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Maternal smoking is associated with a host of negative health outcomes, including an increased risk of children developing attention-deficit/hyperactivity disorder (ADHD). This study evaluated the efficacy of health messages disseminated through Facebook Ads focused on reducing tobacco smoke exposure during pregnancy. Two message versions were promoted via post advertisements on Facebook—a static infographic and a video containing an animated version of the infographic. The reach of and engagement with each message version was evaluated. Comments made to the posts were assessed using content analysis. The infographic reached approximately 60,000 people and the video reached about 16,000 people. The average costs were $10.00 and $40.00 per 1,000 people reached for the infographic- and video-based posts, respectively. While there was no engagement with the video, the infographic was liked (n = 157), given alternative likes (n = 59), shared (n = 171 to 341), and commented on (n = 221). About one-quarter of comments contained a personal narrative and mentions of health history related to ADHD and/or smoking. Comments were more often negative (than positive) (16.6% vs 3.9%) and expressed skepticism more often than message acceptance (21.5% vs 12.2%). Facebook users were more responsive to the infographic (compared to the video) and static posts were a preferred channel (i.e., higher engagement at a lower cost) to disseminate messages when using the boost post feature on Facebook for health education. Our review of the comments provided insights into message acceptance and guidance for future social media-based health message campaigns. However, it is not known whether and if so, how, these findings on message exposure would correlate with behavioral intentions or changes in behavior, such as intentions to quit smoking or smoking cessation.

Climate change is widely known to affect plant phenology, but little is known about how these impacts manifest in the widespread sagebrush ecosystem of the Western United States, which supports a number of wildlife species of concern. Shifts in plant phenology can trigger consequences for the plants themselves as well as the communities of consumers that depend upon them. We assembled historical observations of first-flowering dates for 51 species collected in the 1970s and 1980s in a montane sagebrush community in the Greater Yellowstone Ecosystem and compared these to contemporary phenological observations targeting the same species and locations (2016-2019). We also assembled regional climate data (average spring temperature, day of spring snowmelt, and growing degree days) and tested the relationship between first-flowering time and these variables for each species. We observed the largest change in phenology in early-spring flowers, which, as a group, bloomed on average 17 days earlier, and as much as 36 days earlier, in the contemporary data set. Mid-summer flowers bloomed on average 10 days earlier, nonnative species 15 days earlier, and berry-producing shrubs 5 days earlier, while late summer flowering plants did not shift. The greatest correlates of early-spring and mid-summer flowering were average spring temperature and day of snowmelt, which was 21 days earlier, on average, in 2016-2019 relative to the 1973-1978 observations. The shifts in flowering phenology that we observed could indicate developing asynchronies or novel synchronies of these plant resources and wildlife species of conservation concern, including Greater Sage-grouse, whose nesting success is tied to availability of spring forbs; grizzly bears, which rely heavily on berries for their fall diet; and pollinators. This underscores the importance of maintaining a diverse portfolio of native plants in terms of species composition, genetics, phenological responsiveness to climatic cues, and ecological importance to key wildlife and pollinator species. Redundancy within ecological niches may also be important considering that species roles in the community may shift as climate change affects them differently. These considerations are particularly relevant to restoration and habitat-enhancement projects in sagebrush communities across western North America.

The current study reports on the efficacy of a multi-faceted motivationally designed undergraduate enrichment summer program for supporting science, technology, engineering and math (STEM) persistence. Structural equation modeling was used to compare summer program participants (n = 186), who participated in the program between their first and second years in college, to a propensity score matched comparison sample (n = 401). Participation in the summer program positively predicted science motivation (self-efficacy, task value), assessed eight months after the end of the program (second year in college). The summer enrichment program was also beneficial for science persistence variables, as evidenced by significant direct and indirect effects of the program on science course completion during students’ third year of college and students’ intentions to pursue a science research career assessed during the third year of college. In general, the program was equally beneficial for all participants, but ancillary analyses indicated added benefits with respect to task value for students with relatively lower prior science achievement during the first year of college and with respect to subsequent science course taking for males. Implications for developing effective interventions to reduce the flow of individuals out of STEM fields and for translating motivational theory into practice are discussed.

Despite efforts to attract and maintain diverse students in the science, technology, engineering and math (STEM) pipeline, issues with attrition from undergraduate STEM majors persist. The aim of this study was to examine how undergraduate science students' competence beliefs, task values, and perceived costs in science combine into motivational profiles and to consider how such profiles relate to short and long-term persistence outcomes in STEM. We also examined the relations between underrepresented group membership and profile membership. Using latent profile analysis, we identified three profiles that characterized 600 participants' motivation during their first semester in college: Moderate All, Very High Competence/Values-Low Effort Cost, and High Competence/Values-Moderate Low Costs. The Moderate All profile was associated with the completion of fewer STEM courses and lower STEM GPAs relative to the other profiles after one year and after four years of college. Furthermore, underrepresented minority students were overrepresented in the Moderate All profile. Findings contribute to our understanding of how science competence beliefs, task values, and perceived costs may coexist and what combinations of these variables may be adaptive or deleterious for STEM persistence and achievement.

The spread of waterpipe tobacco use among youth may be due in part to perceptions that waterpipe tobacco use is safer than other tobacco products, such as cigarettes. In two pilot studies, we sought to modify college waterpipe smokers' perceived risks and worry about waterpipe tobacco smoking.We conducted two web-based studies that varied whether college waterpipe users received information on (a) spread of and use of flavored tobacco in waterpipe and (b) harms of waterpipe smoking. Study 1 (N = 91) tested the "incremental" effects on perceptions of risk and worry of adding information about harms of waterpipe smoking to information on the spread of waterpipe and use of flavorings in the tobacco. Study 2 (N = 112) tested the effects on perceptions of risk and worry of reviewing information about harms of waterpipe smoking compared to a no information control group. In Study 1 only, we assessed as part of a 6-month follow-up (n = 70) the percentage of participants who reported no longer using waterpipe.Pooling data from both studies, participants who received information about the harms of waterpipe smoking reported greater perceived risk and worry about harm and addiction and expressed a stronger desire to quit. In Study 1, 62% of participants in the experimental group versus 33% in the control group reported having stopped waterpipe use.These are the first studies to show that perceptions of addiction and harm from waterpipe use can be modified using minimally intensive interventions; such interventions show promise at decreasing waterpipe use.

