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OBJECTIVES: To investigate whether a history of traumatic brain injury (TBI) is associated with greater long-term grey-matter loss in patients with mild cognitive impairment (MCI). METHODS: 85 patients with MCI were identified, including 26 with a previous history of traumatic brain injury (MCI[TBI-]) and 59 without (MCI[TBI+]). Cortical thickness was evaluated by segmenting T1-weighted MRI scans acquired longitudinally over a 2-year period. Bayesian multilevel modelling was used to evaluate group differences in baseline cortical thickness and longitudinal change, as well as group differences in neuropsychological measures of executive function. RESULTS: At baseline, the MCI[TBI+] group had less grey matter within right entorhinal, left medial orbitofrontal and inferior temporal cortex areas bilaterally. Longitudinally, the MCI[TBI+] group also exhibited greater longitudinal declines in left rostral middle frontal, the left caudal middle frontal and left lateral orbitofrontal areas sover the span of 2 years (median = 1-2%, 90%HDI [-0.01%: -0.001%], probability of direction (PD) = 90-99%). The MCI[TBI+] group also displayed greater longitudinal declines in Trail-Making-Test (TMT)-derived ratio (median: 0.737%, 90%HDI: [0.229%: 1.31%], PD = 98.8%) and differences scores (median: 20.6%, 90%HDI: [-5.17%: 43.2%], PD = 91.7%). CONCLUSIONS: Our findings support the notion that patients with MCI and a history of TBI are at risk of accelerated neurodegeneration, displaying greatest evidence for cortical atrophy within the left middle frontal and lateral orbitofrontal frontal cortex. Importantly, these results suggest that long-term TBI-mediated atrophy is more pronounced in areas vulnerable to TBI-related mechanical injury, highlighting their potential relevance for diagnostic forms of intervention in TBI.
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Lesões Encefálicas Traumáticas , Disfunção Cognitiva , Substância Cinzenta , Imageamento por Ressonância Magnética , Humanos , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/patologia , Disfunção Cognitiva/diagnóstico por imagem , Masculino , Feminino , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/complicações , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Idoso , Pessoa de Meia-Idade , Estudos Longitudinais , Testes Neuropsicológicos , Córtex Cerebral/diagnóstico por imagem , Córtex Cerebral/patologia , Teorema de BayesRESUMO
Type 2 diabetes mellitus (T2DM) and hypertension are risk factors for cerebral small vessel disease (SVD); however, few studies have characterised their relationships with MRI-visible perivascular spaces (PVS). MRI was used to quantify deep (d) and periventricular (p) white matter hyperintensities (WMH), lacunes, PVS in the white matter (wmPVS) or basal ganglia (bgPVS), and diffusion metrics in white matter. Patients with T2DM had greater wmPVS volume and there were greater wmPVS volumes in patients with T2DM and hypertension together. Counterfactual moderated mediation models found indirect effects of T2DM on volumes of other SVD and diffusion markers that were mediated by wmPVS: pWMH, dWMH, periventricular lacunes, and deep lacunes, and progression of deep lacunes over 1 year, in patients with hypertension, but not in patients without hypertension. Studying the regulation of cortical perivascular fluid dynamics may reveal mechanisms that mediate the impact of T2DM on cerebral small vessels.
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BACKGROUND: Acute change in gait speed while performing a mental task [dual-task gait cost (DTC)], and hyperintensity magnetic resonance imaging signals in white matter are both important disability predictors in older individuals with history of stroke (poststroke). It is still unclear, however, whether DTC is associated with overall hyperintensity volume from specific major brain regions in poststroke. METHODS: This is a cohort study with a total of 123 older (69 ± 7 years of age) participants with history of stroke were included from the Ontario Neurodegenerative Disease Research Initiative. Participants were clinically assessed and had gait performance assessed under single- and dual-task conditions. Structural neuroimaging data were analyzed to measure both, white matter hyperintensity (WMH) and normal appearing volumes. Percentage of WMH volume in frontal, parietal, occipital, and temporal lobes as well as subcortical hyperintensities in basal ganglia + thalamus were the main outcomes. Multivariate models investigated associations between DTC and hyperintensity volumes, adjusted for age, sex, years of education, global cognition, vascular risk factors, APOE4 genotype, residual sensorimotor symptoms from previous stroke and brain volume. RESULTS: There was a significant positive global linear association between DTC and hyperintensity burden (adjusted Wilks' λ = .87, P = .01). Amongst all WMH volumes, hyperintensity burden from basal ganglia + thalamus provided the most significant contribution to the global association (adjusted ß = .008, η2 = .03; P = .04), independently of brain atrophy. CONCLUSIONS: In poststroke, increased DTC may be an indicator of larger white matter damages, specifically in subcortical regions, which can potentially affect the overall cognitive processing and decrease gait automaticity by increasing the cortical control over patients' locomotion.
