250 resultados para single scattering


Relevância:

20.00% 20.00%

Publicador:

Resumo:

The properties of CD8 T-cells requiredfor protection from infectiousdisease and cancer are only partiallycharacterized, and only limited data isavailable regarding T-cell clonotypes.It has been proposed that dominantT-cell clonotypes may have higherprotective potential than their nondominantcounterparts. Our objectiveswere to assess memory andeffector functions, stage of differentiationand clonotype selection of tumor-reactive T lymphocytes followingpeptide vaccination in melanomapatients.We also characterized dominantversus non-dominant clonotypesto further understand the in vivo functionof these T-cells based on theirprevalence. Using a novel single-cellapproach for simultaneous ex vivomolecular and functional analysis, wereport the preferential selection andexpansion of several tumor-specificco-dominant clonotypes of intermediateto high frequencies, irrespectiveof whether native or analog peptidewas used for vaccination. Theseclonotypes made up 40 - 95% of thedifferentiated "effector-like" T-cells,but only 25% of the less-differentiated"effector-memory" cells. Bothsubsets also contained non-dominantT-cell clonotypes, but these were significantlymore frequent in the lessdifferentiatedcells. Thus, cell differentiationwas clonotype-dependent.Surprisingly however, the acquisitionof memory and effector T-cell propertieswas clonotype independent, as wefound similar functional profiles indominant and low/ non-dominantT-cell clonotypes. In contrast to analogpeptide vaccination, native peptidevaccination induced T-cell functionsthat were more comprehensive,with more pronounced effector functionscombined with memory cellproperties. In summary, this study revealsthat T-cell functions are determinedprimarily by the antigen andthe stage of T-cell differentiation, butare similar in dominant and non-dominantclonotypes participating in aCD8 T-cell response. The identifiedclonotypic basis of T-cell responsescontributes to the rational developmentof vaccines.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

BACKGROUND: Data suggest that esomeprazole decreases gastric secretion. AIMS: To assess the effect of a single i.v. esomeprazole dose on gastric secretion volume 3 h after drug administration, as a primary endpoint, and to evaluate, as secondary endpoints, the reduction 1 and 5 h after dosing; time when the gastric pH was <2.5 and esomeprazole's safety. METHODS: In all, 23 healthy Helicobacter pylori-negative volunteers (10 men, 13 women, mean age 28.2 +/- 6) participated in this single-centre, randomized, double-blind, placebo-controlled, 2-way, single-dose cross-over study. In different sessions, volunteers received i.v. either esomeprazole 40 mg or placebo. An inserted double-lumen nasogastric tube perfused and aspirated gastric liquid. Mechanical fractioned aspiration measured secretion volume; aliquot spectrophotometry assessed gastric secretion volume lost to the duodenum. RESULTS: Three hours post-i.v. esomeprazole, average gastric secretion decreased by 77.6% (vs. baseline) compared to placebo. Values 1 and 5 h after dosing were 73.5% and 74.5%. Five hours after esomeprazole, the gastric pH was <2.5 3.9% of the time and 73.3% after placebo (P < 0.002). Esomeprazole was well-tolerated. No serious adverse events occurred. CONCLUSIONS: Intravenous esomeprazole decreases gastric secretions. The potential clinical impact in averting bronchoaspiration during anaesthesia induction and in intensive care patients should be investigated in further studies.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

