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Irradiation is widely used to treat brain tumors, and also to create bone marrow (BM) chimeras.BM chimeras are widely used to dissect functions and origin of microglia and blood-derived mononuclear cells under homeostatic or pathological conditions. This is facilitated by the fact that microglia survive irradiation and are thus regarded radio-resistant. In this study, we tested whether microglia are indeed radio-resistant and looked for potential mechanisms that might explain this phenomenon. We analyzed the radio-resistance of microglia independently of their physiological brain environment compared to other mononuclear cells from spleen and brain after X-irradiation with 7 Gy or 30 Gy. Furthermore, we investigated long-term effects of X-irradiation on microglia using organotypic hippocampal slice cultures (OHSCs). We found a significant higher survival rate of isolated microglia 4 hr after X-irradiation with 30 Gy accompanied by a decreased proliferation rate. Investigations of apoptosis-related genes revealed no regulation of a specific antiapoptotic pathway but ataxia telangiectasia mutated (ATM), a DNA-repair-related gene, was significantly upregulated in isolated microglia 4 hr after 30 Gy. Irradiation of OHSCs with 7 and 30 Gy revealed a highly and significantly decreased cell number, morphological changes and an increase in migration velocity of microglia. Furthermore, cell loss, increased soma size and process length of microglia was also found in BM chimeras irradiated with 9.5 Gy 5 weeks after irradiation. Here, we present new evidence implying that microglia are not a homogeneous population of radio-resistant cells and report on long-term alterations of microglia that survived irradiation.

video-based virtual visits are a growing aspect of surgical care and have dramatically increased in the setting of the coronavirus disease 2019 (COVID-19) pandemic.OBJECTIVE To evaluate the outcomes of all-cause 30-day hospital encounter proportion among patients who have a postdischarge video-based virtual visit follow-up compared with in-person follow-up.DESIGN, SETTING, AND PARTICIPANTS Randomized, active, controlled noninferiority trial in an urban setting, including patients from a small community hospital and a large, tertiary care hospital. Patients who underwent minimally invasive appendectomy or cholecystectomy by a group of surgeons who cover emergency general surgery at these 2 hospitals were included. Patients undergoing elective and nonelective procedures were included.INTERVENTIONS Patients were randomized in a 2:1 fashion to video-based virtual visit or in-person visit. MAIN OUTCOMES AND MEASURESThe primary outcome is the percentage of patients with 30-day hospital encounter, and we hypothesized that there would not be a significant increase in the 30-day hospital encounter proportion for patients who receive video-based virtual postdischarge care compared with patients who receive standard (in-person) care. Hospital encounter includes emergency department visit, observation, or inpatient admission.RESULTS A total of 1645 patients were screened; 289 patients were randomized to the virtual group and 143 to the in-person group. Fifty-three patients crossed over to the in-person follow-up group. The percentage of patients who had a hospital encounter was noninferior for virtual visits (12.8% vs 13.3% for in-person, Δ 0.5% with 1-sided 95% CI, −ϱ to 5.2%). The amount of time patients spent with the clinician (mean of 8.4 minutes virtual vs 7.8 minutes in-person; P = .30) was not different, but the median overall postoperative visit time was 27.5 minutes shorter (95% CI, −33.5 to −24.0). CONCLUSIONS AND RELEVANCEPostdischarge video-based virtual visits did not increase hospital encounter proportions and provided shorter overall time commitment but equal time with the surgical team member. This information will help surgeons and patients feel more confident in using video-based virtual visits.

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Cancer research requires models closely resembling the tumor in the patient. Human tissue cultures can overcome interspecies limitations of animal models or the loss of tissue architecture in in vitro models. However, analysis of tissue slices is often limited to histology. Here, we demonstrate that slices are also suitable for whole transcriptome sequencing and present a method for automated histochemistry of whole slices. Tumor and peritumoral tissue from a patient with glioblastoma was processed to slice cultures, which were treated with standard therapy including temozolomide and X-irradiation. Then, RNA sequencing and automated histochemistry were performed. RNA sequencing was successfully accomplished with a sequencing depth of 243 to 368 x 106 reads per sample. Comparing tumor and peritumoral tissue, we identified 1888 genes significantly downregulated and 2382 genes upregulated in tumor. Treatment significantly downregulated 2017 genes, whereas 1399 genes were upregulated. Pathway analysis revealed changes in the expression profile of treated glioblastoma tissue pointing towards downregulated proliferation. This was confirmed by automated analysis of whole tissue slices stained for Ki67. In conclusion, we demonstrate that RNA sequencing of tissue slices is possible and that histochemical analysis of whole tissue slices can be automated which increases the usability of this preclinical model.