Tonic firing rate controls dendritic Ca2+ signaling and synaptic gain in substantia nigra dopamine neurons

Author: Hage, T.A.; Khaliq, Z.M. Description: Substantia nigra dopamine neurons fire tonically resulting in action potential backpropagation and dendritic Ca(2+) influx. Using Ca(2+) imaging in acute mouse brain slices, we find a surprisingly steep relationship between tonic firing rate and dendritic Ca(2+). Increasing the tonic rate from 1 to 6 Hz generated Ca(2+) signals up to fivefold greater than predicted by linear summation of single spike-evoked Ca(2+)-transients. This “Ca(2+) supralinearity” was produced largely by depolarization of the interspike voltage leading to activation of subthreshold Ca(2+) channels and was present throughout…

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Attending to Threat: Race-based Patterns of Selective Attention

Author: Trawalter, S.; Todd, A.R.; Baird, A.A.; Richeson, J.A. Description: The present research investigated the extent to which the stereotype that young Black men are threatening and dangerous has become so robust and ingrained in the collective American unconscious that Black men now capture attention, much like evolved threats such as spiders and snakes. Specifically, using a dot-probe detection paradigm, White participants revealed biased attention toward Black faces relative to White faces (Study 1). Because the faces were presented only briefly (30-ms), the bias is thought to reflect the early…

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Story grammar ability in children with and without language disorder: story generation, story retelling, and story comprehension

Author: Merritt, D.D.; Liles, B.Z. Description: Twenty language-impaired and unimpaired children ages 9:0 to 11:4 participated in three story tasks. The children generated three original stories, retold two adventure stories, and then answered two sets of comprehension questions after each retelling. Stein and Glenn’s (1979) story grammar rules were adapted and used to analyze the narratives. The generated and retold stories produced by the language-disordered children contained fewer complete story episodes, a lower mean number of main and subordinate clauses per complete episode, and a lower frequency of use of…

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Epidemiology of drug resistance: implications for a post-antimicrobial era

Author: Cohen, M.L. Description: In the last several years, the frequency and spectrum of antimicrobial-resistant infections have increased in both the hospital and the community. Certain infections that are essentially untreatable have begun to occur as epidemics both in the developing world and in institutional settings in the United States. The increasing frequency of drug resistance has been attributed to combinations of microbial characteristics, selective pressures of antimicrobial use, and societal and technologic changes that enhance the transmission of drug-resistant organisms. Antimicrobial resistance is resulting in increased morbidity, mortality, and…

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Genetic and educational assortative mating among US adults

Author: Domingue, B.W.; Fletcher, J.; Conley, D.; Boardman, J.D. Description: Understanding the social and biological mechanisms that lead to homogamy (similar individuals marrying one another) has been a long-standing issue across many fields of scientific inquiry. Using a nationally representative sample of non-Hispanic white US adults from the Health and Retirement Study and information from 1.7 million single-nucleotide polymorphisms, we compare genetic similarity among married couples to noncoupled pairs in the population. We provide evidence for genetic assortative mating in this population but the strength of this association is substantially…

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Heat acclimation: phenotypic plasticity and cues to the underlying molecular mechanisms

Author: Horowitz, M. Description: Acclimation, in contrast to evolutionary adaptation, is a “within life time phenotypic adaptation” resulting in a widening of the dynamic regulatory range of body temperature. Increased efficiency and capacity of the thermoregulatory effectors, and delayed onset of the temperature threshold for thermal injury, contribute to the beneficial effects of acclimation. Reprogrammed gene expression and changes in cellular signaling underlie these responses. Constitutive elevation of the inducible heat shock protein (HSP) 72 kDa provides cytoprotection and delays thermal injury without the need for de novo HSP synthesis…

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Serotonin receptors: their key role in drugs to treat schizophrenia

Author: Meltzer, H.Y.; Li, Z.; Kaneda, Y.; Ichikawa, J. Description: Serotonin (5-HT)-receptor-based mechanisms have been postulated to play a critical role in the action of the new generation of antipsychotic drugs (APDs) that are usually referred to as atypical APDs because of their ability to achieve an antipsychotic effect with lower rates of extrapyramidal side effects (EPS) compared to first-generation APDs such as haloperidol. Specifically, it has been proposed by Meltzer et al. [J. Pharmacol. Exp. Ther. 251 (1989) 238] that potent 5-HT2A receptor antagonism together with weak dopamine (DA)…

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Preliminary attempts to fertilize human oocytes matured in vitro

Author: Edwards, R.G.; Donahue, R.P.; Baramki, T.A.; Jones, H.W.J. Description: Attempts were made to fertilize human oocytes after their maturation in culture. Initial attempts using washed spermatozoa showed that the great majority of eggs were unfertilized and that the spermatozoa failed to traverse the zona pellucida, probably because of lack of capacitation. Therefore, attempts were made to capacitate human spermatozoa by placing them in the reproductive tract of a rabbit, culturing them with pieces of human endosalpinx, taking them from cervical mucus, or transferring them with oocytes into the Fallopian…

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The Emerging Zika Pandemic: Enhancing Preparedness

Author: Lucey, D.R., & Gostin, L.O. Description: The Zika virus (ZIKV), a flavivirus related to yellow fever, dengue, West Nile, and Japanese encephalitis, originated in the Zika forest in Uganda and was discovered in a rhesus monkey in 1947. The disease now has explosive pandemic potential, with outbreaks in Africa, Southeast Asia, the Pacific Islands, and the Americas. Since Brazil reported Zika virus in May 2015, infections have occurred in at least 20 countries in the Americas. Puerto Rico reported the first locally transmitted infection in December 2015, but Zika…

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Comparison of Site of Death, Health Care Utilization, and Hospital Expenditures for Patients Dying With Cancer in 7 Developed Countries

Author: Bekelman, J.E.; Halpern, S.D.; Blankart, C.R.; Bynum, J.P.; Cohen, J.; Fowler, R.; Kaasa, S.; Kwietniewski, L.; Melberg, H.O.; Onwuteaka-Philipsen, B.; Oosterveld-Vlug, M.; Pring, A.; Schreyogg, J.; Ulrich, C.M.; Verne, J.; Wunsch, H.; Emanuel, E.J. Description: IMPORTANCE: Differences in utilization and costs of end-of-life care among developed countries are of considerable policy interest. OBJECTIVE: To compare site of death, health care utilization, and hospital expenditures in 7 countries: Belgium, Canada, England, Germany, the Netherlands, Norway, and the United States. DESIGN, SETTING, AND PARTICIPANTS: Retrospective cohort study using administrative and registry…

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