Viral infections cause damage to various organ systems by inducing organ-specific symptoms or systemic multi-organ damage. Depending on the infection route and virus type, infectious diseases are classified as respiratory, nervous, immune, digestive, or skin infections. Since these infectious diseases can widely spread in the community and their catastrophic effects are severe, identification of their causative agent and mechanisms underlying their pathogenesis is an urgent necessity. Although infection-associated mechanisms have been studied in two-dimensional (2D) cell culture models and animal models, they have shown limitations in organ-specific or human-associated pathogenesis, and the development of a human-organ-mimetic system is required. Recently, three-dimensional (3D) engineered tissue models, which can present human organ-like physiology in terms of the 3D structure, utilization of human-originated cells, recapitulation of physiological stimuli, and tight cell-cell interactions, were developed. Furthermore, recent studies have shown that these models can recapitulate infection-associated pathologies. In this review, we summarized the recent advances in 3D engineered tissue models that mimic organ-specific viral infections. First, we briefly described the limitations of the current 2D and animal models in recapitulating human-specific viral infection pathology. Next, we provided an overview of recently reported viral infection models, focusing particularly on organ-specific infection pathologies. Finally, a future perspective that must be pursued to reconstitute more human-specific infectious diseases is presented. Copyright © 2022 The Authors
RESUMEN
Background: According to preliminary sequences from 2010, 99.7% of the nucleotide sequences of the modern human and Neanderthal genomes are identical, compared to humans sharing around 98.8% of sequences with the chimpanzee. In contrast, the difference between chimpanzees and modern humans is approximately 1,462 mtDNA base pairs. Materials and Methods: Neanderthal-inherited genetic material is found in all non-African populations and was initially reported to comprise 1 to 4% of the genome. This fraction was later refined to 1.5 to 2.1%. We had gone through many researches of Neanderthals affected gene flow in humans. Results: It is estimated that 20% of Neanderthal DNA currently survives in modern humans. Modern human genes involved in making keratin, a protein constituent of skin, hair, and nails, have especially high levels of introgression. For example, approximately 66% of East Asians contain a POUF23L variant introgressed from Neanderthals, while 70% of Europeans possess an introgressed allele of BNC2. Our finding shines a light on an enzyme called dipeptidyl peptidase4 (DPP4). Scientists already know the protein allows another coronavirus, which causes Middle Eastern respiratory syndrome (MERS), to bind to and enter human cells. The new analysis, of DPP4 gene variants among COVID-19 patients, suggests the enzyme also provides SARS-CoV-2 with a second door into our cells, along with its usual infection route via the angiotensin-converting enzyme 2 (ACE2) receptor on cell surfaces. Conclusion: Most Europeans, Asians, and Native Americans harbor a handful of genes from Neanderthals, up 1.8% to 2.6% of their DNA. Studies of ancient DNA in Neanderthal fossils have shown the hominin's DPP4 gene subtly differs from the typical human one. Conclusion: The hominin's DPP4 gene inherited from Neanderthals plays a major role in Immune System Disorders and Lower Immune response in many diseases. This gene plays a major role in affecting humans with COVID-19 and spreading it through the world. All humans contain this gene from 1 to 4%. East Asians, Europeans, Middle and south Americans conveys more, hence, native Africans contain less amounts of hominin's DPP4 gene. Therefore, East Asians, Europeans, Middle and south Americans are prone to severe COVID-19.