2,889 research outputs found
Microsatellite instability and defects in mismatch repair proteins: a new aetiology for Sertoli cell‐only syndrome
Microsatellite instability is characteristic of certain types of cancer, and is present in rodents lacking specific DNA mismatch repair proteins. These azoospermic mice exhibit spermatogenic defects similar to some human testicular failure patients. Therefore, we hypothesized that microsatellite instability due to deficiencies in mismatch repair genes might be an unrecognized aetiology of human testicular failure. Because these azoospermic patients are candidates for testicular sperm extraction and ICSI, transmission of mismatch repair defects to the offspring is possible. Seven microsatellite loci were analysed for instability in specimens from 41 testicular failure patients and 20 controls. Blood and testicular DNA were extracted from patient and control specimens, and amplified by PCR targeting seven microsatellite loci. DNA fragment length was analysed with an ABI Prism 310 Genotyping Machine and GeneScan software. Immunohistochemistry was performed on paraffinized testis biopsy sections and cultured testicular fibroblasts from each patient to determine if expression of the mismatch repair proteins hMSH2 and hMLH1 was normal in both somatic and germline cells. Results demonstrate that microsatellite instability and DNA mismatch repair protein defects are present in some azoospermic men, predominantly in Sertoli cell‐only patients (P < 0.01 and P < 0.05 respectively). This provides evidence of a previously unrecognized aetiology of testicular failure that may be associated with cancer predispositio
Valsartan for attenuating disease evolution in early sarcomeric hypertrophic cardiomyopathy: the design of the Valsartan for Attenuating Disease Evolution in Early Sarcomeric Hypertrophic Cardiomyopathy (VANISH) trial
Background:
Hypertrophic cardiomyopathy (HCM) is often caused by sarcomere gene mutations, resulting in left ventricular hypertrophy (LVH), myocardial fibrosis, and increased risk of sudden cardiac death and heart failure. Studies in mouse models of sarcomeric HCM demonstrated that early treatment with an angiotensin receptor blocker (ARB) reduced development of LVH and fibrosis. In contrast, prior human studies using ARBs for HCM have targeted heterogeneous adult cohorts with well-established disease. The VANISH trial is testing the safety and feasibility of disease-modifying therapy with an ARB in genotyped HCM patients with early disease.
Methods:
A randomized, placebo-controlled, double-blind clinical trial is being conducted in sarcomere mutation carriers, 8 to 45 years old, with HCM and no/minimal symptoms, or those with early phenotypic manifestations but no LVH. Participants are randomly assigned to receive valsartan 80 to 320 mg daily (depending on age and weight) or placebo. The primary endpoint is a composite of 9 z-scores in domains representing myocardial injury/hemodynamic stress, cardiac morphology, and function. Total z-scores reflecting change from baseline to final visits will be compared between treatment groups. Secondary endpoints will assess the impact of treatment on mutation carriers without LVH, and analyze the influence of age, sex, and genotype.
Conclusions:
The VANISH trial is testing a new strategy of disease modification for treating sarcomere mutation carriers with early HCM, and those at risk for its development. In addition, further insight into disease mechanisms, response to therapy, and phenotypic evolution will be gained
Cardiac dysfunction in cancer survivors unmasked during exercise
Introduction: The cardiac dysfunction associated with anthracycline-based chemotherapy cancer treatment can exist sub-clinically for decades before overt presentation. Stress echocardiography, the measurement of left ventricular (LV) deformation and arterial haemodynamic evaluation have separately been used to identify sub-clinical cardiovascular (CV) dysfunction in several patient groups including those with hypertension and diabetes. The purpose of the present cross-sectional study was to determine whether the combination of these techniques could be used to improve the characterisation of sub-clinical CV dysfunction in long-term cancer survivors previously treated with anthracyclines. Materials and methods: Thirteen long-term cancer survivors (36±10 years) with prior anthracycline exposure (11±8 years post-treatment) and 13 age-matched controls were
recruited. Left ventricular structure, function and deformation were assessed using echocardiography. Augmentation index was used to quantify arterial haemodynamic load and was measured using applanation tonometry. Measurements were taken at rest and during two stages of low-intensity incremental cycling.Results: At rest, both groups had comparable global LV systolic, diastolic and arterial function (all P>0.05), however longitudinal deformation was significantly lower in cancer survivors (-18±2 v -20±2, P<0.05). During exercise this difference between groups persisted and further differences were uncovered with significantly lower apical circumferential deformation in the cancer survivors (-24±5 v -29±5, -29±5 v 35±8 for first and second stage of exercise respectively, both P<0.05). Conclusion: In contrast to resting echocardiography the measurement of LV deformation at rest and during exercise provides a more comprehensive characterisation of sub-clinical LV dysfunction. Larger studies are required to determine the clinical relevance of these preliminary findings
Anthracycline-Induced Cardiotoxicity: Cardiac Monitoring by Continuous Wave-Doppler Ultrasound Cardiac Output Monitoring and Correlation to Echocardiography
Background: Anthracyclines are agents with a well-known cardiotoxicity. The study sought to evaluate the hemodynamic response to an anthracycline using real-time continuous-wave (CW)-Doppler ultrasound cardiac output monitoring (USCOM) and echocardiography in combination with serum biomarkers. Methods: 50 patients (26 male, 24 female, median age 59 years) suffering from various types of cancer received an anthracycline-based regimen. Patients' responses were measured at different time points (T0 prior to infusion, T1 6 h post infusion, T2 after 1 day, T3 after 7 days, and T4 after 3 months) with CW-Doppler ultrasound (T0-T4) and echocardiography (T1, T4) for hemodynamic parameters such as stroke volume (SV; SVUSCOM ml) and ejection fraction (EF; EFechocardiography%) and with NT-pro-BNP and hs-Troponin T (T0-T4). Results: During the 3-month observation period, the relative decrease in the EF determined by echocardiography was -2.1% (Delta T0-T4, T0 71 +/- 7.8%, T4 69.5 +/- 7%, p = 0.04), whereas the decrease in SV observed using CW-Doppler was -6.5% (Delta T0-T4, T0 54 +/- 19.2 ml, T4 50.5 +/- 20.6 ml, p = 0.14). The kinetics for serum biomarkers were inversely correlated. Conclusions: Combining real-time CW-Doppler USCOM and serum biomarkers is feasible for monitoring the immediate and chronic hemodynamic changes during an anthracycline-based regimen; the results obtained were comparable to those from echocardiography
Multi-Institutional Assessment of Adverse Health Outcomes Among North American Testicular Cancer Survivors After Modern Cisplatin-Based Chemotherapy
Purpose
To provide new information on adverse health outcomes (AHOs) in testicular cancer survivors (TCSs) after four cycles of etoposide and cisplatin (EPX4) or three or four cycles of bleomycin, etoposide, cisplatin (BEPX3/BEPX4).
