bluuebunny/crossref_metadata_2025 huggingface dataset:
Fabrication of disconnected three-dimensional silver nanostructures in a polymer matrix
Authors: Vora Kevin , Kang SeungYeon , Shukla Shobha , Mazur Eric
Published: February 2012

We present a simple, one-step technique for direct-writing of a structured nanocomposite material with disconnected silver nanostructures in a polymer matrix. A nonlinear optical interaction between femtosecond laser pulses and a composite material creates silver structures that are embedded inside a polymer with submicrometer resolution (300 nm). We create complex patterns of silver nanostructures in three dimensions. The key to the process is the chemical composition of the sample that provides both a support matrix and controlled growth. The technique presented in this letter may offer a cost-effective approach for the fabrication of bulk optical devices with engineered dispersion.
Transparent conductive thin films of single-wall carbon nanotubes encapsulating dopant molecules
Authors: Kishi Naoki , Miwa Ikuma , Okazaki Toshiya , Saito Takeshi , Mizutani Toshihisa , Tsuchiya Hiroaki , Soga Tetsuo , Jimbo Takashi
Published: February 2012

Transparent conductive thin films of single-wall carbon nanotubes (SWCNTs) doped with organic dopant molecules encapsulated inside the SWCNTs are reported. Doping with tetrafluorotetracyano-p-quinodimethane encapsulated within the SWCNTs improved the ratio of direct current to optical conductivity in the SWCNT thin films by a factor of about 1.8. Thermal stability of the improvement in electrical conductivity by encapsulation doping is investigated as a function of annealing temperature. We found that encapsulation doping provides stable conductivity enhancement in transparent thin films of SWCNTs compared to doping by adsorbed dopant molecules outside the SWCNTs.
Seasonal variation in the ovarian function of sows
Authors: Bertoldo M. J. , Holyoake P. K. , Evans G. , Grupen C. G.
Published: February 2012

The modern domestic sow exhibits a period of impaired reproductive performance known as seasonal infertility during the late summer and early autumn months. A reduction in farrowing rate due to pregnancy loss is the most economically significant manifestation of this phenomenon. Presently, little is known of the aetiology of seasonal pregnancy loss in the pig. Recent findings represent a major advancement in the understanding of sow reproductive physiology and implicate poor oocyte developmental competence as a contributing factor to pregnancy loss during the seasonal infertility period. It has also been demonstrated that ovarian activity is depressed during the seasonal infertility period. The reduction in oocyte quality is associated with decreased levels of progesterone in follicular fluid during final oocyte maturation in vivo. The recent identification of sow-specific risk factors, such as parity for late pregnancy loss, should improve breeding herd efficiency by allowing producers to tailor management interventions and/or culling protocols that target animals identified as having a greater risk of late pregnancy loss during the seasonal infertility period.
Spatial variability in wildfire probability across the western United States
Authors: Parisien Marc-André , Snetsinger Susan , Greenberg Jonathan A. , Nelson Cara R. , Schoennagel Tania , Dobrowski Solomon Z. , Moritz Max A.
Published: February 2012

Despite growing knowledge of fire–environment linkages in the western USA, obtaining reliable estimates of relative wildfire likelihood remains a work in progress. The purpose of this study is to use updated fire observations during a 25-year period and a wide array of environmental variables in a statistical framework to produce high-resolution estimates of wildfire probability. Using the MaxEnt modelling technique, point-source fire observations that were sampled from area burned during the 1984–2008 time period were related to explanatory variables representing ignitions, flammable vegetation (i.e. fuels), climate and topography. Model results were used to produce spatially explicit predictions of wildfire probability. To assess the effect of humans on the spatial patterns of wildfire likelihood, we built an alternative model that excluded all variables having a strong anthropogenic imprint. Results showed that wildfire probability in the western USA is far from uniform, with different areas responding to different environmental drivers. The effect of anthropogenic factors on wildfire probability varied by region but, on the whole, humans appear to inhibit fire activity in the western USA. Our results not only provide what appear to be robust predictions of wildfire likelihood, but also enhance understanding of long-term controls on wildfire activity. In addition, our wildfire probability maps provide better information for strategic planning of land-management activities, especially where fire regime knowledge is sparse.
A Y-linked anti-Müllerian hormone duplication takes over a critical role in sex determination
Authors: Hattori Ricardo S. , Murai Yu , Oura Miho , Masuda Shuji , Majhi Sullip K. , Sakamoto Takashi , Fernandino Juan I. , Somoza Gustavo M. , Yokota Masashi , Strüssmann Carlos A.
Published: February 2012

Gonadal sex determination in vertebrates generally follows a sequence of genetically programmed events. In what is seemingly becoming a pattern, all confirmed or current candidate “master” sex-determining genes reported in this group, e.g.,
SRY
in eutherian mammals,
DMY/dmrt1bY
in medaka,
DM-W
in the African clawed frog, and
DMRT1
in chicken encode transcription factors. In contrast, here we show that a male-specific, duplicated copy of the anti-Müllerian hormone (
amh
) is implicated in testicular development of the teleost fish Patagonian pejerrey (
Odontesthes hatcheri
)
.
The gene, termed
amhy
because it is found in a single metacentric/submetacentric chromosome of XY individuals, is expressed much earlier than the autosomal
amh
(6 d after fertilization vs. 12 wk after fertilization) and is localized to presumptive Sertoli cells of XY males during testicular differentiation. Moreover,
amhy
knockdown in XY embryos resulted in the up-regulation of
foxl2
and
cyp19a1a
mRNAs and the development of ovaries. These results are evidence of a functional
amh
duplication in vertebrates and suggest that
amhy
may be the master sex-determining gene in this species. If confirmed, this would be a unique instance of a hormone-related gene, a member of the TGF-β superfamily, in such a role.
Tropoelastin bridge region positions the cell-interactive C terminus and contributes to elastic fiber assembly
Authors: Yeo Giselle C. , Baldock Clair , Tuukkanen Anne , Roessle Manfred , Dyksterhuis Leanne B. , Wise Steven G. , Matthews Jacqueline , Mithieux Suzanne M. , Weiss Anthony S.
Published: February 2012

