177 research outputs found
500,000 Years of Environmental History in Eastern Anatolia: The PALEOVAN Drilling Project
International Continental Scientific Drilling Program
(ICDP) drilled a complete succession of the lacustrine sediment
sequence deposited during the last ~500,000 years in
Lake Van, Eastern Anatolia (Turkey). Based on a detailed
seismic site survey, two sites at a water depth of up to 360 m
were drilled in summer 2010, and cores were retrieved from
sub-lake-floor depths of 140 m (Northern Basin) and 220 m
(Ahlat Ridge). To obtain a complete sedimentary section, the
two sites were multiple-cored in order to investigate the paleoclimate
history of a sensitive semi-arid region between the
Black, Caspian, and Mediterranean seas. Further scientific
goals of the PALEOVAN project are the reconstruction of
earthquake activity, as well as the temporal, spatial, and
compositional evolution of volcanism as reflected in the deposition
of tephra layers. The sediments host organic matter
from different sources and hence composition, which will be
unravelled using biomarkers. Pathways for migration of continental
and mantle-derived noble gases will be analyzed in
pore waters. Preliminary 40Ar/39Ar single crystal dating of
tephra layers and pollen analyses suggest that the Ahlat
Ridge record encompasses more than half a million years of
paleoclimate and volcanic/geodynamic history, providing
the longest continental record in the entire Near East to
date
NF-KappaB expression correlates with apoptosis and angiogenesis in clear cell renal cell carcinoma tissues
<p>Abstract</p> <p>Background</p> <p>Clear cell renal cell carcinoma (ccRCC) is the most frequently encountered tumor in the adult kidney. Many factors are known to take part in the development and progression of this tumor. Nuclear factor kappa B (NF-κB) is a family of the genes that includes five members acting in events such as inflammation and apoptosis. In this study, the role of NF-κB (p50 subunit) in ccRCC and its relation to angiogenesis and apoptosis were investigated.</p> <p>Methods</p> <p>Formalin-fixed and paraffin embedded tissue blocks from 40 patients with ccRCC were studied. Expressions of NF-κB (p50), VEGF, EGFR, bc1-2 and p53 were detected immunohistochemically. The relationship of NF-κB with these markers and clinicopathological findings were evaluated.</p> <p>Results</p> <p>The expression of NF-κB was detected in 35 (85%), VEGF in 37 (92.5%), EGFR in 38 (95%), bc1-2 in 33 (82.5%) and p53 in 13 (32.5%) of 40 ccRCC patients. Statistical analyses revealed a significant relation between NF-κB expression and VEGF (p = 0.001), EGFR (p = 0.004), bc1-2 (p = 0.010) and p53 (p = 0.037). There was no significant correlation between NF-κB and such parameters as tumor grade, stage, age and sex.</p> <p>Conclusion</p> <p>The results of this study indicated that in ccRCC cases NF-κB was associated with markers of angiogenesis and apoptosis such as VEGF, EGFR, bc1-2 and p53. In addition, the results did not only suggest a close relationship between NF-κB and VEGF, EGFR, bc1-2 and p53 in ccRCC, but also indicate that NF-κB was a potential therapeutic target in the treatment of ccRCC resistant to chemotherapy.</p
Molecular Pathogenesis and Therapy of Polycythemia Induced in Mice by JAK2 V617F
BACKGROUND: A somatic activating mutation (V617F) in the JAK2 tyrosine kinase was recently discovered in the majority of patients with polycythemia vera (PV), and some with essential thrombocythemia (ET) and chronic idiopathic myelofibrosis. However, the role of mutant JAK2 in disease pathogenesis is unclear. METHODS AND FINDINGS: We expressed murine JAK2 WT or V617F via retroviral bone marrow transduction/transplantation in the hematopoietic system of two different inbred mouse strains, Balb/c and C57Bl/6 (B6). In both strains, JAK2 V617F, but not JAK2 WT, induced non-fatal polycythemia characterized by increased hematocrit and hemoglobin, reticulocytosis, splenomegaly, low plasma erythropoietin (Epo), and Epo-independent erythroid colonies. JAK2 V617F also induced leukocytosis and neutrophilia that was much more prominent in Balb/c mice than in B6. Platelet counts were not affected in either strain despite expression of JAK2 V617F in megakaryocytes and markedly prolonged tail bleeding times. The polycythemia tended to resolve after several months, coincident with increased spleen and marrow fibrosis, but was resurrected by transplantation to secondary recipients. Using donor mice with mutations in Lyn, Hck, and Fgr, we demonstrated that the polycythemia was independent of Src kinases. Polycythemia and reticulocytosis responded to treatment with imatinib or a JAK2 inhibitor, but were unresponsive to the Src inhibitor dasatinib. CONCLUSIONS: These findings demonstrate that JAK2 V617F induces Epo-independent expansion of the erythroid lineage in vivo. The fact that the central erythroid features of PV are recapitulated by expression of JAK2 V617F argues that it is the primary and direct cause of human PV. The lack of thrombocytosis suggests that additional events may be required for JAK2 V617F to cause ET, but qualitative platelet abnormalities induced by JAK2 V617F may contribute to the hemostatic complications of PV. Despite the role of Src kinases in Epo signaling, our studies predict that Src inhibitors will be ineffective for therapy of PV. However, we provide proof-of-principle that a JAK2 inhibitor should have therapeutic effects on the polycythemia, and perhaps myelofibrosis and hemostatic abnormalities, suffered by MPD patients carrying the JAK2 V617F mutation
