Influence of resident involvement on fluoroscopy time and ionizing radiation exposure in fluoroscopy-guided spinal procedures.

BACKGROUND: Fluoroscopic guidance has become the standard for a variety of medical procedures. Mastering these techniques requires practice, which may entail additional radiation for patients and providers. Despite their widespread use, the literature examining factors influencing radiation exposure in fluoroscopically guided pain procedures is scarce. OBJECTIVE: To evaluate the influence of resident involvement on radiation exposure during fluoroscopy-guided spinal interventions. DESIGN: Single-center, observational study. SETTING: Outpatient physiatry clinic in a teaching hospital. PATIENTS: All patients who received cervical or lumbar facet block(s) (FBs), transforaminal epidural steroid injection(s) (TFESIs) without digital subtraction, or a caudal epidural (CE) during the study period were included. INTERVENTIONS: Resident involvement in the procedures: absent, observing, or participating. MAIN OUTCOME MEASURES: Machine-indicated fluoroscopy time (seconds) and radiation dose (milligrays [mGy]). RESULTS: Two hundred ninety six procedures were included: 188 FBs (58 cervical, 130 lumbar), 48 CEs, and 60 TFESIs. For lumbar FBs, fluoroscopy time and radiation dose increased significantly when residents performed them (meantime = 24.5 s, confidence interval [CI] = 20.4-28.7; meandose = 3.53 mGy, CI = 2.57-4.49) compared to when they observed (meantime = 9.9 s, CI = 8.1-11.7; meandose = 1.28 mGy, CI = 0.98-1.59) (mean difference: time = 14.63 s, CI = 9.31-19.94; dose = 2.25 mGy, CI = 1.17-3.33) and were absent during the procedure (meantime = 12.9 s, CI = 11.1-14.6; meandose = 1.65 mGy, CI = 1.40-1.89) (mean difference: time = 11.67 s, CI = 7.35-15.98; dose = 1.88 mGy, CI = 1.01-2.76). In the case of TFESIs, time, but not dose, increased significantly when residents observed (meantime = 39.1 s, CI = 30.7-47.6; meandose = 6.73 mGy, CI = 3.39-10.07) compared to when they were absent (meantime = 27.1 s, CI = 22.4-31.8; meandose = 4.41 mGy, CI = 3.06-5.76 (mean difference: time = 11.99 s, CI = 1.37-22.61; dose = 2.32 mGy, CI = -1.20-5.84). Finally, resident involvement did not significantly affect the outcomes for CEs (ptime = .032, pdose = .74) and cervical FBs (ptime = .64, pdose = .68). CONCLUSION: Resident participation affected lumbar FBs the most, with an increase in both fluoroscopy time and radiation dose.

Incidence and Risk Factors of Systemic Adverse Effects and Complications of Ultrasound- and Fluoroscopy-Guided Glucocorticoid Injections: A Retrospective Cohort Study.

OBJECTIVES: The aims of the study are to assess the incidence of systemic adverse effects and complications of ultrasound-guided and fluoroscopy-guided glucocorticoid injections and to identify associated risk factors. DESIGN: This retrospective cohort study compared participants who received a glucocorticoid injection at the outpatient clinic and participants who had an appointment but did not receive a glucocorticoid injection. Participants were called to verify whether they had experienced any of the predetermined systemic adverse effects and complications. Multiple binary logistic regression was used to identify systemic adverse effect and complication risk factors. RESULTS: There were 1010 participants in the glucocorticoid injection group and 328 in the nonglucocorticoid injection group. There was no statistically significant difference in the occurrence of systemic infection and decompensated heart failure between the two groups. More participants in the glucocorticoid injection group developed abnormal uterine bleeding and erectile dysfunction, but the differences did not reach statistical significance. Female participants were 1.9 times more likely to develop systemic adverse effects ( P < 0.001). Younger age ( P < 0.001), diabetes ( P = 0.012), and higher glucocorticoid injection doses ( P = 0.024) were also associated with an increased risk of developing systemic adverse effects. CONCLUSIONS: Identified risk factors for developing glucocorticoid injection systemic adverse effects were younger age, female sex, diabetes, tobacco use, and high glucocorticoid injection doses.