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Doenças Neurodegenerativas , Acidente Vascular Cerebral , Substância Branca , Humanos , Idoso , Substância Branca/diagnóstico por imagem , Substância Branca/patologia , Estudos de Coortes , Doenças Neurodegenerativas/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Marcha , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia , Imageamento por Ressonância MagnéticaRESUMO
BACKGROUND AND PURPOSE: The pathophysiology of Parkinson's disease (PD) negatively affects brain network connectivity, and in the presence of brain white matter hyperintensities (WMHs) cognitive and motor impairments seem to be aggravated. However, the role of WMHs in predicting accelerating symptom worsening remains controversial. The objective was to investigate whether location and segmental brain WMH burden at baseline predict cognitive and motor declines in PD after 2 years. METHODS: Ninety-eight older adults followed longitudinally from Ontario Neurodegenerative Diseases Research Initiative with PD of 3-8 years in duration were included. Percentages of WMH volumes at baseline were calculated by location (deep and periventricular) and by brain region (frontal, temporal, parietal, occipital lobes and basal ganglia + thalamus). Cognitive and motor changes were assessed from baseline to 2-year follow-up. Specifically, global cognition, attention, executive function, memory, visuospatial abilities and language were assessed as were motor symptoms evaluated using the Movement Disorder Society Unified Parkinson's Disease Rating Scale Part III, spatial-temporal gait variables, Freezing of Gait Questionnaire and Activities Specific Balance Confidence Scale. RESULTS: Regression analysis adjusted for potential confounders showed that total and periventricular WMHs at baseline predicted decline in global cognition (p < 0.05). Also, total WMH burden predicted the decline of executive function (p < 0.05). Occipital WMH volumes also predicted decline in global cognition, visuomotor attention and visuospatial memory declines (p < 0.05). WMH volumes at baseline did not predict motor decline. CONCLUSION: White matter hyperintensity burden at baseline predicted cognitive but not motor decline in early to mid-stage PD. The motor decline observed after 2 years in these older adults with PD is probably related to the primary neurodegenerative process than comorbid white matter pathology.
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Disfunção Cognitiva , Transtornos Neurológicos da Marcha , Doenças Neurodegenerativas , Doença de Parkinson , Substância Branca , Humanos , Idoso , Substância Branca/patologia , Doenças Neurodegenerativas/patologia , Ontário , Imageamento por Ressonância Magnética/métodos , Cognição/fisiologia , Disfunção Cognitiva/patologiaRESUMO
Background Cerebral small vessel disease is associated with higher ratios of soluble-epoxide hydrolase derived linoleic acid diols (12,13-dihydroxyoctadecenoic acid [DiHOME] and 9,10-DiHOME) to their parent epoxides (12(13)-epoxyoctadecenoic acid [EpOME] and 9(10)-EpOME); however, the relationship has not yet been examined in stroke. Methods and Results Participants with mild to moderate small vessel stroke or large vessel stroke were selected based on clinical and imaging criteria. Metabolites were quantified by ultra-high-performance liquid chromatography-mass spectrometry. Volumes of stroke, lacunes, white matter hyperintensities, magnetic resonance imaging visible perivascular spaces, and free water diffusion were quantified from structural and diffusion magnetic resonance imaging (3 Tesla). Adjusted linear regression models were used for analysis. Compared with participants with large vessel stroke (n=30), participants with small vessel stroke (n=50) had a higher 12,13-DiHOME/12(13)-EpOME ratio (ß=0.251, P=0.023). The 12,13-DiHOME/12(13)-EpOME ratio was associated with more lacunes (ß=0.266, P=0.028) but not with large vessel stroke volumes. Ratios of 12,13-DiHOME/12(13)-EpOME and 9,10-DiHOME/9(10)-EpOME were associated with greater volumes of white matter hyperintensities (ß=0.364, P<0.001; ß=0.362, P<0.001) and white matter MRI-visible perivascular spaces (ß=0.302, P=0.011; ß=0.314, P=0.006). In small vessel stroke, the 12,13-DiHOME/12(13)-EpOME ratio was associated with higher white matter free water diffusion (ß=0.439, P=0.016), which was specific to the temporal lobe in exploratory regional analyses. The 9,10-DiHOME/9(10)-EpOME ratio was associated with temporal lobe atrophy (ß=-0.277, P=0.031). Conclusions Linoleic acid markers of cytochrome P450/soluble-epoxide hydrolase activity were associated with small versus large vessel stroke, with small vessel disease markers consistent with blood brain barrier and neurovascular-glial disruption, and temporal lobe atrophy. The findings may indicate a novel modifiable risk factor for small vessel disease and related neurodegeneration.
