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1.
Dev Sci ; 22(3): e12796, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30589167

RESUMO

What are the origins of object permanence? Despite widespread interest in this question, methodological barriers have prevented detailed analysis of how experience shapes the development of object permanence in newborn organisms. Here, we introduce an automated controlled-rearing method for studying the emergence of object permanence in strictly controlled virtual environments. We used newborn chicks as an animal model and recorded their behavior continuously (24/7) from the onset of vision. Across four experiments, we found that object permanence can develop rapidly, within the first few days of life. This ability developed even when chicks were reared in impoverished visual environments containing no object occlusion events. Object permanence failed to develop, however, when chicks were reared in environments containing temporally non-smooth objects (objects moving on discontinuous spatiotemporal paths). These results suggest that experience with temporally smooth objects facilitates the development of object permanence, confirming a key prediction of temporal learning models in computational neuroscience.


Assuntos
Aprendizagem/fisiologia , Memória/fisiologia , Reconhecimento Psicológico/fisiologia , Percepção Visual/fisiologia , Animais , Animais Recém-Nascidos , Conscientização , Galinhas , Humanos , Recém-Nascido , Modelos Animais , Visão Ocular
2.
Anim Cogn ; 19(4): 835-45, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27079969

RESUMO

To what extent are newborn brains designed to operate over natural visual input? To address this question, we used a high-throughput controlled-rearing method to examine whether newborn chicks (Gallus gallus) show enhanced learning of natural visual sequences at the onset of vision. We took the same set of images and grouped them into either natural sequences (i.e., sequences showing different viewpoints of the same real-world object) or unnatural sequences (i.e., sequences showing different images of different real-world objects). When raised in virtual worlds containing natural sequences, newborn chicks developed the ability to recognize familiar images of objects. Conversely, when raised in virtual worlds containing unnatural sequences, newborn chicks' object recognition abilities were severely impaired. In fact, the majority of the chicks raised with the unnatural sequences failed to recognize familiar images of objects despite acquiring over 100 h of visual experience with those images. Thus, newborn chicks show enhanced learning of natural visual sequences at the onset of vision. These results indicate that newborn brains are designed to operate over natural visual input.


Assuntos
Animais Recém-Nascidos , Aprendizagem , Percepção Visual , Animais , Galinhas , Reconhecimento Psicológico , Visão Ocular
3.
Cogn Affect Behav Neurosci ; 14(3): 923-38, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24430617

RESUMO

One factor that influences the success of emotion regulation is the manner in which the regulated emotion was generated. Recent research has suggested that reappraisal, a top-down emotion regulation strategy, is more effective in decreasing self-reported negative affect when emotions were generated from the top-down, versus the bottom-up. On the basis of a process overlap framework, we hypothesized that the neural regions active during reappraisal would overlap more with emotions that were generated from the top-down, rather than from the bottom-up. In addition, we hypothesized that increased neural overlap between reappraisal and the history effects of top-down emotion generation would be associated with increased reappraisal success. The results of several analyses suggested that reappraisal and emotions that were generated from the top-down share a core network of prefrontal, temporal, and cingulate regions. This overlap is specific; no such overlap was observed between reappraisal and emotions that were generated in a bottom-up fashion. This network consists of regions previously implicated in linguistic processing, cognitive control, and self-relevant appraisals, which are processes thought to be crucial to both reappraisal and top-down emotion generation. Furthermore, individuals with high reappraisal success demonstrated greater neural overlap between reappraisal and the history of top-down emotion generation than did those with low reappraisal success. The overlap of these key regions, reflecting overlapping processes, provides an initial insight into the mechanism by which generation history may facilitate emotion regulation.


Assuntos
Mapeamento Encefálico , Encéfalo/irrigação sanguínea , Encéfalo/fisiologia , Cognição/fisiologia , Emoções/fisiologia , Imageamento por Ressonância Magnética , Reconhecimento Visual de Modelos/fisiologia , Estimulação Acústica , Adulto , Feminino , Lateralidade Funcional , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Vias Neurais/irrigação sanguínea , Vias Neurais/fisiologia , Testes Neuropsicológicos , Oxigênio/sangue , Adulto Jovem
4.
Catheter Cardiovasc Interv ; 83(3): 369-74, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23765847

