201 resultados para PHASE PHOTOCATALYZED REACTIONS
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E2F transcriptional regulators control human-cell proliferation by repressing and activating the transcription of genes required for cell-cycle progression, particularly the S phase. E2F proteins repress transcription in association with retinoblastoma pocket proteins, but less is known about how they activate transcription. Here, we show that the human G1 phase regulator HCF-1 associates with both activator (E2F1 and E2F3a) and repressor (E2F4) E2F proteins, properties that are conserved in insect cells. Human HCF-1-E2F interactions are versatile: their associations and binding to E2F-responsive promoters are cell-cycle selective, and HCF-1 displays coactivator properties when bound to the E2F1 activator and corepressor properties when bound to the E2F4 repressor. During the G1-to-S phase transition, HCF-1 recruits the mixed-lineage leukemia (MLL) and Set-1 histone H3 lysine 4 methyltransferases to E2F-responsive promoters and induces histone methylation and transcriptional activation. These results suggest that HCF-1 induces cell-cycle-specific transcriptional activation by E2F proteins to promote cell proliferation.
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Background: The prevalence of small intestinal bowel bacterial overgrowth (SIBO) in patients with irritable bowel syndrome (IBS) ranges from 43% to 78% as determined by the lactulose hydrogen breath (LHBT) test. Although rifaximine, a non-absorbable antibiotic, has been able to decrease global IBS symptoms as well as bloating in placebo-controlled randomized trials, these results were not repeated in phase IV studies in daily clinical practice. Aim: To assess the prevalence of SIBO in an IBS cohort and to evaluate the treatment response in the IBS cohort affected by SIBO. Methods: Enrolled patients were diagnosed with IBS using the following criteria: fulfillment of the Rome III criteria, absence of alarm symptoms (anemia, weight loss, nocturnal symptoms etc), normal fecal calproectin, normal endoscopic workup including histology. Celiac disease was excluded by serology and/or duodenal biopsy. All patients underwent lactulose hydrogen breath testing (LHBT) for SIBO diagnosis. Patients with SIBO were treated with rifaximine tablets (400mg twice daily for 14 days). Both before and at week 6 after rifaximin treatment, patients completed a questionnaire, where the following criteria were assessed individually using 11-point Likert scales: the bloating, flatulence, abdominal pain, diarrhea, and overall well-being. Results: Hundred-fifty IBS patients were enrolled (76% female, mean age 44 ± 16 years), of whom 106 (71%) were diagnosed with SIBO and consequently treated with rifaximine. Rifaximine treatment significantly reduced the following symptoms as assessed by the symptom questionnaire: bloating (5.5 ± 2.6 before vs. 3.6 ± 2.7 after treatment, p <0.001), flatulence (5 ± 2.7 vs. 4 ± 2.7, p = 0.015), diarrhea (2.9 ± 2.4 vs. 2 ± 2.4, p = 0.005), abdominal pain (4.8 ± 2.7 vs. 3.3 ± 2.5, p <0.001) and resulted in improved overall well-being (3.9 ± 2.4 vs. 2.7 ± 2.3, p <0.001). Thirteen of the 106 treated patients were lost to follow-up (12%). The LHBT was repeated 2-4 weeks after rifaximine treatment in 65/93 (70%) patients. Eradication of SIBO was documented in 85% of all patients (55/65), whereas 15% of patients (10/65) tested positive for SIBO as determined by the LHBT testing. Conclusions: The results of our phase IV trial indicate that a high proportion of IBS patients tested positive for SIBO. IBS symptoms (bloating, flatulence, diarrhea, pain, overall well-being) were significantly diminished following a 2-week treatment with rifaximine. These results support the previous findings of randomized controlled trials that the presence of SIBO is associated with symptom generation in IBS patients and that reduction and/or elimination of SIBO may help to alleviate IBSassociated symptoms.
