Organelle genome fragmentation has been found in a wide range of eukaryotic lineages; however, its use in phylogenetic reconstruction has not been demonstrated. We explored the use of mitochondrial (mt) genome fragmentation in resolving the controversial suborder-level phylogeny of parasitic lice (order Phthiraptera). There are ∼5,000 species of parasitic lice in four suborders (Amblycera, Ischnocera, Rhynchophthirina and Anoplura), which infest mammals and birds. The phylogenetic relationships among these suborders are unresolved despite decades of studies. We sequenced the mt genomes of eight species of parasitic lice and compared them with 17 other species of parasitic lice sequenced previously. We found that the typical single-chromosome mt genome is retained in the lice of birds but fragmented into many minichromosomes in the lice of eutherian mammals. The shared derived feature of mt genome fragmentation unites the eutherian mammal lice of Ischnocera (family Trichodectidae) with Anoplura and Rhynchophthirina to the exclusion of the bird lice of Ischnocera (family Philopteridae). The novel clade, namely Mitodivisia, is also supported by phylogenetic analysis of mt genome and cox1 gene sequences. Our results demonstrate, for the first time, that organelle genome fragmentation is informative for resolving controversial high-level phylogenies.

The coronavirus (COVID-19) has greatly impacted healthcare systems worldwide, leading to an unprecedented rise in demand for healthcare resources. In anticipation of an acute strain on established medical facilities in Dallas, Texas, federal officials worked in conjunction with local medical personnel to convert a convention center into a Federal Medical Station capable of caring for patients affected by COVID-19. A 200,000 square foot event space was designated as a direct patient care area, with surrounding spaces repurposed to house ancillary services. Given the highly transmissible nature of the novel coronavirus, the donning and doffing of personal protective equipment (PPE) was of particular importance for personnel staffing the facility. Furthermore, nationwide shortages in the availability of PPE necessitated the reuse of certain protective materials. This article seeks to delineate the procedures implemented regarding PPE in the setting of a COVID-19 disaster response shelter, including workspace flow, donning and doffing procedures, PPE conservation, and exposure event protocols.

The COVID-19 outbreak is an unprecedented global public health challenge. It has a myriad of clinical presentations including fever, cough, vomiting, and diarrhea. Here, we present a unique case of COVID-19, with an atypical presentation of arthralgias and false-positive results for the chikungunya virus. By highlighting the importance of this rare association, we want physicians to be vigilant in the time of this pandemic and to have a high suspicion for this novel disease.

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Stem cell factor (SCF) is developmentally critical for melanocyte migration, differentiation, and survival. Recently, SCF expression in hair shaft progenitor cells has been shown to be absolutely required for the pigmentation in hair shafts, as evidenced by the complete loss of hair pigmentation in mice without SCF in these epithelial cells. Interestingly, this fully disruption of hair pigmentation only targets melanogenic mature monocytes in the upper hair bulb, but not melanocyte precursors below. This shows an important role of SCF in the determination of mature melanocytes to their destination. Here we report that the skin pigmentation in the dermis layer appears to follow the same mechanism for the distribution of dermal melanocytes. We employed multiple cell-type specific Scf knockout mice to characterize the sources and contribution of SCF to dermal pigmentation. Our results show that dermal melanocytes are also sustained by SCF. However, in contrast to hair pigmentation, dermal pigmentation appears to be supported by SCF expression in a selective population of dermal cells. This study reveals a faithful distribution of melanogenic melanocytes in distinct skin compartments guided by selective populations of SCF expressing cells. Our findings suggest that manipulation of SCF expression in the skin cells might be a potential target to manage hyper-or hypo-pigmented skin manifestations in clinic.