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1.
Artigo em Inglês | MEDLINE | ID: mdl-39233517

RESUMO

OBJECTIVES: To assess the relative frequency and associated factors of disorders of gut-brain interaction (DGBIs) in outpatient gastrointestinal (GI) clinics in young children of Latin America. METHODS: Cross-sectional study in 10 pediatric GI outpatient clinics (private and public) in five countries of Latin America (El Salvador, México, Colombia, Panamá, and Nicaragua). Parents of patients 1 month 4 years of age from outpatient clinics complete/d a diagnostic questionnaire for DGBIs per Rome IV criteria (QPGS-IV, Spanish version). We conducted descriptive analysis, two-sample t-tests and chi-square tests, univariate analyses, and logistic regression to evaluate risk factors. RESULTS: We collected data from 783 children. In total, 34.5% had a DGBI. Overall, functional constipation (FC) was the most common diagnosis (23.4%) in children of all ages (infants, 16.1%, 1-4-years-old, 32.7%). In infants, the second most common DGBI was regurgitation (6.6%) and in 1-4-years-old and cyclic vomiting syndrome (4.1%). The diagnosis of a DGBI was significantly associated with a family history of DGBIs (odds ratio [OR] 2.97, 95% confidence interval [CI] 1.61-5.57, p = 0.0001). Patients who identified as black (OR 2.25, 95% CI 1.28-3.92, p = 0.0021) or mixed race (OR 1.76, 95% CI 1.25-2.48, p = 0.0006) were also significantly associated with a higher likelihood of DGBIs. CONCLUSIONS: DGBIs are a common diagnosis in pediatric GI clinics of Latin America. Overall, FC was the most common DGBI.

2.
J Nucl Cardiol ; 30(3): 1075-1087, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36266526

RESUMO

BACKGROUND: Somatostatin receptor is expressed in sarcoid granulomas, and preliminary clinical studies have shown that myocardial sarcoidosis can be identified on somatostatin receptor-targeted PET. We examined the potential clinical use of 68Ga-DOTATATE PET/CT for diagnosis and response assessment in cardiac sarcoidosis compared to 18F-FDG PET/CT. METHODS: Eleven cardiac sarcoidosis patients with 18F-FDG PET/CT were prospectively enrolled for cardiac 68Ga-DOTATATE PET/CT. The two PET/CT studies were interpreted independently and were compared for patient-level and segment-level concordance, as well as for the degree of radiotracer uptake. Follow-up 68Ga-DOTATATE PET/CT was performed in eight patients. RESULTS: Patient-level concordance was 91%: ten patients had multifocal DOTATATE uptake (active cardiac sarcoidosis) and one patient showed diffuse DOTATATE uptake. Segment-level agreement was 77.1% (Kappa 0.53 ± 0.07). The SUVmax-to-blood pool ratio was lower on 68Ga-DOTATATE PET/CT (3.2 ± 0.6 vs. 4.9 ± 1.5, P = 0.006 on paired t test). Follow-up 68Ga-DOTATATE PET/CT showed one case of complete response and one case of partial response, while 18F-FDG PET/CT showed four cases of response, including three with complete response. CONCLUSION: Compared to 18F-FDG PET/CT, 68Ga-DOTATATE PET/CT can identify active cardiac sarcoidosis with high patient-level concordance, but with moderate segment-level concordance, low signal-to-background ratio, and underestimation of treatment response.


Assuntos
Compostos Organometálicos , Sarcoidose , Humanos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Fluordesoxiglucose F18 , Radioisótopos de Gálio , Receptores de Somatostatina
3.
An Acad Bras Cienc ; 95(2): e20201783, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37531490

RESUMO

Although widely used in medicine, separation technology, and other fields, the effects of cyclodextrins on the activities of phosphoryl transfer enzymes have not been previously evaluated. In vivo studies evaluated the function of cyclodextrins as active compounds. Despite the use of cyclodextrins as active compounds, the effects of cyclodextrins on hepatic and renal tissues remain to be fully elucidated. The primary objective of this study was to evaluate the effects of ß- cyclodextrins, methyl-ß-cyclodextrin (M-ß- cyclodextrins), and (2-hydroxypropyl)-ß-cyclodextrin (HP-ß-cyclodextrins) on enzyme activities regulating the maintenance of energy homeostasis in the kidney and liver tissues in relation to toxicity. Serum levels of liver and kidney markers were measured, and oxidative stress parameters were assessed. After 60-day treatments, we observed that the administration of ß-cyclodextrins and M-ß-cyclodextrins inhibited the hepatic activity of pyruvate kinase, an irreversible enzyme within the glycolytic pathway. Additionally, administration of HP-ß-cyclodextrins inhibited creatine kinase activity and increased the total sulfhydryl content in kidneys. Here, we demonstrated for the first time that ß-cyclodextrins, M-ß-cyclodextrins, and HP-ß-cyclodextrins cause bioenergetic dysfunction in renal and hepatic tissues. These findings suggest that understanding the balance between cyclodextrins' efficacy and adverse effects is essential for better accepting their use in medicine.


