Amplified Cold Transduction in Native Nociceptors by M-Channel Inhibition

Topically applied camphor elicits a sensation of cool, but nothing is known about how it affects cold temperature sensing. We found that camphor sensitizes a subpopulation of menthol-sensitive native cutaneous nociceptors in the mouse to cold, but desensitizes and partially blocks heterologously expressed TRPM8(transient receptor potential cation channel subfamily M member 8). In contrast, camphor reduces potassium outward currents in cultured sensory neurons and, in cold nociceptors, the cold-sensitizing effects of camphor and menthol are additive. Using a membrane potential dye-based screening assay and heterologously expressed potassium channels, we found that the effects of camphor are mediated by inhibition of K(v)7.2/3 channels subtypes that generate the M-current in neurons. In line with this finding, the specific M-current blocker XE991 reproduced the cold-sensitizing effect of camphor in nociceptors. However, the M-channel blocking effects of XE991 and camphor are not sufficient to initiate cold transduction but require a cold-activated inward current generated by TRPM8. The cold-sensitizing effects of XE991 and camphor are largest in high-threshold cold nociceptors. Low-threshold corneal cold thermoreceptors that express high levels of TRPM8 and lack potassium channels are not affected by camphor. We also found that menthol-like camphor-potently inhibits K(v)7.2/3 channels. The apparent functional synergism arising from TRPM8 activation and M-current block can improve the effectiveness of topical coolants and cooling lotions, and may also enhance TRPM8-mediated analgesia

TNFα aggravates detrimental effects of SARS-CoV-2 infection in the liver

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This virus does not only lead to pulmonary infection but can also infect other organs such as the gut, the kidney, or the liver. Recent studies confirmed that severe cases of COVID-19 are often associated with liver damage and liver failure, as well as the systemic upregulation of pro-inflammatory cytokines such as tumor necrosis factor-alpha (TNFα). However, the impact these immune mediators in the liver have on patient survival during SARS-CoV-2 infection is currently unknown. Here, by performing a post-mortem analysis of 45 patients that died from a SARS-CoV-2 infection, we find that an increased expression of TNFA in the liver is associated with elevated mortality. Using publicly available single-cell sequencing datasets, we determined that Kupffer cells and monocytes are the main sources of this TNFα production. Further analysis revealed that TNFα signaling led to the upregulation of pro-inflammatory genes that are associated with an unfavorable outcome. Moreover, high levels of TNFA in the liver were associated with lower levels of interferon alpha and interferon beta. Thus, TNFα signaling in the infected SARS-CoV-2 liver correlates with reduced interferon levels and overall survival time

Intestinal IL-1β Plays a Role in Protecting against SARS-CoV-2 Infection

The intestine is constantly balancing the maintenance of a homeostatic microbiome and the protection of the host against pathogens such as viruses. Many cytokines mediate protective inflammatory responses in the intestine, among them IL-1β. IL-1β is a proinflammatory cytokine typically activated upon specific danger signals sensed by the inflammasome. SARS-CoV-2 is capable of infecting multiple organs, including the intestinal tract. Severe cases of COVID-19 were shown to be associated with a dysregulated immune response, and blocking of proinflammatory pathways was demonstrated to improve patient survival. Indeed, anakinra, an Ab against the receptor of IL-1β, has recently been approved to treat patients with severe COVID-19. However, the role of IL-1β during intestinal SARS-CoV-2 infection has not yet been investigated. Here, we analyzed postmortem intestinal and blood samples from patients who died of COVID-19. We demonstrated that high levels of intestinal IL-1β were associated with longer survival time and lower intestinal SARS-CoV-2 RNA loads. Concurrently, type I IFN expression positively correlated with IL-1β levels in the intestine. Using human intestinal organoids, we showed that autocrine IL-1β sustains RNA expression of IFN type I by the intestinal epithelial layer. These results outline a previously unrecognized key role of intestinal IL-1β during SARS-CoV-2 infection

Is There an Optimal Definition for a Positive Circumferential Resection Margin in Locally Advanced Esophageal Cancer?

<jats:title>Abstract</jats:title><jats:p>Sewage sludge is formed during wastewater treatment and in recent years, the amount of sewage sludge increased rapidly all over the world. This sewage sludge is attractive for usage in agriculture as an inexpensive nitrogen and phosphorus fertilizer. However, there is only very limited knowledge about the spectrum of organic pollutants that might occur in sewage sludge and is probably posing a threat to the environment. We therefore conducted GC–MS based non-target screening analyses in order to identify a wide spectrum of organic contaminants in sludge samples from several wastewater treatment plants and to figure out corresponding finger-prints of pollution. The plants are located in Germany and China and have various capacities ranging from 35,000 to 1.1 million population equivalents. The special focus was to reveal information on the structural variety of individual organic compounds in sludge samples from the two countries. Several emerging pollutants including some fragrances, pharmaceutical educts, vitaminoids, technical additives were identified accompanied by compounds of biogenic origin. Some of these compounds have rarely been reported as constituents of sewage sludge to date and, consequently, are relevant candidates for more specific assessments including the ecotoxicological long-term effects. Based on the results of this study, it seems mandatory to establish non-target screening analyses on a regularly base as a tool for a comprehensive identification of the variety of anthropogenic organic constituents. Following, such contaminant spectrum can act as basis for further environmental risk assessments as well as to provide individual fingerprints for evaluation of impacts on ecosystems.</jats:p&gt

