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1.
Ann Rheum Dis ; 81(2): 232-236, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34407928

RESUMO

OBJECTIVES: This study aimed to determine the prevalence of ultrasound-detected tendon abnormalities in healthy subjects (HS) across the age range. METHODS: Adult HS (age 18-80 years) were recruited in 23 international Outcome Measures in Rheumatology ultrasound centres and were clinically assessed to exclude inflammatory diseases or overt osteoarthritis before undergoing a bilateral ultrasound examination of digit flexors (DFs) 1-5 and extensor carpi ulnaris (ECU) tendons to detect the presence of tenosynovial hypertrophy (TSH), tenosynovial power Doppler (TPD) and tenosynovial effusion (TEF), usually considered ultrasound signs of inflammatory diseases. A comparison cohort of patients with rheumatoid arthritis (RA) was taken from the Birmingham Early Arthritis early arthritis inception cohort. RESULTS: 939 HS and 144 patients with RA were included. The majority of HS (85%) had grade 0 for TSH, TPD and TEF in all DF and ECU tendons examined. There was a statistically significant difference in the proportion of TSH and TPD involvement between HS and subjects with RA (HS vs RA p<0.001). In HS, there was no difference in the presence of ultrasound abnormalities between age groups. CONCLUSIONS: Ultrasound-detected TSH and TPD abnormalities are rare in HS and can be regarded as markers of active inflammatory disease, especially in newly presenting RA.


Assuntos
Tendões/diagnóstico por imagem , Tendões/patologia , Tenossinovite/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Feminino , Voluntários Saudáveis , Humanos , Hipertrofia/diagnóstico por imagem , Hipertrofia/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Tenossinovite/diagnóstico por imagem , Ultrassonografia , Adulto Jovem
2.
Europace ; 24(3): 390-399, 2022 03 02.
Artigo em Inglês | MEDLINE | ID: mdl-34480548

RESUMO

AIMS: To determine if adapting the ablation index (AI) to the left atrial wall thickness (LAWT), which is a determinant of lesion transmurality, is feasible, effective, and safe during paroxysmal atrial fibrillation (PAF) ablation. METHODS AND RESULTS: Consecutive patients referred for PAF first ablation. Left atrial wall thickness three-dimensional maps were obtained from multidetector computed tomography and integrated into the CARTO navigation system. Left atrial wall thickness was categorized into 1 mm layers and AI was titrated to the LAWT. The ablation line was personalized to avoid thicker regions. Primary endpoints were acute efficacy and safety, and freedom from atrial fibrillation (AF) recurrences. Follow-up (FU) was scheduled at 1, 3, 6, and every 6 months thereafter. Ninety patients [60 (67%) male, age 58 ± 13 years] were included. Mean LAWT was 1.25 ± 0.62 mm. Mean AI was 366 ± 26 on the right pulmonary veins with a first-pass isolation in 84 (93%) patients and 380 ± 42 on the left pulmonary veins with first-pass in 87 (97%). Procedure time was 59 min (49-66); radiofrequency (RF) time 14 min (12.5-16); and fluoroscopy time 0.7 min (0.5-1.4). No major complication occurred. Eighty-four out of 90 (93.3%) patients were free of recurrence after a mean FU of 16 ± 4 months. CONCLUSION: Personalized AF ablation, adapting the AI to LAWT allowed pulmonary vein isolation with low RF delivery, fluoroscopy, and procedure time while obtaining a high rate of first-pass isolation, in this patient population. Freedom from AF recurrences was as high as in more demanding ablation protocols. A multicentre trial is ongoing to evaluate reproducibility of these results.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Veias Pulmonares , Idoso , Fibrilação Atrial/diagnóstico por imagem , Fibrilação Atrial/cirurgia , Ablação por Cateter/efeitos adversos , Ablação por Cateter/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Veias Pulmonares/diagnóstico por imagem , Veias Pulmonares/cirurgia , Recidiva , Reprodutibilidade dos Testes , Resultado do Tratamento
3.
Pacing Clin Electrophysiol ; 44(5): 824-834, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33742716

