Storm pulse responses of fluvial organic carbon to seasonal source supply and transport controls in a midwestern agricultural watershed.

Storm events are the primary mechanisms of delivering fluvial organic carbon (OC) in both dissolved (DOC) and particulate (POC) forms but their sources and flow pathways can vary with seasonal land use and weather. Within the low relief and poorly drained landscapes of a predominantly agricultural watershed in Eastern Iowa, six storm events were monitored for DOC and POC concentrations over a two hydrological year period in order to investigate the export mechanisms, landscape connectivity, and hydro-climatological controls of fluvial OC under representative events and associated management practices. Event-driven dynamics favored POC over DOC, where POC accounted for 54-94 % of total OC export during events, highlighting a sampling-driven bias against POC in the absence of event monitoring. The disparity between POC and DOC export exhibited a seasonal effect, where the POC:DOC export ratio was low (1.3-1.7) for October events while June/July events yielded a much higher value (up to a value of 14.7). The relationships between event DOC and POC export, Normalized Difference Vegetation Index of landscapes, and antecedent wetness conditions suggest a strong interaction or competing influences between vegetation coverage and runoff-generation threshold. While we recognize the low statistical power of the limited data set (n = 6), the storm events could be binned into two clusters: a "bare soil" period and a crop "rapid growth" period. Specifically, intra-storm variations in OC concentration and concentration-discharge (C-Q) hysteresis patterns demonstrated a seasonally-dependent access to contributing OC sources, which can be viewed as the rapid liberation of DOC during the "bare soil" period, and a progressive leaching of terrestrial DOC during the "rapid growth" period. Although high resolution event monitoring of fluvial carbon is rare this work highlights the importance of such efforts to predict C sourcing and transformation in inland water systems under variable land use and across seasons.

Genomic innovations, transcriptional plasticity and gene loss underlying the evolution and divergence of two highly polyphagous and invasive Helicoverpa pest species.

BACKGROUND: Helicoverpa armigera and Helicoverpa zea are major caterpillar pests of Old and New World agriculture, respectively. Both, particularly H. armigera, are extremely polyphagous, and H. armigera has developed resistance to many insecticides. Here we use comparative genomics, transcriptomics and resequencing to elucidate the genetic basis for their properties as pests. RESULTS: We find that, prior to their divergence about 1.5 Mya, the H. armigera/H. zea lineage had accumulated up to more than 100 more members of specific detoxification and digestion gene families and more than 100 extra gustatory receptor genes, compared to other lepidopterans with narrower host ranges. The two genomes remain very similar in gene content and order, but H. armigera is more polymorphic overall, and H. zea has lost several detoxification genes, as well as about 50 gustatory receptor genes. It also lacks certain genes and alleles conferring insecticide resistance found in H. armigera. Non-synonymous sites in the expanded gene families above are rapidly diverging, both between paralogues and between orthologues in the two species. Whole genome transcriptomic analyses of H. armigera larvae show widely divergent responses to different host plants, including responses among many of the duplicated detoxification and digestion genes. CONCLUSIONS: The extreme polyphagy of the two heliothines is associated with extensive amplification and neofunctionalisation of genes involved in host finding and use, coupled with versatile transcriptional responses on different hosts. H. armigera's invasion of the Americas in recent years means that hybridisation could generate populations that are both locally adapted and insecticide resistant.

Modular Patterns of Phase Desynchronization Networks During a Simple Visuomotor Task.

By performing sensor-level analysis on magnetoencephalography (MEG) data we identified the dynamic evolution of the functional connectivity networks during a simple visuomotor task. The functional connectivity networks were constructed using the concept of phase-locking value (PLV). We illustrate that the task-related activity is mediated by distinct complex networks related to the PLV desynchronization that configure their architecture dynamically during the task. These networks are prominent at ß and α band, and are characterized by coherent modular organization. Moreover the time for the development of the desynchronization networks at α band predicts the intra-subject variability of reaction time. Thus, the spatio-temporal dynamics and the structural properties of the emerged functional networks share common characteristics with the mechanism of coactivation and resting state networks.