Rats chirp with their mouth full: During an experimental meal, adult male Wistar rats emitted flat ultrasonic vocalisations upon feeding.

Rats produce ultrasonic vocalisation (USVs) that are classified into different types, based on their average frequency. In pups 40 kHz USVs are produced upon social isolation, and in adults USVs can be associated with affective states and specific behavioural patterns (i.e., appetitive 50 kHz vocalisations of frequency range 30-100 kHz, or aversive 20 kHz vocalisations of frequency range 18-30 kHz). Generally, USVs of frequency around 50 kHz are linked to activation of brain reward pathways, during anticipation or experience of rewarding stimuli. Previous studies have described several subtypes of 50 kHz USVs, according to their acoustic properties. We asked whether USV production might be relevant to feeding behaviour. We recorded USVs from 14-week old adult rats during the satisfaction of a physiological need: refeeding following mild food deprivation (17 h overnight fast). We analysed a 10 min consummatory phase, preceded by a 10 min anticipatory phase, as a control for the experimental meal. Following identification of USV subtypes, we applied frequentist and Bayesian (Monte Carlo shuffling) statistical analyses to investigate the relationship between USV emission and rat behaviour. We found that it was not total USV quantity that varied in response to food consumption, but the subtype of USV produced. Most importantly we found that rats who feed tend to produce flat USVs of a frequency around 40 kHz. Beyond the previous reports of circumstantial association feeding-flat USVs, our observation directly correlate vocalisation and ingestive behaviour. Our study highlights that, in addition to quantification of the production rate, study of USV subtypes might inform us further on rat consummatory behaviour. Since this vocalisation behaviour can have a communicative purpose, those findings also illustrate nutrition studies might benefit from considering the possible social dimension of feeding behaviour.

Investigating the relationship between the five-factor model of distress tolerance, anxiety and anxiety sensitivity.

BACKGROUND: Distress tolerance (DT) has been conceptualized as a vulnerability factor for several psychopathologies. A five factor model of DT has been suggested, but its associations with anxiety and anxiety sensitivity have yet to be explored. OBJECTIVES: This study aimed to further validate the five-factor model of DT, identify the associations between its factors and elevated anxiety, and assess if anxiety sensitivity mediates the association between DT and anxiety. DESIGN AND METHODS: This observational study included 330 students and university workers (women = 82.7%; mean age = 27.7 years, SD = 9.4). They completed online questionnaires assessing DT, anxiety sensitivity and anxiety levels. RESULTS: The five-factor model was a good fit to the data (RMSEA = .04). Two factors, and the sex of the participants, contributed to the variance in anxiety (r2 = .418, p < .001). Tolerance of negative emotion was directly (ß = -1.98, 95% CI = [-2.53, -1.42]) and indirectly (ß = -1.10, 95% CI = [-1.55, -.78]) associated with lower anxiety through anxiety sensitivity. Tolerance of uncertainty was also directly (ß = -.08, 95% CI = [-.10, -.06]) and indirectly (ß = -.04, 95% CI = [-.05, -.02]) associated with lower anxiety through anxiety sensitivity. CONCLUSIONS: Tolerance of negative emotion and uncertainty were associated with anxiety independently of the other factors of DT. These associations seem partially explained by the effect of anxiety sensitivity.

Cognitive-Behavioral Therapy for Panic Disorder in Patients with Stable Coronary Artery Disease: A Feasibility Study.