We have shown that diazepam (DZ) protects hippocampal neurons when administered early after transient cerebral ischemia. To examine mechanisms of DZ action, in the absence of systemic effects, we used an in vitro model of ischemia [oxygen-glucose deprivation (OGD)] in the adult hippocampal slice. We are interested in determining if DZ can prevent upstream events such as loss of ionic homeostasis and its consequences on neuronal transmission. We measured the effect of OGD on changes in intracellular Cl− and Ca2+. Application of DZ after OGD prevented the increase in intracellular Cl− in area CA1 pyramidal neurons, measured by optical imaging with the Cl− sensitive fluorescent probe, MEQ. The increase in intracellular Cl− after OGD led to a reduction in GABA responses 2 h later, measured in the presence of the GABA agonist, muscimol. When DZ was added for 1 h after OGD, muscimol responses were restored completely. To measure changes in intracellular Ca2+ after OGD, we bath-loaded adult hippocampal slices with calcium green-1 AM. OGD increased intracellular Ca2+ in CA1 pyramidal neurons. The addition of DZ prior to OGD reduced the increase in intracellular Ca2+ by approximately 50%. To determine the effect of DZ on neuronal transmission within the hippocampus, we measured field responses in area CA1 pyramidal neurons. Area CA1 population spikes were suppressed by OGD and they did not recover 1 h later. When DZ was included in the reoxygenation buffer for only 30 min, it restored the population spike amplitude to within 85% of that in normal slices. Thus, after OGD, DZ restores ionic homeostasis, preserves GABA responses and restores neuronal activity within the hippocampus. Acknowledgements: Supported by NIH grant #NS28791.

Persuading teen smokers to volunteer for smoking-cessation programs is a challenging yet understudied problem. As a method of dealing with this problem, we used and tested a foot-in-the-door (FITD) approach. Teen smokers were intercepted at malls and were assigned randomly to request compliance with a small behavior request of either (a) answering a few questions (light FITD) or (b) answering the same questions and a few additional ones, plus watching a short video about the effects of nicotine (heavy FITD). Participants were then called back by telephone several weeks later and asked to comply with a large behavior request of joining a cessation program that involved the use of self-help materials and telephone counseling. Although no differences were found in responses from the light and heavy groups, consent to enter the program was obtained from 12% of the pooled qualified intercepts and their parents (for those under 18 years). This recruitment rate was considered good, given that this is one of the only reported studies that recruited teen smokers from the general population to cessation programs.

Cosmetic dentistry has evolved with the advent of more robust porcelain materials and ever-stronger bonding agents. This series of three articles aims to provide a practical overview of what is now possible both functionally and cosmetically from the preparation of a small number of teeth, through a whole smile, to full mouth rehabilitation. A complete diagnosis is the starting point to planning any cosmetic or functional changes. Guidance is given on the techniques used but adequate training must be considered essential before embarking upon modification in occlusal schemes or even minor adjustments in smile design. Porcelain laminate veneers have a role in the restoration and rehabilitation of a wearing and functionally compromised dentition.

Cosmetic dentistry has evolved with the advent of more robust porcelain materials and ever-stronger bonding agents. This series of three articles aims to provide a practical overview of what is now possible both functionally and cosmetically from the preparation of a small number of teeth, through a whole smile, to full mouth rehabilitation. A complete diagnosis is the starting point to planning any cosmetic or functional changes. Guidance is given on the techniques used but adequate training must be considered essential before embarking upon modification in occlusal schemes or even minor adjustments in smile design. Conservative use of porcelain laminate veneers can result in significant aesthetic improvements to a patient's smile and it is not always necessary to prepare all the teeth visible in a smile.

Transient cerebral ischemia kills CA1 pyramidal cells of the hippocampus, whereas most CA1 interneurons survive. It has been proposed that calcium-binding proteins, neurotrophins, and/or inhibitory neuropeptides protect interneurons from ischemia. However, different synaptic responses early after reperfusion could also underlie the relative vulnerabilities to ischemia of pyramidal cells and interneurons. In this study, we used gramicidin perforated patch recording in ex vivo slices to investigate γ-aminobutyric acid (GABA) synaptic function in CA1 pyramidal cells and interneurons 4 h after a bilateral carotid occlusion accompanied by hypovolemic hypotension. At this survival time, the amplitudes of both miniature inhibitory postsynaptic currents (mIPSCs) and GABA-evoked currents were reduced in CA1 pyramidal cells, but not in CA1 interneurons. In addition, the mean rise time of mIPSCs was reduced in pyramidal cells. The reversal potential for the GABA current ( EGABA) did not shift toward depolarizing values in either cell type, indicating that the driving force for chloride was unchanged at this survival time. We conclude that early during reperfusion GABAergic neurotransmission is attenuated exclusively in pyramidal neurons. This is likely explained by reduced GABAA receptor sensitivity or clustering and possibly also reduced GABA release, rather than by an elevation of intracellular chloride. Impaired GABA function may contribute to ischemic neuronal death by enhancing the excitability of CA1 pyramidal cells and facilitating N-methyl-d-aspartic acid channel opening. Therefore, normalizing GABAergic function might be a useful pharmacological approach to counter excessive, and potentially excitotoxic, glutamatergic activity during the postischemic period.

