[Coverage of complex pararectal pelvic defects: role of the free myocutaneous musculus vastus lateralis flap]. / Deckung komplexer pararektaler Beckendefekte: Rolle der freien myokutanen Musculus vastus lateralis Lappenplastik.

BACKGROUND: In the event of an advanced rectal carcinoma, an evisceration with rectal amputation may become necessary. The resulting defects, due to their extent, depth, or local tissue damage from previous surgeries and radiation, can in many cases only be closed through free microvascular tissue transfer. In this case series, we demonstrate the successful combination of a musculocutaneous musculus vastus lateralis flap (MVL) with a direct connection to the superior gluteal artery. MATERIALS AND METHODS: Over a 47-month period, we retrospectively examined 11 cases of patients with dorsal pelvic defects after evisceration and rectal amputation that could not be closed using local or regional means. In cases of extensive defects with deep pararectal wound cavities, all these patients underwent defect coverage through a free myocutaneous MVL flap with a direct vascular anastomosis to the superior gluteal vessels. RESULTS: The mean defect size was 290.0 cm² (SD: 131.2; range: 200-600 cm²). The mean defect depth was 10.5 cm, necessitating MVL flap reconstruction with an average size of 336.3 cm². Three operative revisions were required due to postoperative bleeding. There were no arterial or venous thromboses, and no flap loss occurred. Only one necrosis of a distal flap tip was observed, which could be corrected secondarily by direct suturing. The case-mix evaluation yielded an average value of 24.251 (SD: 21.699; range: 7.036-65.748) points, emphasizing the complexity of the cases. CONCLUSIONS: Our results indicate that a free microvascular MVL flap is a viable therapeutic option for pararectal defects that cannot be closed by local or regional methods. The superior gluteal artery proves to be a safe and sufficient vascular connection. In combination, even extensive defects can be successfully closed.

[Breast implant-associated squamous cell carcinoma: a systematic literature review]. / Brustimplantat assoziiertes Plattenepithelkarzinom (BIA-SCC) ­ eine systematische Literaturübersicht.

BACKGROUND: Breast implant-associated squamous cell carcinoma (BIA-SCC) is being discussed as a distinct malignant tumour entity originating from the implant capsule. The FDA and the ASPS published a safety communication on BIA-SCC in 2022, with a first case report of BIA-SCC having been published in the 1990s. This manuscript summarises the current scientific data on this rare tumour entity. MATERIAL AND METHODS: This systematic literature review from two independent databases includes all publications of cases with histopathologically confirmed BIA-SCC. Data extraction included study design, demographic data, implant information and details regarding diagnosis and treatment. RESULTS: Nineteen cases of BIA-SCC with a mean age of 57±10 years were reported in 16 publications. In most cases, the indication was aesthetic augmentation (n=13). Both silicone (n=11) and saline (n=7) implants with different surfaces (smooth n=3, textured n=3, polyurethane n=1) were used. Symptoms such as unilateral swelling (n=18), pain (n=14) and erythema (n=5) occurred on an average of 23±9 years after implantation. Imaging showed fluid collection (n=8) or a tumour mass (n=4) around the breast implant. The most common surgical treatment was explantation with capsulectomy. Metastasis was described in 6 cases. CONCLUSIONS: BIA-SCC is a malignant tumour entity associated with breast implant capsules. Based on current low-quality data (level of evidence class V), no definitive conclusion regarding correlation and causality of SCC in patients with breast implants can be drawn. There is an urgent need for national and international breast implant and breast cancer registries to obtain valid data on the incidence, pathogenesis and clinical presentation of rare tumour entities.

"I miss my school!": Examining primary and secondary school students' social distancing and emotional experiences during the Covid-19 pandemic.

