Pubertal exposure to estrogenic chemicals affects behavior in juvenile and adult male rats

In this paper, we tested the hypothesis that exposure to estrogens of different source and estrogenic potency at early puberty could affect the development of socio-sexual behavior in the male rat. Puberty is regarded as a second stage of the ontogenetic period, in the sexual maturation of mammals, particularly sensitive to gonadal hormone milieu. We treated animals orally, from postnatal day 23 to 30, with an environmentally compatible dose of bisphenol A (BPA, 40 microg/kg/day) and with a dosage of ethinylestradiol (EE, 0.4 microg/kg/day) comparable to the human oral contraceptives. Exposure to EE altered the temporal pattern of male sexual activity, reducing performance, in the adult animals; slight modifications, in the same direction, were observed with BPA. Short-term behavioral effects were observed in the treated animals, both with BPA and EE: the exploratory drive, directed to a stimulus object and to the environment, as well as to conspecifics, was reduced in the juveniles. Modifications in the circulating T levels were observed after treatments: T was reduced in the juveniles, both with BPA and EE. The decrement persisted in the adult animals but reached significance only in the BPA group. On the whole, effects of pubertal exposure on behavior are more marked with EE than BPA. This can be due to the much higher estrogenic potency of EE; the direction of the behavioral effects of BPA, compared with EE, is however indicative of an estrogenic mechanism.     

Responses to Environmental Enrichment Differ with Sex and Genotype in a Transgenic Mouse Model of Huntington's Disease

Background

Environmental enrichment (EE) in laboratory animals improves neurological function and motor/cognitive performance, and is proposed as a strategy for treating neurodegenerative diseases. EE has been investigated in the R6/2 mouse model of Huntington''s disease (HD), where increased social interaction, sensory stimulation, exploration, and physical activity improved survival. We have also shown previously that HD patients and R6/2 mice have disrupted circadian rhythms, treatment of which may improve cognition, general health, and survival.

Methodology/Principal Findings

We examined the effects of EE on the behavioral phenotype and circadian activity of R6/2 mice. Our mice are typically housed in an “enriched” environment, so the EE that the mice received was in addition to these enhanced housing conditions. Mice were either kept in their home cages or exposed daily to the EE (a large playground box containing running wheels and other toys). The “home cage” and “playground” groups were subdivided into “handling” (stimulated throughout the experimental period) and “no-handling” groups. All mice were assessed for survival, body weight, and cognitive performance in the Morris water maze (MWM). Mice in the playground groups were more active throughout the enrichment period than home cage mice. Furthermore, R6/2 mice in the EE/no-handling groups had better survival than those in the home cage/no-handling groups. Sex differences were seen in response to EE. Handling was detrimental to R6/2 female mice, but EE increased the body weight of male R6/2 and WT mice in the handling group. EE combined with handling significantly improved MWM performance in female, but not male, R6/2 mice.

Conclusions/Significance

We show that even when mice are living in an enriched home cage, further EE had beneficial effects. However, the improvements in cognition and survival vary with sex and genotype. These results indicate that EE may improve the quality of life of HD patients, but we suggest that EE as a therapy should be tailored to individuals.     

Molecular simulation on the interaction of Ethinylestradiol (EE2) with polymer membranes in wastewater purification

Molecular dynamics (MD) simulations are performed to study the adsorption of solute organic molecules (Ethinylestradiol (EE2) and testosterone) with different polymer membranes such as polyether sulfone (PES), polyvinylidene fluoride (PVDF). The equilibrium MD simulations results for the membrane solution interface system show that the interaction of EE2 with PES is specific and strong, whereas the interaction is weak and non-specific for PVDF. The binding free energies, the non-bonded short range interaction energies and mobility are also consistent with the interaction behaviour found in experiments. The adsorption of testosterone onto PES and PVDF is considered as control system. The result shows that binding free energies of PES and PVDF interacting with organic solute are consistent with experimental result in the order as; PES-EE2 > PES-Testosterone > PVDF-EE2 > PVDF-Testosterone. The formation hydrogen bonds and π–π interactions are observed between the EE2 and PES. In addition, adsorption of EE2 onto polyamide 6-12 (PA612) and polystyrene (PS) membranes are predicted. This simulation study provides molecular insights on the experimental observations and helps as a computational methodology to screen the membrane materials for EE2 removal from wastewater.     

