Screening H3 Histone Acetylation in a Wild Bird, the House Sparrow (Passer Domesticus).

Epigenetic mechanisms are increasingly understood to have major impacts across ecology. However, one molecular epigenetic mechanism, DNA methylation, currently dominates the literature. A second mechanism, histone modification, is likely important to ecologically relevant phenotypes and thus warrants investigation, especially because molecular interplay between methylation and histone acetylation can strongly affect gene expression. There are a limited number of histone acetylation studies on non-model organisms, yet those that exist show that it can impact gene expression and phenotypic plasticity. Wild birds provide an excellent system to investigate histone acetylation, as free-living individuals must rapidly adjust to environmental change. Here, we screen histone acetylation in the house sparrow (Passer domesticus); we studied this species because DNA methylation was important in the spread of this bird globally. This species has one of the broadest geographic distributions in the world, and part of this success is related to the way that it uses methylation to regulate its gene expression. Here, we verify that a commercially available assay that was developed for mammals can be used in house sparrows. We detected high variance in histone acetylation among individuals in both liver and spleen tissue. Further, house sparrows with higher epigenetic potential in the Toll Like Receptor-4 (TLR-4) promoter (i.e., CpG content) had higher histone acetylation in liver. Also, there was a negative correlation between histone acetylation in spleen and TLR-4 expression. In addition to validating a method for measuring histone acetylation in wild songbirds, this study also shows that histone acetylation is related to epigenetic potential and gene expression, adding a new study option for ecological epigenetics.

Epigenetic and genetic variation among three separate introductions of the house sparrow (Passer domesticus) into Australia.

Invasive populations are often associated with low levels of genetic diversity owing to population bottlenecks at the initial stages of invasion. Despite this, the ability of invasive species to adapt rapidly in response to novel environments is well documented. Epigenetic mechanisms have recently been proposed to facilitate the success of invasive species by compensating for reduced levels of genetic variation. Here, we use methylation sensitive-amplification fragment length polymorphism and microsatellite analyses to compare levels of epigenetic and genetic diversity and differentiation across 15 sites in the introduced Australian house sparrow population. We find patterns of epigenetic and genetic differentiation that are consistent with historical descriptions of three distinct, introductions events. However unlike genetic differentiation, epigenetic differentiation was higher among sample sites than among invasion clusters, suggesting that patterns of epigenetic variation are more strongly influenced by local environmental stimuli or sequential founder events than the initial diversity in the introduction population. Interestingly, we fail to detect correlations between pairwise site comparisons of epigenetic and genetic differentiation, suggesting that some of the observed epigenetic variation has arisen independently of genetic variation. We also fail to detect the potentially compensatory relationship between epigenetic and genetic diversity that has been detected in a more recent house sparrow invasion in Africa. We discuss the potential for this relationship to be obscured by recovered genetic diversity in more established populations, and highlight the importance of incorporating introduction history into population-wide epigenetic analyses.

Genetic structure of Pseudococcus microcirculus (Hemiptera: Pseudococcidae) populations on epiphytic orchids in south Florida.

In 2012, the orchid mealy bug Pseudococcus microcirculus was first detected in situ in North America's more diverse orchid region, the Big Cypress Basin (Collier Co FL). A follow-up survey showed that the mealy bug is more widespread and found on epiphytic orchids in two locations, in both the Fakahatchee Strand State Preserve (sites B and F) and the Florida Panther National Wildlife Refuge (sites M and C). There, we collected mealy bugs (n = 54) from 35 orchid individuals and screened allelic variation at seven microsatellite loci. We estimated genetic diversity and differentiation among all sites and compared the variation among individuals collected on the same plant. Genetic differentiation between sites M and C (FST = 0.03, P < 0.01) and,Mand B (FST = 0.04, P < 0.01) was detected.We also detected significantly lower mean pairwise relatedness among individuals from site B compared to all the other locations, and this population had the lowest inbreeding coefficient. Genetic diversity and mean pairwise relatedness were highly variable among plants with multiple individuals; however, plants from sites F and M tend to have collections of individuals with higher mean pairwise relatedness compared to sites B and C. Our results indicate that there is genetic diversity and differentiation among mealy bugs in these locations, and that collections of individuals on the same plant are genetically diverse. As such, the mealy bugs throughout these areas are likely to be genetically diverse and exist in multiple distinct populations.

