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1.
Anal Chem ; 96(16): 6097-6105, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38597398

RESUMO

This perspective encompasses a focused review of the literature leading to a tipping point in electroanalytical chemistry. We tie together the threads of a "revolution" quietly in the making for years through the work of many authors. Long-held misconceptions about the use of background subtraction in fast voltammetry are addressed. We lay out future advantages that accompany background-inclusive voltammetry, particularly when paired with modern machine-learning algorithms for data analysis.

2.
J Pediatr ; 233: 191-197.e2, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33548260

RESUMO

OBJECTIVE: To examine racial differences in tonsillectomy with or without adenoidectomy (T&A) for sleep-disordered breathing (SDB) among Medicaid-insured children. STUDY DESIGN: Retrospective analysis of the 2016 MarketScan Multistate Medicaid Database was performed for children ages 2 to <18 years with a diagnosis of SDB. Patients with medical complexity and infectious indications for surgery were excluded. Racial groups were categorized into non-Hispanic White, non-Hispanic Black, Hispanic, and other. Adjusted multivariate logistic regression was used to determine if race/ethnicity was a significant predictor of obtaining T&A, polysomnography, and time to intervention. RESULTS: There were 83 613 patients with a diagnosis of SDB that met inclusion criteria, of which 49.2% were female with a mean age of 7.9 ± 3.8 years. The cohort consisted of White (49.2%), Black (30.0%), Hispanic (8.0%), and other (13.2%) groups. Overall, 15.4% underwent T&A. Black (82.2%) and Hispanic (82.3%) children had significantly higher rates of no intervention and White patients had the lowest rate of no intervention (76.9%; P < .0001) and the highest rate of T&A (18.7%; P < .0001). Mean time to surgery was shortest in White compared with Black children (P < .0001). Logistic regression adjusting for age and sex showed that Black children had 45% reduced odds of surgery (95% CI 0.53-0.58), Hispanic 38% (95% CI 0.58-0.68), and other 35% (95% CI 0.61-0.70) compared with White children with Medicaid insurance. CONCLUSIONS: Racial and ethnic disparities exist in the utilization of T&A for children with SDB enrolled in Medicaid. Future studies that investigate possible sources for these differences and more equitable care are warranted.


Assuntos
Disparidades em Assistência à Saúde , Grupos Raciais/estatística & dados numéricos , Tonsilectomia/estatística & dados numéricos , Criança , Feminino , Humanos , Masculino , Medicaid , Estudos Retrospectivos , Apneia Obstrutiva do Sono/cirurgia , Tempo para o Tratamento , Estados Unidos
3.
Anal Bioanal Chem ; 413(27): 6747-6767, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34686897

RESUMO

Many voltammetry methods have been developed to monitor brain extracellular dopamine levels. Fewer approaches have been successful in detecting serotonin in vivo. No voltammetric techniques are currently available to monitor both neurotransmitters simultaneously across timescales, even though they play integrated roles in modulating behavior. We provide proof-of-concept for rapid pulse voltammetry coupled with partial least squares regression (RPV-PLSR), an approach adapted from multi-electrode systems (i.e., electronic tongues) used to identify multiple components in complex environments. We exploited small differences in analyte redox profiles to select pulse steps for RPV waveforms. Using an intentionally designed pulse strategy combined with custom instrumentation and analysis software, we monitored basal and stimulated levels of dopamine and serotonin. In addition to faradaic currents, capacitive currents were important factors in analyte identification arguing against background subtraction. Compared to fast-scan cyclic voltammetry-principal components regression (FSCV-PCR), RPV-PLSR better differentiated and quantified basal and stimulated dopamine and serotonin associated with striatal recording electrode position, optical stimulation frequency, and serotonin reuptake inhibition. The RPV-PLSR approach can be generalized to other electrochemically active neurotransmitters and provides a feedback pipeline for future optimization of multi-analyte, fit-for-purpose waveforms and machine learning approaches to data analysis.


