917 resultados para Benefit of continued installment


Relevância:

100.00% 100.00%

Publicador:

Resumo:

A large proportion of soybean fields in Brazil are currently cultivated in the Cerrado region, where the area planted with this crop is growing considerably every year. Soybean cultivation in acid soils is also increasing worldwide. Since the levels of toxic aluminum (Al) in these acid soils is usually high it is important to understand how cations can reduce Al rhizotoxicity in soybean. In the present study we evaluated the ameliorative effect of nine divalent cations (Ca, Mg, Mn, Sr, Sn, Cu, Zn, Co and Ba) in solution culture on Al rhizotoxicity in soybean. The growth benefit of Ca and Mg to plants in an acid Inceptisol was also evaluated. In this experiment soil exchangeable Ca:Mg ratios were adjusted to reach 10 and 60 % base saturation, controlled by different amounts of CaCl2 or MgCl2 (at proportions from 100:0 up to 0:100), without altering the soil pH level. The low (10 %) and adequate (60 %) base saturation were used to examine how plant roots respond to Al at distinct (Ca + Mg)/Al ratios, as if they were growing in soils with distinct acidity levels. Negative and positive control treatments consisted of absence (under native soil or undisturbed conditions) or presence of lime (CaCO3) to reach 10 and 60 % base saturation, respectively. It was observed that in the absence of Aluminum, Cu, Zn, Co and Sn were toxic even at a low concentration (25 µmol L-1), while the effect of Mn, Ba, Sr and Mg was positive or absent on soybean root elongation when used in concentrations up to 100 µmol L-1. At a level of 10 µmol L-1 Al, root growth was only reverted to the level of control plants by the Mg treatment. Higher Tin doses led to a small alleviation of Al rhizotoxicity, while the other cations reduced root growth or had no effect. This is an indication that the Mg effect is ion-specific and not associated to an electrostatic protection mechanism only, since all ions were divalent and used at low concentrations. An increased exchangeable Ca:Mg ratio (at constant soil pH) in the acid soil almost doubled the soybean shoot and root dry matter even though treatments did not modify soil pH and exchangeable Al3+. This indicates a more efficient alleviation of Al toxicity by Mg2+ than by Ca2+. The reason for the positive response to Mg2+ was not the supply of a deficient nutrient because CaCO3 increased soybean growth by increasing soil pH without inducing Mg2+ deficiency. Both in hydroponics and acid soil, the reduction in Al toxicity was accompanied by a lower Al accumulation in plant tissue, suggesting a competitive cation absorption and/or exclusion of Al from plant tissue stimulated by an Mg-induced physiological mechanism.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Introduction: Imatinib trough plasma concentrations (Cmin) have been correlated with treatment response in chronic myeloid leukemia (CML) patients. The use of Cmin monitoring for optimizing imatinib dosage (therapeutic drug monitoring [TDM]) is therefore proposed for patients with unsatisfying response or tolerance ("rescue TDM"). A cycle of "routine TDM" for dosage individualization could also be beneficial to prevent unfavorable events, yet its clinical usefulness has not been evaluated. We aimed to assess prospectively whether a "routine TDM" intervention targeting imatinib Cmin of 1000 ng/mL (tolerance, 750-1500 ng/mL) could improve efficacy, tolerance, and persistence on treatment compared with "rescue TDM" use only. Patients (or Materials) and Methods: The Swiss Imatinib COncentration Monitoring Evaluation (I-COME) study was a multicenter randomized controlled trial (ISRCTN31181395). Adult patients in chronic or accelerated phase CML receiving imatinib ≤5 years were eligible. Patients were randomly (1:1) allocated to receive "routine TDM" intervention or to serve as controls with access only to "rescue TDM". All had 1-year follow-up. The primary endpoint was a combined efficacy-safety outcome (failure- and toxicity-free survival without imatinib discontinuation), analyzed in intention-to-treat. Results: Among 56 CML recruited patients, 55 had their molecular and cytogenetic response measured. 14/27 of patients receiving "routine TDM" (52% [33%-71%]) remained event-free versus 16/28 of control patients with "rescue TDM" only (57% [39%-75%]; P=0.69). In the "routine TDM" group, dosage recommendations were adopted entirely in 50% of patients (median Cmin at study end, 895 ng/mL; CV = 33%). These patients had fewer unfavorable events (28% [5%-52%]) compared with patients not receiving the advised dosage (77% [54%-99%]; P = 0.03; median Cmin at study end, 648 ng/mL; CV = 38%). Conclusion: This first prospective target concentration intervention trial could not formally demonstrate a benefit of "routine TDM" of imatinib, especially due to a small patient number and limited prescriber's adherence to dosage recommendations. Nevertheless, the patients receiving the advised dosage more often met target concentrations and the combined outcome (efficacy, tolerance, and persistence). A cycle of routine TDM could thus be favorable, at least in patients eligible for dosage adjustment. Its usefulness should, however, be further confirmed in larger trials.