The tropoelastin monomer undergoes stages of association by coacervation, deposition onto microfibrils, and cross-linking to form elastic fibers. Tropoelastin consists of an elastic N-terminal coil region and a cell-interactive C-terminal foot region linked together by a highly exposed bridge region. The bridge region is conveniently positioned to modulate elastic fiber assembly through association by coacervation and its proximity to dominant cross-linking domains. Tropoelastin constructs that either modify or remove the entire bridge and downstream regions were assessed for elastogenesis. These constructs focused on a single alanine substitution (R515A) and a truncation (M155n) at the highly conserved arginine 515 site that borders the bridge. Each form displayed less efficient coacervation, impaired hydrogel formation, and decreased dermal fibroblast attachment compared to wild-type tropoelastin. The R515A mutant protein additionally showed reduced elastic fiber formation upon addition to human retinal pigmented epithelium cells and dermal fibroblasts. The small-angle X-ray scattering nanostructure of the R515A mutant protein revealed greater conformational flexibility around the bridge and C-terminal regions. This increased flexibility of the R515A mutant suggests that the tropoelastin R515 residue stabilizes the structure of the bridge region, which is critical for elastic fiber assembly.
A serpentinite-hosted ecosystem in the Southern Mariana Forearc
Authors: Ohara Yasuhiko , Reagan Mark K. , Fujikura Katsunori , Watanabe Hiromi , Michibayashi Katsuyoshi , Ishii Teruaki , Stern Robert J. , Pujana Ignacio , Martinez Fernando , Girard Guillaume , Ribeiro Julia , Brounce Maryjo , Komori Naoaki , Kino Masashi
Published: February 2012

Several varieties of seafloor hydrothermal vents with widely varying fluid compositions and temperatures and vent communities occur in different tectonic settings. The discovery of the Lost City hydrothermal field in the Mid-Atlantic Ridge has stimulated interest in the role of serpentinization of peridotite in generating H
2
- and CH
4
-rich fluids and associated carbonate chimneys, as well as in the biological communities supported in highly reduced, alkaline environments. Abundant vesicomyid clam communities associated with a serpentinite-hosted hydrothermal vent system in the southern Mariana forearc were discovered during a DSV
Shinkai 6500
dive in September 2010. We named this system the “Shinkai Seep Field (SSF).” The SSF appears to be a serpentinite-hosted ecosystem within a forearc (convergent margin) setting that is supported by fault-controlled fluid pathways connected to the decollement of the subducting slab. The discovery of the SSF supports the prediction that serpentinite-hosted vents may be widespread on the ocean floor. The discovery further indicates that these serpentinite-hosted low-temperature fluid vents can sustain high-biomass communities and has implications for the chemical budget of the oceans and the distribution of abyssal chemosynthetic life.
Experimental viral evolution to specific host
MHC
genotypes reveals fitness and virulence trade-offs in alternative
MHC
types
Authors: Kubinak Jason L. , Ruff James S. , Hyzer Cornelius Whitney , Slev Patricia R. , Potts Wayne K.
Published: February 2012

The unprecedented genetic diversity found at vertebrate
MHC
(major histocompatibility complex) loci influences susceptibility to most infectious and autoimmune diseases. The evolutionary explanation for how these polymorphisms are maintained has been controversial. One leading explanation, antagonistic coevolution (also known as the Red Queen), postulates a never-ending molecular arms race where pathogens evolve to evade immune recognition by common
MHC
alleles, which in turn provides a selective advantage to hosts carrying rare
MHC
alleles. This cyclical process leads to negative frequency-dependent selection and promotes
MHC
diversity if two conditions are met: (
i
) pathogen adaptation must produce trade-offs that result in pathogen fitness being higher in familiar (i.e., host
MHC
genotype adapted to) vs. unfamiliar host
MHC
genotypes; and (
ii
) this adaptation must produce correlated patterns of virulence (i.e., disease severity). Here we test these fundamental assumptions using an experimental evolutionary approach (serial passage). We demonstrate rapid adaptation and virulence evolution of a mouse-specific retrovirus to its mammalian host across multiple
MHC
genotypes. Critically, this adaptive response results in trade-offs (i.e., antagonistic pleiotropy) between host
MHC
genotypes; both viral fitness and virulence is substantially higher in familiar versus unfamiliar
MHC
genotypes. These data are unique in experimentally confirming the requisite conditions of the antagonistic coevolution model of
MHC
evolution and providing quantification of fitness effects for pathogen and host. These data help explain the unprecedented diversity of
MHC
genes, including how disease-causing alleles are maintained.
SWI2/SNF2 chromatin remodeling ATPases overcome polycomb repression and control floral organ identity with the LEAFY and SEPALLATA3 transcription factors
Authors: Wu Miin-Feng , Sang Yi , Bezhani Staver , Yamaguchi Nobutoshi , Han Soon-Ki , Li Zhenteng , Su Yanhui , Slewinski Thomas L. , Wagner Doris
Published: February 2012

