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1.
J STEM Outreach ; 4(1)2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34927016

RESUMO

STEM internships for both high school and college students provide early opportunities for students to discover careers of interest and career paths they may not otherwise experience. For over 25 years, the University of Alabama at Birmingham's (UAB) Center for Community OutReach Development (CORD) has provided rising high school seniors with opportunities to conduct research in federally-funded laboratories under the mentorship of UAB faculty. This paper evaluates CORD's High School Summer Science Institute III Program (SSI III) and its impact on participants' STEM career trajectories. Outcomes were tracked for SSI III participants over an eight-year period, and former interns' perceptions of the program reported. Over 99% of surveyed interns (N=102) chose a STEM undergraduate major, and 97% of the former interns reported they were pursuing STEM careers. Nearly all interns indicated their SSI-III experience was very positive and influenced their career decision. Over half of the interns matriculated into an undergraduate STEM major at UAB, providing the university with return as more excellent students for their investment in the program. These results highlight the importance of high school student involvement in STEM internships as a pathway that leads towards STEM careers.

2.
J STEM Outreach ; 4(3)2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35071997

RESUMO

A year of COVID-19 quarantine required educators to switch from in-person to virtual learning platforms, causing a dramatic reimagining of their daily praxis. Their experiences are likely to influence new norms for K-12 education. While virtual learning can be effective, student engagement, student retention, and student attention can be challenging. This paper discusses how we adapted a materials-heavy, hands-on, annual summer teacher professional development (PD) program from an in-person to a virtual platform in the initial months of the pandemic. We successfully maintained effective and hands-on components, giving authentic learning experiences to the participants. The 2020 virtual version of the program effectively engaged in-service teachers with high daily participation and retention rates. Nearly all participants rated the workshops as very good or excellent, and an assessment of participants' learning outcomes was comparable to that of the highly-rated in-person 2018 version of the program. Following the PD session, teachers reported feeling more prepared to facilitate their students' learning, increased inquiry-based science teaching knowledge and skills, and their enthusiasm for utilizing workshop strategies. While there are challenges to implementing virtual learning, virtual teacher PD can be widely adaptable and replicable for many institutions, especially in situations in which distance or finances deter in-person participation.

3.
BMC Geriatr ; 20(1): 252, 2020 07 23.
Artigo em Inglês | MEDLINE | ID: mdl-32703167

RESUMO

BACKGROUND: Given an increase in the aging population and its impact on healthcare systems, policy makers for provision of health and social services are aiming to keep older adults in good health for longer, in other words towards 'healthy aging'. Our study objective is to show that rehabilitation with cochlear implant treatment in the elderly with hearing impairment improves the overall health-related quality of life and general well-being that translate into healthy aging. METHODS: The multicentre, prospective, repeated measures, single-subject, clinical observational study will accrue 100 elderly, first-time, unilateral CI recipients (≥ 60 years) and analyze changes on specific measurement tools over ca. 20 months from preimplant to postimplant. Evaluations will consist of details collected through case history and interview questionnaires by clinicians, data logging, self-report questionnaires completed by the recipients and a series of commonly used audiometric measures and geriatric assessment tools. The primary indicator of changes in overall quality of life will be the HUI-3. DISCUSSION: The protocol is designed to make use of measurement tools that have already been applied to the hearing-impaired population in order to compare effects of CI rehabilitation in adults immediately before their implantation, (pre-implant) and after gaining 1-1.5 years of experience (post-implant). The broad approach will lead to a greater understanding of how useful hearing impacts the quality of life in elderly individuals, and thus improves potentials for healthy aging. Outcomes will be described and analyzed in detail. TRIAL REGISTRATION: This research has been registered in ClinicalTrials.gov (http://www.clinicaltrials.gov/), 7 March 2017 under the n° NCT03072862 .