RESUMO

BACKGROUND: Left atrial wall thickness (LAWT) has been related to pulmonary vein (PV) reconnections after atrial fibrillation (AF) ablation. The aim was to integrate 3D-LAWT maps in the navigation system and analyze the relationship with local reconnection sites during AF-redo procedures. METHODS: Consecutive patients referred for AF-redo ablation were included. Procedure was performed using a single catheter technique. LAWT maps obtained from multidetector computerized tomography (MDCT) were imported into the navigation system. LAWT of the circumferential PV line, the reconnected segment and the reconnected point, were analyzed. RESULTS: Sixty patients [44 (73%) male, age 61 ± 10 years] were included. All reconnected veins were isolated using a single catheter technique with 55 min (IQR 47-67) procedure time and 75 s (IQR 50-120) fluoroscopy time. Mean LAWT of the circumferential PV line was 1.46 ± 0.22 mm. The reconnected segment was thicker than the rest of segments of the circumferential PV line (2.05 + 0.86 vs. 1.47 + 0.76, p < .001 for the LPVs; 1.55 + 0.57 vs. 1.27 + 0.57, p < .001 for the RPVs). Mean reconnection point wall thickness (WT) was at the 82nd percentile of the circumferential line in the LPVs and at the 82nd percentile in the RPVs. CONCLUSION: A single catheter technique is feasible and efficient for AF-redo procedures. Integrating the 3D-LAWT map into the navigation system allows a direct periprocedural estimation of the WT at any point of the LA. Reconnection points were more frequently present in thicker segments of the PV line. The use of 3D-LAWT maps can facilitate reconnection point identification during AF-redo ablation.


Assuntos
Fibrilação Atrial/cirurgia , Ablação por Cateter , Átrios do Coração/anatomia & histologia , Átrios do Coração/diagnóstico por imagem , Veias Pulmonares/cirurgia , Tomografia Computadorizada por Raios X , Fibrilação Atrial/diagnóstico por imagem , Feminino , Fluoroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Veias Pulmonares/diagnóstico por imagem , Recidiva , Reoperação
4.
BMC Cancer ; 20(1): 447, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32429869

RESUMO

BACKGROUND: Sex is recognized as a significant determinant of outcome among glioblastoma patients, but the relative prognostic importance of glioblastoma features has not been thoroughly explored for sex differences. METHODS: Combining multi-modal MR images, biomathematical models, and patient clinical information, this investigation assesses which pretreatment variables have a sex-specific impact on the survival of glioblastoma patients (299 males and 195 females). RESULTS: Among males, tumor (T1Gd) radius was a predictor of overall survival (HR = 1.027, p = 0.044). Among females, higher tumor cell net invasion rate was a significant detriment to overall survival (HR = 1.011, p < 0.001). Female extreme survivors had significantly smaller tumors (T1Gd) (p = 0.010 t-test), but tumor size was not correlated with female overall survival (p = 0.955 CPH). Both male and female extreme survivors had significantly lower tumor cell net proliferation rates than other patients (M p = 0.004, F p = 0.001, t-test). CONCLUSION: Despite similar distributions of the MR imaging parameters between males and females, there was a sex-specific difference in how these parameters related to outcomes.


Assuntos
Neoplasias Encefálicas/mortalidade , Glioblastoma/mortalidade , Imageamento por Ressonância Magnética/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/terapia , Criança , Feminino , Seguimentos , Glioblastoma/patologia , Glioblastoma/terapia , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Prognóstico , Estudos Retrospectivos , Fatores Sexuais , Taxa de Sobrevida , Adulto Jovem
5.
J Therm Biol ; 49-50: 66-73, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25774028

RESUMO

Incubation temperature is an important aspect in terms of biological performance among crocodiles, and several controlled experiments have demonstrated a significant relationship between incubation temperature, success in hatching and survival of hatchlings. However, a few studies have tested these relationships in the wild. The objective of this study was to determine the relationship of nest characteristics and environment (hatch year, nest basal area and height, clutch size, distance to shore line, and vegetation cover), to incubation temperature and hatching success among Morelet's crocodile (Crocodylus moreletii). The study was carried out during the nesting seasons of Morelet's crocodile, from 2007 to 2009 in the Laguna de Las Ilusiones, an urban lake located in Villahermosa, Tabasco, Mexico. We physically characterized 18 nests and inserted a temperature data logger in each nest chamber. At the end of the nesting season and prior to hatching, we recovered the crocodile eggs and data loggers and calculated hatching success, under laboratory conditions. We related the environmental variables of the nest with the mean and fluctuation (standard deviation) of nest temperature, using linear models. We also related the environmental variables affecting the nest, to mean nest temperature and fluctuation in incubation temperature and to hatching success, using linear models. Although we found differences in incubation temperature between nests, mean incubation temperature did not differ between years, but there were differences in nest thermal fluctuation between years. The mean incubation temperature for 11 nests (61.1%) was lower than the suggested Female-Male pivotal temperature (producing 50% of each sex) for this species, and all hatchlings obtained were males. There were no differences in clutch size between years, but hatching success varied. Our study indicates that hatching success depends on certain environmental variables and nest conditions to which the eggs are subjected, including season, nest size and clutch size. We also discuss the importance of the fluctuation of incubation temperature on hatching success and sex determination.