Patterning of the floral organs is exquisitely controlled and executed by four classes of homeotic regulators. Among these, the class B and class C floral homeotic regulators are of central importance as they specify the male and female reproductive organs. Inappropriate induction of the class B gene
APETALA3
(
AP3
) and the class C gene
AGAMOUS
(
AG
) causes reduced reproductive fitness and is prevented by polycomb repression. At the onset of flower patterning, polycomb repression needs to be overcome to allow induction of
AP3
and
AG
and formation of the reproductive organs. We show that the SWI2/SNF2 chromatin-remodeling ATPases SPLAYED (SYD) and BRAHMA (BRM) are redundantly required for flower patterning and for the activation of
AP3
and
AG
. The SWI2/SNF2 ATPases are recruited to the regulatory regions of
AP3
and
AG
during flower development and physically interact with two direct transcriptional activators of class B and class C gene expression, LEAFY (LFY) and SEPALLATA3 (SEP3). SYD and LFY association with the
AP3
and
AG
regulatory loci peaks at the same time during flower patterning, and SYD binding to these loci is compromised in
lfy
and
lfy sep3
mutants. This suggests a mechanism for SWI2/SNF2 ATPase recruitment to these loci at the right stage and in the correct cells. SYD and BRM act as trithorax proteins, and the requirement for SYD and BRM in flower patterning can be overcome by partial loss of polycomb activity in
curly leaf
(
clf
) mutants, implicating the SWI2/SNF2 chromatin remodelers in reversal of polycomb repression.
Identification of innate immunity elicitors using molecular signatures of natural selection
Authors: McCann Honour C. , Nahal Hardeep , Thakur Shalabh , Guttman David S.
Published: February 2012

The innate immune system is an ancient and broad-spectrum defense system found in all eukaryotes. The detection of microbial elicitors results in the up-regulation of defense-related genes and the elicitation of inflammatory and apoptotic responses. These innate immune responses are the front-line barrier against disease because they collectively suppress the growth of the vast majority of invading microbes. Despite their critical role, we know remarkably little about the diversity of immune elicitors. To address this paucity, we reasoned that hosts are more likely to evolve recognition to “core” pathogen proteins under strong negative selection for the maintenance of essential cellular functions, whereas repeated exposure to host–defense responses will impose strong positive selective pressure for elicitor diversification to avoid host recognition. Therefore, we hypothesized that novel bacterial elicitors can be identified through these opposing forces of natural selection. We tested this hypothesis by examining the genomes of six bacterial phytopathogens and identifying 56 candidate elicitors that have an excess of positively selected residues in a background of strong negative selection. We show that these positively selected residues are atypically clustered, similar to patterns seen in the few well-characterized elicitors. We then validated selected candidate elicitors by showing that they induce
Arabidopsis thaliana
innate immunity in functional (virulence suppression) and cellular (callose deposition) assays. These finding provide targets for the study of host–pathogen interactions and applied research into alternative antimicrobial treatments.
Pancreatic islet expression of chemokine CCL2 suppresses autoimmune diabetes via tolerogenic CD11c+CD11b+dendritic cells
Authors: Kriegel Martin A. , Rathinam Chozhavendan , Flavell Richard A.
Published: February 2012

Development of type 1 diabetes in the nonobese diabetic (NOD) mouse is preceded by an immune cell infiltrate in the pancreatic islets. The exact role of the attracted cells is still poorly understood. Chemokine CCL2/MCP-1 is known to attract CCR2+monocytes and dendritic cells (DCs). We have previously shown that transgenic expression of CCL2 in pancreatic islets via the rat insulin promoter induces nondestructive insulitis on a nonautoimmune background. We report here an unexpected reduction of diabetes development on the NOD background despite an increased islet cell infiltrate with markedly increased numbers of CD11c+CD11b+DCs. These DCs exhibited a hypoactive phenotype with low CD40, MHC II, CD80/CD86 expression, and reduced TNF-α but elevated IL-10 secretions. They failed to induce proliferation of diabetogenic CD4+T cells in vitro. Pancreatic lymph node CD4+T cells were down-regulated ex vivo and expressed the anergy markerGrail. By using an in vivo transfer system, we show that CD11c+CD11b+DCs from rat insulin promoter-CCL2 transgenic NOD mice were the most potent cells suppressing diabetes development. These findings support an unexpected beneficial role for CCL2 in type 1 diabetes with implications for current strategies interfering with the CCL2/CCR2 axis in humans, and for dendritic cell biology in autoimmunity.
Temporally-independent functional modes of spontaneous brain activity
Authors: Smith Stephen M. , Miller Karla L. , Moeller Steen , Xu Junqian , Auerbach Edward J. , Woolrich Mark W. , Beckmann Christian F. , Jenkinson Mark , Andersson Jesper , Glasser Matthew F. , Van Essen David C. , Feinberg David A. , Yacoub Essa S. , Ugurbil Kamil
Published: February 2012