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L'objectif de l'étude présentée est d'adapter et de valider une version française de la Stigma Scale (King, 2007) auprès d'une population de personnes souffrant de troubles psychiques. Dans une première phase, la stabilité temporelle (fidélité test-retest), la cohérence interne et la validité convergente de l'instrument original à 28 items traduit en français ont été évaluées auprès d'un échantillon de 183 patients. Les résultats d'analyses factorielles confirmatoires ne nous ont pas permis de confirmer la structure originale de l'instrument. Nous avons donc proposé, sur la base des résultats d'une analyse factorielle exploratoire, une version courte de l'échelle de stigmatisation (9 items) qui conserve la structure en trois facteurs du modèle original. Dans une deuxième phase, nous avons examiné les qualités psychométriques et validé cette version abrégée de l'échelle de stigmatisation auprès d'un second échantillon de 234 patients. Les indices d'ajustements de notre analyse factorielle confirmatoire confirme la structure en trois facteurs de la version abrégée de la Stigma Scale. Les résultats suggèrent que la version française abrégée de l'échelle de stigmatisation constitue un instrument utile, fiable et valide dans l'autoévaluation de la stigmatisation perçue par des personnes souffrant de troubles psychiques. - Aim People suffering from mental illness are exposed to stigma. However, only few tools are available to assess stigmatization as perceived from the patient's perspective. The aim of this study is to adapt and validate a French version of the Stigma Scale (King, 2007). This self-report questionnaire has a three-factor structure: discrimination, disclosure and positive aspects of mental illness. Discrimination subscale refers to perceived negative reactions by others. Disclosure subscale refers mainly to managing disclosure to avoid discrimination and finally positive aspects subscale taps into how patients are becoming more accepting, more understanding toward their illness. Method In the first step, internal consistency, convergent validity and test-retest reliability of the French adaptation of the 28-item scale have been assessed on a sample of 183 patients. Results of confirmatory factor analyses (CFA) did not confirm the hypothesized structure. In light of the failed attempts to validate the original version, an alternative 9-item short-form version of the Stigma Scale, maintaining the integrity of the original model, was developed based on results of exploratory factor analyses in the first sample and cross- validated in a new sample of 234 patients. Results Results of CFA did not confirm that the data fitted well to the three-factor model of the 28-item Stigma Scale (χ2/άί=2.02, GFI=0.77, AGFI=0.73, RMSEA=0.07, CFI=0.77 et NNFI=0.75). Cronbach's α are excellent for discrimination (0.84) and disclosure (0.83) subscales but poor for potential positive aspects (0.46). External validity is satisfactory. Overall Stigma Scale total score is negatively correlated with score on Rosenberg's Self-Esteem Scale (r = -0.49), and each sub-scale is significantly correlated with a visual analogue scale that refers to the specific aspect of stigma (0.43 < |r| < 0.60). Intraclass correlation coefficients between 0.68 and 0.89 indicate good test- retest reliability. Results of CFA demonstrate that the items chosen for the short version of the Stigma Scale have the expected fit properties fa2/df=1.02, GFI=0.98, AGFI=0.98, RMSEA=0.01, CFI=1.0 et NNFI=1.0). Considering the small number (3 items) of items in each subscales of the short version of the Stigma Scale, a coefficients for the discrimination (0.57), disclosure (0.80) and potential positive aspects subscales (0.62) are considered as good. Conclusion Our results suggest that the 9-item French short-version of the Stigma Scale is a useful, reliable and valid self-report questionnaire to assess perceived stigmatization in people suffering from mental illness. The time of completion is really short and questions are well understood and accepted by the patients.