Assuntos
Jacarés e Crocodilos/crescimento & desenvolvimento , Comportamento de Nidação , Jacarés e Crocodilos/fisiologia , Animais , Regulação da Temperatura Corporal , Tamanho da Ninhada , Feminino , Lagos , Masculino , México , Dinâmica Populacional , Temperatura
6.
PLoS One ; 19(4): e0299267, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38568950

RESUMO

BACKGROUND AND OBJECTIVE: Glioblastoma (GBM) is one of the most aggressive and lethal human cancers. Intra-tumoral genetic heterogeneity poses a significant challenge for treatment. Biopsy is invasive, which motivates the development of non-invasive, MRI-based machine learning (ML) models to quantify intra-tumoral genetic heterogeneity for each patient. This capability holds great promise for enabling better therapeutic selection to improve patient outcome. METHODS: We proposed a novel Weakly Supervised Ordinal Support Vector Machine (WSO-SVM) to predict regional genetic alteration status within each GBM tumor using MRI. WSO-SVM was applied to a unique dataset of 318 image-localized biopsies with spatially matched multiparametric MRI from 74 GBM patients. The model was trained to predict the regional genetic alteration of three GBM driver genes (EGFR, PDGFRA and PTEN) based on features extracted from the corresponding region of five MRI contrast images. For comparison, a variety of existing ML algorithms were also applied. Classification accuracy of each gene were compared between the different algorithms. The SHapley Additive exPlanations (SHAP) method was further applied to compute contribution scores of different contrast images. Finally, the trained WSO-SVM was used to generate prediction maps within the tumoral area of each patient to help visualize the intra-tumoral genetic heterogeneity. RESULTS: WSO-SVM achieved 0.80 accuracy, 0.79 sensitivity, and 0.81 specificity for classifying EGFR; 0.71 accuracy, 0.70 sensitivity, and 0.72 specificity for classifying PDGFRA; 0.80 accuracy, 0.78 sensitivity, and 0.83 specificity for classifying PTEN; these results significantly outperformed the existing ML algorithms. Using SHAP, we found that the relative contributions of the five contrast images differ between genes, which are consistent with findings in the literature. The prediction maps revealed extensive intra-tumoral region-to-region heterogeneity within each individual tumor in terms of the alteration status of the three genes. CONCLUSIONS: This study demonstrated the feasibility of using MRI and WSO-SVM to enable non-invasive prediction of intra-tumoral regional genetic alteration for each GBM patient, which can inform future adaptive therapies for individualized oncology.


Assuntos
Glioblastoma , Humanos , Glioblastoma/diagnóstico por imagem , Glioblastoma/genética , Glioblastoma/patologia , Medicina de Precisão , Heterogeneidade Genética , Imageamento por Ressonância Magnética/métodos , Algoritmos , Aprendizado de Máquina , Máquina de Vetores de Suporte , Receptores ErbB/genética
7.
Radiology ; 269(2): 577-84, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23801778

RESUMO

PURPOSE: To estimate at-risk and salvaged myocardium by using gated single photon emission computed tomography (SPECT) myocardial perfusion imaging after acute myocardial infarction (AMI). MATERIALS AND METHODS: The study was approved by the hospital's Ethical Committee on Clinical Trials (trial register number, PR(HG)36/2000), and all patients gave informed consent. Forty patients (mean age, 61.78 years; eight women) with a first AMI underwent two gated SPECT examinations--one before percutaneous coronary intervention (PCI) and one 4-5 weeks after PCI. Myocardium at risk was estimated by assessing the perfusion defect at the first gated SPECT examination, and salvaged myocardium was estimated by assessing the risk area minus necrosis at the second examination. Myocardium at risk was estimated by determining the discordance between the areas of left ventricular (LV) wall motion and perfusion at the second examination. Concordance between tests was analyzed by means of linear regression analysis, the Pearson correlation, the intraclass correlation coefficient, and Bland-Altman analysis. RESULTS: An improvement in perfusion, wall motion, wall thickening, and LV ejection fraction (P < .001) was observed at 1 month. At 1 month, the area with abnormal wall motion was greater than the area of altered perfusion (35.47 vs 23.1 cm(2); P = .007). The extent of myocardium at risk estimated from this discordance correlated well with myocardium at risk measured at the first gated SPECT examination and with salvaged myocardium between both studies (Pearson correlation: 0.78 and 0.6, respectively). Concordance for correct classification of patients with salvaged myocardium of 50% or greater was 83% (κ = 0.65). CONCLUSION: Myocardial perfusion gated SPECT performed 1 month after early PCI in a first AMI provides potentially useful information on at-risk and salvaged myocardium. SUPPLEMENTAL MATERIAL: http://radiology.rsna.org/lookup/suppl/doi:10.1148/radiol.13122324/-/DC1.


