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1.
Ann Rheum Dis ; 73(3): 600-8, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24126456

RESUMO

OBJECTIVE: The histamine H4 receptor (H4R) has been shown to drive inflammatory responses in models of asthma, colitis and dermatitis, and in these models it appears to affect both innate and adaptive immune responses. In this study, we used both H4R-deficient mice and a specific H4R antagonist, JNJ 28307474, to investigate the involvement of the H4R in mouse arthritis models. METHODS: H4R-deficient mice and wild-type mice administered the H4R antagonist were studied in models of collagen antibody-induced arthritis (CAIA) and collagen-induced arthritis (CIA). The impact on Th17 cells was assessed by restimulation of inguinal lymphocytes in the disease or immunisation models and with in vitro stimulation of whole blood. RESULTS: Both H4R-deficient mice and mice treated with the H4R antagonist exhibited reduced arthritis disease severity in both CAIA and CIA models. This was evident from the reduction in disease score and in joint histology. In the CIA model, treatment with the H4R antagonist reduced the number of interleukin (IL)-17 positive cells in the lymph node and the total production of IL-17. Th17 cell development in vivo was reduced in H4R-deficient mice or in mice treated with an H4R antagonist. Finally, treatment of both mouse and human blood with an H4R antagonist reduced the production of IL-17 when cells were stimulated in vitro. CONCLUSIONS: These results implicate the H4R in disease progression in arthritis and in the production of IL-17 from Th17 cells. This work supports future clinical exploration of H4R antagonists for the treatment of rheumatoid arthritis.


Assuntos
Artrite Experimental/imunologia , Receptores Acoplados a Proteínas G/imunologia , Receptores Histamínicos/imunologia , Células Th17/imunologia , Animais , Artrite Experimental/patologia , Artrite Experimental/prevenção & controle , Células Cultivadas , Relação Dose-Resposta a Droga , Interleucina-17/biossíntese , Lipopolissacarídeos/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos DBA , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/deficiência , Receptores Histamínicos/deficiência , Receptores Histamínicos H4 , Índice de Gravidade de Doença
2.
Cancer Med ; 13(5)2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38501219

RESUMO

Mivavotinib (TAK-659/CB-659), a dual SYK/FLT3 inhibitor, reduced immunosuppressive immune cell populations and suppressed tumor growth in combination with anti-PD-1 therapy in cancer models. This dose-escalation/expansion study investigated the safety, pharmacokinetics, pharmacodynamics, and preliminary efficacy of mivavotinib plus nivolumab in patients with advanced solid tumors. Patients received oral mivavotinib 60-100 mg once-daily plus intravenous nivolumab 3 mg/kg on days 1 and 15 in 28-day cycles until disease progression or unacceptable toxicity. The dose-escalation phase evaluated the recommended phase II dose (RP2D; primary endpoint). The expansion phase evaluated overall response rate (primary end point) at the RP2D in patients with triple-negative breast cancer (TNBC). During dose-escalation (n = 24), two dose-limiting toxicities (grade 4 lipase increased and grade 3 pyrexia) occurred in patients who received mivavotinib 80 mg and 100 mg, respectively. The determined RP2D was once-daily mivavotinib 80 mg plus nivolumab 3 mg/kg. The expansion phase was terminated at ~50% enrollment (n = 17) after failing to meet an ad hoc efficacy futility threshold. Among all 41 patients, common treatment-emergent adverse events (TEAEs) included dyspnea (48.8%), aspartate aminotransferase increased, and pyrexia (46.3% each). Common grade ≥3 TEAEs were hypophosphatemia and anemia (26.8% each). Mivavotinib plasma exposure was generally dose-proportional (60-100 mg). One patient had a partial response. Mivavotinib 80 mg plus nivolumab 3 mg/kg was well tolerated with no new safety signals beyond those of single-agent mivavotinib or nivolumab. Low response rates highlight the challenges of treating unresponsive tumor types, such as TNBC, with this combination and immunotherapies in general. TRIAL REGISTRATION ID: NCT02834247.


