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991.
Prediction of children's reading skills using behavioral, functional, and structural neuroimaging measures 总被引:1,自引:0,他引:1
Hoeft F Ueno T Reiss AL Meyler A Whitfield-Gabrieli S Glover GH Keller TA Kobayashi N Mazaika P Jo B Just MA Gabrieli JD 《Behavioral neuroscience》2007,121(3):602-613
The ability to decode letters into language sounds is essential for reading success, and accurate identification of children at high risk for decoding impairment is critical for reducing the frequency and severity of reading impairment. We examined the utility of behavioral (standardized tests), and functional and structural neuroimaging measures taken with children at the beginning of a school year for predicting their decoding ability at the end of that school year. Specific patterns of brain activation during phonological processing and morphology, as revealed by voxel-based morphometry (VBM) of gray and white matter densities, predicted later decoding ability. Further, a model combining behavioral and neuroimaging measures predicted decoding outcome significantly better than either behavioral or neuroimaging models alone. Results were validated using cross-validation methods. These findings suggest that neuroimaging methods may be useful in enhancing the early identification of children at risk for poor decoding and reading skills. 相似文献
992.
van den Burg EH Engelmann J Bacelo J Gómez L Grant K 《Journal of neurophysiology》2007,97(3):2373-2384
Anesthetics may induce specific changes that alter the balance of activity within neural networks. Here we describe the effects of the GABA(A) receptor potentiating anesthetic etomidate on sensory processing, studied in a cerebellum-like structure, the electrosensory lateral line lobe (ELL) of mormyrid fish, in vitro. Previous studies have shown that the ELL integrates sensory input and removes predictable features by comparing reafferent sensory signals with a descending electromotor command-driven corollary signal that arrives in part through parallel fiber synapses with the apical dendrites of GABAergic interneurons. These synapses show spike timing-dependent depression when presynaptic activation is associated with postsynaptic backpropagating dendritic action potentials. Under etomidate, almost all neurons become tonically hyperpolarized. The threshold for action potential initiation increased for both synaptic activation and direct intracellular depolarization. Synaptically evoked inhibitory postsynaptic potentials (IPSPs) were also strongly potentiated and prolonged. Current source density analysis showed that backpropagation of action potentials through the apical dendritic arborization in the molecular layer was reduced but could be restored by increasing stimulus strength. These effects of etomidate were blocked by bicuculline or picrotoxin. It is concluded that etomidate affects both tonic and phasic inhibitory conductances at GABA(A) receptors and that increased shunting inhibition at the level of the proximal dendrites also contributes to increasing the threshold for action potential backpropagation. When stimulus strength is sufficient to evoke backpropagation, repetitive association of synaptic excitation with postsynaptic action potential initiation still results in synaptic depression, showing that etomidate does not interfere with the molecular mechanism underlying plastic modulation. 相似文献
993.
Xia SJ Rajput P Strzelecki DM Barr FG 《Laboratory investigation; a journal of technical methods and pathology》2007,87(4):318-325
Alveolar rhabdomyosarcoma (ARMS) is associated with chromosomal translocations that generate PAX3-FKHR and PAX7-FKHR fusion oncoproteins. Based on studies demonstrating that high PAX3-FKHR expression causes growth suppression, the hypothesis is proposed that, during ARMS tumorigenesis, the translocations cause low oncoprotein expression and are followed by collaborating events that block growth suppression pathways and permit upregulation of oncoprotein expression. To investigate oncogenic function at low expression levels, PAX3-FKHR was introduced into NIH3T3 cells in the pBabe retroviral vector. Compared to high expression systems, PAX3-FKHR expression from pBabe was lower and did not suppress growth, but showed transforming activity in the soft agar assay. As a possible collaborating event, PAX3-FKHR paired box mutations were previously shown in high expression systems to reverse growth suppressive effects. In the low expression system, the paired box mutation enhanced transformation in soft agar and focus formation assays. Although these mutations are candidate collaborating events, sequencing of paired box regions in ARMS tumors did not identify mutations. Finally, genes from known genetic alterations in ARMS were introduced, alone or combined, into NIH3T3 cells with high PAX3-FKHR expression and did not rescue growth suppression. In summary, these studies provide a model for an event in ARMS tumorigenesis that enhances PAX3-FKHR oncogenicity and abrogates growth suppression, but do not demonstrate a known event occurring in ARMS tumors that fulfills these criteria. 相似文献
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Roberts DR Ricci R Funke FW Ramsey P Kelley W Carroll JS Ramsey D Borckardt JJ Johnson K George MS 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》2007,181(2):213-220
Temporary immobilization of the leg serves as a useful model for the brain’s adaptive responses to casting, long-term confinement
to bed rest and possibly to trauma. As part of a larger program using TMS to investigate changes associated with bed rest,
we sought to determine whether casting of the leg causes brain excitability changes measurable with TMS, and the time course
of resolution of these changes. In this study, eight adults wore a full leg cast for 10 days. TMS measures of motor cortex
excitability were gathered before the cast was placed, and then immediately after cast removal, and 24 and 48 h later. A control
group did not wear a cast and underwent the same TMS sessions. Significant excitability changes occurred and peaked at 24 h
post cast removal in the TMS experimental group but not the non-casted group. 相似文献
997.
