861 resultados para Line Drop Compensator


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Signaling through the Notch1 receptor is essential for the control of numerous developmental processes during embryonic life as well as in adult tissue homeostasis and disease. Since the outcome of Notch1 signaling is highly context-dependent, and its precise physiological and pathological role in many organs is unclear, it is of great interest to localize and identify the cells that receive active Notch1 signals in vivo. Here, we report the generation and characterization of a BAC-transgenic mouse line, N1-Gal4VP16, that when crossed to a Gal4-responsive reporter mouse line allowed the identification of cells undergoing active Notch1 signaling in vivo. Analysis of embryonic and adult N1-Gal4VP16 mice demonstrated that the activation pattern of the transgene coincides with previously observed activation patterns of the endogenous Notch1 receptor. Thus, this novel reporter mouse line provides a unique tool to specifically investigate the spatial and temporal aspects of Notch1 signaling in vivo. genesis 50:700-710, 2012. © 2012 Wiley Periodicals, Inc.

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An instrument designed to measure thermal conductivity of consolidated rocks, dry or saturated, using a transient method is presented. The instrument measures relative values of the thermal conductivity, and it needs calibration to obtain absolute values. The device can be used as heat pulse line source and as continuous heat line source. Two parameters to determine thermal conductivity are proposed: TMAX, in heat pulse line source, and SLOPE, in continuous heat line source. Its performance is better, and the operation simpler, in heat pulse line-source mode with a measuring time of 170 s and a reproducibility better than 2.5%. The sample preparation is very simple on both modes. The performance has been tested with a set of ten rocks with thermal conductivity values between 1.4 and 5.2 W m¿1 K¿1 which covers the usual range for consolidated rocks.

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BACKGROUND: Poor tolerance and adverse drug reactions are main reasons for discontinuation of antiretroviral therapy (ART). Identifying predictors of ART discontinuation is a priority in HIV care. METHODS: A genetic association study in an observational cohort to evaluate the association of pharmacogenetic markers with time to treatment discontinuation during the first year of ART. Analysis included 577 treatment-naive individuals initiating tenofovir (n = 500) or abacavir (n = 77), with efavirenz (n = 272), lopinavir/ritonavir (n = 184), or atazanavir/ritonavir (n = 121). Genotyping included 23 genetic markers in 15 genes associated with toxicity or pharmacokinetics of the study medication. Rates of ART discontinuation between groups with and without genetic risk markers were assessed by survival analysis using Cox regression models. RESULTS: During the first year of ART, 190 individuals (33%) stopped 1 or more drugs. For efavirenz and atazanavir, individuals with genetic risk markers experienced higher discontinuation rates than individuals without (71.15% vs 28.10%, and 62.5% vs 14.6%, respectively). The efavirenz discontinuation hazard ratio (HR) was 3.14 (95% confidence interval (CI): 1.35-7.33, P = .008). The atazanavir discontinuation HR was 9.13 (95% CI: 3.38-24.69, P < .0001). CONCLUSIONS: Several pharmacogenetic markers identify individuals at risk for early treatment discontinuation. These markers should be considered for validation in the clinical setting.

