Transcriptome profiling is an indispensable tool in advancing the understanding of single cell biology, but depends upon methods capable of isolating mRNA at the spatial resolution of a single cell. Current capture methods lack sufficient spatial resolution to isolate mRNA from individual in vivo resident cells without damaging adjacent tissue. Because of this limitation, it has been difficult to assess the influence of the microenvironment on the transcriptome of individual neurons. Here, we engineered a Transcriptome In Vivo Analysis (TIVA)-tag, which upon photoactivation enables mRNA capture from single cells in live tissue. Using the TIVA-tag in combination with RNA-seq to analyze transcriptome variance among single dispersed cells and in vivo resident mouse and human neurons, we show that the tissue microenvironment shapes the transcriptomic landscape of individual cells. The TIVA methodology provides the first noninvasive approach for capturing mRNA from single cells in their natural microenvironment.

Background Coronavirus disease 2019 (COVID-19) is a global pandemic that had affected more than eight million people worldwide by June 2020. Given the importance of the presence of diabetes mellitus (DM) for host immunity, we retrospectively evaluated the clinical characteristics and outcomes of moderate-to-severe COVID-19 in patients with diabetes. Methods We conducted a multi-center observational study of 1,082 adult inpatients (aged ≥18 years) who were admitted to one of five university hospitals in Daegu because of the severity of their COVID-19-related disease. The demographic, laboratory, and radiologic findings, and the mortality, prevalence of severe disease, and duration of quarantine were compared between patients with and without DM. In addition, 1:1 propensity score (PS)-matching was conducted with the DM group. Results Compared with the non-DM group ( n =847), patients with DM ( n =235) were older, exhibited higher mortality, and required more intensive care. Even after PS-matching, patients with DM exhibited more severe disease, and DM remained a prognostic factor for higher mortality (hazard ratio, 2.40; 95% confidence interval, 1.38 to 4.15). Subgroup analysis revealed that the presence of DM was associated with higher mortality, especially in older people (≥70 years old). Prior use of a dipeptidyl peptidase-4 inhibitor or a renin-angiotensin system inhibitor did not affect mortality or the clinical severity of the disease. Conclusion DM is a significant risk factor for COVID-19 severity and mortality. Our findings imply that COVID-19 patients with DM, especially if elderly, require special attention and prompt intensive care.

SummarySensory axons degenerate following separation from their cell body, but partial injury to peripheral nerves may leave the integrity of damaged axons preserved. We show that an endogenous ligand for the natural killer (NK) cell receptor NKG2D, Retinoic Acid Early 1 (RAE1), is re-expressed in adult dorsal root ganglion neurons following peripheral nerve injury, triggering selective degeneration of injured axons. Infiltration of cytotoxic NK cells into the sciatic nerve by extravasation occurs within 3 days following crush injury. Using a combination of genetic cell ablation and cytokine-antibody complex stimulation, we show that NK cell function correlates with loss of sensation due to degeneration of injured afferents and reduced incidence of post-injury hypersensitivity. This neuro-immune mechanism of selective NK cell-mediated degeneration of damaged but intact sensory axons complements Wallerian degeneration and suggests the therapeutic potential of modulating NK cell function to resolve painful neuropathy through the clearance of partially damaged nerves.

We fabricated a carbon nanotube (CNT)/ polydimethylsiloxane (PDMS) composite-based dry ECG electrode that can be readily connected to conventional ECG devices, and showed its long-term wearable monitoring capability and robustness to motion and sweat. While the dispersion of CNTs in PDMS is challenging, we optimized the process to disperse untreated CNTs within PDMS by mechanical force only. The electrical and mechanical characteristics of the CNT/PDMS electrode were tested according to the concentration of CNTs and its thickness. The performances of ECG electrodes were evaluated by using 36 types of electrodes which were fabricated with different concentrations of CNTs, and with a differing diameter and thickness. The ECG signals were obtained by using electrodes of diverse sizes to observe the effects of motion and sweat, and the proposed electrode was shown to be robust to both factors. The CNT concentration and diameter of the electrodes were critical parameters in obtaining high-quality ECG signals. The electrode was shown to be biocompatible from the cytotoxicity test. A seven-day continuous wearability test showed that the quality of the ECG signal did not degrade over time, and skin reactions such as itching or erythema were not observed. This electrode could be used for the long-term measurement of other electrical biosignals for ubiquitous health monitoring including EMG, EEG, and ERG.