Assuntos
Nivolumabe , Neoplasias de Mama Triplo Negativas , Humanos , Ensaios Clínicos Fase II como Assunto , Febre , Nivolumabe/efeitos adversos , Inibidores de Proteínas Quinases , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Feminino
3.
Clin Sci (Lond) ; 125(11): 533-42, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23799245

RESUMO

One feature of allergic asthma, the EAR (early allergic reaction), is not present in the commonly used mouse models. We therefore investigated the mediators involved in EAR in a guinea-pig in vivo model of allergic airway inflammation. Animals were sensitized using a single OVA (ovalbumin)/alum injection and challenged with aerosolized OVA on day 14. On day 15, airway resistance was assessed after challenge with OVA or MCh (methacholine) using the forced oscillation technique, and lung tissue was prepared for histology. The contribution of mast cell mediators was investigated using inhibitors of the main mast cell mediators [histamine (pyrilamine) and CysLTs (cysteinyl-leukotrienes) (montelukast) and prostanoids (indomethacin)]. OVA-sensitized and challenged animals demonstrated AHR (airway hyper-responsiveness) to MCh, and lung tissue eosinophilic inflammation. Antigen challenge induced a strong EAR in the sensitized animals. Treatment with a single compound, or indomethacin together with pyrilamine or montelukast, did not reduce the antigen-induced airway resistance. In contrast, dual treatment with pyrilamine together with montelukast, or triple inhibitor treatment, attenuated approximately 70% of the EAR. We conclude that, as in humans, the guinea-pig allergic inflammation model exhibits both EAR and AHR, supporting its suitability for in vivo identification of mast cell mediators that contribute to the development of asthma. Moreover, the known mast cell mediators histamine and leukotrienes were major contributors of the EAR. The data also lend further support to the concept that combination therapy with selective inhibitors of key mediators could improve asthma management.


Assuntos
Asma/fisiopatologia , Hiper-Reatividade Brônquica/patologia , Hipersensibilidade/patologia , Mastócitos/imunologia , Acetatos/uso terapêutico , Animais , Hiper-Reatividade Brônquica/induzido quimicamente , Hiper-Reatividade Brônquica/tratamento farmacológico , Constrição Patológica/induzido quimicamente , Constrição Patológica/patologia , Ciclopropanos , Modelos Animais de Doenças , Cobaias , Antagonistas dos Receptores Histamínicos/uso terapêutico , Indometacina/uso terapêutico , Antagonistas de Leucotrienos/uso terapêutico , Pulmão/efeitos dos fármacos , Pulmão/patologia , Mastócitos/patologia , Ovalbumina/farmacologia , Antagonistas de Prostaglandina/uso terapêutico , Pirilamina/uso terapêutico , Quinolinas/uso terapêutico , Sulfetos
4.
Inflamm Res ; 62(6): 599-607, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23532396

RESUMO

OBJECTIVE: Antagonism of the histamine H4 receptor (H4R) has been shown to be anti-inflammatory in a number of preclinical disease models, however the exact mechanisms behind this are still being uncovered. In vitro, the receptor interacts with TLR and impacts inflammatory mediator production from a number of different cell types. Here it is shown that this interaction also occurs in vivo. MATERIALS AND METHODS: Wild-type and H4R deficient BALB/c mice received an i.p. injection of LPS in PBS in conjunction with p.o. JNJ 7777120 or JNJ 28307474 (H4R antagonists). Two hours later blood was collected and TNF was measured. RESULTS: Two different H4R antagonists inhibited LPS-induced TNF production in mice and this production was also reduced in H4R-deficient mice. The TNF mRNA analysis showed that the major source of the cytokine was the liver and not blood, and that the H4R antagonist only reduced the expression levels in the liver. Depletion or inactivation of macrophages reduced the TNF levels and eliminated the H4R sensitivity. Treatment with an H4R antagonist also reduced LPS-induced liver injury and blocked LPS-enhanced lung inflammation in mice. CONCLUSION: The data support an interaction between H4R and TLR activation in vivo that can drive inflammatory responses.


