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The highly infectious disease COVID-19 caused by the Betacoronavirus SARS-CoV-2 poses a severe threat to humanity and demands the redirection of scientific efforts and criteria to organized research projects. The international COVID19-NMR consortium seeks to provide such new approaches by gathering scientific expertise worldwide. In particular, making available viral proteins and RNAs will pave the way to understanding the SARS-CoV-2 molecular components in detail. The research in COVID19-NMR and the resources provided through the consortium are fully disclosed to accelerate access and exploitation. NMR investigations of the viral molecular components are designated to provide the essential basis for further work, including macromolecular interaction studies and high-throughput drug screening. Here, we present the extensive catalog of a holistic SARS-CoV-2 protein preparation approach based on the consortium's collective efforts. We provide protocols for the large-scale production of more than 80% of all SARS-CoV-2 proteins or essential parts of them. Several of the proteins were produced in more than one laboratory, demonstrating the high interoperability between NMR groups worldwide. For the majority of proteins, we can produce isotope-labeled samples of HSQC-grade. Together with several NMR chemical shift assignments made publicly available on covid19-nmr.com , we here provide highly valuable resources for the production of SARS-CoV-2 proteins in isotope-labeled form., Competing Interests: CH was employed by Signals GmbH & Co. KG. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Altincekic, Korn, Qureshi, Dujardin, Ninot-Pedrosa, Abele, Abi Saad, Alfano, Almeida, Alshamleh, de Amorim, Anderson, Anobom, Anorma, Bains, Bax, Blackledge, Blechar, Böckmann, Brigandat, Bula, Bütikofer, Camacho-Zarco, Carlomagno, Caruso, Ceylan, Chaikuad, Chu, Cole, Crosby, de Jesus, Dhamotharan, Felli, Ferner, Fleischmann, Fogeron, Fourkiotis, Fuks, Fürtig, Gallo, Gande, Gerez, Ghosh, Gomes-Neto, Gorbatyuk, Guseva, Hacker, Häfner, Hao, Hargittay, Henzler-Wildman, Hoch, Hohmann, Hutchison, Jaudzems, Jović, Kaderli, Kalniņš, Kaņepe, Kirchdoerfer, Kirkpatrick, Knapp, Krishnathas, Kutz, zur Lage, Lambertz, Lang, Laurents, Lecoq, Linhard, Löhr, Malki, Bessa, Martin, Matzel, Maurin, McNutt, Mebus-Antunes, Meier, Meiser, Mompeán, Monaca, Montserret, Mariño Perez, Moser, Muhle-Goll, Neves-Martins, Ni, Norton-Baker, Pierattelli, Pontoriero, Pustovalova, Ohlenschläger, Orts, Da Poian, Pyper, Richter, Riek, Rienstra, Robertson, Pinheiro, Sabbatella, Salvi, Saxena, Schulte, Schiavina, Schwalbe, Silber, Almeida, Sprague-Piercy, Spyroulias, Sreeramulu, Tants, Tārs, Torres, Töws, Treviño, Trucks, Tsika, Varga, Wang, Weber, Weigand, Wiedemann, Wirmer-Bartoschek, Wirtz Martin, Zehnder, Hengesbach and Schlundt.)

The current outbreak of the highly infectious COVID-19 respiratory disease is caused by the novel coronavirus SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2). To fight the pandemic, the search for promising viral drug targets has become a cross-border common goal of the international biomedical research community. Within the international Covid19-NMR consortium, scientists support drug development against SARS-CoV-2 by providing publicly available NMR data on viral proteins and RNAs. The coronavirus nucleocapsid protein (N protein) is an RNA-binding protein involved in viral transcription and replication. Its primary function is the packaging of the viral RNA genome. The highly conserved architecture of the coronavirus N protein consists of an N-terminal RNA-binding domain (NTD), followed by an intrinsically disordered Serine/Arginine (SR)-rich linker and a C-terminal dimerization domain (CTD). Besides its involvement in oligomerization, the CTD of the N protein (N-CTD) is also able to bind to nucleic acids by itself, independent of the NTD. Here, we report the near-complete NMR backbone chemical shift assignments of the SARS-CoV-2 N-CTD to provide the basis for downstream applications, in particular site-resolved drug binding studies.