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A sustainable management of soils with low natural fertility on family farms in the humid tropics is a great challenge and overcoming it would be an enormous benefit for the environment and the farmers. The objective of this study was to assess the environmental and agronomic benefits of alley cropping, based on the evaluation of C sequestration, soil quality indicators, and corn yields. Combinations of four legumes were used in alley cropping systems in the following treatments: Clitoria fairchildiana + Cajanus cajan; Acacia mangium + Cajanus cajan; Leucaena leucocephala + Cajanus cajan; Clitoria fairchildiana + Leucaena leucocephala; Leucaena leucocephala + Acacia mangium and a control. Corn was used as a cash crop. The C content was determined in the different compartments of soil organic matter, CEC, available P, base saturation, percentage of water saturation, the period of the root hospitality factor below the critical level and corn yield. It was concluded that alley cropping could substitute the slash and burn system in the humid tropics. The main environmental benefit of alley cropping is the maintenance of a dynamic equilibrium between C input and output that could sustain up to 10 Mg ha-1 of C in the litter layer, decreasing atmospheric CO2 levels. Alley cropping is also beneficial from the agricultural point of view, because it increases base saturation and decreases physical resistance to root penetration in the soil layer 0 - 10 cm, which ensures the increase and sustainability of corn yield.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Pulmonary embolism (PE) is traditionally treated in hospital. Growing evidence from non randomized prospective studies suggests that a substantial proportion of patients with non-massive PE might be safely treated in the outpatient setting using low molecular weight heparins. Based on this evidence, professional societies started to recommend outpatient care for selected patients with non-massive PE. Despite these recommendations, outpatient treatment of non-massive PE appears to be uncommon in clinical practice. The major barriers to PE outpatient care are, firstly, the uncertainty as how to identify low risk patients with PE who are candidates for outpatient care and secondly the lack of high quality evidence from randomized trials demonstrating the safety of PE outpatient care compared to traditional inpatient management. Also, although clinical prognostic models, echocardiography and cardiac biomarkers accurately identify low risk patients with PE in prospective studies, the benefit of risk stratification strategies based on these instruments should be demonstrated in prospective management studies and clinical trials before they can be implemented as decision aids to guide PE outpatient treatment. Before high quality evidence documenting the safety of an outpatient treatment approach is published, outpatient management of non-massive PE cannot be generally recommended.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Background In angioimmunoblastic T-cell lymphoma, symptoms linked to B-lymphocyte activation are common, and variable numbers of CD20(+) large B-blasts, often infected by Epstein-Barr virus, are found in tumor tissues. We postulated that the disruption of putative B-T interactions and/or depletion of the Epstein-Barr virus reservoir by an anti-CD20 monoclonal antibody (rituximab) could improve the clinical outcome produced by conventional chemotherapy. DESIGN AND METHODS: Twenty-five newly diagnosed patients were treated, in a phase II study, with eight cycles of rituximab + chemotherapy (R-CHOP21). Tumor infiltration, B-blasts and Epstein-Barr virus status in tumor tissue and peripheral blood were fully characterized at diagnosis and were correlated with clinical outcome. RESULTS: A complete response rate of 44% (95% CI, 24% to 65%) was observed. With a median follow-up of 24 months, the 2-year progression-free survival rate was 42% (95% CI, 22% to 61%) and overall survival rate was 62% (95% CI, 40% to 78%). The presence of Epstein-Barr virus DNA in peripheral blood mononuclear cells (14/21 patients) correlated with Epstein-Barr virus score in lymph nodes (P<0.004) and the detection of circulating tumor cells (P=0.0019). Despite peripheral Epstein-Barr virus clearance after treatment, the viral load at diagnosis (>100 copy/μg DNA) was associated with shorter progression-free survival (P=0.06). Conclusions We report here the results of the first clinical trial targeting both the neoplastic T cells and the microenvironment-associated CD20(+) B lymphocytes in angioimmunoblastic T-cell lymphoma, showing no clear benefit of adding rituximab to conventional chemotherapy. A strong relationship, not previously described, between circulating Epstein-Barr virus and circulating tumor cells is highlighted.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

