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Atmospheric carbon dioxide records indicate that the land surface has acted as a strong global carbon sink over recent decades, with a substantial fraction of this sink probably located in the tropics, particularly in the Amazon. Nevertheless, it is unclear how the terrestrial carbon sink will evolve as climate and atmospheric composition continue to change. Here we analyse the historical evolution of the biomass dynamics of the Amazon rainforest over three decades using a distributed network of 321 plots. While this analysis confirms that Amazon forests have acted as a long-term net biomass sink, we find a long-term decreasing trend of carbon accumulation. Rates of net increase in above-ground biomass declined by one-third during the past decade compared to the 1990s. This is a consequence of growth rate increases levelling off recently, while biomass mortality persistently increased throughout, leading to a shortening of carbon residence times. Potential drivers for the mortality increase include greater climate variability, and feedbacks of faster growth on mortality, resulting in shortened tree longevity. The observed decline of the Amazon sink diverges markedly from the recent increase in terrestrial carbon uptake at the global scale, and is contrary to expectations based on models.

Background: This investigation compared the effects of an extended period of weight-bearing (running) vs. non-weight-bearing (cycling) exercise on hepcidin production and its implications for iron status., Methods: Ten active males performed two separate exercise training blocks with either running (RTB) or cycling (CTB) as the exercise mode. Each block consisted of five training sessions (Day 1, 2, 4, 5, 6) performed over a seven day period that were matched for exercise intensity. Basal venous blood samples were obtained on Day 1 (D1), and on Recovery Days 3 (R3) and 7 (R7) to assess iron status, while basal and 3 h post-exercise urinary hepcidin levels were measured on D1, D2, D6, as well as R3 and R7 (basal levels only) for each condition., Results: Basal urinary hepcidin levels were significantly elevated (p ≤ 0.05) at D2, R3 and R7 as compared to D1 in RTB. Furthermore, 3 h post-exercise urinary hepcidin levels on D1 were also significantly higher in RTB compared to CTB (p ≤ 0.05). In CTB, urinary hepcidin levels were not statistically different on D1 as compared to R7. Iron parameters were not significantly different at D1 compared to R3 and R7 during both conditions., Conclusions: These results suggest that basal hepcidin levels may increase over the course of an extended training program, especially if a weight-bearing exercise modality is undertaken. However, despite any variations in hepcidin production, serum iron parameters in both RTB and CTB were unaffected, possibly due to the short duration of each training block. In comparing running to cycling, non-weight-bearing activity may require more training sessions, or sessions of extended duration, before any significant changes in basal hepcidin levels appear. Chronic elevations in hepcidin levels may help to explain the high incidence of iron deficiency in athletes.

Hepcidin, an important regulator of iron homeostasis, is suggested to be causally related to anemia of inflammation. The aim of this study was to explore the role of plasma hepcidin in anemia among older persons from the general population. The Leiden 85-Plus Study is a population-based study of 85-year olds in Leiden, the Netherlands. Eighty-five-year old inhabitants of Leiden were enrolled between September 1997 and September 1999. At the age of 86, plasma hepcidin was determined with time of flight mass spectrometry in 490 participants [160 (32.7%) male, 114 (23.3%) with anemia]. Anemia was defined according to criteria of the World Health Organization (hemoglobin level <13 g/dL for men and hemoglobin <12 g/dL for women). The median plasma hepcidin level was 3.0 nM [interquartile range (IQR) 1.8-4.9]. We found strong correlations between plasma hepcidin and body iron status, C-reactive protein and erythropoietin levels. Significantly higher hepcidin levels were found in participants with anemia of inflammation (P<0.01), in participants with anemia of kidney disease (P=0.01), and in participants with unexplained anemia (P=0.01) than in participants without anemia. Participants with iron-deficiency anemia had significantly lower plasma hepcidin levels than participants without anemia (P<0.01). In conclusion, older persons with anemia of inflammation have higher hepcidin levels than their counterparts without anemia. The potential clinical value of hepcidin in future diagnostic algorithms for anemia has to be explored.

