Neural and behavioural correlates of repeated social defeat

© 2018 The Author(s). Dominance hierarchies are common across the animal kingdom and have important consequences for reproduction and survival. Animals of lower social status cope with repeated social defeat using proactive and reactive behaviours. However, there remains a paucity of information on how an individual\u27s coping behaviours changes over time or what neural mechanisms are involved. We used a resident-intruder paradigm in the African cichlid fish Astatotilapia burtoni to investigate the neural correlates of these two opposing behaviour groups. Fish initially used both proactive and reactive behaviours, but had a dramatic increase in use of proactive behaviours during the third interaction, and this was followed by cessation of proactive behaviours and exclusive use of reactive coping. By quantifying neural activation in socially-relevant brain regions, we identify a subset of brain nuclei, including those homologous to the mammalian amygdala, showing higher activation in fish displaying proactive but not reactive behaviours. Fish displaying reactive behaviours had greater neural activation in the superior raphe, suggesting a possible conserved function during social defeat across vertebrates. These data provide the first evidence on the involvement of specific brain regions underlying proactive and reactive coping in fishes, indicating that these nuclei have conserved functions during social defeat across taxa

Swim bladder morphology changes with female reproductive state in the mouth-brooding African cichlid Astatotilapia burtoni

© 2017. Published by The Company of Biologists Ltd. Journal of Experimental Biology. Mouth brooding is an extreme form of parental care in which the brooding parent carries the developing young in their buccal cavity for the duration of development. Brooding fish need to compensate for the brood weight on the anterior portion of their body. For fishes with a compartmentalized swim bladder, gas distribution between the chambers may aid in regulating buoyancy during brooding. To test this hypothesis, we took radiographs of Astatotilapia burtoni to compare the swim bladder morphology of gravid, mouth-brooding and recovering females. Following spawning, females carry developing fish in their buccal cavity for ∼2 weeks, resulting in a larger and rounder anterior swim bladder compartment. Comparatively, the swim bladder of gravid females is long and cylindrical. Using small beads to mimic brood weight and its effects on female buoyancy, swim bladder changes were induced that resembled those observed during brooding. Immediately after releasing their fry, brooding females swim at a positive angle of attack but correct their swimming posture to normal within 5 min, suggesting a rapid change in swim bladder gas distribution. These data provide new insights into how swim bladder morphology and swimming behavior change during mouth brooding, and suggest a compartmentalized swim bladder may be a morphological adaptation for mouth brooding

The Transcriptional Response of Drosophila melanogaster to Infection with the Sigma Virus (Rhabdoviridae)

Bacterial and fungal infections induce a potent immune response in Drosophila melanogaster, but it is unclear whether viral infections induce an antiviral immune response. Using microarrays, we examined the changes in gene expression in Drosophila that occur in response to infection with the sigma virus, a negative-stranded RNA virus (Rhabdoviridae) that occurs in wild populations of D. melanogaster. We detected many changes in gene expression in infected flies, but found no evidence for the activation of the Toll, IMD or Jak-STAT pathways, which control immune responses against bacteria and fungi. We identified a number of functional categories of genes, including serine proteases, ribosomal proteins and chorion proteins that were overrepresented among the differentially expressed genes. We also found that the sigma virus alters the expression of many more genes in males than in females. These data suggest that either Drosophila do not mount an immune response against the sigma virus, or that the immune response is not controlled by known immune pathways. If the latter is true, the genes that we identified as differentially expressed after infection are promising candidates for controlling the host's response to the sigma virus

Galanin neuron activation in feeding, parental care, and infanticide in a mouthbrooding African cichlid fish

Galanin is a conserved neuropeptide involved in parental care and feeding. While galanin is known to mediate parental care and infanticide in rodents, its role in parental care and feeding behaviors in other taxa, particularly fishes, remains poorly understood. Mouthbrooding is an extreme form of parental care common in fishes in which caregivers carry offspring in their buccal cavity for the duration of development, resulting in obligatory starvation. In the cichlid fish Astatotilapia burtoni, females brood their young for ~2 wks and perform maternal care after release by collecting them into their mouth when threatened. However, females will cannibalize their brood after ~5 days. To examine the role of gal in feeding and maternal care, we collected mouthbrooding, fed, and starved females, as well as those displaying post-release maternal care and infanticide behaviors. Activation of gal neurons in the preoptic area (POA) was associated with parental care, providing the first link between gal and offspring-promoting behaviors in fishes. In contrast, activation of gal neurons in the lateral tuberal nucleus (NLT), the Arcuate homolog, was associated with feeding and infanticide. Overall, these data suggest gal is functionally conserved across vertebrate taxa with POA gal neurons promoting maternal care and Arc/NLT gal neurons promoting feeding

Swim bladder morphology changes with female reproductive state in the mouth-brooding African cichlid Astatotilapia burtoni

