[Numerical expression of results].
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Humans↗
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[Numerical expression of results].
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Anesthesia↗
Updating reference values for placental weights in Northern Alberta.
OBJECTIVE: The purpose of this study was to establish normal parameters for placental weights and fetal/placental weight ratios. STUDY DESIGN: Placentas (2402) from uncomplicated singleton deliveries at the Royal Alexandra Hospital (Edmonton, Alberta) were collected from 1997 to 1998 and weighed after fixation. The nonparametric Mann-Whitney test was applied. RESULTS: New reference values were developed for fixed placental weights. Placentas at the 90th percentile were 50 to 100 g heavier than previously reported. Fetal/placental weight ratios at term were similar to published values. CONCLUSION: The new placental weight reference values from our institution represent a recent and local population. New values may partly reflect parallel increases in term birth weights.
Alberta↗
Metabolic syndrome in relation to structure and function of large arteries: a predominant effect of blood pressure. A report from the SU.VI.MAX. Vascular Study.
BACKGROUND: Metabolic syndrome (MetS) is associated with increased risk of cardiovascular disease. However, the contribution of MetS to intermediate cardiovascular endpoints such as structure and function alterations of large arteries is still unclear. METHODS: A total of 917 middle-aged French men and women participating to the SUpplémentation en VItamines et Minéraux AntioXydants (SU.VI.MAX) Vascular study were included. Carotid-femoral pulse wave velocity was used to assess aortic stiffness. Carotid ultrasound examination included measurements (at sites free of plaques) of intima-media thickness (IMT) at the common carotid arteries (CCA) and assessment of atherosclerotic plaques in the extracranial carotid arteries. RESULTS: Prevalence of the MetS defined by the National Cholesterol Education Program was 8.7%. Compared with subjects without MetS, subjects with MetS had significant higher mean values of CCA-IMT (P = .02) and pulse wave velocity (P = .0001). We found that MetS was not significantly related to the presence of carotid plaques. Blood pressure was the only MetS component associated with all vascular parameters. Addition of other MetS components in the multivariate models contributed poorly to the explained variance of these parameters. CONCLUSIONS: The MetS is adversely associated with markers of early arterial dysfunction, such as CCA-IMT and arterial stiffness. Although the associations between MetS and these arterial parameters are related to insulin resistance, blood pressure was shown to be the most important MetS component in relation to structure and function of large arteries.
Blood Pressure↗
[Abecedary of the "Annales". Part 9].
The terms included and detailed in the present part are: Standard error, Clinical trial, Randomized controlled trial, Cross-over clinical trial, Equivalence trial and non inferiority trial.
Cross-Over Studies↗
Circadian rhythm abnormalities in the acute phase of cerebral infarction correlate with poor prognosis in the chronic phase.
The aim of this study was to determine circadian rhythm abnormalities in patients with acute cerebral infarction and their relationship with prognosis in the chronic phase. The subjects were 50 patients who were admitted within 48 h of onset. Rectal temperature and wrist motor activity were recorded during the acute phase. Time-series data were assayed by MEM spectral analysis. Functional prognosis (degree of handicap) was assessed at 3 months after stroke onset by the modified Rankin Scale. Ambulatory patients tended to exhibit circadian rhythm in rectal temperature and/or wrist activity rhythms, whereas non-ambulatory patients did not (P < 0.001) in the acute phase of ischemic stroke. Our findings suggest the biological rhythms of rectal temperature and wrist activity during the acute stroke phase might be a possible prognostic indicator of their chronic phase.
Aged↗
Assessing new interventions in women's health.
One of the most frequent clichés in evidence-based medicine (EBM) is that 'without evidence there can be no evidence-based practice'. How best to assemble evidence on the effectiveness (or ineffectiveness) of a treatment is central to the entire concept of EBM. Particularly in women's health, where even small or moderate improvements in the individual well-being of one woman can lead to an enormous impact on the overall health of the nation, it is important to be able to detect or refute reliably small to moderate treatment effects. Evidence must come from studies where biases and random errors have been minimised, which requires large scale randomised controlled trials, the methodology of which is relatively familiar. However, the challenges peculiar to running trials in women's health have been less fully considered. This article draws on examples from the literature to illustrate many of the principles that need to be considered when running, or assessing, a trial of an intervention in women's health.