We examined racial/ethnic disparities in maternal morbidities (MM) and the number of MM during labor and delivery among hospital discharges in Wisconsin. We conducted a retrospective cohort study of hospital discharge data for 206,428 pregnant women aged 13-53 years using 2005-2007 Healthcare Cost and Utilization Project State Inpatient Dataset (HCUP-SID) for Wisconsin. After adjustments for covariates, MM (preterm labor, antepartum and postpartum hemorrhage, hypertension in pregnancy, gestational diabetes, membrane-related disorders, infections and 3rd and 4th perineal lacerations) were examined using logistic regression models, and number of MM (0, 1, 2, >2 MM) were examined using multivariable ordered logistic regressions with partial proportional odds models. African-Americans had significantly higher likelihood of infections (OR = 1.74; 95% CI 1.60-1.89), preterm labor (OR = 1.42; 1.33-1.50), antepartum hemorrhage (OR = 1.63; 1.44-1.83), and hypertension complicating pregnancy (OR = 1.39; 1.31-1.48) compared to Whites. Hispanics, Asian/Pacific Islanders, and Native Americans had significantly higher likelihood of infections, postpartum hemorrhage, and gestational diabetes than Whites. Major perineal lacerations were significantly higher among Asian/Pacific Islanders (OR = 1.53; 1.34-1.75). All minority racial/ethnic groups, except Asians, had significantly higher likelihood of having 0 versus 1, 2 or >2 MM, 0 or 1 versus 2 or >2 MM, and 0, 1 or 2 versus >2 MM than white women. Findings show significant racial/ethnic disparities in MM, and suggest the need for better screening, management, and timely referral of these conditions, particularly among racial/ethnic women. Disparities in MM may be contributing to the high infant mortality and adverse birth outcomes among different racial/ethnic groups in Wisconsin.

Background: Gas chromatography-mass spectrometry (GC-MS) is a technique frequently used in targeted and non-targeted measurements of metabolites. Most existing software tools for processing of raw instrument GC-MS data tightly integrate data processing methods with graphical user interface facilitating interactive data processing. While interactive processing remains critically important in GC-MS applications, high-throughput studies increasingly dictate the need for command line tools, suitable for scripting of high-throughput, customized processing pipelines., Results: PyMS comprises a library of functions for processing of instrument GC-MS data developed in Python. PyMS currently provides a complete set of GC-MS processing functions, including reading of standard data formats (ANDI- MS/NetCDF and JCAMP-DX), noise smoothing, baseline correction, peak detection, peak deconvolution, peak integration, and peak alignment by dynamic programming. A novel common ion single quantitation algorithm allows automated, accurate quantitation of GC-MS electron impact (EI) fragmentation spectra when a large number of experiments are being analyzed. PyMS implements parallel processing for by-row and by-column data processing tasks based on Message Passing Interface (MPI), allowing processing to scale on multiple CPUs in distributed computing environments. A set of specifically designed experiments was performed in-house and used to comparatively evaluate the performance of PyMS and three widely used software packages for GC-MS data processing (AMDIS, AnalyzerPro, and XCMS)., Conclusions: PyMS is a novel software package for the processing of raw GC-MS data, particularly suitable for scripting of customized processing pipelines and for data processing in batch mode. PyMS provides limited graphical capabilities and can be used both for routine data processing and interactive/exploratory data analysis. In real-life GC-MS data processing scenarios PyMS performs as well or better than leading software packages. We demonstrate data processing scenarios simple to implement in PyMS, yet difficult to achieve with many conventional GC-MS data processing software. Automated sample processing and quantitation with PyMS can provide substantial time savings compared to more traditional interactive software systems that tightly integrate data processing with the graphical user interface.

