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1.
Aerosol Sci Technol ; 49(8): 599-610, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26412929

RESUMO

Epidemiological studies have shown that exposure to airborne particulate matter can be an important risk factor for some common respiratory diseases. While many studies have shown that particulate matter exposures are associated with inflammatory reactions, the role of specific cellular responses in the manifestation of primary hypersensitivities, and the progression of respiratory diseases remains unclear. In order to better understand mechanisms by which particulate matter can exert adverse health effects, more robust approaches to support in vitro studies are warranted. In response to this need, a group of accepted toxicology assays were adapted to create an analytical suite for screening and evaluating the effects of important, ubiquitous atmospheric pollutants on two model human lung cell lines (epithelial and immature macrophage). To demonstrate the utility of this suite, responses to intact diesel exhaust particles, and mass-based equivalent doses of their organic extracts were examined. Results suggest that extracts have the potential to induce greater biological responses than those associated with their colloidal counterpart. Additionally, macrophage cells appear to be more susceptible to the cytotoxic effects of both intact diesel exhaust particles and their organic extract, than epithelial cells tested in parallel. As designed, the suite provided a more robust basis for characterizing toxicity mechanisms than the analysis of any individual assay. Findings suggest that cellular responses to particulate matter are cell line dependent, and show that the collection and preparation of PM and/or their extracts have the potential to impact cellular responses relevant to screening fundamental elements of respiratory toxicity.

4.
PLoS One ; 8(6): e68884, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23922638

RESUMO

The ability to initiate and sustain trust is critical to health and well-being. Willingness to trust is in part determined by the reputation of the putative trustee, gained via direct interactions or indirectly through word of mouth. Few studies have examined how the reputation of others is instantiated in the brain during trust decisions. Here we use an event-related functional MRI (fMRI) design to examine what neural signals correspond to experimentally manipulated reputations acquired in direct interactions during trust decisions. We hypothesized that the caudate (dorsal striatum) and putamen (ventral striatum) and amygdala would signal differential reputations during decision-making. Twenty-nine healthy adults underwent fMRI scanning while completing an iterated Trust Game as trusters with three fictive trustee partners who had different tendencies to reciprocate (i.e., likelihood of rewarding the truster), which were learned over multiple exchanges with real-time feedback. We show that the caudate (both left and right) signals reputation during trust decisions, such that caudate is more active to partners with two types of "bad" reputations, either indifferent partners (who reciprocate 50% of the time) or unfair partners (who reciprocate 25% of the time), than to those with "good" reputations (who reciprocate 75% of the time). Further, individual differences in caudate activity related to biases in trusting behavior in the most uncertain situation, i.e. when facing an indifferent partner. We also report on other areas that were activated by reputation at p < 0.05 whole brain corrected. Our findings suggest that the caudate is involved in signaling and integrating reputations gained through experience into trust decisions, demonstrating a neural basis for this key social process.


Assuntos
Tonsila do Cerebelo/fisiologia , Gânglios da Base/fisiologia , Tomada de Decisões , Confiança , Adulto , Feminino , Neuroimagem Funcional , Jogos Experimentais , Humanos , Imageamento por Ressonância Magnética
5.
Depress Anxiety ; 30(4): 353-61, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23576237