Bias↗
Preserved and impaired aspects of predictive grip force control in cerebellar patients.
OBJECTIVE: To analyze preserved and impaired aspects of feedforward grip force control during cyclic arm movements with a hand-held object after cerebellar damage. METHODS: We tested eight subjects with unilateral or bilateral cerebellar pathologies and eight healthy control subjects. Participants performed cyclic vertical arm movements with a hand held instrumented object at three different speeds. RESULTS: Compared to controls, patients excerted increased grip forces. The minimum force ratio between grip force and load force was constant across all movement frequencies, suggesting that patients anticipated speed-related changes in load magnitudes by adjusting the grip force. Thus the scaling of grip force level to self-generated load magnitudes was preserved. The coupling between grip and load profiles was assessed by cross correlation analysis. Patients exhibited significantly decreased maximum coefficients of cross correlation implicating impaired anticipation of inertial load fluctuations. However feedforward control could be preserved, as obvious from zero time lags of the maximum cross correlation coefficient. CONCLUSIONS: Our findings suggest that cerebellar lesions affect the processing of predictive grip force modulation in anticipation of inertial loads. Our results add further evidence to the theoretical concept that the cerebellum implements internal feedforward models. However, preserved functions may indicate compensatory mechanisms or extra-cerebellar aspects of grip and load force regulation. SIGNIFICANCE: The observed dissociation of performance deficits may have direct clinical implication and may guide the development of individual therapeutic strategies for patients with cerebellar disorders.
Adult↗
Correlation between blood flow velocity in the middle cerebral artery and EEG during cognitive effort.
Cognitive effort modifies blood flow velocity (BFV) in the middle cerebral artery (MCA) which can be recorded by transcranial Doppler sonography (TCD). EEG parameters can be used as indicators of cortical activation. To find temporal and spatial relation between circulatory and bioelectric phenomena, we used combined EEG and TCD measurements during cognitive experiments. Bilateral BFV in the MCAs and 16-channel scalp EEG were recorded during mental arithmetic (MA) and verbal fluency (VF) tests in 12 healthy volunteers. Temporal profile of BFV, heart rate (HR), EEG central frequency (CF), relative alpha power (ralphap), and laterality index (Li) for BFV and CF were statistically analysed. During mental effort, BFV changes showed a reproducible pattern, which was different in MA and VF tests. The Li(BFV) correlated with handedness in 9/12 subjects (75%) in the VF, and in 6/12 subjects (50%) in the MA test. Significant correlation was found between Li(BFV) and Li(CF) during VF (r(2) = 0.69). Li was more indicative for the hemispheric dominance in the VF than in the MA test. During VF test, correlation between HR and BFV was significant in 7/12 subjects. CF and ralphap provide real time assessment of the functional state of the brain tissue during cognition. The correlation between CF and BFV during mental activity suggests a short latency neurogenic and a long latency, supposedly chemical regulation of regional blood flow. Parallel analysis of EEG and flow parameters increases the confidence of determining hemispheric dominance and provides an alternative to study physiological consequences of cognitive processes.
Adult↗
The prognostic value of epidermal growth factor receptor is related to tumor differentiation and the overall treatment time of radiotherapy in squamous cell carcinomas of the head and neck.