Assuntos
Encéfalo/metabolismo , Dopamina/análise , Técnicas Eletroquímicas/métodos , Serotonina/análise , Animais , Encéfalo/efeitos dos fármacos , Calibragem , Fibra de Carbono , Dopamina/farmacocinética , Técnicas Eletroquímicas/instrumentação , Técnicas Eletroquímicas/estatística & dados numéricos , Escitalopram/farmacologia , Feminino , Análise dos Mínimos Quadrados , Aprendizado de Máquina , Camundongos Endogâmicos C57BL , Microeletrodos , Neurotransmissores/análise , Serotonina/farmacocinética , Inibidores Seletivos de Recaptação de Serotonina/farmacologia , Processamento de Sinais Assistido por Computador , Software
4.
Risk Anal ; 41(7): 1204-1212, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33960513

RESUMO

This article describes an interdisciplinary community resilience research project and presents a case study that supports bringing researchers together before a disaster to develop plans, procedures, and preapproved Institutional Review Board (IRB) protocols. In addition, this article explains how researchers from various academic institutions and their federal agency partners can effectively collaborate by creating an IRB Authorization Agreement (IAA). Such preparations can support interdisciplinary rapid response disaster fieldwork that is timely, ethically informed, and scientifically rigorous. This fieldwork preplanning process can also advance interdisciplinary team formation and data collection efforts over the long term.


Assuntos
Planejamento em Desastres/organização & administração , Comitês de Ética em Pesquisa , Pesquisa Interdisciplinar/organização & administração , Pesquisadores , Humanos , Estudos de Casos Organizacionais
5.
Nano Lett ; 20(8): 5982-5990, 2020 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-32706969

RESUMO

We detect short oligonucleotides and distinguish between sequences that differ by a single base, using label-free, electronic field-effect transistors (FETs). Our sensing platform utilizes ultrathin-film indium oxide FETs chemically functionalized with single-stranded DNA (ssDNA). The ssDNA-functionalized semiconducting channels in FETs detect fully complementary DNA sequences and differentiate these sequences from those having different types and locations of single base-pair mismatches. Changes in charge associated with surface-bound ssDNA vs double-stranded DNA (dsDNA) alter FET channel conductance to enable detection due to differences in DNA duplex stability. We illustrate the capability of ssDNA-FETs to detect complementary RNA sequences and to distinguish from RNA sequences with single nucleotide variations. The development and implementation of electronic biosensors that rapidly and sensitively detect and differentiate oligonucleotides present new opportunities in the fields of disease diagnostics and precision medicine.


Assuntos
Técnicas Biossensoriais , Transistores Eletrônicos , Pareamento Incorreto de Bases , DNA/genética , DNA de Cadeia Simples/genética , Nucleotídeos , RNA
6.
Nano Lett ; 20(3): 1747-1754, 2020 03 11.
Artigo em Inglês | MEDLINE | ID: mdl-32027140

RESUMO

Plasmonic nanostructures have a wide range of applications, including chemical and biological sensing. However, the development of techniques to fabricate submicrometer-sized plasmonic structures over large scales remains challenging. We demonstrate a high-throughput, cost-effective approach to fabricate Au nanoribbons via chemical lift-off lithography (CLL). Commercial HD-DVDs were used as large-area templates for CLL. Transparent glass slides were coated with Au/Ti films and functionalized with self-assembled alkanethiolate monolayers. Monolayers were patterned with lines via CLL. The lifted-off, exposed regions of underlying Au were selectively etched into large-area grating-like patterns (200 nm line width; 400 nm pitch; 60 nm height). After removal of the remaining monolayers, a thin In2O3 layer was deposited and the resulting gratings were used as plasmonic sensors. Distinct features in the extinction spectra varied in their responses to refractive index changes in the solution environment with a maximum bulk sensitivity of ∼510 nm/refractive index unit. Sensitivity to local refractive index changes in the near-field was also achieved, as evidenced by real-time tracking of lipid vesicle or protein adsorption. These findings show how CLL provides a simple and economical means to pattern large-area plasmonic nanostructures for applications in optoelectronics and sensing.


