bluuebunny/crossref_metadata_2025_split huggingface dataset:
Does Dynorphin Play a Role in the Onset of Puberty in Female Sheep?
Authors: Lopez J. A. , Bedenbaugh M. N. , McCosh R. B. , Weems P. W. , Meadows L. J. , Wisman B. , Coolen L. M. , Goodman R. L. , Hileman S. M. 
Published: November 2016

Puberty onset involves increased gonadotrophin‐release (GnRH) release as a result of decreased sensitivity to oestrogen (E2)‐negative feedback. Because GnRH neurones lack E2 receptor α, this pathway must contain interneurones. One likely candidate is KNDy neurones (kisspeptin, neurokinin B, dynorphin). The overarching hypothesis of the present study was that the prepubertal hiatus in luteinising hormone (LH) release involves reduced kisspeptin and/or heightened dynorphin input. We first tested the specific hypothesis that E2 would reduce kisspeptin‐immunopositive cell numbers and increase dynorphin‐immunopositive cell numbers. We found that kisspeptin cell numbers were higher in ovariectomised (OVX) lambs than OVX lambs treated with E2 (OVX+ E2) or those left ovary‐intact. Very few arcuate dynorphin cells were identified in any group. Next, we hypothesised that central blockade of κ‐opioid receptor (KOR) would increase LH secretion at a prepubertal (6 months) but not postpubertal (10 months) age. Luteinising hormone pulse frequency and mean LH increased during infusion of a KOR antagonist, norbinaltorphimine, in OVX + E2 lambs at the prepubertal age but not in the same lambs at the postpubertal age. We next hypothesised that E2 would increase KOR expression in GnRH neurones or alter synaptic input to KNDy neurones in prepubertal ewes. Oestrogen treatment decreased the percentage of GnRH neurones coexpressing KOR (approximately 68%) compared to OVX alone (approximately 78%). No significant differences in synaptic contacts per cell between OVX and OVX + E2 groups were observed. Although these initial data are consistent with dynorphin inhibiting pulsatile LH release prepubertally, additional work will be necessary to define the source and mechanisms of this inhibition.
A current perspective on apomixis in ferns
Authors: Grusz Amanda L. 
Published: November 2016

AbstractThis review provides a synopsis of apogamous reproduction in ferns and highlights important progress made in recent studies of fern apomixis. First, a summary of the apomictic fern life cycle is provided, distinguishing between two pathways to diploid spore production that have been documented in apomictic ferns (premeiotic endomitosis and meiotic first division restitution) and briefly discussing the evolutionary implications of each. Next, recent trends in fern apomixis research are discussed, exposing a shift in focus from the observation and characterization of apomixis in ferns to more integrated studies of the evolutionary and ecological implications of this reproductive mode. Peer‐reviewed contributions from the past decade are then summarized, spanning the identification of new apomictic lineages through to the developmental, phylogenetic, and population genetic insights that have been made in studies of fern apomixis during that time. Gaps in our understanding are also discussed, including the extent and implications of recombinant apomixis in ferns, the possible reversibility of reproductive mode (from apomictic to sexual) in ferns, and the genomic causes and consequences of apomixis in seed free vascular plants. To conclude, future directions for fern apomixis research are proposed in the context of modern technological advances and recent insights from studies of apomixis in other groups.
Prevention of allograft HCV recurrence with peri‐transplant human monoclonal antibody MBL‐HCV1 combined with a single oral direct‐acting antiviral: A proof‐of‐concept study
Authors: Smith H. L. , Chung R. T. , Mantry P. , Chapman W. , Curry M. P. , Schiano T. D. , Boucher E. , Cheslock P. , Wang Y. , Molrine D. C. 
Published: November 2016