Resting-state functional magnetic resonance imaging has become a powerful tool for the study of functional networks in the brain. Even “at rest,” the brain's different functional networks spontaneously fluctuate in their activity level; each network's spatial extent can therefore be mapped by finding temporal correlations between its different subregions. Current correlation-based approaches measure the average functional connectivity between regions, but this average is less meaningful for regions that are part of multiple networks; one ideally wants a network model that explicitly allows overlap, for example, allowing a region's activity pattern to reflect one network's activity some of the time, and another network's activity at other times. However, even those approaches that do allow overlap have often maximized mutual spatial independence, which may be suboptimal if distinct networks have significant overlap. In this work, we identify functionally distinct networks by virtue of their temporal independence, taking advantage of the additional temporal richness available via improvements in functional magnetic resonance imaging sampling rate. We identify multiple “temporal functional modes,” including several that subdivide the default-mode network (and the regions anticorrelated with it) into several functionally distinct, spatially overlapping, networks, each with its own pattern of correlations and anticorrelations. These functionally distinct modes of spontaneous brain activity are, in general, quite different from resting-state networks previously reported, and may have greater biological interpretability.
Phosphorylation of dedicator of cytokinesis 1 (Dock180) at tyrosine residue Y722 by Src family kinases mediates EGFRvIII-driven glioblastoma tumorigenesis
Authors: Feng Haizhong , Hu Bo , Jarzynka Michael J. , Li Yanxin , Keezer Susan , Johns Terrance G. , Tang Careen K. , Hamilton Ronald L. , Vuori Kristiina , Nishikawa Ryo , Sarkaria Jann N. , Fenton Tim , Cheng Tao , Furnari Frank B. , Cavenee Webster K. , Cheng Shi-Yuan
Published: February 2012

Glioblastoma, the most common primary malignant cancer of the brain, is characterized by rapid tumor growth and infiltration of tumor cells throughout the brain. These traits cause glioblastomas to be highly resistant to current therapies with a resultant poor prognosis. Although aberrant oncogenic signaling driven by signature genetic alterations, such as EGF receptor (EGFR) gene amplification and mutation, plays a major role in glioblastoma pathogenesis, the responsible downstream mechanisms remain less clear. Here, we report that EGFRvIII (also known as ΔEGFR and de2-7EGFR), a constitutively active EGFR mutant that is frequently co-overexpressed with EGFR in human glioblastoma, promotes tumorigenesis through Src family kinase (SFK)-dependent phosphorylation of Dock180, a guanine nucleotide exchange factor for Rac1. EGFRvIII induces phosphorylation of Dock180 at tyrosine residue 722 (Dock180
Y722
) and stimulates Rac1-signaling, glioblastoma cell survival and migration. Consistent with this being causal, siRNA knockdown of Dock180 or expression of a Dock180
Y722F
mutant inhibits each of these EGFRvIII-stimulated activities. The SFKs, Src, Fyn, and Lyn, induce phosphorylation of Dock180
Y722
and inhibition of these SFKs by pharmacological inhibitors or shRNA depletion markedly attenuates EGFRvIII-induced phosphorylation of Dock180
Y722
, Rac1 activity, and glioblastoma cell migration. Finally, phosphorylated Dock180
Y722
is coexpressed with EGFRvIII and phosphorylated Src
Y418
in clinical specimens, and such coexpression correlates with an extremely poor survival in glioblastoma patients. These results suggest that targeting the SFK-p-Dock180
Y722
-Rac1 signaling pathway may offer a novel therapeutic strategy for glioblastomas with EGFRvIII overexpression.
Novel Praziquantel Treatment Regime for Controlling Asian Tapeworm Infections in Pond-Reared Fish
Authors: Iles Alison C , Archdeacon Thomas P , Bonar Scott A
Published: February 2012

The Asian tapeworm Bothriocephalus achelognathii is an intestinal fish parasite that is nonnative to but widespread throughout the southwestern United States. Praziquantel is an anthelminthic drug commonly used to treat fish for Asian tapeworm; however, it does not kill tapeworm eggs, so the water in ponds used for fish rearing must be exchanged after treatment. Our objective was to determine whether a system containing both an intermediate copepod host and a definitive fish host for Asian tapeworm could be treated without exchanging the water by using a follow-up treatment for any tapeworms that developed from eggs released before or during the first treatment. Here, we have described a new praziquantel treatment regimen to control Asian tapeworm infections in freshwater-reared fish. To evaluate the efficacy of this regimen, we stocked 50 red shiners Cyprinella lutrensis and an intermediate copepod host, Cyclops vernalis, into each of six pond mesocosms containing artificial macrophytes, sand, and gravel to simulate natural pools and provide suitable substrate for the copepod's life history. The test fish population had been naturally infected with B. achelognathii and had an initial infection prevalence of 14% and an infection intensity of 2.14 ± 2.19 (mean ± SD) worms per fish. Three mesocosms were treated twice, each with 2.5 mg/L praziquantel; 19 d passed between treatments to allow for possible reinfection to occur. After a 2.5-month posttreatment period to allow any remaining tapeworms to reestablish themselves, we killed and dissected all of the remaining fish. No worms were found in treated fish; however, the control group had an infection prevalence of 18 ± 6% and an infection intensity of 3.45 ± 2.1 worms per fish. Based on these results, we concluded that the praziquantel treatment regime administered was efficacious and suggest testing it on a larger scale. We caution that praziquantel has not been approved by the U.S. Food and Drug Administration for use on fish but can be used legally in some situations.
WaVPeak: picking NMR peaks through wavelet-based smoothing and volume-based filtering
Authors: Liu Zhi , Abbas Ahmed , Jing Bing-Yi , Gao Xin
Published: February 2012

Motivation: Nuclear magnetic resonance (NMR) has been widely used as a powerful tool to determine the 3D structures of proteins in vivo. However, the post-spectra processing stage of NMR structure determination usually involves a tremendous amount of time and expert knowledge, which includes peak picking, chemical shift assignment and structure calculation steps. Detecting accurate peaks from the NMR spectra is a prerequisite for all following steps, and thus remains a key problem in automatic NMR structure determination.

