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991.
Ramon C Holmes M Freeman WJ Gratkowski M Eriksen KJ Haueisen J 《Epilepsy & behavior : E&B》2009,14(1):54-59
Our objective was to study changes in EEG time-domain power spectral density (PSDt) and localization of language areas during covert object naming tasks in human subjects with epilepsy. EEG data for subjects with epilepsy were acquired during the covert object naming tasks using a net of 256 electrodes. The trials required each subject to provide the names of common objects presented every 4 seconds on slides. Each trial comprised the 1.0 second before and 3.0 seconds after initial object presentation. PSDt values at baseline and during tasks were calculated in the theta, alpha, beta, low gamma, and high gamma bands. The spatial contour plots reveal that PSDt values during object naming were 10-20% higher than the baseline values for different bands. Language was lateralized to left frontal or temporal areas. In all cases, the Wada test disclosed language lateralization to the left hemisphere as well. 相似文献
992.
Cynthia L. Harden Jennifer Hopp Tricia Y. Ting Page B. Pennell Jacqueline A. French W. Allen Hauser Samuel Wiebe Gary S. Gronseth David Thurman Kimford J. Meador Barbara S. Koppel Peter W. Kaplan Julian N. Robinson Barry Gidal Collin A. Hovinga Andrew N. Wilner Blanca Vazquez Lewis Holmes Allan Krumholz Richard Finnell Claire Le Guen 《Epilepsia》2009,50(5):1229-1236
A committee assembled by the American Academy of Neurology (AAN) reassessed the evidence related to the care of women with epilepsy (WWE) during pregnancy, including the risk of pregnancy complications or other medical problems during pregnancy, change in seizure frequency, the risk of status epilepticus, and the rate of remaining seizure-free during pregnancy. The committee evaluated the available evidence according to a structured literature review and classification of relevant articles. For WWE who are taking antiepileptic drugs (AEDs), there is probably no substantially increased risk (>2 times expected) of cesarean delivery or late pregnancy bleeding, and probably no moderately increased risk (>1.5 times expected) of premature contractions or premature labor and delivery. There is possibly a substantially increased risk of premature contractions and premature labor and delivery during pregnancy for WWE who smoke. WWE should be counseled that seizure freedom for at least 9 months prior to pregnancy is probably associated with a high likelihood (84–92%) of remaining seizure-free during pregnancy. WWE who smoke should be counseled that they possibly have a substantially increased risk of premature contractions and premature labor and delivery. 相似文献
993.
Distinguishing mantle cell lymphoma (MCL), from low-grade B-cell lymphoma is important because MCL is clinically more aggressive and is treated differently. Though most MCL overexpress cyclinD1 (CCND1) and have a t(11;14)(q13;q32), MCL that are negative for CCND1 exist. Some have translocations involving cyclinD2 (CCND2) and either the immunoglobulin heavy chain or kappa light chain locus. We present a CD5-positive, CCND1-negative B-cell lymphoma with a novel translocation involving CCND2 and the immunoglobulin lambda (IGL) gene. A 64-year-old male underwent resection of a polypoid mass of the ileum. Histology showed atypical, medium-sized lymphoid cells positive for CD20, CD5, CD43, and CCND2 by immunohistochemistry, and negative for CCND1, CCND3, and p27. Fluorescence in situ hybridization was negative for CCND1 abnormalities, but demonstrated a CCND2/IGL fusion. Clinical workup revealed stage IV disease. Current diagnostic criteria are insufficient for subclassifying this case, highlighting the need for additional studies on CCND2-translocated B-cell lymphomas to guide therapy appropriately. 相似文献
994.
Research findings have revealed that gay circuit parties may be locations that are disproportionately responsible for the increasing rates of many STIs/HIV among gay/bisexual men. Theories have been put forth that this may be the case because circuit parties are locales of prevalent drug use and unsafe sex. To explore the relationship between these two phenomena, in-depth qualitative interviews were undertaken with 17 men who (1) have sex with other men, (2) attended gay circuit parties in Montréal, Canada, in 2007. These revealed that drugs (including alcohol) were used intentionally to engage in unsafe sex, and then to justify this behavior after the fact. This process we called boundary play. 相似文献
995.
Assem FL Holmes P Levy LS 《Journal of toxicology and environmental health. Part B, Critical reviews》2011,14(8):537-570
Manganese (Mn), a naturally occurring element present in many foodstuffs, is an essential trace element with many biological functions. In industry, inorganic Mn compounds have a range of different applications, although the majority of Mn is used to make alloys and steel. For the general population, the major source of exposure to Mn is dietary, although drinking water may constitute an additional source in some regions. However, in occupationally exposed humans, inhalation of Mn is likely to be an important additional route. In general, Mn and its inorganic compounds are considered to possess low mutagenic or carcinogenic potential compared with some heavy metals. In this review, an up-to-date analysis of the available published studies on the carcinogenic and genotoxic potential of inorganic Mn is provided (organic Mn compounds are not considered). The current literature indicates that Mn may be weakly mutagenic in vitro and possibly clastogenic in vivo, with unknown genotoxic effects in humans; the possible mechanisms underlying these effects are discussed. The experimental evidence on carcinogenicity (quantitative increase in incidence of thyroid tumors in mice but not rats) does not provide any clear evidence, while the available occupational and environmental epidemiological evidence is equivocal as to whether exposure to inorganic Mn is associated with a significant cancer risk. Hence, it is concluded that there is insufficient evidence to indicate that inorganic Mn exposure produces cancer in animals or humans. 相似文献
996.
