66 resultados para Nonresponders
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Background Depression is a heterogeneous mental illness. Neurostimulation treatments, by targeting specific nodes within the brain’s emotion-regulation network, may be useful both as therapies and as probes for identifying clinically relevant depression subtypes. Methods Here, we applied 20 sessions of magnetic resonance imaging-guided repetitive transcranial magnetic stimulation (rTMS) to the dorsomedial prefrontal cortex in 47 unipolar or bipolar patients with a medication-resistant major depressive episode. Results Treatment response was strongly bimodal, with individual patients showing either minimal or marked improvement. Compared with responders, nonresponders showed markedly higher baseline anhedonia symptomatology (including pessimism, loss of pleasure, and loss of interest in previously enjoyed activities) on item-by-item examination of Beck Depression Inventory-II and Quick Inventory of Depressive Symptomatology ratings. Congruently, on baseline functional magnetic resonance imaging, nonresponders showed significantly lower connectivity through a classical reward pathway comprising ventral tegmental area, striatum, and a region in ventromedial prefrontal cortex. Responders and nonresponders also showed opposite patterns of hemispheric lateralization in the connectivity of dorsomedial and dorsolateral regions to this same ventromedial region. Conclusions The results suggest distinct depression subtypes, one with preserved hedonic function and responsive to dorsomedial rTMS and another with disrupted hedonic function, abnormally lateralized connectivity through ventromedial prefrontal cortex, and unresponsive to dorsomedial rTMS. Future research directly comparing the effects of rTMS at different targets, guided by neuroimaging and clinical presentation, may clarify whether hedonia/reward circuit integrity is a reliable marker for optimizing rTMS target selection.
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The combination of pegylated interferon (PEG-INF) and ribavirin is currently the best treatment for chronic hepatitis C, providing a sustained virological response (SVR) in 54%-63% of patients. In patients infected with hepatitis C virus (HCV) genotype 1, the SVR rate is 42%-52%. To evaluate the treatment efficacy of this drug combination, we conducted an open, prospective study of 58 consecutive treatment-naive patients infected with HCV genotype 1 and treated at a university hospital, comparing those presenting an SVR (SVRs), nonresponders (NRs), and relapsers (RELs). Among the intent-to-treat patients, an end-of-treatment virological response was achieved in 69 % of the sample as a whole and in 52 % of the SVRs. We found that being an SVR was significantly associated with mild fibrosis (p = 0.04) and with undetectable HCV RNA at weeks 12 and 24 of treatment (p < 0.0001). Comparing the SVR and REL groups, we observed that being older than 40 was significantly associated with being a REL (p = 0.04). Being an NR was found to be associated with severe fibrosis and moderate inflammatory infiltrates (portal or periportal). In the polytomous logistic regression, no independent factors were associated with the REL group when compared with the SVR group. We conclude that RELs and NRs differ in comparison with SVRs. The RELs accounted for 17% of the sample. The HCV RNA test results at weeks 12 and 24 of treatment, although independent predictors of non-response (OR: 4.8 and 8.2, respectively), did not differ between SVRs and RELs.
