bluuebunny/crossref_metadata_2025 huggingface dataset:
Subthreshold membrane responses underlying sparse spiking to natural vocal signals in auditory cortex
Authors: Perks Krista E. , Gentner Timothy Q.
Published: March 2015

Natural acoustic communication signals, such as speech, are typically high‐dimensional with a wide range of co‐varying spectro‐temporal features at multiple timescales. The synaptic and network mechanisms for encoding these complex signals are largely unknown. We are investigating these mechanisms in high‐level sensory regions of the songbird auditory forebrain, where single neurons show sparse, object‐selective spiking responses to conspecific songs. Using whole‐cell in vivo patch clamp techniques in the caudal mesopallium and the caudal nidopallium of starlings, we examine song‐driven subthreshold and spiking activity. We find that both the subthreshold and the spiking activity are reliable (i.e. the same song drives a similar response each time it is presented) and specific (i.e. responses to different songs are distinct). Surprisingly, however, the reliability and specificity of the subthreshold response was uniformly high regardless of when the cell spiked, even for song stimuli that drove no spikes. We conclude that despite a selective and sparse spiking response, high‐level auditory cortical neurons are under continuous, non‐selective, stimulus‐specific synaptic control. To investigate the role of local network inhibition in this synaptic control, we then recorded extracellularly while pharmacologically blocking local GABAergic transmission. This manipulation modulated the strength and the reliability of stimulus‐driven spiking, consistent with a role for local inhibition in regulating the reliability of network activity and the stimulus specificity of the subthreshold response in single cells. We discuss these results in the context of underlying computations that could generate sparse, stimulus‐selective spiking responses, and models for hierarchical pooling.
Mixed‐complexity artificial grammar learning in humans and macaque monkeys: evaluating learning strategies
Authors: Wilson Benjamin , Smith Kenny , Petkov Christopher I.
Published: March 2015

Artificial grammars (AG) can be used to generate rule‐based sequences of stimuli. Some of these can be used to investigate sequence‐processing computations in non‐human animals that might be related to, but not unique to, human language. Previous AG learning studies in non‐human animals have used different AGs to separately test for specific sequence‐processing abilities. However, given that natural language and certain animal communication systems (in particular, song) have multiple levels of complexity, mixed‐complexity AGs are needed to simultaneously evaluate sensitivity to the different features of the AG. Here, we tested humans and Rhesus macaques using a mixed‐complexity auditory AG, containing both adjacent (local) and non‐adjacent (longer‐distance) relationships. Following exposure to exemplary sequences generated by the AG, humans and macaques were individually tested with sequences that were either consistent with the AG or violated specific adjacent or non‐adjacent relationships. We observed a considerable level of cross‐species correspondence in the sensitivity of both humans and macaques to the adjacent AG relationships and to the statistical properties of the sequences. We found no significant sensitivity to the non‐adjacent AG relationships in the macaques. A subset of humans was sensitive to this non‐adjacent relationship, revealing interesting between‐ and within‐species differences in AG learning strategies. The results suggest that humans and macaques are largely comparably sensitive to the adjacent AG relationships and their statistical properties. However, in the presence of multiple cues to grammaticality, the non‐adjacent relationships are less salient to the macaques and many of the humans.
Aural localization of silent objects by active human biosonar: neural representations of virtual echo‐acoustic space
Authors: Wallmeier Ludwig , Kish Daniel , Wiegrebe Lutz , Flanagin Virginia L.
Published: March 2015

Some blind humans have developed the remarkable ability to detect and localize objects through the auditory analysis of self‐generated tongue clicks. These echolocation experts show a corresponding increase in ‘visual’ cortex activity when listening to echo‐acoustic sounds. Echolocation in real‐life settings involves multiple reflections as well as active sound production, neither of which has been systematically addressed. We developed a virtualization technique that allows participants to actively perform such biosonar tasks in virtual echo‐acoustic space during magnetic resonance imaging (MRI). Tongue clicks, emitted in the MRI scanner, are picked up by a microphone, convolved in real time with the binaural impulse responses of a virtual space, and presented via headphones as virtual echoes. In this manner, we investigated the brain activity during active echo‐acoustic localization tasks. Our data show that, in blind echolocation experts, activations in the calcarine cortex are dramatically enhanced when a single reflector is introduced into otherwise anechoic virtual space. A pattern‐classification analysis revealed that, in the blind, calcarine cortex activation patterns could discriminate left‐side from right‐side reflectors. This was found in both blind experts, but the effect was significant for only one of them. In sighted controls, ‘visual’ cortex activations were insignificant, but activation patterns in the planum temporale were sufficient to discriminate left‐side from right‐side reflectors. Our data suggest that blind and echolocation‐trained, sighted subjects may recruit different neural substrates for the same active‐echolocation task.
Auditory and visual cortex of primates: a comparison of two sensory systems
Authors: Rauschecker Josef P.
Published: March 2015

