4 research outputs found
Binding of Tetracycline and Chlortetracycline to the Enzyme Trypsin: Spectroscopic and Molecular Modeling Investigations
Tetracycline (TC) and chlortetracycline (CTC) are common members of the widely used veterinary drug tetracyclines, the residue of which in the environment can enter human body, being potentially harmful. In this study, we establish a new strategy to probe the binding modes of TC and CTC with trypsin based on spectroscopic and computational modeling methods. Both TC and CTC can interact with trypsin with one binding site to form trypsin-TC (CTC) complex, mainly through van der Waals' interactions and hydrogen bonds with the affinity order: TC>CTC. The bound TC (CTC) can result in inhibition of trypsin activity with the inhibition order: CTC>TC. The secondary structure and the microenvironment of the tryptophan residues of trypsin were also changed. However, the effect of CTC on the secondary structure content of trypsin was contrary to that of TC. Both the molecular docking study and the trypsin activity experiment revealed that TC bound into S1 binding pocket, competitively inhibiting the enzyme activity, and CTC was a non-competitive inhibitor which bound to a non-active site of trypsin, different from TC due to the Cl atom on the benzene ring of CTC which hinders CTC entering into the S1 binding pocket. CTC does not hinder the binding of the enzyme substrate, but the CTC-trypsin-substrate ternary complex can not further decompose into the product. The work provides basic data for clarifying the binding mechanisms of TC (CTC) with trypsin and can help to comprehensively understanding of the enzyme toxicity of different members of tetracyclines in vivo
Quarantine experience of healthcare workers in close contact with COVID-19 patients in China: a qualitative study
Background This study investigated the experiences of front-line healthcare workers who had been in close contact with COVID-19 patients and had been quarantined in order to provide guidance on quarantine measures with more humanistic care when dealing with future public health emergencies.Methods We conducted a qualitative study using semistructured, qualitative, in-depth interviews between April and June 2022. The interviews were recorded and transcribed, followed by a thematic analysis. The study followed the Standards for Reporting Qualitative Research.Results This study identified the following four themes: (1) personal psychological changes, (2) increased reflection on life and work during quarantine, (3) the important role of others’ support and (4) different types of demands during quarantine and isolation. Each theme is supported by several subthemes that further illustrate the participants’ experiences.Conclusions Quarantine of close contacts is necessary to prevent outbreaks. Front-line doctors and nurses are at a greater risk of COVID-19 infection than others. The results showed the psychological reactions of ordinary close contacts, and the unique feelings and experiences of doctors and nurses during the epidemic. Therefore, future research should cooperate with multiple departments to assess their needs, provide them with individualised care and love and give them incentives in order to reduce their psychological burden, improve their quality of life and allow them to engage in healthcare with a healthy mind