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BACKGROUND: Sorafenib (Sb) is a multiple kinase inhibitor targeting both tumour cell proliferation and angiogenesis that may further act as a potent radiosensitizer by arresting cells in the most radiosensitive cell cycle phase. This phase I open-label, noncontrolled dose escalation study was performed to determine the safety and maximum tolerated dose (MTD) of Sb in combination with radiation therapy (RT) and temozolomide (TMZ) in 17 patients with newly diagnosed high-grade glioma. METHODS: Patients were treated with RT (60 Gy in 2 Gy fractions) combined with TMZ 75 mg m(-2) daily, and Sb administered at three dose levels (200 mg daily, 200 mg BID, and 400 mg BID) starting on day 8 of RT. Thirty days after the end of RT, patients received monthly TMZ (150-200 mg m(-2) D1-5/28) and Sb (400 mg BID). Pharmacokinetic (PK) analyses were performed on day 8 (TMZ) and on day 21 (TMZ&Sb) (Clinicaltrials ID: NCT00884416). RESULTS: The MTD of Sb was established at 200 mg BID. Dose-limiting toxicities included thrombocytopenia (two patients), diarrhoea (one patient) and hypercholesterolaemia (one patient). Sb administration did not affect the mean area under the curve(0-24) and mean Cmax of TMZ and its metabolite 5-amino-imidazole-4-carboxamide (AIC). Tmax of both TMZ and AIC was delayed from 0.75 (TMZ alone) to 1.5 h (combined TMZ/Sb). The median progression-free survival was 7.9 months (95% confidence interval (CI): 5.4-14.55), and the median overall survival was 17.8 months (95% CI: 14.7-25.6). CONCLUSIONS: Although Sb can be combined with RT and TMZ, significant side effects and moderate outcome results do not support further clinical development in malignant gliomas. The robust PK data of the TMZ/Sb combination could be useful in other cancer settings.

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PURPOSE Updated results are presented after a median follow-up of 7.3 years from the phase III First-Line Indolent Trial of yttrium-90 ((90)Y) -ibritumomab tiuxetan in advanced-stage follicular lymphoma (FL) in first remission. PATIENTS AND METHODS Patients with CD20(+) stage III or IV FL with complete response (CR), unconfirmed CR (CRu), or partial response (PR) after first-line induction treatment were randomly assigned to (90)Y-ibritumomab consolidation therapy (rituximab 250 mg/m(2) days -7 and 0, then (90)Y-ibritumomab 14.8 MBq/kg day 0; maximum 1,184 MBq) or no further treatment (control). Primary end point was progression-free survival (PFS) from date of random assignment. Results For 409 patients available for analysis ((90)Y-ibritumomab, n = 207; control, n = 202), estimated 8-year overall PFS was 41% with (90)Y-ibritumomab versus 22% for control (hazard ratio [HR], 0.47; P < .001). For patients in CR/CRu after induction, 8-year PFS with (90)Y-ibritumomab was 48% versus 32% for control (HR, 0.61; P = .008), and for PR patients, it was 33% versus 10% (HR, 0.38; P < .001). For (90)Y-ibritumomab consolidation, median PFS was 4.1 years (v 1.1 years for control; P < .001). Median time to next treatment (TTNT) was 8.1 years for (90)Y-ibritumomab versus 3.0 years for control (P < .001) with approximately 80% response rates to second-line therapy in either arm, including autologous stem-cell transplantation. No unexpected toxicities emerged during long-term follow-up. Estimated between-group 8-year overall survival rates were similar. Annualized incidence rate of myelodysplastic syndrome/acute myeloblastic leukemia was 0.50% versus 0.07% in (90)Y-ibritumomab and control groups, respectively (P = .042). CONCLUSION (90)Y-ibritumomab consolidation after achieving PR or CR/CRu to induction confers 3-year benefit in median PFS with durable 19% PFS advantage at 8 years and improves TTNT by 5.1 years for patients with advanced FL.

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A 6N-dimensional alternative formulation is proposed for constrained Hamiltonian systems. In this context the noninteraction theorem is derived from the world-line conditions. A model of two interacting particles is exhibited where physical coordinates are canonical.