Assuntos
Ciclodextrinas , beta-Ciclodextrinas , Ratos , Animais , beta-Ciclodextrinas/farmacologia , Ciclodextrinas/farmacologia , 2-Hidroxipropil-beta-Ciclodextrina/farmacologia , Metabolismo Energético
4.
J Eur Acad Dermatol Venereol ; 36(8): 1246-1255, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35426183

RESUMO

BACKGROUND: Staging systems for cutaneous squamous cell carcinoma (cSCC) produce inconsistent risk stratification. OBJECTIVE: The aim of this study was to identify further prognostic parameters for better stratification. METHODS: We retrospectively analysed the prognostic significance of clinicopathologic parameters of 230 patients who underwent primary excision of invasive cSCC of the head and neck (n = 115) and non-head and non-neck (n = 115) locations. In addition to known high-risk features, we analysed tumour nest shape, invasion pattern, lymphoid response pattern and tumour budding. RESULTS: On multivariable analysis, lymphovascular invasion (LVI) and high tumour budding predicted worse disease-specific survival, and ulceration, LVI and high tumour budding predicted worse overall survival. Only ulceration was independently associated with risk of nodal metastasis. CONCLUSION: High tumour budding, LVI and ulceration are independently associated with poor outcome in cSCC and may be used to refine cSCC prognostic stratification, which is crucial to optimize clinical decision and to identify patients who are more likely to benefit from more aggressive interventions or clinical trials.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Cutâneas , Carcinoma de Células Escamosas/patologia , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Estadiamento de Neoplasias , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Neoplasias Cutâneas/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço
5.
Respir Res ; 22(1): 107, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33863318

RESUMO

Sarcoidosis and chronic beryllium disease (CBD) are phenocopies, however the latter one has a clear trigger factor that is beryllium exposure. This study analyses single nucleotide polymorphisms (SNPs) in a large cohort for beryllium-exposed persons. SNPs were chosen for their relevance in sarcoidosis. Even though one of largest cohorts of beryllium-exposed persons was analysed, no statistically relevant association between any SNP and CBD could be verified. Notably, some SNPs exhibit inverse OR for beryllium sensitization and CBD with nominally statistical significance, which allows hypothesizing about pathophysiological role of genes for the disease triggering and development.


Assuntos
Beriliose/genética , Berílio/efeitos adversos , Butirofilinas/genética , DNA/genética , Exposição Ocupacional/efeitos adversos , Polimorfismo de Nucleotídeo Único , Beriliose/metabolismo , Butirofilinas/metabolismo , Doença Crônica , Feminino , Humanos , Masculino
6.
Am J Respir Crit Care Med ; 197(2): 225-234, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-28846439

RESUMO

RATIONALE: The etiology of sarcoidosis is unknown, but microbial agents are suspected as triggers. OBJECTIVES: We sought to identify bacterial, fungal, or viral lineages in specimens from patients with sarcoidosis enriched relative to control subjects using metagenomic DNA sequencing. Because DNA from environmental contamination contributes disproportionately to samples with low authentic microbial content, we developed improved methods for filtering environmental contamination. METHODS: We analyzed specimens from subjects with sarcoidosis (n = 93), control subjects without sarcoidosis (n = 72), and various environmental controls (n = 150). Sarcoidosis specimens consisted of two independent sets of formalin-fixed, paraffin-embedded lymph node biopsies, BAL, Kveim reagent, and fresh granulomatous spleen from a patient with sarcoidosis. All specimens were analyzed by bacterial 16S and fungal internal transcribed spacer ribosomal RNA gene sequencing. In addition, BAL was analyzed by shotgun sequencing of fractions enriched for viral particles, and Kveim and spleen were subjected to whole-genome shotgun sequencing. MEASUREMENTS AND MAIN RESULTS: In one tissue set, fungi in the Cladosporiaceae family were enriched in sarcoidosis compared with nonsarcoidosis tissues; in the other tissue set, we detected enrichment of several bacterial lineages in sarcoidosis but not Cladosporiaceae. BAL showed limited enrichment of Aspergillus fungi. Several microbial lineages were detected in Kveim and spleen, including Cladosporium. No microbial lineage was enriched in more than one sample type after correction for multiple comparisons. CONCLUSIONS: Metagenomic sequencing revealed enrichment of microbes in single types of sarcoidosis samples but limited concordance across sample types. Statistical analysis accounting for environmental contamination was essential to avoiding false positives.


