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Obesity is associated with numerous changes in skeletal muscle including greater muscle mass and muscle fiber cross sectional area (FCSA), yet fasted muscle protein synthesis is lower. Activation of the IGF-1/Akt/mTOR pathway is critical for muscle mass maintenance, muscle hypertrophy, and muscle protein regulation. Resistance exercise (RE) increases muscle mass, FCSA, and IGF-1. Persons with obesity have greater skeletal muscle mass and larger skeletal muscle fiber cross sectional area. The IGF-1/Akt/mTOR pathway is critical for the regulation of skeletal muscle mass. Our study found men and women with obesity have lower skeletal muscle IGF-1 mRNA and protein and higher expression of miR-206 an epigenetic regulator of IGF-1, at rest and following an acute bout of resistance exercise. Despite this, Akt mediated signaling was maintained and maintenance of phosphorylation does not appear to be accounted for by compensatory pathways. Our findings suggest a possible negative feedback mechanism via increased miR-206 and in turn decreased IGF-1 to limit further skeletal muscle hypertrophy in persons with obesity. The current work investigated if: (1) obesity dysregulates basal skeletal muscle IGF-1 pathways; and (2) obesity augments the muscle IGF-1 pathway responses to acute RE. Eight sedentary (no self-reported physical activity), lean (LN) and eight sedentary subjects with obesity (OB) had vastus lateralis biopsies taken at rest, and 15 min and 3 h post-acute RE for the measurement of the IGF-1 pathway and muscle FCSA. Type II FCSA was larger in OB vs. LN. Skeletal muscle IGF-1 mRNA and IGF-1 protein were lower in OB vs. LN at rest and post-exercise. Acute RE increased IGF-1 protein similarly in both groups. The expression of miR-206, a post-transcriptional inhibitor of IGF-1 expression, was higher in OB vs. LN and linked with lower IGF-1 mRNA (r = – 0.54). In spite of greater muscle FCSA, muscle IGF-1 expression was lower in obesity suggesting negative feedback may be limiting muscle mass expansion in obesity.

OBJECTIVE: Burnout is prevalent among vascular surgery trainees. Here we aim to identify modifiable risk factors for burnout in vascular surgery training, to facilitate the development of programs to enhance and sustain trainee well-being. METHODS: The Association of Program Directors in Vascular Surgery issued the Annual Training survey in the fall of 2018 to all trainees. The survey contained items to assess frequency of burnout, as well as mentorship, training environment, and stress coping mechanisms using an abbreviated COPE (Coping Orientation to Problems Experienced) inventory. RESULTS: Of 628 surveys issued, the response rate was 30% (n = 188). Respondents indicated that the majority of programs offer mentorship opportunities (n = 150 [83%]) that are longitudinal throughout the duration of training (n = 140 [77%]). Fifty-eight percent (n = 109) indicated there was an appropriate balance between learning and productivity in their program, with more respondents leaning toward too much clinical productivity (n = 57) and fewer toward too much learning (n = 19). Forty-five percent of respondents indicated feeling burnout at least weekly (n = 81). The burnout group was less likely to report an appropriate balance between clinical productivity and learning (49.4% vs 67.7%; P < .001), as well as a lower frequency of mentorship opportunities (72.1% vs 92.7%; P < .001). Certain coping skills were used more frequently in the burnout group, including self-distraction, disengagement, humor, self-blame, and substance use. In multivariate analysis, frequent use of self-blame conferred a 9.847-fold increased risk (95% confidence interval, 2.114–45.871) of burnout (P = .003), while feeling appropriately challenged by the faculty was significantly protective (odds ratio for burnout, 0.158; 95% confidence interval, 0.031–0.820; P = .03). CONCLUSIONS: The protective effect against vascular surgery trainee burnout conferred by the availability of mentorship suggests that an expansion and emphasis on mentorship in training may help to mitigate trainee burnout. Mentorship may also be a suitable channel to assess for an appropriate level of challenge, as well as for an appropriate balance between clinical productivity and learning that, when present, are also protective against burnout. Furthermore, the correlation between the frequent use of certain coping skills and burnout highlight this as an area for intervention, potentially through a combination of mentor modeling and formal training on healthy stress-related coping strategies.

AIM: Interventions that decrease atrophy during disuse are desperately needed to maintain muscle mass. We recently found that massage as a mechanotherapy can improve muscle regrowth following disuse atrophy. Therefore, we aimed to determine if massage has similar anabolic effects when applied during normal weight bearing conditions (WB) or during atrophy induced by hindlimb suspension (HS) in adult rats. METHODS: Adult (10 month) male Fischer344-Brown Norway rats underwent either hindlimb suspension (HS, n=8) or normal weight bearing (WB, n=8) for 7 days. Massage was applied using cyclic compressive loading (CCL) in WB (WBM, n=9) or HS rats (HSM, n=9) and included four 30-minute bouts of CCL applied to gastrocnemius muscle every other day. RESULTS: Massage had no effect on any anabolic parameter measured under WB conditions (WBM). In contrast, massage during HS (HSM) stimulated protein turnover, but did not mitigate muscle atrophy. Atrophy from HS was caused by both lowered protein synthesis and higher degradation. HS and HSM had lowered total RNA compared with WB and this was the result of significantly higher ribosome degradation in HS that was attenuated in HSM, without differences in ribosomal biogenesis. Also, massage increased protein turnover in the non-massaged contralateral limb during HS. Finally, we determined that total RNA degradation primarily dictates loss of muscle ribosomal content during disuse atrophy. CONCLUSION: We conclude that massage is an effective mechanotherapy to impact protein turnover during muscle disuse in both the massaged and non-massaged contralateral muscle, but it does not attenuate the loss of muscle mass.