Accelerated repopulation in head-and-neck carcinomas might be related to the expression of proliferative factors such as epidermal growth factor receptor (EGFr). The present study focuses on the prognostic value of EGFr for T-site control and the relation to tumor cell differentiation and overall treatment time. We studied 336 patients treated with primary radiotherapy using 66-68 Gy, 2 Gy per fraction and overall treatment times of 912, 612, or 512 weeks. Pretreatment biopsies were stained for EGFr.Thirty-five percent of the carcinomas had less than 50% of the area stained for EGFr. Small T-size and well-differentiated tumors was associated with a high degree of staining (p = 0.001 and p = 0.002, respectively). EGFr was of poor prognostic influence regarding local control in patients treated with 9 weeks split-course, whereas the opposite was found for patients given accelerated treatment in 5 weeks. A similar relationship between outcome, overall treatment time, and differentiation has previously been shown. The two parameters were analyzed together by separating the tumors with low EGFr and/or poor differentiation from tumors with well/moderate differentiation and high EGFr, resulting in odds ratios for T-site failure of 12 (1.43-104), 0.91 (0.51-1.65), and 0.43 (0.17-1.08), for treatment times of 912, 612, and 512 weeks, respectively. The tumor response to variations in fractionation is heterogeneous, and the prognostic impact of EGFr and differentiation might be relative and dependent on the overall treatment time of radiotherapy.
Carcinoma, Squamous Cell↗
Vascular complications associated with arteriotomy closure devices in patients undergoing percutaneous coronary procedures: a meta-analysis.
OBJECTIVES: This study was designed to assess the safety of arteriotomy closure devices (ACDs) versus mechanical compression by meta-analysis in patients undergoing percutaneous transfemoral coronary procedures. BACKGROUND: Although ACDs are widely applied for hemostasis after percutaneous endovascular procedures, their safety is controversial. METHODS: Randomized, case-control, and cohort studies comparing access-related complications using ACDs versus mechanical compression were analyzed. The primary end point was the cumulative incidence of vascular complications, including pseudoaneurysm, arteriovenous fistula, retroperitoneal hematoma, femoral artery thrombosis, surgical vascular repair, access site infection, and blood transfusion. RESULTS: A total of 30 studies involving 37,066 patients were identified. No difference in complication incidence between Angio-Seal and mechanical compression was revealed in the diagnostic (Dx) setting (odds ratio [OR] 1.08, 95% confidence interval [CI] 0.11 to 10.0) or percutaneous coronary interventions (PCI) (OR 0.86, 95% CI 0.65 to 1.12). Meta-analysis of randomized trials only showed a trend toward less complications using Angio-Seal in a PCI setting (OR 0.46, 95% CI 0.20 to 1.04; p = 0.062). No differences were observed regarding Perclose in either Dx (OR 1.51, 95% CI 0.24 to 9.47) or PCI (OR 1.21, 95% CI 0.94 to 1.54) setting. An increased risk in complication rates using VasoSeal in the PCI setting (OR 2.25, 95% CI 1.07 to 4.71) was found. The overall analysis favored mechanical compression over ACD (OR 1.34, 95% CI 1.01 to 1.79). CONCLUSIONS: In the setting of Dx angiography, the risk of access-site-related complications was similar for ACD compared with mechanical compression. In the setting of PCI, the rate of complications appeared higher with VasoSeal.
Angioplasty, Balloon, Coronary↗
Minimally important differences were estimated for the Functional Assessment of Cancer Therapy-Colorectal (FACT-C) instrument using a combination of distribution- and anchor-based approaches.
OBJECTIVE: To estimate minimally important differences (MIDs) on the Functional Assessment of Cancer Therapy-Colorectal (FACT-C) instrument using anchor- and distribution-based methods. STUDY DESIGN AND SETTING: Preliminary MIDs were generated for FACT-C scores based on published results for two samples (n = 60 and n = 63) from the FACT-C validation study. Preliminary MIDs were confirmed using data from a Phase II randomized controlled clinical trial (n = 104) and a population-based observational study (n = 568). MIDs were estimated for the colorectal cancer subscale (CCS); the FACT-C Trial Outcome Index (TOI-C), which is the sum of the CCS, physical well-being, and functional well-being subscales; and the FACT-C total score. Both cross-sectional and longitudinal analyses were used. RESULTS: MIDs were stable across the different patient samples. The recommended MIDs ranged from 2 to 3 points for the CCS, 4 to 6 points for the TOI-C, and 5 to 8 points for the FACT-C total score. CONCLUSIONS: MIDs can enhance the interpretability of FACT-C scores, and they can be used to provide a basis for sample size estimation and to determine clinical benefit in combination with other measures of efficacy. General guidelines for estimating MIDs for other FACT instruments are suggested.
