Relationships between sex hormones assessed in amniotic fluid, and maternal and umbilical cord serum: what is the best source of information to investigate the effects of fetal hormonal exposure?

Levels of testosterone (T) (total and free), androstenedione (A4), dehydroepiandrosterone sulphate (DHEAS), sex hormone-binding globulin (SHBG), and estradiol (E2) were measured by radioimmunoassay (RIA) in 156 normal pregnancies (77 male and 79 female fetuses). Samples were obtained from amniotic fluid, 2nd and 3rd trimester maternal serum, and umbilical cord serum at birth. During the critical period of brain differentiation, at the beginning of the second trimester of pregnancy, sex differences in T and A4 were found in amniotic fluid and not in maternal serum. This finding adds to the fact that mostly low and nonsignificant correlations were found for the different androgenic hormones between levels assessed in amniotic fluid and maternal plasma at this particular and very sensitive period of fetal brain development. On the other hand, high correlations were found for the same hormones between the samples of maternal serum in the 2nd and the 3rd trimester. Our data show that, of all available sources, amniotic fluid seems to be the best candidate to investigate the effects of early fetal androgen exposure.     

Experimental evaluation of the relationship between lethal or non-lethal virulence and transmission success in malaria parasite infections

Background

Theoretical studies suggest that direct and indirect selection have the potential to cause substantial evolutionary change in female mate choice. Similarly, sexual selection is considered a strong force in the evolution of male attractiveness and the exaggeration of secondary sexual traits. Few studies have, however, directly tested how female mate choice and male attractiveness respond to selection. Here we report the results of a selection experiment in which we selected directly on female mating preference for attractive males and, independently, on male attractiveness in the guppy, Poecilia reticulata. We measured the direct and correlated responses of female mate choice and male attractiveness to selection and the correlated responses of male ornamental traits, female fecundity and adult male and female survival.

Results

Surprisingly, neither female mate choice nor male attractiveness responded significantly to direct or to indirect selection. Fecundity did differ significantly among lines in a way that suggests a possible sexually-antagonistic cost to male attractiveness.

Conclusions

The opportunity for evolutionary change in female mate choice and male attractiveness may be much smaller than predicted by current theory, and may thus have important consequences for how we understand the evolution of female mate choice and male attractiveness. We discuss a number of factors that may have constrained the response of female choice and male attractiveness to selection, including low heritabilities, low levels of genetic (co)variation in the multivariate direction of selection, sexually-antagonistic constraint on sexual selection and the "environmental covariance hypothesis".

     

Association of prenatal phenobarbital and phenytoin exposure with genital anomalies and menstrual disorders

BACKGROUND: Animal studies demonstrated that early exposure to phenobarbital decreases reproductive function. This study investigates whether prenatal exposure to these anticonvulsants affects human genital tract development. METHODS: Genital anomalies at birth were studied retrospectively in 90 phenobarbital-exposed, 108 phenobarbital plus phenytoin-exposed, and 198 matched control infants. Of this group, 72 drug-exposed males, 75 drug-exposed females, and 147 matched control subjects participated in a follow-up and were interviewed at age 19-35. Differences between groups were tested by chi-square and t-tests. RESULTS: A total of 15% of the phenobarbital-exposed boys versus 2.8% control boys had undescended testes at birth. More anticonvulsant-exposed (24%) than control males (11%) had received medical treatment for genital anomalies. Anticonvulsant-exposed females more often had irregularities in menstrual cycles (31% vs. 17%) and bleeding (15% vs. 3%) and reported more problems during pregnancy. CONCLUSIONS: Prenatal exposure to anticonvulsants seems to induce minor genital anomalies and may affect reproductive function.     

The Use of Bayesian Networks to Assess the Quality of Evidence from Research Synthesis: 2. Inter-Rater Reliability and Comparison with Standard GRADE Assessment

Background

The grades of recommendation, assessment, development and evaluation (GRADE) approach is widely implemented in systematic reviews, health technology assessment and guideline development organisations throughout the world. We have previously reported on the development of the Semi-Automated Quality Assessment Tool (SAQAT), which enables a semi-automated validity assessment based on GRADE criteria. The main advantage to our approach is the potential to improve inter-rater agreement of GRADE assessments particularly when used by less experienced researchers, because such judgements can be complex and challenging to apply without training. This is the first study examining the inter-rater agreement of the SAQAT.

Methods

We conducted two studies to compare: a) the inter-rater agreement of two researchers using the SAQAT independently on 28 meta-analyses and b) the inter-rater agreement between a researcher using the SAQAT (who had no experience of using GRADE) and an experienced member of the GRADE working group conducting a standard GRADE assessment on 15 meta-analyses.

Results

There was substantial agreement between independent researchers using the Quality Assessment Tool for all domains (for example, overall GRADE rating: weighted kappa 0.79; 95% CI 0.65 to 0.93). Comparison between the SAQAT and a standard GRADE assessment suggested that inconsistency was parameterised too conservatively by the SAQAT. Therefore the tool was amended. Following amendment we found fair-to-moderate agreement between the standard GRADE assessment and the SAQAT (for example, overall GRADE rating: weighted kappa 0.35; 95% CI 0.09 to 0.87).

Conclusions

Despite a need for further research, the SAQAT may aid consistent application of GRADE, particularly by less experienced researchers.     