Methods
Nine hundred fifty-two TCSs > 1 year postchemotherapy underwent physical examination and completed a questionnaire. Multinomial logistic regression estimated AHOs odds ratios (ORs) in relation to age, cumulative cisplatin and/or bleomycin dose, time since chemotherapy, sociodemographic factors, and health behaviors.
Results
Median age at evaluation was 37 years; median time since chemotherapy was 4.3 years. Chemotherapy consisted largely of BEPX3 (38.2%), EPX4 (30.9%), and BEPX4 (17.9%). None, one to two, three to four, or five or more AHOs were reported by 20.4%, 42.0%, 25.1%, and 12.5% of TCSs, respectively. Median number after EPX4 or BEPX3 was two (range, zero to nine and zero to 11, respectively; P > .05) and two (range, zero to 10) after BEPX4. When comparing individual AHOs for EPX4 versus BEPX3, Raynaud phenomenon (11.6% v 21.4%; P < .01), peripheral neuropathy (29.2% v 21.4%; P = .02), and obesity (25.5% v 33.0%; P = .04) differed. Larger cumulative bleomycin doses (OR, 1.44 per 90,000 IU) were significantly associated with five or more AHOs. Increasing age was a significant risk factor for one to two, three to four, or five or more AHOs versus zero AHOs (OR, 1.22, 1.50, and 1.87 per 5 years, respectively; P < .01); vigorous physical activity was protective (OR, 0.62, 0.51, and 0.41, respectively; P < .05). Significant risk factors for three to four and five or more AHOs included current (OR, 3.05 and 3.73) or former (OR, 1.61 and 1.76) smoking (P < .05). Self-reported health was excellent/very good in 59.9% of TCSs but decreased as AHOs increased (P < .001).
Conclusion
Numbers of AHOs after EPX4 or BEPX3 appear similar, with median follow-up of 4.3 years. A healthy lifestyle was associated with reduced number of AHOs
Why multidisciplinary clinics should be the standard for treating chronic kidney disease
In adults, strong evidence indicates that slowing progression of chronic kidney disease (CKD) requires an integrated, multidisciplinary approach. In children, however, this approach has not been studied. This editorial commentary to the study by Ajarmeh et al in this volume of Pediatric Nephrology highlights how a dedicated, multidisciplinary team of physicians, nurses, pharmacists, dieticians, social workders and clinic data managers slowed the progression of CKD in children to a remarkable degree. We discuss the strengths and limitations of the study and its cost implications, as well as the issue of determining the optional complement of physicians and allied health care professionals in such clinics. Our calculations indicate that the additional costs of such clinics would be recovered in one year, even if the progession of CKD were to be delayed by 1 year in only 2% of affected children. Here, we call on the international pediatric nephrology community to establihs guidelines for forming multidisciplinary clinics throughout the world. © IPNA 2012
B-type natriuretic peptide as a marker for cardiac dysfunction in anthracycline-treated children
Background Anthracyclines (AC) are useful antineoplastic agents, whose utility is limited by progressive cardiotoxicity. Our purpose was to evaluate plasma B-type natriuretic peptide (BNP), as a screening test for detecting late cardiac dysfunction in AC-treated children and to determine the prevalence of late cardiac dysfunction at low cumulative AC doses. Materials and Methods This was a prospective study in which patients who had completed AC therapy at least 1 year earlier, underwent a detailed echocardiogram and a simultaneous BNP level. Cardiac dysfunction was defined as any one of the following: shortening fraction (FS) 60 g·cm −2 , abnormal VCFc: ESWS ratio or decreased mitral inflow velocity (E/A) ratios, compared to age-specific norms. Results The cohort (n = 63) included 37 males with a median age of 13.1 years (range, 6.5–26.5 years). Cardiac dysfunction was found in 26 (41%) patients and in 40% of patients who received cumulative doses <150 mg·m −2 . ESWS was the most common abnormality. Mean BNP levels in the subset with abnormal function were significantly higher than the normal group (23.4 ± 25.3 vs. 14.2 ± 8.9 pg·ml −1 , P = 0.02). Conclusions Plasma BNP was significantly elevated in AC-treated patients with late cardiac dysfunction, although there was considerable overlap of levels between groups with and without cardiac dysfunction. BNP may need further evaluation as a serial index of cardiac function in this population. Cardiac dysfunction was observed in a significant proportion of patients, even at low cumulative AC doses. Pediatr Blood Cancer 2007;49:812–816. © 2006 Wiley-Liss, Inc.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/57395/1/21100_ftp.pd
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