Implementing cognitive-behavioral therapy (CBT), the first-line psychological treatment for panic disorder (PD), may be challenging in patients with comorbid coronary artery disease (CAD).This study aimed at assessing the feasibility and acceptability of a CBT for PD protocol that was adapted to patients suffering from comorbid CAD. It also aimed at evaluating the efficacy of the intervention to reduce PD symptomatology and psychological distress and improve quality of life. This was a single-case experimental design with pre-treatment, post-treatment and 6-month follow-up measures. Patients with PD and stable CAD received 14 to 17 individual, 1-h sessions of an adapted CBT for PD protocol. They completed interviews and questionnaires at pre-treatment, post-treatment and at a 6-month follow-up assessing intervention acceptability, PD symptomatology, psychological distress and quality of life. A total of 6 patients out of 7 completed the intervention and 6-month follow-up, indicating satisfactory feasibility. Acceptability was high (medians of ≥ 8.5 out of 9 and ≥ 80%) both at pre and post treatment. Remission rate was of 83% at post-treatment and 6-month follow-up. The intervention appeared to have positive effects on comorbid anxiety and depression symptoms and quality of life. The intervention appeared feasible and acceptable in patients with comorbid CAD. The effects of the adapted CBT protocol on PD symptoms, psychological distress and quality of life are promising and were maintained at the 6-month follow-up. Further studies should aim at replicating the present results in randomized-controlled trials.

Dopamine Modulates the Processing of Food Odour in the Ventral Striatum.

Food odour is a potent stimulus of food intake. Odour coding in the brain occurs in synergy or competition with other sensory information and internal signals. For eliciting feeding behaviour, food odour coding has to gain signification through enrichment with additional labelling in the brain. Since the ventral striatum, at the crossroads of olfactory and reward pathways, receives a rich dopaminergic innervation, we hypothesized that dopamine plays a role in food odour information processing in the ventral striatum. Using single neurones recordings in anesthetised rats, we show that some ventral striatum neurones respond to food odour. This neuronal network displays a variety of responses (excitation, inhibition, rhythmic activity in phase with respiration). The localization of recorded neurones in a 3-dimensional brain model suggests the spatial segregation of this food-odour responsive population. Using local field potentials recordings, we found that the neural population response to food odour was characterized by an increase of power in the beta-band frequency. This response was modulated by dopamine, as evidenced by its depression following administration of the dopaminergic D1 and D2 antagonists SCH23390 and raclopride. Our results suggest that dopamine improves food odour processing in the ventral striatum.

Targeted Suppression of Lipoprotein Receptor LSR in Astrocytes Leads to Olfactory and Memory Deficits in Mice.

Perturbations of cholesterol metabolism have been linked to neurodegenerative diseases. Glia-neuron crosstalk is essential to achieve a tight regulation of brain cholesterol trafficking. Adequate cholesterol supply from glia via apolipoprotein E-containing lipoproteins ensures neuronal development and function. The lipolysis-stimulated lipoprotein receptor (LSR), plays an important role in brain cholesterol homeostasis. Aged heterozygote Lsr+/- mice show altered brain cholesterol distribution and increased susceptibility to amyloid stress. Since LSR expression is higher in astroglia as compared to neurons, we sought to determine if astroglial LSR deficiency could lead to cognitive defects similar to those of Alzheimer's disease (AD). Cre recombinase was activated in adult Glast-CreERT/lsrfl/fl mice by tamoxifen to induce astroglial Lsr deletion. Behavioral phenotyping of young and old astroglial Lsr KO animals revealed hyperactivity during the nocturnal period, deficits in olfactory function affecting social memory and causing possible apathy, as well as visual memory and short-term working memory problems, and deficits similar to those reported in neurodegenerative diseases, such as AD. Furthermore, GFAP staining revealed astroglial activation in the olfactory bulb. Therefore, astroglial LSR is important for working, spatial, and social memory related to sensory input, and represents a novel pathway for the study of brain aging and neurodegeneration.

Anxiety disorders in patients with noncardiac chest pain: association with health-related quality of life and chest pain severity.