A comparative view of the brain, comparing related functions across species and sensory systems, offers a number of advantages. In particular, it allows separation of the formal purpose of a model structure from its implementation in specific brains. Models of auditory cortical processing can be conceived by analogy to the visual cortex, incorporating neural mechanisms that are found in both the visual and auditory systems. Examples of such canonical features at the columnar level are direction selectivity, size/bandwidth selectivity, and receptive fields with segregated vs. overlapping ON and OFF subregions. On a larger scale, parallel processing pathways have been envisioned that represent the two main facets of sensory perception: (i) identification of objects; and (ii) processing of space. Expanding this model in terms of sensorimotor integration and control offers an overarching view of cortical function independently of sensory modality.
The community ecology of pathogens: coinfection, coexistence and community composition
Authors: Seabloom Eric W. , Borer Elizabeth T. , Gross Kevin , Kendig Amy E. , Lacroix Christelle , Mitchell Charles E. , Mordecai Erin A. , Power Alison G.
Published: March 2015

Disease and community ecology share conceptual and theoretical lineages, and there has been a resurgence of interest in strengthening links between these fields. Building on recent syntheses focused on the effects of host community composition on single pathogen systems, we examine pathogen (microparasite) communities using a stochastic metacommunity model as a starting point to bridge community and disease ecology perspectives. Such models incorporate the effects of core community processes, such as ecological drift, selection and dispersal, but have not been extended to incorporate host–pathogen interactions, such as immunosuppression or synergistic mortality, that are central to disease ecology. We use a two‐pathogen susceptible‐infected (SI) model to fill these gaps in the metacommunity approach; however,SImodels can be intractable for examining species‐diverse, spatially structured systems. By placing disease into a framework developed for community ecology, our synthesis highlights areas ripe for progress, including a theoretical framework that incorporates host dynamics, spatial structuring and evolutionary processes, as well as the data needed to test the predictions of such a model. Our synthesis points the way for this framework and demonstrates that a deeper understanding of pathogen community dynamics will emerge from approaches working at the interface of disease and community ecology.
Epilepsy and deprivation, a data linkage study
Authors: Pickrell William O. , Lacey Arron S. , Bodger Owen G. , Demmler Joanne C. , Thomas Rhys H. , Lyons Ronan A. , Smith Phil E. M. , Rees Mark I. , Kerr Mike P.
Published: March 2015

Objective

To investigate whether the link between epilepsy and deprivation is due to factors associated with deprivation (social causation) or factors associated with a diagnosis of epilepsy (social drift).

Methods

We reviewed electronic primary health care records from 2004 to 2010, identifying prevalent and incident cases of epilepsy and recording linked deprivation scores. Logistic and Poisson regression models were used to calculate odds ratios and incidence rate ratios. The change in deprivation was measured 10 years after the initial diagnosis of epilepsy for a cohort of people.

Results

Between 2004 and 2010, 8.1 million patient‐years of records were reviewed. Epilepsy prevalence and incidence were significantly associated with deprivation. Epilepsy prevalence ranged from 1.13% (1.07–1.19%) in the most deprived decile to 0.49% (0.45–0.53%) in the least deprived decile (adjusted odds ratio 0.92, p < 0.001). Epilepsy incidence ranged from 40/100,000 per year in the most deprived decile to 19/100,000 per year in the least deprived decile (adjusted incidence rate ratio 0.94, p < 0.001). There was no statistically significant change in deprivation index decile 10 years after a new diagnosis of epilepsy (mean difference −0.04, p = 0.85).

Significance

Epilepsy prevalence and incidence are strongly associated with deprivation; the deprivation score remains unchanged 10 years after a diagnosis of epilepsy. These findings suggest that increasing rates of epilepsy in deprived areas are more likely explained by social causation than by social drift. The nature of the association between incident epilepsy and social deprivation needs further exploration.
The Red‐Fluorescing Marine Fish Tripterygion delaisi can Perceive its Own Red Fluorescent Colour
Authors: Kalb Nadine , Schneider Ralf F. , Sprenger Dennis , Michiels Nico K.
Published: March 2015

Many marine fishes show conspicuous red fluorescent body patterns. Recent work suggests that red fluorescence may be used as a visual colour cue in these species. Very few studies, however, have as yet been able to demonstrate that red fluorescent fish can actually perceive their own fluorescence. This is the first study to our knowledge in which a red fluorescent fish is trained to assess whether it can recognize red fluorescence. We used the triplefin Tripterygion delaisi, a species with conspicuous red fluorescent eye rings. Training and testing involved repeated binary choices between grey and red fluorescence cues. The training and testing were carried out under broad spectral illumination. The final testing phase involved cyan light illumination, mimicking natural ambient light at depth. When testing all nine combinations of three grey brightness levels against three red fluorescence brightness levels, individuals made significantly more correct choices than the random expectation under broad as well as cyan illumination. Under cyan illumination, fish trained on red chose the correct cue more often compared to fish trained on grey. An analysis of the effect of the brightness levels suggests that fish did indeed make their choices based on chromatic more than achromatic cues: The three grey levels did not affect the proportion of correct choices. We conclude that T. delaisi can perceive and respond to levels of fluorescence that are similar to its own. We also discuss the difficulties that can arise from using a binary choice design on a fish with a cryptobenthic lifestyle. We argue in favour of using sequential choice designs in future studies of T. delaisi.
Predicting a change in the order of spring phenology in temperate forests
Authors: Roberts Adrian M.I. , Tansey Christine , Smithers Richard J. , Phillimore Albert B.
Published: March 2015

