Cage Control Research Articles

Biotic resistance to the infiltration of natural benthic habitats: Examining the role of predation in the distribution of the invasive ascidian Botrylloides violaceus

Anthropogenic marine habitats, such as marinas and breakwaters, are frequently colonized by nonindigenous species (NIS). Comparative studies show that few sessile NIS are found in nearby natural habitats, but little is known about the processes affecting the spread of NIS into these habitats. In southern British Columbia, the invasive colonial ascidian Botrylloides violaceus is widespread, but is far more common on man-made structures at marinas and aquaculture facilities than adjacent natural rocky reefs. To determine whether predation by native species, one element of biotic resistance, influences the successful infiltration of B. violaceus into natural benthic habitats, we conducted a series of predator exclusion experiments. Established adult colonies and newly settled juvenile B. violaceus were transplanted onto replicate PVC panels and deployed at marina pilings and adjacent natural rocky reefs at two locations. Panels were assigned to caged, uncaged, and procedural control treatments to test whether predator exclusion changed survivorship. Both juvenile and adult ascidian survival was significantly lower in uncaged treatments, suggesting that predation can limit the abundance and distribution of this species. Results were similar between piling and rocky reef habitats regardless of life stage and our results suggest that adult and juvenile B. violaceus are vulnerable to predation in both habitats studied. If B. violaceus propagules can disperse from dock floats and infiltrate adjacent natural rock, biotic resistance, through predation by native species, may diminish the likelihood of successful colonization in these habitats. Ensuring that natural habitats and native benthic communities remain healthy and intact may reduce the likelihood that invasive ascidians will spread beyond anthropogenic introduction sites where they can dominate the fouling community.

Sketch-based surface design using malleable curve networks

We present a new 3D surface modeling approach that enables curve-based creation and modification of smooth surfaces by sketching. The key feature of the proposed methods is a two-way communication between the user-designed curve networks and the generated surfaces. A user-drawn curve network serves as a control cage, from which a subdivision surface is generated. The subdivision surface is updated to match the curve network while minimizing the curvature variation throughout the surface. Surface fairness is controlled independently to modify the curve network into suitable configurations that guarantee a smooth underlying surface. This approach enables a concurrent modeling of the curve network and the underlying surface, thus eliminating the need for a laborious, iterative adjustment of the curve network for smooth surface creation. We demonstrate our approach with example models, and evaluate it with a user study.

Comparison of the activation of somatostatin- and neuropeptide Y-containing neuronal populations of the rat amygdala following two different anxiogenic stressors

Rats exposed to the odor of a predator or to the elevated plus maze express fear behaviors without a prior exposure to either stimulus. The expression of innate fear provides for an ideal model of anxiety which can aid in the elucidation of brain circuits involved in anxiety-related behaviors. The current experiments compared activation of neuropeptide-containing neuronal populations in the amygdala of rats exposed to either the elevated plus maze (EPM; 5min) versus home cage controls, or predator ferret odor versus butyric acid, or no odor (30min). Sections of the brains were prepared for dual-labeled immunohistochemistry and counts of c-Fos co-localized with somatostatin (SOM) or neuropeptide Y (NPY) were made in the basolateral (BLA), central (CEA), medial (MEA) nuclei of the amygdala. Ferret odor and butyric acid exposure significantly decreased the percentage of SOM‐positive neurons also immunoreactive for c-Fos in the anterior BLA compared to controls, whereas EPM exposure yielded a significant increase in the activation of SOM-positive neurons versus home cage controls. In the CEA, ferret odor and butyric exposure significantly decreased the percentage of SOM-positive neurons also immunoreactive for c-Fos compared to no-odor controls whereas EPM exposure yielded no change versus controls. In the MEA, both ferret odor exposure and EPM exposure resulted in increased SOM co-localized with c-Fos compared to control groups whereas NPY co-localized with c-Fos occurred following ferret odor exposure, but not EPM exposure. These results indicate that phenotypically distinct neuronal populations of the amygdala are differentially activated following exposure to different anxiogenic stimuli. These studies further elucidate the fundamental neurocircuitry of anxiety and could possibly explain the differential behavioral effects of predator versus novelty-induced stress.

