401 research outputs found

    Estuary-associated syndrome in North Carolina: an occupational prevalence study.

    Get PDF
    Atlantic coast estuaries recently have experienced fish kills and fish with lesions attributed to Pfiesteria piscicida and related dinoflagellates. Human health effects have been reported from laboratory exposure and from a 1997 Maryland fish kill. North Carolina has recorded Pfiesteria-related fish kill events over the past decade, but human health effects from environmental exposure have not been systematically investigated or documented here. At the request of the state health agency, comprehensive examinations were conducted in a cross-sectional prevalence study of watermen working where Pfiesteria exposure may occur: waters where diseased or stressed fish were reported from June to September 1997, and where Pfiesteria had been identified in the past. Controls worked on unaffected waterways. The study was conducted 3 months after the last documented Pfiesteria-related fish kill. The goal was to document any persistent health effects from recent or remote contact with fish kills, fish with lesions, or affected waterways, using the 1997 U.S. Centers for Disease Control and Prevention case description for estuary-associated syndrome (EAS). Examinations included comprehensive medical, occupational, and environmental history, general medical, dermatologic, and neurologic examinations, vision testing, and neuropsychologic evaluations. Seventeen of 22 watermen working in affected waters and 11 of 21 in unaffected waters reported exposure to a fish kill or to fish with lesions. We found no pattern of abnormalities on medical, neurologic, neuropsychologic, or NES-2 evaluation. By history, one subject in each group met the EAS criteria, neither of whom had significant neuropsychological impairment when examined. Watermen from affected waterways had a significant reduction in visual contrast sensitivity (VCS) at the midspatial frequencies, but we did not identify a specific factor or exposure associated with this reduction. The cohorts did not differ in reported occupational exposure to solvents (qualitative) or to other neurotoxicants; however, exposure history was not sufficiently detailed to measure or control for solvent exposure. This small prevalence study in watermen, conducted 3 months after the last documented fish kill related to Pfiesteria, did not identify an increased risk of estuary-associated syndrome in those working on affected waterways. A significant difference between the estuary and ocean watermen was found on VCS, which could not be attributed to any specific factor or exposure. VCS may be affected by chemicals, drugs, alcohol, and several developmental and degenerative conditions; it has not been validated as being affected by known exposure to dinoflagellate secretions. VCS should be considered for inclusion in further studies, together with documentation or quantification of its potential confounders, to assess whether it has utility in relationship to dinoflagellate exposure

    Laser-sintered thin films of doped SiGe nanoparticles

    Full text link
    We present a study of the morphology and the thermoelectric properties of short-pulse laser-sintered (LS) nanoparticle (NP) thin films, consisting of SiGe alloy NPs or composites of Si and Ge NPs. Laser-sintering of spin-coated NP films in vacuum results in a macroporous percolating network with a typical thickness of 300 nm. The Seebeck coefficient is independent of the sintering process and typical for degenerate doping. The electrical conductivity of LS films rises with increasing temperature, best described by a power-law and influenced by two-dimensional percolation effects.Comment: 4 pages, 4 figure

    A comparative analysis of the information content in long and short SAGE libraries

    Get PDF
    BACKGROUND: Serial Analysis of Gene Expression (SAGE) is a powerful tool to determine gene expression profiles. Two types of SAGE libraries, ShortSAGE and LongSAGE, are classified based on the length of the SAGE tag (10 vs. 17 basepairs). LongSAGE libraries are thought to be more useful than ShortSAGE libraries, but their information content has not been widely compared. To dissect the differences between these two types of libraries, we utilized four libraries (two LongSAGE and two ShortSAGE libraries) generated from the hippocampus of Alzheimer and control samples. In addition, we generated two additional short SAGE libraries, the truncated long SAGE libraries (tSAGE), from LongSAGE libraries by deleting seven 5' basepairs from each LongSAGE tag. RESULTS: One problem that occurred in the SAGE study is that individual tags may have matched to multiple different genes – due to the short length of a tag. We found that the LongSAGE tag maps up to 15 UniGene clusters, while the ShortSAGE and tSAGE tags map up to 279 UniGene clusters. Both long and short SAGE libraries exhibit a large number of orphan tags (no gene information in UniGene), implying the limitation of the UniGene database. Among 100 orphan LongSAGE tags, the complete sequences (17 basepairs) of nine orphan tags match to 17 genomic sequences; four of the orphan tags match to a single genomic sequence. Our data show the potential to resolve 4–9% of orphan LongSAGE tags. Finally, among 400 tSAGE tags showing significant differential expression between AD and control, 79 tags (19.8%) were derived from multiple non-significant LongSAGE tags, implying the false positive results. CONCLUSION: Our data show that LongSAGE tags have high specificity in gene mapping compared to ShortSAGE tags. LongSAGE tags show an advantage over ShortSAGE in identifying novel genes by BLAST analysis. Most importantly, the chances of obtaining false positive results are higher for ShortSAGE than LongSAGE libraries due to their specificity in gene mapping. Therefore, it is recommended that the number of corresponding UniGene clusters (gene or ESTs) of a tag for prioritizing the significant results be considered