Assuntos
Ouro/química , Índio/química , Nanopartículas Metálicas/química , Nanotubos de Carbono/química , Ressonância de Plasmônio de Superfície
7.
J Neurosci ; 39(21): 4162-4178, 2019 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-30862664

RESUMO

Pain is a multidimensional experience and negative affect, or how much the pain is "bothersome", significantly impacts the sufferers' quality of life. It is well established that the κ opioid system contributes to depressive and dysphoric states, but whether this system contributes to the negative affect precipitated by the occurrence of chronic pain remains tenuous. Using a model of persistent pain, we show by quantitative real-time-PCR, florescence in situ hybridization, Western blotting and GTPgS autoradiography an upregulation of expression and the function of κ opioid receptors (KORs) and its endogenous ligand dynorphin in the mesolimbic circuitry in animals with chronic pain compared with surgical controls. Using in vivo microdialysis and microinjection of drugs into the mesolimbic dopamine system, we demonstrate that inhibiting KORs reinstates evoked dopamine release and reward-related behaviors in chronic pain animals. Chronic pain enhanced KOR agonist-induced place aversion in a sex-dependent manner. Using various place preference paradigms, we show that activation of KORs drives pain aversive states in male but not female mice. However, KOR antagonist treatment was effective in alleviating anxiogenic and depressive affective-like behaviors in both sexes. Finally, ablation of KORs from dopamine neurons using AAV-TH-cre in KORloxP mice prevented pain-induced aversive states as measured by place aversion assays. Our results strongly support the use of KOR antagonists as therapeutic adjuvants to alleviate the emotional, tonic-aversive component of chronic pain, which is argued to be the most significant component of the pain experience that impacts patients' quality of life.SIGNIFICANCE STATEMENT We show that KORs are sufficient to drive the tonic-aversive component of chronic pain; the emotional component of pain that is argued to significantly impact a patient's quality of life. The impact of our study is broadly relevant to affective disorders associated with disruption of reward circuitry and thus likely contributes to many of the devastating sequelae of chronic pain, including the poor response to treatment of many patients, debilitating affective disorders (other disorders including anxiety and depression that demonstrate high comorbidity with chronic pain) and substance abuse. Indeed, coexisting psychopathology increases pain intensity, pain-related disability and effectiveness of treatments (Jamison and Edwards, 2013).


Assuntos
Dor Crônica/metabolismo , Dor Crônica/psicologia , Emoções/fisiologia , Percepção da Dor/fisiologia , Receptores Opioides kappa/metabolismo , Animais , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Ratos , Ratos Long-Evans
8.
Public Health Nutr ; 22(15): 2766-2776, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31221240

RESUMO

OBJECTIVE: To explore the perceptions of soldiers participating in a US Army Office of The Surgeon General's worksite health promotion programme (WHPP) on the local food environment within their campus-style workplace. DESIGN: Focus groups were conducted to evaluate the perceived effectiveness of the WHPP implementation. Further exploration of focus group data through thematic analysis focused on perceived contributions of the military campus-style food environment to soldiers' nutrition behaviours. SETTING: Three US Army installations located in the continental USA. PARTICIPANTS: Active duty soldiers (n 366) participating in one of the fifty-eight focus groups. RESULTS: Soldiers shared a common belief of self-discipline and personal responsibility as the foothold to nutrition behaviour change. Soldiers described aspects of the military campus-style food environment as factors impeding achievement of optimal nutrition. Collectively, soldiers perceived the proximity and density of fast-food restaurants, lack of healthy alternatives on the installation and the cost of healthy food as inhibitors to choosing healthy foods. Overwhelmingly, soldiers also perceived time constraints as a factor contributing to unhealthy food choices. CONCLUSIONS: Although nutrition behaviour is individually driven, soldiers perceived the military campus-style food environment inhibits healthy decision making. Nutrition programming in military WHPP must integrate food environment changes to improve soldiers' nutrition behaviour outcomes. Applicable to the military, food choice behaviour studies suggest environmental changes must be appealing to young adults. Considerations for environmental changes should include an increased portion size for healthy options, broadened use of soldiers' daily food allowances on local produce and increased availability of grab-and-go options.


