Increased Total Antioxidant Capacity Value Improves Survival of Fat Grafts in a Rat Model.

BACKGROUND: While studies aiming to increase fat graft survival continue, in this study, we aimed to investigate the effects of different antioxidants on total antioxidant capacity and their effect on graft survival. METHODS: Thirty-two male Wistar rats were divided into four equally sized groups, including a control group and three antioxidant groups receiving either Melatonin (10mg/kg), Zinc (2mg/kg), or Vitamin E and C (100mg/kg). Autologous fat grafts (1.7± 0.4gr) were transferred to the dorsal subcutaneous region, and total antioxidant capacity was measured on day 0 and 1, week 1 and monthly until the third month. Transferred graft volume and mass (1.3± 0.4gr) were measured using the liquid overflow method and precision scales at the end of the study. Routine hematoxylin-eosin staining and immunohistochemistry against perilipin were performed for semiqualitative analysis and h-score for viable adipose cells, respectively. RESULTS: Collected fat grafts measured significantly less in weight and volume and the survival rate was lower in the control group (p<0.01). Control group exhibited a reduction in TAC, while all groups receiving antioxidants had an increase in TAC during the first week (p=0.02, 0.008, and 0.004 for melatonin, zinc, and vitamins, respectively). Immunohistochemistry of the antioxidant group demonstrated a statistically significant excess and reactivity of cells staining with perilipin antibodies. CONCLUSIONS: In this animal study, the beneficial effect of antioxidants on fat graft survival can be related to the significant increase in TAC following the first week of their administration.

Subacute THYROiditis Related to SARS-CoV-2 VAccine and Covid-19 (THYROVAC Study): A Multicenter Nationwide Study.

CONTEXT: The aims of the study are to compare characteristics of subacute thyroiditis (SAT) related to different etiologies, and to identify predictors of recurrence of SAT and incident hypothyroidism. METHODS: This nationwide, multicenter, retrospective cohort study included 53 endocrinology centers in Turkey. The study participants were divided into either COVID-19-related SAT (Cov-SAT), SARS-CoV-2 vaccine-related SAT (Vac-SAT), or control SAT (Cont-SAT) groups. RESULTS: Of the 811 patients, 258 (31.8%) were included in the Vac-SAT group, 98 (12.1%) in the Cov-SAT group, and 455 (56.1%) in the Cont-SAT group. No difference was found between the groups with regard to laboratory and imaging findings. SAT etiology was not an independent predictor of recurrence or hypothyroidism. In the entire cohort, steroid therapy requirement and younger age were statistically significant predictors for SAT recurrence. C-reactive protein measured during SAT onset, female sex, absence of antithyroid peroxidase (TPO) positivity, and absence of steroid therapy were statistically significant predictors of incident (early) hypothyroidism, irrespective of SAT etiology. On the other hand, probable predictors of established hypothyroidism differed from that of incident hypothyroidism. CONCLUSION: Since there is no difference in terms of follow-up parameters and outcomes, COVID-19- and SARS-CoV-2 vaccine-related SAT can be treated and followed up like classic SATs. Recurrence was determined by younger age and steroid therapy requirement. Steroid therapy independently predicts incident hypothyroidism that may sometimes be transient in overall SAT and is also associated with a lower risk of established hypothyroidism.

Superior Epididymal Artery-Based Paraepididymal Adipofascial Flap: An Experimental Adipofascial Flap Model in the Rat.

BACKGROUND: Flap surgery is widely performed in reconstructive surgery. Experimental research is vital to improve flap viability. However, the number of flap models for animals is still limited. In this study, we define a new adipofascial flap in rats that can be used to investigate pedicled flap and/or adipofascial flap physiology. METHODS: Eight Wistar male rats were used. Under deep anesthesia, paraepididymal adipofascial flaps were harvested. Flap perfusion was assessed using a near-infrared fluorescence imaging system. The length of the flap and the diameter of the flap pedicle were measured. RESULTS: All animals (n = 8) had sufficient sizes of paraepididymal fat pad, and no animals were lost. The only postoperative complication was testicular hematoma, which was observed in 2 animals. The maximum length of the harvested paraepididymal adipofascial flap was 9.7 cm with a mean of 6.6 cm. The maximum width of the flap was 3.3 cm with a mean of 2.6 cm. The mean pedicle diameter of the paraepididymal adipofascial flap was 1.1 mm. Near-infrared fluorescence imaging revealed adequate perfusion in all flaps. CONCLUSIONS: The number of reported adipofascial flap models in animals is low, and they are mostly limited to flaps based on epigastric vessels. Superior epididymal artery-based paraepididymal adipofascial flap can be used as a pedicled flap model for studies focusing on adipofascial and/or pedicled flap physiology. Uncomplicated surgical technique and short operative time make this flap a valuable alternative to other flap models.