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Extranodal NK/T-cell lymphoma, nasal type, is a rare and highly aggressive disease with a grim prognosis. No therapeutic strategy is currently identified in relapsing patients. We report the results of a French prospective phase II trial of an L-asparaginase-containing regimen in 19 patients with relapsed or refractory disease treated in 13 centers. Eleven patients were in relapse and 8 patients were refractory to their first line of treatment. L-Asparaginase-based treatment yielded objective responses in 14 of the 18 evaluable patients after 3 cycles. Eleven patients entered complete remission (61%), and only 4 of them relapsed. The median overall survival time was 1 year, with a median response duration of 12 months. The main adverse events were hepatitis, cytopenia, and allergy. The absence of antiasparaginase antibodies and the disappearance of Epstein-Barr virus serum DNA were significantly associated with a better outcome. These data confirm the excellent activity of L-asparaginase-containing regimens in extranodal NK/T-cell lymphoma. L-Asparaginase-based treatment should thus be considered for salvage therapy, especially in patients with disseminated disease. First-line L-asparaginase combination therapy for extranodal NK/T-cell lymphoma warrants evaluation in prospective trials. This trial is registered at www.clinicaltrials.gov as #NCT00283985.
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Different interferometric techniques were developed last decade to obtain full field, quantitative, and absolute phase imaging, such as phase-shifting, Fourier phase microscopy, Hilbert phase microscopy or digital holographic microscopy (DHM). Although, these techniques are very similar, DHM combines several advantages. In contrast, to phase shifting, DHM is indeed capable of single-shot hologram recording allowing a real-time absolute phase imaging. On the other hand, unlike to Fourier phase or Hilbert phase microscopy, DHM does not require to record in focus images of the specimen on the digital detector (CCD or CMOS camera), because a numerical focalization adjustment can be performed by a numerical wavefront propagation. Consequently, the depth of view of high NA microscope objectives is numerically extended. For example, two different biological cells, floating at different depths in a liquid, can be focalized numerically from the same digital hologram. Moreover, the numerical propagation associated to digital optics and automatic fitting procedures, permits vibrations insensitive full- field phase imaging and the complete compensation for a priori any image distortion or/and phase aberrations introduced for example by imperfections of holders or perfusion chamber. Examples of real-time full-field phase images of biological cells have been demonstrated. ©2008 COPYRIGHT SPIE
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Vaginal delivery can cause lesions of the various pelvic structures responsible for the mechanisms of continence. These lesions may perhaps be prevented in the future by measuring pressure generated during childbirth. Tear of the anal sphincter during childbirth is a marker of a global impairment of the urinary, ano-rectal and sexual pelvic functions in the short and medium term. Persistence of a defect of the anal sphincter is frequent in spite of immediate suture. The correlation between these defects and ano-rectal incontinence are not established in our experience. The quality of the contraction of the sphincter complex and pubo-rectal sling seems to play a more important role in ano-rectal continence after a traumatic childbirth.
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The application of two approaches for high-throughput, high-resolution X-ray phase contrast tomographic imaging being used at the tomographic microscopy and coherent radiology experiments (TOMCAT) beamline of the SLS is discussed and illustrated. Differential phase contrast (DPC) imaging, using a grating interferometer and a phase-stepping technique, is integrated into the beamline environment at TOMCAT in terms of the fast acquisition and reconstruction of data and the availability to scan samples within an aqueous environment. A second phase contrast method is a modified transfer of intensity approach that can yield the 3D distribution of the decrement of the refractive index of a weakly absorbing object from a single tomographic dataset. The two methods are complementary to one another: the DPC method is characterised by a higher sensitivity and by moderate resolution with larger samples; the modified transfer of intensity approach is particularly suited for small specimens when high resolution (around 1 mu m) is required. Both are being applied to investigations in the biological and materials science fields.
