Radial glia-like cells (RGCs) are the hypothesized source of adult hippocampal neurogenesis. However, the current model of hippocampal neurogenesis does not fully incorporate the in vivo heterogeneity of RGCs. In order to better understand the contribution of different RGC subtypes to adult hippocampal neurogenesis, we employed widely-used transgenic lines (Nestin-CreERT2 and GLAST∷CreERT2 mice) to explore how RGCs contribute to neurogenesis under basal conditions and after stimulation and depletion of neural progenitor cells. We first used these inducible fate-tracking transgenic lines to define the similarities and differences in the contribution of nestin- and GLAST-lineage cells to basal long-term hippocampal neurogenesis. We then explored the ability of nestin- and GLAST-lineage RGCs to contribute to neurogenesis, after experimental manipulations that either ablate neurogenesis (i.c.v. application of the anti-mitotic AraC, cytosine-β-D-arabinofuranoside) or stimulate neurogenesis (wheel running). Interestingly, in both ablation and stimulation experiments, labeled RGCs in GLAST∷CreERT2 mice appear to contribute to neurogenesis, whereas RGCs in Nestin-CreERT2 mice do not. Finally, using NestinGFP reporter mice, we expanded on previous research by showing that not all RGCs in the adult dentate gyrus subgranular zone express nestin, and therefore RGCs are antigenically heterogeneous. These findings are important for the field, as they allow appropriately conservative interpretation of existing and future data that emerge from these inducible transgenic lines. These findings also raise important questions about the differences between transgenic driver lines, the heterogeneity of RGCs, and the potential differences in progenitor cell behavior between transgenic lines. As these findings highlight the possible differences in the contribution of nestin and GLAST lineage cells to long-term neurogenesis in vivo, they indicate that the current models of hippocampal neurogenesis should be modified to include RGC lineage heterogeneity.

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OBJECTIVEThis study aims to assess the relationship of comorbidities and postoperative complications to rates of readmission for geriatric patients undergoing anterior cervical discectomy and fusion (ACDF) involving more than 2 levels on an inpatient or outpatient basis. With the rising costs of healthcare in the United States, understanding the safety and efficacy of performing common surgical interventions (including ACDF) as outpatient procedures could prove to be of great economic impact.Objective This study aims to assess the effect of comorbidities and postoperative complications on the rates of readmission of geriatric patients undergoing multilevel anterior cervical discectomy and fusion (ACDF) procedures (i.e., ACDF involving 3 or more levels) on an inpatient or outpatient basis. Same-day surgery has been demonstrated to be a safe and cost-effective alternative to the traditional inpatient option for many surgical interventions. With the rising costs of healthcare, understanding the safety and efficacy of performing common surgical interventions as outpatient procedures could prove to be of great economic impact.METHODSThe study population included total of 2492 patients: 2348 inpatients and 144 outpatients having ACDF procedures involving 3 or more levels in the Medicare Standard Analytical Files database. Age, sex, comorbidities, postoperative complications, readmission rates, and surgical procedure charges were compared between both cohorts. For selected variables, logistic regression was used to model odds ratios for various comorbidities against readmission rates for both inpatient and outpatient cohorts. Chi-square tests were also calculated to compare these comorbidities with readmission in each cohort.RESULTSOverall complication rates within 30 postoperative days were greater for inpatients than for outpatients (44.2% vs 12.5%, p < 0.001). More inpatients developed postoperative urinary tract infection (7.9% vs 0%, p < 0.001), and the inpatient cohort had increased risk of readmission with comorbidities of anemia (OR 1.52, p < 0.001), smoking (OR 2.12, p < 0.001), and BMI ≥ 30 (OR 1.43, p < 0.001). Outpatients had increased risk of readmission with comorbidities of anemia (OR 2.78, p = 0.047), diabetes mellitus type 1 or 2 (OR 3.25, p = 0.033), and BMI ≥ 30 (OR 3.95, p = 0.008). Inpatients also had increased readmission risk with a postoperative complication of surgical site infection (OR 2.38, p < 0.001). The average charges for inpatient multilevel ACDF were significantly higher than for multilevel ACDF performed on an outpatient basis ($12,734.27 vs $12,152.18, p = 0.0019).CONCLUSIONSThis study suggests that ACDF surgery involving 3 or more levels performed as an outpatient procedure in the geriatric population may be associated with lower rates of readmissions, complications, and surgical charges.

Purpose: This review was undertaken in order to provide an updated summary of the current literature on outcomes for various surgical treatments for cubital tunnel syndrome.Methods: Studies reporting outcomes for surgical treatment of cubital tunnel syndrome were collected through the PubMed database. Study structure, number of participants/procedures, mean follow-up times, scoring scales, and outcomes were collected according to the type of surgery: open decompression, endoscopic decompression, minimal incision, subcutaneous transposition, intramuscular transposition, and submuscular transposition.Results: Our findings indicate varying but comparable levels of success among all surgical techniques reviewed. Many different scoring scales were utilized, limiting direct quantitative comparison between most studies.Discussion: While some studies directly compared two or more techniques, there was rarely a statistically significant difference between groups. In comparisons that did reach statistically significant differences, there were others yet that found no difference in comparing the same techniques.Conclusions: None of the techniques in this review has demonstrated universal superiority above all others, but all appear to be effective in the treatment of cubital tunnel syndrome. The only consensus seems to be that transposition is preferred where the ulnar nerve tends to subluxate either on preoperative or intraoperative examination.

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