Genetic and epigenetic differences associated with environmental gradients in replicate populations of two salt marsh perennials.

While traits and trait plasticity are partly genetically based, investigating epigenetic mechanisms may provide more nuanced understanding of the mechanisms underlying response to environment. Using AFLP and methylation-sensitive AFLP, we tested the hypothesis that differentiation to habitats along natural salt marsh environmental gradients occurs at epigenetic, but not genetic loci in two salt marsh perennials. We detected significant genetic and epigenetic structure among populations and among subpopulations, but we found multilocus patterns of differentiation to habitat type only in epigenetic variation for both species. In addition, more epigenetic than genetic loci were correlated with habitat in both species. When we analysed genetic and epigenetic variation simultaneously with partial Mantel, we found no correlation between genetic variation and habitat and a significant correlation between epigenetic variation and habitat in Spartina alterniflora. In Borrichia frutescens, we found significant correlations between epigenetic and/or genetic variation and habitat in four of five populations when populations were analysed individually, but there was no significant correlation between genetic or epigenetic variation and habitat when analysed jointly across the five populations. These analyses suggest that epigenetic mechanisms are involved in the response to salt marsh habitats, but also that the relationships among genetic and epigenetic variation and habitat vary by species. Site-specific conditions may also cloud our ability to detect response in replicate populations with similar environmental gradients. Future studies analysing sequence data and the correlation between genetic variation and DNA methylation will be powerful to identify the contributions of genetic and epigenetic response to environmental gradients.

Within-genotype epigenetic variation enables broad niche width in a flower living yeast.

Niche theory is one of the central organizing concepts in ecology. Generally, this theory defines a given species niche as all of the factors that effect the persistence of the species as well as the impact of the species in a given location (Hutchinson 1957; Chase 2011). Many studies have argued that phenotypic plasticity enhances niche width because plastic responses allow organisms to express advantageous phenotypes in a broader range of environments (Bradshaw 1965; Van Valen 1965; Sultan 2001). Further, species that exploit habitats with fine-grained variation, or that form metapopulations, are expected to develop broad niche widths through phenotypic plasticity (Sultan & Spencer 2002; Baythavong 2011). Although a long history of laboratory, greenhouse and reciprocal transplant experiments have provided insight into how plasticity contributes to niche width (Pigliucci 2001), recent advances in molecular approaches allow for a mechanistic understanding of plasticity at the molecular level (Nicotra et al. 2010). In particular, variation in epigenetic effects is a potential source of the within-genotype variation that underlies the phenotypic plasticity associated with broad niche widths. Epigenetic mechanisms can alter gene expression and function without altering DNA sequence (Richards 2006) and may be stably transmitted across generations (Jablonka & Raz 2009; Verhoeven et al. 2010). Also, epigenetic mechanisms may be an important component of an individual's response to the environment (Verhoeven et al. 2010). While these ideas are intriguing, few studies have made a clear connection between genome-wide DNA methylation patterns and phenotypic plasticity (e.g. Bossdorf et al. 2010). In this issue of Molecular Ecology, Herrera et al. (2012) present a study that demonstrates epigenetic changes in genome-wide DNA methylation are causally active in a species' ability to exploit resources from a broad range of environments and are particularly important in harsh environments.

Hybridization between pallid sturgeon Scaphirhynchus albus and shovelnose sturgeon Scaphirhynchus platorynchus.