Assuntos
Comportamento Alimentar/psicologia , Promoção da Saúde/métodos , Militares/psicologia , Local de Trabalho/psicologia , Comportamento de Escolha , Feminino , Grupos Focais , Humanos , Masculino , Percepção , Avaliação de Programas e Projetos de Saúde , Estados Unidos , Adulto Jovem
9.
Nano Lett ; 18(9): 5590-5595, 2018 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-30060654

RESUMO

Nanoribbon- and nanowire-based field-effect transistors (FETs) have attracted significant attention due to their high surface-to-volume ratios, which make them effective as chemical and biological sensors. However, the conventional nanofabrication of these devices is challenging and costly, posing a major barrier to widespread use. We report a high-throughput approach for producing arrays of ultrathin (∼3 nm) In2O3 nanoribbon FETs at the wafer scale. Uniform films of semiconducting In2O3 were prepared on Si/SiO2 surfaces via a sol-gel process prior to depositing Au/Ti metal layers. Commercially available high-definition digital versatile discs were employed as low-cost, large-area templates to prepare polymeric stamps for chemical lift-off lithography, which selectively removed molecules from self-assembled monolayers functionalizing the outermost Au surfaces. Nanoscale chemical patterns, consisting of one-dimensional lines (200 nm wide and 400 nm pitch) extending over centimeter length scales, were etched into the metal layers using the remaining monolayer regions as resists. Subsequent etch processes transferred the patterns into the underlying In2O3 films before the removal of the protective organic and metal coatings, revealing large-area nanoribbon arrays. We employed nanoribbons in semiconducting FET channels, achieving current on-to-off ratios over 107 and carrier mobilities up to 13.7 cm2 V-1 s-1. Nanofabricated structures, such as In2O3 nanoribbons and others, will be useful in nanoelectronics and biosensors. The technique demonstrated here will enable these applications and expand low-cost, large-area patterning strategies to enable a variety of materials and design geometries in nanoelectronics.


Assuntos
Índio/química , Nanotecnologia/métodos , Nanotubos de Carbono/química , Semicondutores , Técnicas Biossensoriais/instrumentação , Desenho de Equipamento , Ouro/química , Nanotecnologia/economia , Nanotecnologia/instrumentação , Nanotubos de Carbono/ultraestrutura , Dióxido de Silício/química , Titânio/química
10.
Nano Lett ; 17(8): 5035-5042, 2017 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-28737930

RESUMO

We report a facile, high-throughput soft lithography process that utilizes nanoscale channels formed naturally at the edges of microscale relief features on soft, elastomeric stamps. Upon contact with self-assembled monolayer (SAM) functionalized substrates, the roof of the stamp collapses, resulting in the selective removal of SAM molecules via a chemical lift-off process. With this technique, which we call self-collapse lithography (SCL), sub-30 nm patterns were achieved readily using masters with microscale features prepared by conventional photolithography. The feature sizes of the chemical patterns can be varied continuously from ∼2 µm to below 30 nm by decreasing stamp relief heights from 1 µm to 50 nm. Likewise, for fixed relief heights, reducing the stamp Young's modulus from ∼2.0 to ∼0.8 MPa resulted in shrinking the features of resulting patterns from ∼400 to ∼100 nm. The self-collapse mechanism was studied using finite element simulation methods to model the competition between adhesion and restoring stresses during patterning. These results correlate well with the experimental data and reveal the relationship between the line widths, channel heights, and Young's moduli of the stamps. In addition, SCL was applied to pattern two-dimensional arrays of circles and squares. These chemical patterns served as resists during etching processes to transfer patterns to the underlying materials (e.g., gold nanostructures). This work provides new insights into the natural propensity of elastomeric stamps to self-collapse and demonstrates a means of exploiting this behavior to achieve patterning via nanoscale chemical lift-off lithography.