Evaluation of low-intensity physical activity by triaxial accelerometry

Objective: To develop regression‐based equations that estimate physical activity ratios [energy expenditure (EE) per minute/sleeping metabolic rate] for low‐to‐moderate intensity activities using total acceleration obtained by triaxial accelerometry. Research Methods and Procedures: Twenty‐one Japanese adults were fitted with a triaxial accelerometer while also in a whole‐body human calorimeter for 22.5 hours. The protocol time was composed of sleep (8 hours), four structured activity periods totaling 4 hours (sitting, standing, housework, and walking on a treadmill at speeds of 71 and 95 m/min, 2 × 30 minutes for each activity), and residual time (10.5 hours). Acceleration data (milligausse) from the different periods and their relationship to physical activity ratio obtained from the human calorimeter allowed for the development of EE equations for each activity. The EE equations were validated on the residual times, and the percentage difference for the prediction errors was calculated as (predicted value ? measured value)/measured value × 100. Results: Using data from triaxial accelerations and the ratio of horizontal to vertical accelerations, there was relatively high accuracy in identifying the four different periods of activity. The predicted EE (882 ± 150 kcal/10.5 hours) was strongly correlated with the actual EE measured by human calorimetry (846 ± 146 kcal/10.5 hours, r = 0.94 p < 0.01), although the predicted EE was slightly higher than the measured EE. Discussion: Triaxial accelerometry, when total, vertical, and horizontal accelerations are utilized, can effectively evaluate different types of activities and estimate EE for low‐intensity physical activities associated with modern lifestyles.     

Short-Term Exposure to Enriched Environment in Adult Rats Restores MK-801-Induced Cognitive Deficits and GABAergic Interneuron Immunoreactivity Loss

Perinatal injections of N-methyl-D-aspartate (NMDA) receptor antagonist in rodents emulate some cognitive impairments and neurochemical alterations, such as decreased GABAergic (gamma aminobutyric acid) interneuron immunoreactivity, also found in schizophrenia. These features are pervasive, and developing neuroprotective or neurorestorative strategies is of special interest. In this work, we aimed to investigate if a short exposure to enriched environment (EE) in early adulthood (P55–P73) was an effective strategy to improve cognitive dysfunction and to restore interneuron expression in medial prefrontal cortex (mPFC) and hippocampus (HPC). For that purpose, we administered MK-801 intraperitoneally to Long Evans rats from postnatal days 10 to 20. Twenty-four hours after the last injection, MK-801 produced a transient decrease in spontaneous motor activity and exploration, but those abnormalities were absent at P24 and P55. The open field test on P73 manifested that EE reduced anxiety-like behavior. In addition, MK-801-treated rats showed cognitive impairment in novel object recognition test that was reversed by EE. We quantified different interneuron populations based on their calcium-binding protein expression (parvalbumin, calretinin, and calbindin), glutamic acid decarboxylase 67, and neuronal nuclei-positive cells by means of unbiased stereology and found that EE enhanced interneuron immunoreactivity up to normal values in MK-801-treated rats. Our results demonstrate that a timely intervention with EE is a powerful tool to reverse long-lasting changes in cognition and neurochemical markers of interneurons in an animal model of schizophrenia.     

Nest Making and Oxytocin Comparably Promote Wound Healing in Isolation Reared Rats

Background

Environmental enrichment (EE) fosters attachment behavior through its effect on brain oxytocin levels in the hippocampus and other brain regions, which in turn modulate the hypothalamic-pituitary axis (HPA). Social isolation and other stressors negatively impact physical healing through their effect on the HPA. Therefore, we reasoned that: 1) provision of a rat EE (nest building with Nestlets®) would improve wound healing in rats undergoing stress due to isolation rearing and 2) that oxytocin would have a similar beneficial effect on wound healing.

Methodology/Principal Findings

In the first two experiments, we provided isolation reared rats with either EE or oxytocin and compared their wound healing to group reared rats and isolation reared rats that did not receive Nestlets or oxytocin. In the third experiment, we examined the effect of Nestlets on open field locomotion and immediate early gene (IEG) expression. We found that isolation reared rats treated with Nestlets a) healed significantly better than without Nestlets, 2) healed at a similar rate to rats treated with oxytocin, 3) had decreased hyperactivity in the open field test, and 4) had normalized IEG expression in brain hippocampus.

Conclusions/Significance

This study shows that when an EE strategy or oxytocin is given to isolation reared rats, the peripheral stress response, as measured by burn injury healing, is decreased. The findings indicate an association between the effect of nest making on wound healing and administration of the pro-bonding hormone oxytocin. Further elucidation of this animal model should lead to improved understanding of how EE strategies can ameliorate poor wound healing and other symptoms that result from isolation stress.     