BACKGROUND: Patients with noncardiac chest pain (NCCP) report more severe symptoms and lowered health-related quality of life when they present with comorbid panic disorder (PD). Although generalized anxiety disorder (GAD) is the second most common psychiatric disorder in these patients, its impact on NCCP and health-related quality of life remains understudied. This study describes and prospectively compares patients with NCCP with or without PD or GAD in terms of (1) NCCP severity; and (2) the physical and mental components of health-related quality of life. METHODS: A total of 915 patients with NCCP were consecutively recruited in two emergency departments. The presence of comorbid PD or GAD was assessed at baseline with the Anxiety Disorder Schedule for DSM-IV. NCCP severity at baseline and at the six-month follow-up was assessed with a structured telephone interview, and the patients completed the 12-item Short-Form Health Survey Version 2 (SF-12v2) to assess health-related quality of life at both time points. RESULTS: Average NCCP severity decreased between baseline and the six-month follow-up (p < .001) and was higher in the patients with comorbid PD or GAD (p < .001) at both time points compared to those with NCCP only. However, average NCCP severity did not differ between patients with PD and those with GAD (p = 0.901). The physical component of quality of life improved over time (p = 0.016) and was significantly lower in the subset of patients with PD with or without comorbid GAD compared to the other groups (p < .001). A significant time x group interaction was found for the mental component of quality of life (p = 0.0499). GAD with or without comorbid PD was associated with a lower mental quality of life, and this effect increased at the six-month follow-up. CONCLUSIONS: Comorbid PD or GAD are prospectively associated with increased chest pain severity and lowered health-related quality of life in patients with NCCP. PD appears to be mainly associated with the physical component of quality of life, while GAD has a greater association with the mental component. Knowledge of these differences could help in the management of patients with NCCP and these comorbidities.

Are Patients at Risk for Developing Panic Disorder After an Emergency Department Visit With Noncardiac Chest Pain?

BACKGROUND: Panic disorder (PD) is common in emergency department (ED) patients with noncardiac chest pain (NCCP). The literature suggests that initially PD-free patients may be at increased risk of developing PD in the months or years following an ED visit. OBJECTIVES: This study aims to determine the incidence of PD in the 2 years following an ED visit with NCCP and to identify predictors of incident PD. METHODS: This study was conducted using a longitudinal, observational design. Five hundred eighty-five patients with NCCP (without PD) were recruited in two EDs. They underwent an interview and completed a series of questionnaires assessing anxiety disorders, perceived social support, psychological distress, anxiety sensitivity, comorbidities, and stressful life events. PD was assessed 6 months, 1 year, and 2 years after the initial interview. RESULTS: PD incidence was 11.1% (95% confidence interval: 8.7-13.9) in the two years following the baseline assessment. Anxiety sensitivity (odds ratio = 1.08; 95% confidence interval: 1.04-1.11; P < .001) and stress related to life events (odds ratio = 1.14; 95% confidence interval: 1.06-1.24; P = .001) significantly predicted incident PD. CONCLUSIONS: Patients with NCCP are at high risk for developing PD in the 2 years following an ED visit with NCCP. Anxiety sensitivity and stress related to life events may be promising clinical targets for preventive interventions.

Diet Protein Content and Individual Phenotype Affect Food Intake and Protein Appetence in Rats.