Assuntos
Infarto do Miocárdio/diagnóstico por imagem , Imagem de Perfusão do Miocárdio/métodos , Tomografia Computadorizada de Emissão de Fóton Único , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Medição de Risco , Tomografia Computadorizada de Emissão de Fóton Único/métodos
8.
Eur J Nucl Med Mol Imaging ; 40(8): 1181-9, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23674208

RESUMO

BACKGROUND: The objective of this study was to investigate the impact of clinical, electrocardiographic and stress testing variables in predicting hard cardiac events (HE) and coronary revascularization (CR) in patients with normal stress-rest gated SPECT. MATERIALS AND METHODS: Included in the study were 2,004 patients (63.5 ± 12.5 years, 41.6% men) with normal myocardial perfusion and left ventricular ejection fraction (LVEF) >50% on gated SPECT who were followed for HE (cardiovascular death or acute myocardial infarction) and CR. RESULTS: During a follow-up of 4.3 ± 2.4 years, 33 patients (1.6 %; 0.4%/year) had HE and 50 patients (2.5%; 0.6%/year) underwent CR. In a univariate analysis, age ≥65 years, insulin-dependent diabetes mellitus (IDDM), left bundle branch block (LBBB), and pharmacological stress were associated with HE. Independent predictors of HE were age ≥65 years (p < 0.001; HR 6.9), IDDM (p = 0.014; HR 3.4), and LBBB (p = 0.002; HR 4.6). In the univariate analysis, male gender, LVEF, known coronary artery disease (CAD), LBBB, and a positive stress test were associated with CR. Independent predictors of CR were known CAD (p = 0.016; HR 2.1), and a positive stress test (p = 0.006; HR 2.3). CONCLUSION: Age ≥65 years, IDDM, and LBBB are HE-independent predictors in patients with normal myocardial perfusion and normal LVEF on gated SPECT. The presence of known CAD or a positive stress test significantly increases the probability of CR during follow-up.


Assuntos
Tomografia Computadorizada por Emissão de Fóton Único de Sincronização Cardíaca , Teste de Esforço , Infarto do Miocárdio/diagnóstico , Imagem de Perfusão do Miocárdio , Revascularização Miocárdica , Função Ventricular , Idoso , Eletrocardiografia , Feminino , Ventrículos do Coração/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Sístole
9.
medRxiv ; 2023 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-37503239

RESUMO

BACKGROUND: Glioblastoma is an extraordinarily heterogeneous tumor, yet the current treatment paradigm is a "one size fits all" approach. Hundreds of glioblastoma clinical trials have been deemed failures because they did not extend median survival, but these cohorts are comprised of patients with diverse tumors. Current methods of assessing treatment efficacy fail to fully account for this heterogeneity. METHODS: Using an image-based modeling approach, we predicted T-cell abundance from serial MRIs of patients enrolled in the dendritic cell (DC) vaccine clinical trial. T-cell predictions were quantified in both the contrast-enhancing and non-enhancing regions of the imageable tumor, and changes over time were assessed. RESULTS: A subset of patients in a DC vaccine clinical trial, who had previously gone undetected, were identified as treatment responsive and benefited from prolonged survival. A mere two months after initial vaccine administration, responsive patients had a decrease in model-predicted T-cells within the contrast-enhancing region, with a simultaneous increase in the T2/FLAIR region. CONCLUSIONS: In a field that has yet to see breakthrough therapies, these results highlight the value of machine learning in enhancing clinical trial assessment, improving our ability to prospectively prognosticate patient outcomes, and advancing the pursuit towards individualized medicine.

10.
Nat Commun ; 14(1): 6066, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770427

RESUMO

Sampling restrictions have hindered the comprehensive study of invasive non-enhancing (NE) high-grade glioma (HGG) cell populations driving tumor progression. Here, we present an integrated multi-omic analysis of spatially matched molecular and multi-parametric magnetic resonance imaging (MRI) profiling across 313 multi-regional tumor biopsies, including 111 from the NE, across 68 HGG patients. Whole exome and RNA sequencing uncover unique genomic alterations to unresectable invasive NE tumor, including subclonal events, which inform genomic models predictive of geographic evolution. Infiltrative NE tumor is alternatively enriched with tumor cells exhibiting neuronal or glycolytic/plurimetabolic cellular states, two principal transcriptomic pathway-based glioma subtypes, which respectively demonstrate abundant private mutations or enrichment in immune cell signatures. These NE phenotypes are non-invasively identified through normalized K2 imaging signatures, which discern cell size heterogeneity on dynamic susceptibility contrast (DSC)-MRI. NE tumor populations predicted to display increased cellular proliferation by mean diffusivity (MD) MRI metrics are uniquely associated with EGFR amplification and CDKN2A homozygous deletion. The biophysical mapping of infiltrative HGG potentially enables the clinical recognition of tumor subpopulations with aggressive molecular signatures driving tumor progression, thereby informing precision medicine targeting.