The rise in spring temperatures over the past half‐century has led to advances in the phenology of many nontropical plants and animals. As species and populations differ in their phenological responses to temperature, an increase in temperatures has the potential to alter timing‐dependent species interactions. One species‐interaction that may be affected is the competition for light in deciduous forests, where early vernal species have a narrow window of opportunity for growth before late spring species cast shade. Here we consider the Marsham phenology time series of first leafing dates of thirteen tree species and flowering dates of one ground flora species, which spans two centuries. The exceptional length of this time series permits a rare comparison of the statistical support for parameter‐rich regression and mechanistic thermal sensitivity phenology models. While mechanistic models perform best in the majority of cases, both they and the regression models provide remarkably consistent insights into the relative sensitivity of each species to forcing and chilling effects. All species are sensitive to spring forcing, but we also find that vernal and northern European species are responsive to cold temperatures in the previous autumn. Whether this sensitivity reflects a chilling requirement or a delaying of dormancy remains to be tested. We then apply the models to projected future temperature data under a fossil fuel intensive emissions scenario and predict that while some species will advance substantially others will advance by less and may even be delayed due to a rise in autumn and winter temperatures. Considering the projected responses of all fourteen species, we anticipate a change in the order of spring events, which may lead to changes in competitive advantage for light with potential implications for the composition of temperate forests.
Spatial and topographic trends in forest expansion and biomass change, from regional to local scales
Authors: Buma Brian , Barrett Tara M.
Published: March 2015

Natural forest growth and expansion are important carbon sequestration processes globally. Climate change is likely to increase forest growth in some regions via CO2 fertilization, increased temperatures, and altered precipitation; however, altered disturbance regimes and climate stress (e.g. drought) will act to reduce carbon stocks in forests as well. Observations of asynchrony in forest change is useful in determining current trends in forest carbon stocks, both in terms of forest density (e.g. Mg ha−1) and spatially (extent and location). Monitoring change in natural (unmanaged) areas is particularly useful, as while afforestation and recovery from historic land use are currently large carbon sinks, the long‐term viability of those sinks depends on climate change and disturbance dynamics at their particular location. We utilize a large, unmanaged biome (>135 000 km2) which spans a broad latitudinal gradient to explore how variation in location affects forest density and spatial patterning: the forests of the North American temperate rainforests in Alaska, which store >2.8 Pg C in biomass and soil, equivalent to >8% of the C in contiguous US forests. We demonstrate that the regional biome is shifting; gains exceed losses and are located in different spatio‐topographic contexts. Forest gains are concentrated on northerly aspects, lower elevations, and higher latitudes, especially in sheltered areas, whereas loss is skewed toward southerly aspects and lower latitudes. Repeat plot‐scale biomass data (n = 759) indicate that within‐forest biomass gains outpace losses (live trees >12.7 cm diameter, 986 Gg yr−1) on gentler slopes and in higher latitudes. This work demonstrates that while temperate rainforest dynamics occur at fine spatial scales (<1000 m2), the net result of thousands of individual events is regionally patterned change. Correlations between the disturbance/establishment imbalance and biomass accumulation suggest the potential for relatively rapid biome shifts and biomass changes.
Dynamic transition of transcription and chromatin landscape during fission yeast adaptation to glucose starvation
Authors: Oda Arisa , Takemata Naomichi , Hirata Yoshito , Miyoshi Tomoichiro , Suzuki Yutaka , Sugano Sumio , Ohta Kunihiro
Published: March 2015

Shortage of glucose, the primary energy source for all organisms, is one of the most critical stresses influencing cell viability. Glucose starvation promptly induces changes in mRNA and noncoding RNA (ncRNA) transcription. We previously reported that glucose starvation induces long ncRNA (lncRNA) transcription in the 5′ segment of a fission yeast gluconeogenesis gene (fbp1+), which leads to stepwise chromatin alteration around the fbp1+ promoter and to subsequent robust gene activation. Here, we analyzed genomewide transcription by strand‐specific RNA sequencing, together with chromatin landscape by immunoprecipitation sequencing (ChIP‐seq). Clustering analysis showed that distinct mRNAs and ncRNAs are induced at the early, middle and later stages of cellular response to glucose starvation. The starvation‐induced transcription depends substantially on the stress‐responsive transcription factor Atf1. Using a new computer program that examines dynamic changes in expression patterns, we identified ncRNAs with similar behavior to the fbp1+ lncRNA. We confirmed that there are continuous lncRNAs associated with local reduction of histone density. Overlapping with the regions for transcription of these lncRNAs, antisense RNAs are antagonistically transcribed under glucose‐rich conditions. These results suggest that Atf1‐dependent integrated networks of mRNA and lncRNA govern drastic changes in cell physiology in response to glucose starvation.
Helicobacter pylori Eradication in Patients with Immune Thrombocytopenic Purpura: A Review and the Role of Biogeography
Authors: Frydman Galit H. , Davis Nick , Beck Paul L. , Fox James G.
Published: March 2015