Assuntos
Antagonistas dos Receptores Histamínicos/farmacologia , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Fator de Necrose Tumoral alfa/sangue , Alérgenos , Animais , Asma/induzido quimicamente , Asma/tratamento farmacológico , Asma/imunologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/imunologia , Feminino , Humanos , Indóis/farmacologia , Interleucina-13/imunologia , Células de Kupffer/metabolismo , Lipopolissacarídeos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Ovalbumina , Piperazinas/farmacologia , Receptores Acoplados a Proteínas G/fisiologia , Receptores Histamínicos/fisiologia , Receptores Histamínicos H4 , Fator de Necrose Tumoral alfa/genética
5.
Bioorg Med Chem Lett ; 23(3): 811-5, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23260350

RESUMO

Leukotrienes (LT's) are known to play a physiological role in inflammatory immune response. Leukotriene A(4) hydrolase (LTA(4)H) is a cystolic enzyme that stereospecifically catalyzes the transformation of LTA(4) to LTB(4). LTB(4) is a known pro-inflammatory mediator. This paper describes the identification and synthesis of substituted benzofurans as LTH(4)H inhibitors. The benzofuran series demonstrated reduced mouse and human whole blood LTB(4) levels in vitro and led to the identification one analog for advanced profiling. Benzofuran 28 showed dose responsive target engagement and provides a useful tool to explore a LTA(4)H inhibitor for the treatment of inflammatory diseases, such as asthma and inflammatory bowel disease (IBD).


Assuntos
Benzofuranos/química , Inibidores Enzimáticos/química , Epóxido Hidrolases/antagonistas & inibidores , Animais , Benzofuranos/farmacologia , Relação Dose-Resposta a Droga , Ativação Enzimática/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Humanos , Concentração Inibidora 50 , Camundongos , Estrutura Molecular , Ratos , Ratos Sprague-Dawley
6.
Neuroimage ; 60(2): 879-83, 2012 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-22306800

RESUMO

The ability to assess frontal lobe function in a rapid, objective, and standardized way, without the need for expertise in cognitive test administration might be particularly helpful in mild traumatic brain injury (TBI), where objective measures are needed. Functional near infrared spectroscopy (fNIRS) is a reliable technique to noninvasively measure local hemodynamic changes in brain areas near the head surface. In this paper, we are combining fNIRS and frameless stereotaxy which allowed us to co-register the functional images with previously acquired anatomical MRI volumes. In our experiment, the subjects were asked to perform a task, evaluating the complexity of daily life activities, previously shown with fMRI to activate areas of the anterior frontal cortex. We reconstructed averaged oxyhemoglobin and deoxyhemoglobin data from 20 healthy subjects in a spherical coordinate. The spherical coordinate is a natural representation of surface brain activation projection. Our results show surface activation projected from the medial frontopolar cortex which is consistent with previous fMRI results. With this original technique, we will construct a normative database for a simple cognitive test which can be useful in evaluating cognitive disability such as mild traumatic brain injury.


Assuntos
Lesões Encefálicas/fisiopatologia , Julgamento/fisiologia , Espectroscopia de Luz Próxima ao Infravermelho , Adulto , Bases de Dados Factuais , Feminino , Humanos , Masculino
7.
Bioorg Med Chem Lett ; 22(24): 7504-11, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23127888

RESUMO

Previously, benzthiazole containing LTA(4)H inhibitors were discovered that were potent (1-3), but were associated with the potential for a hERG liability. Utilizing medicinal chemistry first principles (e.g., introducing rigidity, lowering cLogD) a new benzthiazole series was designed, congeners of 1-3, which led to compounds 7a, 7c, 12a-d which exhibited LTA(4)H IC(50)=3-6 nM and hERG Dofetilide Binding IC(50)=8.9-> >10 µM.


Assuntos
Compostos Aza/farmacologia , Benzotiazóis/farmacologia , Inibidores Enzimáticos/farmacologia , Epóxido Hidrolases/antagonistas & inibidores , Animais , Compostos Aza/síntese química , Compostos Aza/química , Benzotiazóis/síntese química , Benzotiazóis/química , Relação Dose-Resposta a Droga , Desenho de Fármacos , Inibidores Enzimáticos/síntese química , Inibidores Enzimáticos/química , Epóxido Hidrolases/metabolismo , Canais de Potássio Éter-A-Go-Go/antagonistas & inibidores , Humanos , Camundongos , Estrutura Molecular , Relação Estrutura-Atividade
8.
Am J Respir Crit Care Med ; 181(9): 899-907, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-20110560