Contribution of Social Isolation, Restraint, and Hindlimb Unloading to Changes in Hemodynamic Parameters and Motion Activity in Rats

The most accepted animal model for simulation of the physiological and morphological consequences of microgravity on the cardiovascular system is one of head-down hindlimb unloading. Experimental conditions surrounding this model include not only head-down tilting of rats, but also social and restraint stresses that have their own influences on cardiovascular system function. Here, we studied levels of spontaneous locomotor activity, blood pressure, and heart rate during 14 days under the following experimental conditions: cage control, social isolation in standard rat housing, social isolation in special cages for hindlimb unloading, horizontal attachment (restraint), and head-down hindlimb unloading. General activity and hemodynamic parameters were continuously monitored in conscious rats by telemetry. Heart rate and blood pressure were both evaluated during treadmill running to reveal cardiovascular deconditioning development as a result of unloading. The main findings of our work are that: social isolation and restraint induced persistent physical inactivity, while unloading in rats resulted in initial inactivity followed by normalization and increased locomotion after one week. Moreover, 14 days of hindlimb unloading showed significant elevation of blood pressure and slight elevation of heart rate. Hemodynamic changes in isolated and restrained rats largely reproduced the trends observed during unloading. Finally, we detected no augmentation of tachycardia during moderate exercise in rats after 14 days of unloading. Thus, we concluded that both social isolation and restraint, as an integral part of the model conditions, contribute essentially to cardiovascular reactions during head-down hindlimb unloading, compared to the little changes in the hydrostatic gradient.

Aerobic exercise is the critical variable in an enriched environment that increases hippocampal neurogenesis and water maze learning in male C57BL/6J mice

Previous studies have shown that housing mice with toys and running wheels increases adult hippocampal neurogenesis and enhances performance on the water maze. However, the relative contribution of running versus enrichment to the neurogenic and pro-cognitive effects is not clear. Recently, it was demonstrated that enrichment devoid of running wheels does not significantly enhance adult hippocampal neurogenesis in female C57BL/6J mice. However, novel toys were not rotated into the cages, and dietary enrichment was not included, so it could be argued that the environment was not enriched enough. In addition, only females were studied, and animals were group-housed, making it impossible to record individual running behavior or to determine the time spent running versus exploring the toys. Therefore, we repeated the study in singly housed male C57BL/6J mice and enhanced enrichment by rotating novel tactile, visual, dietary, auditory, and vestibular stimuli into the cages. Mice were housed for 32days in one of four groups: running-only, enrichment-only, running plus enrichment, and standard cage. The first 10days bromodeoxyuridine (BrdU) was administered to label dividing cells. The last 5days mice were tested on the water maze, and then euthanized to measure number of BrdU cells co-labeled with neuronal nuclear marker (NeuN) in the dentate gyrus. Mice in the running-only group ran, on average, equivalent distances as animals in the running plus enrichment group. The combination of enrichment and running did not significantly increase hippocampal neurogenesis any more than running alone did. Animals in the running-only condition were the only group to show enhanced acquisition on water maze relative to standard cage controls. We confirm and extend the conclusion that environmental enrichment alone does not significantly increase hippocampal neurogenesis or bestow spatial learning benefits in male C57BL/6J mice, even when the modalities of enrichment are very broad.

Growth and food sources of Pacific oyster Crassostrea gigas integrated culture with Sea bass Lateolabrax japonicus in Ailian Bay, China

Shell length and tissue growth of Pacific oyster Crassostrea gigas integrated culture with Sea bass Lateolabrax japonicus were monitored during April–October 2010 in Ailian Bay, China. And also, the food sources of the oyster were analyzed and quantified by stable carbon and nitrogen isotope methods. Results showed that the increment of shell length and flesh dry weight of oyster cultured at cage area were greater than that at control area significantly (P < 0.05). Enrichment of δ13C and δ15N in oyster tissue at the cage area relative to the control area was significant (P < 0.05). Based on the simple linear mixing model, the contribution rate of the fish feces and waste fish feed to oyster was 29.27 and 5.59 %, respectively. This work demonstrates that the differences in growth performance of oyster between cage area and control area were resulted from the utilization of organic matter derived from fish aquaculture. Integrated filter-feeding bivalves culture with marine fish can reduce the environmental impact of organic waste from fish-farming activities.