11.
Nano Lett ; 17(5): 3302-3311, 2017 05 10.
Artigo em Inglês | MEDLINE | ID: mdl-28409640

RESUMO

We designed and fabricated large arrays of polymer pens having sub-20 nm tips to perform chemical lift-off lithography (CLL). As such, we developed a hybrid patterning strategy called polymer-pen chemical lift-off lithography (PPCLL). We demonstrated PPCLL patterning using pyramidal and v-shaped polymer-pen arrays. Associated simulations revealed a nanometer-scale quadratic relationship between contact line widths of the polymer pens and two other variables: polymer-pen base line widths and vertical compression distances. We devised a stamp support system consisting of interspersed arrays of flat-tipped polymer pens that are taller than all other sharp-tipped polymer pens. These supports partially or fully offset stamp weights thereby also serving as a leveling system. We investigated a series of v-shaped polymer pens with known height differences to control relative vertical positions of each polymer pen precisely at the sub-20 nm scale mimicking a high-precision scanning stage. In doing so, we obtained linear-array patterns of alkanethiols with sub-50 nm to sub-500 nm line widths and minimum sub-20 nm line width tunable increments. The CLL pattern line widths were in agreement with those predicted by simulations. Our results suggest that through informed design of a stamp support system and tuning of polymer-pen base widths, throughput can be increased by eliminating the need for a scanning stage system in PPCLL without sacrificing precision. To demonstrate functional microarrays patterned by PPCLL, we inserted probe DNA into PPCLL patterns and observed hybridization by complementary target sequences.

12.
Acc Chem Res ; 49(8): 1449-57, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27064348

RESUMO

We discuss the origins, motivation, invention, development, applications, and future of chemical lift-off lithography, in which a specified pattern of a self-assembled monolayer is removed, i.e., lifted off, using a reactive, patterned stamp that is brought into contact with the monolayer. For Au substrates, this process produces a supported, patterned monolayer of Au on the stamp in addition to the negative pattern in the original molecular monolayer. Both the patterned molecular monolayer on the original substrate and the patterned supported metal monolayer on the stamp are useful as materials and for further applications in sensing and other areas. Chemical lift-off lithography effectively lowers the barriers to and costs of high-resolution, large-area nanopatterning. On the patterned monolayer side, features in the single-nanometer range can be produced across large (square millimeter or larger) areas. Patterns smaller than the original stamp feature sizes can be produced by controlling the degree of contact between the stamp and the lifted-off monolayer. We note that this process is different than conventional lift-off processes in lithography in that chemical lift-off lithography removes material, whereas conventional lift-off is a positive-tone patterning method. Chemical lift-off lithography is in some ways similar to microtransfer printing. Chemical lift-off lithography has critical advantages in the preparation of biocapture surfaces because the molecules left behind are exploited to space and to orient functional(ized) molecules. On the supported metal monolayer side, a new two-dimensional material has been produced. The useful important chemical properties of Au (vis-à-vis functionalization with thiols) are retained, but the electronic and optical properties of bulk Au or even Au nanoparticles are not. These metal monolayers do not quench excitation and may be useful in optical measurements, particularly in combination with selective binding due to attached molecular recognition elements. In contrast to materials such as graphene that have bonding confined to two dimensions, these metal monolayers can be straightforwardly patterned-by patterning the stamp, the initial monolayer, or the initial substrate. Well-developed thiol-Au and related chemistries can be used on the supported monolayers. As there is little quenching and photoabsorption, spectroscopic imaging methods can be used on these functionalized materials. We anticipate that the properties of the metal monolayers can be tuned by varying the chemical, physical, and electronic connections made by and to the supporting molecular layers. That is, the amount of charge in the layer can be determined by controlling the density of S-Au (or other) connections and the molecular backbone and functionality, which determine the strength with which the chemical contact withdraws charge from the metal. This process should work for other coinage-metal substrates and additional systems where the binding of the outermost layers to the substrate is weaker than the molecule-substrate attachment.