RESUMO

RATIONALE: Allergic asthma is characterized by reversible airway obstruction, lung inflammation, and airway hyperresponsiveness (AHR). Previous studies using leukotriene B(4) (LTB(4)) receptor 1-deficient mice and adoptive transfer experiments have suggested that LTB(4) plays a role in lung inflammation and AHR. OBJECTIVES: In this study, we used a leukotriene A(4) hydrolase (LTA(4)H) inhibitor as a pharmacological tool to directly examine the role of LTB(4) in a mast cell-dependent murine model of allergic airway inflammation. METHODS: We used the forced oscillation technique to test the effects of an LTA(4)H inhibitor dosed during the challenge phase on AHR. Lung tissue and lavage were collected for analysis. MEASUREMENTS AND MAIN RESULTS: Treatment with an LTA(4)H inhibitor improved multiple parameters encompassing AHR and lung function. Significant decreases in inflammatory leukocytes, cytokines, and mucin were observed in the lung lumen. Serum levels of antigen-specific IgE and IgG1 were also decreased. Labeled antigen uptake by lung dendritic cells and subsequent trafficking to draining lymph nodes and the lung were decreased on LTA(4)H inhibitor treatment. Provocatively, inhibition of LTA(4)H increased lipoxin A(4) levels in lung lavage fluid. CONCLUSIONS: These data suggest that LTB(4) plays a key role in driving lung inflammation and AHR. Mechanistically, we provide evidence that inhibition of LTA(4)H, affects recruitment of both CD4(+) and CD8(+) T cells, as well as trafficking of dendritic cells to draining lymph nodes, and may beneficially modulate other pro- and antiinflammatory eicosanoids in the lung. Inhibition of LTA(4)H is thus a potential therapeutic strategy that could modulate key aspects of asthma.


Assuntos
Asma/fisiopatologia , Hiper-Reatividade Brônquica/fisiopatologia , Epóxido Hidrolases/antagonistas & inibidores , Leucotrieno B4/fisiologia , Animais , Líquido da Lavagem Broncoalveolar/química , Células Cultivadas , Citocinas/análise , Imunoglobulina E/sangue , Leucotrieno B4/análise , Mastócitos/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Mucinas/análise , Ovalbumina/imunologia
9.
Respir Res ; 11: 86, 2010 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-20573261

RESUMO

BACKGROUND: Airway remodeling and dysfunction are characteristic features of asthma thought to be caused by aberrant production of Th2 cytokines. Histamine H4 receptor (H4R) perturbation has previously been shown to modify acute inflammation and Th2 cytokine production in a murine model of asthma. We examined the ability of H4R antagonists to therapeutically modify the effects of Th2 cytokine production such as goblet cell hyperplasia (GCH), and collagen deposition in a sub-chronic model of asthma. In addition, effects on Th2 mediated lung dysfunction were also determined. METHODS: Mice were sensitized to ovalbumin (OVA) followed by repeated airway challenge with OVA. After inflammation was established mice were dosed with the H4R antagonist, JNJ 7777120, or anti-IL-13 antibody for comparison. Airway hyperreactivity (AHR) was measured, lungs lavaged and tissues collected for analysis. RESULTS: Therapeutic H4R antagonism inhibited T cell infiltration in to the lung and decreased Th2 cytokines IL-13 and IL-5. IL-13 dependent remodeling parameters such as GCH and lung collagen were reduced. Intervention with H4R antagonist also improved measures of central and peripheral airway dysfunction. CONCLUSIONS: These data demonstrate that therapeutic H4R antagonism can significantly ameliorate allergen induced, Th2 cytokine driven pathologies such as lung remodeling and airway dysfunction. The ability of H4R antagonists to affect these key manifestations of asthma suggests their potential as novel human therapeutics.


Assuntos
Anti-Inflamatórios/farmacologia , Asma/tratamento farmacológico , Hiper-Reatividade Brônquica/tratamento farmacológico , Antagonistas dos Receptores Histamínicos/farmacologia , Indóis/farmacologia , Mediadores da Inflamação/metabolismo , Piperazinas/farmacologia , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Células Th2/efeitos dos fármacos , Remodelação das Vias Aéreas/efeitos dos fármacos , Animais , Anticorpos/farmacologia , Asma/imunologia , Asma/fisiopatologia , Hiper-Reatividade Brônquica/imunologia , Hiper-Reatividade Brônquica/fisiopatologia , Testes de Provocação Brônquica , Colágeno/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Feminino , Células Caliciformes/efeitos dos fármacos , Células Caliciformes/imunologia , Células Caliciformes/patologia , Hiperplasia , Interleucina-13/antagonistas & inibidores , Interleucina-13/metabolismo , Interleucina-5/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina , Receptores Acoplados a Proteínas G/metabolismo , Receptores Histamínicos/metabolismo , Receptores Histamínicos H4 , Células Th2/imunologia
10.
Mol Cancer Ther ; 7(3): 492-9, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18347137

