Pueraria mirifica extract and puerarin enhance proliferation and expression of alkaline phosphatase and type I collagen in primary baboon osteoblasts

Phytoestrogen-rich Pueraria mirifica (PM) tuberous extract is a promising candidate for the development of anti-osteoporosis drugs for postmenopausal women, but its action has never been validated in humans or in non-human primates, which are more closely related to humans than rodents. In vitro study of non-human primate osteoblasts is thus fundamental to prepare for in vivo studies of phytoestrogen effects on primate bone. This study aimed to establish a culture system of baboon primary osteoblasts and to investigate the effects of PM extract and its phytoestrogens on these cells. Primary osteoblasts from adult baboon fibulae exhibited osteoblast characteristics in regard to proliferation, differentiation, mineralization, and estrogen receptor expression. They responded to 17β-estradiol by increased proliferation rate and mRNA levels of alkaline phosphatase (ALP), type I collagen, and osteocalcin. After being exposed for 48 h to 100 μg/ml PM extract, 1000 nM genistein, or 1000 nM puerarin, primary baboon osteoblasts markedly increased the rate of proliferation and mRNA levels of ALP and type I collagen without changes in Runx2, osterix, or osteocalcin expression. PM extract, genistein, and puerarin also decreased the RANKL/OPG ratio, suggesting that they could decrease osteoclast-mediated bone resorption. However, neither PM extract nor its phytoestrogens altered calcium deposition in osteoblast culture. In conclusion, we have established baboon primary osteoblast culture, which is a new tool for bone research and drug discovery. Furthermore, the present results provide substantial support for the potential of PM extract and its phytoestrogens to be developed as therapeutic agents against bone fragility.     

Occurrence of human-pathogenic Enterocytozoon bieneusi,Giardia duodenalis and Cryptosporidium genotypes in laboratory macaques in Guangxi,China

Captive nonhuman primates have been identified as common hosts of Enterocytozoon bieneusi, Giardia duodenalis, Cryptosporidium hominis, and Cyclospora spp., thus are potential reservoirs of some enteric parasites in humans. However, few studies have examined the source and human-infective potential of enteric parasites in laboratory nonhuman primates. In the present work, 205 fecal specimens were collected from three groups of captive Macaca fascicularis kept in different densities in a laboratory animal facility in Guangxi, China, and examined by PCR for E. bieneusi, G. duodenalis, Cryptosporidium spp., and Cyclospora spp. The infection rates of E. bieneusi and G. duodenalis were 11.3% and 1.2% in Group 1 (young animals kept individually; n = 168), 72.2% and 11.1% in Group 2 (young animals kept in groups; n = 18), and 31.6% and 5.3% in Group 3 (adults kept in groups; n = 19), respectively. Sequence analysis of PCR products showed the presence of five E. bieneusi genotypes, with genotype D (in 16/36 genotyped specimens) and a new genotype (in 15/36 genotyped specimens) as the dominant genotypes. All five E. bieneusi genotypes belonged to the zoonotic group (Group 1). The G. duodenalis genotypes (assemblages AII and B) in five specimens and C. hominis subtype (IdA14) in one specimen were also known human-pathogens, although the Cyclospora seen in one animal appeared to be unique to macaque monkeys. The higher infection rate in younger animals reared in groups and common occurrence of zoonotic genotypes indicated that human-pathogenic E. bieneusi could be transmitted efficiently in captive nonhuman primates, and group-housing was a risk factor for transmission of zoonotic pathogens in young nonhuman primates in research facilities.     