Prenatal exposure to radiofrequencies: Effects of WiFi signals on thymocyte development and peripheral T cell compartment in an animal model

Wireless local area networks are an increasing alternative to wired data networks in workplaces, homes, and public areas. Concerns about possible health effects of this type of signal, especially when exposure occurs early in life, have been raised. We examined the effects of prenatal (in utero) exposure to wireless fidelity (WiFi) signal-associated electromagnetic fields (2450 MHz center-frequency band) on T cell development and function. Pregnant mice were exposed whole body to a specific absorption rate of 4 W/kg, 2 h per day, starting 5 days after mating and ending 1 day before the expected delivery. Sham-exposed and cage control groups were used as controls. No effects on cell count, phenotype, and proliferation of thymocytes were observed. Also, spleen cell count, CD4/CD8 cell frequencies, T cell proliferation, and cytokine production were not affected by the exposure. These findings were consistently observed in the male and female offspring at early (5 weeks of age) and late (26 weeks of age) time points. Nevertheless, the expected differences associated with aging and/or gender were confirmed. In conclusion, our results do not support the hypothesis that the exposure to WiFi signals during prenatal life results in detrimental effects on the immune T cell compartment.

Controlling and sampling adult sand flies with a fumigant containing permethrin and deltamethrin

The efficacy of a new smoke-generating formulation (fumigant, MidMos Solutions Ltd., GB), containing the active ingredients permethrin and deltamethrin, was evaluated against adult sand flies in an apartment (280 m(3)), a semi-open large animal shelter (enclosing an area of 300 m(2)), a closed Bedouin animal tent (104 m(3)), and a garden (141 m(2)) enclosed by a stone wall. In each location, four cages with approx. 100 Phlebotomus papatasi were exposed to the fumigant 0.5 m and 2.0 m above ground for 15 and 60 min. Controls were kept in untreated similar rooms and there were two repetitions. In the apartment and the animal tent, a single cartridge caused 100% mortality within 15 min. In the large animal shelter, one fumigant caused mortality of 86% in the lower cages and 75% in the upper cages after 15 min. After 60 min, mortality was 94 and 87%, respectively. With two fumigants, mortality was 98.5 and 91% after 15 min and after 60 min all sand flies were dead. In the garden, one fumigant caused mortality of 93% in the lower cages and 85.5% in the upper cages after 15 min. After 60 min the mortality was 98 and 92%, respectively. With two fumigants, all flies were dead within 15 min.

Adhesion of Ligament Periodontal Cells to Different Titanium Surfaces: An In Vitro Comparative Study

Purpose: the present study aims to evaluate, through experiments in vitro, the adhesion capacity of rats periodontal ligament cells on polishing and treated by ionic nitriding (plasma) titanium surfaces. Method: degree II titanium discs (ASTM F86), 15mm of diameter for 1,5mm of thickness, which had received different treatments from surface in 2 distinct groups (polished and cathodic cage plasma nitriding) were used. The cells were isolated from periodontal ligament of rats and cultivated in α-MEM contend antibiotic and supplemented with 10% of FBS, for 72 hours, in humid atmosphere with 5% of CO2 at 37oC. In the subculture the cells were cultivated on titanium discs in 24-well cell culture plates, with a density of 1 x 104 cells per well, including wells with no discs (control). After 24 hours of cultivation, the cells were counted in a Neubauer chamber. Results: the results had shown that the mean adhesion was greater on the control surface (0.62±0.22) than on polished (0.46±0.14) and nitriding (0.33±0.10) surfaces. Statistical significant difference was observed between the groups control and cathodic cage plasma nitriding (p=0.04), nevertheless no diference was found between polished and nitriding groups. Conclusion: the adhesion capacity of rat periodontal ligament cells on the titanium surfaces was not influenced by the different surface treatments given to the material, since none of these contributed positively in the process of cellular adhesion.