Assuntos
DNA Bacteriano/análise , Metagenoma/genética , Microbiota/genética , Sarcoidose/genética , Sarcoidose/microbiologia , Biópsia por Agulha , Estudos de Casos e Controles , Feminino , Humanos , Imuno-Histoquímica , Teste de Kveim , Masculino , Valores de Referência , Sarcoidose/patologia , Sensibilidade e Especificidade , Inclusão do Tecido
7.
Radiology ; 287(3): 993-1002, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29558296

RESUMO

Purpose To examine the effect metabolic burden (tumor and/or cardiac myocyte uptake) has on fluorine 18 fluorodeoxyglucose (FDG) distribution in organs and tissues of interest. Materials and Methods Positron emission tomographic (PET)/computed tomographic (CT) scans at the Ann Arbor Veterans Affairs hospital from January to July 2015 were reviewed. A total of 107 scans (50 patients; mean age, 64.3 years ± 13.2 [standard deviation]) had metabolic tissue burden assessed by using total lesion glycolysis (TLG) obtained from autosegmentation of the tumor and/or cardiac tissue. Standardized uptake value (SUV) and subsequent normalized SUV uptake in target organs and tissues were compared with 436 FDG PET/CT scans previously reported in 229 patients as a function of TLG to describe the effect(s) that metabolic burden has on reference tissue (blood pool, liver, and brain) FDG uptake. Subsequent regression by using linear mixed-effects models was used. If the slope of the regression was significantly (P < .05) different than zero, then an effect from TLG was present. Results There was a negative inverse relationship (P < .0001) between FDG uptake within reference tissues (blood pool, liver, and brain) and TLG in comparison to the study population at similar blood glucose levels. This TLG effect was no longer statistically significant (P > .05) when FDG uptake was normalized to a reference tissue (eg, blood pool or liver). Conclusion Metabolic tissue burden can have a significant effect on SUV measurements for PET imaging. This effect can be mitigated by normalizing FDG uptake to a reference tissue. © RSNA, 2018.


Assuntos
Fluordesoxiglucose F18/farmacocinética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Compostos Radiofarmacêuticos/farmacocinética , Carga Tumoral , Imagem Corporal Total/métodos , Gânglios da Base/metabolismo , Feminino , Fluordesoxiglucose F18/metabolismo , Humanos , Fígado/metabolismo , Masculino , Pessoa de Meia-Idade , Compostos Radiofarmacêuticos/metabolismo , Estudos Retrospectivos
8.
Radiology ; 279(3): 917-24, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26785042

RESUMO

Purpose To assess the feasibility and optimize the accuracy of the multibreath wash-in hyperpolarized helium 3 ((3)He) approach to ventilation measurement by using magnetic resonance (MR) imaging as well as to examine the physiologic differences that this approach reveals among nonsmokers, asymptomatic smokers, and patients with chronic obstructive pulmonary disease (COPD). Materials and Methods All experiments were approved by the local institutional review board and compliant with HIPAA. Informed consent was obtained from all subjects. To measure fractional ventilation, the authors administered a series of identical normoxic hyperpolarized gas breaths to the subject; after each inspiration, an image was acquired during a short breath hold. Signal intensity buildup was fit to a recursive model that regionally solves for fractional ventilation. This measurement was successfully performed in nine subjects: three healthy nonsmokers (one man, two women; mean age, 45 years ± 4), three asymptomatic smokers (three men; mean age, 51 years ± 5), and three patients with COPD (three men; mean age, 59 years ± 5). Repeated measures analysis of variance was performed, followed by post hoc tests with Bonferroni correction, to assess the differences among the three cohorts. Results Whole-lung fractional ventilation as measured with hyperpolarized (3)He in all subjects (mean, 0.24 ± 0.06) showed a strong correlation with global fractional ventilation as measured with a gas delivery device (R(2) = 0.96, P < .001). Significant differences between the means of whole-lung fractional ventilation (F2,10 = 7.144, P = .012) and fractional ventilation heterogeneity (F2,10 = 7.639, P = .010) were detected among cohorts. In patients with COPD, the protocol revealed regions wherein fractional ventilation varied substantially over multiple breaths. Conclusion Multibreath wash-in hyperpolarized (3)He MR imaging of fractional ventilation is feasible in human subjects and demonstrates very good global (whole-lung) precision. Fractional ventilation measurement with this physiologically realistic approach reveals significant differences between patients with COPD and healthy subjects. To minimize error, several sources of potential bias must be corrected when calculating fractional ventilation. (©) RSNA, 2016 Online supplemental material is available for this article.