Metabolic activation of phenanthrene by human and mouse cytochromes P450 and pharmacokinetics in CYP1A2 knockout mice

In the present study V79 Chinese hamster cells were genetically engineered for stable expression of the cytochromes P450 1A1, 1A2, 1B1, and 2E1 from man and mouse to investigate species-specific differences in the regioselective metabolism and toxicity of phenanthrene (Phe), the simplest polycyclic aromatic hydrocarbon (PAH) forming a bay-region. Phe is present in various environmental samples and serves as a model substrate for PAH exposure in human biomonitoring studies. For this reason we explored metabolite profiles and metabolite-dependent cytotoxic activities in vitro. The total turnover of CYP-mediated transformation of Phe was as follows: human CYP1B1 > CYP1A1 > CYP1A2 ? CYP2E1, and for mouse CYP1A2 ? CYP2E1 > CYP1A1. Striking species differences were seen as mouse CYP1B1 did not activate Phe at all, but human CYP1B1 exhibited a significant metabolic turnover comparable to CYP1A1 and CYP1A2. In vivo studies monitoring the whole blood Phe elimination in CYP1A2 knockout and wild-type mice after oral administration confirmed involvement of CYP1A2 in the bioactivation of Phe, but other processes must contribute also. Our data suggest that in humans not only CYP1A2 expressed solely in the liver plays a crucial role in Phe metabolism, but also constitutively expressed extrahepatic CYP1B1 in tissues such as lung, kidney or intestine. This finding will substantially improve the validity of human biomonitoring studies using individual Phe metabolites for the assessment of PAH exposure.     

Effects of short- and long-term changes in spatial density on the social behavior of captive chimpanzees (Pan troglodytes)

The constraints of captivity may often require non-human primates to experience restrictions in space for both long- and short-term periods of time. The tension-reduction model predicts that great apes should increase affiliative behaviors and decrease aggressive behaviors as a coping strategy. The conflict avoidance model, however, predicts that great apes should decrease all social interactions (affiliative and aggressive) as a coping strategy. The purpose of this study was to test the conflict-avoidance and tension-reduction models by examining the effects of both short-term (1–2 days) and long-term (6 months) changes in spatial density on social behavior in 23 adult captive chimpanzees (6 males, 17 females) housed at the Primate Foundation of Arizona. Affiliative (i.e., social groom, social play) and agonistic (i.e., charging display, attack) were assessed using scan-sampling techniques while subjects were rotated from high-density to low-density conditions for varying lengths of time. Results of short-term increases in spatial density (crowding) supported the conflict-avoidance strategy for females, through reduced levels of aggressive (F_1,16 = 17.11, p = 0.001) and affiliative (F_1,16 = 21.13, p < 0.001) behaviors. Males, however, supported the tension-reduction model during short-term high-density by decreasing aggression (F_1,5 = 10.53, p = 0.02) while increasing affiliation (F_1,5 = 9.10, p = 0.03). Females partially supported the tension-reduction model during long-term high-density by increasing affiliative behaviors (F_1,16 = 14.19, p = 0.002) compared to short-term high-density levels, while rates of aggression remained low. Finally, males supported the tension-reduction by reducing aggression (F_1,5 = 7.668, p = 0.04) and increasing affiliation (F_1,5 = 6.08, p = 0.05) during long-term high-density. Results confirm that chimpanzees use different strategies during short-term versus long-term increases in spatial density and that these strategies may be influenced by individual sex. However, sample sizes are small and additional research on male chimpanzees is needed.     

Discovery of novel α1-adrenoceptor ligands based on the antipsychotic sertindole suitable for labeling as PET ligands

The synthesis and in vitro preclinical profile of a series of 5-heteroaryl substituted analogs of the antipsychotic drug sertindole are presented. Compounds 1-(4-fluorophenyl)-3-(1-methylpiperidin-4-yl)-5-(pyrimidin-5-yl)-1H-indole (Lu AA27122, 3i) and 1-(4-fluorophenyl)-5-(1-methyl-1H-1,2,4-triazol-3-yl)-3-(1-methylpiperidin-4-yl)-1H-indole (3l) were identified as high affinity α_1A-adrenoceptor ligands with K_i values of 0.52 and 0.16 nM, respectively, and with a >100-fold selectivity versus dopamine D₂ receptors. Compound 3i showed almost equal affinity for α_1B- (K_i = 1.9 nM) and α_1D-adrenoceptors (K_i = 2.5 nM) as for α_1A, as well as moderate affinity for 5-HT_1B (K_i = 13 nM) and 5-HT₆ (K_i = 16 nM) receptors, whereas 3l showed >40-fold selectivity toward all other targets tested. Based on in vitro assays for assessment of permeability rates and extent, it is predicted that both compounds enter the brain of rats, non-human primates, as well as humans, and as such are good candidates to be carried forward for further evaluation as positron emission tomography (PET) ligands.     

