Effect of a Territorial Challenge on the Steroid Profile of a Juvenile Songbird.

Aggression is a social behavior that is critical for survival and reproduction. In adults, circulating gonadal hormones, such as androgens, act on neural circuits to modulate aggressive interactions, especially in reproductive contexts. In many species, individuals also demonstrate aggression before reaching gonadal maturation. Adult male song sparrows, Melospiza melodia, breed seasonally but maintain territories year-round. Juvenile (hatch-year) males aggressively compete for territory ownership during their first winter when circulating testosterone is low. Here, we characterized the relationship between the steroid milieu and aggressive behavior in free-living juvenile male song sparrows in winter. We investigated the effect of a 10 min simulated territorial intrusion (STI) on behavior and steroid levels in blood, 10 microdissected brain regions, and four peripheral tissues (liver, pectoral muscle, adrenal glands, and testes). Using liquid chromatography-tandem mass spectrometry (LC-MS/MS), we quantified 12 steroids: pregnenolone, progesterone, corticosterone, 11-dehydrocorticosterone, dehydroepiandrosterone, androstenedione, testosterone, 5α-dihydrotestosterone, 17ß-estradiol, 17α-estradiol, estrone, and estriol. We found that juvenile males are robustly aggressive, like adult males. An STI increases progesterone and corticosterone levels in blood and brain and increases 11-dehydrocorticosterone levels in blood only. Pregnenolone, androgens, and estrogens are generally non-detectable and are not affected by an STI. In peripheral tissues, steroid concentrations are very high in the adrenals. These data suggest that adrenal steroids, such as progesterone and corticosterone, might promote juvenile aggression and that juvenile and adult songbirds might rely on distinct neuroendocrine mechanisms to support similar aggressive behaviors.

The ergonomic impact of a mattress lift tool and bottom sheet type on hotel room cleaners while making beds.

The purpose of this study was to quantify biomechanical and cardiovascular exposure while making beds with and without interventions (mattress lift tool and fitted sheet). Sixteen female hotel room cleaners participated in this multifactorial (tool and sheet) laboratory study of crossover design. Exertion in the upper extremity (<2) and back (<3) was consistently lower when using the tool and fitted sheet (p < 0.05). The average number of lifts per bed was reduced by 48% with an 18 s increase in cycle time per bed. Peak forearm flexor activity was significantly lower when using a tool(p < 0.05). Spinal lateral plane range of motion (p < 0.02) and maximum twisting velocity (p < 0.03) were lowest using the tool and fitted sheet together. Interventions such as a mattress lift tool used with a fitted sheet reduced the number of mattress lifts and lowered perceived exertion among hotel room cleaners while making beds.

Effect of probiotic bacteria on the intestinal microbiota in irritable bowel syndrome.

BACKGROUND AND AIM: In irritable bowel syndrome (IBS), the gut microbiota may be altered. Probiotic bacteria appear to be therapeutically effective. We characterized the mucosa-associated microbiota, and determined the clinical and microbiological effects of orally administered probiotic bacteria, in patients with IBS. METHODS: Mucosal microbiota from rectal biopsies of IBS patients and controls were assessed on the V1 and V2 variable regions of the 16S ribosomal RNA gene amplified using 454 pyrosequencing. Clinical symptoms and changes in mucosal microbiota were assessed in IBS patients before and after 4 weeks of treatment with probiotic mix VSL#3. RESULTS: Ten IBS subjects (eight female; mean age 46 years) were included. At week 4 of probiotic therapy, six patients showed symptom improvement on global symptom assessment compared with baseline (P = 0.031). Before therapy, intestinal microbiota of IBS subjects differed significantly from that of healthy controls, with less diversity and evenness than controls (n = 9; P < 0.05), increased abundance of Bacteroidetes (P = 0.014) and Synegitestes (P = 0.017), and reduced abundance of Actinobacteria (P = 0.004). The classes Flavobacteria (P = 0.028) and Epsilonproteobacteria (P = 0.017) were less enriched in IBS. Abundance differences were largely consistent from the phylum to genus level. Probiotic treatment in IBS patients was associated with a significant reduction of the genus Bacteroides (all taxonomy levels; P < 0.05) to levels similar to that of controls. CONCLUSION: In this pilot study, global and deep molecular analysis demonstrates an altered mucosal microbiota composition in IBS. Probiotic leads to detectable changes in the microbiota. These effects of probiotic bacteria may contribute to their therapeutic benefit.

Effect of electroacupuncture on visceral hyperalgesia, serotonin and fos expression in an animal model of irritable bowel syndrome.

BACKGROUND/AIMS: While it is well established that acupuncture relieves somatic pain, its therapeutic effect on visceral pain such as irritable bowel syndrome (IBS) is unclear. We evaluated the effect of acupuncture in treating visceral hyperalgesia in an animal model. METHODS: Sprague-Dawley rats (n = 8 per group) with prior neonatal maternal separation stress were randomly allocated to receive 3-day treatment of either electroacupuncture (EA) or sham acupuncture at acupoint ST-36. Another group of rats without prior maternal separation was included as non-handled controls. Colorectal distension was performed on the day after acupuncture treatment. The 3 groups were compared for pain threshold as determined by abdominal withdrawal reflex and visceromotor response as measured by electromyogram. Colon, spinal cord, and brainstem were sampled for topographic distribution and quantitative assessment of serotonin and Fos expression by immunohistochemistry. RESULTS: Rats in EA group had significantly higher pain threshold compared to those in sham acpuncture group (25.0 +/- 5.7 mmHg vs 18.7 +/- 5.2 mmHg, p = 0.01) and it was comparable with that of non-handled treatment naïve controls (29.4 +/- 9.3 mmHg, p = 0.28). They also had lower visceromotor response as measured by electromyogram compared to those received sham acupuncture at all colorectal distension pressures. EA significantly suppressed Fos expression in doral raphe nuclei of brainstem, superficial dorsal horn of spinal cord and colonic epithelium but suppressed 5-HT expression only in brainstem and spinal cord. CONCLUSIONS: Electro acupuncture attenuates visceral hyperlagesia through down-regulation of central serotonergic activities in the brain-gut axis.