35 resultados para two-term control


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Background: Neural structural abnormalities as well as cognitive difficulties in language processing have been described in children born very preterm (<32 weeks of gestational age and/or <1500 g birth weight). These findings raise the question how premature birth is related to neural language organisation and lateralisation. The aim of the study was to test the following hypotheses: a) VPT/VLBW and control children show different language organisation b) language organisation in VPT/VLBW children is more bilateral compared to language organisation in control children c) positive correlations between language performance measures and language lateralisation exist in VPT/VLBW children and controls. Method: Brain activity was measured during a phonologic detection task in 56 very preterm born children and 38 term born control children aged 7 to 12 years using functional Magnetic Resonance Imaging. General IQ, verbal IQ, verbal fluency and reading comprehension were assessed outside the scanner. Results: Language organisation and lateralisation did not differ in very preterm and control children in overall comparisons. However, in very preterm children lateralisation increased between the age of 7 to 12 years. This correlation was not found in control children. Language organisation in very preterm children was bilateral in young children and left-sided in old children, whereas language organisation in control children was left-sided in the young and old age group. Frontal lateralisation correlated with General IQ in controls, but no other correlations between lateralisation and verbal performance were found. Discussion: The results of this study suggest different developmental patterns of language processing in very preterm born and term born control children. While very preterm born children showed atypical language organisation and lateralisation in younger years, typical left-sided patterns were found at the age of 12 years.

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An imminent food crisis reinforces the need for novel strategies to increase crop yields worldwide. Effective control of pest insects should be part of such strategies, preferentially with reduced negative impact on the environment and optimal protection and utilization of existing biodiversity. Enhancing the presence and efficacy of native biological control agents could be one such strategy. Plant strengthener is a generic term for several commercially available compounds or mixtures of compounds that can be applied to cultivated plants in order to ‘boost their vigour, resilience and performance’. Studies into the consequences of boosting plant resistance against pests and diseases on plant volatiles have found a surprising and dramatic increase in the plants' attractiveness to parasitic wasps. Here, we summarize the results from these studies and present new results from assays that illustrate the great potential of two commercially available resistance elicitors. We argue that plant strengtheners may currently be the best option to enhance the attractiveness of cultivated plants to biological control agents. Other options, such as the genetic manipulation of the release of specific volatiles may offer future solutions, but in most systems, we still miss fundamental knowledge on which key attractants should be targeted for this approach.

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The levels of histone mRNA increase 35-fold as selectively detached mitotic CHO cells progress from mitosis through G1 and into S phase. Using an exogenous gene with a histone 3' end which is not sensitive to transcriptional or half-life regulation, we show that 3' processing is regulated as cells progress from G1 to S phase. The half-life of histone mRNA is similar in G1- and S-phase cells, as measured after inhibition of transcription by actinomycin D (dactinomycin) or indirectly after stabilization by the protein synthesis inhibitor cycloheximide. Taken together, these results suggest that the change in histone mRNA levels between G1- and S-phase cells must be due to an increase in the rate of biosynthesis, a combination of changes in transcription rate and processing efficiency. In G2 phase, there is a rapid 35-fold decrease in the histone mRNA concentration which our results suggest is due primarily to an altered stability of histone mRNA. These results are consistent with a model for cell cycle regulation of histone mRNA levels in which the effects on both RNA 3' processing and transcription, rather than alterations in mRNA stability, are the major mechanisms by which low histone mRNA levels are maintained during G1.

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BACKGROUND CONTEXT Several randomized controlled trials (RCTs) have compared patient outcomes of anterior (cervical) interbody fusion (AIF) with those of total disc arthroplasty (TDA). Because RCTs have known limitations with regard to their external validity, the comparative effectiveness of the two therapies in daily practice remains unknown. PURPOSE This study aimed to compare patient-reported outcomes after TDA versus AIF based on data from an international spine registry. STUDY DESIGN AND SETTING A retrospective analysis of registry data was carried out. PATIENT SAMPLE Inclusion criteria were degenerative disc or disc herniation of the cervical spine treated by single-level TDA or AIF, no previous surgery, and a Core Outcome Measures Index (COMI) completed at baseline and at least 3 months' follow-up. Overall, 987 patients were identified. OUTCOME MEASURES Neck and arm pain relief and COMI score improvement were the outcome measures. METHODS Three separate analyses were performed to compare TDA and AIF surgical outcomes: (1) mimicking an RCT setting, with admission criteria typical of those in published RCTs, a 1:1 matched analysis was carried out in 739 patients; (2) an analysis was performed on 248 patients outside the classic RCT spectrum, that is, with one or more typical RCT exclusion criteria; (3) a subgroup analysis of all patients with additional follow-up longer than 2 years (n=149). RESULTS Matching resulted in 190 pairs with an average follow-up of 17 months that had no residual significant differences for any patient characteristics. Small but statistically significant differences in outcome were observed in favor of TDA, which are potentially clinically relevant. Subgroup analyses of atypical patients and of patients with longer-term follow-up showed no significant differences in outcome between the treatments. CONCLUSIONS The results of this observational study were in accordance with those of the published RCTs, suggesting substantial pain reduction both after AIF and TDA, with slightly greater benefit after arthroplasty. The analysis of atypical patients suggested that, in patients outside the spectrum of clinical trials, both surgical interventions appeared to work to a similar extent to that shown for the cohort in the matched study. Also, in the longer-term perspective, both therapies resulted in similar benefits to the patients.