RESUMEN
Different studies suggest an impact of biofilms on carcinogenic lesion formation in varying human tissues. However, the mechanisms of cancer formation are difficult to examine in vivo as well as in vitro. Cell culture approaches, in most cases, are unable to keep a bacterial steady state without any overgrowth. In our approach, we aimed to develop an immunocompetent 3D tissue model which can mitigate bacterial outgrowth. We established a three-dimensional (3D) co-culture of human primary fibroblasts with pre-differentiated THP-1-derived macrophages on an SIS-muc scaffold which was derived by decellularisation of a porcine intestine. After establishment, we exposed the tissue models to define the biofilms of the Pseudomonas spec. and Staphylococcus spec. cultivated on implant mesh material. After 3 days of incubation, the cell culture medium in models with M0 and M2 pre-differentiated macrophages presented a noticeable turbidity, while models with M1 macrophages presented no noticeable bacterial growth. These results were validated by optical density measurements and a streak test. Immunohistology and immunofluorescent staining of the tissue presented a positive impact of the M1 macrophages on the structural integrity of the tissue model. Furthermore, multiplex ELISA highlighted the increased release of inflammatory cytokines for all the three model types, suggesting the immunocompetence of the developed model. Overall, in this proof-of-principle study, we were able to mitigate bacterial overgrowth and prepared a first step for the development of more complex 3D tissue models to understand the impact of biofilms on carcinogenic lesion formation.
RESUMEN
BACKGROUND: Prior to undergoing radioiodine therapy (RIT), patients regularly have concerns about isolation on the ward (mandatory for RIT for at least 48 hours in Germany due to radiation protection legislation) as well as fear of the presence of radioactive substances. In this study, these fears were investigated before and after RIT. METHODS: A questionnaire was developed for completion both before and after radioiodine therapy. Questions included: (i) "Are you afraid of a therapy with radioactive substances?" (ii) "Do you have reservations about contact with radioactive substances?" and (iii) "Are you anxious about isolation?" Possible answers were made in a qualitative representation using a scale of 1-4 (4=full agreement, 3=mostly agreement, 2=partial agreement, and 1=no agreement). Further questions included, for example, sources of information used prior to therapy. A total of 209 patients treated by single or preplanned multiple RIT were surveyed over a period of 8 months (return 109). Analysis was done in subgroups according to age, education, disease, and number of RITs. RESULTS: Question 1, "Are you afraid of a therapy with radioactive substances?" showed a similar statistically relevant decline in each subgroup (p<0.05), except for patients with multiple RIT (p=0.81). Asked about the handling of radioactive substances and their perception about the safety in this regard, the entire collective showed a highly statistically significant (p<0.01) decrease with little variability between the groups. The question concerning fear of isolation resulted in a significant decrease (p<0.05) in all subgroups, except for patients with multiple RIT (p=0.13). Analysis of sources of information before RIT showed that older patients preferred printed material and rarely used online resources, while younger patients used the internet more frequently, in addition to printed materials. Finally, most patients would undergo radioiodine therapy again (medical indication provided), with 54% fully agreeing and only 4% not agreeing. CONCLUSIONS: The survey demonstrates a reduction in concerns about nuclear radiation, use of unsealed radioactive materials, and isolation on the ward after RIT. Surprisingly, concerns rise again before a subsequent therapy.