OfftargetFinder: a web tool for species-specific RNAi design.

MOTIVATION: RNA interference (RNAi) technology is being developed as a weapon for pest insect control. To maximize the specificity that such an approach affords we have developed a bioinformatic web tool that searches the ever-growing arthropod transcriptome databases so that pest-specific RNAi sequences can be identified. This will help technology developers finesse the design of RNAi sequences and suggests which non-target species should be assessed in the risk assessment process. AVAILABILITY AND IMPLEMENTATION: http://rnai.specifly.org CONTACT: crobin@unimelb.edu.au.

Chemosensory receptor genes in the Oriental tobacco budworm Helicoverpa assulta.

The Oriental tobacco budworm (Helicoverpa assulta) is a specialist herbivore moth and its larvae feed on Solanaceous plants. (Z)-9-hexadecenal (Z9-16: Ald) is the major sex pheromone component in H. assulta but the specific pheromone receptor (PR) against Z9-16: Ald has not yet been identified. In the present study, we integrated transcriptomic, bioinformatic and functional characterization approaches to investigate the chemosensory receptor genes of H. assulta. We identified seven potential PRs with 44 olfactory receptors, 18 gustatory receptors and 24 ionotropic receptors, which were further studied by in silico gene expression profile, phylogenetic analysis, reverse transcription PCR and calcium imaging assays. The candidate PR, HassOR13, showed a strong response to the minor sex pheromone component, (Z)-11-hexadecenal, but not the major component, Z9-16: Ald, in calcium imaging assays. This study provides the molecular basis for comparative studies of chemosensory receptors between H. assulta and other Helicoverpa species and will advance our understanding of the evolution and function of Lepidoptera insect chemosensation.

Altered temporal correlations in resting-state connectivity fluctuations in children with reading difficulties detected via MEG.

In this study we investigate systematic patterns of rapidly changing sensor-level interdependencies in resting MEG data obtained from 23 children experiencing reading difficulties (RD) and 27 non-impaired readers (NI). Three-minute MEG time series were band-passed and subjected to blind source separation (BSS) prior to estimating sensor interdependencies using the weighted phase synchronization measure (wPLI). Dynamic sensor-level network properties were then derived for two network metrics (global and local efficiency). The temporal decay of long-range temporal correlations in network metrics (LRTC) was quantified using the scaling exponent (SE) in detrended fluctuation analysis (DFA) plots. Having established the reliability of SE estimates as robust descriptors of network dynamics, we found that RD students displayed significantly reduced (a) overall sensor-level network organization across all frequency bands (global efficiency), and (b) temporal correlations between sensors covering the left temporoparietal region and the remaining sensors in the ß3 band (local efficiency). Importantly, both groups displayed scale-free global network connectivity dynamics. The direct application of DFA to MEG signals failed to reveal significant group differences. Results are discussed in relation to prior evidence for disrupted temporoparietal functional circuits for reading in developmental reading disability.

Hormonal replacement therapy in ovarian cancer survivors: a survey among Greek gynecologists.

PURPOSE OF INVESTIGATION: In this survey we evaluated the prescription attitude of Greek gynecologists towards hormone replacement therapy (HRT) for ovarian cancer survivors. METHODS: An anonymous questionnaire was sent to 900 members of the Hellenic Society of Obstetrics and Gynecology presenting a hypothetical case of an ovarian cancer survivor with indications for HRT followed by a series of relevant questions. RESULTS: Two hundred and ninety-eight responses were analyzed with regards to age, gender and practice setting. HRT would be prescribed by 48% of Greek gynecologists; regarding type of regimen, 60% would prescribe tibolone, 19% estrogen alone and 21% estrogen plus progestagen. In contrast, 52% of Greek gynecologists would not prescribe HRT due to the fear of ovarian cancer relapse (83%), or the development of breast cancer (6%), or both cancers (9%); among them, 21% would alternatively prescribe CNS medications, 9% SERMs, phyto-estrogens or bisphosphonates, while the remaining 70% would not prescribe anything. CONCLUSIONS: One out of two Greek gynecologists would prescribe HRT in ovarian cancer survivors. An alternative therapy, mainly CNS medications, would be suggested by 21% of the opposers.