Assuntos
Implante Coclear , Implantes Cocleares , Envelhecimento Saudável , Percepção da Fala , Idoso , Humanos , Estudos Prospectivos , Qualidade de Vida , Resultado do Tratamento
4.
Physiol Behav ; 199: 375-385, 2019 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-30529343

RESUMO

We previously demonstrated independent effects of early-life experience (ELE) and trait aggression (TA) on resting heart rate (HR) and mean arterial pressure (MAP) in rats. The present study examined the effects of TA and ELE on stress-evoked cardiovascular reactivity and recovery. Pups born to Wistar-Kyoto dams were exposed to daily 180-min periods of maternal separation (MS) during the first two weeks of life, and aggression was assessed in adult offspring using the resident-intruder test. Radiotelemetry was then used to record stress-evoked HR and MAP responses in response to: strobe light, novel environment, intruder rat, or restraint. Maximal HR and MAP responses were quantified as indices of reactivity, and exponential decay curves were fitted to determine decay constants as a measure of recovery. Strobe light was the weakest stressor, evoking the lowest increases in MAP and HR, which were significantly greater in MS-exposed rats irrespective of TA. In contrast, reactivity to and recovery from exposure to a novel environment or an intruder were significantly influenced by TA, but not ELE. TA animals exhibited greater reactivity in both of these paradigms, with either decreased (novel environment) or increased (intruder) recovery. Restraint stress induced the largest changes in HR and MAP with the slowest recovery, and these responses were shaped by a significant ELE x TA interaction. These data indicate that cardiovascular reactivity and recovery are influenced by ELE, TA, or ELE x TA interaction depending on stressor aversiveness as well as its physical and psychological dimensions.


Assuntos
Agressão/fisiologia , Pressão Sanguínea/fisiologia , Frequência Cardíaca/fisiologia , Privação Materna , Personalidade/fisiologia , Animais , Comportamento Animal/fisiologia , Meio Ambiente , Feminino , Masculino , Ratos , Ratos Endogâmicos WKY , Restrição Física , Estresse Psicológico/fisiopatologia
5.
J STEM Outreach ; 1(1)2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31517251

RESUMO

This study describes a program that the University of Alabama at Birmingham (UAB) carried out in partnership with Birmingham City Schools (BCS) to test an educational intervention, i.e., Hands-On Physics (HOP), among 8th grade students in predominantly minority schools. It also evaluated teachers' demographics and educational backgrounds. The students conducted four physics experiments during a three day period. They performed better on post-tests. The actual and the percent gains in knowledge for each school were essentially equal for the schools that had passing versus failing grades in annual state assessment (20.4±5.6/49.0±5.6%, 20.4±2.7/48.4±8.3%, respectively). Most students (53%) stated that they were comfortable with science, 88% indicated that they were planning to enter higher education, and 86% agreed that higher education was very important for their future. The students' major perceived obstacles to higher education were education cost and low grades. The teachers were primarily between 40-59 years old (60%), female (80%) and African-American (93%), and 87% majored in biology (93%). Forty percent had a bachelor's degree and 60% had a master's degree. They reported that they needed more support teaching physics and reported that a lack of materials and time were the main obstacles to provide the highest quality science educational experiences.

6.
Adv Exp Med Biol ; 975 Pt 1: 27-37, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28849441

RESUMO

This study tests the hypothesis that taurine supplementation reduces sugar-induced increases in renal sympathetic nerve activity related to renin release in adult male rats. After weaning, male rats were fed normal rat chow and drank water containing 5% glucose (CG) or water alone (CW) throughout the experiment. At 6-7 weeks of age, each group was supplemented with or without 3% taurine in drinking water until the end of experiment. At 7-8 weeks of age, blood chemistry and renal nerve activity were measured in anesthetized rats. Body weights slightly and significantly increased in CG compared to CW groups but were not significantly affected by taurine supplementation. Plasma electrolytes except bicarbonate, plasma creatinine, and blood urea nitrogen were not significantly different among the four groups. Mean arterial pressure significantly increased in both taurine treated groups compared to CW, while heart rates were not significantly different among the four groups. Further, all groups displayed similar renal nerve firing frequencies at rest and renal nerve responses to sodium nitroprusside and phenylephrine infusion. However, compared to CW group, CG significantly increased the power density of renin release-related frequency component, decreased that of sodium excretion-related frequency component, and decreased that of renal blood flow-related frequency component. Taurine supplementation completely abolished the effect of high sugar intake on renal sympathetic activity patterns. These data indicate that in adult male rats, high sugar intake alters the pattern but not firing frequency of sympathetic nerve activity to control renal function, and this effect can be improved by taurine supplementation.