Idiopathic thrombocytopenic purpura (ITP) is typically a diagnosis of exclusion, assigned by clinicians after ruling out other identifiable etiologies. Since a report by Gasbarrini et al. in 1998, an accumulating body of evidence has proposed a pathophysiological link between ITP and chronic Helicobacter pylori (H. pylori) infection. Clinical reports have described a spontaneous resolution of ITP symptoms in about 50% of chronic ITP patients following empirical treatment of H. pylori infection, but response appears to be geography dependent. Studies have also documented that ITP patients in East Asian countries are more likely to express positive antibody titers against H. pylori‐specific cytotoxic‐associated gene A (CagA), a virulence factor that is associated with an increased risk for gastric diseases including carcinoma. While a definitive mechanism by which H. pylori may induce thrombocytopenia remains elusive, proposed pathways include molecular mimicry of CagA by host autoantibodies against platelet surface glycoproteins, as well as perturbations in the phagocytic activity of monocytes. Traditional treatments of ITP have been largely empirical, involving the use of immunosuppressive agents and immunoglobulin therapy. However, based on the findings of clinical reports emerging over the past 20 years, health organizations around the world increasingly suggest the detection and eradication of H. pylori as a treatment for ITP. Elucidating the exact molecular mechanisms of platelet activation in H. pylori‐positive ITP patients, while considering biogeographical differences in response rates, could offer insight into how best to use clinical H. pylori eradication to treat ITP, but will require well‐designed studies to confirm the suggested causative relationship between bacterial infection and an autoimmune disease state.
Effect of chemical preservatives on shelf life of mushroom (Pleurotus ostreatus) cultivated on cassava peels
Authors: Olotu Ifeoluwa O. , Obadina Adewale O. , Sobukola Olajide P. , Adegunwa Mojisola , Adebowale Abdulrasaq A. , Kajihausa Esther , Sanni Lateef Oladimeji , Asagbra Yemisi , Ashiru Bolanle , Keith Tomlins
Published: March 2015

Short shelf life is a major impediment to the processing and distribution of mushroom. The effect of chemical preservatives on some quality attributes of mushroom during storage was investigated. Mushroom were soaked in four preservatives at two concentrations for 10 mins, packaged, stored at 4 °C for 30 days and analysed at intervals for their microbial population, colour, firmness and weight loss. Sodium benzoate (0.05%, 0.1%) lost its preservative effect on all the micro‐organisms enumerated after 3 days, and samples treated with 0.1% potassium sorbate had the lowest microbial load at the end of the storage period. Change in colour of the potassium sorbate (0.1%)‐treated sample was lower than and significantly different from the citric acid (2%, 4%)‐treated samples. The values of the firmness of the 4% citric acid preserved mushroom were significantly different (P ≤ 0.05) from other samples throughout the storage period. There was a significant negative correlation (r = −0.807, P < 0.01) between the firmness and weight loss of the preserved mushroom. Potassium sorbate (0.1%) and citric acid (4%) extended the shelf life of mushroom for 24 days.
Determination of quercetin in onion (Allium cepa) using β‐cyclodextrin‐coated CdSe/ZnS quantum dot‐based fluorescence spectroscopic technique
Authors: Dwiecki Krzysztof , Kwiatkowska Paulina , Siger Aleksander , Staniek Halina , Nogala‐Kałucka Małgorzata , Polewski Krzysztof
Published: March 2015

The aim of this work was to develop a CdSe/ZnS quantum dot ‐based fluorescence method for the determination of quercetin aglycone in onion. The synthesized nanostructures have been characterized by the use of spectroscopic techniques. The method developed is based on the formation of host–guest complexes between quercetin aglycone and β‐cyclodextrin and the consequent fluorescence quenching of the quantum dots. This allowed us to obtain a fast and selective spectroscopic method for the determination of this flavonoid. The developed technique enables determination of quercetin aglycone in real samples (methanolic extracts obtained from onion) in the presence of all components of the matrix, including quercetin glucosides and other phenolic compounds. The limit of detection was 14 μm and sensitivity was 13.2 nm. The accuracy of the method has been confirmed by HPLC measurements and the average recovery was in the 108–113% range, depending on the kind of sample tested.
Sleep quality, sleep duration and physical activity in obese adolescents: effects of exercise training
Authors: Mendelson M. , Borowik A. , Michallet A.‐S. , Perrin C. , Monneret D. , Faure P. , Levy P. , Pépin J.‐L. , Wuyam B. , Flore P.
Published: March 2015

Background

Decreased sleep duration and altered sleep quality are risk factors for obesity in youth. Structured exercise training has been shown to increase sleep duration and improve sleep quality.

Objectives

This study aimed at evaluating the impact of exercise training for improving sleep duration, sleep quality and physical activity in obese adolescents (OB).

Methods

Twenty OB (age: 14.5 ± 1.5 years; body mass index: 34.0 ± 4.7 kg m−2) and 20 healthy‐weight adolescents (HW) completed an overnight polysomnography and wore an accelerometer (SenseWear Bodymedia) for 7 days. OB participated in a 12‐week supervised exercise‐training programme consisting of 180 min of exercise weekly. Exercise training was a combination of aerobic exercise and resistance training.

Results

Sleep duration was greater in HW compared with OB (P < 0.05). OB presented higher apnoea‐hypopnoea index than HW (P < 0.05). Physical activity (average daily metabolic equivalent of tasks [METs]) by accelerometer was lower in OB (P < 0.05). After exercise training, obese adolescents increased their sleep duration (+64.4 min; effect size: 0.88; P = 0.025) and sleep efficiency (+7.6%; effect size: 0.76; P = 0.028). Physical activity levels were increased in OB as evidenced by increased steps per day and average daily METs (P < 0.05). Improved sleep duration was associated with improved average daily METs (r = 0.48, P = 0.04).