    Human in vitro reporter model of neuronal development and early differentiation processes

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>During developmental and adult neurogenesis, doublecortin is an early neuronal marker expressed when neural stem cells assume a neuronal cell fate. To understand mechanisms involved in early processes of neuronal fate decision, we investigated cell lines for their capacity to induce expression of doublecortin upon neuronal differentiation and develop <it>in vitro </it>reporter models using doublecortin promoter sequences.</p> <p>Results</p> <p>Among various cell lines investigated, the human teratocarcinoma cell line NTERA-2 was found to fulfill our criteria. Following induction of differentiation using retinoic acid treatment, we observed a 16-fold increase in doublecortin mRNA expression, as well as strong induction of doublecortin polypeptide expression. The acquisition of a neuronal precursor phenotype was also substantiated by the establishment of a multipolar neuronal morphology and expression of additional neuronal markers, such as Map2, βIII-tubulin and neuron-specific enolase. Moreover, stable transfection in NTERA-2 cells of reporter constructs encoding fluorescent or luminescent genes under the control of the doublecortin promoter allowed us to directly detect induction of neuronal differentiation in cell culture, such as following retinoic acid treatment or mouse Ngn2 transient overexpression.</p> <p>Conclusion</p> <p>Induction of doublecortin expression in differentiating NTERA-2 cells suggests that these cells accurately recapitulate some of the very early events of neuronal determination. Hence, the use of reporter genes under the control of the doublecortin promoter in NTERA-2 cells will help us to investigate factors involved early in the course of neuronal differentiation processes. Moreover the ease to detect the induction of a neuronal program in this model will permit to perform high throughput screening for compounds acting on the early neuronal differentiation mechanisms.</p

    Generation of NSE-MerCreMer Transgenic Mice with Tamoxifen Inducible Cre Activity in Neurons

    Get PDF
    To establish a genetic tool for conditional deletion or expression of gene in neurons in a temporally controlled manner, we generated a transgenic mouse (NSE-MerCreMer), which expressed a tamoxifen inducible type of Cre recombinase specifically in neurons. The tamoxifen inducible Cre recombinase (MerCreMer) is a fusion protein containing Cre recombinase with two modified estrogen receptor ligand binding domains at both ends, and is driven by the neural-specific rat neural specific enolase (NSE) promoter. A total of two transgenic lines were established, and expression of MerCreMer in neurons of the central and enteric nervous systems was confirmed. Transcript of MerCreMer was detected in several non-neural tissues such as heart, liver, and kidney in these lines. In the background of the Cre reporter mouse strain Rosa26R, Cre recombinase activity was inducible in neurons of adult NSE-MerCreMer mice treated with tamoxifen by intragastric gavage, but not in those fed with corn oil only. We conclude that NSE-MerCreMer lines will be useful for studying gene functions in neurons for the conditions that Cre-mediated recombination resulting in embryonic lethality, which precludes investigation of gene functions in neurons through later stages of development and in adult

    Izloženost alergenima plijesni u unutarnjem okolišu

    Get PDF
    Humid indoor environments may be colonised by allergenic fi lamentous microfungi (moulds), Aspergillus spp., Penicillium spp., Cladosporium spp., and Alternaria spp. in particular. Mould-induced respiratory diseases are a worldwide problem. In the last two decades, mould allergens and glucans have been used as markers of indoor exposure to moulds. Recently, mould allergens Alt a 1 (Alternaria alternata) and Asp f 1 (Aspergillus fumigatus) have been analysed in various environments (residential and occupational) with enzyme-linked immunosorbent assays, which use monoclonal or polyclonal antibodies. Household Alt a 1 and Asp f 1 levels were usually under the limit of the method detection. By contrast, higher levels of mould allergens were found in environments with high levels of bioaerosols such as poultry farms and sawmills. Data on allergen Alt a 1 and Asp f 1 levels in agricultural settings may provide information on possible colonisation of respective moulds and point out to mould-related diseases in occupants.Vlažni, unutarnji prostori mogu biti kolonizirani alergogenim, filamentoznim mikrogljivicama (plijesni) uglavnom rodova Aspergillus, Penicillium, Cladosporium i Alternaria. Respiratorne bolesti uzrokovane plijesnima zdravstveni su problem diljem svijeta. U posljednja dva desetljeća, neki sastavni dijelovi plijesni kao alergeni i glukan rabe se kao pokazatelji izloženosti plijesni u unutarnjem okolišu. Nedavno su alergeni plijesni Alt a 1 (Alternaria alternata) i Asp f 1 (Aspergillus fumigatus) određivani u različitom okolišu (kućnom i profesionalnom) enzim-imunokemijskom metodom koja rabi monoklonska ili poliklonska antitijela. Razina Alt a 1 i Asp f 1 u kućnoj prašini ispod je granice detekcije. Nasuprot tomu, alergeni plijesni su određeni u okolišu s visokom razinom bioaerosola kao peradarnici i pilane. Razine alergena Alt a 1 i Asp f 1 u nekim poljoprivrednim objektima pružaju informaciju o mogućoj kolonizaciji plijesnima, što upućuje na moguće zdravstvene učinke kod zaposlenika