Rethinking the role of theory in exploratory experimentation

To explain their role in discovery and contrast them with theory-driven research, philosophers of science have characterized exploratory experiments in terms of what they lack: namely, that they lack direction from what have been called “local theories” of the target system or object under investigation. I argue that this is incorrect: it’s not whether or not there is direction from a local theory that matters, but instead how such a theory is used to direct an experiment that matters. Appealing to contemporary exploratory experiments that involve the use of experimental techniques—specifically, examples where scientists explore the interaction of neural activity and human behavior by magnetically stimulating brains—I argue that local theories of a target system can inform auxiliary hypotheses in exploratory experiments, which direct these experiments. These examples illustrate how local theories can direct the exploration of target systems where researchers do not aim to evaluate these theories.     

MOtoNMS: A MATLAB toolbox to process motion data for neuromusculoskeletal modeling and simulation

Background

Neuromusculoskeletal modeling and simulation enable investigation of the neuromusculoskeletal system and its role in human movement dynamics. These methods are progressively introduced into daily clinical practice. However, a major factor limiting this translation is the lack of robust tools for the pre-processing of experimental movement data for their use in neuromusculoskeletal modeling software.

Results

This paper presents MOtoNMS (matlab MOtion data elaboration TOolbox for NeuroMusculoSkeletal applications), a toolbox freely available to the community, that aims to fill this lack. MOtoNMS processes experimental data from different motion analysis devices and generates input data for neuromusculoskeletal modeling and simulation software, such as OpenSim and CEINMS (Calibrated EMG-Informed NMS Modelling Toolbox). MOtoNMS implements commonly required processing steps and its generic architecture simplifies the integration of new user-defined processing components. MOtoNMS allows users to setup their laboratory configurations and processing procedures through user-friendly graphical interfaces, without requiring advanced computer skills. Finally, configuration choices can be stored enabling the full reproduction of the processing steps. MOtoNMS is released under GNU General Public License and it is available at the SimTK website and from the GitHub repository. Motion data collected at four institutions demonstrate that, despite differences in laboratory instrumentation and procedures, MOtoNMS succeeds in processing data and producing consistent inputs for OpenSim and CEINMS.

Conclusions

MOtoNMS fills the gap between motion analysis and neuromusculoskeletal modeling and simulation. Its support to several devices, a complete implementation of the pre-processing procedures, its simple extensibility, the available user interfaces, and its free availability can boost the translation of neuromusculoskeletal methods in daily and clinical practice.

     

Estrogen effect on post-exercise skeletal muscle neutrophil infiltration and calpain activity

We hypothesized that estrogen administration would attenuate skeletal muscle neutrophil infiltration, indices of muscle membrane disruption, and muscle calpain activity shortly after the termination of exercise. Ovariectomized female rats were implanted with either an estogen pellet (25 mg beta-estradiol) or a placebo pellet. Two weeks postimplant, animals were killed either at rest or 1 h after running exercise (60 min at 21 m x min(-1), 12% grade). The 4 experimental groups (n = 12) used were: unexercised placebo (UP), unexercised estrogen (UE), exercised placebo (EP), and exercised estrogen (EE). Blood samples were analyzed for creatine kinase (CK) activity and estradiol content. Plantaris and gastrocnemius muscles were removed and histochemical determination of neutrophil content or biochemical determination of myeloperoxidase (MPO), glucose-6-phosphate dehydrogenase (G6PD), and calpain-like activity determined. Estrogen supplemented animals had 10-20-fold higher circulating estradiol levels than placebo animals. EP animals had significantly higher (P < 0.05) circulating CK activities than EE or unexercised animals. Muscle neutrophil concentrations were significantly (P < 0.01) elevated in EP and EE groups compared with unexercised controls, with EP muscle neutrophil levels also being over 60% greater (P < 0.05) than in EE animals. EP animals also had higher (P < 0.05) muscle MPO activities than unexercised or EE animals. Muscle G6PD activities were not significantly different between any groups. Muscle caplain-like activities were 80% higher (P < 0.01) in EP animals than EE animals with calpain-like activities in EE animals similar to unexercised groups. These results indicate that estrogen supplementation in ovariectomized rats attenuated 1-h post-exercise serum CK activities, muscle neutrophil infiltration, MPO activities, and calpain-like activities when compared with exercised, unsupplemented animals. This supports the possibility of a relationship between estrogen, calpain dependent production of neutrophil chemo-attractant peptides, and 1-h post-exercise skeletal muscle neutrophil infiltration.     