Conclusion

The present study confirms altered sleep duration and quality in OB. Exercise training improves sleep duration, sleep quality and physical activity.
Ten‐year beverage intake trends among US preschool children: rapid declines between 2003 and 2010 but stagnancy in recent years
Authors: Ford C. N. , Ng S. W. , Popkin B. M.
Published: March 2015

Background

It has been previously reported that total energy intake among US preschool children (ages 2–5 years) decreased between 2003–2004 and 2009–2010. However, little is known about how intakes of beverages among US preschoolers (ages 2–5 years) changed from 2003–2004 to 2011–2012.

Objectives

This paper examines changes in intakes of key beverages during this period, as well as how eating location (at home or away from home) and source (store vs. others) may have contributed to these changes.

Methods

Cross‐sectional day one dietary data among children ages 2–5 years from the National Health and Nutrition Examination Survey 2003–2004, 2005–2006, 2007–2008, 2009–2010 and 2011–2012 were used. Survey‐weighted mean intakes by survey year, eating location and source were computed for total sugar‐sweetened beverages (SSBs), milks, 100% juice, low/no‐calorie beverages, 10 key beverages, total beverages and total foods. Means were compared using two‐tailed z‐tests with Bonferroni corrections (α < 0.05).

Results

Between 2003–2004 and 2011–2012, among 2–5 year olds, total caloric intake fell by 132 kcal d−1, with intakes of beverages falling by 55 kcal d−1. Decreases in intakes of total SSBs (−57 kcal d−1), fruit‐flavoured or juice drinks containing <100% juice (juice drinks) (−37 kcal d−1), caloric soft drinks (−13 kcal d−1) and >1% fat, low‐sugar milk (−42 kcal d−1) were among the major changes. By eating location, total beverage intake at home fell by 73 kcal d−1. By source, total beverage intake from stores fell by 106 kcal d−1. Changes in intakes occurred primarily between 2003–2004 and 2009–2010, as there were no significant differences in beverage intakes between 2009–2010 and 2011–2012. Intakes of total calories (+49 kcal d−1) and calories from foods (+53 kcal d−1) trended upward between 2009–2010 and 2011–2012, but changes were not significant.

Conclusions

These findings suggest improvements in the diets of preschoolers between 2003–2004 and 2009–2010, of which stores were a major contributor.
Compassionate access anti‐tumour necrosis factor‐α therapy for ulcerative colitis in Australia: the benefits to patients
Authors: Costello S. P. , Ghaly S. , Beswick L. , Pudipeddi A. , Agarwal A. , Sechi A. , O'Connor S. , Connor S. J. , Sparrow M. P. , Bampton P. , Walsh A. J. , Andrews J. M. ,   Australian Inflammatory Bowel Disease Association (AIBDA)
Published: March 2015

Background

The efficacy of infliximab has been demonstrated in patients with both acute severe and moderate‐severe ulcerative colitis (UC). However, there is a need for ‘real‐life data’ to ensure that conclusions from trial settings are applicable in usual care. We therefore examined the national experience of anti‐tumour necrosis factor‐α (TNF‐α) therapy in UC.

Methods

Case notes review of patients with UC who had received compassionate access (CA) anti‐TNF‐α therapy from prospectively maintained inflammatory bowel disease databases of six Australian adult teaching hospitals.

Results

Patients either received drug for acute severe UC (ASUC) failing steroids (n = 29) or for medically refractory UC (MRUC) (n = 35). In ASUC, the treating physicians judged that anti‐TNF‐α therapy was successful in 20/29 patients (69%); in these cases, anti‐TNF‐α was able to be discontinued (after 1–3 infusions in 19/20 responders) as clinical remission was achieved. Consistent with this perceived benefit, only 7/29 (24%) subsequently underwent colectomy during a median follow up of 12 months (interquartile range (IQR) 5–16). Eight of the 35 patients with MRUC (23%) required colectomy during a median follow up of 28 months (IQR 11–43). The majority of these patients (20/35 or 57%) had anti‐TNF‐α therapy for ≥4 months, whereas, 27/29 (93%) of ASUC patients had CA for ≤3 months.

Conclusions

These data show an excellent overall benefit for anti‐TNF‐α therapy in both ASUC and MRUC. In particular, only short‐duration anti‐TNF‐α was required in ASUC. These real‐life data thus support the clinical trial data and should lead to broader use of this therapy in UC.
Trends in the prevalence of erosive tooth wear in Brazilian preschool children
Authors: Murakami Christiana , Tello Gustavo , Abanto Jenny , Oliveira Luciana Butini , Bonini Gabriela Cunha , Bönecker Marcelo
Published: March 2015

Objectives

To report trends in the prevalence of ETW in Brazilian preschool children.

Methods

Three cross‐sectional surveys were carried out on boys and girls aged 3–4 years living in Diadema, in the years 2008, 2010 and 2012 following the same criteria and methodology. A total of 2801 children were systematically examined during a National Day of Children's vaccination. Examiners were trained and calibrated to diagnose ETW using a modified version of the O'Brien index.

Results

The prevalence of ETW was 51.6% (95% CI 48.4–55.0) in 2008, 53.9% (95% CI 50.7–57.0) in 2010 and 51.3% (95% CI 47.8–54.7) in 2012. There was no significant association between prevalence of ETW from 2008 to 2012 (χ2 for trend: P = 0.92). There was no significant association in the severity of ETW during this study's period. Most lesions were confined to enamel in all three studies.