BACKGROUND: A low-protein diet can induce compensatory intake of excess energy. This must be better evaluated to anticipate the obesogenic risk that may result from the dietary recommendations for reducing animal protein consumption. OBJECTIVES: We aimed to further characterize the behavioral and physiological responses to a reduction in dietary protein and to identify the determinants of protein appetite. METHODS: Thirty-two male Wistar rats [4 wk old, (mean ± SEM) 135 ± 32 g body weight] were fed a low-protein (LP; 6% energy value) or normal-protein (NP; 20%) diet for 8 wk. Food intake and body mass were measured during the entire intervention. During self-selection sessions after 4 wk of experimental diets, we evaluated rat food preference between LP, NP, or high-protein (HP; 55%) pellets. At the end of the experiment, we assessed their hedonic response [ultrasonic vocalizations (USVs)] and c-Fos neuronal activation in the olfactory tubercle and nucleus accumbens (NAcc) associated with an LP or HP meal. RESULTS: Rats fed an LP diet had greater food intake (24%), body weight (5%), and visceral adiposity (30%) than NP rats. All LP rats and half of the NP rats showed a nearly exclusive preference for HP pellets during self-selection sessions, whereas the other half of the NP rats showed no preference. This suggests that the appetite for proteins is driven not only by a low protein status but also by individual traits in NP rats. LP or HP meal induced similar USV emission and similar neuronal activation in the NAcc in feed-deprived LP and NP rats, showing no specific response linked to protein appetite. CONCLUSIONS: Protein appetite in rats is driven by low protein status or individual preferences in rats receiving adequate protein amounts. This must be considered and further analyzed, in the context of current recommendations for protein intake reduction.

Epidemiology and prognostic implications of panic disorder and generalized anxiety disorder in patients with coronary artery disease: rationale and design for a longitudinal cohort study.

BACKGROUND: Anxiety is associated with poorer prognosis in patients with coronary artery disease (CAD). Due to their severity and chronic course, anxiety disorders, particularly generalized anxiety disorder (GAD) and panic disorder (PD), are of considerable interest and clinical importance in this population. This study has two main objectives: (1) to estimate the prevalence and incidence of GAD and PD in patients with CAD over a 2-year period and (2) to prospectively assess the association between PD or GAD and adverse cardiac events, treatment adherence, CAD-related health behaviors, quality of life and psychological distress. DESIGN/METHOD: This is a longitudinal cohort study in which 3610 participants will be recruited following a CAD-related revascularization procedure. They will complete an interview and questionnaires at 5 time points over a 2-year period (baseline and follow-ups after 3, 6, 12 and 24 months). The presence of PD or GAD, adherence to recommended treatments, health behaviors, quality of life and psychological distress will be assessed at each time point. Data regarding mortality and adverse cardiac events will be collected with a combination of interviews and review of medical files. DISCUSSION: This study will provide essential information on the prevalence and incidence of anxiety disorders in patients with CAD and on the consequences of these comorbidities. Such data is necessary in order to develop clear clinical recommendations for the management of PD and GAD in patients with CAD. This will help improve the prognosis of patients suffering from both conditions.

Incidence of panic disorder in patients with non-cardiac chest pain and panic attacks.

This study documented the 6-month incidence of panic disorder and its predictors in emergency department patients with panic attacks and non-cardiac chest pain. The assessment included a validated structured interview to identify panic attacks and questionnaires measuring the potential predictors of panic disorder. Presence of panic disorder was assessed 6 months later. The incidence of panic disorder was 10.1 percent (n = 14/138). Anxiety sensitivity was the only significant predictor of the incidence of panic disorder (odds ratio = 1.06; 95% confidence interval = 1.01-1.12). Patients with panic attacks and non-cardiac chest pain are at an elevated risk for panic disorder. This vulnerability appears to increase with anxiety sensitivity.

Physical activity and disability in patients with noncardiac chest pain: a longitudinal cohort study.