ELEVATED tph2 mRNA EXPRESSION IN A RAT MODEL OF CHRONIC ANXIETY

Allelic variations in TPH2, the gene encoding tryptophan hydroxylase 2, the rate-limiting enzyme for brain serotonin (5-HT) biosynthesis, may be genetic predictors of panic disorder and panic responses to panicogenic challenges in healthy volunteers. To test the hypothesis that tph2 mRNA is altered in chronic anxiety states, we measured tph2 expression in an established rat model of panic disorder. We implanted 16 adult, male rats with bilateral guide cannulae and then primed them with daily injections of the corticotropin-releasing factor (CRF) receptor agonist, urocortin 1 (UCN1, 6 fmoles/100 nl per side, n = 8) or vehicle (n = 8) into the basolateral amygdaloid complex (BL) for 5 consecutive days. Anxiety-like behavior was assessed, 24 hr prior to and 48 hr following priming, in the social interaction (SI) test. A third group (n = 7) served as undisturbed home cage controls. All rats were killed 3 days after the last intra-BL injection to analyze tph2 and slc6a4 (gene encoding the serotonin transporter, SERT) mRNA expression in the dorsal raphe nucleus (DR), the main source of serotonergic projections to anxiety-related brain regions, using in situ hybridization histochemistry. UCN1 priming increased anxiety-related behavior in the SI test compared to vehicle-injected controls and elevated tph2, but not slc6a4, mRNA expression in DR subregions, including the ventrolateral DR/ventrolateral periaqueductal gray (DRVL/VLPAG), a subregion previously implicated in control of panic-related physiologic responses. Tph2 mRNA expression in the DRVL/VLPAG was correlated with increased anxiety-related behavior. Our data support the hypothesis that chronic anxiety states are associated with dysregulated tph2 expression.

Early Postnatal Hyperalimentation Impairs Renal Function via SOCS-3 Mediated Renal Postreceptor Leptin Resistance

Early postnatal hyperalimentation has long-term implications for obesity and developing renal disease. Suppressor of cytokine signaling (SOCS) 3 inhibits phosphorylation of signal transducer and activator of transcription (STAT) 3 and ERK1/2 and thereby plays a pivotal role in mediating leptin resistance. In addition, SOCS-3 is induced by both leptin and inflammatory cytokines. However, little is known about the intrinsic-renal leptin synthesis and function. Therefore, this study aimed to elucidate the implications of early postnatal hyperalimentation on renal function and on the intrinsic-renal leptin signaling. Early postnatal hyperalimentation in Wistar rats during lactation was induced by litter size reduction at birth (LSR) either to LSR10 or LSR6, compared with home cage control male rats. Assessment of renal function at postnatal day 70 revealed decreased glomerular filtration rate and proteinuria after LSR6. In line with this impairment of renal function, renal inflammation and expression as well as deposition of extracellular matrix molecules, such as collagen I, were increased. Furthermore, renal expression of leptin and IL-6 was up-regulated subsequent to LSR6. Interestingly, the phosphorylation of Stat3 and ERK1/2 in the kidney, however, was decreased after LSR6, indicating postreceptor leptin resistance. In accordance, neuropeptide Y (NPY) gene expression was down-regulated; moreover, SOCS-3 protein expression, a mediator of postreceptor leptin resistance, was strongly elevated and colocalized with NPY. Thus, our findings not only demonstrate impaired renal function and profibrotic processes but also provide compelling evidence of a SOCS-3-mediated intrinsic renal leptin resistance and concomitant up-regulated NPY expression as an underlying mechanism.

Behavioural state differentially engages septohippocampal cholinergic and GABAergic neurons in R6/1 Huntington’s disease mice

Huntington’s disease (HD) is a neurodegenerative condition characterised by progressive motor, psychological and cognitive decline. R6/1 HD transgenic mice model the clinical hippocampal-dependent cognitive deficits observed in patients. Cholinergic and GABAergic septohippocampal projections play important roles in hippocampal-dependent cognition. The current study examined neuronal activity of cholinergic and GABAergic septohippocampal projections in response to arousal elicited during differing behavioural states. The different behavioural states examined were; home cage (controls), acute exploration of a novel enriched environment and either spontaneous wakefulness (dark phase) or spontaneous sleep (light phase). We employed triple-label immunohistochemistry using c-Fos as an indirect marker of neuron activation and parvalbumin and choline acetyltransferase (ChAT) to label GABAergic and cholinergic neurons in the basal forebrain, respectively. The Y-maze was used to assess short-term hippocampal-dependent memory independently during either the dark or light phase and revealed a memory deficit in R6/1 HD mice compared to wildtypes that was particularly prominent during the dark phase. Three-way ANOVA of basal forebrain cholinergic and GABAergic activity through co-expression of c-Fos revealed overt responses to differing behavioural states. Both genotypes increased cholinergic neuron activity in response to exploring a novel enriched environment and also an increase during the dark phase compared to the light phase. Novel enriched environment exploration caused a larger response of GABAergic neuron activity in R6/1 HD mice, which also failed to increase the activity of GABAergic neurons during the dark phase compared to the light phase as observed for wildtype mice. Basal levels of c-Fos-positive cells were greatly increased in the hippocampal granule cell layer of R6/1 HD mice during both circadian phases. The differential activation of septohippocampal cholinergic and GABAergic neurons in R6/1 HD mice in response to differing behavioural states may be associated with impaired hippocampal-dependent short-term memory.