Conclusions

A high prevalence of ETW was found in this sample of preschool children in 2008, 2010 and 2012. No trends of increase or decrease in the prevalence and severity of ETW during this study's period.
MHC Class II Gene Silencing in Trophoblast Cells Is Caused by Inhibition of CIITA Expression
Authors: MORRIS ANN C. , RILEY JAMES L. , FLEMING WILLIAM H. , BOSS JEREMY M.
Published: March 2015

PROBLEM: Major histocompatibility complex (MHC) class II molecule expression is specifically suppressed on fetal trophoblasts, even in response to interferon (IFN)‐γ, a potent inducer of MHC class II genes. The suppression of class II induction has been suggested to play a role in preventing rejection of the fetal allograft. The mechanism of this suppression is unknown.

METHOD OF STUDY: Human trophoblast cell lines were examined for expression of MHC class II transcription factors and for activity of the IFN‐γ signaling pathway. Additionally, trophoblast cells were transfected with a vector expressing the class II transactivator, CIITA, and assayed for class II expression.

RESULTS: The MHC class II transcription factors RFX and X2BP and the IFN‐γ signaling pathway components are expressed constitutively and are functional in trophoblasts. However, CIITA expression was absent in trophoblasts and could not be induced by IFN‐γ. Transfection of CIITA into trophoblast cells resulted in derepression of class II gene expression.

CONCLUSIONS: The lack of induction of MHC class II genes in response to IFN‐γ in trophoblast cells is caused neither by the absence of factors that bind class II promoters, nor by a lesion in the IFN‐γ signaling pathway, but results from a specific inhibition of the CIITA gene.
Presence of Four Tissue Inhibitors of Matrix Metalloproteinases (TIMP‐1, −2, −3 and −4) in Human Fetal Membranes
Authors: FORTUNATO STEPHEN J. , MENON RAMKUMAR , LOMBARDI SALVATORE J.
Published: March 2015

PROBLEM: Matrix metalloproteinases play a critical role in fetal membrane extracellular matrix (ECM) homeostasis. Remodeling of the ECM during normal placental development is a balanced activity between various matrix metalloproteinases and their tissue‐specific counter‐ regulatory proteins (tissue inhibitors of matrix metalloproteinases [TIMPs]). We have reported the presence of TIMP‐1 and TIMP‐2 in placental membranes in culture. In this study we have investigated the membrane expression of TIMP‐1 and TIMP‐2 during labor and nonlabor conditions and also the presence of two novel TIMP family members (TIMP‐3 and TIMP‐4).

METHOD OF STUDY: Amniochorionic membranes collected from women undergoing Cesarean section and were cultured in an organ explant system. Membranes were also collected from laboring women after vaginal delivery. Samples were subjected to reverse transcriptase‐polymerase chain reaction (RT‐PCR) using primers specific for TIMP‐1, TIMP‐2, TIMP‐3, and TIMP‐4. Localization of TIMP mRNAs was accomplished by in situ hybridization, and peptides were localized by immunocytochemistry.

RESULTS: RT‐PCR data demonstrated the expression of all the TIMPs in tissues from laboring and nonlaboring women as well as in cultured membranes. TIMP‐4 expression was seen in RT‐PCR, however, only a faint band was visible in all the tissues tested. In situ hybridization localized the TIMP mRNAs to the amnion, chorion, and to scattered cells in the connective tissue.

CONCLUSION: Human fetal membrane cells (amniochorion and decidua) express mRNA for all the TIMPs studied so far.
An In Vitro Microassay to Assess the Ability of Plasmodium falciparum—Infected Erythrocytes to Bind to the Human Syncytiotrophoblast
Authors: MAUBERT BERTRAND , RICHE DOMINIQUE , DELORON PHILIPPE
Published: March 2015

PROBLEM: Erythrocytes parasitized by matures stages of Plasmodium falciparum are frequently sequestered in human placenta. The consequences of this sequestration have been well described, but little is known about the mechanisms used by the parasite to concentrate in the placenta.

METHOD OF STUDY: We developed an in vitro assay to study their binding capacity to the human syncytiotrophoblast. Our cytoadherence test was scaled down, and each step of the assay was optimized to enhance the sensitivity of our model.

RESULTS: Cytoadherence assays between P. falciparum‐infected erythrocytes and human trophoblasts are easily performed using low numbers of trophoblast cells. The process can also be used to carry out immunofluorescence and immunostaining techniques.

CONCLUSIONS: The test may be adapted to any kind of cell, is inexpensive, and allows the culture of virtually any kind of cell for several weeks.
Correlation Between β2‐Glycoprotein Antibodies and Antiphospholipid Antibodies in Patients with Reproductive Failure
Authors: CHONG PENNY , MATZNER WILLIAM , CHING WENDELL
Published: March 2015

PROBLEM: Antiphospholipid antibodies (APAs) are important in the etiology of reproductive failure. Studies have shown that binding proteins are necessary for the detection of APAs. One of these, β2‐glycoprotein, has been shown to be necessary for detection of anticardiolipin antibodies. It is felt that some APAs may be directed to the binding protein itself, or to a combination of the binding protein and phospholipid.