Assuntos
Hélio/administração & dosagem , Processamento de Imagem Assistida por Computador/métodos , Pulmão/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Doença Pulmonar Obstrutiva Crônica/diagnóstico por imagem , Fumar/fisiopatologia , Adulto , Biomarcadores/análise , Estudos de Casos e Controles , Estudos de Viabilidade , Feminino , Hélio/análise , Humanos , Pulmão/fisiologia , Masculino , Pessoa de Meia-Idade , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Processamento de Sinais Assistido por Computador
9.
Magn Reson Med ; 76(4): 1092-101, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26467179

RESUMO

PURPOSE: This study tested the ability of a multibreath hyperpolarized HP (3) He MRI protocol to increase the accuracy of regional alveolar oxygen tension (PA O2 ) measurements by lessening the influence of gas-flow artifacts. Conventional single-breath PA O2 measurement has been susceptible to error induced by intervoxel gas flow, particularly when used to study subjects with moderate-to-severe chronic obstructive pulmonary disease (COPD). METHODS: Both single-breath and multibreath PA O2 imaging schemes were implemented in seven human subjects (one healthy, three asymptomatic smokers, and three COPD). The number and location of voxels with nonphysiologic PA O2 values generated by intervoxel gas flow were compared between the two protocols. RESULTS: The multibreath scheme resulted in a significantly lower total percentage of nonphysiologic PA O2 values (6.0%) than the single-breath scheme (13.7%) (P = 0.006). PA O2 maps showed several patterns of gas-flow artifacts that were present in the single-breath protocol but mitigated by the multibreath approach. Multibreath imaging also allowed for the analysis of slow-filling areas that presented no signal after a single breath. CONCLUSION: A multibreath approach enhances the accuracy and completeness of noninvasive PA O2 measurement by significantly lessening the proportion of nonphysiologic values generated by intervoxel gas flow. Magn Reson Med 76:1092-1101, 2016. © 2015 Wiley Periodicals, Inc.


Assuntos
Hélio/farmacocinética , Isótopos/farmacocinética , Imageamento por Ressonância Magnética/métodos , Consumo de Oxigênio/fisiologia , Oxigênio/metabolismo , Alvéolos Pulmonares/fisiologia , Troca Gasosa Pulmonar/fisiologia , Mecânica Respiratória/fisiologia , Administração por Inalação , Adulto , Hélio/administração & dosagem , Humanos , Isótopos/administração & dosagem , Masculino , Pessoa de Meia-Idade , Imagem Molecular/métodos , Compostos Radiofarmacêuticos/administração & dosagem , Compostos Radiofarmacêuticos/farmacocinética , Reprodutibilidade dos Testes , Testes de Função Respiratória/métodos , Sensibilidade e Especificidade
10.
Radiographics ; 36(7): 2154-2169, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27494386

RESUMO

Frostbite is a localized cold thermal injury that results from tissue freezing. Frostbite injuries can have a substantial effect on long-term limb function and mobility if not promptly evaluated and treated. Imaging plays a critical role in initial evaluation of frostbite injuries and in monitoring response to treatment. A multimodality approach involving radiography, digital subtraction angiography (DSA), and/or multiphase bone scintigraphy with hybrid single photon emission computed tomography (SPECT)/computed tomography (CT) is often necessary for optimal guidance of frostbite care. Radiographs serve as an initial survey of the affected limb and may demonstrate characteristic findings, depending on the time course and severity of injury. DSA is used to evaluate perfusion of affected soft tissues and identify potential targets for therapeutic intervention. Angiography-directed thrombolysis plays an essential role in tissue preservation and salvage in deep frostbite injuries. Multiphase bone scintigraphy with technetium 99m-labeled diphosphonate provides valuable information regarding the status of tissue viability after initial treatment. The addition of SPECT/CT to multiphase bone scintigraphy enables precise anatomic localization of the level and depth of tissue necrosis before its appearance at physical examination and can help uncover subtle findings that may remain occult at scintigraphy alone. Multiphase bone scintigraphy with SPECT/CT is the modality of choice for prognostication and planning of definitive surgical care of affected limbs. Appropriate use of imaging to direct frostbite care can help limit the effects that these injuries have on limb function and mobility. ©RSNA, 2016.