In utero and early‐life exposure of rats to a Wi‐Fi signal: Screening of immune markers in sera and gestational outcome

An experimental approach was used to assess immunological biomarkers in the sera of young rats exposed in utero and postnatal to non-ionizing radiofrequency fields. Pregnant rats were exposed free-running, 2 h/day and 5 days/week to a 2.45 GHz Wi-Fi signal in a reverberation chamber at whole-body specific absorption rates (SAR) of 0, 0.08, 0.4, and 4 W/kg (with 10, 10, 12, and 9 rats, respectively), while cage control rats were kept in the animal facility (11 rats). Dams were exposed from days 6 to 21 of gestation and then three newborns per litter were further exposed from birth to day 35 postnatal. On day 35 after birth, all pups were sacrificed and sera collected. The screening of sera for antibodies directed against 15 different antigens related to damage and/or pathological markers was conducted using enzyme-linked immunosorbent assay (ELISA). No change in humoral response of young pups was observed, regardless of the types of biomarker and SAR levels. This study also provided some data on gestational outcome following in utero exposure to Wi-Fi signals. Mass evaluation of dams and pups and the number of pups per litter was monitored, and the genital tracts of young rats were observed for abnormalities by measuring anogenital distance. Under these experimental conditions, our observations suggest a lack of adverse effects of Wi-Fi exposure on delivery and general condition of the animals.

Effect of Insect Herbivory on the Architecture and Seed Production of Canola, Brassica napus L.

Abstract Several native Lygus spp. (Hemiptera: Miridae) feed on buds, flowers and immature seeds of canola. These plant resources are also exploited by a recent alien pest now established in southern Alberta, Canada: the cabbage seedpod weevil, Ceutorhynchus obstrictus (Marsham) (Coleoptera: Curculionidae). A caged study was conducted with Brassica napus L. in 2000 and 2002 to determine if various combinations and densities of lygus and seedpod weevils (0, 10 + 10, 20 of either, 20 + 20, 40 + 40, individuals per cage) affected yield and its components such as number of branches, pods and seed weight. Under severely dry conditions, cages with the intermediate (20 + 20) and high (40 + 40) insect combinations had lower grain yield as well as number of racemes and pods per raceme relative to control cages with no insects added. Under more humid conditions in 2002, similar results were observed but the damage by the cabbage seedpod weevil at 20 adults per cage was more apparent than in 2000. These results sugg...

Prior stress interferes with the anxiolytic effect of exercise in c57bl/6j mice.

Recent reports demonstrate that the beneficial effects of voluntary exercise may be sensitive to stress prior to and during the wheel access period. Here, a variate stress procedure is used with socially isolated mice for 7 days prior to the introduction of running wheels to assess the impact of prior and concurrent stress on the anxiolytic effect of exercise. Following stress exposure, functioning or nonfunctioning running wheels were introduced into stressed and unstressed group-housed control cages. Following 3 weeks of wheel access, the anxiolytic effect of exercise was assessed using acoustic startle, stress-induced hyperthermia, and a challenge with the anxiogenic drug metachlorophenylpiperazine (mCPP). Variate stress was demonstrated to interfere with normal weight gain. Further, exercise was not anxiolytic in stressed mice. Consistent with previous reports unstressed exercising mice demonstrated reduced acoustic startle, attenuated stress induced hyperthermia, and a blunted increase in startle following mCPP administration when compared with unstressed sedentary controls. Stressed exercising mice were indistinguishable from stressed sedentary and unstressed sedentary controls on each anxiety measure. Although running distance varied between individual mice, the distance run did not predict the level of anxiety on any measure. These findings suggest that prior and ongoing stress delays or prevents the anxiolytic effect of exercise without affecting exercise itself.