Most smokers have some conflicting thoughts and feelings about their smoking; that is, they feel ambivalent. Whether felt ambivalence can be adequately measured and then used to predict the desire to quit among teen smokers has yet to be explored. Hence, among 402 teen smokers involved in a smoking cessation intervention, we first examined the psychometric properties of an eight-item ambivalence scale via exploratory and confirmatory analyses. After excluding one item, the scale was internally consistent and formed a single factor. We also report on whether felt ambivalence towards smoking assessed at baseline and at four and eight months post-baseline was related to the desire to quit in cross-sectional and prospective analyses. In all cross-sectional and prospective analyses, smokers who felt increasingly ambivalent reported a stronger desire to quit. These results suggest that ambivalence might be a useful construct to explore further and experimentally induce to assess its effects on desire to quit.

Background Airway allergen challenge studies have shown the upregulation of cytokines in local airway tissues and distal effects on bone marrow precursors for eosinophils and basophils. Objective We investigated whether local intranasal allergen challenge alters the phenotype of circulating basophils to a primed state. Methods Ten subjects with allergic rhinitis were challenged with allergen by means of intranasal spray on 3 sequential days. Basophils were isolated from subjects before challenge and 3, 24, and 96 hours after the third allergen challenge. Basophils were compared before challenge and after the last allergen challenge for levels of FceRIβ protein by means of Western blotting and for FceRIβ mRNA expression by means of real-time PCR. Basophils were also compared with regard to spontaneous secretion of IL-4 and IL-13. Results Basophil FceRIβ protein levels increased in 5 of 6 subjects after allergen challenge relative to before challenge. Likewise, basophil FceRIβ mRNA levels increased a median of 2-fold after the last challenge relative to before challenge ( P =.007, n=9). IL-13 protein was detected in supernatants of 7 of 9 subjects' basophil-enriched cultures after the last challenge compared with 3 of 9 basophil-enriched cultures before challenge (median, 6.2 vs 0 pg/mL; P =.058). IL-4 was not detected in any culture supernatant. Conclusion Intranasal allergen challenge transiently activates circulating basophils by increasing expression of the FceRIβ subunit and spontaneous IL-13 secretion. Because FceRIβ is an amplifier of FceRI-mediated responses and IL-13 is proinflammatory, these findings support a primed basophil functional state and demonstrate a systemic effect of local allergen challenge that could contribute in exacerbating allergic reactions.

Ischemic injury to the CNS results in loss of ionic homeostasis and the development of neuronal death. An increase in intracellular Ca2+is well established, but there are few studies of changes in intracellular Cl–([Cl–]i) after ischemia. We used anin vitromodel of cerebral ischemia (oxygen–glucose deprivation) to examine changes in [Cl–]iand GABAAreceptor-mediated responses in hippocampal slices from adult rats. Changes in [Cl–]iwere measured in area CA1 pyramidal neurons using optical imaging of 6-methoxy-N-ethylquinolinium chloride, a Cl–-sensitive fluorescent indicator. Oxygen–glucose deprivation induced an immediate rise in [Cl–]i, which recovered within 20 min. A second and more prolonged rise in [Cl–]ioccurred within the next hour, during which postsynaptic field potentials failed to recover. The sustained increase in [Cl–]iwas not blocked by GABAAreceptor antagonists. However, oxygen–glucose deprivation caused a progressive downregulation of the K+–Cl–cotransporter (KCC2), which may have contributed to the Cl–accumulation. The rise in [Cl–]iwas accompanied by an inability of the GABAAagonist muscimol to cause Cl–influx.In vivo, diazepam is neuroprotective when given early after ischemia, although the mechanism by which this occurs is not well understood. Here, we added diazepam early after oxygen–glucose deprivation and prevented the downregulation of KCC2 and the accumulation of [Cl–]i. Consequently, both GABAAresponses and synaptic transmission within the hippocampus were restored. Thus, after oxygen–glucose deprivation, diazepam may decrease neuronal excitability, thereby reducing the energy demands of the neuron. This may prevent the activation of downstream cell death mechanisms and restore Cl–homeostasis and neuronal function.

During transient cerebral ischemia, there is a temporary and robust accumulation of extracellular GABA in the hippocampus. We examined whether the acute exposure of GABA A / benzodiazepine receptors to high concentrations of GABA early after ischemia results in receptor down-regulation as observed in vitro. Gerbils were killed 30 and 60 min following a 5-min bilateral carotid occlusion, and their brains were prepared for receptor autoradiography. The hydrophilic GABA A receptor antagonist [ 3 H]SR-95531 and the hydrophobic benzodiazepine agonist [ 3 H]flunitrazepam were used to distinguish between cell surface and internalized receptors. Ischemia significantly decreased [ 3 H]SR-95531 binding in hippocampal areas CA1 and CA3 and in the dentate gyrus 30 min after ischemia. Scatchard analysis in area CA1 revealed that ischemia decreased the B max as low as 44%. The affinity of the remaining sites was increased substantially (72% decrease in K D ). As expected, there were no changes in the binding of [ 3 H]flunitrazepam to hippocampus in the early postischemic period because the benzodiazepine could bind to both internalized receptors and those on the cell surface. We hypothesize that prolonged exposure (∼30-45 min) of GABA A receptors to high concentrations of synaptic GABA in vivo causes receptor down-regulation, perhaps via receptor internalization.