RESUMO

OBJECTIVE: Generalized social anxiety disorder (GSAD) is characterized by excessive fear of public scrutiny and reticence in social engagement. Previous studies have probed the neural basis of GSAD often using static, noninteractive stimuli (e.g., face photographs) and have identified dysfunction in fear circuitry. We sought to investigate brain-based dysfunction in GSAD during more real-world, dynamic social interactions, focusing on the role of reward-related regions that are implicated in social decision-making. METHODS: Thirty-six healthy individuals (healthy control [HC]) and 36 individuals with GSAD underwent functional magnetic resonance imaging (fMRI) scanning while participating in a behavioral economic game ("Trust Game") involving iterative exchanges with fictive partners who acquire differential reputations for reciprocity. We investigated brain responses to reciprocation of trust in one's social partner, and how these brain responses are modulated by partner reputation for repayment. RESULTS: In both HC and GSAD, receipt of reciprocity robustly engaged ventral striatum, a region implicated in reward. In HC, striatal responses to reciprocity were specific to partners who have consistently returned the investment ("cooperative partners"), and were absent for partners who lack a cooperative reputation. In GSAD, modulation of striatal responses by partner reputation was absent. Social anxiety severity predicted diminished responses to cooperative partners. CONCLUSION: These results suggest abnormalities in GSAD in reward-related striatal mechanisms that may be important for the initiation, valuation, and maintenance of cooperative social relationships. Moreover, this study demonstrates that dynamic, interactive task paradigms derived from economics can help illuminate novel mechanisms of pathology in psychiatric illnesses in which social dysfunction is a cardinal feature.


Assuntos
Gânglios da Base/fisiopatologia , Comportamento Cooperativo , Relações Interpessoais , Transtornos Fóbicos/fisiopatologia , Adulto , Gânglios da Base/fisiologia , Mapeamento Encefálico , Estudos de Casos e Controles , Feminino , Neuroimagem Funcional , Humanos , Imageamento por Ressonância Magnética , Masculino , Recompensa , Confiança , Adulto Jovem
6.
J Microbiol Methods ; 92(1): 11-3, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23373071

RESUMO

The diversity of applications utilizing antimicrobial laden textiles continues to grow, yet testing methods based on the liquid loading of cultures to challenge textiles remain unchanged. For bioaerosol applications, liquid challenge methods are unsuitable. We present a method of aerosol based loading and microbial recovery for contextual testing antimicrobial textiles.


Assuntos
Desinfetantes/farmacologia , Desinfecção/métodos , Têxteis/microbiologia , Aerossóis/administração & dosagem , Bactérias/efeitos dos fármacos , Filtração/métodos
7.
Soc Cogn Affect Neurosci ; 8(5): 494-8, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22368214

RESUMO

The neuropeptide oxytocin functions as a hormone and neurotransmitter and facilitates complex social cognition and approach behavior. Given that empathy is an essential ingredient for third-party decision-making in institutions of justice, we investigated whether exogenous oxytocin modulates empathy of an unaffected third-party toward offenders and victims of criminal offenses. Healthy male participants received intranasal oxytocin or placebo in a randomized, double-blind, placebo-controlled, between-subjects design. Participants were given a set of legal vignettes that described an event during which an offender engaged in criminal offenses against victims. As an unaffected third-party, participants were asked to rate those criminal offenses on the degree to which the offender deserved punishment and how much harm was inflicted on the victim. Exogenous oxytocin selectively increased third-party decision-makers' perceptions of harm for victims but not the desire to punish offenders of criminal offenses. We argue that oxytocin promoted empathic concern for the victim, which in turn increased the tendency for prosocial approach behavior regarding the interpersonal relationship between an unaffected third-party and a fictional victim in the criminal scenarios. Future research should explore the context- and person-dependent nature of exogenous oxytocin in individuals with antisocial personality disorder and psychopathy, in whom deficits in empathy feature prominently.


Assuntos
Transtorno da Personalidade Antissocial/metabolismo , Transtorno da Personalidade Antissocial/fisiopatologia , Vítimas de Crime , Criminosos , Empatia/efeitos dos fármacos , Ocitocina/farmacologia , Adolescente , Adulto , Análise de Variância , Vítimas de Crime/psicologia , Criminosos/psicologia , Tomada de Decisões/efeitos dos fármacos , Método Duplo-Cego , Humanos , Masculino , Testes Psicológicos , Autorrelato , Adulto Jovem
8.
Front Hum Neurosci ; 6: 4, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22347177