A prospective randomized study for evaluation of wound retractors in the prevention of incision site infections after cesarean section.

Surgical site infections (SSIs) after cesarean section appear to be more common than generally believed. We prospectively evaluated 231 consecutive pregnant women who underwent elective or emergency cesarean section, and were assigned to have either the Alexis wound retractor (study group) or a conventional Doyen retractor (control group) during the operation. There was no evidence of SSI, defined as wound dehiscence, pain or tenderness in the lower abdomen, localized swelling, redness, heat or purulent discharge from the wound in any woman in the study group. Moreover, no endometritis occurred in this patient collective. There were three SSI in the control group, but no endometritis. Our preliminary data show excellent protection of wound infections with an additive protective effect to that given by antibiotic cover. After a short learning curve, the handling of the Alexis device became easier and the median insertion time was 18 sec.

A non-catecholamine-producing sympathetic paraganglioma of the spermatic cord: the importance of performing candidate gene mutation analysis.

BACKGROUND: Catecholamine-producing tumours are called pheochromocytomas when they are located in the adrenal gland and sympathetic paragangliomas when they are located elsewhere in the abdomen. Rarely these tumours do not produce catecholamines and even more rarely they arise in the spermatic cord. Over the past decade, systematic mutation analysis of apparently sporadic cases of pheochromocytomas and paragangliomas has elucidated the frequent presence of germ line mutations in one of five candidate genes, including RET, VHL, SDHB, SDHC, and SDHD. CLINICAL HISTORY AND METHODS: We describe a 45-year-old man with a non catecholamine-producing paraganglioma of the spermatic cord. We performed SDHB immunohistochemistry and performed mutation analysis of the SDHB, SDHC, and SDHD genes. RESULTS: There was no staining of tumour cells with SDHB immunohistochemistry, indicative of an SDH mutation. Mutation analysis demonstrated a germ line SDHD mutation (p.Val147Met). CONCLUSIONS: Systematic mutation analysis is required in paraganglioma patients for the detection of germ line mutations. This should be preceded by SDHB immunohistochemistry to limit the number of genes to be tested.

ERBB2 (HER2) protein expression in uterine sarcomas.

PURPOSE: Multiple clinical trials in recent years have shown that breast cancer patients with primary tumors overexpressing ERBB2 can be effectively treated with specific forms of modern anti-ERBB2-targeted therapy. The aim of the present study was to analyze the expression of the ERBB2 (HER2) protein in uterine sarcomas, in order to investigate the possibility of applying this treatment modality in uterine sarcomas. METHODS: The expression of ERBB2 has been analyzed immunohistochemically in formalin-fixed paraffin-embedded primary uterine sarcomas (n = 11). RESULTS: Using a semi-quantitative immunohistochemical score, we found that ERBB2 expression was very weak in the majority of tumors, with only three sarcomas showing moderate ERBB2 expression. Published studies evaluating the same issue in small numbers of uterine sarcomas reached similar findings. CONCLUSION: Overall, ERBB2 expression appears to be weak in uterine sarcomas. However, targeted treatment might still be feasible in a subgroup of patients with uterine sarcomas overexpressing ERBB2.

Mucocele of the appendix mimicking an adnexal mass: a case report.

Mucocele of the appendix is a rare entity usually mimicking an adnexal tumour. There is no specific imaging or screening method to determine the diagnosis with certainty preoperatively. Appendiceal malignancy can be the underlying cause, although it is not common. We present a case of an appendiceal mucocele mimicking an ovarian tumour by both clinical and imaging (TVS and MRI) methods. This pathological condition should be considered by all the gynaecologists in the differential diagnosis of a right-sided pelvic mass.