Assuntos
Angiografia Digital/normas , Congelamento das Extremidades/diagnóstico por imagem , Guias de Prática Clínica como Assunto , Radiologia/normas , Tomografia Computadorizada com Tomografia Computadorizada de Emissão de Fóton Único/normas , Tomografia Computadorizada por Raios X/normas , Diagnóstico Diferencial , Humanos , Imagem Multimodal/normas , Traumatismo Múltiplo/diagnóstico por imagem , Osteonecrose/diagnóstico por imagem , Lesões dos Tecidos Moles/diagnóstico por imagem , Estados Unidos
11.
Radiology ; 277(1): 247-58, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26110668

RESUMO

PURPOSE: To determine whether hyperpolarized helium 3 magnetic resonance (MR) imaging to measure alveolar partial pressure of oxygen (Pao2) shows sufficient test-retest repeatability and between-cohort differences to be used as a reliable technique for detection of alterations in gas exchange in asymptomatic smokers. MATERIALS AND METHODS: The protocol was approved by the local institutional review board and was HIPAA compliant. Informed consent was obtained from all subjects. Two sets of MR images were obtained 10 minutes apart in 25 subjects: 10 nonsmokers (five men, five women; mean ± standard deviation age, 50 years ± 6) and 15 smokers (seven women, eight men; mean age, 50 years ± 8). A mixed-effects model was developed to identify the regional repeatability of Pao2 measurements as an intraclass correlation coefficient. Ten smokers were matched with the 10 nonsmokers on the basis of signal-to-noise ratio (SNR). Three separate models were generated: one for nonsmokers, one for the SNR-matched smokers, and one for the five remaining smokers, who were imaged with a significantly higher SNR. RESULTS: Short-term back-to-back regional reproducibility was assessed by using intraclass correlation coefficients, which were 0.67 and 0.65 for SNR case-matched nonsmokers and smokers, respectively. Repeatability was a strong function of SNR; a 50% increase in SNR in the remaining smokers improved the intraclass correlation coefficient to 0.82. Although repeatability was not significantly different between the SNR-matched cohorts (P = .44), the smoker group showed higher spatial and temporal variability in Pao2. CONCLUSION: The short-term test-retest repeatability of hyperpolarized gas MR imaging of regional Pao2 was good. Asymptomatic smokers exhibited greater spatial and temporal variability in Pao2 than did the nonsmokers, which suggests that this parameter allows detection of small functional alterations associated with smoking.


Assuntos
Imageamento por Ressonância Magnética/métodos , Troca Gasosa Pulmonar , Fumar/fisiopatologia , Adulto , Feminino , Hélio , Humanos , Isótopos , Masculino , Pessoa de Meia-Idade , Oxigênio , Pressão Parcial , Alvéolos Pulmonares , Reprodutibilidade dos Testes , Fatores de Tempo
12.
Radiology ; 274(2): 585-96, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25322340

RESUMO

PURPOSE: To assess the ability of helium 3 ((3)He) magnetic resonance (MR) imaging of regional alveolar partial pressure of oxygen (Pao2) to depict smoking-induced functional alterations and to compare its efficacy to that of current diagnostic techniques. MATERIALS AND METHODS: This study was approved by the local institutional review board and was compliant with HIPAA. All subjects provided informed consent. A total of 43 subjects were separated into three groups: nonsmokers, asymptomatic smokers, and symptomatic smokers. All subjects underwent a Pao2 imaging session followed by clinically standard pulmonary function tests (PFTs), the 6-minute walk test, and St George Respiratory Questionnaire (SGRQ). The whole-lung mean and standard deviation of Pao2 were compared with metrics derived from PFTs, the 6-minute walk test, and the SGRQ. A logistic regression model was developed to identify the predictors of alterations to the lungs of asymptomatic smokers. RESULTS: The whole-lung standard deviation of Pao2 correlated with PFT metrics (forced expiratory volume in 1 second [FEV1]/forced vital capacity [FVC], Pearson r = -0.69, P < .001; percentage predicted FEV1, Pearson r = -0.67, P < .001; diffusing capacity of lung for carbon monoxide [Dlco], Pearson r = -0.45, P = .003), SGRQ score (Pearson r = 0.67, P < .001), and distance walked in 6 minutes (Pearson r = -0.47, P = .002). The standard deviation of Pao2 was significantly higher in asymptomatic smokers than in nonsmokers (change in the standard deviation of Pao2 = 7.59 mm Hg, P = .041) and lower when compared with symptomatic smokers (change in the standard deviation of Pao2 = 10.72 mm Hg, P = .001). A multivariate prediction model containing FEV1/FVC and the standard deviation of Pao2 (as significant predictors of subclinical changes in smokers) and Dlco (as a confounding variable) was formulated. This model resulted in an area under the receiver operating characteristic curve with a significant increase of 29.2% when compared with a prediction model based solely on nonimaging clinical tests. CONCLUSION: The (3)He MR imaging heterogeneity metric (standard deviation of Pao2) enabled the differentiation of all three study cohorts, which indicates that it can depict smoking-related functional alterations in asymptomatic current smokers.