METHOD OF STUDY: In this study, a comparison of APAs vs. anti β2‐glycoprotein antibodies was performed on the sera of 123 women younger than 40 years of age with a history of reproductive failure. Antibodies to six phospholipid epitopes, cardiolipin, phosphatidyle‐thanolamine, phosphatidylserine, phosphatidylinositol, phosphatidic acid, phosphatidylglycerol, and phosphatidylserine, were measured.

RESULTS: Of the 123 women tested, 33 had one or more positive immunoglobulin (Ig)G antibodies to phospholipids, of which 9 were to cardiolipin. However, only 1 of 123 women had IgG antibodies to β2‐glycoprotein and she was APA negative. Thirty‐eight of 123 women had one or more IgM antibodies to phospholipids, with none directed to cardiolipin IgM. In contrast, only 8 of the 123 women had IgM antibodies to β2‐glycoprotein. Five of the eight patients had IgM APA; 4 of 5 had IgM antibodies to PE, 1 to PI.

CONCLUSIONS: There is no correlation between β2‐glycoprotein antibodies and APA status in this population. To date, our most sensitive test for detecting phospholipid autoimmune‐mediated in vitro fertilization failure still appears to be the ELISA assay for APA.
T helper‐2 Type of Interleukins with De Novo Germinal Center Formation in the Spleen During Murine Pregnancy
Authors: HEGDE UMASHASHI C. , NAINAN RACHEL
Published: March 2015

PROBLEM: Murine pregnancy is characterized by transient thymic atrophy and splenomegaly. Although some reports on the thymus are available, little is known about the role of the spleen. In the present study, sequential changes in the spleen have been evaluated during murine syngeneic pregnancy.

METHOD OF STUDY: Formation of germinal centers (GCs), immunoglobulin positive (Ig+) cells and interleukin (IL)‐2, IL‐4, and IL‐6 were immunolocalized in the spleen during pregnancy and compared with a control group of virgin mice.

RESULTS: Initiation of T‐cell dependent B‐cell response with the induction of peanut agglutinin (PNA+) GCs correlated with decrease in IL‐2 and maintenance of IL‐4 and IL‐6 on day‐1 pregnancy followed by an increase in Ig+ cells.

CONCLUSION: The immune response observed in the syngeneically pregnant mother is not directed to paternal major histocompatibility complex antigens. Present studies demonstrate for the first time the role of the spleen in initiating a T‐cell dependent B‐cell response with a shift of systemic immune response from T helper 1 to T helper 2 type.
TNF‐α Expression in Embryos Exposed to a Teratogen
Authors: IVNITSKY IRENA , TORCHINSKY ARKADY , GORIVODSKY MARAT , ZEMLIAK ILONA , ORENSTEIN HASIDA , SAVION SHOSHANA , SHEPSHELOVICH JEANE , CARP HOWARD , FEIN AMOS , TODER VLADIMIR
Published: March 2015

PROBLEM: The role of tumor necrosis factor (TNF)‐α produced by embryonic cells in normal and abnormal development is poorly understood. To assess to what extent TNF‐α may be involved in the process of induced dysmorphogenesis, the expression of TNF‐α and TNF‐α receptor (TNFRI) mRNA as well as TNF‐α protein was evaluated in embryos responding to a cyclophosphamide (CP)‐induced teratogenic insult. The effect of maternal immunostimulation increasing the embryo's tolerance to CP on TNF‐α expression was also investigated.

METHOD OF STUDY: ICR female mice were treated intraperitoneally with 40 mg/kg CP on day 12 of pregnancy. The immunostimulator, xenogeneic rat splenocytes, was injected intrauterine 21 days before mating. Embryos were collected on days 13, 14, or 15 of pregnancy. TNF‐α mRNA, TNFRI mRNA, and TNF‐α protein expression were evaluated by in situ hybridization and immunostaining techniques in control, teratogen‐treated, and immuno‐stimulated teratogen‐treated embryos.

RESULTS: CP‐treated embryos showed severe external brain and craniofacial anomalies already visible on day 14 of pregnancy. TNF‐α mRNA transcripts were detected in cells of the brain and the head of 13‐day embryos, which preceded the occurrence of CP‐induced external craniofacial anomalies. On day 15 of pregnancy, when severe craniofacial anomalies increased, a significant increase in the intensity of TNF‐α, TNFR1 mRNA transcripts, and TNF‐α protein expression were observed in cells of the malformed regions of the head and the brain. In other nonmalformed organs of CP‐treated embryos such as the liver (not macroscopically different from controls), neither TNF‐α nor TNFR1 transcripts were detected. Immunostimulation substantially diminished the severity of CP‐induced brain and craniofacial anomalies, decreased the resorption rate, and was associated with decreased intensity of TNF‐α mRNA transcripts detected on day 15 of pregnancy in the head and the brain of CP‐treated embryos.

CONCLUSIONS: TNF‐α expressed in the embryo may be one of the molecules promoting the formation of CP‐induced brain and craniofacial anomalies. The decrease of TNF‐α expression in embryos of immunostimulated females may be one of the mechanisms responsible for the increased tolerance to the teratogenic insult.
An Exploratory Investigation of the Role of Parenting Stress in Relationship Focused Intervention
Authors: Alquraini Turki , Mahoney Gerald
Published: March 2015

Background

Mothers of young children with Pervasive Developmental Disorders (PDD) and other disabilities (DD) have been reported to experience high levels of stress. This investigation examined the effects of parental stress on mothers? participation in a Relationship Focused intervention (RFI).

