752 resultados para Neoplasms -- drug therapy
Resumo:
Mycophenolic acid, a selective inhibitor of the de novo synthesis of guanosine nucleotides in T and B lymphocytes, has been proposed to inhibit human immunodeficiency virus (HIV) replication in vitro by depleting the substrate (guanosine nucleotides) for reverse transcriptase. Here we show that mycophenolic acid induced apoptosis and cell death in a large proportion of activated CD4+ T cells, thus indicating that it may inhibit HIV infection in vitro by both virological mechanisms and immunological mechanisms (depletion of the pool of activated CD4+ T lymphocytes). Administration of mycophenolate mophetil, the ester derivate of mycophenolic acid, to HIV-infected subjects treated with anti-retroviral therapy and with undetectable viremia resulted in the reduction of the number of dividing CD4 + and CD8+ T cells and in the inhibition of virus isolation from purified CD4+ T-cell populations. Based on these results, the potential use of mycophenolate mophetil in the treatment of HIV infection deserves further investigation in controlled clinical trials.
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BACKGROUND: Individually, randomised trials have not shown conclusively whether adjuvant chemotherapy benefits adult patients with localised resectable soft-tissue sarcoma.METHODS: A quantitative meta-analysis of updated data from individual patients from all available randomised trials was carried out to assess whether adjuvant chemotherapy improves overall survival, recurrence-free survival, and local and distant recurrence-free intervals (RFI) and whether chemotherapy is differentially effective in patients defined by age, sex, disease status at randomisation, disease site, histology, grade, tumour size, extent of resection, and use of radiotherapy.FINDINGS: 1568 patients from 14 trials of doxorubicin-based adjuvant chemotherapy were included (median follow-up 9.4 years). Hazard ratios of 0.73 (95% CI 0.56-0.94, p = 0.016) for local RFI, 0.70 (0.57-0.85, p = 0.0003) for distant RFI, and 0.75 (0.64-0.87, p = 0.0001) for overall recurrence-free survival, correspond to absolute benefits from adjuvant chemotherapy of 6% (95% CI 1-10), 10% (5-15), and 10% (5-15), respectively, at 10 years. For overall survival the hazard ratio of 0.89 (0.76-1.03) was not significant (p = 0.12), but represents an absolute benefit of 4% (1-9) at 10 years. These results were not affected by prespecified changes in the groups of patients analysed. There was no consistent evidence that the relative effect of adjuvant chemotherapy differed for any subgroup of patients for any endpoint. However, the best evidence of an effect of adjuvant chemotherapy for survival was seen in patients with sarcomas of the extremities.INTERPRETATION: The meta-analysis provides evidence that adjuvant doxorubicin-based chemotherapy significantly improves the time to local and distant recurrence and overall recurrence-free survival. There is a trend towards improved overall survival.
Resumo:
Pattern recognition receptors (PRRs) are commonly known as sensor proteins crucial for the early detection of microbial or host-derived stress signals by innate immune cells. Interestingly, some PRRs are also expressed and functional in cells of the adaptive immune system. These receptors provide lymphocytes with innate sensing abilities; for example, B cells express Toll-like receptors, which are important for the humoral response. Strikingly, certain other NOD-like receptors are not only highly expressed in adaptive immune cells, but also exert functions related specifically to adaptive immune system pathways, such as regulating antigen presentation. In this review, we will focus particularly on the current understanding of PRR functions intrinsic to B and T lymphocytes; a developing aspect of PRR biology.
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BACKGROUND: Optic perineuritis (OPN) is an inflammatory condition involving the optic nerve sheath because of a variety of causes. We describe three patients in whom OPN was secondary to Wegener's granulomatosis (WG) and compare the clinical findings in these cases with those of idiopathic OPN. METHODS: This is a retrospective small case series derived from patients with OPN seen in an outpatient neuro-ophthalmology clinic. Medical records and imaging studies of these patients were reviewed. RESULTS: These patients shared clinical similarities with idiopathic OPN including age, sex, symptoms, radiographic findings and steroid responsiveness. However, recurrence of symptoms on lowering the prednisone dose below 40 mg distinguished these patients from those with idiopathic OPN. CONCLUSIONS: Steroid dependency in idiopathic OPN should raise suspicion of WG. Patients with OPN should be specifically questioned regarding pre-existing upper respiratory tract disorders and rheumatic symptoms and laboratory testing should include acute phase reactants, anti-neutrophil cytoplasmic antibodies and tests of renal function.