Assuntos
Glucose/toxicidade , Rim/efeitos dos fármacos , Sistema Nervoso Simpático/efeitos dos fármacos , Taurina/farmacologia , Animais , Dieta/efeitos adversos , Rim/inervação , Masculino , Ratos , Ratos Sprague-Dawley
7.
Adv Exp Med Biol ; 975 Pt 2: 741-755, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28849496

RESUMO

Perinatal taurine depletion followed by high sugar intake after weaning adversely affects myocardial and arterial pressure function following a myocardial ischemia and reperfusion (IR) insult in adult female rats. This study tests the hypothesis that taurine supplementation ameliorates this adverse effect. Female Sprague-Dawley rats were fed normal rat chow and drank water containing ß-alanine from conception until weaning (taurine depletion, TD). After weaning, female offspring were fed normal rat chow and drank either water containing 5% glucose (TDG) or water alone (TDW). At 6-7 weeks of age, half the rats in each group were supplemented with taurine and 1 week later subjected to cardiac IR. Body weight, heart weight, plasma electrolytes, plasma creatinine, blood urea nitrogen, and hematocrit were not significantly different among the four groups. The mean arterial pressures significantly increased in all groups after IR, but values were not significantly different among the four groups. Heart rates were significantly increased after IR only in TDW group. Compared to TDW, TDG displayed increased plasma cardiac injury markers (creatinine kinase-MB, troponin T, and N-terminal prohormone brain natriuretic peptide), increased sympathetic activity, decreased parasympathetic activity, and decreased baroreflex sensitivity after IR. Taurine supplementation completely restored the baroreflex and autonomic dysfunction of TDG to TDW levels and partially decreased myocardial injury after cardiac IR. The present study indicates that in adult female rats, perinatal taurine depletion followed by high sugar intake after weaning exacerbates cardiac IR injury and arterial pressure dysregulation and these adverse effects can be partially prevented by taurine supplementation.


Assuntos
Traumatismo por Reperfusão Miocárdica , Efeitos Tardios da Exposição Pré-Natal , Taurina/farmacologia , Animais , Barorreflexo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Feminino , Glucose/toxicidade , Frequência Cardíaca/efeitos dos fármacos , Gravidez , Ratos , Ratos Sprague-Dawley , Taurina/deficiência
8.
Adv Exp Med Biol ; 975 Pt 2: 757-768, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28849497

RESUMO

This study tests the hypothesis that perinatal taurine supplementation followed by a high sugar diet since weaning impairs renal function via renin-angiotensin system (RAS) overactivity in adult female rats. Female Sprague-Dawley rats were fed normal rat chow and given water alone or water containing 3% taurine from conception until weaning. After weaning, the female rats received normal rat chow and water with (CG, TSG) or without (CW, TSW) 5% glucose throughout the experiment. At 7-8 weeks of age, renal function at rest and after an acute saline load was tested in conscious female rats after a week of captopril treatment. Body, heart, and kidney weights were not significantly different among the eight groups. Mean arterial pressures and heart rates were also not different among the groups. While effective renal blood flow did not significantly differ among the eight groups, TSG displayed higher renal vascular resistance compared to CW, CG, and TSW groups. Glomerular filtration rate, filtration fraction, and water and sodium excretion did not significantly differ among the groups. Compared to CW, the saline load significantly depressed fractional water excretion in CG and TSW and fractional sodium excretion in CG, TSW, and TSG groups. Captopril treatment abolished these differences but significantly decreased potassium excretion in CG, TSW, and TSG compared to CW and abolished the increased fractional potassium excretion in TSG compared to CG and TSW groups. These data strongly suggest that in adult female rats, perinatal taurine supplementation, particularly followed by high sugar intake, alters renal function via altered RAS activity.