The effects of glutamatergic excitotoxins on intracellular Cl- were investigated in the CA1 pyramidal cell layer of the hippocampal slice. Hippocampal slices from rats (14-19 days old) were loaded with 6-methoxy-N-ethylquinolinium chloride (MEQ), a Cl(-)-sensitive fluorescent probe with a fluorescence intensity that correlates inversely with intracellular [Cl-]. Slices were exposed for at least 10 min at 26-28 degrees C to N-methyl-D-aspartate (NMDA; 100 microM) or alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA; 50 microM). A UV laser scanning confocal microscope was used to measure changes in MEQ fluorescence within area CA1 pyramidal cell soma. Both glutamate receptor agonists produced a rapid decrease in MEQ fluorescence that persisted after washout following a 10-min exposure. The effects of NMDA and AMPA were prevented by the competitive antagonists 2-amino-5-phosphonopentanoic acid and 6,7-dinitroquinoxaline-2,3-dione, respectively. Neither tetrodotoxin nor picrotoxin prevented the effect of NMDA or AMPA, indicating the lack of involvement of presynaptic mechanisms. The effects of NMDA and AMPA on MEQ fluorescence were dependent on the levels of extracellular Cl-, but only NMDA responses were dependent on the levels of extracellular Na+. Removal of Ca2+ from the superfusion medium did not alter the effects of NMDA or AMPA on MEQ fluorescence. In addition, neither the Ca2+ ionophore ionomycin nor the L-type voltage-gated Ca2+ channel agonist (Bay K 8644) decreased MEQ fluorescence. The effects of NMDA and AMPA on cell (somal) volume were also assessed with the fluorescent probe calcein acetoxymethyl ester. Both NMDA and AMPA decreased calcein fluorescence (indicating an increased cell volume), but this was preceded by the decrease in MEQ fluorescence (equivalent to an intracellular accumulation of approximately 20 mM Cl-). Thus, excitotoxins may cause Cl- influx via an anion channel other than the GABA(A) receptor and/or reduce Cl- efflux mechanisms to produce cell swelling. Such anionic shifts may promote neuronal excitability and cell death following an excitotoxic insult to the hippocampal slice.

We determined if changes in intraneuronal Cl- occur early after ischemia in the hippocampal slice. Slices from juvenile rats (14-19 days old) were loaded with the cell-permeant form of 6-methoxy-N-ethylquinolinium chloride (MEQ), a Cl(-)-sensitive fluorescent dye. Real-time changes in intracellular chloride concentration ([Cl-]i) were measured with UV laser scanning confocal microscopy in multiple neurons within each slice. In vitro ischemia (26-28 degrees C, 10 min) was confirmed by the loss of synaptic transmission (evoked field excitatory postsynaptic potentials) from pyramidal cells in area CA1. After ischemia and reoxygenation (10 min), MEQ fluorescence decreased significantly in CA1 pyramidal cells and interneurons. The decreased fluorescence corresponded to an ischemia-induced increase in [Cl-]i of approximately 10 mM. Pretreatment with the GABA(A)-gated Cl- channel antagonist picrotoxin (100 microM) blocked the ischemia-induced change in [Cl-]i. Analysis of the superfusates indicated that ischemia also caused a transient amino acid (GABA, glutamate, and aspartate) release that was maximal at approximately 10 min, returning to baseline shortly thereafter. Recovery from ischemia was confirmed by the return of synaptic transmission in area CA1, the return toward baseline of the ischemia-induced decrease in MEQ fluorescence, and exclusion of propidium iodide from MEQ fluorescent cells. Furthermore, pyramidal cells did not undergo cell swelling during this early phase of reoxygenation, as indicated by the volume-sensitive dye calcein. Thus, mild ischemia induces the accumulation of [Cl-]i secondary to GABA(A) receptor activation, in the absence of cellular swelling or death. In contrast, depolarization of the slice with K+ (50 mM) decreased MEQ fluorescence significantly but caused cell swelling. Picrotoxin did not prevent the K+-induced increase in [Cl-]i. It is possible that an increased [Cl-]i, following either an ischemic event or an episode of depolarization, would reduce the Cl- driving force and thereby limit synaptic transmission by GABA. To support this hypothesis, ischemia caused a reduction in the ability of the GABA agonist muscimol to increase [Cl-]i after 20-min reoxygenation.

Benzodiazepines protect hippocampal neurons when administered within the first few hours after transient cerebral ischemia. Here, we examined the ability of diazepam to prevent early signals of cell injury (before cell death) after in vitro ischemia. Ischemia in vitro or in vivo causes a rapid depletion of ATP and the generation of cell death signals, such as the release of cytochrome c from mitochondria. Hippocampal slices from adult rats were subjected to 7 min of oxygen-glucose deprivation (OGD) and assessed histologically 3 h after reoxygenation. At this time, area CA1 neurons appeared viable, although slight abnormalities in structure were evident. Immediately following OGD, ATP levels in hippocampus were decreased by 70%, and they recovered partially over the next 3 h of reoxygenation. When diazepam was included in the reoxygenation buffer, ATP levels recovered completely by 3 h after OGD. The effects of diazepam were blocked by picrotoxin, indicating that the protection was mediated by an influx of Cl(-) through the GABA(A) receptor. It is interesting that the benzodiazepine antagonist flumazenil did not prevent the action of diazepam, as has been shown in other studies using the hippocampus. Two hours after OGD, the partial recovery of ATP levels occurred simultaneously with an increase of cytochrome c (approximately 400%) in the cytosol. When diazepam was included in the reoxygenation buffer, it completely prevented the increase in cytosolic cytochrome c. Thus, complete recovery of ATP and prevention of cytochrome c release from mitochondria can be achieved when diazepam is given after the loss of ATP induced by OGD.

