The effect of follicular fluid hormones on oocyte recovery after ovarian stimulation: FSH level predicts oocyte recovery

Background  

Ovarian stimulation for assisted reproductive technology (ART) overcomes the physiologic process to develop a single dominant follicle. However, following stimulation, egg recovery rates are not 100%. The objective of this study is to determine if the follicular fluid hormonal environment is associated with oocyte recovery.     

Balancing Fairness and Efficiency: The Impact of Identity-Blind and Identity-Conscious Accountability on Applicant Screening

This study compared two forms of accountability that can be used to promote diversity and fairness in personnel selections: identity-conscious accountability (holding decision makers accountable for which groups are selected) versus identity-blind accountability (holding decision makers accountable for making fair selections). In a simulated application screening process, undergraduate participants (majority female) sorted applicants under conditions of identity-conscious accountability, identity-blind accountability, or no accountability for an applicant pool in which white males either did or did not have a human capital advantage. Under identity-conscious accountability, participants exhibited pro-female and pro-minority bias, particularly in the white-male-advantage applicant pool. Under identity-blind accountability, participants exhibited no biases and candidate qualifications dominated interview recommendations. Participants exhibited greater resentment toward management under identity-conscious accountability.     

Quantitative imaging of pO2 in orthotopic murine gliomas: hypoxia correlates with resistance to radiation

Hypoxia is considered one of the microenvironmental factors associated with the malignant nature of glioblastoma. Thus, evaluating intratumoural distribution of hypoxia would be useful for therapeutic planning as well as assessment of its effectiveness during the therapy. Electron paramagnetic resonance imaging (EPRI) is an imaging technique which can generate quantitative maps of oxygen in vivo using the exogenous paramagnetic compound, triarylmethyl and monitoring its line broadening caused by oxygen. In this study, the feasibility of EPRI for assessment of oxygen distribution in the glioblastoma using orthotopic U87 and U251 xenograft model is examined. Heterogeneous distribution of pO₂ between 0 and 50?mmHg was observed throughout the tumours except for the normal brain tissue. U251 glioblastoma was more likely to exhibit hypoxia than U87 for comparable tumour size (median pO₂; 29.7 and 18.2?mmHg, p?=?.028, in U87 and U251, respectively). The area with pO₂ under 10?mmHg on the EPR oximetry (HF10) showed a good correlation with pimonidazole staining among tumours with evaluated size. In subcutaneous xenograft model, irradiation was relatively less effective for U251 compared with U87. In conclusion, EPRI is a feasible method to evaluate oxygen distribution in the brain tumour.     

Convergent evolution in social swallows (Aves: Hirundinidae)

Behavioral shifts can initiate morphological evolution by pushing lineages into new adaptive zones. This has primarily been examined in ecological behaviors, such as foraging, but social behaviors may also alter morphology. Swallows and martins (Hirundinidae) are aerial insectivores that exhibit a range of social behaviors, from solitary to colonial breeding and foraging. Using a well‐resolved phylogenetic tree, a database of social behaviors, and morphological measurements, we ask how shifts from solitary to social breeding and foraging have affected morphological evolution in the Hirundinidae. Using a threshold model of discrete state evolution, we find that shifts in both breeding and foraging social behavior are common across the phylogeny of swallows. Solitary swallows have highly variable morphology, while social swallows show much less absolute variance in all morphological traits. Metrics of convergence based on both the trajectory of social lineages through morphospace and the overall morphological distance between social species scaled by their phylogenetic distance indicate strong convergence in social swallows, especially socially foraging swallows. Smaller physical traits generally observed in social species suggest that social species benefit from a distinctive flight style, likely increasing maneuverability and foraging success and reducing in‐flight collisions within large flocks. These results highlight the importance of sociality in species evolution, a link that had previously been examined only in eusocial insects and primates.     