SummaryPatients with active hepatitis C virus (HCV) infection at transplantation experience rapid allograft infection, increased risk of graft failure and accelerated fibrosis. MBL‐HCV1, a neutralizing human monoclonal antibody (mAb) targeting the HCV envelope, was combined with a licensed oral direct‐acting antiviral (DAA) to prevent HCV recurrence post‐transplant in an open‐label exploratory efficacy trial. Eight subjects received MBL‐HCV1 beginning on the day of transplant with telaprevir initiated between days 3 and 7 post‐transplantation. Following FDA approval of sofosbuvir, two subjects received MBL‐HCV1 starting on the day of transplant with sofosbuvir initiated on day 3. Combination treatment was administered for 8‐12 weeks or until the stopping rule for viral rebound was met. The primary endpoint was undetectable HCV RNA at day 56 with exploratory endpoints of sustained virologic response (SVR) at 12 and 24 weeks post‐treatment. Both subjects receiving mAb and sofosbuvir achieved SVR24. Four of eight subjects in the mAb and telaprevir group met the primary endpoint; one subject achieved SVR24 and three subjects relapsed 2‐12 weeks post‐treatment. The other four subjects experienced viral breakthrough. There were no serious adverse events related to study treatment. This proof‐of‐concept study demonstrates that peri‐transplant immunoprophylaxis combined with a single oral direct‐acting antiviral in the immediate post‐transplant period can prevent HCV recurrence.
Effect of moderate shock waves on magnetic susceptibility and microstructure of a magnetite‐bearing ore
Authors: Reznik Boris , Kontny Agnes , Fritz Jörg 
Published: November 2016

AbstractThis study demonstrates a relationship between changes of magnetic susceptibility and microstructure developing in minerals of a magnetite‐bearing ore, experimentally shocked to pressures of 5, 10, 20, and 30 GPa. Shock‐induced effects on magnetic properties were quantified by bulk magnetic susceptibility measurements while shock‐induced microstructures were studied by high‐resolution scanning electron microscopy. Microstructural changes were compared between magnetite, quartz, amphibole, and biotite grains. In the 5 GPa sample, a sharp drop of magnetic susceptibility correlates with distinct fragmentation as well as with formation of shear bands and twins in magnetite. At 10 GPa, shear bands and twins in magnetite are accompanied by droplet‐shaped nanograins. In this shock pressure regime, quartz and amphibole still show intensive grain fragmentation. Twins in quartz and foam‐shaped, highly porous amphibole are formed at 20 and 30 GPa. The formation of porous minerals suggests that shock heating of these mineral grains resulted in localized temperature spikes. The identified shock‐induced features in magnetite strongly advise that variations in the bulk magnetic susceptibility result from cooperative grain fragmentation, plastic deformation and/or localized amorphization, and probably postshock annealing. In particular, the increasing shock heating at high pressures is assumed to be responsible for a partial defect annealing which we suggest to be responsible for the almost constant values of magnetic susceptibility above 10 GPa.
An autopsied case of MV2K + C‐type sporadic Creutzfeldt‐Jakob disease presenting with widespread cerebral cortical involvement and Kuru plaques
Authors: Iwasaki Yasushi , Saito Yufuko , Aiba Ikuko , Kobayashi Atsushi , Mimuro Maya , Kitamoto Tetsuyuki , Yoshida Mari 
Published: November 2016

MV2‐type sporadic Creutzfeldt‐Jakob disease (sCJD), which was previously called “Kuru‐plaque variant”, was gradually revealed to have a wide spectrum and has been classified into three pathological subtypes: MV2K, MV2C and MV2K + C. We herein describe the detailed clinical findings and neuropathologic observations from an autopsied MV2K + C‐type Japanese sCJD case with widespread cerebral cortical pathology and Kuru plaques. In the early stages of the disease, the patient exhibited gait disturbance with ataxia and dysarthria as well as gradual appearance of cognitive dysfunction. Diffusion‐weighted images (DWI) on MRI revealed extensive cerebral cortical hyperintensity. Pathologic investigation revealed extensive spongiform change in the cerebral cortex, particularly in the deeper layers. Vacuole size varied, and some were confluent. Prion protein (PrP) immunostaining revealed extensive PrP deposition in the cerebral cortex, basal ganglia, thalamus, cerebellum, brainstem and spinal cord. In the cerebral cortex, synaptic‐type, Kuru plaque‐like, and coarse plaque‐type PrP depositions were mainly observed, along with some perivacuolar‐type PrP depositions. Kuru plaques and coarse plaque‐type PrP depositions also were observed in the cerebellar cortex. PrP gene analysis revealed no mutations, and polymorphic codon 129 exhibited Met/Val heterozygosity. Western blot analysis revealed a mixture of intermediate‐type PrPSc and type 2 PrPSc. Based on previous reports regarding MV2‐type sCJD and the clinicopathologic findings of the present case, we speculated that it may be possible to clinically distinguish each MV2 subtype. Clinical presentation of the MV2K + C subtype includes predominant cerebral cortical involvement signs with ataxia and DWI hyperintensity of the cerebral cortex on MRI.
Rotenone and elevated extracellular potassium concentration induce cell‐specific fibrillation of α‐synuclein in axons of cholinergic enteric neurons in the guinea‐pig ileum
Authors: Sharrad D. F. , Chen B. N. , Gai W. P. , Vaikath N. , El‐Agnaf O. M. , Brookes S. J. H. 
Published: November 2016