Simulated resistance training, but not alendronate, increases cortical bone formation and suppresses sclerostin during disuse

Mechanical loading modulates the osteocyte-derived protein sclerostin, a potent inhibitor of bone formation. We hypothesized that simulated resistance training (SRT), combined with alendronate (ALEN) treatment, during hindlimb unloading (HU) would most effectively mitigate disuse-induced decrements in cortical bone geometry and formation rate (BFR). Sixty male, Sprague-Dawley rats (6-mo-old) were randomly assigned to either cage control (CC), HU, HU plus either ALEN (HU+ALEN), or SRT (HU+SRT), or combined ALEN and SRT (HU+SRT/ALEN) for 28 days. Computed tomography scans on days -1 and 28 were taken at the middiaphyseal tibia. HU+SRT and HU+SRT/ALEN rats were subjected to muscle contractions once every 3 days during HU (4 sets of 5 repetitions; 1,000 ms isometric + 1,000 ms eccentric). The HU+ALEN and HU+SRT/ALEN rats received 10 μg/kg ALEN 3 times/wk. Compared with the CC animals, HU suppressed the normal slow growth-induced increases of cortical bone mineral content, cortical bone area, and polar cross-sectional moment of inertia; however, SRT during HU restored cortical bone growth. HU suppressed middiaphyseal tibia periosteal BFR by 56% vs. CC (P < 0.05). However, SRT during HU restored BFR at both periosteal (to 2.6-fold higher than CC) and endocortical (14-fold higher than CC) surfaces (P < 0.01). ALEN attenuated the SRT-induced BFR gains during HU. The proportion of sclerostin-positive osteocytes in cortical bone was significantly higher (+121% vs. CC) in the HU group; SRT during HU effectively suppressed the higher proportion of sclerostin-positive osteocytes. In conclusion, a minimum number of high-intensity muscle contractions, performed during disuse, restores cortical BFR and suppress unloading-induced increases in sclerostin-positive osteocytes.

Differential brain-derived neurotrophic factor expression in limbic brain regions following social defeat or territorial aggression.

Syrian hamsters readily form dominant-subordinate relationships under laboratory conditions. Winning or losing in agonistic encounters can have striking, long-term effects on social behavior, but the mechanisms underlying this experience-induced behavioral plasticity are unclear. The present study tested the hypothesis that changes in brain-derived neurotrophic factor (BDNF) may at least in part mediate this plasticity. Male hamsters were paired for 15-min using a resident-intruder model, and individuals were identified as winners or losers on the basis of their behavior. BDNF was examined with in situ hybridization 2 hr after treatment during the consolidation period of emotional learning. Losing animals had significantly more BDNF mRNA in the basolateral (BLA) and medial (MeA) nuclei of the amygdala when compared with winning animals as well as novel cage and home cage controls. Interestingly, winning animals had significantly more BDNF mRNA in the dentate gyrus of the dorsal hippocampus than did losing animals, novel, and home cage controls. No conflict-related changes in BDNF mRNA were observed in several other regions including the bed nucleus of the stria terminalis and central amygdala. Next, we demonstrated that K252a, a Trk receptor antagonist, significantly reduced the acquisition of conditioned defeat when administered within the BLA. These data support a model in which BDNF-mediated plasticity within the BLA supports learning of submission or subordinate social status in losing animals, whereas BDNF-mediated plasticity within the hippocampus may instantiate aspects of winning such as control of a territory in dominant animals.