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The treatment of some cancer patients has shifted from traditional, non-specific cytotoxic chemotherapy to chronic treatment with molecular targeted therapies. Imatinib mesylate, a selective inhibitor of tyrosine kinases (TKIs) is the most prominent example of this new era and has opened the way to the development of several additional TKIs, including sunitinib, nilotinib, dasatinib, sorafenib and lapatinib, in the treatment of various hematological malignancies and solid tumors. All these agents are characterized by an important inter-individual pharmacokinetic variability, are at risk for drug interactions, and are not devoid of toxicity. Additionally, they are administered for prolonged periods, anticipating the careful monitoring of their plasma exposure via Therapeutic Drug Monitoring (TDM) to be an important component of patients' follow-up. We have developed a liquid chromatography-tandem mass spectrometry method (LC-MS/MS) requiring 100 microL of plasma for the simultaneous determination of the six major TKIs currently in use. Plasma is purified by protein precipitation and the supernatant is diluted in ammonium formate 20 mM (pH 4.0) 1:2. Reverse-phase chromatographic separation of TKIs is obtained using a gradient elution of 20 mM ammonium formate pH 2.2 and acetonitrile containing 1% formic acid, followed by rinsing and re-equilibration to the initial solvent composition up to 20 min. Analyte quantification, using matrix-matched calibration samples, is performed by electro-spray ionization-triple quadrupole mass spectrometry by selected reaction monitoring detection using the positive mode. The method was validated according to FDA recommendations, including assessment of extraction yield, matrix effects variability (<9.6%), overall process efficiency (87.1-104.2%), as well as TKIs short- and long-term stability in plasma. The method is precise (inter-day CV%: 1.3-9.4%), accurate (-9.2 to +9.9%) and sensitive (lower limits of quantification comprised between 1 and 10 ng/mL). This is the first broad-range LC-MS/MS assay covering the major currently in-use TKIs. It is an improvement over previous methods in terms of convenience (a single extraction procedure for six major TKIs, reducing significantly the analytical time), sensitivity, selectivity and throughput. It may contribute to filling the current knowledge gaps in the pharmacokinetics/pharmacodynamics relationships of the latest TKIs developed after imatinib and better define their therapeutic ranges in different patient populations in order to evaluate whether a systematic TDM-guided dose adjustment of these anticancer drugs could contribute to minimize the risk of major adverse reactions and to increase the probability of efficient, long lasting, therapeutic response.
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The current study conceptualized observer reactions to uncivil behavior towards women as an ethical behavior and examined three factors (target reaction, actor motive, and actor-target relationship) that influence these reactions. Two vignette studies with women and men undergraduate and graduate students in western Switzerland were conducted. Study 1 (N=148) was a written vignette study that assessed how the reaction of female targets to incivility and the motives of actors influenced observer reactions. Results showed that a female target's reaction influenced observers' evaluations of the harm caused by an uncivil incident, and that an actor's motive affected observers' assessments of the necessity to intervene. Study 2 (N=81) was a video vignette study that assessed the effects of the reactions by female targets to incivility and the relationship between the target and the actor on observer reactions.We found that female targets' reactions influenced observers' evaluations of harm and the perceived necessity to intervene. Furthermore, the effect of a female target's reaction on observers' evaluations of harm was moderated by the relationship between the actor and the target: a female target who laughed at the uncivil behavior was perceived as less harmed, when she and the actor had a personal relationship than when they had a professional relationship. When the female target reacted hurt or neutrally, actor-target relationship did not affect observers' evaluations of harm. We conclude by discussing the implications of our findings for theory and practice.
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PURPOSE: to evaluate the efficacy and the safety of low dose intraocular tissue plasminogen activator (rt-PA) in the treatment of traumatic hyphema and postoperative fibrinous membrane. METHODS: Six microg to 10 microg of rt-PA was injected into the anterior chamber to treat severe fibrinous postoperative membranes and total traumatic hyphemae. RESULTS: Thirteen eyes of 13 patients were treated. Four cases of traumatic hyphema and 9 cases of fibrinous membranes were included. Complete fibrinolysis within 24 hours was observed in 4 cases (30.8%). A partial success was noted in 7 eyes (53.8%). No beneficial effect was observed in two cases of traumatic hyphema associated with intravitreal hemorrhage after penetrating trauma. No side effect attributable to rt-PA occurred. CONCLUSION: Low dose intraocular rt-PA appears to be safe and effective in the treatment of postoperative fibrinous membrane and endocular hemorrhage limited to the anterior chamber.
