SARS-CoV2 hospital surveillance and control system with contact tracing for patients and health care workers at a large reference hospital in Spain during the first wave: An observational descriptive study.

BACKGROUND AND AIMS: During the first peak of the COVID-19 pandemic, the Preventive Medicine Department and the Occupational Health Department at Hospital Clinic de Barcelona (HCB), a large Spanish referral hospital, developed an innovative comprehensive SARS-CoV2 Surveillance and Control System (CoSy-19) in order to preserve patients' and health care workers' (HCWs) safety. We aim to describe the CoSy-19 and to assess the impact in the number of contacts that new cases generated along this time. METHODS: Observational descriptive study of the findings of the activity of contact tracing of all cases received at the HCB during the first peak of COVID-19 in Spain (February 25th-May 3rd, 2020). RESULTS: A team of 204 professionals and volunteers performed 384 in-hospital contact-tracing studies which generated contacts, detecting 298 transmission chains which suggested preventive measures, generated around 22 000 follow-ups and more than 30 000 days of work leave. The number of contacts that new cases generated decreased during the study period. CONCLUSION: Coordination between Preventive Medicine and Occupational Health departments and agile information systems were necessary to preserve non-COVID activity and workers safety.

Acquisition of resistance to butyrate enhances survival after stress and induces malignancy of human colon carcinoma cells.

Acquired resistance to apoptosis by tumor cells remains a major obstacle for cancer treatment, and hence the analysis of resistance to apoptosis constitutes a major goal in the development of antitumoral drugs. We have established a butyrate-resistant human colon adenocarcinoma cell line (BCS-TC2.BR2) from nontumorigenic BCS-TC2 cells to analyze whether the acquisition of such phenotype confers resistance to apoptosis and stress. Although BCS-TC2.BR2 cells exhibited a more differentiated phenotype than the parental BCS-TC2 cells, higher butyrate concentrations remained capable of additionally enhancing their differentiation without inducing apoptosis. Survival rates of BCS-TC2.BR2 cells after glucose deprivation and heat shock were higher than those of parental cells, revealing a stress-resistant phenotype. These findings were accompanied by key differences between parental and butyrate-resistant cells in gene expression profiles and the acquisition of in vivo tumorigenicity. In conclusion, cells gaining resistance to an endogenous physiological modulator of growth, differentiation, and apoptosis concurrently acquired resistance to other agents that influence cell survival.