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Doenças de Pequenos Vasos Cerebrais , Acidente Vascular Cerebral , Humanos , Ácido Linoleico , Oxilipinas , Epóxido Hidrolases , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia , Doenças de Pequenos Vasos Cerebrais/diagnóstico por imagem , Imageamento por Ressonância Magnética , Atrofia , ÁguaRESUMO
Alterations in tissue microstructure in normal-appearing white matter (NAWM), specifically measured by diffusion tensor imaging (DTI) fractional anisotropy (FA), have been associated with cognitive outcomes following stroke. The purpose of this study was to comprehensively compare conventional DTI measures of tissue microstructure in NAWM to diverse vascular brain lesions in people with cerebrovascular disease (CVD) and to examine associations between FA in NAWM and cerebrovascular risk factors. DTI metrics including fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were measured in cerebral tissues and cerebrovascular anomalies from 152 people with CVD participating in the Ontario Neurodegenerative Disease Research Initiative (ONDRI). Ten cerebral tissue types were segmented including NAWM, and vascular lesions including stroke, periventricular and deep white matter hyperintensities, periventricular and deep lacunar infarcts, and perivascular spaces (PVS) using T1-weighted, proton density-weighted, T2-weighted, and fluid attenuated inversion recovery MRI scans. Mean DTI metrics were measured in each tissue region using a previously developed DTI processing pipeline and compared between tissues using multivariate analysis of covariance. Associations between FA in NAWM and several CVD risk factors were also examined. DTI metrics in vascular lesions differed significantly from healthy tissue. Specifically, all tissue types had significantly different MD values, while FA was also found to be different in most tissue types. FA in NAWM was inversely related to hypertension and modified Rankin scale (mRS). This study demonstrated the differences between conventional DTI metrics, FA, MD, AD, and RD, in cerebral vascular lesions and healthy tissue types. Therefore, incorporating DTI to characterize the integrity of the tissue microstructure could help to define the extent and severity of various brain vascular anomalies. The association between FA within NAWM and clinical evaluation of hypertension and disability provides further evidence that white matter microstructural integrity is impacted by cerebrovascular function.
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We propose a novel image analysis framework to automate analysis of X-ray microtomography images of sintering ceramics and glasses, using open-source toolkits and machine learning. Additive manufacturing (AM) of glasses and ceramics usually requires sintering of green bodies. Sintering causes shrinkage, which presents a challenge for controlling the metrology of the final architecture. Therefore, being able to monitor sintering in 3D over time (termed 4D) is important when developing new porous ceramics or glasses. Synchrotron X-ray tomographic imaging allows in situ, real-time capture of the sintering process at both micro and macro scales using a furnace rig, facilitating 4D quantitative analysis of the process. The proposed image analysis framework is capable of tracking and quantifying the densification of glass or ceramic particles within multiple volumes of interest (VOIs) along with structural changes over time using 4D image data. The framework is demonstrated by 4D quantitative analysis of bioactive glass ICIE16 within a 3D-printed scaffold. Here, densification of glass particles within 3 VOIs were tracked and quantified along with diameter change of struts and interstrut pore size over the 3D image series, delivering new insights on the sintering mechanism of ICIE16 bioactive glass particles in both micro and macro scales.
