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1.
Skin Res Technol ; 18(4): 389-96, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22136115

RESUMO

BACKGROUND: Telangiectasia, tiny skin vessels, are important dermoscopy structures used to discriminate basal cell carcinoma (BCC) from benign skin lesions. This research builds off of previously developed image analysis techniques to identify vessels automatically to discriminate benign lesions from BCCs. METHODS: A biologically inspired reinforcement learning approach is investigated in an adaptive critic design framework to apply action-dependent heuristic dynamic programming (ADHDP) for discrimination based on computed features using different skin lesion contrast variations to promote the discrimination process. Lesion discrimination results for ADHDP are compared with multilayer perception backpropagation artificial neural networks. RESULTS: This study uses a data set of 498 dermoscopy skin lesion images of 263 BCCs and 226 competitive benign images as the input sets. This data set is extended from previous research [Cheng et al., Skin Research and Technology, 2011, 17: 278]. Experimental results yielded a diagnostic accuracy as high as 84.6% using the ADHDP approach, providing an 8.03% improvement over a standard multilayer perception method. CONCLUSION: We have chosen BCC detection rather than vessel detection as the endpoint. Although vessel detection is inherently easier, BCC detection has potential direct clinical applications. Small BCCs are detectable early by dermoscopy and potentially detectable by the automated methods described in this research.


Assuntos
Carcinoma Basocelular/patologia , Dermoscopia/métodos , Interpretação de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Neoplasias Cutâneas/patologia , Telangiectasia/patologia , Inteligência Artificial , Carcinoma Basocelular/complicações , Diagnóstico Diferencial , Humanos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Neoplasias Cutâneas/complicações , Telangiectasia/complicações
2.
Opt Express ; 16(26): 21849-64, 2008 Dec 22.
Artigo em Inglês | MEDLINE | ID: mdl-19104618

RESUMO

Optical buffering is a major challenge in realizing all-optical packet switching. In this paper we propose a new buffer called a multipleinput single-output FIFO (MISO-FIFO) optical buffer that supports several functions normally associated with electronic RAM. Our structure reduces the physical size of a buffer by up to an order of magnitude or more by allowing reuse of its basic optical delay line (ODL) elements. Moreover, by using controllable fractional delay lines (CFDLs) as the basic building block we are able to reduce t size and frequency of voids in the output of the buffer. We develop a Markov Chain (MC) model for the performance of our new buffering scheme, and demonstrate the advantages of our structure over buffer structures that use ODLs in terms of throughput and link utilization.

3.
Contraception ; 37(2): 111-7, 1988 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-3370986

RESUMO

Gossypol was found to be an effective male contraceptive. The most serious side effect of gossypol contraception was the presumed lowering of serum potassium levels. The purpose of this present randomized and controlled study was to evaluate the merit of ingesting K salt or a potassium blocker while using gossypol. Results indicated that supplementation of K salt does not cause a reversal of the effect of gossypol on serum potassium levels and the blocker triamterene does not prevent loss of serum potassium.


Assuntos
Anticoncepcionais Masculinos/efeitos adversos , Gossipol/efeitos adversos , Hipopotassemia/induzido quimicamente , Potássio/farmacologia , Triantereno/farmacologia , Análise de Variância , Humanos , Masculino , Contagem de Espermatozoides/efeitos dos fármacos
4.
Poult Sci ; 73(8): 1334-40, 1994 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-7971678

RESUMO

Table eggs enriched with n-3 fatty acids may provide an alternative to fish as a source of these proposed healthful fatty acids. Successful marketing of this product may be influenced, however, by consumer perceptions of the egg as an unhealthful food. Therefore, the objectives of the current study were to assess consumer perceptions of table egg health quality and to determine the potential consumer acceptability of an n-3 fatty acid-enriched table egg. A survey was conducted in five major Texas cities; over 500 consumers completed the survey. Data were analyzed using the chi-square procedure. The majority of consumers surveyed considered eggs healthful and reported purchasing eggs at least once monthly and consuming an average of three whole eggs per week, as compared with an average reported fish consumption of only one serving per week. Sixty-five percent of the consumers reported willingness to purchase an n-3 fatty acid-enriched table egg and of these, 71% were willing to pay an additional $.50 per dozen. These data indicate that n-3 fatty acid-enriched table eggs represent a viable means of incorporating n-3 fatty acids into the diet of health-conscious consumers.