Opposite changes in cannabinoid CB1 and CB2 receptor expression in human gliomas

Gliomas are the most important group of malignant primary brain tumors and one of the most aggressive forms of cancer. During the last years, several studies have demonstrated that cannabinoids induce apoptosis of glioma cells and inhibit angiogenesis of gliomas in vivo. As the effects of cannabinoids rely on CB₁ and CB₂ receptors activation, the aim of the present study was to investigate both receptors protein expression in cellular membrane homogenates of human glial tumors using specific antibodies raised against these proteins. Additionally, we studied the functionality of the cannabinoid receptors in glioblastomas by using WIN 55,212-2 stimulated [³⁵S]GTPγS binding.Western blot analysis showed that CB₁ receptor immunoreactivity was significantly lower in glioblastoma multiforme (?43%, n = 10; p < 0.05) than in normal post-mortem brain tissue (n = 16). No significant differences were found for astrocytoma (n = 6) and meningioma (n = 8) samples. Conversely, CB₂ receptor immunoreactivity was significantly greater in membranes of glioblastoma multiforme (765%, n = 9; p < 0.05) and astrocytoma (471%, n = 4; p < 0.05) than in control brain tissue (n = 10). Finally, the maximal stimulation of [³⁵S]GTPγS binding by WIN 55,212-2 was significantly lower in glioblastomas (134 ± 4%) than in control membranes (183 ± 2%; p < 0.05). The basal [³⁵S]GTPγS binding and the EC₅₀ values were not significantly different between both groups.The present results demonstrate opposite changes in CB₁ and CB₂ receptor protein expression in human gliomas. These changes may be of interest for further research about the therapeutic effects of cannabinoids in glial tumors.     

Cortical motor representation of the rectus femoris does not differ between the left and right hemisphere

Transcranial magnetic stimulation (TMS) involves non-invasive magnetic stimulation of the brain, and can be used to explore the corticomotor excitability and motor representations of skeletal muscles. However there is a lack of motor mapping studies in the lower limb and few conducted in healthy cohorts. The cortical motor representations of muscles can vary between individuals in terms of center position and area despite having a general localized region within the motor cortex. It is important to characterize the normal range for these variables in healthy cohorts to be able to evaluate changes in clinical populations. TMS was used in this cross-sectional study to assess the active motor threshold (AMT) and cortical representation area for rectus femoris in 15 healthy individuals (11 M/4F 27.3 ± 5.9 years). No differences were found between hemispheres (Left vs. Right P = 0.130) for AMT. In terms of y-axis center position no differences were found between hemispheres (Left vs. Right P = 0.539), or for the x-axis center position (Left vs. Right P = 0.076). Similarly, no differences in calculated area of the motor representation were found (Left vs. Right P = 0.699) indicating symmetry between hemispheres.     

The breeding management affects fresh and cryopreserved semen characteristics in Melopsittacus undulatus

Melopsittacus undulatus is a companion parrot worldwide diffused. Many parrots are considered endangered or vulnerable. The preservation of semen is crucial in endangered species, thus, M. undulatus could be a good model to study sperm characteristics and semen cryopreservation in these other endangered parrots. In this study the effect of the breeding management (males bred in promiscuous aviary or in couple) on sperm characteristics (motility, membrane integrity and morphometry) of fresh and cryopreserved semen was evaluated. The computer-assisted sperm analysis (CASA) revealed a significant effect of the husbandry method on semen characteristics in budgerigars: male housed in couple with the female in individual cages allowed the higher results in term of both semen quantity and sperm quality. Total and progressive motility were significantly higher in males bred in couple (68.7 ± 8.9% and 54 ± 15.9%, respectively) than in promiscuous aviary (48.3 ± 15.1% and 24.4 ± 12.4%, respectively), such as sperm velocity (average path velocity, straight line velocity, and curvilinear velocity). The type of sperm movement (amplitude of lateral head displacement, beat cross frequency, straightness, and linearity), sperm membrane integrity and morphometry parameters seemed not affected by the husbandry method. The standardization of a CASA procedure for the semen analysis in M. undulatus allow further studies on parrot semen manipulation and cryopreservation, but the method used for the breeding of the male could have a significant effect on the semen quality.     