RESUMO

OBJECTIVE: To compare the use of regadenoson to adenosine for measurement of fractional flow reserve (FFR). BACKGROUND: FFR is an accepted method to assess the functional significance of intermediate coronary artery stenoses and uses adenosine to induce maximal hyperemia. The use of the selective A2a receptor agonist regadenoson for FFR is not established. METHODS: Fifty-seven patients undergoing clinically indicated FFR assessment of intermediate coronary stenoses were included. For the initial assessment of FFR, hyperemia was achieved by a standard intravenous adenosine infusion (140 mcg/kg/min). After a washout period of 10 min, FFR was reassessed using regadenoson as a single 0.4 mg intravenous bolus. FFR measurements were recorded at baseline and following maximal hyperemia with both agents. RESULTS: Mean age was 57 ± 8 years and 47 were male. Sixty coronary lesions were evaluated and were located in the left anterior descending in 34, the left circumflex in 9, right coronary in 15, and left main coronary artery in 2. Mean ( ± SD) FFR following adenosine and regadenoson was 0.79 ( ± 0.09) and 0.79 (±0.09), respectively, P = NS. Time to FFR nadir was shorter with regadenoson compared to adenosine, 36.6 ± 24 versus 66 ± 0.19 sec, P < 0.0001, respectively. No patients experienced any significant side effects related to regadenoson. CONCLUSIONS: Regadenoson is a viable alternative to intravenous adenosine for achieving maximal hyperemia during FFR assessment. Compared to adenosine, regadenoson has a similar hemodynamic response, achieves more rapid hyperemia, is easier to use, and has an excellent side-effect profile.


Assuntos
Agonistas do Receptor A2 de Adenosina , Adenosina , Cateterismo Cardíaco , Estenose Coronária/diagnóstico , Reserva Fracionada de Fluxo Miocárdico , Purinas , Pirazóis , Vasodilatadores , Adenosina/administração & dosagem , Adenosina/efeitos adversos , Agonistas do Receptor A2 de Adenosina/administração & dosagem , Agonistas do Receptor A2 de Adenosina/efeitos adversos , Idoso , Angiografia Coronária , Estenose Coronária/fisiopatologia , Feminino , Hemodinâmica , Humanos , Hiperemia/fisiopatologia , Infusões Intravenosas , Injeções Intravenosas , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Prognóstico , Purinas/administração & dosagem , Purinas/efeitos adversos , Pirazóis/administração & dosagem , Pirazóis/efeitos adversos , Reprodutibilidade dos Testes , Índice de Gravidade de Doença , Vasodilatadores/administração & dosagem , Vasodilatadores/efeitos adversos
5.
Abdom Radiol (NY) ; 49(5): 1716-1733, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38691132

RESUMO

There is a diverse group of non-gastrointestinal stromal tumor (GIST), mesenchymal neoplasms of the gastrointestinal (GI) tract that demonstrate characteristic pathology and histogenesis as well as variable imaging findings and biological behavior. Recent advancements in tumor genetics have unveiled specific abnormalities associated with certain tumors, influencing their molecular pathogenesis, biology, response to treatment, and prognosis. Notably, giant fibrovascular polyps of the esophagus, identified through MDM2 gene amplifications, are now classified as liposarcomas. Some tumors exhibit distinctive patterns of disease distribution. Glomus tumors and plexiform fibromyxomas exhibit a pronounced affinity for the gastric antrum. In contrast, smooth muscle tumors within the GI tract are predominantly found in the esophagus and colorectum, surpassing the incidence of GISTs in these locations. Surgical resection suffices for symptomatic benign tumors; multimodality treatment may be necessary for frank sarcomas. This article aims to elucidate the cross-sectional imaging findings associated with a wide spectrum of these tumors, providing insights that align with their histopathological features.


Assuntos
Neoplasias Gastrointestinais , Humanos , Neoplasias Gastrointestinais/diagnóstico por imagem , Neoplasias Gastrointestinais/genética , Neoplasias Gastrointestinais/patologia , Tumores do Estroma Gastrointestinal/diagnóstico por imagem , Tumores do Estroma Gastrointestinal/genética , Tumores do Estroma Gastrointestinal/patologia , Diagnóstico por Imagem/métodos
6.
Abdom Radiol (NY) ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38937338

RESUMO

A wide spectrum of benign and malignant primary mesenchymal tumors and tumor-like lesions of the spleen has been recently included under the umbrella term 'stroma-derived' neoplasms and tumor-like lesions. These include dendritic cell neoplasms such as follicular dendritic cell sarcoma, EBV-positive inflammatory follicular dendritic cell sarcoma, and fibroblastic reticular cell tumor; smooth muscle and myofibroblastic lesions such as inflammatory pseudotumor, EBV-associated smooth muscle tumor and undifferentiated pleomorphic sarcoma as well as a diverse spectrum of vascular and vascular-stromal tumors and tumor-like lesions. While some tumor and tumor-like lesions are unique to the spleen, others may also occur in diverse extra-splenic viscera. These tumors and tumor-like lesions demonstrate characteristic histopathology, immunocytochemistry and biological behavior. While cross-sectional imaging studies allow detection, staging and limited characterization of these splenic lesions, histopathological confirmation permits optimal management and surveillance strategies.