Methods

Mothers and young children who had either PDD (n = 18) or DD (n = 26) received weekly RF intervention for one year.

Results

Pre‐post comparisons indicated significant increases in mothers? responsiveness and children?s development and social emotional functioning. Intervention effects were greater for mothers of children with PDD than for mothers of children with DD. There were three findings related to the role parenting stress. First, high levels of parenting stress did not interfere with mothers? ability to learn RFI strategies; second, there were non‐significant decreases in parenting stress during intervention; third, parenting stress enhanced the effects of mothers? responsiveness on children.

Conclusion

High levels of parenting stress does not appear to interfere with parent participation in RFI.
Assessment of bagging GBLUP for whole‐genome prediction of broiler chicken traits
Authors: Abdollahi‐Arpanahi R. , Morota G. , Valente B.D. , Kranis A. , Rosa G.J.M. , Gianola D.
Published: March 2015

Bootstrap aggregation (bagging) is a resampling method known to produce more accurate predictions when predictors are unstable or when the number of markers is much larger than sample size, because of variance reduction capabilities. The purpose of this study was to compare genomic best linear unbiased prediction (GBLUP) with bootstrap aggregated sampling GBLUP (Bagged GBLUP, or BGBLUP) in terms of prediction accuracy. We used a 600 K Affymetrix platform with 1351 birds genotyped and phenotyped for three traits in broiler chickens; body weight, ultrasound measurement of breast muscle and hen house egg production. The predictive performance of GBLUP versus BGBLUP was evaluated in different scenarios consisting of including or excluding the TOP 20 markers from a standard genome‐wide association study (GWAS) as fixed effects in the GBLUP model, and varying training sample sizes and allelic frequency bins. Predictive performance was assessed via five replications of a threefold cross‐validation using the correlation between observed and predicted values, and prediction mean‐squared error. GBLUP overfitted the training set data, and BGBLUP delivered a better predictive ability in testing sets. Treating the TOP 20 markers from the GWAS into the model as fixed effects improved prediction accuracy and added advantages to BGBLUP over GBLUP. The performance of GBLUP and BGBLUP at different allele frequency bins and training sample sizes was similar. In general, results of this study confirm that BGBLUP can be valuable for enhancing genome‐enabled prediction of complex traits.
Random regression test day models to estimate genetic parameters for milk yield and milk components in Philippine dairy buffaloes
Authors: Flores E.B. , van der Werf J.
Published: March 2015

Heritabilities and genetic correlations for milk production traits were estimated from first‐parity test day records on 1022 Philippine dairy buffalo cows. Traits analysed included milk (MY), fat (FY) and protein (PY) yields, and fat (Fat%) and protein (Prot%) concentrations. Varying orders of Legendre polynomials (Legm) as well as the Wilmink function (Wil) were used in random regression models. These various models were compared based on log likelihood, Akaike's information criterion, Bayesian information criterion and genetic variance estimates. Six residual variance classes were sufficient for MY, FY, PY and Fat%, while seven residual classes for Prot%. Multivariate analysis gave higher estimates of genetic variance and heritability compared with univariate analysis for all traits. Heritability estimates ranged from 0.25 to 0.44, 0.13 to 0.31 and 0.21 to 0.36 for MY, FY and PY, respectively. Wilmink's function was the better fitting function for additive genetic effects for all traits. It was also the preferred function for permanent environment effects for Fat% and Prot%, but for MY, FY and PY, the Legm was the appropriate function. Genetic correlations of MY with FY and PY were high and they were moderately negative with Fat% and Prot%. To prevent deterioration in Fat% and Prot% and improve milk quality, more weight should be applied to milk component traits.
Genetic analyses of rafted macroalgae reveal regional oceanographic connectivity patterns
Authors: Bussolini Laura T. , Waters Jonathan M.
Published: March 2015

Aim

This study examines beach‐cast rafts of Durvillaea antarctica (bull kelp) along New Zealand's east coast to determine spatial variation in beach‐cast haplotype assemblages. By using genetic markers, the geographical origins of rafted D. antarctica samples can be determined, allowing for the examination of dispersal pathways, distances rafted, and potential barriers to dispersal.

Location

An approximately 1000 km stretch of New Zealand's eastern coastline.

Methods

686 samples of beach‐cast D. antarctica rafts were collected and sequenced for cytochrome c oxidase subunit 1 in order to infer geographical origins and dispersal dynamics of rafted specimens. Results were examined using principal components analysis (PCA) in order to determine spatial groupings. Analysis of molecular variance (AMOVA) was used to determine statistical support for the detected spatial groups.

Results

Hierarchical AMOVA revealed three major regional genetic assemblages, which probably reflect broad oceanographic features. In particular, the north–south genetic partitioning in rafted kelp assemblages either side of the Cape Campbell region in central New Zealand closely corresponds to an oceanographically mediated disjunction previously observed in a number of larval‐dispersed marine invertebrate taxa.

Main conclusions

Findings from this study suggest that passively drifting kelp rafts and planktonic invertebrate larvae may be similarly constrained by oceanographic features, and demonstrate how the phylogenetic structure present in populations of D. antarctica provide a framework with which to map dispersal patterns.