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Abstract Background:The treatment of bipolar disorder (BD) remains a challenge due to the complexity of the disease. Current guidelines represent an effort to assist clinicians in routine practice but have several limitations, particularly concerning long-term treatment. The ARIQUELI (efficacy and tolerability of the combination of lithium or aripiprazole in young bipolar non or partial responders to quetiapine monotherapy) study aims to evaluate two different augmentation strategies for quetiapine nonresponders or partial responders in acute and maintenance phases of BD treatment. Methods/Design: The ARIQUELI study is a single-site, parallel-group, randomized, outcome assessor-blinded trial. BD I patients according to the DSM-IV-TR, in depressive, manic/hypomanic or mixed episode, aged 18 to 40 years, are eligible. After diagnostic assessments, patients initiated treatment in phase I with quetiapine. Nonresponders or partial responders after 8 weeks are allocated into one of two groups, potentiated with either lithium (0.5 to 0.8 mEq/l) or aripiprazole (10 or 15 mg). Patients will be followed up for 8 weeks in phase I (acute treatment), 6 months in phase II (continuation treatment) and 12 months in phase III (maintenance treatment). Outcome assessors are blinded to the treatment. The primary outcome is the evaluation of changes in mean scores on the CGI-BP-M between baseline and the endpoint at the end of each study phase. Discussion: The ARIQUELI study is currently in progress, with patients undergoing acute treatment (phase I), potentiation (phase II) and maintenance (phase III). The study will be extended until January 2015. Trials comparing lithium and aripiprazole with potentiate treatment in young BD I nonresponders to quetiapine in monotherapy can provide relevant information on the safety of these drugs in clinical practice. Long-term treatment is an issue of great importance and should be evaluated further through more in-depth studies given that BD is a chronic disease. Trial registration: ClinicalTrials.gov identifier: NCT01710163
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This report focuses on the effects of cholesterol on the expression and function of the ATP-binding cassette (ABCB1, ABCG2 and ABCC2) and solute-linked carrier (SLCO1B1 and SLCO2B1) drug transporters with a particular focus on the potential impact of cholesterol on lipid-lowering drug disposition. Statins are the most active agents in the treatment of hypercholesterolemia. However, considerable interindividual variation exists in the response to statin therapy. Therefore, it would be huge progress if factors were identified that reliably differentiate between responders and nonresponders. Many studies have suggested that plasma lipid concentrations can affect drug disposition of compounds, such as ciclosporin and amphotericin B. Both compounds are able to affect the expression and function of ABC transporters. Although still speculative, these effects might be owing to the regulation of drug transporters by plasma cholesterol levels. Studies with normo- and hyper-cholesterolemic individuals, before and after atorvastatin treatment, have demonstrated that plasma cholesterol levels are correlated with drug transporter expression, as well as being related to atorvastatin`s cholesterol-lowering effect. The mechanism influencing the correlation between cholesterol levels and the expression and function of drug transporters remains unclear. Some studies provide strong evidence that nuclear receptors, such as the pregnane X receptor and the constitutive androstane receptor, mediate this effect. In the near future, pharmacogenomic studies with individuals in a pathological state should be performed in order to identify whether high plasma cholesterol levels might be a factor contributing to interindividual oral drug bioavailability.
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Objectives: To test the effectiveness, in the setting of primary health care, of verbal advice on exercise from a family physician (FP) combined with supporting written information. Design: A controlled trial with subjects allocated to a control group or one of two intervention groups using a balanced design based on day of the week. Setting: Ten general practices in Perth, Western Australia. Subjects: All sedentary patients consulting an FP. Intervention: Verbal advice on exercise from the FP and a pamphlet on exercise mailed to the patient's home address within 2 days of his/her visit to the doctor. Main outcome measure: Level of physical activity at followup. Results: 6,351 adult patients attending an FP practice completed a screening questionnaire, and 763 sedentary adults were recruited to the project. The response to follow-up, via a postal survey at 1, 6, and 12 months after the index consultation was 70%, 60%, and 57%, respectively. At 1 month a subsample of the control and intervention subjects were contacted for a telephone interview to verify self-reported levels of activity (n = 136). Treating all nonresponders as sedentary, at 1 month significantly more subjects in the combined intervention groups reported doing some physical activity (40%) compared with the control group (31%). Similarly, at 6 months, 30% of the control group and 38% of the combined intervention groups were now active. There was very little change at followup at 12 months (31% control and 36% intervention groups, respectively). Conclusion: A simple intervention aimed at the promotion of physical activity to sedentary patients in general practice can help reduce inactivity.