AbstractBackgroundParkinson's disease is a progressive neurodegenerative disorder that results in the widespread loss of select classes of neurons throughout the nervous system. The pathological hallmarks of Parkinson's disease are Lewy bodies and neurites, of which α‐synuclein fibrils are the major component. α‐Synuclein aggregation has been reported in the gut of Parkinson's disease patients, even up to a decade before motor symptoms, and similar observations have been made in animal models of disease. However, unlike the central nervous system, the nature of α‐synuclein species that form these aggregates and the classes of neurons affected in the gut are unclear. We have previously reported selective expression of α‐synuclein in cholinergic neurons in the gut (J Comp Neurol. 2013;521:657), suggesting they may be particularly vulnerable to degeneration in Parkinson's disease.MethodsIn this study, we used immunohistochemistry to detect α‐synuclein oligomers and fibrils via conformation‐specific antibodies after rotenone treatment or prolonged exposure to high [K+] in ex vivo segments of guinea‐pig ileum maintained in organotypic culture.Key ResultsRotenone and prolonged raising of [K+] caused accumulation of α‐synuclein fibrils in the axons of cholinergic enteric neurons. This took place in a time‐ and, in the case of rotenone, concentration‐dependent manner. Rotenone also caused selective necrosis, indicated by increased cellular autofluorescence, of cholinergic enteric neurons, labeled by ChAT‐immunoreactivity, also in a concentration‐dependent manner.Conclusions & InferencesTo our knowledge, this is the first report of rotenone causing selective loss of a neurochemical class in the enteric nervous system. Cholinergic enteric neurons may be particularly susceptible to Lewy pathology and degeneration in Parkinson's disease.
Acute sacral nerve stimulation reduces visceral mechanosensitivity in a cross‐organ sensitization model
Authors: Langlois L. D. , Le Long E. , Meleine M. , Antor M. , Atmani K. , Dechelotte P. , Leroi A. M. , Gourcerol G. 
Published: November 2016

AbstractBackgroundSacral nerve stimulation (SNS) is a surgical treatment of fecal and urinary incontinence that consists of inserting a stimulating electrode into one of the s3 or s4 sacral holes. In addition to the benefit of SNS in the treatment of incontinence, recent studies showed that SNS is effective in the treatment of irritable bowel syndrome as well as bladder pain syndrome. The aim of this study was to evaluate the effect of SNS on visceral mechanosensitivity in a cross‐organ sensitization rat model.MethodsHypersensitive model was obtained by instillation of acetic acid into the bladder of rats during 5 minutes, 30 minutes before the start of the experiments. Visceral sensitivity was assessed by monitoring the change in mean arterial pressure in response to graded isobaric colorectal distension series. To decipher the mechanisms underlying SNS effect, rats were administered intravenously either a nonselective opioid receptor antagonist (naloxone) or a nitric oxide synthesis antagonist (L‐NAME). Neuronal activation in the dorsal horn of the sacral spinal cord was measured by counting c‐fos immunoreactive cells in response to colorectal distension and NMS.Key ResultsIntravesical acetic acid instillation increased mean arterial pressure variation in response to colorectal distension when compared to saline group. SNS reduced the variation in arterial pressure. Colorectal distension induced a rise in c‐fos immunoreactive cells in the dorsal horn of the spinal cord. This effect was reduced by SNS.Conclusions & InferencesSNS reduces visceral mechanosensitivity in a cross‐organ sensitization model.
An enigmatic Hawaiian moth is a missing link in the adaptive radiation of Schiedea
Authors: Weller Stephen G. , Sakai Ann K. , Campbell Diane R. , Powers John M. , Peña Sean R. , Keir Matthew J. , Loomis Alexander K. , Heintzman Scott M. , Weisenberger Lauren 
Published: November 2016

Summary

Shifts in pollination may drive adaptive diversification of reproductive systems within plant lineages. The monophyletic genus Schiedea is a Hawaiian lineage of 32 extant species, with spectacular diversity in reproductive systems. Biotic pollination is the presumed ancestral condition, but this key element of the life history and its role in shaping reproductive systems has remained undocumented.