BACKGROUND: Noncardiac chest pain (NCCP) is one of the leading reasons for emergency department visits and significantly limits patients' daily functioning. The protective effect of physical activity has been established in a number of pain problems, but its role in the course of NCCP is unknown. This study aimed to document the level of physical activity in patients with NCCP and its association with NCCP-related disability in the 6 months following an emergency department visit. METHODS: In this prospective, longitudinal, cohort study, participants with NCCP were recruited in two emergency departments. They were contacted by telephone for the purpose of conducting a medical and sociodemographic interview, after which a set of questionnaires was sent to them. Participants were contacted again 6 months later for an interview aimed to assess their NCCP-related disability. RESULTS: The final sample consisted of 279 participants (57.0% females), whose mean age was 54.6 (standard deviation = 15.3) years. Overall, the proportion of participants who were physically active in their leisure time, based on the Actimètre questionnaire criteria, was 22.0%. Being physically active at the first measurement time point was associated with a 38% reduction in the risk of reporting NCCP-related disability in the following 6 months (ρ = .047). This association remained significant after controlling for confounding variables. CONCLUSIONS: Being physically active seems to have a protective effect on the occurrence of NCCP-related disability in the 6 months following an emergency department visit with NCCP. These results point to the importance of further exploring the benefits of physical activity in this population.

A closer look at the relationships between panic attacks, emergency department visits and non-cardiac chest pain.

This study examined the prevalence of emergency department visits prompted by panic attacks in patients with non-cardiac chest pain. A validated structured telephone interview was used to assess panic attacks and their association with the emergency department consultation in 1327 emergency department patients with non-cardiac chest pain. Patients reported at least one panic attack in the past 6 months in 34.5 per cent (95% confidence interval: 32.0%-37.1%) of cases, and 77.1 per cent (95% confidence interval: 73.0%-80.7%) of patients who reported panic attacks had visited the emergency department with non-cardiac chest pain following a panic attack. These results indicate that panic attacks may explain a significant proportion of emergency department visits for non-cardiac chest pain.

The Revised-Panic Screening Score for emergency department patients with noncardiac chest pain.

OBJECTIVES: We sought to reduce the 90% rate of missed diagnoses of panic-like anxiety (panic attacks with or without panic disorder) among emergency department patients with low risk noncardiac chest pain by validating and improving the Panic Screening Score (PSS). METHOD: A total of 1,102 patients with low risk noncardiac chest pain were prospectively and consecutively recruited in two emergency departments. Each patient completed a telephone interview that included the PSS, a brief 4-item screening instrument, new candidate predictors of panic-like anxiety, and the Anxiety Disorder Interview for the Diagnostic and Statistical Manual of Mental Disorders. Fourth Edition to identify panic-like anxiety. RESULTS: The original 4-item PSS demonstrated a sensitivity of 51.8% (95% CI [48.4, 57.0]) and a specificity of 74.8% (95% CI [71.3, 78.1]) for panic-like anxiety. Analyses prompted the development of the Revised-PSS; this 6-item instrument was 19.1% (95% CI [12.7, 25.5]) more sensitive than the original PSS in identifying panic-like anxiety in this sample (χ2(1, N = 351) = 23.89 p < .001) while maintaining a similar specificity (χ2(1, N = 659) = 0.754, p = .385; 0.4%, 95% CI [-3.6, 4.5]). The discriminant validity of the Revised-PSS proved stable over the course of a 10-fold cross-validation. CONCLUSIONS: The Revised-PSS has significant potential for improving identification of panic-like anxiety in emergency department patients with low risk noncardiac chest pain and promoting early access to treatment. External validation and impact analysis of the Revised-PSS are warranted prior to clinical implementation. (PsycINFO Database Record

Work Absenteeism and Presenteeism Loss in Patients With Non-Cardiac Chest Pain.

OBJECTIVE: To assess work absenteeism and presenteeism, and to identify biopsychosocial predictors of these outcomes in workers with non-cardiac chest pain (NCCP). METHODS: This retrospective cohort study included 375 active workers consulting in an emergency room for NCCP. RESULTS: About 66% (247/375) of participants reported work absenteeism in the 3 months preceding the consultation, while 36% (134/375) reported presenteeism during the same period. A family income >$29,999, and reporting at least a mild impact of chest pain on family functioning, social functioning, or physical activities, were associated with work absenteeism. Presenteeism was associated with younger age, symptoms of depression, and heart-focused anxiety. CONCLUSIONS: Work absenteeism and presenteeism are highly prevalent among patients with NCCP. Family income and impacts of NCCP on functioning, are associated with increased occupational burden in these patients.