The effect of carbohydrate (CHO) consumption during prolonged endurance running on post-exercise inflammation and hepcidin levels was investigated. Eleven well-trained male endurance athletes completed a graded exercise test, followed by two experimental running trials in a randomized order. The two experimental trials consisted of a 90 min run at 75% of the peak oxygen uptake velocity (vVO(2peak)), while consuming a solution with either 6% CHO or a placebo (PLA) equivalent at 3 ml kg(-1) every 20 min. Serum interleukin-6 (IL-6), free hemoglobin (Hb), haptoglobin (Hp), hepcidin and iron parameters were assessed throughout the post-run recovery period. Serum iron and IL-6 were significantly elevated immediately post-run in both CHO and PLA (p ≤ 0.05), with no differences between trials. Serum-free Hb increased and Hp decreased significantly immediately post-run in both conditions (p ≤ 0.05). Serum soluble transferrin receptor levels were significantly below the baseline at 3 and 24 h post-run in both conditions (p ≤ 0.05). Serum hepcidin concentration recorded 3 h post-run in both conditions was significantly elevated (p ≤ 0.05), and had returned to the baseline by 24 h post-run (p ≤ 0.05). The use of a 6% CHO solution at 3 ml kg(-1) 20 min(-1) during endurance running did not attenuate the inflammatory response and subsequent increase in serum hepcidin levels during the post-run recovery period.

Scholarly publishing and citation practices have developed largely in the absence of versioned documents. The digital age requires new practices to combine the old and the new. We describe how the original published source and a versioned wiki page based on it can be reconciled and combined into a single citation reference. We illustrate the citation mechanism by way of practical examples focusing on journal and wiki publishing of taxon treatments. Specifically, we discuss mechanisms for permanent cross-linking between the static original publication and the dynamic, versioned wiki, as well as for automated export of journal content to the wiki, to reduce the workload on authors, for combining the journal and the wiki citation and for integrating it with the attribution of wiki contributors.

The concept of semantic tagging and its potential for semantic enhancements to taxonomic papers is outlined and illustrated by four exemplar papers published in the present issue of ZooKeys. The four papers were created in different ways: (i) written in Microsoft Word and submitted as non-tagged manuscript (doi: 10.3897/zookeys.50.504); (ii) generated from Scratchpads and submitted as XML-tagged manuscripts (doi: 10.3897/zookeys.50.505 and doi: 10.3897/zookeys.50.506); (iii) generated from an author's database (doi: 10.3897/zookeys.50.485) and submitted as XML-tagged manuscript. XML tagging and semantic enhancements were implemented during the editorial process of ZooKeys using the Pensoft Mark Up Tool (PMT), specially designed for this purpose. The XML schema used was TaxPub, an extension to the Document Type Definitions (DTD) of the US National Library of Medicine Journal Archiving and Interchange Tag Suite (NLM). The following innovative methods of tagging, layout, publishing and disseminating the content were tested and implemented within the ZooKeys editorial workflow: (1) highly automated, fine-grained XML tagging based on TaxPub; (2) final XML output of the paper validated against the NLM DTD for archiving in PubMedCentral; (3) bibliographic metadata embedded in the PDF through XMP (Extensible Metadata Platform); (4) PDF uploaded after publication to the Biodiversity Heritage Library (BHL); (5) taxon treatments supplied through XML to Plazi; (6) semantically enhanced HTML version of the paper encompassing numerous internal and external links and linkouts, such as: (i) vizualisation of main tag elements within the text (e.g., taxon names, taxon treatments, localities, etc.); (ii) internal cross-linking between paper sections, citations, references, tables, and figures; (iii) mapping of localities listed in the whole paper or within separate taxon treatments; (v) taxon names autotagged, dynamically mapped and linked through the Pensoft Taxon Profile (PTP) to large international database services and indexers such as Global Biodiversity Information Facility (GBIF), National Center for Biotechnology Information (NCBI), Barcode of Life (BOLD), Encyclopedia of Life (EOL), ZooBank, Wikipedia, Wikispecies, Wikimedia, and others; (vi) GenBank accession numbers autotagged and linked to NCBI; (vii) external links of taxon names to references in PubMed, Google Scholar, Biodiversity Heritage Library and other sources. With the launching of the working example, ZooKeys becomes the first taxonomic journal to provide a complete XML-based editorial, publication and dissemination workflow implemented as a routine and cost-efficient practice. It is anticipated that XML-based workflow will also soon be implemented in botany through PhytoKeys, a forthcoming partner journal of ZooKeys. The semantic markup and enhancements are expected to greatly extend and accelerate the way taxonomic information is published, disseminated and used.