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BACKGROUND: Glioblastoma, the most common adult primary malignant brain tumor, confers poor prognosis (median survival of 15 months) notwithstanding aggressive treatment. Combination chemotherapy including carmustine (BCNU) or temozolomide (TMZ) with the MGMT inhibitor O6-benzylguanine (O6BG) has been used, but has been associated with dose-limiting hematopoietic toxicity. OBJECTIVE: To assess safety and efficacy of a retroviral vector encoding the O6BG-resistant MGMTP140K gene for transduction and autologous transplantation of hematopoietic stem cells (HSCs) in MGMT unmethylated, newly diagnosed glioblastoma patients in an attempt to chemoprotect bone marrowduring combination O6BG/TMZ therapy. METHODS: Three patients have been enrolled in the first cohort. Patients underwent standard radiation therapy without TMZ followed by G-CSF mobilization, apheresis, and conditioning with 600 mg/m2 BCNU prior to infusion of gene-modified cells. Posttransplant, patients were treated with 28-day cycles of single doseTMZ (472 mg/m2) with 48-hour intravenous O6BG (120 mg/m2 bolus, then 30 mg/m2/d). RESULTS: The BCNU dose was nonmyeloablative with ANC ,500/mL for ≤3 d and nadir thrombocytopenia of 28,000/mL. Gene marking in pre-infusion colony forming units (CFUs) was 70.6%, 79.0%, and 74.0% in Patients 1, 2, and 3, respectively, by CFU-PCR. Following engraftment, gene marking in white blood cells and sorted granulocytes ranged between 0.37-0.84 and 0.33-0.83 provirus copies, respectively, by real-time PCR. Posttransplant gene marking in CFUs from CD34-selected cells ranged from 28.5% to 47.4%. Patients have received 4, 3, and 2 cycles of O6BG/TMZ, respectively, with evidence for selection of gene-modified cells. One patient has received a single dose-escalated cycle at 590 mg/m2 TMZ. No additional extra-hematopoietic toxicity has been observed thus far and all three patients exhibit stable disease at 7-8 months since diagnosis CONCLUSIONS: We believe that these data demonstrate the feasibility of achieving significant engraftment of MGMTP140K-modified cells with a well-tolerated dose of BCNU. Further follow-up will determine whether this approach will allow for further dose escalation of TMZ and improved survival.
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BACKGROUND: Gemcitabine, oxaliplatin and 5-fluorouracil (5-FU) are active in biliary tract cancer and have a potentially synergistic mode of action and non-overlapping toxicity. The objective of these trials was to determine response, survival and toxicity separately in patients with bile duct cancer (BDC) and gallbladder cancer (GBC) treated with gemcitabine/oxaliplatin/5-FU chemotherapy. METHODS: Eligible patients with histologically proven, advanced or metastatic BDC (n=37) or GBC (n=35) were treated with gemcitabine (900 mg m(-2) over 30 min), oxaliplatin (65 mg m(-2)) and 5-FU (1500 mg m(-2) over 24 h) on days 1 and 8 of a 21-day cycle. Tumour response was the primary outcome measure. RESULTS: Response rates were 19% (95% CI: 6-32%) and 23% (95% CI: 9-37%) for BDC and GBC, respectively. Median survivals were 10.0 months (95% CI: 8.6-12.4) and 9.9 months (95% CI: 7.5-12.2) for BDC and GBC, respectively, and 1- and 2-year survival rates were 40 and 23% in BDC and 34 and 6% in GBC (intention-to-treat analysis). Major grade III and IV adverse events were neutropenia, thrombocytopenia, elevated bilirubin and anorexia. CONCLUSION: Triple-drug chemotherapy achieves comparable results for response and survival to previously reported regimens, but with more toxicity.