Stacey E. Pizzino Samuel Hundessa Vinu Verghis Mark Griffin Jo Durham 《Conflict and health》2018,12(1):36
Background
The presence of landmines and explosive remnants of war (ERW) including unexploded ordnance (UXO) poses a serious public health risk for populations living in conflict-affected and contaminated areas. Current analysis, however, provides only a partial view of the burden. In this study, we examined the multivariable relationship between year of injury, activity at the time of the incident, case fatalities and casualty rates in order to provide decision-makers with a more fine-grained understanding of landmines and ERW injuries in the Lao PDR.Methods
Using data from a retrospective, national household survey, frequency tables, logistic and Poisson regressions were performed using STATA 13 to predict the case fatality and population-standardized incidence rates for ERW casualties.Results
The findings indicated that most casualties were male (86.75%), with the majority of incidents (74.7%) occurring during the conflict period (1964–1979). The odds of death for the conflict period was 1.5 times that of the post-conflict period (1980–2008). The highest odds of death during the conflict period was associated with big bombs (OR?=?1.38, 95% CI: 1.243–1.522, p <?0.01), and landmine injuries were more common during conflict compared to the post-conflict period (IRR?=?1.42, 95% CI: 1.368–1.477, p?<?0.01). Post conflict, cluster munitions had the highest incidence rate for death or injury (IRR?=?1.07, 95%CI: 1.006–1.143, p =?0.03). Scrap collection which is often the target of mine risk education and thought to be one of the main activities at time of injury had the second lowest incidence rate of the activities related to incident during post-conflict period.Conclusions
As the first study of this nature in Lao PDR, this research provides information essential for planning services and prevention. This study suggests more effort needs to be directed towards addressing the geographical regions and population subgroups experiencing increased casualty numbers and odds of death. Further research is required to improve the documentation and understanding of the health and socio-economic consequences of landmine and ERW injuries.998.
Jung Jae Jo Jun Hyun Jo SunJoo Kim Jae-Mok Lee Sangkyu Lee 《Archives of pharmacal research》2018,41(4):450-458
Cocktail substrates are useful in investigating drug–drug interactions (DDI) that can rapidly identify the cytochrome P450 (CYP) isoforms that interact with test drugs. In this study, we developed and validated five probe drugs for CYP1A, CYP2B, CYP2C, CYP2D, and CYP3A using LC–MS/MS to determine CYP activities in mice. The five probe substrates were caffeine (2 mg/kg), bupropion (30 mg/kg), omeprazole (4 mg/kg), dextromethorphan (40 mg/kg), and midazolam (2 mg/kg) for CYP1A, CYP2B, CYP2C, CYP2D, and CYP3A, respectively. The cocktail substrates were orally administered to male 5-week-old ICR mice over 0–240 min. The analytical method was validated; it showed high selectivity, linearity, and acceptable accuracy. We confirmed the lack of interaction of this cocktail in the control state (no effect of CYP inducer or inhibitor) and suggested AUCratio (metabolite/substrate) as a unit to evaluate DDI in vivo. In addition, the cocktail assay was applied for the determination of pharmacokinetic parameters against phenobarbital as a selective CYP2B inducer and ketoconazole as a strong CYP3A inhibitor. The concentration of cocktail substrates and the LC–MS/MS method were optimized. In conclusion, we developed a simultaneous and comprehensive analysis system for predicting potential DDI in mice. 相似文献
999.
Ryan N. Hansen An T. Pham Elaine A. Böing Belinda Lovelace George J. Wan Donna A. Thomas 《Current medical research and opinion》2018,34(9):1549-1555
Objective: To evaluate intravenous (IV) acetaminophen (APAP) vs oral APAP use as adjunctive analgesics in cholecystectomy patients by comparing associated hospital length of stay (LOS), hospital costs, opioid use, and rates of nausea/vomiting, respiratory depression, and bowel obstruction.Methods: We conducted a retrospective analysis of the Premier Database (January 2012 to September 2015) including cholecystectomy patients who received either IV APAP or oral APAP. Differences in LOS, hospitalization costs, mean daily morphine equivalent dose (MED), and potential opioid-related adverse events were estimated. Multivariable logistic regression was performed for the binary outcomes and instrumental variable regressions, using the quarterly rate of IV APAP use for all hospitalizations by hospital as the instrument in two-stage least squares regressions for continuous outcomes. Models were adjusted for patient demographics, clinical risk factors, and hospital characteristics.Results: Among 61,017 cholecystectomy patients, 31,133 (51%) received IV APAP. Subjects averaged 51 and 57 years of age, respectively, in the IV and oral APAP cohorts. In the adjusted models, IV APAP was associated with 0.42 days shorter LOS (95% CI?=?–0.58 to –0.27; p?.0001), $1,045 lower hospitalization costs (95% CI?=?–$1,521 to –$569; p?.0001), 2?mg lower average daily MED (95% CI?=?–3?mg to –0.9?mg; p?=?.0005), and lower rates of respiratory depression (odds ratio [OR]?=?0.89, 95% CI?=?0.82–0.97; p?=?.006), and nausea and vomiting (OR?=?0.86, 95% CI?=?0.86–0.86; p?.0001).Conclusions: In patients having cholecystectomy, the addition of IV APAP to perioperative pain management is associated with shorter LOS, lower costs, reduced opioid use, and less frequent nausea/vomiting and respiratory depression compared to oral APAP. These findings should be confirmed in a prospective study comparing IV and oral APAP. 相似文献
1000.
Derivation and Validation of a Clostridium difficile Infection Recurrence Prediction Rule in a National Cohort of Veterans 下载免费PDF全文