A 36-year old female patient who had had iron deficiency anaemia since her childhood showed no clear response to oral iron treatment. Elevated serum hepcidin levels were found after excluding other causes of iron deficiency. This is in contrast to what is expected in iron deficiency anaemia and indicates a primary defect in hepcidin regulation. Indeed, in the search for a defect in genes coding for hepcidin-regulating proteins the patient was found to be compound heterozygous for two different mutations in the TMPRSS6 gene. This leads to a dysfunctional matriptase-2 protein for which the gene codes. Consequently, liver cells cannot inhibit hepcidin production in the presence of low serum iron levels. High hepcidin levels result in less iron being absorbed from the bowel than is necessary for erythropoiesis. Therefore, patients with matriptase-2 deficiency respond poorly to oral iron treatment and have to be treated with intravenous iron.

Background: The narrow host range of Mycobacterium leprae and the fact that it is refractory to growth in culture has limited research on and the biologic understanding of leprosy. Host genetic factors are thought to influence susceptibility to infection as well as disease progression., Methods: We performed a two-stage genomewide association study by genotyping 706 patients and 1225 controls using the Human610-Quad BeadChip (Illumina). We then tested three independent replication sets for an association between the presence of leprosy and 93 single-nucleotide polymorphisms (SNPs) that were most strongly associated with the disease in the genomewide association study. Together, these replication sets comprised 3254 patients and 5955 controls. We also carried out tests of heterogeneity of the associations (or lack thereof) between these 93 SNPs and disease, stratified according to clinical subtype (multibacillary vs. paucibacillary)., Results: We observed a significant association (P<1.00x10(-10)) between SNPs in the genes CCDC122, C13orf31, NOD2, TNFSF15, HLA-DR, and RIPK2 and a trend toward an association (P=5.10x10(-5)) with a SNP in LRRK2. The associations between the SNPs in C13orf31, LRRK2, NOD2, and RIPK2 and multibacillary leprosy were stronger than the associations between these SNPs and paucibacillary leprosy., Conclusions: Variants of genes in the NOD2-mediated signaling pathway (which regulates the innate immune response) are associated with susceptibility to infection with M. leprae., (2009 Massachusetts Medical Society)

Context: Obesity and iron deficiency are two of the most common nutritional disorders worldwide. Several studies found higher rates of iron deficiency in obese than in normal-weight children. Hepcidin represents the main inhibitor of intestinal iron absorption, and its expression is increased in adipose tissue of obese patients. Leptin is able, in vitro, to raise hepcidin expression., Objectives: Aims of this work were 1) to assess the association between poor iron status and obesity, 2) to investigate whether iron homeostasis of obese children may be modulated by serum hepcidin variations, and 3) to assess the potential correlation between leptin and serum hepcidin variations., Methods: Iron status and absorption as well as hepcidin, leptin, and IL-6 levels were studied in 60 obese children and in 50 controls., Results: Obese children showed lower iron and transferrin saturation (both P < 0.05) and higher hepcidin levels (P = 0.004) compared with controls. A direct correlation between hepcidin and obesity degree (P = 0.0015), and inverse correlations between hepcidin and iron (P = 0.04), hepcidin and transferrin saturation (P = 0.005), and hepcidin and iron absorption (P = 0.003) were observed. A correlation between leptin and hepcidin (P = 0.006) has been found. The correlation remained significant when adjusted for body mass index, sex, pubertal stage, and IL-6 values., Conclusions: We propose that in obese patients, increased hepcidin production, at least partly leptin mediated, represents the missing link between obesity and disrupted iron metabolism.

