Cartilage immunoprivilege depends on donor source and lesion location

The ability to repair damaged cartilage is a major goal of musculoskeletal tissue engineering. Allogeneic (same species, different individual) or xenogeneic (different species) sources can provide an attractive source of chondrocytes for cartilage tissue engineering, since autologous (same individual) cells are scarce. Immune rejection of non-autologous hyaline articular cartilage has seldom been considered due to the popular notion of “cartilage immunoprivilege.” The objective of this study was to determine the suitability of allogeneic and xenogeneic engineered neocartilage tissue for cartilage repair. To address this, scaffold-free tissue engineered articular cartilage of syngeneic (same genetic background), allogeneic, and xenogeneic origin were implanted into two different locations of the rabbit knee (n=3 per group/location). Xenogeneic engineered cartilage and control xenogeneic chondral explants provoked profound innate inflammatory and adaptive cellular responses, regardless of transplant location. Cytological quantification of immune cells showed that, while allogeneic neocartilage elicited an immune response in the patella, negligible responses were observed when implanted into the trochlea; instead the responses were comparable to microfracture-treated empty defect controls. Allogeneic neocartilage survived within the trochlea implant site and demonstrated graft integration into the underlying bone. In conclusion, the knee joint cartilage does not represent an immune privileged site, strongly rejecting xenogeneic but not allogeneic chondrocytes in a location-dependent fashion. This difference in location-dependent survival of allogeneic tissue may be associated with proximity to the synovium

Emergence, longevity and fecundity of Trissolcus basalis and Telenomus podisi after cold storage in the pupal stage Emergência, longevidade e fecundidade de Trissolcus basalis e Telenomus podisi após estocagem no estágio pupal

Pupae of Trissolcus basalis (Wollaston) and Telenomus podisi Ashmead (Hymenoptera: Scelionidae) were stored at 12&ordm;C and 15&ordm;C for 120-210 days, after different periods of parasitism at 18&ordm;C in order to evaluate adult emergence, longevity and ovipositional capacity. There was no emergence of adults at 12&ordm;C. The rate of emergence of parasitoids transferred to 15&ordm;C at the beginning of the pupal stage was 1.5% and 26.3%, for T. basalis and T. podisi respectively, whereas those parasitoids transferred one day before the expected date of emergence at 18&ordm;C showed 86.4% of emergence for T. basalis and 59.9% for T. podisi. Mean adult longevity was also significantly lower when pupae were transferred to 15&ordm;C at the beginning of the pupal stage. Females emerged after storage and maintained for 120 to 210 days at 15&ordm;C parasitized host eggs after transference to 25&ordm;C; however, fecundity of T. podisi was reduced in about 80% after cold storage.<br>Pupas de Trissolcus basalis (Wollaston) e Telenomus podisi Ashmead (Hymenoptera: Scelionidae) armazenadas a 12&ordm;C e 15&ordm;C por 120 a 210 dias, após diferentes períodos de parasitismo a 18&ordm;C, foram avaliadas quanto à emergência, longevidade e capacidade de parasitismo dos adultos. Não houve emergência de adultos a 12&ordm;C. Os índices de emergência de parasitóides transferidos a 15&ordm;C no início do estágio pupal foram 1,5% e 26,3%, em T. basalis e T. podisi, respectivamente, enquanto os transferidos um dia antes da data prevista para a emergência dos adultos a 18&ordm;C apresentaram índices de emergência de 86,4% em T. basalis e 59,9% em T. podisi. De forma semelhante, a longevidade média dos adultos foi significativamente menor quando a transferência para 15&ordm;C foi realizada no início do estágio pupal. Fêmeas emergidas após estocagem das pupas e mantidas por 120 a 210 dias a 15&ordm;C parasitaram ovos hospedeiros após transferência para 25&ordm;C; no entanto, a fecundidade de T. podisi foi reduzida em cerca de 80% quando mantida em baixa temperatura

Outcomes from elective colorectal cancer surgery during the SARS‐CoV‐2 pandemic

Aim This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic. Method This was an international cohort study of patients undergoing elective resection of colon or rectal cancer without preoperative suspicion of SARS-CoV-2. Centres entered data from their first recorded case of COVID-19 until 19 April 2020. The primary outcome was 30-day mortality. Secondary outcomes included anastomotic leak, postoperative SARS-CoV-2 and a comparison with prepandemic European Society of Coloproctology cohort data. Results From 2073 patients in 40 countries, 1.3% (27/2073) had a defunctioning stoma and 3.0% (63/2073) had an end stoma instead of an anastomosis only. Thirty-day mortality was 1.8% (38/2073), the incidence of postoperative SARS-CoV-2 was 3.8% (78/2073) and the anastomotic leak rate was 4.9% (86/1738). Mortality was lowest in patients without a leak or SARS-CoV-2 (14/1601, 0.9%) and highest in patients with both a leak and SARS-CoV-2 (5/13, 38.5%). Mortality was independently associated with anastomotic leak (adjusted odds ratio 6.01, 95% confidence interval 2.58–14.06), postoperative SARS-CoV-2 (16.90, 7.86–36.38), male sex (2.46, 1.01–5.93), age >70 years (2.87, 1.32–6.20) and advanced cancer stage (3.43, 1.16–10.21). Compared with prepandemic data, there were fewer anastomotic leaks (4.9% versus 7.7%) and an overall shorter length of stay (6 versus 7 days) but higher mortality (1.7% versus 1.1%). Conclusion Surgeons need to further mitigate against both SARS-CoV-2 and anastomotic leak when offering surgery during current and future COVID-19 waves based on patient, operative and organizational risks