Assuntos
Produtos Biológicos , Neoplasias Encefálicas , Glioma , Imageamento por Ressonância Magnética Multiparamétrica , Humanos , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patologia , Homozigoto , Deleção de Sequência , Glioma/diagnóstico por imagem , Glioma/genética , Glioma/patologia , Imageamento por Ressonância Magnética/métodos
11.
PLoS One ; 18(12): e0287767, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38117803

RESUMO

Brain cancers pose a novel set of difficulties due to the limited accessibility of human brain tumor tissue. For this reason, clinical decision-making relies heavily on MR imaging interpretation, yet the mapping between MRI features and underlying biology remains ambiguous. Standard (clinical) tissue sampling fails to capture the full heterogeneity of the disease. Biopsies are required to obtain a pathological diagnosis and are predominantly taken from the tumor core, which often has different traits to the surrounding invasive tumor that typically leads to recurrent disease. One approach to solving this issue is to characterize the spatial heterogeneity of molecular, genetic, and cellular features of glioma through the intraoperative collection of multiple image-localized biopsy samples paired with multi-parametric MRIs. We have adopted this approach and are currently actively enrolling patients for our 'Image-Based Mapping of Brain Tumors' study. Patients are eligible for this research study (IRB #16-002424) if they are 18 years or older and undergoing surgical intervention for a brain lesion. Once identified, candidate patients receive dynamic susceptibility contrast (DSC) perfusion MRI and diffusion tensor imaging (DTI), in addition to standard sequences (T1, T1Gd, T2, T2-FLAIR) at their presurgical scan. During surgery, sample anatomical locations are tracked using neuronavigation. The collected specimens from this research study are used to capture the intra-tumoral heterogeneity across brain tumors including quantification of genetic aberrations through whole-exome and RNA sequencing as well as other tissue analysis techniques. To date, these data (made available through a public portal) have been used to generate, test, and validate predictive regional maps of the spatial distribution of tumor cell density and/or treatment-related key genetic marker status to identify biopsy and/or treatment targets based on insight from the entire tumor makeup. This type of methodology, when delivered within clinically feasible time frames, has the potential to further inform medical decision-making by improving surgical intervention, radiation, and targeted drug therapy for patients with glioma.


Assuntos
Neoplasias Encefálicas , Glioma , Humanos , Imagem de Tensor de Difusão , Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/genética , Glioma/diagnóstico por imagem , Glioma/genética , Glioma/patologia , Imageamento por Ressonância Magnética/métodos , Biópsia , Encéfalo/patologia , Mapeamento Encefálico
12.
J Nucl Cardiol ; 19(3): 515-23, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22434359

RESUMO

OBJECTIVES: To assess the significance of a paradoxical pattern (PP) (greater tracer uptake during stress than at rest) on gated myocardial perfusion SPECT in myocardial regions with myocardial necrosis. METHODS: A review of 1,764 consecutive stress-rest myocardial perfusion SPECT studies in patients with prior myocardial infarction (MI) was conducted. Of these, 117 patients (6.6%) with a PP corresponding to a region with myocardial necrosis were identified. An assessment of perfusion, contractility, wall thickening, scintigraphic criteria for viability, and the characteristics of the culprit artery in regions with a PP was performed. RESULTS: Of the 160 regions with necrosis, 125 (75%) had a PP: 67 in the anterior region and 58 in the inferior-lateral region. In the PP group, the average tracer activity of defects during stress was significantly higher than at rest (P < .0001). Ninety-three (86.6%) out of 110 PP segments without scintigraphic criteria of viability at rest met viability criteria on stress imaging. The artery supplying regions with a PP was patent in 88% of cases. In the remaining patients it was occluded, although collateral circulation was always present. CONCLUSIONS: In scintigraphic segments corresponding to regions with infarction and PP, a mixture of viable and well perfused myocardium was observed. In most cases, the vessel that supplied the region with PP was either patent, or when the artery was occluded, there was evident collateral circulation.


Assuntos
Técnicas de Imagem de Sincronização Cardíaca/estatística & dados numéricos , Infarto do Miocárdio/diagnóstico , Infarto do Miocárdio/epidemiologia , Imagem de Perfusão do Miocárdio/estatística & dados numéricos , Compostos Organofosforados , Compostos de Organotecnécio , Tomografia Computadorizada de Emissão de Fóton Único/estatística & dados numéricos , Idoso , Comorbidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Necrose/diagnóstico por imagem , Prevalência , Compostos Radiofarmacêuticos , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Sensibilidade e Especificidade , Espanha/epidemiologia
13.
Arch Environ Contam Toxicol ; 62(3): 445-54, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22002785