Congenital abdominal wall defects are common anomalies which include gastroschisis, omphalocele and umbilical cord hernia. Recent reports indicate that gastroschisis is increasing in prevalence, whereas omphalocele has remained steady, suggesting that environmental factors may play a part in their pathogenesis. The aim of this study is to review animal teratogen studies resulting in abdominal wall defects to investigate their possible causes. Each report was examined not only for the teratogens causing the defects, but also to carefully identify the defect occurring and its correlation with the known clinical anomalies. We found many discrepancies between the nomenclature used by animal teratology investigators and that used by clinicians. We were able to confirm the induction of gastroschisis by 22 teratogens, omphalocele by 9 teratogens and umbilical cord hernia by 8. There is no doubt that environmental factors may be responsible, at least in part, for all three of the clinical abdominal wall defects. Future studies should take care to appreciate the differences between these anomalies and describe them in detail, so that accurate and meaningful conclusions can be obtained.

Background The literature directly comparing the utility of clinical examination (CE) to that of CT in detecting recurrence of squamous cell carcinoma (SCC) for primary site recurrences is lacking. Methods Patients who received both CT scans and CEs after primary treatment for SCC of the upper aerodigestive tract (oropharynx, hypopharynx, and larynx) were identified. Individual CT scans and CEs were evaluated for their ability to detect recurrence status. Results One hundred thirty-one patients underwent a total of 886 CEs and 346 CT scans during the follow-up period. The sensitivity for CE and CT was 84.0% and 66.7%, respectively; for specificity, 98.7% and 90.7%, respectively; for positive predictive value, 65.6% and 31.8%, respectively; and for negative predictive value the values were 99.5% and 97.7%, respectively. Conclusion Due to the low sensitivity and positive predictive value of CT scans compared to physical examination in evaluating primary site tumor recurrences, the utility of CT for surveillance may be limited. © 2010 Wiley Periodicals, Inc. Head Neck, 2011

Object The vertebral artery (VA) and its branches may be encountered during various neurosurgical procedures such as far lateral suboccipital approaches to the skull base and spinal operations. Therefore, a working knowledge of the distribution and significance of such VA branches may be advantageous to the surgeon. To date, quantitation of these branches is lacking in the literature. Methods The authors evaluated the branches of 20 VAs from 10 adult cadavers and assessed the distribution and surgical significance of the branches from the V2 and V3 segments. Results In terms of target tissues, the VA branches encountered at the C1–2 level were most likely to be muscular, branches at C2–3 osseous, and those at C3–6 radicular. No radicular or medullary branches were identified arising from any V3 segment of the VA or C1–2 level of the V2 segment. The greatest concentration of branches per level was found arising from the V2 segment at C2–3. Posterior branches of the VA tended to be radicular or muscular, whereas anterior branches tended to be radicular or osseous. Lateral branches were most commonly radicular and medial branches tended to be osseous or muscular in nature. The largest branches of the VA originated from its V3 segment or the C2–3 part of its V2 segment. Rarely, branches to the extracranial glossopharyngeal and spinal accessory nerves were identified originating from the V3 and V2 segments of the VA, respectively. Conclusions Although seemingly diverse in their distribution, the branches of the V2 and V3 segments of the VA may follow a certain consistent arrangement. The potential for injury to neural branches of the VA is minimal at its V3 segment and the C1–2 portion of its V2 segment. Such knowledge may be of use to the neurosurgeon who operates in the neck and at the craniocervical junction.

Purpose Raman spectroscopy has distinguished malignant from normal tissues in several types of cancer. This is the first report of applying Raman spectroscopy to the diagnosis of Wilms' tumor. Methods Specimens of normal kidney, Wilms' tumor, xanthogranuloma, nephrogenic rests, and rhabdoid tumor were collected fresh from the operating room. Specimens of Wilms' tumor, normal kidney, and congenital mesoblastic nephroma were retrieved from the cryobank and thawed to room temperature. At least 12 Raman spectra were collected from each tissue sample. Histologic slides of each specimen were reviewed by pediatric pathologists. A computer algorithm based on discriminant function analysis (DFA) classified the Raman spectra of Wilms' tumor and the normal sample. Results Four hundred sixty-seven spectra were collected from 41 specimens. Using DFA, Raman spectroscopy differentiated Wilms' tumor from normal with 100% sensitivity and specificity and treated from untreated Wilms' tumor with 100% sensitivity and specificity. Using a DFA model built from cryopreserved specimens but applied to fresh Wilms' and normal samples, the sensitivity and specificity were 93.3% and 90.9%, respectively. Conclusion Raman spectroscopy is an accurate technique for differentiating Wilms' tumor from normal kidney and treated from untreated Wilms' tumor. It has potential to diagnose in minutes what currently takes several hours to days.