Assuntos
Comportamento do Consumidor , Ovos , Ácidos Graxos Ômega-3 , Alimentos Fortificados , Adulto , Idoso , Coleta de Dados , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Comput Biol Med ; 42(12): 1165-9, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23117020

RESUMO

Scale-crust, also termed "keratin crust", appears as yellowish-to-tan scale on the skin's surface. It is caused by hyperkeratosis and parakeratosis in inflamed areas of squamous cell carcinoma in situ (SCCIS, Bowen's disease) and is a critical dermoscopy feature for detecting this skin cancer. In contrast, scale appears as a white-to-ivory detaching layer of the skin, without crust, and is most commonly seen in benign lesions such as seborrheic keratoses (SK). Distinguishing scale-crust from ordinary scale in digital dermoscopy images holds promise for early SCCIS detection and differentiation from SK. Reported here are image analysis techniques that best characterize scale-crust in SCCIS and scale in SK, thereby allowing accurate separation of these two dermoscopic features. Classification using a logistic regression operating on color features extracted from these digital dermoscopy structures can reliably separate SCCIS from SK.


Assuntos
Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Dermoscopia/métodos , Processamento de Imagem Assistida por Computador/métodos , Ceratose Seborreica/diagnóstico , Ceratose Seborreica/patologia , Neoplasias Cutâneas/patologia , Área Sob a Curva , Bases de Dados Factuais , Diagnóstico Diferencial , Humanos , Queratinas/química , Modelos Logísticos , Curva ROC , Neoplasias Cutâneas/diagnóstico
6.
Am J Respir Crit Care Med ; 163(4): 881-6, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11282760

RESUMO

Inflammation is a critical component of asthma. Drugs that control asthma generally reduce the degree of airway inflammation. There is theoretical controversy surrounding the effects of beta(2)-agonists on airway inflammation, with some studies suggesting an anti-inflammatory effect, and others predicting a proinflammatory influence. We conducted a double-blind, placebo-controlled, crossover study of the effect of the long-acting beta(2)-agonist salmeterol on airway inflammation induced by segmental allergen challenge (SAC). We studied 13 allergic asthmatics controlled with as needed inhaled short-acting beta(2)-agonists alone, and used bronchoalveolar lavage 5 min and 48 h after SAC to assess airway inflammation, and the effects of salmeterol on this process. Salmeterol therapy improved FEV(1), but had no significant effect on the immediate or late cellular response to SAC. One measure of superoxide production was reduced, and interleukin-4 (IL-4) was reduced in baseline samples, but other indices of airway inflammation were unchanged by salmeterol therapy. We conclude that salmeterol therapy alone does not meaningfully reduce airway inflammation induced by SAC, but equally importantly, does not result in amplified inflammation.


Assuntos
Agonistas Adrenérgicos beta/administração & dosagem , Albuterol/análogos & derivados , Albuterol/administração & dosagem , Alérgenos , Asma/tratamento farmacológico , Hiper-Reatividade Brônquica/diagnóstico , Administração por Inalação , Adulto , Análise de Variância , Asma/complicações , Asma/diagnóstico , Biomarcadores/análise , Hiper-Reatividade Brônquica/complicações , Testes de Provocação Brônquica , Líquido da Lavagem Broncoalveolar/citologia , Broncoscopia , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Masculino , Pneumonia/complicações , Pneumonia/tratamento farmacológico , Probabilidade , Valores de Referência , Testes de Função Respiratória , Xinafoato de Salmeterol , Resultado do Tratamento
7.
J Pharmacol Exp Ther ; 278(3): 1215-27, 1996 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-8819505

RESUMO

3H-antagonists are known to bind to the alpha-2A adrenergic receptor with higher affinity in glycylglycine buffer than in Tris buffer. The purpose of this study was to examine the effect of buffers on the binding of antagonists to all four subtypes of the alpha-2 adrenergic receptor. Our approach was to examine the effects of glycylglycine, Tris, sodium phosphate (NaPO4) and potassium phosphate buffers on the binding of [3H]rauwolscine, [3H]RX821002, prazosin and oxymetazoline. We found that the affinities for the different subtypes varied with the buffer and the ligands used. Although the Bmax values varied somewhat with the buffers, they were similar for both radioligands for a specific subtype. The highest affinities and Bmax values for both radioligands were generally obtained with NaPO4 buffer. The affinities of antagonists in Tris buffer were always significantly lower than in either NaPO4 or glycylglycine buffer, and the affinities decreased as the concentration of Tris increased. In contrast, the affinity of norepinephrine for the alpha-2B subtype was higher in Tris than in NaPO4 buffer. The buffer effects did not appear to be dependent on the cell membrane composition. There appeared to be some species differences in the effects of buffers on the alpha-2C subtype. These results indicate that buffers affect the binding of antagonists to alpha-2 adrenergic receptors, that not all subtypes are altered in the same manner and that buffers alter the binding of different antagonists differently. It is generally recommended that NaPO4 buffer be used, and that Tris be avoided, when measuring the binding of antagonists to the alpha-2 adrenergic receptor.