In birds, sibling competition encompasses several activities, one of which is jostling for position, that is, competing for the location in the nest where parents predictably deliver food items. We hypothesized that nestlings that compete by jostling for position may fall out of the nest either accidentally or because siblings push each other to reduce brood size. This hypothesis predicts that in a competitive environment needy nestlings trade-off the benefit of being fed against the cost of falling out of the nest. As a first attempt to evaluate this hypothesis, we experimentally manipulated the number of young per brood in the colonial Alpine swift, Apus melba. Nestlings fell out of their colony more frequently when reared in enlarged than in reduced broods. Because brood size manipulation affects not only the number of young per nest but also their body condition, we analysed an extended data set to disentangle these two factors. This analysis showed that, independently of brood size, nestlings in poor condition and those reared in broods where sibling differed markedly in weight were more likely to disappear from the colony. Nestling disappearance also occurred predominantly in nests close to the colony entrances. Although nestling swifts can wander in the colony and become adopted in neighbouring nests, we found no evidence that wandering per se increased the risk of falling out of the colony. Our study therefore highlights a novel cost of scramble competition.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

A key, yet often neglected, component of digital evolution and evolutionary models is the 'selection method' which assigns fitness (number of offspring) to individuals based on their performance scores (efficiency in performing tasks). Here, we study with formal analysis and numerical experiments the evolution of cooperation under the five most common selection methods (proportionate, rank, truncation-proportionate, truncation-uniform and tournament). We consider related individuals engaging in a Prisoner's Dilemma game where individuals can either cooperate or defect. A cooperator pays a cost, whereas its partner receives a benefit, which affect their performance scores. These performance scores are translated into fitness by one of the five selection methods. We show that cooperation is positively associated with the relatedness between individuals under all selection methods. By contrast, the change in the performance benefit of cooperation affects the populations' average level of cooperation only under the proportionate methods. We also demonstrate that the truncation and tournament methods may introduce negative frequency-dependence and lead to the evolution of polymorphic populations. Using the example of the evolution of cooperation, we show that the choice of selection method, though it is often marginalized, can considerably affect the evolutionary dynamics.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Bien que les activités où la compétence est un enjeu (p. ex. : problème académique) prennent souvent place dans des contextes interpersonnels (p. ex. : classe), hiérarchiques (p. ex. : enseignant-e/élèves), et spécifiques en termes de normes et de valeurs (p. ex. : culture), l'étude des buts de performance-le désir de se montrer compétent-e relativement à autrui-a le plus souvent été conduite au seul niveau intrapersonnel. S'appuyant sur le modèle transactionnel du stress et du coping, le modèle circumplexe des comportements interpersonnels, ainsi que sur la théorie de l'élaboration du conflit, la première partie de cette thèse révèle les conséquences interpersonnelles des buts de performance sur la régulation d'un comportement spécifique, à savoir le conflit sociocognitif (c.