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L'utilisation des traitements biologiques est maintenant solidement ancrée dans la prise en charge des rhumatismes inflammatoires. Les anti-TNFa sont à juste titre devenus des agents de choix ces dix dernières années, et la littérature récente nous rappelle leurs places et indications dans la spondylarthrite ankylosante. Toutefois, tous les patients n'y répondent pas et la disponibilité de nouveaux traitements est certainement une addition bienvenue. L'abatacept est un nouveau traitement de la polyarthrite rhumatoïde avec un mode daction innovateur, qui paraît efficace et adéquatement sûr et pour lequel quelques données et aspects pratiques d'utilisation sont présentés. Nous devons néanmoins encore apprendre à l'intégrer dans des stratégies thérapeutiques, comme nous sommes en train de le faire avec le rituximab. The use of biological therapy is now firmly established in the management of inflammatory rheumatism. The anti-TNFalpha have rightly become agents of choice over the last 10 years, and the recent literature reminds us of their places and indications in ankylosing spondylitis. However, not all patients respond, and the availability of new treatments is certainly a welcome addition. Abatacept is a new treatment for rheumatoid arthritis with an innovative mode of action. It appears effective and safe, and some data as well as practical aspects on its use are presented. Nevertheless, we must still learn to integrate it into our therapeutic strategies, as we are presently doing with rituximab
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Central serous chorioretinopathy (CSCR) is a vision-threatening eye disease with no validated treatment and unknown pathogeny. In CSCR, dilation and leakage of choroid vessels underneath the retina cause subretinal fluid accumulation and retinal detachment. Because glucocorticoids induce and aggravate CSCR and are known to bind to the mineralocorticoid receptor (MR), CSCR may be related to inappropriate MR activation. Our aim was to assess the effect of MR activation on rat choroidal vasculature and translate the results to CSCR patients. Intravitreous injection of the glucocorticoid corticosterone in rat eyes induced choroidal enlargement. Aldosterone, a specific MR activator, elicited the same effect, producing choroid vessel dilation -and leakage. We identified an underlying mechanism of this effect: aldosterone upregulated the endothelial vasodilatory K channel KCa2.3. Its blockade prevented aldosterone-induced thickening. To translate these findings, we treated 2 patients with chronic nonresolved CSCR with oral eplerenone, a specific MR antagonist, for 5 weeks, and observed impressive and rapid resolution of retinal detachment and choroidal vasodilation as well as improved visual acuity. The benefit was maintained 5 months after eplerenone withdrawal. Our results identify MR signaling as a pathway controlling choroidal vascular bed relaxation and provide a pathogenic link with human CSCR, which suggests that blockade of MR could be used therapeutically to reverse choroid vasculopathy.
Resumo:
AA-amyloidosis in the setting of chronic visceral leishmaniasis (VL) has been reported in animal models but documentation in humans is unavailable. Here, we report on a Portuguese man who in 1996 was diagnosed with both human immunodeficiency virus (HIV)-infection and VL. Antiretroviral treatment led to sustained suppression of HIV viremia but CD4+ lymphocytes rose from 8 to only 160 cells/mL. Several courses of antimony treatment did not prevent VL relapses. Renal failure developed in 2006 and renal biopsy revealed AA-amyloidosis. The patient had cryoglobulinemia and serum immune complexes containing antibodies directed against seven leishmanial antigens. Antimony plus amphotericin B, followed by oral miltefosine resulted in a sustained VL treatment response with elimination of circulating Leishmania infantum DNA and CD4+ recovery. The concomitant reduction of serum AA levels and disappearance of circulating leishmanial immune complexes suggests that prolonged VL may lead to AA-amyloidosis in immunocompromised humans.