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Objectives: A controlled trial to compare the effectiveness of verbal advice from a family physician (FP) combined with either standard or tailored written information on physical activity in increasing the levels of physical activity in sedentary patients. Design: Sedentary patients (n = 763) were recruited through ten family practices and allocated to a control group or one of two intervention groups, Brief advice on physical activity was given by the FP during the consultation and either a standard or tailored pamphlet was mailed to the home address of patients assigned to the intervention groups within two days of their visit to the FP. Results: The response to follow-up, via a postal survey at one, six, and twelve months after the index consultation was 70%, 60%, and 57%, respectively. Treating all nonresponders as sedentary, the results revealed that although more tailored subjects reported some physical activity at each follow-up compared with the standard group, these differences were not significant, Furthermore, there was no significant difference in movement across the stages of readiness to exercise at follow-up between subjects in the tailored group who received material targeting their current stage (precontemplation or contemplation) and the standard group who received generic material that addressed both stages. Conclusion: These findings do not concur with the results from previous research in the areas of nutrition and smoking cessation where additional benefits were seen with a tailored intervention. Future research on the application of the principles of tailoring to the promotion of physical activity should focus on identifying which, if any, physical, social, psychological or environmental variables should be addressed to produce improved outcomes over and above the effects of well designed generic materials. (C) 1999 American Journal of Preventive Medicine.
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Objective: To pilot a single-patient trials (SPTs) service in general practice, designed to improve decision-making about long-term medications for chronic conditions. Design: 12-week within-patient, randomised, double-blind, placebo-controlled, crossover comparison of ibuprofen with paracetamol for osteoarthritis, involving three pairs of two-week treatment periods for each participating patient. Setting and patients: Patients attending an academic general practice with a clinical diagnosis of osteoarthritis, with pain of at least a month's duration severe enough to warrant consideration of long-term non-steroidal anti-inflammatory drug (NSAID) use. Main outcome measures: Pain and stiffness; measures of overall arthritis compared with previous fortnight; preference for NSAID at the end of each two-week treatment period; use of escape analgesia; side effects; and management changes as a result of the SPTs. Results: Eight of 14 patients completed SPTs. One was a clear responder to NSAIDs, five were non-responders, and two were indefinite. Of the five who were using NSAIDs before the SPT, two continued and three ceased using them. Clinically useful information assisted decision-making for all eight participants. Medication management changed for six. Conclusions: Single-patient trials can be successfully implemented in general practice and might be a valuable method for GPs to identify patients who respond to medication for chronic stable conditions such as osteoarthritis, in which individual response to medication is variable.
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Precis Women with recurrent vulvovaginal candidiasis (RVC) due to a polymorphism in codon 54 of the MBL2 gene respond better to fluconazole maintenance therapy than do women with other underlying causes. Objective To explain differences in response rates to maintenance therapy with fluconazole in women suffering from RVC by evaluating associations with a polymorphism in the gene coding for mannose-binding lectin (MBL). Design Follow-up study, neted case-control group. Setting Women attending vulvoginitis clinic for RVC. Population Women participating in a multicentric study in Belgium with a degressive dose of fluconazole for RVC (the ReCiDiF trial) were divided into good responders, intermediate responders and nonresponders according to the number of relapses they experienced during therapy. From 109 of these women with adequate follow-up data, vaginal lavage with 2 ml of saline were performed at the moment of a proven acute attack at inclusion in the study, before maintenance treatment was started. A buccal swab was obtained from 55 age-matched women without a history of Candida infections, serving as a control group. Methods Extracted DNA from buccal or vaginal cells was tested for codon 54 MBL2 gene polymorphism by polymerase chain reaction and endonuclease digestion. Main outcome measures Frequency of MBL2 condon 54 allele B in women with optimal or poor response to maintenance therapy in composition with controls. Results Women (n = 109) suffering from RVC were more likely to carry the variant MBL2 codon 54 allele B than control women (20 versus 6.6%, OR 3.4 [95% CI 1.3-8.2], P = 0.01). B alleles were present in 25% of the 36 women not suffering from any recurrence during the maintenance therapy with decreasing doses of fluconazole (OR 4.9 [95% CI 1.9-12.5], P = 0.0007 versus controls), in 20% of the 43 women with sporadic recurrences (OR 3.6 [95% CI 1.4-9.2], P = 0.007 versus controls) and in 15% of the 30 women who had to interrupt the treatment regimen due to frequent relapses (P = 0.097 versus controls). Conclusions The MBL2 codon 54 gene polymorphism is more frequent in Belgian women suffering from RVC than in controls. The presence of the B allele is associated with a superior response to fluconazole maintenance therapy as compared with RVC patients without this polymorphism. We conclude that RVC due to deficient MBL production is more easily helped with antifungal medication than is RVC due to some other mechanism.