Assuntos
Rim/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Sistema Renina-Angiotensina/efeitos dos fármacos , Taurina/farmacologia , Animais , Feminino , Glucose/toxicidade , Gravidez , Ratos , Ratos Sprague-Dawley
9.
Adv Exp Med Biol ; 975 Pt 2: 769-787, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28849498

RESUMO

This study tests the hypothesis that perinatal taurine imbalance impairs renal function in adult female rats via alterations in estrogen activity. Female Sprague-Dawley rats were fed normal rat chow and water containing 3% beta-alanine (TD), 3% taurine (TS) or water alone (C) from conception until weaning. Then, female offspring received normal rat chow and water with (CG, TDG, TSG) or without (CW, TDW, TSW) 5% glucose. At 7-8 weeks of age, renal function at rest and after acute saline load was tested in conscious, restrained female rats treated with non-selective estrogen receptor blocker tamoxifen for a week. Compared to control, TD or TS did not affect mean arterial pressure (MAP). Tamoxifen significantly increased resting MAP only in TDG compared to TDW groups. Although renal blood flow did not significantly differ among the groups, renal vascular resistance increased in TSG compared to CW, CG, and TSW groups. Glomerular filtration rate and water and sodium excretion were not significantly different among the groups. Compared to CW, saline load significantly depressed fractional water excretion in CG, TDW, TDG, and TSW, and fractional sodium excretion in CG, TDW, TDG, TSW, and the TSG groups. Potassium excretion was not significantly different among the corresponding groups. Fractional potassium excretion significantly increased in TDW compared to CG and in TSG compared to CG and TSW groups. These differences were abolished by tamoxifen treatment. These data indicate that in adult female rats, perinatal taurine imbalance, particularly followed by high sugar intake, alters renal function via an estrogenic mechanism.


Assuntos
Estrogênios/metabolismo , Rim/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal , Taurina/metabolismo , Animais , Feminino , Glucose/toxicidade , Gravidez , Ratos , Ratos Sprague-Dawley
10.
Int J Cardiol ; 226: 87-92, 2017 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-27792993

RESUMO

BACKGROUND: Rural compared to urban Thai populations have a higher incidence of sudden unexplained nocturnal death syndrome (SUNDS). This study tests the hypothesis that compared to young urban Thai men, the young rural northeast Thai men display autonomic system dysfunction that may contribute to their relatively high risk to develop SUNDS. METHODS: Forty-seven healthy second and third year students from Khon Kaen University (20-22years old) were divided into central, urban northeastern, and rural northeastern groups, based on the locality in which they had grown up and in which their parents had lived prior to their birth. RESULTS: Body weight, body height, serum sodium, serum potassium, fasting blood sugar, glucose tolerance, resting mean arterial pressure, resting heart rate, ulnar nerve conduction velocity, and sympathetic and parasympathetic nervous system activity were not significantly different among the three groups. In contrast, compared to urban northeasterners and central Thais, rural northeasterners displayed low sympathetic and high parasympathetic responses to cold stress and oral saline load; however, baroreflex sensitivity and the autonomic nervous system responses to upright tilt were not significantly different among the three groups. In addition, respiratory rates at rest and in response to upright tilt, cold stress, and oral saline load were not significantly different among the three groups. CONCLUSIONS: These data indicate that compared to central or urban, individuals from rural origin display decreased sympathetic and increased parasympathetic responses to stresses. These altered responses could predispose the individuals to inappropriate autonomic control during the stresses, including those resulting in SUNDS.