INTRODUCTION Many young smokers underestimate their risk for becoming addicted to cigarettes. We explored whether informing light college smokers (i.e., fewer than 5 cigarettes/day) of their genetic predisposition to nicotine dependence influenced their perceived risks and worry about becoming addicted, their ability to quit (i.e., self-efficacy), their desire to quit, and smoking cessation. METHODS College smokers (n = 142) received educational materials on mechanisms and consequences of nicotine addiction and were offered genetic susceptibility testing for nicotine dependence. Participants who accepted testing were randomized to receive feedback or no feedback (i.e., control). Tested participants learned they were above or not above average genetic risk for nicotine dependence. All participants responded to questions about perceived risks and worry about becoming addicted, efficacy to quit, and desire to quit. Cessation was assessed during a 1-month follow-up. RESULTS Efficacy beliefs, worry about becoming addicted, and desire to quit did not differ by study condition or feedback. Perceived risk for becoming addicted was highest among tested participants informed they were above average risk for nicotine dependence. Overall, self-reported 30- but not 7-day quit rate was higher among participants who underwent genetic testing compared with control participants. CONCLUSIONS This pilot study is the first to show that among light college smokers, receipt of genetic susceptibility feedback to nicotine dependence potentially curbs smoking without producing detrimental effects.

We developed the Alcohol Pharmacology Education Partnership (APEP), a set of modules designed to integrate a topic of interest (alcohol) with concepts in chemistry and biology for high school students. Chemistry and biology teachers (n = 156) were recruited nationally to field-test APEP in a controlled study. Teachers obtained professional development either at a conference-based workshop (NSTA or NCSTA) or via distance learning to learn how to incorporate the APEP modules into their teaching. They field-tested the modules in their classes during the following year. Teacher knowledge of chemistry and biology concepts increased significantly following professional development, and was maintained for at least a year. Their students (n = 14 014) demonstrated significantly higher scores when assessed for knowledge of both basic and advanced chemistry and biology concepts compared to students not using APEP modules in their classes the previous year. Higher scores were achieved as the number of modules used increased. These findings are consistent with our previous studies, demonstrating higher scores in chemistry and biology after students use modules that integrate topics interesting to them, such as drugs (the Pharmacology Education Partnership).

In this review, we present evidence for the role of gamma-aminobutyric acid (GABA) neurotransmission in cerebral ischemia-induced neuronal death. While glutamate neurotransmission has received widespread attention in this area of study, relatively few investigators have focused on the ischemia-induced alterations in inhibitory neurotransmission. We present a review of the effects of cerebral ischemia on pre and postsynaptic targets within the GABAergic synapse. Both in vitro and in vivo models of ischemia have been used to measure changes in GABA synthesis, release, reuptake, GABA(A) receptor expression and activity. Cellular events generated by ischemia that have been shown to alter GABA neurotransmission include changes in the Cl(-) gradient, reduction in ATP, increase in intracellular Ca(2+), generation of reactive oxygen species, and accumulation of arachidonic acid and eicosanoids. Neuroprotective strategies to increase GABA neurotransmission target both sides of the synapse as well, by preventing GABA reuptake and metabolism and increasing GABA(A) receptor activity with agonists and allosteric modulators. Some of these strategies are quite efficacious in animal models of cerebral ischemia, with sedation as the only unwanted side-effect. Based on promising animal data, clinical trials with GABAergic drugs are in progress for specific types of stroke. This review attempts to provide an understanding of the mechanisms by which GABA neurotransmission is sensitive to cerebral ischemia. Furthermore, we discuss how dysfunction of GABA neurotransmission may contribute to neuronal death and how neuronal death can be prevented by GABAergic drugs.

The accumulation of reactive oxygen species (ROS) in the brain is associated with several neurodegenerative conditions. ROS can affect ionic homeostasis leading to impaired neurotransmission. Here, we determined the ability of H2O2, a membrane permeant ROS, to alter intraneuronal Cl−, an important regulator of neuronal excitability. Real-time alterations in intracellular chloride, [Cl−]i, were measured with UV laser scanning confocal microscopy in hippocampal slices loaded with the cell-permeant form of 6-methoxy-N-ethylquinolium iodide (MEQ), a Cl−-sensitive fluorescent probe. In slices superfused with H2O2for 10 min, there was a significant decrease in MEQ fluorescence (elevation in [Cl−]i) in area CA1 pyramidal cell soma but not in interneurons located in stratum radiatum. Alterations in [Cl−]i induced by H2O2were prevented by the iron chelator deferoxamine and the vitamin E analog Trolox, suggesting the involvement of free radicals. The influx of Cl−probably occurred through the GABA-gated Cl−channel because the effects of H2O2were blocked by picrotoxin. In addition, HPLC analysis of the superfusates indicated that GABA and glutamate accumulated extracellularly after H2O2exposure. Excitatory amino acid receptor antagonists 2-amino-5-phoshopentanoic acid and 1,2,3,4-tetrahydro-6-nitro-2, 3-dioxo-benzo[f]quinoxaline-7-sulfonamide also attenuated the effect of H2O2on MEQ fluorescence. The changes in [Cl−]i induced by H2O2were Ca2+-dependent and Na+-independent. After exposure of slices to H2O2, the ability of the GABA agonist muscimol to increase [Cl−]i was attenuated. Thus, ROS, like H2O2, may impair transmembrane Cl−gradients and reduce inhibitory neurotransmission, further promoting neuronal damage in oxidative stress-related disease and in aging.