-à-d., une situation de confrontation avec un intéractant en désaccord) : les buts de performance-approche-le désir d'être meilleur-e qu'autrui-prédisent une régulation du conflit fortement agentique (dominante), soit la validation de son point de vue au détriment de celui de l'intéractant (que nous désignons régulation compétitive) ; alors que les buts de performance-évitement-le désir de ne pas être moins bon-ne qu'autrui-prédisent une régulation du conflit faiblement agentique (soumise), soit l'invalidation de son point de vue au bénéfice de celui de l'intéractant (que nous désignons régulation protective). De plus, les effets susmentionnés augmentent à mesure que l'intéractant est présenté comme supérieurement (vs. similairement) compétent. S'appuyant sur la littérature sur les structures de buts de groupe, et celle sur la socialisation des valeurs, la seconde partie de cette thèse révèle les antécédents interpersonnels des buts de performance, et plus spécifiquement le rôle du superviseur dans la socialisation des buts de performance : les buts de performance-approche d'un superviseur sont positivement associés avec l'émergence au cours du temps des buts de performance-approche de ses subordonnés (particulièrement lorsqu'ils se perçoivent comme compétents) et celle de leurs buts de performance-évitement (particulièrement lorsqu'ils se perçoivent comme incompétents). En outre, ce phénomène consistant en un processus de socialisation, les effets susmentionnés augmentent lorsque l'identification à l'endogroupe des subordonnées augmente, et lorsque l'adhésion aux valeurs culturelles occidentales dominantes (c.-à-d., rehaussement de soi) du superviseur augmente. Dans leur ensemble, ces résultats soulignent la nécessité d'étudier les buts dans leur plenum social, autrement dit, en adoptant une perspective interpersonnelle (c.-à-d., étudier les effets des buts entre les individus), positionnelle (c.-à-d., entre des individus de différentes positions sociales), et idéologique (c.- à-d., entre des individus se conformant à des normes spécifiques et adhérant à des valeurs spécifiques). -- Although competence-relevant activities (e.g., solving an academic problem) are often embedded in interpersonal (e.g., classroom), hierarchical (e.g., teacher/pupils), and norm-/value-specific (e.g., culture) settings, the study of performance goals-the desire to demonstrate competence relative to others-has mostly been conducted at the intrapersonal level alone. Drawing on the transactional model of stress and coping, the circumplex model of interpersonal behaviors, as well as on the conflict elaboration theory, the first part of this thesis reveals the interpersonal consequences of performance goals on the regulation of a specific behavior, namely socio-cognitive conflict (i.e., a situation of confrontation with a disagreeing interactant): Performance-approach goals-the desire to outperform others- predicted a highly agentic (dominant) conflict regulation, that is, the validation of one's point of view at the expense of that of the interactant (which we labeled competitive regulation); whereas performance-avoidance goals-the desire not to be outperformed by others- predicted a poorly agentic (submissive) conflict regulation, that is, the invalidation of one's point of view to the benefit of that of the interactant (which we labeled protective regulation). Furthermore, both the aforementioned effects were found to increase when the interactant was presented as being superiorly (vs. equally) in competence. Drawing on the literature on group goal structure, as well as on research on socialization of supervisors-based values, the second part of this thesis reveals the interpersonal antecedents of performance-based goals endorsement, focusing-more specifically-on the role of group-supervisors in performance goals socialization: Supervisor's performance-approach goals were positively associated with the emergence over time of subordinates' performance-approach (especially when perceiving themselves as competent) and -avoidance goals (especially when perceiving themselves as incompetent). Furthermore, providing evidence that this phenomenon essentially reflects a socialization process, both the aforementioned effects were found to increase as subordinates' in-group identification increased, and as supervisors' adherence to dominant Western values (i.e., self-enhancement values) increased. Taken together, these results advocate the need to study performance goals in their social plenum, that is, adopting an interpersonal (i.e., studying the effects of goals between individuals), positional (i.e., between individuals from different social positions), and ideological (i.e., between individuals following specific norms and endorsing specific values) perspective.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

