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Verapamil and vasospastic angina： underuse in the elderly population

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journal of Geriatric Cardiology 2017年第7期14卷 430-435页

作者： Xavier humbert Vincent Roule Paul Milliez joachim Alexandre Department of General Medicine Medical School Caen France Department of Pharmacology CHU de Caen Caen France Normandie University UNICAEN CHU Caen Signalisation eleetrophysiologie et imagerie des lesions d'ischOmie-reperfusion myocardique Caen France Department of Cardiology CHU de Caen Caen France

The first case of Prinzmetal angina was described in 1959 by Prinzmetal, et al. Since this description, several triggering factors have been associated with vasospastic angina （VA） and included： illicit drugs such as cocaine, amphetamine or marijuana, but also bitter-orange, alcohol, butane, chemotherapy drugs, over-the-counter medication and different antibiotics. Smoking is also a major risk factor for developing VA.t21 Thus, except for smoking, many of conventional atherosclerosis risk factors do not appear to be applicable to VA.t21 However, vasospastic angina can also occur without any triggering factor.

关键词： Calcium antagonists Elderly population Prinzmetal angina Variant angina Verapamil

Single-cell systems neuroscience:A growing frontier in mental illness

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BIOCELL 2022年第1期46卷 7-11页

作者： sean j.O’SULLIVAN Daniel Baugh Institute for Functional Genomics and Computational Biology Department of PathologyAnatomy and Cell BiologyThomas Jefferson UniversityPhiladelphiaUSA Brain Stimulation Laboratory Stanford UniversityStanfordUSA

The development of effective treatments for psychiatric disease has been disappointing in recent decades given the advancements in ***,rising rates of mental ilness such as addiction and depression compel scientists and physicians to discover novel and creative *** such approach that has proven effective is systems neuroscience:A focus on networks as opposed to ***,investigation at the single-cell and circuit level is likely to be fruitful in such endeavors as this resolution describes the functional psychopathology that allows for intervention.

关键词： Systems biology Systemsneuroscience Single-cellpsychiatry Psychopathology

VOC removal from contaminated groundwater through membrane pervaporation. (Ⅱ): 1,1,1-trichloroethane-SDS surfactant solution system

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journal of Environmental Sciences 2003年第6期15卷 821-826页

作者： sean LIU Department of Food Science Rutgers University

The conventional “pump-and-treat' technology for subsurface remediation of groundwater contaminated with volatile organic compounds(VOCs) such as 1,1,1-trichloroethane(TCA), a common chlorinated organic solvent, has limitation of prohibitively long treatment time due to extremely low water solubility of the VOCs. Surfactant-based soil remediation has emerged as the effective technology that substantially reduces the treatment time. In order to make the whole process economical, the surfactant used in soil washing has to be recovered and reused. This study examined the recovery of anionic surfactant, sodium dodecyl sulfate(SDS), from soil remediation fluids containing TCA, using a bench-scale membrane pervaporation unit. The effects of high TCA concentration, surfactant dosage, and flow rate on permeation flux and selectivity(α value) of the process were evaluated. In general, higher surfactant concentration yielded lower TCA flux and constant water flux, resulting in declining α values; higher flow rate of TCA feed stream results in higher VOC flux and selectivity, an indication of the effect of concentration polarization; higher TCA feed concentration produces higher TCA permeation across the membrane, however, the selectivity was virtually unchanged unless the total TCA concentration exceeded 2000 ppm.

关键词： pervaporation VOCs SDS surfactant groundwater remediation 1,1,1-trichloroethane

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Overcoming maladaptive plasticity through plastic compensation

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Current Zoology 2013年第4期59卷 526-536页

作者： Matthew R.j. MORRIS sean M. ROGERS Department of Biological Sciences University of Calgary Calgary AB Canada T2N 1N4

Most species evolve within fluctuating environments, and have developed adaptations to meet the challenges posed by environmental heterogeneity. One such adaptation is phenotypic plasticity, or the ability of a single genotype to produce multiple environmentally-induced phenotypes. Yet, not all plasticity is adaptive. Despite the renewed interest in adaptive phenotypic plas- ticity and its consequences for evolution, much less is known about maladaptive plasticity. However, maladaptive plasticity is likely an important driver of phenotypic similarity among populations living in different environments. This paper traces four strategies for overcoming maladaptive plasticity that result in phenotypic similarity, two of which involve genetic changes （standing genetic variation, genetic compensation） and two of which do not （standing epigenetic variation, plastic compensation）. Plastic compensation is defined as adaptive plasticity overcoming maladaptive plasticity. In particular, plastic compensation may increase the likelihood of genetic compensation by facilitating population persistence. We provide key terms to disentangle these aspects of phenotypic plasticity and introduce examples to reinforce the potential importance of plastic compensation for under- standing evolutionary change