With the rapid spread of Covid-19, countries around the world implemented strict protocols ordering schools to close. As a result, educational institutions were forced to establish a new form of schooling by implementing emergency remote education. Learning from home during the Covid-19 pandemic brought numerous changes, challenges, and stressors to students' daily lives. In this context, major concerns have been raised based on the reports of students' negative experiences resulting from social distancing and isolation. Given the impact of Covid-19 on many aspects of students' lives, in particular their social and school experiences, research that provides insights into the consequences of this health crisis for students' well-being has become important. This study aims to explore students' experiences of social distancing and its relation to their negative emotional experiences during Germany's first Covid-19-related school closure. Findings indicate that both primary and secondary students missed their friends and classmates and that primary school students perceived higher levels of social distancing. However, a linear regression analysis indicated that the older the students were, the more negatively affected they were by social distancing. The implications of the study's results and further lines of research are discussed.

Comparing the Time-Dependent Evolution of Microcirculation in Gracilis vs. ALT Flaps Using Laser-Doppler Flowmetry and Tissue-Spectrometry.

Postoperative free flap monitoring is considered a key component of care after microsurgical reconstruction. To achieve successful flap salvage after surgical revision, early recognition of vascular compromise is required. The aim of this study was to assess and compare the time-dependent evolution of microcirculation in gracilis muscle (GM) and anterolateral thigh (ALT) flaps. This study included continuous measurements of blood flow (flow), hemoglobin oxygenation (SO2) and the relative amount of hemoglobin (rHb) using laser-doppler flowmetry and tissue-spectrometry (O2C, LEA Medizintechnik, Gießen, Germany) over a time-period of 72 h. Microcirculation was assessed in a total of 66 viable free flaps (GM n = 40; ALT n = 26). A statistically significant positive correlation between time post-anastomosis and microvascular flow was found for both GM and ALT flaps with rs = 0.384 (p < 0.001) and rs = 0.178 (p = 0.015), respectively. No significant positive or negative correlations between time post-anastomosis and SO2 were found for both GM and ALT flaps with rs = 0.052 (p = 0.387) and rs = −0.018 (p = 0.805), respectively. Overall, a significant negative correlation between time post-anastomosis and rHb was found for GM flaps with rs = −0.140 (p = 0.019). For ALT flaps, no significant positive or negative correlation was found with rs = −0.011 (p = 0.887). Microcirculation differs in different flap entities, and surgeons should be aware of these differences in order to correctly evaluate and classify the values of flow, SO2 and rHb obtained when using the O2C device for postoperative monitoring.

STAT1 regulates macrophage number and phenotype and prevents renal fibrosis after ischemia-reperfusion injury.

Renal ischemia-reperfusion injury (IRI) leads to acute kidney injury or delayed allograft function, which predisposes to fibrosis in the native kidney or kidney transplant. Here we investigated the role of the signal transducer and activator of transcription 1 (STAT1) in inflammatory responses following renal IRI. Our study showed that a subsequent stimulation of Janus-activated kinase 2/STAT1 and Toll-like receptor 4 pathways led to greater STAT1 activation followed by increased cytokine transcription compared with single-pathway stimulation in murine renal tubular cells. Moreover, we observed increased activation of STAT1 under hypoxic conditions. In vivo, STAT1-/- mice displayed less acute tubular necrosis and decreased macrophage infiltration 24 h after renal ischemia. However, investigation of the healing phase (30 days after IRI) revealed significantly more fibrosis in STAT1-/- than in wild-type kidneys. In addition, we demonstrated increased macrophage infiltration in STAT1-/- kidneys. Flow cytometry analysis revealed that STAT1 deficiency drives an alternatively activated macrophage phenotype, which is associated with downregulated cluster of differentiation 80 expression, decreased intracellular reactive oxygen species production, and enhanced ability for phagocytosis. Furthermore, we detected immunohistochemically enhanced STAT1 expression in human renal allograft biopsies with no interstitial fibrosis/tubular atrophy (IF/TA) compared with specimens with severe IF/TA without specific etiology. Thus, STAT1 activation drives macrophages toward an alternatively activated phenotype and enhances fibrogenesis indicating a potential STAT1-driven protective mechanism in tissue repair after ischemic injury.