(from the journal abstract) Background: Despite the effectiveness of anti-psychotic pharmacotherapy, residual hallucinations and delusions do not completely resolve in some medicated patients. Additional cognitive behavioral therapy (CBT) seems to improve the management of positive symptoms. Despite promising results, the efficacy of CBT is still unclear. The present study addresses this issue taking into account a number of newly published controlled studies. Method: Fourteen studies including 1484 patients, published between 1990 and 2004 were identified and a meta-analysis of their results performed. Results: Compared to other adjunctive measures, CBT showed significant reduction in positive symptoms and there was a higher benefit of CBT for patients suffering an acute psychotic episode versus the chronic condition (effect size of 0.57 vs. 0.27). Discussion: CBT is a promising adjunctive treatment for positive symptoms in schizophrenia spectrum disorders. However, a number of potentially modifying variables have not yet been examined, such as therapeutic alliance and neuropsychological deficits. (PsycINFO Database Record (c) 2005 APA, all rights reserved)

Relevância:

100.00% 100.00%

Publicador:

Resumo:

BACKGROUND: In 2004, a randomised phase III trial by the European Organisation for Research and Treatment of Cancer (EORTC) and National Cancer Institute of Canada Clinical Trials Group (NCIC) reported improved median and 2-year survival for patients with glioblastoma treated with concomitant and adjuvant temozolomide and radiotherapy. We report the final results with a median follow-up of more than 5 years. METHODS: Adult patients with newly diagnosed glioblastoma were randomly assigned to receive either standard radiotherapy or identical radiotherapy with concomitant temozolomide followed by up to six cycles of adjuvant temozolomide. The methylation status of the methyl-guanine methyl transferase gene, MGMT, was determined retrospectively from the tumour tissue of 206 patients. The primary endpoint was overall survival. Analyses were by intention to treat. This trial is registered with Clinicaltrials.gov, number NCT00006353. FINDINGS: Between Aug 17, 2000, and March 22, 2002, 573 patients were assigned to treatment. 278 (97%) of 286 patients in the radiotherapy alone group and 254 (89%) of 287 in the combined-treatment group died during 5 years of follow-up. Overall survival was 27.2% (95% CI 22.2-32.5) at 2 years, 16.0% (12.0-20.6) at 3 years, 12.1% (8.5-16.4) at 4 years, and 9.8% (6.4-14.0) at 5 years with temozolomide, versus 10.9% (7.6-14.8), 4.4% (2.4-7.2), 3.0% (1.4-5.7), and 1.9% (0.6-4.4) with radiotherapy alone (hazard ratio 0.6, 95% CI 0.5-0.7; p<0.0001). A benefit of combined therapy was recorded in all clinical prognostic subgroups, including patients aged 60-70 years. Methylation of the MGMT promoter was the strongest predictor for outcome and benefit from temozolomide chemotherapy. INTERPRETATION: Benefits of adjuvant temozolomide with radiotherapy lasted throughout 5 years of follow-up. A few patients in favourable prognostic categories survive longer than 5 years. MGMT methylation status identifies patients most likely to benefit from the addition of temozolomide. FUNDING: EORTC, NCIC, Nélia and Amadeo Barletta Foundation, Schering-Plough.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

ABSTRACT : Background : The aim of this study was to evaluate the midterm biocompatibility of a new x-shaped implant made of zirconium in an animal model of glaucoma surgery. Methods : Preoperatively, ultrasound biomicroscopy (UBM), intraocular pressure (IOP) and outflow facility (OF) data were acquired. Upon surgery, one eye was chosen randomly to receive an implant, while the other received none. Ten rabbits went through a 1-, 2-, 3-, 4- and 6-month follow-up. [OP was measured regularly, UBM performed at 1, 3 and 6 months after surgery. At the end of the follow-up, OF was again measured. Histology sections were analyzed. Results : For both groups IOP control was satisfactory, while OF initially increased at month 1 to resume preoperative values thereafter. Eyes with implants had larger filtration blebs which decreased faster than in eyes without the implant. Drainage vessel density, inflammatory cell number and fibrosis were higher in tissues near the implant. Conclusions : The zirconium implant initially promoted the positive effects of the surgery (IOP control, OF increase). Nevertheless, after several months, foreign body reactions and fibrosis had occurred on some implants that restrained the early benefit of such a procedure. Modifications of the zirconium implant geometry could enhance the overall success rate.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