RESUMO

Effects of endocrine disruptors on reproductive variables of top predators, such as alligators and crocodiles, have long been cited. Due to their long life span, these predators provide us with historic contaminant annals. In this study we tried to test whether lifestyle (free-ranging vs. farm animals) and reproductive age of Morelet's crocodiles in Campeche, Mexico, affect the bioaccumulation of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs). Subsequently, we tested to see whether their concentration was related to steroid hormones (testosterone and estradiol-17ß) levels once normal cyclic hormone variation and reproductive age had been taken into account. From the group of contaminants considered (analyzed as families), only frequency of hexachlorocyclohexanes (∑HCH) and ∑PCB permitted analyses. Whereas there was a greater concentration of ∑HCH bioaccumulated by free-ranging crocodiles, ∑PCB was found in equal quantities in free-ranging and farm animals. No difference was observed in relation to reproductive age for any of the contaminants. However, ∑PCB concentrations were related to testosterone levels among female crocodiles. This androgenic effect of ∑PCB has not been reported previously. Because testosterone promotes aggressive behavior in vertebrates, excessive aggression during the estrous season, or when female crocodiles should be caring for their young, could result in reproductive failure in Morelet's crocodiles and potential long-term decline of the population.


Assuntos
Jacarés e Crocodilos/metabolismo , Hormônios Esteroides Gonadais/metabolismo , Poluentes Químicos da Água/metabolismo , Animais , Disruptores Endócrinos/metabolismo , Disruptores Endócrinos/toxicidade , Monitoramento Ambiental , Feminino , Hidrocarbonetos Clorados/metabolismo , Hidrocarbonetos Clorados/toxicidade , Masculino , México , Praguicidas/metabolismo , Praguicidas/toxicidade , Bifenilos Policlorados/metabolismo , Bifenilos Policlorados/toxicidade , Poluentes Químicos da Água/toxicidade , Poluição Química da Água/estatística & dados numéricos
14.
Am J Emerg Med ; 29(6): 613-7, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20825842

RESUMO

Parenteral anticoagulation is a cornerstone in the management of venous and arterial thrombosis. Unfractionated heparin has a wide dose/response relationship, requiring frequent and troublesome laboratorial follow-up. Because of all these factors, low-molecular-weight heparin use has been increasing. Inadequate dosage has been pointed out as a potential problem because the use of subjectively estimated weight instead of real measured weight is common practice in the emergency department (ED). To evaluate the impact of inadequate weight estimation on enoxaparin dosage, we investigated the adequacy of anticoagulation of patients in a tertiary ED where subjective weight estimation is common practice. We obtained the estimated, informed, and measured weight of 28 patients in need of parenteral anticoagulation. Basal and steady-state (after the second subcutaneous shot of enoxaparin) anti-Xa activity was obtained as a measure of adequate anticoagulation. The patients were divided into 2 groups according the anticoagulation adequacy. From the 28 patients enrolled, 75% (group 1, n = 21) received at least 0.9 mg/kg per dose BID and 25% (group 2, n = 7) received less than 0.9 mg/kg per dose BID of enoxaparin. Only 4 (14.3%) of all patients had anti-Xa activity less than the inferior limit of the therapeutic range (<0.5 UI/mL), all of them from group 2. In conclusion, when weight estimation was used to determine the enoxaparin dosage, 25% of the patients were inadequately anticoagulated (anti-Xa activity <0.5 UI/mL) during the initial crucial phase of treatment.


Assuntos
Anticoagulantes/administração & dosagem , Peso Corporal , Enoxaparina/administração & dosagem , Heparina de Baixo Peso Molecular/administração & dosagem , Trombose/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Distribuição de Qui-Quadrado , Serviço Hospitalar de Emergência , Feminino , Humanos , Injeções Subcutâneas , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Estatísticas não Paramétricas
15.
Neurooncol Adv ; 2(1): vdaa085, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32864609

RESUMO

BACKGROUND: Accurate assessments of patient response to therapy are a critical component of personalized medicine. In glioblastoma (GBM), the most aggressive form of brain cancer, tumor growth dynamics are heterogenous across patients, complicating assessment of treatment response. This study aimed to analyze days gained (DG), a burgeoning model-based dynamic metric, for response assessment in patients with recurrent GBM who received bevacizumab-based therapies. METHODS: DG response scores were calculated using volumetric tumor segmentations for patients receiving bevacizumab with and without concurrent cytotoxic therapy (N = 62). Kaplan-Meier and Cox proportional hazards analyses were implemented to examine DG prognostic relationship to overall (OS) and progression-free survival (PFS) from the onset of treatment for recurrent GBM. RESULTS: In patients receiving concurrent bevacizumab and cytotoxic therapy, Kaplan-Meier analysis showed significant differences in OS and PFS at DG cutoffs consistent with previously identified values from newly diagnosed GBM using T1-weighted gadolinium-enhanced magnetic resonance imaging (T1Gd). DG scores for bevacizumab monotherapy patients only approached significance for PFS. Cox regression showed that increases of 25 DG on T1Gd imaging were significantly associated with a 12.5% reduction in OS hazard for concurrent therapy patients and a 4.4% reduction in PFS hazard for bevacizumab monotherapy patients. CONCLUSION: DG has significant meaning in recurrent therapy as a metric of treatment response, even in the context of anti-angiogenic therapies. This provides further evidence supporting the use of DG as an adjunct response metric that quantitatively connects treatment response and clinical outcomes.