Vaginal wall fibroid.

Localization of leiomyomas in the vaginal wall is very rare. We report about a case of a vaginal leiomyoma in the anterior vaginal wall, preoperatively identified with sonography and CT. Surgical enucleation was performed. Surgical removal in these cases is safe and usually with minimal bleeding.

Butterfly genomics eclosing.

Technological and conceptual advances of the last decade have led to an explosion of genomic data and the emergence of new research avenues. Evolutionary and ecological functional genomics, with its focus on the genes that affect ecological success and adaptation in natural populations, benefits immensely from a phylogenetically widespread sampling of biological patterns and processes. Among those organisms outside established model systems, butterflies offer exceptional opportunities for multidisciplinary research on the processes generating and maintaining variation in ecologically relevant traits. Here we highlight research on wing color pattern variation in two groups of Nymphalid butterflies, the African species Bicyclus anynana (subfamily Satyrinae) and species of the South American genus Heliconius (subfamily Heliconiinae), which are emerging as important systems for studying the nature and origins of functional diversity. Growing genomic resources including genomic and cDNA libraries, dense genetic maps, high-density gene arrays, and genetic transformation techniques are extending current gene mapping and expression profiling analysis and enabling the next generation of research questions linking genes, development, form, and fitness. Efforts to develop such resources in Bicyclus and Heliconius underscore the general challenges facing the larger research community and highlight the need for a community-wide effort to extend ongoing functional genomic research on butterflies.

Language dysfunction after stroke and damage to white matter tracts evaluated using diffusion tensor imaging.

BACKGROUND AND PURPOSE: Knowledge of the anatomic basis of aphasia after stroke has both theoretic and clinical implications by informing models of cortical connectivity and providing data for diagnosis and prognosis. In this study we use diffusion tensor imaging to address the relationship between damage to specific white matter tracts and linguistic deficits after left hemisphere stroke. MATERIALS AND METHODS: Twenty patients aged 38-77 years with a history of stroke in the left hemisphere underwent diffusion tensor imaging, structural MR imaging, and language testing. All of the patients were premorbidly right handed and underwent imaging and language testing at least 1 month after stroke. RESULTS: Lower fractional anisotropy (FA) values in the superior longitudinal and arcuate fasciculi of the left hemisphere, an indication of greater damage to these tracts, were correlated with decreased ability to repeat spoken language. Comprehension deficits after stroke were associated with lower FA values in the arcuate fasciculus of the left hemisphere. The findings for repetition were independent of MR imaging ratings of the degree of damage to cortical areas of the left hemisphere involved in language function. There were no findings for homotopic tracts in the right hemisphere. CONCLUSION: This study provides support for a specific role for damage to the superior longitudinal and arcuate fasciculi in the left hemisphere in patients with deficits in repetition of speech in aphasia after stroke.

Disruption of limbic pathways in a case of profound amnesia.

We report a case of episodic amnesia in which the anatomical basis of injury was investigated by diffusion tensor imaging (DTI). Two months after an adult male suffered severe closed head injury, conventional magnetic resonance imaging (CMRI) revealed only a right superior frontal lesion. However, 14 years later, DTI revealed structural anomalies not visible on CMRI involving limbic white matter tracts, notably the fornix, which could explain the amnesia.

Functional neuroimaging with MEG: normative language profiles.

The reliability of language-specific brain activation profiles was assessed using Magnetoencephalography (MEG) in five experiments involving ninety-seven normal volunteers of both genders ranging in age from seven to eighty-four years. MEG data were analyzed with a fully automated method to eliminate subjective judgments in the process of deriving the activation profiles. Across all experiments, profiles were characterized by significant bilateral activity centered in the superior temporal gyrus, and in activity lateralized to the left middle temporal gyrus. These features were invariant across age, gender, variation in task characteristics, and mode of stimulus presentation. The absolute amount of activation, however, did decline with age in the auditory tasks. Moreover, contrary to the commonly held belief that left hemisphere dominance for language is greater in men than in women, our data revealed an opposite albeit a not consistently significant trend.