关键词： Homeostasis Canalization Ecological speciation Standing genetic variation Genetic compensation Countergradi-ent variation

MODELING HEADCUT DEVELOPMENT AND MIGRATION IN UPLAND CONCENTRATED FLOWS

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International journal of Sediment Research 2005年第4期20卷 281-294页

作者： sean j. BENNETT Carlos V. ALONSO Department of Geography University at Buffalo Buffalo NY 14261-0055 USA USDA-ARS National Sedimentation Laboratory P.O. Box 1157 Oxford MS 38655

On hillslopes and agricultural fields, discrete areas of intense, localized soil erosion commonly take place in the form of migrating headcuts. These erosional features significantly increase soil loss and landscape degradation, yet the unsteady, transient, and migratory habits of headcuts complicate their phenomenological and erosional characterization. Here a unique experimental facility was constructed to examine actively migrating headcuts typical of upland concentrated flows. Essential components of the facility include a deep soil cavity with external drainage, rainfall simulator, capacity for overland flow, and a video recording technique for data collection. Results from these experiments show that: (1) after a short period of adjustment, headcut migration attained a steady-state condition, where the rate of migration, scour hole geometry, and sediment discharge remain constant with time; (2) boundary conditions of higher rates of overland flow, steeper bed slopes, and larger initial headcut heights produced systematically larger scour holes with higher rates of soil erosion; and (3) during migration, the turbulent flow structure within the scour hole remained unchanged, consisting of an overfall nappe at the brink transitioning into a reattached wall jet with two recirculation eddies within the plunge pool. The systematic behavior of headcut development and migration enabled the application of modified jet impingement theory to predict with good success the characteristics of the impinging jet, the depth of maximum scour, the rate of headcut migration, and the rate of sediment erosion. These laboratory data and the analytical formulation can be used in conjunction with soil erosion prediction technology to improve the management of agricultural areas impacted by headcut development and ephemeral gully erosion.

关键词： Soil erosion Headcuts Rills Gullies jet impingement

The N-terminus of COX-1 and its effect on cyclooxygenase-1 catalytic activity

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journal of Genetics and Genomics 2010年第2期37卷 117-123页

作者： sean Phipps Michael j. Turner Daniel L. Simmons Chemistry and Biochemistry Department Brigham Young University

Cyclooxygenases are encoded by COX-1 and COX-2. They share over sixty percent sequence identity in human and are similar to each other in their crystallographic structures. One major difference in the primary structure of these two isozymes is the presence of eight amino acids in the amino-terminal region of COX-1 that are not present in COX-2. The function of this amino acid sequence is unknown. In this study, a human COX-1 mutant （Δ7aa） with this sequence removed was studied in parallel with COX-1. Signal peptide cleavage, N-linked glycosylation, protein expression, distribution and dimerization were not affected by the mutation. The mutant was enzymati-cally active and showed the same sensitivity toward aspirin. The KM for the enzyme remained the same as COX-1. However, the Vmax of the COX-1 mutant decreased by 3.3-fold. We conclude that the COX-1 specific amino-terminal sequence has a subtle but detectable effect on COX-1 catalysis.

关键词： COX-1 COX-2 dimerization glycosylation aspirin KM Vmax

Adenosine-treated bioprinted muscle constructs prolong cell survival and improve tissue formation

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Bio-Design and Manufacturing 2021年第3期4卷 441-451页

作者： Dongxu Ke Adam M.jorgensen Sang j.Lee james j.Yoo sean V.Murphy Wake Forest Institute for Regenerative Medicine Wake Forest School of MedicineWinston-SalemNCUSA Novaprint Therapeutics Suzhou Co. LtdSuzhouJiangsuChina