The outcome of coronavirus disease 2019 (COVID-19) is associated with organ damage; however, the information about the relationship between acute kidney injury (AKI) and COVID-19 is still rare. We evaluated the clinical features and prognosis of COVID-19 patients with AKI according to the AKI severity. Medical data of hospitalized COVID-19 patients in two university-based hospitals during an outbreak in Daegu, South Korea, were retrospectively analyzed. AKI and its severity were defined according to the Acute Kidney Injury Network. Of the 164 hospitalized patients with COVID-19, 30 patients (18.3%) had AKI; 14, 4, and 12 patients had stage 1, 2, and 3, respectively. The median age was significantly higher in AKI patients than in non-AKI patients (75.5 vs. 67.0 years, p = 0.005). There were 17 deaths (56.7%) among AKI patients; 4 (28.6%), 1 (25.0%), and 12 (100.0%), respectively. In-hospital mortality was higher in AKI patients than in non-AKI patients (56.7% vs. 20.8%, p < 0.001). After adjusting for potential confounding factors, stage 3 AKI was associated with higher mortality than either non-AKI or stage 1 AKI (hazard ratio (HR) = 3.62 (95% confidence interval (CI) = 1.75–7.48), p = 0.001; HR = 15.65 (95% CI = 2.43–100.64), p = 0.004). Among the AKI patients, acute respiratory distress syndrome and low serum albumin on admission were considered independent risk factors for stage 3 AKI (both p < 0.05). Five patients with stage 3 AKI underwent dialysis and eventually died. In conclusion, COVID-19 patients with severe AKI had fatal outcomes.

mbulatory 24-h blood pressure (BP) is superior to office BP in relation to advanced hypertensive target organ damage and cardiovascular outcome. 1,2 Furthermore, it has been found that BP variability is associated with organ damage independently on the 24-h mean BP values. 3 In addition, the 24-h BP standard deviation (SD), which is a BP variability index, has been shown to be related to the progression of organ damage over the years. 4,5 It has repeatedly been shown that this phenomenon may have clinical relevance because hypertensive patients with similar 24-h mean BP values have a greater comprehensive score for organ damage when their BP variability is greater. Circulation Journal Vol.72, February 2008So, the identification of increased BP variability by ambulatory monitoring may be one way of detecting the high-risk subject among hypertensive patients.However, the exact mechanisms underlying the link between BP variability and cardiovascular risk are, as yet, unclear. Various mechanisms may be involved in the association between BP variability and cardiovascular disease. In addition to augmented mechanical stress on the cardiovascular system, increased variability of blood flow by augmented BP variability increases sheer stress on endothelial cells. 6,7 Sheer stress-induced platelet activation and subsequent hypercoagulability may lead to cardiovascular events. Neurohumoral activation, which is increased in those with increased BP variability, may also increase the risk for cardiovascular disease.One of the mechanisms explaining the relationship between BP variability and target organ damage is inflammatory response. There is some experimental evidence suggesting that elevated BP and BP variability may promote endothelial expression of cytokines and stimulate inflammation. 8 However, the exact association between BP variability and inflammation in hypertensive subjects has not yet been evaluated. We designed this study to investigate the link between BP variability and inflammation in hypertensive patients. Background Blood pressure (BP) variability has been reported to be associated with hypertensive target organ damage and cardiovascular events. However, the exact mechanism linking BP variability and organ damage is uncertain. This study was designed to investigate the association between BP variability and inflammatory marker in hypertensive patients. Methods and ResultsFifty-two hypertensive patients (28 men, 55.9±1.5 years) completed 24-h ambulatory BP monitoring. Inflammatory markers were evaluated by measuring plasma levels of interleukin (IL)-6, tumor necrosis factor (TNF)-by enzyme-linked immunosorbent assay and high sensitive C-reactive protein (hs-CRP) by particle-enhanced light-scattering immunoassay. BP variability was obtained by calculating within-subject standard deviation (SD) and coefficient of variation of BP. Subjects were grouped into tertiles according to IL-6, TNF-, and hs-CRP levels. A significant association between ambulatory BP and TNF-level was identified (P for trend =0.011). In...

Summary A number of mitochondrial diseases arise from Single Nucleotide Variant (SNV) accumulation in multiple mitochondria. Here we present a method for identification of variants present at the single mitochondrion level in individual mouse and human neuronal cells allowing for extremely high resolution study of mitochondrial mutation dynamics. We identified extensive heteroplasmy between individual mitochondrion, along with three high confidence variants in mouse and one in human that were present in multiple mitochondria across cells. The pattern of variation revealed by single mitochondrion data shows surprisingly pervasive levels of heteroplasmy in inbred mice. Distribution of SNV loci suggests inheritance of variants across generations resulting in Poisson jackpot lines with large SNV load. Comparison of human and mouse variants suggests that the two species might employ distinct modes of somatic segregation. Single mitochondrion resolution revealed mitochondria mutational dynamics that we hypothesize to affect risk probabilities for mutations reaching disease thresholds.

No abstract