16.
J Nucl Cardiol ; 16(2): 212-21, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19159990

RESUMO

BACKGROUND: There are no extensive series in which risk stratification of patients with ischemic cardiomyopathy (IC) is based on their rest and exercise and scintigraphic characteristics. The purpose of our study was to analyze rest and exercise myocardial perfusion-gated SPECT variables for prognosis in patients with ischemic IC. METHODS AND RESULTS: Prospective cohort study. A study was performed in 167 patients with IC who consecutively underwent rest myocardial perfusion-gated SPECT. In addition, stress SPECT was performed on 137 of these patients. During an average follow-up of 2.3 +/- 1.2 years, cardiac mortality (CM) was 17.4%. Independent predictors of CM in rest-gated SPECT were the positive criteria for myocardial viability (P = 0.027; Hazard risk, HR: 5.1; 95% CI: 1.2-21.4). In the 137 patients who underwent stress-gated SPECT, predictors were scintigraphic criteria for viability plus ischemia (P = 0.026; HR: 3.6; 95% CI: 1.16-11.2) and exercise duration < or = 5 minutes (P = 0.04; HR: 2.7; 95% CI: 1.01-7.36). Coronary angiography variables, performed in 111 patients, did not significantly modify the prognostic value of non-invasive testing. CONCLUSION: Myocardial perfusion-gated SPECT improves prognostic stratification of patients with IC.


Assuntos
Tomografia Computadorizada por Emissão de Fóton Único de Sincronização Cardíaca/métodos , Cardiomiopatias/diagnóstico por imagem , Cardiomiopatias/mortalidade , Insuficiência Cardíaca/diagnóstico por imagem , Insuficiência Cardíaca/mortalidade , Isquemia Miocárdica/diagnóstico por imagem , Isquemia Miocárdica/mortalidade , Idoso , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Prognóstico , Medição de Risco/métodos , Fatores de Risco , Espanha/epidemiologia , Análise de Sobrevida , Taxa de Sobrevida
17.
J Nucl Cardiol ; 15(2): 225-31, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18371594

RESUMO

BACKGROUND: A divergent pattern (DP) of the left ventricle (LV) is an expression of apical remodeling in myocardial perfusion gated single-photon emission computed tomography (SPECT) of patients with ischemic cardiomyopathy (ICM). METHODS AND RESULTS: We consecutively studied 156 patients (mean age, 63 years; 24 women) with ICM (LV ejection fraction, < or =40%) using gated SPECT and technetium-labeled agents. Apical remodeling was considered to exist when a DP was observed. Apical remodeling was noted in 30% of patients, all of whom had a history of anterior myocardial infarction. A divergent pattern was observed more frequently in younger patients and in those with ST-segment elevation on their electrocardiograms. The longer the interval between the infarction and the performance of gated SPECT, the more prevalent were the LV dilatation and DP. A divergent pattern was associated with cardiac death and heart failure only in patients with scintigraphic criteria for myocardial viability. CONCLUSIONS: A divergent pattern in gated SPECT, as an expression of apical remodeling, can be observed in up to a third of patients with ICM, all with a history of anterior infarction. The longer the time between the infarction and the gated SPECT, the more prevalent the LV dilatation becomes. Apical remodeling is a variable predicts mortality in patients with scintigraphic criteria for viability.


Assuntos
Cardiomiopatias/diagnóstico por imagem , Imagem do Acúmulo Cardíaco de Comporta/métodos , Isquemia Miocárdica/diagnóstico por imagem , Tomografia Computadorizada de Emissão de Fóton Único/métodos , Disfunção Ventricular Esquerda/diagnóstico por imagem , Remodelação Ventricular , Cardiomiopatias/complicações , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Isquemia Miocárdica/complicações , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Disfunção Ventricular Esquerda/complicações
18.
Rev. bras. entomol ; 67(spe): e20230044, 2023. graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1521744

RESUMO

ABSTRACT A new antlion species, Tyttholeon froehlichi Tavares, Marquez and Contreras sp. n., is described from the Baja California Peninsula, Mexico, an area biogeographically significant for its high number of endemic species. Previously monotypic, Tyttholeon Adams now comprises two Nearctic species. Three of the four genera within the formerly recognized tribe Gnopholeontini and their respective species, all present in the Peninsula of Baja California (Gnopholeon barberi Currie, G. delicatulus Currie, G. zapotecus Stange, Menkeleon bellulus Banks, and Tyttholeon puerilis Adams), are herein diagnosed, illustrated, and have their distribution updated and analyzed. A taxonomic key is provided for Tyttholeon.

