Consistent changes in muscle metabolism underlie dive performance across multiple lineages of diving ducks

Diving animals must sustain high activity with limited O₂ stores to successfully capture prey. Studies suggest that increasing body O₂ stores supports breath-hold diving, but less is known about metabolic specializations that underlie underwater locomotion. We measured maximal activities of 10 key enzymes in locomotory muscles (gastrocnemius and pectoralis) to identify biochemical changes associated with diving in pathways of oxidative and substrate-level phosphorylation and compared them across three groups of ducks—the longest diving sea ducks (eight spp.), the mid-tier diving pochards (three spp.) and the non-diving dabblers (five spp.). Relative to dabblers, both diving groups had increased activities of succinate dehydrogenase and cytochrome c oxidase, and sea ducks further showed increases in citrate synthase (CS) and hydroxyacyl-CoA dehydrogenase (HOAD). Both diving groups had relative decreases in capacity for anaerobic metabolism (lower ratio of lactate dehydrogenase to CS), with sea ducks also showing a greater capacity for oxidative phosphorylation and lipid oxidation (lower ratio of pyruvate kinase to CS, higher ratio of HOAD to hexokinase). These data suggest that the locomotory muscles of diving ducks are specialized for sustaining high rates of aerobic metabolism, emphasizing the importance of body O₂ stores for dive performance in these species

A double blind randomized trial of wound infiltration with ropivacaine after breast cancer surgery with axillary nodes dissection

<p>Abstract</p> <p>Background</p> <p>The effect of local infiltration after breast surgery is controversial. This prospective double blind randomized study sought to document the analgesic effect of local anaesthetic infiltration after breast cancer surgery.</p> <p>Methods</p> <p>Patients scheduled for mastectomy or tumorectomy and axillary nodes dissection had immediate postoperative infiltration of the surgical wound with 20 ml of ropivacaine 7.5 mg.ml^-1or isotonic saline. Pain was assessed on a visual analogue scale at H2, H4, H6, H12, H24, H72, and at 2 month, at rest and on mobilization of the arm. Patient'comfort was evaluated with numerical 0-3 scales for fatigue, quality of sleep, state of mood, social function and activity.</p> <p>Results</p> <p>Twenty-two and 24 patients were included in the ropivacaine and saline groups respectively. Postoperative pain was lower at rest and on mobilization at 2, 4 and 6 hour after surgery in the ropivacaine group. No other difference in pain intensity and patient 'comfort scoring was documented during the first 3 postoperative days. Patients did not differ at 2 month for pain and comfort scores.</p> <p>Conclusion</p> <p>Single shot infiltration with ropivacaine transiently improves postoperative pain control after breast cancer surgery.</p> <p>Trial registration number</p> <p><a href="http://www.clinicaltrials.gov/ct2/show/NCT01404377">NCT01404377</a></p

Malaria Infections Do Not Compromise Vaccine-Induced Immunity against Tuberculosis in Mice

BACKGROUND: Given the considerable geographic overlap in the endemic regions for malaria and tuberculosis, it is probable that co-infections with Mycobacterium tuberculosis and Plasmodium species are prevalent. Thus, it is quite likely that both malaria and TB vaccines may be used in the same populations in endemic areas. While novel vaccines are currently being developed and tested individually against each of these pathogens, the efficacy of these vaccines has not been evaluated in co-infection models. To further assess the effectiveness of these new immunization strategies, we investigated whether co-infection with malaria would impact the anti-tuberculosis protection induced by four different types of TB vaccines in a mouse model of pulmonary tuberculosis. PRINCIPAL FINDINGS: Here we show that the anti-tuberculosis protective immunity induced by four different tuberculosis vaccines was not impacted by a concurrent infection with Plasmodium yoelii NL, a nonlethal form of murine malaria. After an aerogenic challenge with virulent M. tuberculosis, the lung bacterial burdens of vaccinated animals were not statistically different in malaria infected and malaria naïve mice. Multi-parameter flow cytometric analysis showed that the frequency and the median fluorescence intensities (MFI) for specific multifunctional T (MFT) cells expressing IFN-γ, TNF-α, and/or IL-2 were suppressed by the presence of malaria parasites at 2 weeks following the malaria infection but was not affected after parasite clearance at 7 and 10 weeks post-challenge with P. yoelii NL. CONCLUSIONS: Our data indicate that the effectiveness of novel TB vaccines in protecting against tuberculosis was unaffected by a primary malaria co-infection in a mouse model of pulmonary tuberculosis. While the activities of specific MFT cell subsets were reduced at elevated levels of malaria parasitemia, the T cell suppression was short-lived. Our findings have important relevance in developing strategies for the deployment of new TB vaccines in malaria endemic areas