RESUMO

B-RAF mutations have been identified in the majority of melanoma and a large fraction of colorectal and papillary thyroid carcinoma. Drug discovery efforts targeting mutated B-RAF have yielded several interesting molecules, and currently, three compounds are undergoing clinical evaluation. Inhibition of B-RAF in animal models leads to a slowing of tumor growth and, in some cases, tumor reduction. Described within is a novel series of diaryl imidazoles with potent, single-digit nanomolar, anti-B-RAF activity. One compound from this series has been detailed here and has been shown to block B-RAF(V600E)-dependent extracellular signal-regulated kinase 1/2 phosphorylation in SK-MEL-28 melanoma cells as well as soft agar colony formation and proliferation. Importantly, interleukin-8 (IL-8) was identified by quantitative real-time PCR and ELISA as a product of the elevated mitogen-activated protein kinase signaling in these cells. Plasma concentrations of IL-8 in mice bearing melanoma xenografts were significantly reduced following exposure to B-RAF inhibitors. Taken together, these data suggest that IL-8 could serve as a tractable clinical biomarker.


Assuntos
Biomarcadores Tumorais/metabolismo , Interleucina-8/antagonistas & inibidores , Melanoma/metabolismo , Proteínas Proto-Oncogênicas B-raf/antagonistas & inibidores , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Humanos , Imidazóis/farmacologia , Interleucina-8/biossíntese , Interleucina-8/genética , Melanoma/patologia , Fosforilação , Inibidores de Proteínas Quinases/farmacologia , RNA Mensageiro/genética , Transplante Heterólogo
11.
Nurse Educ Today ; 76: 172-177, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30784846

RESUMO

OBJECTIVES: Knowing there is a shortage of qualified nurses throughout the healthcare industry, it is imperative that program administrators understand the factors that affect nursing students as they select and commit to their academic major. They should consider key influences on potential students as new recruiting and retention tactics are developed and employed. Thus, we develop the current study to understand factors that shape students' commitment to nursing. Specifically, we attempt to discern how potential career growth, students' understanding of available occupational specialties, family members, and instructors affect nursing students' commitment to their chosen academic program. In addition, we analyze the mediating effect of stress in order to explain why some factors have more influence than others do. By conducting this research, we hope to provide insight into how to better recruit potential students and retain existing students already enrolled in nursing programs. DESIGN/SETTING/METHODS: Data collection took place in 2016 at one public and one private nursing program. The sample is understanding of available occupational specialties of 167 nursing student who completed a structured survey. Career growth, occupational specialties, instructors' and family influence were measured to understand how they affected major commitment and by extension intention to stay with their nursing program. We also assessed the potential mediating effect of stress on students' commitment to the nursing major. Ordinary least squares regression (SPSS version 22) was then used to evaluate both direct and mediated relationships. RESULTS: Based on the analysis, potential career growth, students' understanding of available occupational specialties, and family members directly affect nursing students' level of commitment to their chosen academic major. Results indicate that when students learn about the growth potential of the nursing profession or the different occupational specialties available that they will be more committed to the chosen major. The students likely believe the nursing profession aligns with their personal ambitions and skillsets. In addition, results indicate that stress fully mediates the level of commitment a student has towards nursing as an academic major. Evidence from the nursing students in this study indicates that their level of commitment to nursing programs is harmed by high levels of experienced stress. Students may feel that they identify with this area of study, but if they are stressed they may believe they lack the necessary abilities to succeed and/or perceive the nursing profession as undesirable to them personally. CONCLUSION: Understanding factors that influence students' commitment to an academic major is important to administrators as they work to improve the number of students enrolled in accredited nursing programs. Specifically, they can use insights from this study to better develop recruitment and retention programs by enabling students to garner feelings of pride, enthusiasm, and positively identify with the nursing profession.