Daily physical activity in ankylosing spondylitis: validity and reliability of the IPAQ and SQUASH and the relation with clinical assessments

Introduction

The aim of this study was to investigate the construct validity and test-retest reliability of the International Physical Activity Questionnaire (IPAQ; long form) and the Short QUestionnaire to Assess Health-enhancing physical activity (SQUASH) and to investigate the relation between daily physical activity and clinical assessments in patients with ankylosing spondylitis (AS).

Methods

For validity, the self-report questionnaires IPAQ and SQUASH were compared with daily physical activity assessed with the ActiGraph accelerometer during 7 consecutive days in 63 AS outpatients. For reliability, the IPAQ and SQUASH were administered twice approximately 1 week apart in 52 AS outpatients. In all 115 patients, clinical assessments were performed at the outpatient clinic.

Results

IPAQ and SQUASH total scores correlated significantly with accelerometer outcome: ρ = 0.38 and r = 0.35, respectively. Intraclass correlation coefficients between first and second assessments of the IPAQ and SQUASH were 0.83 and 0.89, respectively. Bland-Altman analyses showed no systemic bias, but in particular for the IPAQ the 95% limits of agreement were wide. Daily physical activity assessed by accelerometer, IPAQ, and SQUASH correlated significantly with disease activity, physical activity, and quality of life. A relation with spinal mobility was found only for the accelerometer and SQUASH. The direction of these correlations indicates that higher daily physical activity is related to lower disease activity and better physical function, spinal mobility and quality of life.

Conclusions

Both physical activity questionnaires showed modest construct validity. The SQUASH showed good test-retest reliability, superior to the IPAQ. These results indicate that the SQUASH is more suitable than the IPAQ to assess daily physical activity in AS population studies. However, it is desirable to add questions on AS-specific physical activity. Further studies are needed to investigate the causality of the relation between daily physical activity and clinical assessments.     

Salmonella Typhimurium-specific bacteriophage ΦSH19 and the origins of species specificity in the Vi01-like phage family

Background

PHYVV and PepGMV are plant viruses reported in Mexico and Southern US as causal agents of an important pepper disease known as "rizado amarillo". Mixed infections with PHYVV and PepGMV have been reported in several hosts over a wide geographic area. Previous work suggested that these viruses might interact at the replication and/or movement level in a complex manner. The aim of present report was to study some aspects of a synergistic interaction between PHYVV and PepGMV in pepper plants. These include analyses of symptom severity, viral DNA concentration and tissue localization of both viruses in single and mixed infections.

Results

Mixed infections with PepGMV and PHYVV induced symptoms more severe than those observed in single viral infections. Whereas plants infected with either virus (single infection) presented a remission stage with a corresponding decrease in viral DNA levels, double-infected plants did not present symptom remission and both viral DNA concentrations dramatically increased. In situ hybridization experiments revealed that both viruses are restricted to the vascular tissue. Interestingly, the amount of viral DNA detected was higher in plants inoculated with PepGMV than that observed in PHYVV-infected plants. During mixed infections, the location of both viruses remained similar to the one observed in single infections, although the number of infected cells increases. Infections with the tripartite mixture PHYVV (A+B) + PepGMV A produced a similar synergistic infection to the one observed after inoculation with both full viruses. On the contrary, tripartite mixture PepGMV (A+B) + PHYVV A did not produce a synergistic interaction. In an attempt to study the contribution of individual genes to the synergism, several mutants of PHYVV or PepGMV were inoculated in combination with the corresponding wild type, second virus (wt PepGMV or wt PHYVV). All combinations tested resulted in synergistic infections, with exception of the TrAP mutant of PepGMV (PepGMV TrAP-) + PHYVV.

Conclusion

In this report, we have demonstrated that synergistic interaction between PHYVV and PepGMV during a mixed infection is mainly due to an increased DNA concentration of both viruses, without any noticeable effect on the localization of either virus on infected plant tissue. Our results have shown that the viral component A from PepGMV is important for synergism during PHYVV-PepGMV mixed infections.     

Whole plant response of Pongamia pinnata to drought stress tolerance revealed by morpho-physiological,biochemical and transcriptome analysis

Molecular Biology Reports - Pongamia is considered an important biofuel species worldwide. Drought stress in the early growth stages of Pongamia influences negatively on the germination and...     

2D:4D finger-length ratios in children and adults with gender identity disorder

Previous research suggests that prenatal testosterone affects the 2D:4D finger ratio in humans, and it has been speculated that prenatal testosterone also affects gender identity differentiation. If both things are true, then one would expect to find an association between the 2D:4D ratio and gender identity. We measured 2D:4D in two samples of patients with gender identity disorder (GID). In Study 1, we compared the 2D:4D ratios of 96 adult male and 51 female patients with GID to that of 90 heterosexual male and 112 heterosexual female controls. In Study 2, we compared the 2D:4D ratios of 67 boys and 34 girls with GID to that of 74 control boys and 72 control girls. In the sample of adults with GID, we classified their sexual orientation as either homosexual or non-homosexual (in relation to their birth sex) to examine whether or not there were any within-group differences as a function of sexual orientation. In the sample of adult men with GID (both homosexual and non-homosexual) and children with GID, we found no evidence of an altered 2D:4D ratio relative to same-sex controls. However, women with GID had a significantly more masculinized ratio compared to the control women. This last finding was consistent with the prediction that a variance in prenatal hormone exposure contributes to a departure from a sex-typical gender identity in women.