© 2017. Published by The Company of Biologists Ltd. Journal of Experimental Biology. Mouth brooding is an extreme form of parental care in which the brooding parent carries the developing young in their buccal cavity for the duration of development. Brooding fish need to compensate for the brood weight on the anterior portion of their body. For fishes with a compartmentalized swim bladder, gas distribution between the chambers may aid in regulating buoyancy during brooding. To test this hypothesis, we took radiographs of Astatotilapia burtoni to compare the swim bladder morphology of gravid, mouth-brooding and recovering females. Following spawning, females carry developing fish in their buccal cavity for ∼2 weeks, resulting in a larger and rounder anterior swim bladder compartment. Comparatively, the swim bladder of gravid females is long and cylindrical. Using small beads to mimic brood weight and its effects on female buoyancy, swim bladder changes were induced that resembled those observed during brooding. Immediately after releasing their fry, brooding females swim at a positive angle of attack but correct their swimming posture to normal within 5 min, suggesting a rapid change in swim bladder gas distribution. These data provide new insights into how swim bladder morphology and swimming behavior change during mouth brooding, and suggest a compartmentalized swim bladder may be a morphological adaptation for mouth brooding

Scour Detection Using Infrasound: A case study of the Feather River Bridge of State Highway 20 (the 10th Street Bridge) in Yuba City, CA

Scour at bridge piers and abutments is a commonly encountered issue for both military and civil works. For bridges deemed to be scour critical, additional monitoring may be specified including additional inspections beyond law requirements, portable monitoring systems, and/or fixed monitoring systems with visual inspections as the most common. Current monitoring systems are not true remote systems in the sense that they must be installed on or near the bridge, such as around bridge piers or abutments in the channel bed or on the piers and abutments themselves, and are susceptible to damage. Ongoing studies by the US Army Engineer Research and Development Center (ERDC) are investigating infrasound, low frequency acoustics, as a means of scour detection and assessment at bridge piers. These passive infrasound arrays can monitor structures at distances up to 25 km and greater depending on signal strength. Presented are a field study and initial results from a scour critical bridge in northern California

Reproductive state-dependent plasticity in the visual system of an African cichlid fish

Visual communication is used widely across the animal kingdom to convey crucial information about an animals\u27 identity, reproductive status, and sex. Although it is well-demonstrated that auditory and olfactory sensitivity can change with reproductive state, fewer studies have tested for plasticity in the visual system, a surprising detail since courtship and mate choice behaviors in many species are largely dependent on visual signals. Here, we tested for reproductive state-dependent plasticity in the eye of the cichlid fish Astatotilapia burtoni using behavioral, gene expression, neural activation, and electrophysiology techniques. Males court ovulated females more intensely than gravid females, and ovulated females were more responsive to male courtship behaviors than gravid females. Using electroretinography to measure visual sensitivity in dark-adapted fish, we revealed that gravid, reproductively-ready females have increased visual sensitivity at wavelengths associated with male courtship coloration compared to non-gravid females. After ovulation was hormonally induced, female\u27s spectral sensitivity further increased compared to pre-injection measurements. This increased sensitivity after hormone injection was absent in non-gravid females and in males, suggesting an ovulation-triggered increase in visual sensitivity. Ovulated females had higher mRNA expression levels of reproductive neuromodulatory receptors (sex-steroids; gonadotropins) in the eye than nonovulated females, whereas males had similar expression levels independent of reproductive/social state. In addition, female mate choice-like behaviors positively correlated with expression of gonadotropin system receptors in the eye. Collectively, these data provide crucial evidence linking endocrine modulation of visual plasticity to mate choice behaviors in females

Laparoscopic versus open sacrocolpopexy for treatment of prolapse of the apical segment of the vagina: a systematic review and meta-analysis

Introduction: Pelvic organ prolapse is showing an increasing prevalence (3 – 50 %). The gold standard treatment of apical prolapse is sacrocolpopexy which can be performed via minimal access (laparoscopy or robotics) or open approaches. The aim of this review was to appraise the effectiveness of minimal access surgery versus the open approach in the treatment of apical prolapse. Methods: Keywords were searched in: CINAHL, MEDLINE, CENTRAL, Cochrane MDSG Trials Register, Cochrane Library, Current Controlled Trials, ClinicalTrials.gov, WHO International Trials Registry Platform search portal, LILACS, and Google Scholar databases. Data up to 31 April 2014 were considered. Randomized and nonrandomized controlled trials evaluating all women who underwent minimally invasive sacropexy (MISC) and open sacropexy (OSC) were included. A data extraction tool was used for data collection. MISC was compared with OSC using narrative analysis and meta-analysis (RevMan) where appropriate. Results: MISC and OSC were compared in 12 studies involving 4,757 participants. MISC and OSC were equally effective in terms of point-C POP-Q measurements and recurrence rate. MISC was associated with a lower transfusion rate (odds ratio 0.41, 95 % CI 0.20 – 0.83), shorter length of hospital stay (mean difference −1.57 days, 95 % CI −1.91 – −1.23 days), and less blood loss (mean difference −113.27 mL, 95 % CI −163.67 – −62.87 mL) but a longer operating time (mean difference 87.47, 95 % CI 58.60 – 116.34, p < 0.0001). Conclusions: MISC showed similar anatomic results to OSC with a lower transfusion rate, shorter length of hospital stay and less blood loss. The rate of other complications was similar between the approaches. Cautious interpretation of results is advised due to risk of bias caused by the inclusion of nonrandomized studies