Assuntos
Atitude do Pessoal de Saúde , Escolha da Profissão , Estresse Psicológico/psicologia , Estudantes de Enfermagem , Humanos
12.
Neuropharmacology ; 157: 107669, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31220484

RESUMO

Models to assess the addictive-like properties of nicotine in mice are limited. Therefore, we aimed to characterize and validate an addiction index by using an oral nicotine free-choice paradigm in mice. Adult C57BL/6J, DBA/2J, or genetically modified mice carrying deletions for nicotinic acetylcholine receptor (nAChR) subunits, (n = 8-10/sex/group) were given a choice of water or nicotine (10-960 µg/ml) solution using a two-bottle free-choice (2BC) paradigm. In general, oral nicotine intake and preference were higher in female mice compared to males. Absence of nicotine led to withdrawal, and intermittent access resulted in an escalation in consumption and greater nicotine withdrawal than continuous exposure. Additionally, oral nicotine consumption increased nucleus accumbens tyrosine hydroxylase levels. While ß2 and α6 KO mice showed a significant decrease in nicotine intake, deletion of α5 nAChRs increased nicotine consumption at high concentrations. Deletion of the α7 subunit altered the observed sex difference in nicotine consumption, with females consuming less than males. The α4ß2 partial agonist varenicline decreased oral nicotine consumption. Although addition of quinine to the nicotine solution lowered nicotine intake, mice primed with nicotine did not lower their intake after quinine addition. Nicotine deprivation followed by re-exposure showed increased nicotine consumption, and DBA/2J mice consumed less nicotine compared to C57BL/6J. We validated the mouse 2BC paradigm to study nicotine's addictive-like properties including nicotine intake, preference, withdrawal, and escalation of nicotine consumption during binge drinking or after reinstatement of a deprivation period.


Assuntos
Comportamento Aditivo/psicologia , Comportamento de Escolha/efeitos dos fármacos , Nicotina/farmacologia , Tabagismo/psicologia , Animais , Relação Dose-Resposta a Droga , Interações Medicamentosas , Feminino , Masculino , Camundongos , Camundongos Knockout , Nicotina/administração & dosagem , Núcleo Accumbens/metabolismo , Quinina/farmacologia , Receptores Nicotínicos/genética , Autoadministração , Caracteres Sexuais , Síndrome de Abstinência a Substâncias , Tirosina 3-Mono-Oxigenase/metabolismo , Vareniclina/farmacologia
13.
J Biomed Opt ; 13(2): 024025, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18465988

RESUMO

We present a novel method for estimating the intrinsic fluorescence lifetime of deeply embedded localized fluorophores. It is based on scaling relations, characteristic for turbid media. The approach is experimentally substantiated by successfully reconstructing lifetimes for targets at depths up to 14.5 mm. A derived correction factor was determined from the product of the transport-corrected scattering coefficient mu(s) (') and the index of refraction n(r). In addition, data from an array of detectors (> or =2) can be used to estimate mu(s) (')n(r). The suggested algorithm is a promising tool for diagnostic fluorescence, since lifetime can be a sensitive indicator of the fluorophore environment.


Assuntos
Algoritmos , Coloides/química , Microscopia de Fluorescência/métodos , Nefelometria e Turbidimetria/métodos , Reconhecimento Automatizado de Padrão/métodos , Espectrometria de Fluorescência/métodos , Coloides/análise
14.
Urol Oncol ; 36(12): 528.e15-528.e20, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30446447