Assuntos
Doenças do Sistema Nervoso Autônomo/epidemiologia , Doenças do Sistema Nervoso Autônomo/fisiopatologia , Síndrome de Brugada/epidemiologia , Síndrome de Brugada/fisiopatologia , População Rural , Doenças do Sistema Nervoso Autônomo/diagnóstico , Barorreflexo/fisiologia , Pressão Sanguínea/fisiologia , Síndrome de Brugada/diagnóstico , Frequência Cardíaca/fisiologia , Humanos , Masculino , Fatores de Risco , População Rural/tendências , Tailândia , Adulto Jovem
11.
Eur J Neurosci ; 44(10): 2829-2845, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27643783

RESUMO

Early-life stress (ELS) can alter neurodevelopment in variable ways, ranging from producing deleterious outcomes to stress resilience. While most ELS studies focus on its harmful effects, recent work by our laboratory and others shows that ELS elicits positive effects in certain individuals. We exposed Wistar Kyoto (WKY) rats, known for a stress reactive, anxiety/depression-like phenotype, to maternal separation (MS), a model of ELS. MS exposure elicited anxiolytic and antidepressant behavioral effects as well as improved cardiovascular function in adult WKY offspring. This study interrogates an epigenetic mechanism (DNA methylation) that may confer the adaptive effects of MS in WKY offspring. We quantified global genome methylation levels in limbic brain regions of adult WKYs exposed to daily 180-min MS or neonatal handling from postnatal day 1-14. MS exposure triggered dramatic DNA hypermethylation specifically in the hippocampus. Next-generation sequencing methylome profiling revealed reduced methylation at intragenic sites within two key nodes of insulin signaling pathways: the insulin receptor and one of its major downstream targets, mitogen-activated protein kinase kinase kinase 5 (Map3k5). We then tested the hypothesis that enhancing DNA methylation in WKY rats would elicit adaptive changes akin to the effects of MS. Dietary methyl donor supplementation improved WKY rats' anxiety/depression-like behaviors and also improved cardiovascular measures, similar to previous observations following MS. Overall, these data suggest a potential molecular mechanism that mediates a predicted adaptive response, whereby ELS induces DNA methylation changes in the brain that may contribute to successful stress coping and adaptive physiological changes in adulthood.


Assuntos
Metilação de DNA , Hipocampo/metabolismo , Privação Materna , Estresse Psicológico/genética , Animais , Epigênese Genética , Feminino , Hipocampo/crescimento & desenvolvimento , Sistema de Sinalização das MAP Quinases , Masculino , Ratos , Ratos Endogâmicos WKY , Receptor de Insulina/genética , Receptor de Insulina/metabolismo , Estresse Psicológico/etiologia
12.
Am J Physiol Regul Integr Comp Physiol ; 311(2): R272-86, 2016 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-27280432

RESUMO

Early-life experience (ELE) can significantly affect life-long health and disease, including cardiovascular function. Specific dimensions of emotionality also modify risk of disease, and aggressive traits along with social inhibition have been established as independent vulnerability factors for the progression of cardiovascular disease. Yet, the biological mechanisms mediating these associations remain poorly understood. The present study utilized the inherently stress-susceptible and socially inhibited Wistar-Kyoto rats to determine the potential influences of ELE and trait aggression (TA) on cardiovascular parameters throughout the lifespan. Pups were exposed to maternal separation (MS), consisting of daily 3-h separations of the entire litter from postnatal day (P)1 to P14. The rats were weaned at P21, and as adults were instrumented for chronic radiotelemetry recordings of blood pressure and heart rate (HR). Adult aggressive behavior was assessed using the resident-intruder test, which demonstrated that TA was independent of MS exposure. MS-exposed animals (irrespective of TA) had significantly lower resting HR accompanied by increases in HR variability. No effects of MS on resting blood pressure were detected. In contrast, TA correlated with increased resting mean, systolic, and diastolic arterial pressures but had no effect on HR. TA rats (relative to nonaggressive animals) also manifested increased wall-to-lumen ratio in the thoracic aorta, increased sensitivity to phenylephrine-induced vascular contractility, and increased norepinephrine content in the heart. Together these data suggest that ELE and TA are independent factors that impact baseline cardiovascular function.