Amazon forests are a key but poorly understood component of the global carbon cycle. If, as anticipated, they dry this century, they might accelerate climate change through carbon losses and changed surface energy balances. We used records from multiple long-term monitoring plots across Amazonia to assess forest responses to the intense 2005 drought, a possible analog of future events. Affected forest lost biomass, reversing a large long-term carbon sink, with the greatest impacts observed where the dry season was unusually intense. Relative to pre-2005 conditions, forest subjected to a 100-millimeter increase in water deficit lost 5.3 megagrams of aboveground biomass of carbon per hectare. The drought had a total biomass carbon impact of 1.2 to 1.6 petagrams (1.2 x 10(15) to 1.6 x 10(15) grams). Amazon forests therefore appear vulnerable to increasing moisture stress, with the potential for large carbon losses to exert feedback on climate change.

Home-based palliative care (hospice) services require comprehensive and fully integrated information systems to develop and manage the various aspects of their business, incorporating client data and management information. These systems assist in maintaining the quality of client care as well as improved management efficiencies. This article reports on a large not-for-profit home-based palliative care service in Australia, which embarked on a project to develop an electronic data management system specifically designed to meet the needs of the palliative care sector. This web-based client information management system represents a joint venture between the organization and a commercial company and has been a very successful project.

Objective: This study evaluated the validity of prescriber, patient, and research assistant ratings of adherence to prescribed oral antipsychotic medication among outpatients with schizophrenia or schizoaffective disorder in comparison with electronic monitoring., Methods: Adult outpatients with schizophrenia (N=35) or schizoaffective disorder (N=26) received adherence assessments via electronically monitored medication vial caps as well as by monthly prescriber, patient, and research assistant report for up to six months., Results: Electronic monitoring detected greater nonadherence rates (57%) than either prescribers (7%) or patients (5%), though the research assistant ratings were 54%. No directional bias was found between electronic monitoring and assignment of adherence by research assistants, although disagreement occurred in 36% of cases., Conclusions: Both patients and prescribers grossly overestimated medication adherence, which may interfere with or reduce the effectiveness of diligent medication management.

Considering that a wide access to updated and relevant data is a key point for livestock development and research improvement in tropics, The PigTrop web site (http://pigtrop.cirad.fr) is dedicated to pig production and pork commodity chains in developing countries. It mainly addresses stakeholders involved in the pig commodity chain, but also researchers, students, or development agencies with an interest in tropical pig breeding. It is run by the French Agricultural Research Centre for International Development (CIRAD).

Large-scale gene discovery has been performed for the grass fungal endophytes Neotyphodium coenophialum, Neotyphodium lolii, and Epichloë festucae. The resulting sequences have been annotated by comparison with public DNA and protein sequence databases and using intermediate gene ontology annotation tools. Endophyte sequences have also been analysed for the presence of simple sequence repeat and single nucleotide polymorphism molecular genetic markers. Sequences and annotation are maintained within a MySQL database that may be queried using a custom web interface. Two cDNA-based microarrays have been generated from this genome resource. They permit the interrogation of 3806 Neotyphodium genes (Nchip microarray), and 4195 Neotyphodium and 920 Epichloë genes (EndoChip microarray), respectively. These microarrays provide tools for high-throughput transcriptome analysis, including genome-specific gene expression studies, profiling of novel endophyte genes, and investigation of the host grass-symbiont interaction. Comparative transcriptome analysis in Neotyphodium and Epichloë was performed.