We observed floral visitors to two species of Schiedea and conducted field experiments to test pollinator effectiveness. We used choice tests to compare attraction of pollinators to species hypothesized to be biotically vs wind‐pollinated.

Pseudoschrankia brevipalpis (Erebidae), a recently described moth species known only from O‘ahu, visited hermaphroditic Schiedea kaalae and S. hookeri and removed nectar from their unique tubular nectary extensions. Pseudoschrankia brevipalpis effectively pollinates S. kaalae; single visits to emasculated flowers resulted in pollen transfer. In choice tests, P. brevipalpis strongly preferred these hermaphroditic species over two subdioecious species capable of wind pollination.

A shift from biotic to abiotic pollination is clearly implicated in the diversification of reproductive systems within Schiedea. Abundant pollination by a previously unknown native moth in experimental and restored populations suggests the potential for restoration to re‐establish native plant–pollinator interactions critical for production of outcrossed individuals with high fitness.
Changes to Cretaceous surface fire behaviour influenced the spread of the early angiosperms
Authors: Belcher Claire M. , Hudspith Victoria A. 
Published: November 2016

SummaryAngiosperms evolved and diversified during the Cretaceous period. Early angiosperms were short‐stature weedy plants thought to have increased fire frequency and mortality in gymnosperm forest, aiding their own expansion. However, no explorations have considered whether the range of novel fuel types that diversified throughout the Cretaceous also altered fire behaviour, which should link more strongly to mortality than fire frequency alone.We measured ignitability and heat of combustion in analogue Cretaceous understorey fuels (conifer litter, ferns, weedy and shrubby angiosperms) and used these data to model palaeofire behaviour.Variations in ignition, driven by weedy angiosperms alone, were found to have been a less important feedback to changes in Cretaceous fire activity than previously estimated. Our model estimates suggest that fires in shrub and fern understories had significantly greater fireline intensities than those fuelled by conifer litter or weedy angiosperms, and whilst fern understories supported the most rapid fire spread, angiosperm shrubs delivered the largest amount of heat per unit area.The higher fireline intensities predicted by the models led to estimates of enhanced scorch of the gymnosperm canopy and a greater chance of transitioning to crown fires. Therefore, changes in fire behaviour driven by the addition of new Cretaceous fuel groups may have assisted the angiosperm expansion.
Regional heritability mapping and genome‐wide association identify loci for complex growth, wood and disease resistance traits in Eucalyptus
Authors: Resende Rafael Tassinari , Resende Marcos Deon Vilela , Silva Fabyano Fonseca , Azevedo Camila Ferreira , Takahashi Elizabete Keiko , Silva‐Junior Orzenil Bonfim , Grattapaglia Dario 
Published: November 2016

Summary

Although genome‐wide association studies (GWAS) have provided valuable insights into the decoding of the relationships between sequence variation and complex phenotypes, they have explained little heritability. Regional heritability mapping (RHM) provides heritability estimates for genomic segments containing both common and rare allelic effects that individually contribute too little variance to be detected by GWAS.

We carried out GWAS and RHM for seven growth, wood and disease resistance traits in a breeding population of 768 Eucalyptus hybrid trees using EuCHIP60K. Total genomic heritabilities accounted for large proportions (64–89%) of pedigree‐based trait heritabilities, providing additional evidence that complex traits in eucalypts are controlled by many sequence variants across the frequency spectrum, each with small contributions to the phenotypic variance.

RHM detected 26 quantitative trait loci (QTLs) encompassing 2191 single nucleotide polymorphisms (SNPs), whereas GWAS detected 13 single SNP–trait associations. RHM and GWAS QTLs individually explained 5–15% and 4–6% of the genomic heritability, respectively. RHM was superior to GWAS in capturing larger proportions of genomic heritability. Equated to previously mapped QTLs, our results highlighted genomic regions for further examination towards gene discovery.

RHM‐QTLs bearing a combination of common and rare variants could be useful enhancements to incorporate prior knowledge of the underlying genetic architecture in genomic prediction models.
Evolution of ectomycorrhizas as a driver of diversification and biogeographic patterns in the model mycorrhizal mushroom genus Laccaria
Authors: Wilson Andrew W. , Hosaka Kentaro , Mueller Gregory M. 
Published: November 2016

Summary

A systematic and evolutionary ecology study of the model ectomycorrhizal (ECM) genus Laccaria was performed using herbarium material and field collections from over 30 countries covering its known geographic range.