Psychometric properties of the Alcohol Use Disorders Identification Test (AUDIT) across cross-cultural subgroups, genders, and sexual orientations: Findings from the International Sex Survey (ISS)
© 2023 The Authors. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/bync-nd/4.0/).INTRODUCTION: Despite being a widely used screening questionnaire, there is no consensus on the most appropriate measurement model for the Alcohol Use Disorders Identification Test (AUDIT). Furthermore, there have been limited studies on its measurement invariance across cross-cultural subgroups, genders, and sexual orientations. AIMS: The present study aimed to examine the fit of different measurement models for the AUDIT and its measurement invariance across a wide range of subgroups by country, language, gender, and sexual orientation. METHODS: Responses concerning past-year alcohol use from the participants of the cross-sectional International Sex Survey were considered (N = 62,943; M age: 32.73; SD = 12.59). Confirmatory factor analysis, as well as measurement invariance tests were performed for 21 countries, 14 languages, three genders, and four sexual-orientation subgroups that met the minimum sample size requirement for inclusion in these analyses. RESULTS: A two-factor model with factors describing 'alcohol use' (items 1-3) and 'alcohol problems' (items 4-10) showed the best model fit across countries, languages, genders, and sexual orientations. For the former two, scalar and latent mean levels of invariance were reached considering different criteria. For gender and sexual orientation, a latent mean level of invariance was reached. CONCLUSIONS: In line with the two-factor model, the calculation of separate alcohol-use and alcohol-problem scores is recommended when using the AUDIT. The high levels of measurement invariance achieved for the AUDIT support its use in cross-cultural research, capable also of meaningful comparisons among genders and sexual orientations.Peer reviewe
The Tyrphostin Agent AG490 Prevents and Reverses Type 1 Diabetes in NOD Mice
<div><h3>Background</h3><p>Recent studies in the NOD (non-obese diabetic) mouse model of type 1 diabetes (T1D) support the notion that tyrosine kinase inhibitors have the potential for modulating disease development. However, the therapeutic effects of AG490 on the development of T1D are unknown.</p> <h3>Materials and Methods</h3><p>Female NOD mice were treated with AG490 (i.p, 1 mg/mouse) or DMSO starting at either 4 or 8 week of age, for five consecutive week, then once per week for 5 additional week. Analyses for the development and/or reversal of diabetes, insulitis, adoptive transfer, and other mechanistic studies were performed.</p> <h3>Results</h3><p>AG490 significantly inhibited the development of T1D (p = 0.02, p = 0.005; at two different time points). Monotherapy of newly diagnosed diabetic NOD mice with AG490 markedly resulted in disease remission in treated animals (n = 23) in comparision to the absolute inability (0%; 0/10, p = 0.003, Log-rank test) of DMSO and sustained eugluycemia was maintained for several months following drug withdrawal. Interestingly, adoptive transfer of splenocytes from AG490 treated NOD mice failed to transfer diabetes to recipient NOD.<em>Scid</em> mice. CD4 T-cells as well as bone marrow derived dendritic cells (BMDCs) from AG490 treated mice, showed higher expression of Foxp3 (p<0.004) and lower expression of co-stimulatory molecules, respectively. Screening of the mouse immune response gene arrary indicates that expression of costimulaotry molecule Ctla4 was upregulated in CD4+ T-cell in NOD mice treated with AG490, suggesting that AG490 is not a negative regulator of the immune system.</p> <h3>Conclusion</h3><p>The use of such agents, given their extensive safety profiles, provides a strong foundation for their translation to humans with or at increased risk for the disease.</p> </div
Abrogation of IL-6-mediated JAK signalling by the cyclopentenone prostaglandin 15d-PGJ2 in oral squamous carcinoma cells
Cyclopentenone 15-deoxy-Δ12,14-prostaglandin J2 (15d-PGJ2) exerts antineoplastic effects on various types of human cancer. We recently showed that treatment with 15d-PGJ2 induces apoptosis accompanied by downregulation of the oncogenic signal transducer and activator of transcription 3 (Stat3) signalling in human oral squamous cell carcinoma (SCC) cells. The current study examines the effects of 15d-PGJ2 on the epidermal growth factor receptor (EGFR) and Janus Kinase (JAK)-mediated signalling pathways. Inhibition of Stat3 by 15d-PGJ2 was abolished by exogenous stimulation with transforming growth factor alpha (TGF-α), but not interleukin 6 (IL-6), supporting a selective effect of 15d-PGJ2 on IL-6-mediated signalling. Importantly, 15d-PGJ2 selectively abrogated constitutive and IL-6-mediated JAK phosphorylation without affecting EGFR-activated levels. Moreover, the inhibitory effect of 15d-PGJ2 on JAK signalling required the reactive α,β-unsaturated carbon within the cyclopentenone ring. Targeting of JAK signalling using a specific JAK inhibitor also abolished Stat3 phosphorylation and resulted in apoptosis in oral SCC cells. Our findings provide the first evidence for 15d-PGJ2–mediated downregulation of constitutive and IL-6-induced JAK signalling in cancer and support that JAK inhibition and suppression of EGFR-independent Stat3 activation by 15d-PGJ2 represent a promising approach for induction of apoptosis in oral SCC cells
A computational method for designing diverse linear epitopes including citrullinated peptides with desired binding affinities to intravenous immunoglobulin
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