Adulte interfollicular epidermis (IFE) renewal is likely orchestrated by physiological demands of its complex tissue architecture comprising spatial and cellular heterogeneity. Mouse tail and back skin display two kinds of basal IFE spatial domains that regenerate at different rates. Here, we elucidate the molecular and cellular states of basal IFE domains by marker expression and single-cell transcriptomics in mouse and human skin. We uncover two paths of basal cell differentiation that in part reflect the IFE spatial domain organization. We unravel previously unrecognized similarities between mouse tail IFE basal domains defined as scales and interscales versus human rete ridges and inter-ridges, respectively. Furthermore, our basal IFE transcriptomics and gene targeting in mice provide evidence supporting a physiological role of IFE domains in adaptation to differential UV exposure. We identify Sox6 as a novel UV-induced and interscale/inter-ridge preferred basal IFE-domain transcription factor, important for IFE proliferation and survival. The spatial, cellular, and molecular organization of IFE basal domains underscores skin adaptation to environmental exposure and its unusual robustness in adult homeostasis.

Study Design Retrospective Cohort Study Objective Cervical radiculopathy meeting operative criteria has traditionally been managed using anterior cervical discectomy and fusion (ACDF). However, cervical disc arthroplasty (CDA) and posterior cervical foraminotomy (PCF) are also reasonable options. This study aimed to assess differences in postoperative outcomes among patients undergoing multi-level ACDF, CDA, or PCF comparing medical/surgical complications and healthcare utilization parameters. Methods Patients who underwent multi-level ACDF, CDA, or PCF between 2012 and 2019 were identified from the American College of Surgeons National Surgical Quality Improvement Project (ACS-NSQIP) database. Patients were stratified based on procedure type and propensity score matched to resolve baseline differences. ANOVA was performed to identify differences in medical complications, surgical complications, and healthcare utilization metrics. Results A total of 31 344 patients who underwent an eligible procedure were identified (ACDF: n = 28 089, CDA: n = 1748, PCF: n = 1507), and 684 patients remained in each group following propensity score matching. Patients undergoing multi-level PCF were found to experience longer lengths of hospital stay (PCF: 1.67 ± 1.61 days, ACDF: 1.50 ± 1.32 days, CDA: 1.27 ± 1.05 days, P < .001), higher rates of reoperation (PCF: 3.2%, ACDF: 1.0%, CDA: .4%, P = .020), superficial infection (PCF: 1.3%, ACDF: .3%, CDA: .1%, P = .008) and deep infection (PCF: 1.2%, ACDF: 0%, CDA: 0%, P < .001). There were no outcome differences between multi-level ACDF and CDA. Conclusions Patients undergoing multi-level PCF were at increased risk for longer hospital stay, re-operation, and infection relative to those undergoing ACDF and CDA. Future research should aim to uncover the precise mechanisms underlying these complications, as well as analyze long term outcomes. Level of Evidence III

Adult interfollicular epidermis (IFE) renewal is likely orchestrated by physiological demands of its complex tissue architecture comprising spatial and cellular heterogeneity. Mouse tail and back skin display two kinds of basal IFE spatial domains that regenerate at different rates. Here we elucidate the molecular and cellular states of basal IFE domains by marker expression and single cell transcriptomics in mouse and human skin. We uncover two paths of basal cell differentiation that reflect in part the IFE spatial domain organization. We unravel previously unrecognized similarities between mouse tail IFE basal domains defined as scales and interscales versus human rete ridges and inter-ridges, respectively. Second, our basal IFE transcriptomics and gene targeting in mice provide evidence supporting a physiological role of IFE domains: adaptation to differential UV exposure. We identify Sox6 as a novel UV-induced and interscale/inter-ridge basal IFE-domain transcription factor, important for IFE proliferation and survival. The spatial, cellular, and molecular organization of IFE basal domains underscores skin adaptation to environmental exposure and its unusual robustness in adult homeostasis.

Although intramedullary nailing (IMN) is considered the standard of care for the surgical management of most femur metastatic diseases, the optimal treatment of metastatic humeral impending and/or pathologic fractures is still debatable. Moreover, the use of cemented humeral nails has not been thoroughly studied, and only a few small series have compared their results with uncemented nails. The purpose of this study was to compare the (1) survivorship, (2) functional outcomes, and (3) perioperative complications in patients receiving cemented versus uncemented humerus IMN for impending or complete pathologic fractures resulting from metastatic disease or multiple myeloma. We retrospectively reviewed 100 IMNs in 82 patients, of which 53 were cemented and 47 were uncemented. With a mean survival of 10 months (Cemented: 8.3 months vs. Uncemented: 11.6 months, p = 0.34), the mean Musculoskeletal Tumor Society (MSTS) scores increased from 42.4% preoperatively (Cemented: 40.2% vs. Uncemented: 66.7%, p = 0.01) to 89.2% at 3 months postoperatively (Cemented: 89.8% vs. Uncemented: 90.9%, p = 0.72) for the overall group (p < 0.001). Both cohorts yielded comparable complication rates (overall [22.6% vs. 19.1%)], surgical ([11.3% vs. 4.3%], and medical [13.2% vs. 14.9%], all p > 0.05), but estimated blood loss was significantly higher in the cemented group (203 mL vs. 126 mL, p = 0.003). Thus, intramedullary nailing, with and without cement augmentation in select patients, is a relatively safe and effective therapeutic modality for metastatic humeral disease with similar clinical outcomes and acceptable complication rates. While controlling for possible selection bias, larger-scale, higher-level studies are warranted to validate our results.