Ecologically Appropriate Xenobiotics Induce Cytochrome P450s in Apis mellifera

BACKGROUND: Honey bees are exposed to phytochemicals through the nectar, pollen and propolis consumed to sustain the colony. They may also encounter mycotoxins produced by Aspergillus fungi infesting pollen in beebread. Moreover, bees are exposed to agricultural pesticides, particularly in-hive acaricides used against the parasite Varroa destructor. They cope with these and other xenobiotics primarily through enzymatic detoxificative processes, but the regulation of detoxificative enzymes in honey bees remains largely unexplored. METHODOLOGY/PRINCIPAL FINDINGS: We used several approaches to ascertain effects of dietary toxins on bee susceptibility to synthetic and natural xenobiotics, including the acaricide tau-fluvalinate, the agricultural pesticide imidacloprid, and the naturally occurring mycotoxin aflatoxin. We administered potential inducers of cytochrome P450 enzymes, the principal biochemical system for Phase 1 detoxification in insects, to investigate how detoxification is regulated. The drug phenobarbital induces P450s in many insects, yet feeding bees with phenobarbital had no effect on the toxicity of tau-fluvalinate, a pesticide known to be detoxified by bee P450s. Similarly, no P450 induction, as measured by tau-fluvalinate tolerance, occurred in bees fed xanthotoxin, salicylic acid, or indole-3-carbinol, all of which induce P450s in other insects. Only quercetin, a common pollen and honey constituent, reduced tau-fluvalinate toxicity. In microarray comparisons no change in detoxificative gene expression was detected in phenobarbital-treated bees. However, northern blot analyses of guts of bees fed extracts of honey, pollen and propolis showed elevated expression of three CYP6AS P450 genes. Diet did not influence tau-fluvalinate or imidacloprid toxicity in bioassays; however, aflatoxin toxicity was higher in bees consuming sucrose or high-fructose corn syrup than in bees consuming honey. CONCLUSIONS/SIGNIFICANCE: These results suggest that regulation of honey bee P450s is tuned to chemicals occurring naturally in the hive environment and that, in terms of toxicological capacity, a diet of sugar is not equivalent to a diet of honey

Short-term, but not acute, intake of New Zealand blackcurrant extract improves insulin sensitivity and free-living postprandial glucose excursions in individuals with overweight or obesity

Abstract: Impaired postprandial glucose handling and low-grade systemic inflammation are risk factors for developing insulin resistance in individuals with overweight or obesity. Acute ingestion of anthocyanins improves postprandial glucose responses to a single carbohydrate-rich meal under strictly controlled conditions. Purpose: Examine whether acute and short-term supplementation with anthocyanin-rich New Zealand blackcurrant (NZBC) extract can improve postprandial glucose responses to mixed-macronutrient meals. Methods: Twenty-five overweight (BMI > 25 kg m2) sedentary individuals participated in one of the following double-blinded, randomised controlled trials: (1) ingestion of 600 mg NZBC extract or placebo prior to consumption of a high-carbohydrate, high-fat liquid meal (n = 12); (2) 8-days supplementation with NZBC extract (600 mg day−1) or placebo, with insulin sensitivity and markers of inflammation assessed on day-7, and free-living postprandial glucose (continuous glucose monitoring) assessed on day-8 (n = 13). Results: A single dose of NZBC extract had no effect on 3 h postprandial glucose, insulin or triglyceride responses. However, in response to short-term NZBC extract supplementation insulin sensitivity was improved (+ 22%; P = 0.011), circulating C-reactive protein concentrations decreased (P = 0.008), and free-living postprandial glucose responses to both breakfast and lunch meals were reduced (− 9% and − 8%, respectively; P < 0.05), compared to placebo. Conclusion: These novel results indicate that repeated intake, rather than a single dose of NZBC extract, is required to induce beneficial effects on insulin sensitivity and postprandial glucose handling in individuals with overweight or obesity. Continuous glucose monitoring enabled an effect of NZBC extract to be observed under free-living conditions and highlights the potential of anthocyanin-rich supplements as a viable strategy to reduce insulin resistance

Insomnia severity as a mediator of the association between mental health symptoms and alcohol use in young adult veterans

PurposePrior research has documented associations between mental health and alcohol use, mental health and insomnia, and insomnia and alcohol use. This study examined insomnia severity as a mediator of the association between mental health and alcohol-related outcomes in young adult veterans.ProceduresVeterans aged 18-34 years (N=622, 83% male) who reported drinking in the past year completed assessments at baseline and one-month follow-up as part of a larger intervention trial. Participants reported symptoms of depression and posttraumatic stress disorder (PTSD) at baseline, insomnia severity at one month, and alcohol use and related consequences at baseline and one month. Mediation analyses using bootstrapped confidence intervals were used to examine the indirect effects of baseline mental health symptoms on alcohol-related outcomes at one month via insomnia severity.Main findingsInsomnia severity was associated with both drinking quantity and alcohol-related consequences. Greater depressive (but not PTSD) symptoms were associated directly with more alcohol-related consequences. Neither depressive nor PTSD symptoms had direct effects on drinking quantity when controlling for the other mental health symptoms (e.g., depressive symptoms did not predict drinking quantity when controlling for symptoms of PTSD). However, symptoms of depression and PTSD predicted drinks per week and alcohol-related consequences indirectly through insomnia severity.ConclusionsSymptoms of depression and PTSD increase risk for alcohol use and related consequences in part by increasing symptoms of insomnia. Findings suggest that insomnia may be an appropriate target for prevention and intervention efforts among heavy-drinking Veterans reporting symptoms of depression or PTSD