Despite research findings that lesbigays value, want, and use counseling services, some counselors report they are not adequately prepared to work with the lesbigay population. Lesbigay students have reported biases and discrimination in their programs. Research has found that some mental health professionals engage in a number of harmful practices when working with lesbigay clients. These findings challenge counselor education programs to find better ways of infusing lesbigay issues into their curricula. This article discusses how lesbigay issues might be infused into the counseling research classroom in ways that provide students the opportunity to think critically; learn about research design and ethics; expand their levels of tolerance; develop a deeper appreciation of the work involved in doing research; and see the power of research to change the course of history.

A previous study by Phillips et al. of changes in the biomass of permanent sample plots in Amazonian forests was used to infer the presence of a regional carbon sink. However, these results generated a vigorous debate about sampling and methodological issues. Therefore we present a new analysis of biomass change in old-growth Amazonian forest plots using updated inventory data. We find that across 59 sites, the above-ground dry biomass in trees that are more than 10 cm in diameter (AGB) has increased since plot establishment by 1.22 +/- 0.43 Mg per hectare per year (ha(-1) yr(-1), where 1 ha = 10(4) m2), or 0.98 +/- 0.38 Mg ha(-1) yr(-1) if individual plot values are weighted by the number of hectare years of monitoring. This significant increase is neither confounded by spatial or temporal variation in wood specific gravity, nor dependent on the allometric equation used to estimate AGB. The conclusion is also robust to uncertainty about diameter measurements for problematic trees: for 34 plots in western Amazon forests a significant increase in AGB is found even with a conservative assumption of zero growth for all trees where diameter measurements were made using optical methods and/or growth rates needed to be estimated following fieldwork. Overall, our results suggest a slightly greater rate of net stand-level change than was reported by Phillips et al. Considering the spatial and temporal scale of sampling and associated studies showing increases in forest growth and stem turnover, the results presented here suggest that the total biomass of these plots has on average increased and that there has been a regional-scale carbon sink in old-growth Amazonian forests during the previous two decades.

The flavin-containing monooxygenases (FMOs) are important for the disposition of a variety of toxicants, therapeutics, and dietary components. Although FMO1 is the dominant isoform in fetal liver and adult kidney and intestine and despite up to a 10-fold intersubject variation in expression, a paucity of information is available on FMO1 genetic variability. To address this issue, 24 samples from the Coriell DNA Polymorphism Discovery Resource Panel were sequenced revealing 10 common single nucleotide polymorphisms (SNPs): four located upstream of the structural gene; three within exonic sequences; one within the intron 1 splice donor site; and two with the 3'-untranslated region. Six of these variants are novel. Compared with other FMO loci within the chromosome 1q23-25 cluster, FMO1 seems more highly conserved. Of the identified FMO1 SNPs, only a C>A transversion 9536 base pairs upstream of the exon 2 ATG start codon (g.-9536C>A) would likely affect function, because it lies within the conserved core binding sequence for the yin yang 1 (YY1) transcription factor. Electrophoretic mobility shift assays demonstrated that the g.-9536C>A transversion eliminated YY1 binding. Furthermore, data from transient expression assays in HepG2 cells suggested this SNP could account for a 2- to 3-fold loss of FMO1 promoter activity. Genotype analysis revealed a g.-9,536A allele (FMO1*6) frequency of 13 and 11% in African- and northern European-Americans, respectively, but a significantly higher frequency of 30% in Hispanic-Americans. Thus, the FMO1*6 variant may account for some of the observed interindividual variation in FMO1 expression.

Ecological orthodoxy suggests that old-growth forests should be close to dynamic equilibrium, but this view has been challenged by recent findings that neotropical forests are accumulating carbon and biomass, possibly in response to the increasing atmospheric concentrations of carbon dioxide. However, it is unclear whether the recent increase in tree biomass has been accompanied by a shift in community composition. Such changes could reduce or enhance the carbon storage potential of old-growth forests in the long term. Here we show that non-fragmented Amazon forests are experiencing a concerted increase in the density, basal area and mean size of woody climbing plants (lianas). Over the last two decades of the twentieth century the dominance of large lianas relative to trees has increased by 1.7-4.6% a year. Lianas enhance tree mortality and suppress tree growth, so their rapid increase implies that the tropical terrestrial carbon sink may shut down sooner than current models suggest. Predictions of future tropical carbon fluxes will need to account for the changing composition and dynamics of supposedly undisturbed forests.