Development and Validation of a Measurement System for Assessment of Energy Expenditure and Physical Activity in Prader-Willi Syndrome

CHEN, KONG Y., MING SUN, MERLIN G. BUTLER, TRAVIS THOMPSON, AND MICHAEL G. CARLSON. Development and validation of a measurement system for assessment of energy expenditure and physical activity in Prader—Willi syndrome. Obes Res. Objective: The morbid obesity associated with Prader—Willi syndrome (PWS) may result from either excessive energy intake or reduced energy expenditure (EE). In this report, we describe the development and validation of an Activity—Energy Measurement System (AEMS) to measure EE and physical activity components in an environment approximating free-living conditions. Research Methods and Procedures: The AEMS consists of a live-in, whole-room indirect calorimeter equipped with a novel force platform floor system to enable simultaneous measurements of EE, physical activity, and work efficiency during spontaneous activities and standardized exercises. Free-living physical activity and estimated free-living EE are measured using portable triaxial accelerometers individually calibrated in each subject during their stay in the AEMS. Results: Representative data from two PWS patients and two matched control (CTR) subjects displayed EE during their inactive lifestyles. Discussion: This combination of methods will allow the quantification of daily EE and its components, the amount and energy cost of physical activity, and the relationships between body composition and EE, in order to determine their roles in the development and maintenance of the morbid obesity in PWS.     

Triaxial accelerometry for assessment of physical activity in young children

Objective: The purpose of the present study was to derive linear and non‐linear regression equations that estimate energy expenditure (EE) from triaxial accelerometer counts that can be used to quantitate activity in young children. We are unaware of any data regarding the validity of triaxial accelerometry for assessment of physical activity intensity in this age group. Research Methods and Procedures: EE for 27 girls and boys (6.0 ± 0.3 years) was assessed for nine activities (lying down, watching a video while sitting and standing, line drawing for coloring‐in, playing blocks, walking, stair climbing, ball toss, and running) using indirect calorimetry and was then estimated using a triaxial accelerometer (ActivTracer, GMS). Results: Significant correlations were observed between synthetic (synthesized tri‐axes as the vector), vertical, and horizontal accelerometer counts and EE for all activities (0.878 to 0.932 for EE). However, linear and non‐linear regression equations underestimated EE by >30% for stair climbing (up and down) and performing a ball toss. Therefore, linear and non‐linear regression equations were calculated for all activities except these two activities, and then evaluated for all activities. Linear and non‐linear regression equations using combined vertical and horizontal acceleration counts, synthetic counts, and horizontal counts demonstrated a better relationship between accelerometer counts and EE than did regression equations using vertical acceleration counts. Adjustment of the predicted value by the regression equations using the vertical/horizontal counts ratio improved the overestimation of EE for performing a ball toss. Discussion: The results suggest that triaxial accelerometry is a good tool for assessing daily EE in young children.     

Visual Exploratory Search of Relationship Graphs on Smartphones

This paper presents a novel framework for Visual Exploratory Search of Relationship Graphs on Smartphones (VESRGS) that is composed of three major components: inference and representation of semantic relationship graphs on the Web via meta-search, visual exploratory search of relationship graphs through both querying and browsing strategies, and human-computer interactions via the multi-touch interface and mobile Internet on smartphones. In comparison with traditional lookup search methodologies, the proposed VESRGS system is characterized with the following perceived advantages. 1) It infers rich semantic relationships between the querying keywords and other related concepts from large-scale meta-search results from Google, Yahoo! and Bing search engines, and represents semantic relationships via graphs; 2) the exploratory search approach empowers users to naturally and effectively explore, adventure and discover knowledge in a rich information world of interlinked relationship graphs in a personalized fashion; 3) it effectively takes the advantages of smartphones’ user-friendly interfaces and ubiquitous Internet connection and portability. Our extensive experimental results have demonstrated that the VESRGS framework can significantly improve the users’ capability of seeking the most relevant relationship information to their own specific needs. We envision that the VESRGS framework can be a starting point for future exploration of novel, effective search strategies in the mobile Internet era.     