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Background: Gastrointestinal stromal tumors (GISTs) are rare mesenchymal tumors usually caused by mutations in the KIT or PDGFRA gene. Advanced disease generally cannot be cured by surgery nor by tyrosine kinase inhibitors (TKI), but TKIs have considerably improved outcome for patients (pts) with advanced GIST. Patients failing TKI treatment with imatinib (IM), sunitinib (SU) or nilotinib (NI) have a poor prognosis. Sorafenib is a multi kinase inhibitor that blocks not only receptor tyrosine kinases such as KIT, VEGFR and PDGFR but also serine/threonine kinases along the RAS/RAF/MEK/ERK pathway. Recently, clinical activity of sorafenib in third-line treatment in patients with GIST after IM and SU failure has been shown (Wiebe et al. ASCO 2008, #10502). Methods: We report herein preliminary data of 32 pts treated with sorafenib in nine European centers. Centers were selected based on their previous and known experience in GIST and reported all pts treated. Pts received sorafenib after failure of IM, SU and NI in fourth-line treatment. Baseline characteristics and treatment details have been retrieved via questionary. Results: Median age at sorafenib treatment start was 62 years (range 33-81 y), and the majority of pts were male (63 %). Primary tumor site was gastric or small intestine in 25% and 41% of pts, respectively. All pts had failed IM, SU, NI. 19 % of pts achieved partial remission and 44% disease stabilization. Approximately half of the pts had an improvement of symptoms and/or performance. Half of the pts were on treatment longer than 4 months (actuarial data) and 41% of pts continue to receive sorafenib. Median progression-free survival is 20 weeks and median overall survival 42 weeks (Kaplan-Meier), at a median follow-up of 22 weeks (range 3-54). Conclusions: This is the largest series assessing efficacy of sorafenib fourth-line treatment for IM, SU and NI refractory GIST reported yet. Sorafenib displays significant clinical activity in this heavily pretreated group of patients.

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Over the past few decades, Fourier transform infrared (FTIR) spectroscopy coupled to microscopy has been recognized as an emerging and potentially powerful tool in cancer research and diagnosis. For this purpose, histological analyses performed by pathologists are mostly carried out on biopsied tissue that undergoes the formalin-fixation and paraffin-embedding (FFPE) procedure. This processing method ensures an optimal and permanent preservation of the samples, making FFPE-archived tissue an extremely valuable source for retrospective studies. Nevertheless, as highlighted by previous studies, this fixation procedure significantly changes the principal constituents of cells, resulting in important effects on their infrared (IR) spectrum. Despite the chemical and spectral influence of FFPE processing, some studies demonstrate that FTIR imaging allows precise identification of the different cell types present in biopsied tissue, indicating that the FFPE process preserves spectral differences between distinct cell types. In this study, we investigated whether this is also the case for closely related cell lines. We analyzed spectra from 8 cancerous epithelial cell lines: 4 breast cancer cell lines and 4 melanoma cell lines. For each cell line, we harvested cells at subconfluence and divided them into two sets. We first tested the "original" capability of FTIR imaging to identify these closely related cell lines on cells just dried on BaF2 slides. We then repeated the test after submitting the cells to the FFPE procedure. Our results show that the IR spectra of FFPE processed cancerous cell lines undergo small but significant changes due to the treatment. The spectral modifications were interpreted as a potential decrease in the phospholipid content and protein denaturation, in line with the scientific literature on the topic. Nevertheless, unsupervised analyses showed that spectral proximities and distances between closely related cell lines were mostly, but not entirely, conserved after FFPE processing. Finally, PLS-DA statistical analyses highlighted that closely related cell lines are still successfully identified and efficiently distinguished by FTIR spectroscopy after FFPE treatment. This last result paves the way towards identification and characterization of cellular subtypes on FFPE tissue sections by FTIR imaging, indicating that this analysis technique could become a potential useful tool in cancer research.

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BACKGROUND: Gefitinib is active in patients with pretreated non-small-cell lung cancer (NSCLC). We evaluated the activity and toxicity of gefitinib first-line treatment in advanced NSCLC followed by chemotherapy at disease progression. PATIENTS AND METHODS: In all, 63 patients with chemotherapy-naive stage IIIB/IV NSCLC received gefitinib 250 mg/day. At disease progression, gefitinib was replaced by cisplatin 80 mg/m(2) on day 1 and gemcitabine 1250 mg/m(2) on days 1, 8 for up to six 3-week cycles. Primary end point was the disease stabilization rate (DSR) after 12 weeks of gefitinib. RESULTS: After 12 weeks of gefitinib, the DSR was 24% and the response rate (RR) was 8%. Median time to progression (TtP) was 2.5 months and median overall survival (OS) 11.5 months. Never smokers (n = 9) had a DSR of 56% and a median OS of 20.2 months; patients with epidermal growth factor receptor (EGFR) mutation (n = 4) had a DSR of 75% and the median OS was not reached after the follow-up of 21.6 months. In all, 41 patients received chemotherapy with an overall RR of 34%, DSR of 71% and median TtP of 6.7 months. CONCLUSIONS: First-line gefitinib monotherapy led to a DSR of 24% at 12 weeks in an unselected patients population. Never smokers and patients with EGFR mutations tend to have a better outcome; hence, further trials in selected patients are warranted.