PURPOSE: To centrally assess estrogen receptor (ER) and progesterone receptor (PgR) levels by immunohistochemistry and investigate their predictive value for benefit of chemo-endocrine compared with endocrine adjuvant therapy alone in two randomized clinical trials for node-negative breast cancer. PATIENTS AND METHODS: International Breast Cancer Study Group Trial VIII compared cyclophosphamide, methotrexate, and fluorouracil (CMF) chemotherapy for 6 cycles followed by endocrine therapy with goserelin with either modality alone in pre- and perimenopausal patients. Trial IX compared three cycles of CMF followed by tamoxifen for 5 years versus tamoxifen alone in postmenopausal patients. Central Pathology Office reviewed 883 (83%) of 1,063 patients on Trial VIII and 1,365 (82%) of 1,669 on Trial IX and determined ER and PgR by immunohistochemistry. Disease-free survival (DFS) was compared across the spectrum of expression of each receptor using the Subpopulation Treatment Effect Pattern Plot methodology. RESULTS: Both receptors displayed a bimodal distribution, with substantial proportions showing no staining (receptor absent) and most of the remainder showing a high percentage of stained cells. Chemo-endocrine therapy yielded DFS superior to endocrine therapy alone for patients with receptor-absent tumors, and in some cases also for those with low levels of receptor expression. Among patients with ER-expressing tumors, additional prediction of benefit was suggested in absent or low PgR in Trial VIII but not in Trial IX. CONCLUSION: Low levels of ER and PgR are predictive of the benefit of adding chemotherapy to endocrine therapy. Low PgR may add further prediction among pre- and perimenopausal but not postmenopausal patients whose tumors express ER.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