The mouse Gm853 gene encodes a novel enzyme: Leucine decarboxylase

Ornithine decarboxylase (ODC) is a key enzyme in the biosynthesis of polyamines. ODC-antizyme inhibitors (AZINs) are homologous proteins of ODC, devoid of enzymatic activity but acting as regulators of polyamine levels. The last paralogue gene recently incorporated into the ODC/AZINs family is the murine Gm853, which is located in the same chromosome as AZIN2, and whose biochemical function is still unknown. By means of transfection assays of HEK293T cells with a plasmid containing the coding region of Gm853, we show here that unlike ODC, GM853 was a stable protein that was not able to decarboxylate l-ornithine or l-lysine and that did not act as an antizyme inhibitor. However, GM853 showed leucine decarboxylase activity, an enzymatic activity never described in animal cells, and by acting on l-leucine (Km = 7.03 × 10^? 3 M) it produced isopentylamine, an aliphatic monoamine with unknown function. The other physiological branched-chain amino acids, l-valine and l-isoleucine were poor substrates of the enzyme. Gm853 expression was mainly detected in the kidney, and as Odc, it was stimulated by testosterone. The conservation of Gm853 orthologues in different mammalian species, including primates, underlines the possible biological significance of this new enzyme. In this study, we describe for the first time a mammalian enzyme with leucine decarboxylase activity, therefore proposing that the gene Gm853 and its protein product should be named as leucine decarboxylase (Ldc, LDC).     

Effect of microwave irradiation on the structure of glucoamylase

In the present study, we describe changes in the primary and secondary structural patterns of glucoamylase during starch hydrolysis under microwave irradiation using SDS-PAGE and circular dichroism (CD) spectroscopy. Our SDS-PAGE results show that the primary structure of glucoamylase did not change after microwave irradiation. According to the CD spectra, the positive peak height (λ = 193 nm) of the microwave-irradiated samples decreased by 36.4–68.2% compared to those without irradiation, whereas the double negative peak height (λ = 206 nm, λ = 220 nm) increased by 10.8–31.4%. In addition, the positive peak (λ = 193 nm) shifted by 0.2–3 nm. After treatment of glucoamylase with microwave irradiation, the α-helical content of glucoamylase decreased sharply, whereas the β-sheet, β-turn and random coil content increased gradually. The conformational changes of glucoamylase after microwave irradiation provide theoretical support for the mechanism whereby microwave irradiation accelerates starch hydrolysis catalyzed by glucoamylase.     

Antioxidant treatment reduces matrix metalloproteinase-2-induced vascular changes in renovascular hypertension

Mounting evidence indicates that structural and functional vascular changes associated with two-kidney, one-clip (2K-1C) hypertension result, at least in part, from altered activity of matrix metalloproteinases (MMPs). Because MMPs are upregulated by increased formation of reactive oxygen species (ROS), we hypothesized that antioxidant approaches could attenuate the increases in MMP-2 expression/activity and the vascular dysfunction and remodeling associated with 2K-1C hypertension. Sham-operated or 2K-1C hypertensive rats were treated with tempol 18 mg/kg/day or apocyanin 25 mg/kg/day (or vehicle). Systolic blood pressure was monitored weekly. After 8 weeks of treatment, aortic rings were isolated to assess endothelium-dependent and -independent relaxation. Quantitative morphometry of structural changes in the aortic wall was studied in hematoxylin/eosin sections. Aortic and systemic ROS levels were measured using dihydroethidine and thiobarbituric acid-reactive substances, respectively. Aortic MMP-2 levels and activity were determined by gelatin and in situ zymography, fluorimetry, and immunohistochemistry. Tempol and apocyanin attenuated 2K-1C hypertension (181 ± 20.8 and 192 ± 17.6 mm Hg, respectively, versus 213 ± 18 mm Hg in hypertensive controls; both p < 0.05) and prevented the reduction in endothelium-dependent vasorelaxation found in 2K-1C rats. Tempol, but not apocyanin (p > 0.05), prevented the vascular remodeling found in 2K-1C rats (all p < 0.01). Tempol was more effective than apocyanin in attenuating hypertension-induced increases in oxidative stress (both p < 0.05), MMP-2 levels, and MMP-2 activity in hypertensive rats (all p < 0.05). Our results suggest that antioxidant approaches decrease MMP-2 upregulation and attenuate the vascular dysfunction and remodeling during 2K-1C hypertension.     