7.
J Clin Microbiol ; 51(8): 2541-50, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23698534

RESUMO

In recent years, the dramatic increase in community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections has become a significant health care challenge. Early detection of CA-MRSA is important because of its increased virulence associated with the arginine catabolic mobile element (ACME), Panton-Valentine leukocidin (PVL), and other toxins that may contribute to disease severity. In particular, the USA300 epidemic clone has emerged and now represents the cause of as much as 98% of CA-MRSA skin and soft tissue infections in the United States. Current diagnostic assays used to identify CA-MRSA strains are based on complex multiplex PCRs targeting the staphylococcal cassette chromosome mec (SCCmec) DNA junction, a multitude of genes, and noncoding DNA fragments or on a number of lengthy sequence-typing methods. Here, two nucleotide polymorphisms, G88A and G2047A, that were found to be in strict linkage disequilibrium in the S. aureus penicillin-binding protein 3 (pbp3) gene were also found to be highly associated with the USA300 clone of CA-MRSA. Clinical isolates that contained this pbp3 allele were also positive for the presence of SCCmec type IV, the ACME, and the PVL toxin gene and matched the t008 or t121 molecular spa types, which are associated specifically with the USA300 CA-MRSA clone. A single allele-specific PCR targeting the G88A polymorphism was developed and was found to be 100% sensitive and specific for the detection of USA300 CA-MRSA and 91.5% sensitive and 100% specific for the detection of all CA-MRSA isolates in this study.


Assuntos
Técnicas Bacteriológicas/métodos , Infecções Comunitárias Adquiridas/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Técnicas de Diagnóstico Molecular/métodos , Proteínas de Ligação às Penicilinas/genética , Reação em Cadeia da Polimerase/métodos , Infecções Estafilocócicas/microbiologia , Alelos , Genes Bacterianos , Humanos , Desequilíbrio de Ligação , Staphylococcus aureus Resistente à Meticilina/genética , Sensibilidade e Especificidade , Estados Unidos , Fatores de Virulência/genética
8.
PDA J Pharm Sci Technol ; 74(3): 318-323, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31843986

RESUMO

Investigations into environmental monitoring (EM) excursions can be prolonged and do not always result in clear root causes or corrective and preventative actions. This article outlines how biofluorescent particle counting (BFPC) can be used in investigations to eliminate the inherent delays of culture-based methods. The application for investigations supplements routine EM, acting as a risk-reduction tool enabling real-time detection of viable microorganisms in air samples and supporting root cause analysis and remedial actions. The article includes guidance on how to use the technology, a real case study involving a mold excursion, and examples of business benefits achieved by various companies.


Assuntos
Filtros de Ar/normas , Microbiologia do Ar/normas , Contaminação de Medicamentos/prevenção & controle , Monitoramento Ambiental/normas , Corantes Fluorescentes/análise , Tamanho da Partícula , Monitoramento Ambiental/métodos , Humanos
9.
PDA J Pharm Sci Technol ; 73(2): 121-134, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30361285

RESUMO

This paper provides recommendations for quality oversight, manufacturing operations, and industry perspective of regulatory expectations to enable aseptic facilities to move toward real-time and continuous microbiological environmental monitoring, thereby reducing interventions and future replacement of Grade A settle plates and nonremote active air sampling. The replacement of traditional monitoring with biofluorescent particle-counting systems provides an improvement in process understanding and product safety and reduces operator manipulations, assuring product quality and real-time process verification. The future state pharmaceutical technology roadmaps include gloveless isolators with real-time and continuous monitoring for aseptic manufacturing.LAY ABSTRACT: This paper advocates the use of an alternative and relatively new method of monitoring the air for contamination in biopharmaceutical manufacturing facilities. The alternative method is based on a type of instrument the authors refer to as a biofluorescent particle counter (BFPC). The BFPC method has the advantage of being able to detect airborne microorganisms continuously and to record the actual time of detection. The replacement of traditional monitoring with BFPC systems can provide better data, which can be used to improve the understanding of contamination risks in complex manufacturing processes, ultimately providing more confidence in product safety. The authors present data showing the suitability of BFPC. This immediate result is very useful for picking up early any possible contamination and should, therefore, provide a better way to monitor and control the risk of contamination. As traditional monitoring methods require manual manipulation, an additional advantage of BFPC systems is that they can reduce manual manipulations. Elimination of all interventions is a goal in the industry, because although they are tightly controlled, interventions are an unwanted potential source of contamination.