13.
Int Urogynecol J ; 27(10): 1507-12, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27037561

RESUMO

INTRODUCTION AND HYPOTHESIS: Urinary incontinence (UI) and pelvic organ prolapse (POP) occur in 30-50 % of women. It is proposed that increases in intra-abdominal pressure (IAP) caused by high-intensity activities may contribute to symptoms of pelvic floor dysfunction. There is a lack of consensus as to the type of activity restrictions that may be necessary in this population. The objective was to determine the change in IAP (cm H20) during abdominal curl and cough in patients with UI and POP attending urodynamic evaluation. METHODS: In this exploratory descriptive study, 30 women with diagnosed POP and/or UI were recruited. IAP was measured by multichannel cystometry whilst participants performed three abdominal curls and three maximal coughs. RESULTS: Participants were aged 29-80 (mean 56.2) years, and mean ± standard deviation (SD) body mass index (BMI) was 29.9 (5.2) kg/m(-2). All participants had UI and 12 had POP in addition to UI. IAP increased significantly from rest to abdominal curl and cough (19.6-50.3 and 78.4, respectively; p < 0.001). Greater pressures were generated in the women with POP than in those with UI only (p = 0.02). There were large variations in change in pressure between participants (1.67-159.66 for cough; 4-81.67 for abdominal curl). CONCLUSION: The large variability in IAP generated during abdominal curl and cough suggests some current recommendations may be unnecessarily restrictive in some women but important in others. Advice for women with pelvic floor dysfunction undertaking tasks that increase IAP needs to be individualized.


Assuntos
Músculos Abdominais/fisiopatologia , Exercício Físico/fisiologia , Prolapso de Órgão Pélvico/fisiopatologia , Pressão , Incontinência Urinária/fisiopatologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Índice de Massa Corporal , Tosse , Feminino , Humanos , Pessoa de Meia-Idade
14.
Am J Bioeth ; 16(8): 30-7, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27366845

RESUMO

Institutional review board (IRB) delays may hinder the successful completion of federally funded research in the U.S. military. When this happens, time-sensitive, mission-relevant questions go unanswered. Research participants face unnecessary burdens and risks if delays squeeze recruitment timelines, resulting in inadequate sample sizes for definitive analyses. More broadly, military members are exposed to untested or undertested interventions, implemented by well-intentioned leaders who bypass the research process altogether. To illustrate, we offer two case examples. We posit that IRB delays often appear in the service of managing institutional risk, rather than protecting research participants. Regulators may see more risk associated with moving quickly than risk related to delay, choosing to err on the side of bureaucracy. The authors of this article, all of whom are military-funded researchers, government stakeholders, and/or human subject protection experts, offer feasible recommendations to improve the IRB system and, ultimately, research within military, veteran, and civilian populations.


Assuntos
Comitês de Ética em Pesquisa , Medicina Militar , Militares , Ética em Pesquisa , Humanos , Pesquisadores , Risco
15.
J Undergrad Neurosci Educ ; 15(1): A5-A10, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27980464

RESUMO

Neuroscience doctoral students must master specific laboratory techniques and approaches to complete their thesis work (hands-on learning). Due to the highly interdisciplinary nature of the field, learning about a diverse range of methodologies through literature surveys and coursework is also necessary for student success (hands-off learning). Traditional neuroscience coursework stresses what is known about the nervous system with relatively little emphasis on the details of the methods used to obtain this knowledge. Furthermore, hands-off learning is made difficult by a lack of detail in methods sections of primary articles, subfield-specific jargon and vague experimental rationales. We designed a student-taught course to enable first-year neuroscience doctoral students to overcome difficulties in hands-off learning by introducing a new approach to reading and presenting primary research articles that focuses on methodology. In our literature-based course students were encouraged to present a method with which they had no previous experience. To facilitate weekly discussions, "experts" were invited to class sessions. Experts were advanced graduate students who had hands-on experience with the method being covered and served as discussion co-leaders. Self-evaluation worksheets were administered on the first and last days of the 10-week course and used to assess students' confidence in discussing research and methods outside of their primary research expertise. These evaluations revealed that the course significantly increased the students' confidence in reading, presenting and discussing a wide range of advanced neuroscience methods.

