The response to stressors in adulthood depends on the interaction between prenatal exposure to glucocorticoids and environmental context.

Maternal stress during reproduction can influence how offspring respond to stress later in life. Greater lifetime exposure to glucocorticoid hormones released during stress is linked to greater risks of behavioral disorders, disease susceptibility, and mortality. The immense variation in individual's stress responses is explained, in part, by prenatal glucocorticoid exposure. To explore the long-term effects of embryonic glucocorticoid exposure, we injected Japanese quail (Coturnix japonica) eggs with corticosterone. We characterized the endocrine stress response in offspring and measured experienced aggression at three different ages. We found that prenatal glucocorticoid exposure affected (1) the speed at which the stress response was terminated suggesting dysregulated negative feedback, (2) baseline corticosterone levels in a manner dependent on current environmental conditions with higher levels of experienced aggression associated with higher levels of baseline corticosterone, (3) the magnitude of an acute stress response based on baseline concentrations. We finish by proposing a framework that can be used to test these findings in future work. Overall, our findings suggest that the potential adaptive nature of prenatal glucocorticoid exposure is likely dependent on environmental context and may also be tempered by the negative effects of longer exposure to glucocorticoids each time an animal faces a stressor.

Intraoperative Greater Trochanteric Fractures During Revision Total Hip Arthroplasty May Not Always Need Surgical Fixation.

Many fixation techniques have been described to manage intraoperative greater trochanteric (GT) fractures during revision total hip arthroplasty (rTHA), but complications such as broken hardware and bursitis are common. The purpose of this study was to determine whether surgical fixation of an intraoperative GT fracture resulted in improved outcomes in rTHA. We reviewed a consecutive series of 1442 rTHA patients at our institution from 2008 to 2019. We identified all patients with an intraoperative GT fracture and noted whether the fracture was fixed surgically or left without fixation. Demographics, comorbidities, complications, radiographic union, and dislocations were compared between the groups. Of the 44 (3%) intra-operative GT fractures identified, 23 (52%) underwent fixation, most commonly with claw plates (8 patients) and cables (10 patients). There were no differences in the rates of radiographic union (86% vs 100%, P=.100), dislocations (4% vs 10%, P=.599), or re-revision (10% vs 13%, P=1.000) between the groups. Patients undergoing fixation had a higher rate of bursitis postoperatively, but it was not significant with the numbers available (35% vs 10%, P=.072). Our cohort of GT fractures at a large revision referral institution represents the largest reported series of GT fractures during rTHA. Surgical fixation in rTHA did not show improved outcomes in terms of dislocation, re-revision, and radiographic union compared with those fractures that were not fixed. There was a trend toward increased postoperative bursitis in the group undergoing surgical fixation. Further research is needed on this topic, as the number of rTHAs continues to increase. [Orthopedics. 2023;46(5):297-302.].

A retrievable, dual-chamber stent protects against warm ischemia of donor organs in a model of donation after circulatory death.

BACKGROUND: Ischemic injury during the agonal period of donation after circulatory death donors remains a significant barrier to increasing abdominal transplants. A major obstacle has been the inability to improve visceral perfusion, while at the same time respecting the ethics of the organ donor. A retrievable dual-chamber stentgraft could potentially isolate the organ perfusion from systemic hypotension and hypoxia, without increasing cardiac work or committing the donor. METHODS: Retrievable dumbbell-shaped stents were laser welded from nitinol wire and covered with polytetrafluoroethylene. Yorkshire pigs were assigned to either agonal control or dumbbell-shaped dual-chamber stentgraft. A central lumen maintained aortic flow, while an outer visceral chamber was perfused with oxygenated blood. A 1-hour agonal phase of hypoxia and hypotension was simulated. Stents were removed by simple sheath advancement. Cardiac monitoring, labs, and visceral flow were recorded followed by recovery of the animal to a goal of 48 hours. RESULTS: Cardiac stress did not increase during stent deployment. Visceral pO2 and flow were dramatically improved in stented animal relative to control animals. Five of 7 control animals were killed after renal failure complications, whereas all stent animals survived. Histology confirmed increased ischemic changes among control kidneys compared to stented animals. CONCLUSION: A dual-chamber stent improved outcomes after a simulated agonal phase. The stent did not increase cardiac work, thus respecting a key ethical consideration. The ability of a dual-chamber stent to prevent ischemia during organ recovery may become a powerful tool to address the critical donor organ shortage.

Is there an oxidative cost of acute stress? Characterization, implication of glucocorticoids and modulation by prior stress experience.

Acute rises in glucocorticoid hormones allow individuals to adaptively respond to environmental challenges but may also have negative consequences, including oxidative stress. While the effects of chronic glucocorticoid exposure on oxidative stress have been well characterized, those of acute stress or glucocorticoid exposure have mostly been overlooked. We examined the relationship between acute stress exposure, glucocorticoids and oxidative stress in Japanese quail (Coturnix japonica). We (i) characterized the pattern of oxidative stress during an acute stressor in two phenotypically distinct breeds; (ii) determined whether corticosterone ingestion, in the absence of acute stress, increased oxidative stress, which we call glucocorticoid-induced oxidative stress (GiOS); and (iii) explored how prior experience to stressful events affected GiOS. Both breeds exhibited an increase in oxidative stress in response to an acute stressor. Importantly, in the absence of acute stress, ingesting corticosterone caused an acute rise in plasma corticosterone and oxidative stress. Lastly, birds exposed to no previous acute stress or numerous stressful events had high levels of GiOS in response to acute stress, while birds with moderate prior exposure did not. Together, these findings suggest that an acute stress response results in GiOS, but prior experience to stressors may modulate that oxidative cost.