Results: We introduce WaVPeak, a fully automatic peak detection method. WaVPeak first smoothes the given NMR spectrum by wavelets. The peaks are then identified as the local maxima. The false positive peaks are filtered out efficiently by considering the volume of the peaks.

WaVPeak has two major advantages over the state-of-the-art peak-picking methods. First, through wavelet-based smoothing, WaVPeak does not eliminate any data point in the spectra. Therefore, WaVPeak is able to detect weak peaks that are embedded in the noise level. NMR spectroscopists need the most help isolating these weak peaks. Second, WaVPeak estimates the volume of the peaks to filter the false positives. This is more reliable than intensity-based filters that are widely used in existing methods.

We evaluate the performance of WaVPeak on the benchmark set proposed by PICKY (Alipanahi et al., 2009), one of the most accurate methods in the literature. The dataset comprises 32 2D and 3D spectra from eight different proteins. Experimental results demonstrate that WaVPeak achieves an average of 96%, 91%, 88%, 76% and 85% recall on 15N-HSQC, HNCO, HNCA, HNCACB and CBCA(CO)NH, respectively. When the same number of peaks are considered, WaVPeak significantly outperforms PICKY.

Availability: WaVPeak is an open source program. The source code and two test spectra of WaVPeak are available at http://faculty.kaust.edu.sa/sites/xingao/Pages/Publications.aspx. The online server is under construction.

Contact:  statliuzhi@xmu.edu.cn; ahmed.abbas@kaust.edu.sa; majing@ust.hk; xin.gao@kaust.edu.sa
Prevalence and prognosis of heart failure with preserved ejection fraction and elevated N‐terminal pro brain natriuretic peptide: a 10‐year analysis from the Copenhagen Hospital Heart Failure Study
Authors: Carlsen Christian Malchau , Bay Morten , Kirk Vibeke , Gøtze Jens Peter , Køber Lars , Nielsen Olav Wendelboe
Published: February 2012

Aims

The aim of this study was to assess the epidemiological features and prognosis of heart failure with preserved ejection fraction (HFPEF) and to compare these findings with those from patients with reduced ejection fraction. Furthermore the effects of N‐terminal pro brain natriuretic peptide (NT‐proBNP) requirement in the heart failure diagnosis were assessed by repeating the analyses in the subgroup of patients with elevated NT‐proBNP.

Methods and results

In 1844 patients admitted, a clinical diagnosis of heart failure was made in 433; amongst these 61% had HFPEF. An elevated NT‐proBNP applied to the heart failure diagnosis reduced the number of heart failure patients to 191, and amongst these 29% had preserved ejection fraction. Use of NT‐proBNP reduced clinical differences between heart failure patients with preserved and reduced ejection fraction. When not using NT‐proBNP, patients with reduced ejection fraction had higher mortality [hazard ratio (HR) 1.24, 95% confidence interval (CI) 1.01–1.52; P = 0.04], even after adjustment for other significant predictors of mortality, except NT‐proBNP (HR 1.29, 95% CI 1.04–1.59; P = 0.02). However, no difference in mortality was observed when NT‐proBNP was adjusted for (HR 0.90, 95% CI 0.71–1.15; P = 0.4), or used for the heart failure diagnosis (HR 0.96; 95% CI 0.71–1.29; P = 0.8).

Conclusion

Using a heart failure diagnosis requiring elevated NT‐proBNP reduces the prevalence of HFPEF and results in a survival similar to that of heart failure with reduced ejection fraction. In contrast, when NT‐proBNP is not used for the heart failure diagnosis or adjusted for, HFPEF is associated with a lower mortality in both univariate and multivariate analysis.
Using Process Analysis to Assess the Impact of Medical Education on the Delivery of Pain Services
Authors: Williams Kayode A. , Chambers Chester G. , Dada Maqbool , Hough Douglas , Aron Ravi , Ulatowski John A.
Published: February 2012

Background

The medical, social, and economic effects of the teaching mission on delivery of care at an academic medical center (AMC) are not fully understood. When a free-standing private practice ambulatory clinic with no teaching mission was merged into an AMC, a natural experiment was created. The authors compared process measures across the two settings to observe the differences in system performance introduced by the added steps and resources of the AMC's teaching mission.

Methods

After creating process maps based on activity times realized in both settings, the authors developed discrete-event simulations of the two environments. The two settings were comparable in the levels of key resources, but the AMC process flow included three residents/fellows. Simulation enabled the authors to consider an identical schedule across the two settings.

Results

Under identical schedules, the average accumulated processing time per patient was higher in the AMC. However, the use of residents allowed simultaneous processing of multiple patients. Consequently, the AMC had higher throughput (3.5 vs. 2.7 patients per hour), higher room utilization (82.2% vs. 75.5%), reduced utilization of the attending physician (79.0% vs. 93.4%), and a shorter average waiting time (30.0 vs. 83.9 min). In addition, the average completion time for the final patient scheduled was 97.9 min less, and the average number of patients treated before incurring overtime was 37.9% greater.