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BACKGROUND: The arterial pulse pressure variation induced by mechanical ventilation (Delta PP) has been shown to be a predictor of fluid responsiveness. Until now, Delta PP has had to be calculated offline (from a computer recording or a paper printing of the arterial pressure curve), or to be derived from specific cardiac output monitors, limiting the widespread use of this parameter. Recently, a method has been developed for the automatic calculation and real-time monitoring of Delta PP using standard bedside monitors. Whether this method is to predict reliable predictor of fluid responsiveness remains to be determined. METHODS: We conducted a prospective clinical study in 59 mechanically ventilated patients in the postoperative period of cardiac surgery. Patients studied were considered at low risk for complications related to fluid administration (pulmonary artery occlusion pressure <20 mm Hg, left ventricular ejection fraction >= 40%). All patients were instrumented with an arterial line and a pulmonary artery catheter. Cardiac filling pressures and cardiac output were measured before and after intravascular fluid administration (20 mL/kg of lactated Ringer`s solution over 20 min), whereas Delta PP was automatically calculated and continuously monitored. RESULTS: Fluid administration increased cardiac output by at least 15% in 39 patients (66% = responders). Before fluid administration, responders and nonresponders were comparable with regard to right atrial and pulmonary artery occlusion pressures. In contrast, Delta PP was significantly greater in responders than in nonresponders, (17% +/- 3% vs 9% +/- 2%, P < 0.001). The Delta PP cut-off value of 12% allowed identification of responders with a sensitivity of 97% and a specificity of 95%. CONCLUSION: Automatic real-time monitoring of Delta PP is possible using a standard bedside rnonitor and was found to be a reliable method to predict fluid responsiveness after cardiac surgery. Additional studies are needed to determine if this technique can be used to avoid the complications of fluid administration in high-risk patients.
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In critically ill patients, it is important to predict which patients will have their systemic blood flow increased in response to volume expansion to avoid undesired hypovolemia and fluid overloading. Static parameters such as the central venous pressure, the pulmonary arterial occlusion pressure, and the left ventricular end-diastolic dimension cannot accurately discriminate between responders and nonresponders to a fluid challenge. In this regard, respiratory-induced changes in arterial pulse pressure have been demonstrated to accurately predict preload responsiveness in mechanically ventilated patients. Some experimental and clinical studies confirm the usefulness of arterial pulse pressure as a useful tool to guide fluid therapy in critically ill patients.
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Background & Aims: Treatment with peginterferon alfa and ribavirin produces a sustained virologic response (SVR) in approximately 60% of hepatitis C virus (HCV)-infected patients. Alternate options are needed for patients who relapse or do not respond to therapy. Methods: This prospective, international, multicenter, open-label study evaluated efficacy and safety of peginterferon alfa-2b (1.5 mu g/kg/wk) plus weight-based ribavirin (800-1400 mg/day) in 2333 chronic HCV-infected patients with significant fibrosis/cirrhosis whose previous interferon alfa/ribavirin therapy failed. Patients with undetectable HCV-RNA at treatment week (TW) 12 received 48 weeks of therapy; patients with detectable HCV-RNA at TW12 could enter maintenance studies at TW18; 188 patients with low/detectable HCV-RNA at TW12 continued therapy at the investigator`s request. Results: Overall, 22% of the patients attained SVR (56% with undetectable HCV-RNA and 12% with low/detectable HCV-RNA at TW12). SVR was better in relapsers (38%) than nonresponders (14%), regardless of previous treatment, and in patients previously treated with interferon-alfa/ribavirin (25%) than peginterferon alfa-ribavirin (17%). Predictors of response in patients with undetectable HCV-RNA at TW12 were genotype (2/3 vs 1, respectively; odds ratio [OR] 2.4; P < .0001), fibrosis score (F2 vs F4; OR, 2.2; F3 vs F4; OR, 1.7; P < .0001), and baseline viral load (<= 600,000 vs >600,000 IU/mL; OR, 1.4; P = .0223). These factors plus previous treatment and response were overall predictors of SVR. Safety was similar among fibrosis groups. Conclusions: Peginterferon alfa-2b plus weight-based ribavirin is effective and safe in patients who failed interferon alfa/ribavirin therapy. Genotype, baseline viral load, and fibrosis stage were predictors of response.
