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61.
Wendy Kuhn Rachel Gambino Nader Al-Awadhi Mohammed Talaat Balba James Dragun 《Soil & Sediment Contamination》1998,7(6):801-806
This laboratory study measured growth of one plant species, Lycopersicon esculentum Big Girl (tomato), that is sensitive to the presence of soil contamination, in Kuwait soil amended with crude-oil-contaminated soil. Germinated tomato seeds were placed in containers with soil containing 0, 0.12, 0.24, 0.36, 0.48, 0.60, 1.2, and 2.4% crude oil and were grown in an indoor growth chamber. Plants grew in Kuwait soil containing up to 0.36% crude oil; however, growth and fruit production were compromised at crude oil concentrations greater than 0.12% when compared with control plants. Plants did not grow in Kuwait soil amended with 0.48% crude oil or higher. 相似文献
62.
Christine Jacomet Clotilde Allavena Fleur Peyrol Bruno Pereira Laurence Morand Joubert Haleh Bagheri Laurent Cotte Rodolphe Garaffo Laurent Gerbaud Pierre Dellamonica 《PloS one》2015,10(2)
BackgroundIn the interest of cost effectiveness, switching antiretroviral brand name medications to generics is recommended in France since 2013. The study objective was to evaluate the perception of generics per se and antiretroviral generics in HIV-infected patients and their hospital physiciansConclusionsAcceptability of antiretroviral generics in this French population was mostly dictated by the patient’s and physician’s knowledge and use of generics overall. It should be improved with an efficient information of both patients and physicians. 相似文献
63.
Christian Dejaco Bastian Oppl Paul Monach David Cuthbertson Simon Carette Gary Hoffman Nader Khalidi Curry Koening Carol Langford Kathleen McKinnon-Maksimowicz Philip Seo Ulrich Specks Steven Ytterberg Peter A. Merkel Jochen Zwerina 《PloS one》2015,10(3)
Introduction
Previous studies suggest a role for eotaxin-3, TARC/CCL17 and IgG4 in newly- diagnosed patients with eosinophilic granulomatosis with polyangiitis (EGPA, Churg-Strauss) with highly active disease. The role of these biomarkers in relapsing disease is unclear.Methods
Serum levels of TARC/CCL17, eotaxin-3, IgG4, and IgG4/IgG ratio were determined in serum samples from a longitudinal cohort of patients with EGPA (105 visits of 25 patients). Epidemiological, clinical and laboratory data were available for all visits.Results
At the first visit, 80% of patients were using glucocorticoids and 68% additional immunosuppressive drugs. Disease flares were seen at 18 visits. The median BVAS and BVAS/WG scores at time of relapse were 4 and 2, respectively. None of the biomarkers tested were useful to discriminate between active disease and remission. Patients treated with prednisone had lower eotaxin-3 and eosinophil levels compared to patients not taking glucocorticoids irrespective of disease activity. Use of immunosuppressive agents was not associated with biomarker levels.Conclusions
Serum levels of TARC/CCL17, eotaxin-3, IgG4, and IgG4/IgG ratio do not clearly differentiate active and inactive disease in established EGPA. Defining biomarkers in EGPA remains a challenge especially during times of glucocorticoid use. 相似文献64.
Carolina Ganss Adrian Lussi Anne Peutzfeldt Nader Naguib Attia Nadine Schlueter 《PloS one》2015,10(6)
For preventing erosive wear in dentine, coating with adhesives has been suggested as an alternative to fluoridation. However, clinical studies have revealed limited efficacy. As there is first evidence that Sn2+ increases bond strength of the adhesive Clearfil SE (Kuraray), the aim of the present study was to investigate whether pre-treatment with different Sn2+/F− solutions improves the durability of Clearfil SE coatings. Dentine samples (eight groups, n=16/group) were freed of smear layer (0.5% citric acid, 10 s), treated (15 s) either with no solution (control), aminefluoride (AmF, 500 ppm F−, pH 4.5), SnCl2 (800/1600 ppm Sn2+; pH 1.5), SnCl2/AmF (500 ppm F−, 800 ppm Sn2+, pH 1.5/3.0/4.5), or Elmex Erosion Protection Rinse (EP, 500 ppm F−, 800 ppm Sn2+, pH 4.5; GABA International), then rinsed with water (15 s) and individually covered with Clearfil SE. Subsequently the specimens were subjected to an erosion/abrasion protocol consisting of 1320 cycles of immersion in 0.5% citric acid (5°C/55°C; 2 min) and automated brushing (15 s, 200 g, NaF-toothpaste, RDA 80). As the coatings proved stable up to 1320 cycles, 60 modified cycles (brushing time 30 min/cycle) were added. Wear was measured profilometrically. After SnCl2/AmF, pH 4.5 or EP pre-treatment all except one coating survived. In the other groups, almost all coatings were lost and there was no significant difference to the control group. Pre-treatment with a Sn2+/F− solution at pH 4.5 seems able to improve the durability of adhesive coatings, rendering these an attractive option in preventing erosive wear in dentine. 相似文献
65.