Male-Driven Differences in Chimpanzee (<Emphasis Type="Italic">Pan troglodytes</Emphasis>) Population Genetic Structure Across Three Habitats in Cameroon and Nigeria

Complex ecological pressures affect the social dynamics of many primate species, but it is unclear how they affect primate speciation. Molecular tools are often used to answer questions about the evolutionary histories and social systems of primates. Mitochondrial DNA (mtDNA), in particular, is frequently used to answer many of these questions, but because it is passed from mothers to offspring it reveals only the histories of females. In many species, including chimpanzees, females generally disperse from their natal groups while males are philopatric, and thus differences in dispersal patterns likely leave different signatures in the genome. We previously analyzed samples from 187 unrelated male and female chimpanzees in Nigeria and Cameroon using 21 autosomal microsatellites and mtDNA sequences. Here, we examine the contributions of males and females in shaping the genetic history of these chimpanzees by genotyping a subset of 56 males at 12 Y-chromosome microsatellites. We found that Y-chromosome population structure differed from the results of analysis of mtDNA haplotypes. The results also revealed that males in rainforest habitats (Guinean and Congolian rainforests) are more closely related to one another than those inhabiting the savanna-woodland mosaic ecotone in central Cameroon. In contrast, the pattern of female relatedness did not differ across habitats. We hypothesize that these differences in population structure and patterns of relatedness among males in different habitat types may be due to differences in the community dynamics of chimpanzees in the ecotone vs. rainforests, and that these factors contribute to making Cameroon an engine of diversification for chimpanzees. Broadly, these results demonstrate the importance of habitat variation in shaping social systems, population genetics, and primate speciation.     

Expression in Escherichia coli and characterization of the heat-stable inhibitor of the cAMP-dependent protein kinase

Pure heat-stable inhibitor of the cAMP-dependent protein kinase (PKI) has been isolated in high yield by using a bacterial expression vector constructed to synthesize the complete sequence of the rabbit muscle protein kinase inhibitor, plus an amino-terminal initiator methionine and glycine. Bacterially expressed PKI has an inhibitory activity identical to that of the protein isolated from rabbit skeletal muscle and, by gel filtration and gel electrophoresis, has the same physicochemical characteristics as the native physiological form of PKI. Fourier transformed infrared spectroscopy and CD establish that PKI has unusually large amounts of random coil and turn structures, with significantly smaller amounts of alpha-helix and beta structures.     

Distributions of Virus-Like Particles and Prokaryotes within Microenvironments

Microbial interactions are important for ecosystem function, but occur at the microscale and so are difficult to observe. Previous studies in marine systems have shown significant shifts in microbial community abundance and composition over scales of micrometres to centimetres. This study investigates the microscale abundance distributions of virus-like particles (VLPs) and prokaryotes in the lower reaches of a river to determine the extent to which microscale microbial patchiness exists in freshwater systems. Here we report local hotspots surrounded by gradients that reach a maximum 80 and 107 fold change in abundance over 0.9 cm for prokaryotic and VLP subpopulations. Changes in prokaryotic and VLP hotspots were tightly coupled. There were no gradients at tens of centimetres across the boundary layers, which is consistent with strong mixing and turbulence-driven aggregation found in river systems. Quantification of the patchiness shows a marked asymmetry with patches 10 times greater than background common, but depletions being rare or absent in most samples. This consistent asymmetry suggests that coldspots depleted by grazing and lysis are rapidly mixed to background concentrations, while the prevalence of hotspots indicates persistence against disruption. The hotspot to coldspot relative abundance may be useful for understanding microbial river dynamics. The patchiness indicates that the mean- field approach of bulk phase sampling misses the microbially relevant community variation and may underestimate the concentrations of these important microbial groups.     

Modulation of striatal [3H]-glutamic acid release by dopaminergic drugs

Potassium induced release of [³H]-glutamic acid which had been recently taken up into striatal tissue in vitro was demonstrated and shown to be predominantly Ca²⁺-dependent. Dopamine and several DA agonists produced marked inhibition of this K⁺ -induced release which could be antagonised by butyrophenones. The effect of DA could not be mimicked by high concentrations of dibutyryl cAMP. These results are consistent with the existence of a D2-like DA receptor on striatal glutamatergic terminals capable of modulating the transmitter release.