Holmes AD Copland DA Silburn PA Chenery HJ 《The international journal of neuropsychopharmacology / official scientific journal of the Collegium Internationale Neuropsychopharmacologicum (CINP)》2011,14(7):877-885
Nicotinic mechanisms may play a role in the cognitive deficits of Parkinson's disease (PD). Recently, on a cognitively demanding strategy-based priming task, nicotine selectively affected controlled semantic processing in young adult non-smokers as reported by Holmes et al. (International Journal of Neuropsychopharmacology 11, 389-399, 2008). Such controlled semantic processing is compromised in PD. This study investigated the effects of acute transdermal nicotine on controlled semantic processing in non-smokers with PD (n = 10) and non-smoking matched controls (n = 16) using a strategy-based semantic priming paradigm. Transdermal nicotine patches (7 mg/24 h) were administered in a double-blind, placebo-controlled, crossover design. Participants were instructed to expect target words from specified semantic categories based on the primes, while unexpected targets were also presented. Priming conditions included those concurring with trained expectations (expected-related and expected-unrelated), those which did not (unexpected-related and unexpected-unrelated), and neutral-baseline conditions. Controls evidenced significant expectancy effects (i.e. reaction-time differences for expected vs. unexpected conditions) under both drug states. An expectancy effect was not evident for PD under placebo due to a lack of reaction-time slowing for unexpected conditions. However, under nicotine an expectancy effect was present for PD at a level comparable to controls. Overall the findings indicate that nicotine can improve impaired controlled semantic processing in PD possibly via enhanced expectancy or inhibitory mechanisms. 相似文献
997.
Daftarian P Chowdhury R Ames P Wei C King AD de Rivero Vaccari JP Dillon L Price J Leung H Ashlock B Mesri E Perez V Züchner S Reiser J Lemmon V Keane RW 《Hybridoma (2005)》2011,30(5):409-418
In vivo electroporation has become a gold standard method for DNA immunization. The method assists the DNA entry into cells, results in expression and the display of the native form of antigens to professional cells of the immune system, uses both arms of immune system, has a built-in adjuvant system, is relatively safe, and is cost-effective. However, there are challenges for achieving an optimized reproducible process for eliciting strong humoral responses and for the screening of specific immune responses, in particular, when the aim is to mount humoral responses or to generate monoclonal antibodies via hybridoma technology. Production of monoclonal antibodies demands generation of high numbers of primed B and CD4 T helper cells in lymphoid organs needed for the fusion that traditionally is achieved by a final intravenous antigen injection. The purified antigen is also needed for screening of hundreds of clones obtained upon fusion of splenocytes. Such challenges make DNA vaccination dependent on purified proteins. Here, we have optimized methods for in vivo electroporation, production, and use of cells expressing the antigen and an in-cell Western screening method. These methods resulted in (1) reproducibly mounting robust humoral responses against antigens with different cell localizations, and (2) the ability to screen for antigen eliminating a need for protein/antigen purification. This process includes optimized parameters for in vivo electroporation, the use of transfected cells for final boost, and mild fixation/permeabilization of cells for screening. Using this process, upon two vaccinations via in vivo electroporation (and final boost), monoclonal antibodies against nucleus and cytoplasmic and transmembrane proteins were achieved. 相似文献
998.
Gregory M. Fomovsky Jeffrey W. Holmes 《Journal of molecular and cellular cardiology》2010,48(3):490-496
Extracellular matrix (ECM) components play essential roles in development, remodeling, and signaling in the cardiovascular system. They are also important in determining the mechanics of blood vessels, valves, pericardium, and myocardium. The goal of this brief review is to summarize available information regarding the mechanical contributions of ECM in the myocardium. Fibrillar collagen, elastin, and proteoglycans all play crucial mechanical roles in many tissues in the body generally and in the cardiovascular system specifically. The myocardium contains all three components, but their mechanical contributions are relatively poorly understood. Most studies of ECM contributions to myocardial mechanics have focused on collagen, but quantitative prediction of mechanical properties of the myocardium, or changes in those properties with disease, from measured tissue structure is not yet possible. Circumstantial evidence suggests that the mechanics of cardiac elastin and proteoglycans merit further study. Work in other tissues used a combination of correlation, modification or digestion, and mathematical modeling to establish mechanical roles for specific ECM components; this work can provide guidance for new experiments and modeling studies in myocardium. 相似文献
999.
AM Holmes JA Rudd FD Tattersall Q Aziz PLR Andrews 《British journal of pharmacology》2009,157(6):865-880
Nausea and vomiting are among the most common symptoms encountered in medicine as either symptoms of disease or side effects of treatments. Developing novel anti-emetics and identifying emetic liability in novel chemical entities rely on models that can recreate the complexity of these multi-system reflexes. Animal models (especially the ferret and dog) are the current gold standard; however, the selection of appropriate models is still a matter of debate, especially when studying the subjective human sensation of nausea. Furthermore, these studies are associated with animal suffering. Here, following a recent workshop held to review the utility of animal models in nausea and vomiting research, we discuss the limitations of some of the current models in the context of basic research, anti-emetic development and emetic liability detection. We provide suggestions for how these limitations may be overcome using non-animal alternatives, including greater use of human volunteers, in silico and in vitro techniques and lower organisms. 相似文献
1000.
A Biomarker Validation Study of Prenatal Chlorpyrifos Exposure within an Inner-City Cohort during Pregnancy
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Robin M. Whyatt Robin Garfinkel Lori A. Hoepner Howard Andrews Darrell Holmes Megan K. Williams Andria Reyes Diurka Diaz Frederica P. Perera David E. Camann Dana B. Barr 《Environmental health perspectives》2009,117(4):559-567