Search results for "Investigations"

Correlation between mutation rate and genome size in riboviruses: mutation rate of bacteriophage Qβ.

2013

Abstract Genome sizes and mutation rates covary across all domains of life. In unicellular organisms and DNA viruses, they show an inverse relationship known as Drake’s rule. However, it is still unclear whether a similar relationship exists between genome sizes and mutation rates in RNA genomes. Coronaviruses, the RNA viruses with the largest genomes (∼30 kb), encode a proofreading 3′ exonuclease that allows them to increase replication fidelity. However, it is unknown whether, conversely, the RNA viruses with the smallest genomes tend to show particularly high mutation rates. To test this, we measured the mutation rate of bacteriophage Qβ, a 4.2-kb levivirus. Amber reversion-based Luria–D…

Chemistry and bioactivity of natural products

2011

Treatment of embryonal tumors with multilayered rosettes with carboplatin/etoposide induction and high-dose chemotherapy within the prospective P-HIT…

2021

Abstract Background Embryonal tumors with multilayered rosettes (ETMR) are highly aggressive tumors occurring in early childhood. Published clinical data refer to retrospective, heterogeneously treated cohorts. Here, we describe the outcome of patients treated according to the prospective P-HIT trial and subsequent HIT2000-interim-registry. Patients and methods Age-stratified treatment included carboplatin/etoposide induction, tandem high-dose chemotherapy (“CARBO/ETO + HDCT”), and response-stratified radiotherapy. Patients with centrally reviewed neuropathological and molecularly confirmed diagnosis of ETMR recruited within the P-HIT trial (2001-2011; n = 19), the HIT2000-interim-registry …

Phase II study of irinotecan in combination with temozolomide (TEMIRI) in children with recurrent or refractory medulloblastoma: a joint ITCC and SIO…

2013

BackgroundThis multicenter phase II study investigated temozolomide + irinotecan (TEMIRI) treatment in children with relapsed or refractory medulloblastoma.MethodsPatients received temozolomide 100–125 mg/m2/day (days 1–5) and irinotecan 10 mg/m2/day (days 1–5 and 8–12) every 3 weeks. The primary endpoint was tumor response within the first 4 cycles confirmed ≥4 weeks and assessed by an external response review committee (ERRC). In a 2-stage Optimum Simon design, ≥6 responses in the first 15 evaluable patients were required within the first 4 cycles for continued enrollment; a total of 19 responses from the first 46 evaluable patients was considered successful.ResultsSixty-six patients were…

External investigations and disciplinary sanctions against auditors: the impact on audit quality

2015

In this paper, we provide empirical evidence for the impact of disciplinary sanctions imposed on Spanish auditing firms and their engagement partners. The disciplinary sanctions resulted from external investigations, which revealed misapplications of auditing standards. In particular, we evaluate (a) the efficacy of the external supervisory board in identifying low-quality auditors and (b) the effectiveness of the disciplinary system in improving the quality of subsequent statutory audits performed by the sanctioned auditors. We employ two earnings management indicators as proxies for audit quality: loss avoidance through extraordinary items and abnormal accruals. And we compare these measu…

Evolution of fitness in experimental populations of vesicular stomatitis virus

1996

Abstract The evolution of fitness in experimental clonal populations of vesicular stomatitis virus (VSV) has been compared under different genetic (fitness of initial clone) and demographic (population dynamics) regimes. In spite of the high genetic heterogeneity among replicates within experiments, there is a clear effect of population dynamics on the evolution of fitness. Those populations that went through strong periodic bottlenecks showed a decreased fitness in competition experiments with wild type. Conversely, mutant populations that were transferred under the dynamics of continuous population expansions increased their fitness when compared with the same wild type. The magnitude of …

Statistical properties of the site-frequency spectrum associated with lambda-coalescents.

2013

Abstract Statistical properties of the site-frequency spectrum associated with Λ-coalescents are our objects of study. In particular, we derive recursions for the expected value, variance, and covariance of the spectrum, extending earlier results of Fu (1995) for the classical Kingman coalescent. Estimating coalescent parameters introduced by certain Λ-coalescents for data sets too large for full-likelihood methods is our focus. The recursions for the expected values we obtain can be used to find the parameter values that give the best fit to the observed frequency spectrum. The expected values are also used to approximate the probability a (derived) mutation arises on a branch subtending a…

Twenty-year follow-up of children with obstructive sleep apnea.

2022

STUDY OBJECTIVES: Obstructive sleep apnea (OSA) in children is associated with acute metabolic, cardiovascular, and neurocognitive abnormalities. The long-term outcomes of childhood OSA into adulthood have not been established. We performed a 20-year follow-up of patients with polysomnography-documented OSA in childhood compared to a healthy control group to evaluate the long-term anthropometric, sleep, cognitive, and cardiovascular outcomes. METHODS: Children diagnosed with severe OSA between ages 1 and 17 years (mean, 4.87 ± 2.77) were prospectively contacted by telephone as young adults after approximately 20 years. Data collected included reported anthropometric information, educational…

Exploring the Relationship between Disease Awareness and Outcomes in Patients with Chronic Obstructive Pulmonary Disease

2020

<b><i>Background:</i></b> Disease awareness is a challenge in the management of chronic obstructive pulmonary disease (COPD). <b><i>Objectives:</i></b> The aim of this analysis was to explore the association between COPD optimal and suboptimal awareness, clinical parameters, and the following patient-reported outcomes: modified Medical Research Council (mMRC), Treatment Satisfaction Questionnaire (TSQM-9), COPD Assessment Test (CAT), Morisky Medication-Taking Adherence Scale (MMAS-4), and Brief Illness Perception Questionnaire (B-IPQ). <b><i>Methods:</i></b> This post hoc analysis of the SAT study included all enrolled …

Mild obstructive sleep apnea increases hypertension risk, challenging traditional severity classification

2020

STUDY OBJECTIVES: The association of mild obstructive sleep apnea (OSA) with important clinical outcomes remains unclear. We aimed to investigate the association between mild OSA and systemic arterial hypertension (SAH) in the European Sleep Apnea Database cohort. METHODS: In a multicenter sample of 4,732 participants, we analyzed the risk of mild OSA (subclassified into 2 groups: mild(AHI 5-<11/h) (apnea-hypopnea index [AHI], 5 to <11 events/h) and mild(AHI 11-<15/h) (AHI, ≥11 to <15 events/h) compared with nonapneic snorers for prevalent SAH after adjustment for relevant confounding factors including sex, age, smoking, obesity, daytime sleepiness, dyslipidemia, chronic obstructive pulmona…