Ernesto Maddaloni Nader Lessan Alia Al Tikriti Raffaella Buzzetti Paolo Pozzilli Maha T. Barakat 《PloS one》2015,10(8)
Aims
To describe and to characterize clinical features of latent autoimmune diabetes in adults (LADA) compared to type 1 and type 2 diabetes in the UAE.Methods
In this cross-sectional study a dataset including 18,101 subjects with adult-onset (>30 years) diabetes was accessed. 17,072 subjects fulfilled the inclusion/exclusion criteria. Data about anthropometrics, demographics, autoantibodies to Glutamic Acid Decarboxylase (GADA) and to Islet Antigen 2 (anti-IA2), HbA1c, cholesterol and blood pressure were extracted. LADA was diagnosed according to GADA and/or anti-IA2 positivity and time to insulin therapy.Results
437 (2.6%) patients were identified as LADA and 34 (0.2%) as classical type 1 diabetes in adults. Mean age at diagnosis, BMI, waist circumference, systolic blood pressure and HbA1c significantly differed between, LADA, type 2 and type 1 diabetes, LADA showing halfway features between type 2 and type 1 diabetes. A decreasing trend for age at diagnosis and waist circumference was found among LADA subjects when subdivided by positivity for anti-IA2, GADA or for both antibodies (p=0.013 and p=0.011 for trend, respectively). There was a gradual downward trend in autoantibody titre in LADA subjects requiring insulin within the first year from diagnosis to subjects not requiring insulin after 10 years of follow-up (p<0.001).Conclusions
This is the first study describing the clinical features of LADA in the UAE, which appear to be different from both type 1 and type 2 diabetes. Furthermore, we showed that the clinical phenotype of LADA is dependent on different patterns of antibody positivity, influencing the time to insulin requirement. 相似文献66.
The cognitive profile and measured intellectual level vary according to assessment tools in children on the autism spectrum, much more so than in typically developing children. The recent inclusion of intellectual functioning in the diagnostic process for autism spectrum disorders leads to the crucial question on how to assess intelligence in autism, especially as some tests and subtests seem more sensitive to certain neurodevelopmental conditions. Our first aim was to examine the cognitive profile on the current version of the most widely used test, the Wechsler Intelligence Scales for Children (WISC-IV), for a homogenous subgroup of children on the autism spectrum, i.e. corresponding to DSM-IV diagnosis of “autism”. The second aim was to compare cognitive profiles obtained on the third edition versus 4th edition of WISC, in order to verify whether the WISC-IV yields a more distinctive cognitive profile in autistic children. The third aim was to examine the impact of the WISC-IV on the cognitive profile of another subgroup, children with Asperger’s Syndrome. 51 autistic, 15 Asperger and 42 typically developing children completed the WISC-IV and were individually matched to children who completed the WISC-III. Divergent WISC-IV profiles were observed despite no significant intelligence quotient difference between groups. Autistic children scored significantly higher on the Perceptual Reasoning Index than on the Verbal Comprehension Index, a discrepancy that nearly tripled in comparison to WISC-III results. Asperger children scored higher on the VCI than on other indexes, with the lowest score found on the Processing Speed Index. WISC-IV cognitive profiles were consistent with, but more pronounced than WISC-III profiles. Cognitive profiles are a valuable diagnostic tool for differential diagnosis, keeping in mind that children on the autism spectrum might be more sensitive to the choice of subtests used to assess intelligence. 相似文献
67.
Parameters of the two-parameter logistic model are generally estimated via the expectation-maximization algorithm, which improves initial values for all parameters iteratively until convergence is reached. Effects of initial values are rarely discussed in item response theory (IRT), but initial values were recently found to affect item parameters when estimating the latent distribution with full non-parametric maximum likelihood. However, this method is rarely used in practice. Hence, the present study investigated effects of initial values on item parameter bias and on recovery of item characteristic curves in BILOG-MG 3, a widely used IRT software package. Results showed notable effects of initial values on item parameters. For tighter convergence criteria, effects of initial values decreased, but item parameter bias increased, and the recovery of the latent distribution worsened. For practical application, it is advised to use the BILOG default convergence criterion with appropriate initial values when estimating the latent distribution from data. 相似文献
68.