19.
J Rheumatol ; 45(8): 1085-1092, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29657147

RESUMO

OBJECTIVE: To assess 5-year safety, tolerability, and efficacy of subcutaneous (SC) abatacept (ABA) in methotrexate (MTX)-refractory patients with rheumatoid arthritis (RA). METHODS: The Abatacept Comparison of sub[QU]cutaneous versus intravenous in Inadequate Responders to methotrexatE (ACQUIRE) phase IIIb, randomized, double-dummy, multinational trial compared efficacy and safety of SC and intravenous (IV) ABA in patients with RA. In the initial 6-month double-blind (DB) period, patients received IV or SC ABA, plus MTX, and in the subsequent open-label longterm extension (LTE) period, all patients received SC ABA (125 mg/wk). The final 5-year safety, tolerability, and efficacy analyses are reported. RESULTS: Of 1385 patients who completed the DB period, 1372 entered LTE and 945 (68.8%) completed ≥ 5 years of treatment. During LTE, 97 (7.1%) patients discontinued treatment because of an adverse event (AE). Incidence rate (IR; event/100 patient-yrs of exposure; based on LTE data, 95% CI) for AE of interest were the following: serious AE 7.73 (6.96-8.58), infection 38.60 (36.24-41.12), serious infection 1.68 (1.35-2.07), malignancies 1.09 (0.84-1.42), and autoimmune disorders 1.33 (1.05-1.69), and were stable over time. No association between immunogenicity and either worsening of ABA safety or loss of efficacy was noted. Efficacy in the LTE was consistent with the DB period and was maintained to the end of the study. CONCLUSION: These 5-year data establish that SC ABA (125 mg/wk) has a consistent safety profile and durable efficacy for longterm treatment of patients with RA who had an inadequate response to MTX.


Assuntos
Abatacepte/uso terapêutico , Antirreumáticos/uso terapêutico , Artrite Reumatoide/tratamento farmacológico , Abatacepte/administração & dosagem , Abatacepte/efeitos adversos , Antirreumáticos/administração & dosagem , Antirreumáticos/efeitos adversos , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Humanos , Injeções Intravenosas , Injeções Subcutâneas , Masculino , Metotrexato/uso terapêutico , Pessoa de Meia-Idade , Resultado do Tratamento
20.
JCO Clin Cancer Inform ; 2: 1-14, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30652553

RESUMO

PURPOSE: Despite the intra- and intertumoral heterogeneity seen in glioblastoma multiforme (GBM), there is little definitive data on the underlying cause of the differences in patient survivals. Serial imaging assessment of tumor growth allows quantification of tumor growth kinetics (TGK) measured in terms of changes in the velocity of radial expansion seen on imaging. Because a systematic study of this entire TGK phenotype-growth before treatment and during each treatment to recurrence -has never been coordinately studied in GBMs, we sought to identify whether patients cluster into discrete groups on the basis of their TGK. PATIENTS AND METHODS: From our multi-institutional database, we identified 48 patients who underwent maximally safe resection followed by radiotherapy with imaging follow-up through the time of recurrence. The patients were then clustered into two groups through a k-means algorithm taking as input only the TGK before and during treatment. RESULTS: There was a significant survival difference between the clusters ( P = .003). Paradoxically, patients among the long-lived cluster had significantly larger tumors at diagnosis ( P = .027) and faster growth before treatment ( P = .003) but demonstrated a better response to adjuvant chemotherapy ( P = .048). A predictive model was built to identify which cluster patients would likely fall into on the basis of information that would be available to clinicians immediately after radiotherapy (accuracy, 90.3%). CONCLUSION: Dichotomizing the heterogeneity of GBMs into two populations-one faster growing yet more responsive with increased survival and one slower growing yet less responsive with shorter survival-suggests that many patients who receive standard-of-care treatments may get better benefit from select alternative treatments.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/terapia , Encéfalo/cirurgia , Glioblastoma/diagnóstico por imagem , Glioblastoma/terapia , Adulto , Idoso , Quimioterapia Adjuvante , Análise por Conglomerados , Feminino , Humanos , Cinética , Aprendizado de Máquina , Masculino , Pessoa de Meia-Idade , Fenótipo , Estudos Prospectivos , Radioterapia Adjuvante , Análise de Sobrevida , Resultado do Tratamento , Adulto Jovem
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