Clinical Applications of Circulating Tumor Cells and Circulating Tumor DNA as a Liquid Biopsy Marker in Colorectal Cancer

Colorectal cancer (CRC) is the third most commonly diagnosed cancer worldwide. It is a heterogeneous tumor with a wide genomic instability, leading to tumor recurrence, distant metastasis, and therapy resistance. Therefore, adjunct non-invasive tools are urgently needed to help the current classical staging systems for more accurate prognostication and guiding personalized therapy. In recent decades, there has been an increasing interest in the diagnostic, prognostic, and predictive value of circulating cancer-derived material in CRC. Liquid biopsies provide direct non-invasive access to tumor material, which is shed into the circulation; this enables the analysis of circulating tumor cells (CTC) and genomic components such as circulating free DNA (cfDNA), which could provide the key for personalized therapy. Liquid biopsy (LB) allows for the identification of patients with a high risk for disease progression after curative surgery, as well as longitudinal monitoring for disease progression and therapy response. Here, we will review the most recent studies on CRC, demonstrating the clinical potential and utility of CTCs and ctDNA. We will discuss some of the advantages and limitations of LBs and the future perspectives in the field of CRC management

Combined endoscopic-percutaneous treatment of upper gastrointestinal enterocutaneous fistula using vacuum therapy and resorbable plug insertion (Vac-Plug)

Abstract After gastrointestinal resections, leakages can occur, persist despite conventional therapy and result in enterocutaneous fistulae. We developed a combination method using flexible endoscopic techniques to seal the enteric orifice with an absorbable plug in addition to a percutaneously and fistuloscopically guided open-pore film drainage (Vac-Plug method). We retrospectively searched our endoscopy database to identify patients treated with the outlined technique. The clinical and pathological data were assessed, the method analyzed and characterized and the technical and clinical success determined. We identified 14 patients that were treated with the Vac-Plug method (4 females, 10 males with a mean age of 56 years, range 50–74). The patients were treated over a time period of 23 days (range 4–119) in between one to thirteen interventions (mean n = 5). One patient had to be excluded due to short follow-up after successful closure. Seventy-seven percent (10/13) were successfully treated with a median follow-up of 453 days (range 35–1246) thereafter. No treatment related complications occurred during the therapy. The data of the analysis showed that the Vac-Plug therapy is safe and successful in a relevant proportion of the patients. It is easy to learn and to apply and is well tolerated. In our opinion, it is a promising addition to the armamentarium of interventional methods of these difficult to treat patients. Of course, its usefulness must be further validated in larger prospective studies

Differential Contribution of TRPA1, TRPV4 and TRPM8 to Colonic Nociception in Mice

Background Various transient receptor potential (TRP) channels in sensory neurons contribute to the transduction of mechanical stimuli in the colon. Recently, even the cold-sensing menthol receptor TRPM(melastatin)8 was suggested to be involved in murine colonic mechano-nociception. Methods To analyze the roles of TRPM8, TRPA1 and TRPV4 in distension-induced colonic nociception and pain, TRP-deficient mice and selective pharmacological blockers in wild-type mice (WT) were used. Visceromotor responses (VMR) to colorectal distension (CRD) in vivo were recorded and distension/pressure-induced CGRP release from the isolated murine colon ex vivo was measured by EIA. Results Distension-induced colonic CGRP release was markedly reduced in TRPA1-/- and TRPV4-/- mice at 90/150 mmHg compared to WT. In TRPM8-deficient mice the reduction was only distinct at 150 mmHg. Exposure to selective pharmacological antagonists (HC030031, 100 μM; RN1734, 10 μM; AMTB, 10 μM) showed corresponding effects. The unselective TRP blocker ruthenium red (RR, 10 μM) was as efficient in inhibiting distension-induced CGRP release as the unselective antagonists of mechanogated DEG/ENaC (amiloride, 100 μM) and stretch-activated channels (gadolinium, 50 μM). VMR to CRD revealed prominent deficits over the whole pressure range (up to 90 mmHg) in TRPA1-/- and TRPV4-/- but not TRPM8-/- mice; the drug effects of the TRP antagonists were again highly consistent with the results from mice lacking the respective TRP receptor gene. Conclusions TRPA1 and TRPV4 mediate colonic distension pain and CGRP release and appear to govern a wide and congruent dynamic range of distensions. The role of TRPM8 seems to be confined to signaling extreme noxious distension, at least in the healthy colon