Adult↗
Genetic contribution to variation in larval development time, adult size, and longevity of starved adults of Anopheles gambiae.
The variation in mosquito life-history traits such as adult size has been studied with respect to environmental factors, but the genetic contribution to such variation has received almost no consideration. Using a full-sib design of F1s produced by wild caught Anopheles gambiae (M molecular form) females, we estimated broad-sense heritability of larval developmental time, adult size (based on dry weight and wing length), and longevity of starved adults. These traits were correlated (at the phenotypic level) with each other in females and males (|r(p)|>0.5, P<0.001). Longevity of starved adults increased with adult size, and both traits (adult longevity and size) decreased with longer larval development. Genetic correlations were lower (|r(g)|>0.45, P<0.05) but provided consistent evidence against a trade off between adult size and larval development time predicting that a mosquito can develop faster into a smaller adult or be a larger adult by a longer development. Estimates of heritability of the three traits were moderate to high (range: 0.05-0.48) and statistically significant (P<0.05), indicating substantial genetic contribution to the phenotypic variation in these traits. These results suggest that adaptive differences are likely to be found in these traits between A. gambiae populations.
Animals↗
Autonoetic consciousness in Alzheimer's disease: neuropsychological and PET findings using an episodic learning and recognition task.
OBJECTIVE: This study aims to map in patients with mild Alzheimer's disease (AD) the correlations between resting-state brain glucose utilization measured by FDG-PET and scores reflecting autonoetic consciousness in an episodic learning and recognition task. METHODS: Autonoetic consciousness, that gives a subject the conscious feeling to mentally travelling back in time to relive an event, was assessed using the Remember/Know (R/K) paradigm. RESULTS: AD patients provided less R responses (reflecting autonoetic consciousness) and more K ones (indicating the involvement of noetic consciousness) than healthy controls. Correct recognitions associated with a R response correlated with the metabolism of frontal areas bilaterally whereas those associated with a K response mainly correlated with the metabolism of left parahippocampal gyrus and lateral temporal cortex. CONCLUSIONS: These data show that recollection is impaired in AD and recognition is more based on a feeling of familiarity than in controls. In addition, the findings of our correlative approach indicate that the impairment of episodic memory is mainly subserved by the dysfunction of frontal areas and of the hippocampal region.
Aged↗
Serum neurotrophins--a study on the time course and influencing factors in a large old age sample.
The neurotrophins nerve growth factor (NGF) and brain-derived neurotrophic factor (BDNF) are important mediators of brain and neuronal development, the maintenance of homeostatic conditions in the adult nervous system, and the complex interplay of central and peripheral physiological and pathophysiological factors. To date there are few studies examining blood concentrations of neurotrophic factors in large samples of healthy and diseased individuals and no published study specifically addresses peripheral BDNF and NGF levels in late life. Using improved highly sensitive and specific fluorometric two-site enzyme-linked immunosorbent assays we examined BDNF (n=465) and NGF (n=175) serum levels in a large cohort of elderly individuals (age range: 70-103 years). Neither BDNF nor NGF serum levels proved to be normally distributed, indicating that previously published studies with small sample sizes using parametric testing may be misleading. A significant correlation was found between BDNF and platelet count (r=0.344, p<0.01), age and BDNF protein (r=-0.101, p=0.029) and BDNF and NGF serum levels (r=0.152, p=0.04). No other major influencing factors were found including gender, depression, and dementia.
Age Factors↗
Age-dependent decline of neprilysin in Alzheimer's disease and normal brain: inverse correlation with A beta levels.