Functional characterization of the microtubule-binding and -destabilizing domains of CPAP and d-SAS-4

We previously identified a novel centrosomal protein CPAP, which carries a 112-residue motif that is essential for microtubule destabilization. In this report, we define both the microtubule (MT) binding and destabilizing domains in human CPAP and analyze the mutations that affect its MT-destabilizing activity. Analysis of a series of CPAP truncated proteins showed that the MT-binding domain (MBD; residues 423–607) of CPAP is located next to its MT-destabilizing domain (MDD; residues 311–422). Site-specific mutagenesis revealed that the mutations that either disrupt the α-helical structure (Y341P, I346P, L348P, and triple-P) or alter the charge property (KR377EE) of the MDD significantly affect its MT-destabilizing ability. The activity for binding to a tubulin heterodimer was also significantly reduced in KR377EE mutant. Furthermore, we have analyzed the putative function of Drosophila d-SAS-4, a distant relative of human CPAP, which shares a conserved  20-aa sequence with the MDD of CPAP. Our results show that mutations in this conserved sequence also eliminate d-SAS-4′s MT-destabilizing activity, suggesting that d-SAS-4 and CPAP may play similar roles within cells.     

Variants of guided self-organization for robot control

Autonomous robots can generate exploratory behavior by self-organization of the sensorimotor loop. We show that the behavioral manifold that is covered in this way can be modified in a goal-dependent way without reducing the self-induced activity of the robot. We present three strategies for guided self-organization, namely by using external rewards, a problem-specific error function, or assumptions about the symmetries of the desired behavior. The strategies are analyzed for two different robots in a physically realistic simulation.     

The relevance of the pharmacologic properties of a progestational agent to its clinical effects as a combination oral contraceptive

Levonorgestrel (LNg) is known for its marked progestational/contraceptive activity. As shown in animal experiments, however, high doses of LNg are required to elicit an androgenic response; in contrast, considerably lower doses of LNg are required for antiovulatory (contraceptive) action. Thus, a large dose separation exists between androgenic and contraceptive activity. When LNg is combined with an estrogen, as in the contraceptive formulations, the androgenic response is attenuated or negated. The results of recent clinical trials have demonstrated that the androgenic activity of LNg is not expressed at contraceptive doses, particularly when LNg is combined with ethinyl estradiol (EE), as in the low-dose monophasic/triphasic formulations (monophasic [Nordette]: 150 mcg LNg/30 mcg EE; triphasic [Triphasil/Trinordiol]: six days, 50 mcg LNg/30 mcg EE; five days, 75 mcg LNg/40 mcg EE; ten days, 125 mcg LNg/30 mcg EE). Clinical evidence from several trials confirms that sex hormone-binding globulin levels are increased, plasma androgen levels are decreased, and acne is markedly improved with the use of Triphasil and Nordette, suggesting a non-androgenic profile.     

Statistical Design for Formulation Optimization of Hydrocortisone Butyrate-Loaded PLGA Nanoparticles

The aim of this investigation was to develop hydrocortisone butyrate (HB)-loaded poly(d,l-lactic-co-glycolic acid) (PLGA) nanoparticles (NP) with ideal encapsulation efficiency (EE), particle size, and drug loading (DL) under emulsion solvent evaporation technique utilizing various experimental statistical design modules. Experimental designs were used to investigate specific effects of independent variables during preparation of HB-loaded PLGA NP and corresponding responses in optimizing the formulation. Plackett–Burman design for independent variables was first conducted to prescreen various formulation and process variables during the development of NP. Selected primary variables were further optimized by central composite design. This process leads to an optimum formulation with desired EE, particle size, and DL. Contour plots and response surface curves display visual diagrammatic relationships between the experimental responses and input variables. The concentration of PLGA, drug, and polyvinyl alcohol and sonication time were the critical factors influencing the responses analyzed. Optimized formulation showed EE of 90.6%, particle size of 164.3 nm, and DL of 64.35%. This study demonstrates that statistical experimental design methodology can optimize the formulation and process variables to achieve favorable responses for HB-loaded NP.     

Environmental education indicators system for protected areas management

A new perspective for the management effectiveness of protected areas needs the inclusion of social data for decision-making. In this process, environmental education (EE) plays a key role in catalyzing biological and social issues in the management process, but there are scarce data about this relationship. The objective of this paper is to develop, from an institutional bottom-up perspective, a proposal for a set of EE indicators that is easy to use by practitioners to measure the response of the EE program in relation to the conservation objectives of protected areas management plans. Using a combination of quantitative and qualitative techniques, a case study at the National Parks System of Colombia is presented, which is divided in five stages: 1. An EE evaluation survey on a national scale. 2. An interview phase with EE practitioners and NGOs. 3. EE objectives categorization. 4. Systematization process and 5. Focus group to evaluate the proposed set of indicators. A set of 5 EE indicators was developed to fulfill the identified needs: appropriation of information, articulation, participation quality, program implementation and continuity of EE process. We expect that this new approach for EE evaluation will hopefully be adopted in the update of management plans, as an innovative tool that contributes to the effectiveness assessment of protected areas, integrating a more social and participative focus.