This study found that introgressive hybridization of the pallid sturgeon Scaphirhynchus albus with the common shovelnose sturgeon Scaphirhynchus platorynchus has probably occurred across the range of S. albus. Bayesian clustering found evidence of hybridization in all management units of S. albus. Some individuals were intermediate at both genetic and morphological characters, and some had discordant results. The results support introgressive hybridization throughout much of the range of S. albus, yet individuals consistent with being pure members of each species were detected in all management units. Simulations demonstrated that it would be very difficult to distinguish introgressed individuals from pure specimens after multiple generations of backcrossing with these microsatellite markers. Using hybrid or backcross fish as broodstock could artificially accelerate the loss of unique genetic variation in S. albus. Additional microsatellite loci or additional genetic markers, along with morphological data may be required to ensure that hybrid or backcross fish are not used. Introgressive hybridization requires at least two generations and generation lengths of S. albus are long, perhaps as long as 30 years. The proportion of individuals consistent with introgressive hybrid origins indicates that hybridization between S. albus and S. platorynchus probably has occurred for several generations and is not a recent phenomenon.

Broad-scale latitudinal patterns of genetic diversity among native European and introduced house sparrow (Passer domesticus) populations.

Introduced species offer unique opportunities to study evolution in new environments, and some provide opportunities for understanding the mechanisms underlying macroecological patterns. We sought to determine how introduction history impacted genetic diversity and differentiation of the house sparrow (Passer domesticus), one of the most broadly distributed bird species. We screened eight microsatellite loci in 316 individuals from 16 locations in the native and introduced ranges. Significant population structure occurred between native than introduced house sparrows. Introduced house sparrows were distinguished into one North American group and a highly differentiated Kenyan group. Genetic differentiation estimates identified a high magnitude of differentiation between Kenya and all other populations, but demonstrated that European and North American samples were differentiated too. Our results support previous claims that introduced North American populations likely had few source populations, and indicate house sparrows established populations after introduction. Genetic diversity also differed among native, introduced North American, and Kenyan populations with Kenyan birds being least diverse. In some cases, house sparrow populations appeared to maintain or recover genetic diversity relatively rapidly after range expansion (<50 years; Mexico and Panama), but in others (Kenya) the effect of introduction persisted over the same period. In both native and introduced populations, genetic diversity exhibited large-scale geographic patterns, increasing towards the equator. Such patterns of genetic diversity are concordant with two previously described models of genetic diversity, the latitudinal model and the species diversity model.

[Minimally invasive, safe treatment of the neurogenic bladder with botulinum-A-toxin in children with myelomeningocele]. / Minimalinvasive, sichere Behandlung der neurogenen Blase bei Myelomeningozelen-Kindern mit Botulinum-Toxin A.

PURPOSE: The efficacy and durability of botulinum-A toxin in the treatment of detrusor hyperreflexia in myelomeningocele (MMC) children was evaluated prospectively. MATERIALS AND METHODS: A total of 15 children (10 male and 5 female, mean age 5.8 years), all on clean intermittent catheterisation (CIC) due to MMC, were "non responders" to orally and intravesically administered anticholinergic medication. Pretreatment assessment included a videourodynamic evaluation, incontinence scoring and a mercaptoacetyltriglycine-3 renal scan. We injected from 10 U/kg up to a maximum of 360 U botulinum-A toxin at 25-40 sites of the detrusor, sparing the trigone. Follow-up was 24 months. All children had a urodynamic reevaluation with assessment of bladder capacity and incontinence score at 3, 9 and 12 months. RESULTS: Mean bladder reflex volume increased from 72.00 +/- 28.12 ml to 298 +/- 32.45 ml (p < 0.001). The maximal detrusor pressure decreased from 78.76 +/- 23.14 cm H(2)O to 42.76 +/- 24.34 cm H(2)O (p < 0.001). Maximal bladder capacity increased from 136.34 +/- 45.71 ml to 297.02 +/- 87.17 ml (p < 0.001). Detrusor compliance increased from 18.29 +/- 27.19 ml/cm H(2)O to 51.17 +/- 38.17 ml/mmH(2)O (p < 0.001). While 10 patients became completely dry between CIC, the remaining 2 patients improved from score 3 to 1. Results at 9 months were similar to the ones at 3 months. The mean efficacy and durability of the toxin was 10.5 months after the first intravesical injection. CONCLUSIONS: Botulinum-A toxin is a safe alternative in the management of detrusor hyperreflexia in MMC children. Preliminary results are promising concerning urodynamic parameters and continence.