Assuntos
Soluções Tampão , Idazoxano/análogos & derivados , Ensaio Radioligante/métodos , Receptores Adrenérgicos alfa 2/metabolismo , Ioimbina/metabolismo , Animais , Células CHO , Cricetinae , Humanos , Idazoxano/metabolismo , Cinética , Gambás , Oximetazolina/metabolismo , Prazosina/metabolismo , Ratos , Proteínas Recombinantes , Especificidade da Espécie
8.
Am J Respir Crit Care Med ; 156(1): 190-5, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9230746

RESUMO

Viral infections have been associated with cellular immune responses and production of Th-1 cytokines. Respiratory syncytial virus (RSV), however, induces virus-specific IgE, which might be a consequence of a Th-2-like activation. To test this hypothesis we quantified interferon-gamma (IFN-gamma) and interleukin-4 (IL-4) in the supernatant of peripheral blood mononuclear cells cultured for 24 and 48 h in the presence or absence of phytohemaglutinin and pokeweed mitogen and the lymphocyte phenotypes to analyze subsets and their activation markers, from 15 hospitalized infants during an acute lower respiratory infection caused by RSV and 17 healthy control infants from 1 to 15 mo of age. Compared with the control infants, those infected with RSV had an increase in the number of B-cells (p < 0.02) and decreases in both CD8+ T-cells (p < 0.01) and activated CD8+/CD25+ suppressor/ cytotoxic T-cells (p < 0.007). In RSV-infected infants, IFN-gamma production was subtotally suppressed, whereas IL-4 production was decreased to a lesser degree, giving significantly (p < 0.001) increased IL-4/IFN-gamma ratio compared with that in the control infants. These findings suggest a predominant Th-z-like response in RSV-infected infants, which could explain some aspects of the immunopathogenesis of RSV infection and the RSV-specific and nonspecific IgE antibody responses observed.


Assuntos
Interferon gama/sangue , Interleucina-4/sangue , Infecções por Vírus Respiratório Sincicial/imunologia , Antígenos Virais/sangue , Estudos de Casos e Controles , Células Cultivadas , Humanos , Lactente , Leucócitos Mononucleares/imunologia , Ativação Linfocitária , Subpopulações de Linfócitos/imunologia , Vírus Sinciciais Respiratórios/imunologia
9.
Am J Respir Crit Care Med ; 160(4): 1157-64, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10508802

RESUMO

Respiratory syncytial virus (RSV) and adenovirus (Advs) serotype 3 (Adv3) and 7h (Adv7h) are associated with mild to severe respiratory infection and are indistinguishable during the acute phases of the illnesses. However, outcome and long-term prognosis are different with both infections. RSV infection is associated with later development of asthma, and Adv, mainly Adv7h, with severe lung damage, bronchiectasis, and hyperlucent lung. We hypothesized that this difference could be partly due to different immune responses induced by these viruses. To test this hypothesis we quantified TCD4+, TCD8+, and BCD19+ expressing the interleukin-2 receptor-alpha chain (CD25) and interferon-gamma (IFN-gamma), interleukin (IL)-10, and IL-4 in the supernatant of peripheral blood mononuclear cells (PBMC) from school children infected in vitro with and without RSV, Adv7h, and Adv3 and after phytohemagglutinin (PHA) stimulation in the presence or absence of these viruses at a multiplicity of infection (MOI) of 1. PBMC from every child produced more IL-10 (p

Assuntos
Adenovírus Humanos/fisiologia , Citocinas/metabolismo , Leucócitos Mononucleares/metabolismo , Vírus Sincicial Respiratório Humano/fisiologia , Infecções por Adenovirus Humanos/imunologia , Células Cultivadas , Criança , Humanos , Interferon gama/metabolismo , Interleucina-10/metabolismo , Interleucina-4/metabolismo , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/virologia , Ativação Linfocitária , Subpopulações de Linfócitos/metabolismo , Receptores de Interleucina-2/metabolismo , Infecções por Vírus Respiratório Sincicial/imunologia
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