The effect of exercise on IL‐6‐induced cachexia in the ApcMin/+ mouse

BackgroundCachexia involves unintentional body weight loss including diminished muscle and adipose tissue mass and is associated with an underlying disease. Systemic overexpression of IL-6 accelerates cachexia in the ApcMin/+ mouse, but does not induce wasting in control C57BL/6 mice. With many chronic diseases, chronic inflammation and metabolic dysfunction can be improved with moderate exercise. A direct effect of regular moderate exercise on the prevention of IL-6-induced cachexia in the ApcMin/+ mouse has not been investigated. The purpose of this study was to assess the effects of exercise on the development of cachexia in the ApcMin/+ mouse.MethodsMice were randomly assigned to moderate treadmill exercise (18 m/min, 1 h, 6 days/week, 5% grade) or cage control (CC) groups from 6 to 14 weeks of age. At 12 weeks of age, mice were electroporated with either IL-6-containing or control plasmid into the quadriceps muscle. Mice were killed after 2 weeks of systemic IL-6 overexpression or control treatment.ResultsIL-6 overexpression induced an 8% loss in body weight in CC mice, which was significantly attenuated by exercise. IL-6 overexpression in CC mice increased fasting insulin and triglyceride levels, which were normalized by exercise, and associated with increased oxidative capacity, an induction of AKT signaling, and a repression of AMPK signaling in muscle. These exercise-induced changes occurred despite elevated inflammatory signaling in skeletal muscle.ConclusionWe conclude that moderate-intensity exercise can attenuate IL-6-dependent cachexia in ApcMin/+ mice, independent of changes in IL-6 concentration and muscle inflammatory signaling. The exercise effect was associated with improved insulin sensitivity and improved energy status in the muscle.

Laval mortality of Protaetia brevitarsis in accordance with the different incubation conditions

This study was carried out to determine whether different incubation conditions can affect the larval mortality of Protaetia brevitarsis. In addition, it was carried out to obtain information about the oviposition pattern of P. brevitarsis.P. brevitarsis that was used it the study was a new‐born adult. Adults rearing condition was as follows; temperature 25°C∼27°C, long‐day length (16L:8D), and relative humidity 80%. Larvae were reared at 25°C∼27°C temperature and 80% relative humidity.A total of four types of incubation conditions was designed. First type is the 50 eggs arranged at regular intervals on sawdust (E1). Second type is the 50 eggs put together in the center (E2). Third type is the shift out sawdust and put out adults of P. brevitarsis then put a new cage (E3). Last, lured with bait and put out adults, then put in a new cage (Control). Two weeks later, cages were checked for larval mortality. All of the cages were checked once a week.Types of collect egg are 3. First, don't collect eggs, just lured adults with bait (Control). Second, collect eggs (R1). Last, sift out adults using sieve (R3). Control and R3 eggs remained in cage. Just R1 eggs were arranged on sawdust in new cage.In this study, just Control 1. (10 times repeat) was finished. And other experimental sets are being carried out. In Control 1., larval mortality is 87%. Adults laid 2597 eggs, total 2259 larvae metamorphosed to pupae.Oviposition pattern is Control 1. (10 times repeat) adults laid 3909 eggs, Control 2. (5 times repeat) adults laid 2257 eggs, R1 (10 times repeat) adults laid 3367 eggs, R2 (5 times repeat) adults laid 2142 eggs. Control 1. is preliminary experiment. So, after finish that experiment, repeat that one more time.Usually, P. brevitarsis laid eggs for approximately 10 weeks. And between 2 to 4 weeks, they laid most eggs.

Increased food intake and changes in metabolic hormones in response to chronic sleep restriction alternated with short periods of sleep allowance

Rodent models for sleep restriction have good face validity when examining food intake and related regulatory metabolic hormones. However, in contrast to epidemiological studies in which sleep restriction is associated with body weight gain, sleep-restricted rats show a decrease in body weight. This difference with the human situation might be caused by the alternation between periods of sleep restriction and sleep allowance that often occur in real life. Therefore, we assessed the metabolic consequences of a chronic sleep restriction protocol that modeled working weeks with restricted sleep time alternated by weekends with sleep allowance. We hypothesized that this protocol could lead to body weight gain. Male Wistar rats were divided into three groups: sleep restriction (SR), forced activity control (FA), and home cage control (HC). SR rats were subjected to chronic sleep restriction by keeping them awake for 20 h per day in slowly rotating drums. To model the human condition, rats were subjected to a 4-wk protocol, with each week consisting of a 5-day period of sleep restriction followed by a 2-day period of sleep allowance. During the first experimental week, SR caused a clear attenuation of growth. In subsequent weeks, two important processes occurred: 1) a remarkable increase in food intake during SR days, 2) an increase in weight gain during the weekends of sleep allowance, even though food intake during those days was comparable to controls. In conclusion, our data revealed that the alternation between periods of sleep restriction and sleep allowance leads to complex changes in food intake and body weight, that prevent the weight loss normally seen in continuous sleep-restricted rats. Therefore, this "week-weekend" protocol may be a better model to study the metabolic consequences of restricted sleep.