Quantifying uncertainty: physicians' estimates of infection in critically ill neonates and children.
Resumo:
To determine the diagnostic accuracy of physicians' prior probability estimates of serious infection in critically ill neonates and children, we conducted a prospective cohort study in 2 intensive care units. Using available clinical, laboratory, and radiographic information, 27 physicians provided 2567 probability estimates for 347 patients (follow-up rate, 92%). The median probability estimate of infection increased from 0% (i.e., no antibiotic treatment or diagnostic work-up for sepsis), to 2% on the day preceding initiation of antibiotic therapy, to 20% at initiation of antibiotic treatment (P<.001). At initiation of treatment, predictions discriminated well between episodes subsequently classified as proven infection and episodes ultimately judged unlikely to be infection (area under the curve, 0.88). Physicians also showed a good ability to predict blood culture-positive sepsis (area under the curve, 0.77). Treatment and testing thresholds were derived from the provided predictions and treatment rates. Physicians' prognoses regarding the presence of serious infection were remarkably precise. Studies investigating the value of new tests for diagnosis of sepsis should establish that they add incremental value to physicians' judgment.
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BACKGROUND: Conventional therapy with beta-blockers is incompletely effective in preventing arrhythmic events in patients with catecholaminergic polymorphic ventricular tachycardia (CPVT). We have previously discovered that flecainide in addition to conventional drug therapy prevents ventricular arrhythmias in patients with genotype-positive CPVT. OBJECTIVE: To study the efficacy of flecainide in patients with genotype-negative CPVT. METHODS: We studied the efficacy of flecainide for reducing ventricular arrhythmias during exercise testing and preventing arrhythmia events during long-term follow-up. RESULTS: Twelve patients with genotype-negative CPVT were treated with flecainide. Conventional therapy failed to control ventricular arrhythmias in all patients. Flecainide was initiated because of significant ventricular arrhythmias (n = 8), syncope (n = 3), or cardiac arrest (n = 1). At the baseline exercise test before flecainide, 6 patients had ventricular tachycardia and 5 patients had bigeminal or frequent ventricular premature beats. Flecainide reduced ventricular arrhythmias at the exercise test in 8 patients compared to conventional therapy, similar to that in patients with genotype-positive CPVT in our previous report. Notably, flecainide completely prevented ventricular arrhythmias in 7 patients. Flecainide was continued in all patients except for one who had ventricular tachycardia at the exercise test on flecainide. During a follow-up of 48±94 months, arrhythmia events (sudden cardiac death and aborted cardiac arrest) associated with noncompliance occurred in 2 patients. Flecainide was not discontinued owing to side effects in any of the patients. CONCLUSIONS: Flecainide was effective in patients with genotype-negative CPVT, suggesting that spontaneous Ca(2+) release from ryanodine channels plays a role in arrhythmia susceptibility, similar to that in patients with genotype-positive CPVT.
Resumo:
Cet article présente les résultats de la revue systématique: Musini VM, Tejani AM, Bassett K, Wright JM. Pharmacotherapy for hypertension in the elderly. Cochrane Database Syst Rev. 2009 Oct 7;(4):CD000028. PMID: 19821263
Resumo:
Juvenile spondylarthropathies (JSpAs) comprise a group of rheumatic diseases distinct from other categories of juvenile arthritis. Several classification systems have been applied, and some are specific for children, such as the seronegative enthesopathy and arthropathy (SEA) syndrome and the enthesitis-related arthritis, diagnostic forms in the International League of Associations for Rheumatism (ILAR) classification. JSpA seems more frequent than was previously believed, but actual epidemiological data show important variations between studies. Compared to adult patients, children with JSpA present with peripheral arthritis and enthesitis early in disease but sacroiliac and spine joints involvement many years later. A multidisciplinary team in a paediatric environment should be responsible for the management of children with spondylarthropathies to ensure the best care for these children with their chronic disease and risk of long-term disability. Recent advances in the treatment of rheumatic diseases with biological agents show promising results in children with JSpA. Further research needs to be conducted to increase our knowledge of the long-term outcome of these patients, to improve management, and to prevent long-term consequences of the disease.