The obstetric experience among vascular surgery trainees

BACKGROUND: Vascular surgery training poses unique risks to pregnancy, including long hours, physically demanding work, and radiation exposure. Our objectives were to (1) understand pregnancy and parenthood experiences among vascular surgery trainees, (2) assess the rate of obstetric complications among vascular trainees, and (3) evaluate factors associated with trainee-parent wellness. METHODS: A survey was administered after the 2021 Vascular Surgery In-Training Examination. Residents and fellows who (or whose partners) experienced pregnancies during their clinical years of training were asked about their perceptions of the learning environment (work hours and mistreatment, including discrimination, bullying, and harassment), obstetric complications (miscarriage, pre-eclampsia, placental abruption, intrauterine growth restriction, cesarean section, and postpartum depression), and burnout. Multivariable logistic regression models identified factors associated with burnout. RESULTS: Among 510 trainees from 123 vascular surgery training programs (response rate 85.9%), 128 (25.1%) reported pregnancy during clinical training (12.7% female and 35.4% male; P \u3c .001). Compared with male trainees, female trainees more frequently reported delaying having children owing to training (53.1% vs 30.0%; P \u3c .001) and being advised against having children during residency (7.9% vs 0.4%; P \u3c .001). Both female trainees and the partners of male trainees had high rates of obstetric complications (female 47.1% vs partners of male trainees 34.0%; P = .3). Compared with male trainees who had female partners, female trainees more frequently reported pregnancy/parenthood-related mistreatment (female 60.0% vs male 15.6%; P = .002) and duty-hour violations (female 47.4% vs male 12.0%; P \u3c .001). Female gender was associated with increased risk for burnout (odds ratio, 4.8; 95% confidence interval,1.14-20.15); however, this difference was no longer significant after adjusting for mistreatment and duty-hour violations. CONCLUSIONS: Vascular trainees experience high rates of obstetric complications. Senior-level trainees were more likely to experience obstetric complications, potentially owing to older age, longer and more complex surgical cases, and increased frequency of overnight calls. Women experienced more stigma related to pregnancy and childbearing, which may be associated with higher rates of burnout. Increased support for childbearing during training may help to maintain the wellness of a diverse workforce and better maternal-fetal health

Brainstem Respiratory Oscillators Develop Independently of Neuronal Migration Defects in the Wnt/PCP Mouse Mutant looptail

The proper development and maturation of neuronal circuits require precise migration of component neurons from their birthplace (germinal zone) to their final positions. Little is known about the effects of aberrant neuronal position on the functioning of organized neuronal groups, especially in mammals. Here, we investigated the formation and properties of brainstem respiratory neurons in looptail (Lp) mutant mice in which facial motor neurons closely apposed to some respiratory neurons fail to migrate due to loss of function of the Wnt/Planar Cell Polarity (PCP) protein Vangl2. Using calcium imaging and immunostaining on embryonic hindbrain preparations, we found that respiratory neurons constituting the embryonic parafacial oscillator (e-pF) settled at the ventral surface of the medulla in Vangl2Lp/+ and Vangl2Lp/Lp embryos despite the failure of tangential migration of its normally adjacent facial motor nucleus. Anatomically, the e-pF neurons were displaced medially in Lp/+ embryos and rostro-medially Lp/Lp embryos. Pharmacological treatments showed that the e-pF oscillator exhibited characteristic network properties in both Lp/+ and Lp/Lp embryos. Furthermore, using hindbrain slices, we found that the other respiratory oscillator, the preBötzinger complex, was also anatomically and functionally established in Lp mutants. Importantly, the displaced e-pF oscillator established functional connections with the preBötC oscillator in Lp/+ mutants. Our data highlight the robustness of the developmental processes that assemble the neuronal networks mediating an essential physiological function