BACKGROUND: Whole pelvis intensity modulated radiotherapy (IMRT) is increasingly being used to treat cervical cancer aiming to reduce side effects. Encouraged by this, some groups have proposed the use of simultaneous integrated boost (SIB) to target the tumor, either to get a higher tumoricidal effect or to replace brachytherapy. Nevertheless, physiological organ movement and rapid tumor regression throughout treatment might substantially reduce any benefit of this approach. PURPOSE: To evaluate the clinical target volume - simultaneous integrated boost (CTV-SIB) regression and motion during chemo-radiotherapy (CRT) for cervical cancer, and to monitor treatment progress dosimetrically and volumetrically to ensure treatment goals are met. METHODS AND MATERIALS: Ten patients treated with standard doses of CRT and brachytherapy were retrospectively re-planned using a helical Tomotherapy - SIB technique for the hypothetical scenario of this feasibility study. Target and organs at risk (OAR) were contoured on deformable fused planning-computed tomography and megavoltage computed tomography images. The CTV-SIB volume regression was determined. The center of mass (CM) was used to evaluate the degree of motion. The Dice's similarity coefficient (DSC) was used to assess the spatial overlap of CTV-SIBs between scans. A cumulative dose-volume histogram modeled estimated delivered doses. RESULTS: The CTV-SIB relative reduction was between 31 and 70%. The mean maximum CM change was 12.5, 9, and 3 mm in the superior-inferior, antero-posterior, and right-left dimensions, respectively. The CTV-SIB-DSC approached 1 in the first week of treatment, indicating almost perfect overlap. CTV-SIB-DSC regressed linearly during therapy, and by the end of treatment was 0.5, indicating 50% discordance. Two patients received less than 95% of the prescribed dose. Much higher doses to the OAR were observed. A multiple regression analysis showed a significant interaction between CTV-SIB reduction and OAR dose increase. CONCLUSIONS: The CTV-SIB had important regression and motion during CRT, receiving lower therapeutic doses than expected. The OAR had unpredictable shifts and received higher doses. The use of SIB without frequent adaptation of the treatment plan exposes cervical cancer patients to an unpredictable risk of under-dosing the target and/or overdosing adjacent critical structures. In that scenario, brachytherapy continues to be the gold standard approach.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Aims: Recently, several clinical trials analyzed if extended duration of treatment with pegylated interferon-alfa and ribavirin over 48 weeks can improve sustained virologic response (SVR) rates in HCV genotype 1-infected patients with slow virologic response. Because results of these clinical trials are conflicting, we performed a metaanalysis to determine the overall impact of extended treatment compared to standard treatment on virologic response rates in treatment-naive HCV genotype 1 slow responders. Methods: Literature search was performed independently by two observers using Pub Med, EMBASE, CENTRAL and abstracts presented in English at international liver and gastroenterology meetings. Randomized controlled clinical trials (RCTs; but studies that re-analyzed data retrospectively RCTs were also allowed) were considered if they included monoinfected treatment-naive HCV genotype 1 patients and compared treatment with pegIFN-alfa 2a or 2b in combination with ribavirin for 48 weeks versus extended treatment (up to 72 weeks) in slow responders. Primary and secondary end points were SVR rates and end-of-treatment (EOT) and relapse rates, respectively. In the present meta-analysis, study endpoints were summarized with a DerSimonian-Laird estimate for binary outcome basing on a random effects model. Results: Literature search yielded seven RTCs addressing the benefit of extended treatment with pegylated interferon-alfa and ribavirin in treatment-naive HCV genotype 1 slow responders. In total, 1330 slow responders were included in our meta-analysis. We show that extended treatment duration compared to the standard of care significantly improves SVR rates in HCV genotype 1 slow responders (12.4% improvement of overall SVR rate, 95% CI 0.055- 0.193, P = 0.0005). In addition, we show that rates of viral relapse were significantly reduced by extended treatment (24.1% reduction of relapse, 95% CI −0.3332 to −0.1487, P < 0.0001), whereas no significant impact of extended treatment on EOT response rates was found. Though extended treatment was burdened with an enhanced rate of premature treatment discontinuation due to interferonalfa- and ribavirin-related side effects, the frequency of serious adverse events was not increased. Conclusions: Treatment extension in HCV genotype 1 slow responders can improve SVR rates in difficult to treat patients and should be considered in patients who need to be treated before specific antivirals will be approved.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

BACKGROUND: Pharmacotherapy may represent a potential means to limit the expansion rate of abdominal aortic aneurysms (AAAs). Studies evaluating the efficacy of different pharmacological agents to slow down human AAA-expansion rates have been performed, but they have never been systematically reviewed or summarized. METHODS AND FINDINGS: Two independent reviewers identified studies and selected randomized trials and prospective cohort studies comparing the growth rate of AAA in patients with pharmacotherapy vs. no pharmacotherapy. We extracted information on study interventions, baseline characteristics, methodological quality, and AAA growth rate differences (in mm/year). Fourteen prospective studies met eligibility criteria. Five cohort studies raised the possibility of benefit of beta-blockers [pooled growth rate difference: -0.62 mm/year, (95%CI, -1.00 to -0.24)], but this was not confirmed in three beta-blocker RCTs [pooled RCT growth rate difference: -0.05 mm/year (-0.16 to 0.05)]. Statins have been evaluated in two cohort studies that yield a pooled growth rate difference of -2.97 (-5.83 to -0.11). Doxycycline and roxithromycin have been evaluated in two RCTs that suggest possible benefit [pooled RCT growth rate difference: -1.32 mm/year (-2.89 to 0.25)]. Studies assessing NSAIDs, diuretics, calcium channel blockers and ACE inhibitors, meanwhile, did not find statistically significant differences. CONCLUSIONS: Beta-blockers do not appear to significantly reduce the growth rate of AAAs. Statins and other anti-inflammatory agents appear to hold promise for decreasing the expansion rate of AAA, but need further evaluation before definitive recommendations can be made.