Effect of hypothermia on blood-flow responses in pedicled groin flaps in rats.

Cooling is widely used for preserving tissues such as kidneys before transplantation and for preserving extremities before replantation. Hypothermia has also been shown to be effective in the temporary storage of free flaps. However, in the intact living body, cooling can be damaging to tissue and the body system. We used a custom-designed clamping method (after flap elevation, occlusion and release of the flap-feeding artery) and continuous laser Doppler flowmetry to investigate the effects of hypothermia on blood flow and postocclusive reactive hyperaemia in the flaps. The animal model used was the partially elevated epigastric flap of adult Sprague-Dawley rats. In the hypothermia group (n=12), the core temperature and the flap temperature were allowed to fall during anaesthesia. At core temperatures of 34.58 degrees C and 338 degrees C and after rewarming of the rat, the feeding artery was occluded for 30 s and 120 s to observe the changes in blood flow and postocclusive reactive hyperaemia in the flap. In the control group (n=12), the core temperature was maintained at more than 378 degrees C throughout the experiment. To compare the flap blood-flow responses to occlusion of the femoral artery in the hypothermia group and the control group, the postocclusive reactive hyperaemia periods (i.e. blood flow above baseline after clamp release) were analysed. Statistical analysis of the responses showed that the magnitude (P=0.024), duration (P<0.001) and amplitude (i.e. peak flow) (P=0.037) of postocclusive reactive hyperaemia were significantly decreased in the hypothermia group. Our results suggest that hypothermia significantly decreases blood flow and postocclusive reactive hyperaemia in the rat epigastric flap. This may increase the risk of ischaemic flap complications unless rewarming is performed.

The effect of promontorial bone on laser light transmission in measuring capillary blood flow in vivo.

Use of laser Doppler flowmetry (LDF) to assess cochlear blood flow (CBF) in experimental animals has elucidated the complex mechanisms in CBF regulation. Some attempts have been made to measure CBF in humans, although earlier studies produced confusing data about the physical possibility of LDF penetrating the human tympanic cavity promontory. In this study, we used LDF in an attempt to observe capillary blood flow in vivo through the intact human promontory in order to develop a method for measuring CBF in human patients. Temporal bones from six human cadavers were removed and the promontory overlying the basal turn of the cochlea was drilled off and fixed in 10% formalin. Perpendicular bone thickness was measured at the site of the stria vascularis. Seven young rats were anesthetized and the carotid artery was cannulated for blood pressure recording. Capillary flow was registered with LDF from two sites, the kidney and the plantar area of a hind limb, using a custom-designed probe with 632.8 nm and 780 nm wavelengths. Intravenous epinephrine was used to evoke blood flow changes. The same measurements were repeated through the promontorial bone. The light attenuation induced by the promontorial bone was 79+/-28% for the 632.8 nm wavelength, and 22+/-15 to 65+/-13% for the 780 nm wavelength, depending on the thickness of the bone. The sensitivity in detecting minute changes was 78% and 91-96%, respectively, for the 632.8 nm and 780 nm wavelengths. This study indicates that it is possible to detect minute changes in capillary blood flow through the intact human promontory at the site of the stria vascularis.

Changes in blood flow in the partially elevated epigastric pedicled flap in response to occlusion of the femoral artery in rats.