Objectives: Postoperative chylothorax is a serious complication after transthoracic esophagectomy, and is associated with major morbidity due to dehydration and malnutrition. For patients with high-output fistula, re-thoracotomy with ligation of the thoracic duct is the treatment of choice. Radiologic interventional management is an innovative procedure that has the potential to replace surgery in the treatment algorithm., Methods: Four patients with high-output chylous leaks following esophagectomy are presented. Ultrasound-guided lymphangiography with embolization of the thoracic duct and/or disruption of the cisterna chyli was performed to occlude the leakage site. Radiologic interventions and procedure-related outcomes are described in detail., Results: In all four patients, ultrasound-guided lymphangiography of the groin with injection of Lipiodol was able to detect and visualize the leakage site in the lower mediastinum. In three patients, the leak could be successfully occluded by Lipiodol embolization. In one patient, embolization failed and the disruption technique was successfully performed. No procedure-related complications were observed., Conclusions: In case of a postoperative chylothorax, radiologic intervention is feasible and safe. The procedure is indicated for high-output chylous fistulas after esophagectomy, and should be applied early after the diagnosis of this postoperative complication., (©2019 Lambertz R., et al., published by De Gruyter, Berlin/Boston.)

To assess genotoxic burdens from chemicals, it is necessary to relate observations in experimental animals to humans. The success of this extrapolation would be increased by including data on chemical activities in human tissues. Therefore, we have developed techniques to assess DNA damage in human gastric and nasal mucosa (GM, NM) cells. Biopsy samples were obtained during gastroscopy from macroscopically healthy tissue of the stomach or from healthy nasal epithelia during surgery. The specimens were incubated for 30-45 min at 37 degrees C with a digestive solution. We obtained 1.5-8 x 10(6) GM cells and 5-10 x 10(5) NM cells per donor, both with viabilities of 80-95%. The cells were incubated in vitro for 1 hr at 37 degrees C with the test compounds added in their appropriate solvents. In GM cells, we studied N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), sodium dichromate (Na2Cr2O7), nickel sulphate (NiSO4), cadmium sulphate (CdSO4), and lindane. In NM cells, lindane was investigated. Each compound was assessed for DNA damaging activity in cells of at least three different human donor samples using the microgel single cell assay. Similar studies were performed with GM and NM cells obtained from Sprague-Dawley rats. We have found human GM cells to be more sensitive to the genotoxic activity of MNNG than rat GM cells (low effective concentration [LEC] = 0.16 and 0.625 micrograms/ml for human and rat, respectively). Human cells were also more sensitive to the cytotoxic/genotoxic activity of NiSO4 (LEC = 5 and 19 mumoles/ml for human and rat, respectively). CdSO4 was genotoxic in human GM cells (LEC = 0.03-0.125 mumoles/ml), whereas no dose-related genotoxicity was observed in rat GM at concentrations up to 0.5 mumoles/ml. In contrast, approximately equal responses regarding genotoxicity and cytotoxicity were observed in rat and human GM for Na2Cr2O7 (0.25-1 mumoles/ml). Lindane, however, was genotoxic in three out of four rat GM but not in human GM cells (0.5-1 mumoles/ml), whereas it was active in both rat and human NM cells. Together with other recently published in vivo findings, our results with lindane can be interpreted according to a parallelogram approach. In view of possible human exposure situations and the sensitivities of the two target tissues from both species, the data imply that lindane will pose a health risk to humans by inhalation but not by ingestion.

In view of the high incidence of dietary-related tumors, one important research goal is to identify the participating genotoxic carcinogens and the nutritional factors that may counteract their activities. We therefore have further developed a method to assess DNA damage in tumor target tissues of the gastrointestinal tract. Subsequently the prevention of this inducible DNA damage by lactic acid bacteria and by milk products fermented with probiotics was studied as well. The microgel electrophoresis technique was applied to cells of the esophageal, gastric, duodenal, and colonic mucosa. Cells were grouped according to their degree of DNA damage, the simplest measure of which is to discriminate between those with damage (comets) and those without damage. When these cells were isolated from animals treated with a genotoxic carcinogen, N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), and exposed to MNNG for 1-24 hours, it was possible to follow the course of genotoxicity throughout the gastrointestinal tract. After the animals were treated with the lactic acid bacteria under study, it was possible to detect antigenotoxic properties as well. The gavage of 10(10) viable Lactobacillus casei cells in 10 ml of 0.9% NaCl per kilogram body weight immediately before the oral administration of MNNG (5 mg/kg body wt) resulted in a reduction of induced DNA damage in gastric and colonic mucosa cells. A sequential treatment schedule was even more effective: when the animals were treated orally with lactic acid bacteria or yogurt (10 ml/kg body wt) in the morning followed by MNNG (7.5 mg/kg body wt) eight hours later and the colon cells were isolated 16 hours later, the percentages of cells remaining intact were distinctly higher in the combination groups (68 +/- 10 and 68 +/- 19 for L. casei and a "Bio" yogurt, respectively) than in the group receiving only MNNG (45 +/- 17). The effect of heating L. casei was studied and was found to yield less clear-cut effects in preventing genotoxicity. The method is an efficient tool to elucidate antigenotoxic properties of food components in vivo in those target tissues actually afflicted by dietary-related tumors.