Identification of very potent inhibitor of human aminopeptidase N (CD13)

In this Letter we describe broad comparision studies toward rat, pig, and human aminopeptidase N (CD13) orthologs using phosphinate inhibitors related in structure to hydroxamic acids. This SAR approach yielded a very potent inhibitor of human aminopeptidase N: α₁-amino-3-phenylpropyl(α₂-hydroxy-3-phenylpropyl)phosphinic acid with an IC₅₀ = 60 nM.     

Testosterone may increase selective attention to threat in young male macaques

Animal studies indicate that sex hormones have widespread effects on the brain, cognition and emotion, but findings in humans are inconsistent. Well-controlled studies in nonhuman primates are crucial to resolve these discrepancies. In this study, we examined the effects of testosterone (T) on emotion in male rhesus monkeys. Six young adult males were tested on two emotional tasks during three hormonal conditions in a crossover design: when intact at baseline and when pharmacologically hypogonadal with add-back of T or placebo. The emotional tasks were the Approach–Avoidance task, which tested behavioral responses to three categories of objects (familiar, novel, and negative) and a Social Playback task which tested behavioral responses to scenes of unfamiliar conspecifics engaged in three types of social activities (neutral, positive, or negative). Following a 4-week baseline period, monkeys were treated with Depot Lupron, 200 μg/kg before being randomly assigned to one of two treatment groups: Depot Lupron + Testosterone Enanthate (TE, 20 mg/kg) or Depot Lupron + oil vehicle. In each treatment group, monkeys received one injection of Lupron and one injection of TE or one injection of Lupron and one injection of oil at the onset of a 4-week testing period, before crossing over to the alternate treatment for an additional 4 weeks of testing. TE treatment had no effect on behavioral measures in the Approach–Avoidance task. For the Social Playback task, however, TE significantly increased watching time of video clips which depicted fights between unfamiliar conspecifics. The enhancing effect of T on watching time for negative social scenes is consistent with human data suggesting that T decreases aversion or facilitates approach to threatening social stimuli. Further studies are needed to understand the mechanisms by which T may mediate responsiveness to social threat in male primates.     

Geometric morphometric analysis of giant honeybee (Apis dorsata Fabricius, 1793) populations in Thailand

Geometric morphometry was used to characterize 73 Apis dorsata colonies collected from 31 different localities in five major geographic regions of mainland Thailand. We measured 19 easily identified landmarks from the digitized images of the right forewing of 10 worker bees from each colony (730 bees in total); thus, avoiding the confounding variation from haploid or diploid males. After plotting the factor scores, A. dorsata from (mainland) Thailand were found to belong to a single group, which was further supported by a hierarchical cluster analysis-generated dendrogram. Multivariate analysis of variance (MANOVA, α = 0.05) demonstrated no significant differences among the five geographic groups of A. dorsata in Thailand, producing a low degree of accuracy (31.2%) in the identification of the geographic region from which any individual bee originated. Additionally, when the bee samples were classified into two groups, those north and south of the Isthmus of Kra were not significantly different (MANOVA, α = 0.05), and a low rate of correct classification in a cross-validation test (65% correct) was found. Therefore, this geometric morphometric based analysis of worker bee wing venation pattern suggests that A. dorsata populations in mainland Thailand are panmictic.     