    Biomarkers of Therapeutic Response in the IL-23 Pathway in Inflammatory Bowel Disease

    Get PDF
    OBJECTIVES: Interleukin-23 (IL-23) has emerged as a new therapeutic target for the treatment of inflammatory bowel disease (IBD). As biomarkers of disease state and treatment efficacy are becoming increasingly important in drug development, we sought to identify efficacy biomarkers for anti-IL-23 therapy in Crohn's disease (CD). METHODS: Candidate IL-23 biomarkers, downstream of IL-23 signaling, were identified using shotgun proteomic analysis of feces and colon lavages obtained from a short-term mouse IBD model (anti-CD40 Rag2(-/-)) treated preventively with monoclonal antibodies (mAbs) to the IL-23 receptor (IL-23R). The biomarkers were then measured in an IBD T-cell transfer model treated therapeutically with a mAb to IL-23 (p19), confirming their association with IBD. To assess the clinical relevance of these markers, we assessed their concentrations in clinical serum, colon tissue, and feces from CD patients. RESULTS: We identified 57 proteins up or downregulated in diseased animals that returned to control values when the mice were treated with mAbs to IL-23R. Among those, S100A8, S100A9, regenerating protein 3β (REG), REG3γ, lipocalin 2 (LCN2), deleted in malignant tumor 1 (DMBT1), and macrophage migration inhibitory factor (MIF) mRNA levels correlated with disease score and dose titration of mAbs to IL-23R or IL-23(p19). All biomarkers, except DMBT1, were also downregulated after therapeutic administration of mAbs to IL-23(p19) in a T-cell transfer IBD mouse model. In sera from CD patients, we confirmed a significant upregulation of S100A8/A9 (43%), MIF (138%), pancreatitis-associated protein (PAP, human homolog of REG3β/γ; 49%), LCN2 (520%), and CCL20 (1280%), compared with control samples, as well as a significant upregulation of S100A8/A9 (887%), PAP (401%), and LCN2 (783%) in human feces from CD patients compared with normal controls. CONCLUSIONS: These studies identify multiple protein biomarkers downstream of IL-23 that could be valuable tools to assess the efficacy of this new therapeutic agent.Clinical and Translational Gastroenterology (2012) 3, e10; doi:10.1038/ctg.2012.2; published online 16 February 2012

    What People Believe about How Memory Works: A Representative Survey of the U.S. Population

    Get PDF
    Incorrect beliefs about the properties of memory have broad implications: The media conflate normal forgetting and inadvertent memory distortion with intentional deceit, juries issue verdicts based on flawed intuitions about the accuracy and confidence of testimony, and students misunderstand the role of memory in learning. We conducted a large representative telephone survey of the U.S. population to assess common beliefs about the properties of memory. Substantial numbers of respondents agreed with propositions that conflict with expert consensus: Amnesia results in the inability to remember one's own identity (83% of respondents agreed), unexpected objects generally grab attention (78%), memory works like a video camera (63%), memory can be enhanced through hypnosis (55%), memory is permanent (48%), and the testimony of a single confident eyewitness should be enough to convict a criminal defendant (37%). This discrepancy between popular belief and scientific consensus has implications from the classroom to the courtroom

    Increased Frequencies of Th22 Cells as well as Th17 Cells in the Peripheral Blood of Patients with Ankylosing Spondylitis and Rheumatoid Arthritis

    Get PDF
    <div><h3>Background</h3><p>T-helper (Th) 22 is involved in the pathogenesis of inflammatory diseases. The roles of Th22 cells in the pathophysiological of ankylosing spondylitis (AS) and rheumatoid arthritis (RA) remain unsettled. So we examined the frequencies of Th22 cells, Th17 cells and Th1 cells in peripheral blood (PB) from patients with AS and patients with RA compared with both healthy controls as well as patients with osteoarthritis.</p> <h3>Design and Methods</h3><p>We studied 32 AS patients, 20 RA patients, 10 OA patients and 20 healthy controls. The expression of IL-22, IL-17 and IFN-γ were examined in AS, RA, OA patients and healthy controls by flow cytometry. Plasma IL-22 and IL-17 levels were examined by enzyme-linked immunosorbent assay.</p> <h3>Results</h3><p>Th22 cells, Th17 cells and interleukin-22 were significantly elevated in AS and RA patients compared with OA patients and healthy controls. Moreover, Th22 cells showed positive correlation with Th17 cells as well as interleukin-22 in AS and RA patients. However, positive correlation between IL-22 and Th17 cells was only found in AS patients not in RA patients. In addition, the percentages of both Th22 cells and Th17 cells correlated positively with disease activity only in RA patients not in AS patients.</p> <h3>Conclusions</h3><p>The frequencies of both Th22 cells and Th17 cells were elevated in PB from patients with AS and patients with RA. These findings suggest that Th22 cells and Th17 cells may be implicated in the pathogenesis of AS and RA, and Th22 cells and Th17 cells may be reasonable cellular targets for therapeutic intervention.</p> </div
    corecore