A four‐gene (nrITS, 28S, RPB2, EF1α) nucleotide sequence dataset consisting of 232 Laccaria specimens was analyzed phylogenetically. The resulting Global Laccaria dataset was used for molecular dating and estimating diversification rates in the genus. Stable isotope analysis of carbon and nitrogen was used to evaluate the origin of Laccaria's ECM ecology.

In all, 116 Laccaria molecular species were identified, resulting in a near 50% increase in its known diversity, including the new species described herein: Laccaria ambigua. Molecular dating indicates that the most recent common ancestor to Laccaria existed in the early Paleocene (56–66 million yr ago), probably in Australasia. At this time, Laccaria split into two lineages: one represented by the new species L. ambigua, and the other reflecting a large shift in diversification that resulted in the remainder of Laccaria. L. ambigua shows a different isotopic profile than all other Laccaria species.

Isotopes and diversification results suggest that the evolution of the ECM ecology was a key innovation in the evolution of Laccaria. Diversification shifts associated with Laccaria's dispersal to the northern hemisphere are attributed to adaptations to new ecological niches.
Co‐expression of peppermint geranyl diphosphate synthase small subunit enhances monoterpene production in transgenic tobacco plants
Authors: Yin Jun‐Lin , Wong Woon‐Seng , Jang In‐Cheol , Chua Nam‐Hai 
Published: November 2016

Summary

Monoterpenes are important for plant survival and useful to humans. In addition to their function in plant defense, monoterpenes are also used as flavors, fragrances and medicines. Several metabolic engineering strategies have been explored to produce monoterpene in tobacco but only trace amounts of monoterpenes have been detected.

We investigated the effects of Solanum lycopersicum 1‐deoxy‐d‐xylulose‐5‐phosphate synthase (SlDXS), Arabidopsis thaliana geranyl diphosphate synthase 1 (AtGPS) and Mentha × piperita geranyl diphosphate synthase small subunit (MpGPS.SSU) on production of monoterpene and geranylgeranyl diphosphate (GGPP) diversities, and plant morphology by transient expression in Nicotiana benthamiana and overexpression in transgenic Nicotiana tabacum.

We showed that MpGPS.SSU could enhance the production of various monoterpenes such as (−)‐limonene, (−)‐linalool, (−)‐α‐pinene/β‐pinene or myrcene, in transgenic tobacco by elevating geranyl diphosphate synthase (GPS) activity. In addition, overexpression of MpGPS.SSU in tobacco caused early flowering phenotype and increased shoot branching by elevating contents of GA3 and cytokinins due to upregulated transcript levels of several plastidic 2‐C‐methyl‐d‐erythritol‐4‐phosphate (MEP) pathway genes, geranylgeranyl diphosphate synthases 3 (GGPPS3) and GGPPS4.

Our method would allow the identification of new monoterpene synthase genes using transient expression in N. benthamiana and the improvement of monoterpene production in transgenic tobacco plants.
The response of ecosystem water‐use efficiency to rising atmospheric CO2 concentrations: sensitivity and large‐scale biogeochemical implications
Authors: Knauer Jürgen , Zaehle Sönke , Reichstein Markus , Medlyn Belinda E. , Forkel Matthias , Hagemann Stefan , Werner Christiane 
Published: November 2016

Summary

Ecosystem water‐use efficiency (WUE) is an important metric linking the global land carbon and water cycles. Eddy covariance‐based estimates of WUE in temperate/boreal forests have recently been found to show a strong and unexpected increase over the 1992–2010 period, which has been attributed to the effects of rising atmospheric CO2 concentrations on plant physiology.

To test this hypothesis, we forced the observed trend in the process‐based land surface model JSBACH by increasing the sensitivity of stomatal conductance (gs) to atmospheric CO2 concentration. We compared the simulated continental discharge, evapotranspiration (ET), and the seasonal CO2 exchange with observations across the extratropical northern hemisphere.

The increased simulated WUE led to substantial changes in surface hydrology at the continental scale, including a significant decrease in ET and a significant increase in continental runoff, both of which are inconsistent with large‐scale observations. The simulated seasonal amplitude of atmospheric CO2 decreased over time, in contrast to the observed upward trend across ground‐based measurement sites.

Our results provide strong indications that the recent, large‐scale WUE trend is considerably smaller than that estimated for these forest ecosystems. They emphasize the decreasing CO2 sensitivity of WUE with increasing scale, which affects the physiological interpretation of changes in ecosystem WUE.