BACKGROUND: HIV-infected individuals have an increased risk of myocardial infarction. Antiretroviral therapy (ART) is regarded as a major determinant of dyslipidemia in HIV-infected individuals. Previous genetic studies have been limited by the validity of the single-nucleotide polymorphisms (SNPs) interrogated and by cross-sectional design. Recent genome-wide association studies have reliably associated common SNPs to dyslipidemia in the general population. METHODS AND RESULTS: We validated the contribution of 42 SNPs (33 identified in genome-wide association studies and 9 previously reported SNPs not included in genome-wide association study chips) and of longitudinally measured key nongenetic variables (ART, underlying conditions, sex, age, ethnicity, and HIV disease parameters) to dyslipidemia in 745 HIV-infected study participants (n=34 565 lipid measurements; median follow-up, 7.6 years). The relative impact of SNPs and ART to lipid variation in the study population and their cumulative influence on sustained dyslipidemia at the level of the individual were calculated. SNPs were associated with lipid changes consistent with genome-wide association study estimates. SNPs explained up to 7.6% (non-high-density lipoprotein cholesterol), 6.2% (high-density lipoprotein cholesterol), and 6.8% (triglycerides) of lipid variation; ART explained 3.9% (non-high-density lipoprotein cholesterol), 1.5% (high-density lipoprotein cholesterol), and 6.2% (triglycerides). An individual with the most dyslipidemic antiretroviral and genetic background had an approximately 3- to 5-fold increased risk of sustained dyslipidemia compared with an individual with the least dyslipidemic therapy and genetic background. CONCLUSIONS: In the HIV-infected population treated with ART, the weight of the contribution of common SNPs and ART to dyslipidemia was similar. When selecting an ART regimen, genetic information should be considered in addition to the dyslipidemic effects of ART agents.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objective: To demonstrate successful in situ aortoiliac reconstruction of an infected infrarenal aneurysm using one single superficial femoral vein (SFV). Methods: In situ reconstruction using the right SFV sutured in end-to-end anastomosis with the aorta and distally with the right common iliac artery and in end-to-side anastomosis with the left common iliac artery. Results: The operating time was less than reported for aortic in situ reconstruction with bilateral SFV harvesting. The duplex scan 3 months postoperatively showed permeability of the bypass without any anastomotic stenosis or pseudoaneurysm. The right common femoral, popliteal, and greater saphenous veins were patent without thrombus, and the patient did not complain about peripheral edema. Conclusions: The use of only one instead of both the SFVs for aortobiiliac in situ reconstruction might be a way to reduce operating time and allow autogenous venous reconstruction even in patients with limited availability of venous material.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Single-trial analysis of human electroencephalography (EEG) has been recently proposed for better understanding the contribution of individual subjects to a group-analysis effect as well as for investigating single-subject mechanisms. Independent Component Analysis (ICA) has been repeatedly applied to concatenated single-trial responses and at a single-subject level in order to extract those components that resemble activities of interest. More recently we have proposed a single-trial method based on topographic maps that determines which voltage configurations are reliably observed at the event-related potential (ERP) level taking advantage of repetitions across trials. Here, we investigated the correspondence between the maps obtained by ICA versus the topographies that we obtained by the single-trial clustering algorithm that best explained the variance of the ERP. To do this, we used exemplar data provided from the EEGLAB website that are based on a dataset from a visual target detection task. We show there to be robust correspondence both at the level of the activation time courses and at the level of voltage configurations of a subset of relevant maps. We additionally show the estimated inverse solution (based on low-resolution electromagnetic tomography) of two corresponding maps occurring at approximately 300 ms post-stimulus onset, as estimated by the two aforementioned approaches. The spatial distribution of the estimated sources significantly correlated and had in common a right parietal activation within Brodmann's Area (BA) 40. Despite their differences in terms of theoretical bases, the consistency between the results of these two approaches shows that their underlying assumptions are indeed compatible.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Primary systemic amyloidosis (AL amyloidosis) continues to have a very poor prognosis. Most therapeutic strategies remain unsatisfactory. Conventional chemotherapy is known to offer at best only moderate efficacy. Several studies have yielded higher complete response rates after high-dose chemotherapy and autologous stem cell transplantation (ASCT) in addition to improving outcomes in a subgroup of patients. However, the superiority of an intensive approach in AL amyloidosis has not been confirmed in a randomised trial. The precise role of ASCT remains unclear. We report our experience in 16 patients diagnosed with AL amyloidosis and treated in a multidisciplinary approach with high-dose melphalan and ASCT. Median age was 59 (39-71) years. The kidneys were predominantly affected in 75% of cases; two or more organs were affected in 38%. Median time from diagnosis to transplantation was 2 (1-4) months. Three patients (19%) developed acute renal failure and required transient dialysis. Transplant-related mortality was 6% after 100 days. Haematological complete response (CR) was obtained in nine (56%) and organ response in six (38%) patients. Nine out of 12 patients (75%) with kidney involvement exhibited a sustained clinical benefit at 12 months. Half of all the patients (n = 8) were alive after a median follow-up of 33 months, including two in continuous CR. This suggests that high-dose chemotherapy and ASCT are still valid treatment options in AL amyloidosis and that a significant number of patients with renal involvement might benefit from this approach.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The Brianconnais area is explained as a large scale exotic terrain separating from Europe during the opening of the Valais ocean. It's displacement history during the Alpine evolution allows to replace older concepts of multiple oceans separating narrow strips of continental crust.