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Twenty-nine HCV-infected patients were treated with pegylated interferon alpha. Diagnosis was based on serum HCV RNA-PCR positive results and liver biopsy. All patients had elevated serum levels of alanine aminotransferase at the time of the study, but liver disease was compensated. Patients were evaluated at baseline treatment and after 4 and 12 weeks of antiviral treatment with the Medical Outcomes Study 36-item Short-Form Health Survey. The Mini-International Neuropsychiatric Interview was used to exclude previous or current psychiatric diagnoses. Both patients and psychiatrists were blind to the HCV RNA status, and serum HCV RNA test results only became available after the visit at week 12. After antiviral treatment, 16 patients (55.2%) were classified as nonresponders and 13 (44.8%) were classified as responders. When compared to nonresponders, responders had a greater improvement in the HRQOL scores for the mental health domain (P<.019). Differences in other domains were not significant. The present study confirms that active viral infection is one possible reason for the poor Health-Related Quality of Life in this population.
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Objective - We aimed to identify the clinical and genetic [IL23 receptor (IL23R) single nucleotide polymorphisms (SNPs)] predictors of response to therapy in patients with ulcerative colitis. Patients and methods - A total of 174 patients with ulcerative colitis, 99 women and 75 men, were included. The mean age of the patients was 47±15 years and the mean disease duration was 11±9 years. The number of patients classified as responders (R) or nonresponders (NR) to several therapies was as follows: 110 R and 53 NR to mesalazine (5-ASA), 28 R and 20 NR to azathioprine (AZT), 18 R and 7 NR to infliximab. Clinical and demographic variables were recorded. A total of four SNPs were studied: IL23R G1142A, C2370A, G43045A, and G9T. Genotyping was performed by real-time PCR using Taqman probes. Results - Older patients were more prone to respond to 5-ASA (P=0.004), whereas those with pancolitis were less likely to respond to such therapies (P=0.002). Patients with extraintestinal manifestations (EIMs) were less likely to respond to 5-ASA (P=0.001), AZT (P=0.03), and corticosteroids (P=0.06). Carriers of the mutant allele for IL23R SNPs had a significantly higher probability of developing EIMs (P<0.05), a higher probability of being refractory to 5-ASA (P<0.03), but a higher likelihood of responding to AZT (P=0.05). A significant synergism was observed between IL23R C2370A and EIMs with respect to nonresponse to 5-ASA (P=0.03). Conclusion - Besides extent of disease and age at disease onset, the presence of EIMs may be a marker of refractoriness to 5-ASA, corticosteroids, and AZT. IL23R SNPs are associated both with EIMs and with nonresponse to 5-ASA and corticosteroids.
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INTRODUCTION: It is known that the hepatitis B (HB) vaccine is effective, but it is alarming that sudden drops of antibody levels may coincide with the onset of adolescence. METHODS: Antibody levels against HB vaccine surface antigen (anti-HBs) and HB vaccine core antigen (anti-HBc) were measured on the blood samples of children with a mean age of 11.4 years. RESULTS: About 54.8% had protective levels of anti-HBs. Of those who were anti-HBc-positive (4.4%), an average of 218.4 anti-HBs mIU/mL was found. CONCLUSIONS: Immunological protection was found in the majority of children. However, more studies are needed to elucidate the heritability of nonresponders and establish strategies against such events.