Novel fluorescent oligonucleotides that contain a 3' minor groove binding group (MGB) hybridize to single-stranded targets with increased sequence-specificity compared to ordinary DNA probes. This reduces non-specific probe hybridization and results in low background fluorescence during the 5' nuclease PCR assay (TaqMan, Applied Biosystems, Foster City, CA). We developed a method for closed-tube genotyping using two allele-specific MGB probes labeled with different fluorophores in one reaction. After PCR, tubes were transported to a fluorescence plate-reader for analysis of fluorescence. Common spreadsheet software was used for automated genotype assignment. As an example, DNA samples from 172 hemochromatosis patients were selected and tested for molecular defects in the HFE gene, i.e., mutations in codon 63 and 282. Tight genotype clusters were observed for both codons and results with MGB probes were identical to conventional genotyping (PCR + restriction-fragment-length-polymorphism). We show that this fast and easy method can be used for large-scale (high-throughput) genetic studies but also for routine molecular diagnostics without post-PCR manipulation of amplicons or the need for real-time quantitative PCR machines. Hum Mutat 19:554-559, 2002., (Copyright 2002 Wiley-Liss, Inc.)

The persistence of neural stem cells into adulthood has been an area of intense investigation in recent years. There is limited knowledge about how an acquired brain injury might affect the ability of neural precursor cells to proliferate and repopulate injured areas. In the present study we utilize a controlled cortical impact model of traumatic brain injury in adult mice and subsequent BrdU labeling to demonstrate that there is significant proliferation of neural precursors in response to traumatic brain injury in areas both proximal and distal to the injury site. The fate of the proximal proliferation is almost exclusively astrocytic at 60-days post injury and demonstrates that newly generated cells make up much of the astrogliotic scar. Moreover, in areas more distal from the injury site, neurogenesis occurs within the granular layer of the dentate gyrus at a level more than five-fold greater than in controls. These data demonstrate that neural proliferation plays key roles in the remodeling that occurs after traumatic brain injury and suggests a mechanism as to how functional recovery after traumatic brain injuries continues to occur long after the injury itself., (Copyright 2001 Wiley-Liss, Inc.)

N-myc is a transcription factor expressed in the developing metanephric kidney and other organs. In mice, complete disruption of the N-myc gene results in fetal death on the first day of renal organogenesis. In addition to the null N-myc allele, others have generated a hypomorphic N-myc allele. In this study, combinations of these mutant genes were used to demonstrate that reduction in N-myc protein levels correlate with fewer developing glomeruli and collecting ducts in embryonic kidney explants. Histological sections revealed that the mutant kidneys were hypoplastic with normal developing structures. The data indicate that the hypoplasia is due to a reduction in proliferation rather than an increase in apoptosis. Thus, N-myc loss causes a decrease in numbers of ureteric bud tips and developing glomeruli in explants and hypoplastic kidneys in vivo, in a dose-dependent manner., (Copyright 2000 Academic Press.)

The use of a Fast Track system in the emergency department is becoming increasingly popular in order to provide fast and efficient service to patients with minor emergencies. In this paper we describe the one-year results of our system staffed by nurse practitioners. During the first year of operation, a total of 4468 patients were seen in Fast Track. Approximately 28% of patients are triaged to Fast Track during its hours of operation. The average patient seen in Fast Track was ready for discharge 94.4 minutes after presentation. Fewer than 1% of patients required admission to the hospital. Overall, patients and medical staff were highly satisfied with the Fast Track system. Our experience demonstrates that nurse practitioners can effectively and efficiently staff a Fast Track in an academic emergency department.