Brain deposition of amyloid-beta (A beta) is a pathological hallmark of Alzheimer disease (AD) but A beta is also detected in non-demented elderly individuals. Neprilysin has been shown to be an important enzyme to degrade A beta in brain. We investigated whether decreased neprilysin levels contributes to the accumulation of A beta in AD and in normal aging. No difference in neprilysin protein and mRNA levels were found between AD subjects and age-matched controls. Protein levels of neprilysin were reduced with age in the temporal and frontal cortex of AD and normal brain. A significant positive correlation between insoluble A beta 40 and A beta 42 with age was found in cortex of normal brain whereas in AD brain the correlation between age and A beta was weaker. Our findings of an inverse correlation between neprilysin and insoluble A beta levels in both groups suggest that neprilysin is involved in the clearance of A beta. The observed age-dependent decline in neprilysin may be related to the increased A beta levels during normal aging. The similar rate of decline in neprilysin with age may not be the major cause of the high levels of A beta associated with AD but is likely to be a trigger of AD pathology.
Aged↗
Cerebral perfusion changes in mesial temporal lobe epilepsy: SPM analysis of ictal and interictal SPECT.
We examined cerebral perfusion changes in mesial temporal lobe epilepsy (mTLE) by the statistical parametric mapping of brain single photon emission computed tomography (SPECT) images of 38 mTLE patients and 19 normal controls. Ictal and interictal SPECTs were compared with control SPECTs by independent t test, and ictal and interictal SPECTs by paired t test. We evaluated the number of heterotopic neurons in temporal lobe white matter, white matter changes of the anterior temporal lobe (WCAT) and ictal hyperperfusion of the temporal stem (IHTS). Left mTLE showed interictal hypoperfusion in the ipsilateral hippocampus, bilateral thalami, and paracentral lobules. Right mTLE showed hypoperfusion in bilateral hippocampi, contralateral insula, bilateral thalami, and paracentral lobules. Both mTLEs showed ictal hyperperfusion in bilateral temporal lobes with ipsilateral predominance, and in the anterior frontal white matter bilaterally. By paired t test, ictal hyperperfusion was found in the ipsilateral temporal lobe, temporal stem, hippocampus, thalamus, putamen, insula, and bilateral precentral gyri, whereas ictal hypoperfusion was found in bilateral frontal poles and middle frontal gyri. Fifteen patients showed WCAT and 19 showed IHTS, a weak correlation was observed between WCAT and IHTS (r = 0.377, P = 0.02). WCAT was found to correlate with an early seizure onset age. In 35 patients, heterotopic neurons were found in the white matter of the resected temporal lobe, but the number of heterotopic neurons did not correlate with WCAT or IHTS. In summary, the cerebral perfusion patterns of mTLE suggest interictal hypofunction and ictal activation of the cortico-thalamo-hippocampal-insular network and ictal hypoperfusion of the anterior frontal cortex.
Adolescent↗
How reliable are fMRI-EEG studies of epilepsy? A nonparametric approach to analysis validation and optimization.
Simultaneously acquired functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) data hold great promise for localizing the spatial source of epileptiform events detected in the EEG trace. Despite a number of studies applying this method, there has been no independent and systematic validation of the approach. The present study uses a nonparametric method to show that interictal discharges lead to a blood oxygen level dependent (BOLD) response that is significantly different to that obtained by examining random 'events'. We also use this approach to examine the optimization of analysis strategy for detecting these BOLD responses. Two patients with frequent epileptiform events and a healthy control were studied. The fMRI data for each patient were analyzed using a model derived from the timings of the epileptiform events detected on EEG during fMRI scanning. Twenty sets of random pseudoevents were used to generate a null distribution representing the level of chance correlation between the EEG events and fMRI data. The same pseudoevents were applied to control data. We demonstrate that it is possible to detect blood oxygen level-dependent (BOLD) changes related to interictal discharges with specific and independent knowledge about the reliability of this activation. Biologically generated events complicate the fMRI-EEG experiment. Our proposed validation examines whether identified events have an associated BOLD response beyond chance and allows optimization of analysis strategies. This is an important step beyond standard analysis. It informs clinical interpretation because it permits assessment of the reliability of the connection between interictal EEG events and the BOLD response to those events.
Analysis of Variance↗