Summary Ebola virus (EBOV) causes epidemics with high mortality yet remains understudied due to the challenge of experimentation in high-containment and outbreak settings. Here, we used single-cell transcriptomics and CyTOF-based single-cell protein quantification to characterize peripheral immune cells during EBOV infection in rhesus monkeys. We obtained 100,000 transcriptomes and 15,000,000 protein profiles, finding that immature, proliferative monocyte-lineage cells with reduced antigen-presentation capacity replace conventional monocyte subsets, while lymphocytes upregulate apoptosis genes and decline in abundance. By quantifying intracellular viral RNA, we identify molecular determinants of tropism among circulating immune cells and examine temporal dynamics in viral and host gene expression. Within infected cells, EBOV downregulates STAT1 mRNA and interferon signaling, and it upregulates putative pro-viral genes (e.g., DYNLL1 and HSPA5 ), nominating pathways the virus manipulates for its replication. This study sheds light on EBOV tropism, replication dynamics, and elicited immune response and provides a framework for characterizing host-virus interactions under maximum containment.

HuR is a ubiquitous, RNA binding protein that influences the stability and translation of several cellular mRNAs. Here, we report a novel role for HuR, as a regulator of proteins assembling at the 3= untranslated region (UTR) of viral RNA in the context of hepatitis C virus (HCV) infection. HuR relocalizes from the nucleus to the cytoplasm upon HCV infection, interacts with the viral polymerase (NS5B), and gets redistributed into compartments of viral RNA synthesis. Depletion in HuR levels leads to a significant reduction in viral RNA synthesis. We further demonstrate that the interaction of HuR with the 3= UTR of the viral RNA affects the interaction of two host proteins, La and polypyrimidine tract binding protein (PTB), at this site. HuR interacts with La and facilitates La binding to the 3= UTR, enhancing La-mediated circularization of the HCV genome and thus viral replication. In addition, it competes with PTB for association with the 3= UTR, which might stimulate viral replication. Results suggest that HuR influences the formation of a cellular/viral ribonucleoprotein complex, which is important for efficient initiation of viral RNA replication. Our study unravels a novel strategy of regulation of HCV replication through an interplay of host and viral proteins, orchestrated by HuR. IMPORTANCE Hepatitis C virus (HCV) is highly dependent on various host factors for efficient replication of the viral RNA.Here, we have shown how a host factor (HuR) migrates from the nucleus to the cytoplasm and gets recruited in the protein complex assembling at the 3= untranslated region (UTR) of HCV RNA. At the 3= UTR, it facilitates circularization of the viral genome through interaction with another host factor, La, which is critical for replication. Also, it competes with the host protein PTB, which is a negative regulator of viral replication. Results demonstrate a unique strategy of regulation of HCV replication by a host protein through alteration of its subcellular localization and interacting partners. The study has advanced our knowledge of the molecular mechanism of HCV replication and unraveled the complex interplay between the host factors and viral RNA that could be targeted for therapeutic interventions. Hepatitis C virus (HCV) was discovered in 1989 as a major cause of chronic non-A non-B hepatitis (1). HCV is an enveloped positive-strand RNA virus classified in the Hepacivirus genus within the Flaviviridae family. The single-stranded uncapped 9.6-kb RNA codes for a long polyprotein of ϳ3,000 amino acids which is then processed to structural and nonstructural proteins. The RNA genome is flanked by the 5= and 3= untranslated regions (UTRs), which are essential for translation and replication of the viral RNA. The viral proteins are synthesized by internal ribosome entry site (IRES)-mediated translation. These proteins initiate extensive remodeling of the intracellular membranes to create a detergent-resistant scaffold for viral replication, termed as the "membranous web" (2). The progeny viral genomes a...

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How to cite this article: S. Fareed Ul Hameed, S. Habeeb Mohammed, P. Karuppasamy. Evaluation of peripheral lower limb insufficiency among patients with diabetes mellitus using doppler ultrasound -an prospective study. International Journal of Contemporary Medicine Surgery and Radiology. 2020;5(1):A1-A5. Results: The most common artery involvement was found to be dorsapaedalis artery in 26% of the cases followed by proximal femoral and distal femoral in 18% of the cases whereas there were 12% cases with popliteal artery and distal artery branches involvement. The most common site of lesion involved was proximal femoral artery and dorsapaedalis artery seen in 26% of the cases (both) whereas distal femoral artery (DFA) was found in 10% of the cases, poplitial artery (PA) in 18% of the cases followed by posterior tibial artery (PTA) and anterior tibial artery (ATA) in 8% and 12% of the cases respectively. Conclusion: Peripheral vascular insufficiency was a significant finding in patients having diabetes for 1-10 years. The dorsalispaedis artery was the commonest site of involvement. The normal Doppler study virtually rules out a haemodynamically significant lesion and helps to prevent unnecessary intervention.

Authorship note: RL, CMS, and HC contributed equally to this work. Conflict of interest: MA, KK, BB, and JY are current or former employees of WCCT Global. DRM is an unpaid advisor for WCCT Global. ZBH is an employee of Primity Bio. PFG is an employee of the Parker Institute for Cancer Immunotherapy. KK and JY are employees of ARK Clinical Research. NA is an advisor for January Inc. and Vasognosis and a consultant for MaraBio, and has received research funding support from Alkahest. CMS has equity in and is a scientific advisor for Enable Medicine LLC. SEH has received consultancy fees from Sanofi Pasteur, Lumen, Novavax, and Merck for work unrelated to this report. GPN and DRM have received research funding support from Vaxart Inc. GPN holds patents (US8003312B2 and US8679858B2) related to CyTOF and associated reagents that were used in this study and receives royalties derived from those patents in accordance with Stanford's publicly available distribution agreement.