Assuntos
Hélio , Imageamento por Ressonância Magnética/métodos , Oxigênio/fisiologia , Alvéolos Pulmonares/fisiopatologia , Fumar/fisiopatologia , Feminino , Humanos , Isótopos , Masculino , Pessoa de Meia-Idade , Pressão Parcial , Testes de Função Respiratória
13.
J Appl Microbiol ; 118(4): 792-802, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25619119

RESUMO

AIMS: This study aimed to select and validate different methodological strategies to quantify the expression of the virulence genes ascC and ascV by qPCR in Aeromonas salmonicida subsp. salmonicida (Aer. salmonicida). METHODS AND RESULTS: Using the geNorm, Normfinder and BestKeeper algorithms, reference genes for the qPCR were selected based on their in vitro expression stabilities in three Aer. salmonicida strains. Gene amplification efficiency was calculated by Real-time PCR Miner and LinReg PCR programmes, which have not been used previously in the analysis of bacterial gene expression. The expression of the ascC and ascV virulence genes in a virulent Aer. salmonicida strain was evaluated by three quantification models, including single (least or most stable) or three most stable reference genes, combined with constant or specific gene amplification efficiency. The most stable reference genes were gyrB, proC and rpoC, while rpoD and fabD were the least stable. Quantification models showed different expression patterns. CONCLUSIONS: The optimal strategy to quantify mRNA expression was to use a combination of the three algorithms and the quantification model including the three most stable reference genes. Real-time PCR Miner or LinReg PCR were valuable tools to estimate amplification efficiency. SIGNIFICANCE AND IMPACT OF THE STUDY: The methods used in this study gave more reliable expression data using qPCR than previously published methods. The quantification and expression dynamics of virulence genes will contribute to a better understanding of how Aer. salmonicida interacts with its host and the environment, and therefore to the prevention of epizootics due to this pathogen.


Assuntos
Aeromonas salmonicida/genética , Proteínas de Bactérias/genética , Reação em Cadeia da Polimerase em Tempo Real/métodos , Fatores de Virulência/genética , Aeromonas salmonicida/metabolismo , Proteínas de Bactérias/metabolismo , Fatores de Virulência/metabolismo
14.
J Fish Dis ; 38(10): 891-900, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25271952

RESUMO

The metalloendopeptidase AsaP1 is one of the major extracellular virulence factors of A. salmonicida subsp. achromogenes, expressed as a 37-kDa pre-pro-peptide and processed to a 19-kDa active peptide. The aim of this study was to construct mutant strains secreting an AsaP1-toxoid instead of AsaP1-wt, to study virulence of these strains and to test the potency of the AsaP1-toxoid bacterin and the recombinant AsaP1-toxoids to induce protective immunity in Arctic char. Two A. salmonicida mutants were constructed that secrete either AsaP1E294A or AsaP1Y309F . The secreted AsaP1Y309F -toxoid had weak caseinolytic activity and was processed to the 19-kDa peptide, whereas the AsaP1E294A -toxoid was found as a 37-kDa pre-pro-peptide suggesting that AsaP1 is auto-catalytically processed. The LD50 of the AsaP1Y309F -toxoid mutant in Arctic char was significantly higher than that of the corresponding wt strain, and LD50 of the AsaP1E294A -toxoid mutant was comparable with that of an AsaP1-deficient strain. Bacterin based on AsaP1Y309F -toxoid mutant provided significant protection, comparable with that induced by a commercial polyvalent furunculosis vaccine. Detoxification of AsaP1 is very hard, expensive and time consuming. Therefore, an AsaP1-toxoid-secreting mutant is more suitable than the respective wt strain for production of fish bacterins aimed to protect against atypical furunculosis.