16.
J Neurochem ; 130(6): 748-58, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24899127

RESUMO

Human TPH2 (hTPH2) catalyzes the rate-limiting step in CNS serotonin biosynthesis. We characterized a single-nucleotide polymorphism (C2755A) in the hTPH2 gene that substitutes tyrosine for serine at position 41 in the regulatory domain of the enzyme. This polymorphism is associated with bipolar disorder and peripartum depression in a Chinese population. Recombinant h TPH2 human proteins were expressed in bacteria and also stably expressed in PC12 cells. Following bacterial expression and purification, the tyrosine for serine substitution at position 41 (S41Y) polymorphic enzyme displayed increased Vmax with unchanged Km values. By contrast, enzyme stability was decreased in vitro from 32 min to 4 min (37 °C) for the S41Y enzyme (as compared to the wild-type enzyme). The S41Y polymorphism decreased cyclic AMP-dependent protein kinase A-mediated phosphorylation ~ 50% relative to wild-type hTPH2, suggesting that the S41Y mutation may disrupt the post-translational regulation of this enzyme. Transfected PC12 cells expressed hTPH2 mRNA, active protein, and synthesized and released serotonin. Paradoxically, while S41Y-transfected PC12 cells expressed higher levels of hTPH2 than wild type, they synthesized less serotonin. These findings suggest a modified regulation of the S41Y gene variant leading to altered regulation and reduced neurotransmitter synthesis that may contribute to association of the polymorphism with bipolar disorder and depression. We report the functional implications of a polymorphic human tryptophan hydroxylase-2 gene associated with depression and bipolar disorder. The polymorphic enzyme (serine-41 converted to tyrosine) has increased activity, but decreased enzyme stability and serotonin production. Moreover, cyclic AMP-dependent protein kinase (PKA)-mediated phosphorylation of the mutant enzyme is decreased suggesting modified regulation of the S41Y variant leading to altered serotonin.


Assuntos
Triptofano Hidroxilase/genética , Animais , Clonagem Molecular , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Dopamina/metabolismo , Doxiciclina/farmacologia , Eletroforese em Gel de Poliacrilamida , Escherichia coli/metabolismo , Humanos , Cinética , Mutação/genética , Mutação/fisiologia , Células PC12 , Fosforilação , Polimorfismo Genético/genética , Polimorfismo de Nucleotídeo Único , Ratos , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Serotonina/biossíntese , Temperatura , Triptofano Hidroxilase/química
17.
Chem Soc Rev ; 42(7): 2725-45, 2013 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-23258565

RESUMO

Self-assembled monolayers are a unique class of nanostructured materials, with properties determined by their molecular lattice structures, as well as the interfaces with their substrates and environments. As with other nanostructured materials, defects and dimensionality play important roles in the physical, chemical, and biological properties of the monolayers. In this review, we discuss monolayer structures ranging from surfaces (two-dimensional) down to single molecules (zero-dimensional), with a focus on applications of each type of structure, and on techniques that enable characterization of monolayer physical properties down to the single-molecule scale.


Assuntos
Nanoestruturas/química , Grafite/química , Ligação de Hidrogênio , Polimerização , Semicondutores , Propriedades de Superfície
18.
Mov Disord ; 28(9): 1263-70, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23630162

RESUMO

To evaluate the hypothesis that functionally over-expressing alleles of the serotonin transporter (SERT) gene (solute carrier family 6, member 4, SLC6A4) are present in Tourette's disorder (TD), just as we previously observed in obsessive compulsive disorder (OCD), we evaluated TD probands (N = 151) and controls (N = 858). We genotyped the refined SERT-linked polymorphic region 5-HTTLPR/rs25531 and the associated rs25532 variant in the SLC6A4 promoter plus the rare coding variant SERT isoleucine-to-valine at position 425 (I425V). The higher expressing 5-HTTLPR/rs25531 LA allele was more prevalent in TD probands than in controls (χ(2) = 5.75; P = 0.017; odds ratio [OR], 1.35); and, in a secondary analysis, surprisingly, it was significantly more frequent in probands who had TD alone than in those who had TD plus OCD (Fisher's exact test; P = 0.0006; OR, 2.29). Likewise, the higher expressing LAC haplotype (5-HTTLPR/rs25531/rs25532) was more frequent in TD probands than in controls (P = 0.024; OR, 1.33) and also in the TD alone group versus the TD plus OCD group (P = 0.0013; OR, 2.14). Furthermore, the rare gain-of-function SERT I425V variant was observed in 3 male siblings with TD and/or OCD and in their father. Thus, the cumulative count of SERT I425V becomes 1.57% in OCD/TD spectrum conditions versus 0.15% in controls, with a recalculated, family-adjusted significance of χ(2) = 15.03 (P < 0.0001; OR, 9.0; total worldwide genotyped, 2914). This report provides a unique combination of common and rare variants in one gene in TD, all of which are associated with SERT gain of function. Thus, altered SERT activity represents a potential contributor to serotonergic abnormalities in TD. The present results call for replication in a similarly intensively evaluated sample. © 2013 Movement Disorder Society.