Assuntos
Contaminação de Medicamentos/prevenção & controle , Ambiente Controlado , Monitoramento Ambiental/métodos , Tecnologia Farmacêutica/métodos , Microbiologia do Ar/normas , Indústria Farmacêutica/métodos , Indústria Farmacêutica/normas
10.
J Cardiovasc Pharmacol Ther ; 13(4): 269-78, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19087950

RESUMO

Levosimendan increases the sensitivity of the cardiac fibrils to calcium, favorably affects hemodynamics in patients with heart failure. It is a positive inotrope and a peripheral vasodilator. The elimination half-life of the compound is about 1 hour. The drug decreases pulmonary capillary wedge pressure, increases cardiac output with the improvement in left ventricular ejection fraction leading to symptomatic improvement which includes decreased dyspnea and fatigue. Levosimendan can be used safely with diuretics, nitrates, beta-blockers, digoxin, and angiotensin-converting enzyme inhibitors. The most common adverse effects of levosimendan are headache and hypotension. Prolongation of the QTc interval does not appear to increase the incidence of arrhythmias, including ventricular tachycardia, ventricular fibrillation, and torsades de pointes. Levosimendan is a novel agent in the treatment of decompensated heart failure, representing a newer class of medications aimed at increasing calcium sensitivity. Its properties holds promise for the treatment of heart failure but further large-scale studies will be needed to determine its precise efficacy, safety, as well as the compound's long-term impact on mortality.


Assuntos
Cálcio/metabolismo , Proteínas Contráteis/metabolismo , Hidrazonas/farmacologia , Miocárdio/metabolismo , Piridazinas/farmacologia , Cardiotônicos/efeitos adversos , Cardiotônicos/farmacologia , Cardiotônicos/uso terapêutico , Cefaleia/induzido quimicamente , Insuficiência Cardíaca/tratamento farmacológico , Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Humanos , Hidrazonas/efeitos adversos , Hidrazonas/uso terapêutico , Hipotensão/induzido quimicamente , Piridazinas/efeitos adversos , Piridazinas/uso terapêutico , Ensaios Clínicos Controlados Aleatórios como Assunto , Simendana
11.
ACS Cent Sci ; 3(7): 751-758, 2017 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-28776017

RESUMO

While ∼75% of commercially utilized polymers are semicrystalline, the generally low mechanical modulus of these materials, especially for those possessing a glass transition temperature below room temperature, restricts their use for structural applications. Our focus in this paper is to address this deficiency through the controlled, multiscale assembly of nanoparticles (NPs), in particular by leveraging the kinetics of polymer crystallization. This process yields a multiscale NP structure that is templated by the lamellar semicrystalline polymer morphology and spans NPs engulfed by the growing crystals, NPs ordered into layers in the interlamellar zone [spacing of [Formula: see text] (10-100 nm)], and NPs assembled into fractal objects at the interfibrillar scale, [Formula: see text] (1-10 µm). The relative fraction of NPs in this hierarchy is readily manipulated by the crystallization speed. Adding NPs usually increases the Young's modulus of the polymer, but the effects of multiscale ordering are nearly an order of magnitude larger than those for a state where the NPs are not ordered, i.e., randomly dispersed in the matrix. Since the material's fracture toughness remains practically unaffected in this process, this assembly strategy allows us to create high modulus materials that retain the attractive high toughness and low density of polymers.

12.
Soc Cogn Affect Neurosci ; 7(3): 253-62, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21296865

RESUMO

Emotion regulation plays a crucial role in adaptive functioning and mounting evidence suggests that some emotion regulation strategies are often more effective than others. However, little attention has been paid to the different ways emotions can be generated: from the 'bottom-up' (in response to inherently emotional perceptual properties of the stimulus) or 'top-down' (in response to cognitive evaluations). Based on a process priming principle, we hypothesized that mode of emotion generation would interact with subsequent emotion regulation. Specifically, we predicted that top-down emotions would be more successfully regulated by a top-down regulation strategy than bottom-up emotions. To test this hypothesis, we induced bottom-up and top-down emotions, and asked participants to decrease the negative impact of these emotions using cognitive reappraisal. We observed the predicted interaction between generation and regulation in two measures of emotional responding. As measured by self-reported affect, cognitive reappraisal was more successful on top-down generated emotions than bottom-up generated emotions. Neurally, reappraisal of bottom-up generated emotions resulted in a paradoxical increase of amygdala activity. This interaction between mode of emotion generation and subsequent regulation should be taken into account when comparing of the efficacy of different types of emotion regulation, as well as when reappraisal is used to treat different types of clinical disorders.


Assuntos
Tonsila do Cerebelo/fisiologia , Mapeamento Encefálico , Cognição/fisiologia , Emoções/fisiologia , Adolescente , Adulto , Face , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Vias Neurais/fisiologia , Testes Neuropsicológicos , Reconhecimento Visual de Modelos , Estimulação Luminosa , Autorrelato , Adulto Jovem
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