RESUMO

INTRODUCTION AND OBJECTIVES: Free-hand transperineal prostate (fTP-Bx) biopsy offers an alternative to transrectal prostate biopsy (TRUS-Bx) in the diagnosis of prostate cancer. Our objectives were to determine whether fTP-Bx achieves cancer detection rates comparable to historic TRUS-Bx cohorts; to determine infectious and other complications associated with fTP-B; and to propose a standardized fTP-Bx template. PATIENTS AND METHODS: We present a single institution, retrospective review of fTP-Bx in 1,000 men with elevated prostate-specific antigen, abnormal digital rectal examination, or on an active surveillance protocol. A fan-like biopsy scheme was used in 883 patients. A 10-sector prostate biopsy template was developed for use in the final 117 patients. The primary outcome was detection of any cancer and detection of clinically significant cancer (Grade Group ≥ 2). Secondary outcomes included procedural specifics and complications. Chi Square and Mann-Whitney U were used for analysis of categorical and continuous variables, respectively. RESULTS: The median age of the cohort was 68 (interquartile range 61-74) years, and the median prostate-specific antigen was 7.9 (interquartile range 5.5-11.9) ng/ml. Total cancer (60.7%) and clinically significant cancer (40.3%) detection for fTP-Bx were comparable to those reported for TRUS-Bx. Detection of any cancer (70.9% vs. 59.3%, P < 0.01) and clinically significant cancer (51.3% vs. 38.9%, P = 0.01) was higher using the 10-sector biopsy template relative to the fan-like pattern. No patients were hospitalized for sepsis and no culture-proven urinary tract infections were diagnosed. CONCLUSION: Cancer detection rates using fTP-Bx are comparable to TRUS-Bx, and fTP-Bx nearly eliminates the risk of infection. We propose a 10-sector biopsy template for fTP-Bx that easily translates to established MRI prostate sector maps for use in clinical care and future research studies exploring the efficacy of MRI-guided fTP-Bx.


Assuntos
Exame Retal Digital , Biópsia Guiada por Imagem/métodos , Infecções , Imagem Multimodal/métodos , Neoplasias da Próstata/cirurgia , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Estudos Retrospectivos
15.
J Biomed Opt ; 12(5): 051604, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17994873

RESUMO

This research describes a noninvasive, noncontact method used to quantitatively analyze the functional characteristics of tissue. Multispectral images collected at several near-infrared wavelengths are input into a mathematical optical skin model that considers the contributions from different analytes in the epidermis and dermis skin layers. Through a reconstruction algorithm, we can quantify the percent of blood in a given area of tissue and the fraction of that blood that is oxygenated. Imaging normal tissue confirms previously reported values for the percent of blood in tissue and the percent of blood that is oxygenated in tissue and surrounding vasculature, for the normal state and when ischemia is induced. This methodology has been applied to assess vascular Kaposi's sarcoma lesions and the surrounding tissue before and during experimental therapies. The multispectral imaging technique has been combined with laser Doppler imaging to gain additional information. Results indicate that these techniques are able to provide quantitative and functional information about tissue changes during experimental drug therapy and investigate progression of disease before changes are visibly apparent, suggesting a potential for them to be used as complementary imaging techniques to clinical assessment.


Assuntos
Dermoscopia/métodos , Hemoglobinas/análise , Interpretação de Imagem Assistida por Computador/métodos , Sarcoma de Kaposi/patologia , Neoplasias Cutâneas/patologia , Espectrofotometria Infravermelho/métodos , Biomarcadores/análise , Humanos , Sarcoma de Kaposi/metabolismo , Neoplasias Cutâneas/metabolismo
16.
Med Phys ; 34(12): 4890-900, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18196814

RESUMO

In this paper we examine possible data types for time resolved fluorescence enhanced diffuse optical tomography (FDOT). FDOT is a particular case of diffuse optical tomography, where our goal is to analyze fluorophores deeply embedded in a turbid medium. We focus on the relative robustness of the different sets of data types to noise. We use an analytical model to generate the expected temporal point spread function (TPSF) and generate the data types from this. Varying levels of noise are applied to the TPSF before generating the data types. We show that local data types are more robust to noise than global data types, and should provide enhanced information to the inverse problem. We go on to show that with a simple reconstruction algorithm, depth and lifetime (the parameters of interest) of the fluorophore are better reconstructed using the local data types. Further we show that the relationship between depth and lifetime is better preserved for the local data types, suggesting they are in some way not only more robust, but also self-regularizing. We conclude that while the local data types may be more expensive to generate in the general case, they do offer clear advantages over the standard global data types.


Assuntos
Fluorescência , Raios Infravermelhos , Estatística como Assunto/métodos , Tomografia Óptica , Modelos Teóricos , Fenômenos Físicos , Física , Fatores de Tempo
17.
AANA J ; 85(4): 293-299, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31566549

RESUMO

Antibiotic prophylaxis plays an important role in the prevention of surgical site infections. For healthcare institutions to receive reimbursement, compliance with current measures introduced by the Surgical Care Improvement Project is required. Anesthesia providers commonly administer prophylactic antibiotics and are in the position to provide valuable input in the perioperative setting. This review provides a summary of the most common antibiotics used in the surgical setting-cefazolin, clindamycin, and vancomycin-and their implications to the anesthesia provider, such as proper dosing, targeting bacteria, and side effects.