Assuntos
Agressão/fisiologia , Envelhecimento/fisiologia , Emoções/fisiologia , Coração/fisiologia , Acontecimentos que Mudam a Vida , Privação Materna , Animais , Comportamento Animal/fisiologia , Pressão Sanguínea/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Masculino , Ratos , Ratos Endogâmicos WKY
13.
Mov Disord ; 31(11): 1633-1639, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27241685

RESUMO

INTRODUCTION: DYT1 dystonia is an autosomal-dominant movement disorder characterized by abnormal, often repetitive, movements and postures. Its hallmark feature is sustained or intermittent contractions of muscles involving co-contractions of antagonist muscle pairs. The symptoms are relieved with the anticholinergic drug trihexyphenidyl. The primary mutation is a trinucleotide deletion (ΔGAG) in DYT1/TOR1A, which codes for torsinA. Previous studies showed that (1) heterozygous Dyt1 ΔGAG knock-in mice, which have an analogous mutation in the endogenous gene, exhibit motor deficits and altered corticostriatal synaptic plasticity in the brain and (2) these deficits can be rescued by trihexyphenidyl. However, brain imaging studies suggest that the Dyt1 knock-in mouse models nonmanifesting mutation carriers of DYT1 dystonia. The aim of this work was to examine the hallmark features of DYT1 dystonia in the Dyt1 knock-in mice by analyzing muscular activities. METHODS: Wireless telemetry devices with biopotential channels were implanted to the bicep and the rectus femori muscles in Dyt1 knock-in mice, and muscular activities were recorded before and after trihexyphenidyl administration. RESULTS: (1) Consistent with DYT1 dystonia patients, Dyt1 knock-in mice showed sustained contractions and co-contractions of the antagonistic bicep femoris and rectus femoris. (2) The abnormal muscle contractions were normalized by trihexyphenidyl. CONCLUSION: The results suggest that the motor deficits in Dyt1 knock-in mice are likely produced by abnormal muscle contractions, and Dyt1 knock-in mice can potentially be used as a manifesting disease model to study pathophysiology and develop novel therapeutics. © 2016 International Parkinson and Movement Disorder Society.


Assuntos
Distonia Muscular Deformante , Distonia , Doença de Parkinson , Animais , Humanos , Camundongos , Camundongos Transgênicos , Chaperonas Moleculares
14.
Adv Physiol Educ ; 40(1): 110-5, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26873898

RESUMO

"Sickle cell anemia: tracking down a mutation" is a full-day, inquiry-based, biology experience for high school students enrolled in genetics or advanced biology courses. In the experience, students use restriction endonuclease digestion, cellulose acetate gel electrophoresis, and microscopy to discover which of three putative patients have the sickle cell genotype/phenotype using DNA and blood samples from wild-type and transgenic mice that carry a sickle cell mutation. The inquiry-based, problem-solving approach facilitates the students' understanding of the basic concepts of genetics and cellular and molecular biology and provides experience with contemporary tools of biotechnology. It also leads to students' appreciation of the causes and consequences of this genetic disease, which is relatively common in individuals of African descent, and increases their understanding of the first principles of genetics. This protocol provides optimal learning when led by well-trained facilitators (including the classroom teacher) and carried out in small groups (6:1 student-to-teacher ratio). This high-quality experience can be offered to a large number of students at a relatively low cost, and it is especially effective in collaboration with a local science museum and/or university. Over the past 15 yr, >12,000 students have completed this inquiry-based learning experience and demonstrated a consistent, substantial increase in their understanding of the disease and genetics in general.