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This tutorial review details some of the recent advances in signal analyses applied to event-related potential (ERP) data. These "electrical neuroimaging" analyses provide reference-independent measurements of response strength and response topography that circumvent statistical and interpretational caveats of canonical ERP analysis methods while also taking advantage of the greater information provided by high-density electrode montages. Electrical neuroimaging can be applied across scales ranging from group-averaged ERPs to single-subject and single-trial datasets. We illustrate these methods with a tutorial dataset and place particular emphasis on their suitability for studies of clinical and/or developmental populations.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Substance P (SP), an undecapeptide belonging to the tachykinin family, is released during the activation of sensory nerves, and causes vasodilation, edema and pain through activation of tissular Neurokinin 1 receptors. SP proinflammatory effects are terminated by angiotensin converting enzyme (ACE) and neutral endopeptidase (NEP), while the aminopeptidase dipeptidylpeptidase IV (DPPIV) can also play a role. The aim of this randomized, crossover, double-blind study was to assess the cutaneous vasoreactivity (flare and wheal reaction, burning pain sensation) to intradermal injection of ascending doses of SP in six volunteers receiving a single therapeutic dose of the DPPIV inhibitor sitagliptin or a matching placebo. Cutaneous SP challenges produced the expected, dose-dependent flare and wheal response, while eliciting mild to moderate local pain sensation with little dose dependency. However, no differences were shown in the responses observed under sitagliptin compared with placebo, while the study would have been sufficiently powered to detect a clinically relevant increase in sensitivity to SP. The results of this pilot study are in line with proteolytic cleavage of SP by ACE and NEP compensating the blockade of DPPIV to prevent an augmentation of its proinflammatory action.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The capabilities of a high-resolution (HR), accurate mass spectrometer (Exactive-MS) operating in full scan MS mode was investigated for the quantitative LC/MS analysis of drugs in patients' plasma samples. A mass resolution of 50,000 (FWHM) at m/z 200 and a mass extracted window of 5 ppm around the theoretical m/z of each analyte were used to construct chromatograms for quantitation. The quantitative performance of the Exactive-MS was compared with that of a triple quadrupole mass spectrometer (TQ-MS), TSQ Quantum Discovery or Quantum Ultra, operating in the conventional selected reaction monitoring (SRM) mode. The study consisted of 17 therapeutic drugs including 8 antifungal agents (anidulafungin, caspofungin, fluconazole, itraconazole, hydroxyitraconazole posaconazole, voriconazole and voriconazole-N-oxide), 4 immunosuppressants (ciclosporine, everolimus, sirolimus and tacrolimus) and 5 protein kinase inhibitors (dasatinib, imatinib, nilotinib, sorafenib and sunitinib). The quantitative results obtained with HR-MS acquisition show comparable detection specificity, assay precision, accuracy, linearity and sensitivity to SRM acquisition. Importantly, HR-MS offers several benefits over TQ-MS technology: absence of SRM optimization, time saving when changing the analysis from one MS to another, more complete information of what is in the samples and easier troubleshooting. Our work demonstrates that U/HPLC coupled to Exactive HR-MS delivers comparable results to TQ-MS in routine quantitative drug analyses. Considering the advantages of HR-MS, these results suggest that, in the near future, there should be a shift in how routine quantitative analyses of small molecules, particularly for therapeutic drugs, are performed.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Problem solving (including insight, divergent thinking) seems to rely on the right hemisphere (RH). These functions are difficult to assess behaviorally. We propose anagram resolution as a suitable paradigm. University students (n=32) performed three tachistoscopic lateralized visual half-field experiments (stimulus presentation 150ms). In Experiment 1, participants recalled four-letter strings. Subsequently, participants provided solutions for four-letter anagrams (one solution in Experiment 2; two solutions in Experiment 3). Additionally, participants completed a schizotypy questionnaire (O-LIFE). Results showed a right visual field advantage in Experiment 1 and 2, but no visual field advantage in Experiment 3. In Experiment 1, increasing positive schizotypy associated with a RH performance shift. Problem solving seems to require increasingly the RH when facing several rather than one solution. This result supports previous studies on the RH's role in remote associative, metaphor and discourse processing. The more complex language requirements, the less personality traits seem to matter.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Objectives: Osteitis pubis is a noninfectious painfulinflammatory disorder of the symphysis pubis. Etiologicfactors are numerous, the most common are: osseousextension of adductor enthesis due to sport overuse,irritation after urological and abdominal procedures, andsystemic inflammatory disorders in particular spondylarthropathies.Many cases are idiopathic. The symptomsconsist of regional chronic mechanical and sometimenocturnal pain. Diagnosis is usually confirmed by eitherbone scintigraphy or by MRI. There are no standardtreatments but conservative approaches including rest andNSAIDS are generally recommended. In 2001, a goodclinical and radiological response of three refractory caseswith 3-6 monthly perfusions of pamidronate was reported(1). Ibandronate is a much more powerful and long-lastingbisphosphonate than pamidronate, and has not yet beenreported in literature to our knowledge in this indication.Materials/Methods: We present two cases of idiopathicorigin: one woman (63 years old) and one man (36 yearsold).The symptoms were present >3 months in the firstpatient and 1 year in the second. The diagnosis wasconfirmed by MRI which showed bone edema on bothsizes of symphysis and in the second case bony erosionsadjacent to the joint were seen. Both cases failed to respondto conservative measures. Both patients received one singledirect iv Injection of 3 mg of Ibandronate.Results: The injections resulted in a rapid (within a fewdays) resolution of pain that lasted more than 6 months inboth patients. No side effects were observed. In the firstcase, an isotope bone scan performed 4 months after theinjection showed no residual uptake. The second patienthad a repeated MRI after 6 months. It demonstrated anattenuation of bone edema compared to the first MRI.Conclusions: IV Ibandronate may constitute a safe andeffective treatment option for patients with refractoryosteitis pubis.Reference: 1: Maksymowych WP, Aaron SL, Russell AS, JRheumatol 28:2754, 2001.Disclosure of Interest: None declared.