This study describes the pharmacological properties of GABAA receptors expressed in P19-N cells using fluorescence imaging of intracellular chloride with 6-methoxy-N-ethylquinolinium iodide (MEQ). We show that application of the GABA agonist, muscimol (10-200 microM), produces time- and concentration-dependent increases in intracellular [Cl-] that are blocked by bicuculline. Diazepam (10 microM) and pentobarbital (1 mM) potentiate muscimol-stimulation. These receptors exhibit novel pharmacological properties. The neurosteroid, 3alpha-hydroxy-5alpha-pregnane-20-one (1-10 microM) exhibited weak potency in enhancement of muscimol-stimulation. Ethanol (50 and 100 mM) exhibited high efficacy on muscimol responses, a 4- to 5-fold potentiation, respectively, of muscimol (10 microM) alone. GABA and muscimol allosterically modulated specific binding of [3H]flunitrazepam to differentiated P19 cells. Modulation of GABAA receptor mediated increases in intracellular [Cl-] demonstrated stability in response magnitude from 7 to 15 days following removal of retinoic acid. In concert, GABAA receptor subunit mRNA and protein expression patterns in these neuron-like cells were stable over the same period. Using RT-PCR we determined that differentiated P19 cells lack gamma1, gamma2L, alpha6 and delta subunit mRNAs while expressing alpha1, alpha2, alpha3, alpha4, alpha5, beta1, beta2, beta3, gamma2S and gamma3. Furthermore, subunit specific antibody immunocytochemical labeling of cells with a neuronal morphology indicated the presence of alpha1, alpha2, alpha4, and gamma2 subunits (the only subunits tested). Therefore, P19-N cells should prove useful to researchers in need of a model cell culture system in which to study function and regulation of neuronal GABAA receptors.

Arthur Jacobs (1899-1974) was the father of urology in Glasgow. His extensive experience with genitourinary tuberculosis, ureterosigmoidostomy, and bladder augmentation were far ahead of his time. He became an expert in retropubic prostatectomy and was a pioneer in early imaging techniques.

Following transient cerebral ischemia, pyramidal cells within area CA1 of the hippocampus exhibit delayed neuronal death. While interneurons within this sector continue to survive long-term, there is evidence that some interneurons in area CA1 are vulnerable to damage. To determine the nature of vulnerability in a neurochemically heterogeneous population of interneurons throughout area CA1, we examined the labeling of gamma-aminobutyric acid (GABA)ergic interneurons with an antibody to the GABAA receptor alpha 1-subunit 1-35 days following cerebral ischemia in the Mongolian gerbil. Unlike some other GABA interneuron markers, this antibody labels both the dendrites and soma of interneurons, allowing dendritic structure to be examined. Three to four days following ischemia, the pyramidal cells in area CA1 had degenerated, and the alpha 1-subunit-positive interneurons in all layers of area CA1 had developed severely beaded dendrites. At longer survival times (21-35 days), the alpha 1-subunit-immunolabeled dendrites of these interneurons had a fragmented appearance. In contrast, interneurons bordering str. oriens and alveus typically exhibited normal dendritic morphology. Despite the pathologic changes, there was no evidence of interneuron loss in area CA1 up to 35 days post-ischemia. Normal interneuron morphology was also observed in area CA3 and dentate gyrus, regions where neither pyramidal neurons nor granule cells, respectively, die following 5 min of cerebral ischemia. To determine if the ischemia-induced changes in interneuron morphology could be prevented, diazepam was administered 30 and 90 min following ischemia. Diazepam produces long-term neuroprotection of area CA1 pyramidal neurons. In gerbils sacrificed 35 days after ischemia, diazepam markedly attenuated the dendritic beading of the area CA1 interneurons. In addition, the dendrites did not display the fragmented labeling by the alpha 1-subunit antibody. Thus, despite their long-term survival, CA1 hippocampal interneurons in the gerbil can express severe structural abnormalities after transient cerebral ischemia coincident with pyramidal cell degeneration, and the injury to the dendrites can be prevented by the neuroprotectant diazepam.

The ability of diazepam, a benzodiazepine full agonist, and imidazenil, a benzodiazepine partial agonist, to protect hippocampal area CA1 neurons from death for at least 35 days after cerebral ischemia was investigated. Diazepam (10 mg/kg) administered to gerbils 30 and 90 minutes after forebrain ischemia produced significant protection of hippocampal area CA1 pyramidal neurons 7 days later. In gerbils surviving for 35 days, diazepam produced the same degree of neuroprotection (70% +/- 30%) in the hippocampus compared with 7 days after ischemia. The therapeutic window for diazepam was short; there was no significant neuroprotection when the administration of diazepam was delayed to 4 hours after ischemia. The neuroprotective dose of diazepam also produced hypothermia (approximately 32 degrees C) for several hours after injection. To assess the role of hypothermia in neuroprotection by diazepam, hypothermia depth and duration was simulated using a cold-water spray in separate gerbils. Seven days after ischemia, neuroprotection by hypothermia was similar to that produced by diazepam. However, 35 days after ischemia, there was no significant protection by hypothermia, suggesting that hypothermia does not play a significant role in long-term diazepam neuroprotection. Imidazenil (3 mg/kg), which produced only minimal hypothermia, protected area CA1 of hippocampus to the same degree as that by diazepam 7 days after ischemia. At 35 days after ischemia, significant protection remained, but it was considerably reduced compared with 7 days. Like diazepam, the therapeutic window for imidazenil was short. Imidazenil neuroprotection was lost when the drug was administered as early as 2 hours after ischemia. The ability of ischemia to produce deficits in working memory and of benzodiazepines to prevent the deficits also was investigated. Gerbils trained on an eight-arm radial maze before ischemia demonstrated a significant increase in the number of working errors 1 month after ischemia. The ischemia-induced deficits in working memory were completely prevented by diazepam but not by imidazenil. There was a significant, but weak, negative correlation between the degree of CA1 pyramidal cell survival and the number of working errors in both the diazepam and imidazenil groups. Thus, if given early enough during reperfusion, both benzodiazepine full and partial agonists are neuroprotective for at least 35 days, but the lack of sedating side effects of imidazenil must be weighed against its reduced efficacy.