Komal Sodhi Nitin Puri Gaia Favero Sarah Stevens Charles Meadows Nader G. Abraham Rita Rezzani Hayden Ansinelli Edward Lebovics Joseph I. Shapiro 《PloS one》2015,10(6)
Background
Oxidative stress underlies the etiopathogenesis of nonalcoholic fatty liver disease (NAFLD), obesity and cardiovascular disease (CVD). Heme Oxygenase-1 (HO-1) is a potent endogenous antioxidant gene that plays a key role in decreasing oxidative stress. Sirtuin1 (SIRT1) belongs to the family of NAD-dependent de-acyetylases and is modulated by cellular redox.Hypothesis
We hypothesize that fructose-induced obesity creates an inflammatory and oxidative environment conducive to the development of NAFLD and metabolic syndrome. The aim of this study is to determine whether HO-1 acts through SIRT1 to form a functional module within hepatocytes to attenuate steatohepatitis, hepatic fibrosis and cardiovascular dysfunction.Methods and Results
We examined the effect of fructose, on hepatocyte lipid accumulation and fibrosis in murine hepatocytes and in mice fed a high fructose diet in the presence and absence of CoPP, an inducer of HO-1, and SnMP, an inhibitor of HO activity. Fructose increased oxidative stress markers and decreased HO-1 and SIRT1 levels in hepatocytes (p<0.05). Further fructose supplementation increased FAS, PPARα, pAMPK and triglycerides levels; CoPP negated this increase. Concurrent treatment with CoPP and SIRT1 siRNA in hepatocytes increased FAS, PPARα, pAMPK and triglycerides levels suggesting that HO-1 is upstream of SIRT1 and suppression of SIRT1 attenuates the beneficial effects of HO-1. A high fructose diet increased insulin resistance, blood pressure, markers of oxidative stress and lipogenesis along with fibrotic markers in mice (p<0.05). Increased levels of HO-1 increased SIRT1 levels and ameliorated fructose-mediated lipid accumulation and fibrosis in liver along with decreasing vascular dysfunction (p<0.05 vs. fructose). These beneficial effects of CoPP were reversed by SnMP.Conclusion
Taken together, our study demonstrates, for the first time, that HO-1 induction attenuates fructose-induced hepatic lipid deposition, prevents the development of hepatic fibrosis and abates NAFLD-associated vascular dysfunction; effects that are mediated by activation of SIRT1 gene expression. 相似文献69.
Bahareh Eftekharzadeh Javad Hamedi Fatemeh Mohammadipanah Fariba Khodagholi Nader Maghsoudi Hans Peter Klenk 《Applied microbiology and biotechnology》2010,86(6):1805-1811
Actinomycetes isolated from Iran soil habitats were tested for the capacity to produce compounds which can protect neurons
from cell death generated by oxidative stress in NT2 neurons. Confirmation of our initial hit was accomplished via the determination
of amyloid β level using the enzyme-linked immunosorbent assay test. The most interesting amyloid β formation inhibitor discovered
in our study was a secondary metabolite which was produced by strain HM45. This bioactive strain was identified as a strain
of Streptomyces antibioticus DSM 40234 using polyphasic approach. The strain HM45 was deposited in Deutsche Sammlung von Mikroorganismen und Zellkulturen
as S. antibioticus DSM 41955 and University of Tehran Microorganisms Sollection as S. antibioticus UTMC 00105. This work is the first report on efficiency of an actinomycete metabolite in prohibition of neurons death caused
by amyloid β formation. 相似文献
70.
Izabela M.D. Bastos Flávia Nader Motta Sébastien Charneau Jaime M. Santana Lionel Dubost Koen Augustyns Philippe Grellier 《Microbes and infection / Institut Pasteur》2010,12(6):457-466
Proteases play important roles in many biological processes of parasites, including their host interactions. In sleeping sickness, Trypanosoma brucei proteases released into the host bloodstream could hydrolyze host factors, such as hormones, contributing to the development of the disease's symptoms. In this study, we present the identification of the T. brucei prolyl oligopeptidase gene (poptb) and the characterization of its corresponding enzyme, POP Tb. Secondary structure predictions of POP Tb show a structural composition highly similar to other POPs. Recombinant POP Tb produced in E. coli was active and highly sensitive to inhibitors of Trypanosoma cruzi POP Tc80. These inhibitors, which prevent T. cruzi entry into non-phagocytic cells, arrested growth of the T. brucei bloodstream form in a dose-dependent manner. POP Tb hydrolyzes peptide hormones containing Pro or Ala at the P1 position at a slightly alkaline pH, and also cleaves type I collagen in vitro and native collagen present in rat mesentery. Furthermore, POP Tb is released into the bloodstream of T. brucei infected mice where it remains active. These data suggest that POP Tb might contribute to the pathogenesis of sleeping sickness. 相似文献