RESUMO

Given that human trust behavior is heritable and intranasal administration of oxytocin enhances trust, the oxytocin receptor (OXTR) gene is an excellent candidate to investigate genetic contributions to individual variations in trust behavior. Although a single-nucleotide polymorphism involving an adenine (A)/guanine (G) transition (rs53576) has been associated with socio-emotional phenotypes, its link to trust behavior is unclear. We combined genotyping of healthy male students (n = 108) with the administration of a trust game experiment. Our results show that a common occurring genetic variation (rs53576) in the OXTR gene is reliably associated with trust behavior rather than a general increase in trustworthy or risk behaviors. Individuals homozygous for the G allele (GG) showed higher trust behavior than individuals with A allele carriers (AA/AG). Although the molecular functionality of this polymorphism is still unknown, future research should clarify how the OXTR gene interacts with other genes and the environment in promoting socio-emotional behaviors.

9.
Bioelectromagnetics ; 31(8): 649-55, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20830734

RESUMO

Small alterations in static magnetic fields have been shown to affect certain chemical reaction rates ex vivo. In this manuscript, we present data demonstrating that similar small changes in static magnetic fields between individual cell culture incubators results in significantly altered cell cycle rates for multiple cancer-derived cell lines. This change as assessed by cell number is not a result of apoptosis, necrosis, or cell cycle alterations. While the underlying mechanism is unclear, the implications for all cell culture experiments are clear; static magnetic field conditions within incubators must be considered and/or controlled just as one does for temperature, humidity, and carbon dioxide concentration.


Assuntos
Planeta Terra , Magnetismo , Técnicas de Cultura de Células , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Fatores de Tempo
10.
Proc Natl Acad Sci U S A ; 107(29): 13099-104, 2010 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-20615982

RESUMO

Brain reward circuitry, including ventral striatum and orbitofrontal cortex, has been independently implicated in preferences for fair and cooperative outcomes as well as learning of reputations. Using functional MRI (fMRI) and a "trust game" task involving iterative exchanges with fictive partners who acquire different reputations for reciprocity, we measured brain responses in 36 healthy adults when positive actions (entrust investment to partners) yield positive returns (reciprocity) and how these brain responses are modulated by partner reputation for repayment. Here we show that positive reciprocity robustly engages the ventral striatum and orbitofrontal cortex. Moreover, this signal of reciprocity in the ventral striatum appears selectively in response to partners who have consistently returned the investment (e.g., a reputation for reciprocity) and is absent for partners who lack a reputation for reciprocity. These findings elucidate a fundamental brain mechanism, via reward-related neural substrates, by which human cooperative relationships are initiated and sustained.


Assuntos
Gânglios da Base/fisiologia , Encéfalo/fisiologia , Relações Interpessoais , Recompensa , Adulto , Mapeamento Encefálico , Comportamento de Escolha , Comportamento Cooperativo , Árvores de Decisões , Retroalimentação Psicológica , Feminino , Humanos , Masculino , Confiança
11.
Pediatr Res ; 67(5): 469-75, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20139796

RESUMO

Conventional temperature measurements rely on material responses to heat, which can be detected visually. When Galileo developed an air expansion based device to detect temperature changes, Santorio, a contemporary physician, added a scale to create the first thermometer. With this instrument, patients' temperatures could be measured, recorded, and related to changing health conditions. Today, advances in materials science and bioengineering provide new ways to report temperature at the molecular level in real time. In this review, the scientific foundations and history of thermometry underpin a discussion of the discoveries emerging from the field of molecular thermometry. Intracellular nanogels and heat sensing biomolecules have been shown to accurately report temperature changes at the nanoscale. Various systems will soon provide the ability to accurately measure temperature changes at the tissue, cellular, and even subcellular level, allowing for detection and monitoring of very small changes in local temperature. In the clinic, this will lead to enhanced detection of tumors and localized infection, and accurate and precise monitoring of hyperthermia-based therapies. Some nanomaterial systems have even demonstrated a theranostic capacity for heat-sensitive, local delivery of chemotherapeutics. Just as early thermometry rapidly moved into the clinic, so too will these molecular thermometers.