15.
J Invertebr Pathol ; 123: 1-5, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25218400

RESUMO

The lesser mealworm, Alphitobius diaperinus, is a serious cosmopolitan pest of commercial poultry facilities because of its involvement in structural damage to poultry houses, reduction in feed conversion efficiency, and transfer of avian and human pathogens. Cry3Aa, Cry3Bb, and Cry8Ca insecticidal proteins of Bacillus thuringiensis are used to control coleopteran larvae. Cadherins localized in the midgut epithelium function as receptors for Cry toxins in lepidopteran, coleopteran, and dipteran insects. Previously, we demonstrated that the truncated cadherin (DvCad1) from Diabrotica virgifera virgifera, which consists of the C-terminal cadherin repeats (CR) 8-10 and expressed in Escherichia coli, enhanced Cry3Aa and Cry3Bb toxicity against several coleopteran species. Here we report that the DvCad1-CR8-10 enhances Cry3Aa, Cry3Bb, and Cry8Ca toxicity to lesser mealworm. Previously, by an enzyme linked immunosorbent microplate assay, we demonstrated that the DvCad1-CR8-10 binds activated-Cry3Aa (11.8 nM), -Cry3Bb (1.4nM), and now report that CR8-10 binds activated-Cry8Ca (5.7 nM) toxin. The extent of Cry toxins enhancement by DvCad1-CR8-10, which ranged from 3.30- to 5.93-fold, may have practical application for lesser mealworm control in preventing avian and human pathogen transfer in poultry facilities.


Assuntos
Proteínas de Bactérias/toxicidade , Endotoxinas/toxicidade , Proteínas Hemolisinas/toxicidade , Proteínas de Insetos/toxicidade , Controle Biológico de Vetores/métodos , Tenebrio , Animais , Toxinas de Bacillus thuringiensis , Besouros , Proteínas de Insetos/metabolismo , Tenebrio/efeitos dos fármacos
16.
Radiographics ; 33(2): 397-418, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23479704

RESUMO

Radioiodine imaging has a well-established role in depicting metastatic disease after thyroidectomy in patients with well-differentiated thyroid cancer. Uptake of radioiodine in thyroid metastases depends on expression of sodium-iodide symporter (NIS) by tumor tissues. However, because radioiodine may also accumulate in normal structures and tissues, it is important to distinguish physiologic radioiodine activity from metastatic disease. Furthermore, secretions that contain radioiodine may also simulate pathologic uptake. A spectrum of physiologic distributions, normal variants, and benign mimics of disease have been described in the literature; yet, even when armed with a comprehensive knowledge of these patterns, interpreting radiologists and nuclear physicians may still encounter diagnostic uncertainty. Single-photon emission computed tomography (SPECT) with integrated computed tomography (CT) is a novel technology that, when applied to diagnostic iodine 123 or iodine 131 ((131)I) radioiodine scintigraphy, may accurately localize and help distinguish benign mimics of disease, with the potential to alter the management plan. SPECT/CT is increasingly being used with radioiodine scintigraphy to evaluate patients with thyroid cancer and shows promise for improving imaging specificity and reducing false-positive results.


Assuntos
Artefatos , Erros de Diagnóstico/prevenção & controle , Aumento da Imagem/métodos , Radioisótopos do Iodo , Neoplasias da Glândula Tireoide/diagnóstico , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Reações Falso-Positivas , Feminino , Humanos , Radioisótopos do Iodo/farmacocinética , Masculino , Pessoa de Meia-Idade , Especificidade de Órgãos , Compostos Radiofarmacêuticos/farmacocinética , Técnica de Subtração , Neoplasias da Glândula Tireoide/metabolismo , Distribuição Tecidual , Adulto Jovem
17.
J Fish Biol ; 82(3): 907-26, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23464551

RESUMO

The ecological effect of prawn trawling on the benthos of the Gulf of Carpentaria, northern Australia, was investigated by examining stomach contents of common demersal fishes incidentally caught as by-catch in the fishery. Fishes were collected from high and low fishing intensity sites in three regions based on vessel monitoring system data. The diets of eight species of benthic fish predators were compared between regions and fishing intensities. A regional effect on diet was evident for seven species. Only one generalist species had no significant difference in diet among the three regions. For the comparisons within each region, five predator species had significantly different diet between high and low fishing intensities in at least one region. Across the three regions, high fishing intensity sites had predators that consumed a greater biomass of crustaceans, molluscs and echinoderms. At low fishing intensity sites, predators had diets comprising a greater biomass of cnidarians and teleosts, and a different assemblage of molluscs, crustaceans and fishes. These changes in diet suggest that there may have been a shift in the structure of the benthic community following intensive fishing. Analysis of predator diets is a useful tool to help identify changes in the benthic community composition after exposure to fishing. This study also provided valuable diet information on a range of abundant generalist benthic predators to improve the ecosystem modelling tools needed to support ecosystem-based fisheries management.