Conclusions

Although the teaching mission of the AMC adds processing steps and costs, the use of trainees within the process serves to increase throughput while decreasing waiting times and the use of overtime.
Gastrointestinal and Nutritional Problems Occur Frequently Throughout Life in Girls and Women With Rett Syndrome
Authors: Motil Kathleen J. , Caeg Erwin , Barrish Judy O. , Geerts Suzanne , Lane Jane B. , Percy Alan K. , Annese Fran , McNair Lauren , Skinner Steven A. , Lee Hye‐Seung , Neul Jeffrey L. , Glaze Daniel G.
Published: February 2012

Objective:

We conducted a nationwide survey to determine the prevalence of common gastrointestinal and nutritional disorders in Rett syndrome (RTT) based on parental reporting and related the occurrence of these problems to age and methyl‐CpG‐binding protein 2 (MECP2) gene status.

Methods:

We designed a questionnaire that probed symptoms, diagnoses, diagnostic tests, and treatment interventions related to gastrointestinal and nutritional problems in RTT. The International Rett Syndrome Foundation distributed the questionnaire to 1666 family‐based members and forwarded their responses for our review. We interrogated the Rare Disease Clinical Research Network database to supplement findings related to medications used to treat gastrointestinal problems in RTT.

Results:

Parents of 983 female patients with RTT (59%) responded and identified symptoms and diagnoses associated with gastrointestinal dysmotility (92%), chewing and swallowing difficulties (81%), weight deficits or excess (47%), growth deficits (45%), low bone mineral content or fractures (37%), and biliary tract disorders (3%). Height‐for‐age, weight‐for‐age, and body mass index z scores decreased significantly with age; height‐ and weight‐, but not body mass index‐for‐age z scores were significantly lower in female subjects with MECP2 mutations than in those without. Vomiting, nighttime awakening, gastroesophageal reflux, chewing difficulty, and choking with feeding were significantly less likely to occur with increasing age. Short stature, low bone mineral content, fractures, and gastrostomy placement were significantly more likely to occur with increasing age. Chewing difficulty, choking with feeding, and nighttime awakening were significantly less likely to occur, whereas short stature was significantly more likely to occur, in female subjects with MECP2 mutations than in those without. Diagnostic evaluations and therapeutic interventions were used less frequently than the occurrence of symptoms or diagnoses in the RTT cohort.

Conclusions:

Gastrointestinal and nutritional problems perceived by parents are prevalent throughout life in girls and women with RTT and may pose a substantial medical burden for their caregivers. Physician awareness of these features of RTT may improve the health and quality of life of individuals affected with this disorder.
Risk of Infection and Prevention in Pediatric Patients With IBD
Authors: Veereman‐Wauters Gigi , de Ridder Lissy , Veres Gábor , Kolacek Sanja , Fell John , Malmborg Petter , Koletzko Sibylle , Dias Jorge Amil , Misak Zrinjka , Rahier Jean‐François , Escher Johanna C. ,   ESPGHAN IBD Porto Group
Published: February 2012

Combined immunosuppression by immunomodulators and biological therapy has become standard in the medical management of moderate‐to‐severe inflammatory bowel disease (IBD) because of clearly demonstrated efficacy. Clinical studies, registries, and case reports warn of the increased risk of infections, particularly opportunistic infections; however, already in the steroid monotherapy era, patients are at risk because it is accepted that a patient should be considered immunosuppressed when receiving a daily dose of 20 mg of prednisone for 2 weeks. Prescriptions increasingly involve azathioprine, methotrexate, and various biological agents. The TREAT registry evaluated safety in >6000 adult patients, half of them treated with infliximab (IFX) for about 1.9 years. IFX‐treated patients had an increased risk of infections and this was associated with disease severity and concomitant prednisone use. The REACH study, evaluating the efficacy of IFX in children with moderate‐to‐severe Crohn disease, refractory to immunomodulatory treatment, reports serious infections as the major adverse events and their frequency is higher with shorter treatment intervals. The combination of immunosuppressive medications is a risk factor for opportunistic infections. Exhaustive guidelines on prophylaxis, diagnosis, and management of opportunistic infections in adult patients with IBD have been published by a European Crohn's and Colitis Organization working group, including clear evidence‐based statements. We have reviewed the literature on infections in pediatric IBD as well as the European Crohn's and Colitis Organization guidelines to present a commentary on infection prophylaxis for the pediatric age group.
One‐step Percutaneous Gastrojejunostomy in Early Infancy
Authors: Michaud Laurent , Robert‐Dehault Amélie , Coopman Stéphanie , Guimber Dominique , Turck Dominique , Gottrand Frédéric
Published: February 2012

In certain conditions that obviate the use of gastric feedings, the insertion of a jejunal feeding tube via gastrostomy constitutes an alternative to jejunostomy but requires a preexisting gastrostomy. Our aim was to assess a new technique of 1‐step gastrojejunal tube insertion through a de novo gastrostomy. A total of 3 infants between 3 and 7 months old and weighing between 4.1 and 5.4 kg had a gastrojejunal feeding tube inserted using a 16‐CH French introducer percutaneous endoscopic gastrostomy kit and a transgastric‐jejunal feeding tube. No technical difficulties occurred and the gastrojejunal feeding tube was placed successfully in the 3 patients, the total procedure lasting 15 to 20 minutes. Enteral feeding was started within 4 to 6 hours of the procedure. Neither immediate (<24 hours) nor late complications related to the gastrojejunostomy occurred. Nissen fundoplication was performed in 2 of our patients at 12 and 15 months of age, respectively. The gastrojejunostomy tube was still in place in the third patient at age 15 months. Our first experience suggests that 1‐step endoscopic placement of a transgastric‐jejunal feeding tube without a preexisting gastrostomy tract is feasible in young and low‐weight infants.
Plant radiation history affects community assembly: evidence from the New Zealand alpine
Authors: Lee William G. , Tanentzap Andrew J. , Heenan Peter B.
Published: February 2012