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The Transportation Equity Act of the 21st Century mandated environmental streamlining in order to improve transportation project delivery without compromising environmental protection. In accordance with TEA-21, the environmental review process for this project has been documented as a Streamlined Environmental Assessment. This document addresses only those resources or features that apply to the project. This allowed study and discussion of resources present in the study area, rather than expend effort on resources that were either not present or not impacted. Although not all resources are discussed in the EA, they were considered during the planning process and are documented in the Streamlined Resource Summary.

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The mechanisms sustaining high blood pressure in conscious one-kidney, one-clip Goldblatt rats were evaluated with the use of SK&F 64139, a phenylethanolamine N-methyltransferase inhibitor capable of crossing the blood-brain barrier and of captopril, an angiotensin converting enzyme inhibitor. The rats were studied 3 weeks after left renal artery clipping and contralateral nephrectomy. During the developmental phase of hypertension, two groups of rats were maintained on a regular salt (RNa) intake, whereas two other groups were given a low salt (LNa) diet. On the day of the experiment, the base-line mean blood pressure measured in the LNa rats (177.4 +/- 5.2 mm Hg, mean +/- S.E., n = 15) was similar to that measured in the RNa rats (178.7 +/- 5.4 mm Hg, n = 16). SK&F 64139 (12.5 mg p.o.) induced a significantly more pronounced (P less than .001) blood pressure decrease in the RNa rats (-25.6 +/- 3.6 mm Hg, n = 8) than in the LNa rats (-4.3 +/- 3.3 mm Hg, n = 7) during a 90-min observation period. On the other hand, captopril (10 mg p.o.) normalized blood pressure in LNa rats (n = 8), but produced only a 13.4 mm Hg blood pressure drop in RNa rats (n = 8). RNa rats treated with SK&F 64139 were found to have decreased phenylethanolamine N-methyltransferase activity by an average 80% in selected brain stem nuclei when compared with nontreated rats. No significant difference in plasma catecholamine levels was found between the RNa and LNa rats. These results suggest that, in this experimental model of hypertension, the sodium ion might increase the model of hypertension, the sodium ion might increase the vasoconstrictor contribution of the sympathetic system via a centrally mediated neurogenic mechanism while at the same time it decreases the renin-dependency of the high blood pressure.

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Phosphopeptides tagging reactions by dinuclear zinc(II) complexes (1,3-bis[bis(2-pyridylmethyl)amino]-propan-2-olato dizinc(II)3+, called tag) were performed with a dual-channel microsprayer in electrospray ionization mass spectrometry. The reaction is first studied ex situ and analyzed with a commercial electrospray source. In situ reactions (i.e., inside the Taylor cone) were achieved with a dual-channel microsprayer both with the tag synthesized chemically before the experiments and with the tag electrogenerated by in situ oxidation of a zinc electrode, also used to apply the electrospray current. The device consists of a polyimide microchip with two microchannels (20 microm x 50 microm x 1 cm) etched on each side of the structure and connecting only at the tip of the microchip. We demonstrate here that mixing two solutions with different physicochemical properties inside the Taylor cone can be used to selectively tag target molecules.

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Point defects of opposite signs can alternately nucleate on the -1/2 disclination line that forms near the free surface of a confined nematic liquid crystal. We show the existence of metastable configurations consisting of periodic repetitions of such defects. These configurations are characterized by a minimal interdefect spacing that is seen to depend on sample thickness and on an applied electric field. The time evolution of the defect distribution suggests that the defects attract at small distances and repel at large distances.