Assuntos
Biota , Pesqueiros/métodos , Peixes/fisiologia , Animais , Austrália , Conservação dos Recursos Naturais , Dieta , Conteúdo Gastrointestinal , Dinâmica Populacional
19.
Clin Exp Allergy ; 42(3): 423-32, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22356143

RESUMO

BACKGROUND: Whilst emerging evidence from animal and cell experiments has shown high-density lipoprotein cholesterol to have anti-inflammatory effects consistent with a protective role in asthma, human studies investigating the relationship of high-density lipoprotein cholesterol with asthma have produced conflicting results. OBJECTIVE: To examine the association between serum lipids among Cypriot children aged 11-12 years and prevalence of asthma at age 15-17 years. METHODS: In 3982 children, we assessed serum lipids, body mass index and maximal oxygen consumption at baseline (2001-2003) and explored associations with respiratory health at follow-up (2007) using multiple logistic regression models. RESULTS: Lower levels of high-density lipoprotein cholesterol at age 11-12 years were found in subjects who reported ever asthma (58.2 vs. 60.0 mg/dL, P = 0.005) and active asthma (57.5 vs. 59.9 mg/dL, P = 0.010) in adolescence, in comparison with their respective reference groups. Total cholesterol, low-density lipoprotein and triglycerides had no association with any of the asthma outcomes. In contrast, with estimated odds ratios of 1.89 (95% CI 1.19-3.00) and 1.89 (95% CI 1.02-3.53), ever asthma and active asthma respectively appeared particularly pronounced among those who at baseline had high-density lipoprotein cholesterol <40 mg/dL, even after adjusting for potential confounders including body mass index and maximal oxygen consumption. CONCLUSIONS & CLINICAL RELEVANCE: Low-serum high-density lipoprotein cholesterol in childhood is associated with an increased risk for asthma in adolescence, suggesting a potential role of this lipoprotein in the pathogenesis of paediatric asthma.


Assuntos
Asma/sangue , Asma/epidemiologia , HDL-Colesterol/sangue , HDL-Colesterol/imunologia , Adolescente , Índice de Massa Corporal , Feminino , Seguimentos , Humanos , Masculino , Aptidão Física , Prevalência
20.
Appl Environ Microbiol ; 78(2): 354-62, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22081566

RESUMO

The Cry proteins produced by Bacillus thuringiensis (Bt) are the most widely used biopesticides effective against a range of crop pests and disease vectors. Like chemical pesticides, development of resistance is the primary threat to the long-term efficacy of Bt toxins. Recently discovered cadherin-based Bt Cry synergists showed the potential to augment resistance management by improving efficacy of Cry toxins. However, the mode of action of Bt Cry synergists is thus far unclear. Here we elucidate the mechanism of cadherin-based Cry toxin synergism utilizing two cadherin peptides, Spodoptera frugiperda Cad (SfCad) and Manduca sexta Cad (MsCad), which differentially enhance Cry1Fa toxicity to Spodoptera frugiperda neonates. We show that differential SfCad- and MsCad-mediated protection of Cry1Fa toxin in the Spodoptera frugiperda midgut correlates with differential Cry1Fa toxicity enhancement. Both peptides exhibited high affinity for Cry1Fa toxin and an increased rate of Cry1Fa-induced pore formation in S. frugiperda. However, only SfCad bound the S. frugiperda brush border membrane vesicle and more effectively prolonged the stability of Cry1Fa toxin in the gut, explaining higher Cry1Fa enhancement by this peptide. This study shows that cadherin fragments may enhance B. thuringiensis toxicity by at least two different mechanisms or a combination thereof: (i) protection of Cry toxin from protease degradation in the insect midgut and (ii) enhancement of pore-forming ability of Cry toxin.


Assuntos
Proteínas de Bactérias/toxicidade , Caderinas/antagonistas & inibidores , Endotoxinas/toxicidade , Proteínas Hemolisinas/toxicidade , Inibidores de Proteases/toxicidade , Spodoptera/efeitos dos fármacos , Animais , Toxinas de Bacillus thuringiensis , Sinergismo Farmacológico , Trato Gastrointestinal/efeitos dos fármacos , Trato Gastrointestinal/enzimologia , Humanos , Larva/efeitos dos fármacos , Manduca/efeitos dos fármacos
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