The hypothesis that early plant radiations on islands dampen diversification and reduce habitat occupancy of later radiations via niche pre-emption has never, to our knowledge, been tested. We investigated clade-level dynamics in plant radiations in the alpine zone, New Zealand. Our aim was to determine whether radiations from older colonizations influenced diversification and community dominance of species from later colonizations within a common bioclimatic zone over the past
ca
10 Myr. We used stem ages derived from the phylogenies of 17 genera represented in alpine plant communities in the Murchison Mountains, Fiordland, and assessed their presence and cover in 262 (5 × 5 m) vegetation plots. Our results show clear age-related community assembly effects, whereby congenerics from older colonizing genera co-occur more frequently and with greater cover per unit area than those from younger colonizing genera. However, we find no evidence of increased species richness with age of colonization in the alpine zone. The data support priority effects via niche pre-emption among plant radiations influencing community assembly.
Two decades of studying non-covalent biomolecular assemblies by means of electrospray ionization mass spectrometry
Authors: Hilton Gillian R. , Benesch Justin L. P.
Published: February 2012

Mass spectrometry (MS) is a recognized approach for characterizing proteins and the complexes they assemble into. This application of a long-established physico-chemical tool to the frontiers of structural biology has stemmed from experiments performed in the early 1990s. While initial studies focused on the elucidation of stoichiometry by means of simple mass determination, developments in MS technology and methodology now allow researchers to address questions of shape, inter-subunit connectivity and protein dynamics. Here, we chart the remarkable rise of MS and its application to biomolecular complexes over the last two decades.
The well-tuned blues: the role of structural colours as optical signals in the species recognition of a local butterfly fauna (Lepidoptera: Lycaenidae: Polyommatinae)
Authors: Bálint Zsolt , Kertész Krisztián , Piszter Gábor , Vértesy Zofia , Biró László P.
Published: February 2012

The photonic nanoarchitectures responsible for the blue colour of the males of nine polyommatine butterfly species living in the same site were investigated structurally by electron microscopy and spectrally by reflectance spectroscopy. Optical characterization was carried out on 110 exemplars. The structural data extracted by dedicated software and the spectral data extracted by standard software were inputted into an artificial neural network software to test the specificity of the structural and optical characteristics. It was found that both the structural and the spectral data allow species identification with an accuracy better than 90 per cent. The reflectance data were further analysed using a colour representation diagram built in a manner analogous to that of the human Commission Internationale de l'Eclairage diagram, but the additional blue visual pigment of lycaenid butterflies was taken into account. It was found that this butterfly-specific colour representation diagram yielded a much clearer distinction of the position of the investigated species compared with previous calculations using the human colour space. The specific colours of the investigated species were correlated with the 285 flight-period data points extracted from museum collections. The species with somewhat similar colours fly in distinct periods of the year such that the blue colours are well tuned for safe mate/competitor recognition. This allows for the creation of an effective pre-zygotic isolation mechanism for closely related synchronic and syntopic species.
Evidence that ship noise increases stress in right whales
Authors: Rolland Rosalind M. , Parks Susan E. , Hunt Kathleen E. , Castellote Manuel , Corkeron Peter J. , Nowacek Douglas P. , Wasser Samuel K. , Kraus Scott D.
Published: February 2012

Baleen whales (Mysticeti) communicate using low-frequency acoustic signals. These long-wavelength sounds can be detected over hundreds of kilometres, potentially allowing contact over large distances. Low-frequency noise from large ships (20–200 Hz) overlaps acoustic signals used by baleen whales, and increased levels of underwater noise have been documented in areas with high shipping traffic. Reported responses of whales to increased noise include: habitat displacement, behavioural changes and alterations in the intensity, frequency and intervals of calls. However, it has been unclear whether exposure to noise results in physiological responses that may lead to significant consequences for individuals or populations. Here, we show that reduced ship traffic in the Bay of Fundy, Canada, following the events of 11 September 2001, resulted in a 6 dB decrease in underwater noise with a significant reduction below 150 Hz. This noise reduction was associated with decreased baseline levels of stress-related faecal hormone metabolites (glucocorticoids) in North Atlantic right whales (Eubalaena glacialis). This is the first evidence that exposure to low-frequency ship noise may be associated with chronic stress in whales, and has implications for all baleen whales in heavy ship traffic areas, and for recovery of this endangered right whale population.
Multilocus genetic analyses differentiate between widespread and spatially restricted cryptic species in a model ascidian
Authors: Bock Dan G. , MacIsaac Hugh J. , Cristescu Melania E.
Published: February 2012