18.
J Neurotrauma ; 32(22): 1693-721, 2015 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-26176603

RESUMO

The incidence of traumatic brain injury (TBI) in the United States was 3.5 million cases in 2009, according to the Centers for Disease Control and Prevention. It is a contributing factor in 30.5% of injury-related deaths among civilians. Additionally, since 2000, more than 260,000 service members were diagnosed with TBI, with the vast majority classified as mild or concussive (76%). The objective assessment of TBI via imaging is a critical research gap, both in the military and civilian communities. In 2011, the Department of Defense (DoD) prepared a congressional report summarizing the effectiveness of seven neuroimaging modalities (computed tomography [CT], magnetic resonance imaging [MRI], transcranial Doppler [TCD], positron emission tomography, single photon emission computed tomography, electrophysiologic techniques [magnetoencephalography and electroencephalography], and functional near-infrared spectroscopy) to assess the spectrum of TBI from concussion to coma. For this report, neuroimaging experts identified the most relevant peer-reviewed publications and assessed the quality of the literature for each of these imaging technique in the clinical and research settings. Although CT, MRI, and TCD were determined to be the most useful modalities in the clinical setting, no single imaging modality proved sufficient for all patients due to the heterogeneity of TBI. All imaging modalities reviewed demonstrated the potential to emerge as part of future clinical care. This paper describes and updates the results of the DoD report and also expands on the use of angiography in patients with TBI.


Assuntos
Lesões Encefálicas/diagnóstico , Neuroimagem/métodos , Lesões Encefálicas/diagnóstico por imagem , Eletroencefalografia , Humanos , Imageamento por Ressonância Magnética , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia Computadorizada por Raios X , Ultrassonografia Doppler Transcraniana
19.
J Biomed Opt ; 17(12): 125004, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23208294

RESUMO

Fluorescence correlation spectroscopy (FCS) is increasingly being used to assess the movement of particles diffusing in complex, optically dense surroundings, in which case measurement conditions may complicate data interpretation. It is considered how a single-photon FCS measurement can be affected if the sample properties result in scattering of the incident light. FCS autocorrelation functions of Atto 488 dye molecules diffusing in solutions of polystyrene beads are measured, which acted as scatterers. Data indicated that a scattering-linked increase in the illuminated volume, as much as two fold, resulted in minimal increase in diffusivity. To analyze the illuminated beam profile, Monte-Carlo simulations were employed, which indicated a larger broadening of the beam along the axial than the radial directions, and a reduction of the incident intensity at the focal point. The broadening of the volume in the axial direction has only negligible effect on the measured diffusion time, since intensity fluctuations due to diffusion events in the radial direction are dominant in FCS measurements. Collectively, results indicate that multiple scattering does not result in FCS measurement artifacts and thus, when sufficient signal intensity is attainable, single-photon FCS can be a useful technique for measuring probe diffusivity in optically dense media.


Assuntos
Corantes Fluorescentes/análise , Corantes Fluorescentes/química , Imagem Molecular/métodos , Nefelometria e Turbidimetria/métodos , Espectrometria de Fluorescência/métodos , Simulação por Computador , Luz , Modelos Estatísticos , Tamanho da Partícula , Espalhamento de Radiação , Viscosidade
20.
Biomed Opt Express ; 3(1): 192-205, 2012 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-22254179

RESUMO

In this paper we discuss results based on using instrumental motion as a signal rather than treating it as noise in Near Infra-Red (NIR) imaging. As a practical application to demonstrate this approach we show the design of a novel NIR hematoma detection device. The proposed device is based on a simplified single source configuration with a dual separation detector array and uses motion as a signal for detecting changes in blood volume in the dural regions of the head. The rapid triage of hematomas in the emergency room will lead to improved use of more sophisticated/expensive imaging facilities such as CT/MRI units. We present simulation results demonstrating the viability of such a device and initial phantom results from a proof of principle device. The results demonstrate excellent localization of inclusions as well as good quantitative comparisons.

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