Assuntos
Anemia Falciforme/genética , Biologia Celular/educação , Genética/educação , Laboratórios , Mutação/genética , Aprendizagem Baseada em Problemas/métodos , Anemia Falciforme/diagnóstico , Animais , Avaliação Educacional/métodos , Feminino , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Treinamento por Simulação/métodos , Estudantes
15.
PLoS One ; 10(8): e0135030, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26244553

RESUMO

The α2 adrenergic receptor (AR) subtypes are important for blood pressure control. When activated, the α2A subtype elicits a hypotensive response whereas the α2B subtype mediates a hypertensive effect that counteracts the hypotensive response by the α2A subtype. We have previously shown that spinophilin attenuates the α2AAR-dependent hypotensive response; in spinophilin null mice, this response is highly potentiated. In this study, we demonstrate that spinophilin impedes arrestin-dependent phosphorylation and desensitization of the α2BAR subtype by competing against arrestin binding to this receptor subtype. The Del301-303 α2BAR, a human variation that shows impaired phosphorylation and desensitization and is linked to hypertension in certain populations, exhibits preferential interaction with spinophilin over arrestin. Furthermore, Del301-303 α2BAR-induced ERK signaling is quickly desensitized in cells without spinophilin expression, showing a profile similar to that induced by the wild type receptor in these cells. Together, these data suggest a critical role of spinophilin in sustaining α2BAR signaling. Consistent with this notion, our in vivo study reveals that the α2BAR-elicited hypertensive response is diminished in spinophilin deficient mice. In arrestin 3 deficient mice, where the receptor has a stronger binding to spinophilin, the same hypertensive response is enhanced. These data suggest that interaction with spinophilin is indispensable for the α2BAR to elicit the hypertensive response. This is opposite of the negative role of spinophilin in regulating α2AAR-mediated hypotensive response, suggesting that spinophilin regulation of these closely related receptor subtypes can result in distinct functional outcomes in vivo. Thus, spinophilin may represent a useful therapeutic target for treatment of hypertension.


Assuntos
Arrestinas/metabolismo , Hipertensão/metabolismo , Proteínas dos Microfilamentos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Receptores Adrenérgicos alfa 2/metabolismo , Animais , Arrestinas/deficiência , Arrestinas/genética , Ligação Competitiva , Western Blotting , Células COS , Células Cultivadas , Chlorocebus aethiops , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Células HEK293 , Humanos , Hipertensão/genética , Hipertensão/fisiopatologia , Sistema de Sinalização das MAP Quinases , Camundongos , Camundongos Knockout , Proteínas dos Microfilamentos/deficiência , Proteínas dos Microfilamentos/genética , Mutação , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Ligação Proteica , Receptores Adrenérgicos alfa 2/genética
16.
Radiat Prot Dosimetry ; 166(1-4): 388-92, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25911407

RESUMO

In recent years the use of hadrons for cancer radiation treatment has grown in importance, and many facilities are currently operational or under construction worldwide. To fully exploit the therapeutic advantages offered by hadron therapy, precise body imaging for accurate beam delivery is decisive. Proton computed tomography (pCT) scanners, currently in their R&D phase, provide the ultimate 3D imaging for hadrons treatment guidance. A key component of a pCT scanner is the detector used to track the protons, which has great impact on the scanner performances and ultimately limits its maximum speed. In this article, a novel proton-tracking detector was presented that would have higher scanning speed, better spatial resolution and lower material budget with respect to present state-of-the-art detectors, leading to enhanced performances. This advancement in performances is achieved by employing the very latest development in monolithic active pixel detectors (to build high granularity, low material budget, large area silicon detectors) and a completely new proprietary architecture (to effectively compress the data).


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Prótons , Tomógrafos Computadorizados , Tomografia Computadorizada por Raios X/instrumentação , Desenho de Equipamento , Humanos , Doses de Radiação
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