Elucidating the factors that shape species distributions has long been a fundamental goal in ecology and evolutionary biology. In spite of significant theoretical advancements, empirical studies of range limits have lagged behind. Specifically, little is known about how the attributes that allow species to expand their ranges and become widespread vary across phylogenies. Here, we studied the ascidianBotryllus schlosseri, a worldwide invasive species that is also characterized by marked genetic subdivision. Our study includes phylogenetic and population genetic data based on mitochondrial and nuclear genes, as well as polymorphic microsatellites forB. schlossericolonies sampled from the southern and northern coasts of Europe and the eastern and western coasts of North America. We demonstrate that this well-known model organism comprises three highly divergent and probably reproductively isolated cryptic species (A, D and E), with two more (B and C) being suggested by data retrieved from GenBank. Among these, species A, recovered in all of the surveyed regions, is by far the most common and widespread. By contrast, species B–E, occurring mostly in sites from northern Europe, are considerably more geographically restricted. These findings, along with inferences made on transport opportunity, suggest that divergent evolutionary histories promoted differences in invasive potential betweenB. schlosserisibling species, indicating that attributes that facilitate dramatic shifts in range limits can evolve more easily and frequently than previously thought. We propose environmental disturbance as a selective force that could have shaped the evolution of invasiveness in theB. schlossericomplex.
To feed or to breed: morphological constraints of mouthbrooding in coral reef cardinalfishes
Authors: Hoey Andrew S. , Bellwood David R. , Barnett Adam
Published: February 2012

Functionally coupled biomechanical systems are widespread in nature and are viewed as major constraints on evolutionary diversification, yet there have been few attempts to explore the implications of performing multiple functions within a single anatomical structure. Paternally mouthbrooding cardinalfishes present an ideal system to investigate the constraints of functional coupling as the oral jaws of male fishes are directly responsible for both feeding and reproductive functions. To test the effects of (i) mouthbrooding on feeding and (ii) feeding on reproductive potential we compared the feeding apparatus between sexes of nine species of cardinalfish and compared brood characteristics among species from different trophic groups, respectively. Mouthbrooding was strongly associated with the morphology of the feeding apparatus in males. Male cardinalfishes possessed longer heads, snouts and jaws than female conspecifics irrespective of body size, trophic group or evolutionary history. Conversely, reproductive potential also appeared to be related to trophic morphology. Piscivorous cardinalfishes produced larger, but fewer eggs, and had smaller brood volumes than species from the two invertebrate feeding groups. These interrelationships suggest that feeding and reproduction in the mouth of cardinalfishes may be tightly coupled. If so this may, in part, have contributed to the limited morphological diversification exhibited by cardinalfishes.
Why are there so few fish in the sea?
Authors: Carrete Vega Greta , Wiens John J.
Published: February 2012

The most dramatic gradient in global biodiversity is between marine and terrestrial environments. Terrestrial environments contain approximately 75–85% of all estimated species, but occupy only 30 per cent of the Earth's surface (and only approx. 1–10% by volume), whereas marine environments occupy a larger area and volume, but have a smaller fraction of Earth's estimated diversity. Many hypotheses have been proposed to explain this disparity, but there have been few large-scale quantitative tests. Here, we analyse patterns of diversity in actinopterygian (ray-finned) fishes, the most species-rich clade of marine vertebrates, containing 96 per cent of fish species. Despite the much greater area and productivity of marine environments, actinopterygian richness is similar in freshwater and marine habitats (15 150 versus 14 740 species). Net diversification rates (speciation–extinction) are similar in predominantly freshwater and saltwater clades. Both habitats are dominated by two hyperdiverse but relatively recent clades (Ostariophysi and Percomorpha). Remarkably, trait reconstructions (for both living and fossil taxa) suggest that all extant marine actinopterygians were derived from a freshwater ancestor, indicating a role for ancient extinction in explaining low marine richness. Finally, by analysing an entirely aquatic group, we are able to better sort among potential hypotheses for explaining the paradoxically low diversity of marine environments.
Nesterenkonia suensis sp. nov., a haloalkaliphilic actinobacterium isolated from a salt pan
Authors: Govender Lucretia , Naidoo Lureshini , Setati Mathabatha Evodia
Published: February 2012

A Gram-positive, non-motile, non-spore-forming actinobacterium designated strain Sua-BAC020T was isolated from brine from Sua salt pan in Botswana. The strain was alkaliphilic and moderately halophilic, displaying optimal growth at 35–37 °C, pH 9 and 2.5 % (w/v) NaCl. Comparative 16S rRNA gene sequence analysis showed that strain Sua-BAC020T belonged to the genus

Nesterenkonia

, sharing 96.2–99.0 % sequence similarity with the type strains of recognized species within this genus. DNA–DNA hybridization with the type strains of species that showed the closest phylogenetic affiliation,

Nesterenkonia xinjiangensis

(16S rRNA gene sequence similarity, 98.9 %),

Nesterenkonia aethiopica

(99.0 %),

Nesterenkonia halophila

(97.5 %),

Nesterenkonia flava

(97.4 %) and

Nesterenkonia halobia

(97.2 %), gave relatedness values of 10–45 %. The peptidoglycan type of strain Sua-BAC020T was A4α, l-Lys–Gly–d-Asp. Cells of the isolate contained phosphatidylglycerol, diphosphatidylglycerol, phosphatidylinositol and unidentified glycolipids as major polar lipids, MK-8, MK-9 and MK-7 were the predominant menaquinones, and the major fatty acids (>10 %) were anteiso-C15 : 0 and anteiso-C17 : 0. The DNA G+C content of strain Sua-BAC020T was 64.8 mol%. Based on DNA–DNA hybridization, and physiological and biochemical tests, strain Sua-BAC020T is distinct from all recognized

Nesterenkonia

species, suggesting that this strain represents a novel species, for which the name Nesterenkonia suensis sp. nov. is proposed. The type strain is Sua-BAC020T ( = DSM 22748T = NCCB 100309T).