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The objective of this analysis was to assess the radiation exposure associated with (90)Y-ibritumomab tiuxetan when used as consolidation therapy in adults with low or minimal tumor burden after first-line therapy of advanced follicular lymphoma (FL). METHODS: The patients who were enrolled in the phase 3 first-line indolent trial were 18 y or older, with CD20(+) grade 1 or 2 stage III or IV FL, and a partial response, complete response, or unconfirmed complete response to first-line chemotherapy. The patients were allocated randomly to receive a single infusion of unlabeled rituximab 250 mg/m(2) on day -7 and consolidation on day 0 with a single dose of (90)Y-ibritumomab tiuxetan, 14.8 MBq/kg, immediately after unlabeled rituximab, 250 mg/m(2), or no further treatment. On day -7, a subset of patients received an injection of 185 MBq of (111)In-ibritumomab tiuxetan immediately after unlabeled rituximab, 250 mg/m(2), for central dosimetry analysis. Correlations were assessed between organ radiation absorbed dose and toxicity, body weight, body mass index, and progression-free survival. RESULTS: Central dosimetry evaluations were available from 57 of 70 patients. Median radiation absorbed doses were 100 cGy (range, 28-327 cGy) for the red marrow and 72 cGy (range, 46-106 cGy) for the whole body. Radiation absorbed doses did not differ significantly between patients who had a partial response or complete response to initial therapy. Progression-free survival correlated significantly with the whole-body (r = 0.4401; P = 0.0006) and bone marrow (r = 0.2976; P = 0.0246) radiation dose. Body weight was significantly negatively correlated with whole-body radiation dose (r = -0.4971; P < 0.0001). Neither the whole-body radiation dose nor the bone marrow radiation dose correlated with hematologic toxicity. CONCLUSION: In patients with low or minimal residual tumor burden after first-line chemotherapy of advanced FL, whole-body and bone marrow exposure after (90)Y-ibritumomab tiuxetan consolidation showed a significant positive correlation with progression-free survival, whereas dosimetric data could not predict hematologic toxicity.

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Glucagon-like peptide-1(7-36)amide (tGLP-1), oxyntomodulin (OXM), and glucagon are posttranslational end products of the glucagon gene expressed in intestinal L-cells. In vivo, these peptides are potent inhibitors of gastric acid secretion via several pathways, including stimulation of somatostatin release. We have examined the receptors through which these peptides stimulate somatostatin secretion using the somatostatin-secreting cell line RIN T3. tGLP-1, OXM, and glucagon stimulated somatostatin release and cAMP accumulation in RIN T3 cells to similar maximum levels, with ED50 values close to 0.2, 2, and 50 nM and 0.02, 0.3, and 8 nM, respectively. Binding of [125I]tGLP-1, [125I]OXM, and [125I]glucagon to RIN T3 plasma membranes was inhibited by the three peptides, with relative potencies as follows: tGLP-1 &gt; OXM &gt; glucagon. Whatever the tracer used, the IC50 for tGLP-1 was close to 0.15 nM and was shifted rightward for OXM and glucagon by about 1 and 2-3 orders of magnitude, respectively. Scatchard analyses for the three peptides were compatible with a single class of receptor sites displaying a similar maximal binding close to 2 pmol/mg protein. In the hamster lung fibroblast cell line CCL39 transfected with the receptor for tGLP-1, binding of [125I]tGLP-1 was inhibited by tGLP-1, OXM, and glucagon, with relative potencies close to those obtained with RIN T3 membranes. Chemical cross-linking of [125I]tGLP-1, [125I]OXM, and [125I]glucagon revealed a single band at 63,000 mol wt, the intensity of which was dose-dependently reduced by all three peptides. These data suggest that in the somatostatin-secreting cell line RIN T3, OXM and glucagon stimulate somatostatin release through a tGLP-1-preferring receptor. This suggests that some biological effects, previously described for these peptides, might be due to their interaction with this receptor.