Assuntos
Técnicas Biossensoriais , Técnicas de Diagnóstico Molecular , Nanomedicina/métodos , Nanotecnologia , Termografia , Técnicas Biossensoriais/instrumentação , Temperatura Corporal , Desenho de Equipamento , História do Século XVI , História do Século XIX , História do Século XX , Humanos , Técnicas de Diagnóstico Molecular/instrumentação , Nanomedicina/instrumentação , Nanotecnologia/instrumentação , Valor Preditivo dos Testes , Termodinâmica , Termografia/instrumentação , Termômetros/história
12.
J Cell Physiol ; 220(3): 569-73, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19452447

RESUMO

DNA damage by agents crosslinking the strands presents a formidable challenge to the cell to repair for survival and to repair accurately for maintenance of genetic information. It appears that repair of DNA crosslinks occurs in a path involving double strand breaks (DSBs) in the DNA. Mammalian cells have multiple systems involved in the repair response to such damage, including the Fanconi anemia pathway that appears to be directly involved, although the mechanisms and site of action remain elusive. A particular finding relating to deficiency of the Fanconi anemia pathway is the observation of chromosomal radial formations after ICL damage. The basis of formation of such chromosomal aberrations is unknown although they appear secondarily to DSBs. Here we review the processes involved in response to DNA interstrand crosslinks which might lead to radial formation and the role of the nucleotide excision repair gene, ERCC1, which is required for a normal response, not just to DNA crosslinks, but also for DSBs at collapsed replication forks caused by substrate depletion.


Assuntos
Núcleo Celular/efeitos dos fármacos , Quebras de DNA de Cadeia Dupla , Reparo do DNA , Anemia de Fanconi/genética , Mutagênicos/toxicidade , Animais , Núcleo Celular/enzimologia , Cromossomos Humanos/metabolismo , Replicação do DNA , Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo , Anemia de Fanconi/enzimologia , Humanos
13.
Proc Natl Acad Sci U S A ; 106(52): 22486-91, 2009 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-20080795

RESUMO

Emotional intelligence (EI) refers to a set of competencies that are essential features of human social life. Although the neural substrates of EI are virtually unknown, it is well established that the prefrontal cortex (PFC) plays a crucial role in human social-emotional behavior. We studied a unique sample of combat veterans from the Vietnam Head Injury Study, which is a prospective, long-term follow-up study of veterans with focal penetrating head injuries. We administered the Mayer-Salovey-Caruso Emotional Intelligence Test as a valid standardized psychometric measure of EI behavior to examine two key competencies of EI: (i) Strategic EI as the competency to understand emotional information and to apply it for the management of the self and of others and (ii) Experiential EI as the competency to perceive emotional information and to apply it for the integration into thinking. The results revealed that key competencies underlying EI depend on distinct neural PFC substrates. First, ventromedial PFC damage diminishes Strategic EI, and therefore, hinders the understanding and managing of emotional information. Second, dorsolateral PFC damage diminishes Experiential EI, and therefore, hinders the perception and integration of emotional information. In conclusion, EI should be viewed as complementary to cognitive intelligence and, when considered together, provide a more complete understanding of human intelligence.