In this study, the authors used a custom-designed clamping method and laser Doppler flowmetry to investigate the short-term autoregulatory patterns of blood flow (BF) in partially elevated pedicled epigastric flaps in rats (n=11). The femoral artery was clamped for 30, 60, 120 and 180 sec directly after flap elevation and 40 to 80 min after flap elevation. Changes during and after clamping indicate the functioning of autoregulatory factors in the vessels of the epigastric partially elevated flap. The longer the clamp ischemia is in a flap, the greater (p < 0.0001) is the need for a compensatory increase in BF and for a longer time (p < 0.0001) in the flap after clamp release. They compared the responses of BF directly after flap elevation with those 40 to 80 min after flap elevation. The results suggest a significant increase in the autoregulatory capacity of the pedicled partially elevated flap in measurements performed 40 to 80 min after flap elevation (p = 0.043). They conclude that the novel clamping method seems to be reliable when studying the short-term autoregulatory patterns of the epigastric partially elevated pedicled flap.

[Value of ultrasound in microlithiasis of the testis in andrological patients]. / Die Bedeutung des Ultraschalls bei Mikrolithiasis des Hodens von andrologischen Patienten.

PURPOSE: The objective of this retrospective study is to show the importance of sonography in andrological patients with testicular microlithiasis (TM). PATIENTS AND METHODS: 1314 male patients were seen to our andrological clinic in the course of one year. The age range of these patients was 25 to 39 years (mean age 32 years). All patients underwent testicular sonography as well as a sperm-analysis. RESULTS: 284 patients showed normozoospermia without any evidence of TM. Of the remaining 1030 patients with a pathological spermiogram, 8 were shown to display more than 10 echogenic foci per transducer field in both tests. 1 patient suffering from an already palpable testicular tumor only showed, unilateral, unifocal calcification. Another patient who had suffered from a maldescensus testicle in his early childhood discharged only one unifocal calcification. Tumor markers including AFP and beta-HCG were normal in 9 patients, but elevated in 1 patient suffering from a testicular tumor (AFP: 73 kU/l; beta-HCG: 10.6 U/l). The hormonal status was normal in 6 patients and pathological 4 patients with the diagnosis of OAT-syndrome. CONCLUSION: TM is a rare condition even in andrological patients. Nevertheless, a thorough scrotal sonography is mandatory in order to rule out testicular malignancy.

Changes in blood flow in the epigastric free flap after microsurgical artery anastomoses in rats.

A number of clinical disorders of free vascularized flap are presumed to reflect insufficient blood flow (BF) or an inadequate range of vascular responsiveness. We compared the changes in BF in a pedicled and free epigastric flap, directly after and 90 min after performing microsurgical artery anastomoses. We used the clamping method and laser Doppler flowmetry in six Sprague-Dawley rats. The BF response curves shortly after re-anastomosing of the artery differ markedly from those in a pedicled flap model and curves registered 90 min after performing the anastomosis. We conclude that the clamping method is reliable and reproducible when studying the short-term autoregulatory BF patterns of epigastric pedicled and free flaps.

[Prostaglandin E1 injection in erectile dysfunction. Current diagnostic and therapeutic possibilities]. / Prostaglandin-E1-Injektion bei erektiler Dysfunction. Neue diagnostische und therapeutische Möglichkeiten.

In erectile dysfunction formerly, for both diagnostic and therapeutic purposes, intracavernous injections of papaverine and the combination papaverine/phentolamine were employed. In recent years, promising results have been reported with prostaglandin E1. In a multicenter study, 10 to 20 micrograms prostaglandin E1 were administered for testing corpus cavernosum function. One hundred and fifteen out of 187 patients self-injected themselves with prostaglandin E1 at an average dose of about 13 micrograms. While priapism occurred in 5 to 10% of the patients injecting papaverine or papaverine/phentolamine, and fibrosis and tunica induration in 10 to 57% patients on long-term treatment, the risk of priapism was low in prostaglandin E1. Subsequently, induration and penile deviation were reported in 2 patients each. In this multicenter study, a subjective efficacy of more than 90% was observed, thus confirming similar results with prostaglandin E1 found in other studies. The present results show that prostaglandin E1 can be considered the drug of first choice for intracavernous injection treatment of erectile dysfunction.