Assuntos
Predisposição Genética para Doença/genética , Polimorfismo de Nucleotídeo Único/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Síndrome de Tourette/genética , Feminino , Frequência do Gene , Estudos de Associação Genética , Genótipo , Humanos , Masculino , Transtorno Obsessivo-Compulsivo/genética , Escalas de Graduação Psiquiátrica
19.
Pediatr Crit Care Med ; 14(5): e218-24, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23439467

RESUMO

BACKGROUND AND OBJECTIVES: Evaluate risk factors for and impact of acute kidney injury on children following the arterial switch operation. DESIGN: Single-center retrospective chart review. SETTING: A tertiary children's hospital. PATIENTS: A total of 92 patients receiving the arterial switch operation from 1997 to 2008 at severe acute kidney injury was defined as a 100% serum creatinine rise over baseline. RESULTS: Of 92 patients, 18 (20%) developed severe acute kidney injury. Neither patient age or weight nor cardiopulmonary bypass time correlated with the development of acute kidney injury. Acute kidney injury was associated with the following: higher postoperative day 1 (POD1) fluid balance, higher inotrope scores (POD1 and POD2), and longer: postoperative ICU length of stay (p = 0.005), overall ICU length of stay (p = 0.05), and postoperative hospital length of stay (p = 0.006). The time to peak creatinine for acute kidney injury patients was between POD1 and POD2. Correction of serum creatinine for fluid balance increased the population defined as severe acute kidney injury and strengthened the association of acute kidney injury with postoperative morbidity. CONCLUSIONS: Acute kidney injury following the arterial switch operation is associated with increased morbidity. In this single center, single population, and homogenous cohort of patients, the development of acute kidney injury was not correlated with age, size, or cardiopulmonary bypass time, but was still associated with prolonged duration of ventilation and hospitalization. Notably, the failure to correct serum creatinine for fluid balance underestimates the prevalence and impact of acute kidney injury.


Assuntos
Injúria Renal Aguda/etiologia , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ponte Cardiopulmonar/efeitos adversos , Creatina/sangue , Complicações Pós-Operatórias/sangue , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/mortalidade , Análise de Variância , Procedimentos Cirúrgicos Cardíacos/métodos , Procedimentos Cirúrgicos Cardíacos/mortalidade , Ponte Cardiopulmonar/mortalidade , Feminino , Mortalidade Hospitalar , Humanos , Recém-Nascido , Tempo de Internação , Masculino , Morbidade , Estudos Retrospectivos
20.
Food Drug Law J ; 68(4): 329-56, i, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24552078

RESUMO

FDA's proposed graphic warning labels for cigarette packages have been scrutinized for potentially violating the First Amendment's free speech clause. This article addresses the distinction between the commercial speech and compelled speech doctrines and their applicability in analyzing the constitutionality of the labels. The government's position is that the labels evoke an emotional response and educate consumers, while tobacco companies argue that the labels forcibly promote the government's message. Two federal appellate courts, applying different legal standards, have arrived at different conclusions. This article advocates that the Supreme Court, if faced with review of the labels, should apply strict scrutiny and declare the labels unconstitutional.


Assuntos
Rotulagem de Produtos/legislação & jurisprudência , Embalagem de Produtos/legislação & jurisprudência , Indústria do Tabaco/legislação & jurisprudência , Humanos , Prevenção do Hábito de Fumar , Estados Unidos , United States Food and Drug Administration
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