Heart-focused anxiety and health care seeking in patients with non-cardiac chest pain: A prospective study.

OBJECTIVES: This study aimed to estimate the incidence of medical consultations six months after an emergency department (ED) consultation for non-cardiac chest pain (NCCP). It also investigated the role of heart-focused anxiety (HFA) and other factors in predicting an increased healthcare utilization in these patients. METHOD: This was a prospective study of 428 patients who came to an ED with NCCP. Patients completed an interview and questionnaires assessing HFA, psychological distress, the characteristics of NCCP, and comorbidities. Their medical consultations were assessed by telephone interview six months later. The contribution of each factor was assessed using a binomial negative regression. RESULTS: Eighty-three percent of patients reported at least one medical consultation (mean=3.1, standard deviation=3.9). HFA (incident rate ratio 1.01; 95% CI, 1.00-1.02), the presence of a medical condition (2.14; 1.51-3.03), NCCP frequency (1.49; 1.16-1.91) and NCCP-related interference (1.08; 1.04-1.13) were predictive of further medical consultations. CONCLUSIONS: A significant proportion of patients with NCCP are at risk of multiple medical consultations following discharge from the ED. HFA appears as a determinant of medical consultations after controlling for multiple confounding factors.

Fasting induces astroglial plasticity in the olfactory bulb glomeruli of rats.

The detection of food odors by the olfactory system, which plays a key role in regulating food intake and elaborating the hedonic value of food, is reciprocally influenced by the metabolic state. Fasting increases olfactory performance, notably by increasing the activity of olfactory bulb (OB) neurons. The glutamatergic synapses between olfactory sensory neurons and mitral cells in the OB glomeruli are regulated by astrocytes, periglomerular neurons, and centrifugal afferents. We compared the expansion of astroglial processes by quantifying GFAP-labeled areas in fed and fasted rats to see whether OB glomerular astrocytes are involved in the metabolic sensing and adaptation of the olfactory system. Glomerular astroglial spreading was much greater in all OB regions of rats fasted for 17 hr than in controls. Intra-peritoneal administration of the anorexigenic peptide PYY3-36 or glucose in 17 hr-fasted rats respectively decreased their food intake or restored their glycemia, and reversed the fasting-induced astroglial spreading. Direct application of the orexigenic peptides ghrelin or NPY to OB slices increased astroglial spreading, whereas PYY3-36 resulted in astroglial retraction, in agreement with the in vivo effects of fasting and satiety on glomerular astrocytes. Thus the morphological plasticity of OB glomerular astrocytes depends on the metabolic state of the rats and is influenced by peptides that regulate food intake. This plasticity may be part of the mechanism by which the olfactory system adapts to food intake.

Lipids in maternal diet influence yolk hormone levels and post-hatch neophobia in the domestic chick.

We assessed whether the ratio of dietary n-6/n-3 polyunsaturated fatty acids (PUFA) during egg formation engenders transgenerational maternal effects in domestic chicks. We analyzed yolk lipid and hormone concentrations, and HPA-axis activity in hens fed a control diet (high n-6/n-3 ratio) or a diet enriched in n-3 PUFAs (low n-6/n-3 ratio) for 6 consecutive weeks. Their chicks were tested for neophobia during the first week of life. We found higher corticosterone metabolites in droppings of hens fed the diet enriched in n-3 and significantly higher concentrations of yolk progesterone, androstenedione, and estradiol in their eggs compared to controls. Chicks of hens fed the n-3 enriched diet showed a lower body mass at hatch than controls and expressed higher neophobia when exposed to a novel object. These results add support to the hypothesis that the nutritional state of female birds produces variation in yolk hormone levels and engender maternal effects.