Assuntos
Inteligência Emocional/fisiologia , Traumatismos Cranianos Penetrantes/fisiopatologia , Traumatismos Cranianos Penetrantes/psicologia , Estudos de Casos e Controles , Seguimentos , Traumatismos Cranianos Penetrantes/diagnóstico por imagem , Traumatismos Cranianos Penetrantes/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Córtex Pré-Frontal/diagnóstico por imagem , Córtex Pré-Frontal/lesões , Córtex Pré-Frontal/patologia , Córtex Pré-Frontal/fisiopatologia , Estudos Prospectivos , Psicometria , Tomografia Computadorizada por Raios X
14.
MAbs ; 1(6): 600-3, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20068401

RESUMO

Product life cycle management, which necessarily utilizes a multi-disciplinary approach, is an essential tool for companies that develop or market therapeutic monoclonal antibodies (mAbs). Too little attention to such a plan, or use of the wrong resources, could substantially curtail a product's life span. The most difficult part of the therapeutic antibody business is the development of high-quality, safe and effective products. Great care should thus be taken to ensure that products with these characteristics are positioned in a marketplace that is competition-free for as long as possible. In an era of mAbs with billion dollar markets, the loss of even a single day of sales could cost companies millions of dollars in lost revenue.


Assuntos
Anticorpos Monoclonais/economia , Imunoterapia , Legislação de Medicamentos , Anticorpos Monoclonais/uso terapêutico , Descoberta de Drogas/legislação & jurisprudência , Competição Econômica/legislação & jurisprudência , Humanos , Propriedade Intelectual , Marketing/legislação & jurisprudência , Patentes como Assunto , Gerenciamento da Prática Profissional
15.
MAbs ; 1(4): 382-4, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20068400

RESUMO

Patents provide one of the few protections companies can avail themselves of to help protect their therapeutic monoclonal antibody products. Just as the therapeutic monoclonal antibody field is constantly evolving, so too is the legal environment surrounding these inventions. In a series of articles, the general state of the law surrounding therapeutic antibodies will be explained, and important challenges to this technology area will be discussed. Much is at stake when companies market therapeutic monoclonal antibodies; therefore, a firm understanding of this important form of protection is critically important for anyone developing such products.


Assuntos
Anticorpos Monoclonais/biossíntese , Anticorpos Monoclonais/uso terapêutico , Patentes como Assunto/legislação & jurisprudência , Humanos , Propriedade
16.
MAbs ; 1(5): 417-21, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-20065635

RESUMO

Patent protection and FDA exclusivities are the two principal forms of protection available to companies that develop therapeutic monoclonal antibodies. Propo-sed changes to both forms of protection are currently being debated in the United States Congress. Specifically, Congress is presently debating both biosimilar and patent reform legislations. Although no bill has yet passed, it is expected that patent reform legislation should pass this year. It is less likely that a biosimilar bill will pass this year. However, when legislations are enacted, the changes will significantly impact the business of therapeutic monoclonal antibodies.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Legislação de Medicamentos , Patentes como Assunto/legislação & jurisprudência , Humanos , Legislação como Assunto , Estados Unidos , United States Food and Drug Administration/legislação & jurisprudência
17.
Philos Trans R Soc Lond B Biol Sci ; 363(1511): 3859-74, 2008 Dec 12.
Artigo em Inglês | MEDLINE | ID: mdl-18829425

RESUMO

The theory of games provides a mathematical formalization of strategic choices, which have been studied in both economics and neuroscience, and more recently has become the focus of neuroeconomics experiments with human and non-human actors. This paper reviews the results from a number of game experiments that establish a unitary system for forming subjective expected utility maps in the brain, and acting on these maps to produce choices. Social situations require the brain to build an understanding of the other person using neuronal mechanisms that share affective and intentional mental states. These systems allow subjects to better predict other players' choices, and allow them to modify their subjective utility maps to value pro-social strategies. New results for a trust game are presented, which show that the trust relationship includes systems common to both trusting and trustworthy behaviour, but they also show that the relative temporal positions of first and second players require computations unique to that role.