The septo-hippocampal pathway contains a major gamma-aminobutyric acid (GABA) projection to dendritic fields within the hippocampus. To determine the importance of the septo-hippocampal pathway in ischemia-induced accumulation of GABA and subsequent cell death in area CA1 of hippocampus, septo-hippocampal deafferentation of adult gerbils was performed. Electrolytic lesions were produced in the medial or medial plus lateral septal regions in gerbils 7 days prior to being subjected to 5 min forebrain ischemia. The extent of deafferentation of the dorsal hippocampus was determined histochemically by acetylcholinesterase staining. Both the medial and medial plus lateral septal lesions produced nearly complete loss of acetylcholinesterase staining in the dorsal hippocampus indicating relatively complete deafferentation. During and following ischemia, in vivo microdialysis was used to measure extracellular GABA accumulation, which reached concentrations up to 1060 +/- 143% of basal. Septo-hippocampal deafferentation in both groups of lesioned animals failed to prevent the accumulation of GABA (and glutamate) induced by ischemia, indicating that ischemia-induced GABA accumulation in area CA1 arises principally from intrinsic GABAergic interneurons. Ischemic animals with medial septal lesions did not demonstrate neuroprotection or increased damage in the stratum pyramidale 7 days after reperfusion. Since the septo-hippocampal pathway provides the source of GABAergic disinhibition within the hippocampus, neither disinhibition nor the septo-hippocampal input appear to play an important role in the development of ischemia-induced neuronal death in the hippocampus.

Editor's Note: In 2003, the Society for Neuroscience initiated the Science Educator Award to recognize an outstanding neuroscientist who has made significant contributions to the education of the public ( ). The first recipient was Eric

Waterpipe tobacco smoking is increasing in the United States among college students. Through a web-based survey, we explored associations among factual and perceived knowledge, perceived risks and worry about harm and addiction, and desire to quit among 316 college waterpipe tobacco smoking users. Overall, factual knowledge of the harm of waterpipe tobacco smoking was poor, factual and perceived knowledge was weakly correlated, both forms of knowledge were related inconsistently to perceived risks and worry, and neither form of knowledge was associated with the desire to quit. Findings provide preliminary insights as to why knowledge gaps may not predict cessation among waterpipe users.

Although scanning probe microscopy is traditionally limited to slow temporal response, techniques utilizing nonlinear tip-to-sample interactions can be used to capture very fast temporal signals (voltages, in our case). Such SPM-based techniques may deliver unrivaled spatial and temporal resolution. We have developed a scanning force microscope probe for measuring ultrafast voltage signals with picosecond time resolution. Measurements of VLSI and MMIC devices are shown.

Scanning force microscopy has been developed as a practical, non-contact probing technique for measuring voltage waveforms at internal nodes of integrated devices and circuits. Dynamic voltage contrast is achieved with high spatial and temporal resolution. The factors contributing to system bandwidth, voltage sensitivity and spatial resolution are discussed. Time-domain and frequency-domain measurements of silicon and gallium arsenide circuits are presented.

Quantitative autoradiographic techniques were used to compare the distribution of GABAA, GABAB, and glycine receptors in the subcortical auditory pathway of the big brown bat, Eptesicus fuscus. For GABAA receptors, the ligand used was 35S-t-butylbicyclophosphorothionate (TBPS) for GABAB receptors, 3H-GABA was used as a ligand in the presence of isoguvacine to block binding to GABAA sites; for glycine, the ligand used was 3H-strychnine. In the subcortical auditory nuclei there appears to be at least a partial complementarity in the distribution of GABAA receptors labeled with 35S-TBPS and glycine receptors labeled with 3H-strychnine, GABAA receptors were concentrated mainly in the inferior colliculus (IC) and medial geniculate nucleus, whereas glycine receptors were concentrated mainly in nuclei below the level of the IC. Within the IC, there was a graded spatial distribution of 35S-TBPS binding; the most dense labeling was in the dorsomedial region, but very sparse labeling was observed in the ventrolateral region. There was also a graded spatial distribution of 3H-strychnine binding. The most dense labeling was in the ventral and lateral regions and the weakest labeling was in the dorsomedial region. Thus, in the IC, the distribution of 35S-TBPS was complementary to that of 3H-strychnine. GABAB receptors were distributed at a low level throughout the subcortical auditory nuclei, but were most prominent in the dorsomedial part of the IC.

(B6 X A)F1 mice were immunized with sperm whale myoglobin, and T cell clones and hybridomas were generated. Hybridoma 74a.e9 was specific for the sperm whale myoglobin 67-79 peptide and could be partially activated by a peptide analogue, equine myoglobin with a natural 74G substitution. Using this hybridoma in T cell activation assays, we studied the effects of varying the avidity of the TCR for its ligand, the concentration of MHC:peptide complex on the APC, and the density of TCR on the surface. Varying ligand concentration on the surface of the APC, the TCR avidity, or the density of TCR on the T cell were equally important parameters in driving T cell activation. The mouse myoglobin (74T) analogue, however, acted as an antagonist to the T cell response. Its effectiveness was also partially determined by its ability to bind to MHC. By independently altering each of these variables and following T cell activation, we describe the interrelationships among these three components (MHC:peptide:TCR) that control the activation of the T cell.