Heliconius wing patterns: an evo-devo model for understanding phenotypic diversity.

Evolutionary Developmental Biology aims for a mechanistic understanding of phenotypic diversity, and present knowledge is largely based on gene expression and interaction patterns from a small number of well-known model organisms. However, our understanding of biological diversification depends on our ability to pinpoint the causes of natural variation at a micro-evolutionary level, and therefore requires the isolation of genetic and developmental variation in a controlled genetic background. The colour patterns of Heliconius butterflies (Nymphalidae: Heliconiinae) provide a rich suite of naturally occurring variants with striking phenotypic diversity and multiple taxonomic levels of variation. Diversification in the genus is well known for its dramatic colour-pattern divergence between races or closely related species, and for Müllerian mimicry convergence between distantly related species, providing a unique system to study the development basis of colour-pattern evolution. A long history of genetic studies has showed that pattern variation is based on allelic combinations at a surprisingly small number of loci, and recent developmental evidence suggests that pattern development in Heliconius is different from the eyespot determination of other butterflies. Fine-scale genetic mapping studies have shown that a shared toolkit of genes is used to produce both convergent and divergent phenotypes. These exciting results and the development of new genomic resources make Heliconius a very promising evo-devo model for the study of adaptive change.

Organization of receptive language-specific cortex before and after left temporal lobectomy.

OBJECTIVE: To examine brain activation associated with receptive language in patients with left temporal lobe epilepsy (TLE) before and after an anterior temporal lobectomy using magnetoencephalography (MEG), and to evaluate which patients were most likely to show a change in the lateralization and localization of the mechanisms supporting receptive language and if such changes were associated with neuropsychological function. METHODS: Twelve patients with left TLE underwent preoperative Wada testing, and pre- and postoperative neuropsychological testing and MEG language mapping. The anatomic location of receptive language-related activity sources observed with MEG was determined by coregistering MEG data with structural MRI scans. Language laterality indices were calculated based on the number of reproducible activity sources in each hemisphere. The proximity of language-specific activity sources to Wernicke's area was also examined. RESULTS: Although the small sample size precluded formal statistical analyses, patients with atypical (bilateral) hemispheric dominance preoperatively were more likely than patients with typical (left-hemisphere) dominance to show evidence of increased right hemisphere participation in language functions after surgery. Patients with left hemispheric dominance preoperatively were more likely to show intrahemispheric changes involving a slight inferior shift of the putative location of Wernicke's area. Patients with bilateral representation tended to perform worse on neuropsychological test measures obtained both pre- and postoperatively. CONCLUSION: Interhemispheric functional reorganization of language-specific areas may occur in patients undergoing left anterior temporal lobectomy. Intrahemispheric reorganization may take place even when the resection does not directly impinge upon Wernicke's area.

Spatio-temporal cortical dynamics of phonemic and semantic fluency.

Hemodynamic brain imaging and lesion studies have suggested differential involvement of expressive language-related cortical regions based on the phonemic versus semantic characteristics of verbal cues. The aims of this study were: 1) to elucidate the relative timing of the activity of inferior frontal and anterior insular versus motor and supplementary motor cortex during a fluency task and 2) to assess potential differences in the location or timing of activity in anterior and posterior language areas based on letter versus category cues. Using magnetic source imaging (MSI), we found significantly earlier onset latencies and a greater number of activity sources in motor and supplementary motor compared with inferior frontal and anterior insular regions. We also observed greater left versus right hemispheric asymmetry of activation for letter compared with category cues. This study provides new insights into cortico-cortical interactions during expressive language tasks.