It is crucial to maintaining the viability of biofabricated human-sized tissues to ensure their successful survival and function after *** is a purine nucleoside that has the function to suppress cellular metabolism and has been previously proposed as a method to prolong cell viability under *** this study,we optimized the dose concentration of adenosine for incorporation into bioprinted constructs to preserve long-term cell viability in *** results showed that muscle cells(C2C12)containing 6,7,or 8 mM adenosine maintained high cell viability for 20 days under hypoxic conditions(0.1%O2),whereas cells without adenosine treatment showed 100%cell death after 11 *** 20 days under hypoxic conditions,muscle cells treated with adenosine proliferated and differentiated when transferred to normoxic *** these adenosine concentrations,6 mM was picked as the optimized adenosine concentration for further investigations due to its most effective results on improving cell *** bioprinted muscle constructs containing adenosine(6 mM)maintained high cell viability for 11 days under hypoxic conditions,while the control constructs without adenosine had no live *** in vivo validation,the bioprinted constructs with adenosine implanted under the dorsal subcutaneous space in mice,showed the enhanced formation of muscle tissue with minimal central necrosis and apoptosis,when compared to the constructs without *** positive in vitro and in vivo results demonstrate that the use of adenosine is an effective approach to preventing the challenge of hypoxia-induced necrosis in bioprinted tissues for clinical translation.

关键词： Bioprinting Hypoxia Adenosine Cell viability In vivo

Molten salt assisted self-activated carbon with controllable architecture for aqueous supercapacitor

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journal of Materials Science & Technology 2023年第25期156卷 107-117页

作者： Wei Zhang Wenxian Li sean Li School of Materials Science and Engineering The University of New South WalesKensingtonNew South Wales 2052Australia UNSW Materials and Manufacturing Futures Institute The University of New South WalesKensingtonNew South Wales 2052Australia

Activated carbons have been widely employed as electrode materials of aqueous supercapacitors but the use of hazardous and corrosive activating agents challenges conventional activation ***,using a unique molten salt assisted self-activation technique,we have devised an eco-friendly and simple method to synthesize oxygen-rich hierarchical porous carbon with controllable *** of sodium carboxymethylcellulose and NaCl was pyrolyzed in one step,creating in-situ produced Na_(2)CO_(3)-NaCl molten salt that carried out the activation ***2 CO3 acts as the activating agent in the reaction media of NaCl during the self-activation *** obtained carbon exhibited a remarkable specific capacitance of 278 F g^(−1) at 0.5 A g^(−1) and retained 76%capacitance at 50 A g^(−1) in a three-electrode *** fabricated aqueous coin cell achieved 81%capacitance retention at 50 A g^(−1) and the highest specific energy density of 12.8 Wh kg^(−1) at 214.6 W kg^(−1),which are superior compared to the commercial activated carbon(64%at 50 A g^(−1) and 8.4 Wh kg^(−1) at 194.8 W kg^(−1)).Moreover,capacitance fading was not observed after 10000 cycles at 5 A g^(−1).Considering the species diversity and low cost of self-salt polymers on the market,this strategy will expect to become a scalable approach for synthesizing high-performance capacitive carbons.

关键词： Molten salt Self-template Porous carbon Controllable architecture Aqueous supercapacitors

Sex differences in the influence of social context, salient social stimulation and amphetamine on ultrasonic vocalizations in prairie voles

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Integrative Zoology 2014年第3期9卷 280-293页

作者： sean T.MA Shanna L.RESENDEZ Brandon j.ARAGONA Department of Psychology Program in Neuroscience University of MichiganAnn ArborMIUSA

Prairie voles(Microtus ochrogaster)are a socially monogamous rodent species and their cooperative behaviors require extensive communication between *** use ultrasonic vocalizations(USVs)to communicate and because a prairie vole breeder pair must engage in extensive cooperation for successful reproduction,auditory communication may be critical for this ***,we sought to characterize USVs in adult male and female prairie voles,and to determine how these calls are influenced by social context,salient social stimuli and the psychostimulant drug of abuse amphetamine(AMPH).Here,we characterize prairie vole USVs by showing the range of frequencies of prairie vole USVs,the proportion of various call types,how these call types compare between males and females,and how they are influenced by social stimulation and *** caused a robust increase in the number of USVs in both males and females and there was a dramatic sex difference in the complexity of call structures of AMPH-induced USVs,with males emitting more elaborate ***,we show that novel(***)social cues evoked differential increases in USVs across sex,with males showing a much more robust increase in USV production,both with respect to the frequency and complexity of USV *** to an estrous female in particular caused an extraordinary increase in USVs in male *** data suggest that USVs may be a useful measure of social motivation in this species,including how social behaviors can be impacted by drugs of abuse.

关键词： amphetamine dopamine mate choice pair bonding ultrasonic vocalization