Previously, we showed that arachidonic acid and prostaglandin metabolites inhibited GABA A responses in rat cerebral cortex. Thromboxane A 2 (TXA 2 ), a metabolite of arachidonic acid, has potent actions on blood vessels and platelets, but its actions on neurons are not known. Here, we examined the effects of several TXA 2 analogs on the functional and binding characteristics of GABA A receptors in rat brain. The stable analogs of TXA 2 , pinane and carbocyclic TXA 2 , and the TXA 2 agonist, U-46619, inhibited muscimol-induced 36 Cl − uptake in cerebral cortical synaptoneurosomes. Carbocyclic TXA 2 decreased the maximal response to muscimol, consistent with a non-competitive interaction. The TXA 2 antagonist, SQ 25,548, did not block the effects of either arachidonic acid or carbocyclic TXA 2 . Neither the biologically inactive metabolite of TXA 2 , TXB 2 , nor carbacyclin, a stable analog of prostacyclin (prostaglandin I 2 ) had an effect on GABA A responses. Thus the pharmacology differs from that in vascular smooth muscle and platelets. To determine if GABA A receptors were sensitive to the thromboxanes, the effect of pinane TXA 2 on the binding of [ 35 S] t -butylbicyclophosphorothionate ([ 35 S]TBPS) to GABA-gated Cl − channels was measured using receptor autoradiography. Pinane TXA 2 inhibited [ 35 S]TBPS binding in a regionally selective and non-competitive manner; the greatest inhibition was in the cerebral cortex, hippocampus and striatum, areas which are selectively vulnerable to cerebral ischemia. We conclude that TXA 2 can interact with neuronal membranes to inhibit GABA receptor function, independent of its actions on the cerebrovasculature and on glial cells. This may be important during pathologic states such as ischemia, when TXA 2 accumulates in extracellular spaces. Copyright © 1996 Elsevier Science Ltd.

We describe our 3-year experience using spiral CT in the evaluation of small renal masses in order to determine the usefulness of this technique for classifying the lesions and to correlate specific CT features with pathologic findings.We retrospectively analyzed spiral CT scans and results of pathologic examinations of surgically extirpated small (or = 3 cm) renal masses in 35 patients. The masses included 27 renal cell carcinomas, two transitional cell carcinomas, one leiomyoma, one angiomyolipoma, and four benign cysts. Several imaging features, including attenuation, pattern of contrast enhancement, presence and type of calcification, cyst wall, and septation, were correlated with pathologic findings.Most renal cell carcinomas had a solid growth pattern (n = 19), had attenuation values on unenhanced scans of 20 H or greater (n = 26), and had attenuation values that increased by at least 10 H with contrast enhancement (n = 26). Only three renal cell carcinomas were mostly cystic on pathologic examination. Heterogeneous enhancement correlated with the presence of acellular regions (p = .02). Of 12 cystic masses, spiral CT showed the absence of a thick or nodular fibrous capsule in seven of nine masses (specificity, 0.78) and the absence of several (or nodular) septations in six of seven masses (specificity, 0.86) but was not as sensitive in detecting these features.Spiral CT can show many of the key imaging features of small renal masses used to distinguish between benign and malignant lesions. However, despite the theoretical benefits of volumetric CT, some lesions remain indeterminate and require surgical removal for diagnosis.

A scanning force microscope for measuring ultrafast voltage signals is demonstrated. The new technique is based on mixing due to the square-law force interaction present between the microscope tip and sample. Examples of time-resolved measurements on VLSI and MMIC devices are given.

Launch into education about pharmacology (LEAP) is an inquiry-based science enrichment program designed to enhance competence in biology and chemistry and foster interest in science careers especially among under-represented minorities. The study of how drugs work, how they enter cells, alter body chemistry, and exit the body engages students to conceptualize fundamental precepts in biology, chemistry, and math. Students complete an intensive three-week course in the fundamentals of pharmacology during the summer followed by a mentored research component during the school year. Following a 5E learning paradigm, the summer course captures student interest by introducing controversial topics in pharmacology and provides a framework that guides them to explore topics in greater detail. The 5E learning cycle is recapitulated as students extend their knowledge to design and to test an original research question in pharmacology. LEAP students demonstrated significant gains in biology and chemistry knowledge and interests in pursuing science. Several students earned honors for the presentation of their research in regional and state science fairs. Success of the LEAP model in its initial 2 years argues that coupling college-level coursework of interest to teens with an authentic research experience enhances high school student success in and enthusiasm for science.

A number of aspects of the natural biology of herpes simplex virus (HSV) make it an attractive candidate for a vector to express foreign genes within the nervous system. Some of the advantages of an HSV vector are 1 Establishment of a life-long latent infection within peripheral and central nervous system neurons (for a review, see ref,1); 2 Latent HSV genomes exist as multiple episomal copies/neuron and integration is not known to occur (2), and 3. Nonreplicating HSV recombinants can establish a latent infection efficiently (3).

Immunization of normal mice with bacterial DNA induces a significant anti-DNA response that includes antibodies resembling some lupus anti-DNA in their binding properties, although lacking specificity for mammalian dsDNA. To determine the structure of these induced antibodies and their relationship to anti-DNA from lupus mice, we have characterized the clonality and selected V-region sequences of a panel of 20 anti-DNA antibodies from 3 BALB/c mice immunized with ssDNA from Escherichia coli. Southern blot analysis of H and L chain rearrangements indicated that two of the animals expressed pairs of clonally related antibodies. Amino acid sequences of 10 of the induced antibodies demonstrated predominant utilization of J558 family VH genes and JH4 in association with various DH, J kappa and V kappa genes. Among the VH CDR3 of these 10 antibodies, 4 displayed arginine residues as a result of N region additions. None of these antibodies, however, had more than one arginine residue in VH CDR3 nor arginines at positions 100 or 100a, characteristic features of lupus antibodies to dsDNA. These results suggest that normal mice immunized with bacterial DNA display certain facets of DNA Ag drive, although lacking the mechanisms for the production of antibodies to mammalian dsDNA.

This study examined the prevalence of intimate partner violence in Jordan among a sample of 517 reproductive health clinic attendees. Intimate partner violence was measured using the World Health Organization's domestic violence questionnaire which was modified by the results of focus group discussions conducted in Amman. The percentages of women experiencing at least 1 form of control or violence since marriage were: control, 97.2%; psychological violence, 73.4%; physical violence, 31.2%; and sexual violence, 18.8%. Modifications of the WHO questionnaire were needed to measure control and psychological violence in Jordan. Similar modifications might be required when conducting research in the Region.