Thermal tolerance and preference of exploited turbinid snails near their range limit in a global warming hotspot

Predicted global climate change has prompted numerous studies of thermal tolerances of marine species. The upper thermal tolerance is unknown for most marine species, but will determine their vulnerability to ocean warming. Gastropods in the family Turbinidae are widely harvested for human consumption. To investigate the responses of turbinid snails to future conditions we determined critical thermal maxima (CTMax) and preferred temperatures of Turbo militaris and Lunella undulata from the tropical-temperate overlap region of northern New South Wales, on the Australian east coast. CTMax were determined at two warming rates: 1 °C/30 min and 1 °C/12 h. The number of snails that lost attachment to the tank wall was recorded at each temperature increment. At the faster rate, T. militaris had a significantly higher CTMax (34.0 °C) than L. undulata (32.2 °C). At the slower rate the mean of both species was lower and there was no significant difference between them (29.4 °C for T. militaris and 29.6 °C for L. undulata). This is consistent with differences in thermal inertia possibly allowing animals to tolerate short periods at higher temperatures than is possible during longer exposure times, but other mechanisms are not discounted. The thermoregulatory behaviour of the turban snails was determined in a horizontal thermal gradient. Both species actively sought out particular temperatures along the gradient, suggesting that behavioural responses may be important in ameliorating short-term temperature changes. The preferred temperatures of both species were higher at night (24.0 °C and 26.0 °C) than during the day (22.0 °C and 23.9 °C). As the snails approached their preferred temperature, net hourly displacement decreased. Preferred temperatures were within the average seasonal seawater temperature range in this region. However, with future predicted water temperature trends, the species could experience increased periods of thermal stress, possibly exceeding CTMax and potentially leading to range contractions.     

Application of the index of marsh bird community integrity to coastal wetlands of Georgian Bay and Lake Ontario,Canada

Ecological indicators have gained increasing attention within the scientific community over the past 40 years. Several taxonomic groups have been used successfully as indicators including most prominently fish, invertebrates, plants, and birds because of their ability to indicate environmental changes. In the Laurentian Great Lakes region, there has been recent concern over the applicability of using indicators on a basin-wide scale due to species range restrictions and lake-based differences. The objective of this study was to determine the ability of the Index of Marsh Bird Community Integrity (IMBCI) to indicate land use disturbance surrounding coastal marshes of Georgian Bay and Lake Ontario. To meet this objective, we surveyed birds and vegetation at 14 marshes in Georgian Bay (low land use disturbance) and Lake Ontario (high land use disturbance). Even though Lake Ontario marshes were surrounded by significantly more altered land than Georgian Bay marshes, and had poorer water quality, we found significantly fewer birds in Georgian Bay marshes (mean = 8.2) compared to Lake Ontario (mean = 13.7) and no significant difference in IMBCI scores. This inconsistency could be due to vegetation differences affecting the strength of the index, because Georgian Bay wetlands had significantly more bulrush (Schoenoplectus spp.) and floating vegetation, while Lake Ontario wetland vegetation was taller and cattail-dominated (Typha spp.). These findings suggest that the IMBCI may not be useful on a basin-wide scale in the Great Lakes region in detecting human disturbance surrounding wetlands.     

Line and birth season effects on plasma testosterone and oxidative stress parameters in testis of maturing rabbits

Oxidative stress plays a key role in the male reproductive function. Differences between rabbit breeds have been found for testis size, seminiferous tubule diameter, number and size of interstitial and germ cells, etc. Traits related to the redox system could also be affected by genetic factors. It is likely that differences between breeds for these traits would lead to differences in reproductive maturation and fertility.We have investigated in the present paper the age-related changes of the plasma testosterone (TST) concentration, superoxide anion (O₂^?) radical formation, superoxide dismutase (SOD) activity, catalase (CAT) activity and thiobarbituric acid-reactive substances (TBARs) level in testis of rabbits in two breeds selected for different aptitudes (Caldes for growth rate and Prat for litter size). The effect of birth season for these traits was also assessed.Major changes in parameters related to oxidative stress were observed at an early age and most probably can be explained by the concomitant changes in testicular structure and function. Both lines showed similar developmental profiles and levels for all the variables studied. There was no interaction between line and birth season, consequently environmental conditions affected both lines in the same manner. Significant differences between males born in different seasons were found for O₂^? (4.84 ± 0.19 RLU/mg tissue min versus 5.67 ± 0.19 RLU/mg tissue min), SOD (6.12 ± 0.11 U/mg protein versus 7.09 ± 0.11 U/mg protein) and CAT (0.058 ± 0.002 K/mg protein versus 0.040 ± 0.002 K/mg protein). Future studies should take into account differences between seasons for a more precise analysis.     