Endothelium-dependent effects of carteolol

Experiments were designed to study the effect of the beta adrenergic antagonist, carteolol, on the endothelium-dependent responsiveness of isolated arteries. Rings of canine coronary arteries were suspended in organ chambers for isometric tension recording; carteolol inhibited the relaxation to isoproterenol and abolished the difference in responsiveness to the beta adrenergic agonist between rings with and without endothelium. Carteolol did not cause endothelium-dependent relaxations of femoral or coronary arteries. In bioassay experiments, carteolol augmented the basal release of relaxing factors from the endothelium of the femoral artery; this effect was prevented by indomethacin. In rings of femoral arteries, carteolol increased the endothelium-dependent relaxations induced by the alpha-2 adrenergic agonist UK 14,304; this was not affected by indomethacin but prevented by propranolol. Carteolol did not modify the endothelium-dependent relaxations to acetylcholine, adenosine diphosphate, bradykinin, thrombin and the Ca+-ionophore A23187. Carteolol inhibited the endothelium-dependent hypoxic contraction of the canine coronary artery. It did not affect endothelium-dependent contractions to acetylcholine in the aorta of the spontaneously hypertensive rat. These experiments suggest that carteolol facilitates the abluminal release of endothelium-dependent relaxing factor caused by alpha-2 adrenergic activation, and causes the intraluminal release of vasodilator prostaglandins. The compound prevents the endothelium-dependent contractions which are not mediated by products of cyclooxygenase. These actions may contribute to the vasodilator properties of carteolol in the intact organism.link_to_subscribed_fulltex

Episodic hypoxia evokes long-term facilitation of genioglossus muscle activity in neonatal rats

The aim of this study was to determine if episodic hypoxia evokes persistent increases of genioglossus muscle (GG) activity, termed long-term facilitation (LTF), in neonatal rats in vivo. Experiments were performed on anaesthetized, spontaneously breathing, intubated neonatal rats (postnatal days (P) 3–7), divided into three groups. The first group (n = 8) was subjected to three 5-min periods of hypoxia (5% O(2)–95% N(2)) alternating with 5 min periods of room air. The second group (n = 8) was exposed to 15 min of continuous hypoxia. The third (n = 4) group was not exposed to hypoxia and served as a control. GG EMG activity and airflow were recorded before, during and for 60 min after episodic and continuous hypoxic exposure. During hypoxia, GG EMG burst amplitude and tidal volume (V(T)) significantly increased compared to baseline levels (episodic protocol: mean ±s.e.m.; 324 ± 59% of control and 0.13 ± 0.007 versus 0.09 ± 0.005 ml, respectively; continuous protocol: 259 ± 30% of control and 0.16 ± 0.005 versus 0.09 ± 0.007 ml, respectively; P < 0.05). After the episodic protocol, GG EMG burst amplitude transiently returned to baseline; over the next 60 min, burst amplitude progressively increased to levels significantly greater than baseline (238 ± 40% at 60 min; P < 0.05), without any significant increase in V(T) and respiratory frequency (P> 0.05). After the continuous protocol, there was no lasting increase in GG EMG burst amplitude. We conclude that LTF of upper airway muscles is an adaptive respiratory behaviour present from birth

Evaluation and application of the CPM Dairy Nutrition model

The Cornell-Penn-Miner (CPM) Dairy is an applied mathematical nutrition model that computes dairy cattle requirements and the supply of energy and nutrients based on characteristics of the animal, the environment and the physicochemical composition of the feeds under diverse production scenarios. The CPM Dairy was designed as a steady-state model to use rates of degradation of feed carbohydrate and protein and the rate of passage to estimate the extent of ruminal fermentation, microbial growth, and intestinal digestibility of carbohydrate and protein fractions in computing energy and protein post-rumen absorption, and the supply of metabolizable energy and protein to the animal. The CPM Dairy version 3.0 (CPM Dairy 3.0) includes an expanded carbohydrate fractionation scheme to facilitate the characterization of individual feeds and a sub-model to predict ruminal metabolism and intestinal absorption of long chain fatty acids. The CPM Dairy includes a non-linear optimization algorithm that allows for least-cost formulation of diets while meeting animal performance, feed availability and environmental restrictions of modern dairy cattle production. When the CPM Dairy 3.0 was evaluated with data of 228 individual lactating dairy cows containing appropriate information including observed dry matter intake, the linear regression between observed and model-predicted milk production values indicated the model was able to account for 79.8% of the variation. The concordance correlation coefficient (CCC) was high (rc=0.89) without a significant mean bias (0.52 kg/d; P=0.12). The accuracy estimated by the CCC was 0.997. The root of mean square error of prediction (MSEP) was 5.14 kg/d (0.16 of the observed mean) and 87.3% of the MSEP was due to random errors, suggesting little systematic bias in predicting milk production of high-producing dairy cattle. Based upon these evaluations, it was concluded the CPM Dairy 3.0 model adequately predicts milk production at the farm level when appropriate animal characterization, feed composition and feed intake are provided; however, further improvements are needed to account for individual animal variation