Assuntos
Encéfalo/fisiologia , Jogos Experimentais , Modelos Biológicos , Modelos Econômicos , Animais , Humanos
18.
Mol Genet Metab ; 95(1-2): 66-73, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18672388

RESUMO

The rare genetic disorder Fanconi anemia, caused by a deficiency in any of at least thirteen identified genes, is characterized by cellular sensitivity to DNA interstrand crosslinks and genome instability. The excision repair cross complementing protein, ERCC1, first identified as a participant in nucleotide excision repair, appears to also act in crosslink repair, possibly in incision and at a later stage. We have investigated the relationship of ERCC1 to the Fanconi anemia pathway, using depletion of ERCC1 by siRNA in transformed normal human fibroblasts and fibroblasts from Fanconi anemia patients. We find that depletion of ERCC1 does not hinder formation of double strand breaks in crosslink repair as indexed by gammaH2AX. However, the monoubiquitination of FANCD2 protein in response to MMC treatment is decreased and the localization of FANCD2 to nuclear foci is eliminated. Arrest of DNA replication by hydroxyurea, producing double strand breaks without crosslinks, also requires ERRC1 for FANCD2 localization to nuclear foci. Our results support a role for ERCC1 after creation of a double strand break for full activation of the Fanconi anemia pathway.


Assuntos
Núcleo Celular/metabolismo , Proteínas de Ligação a DNA/metabolismo , Endonucleases/metabolismo , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/metabolismo , Anemia de Fanconi/metabolismo , Linhagem Celular Transformada , Núcleo Celular/genética , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Quebras de DNA de Cadeia Dupla , Proteínas de Ligação a DNA/genética , Endonucleases/genética , Anemia de Fanconi/genética , Proteína do Grupo de Complementação D2 da Anemia de Fanconi/genética , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Histonas/genética , Histonas/metabolismo , Humanos , Mutagênicos/farmacologia , Transporte Proteico/efeitos dos fármacos , RNA Interferente Pequeno/genética , Ubiquitinação/efeitos dos fármacos
19.
Artigo em Inglês | MEDLINE | ID: mdl-19552301

RESUMO

Neuroeconomics has quickly attracted the attention of economists, psychologists, and neuroscientists. These scholars have joined to combine experimental methods and mathematical models from which novel results on brain and behavior have emerged. In this book the authors, who represent the cutting edge of this new discipline, draw connections between research in neuroeconomics and health economics. Moreover, they direct interested readers to a goldmine of additional references. Much of the research discussed here offers more questions than answers, and many of the answers are tentative first steps at a new understanding. It is precisely this that fuels our excitement about neuroeconomics.


Assuntos
Encéfalo/fisiologia , Tomada de Decisões/fisiologia , Atenção à Saúde/economia , Animais , Humanos , Modelos Neurológicos , Modelos Psicológicos
20.
Proc Natl Acad Sci U S A ; 104(50): 20084-9, 2007 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-18056800

RESUMO

Trust is a critical social process that helps us to cooperate with others and is present to some degree in all human interaction. However, the underlying brain mechanisms of conditional and unconditional trust in social reciprocal exchange are still obscure. Here, we used hyperfunctional magnetic resonance imaging, in which two strangers interacted online with one another in a sequential reciprocal trust game while their brains were simultaneously scanned. By designing a nonanonymous, alternating multiround game, trust became bidirectional, and we were able to quantify partnership building and maintenance. Using within- and between-brain analyses, an examination of functional brain activity supports the hypothesis that the preferential activation of different neuronal systems implements these two trust strategies. We show that the paracingulate cortex is critically involved in building a trust relationship by inferring another person's intentions to predict subsequent behavior. This more recently evolved brain region can be differently engaged to interact with more primitive neural systems in maintaining conditional and unconditional trust in a partnership. Conditional trust selectively activated the ventral tegmental area, a region linked to the evaluation of expected and realized reward, whereas unconditional trust selectively activated the septal area, a region linked to social attachment behavior. The interplay of these neural systems supports reciprocal exchange that operates beyond the immediate spheres of kinship, one of the distinguishing features of the human species.


Assuntos
Neurônios/fisiologia , Confiança/psicologia , Adulto , Comportamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neurofisiologia
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