Plazomicin is effective in a non-human primate pneumonic plague model

The efficacy of plazomicin for pneumonic plague was evaluated in a non-human primate model. African Green monkeys challenged with a lethal aerosol of Yersinia pestis [median (range) of 98 (15–331) LD_50s] received placebo (n = 12) or ‘humanized’ dose regimens (6.25, 12.5 or 25 mg/kg every 24 h) of plazomicin (n = 52) after the onset of fever for a duration of 5 or 10 days. All animals treated with placebo died, while 36 plazomicin-treated animals survived through study end. The majority (33/36) were either in the 10-day (high-/mid-/low-dose) or 5-day high-dose groups. The findings suggest an exposure range of plazomicin for treatment of pneumonic/bacteremic Y. pestis infection in humans.     

Prenatal androgen exposure and children's aggressive behavior and activity level

Some human behaviors, including aggression and activity level, differ on average for males and females. Here we report findings from two studies investigating possible relations between prenatal androgen and children's aggression and activity level. For study 1, aggression and activity level scores for 43 girls and 38 boys, aged 4 to 11 years, with congenital adrenal hyperplasia (CAH, a genetic condition causing increased adrenal androgen production beginning prenatally) were compared to those of similarly-aged, unaffected relatives (41 girls, 31 boys). Girls with CAH scored higher on aggression than unaffected girls, d = 0.69, and unaffected boys scored higher on activity level than unaffected girls, d = 0.50. No other group differences were significant. For study 2, the relationship of amniotic fluid testosterone to aggression and activity level was investigated in typically-developing children (48 girls, 44 boys), aged 3 to 5 years. Boys scored higher than girls on aggression, d = 0.41, and activity level, d = 0.50. However, amniotic fluid testosterone was not a significant predictor of aggression or activity level for either sex. The results of the two studies provide some support for an influence of prenatal androgen exposure on children's aggressive behavior, but not activity level. The within-sex variation in amniotic fluid testosterone may not be sufficient to allow reliable assessment of relations to aggression or activity level.     

Quantifying human disturbance on antipredator behavior and flush initiation distance in yellow-bellied marmots

Human disturbance may differentially affect the behavior of wild animals and such behavioral perturbations may have fitness consequences. To understand the effects of specific types of human disturbance on antipredator behavior, a behavior whose performance enhances survival, we studied yellow-bellied marmots (Marmota flaviventris). We quantified both antipredator vigilance and the flight initiation distance of the marmots to an approaching human in six different colony sites where we also quantified the frequency and type of human visitation. We developed an analysis framework, using linear mixed models, and found that: (1) when the presence of motorized vehicles and bicycles was high, marmots increased the proportion of time spent vigilant (pseudo R² = 0.33 and 0.31 for motorized vehicles and bicycles, P < 0.05) and decreased the time spent foraging (pseudo R² = 0.29 and 0.23 for motorized vehicles and bicycles, P < 0.05), (2) there was no significant effect of the presence of pedestrians on the time allocated to vigilance and foraging (pseudo R² = 0.25 and 0.19, P > 0.05), (3) marmots decreased the flight initiation distance as disturbance of motorized vehicles (pseudo R² = 0.85) and pedestrians (pseudo R² = 0.84) increased (P < 0.05), and (4) when we considered bicycles as the disturbance, juveniles tolerated closer approaches than adults or yearlings (P < 0.001). Marmots thus responded to some human disturbance by adjusting time spent in foraging and shortening the tolerance distance. Since these behavioral responses could have significant implications for survival and reproduction, we should generally view human disturbance as something that can influence natural antipredator behavior. Importantly, based on an understanding of the differential effects of human activities on wildlife, reducing human disturbance should be taken into account for wildlife management. In addition, our approach will be useful to quantify differential effects of humans on wildlife and to enhance our ability to manage those impacts.