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PURPOSE: Magnetic resonance imaging (MRI) scanner-specific geometric distortions may contribute to scanner induced variability and decrease volumetric measurement precision for multi-site studies. The purpose of this study was to determine whether geometric distortion correction increases the precision of brain volumetric measurements in a multi-site multi-scanner study. METHODS: Geometric distortion variation was quantified over a one-year period at 10 sites using the distortion fields estimated from monthly 3D T1-weighted MRI geometrical phantom scans. The variability of volume and distance measurements were quantified using synthetic volumes and a standard quantitative MRI (qMRI) phantom. The effects of geometric distortion corrections on MRI derived volumetric measurements of the human brain were assessed in two subjects scanned on each of the 10 MRI scanners and in 150 subjects with cerebrovascaular disease (CVD) acquired across imaging sites. RESULTS: Geometric distortions were found to vary substantially between different MRI scanners but were relatively stable on each scanner over a one-year interval. Geometric distortions varied spatially, increasing in severity with distance from the magnet isocenter. In measurements made with the qMRI phantom, the geometric distortion correction decreased the standard deviation of volumetric assessments by 35% and distance measurements by 42%. The average coefficient of variance decreased by 16% in gray matter and white matter volume estimates in the two subjects scanned on the 10 MRI scanners. CONCLUSION: Geometric distortion correction using an up-to-date correction field is recommended to increase precision in volumetric measurements made from MRI images.
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Encéfalo , Imageamento por Ressonância Magnética , Encéfalo/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética/métodos , Imagens de FantasmasRESUMO
The measure of White Blood Cells (WBC) in the blood is an important indicator of pathological conditions. Computer vision based methods for differential counting of WBC are increasing due to their advantages over traditional methods. However, most of these methods are proposed for single WBC images which are pre-processed, and do not generalize for raw microscopic images with multiple WBC. Moreover, they do not have the capability to detect the absence of WBC in the images. This paper proposes an image processing algorithm based on K-Means clustering to detect the presence of WBC in raw microscopic images and to localize them, and a VGG-16 classifier to classify those cells with a classification accuracy of 95.89%.
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Processamento de Imagem Assistida por Computador , Leucócitos , Algoritmos , Análise por Conglomerados , Contagem de LeucócitosRESUMO
The processing of brain diffusion tensor imaging (DTI) data for large cohort studies requires fully automatic pipelines to perform quality control (QC) and artifact/outlier removal procedures on the raw DTI data prior to calculation of diffusion parameters. In this study, three automatic DTI processing pipelines, each complying with the general ENIGMA framework, were designed by uniquely combining multiple image processing software tools. Different QC procedures based on the RESTORE algorithm, the DTIPrep protocol, and a combination of both methods were compared using simulated ground truth and artifact containing DTI datasets modeling eddy current induced distortions, various levels of motion artifacts, and thermal noise. Variability was also examined in 20 DTI datasets acquired in subjects with vascular cognitive impairment (VCI) from the multi-site Ontario Neurodegenerative Disease Research Initiative (ONDRI). The mean fractional anisotropy (FA), mean diffusivity (MD), axial diffusivity (AD), and radial diffusivity (RD) were calculated in global brain grey matter (GM) and white matter (WM) regions. For the simulated DTI datasets, the measure used to evaluate the performance of the pipelines was the normalized difference between the mean DTI metrics measured in GM and WM regions and the corresponding ground truth DTI value. The performance of the proposed pipelines was very similar, particularly in FA measurements. However, the pipeline based on the RESTORE algorithm was the most accurate when analyzing the artifact containing DTI datasets. The pipeline that combined the DTIPrep protocol and the RESTORE algorithm produced the lowest standard deviation in FA measurements in normal appearing WM across subjects. We concluded that this pipeline was the most robust and is preferred for automated analysis of multisite brain DTI data.
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Disfunção Cognitiva/diagnóstico por imagem , Imagem de Tensor de Difusão/métodos , Imagem de Tensor de Difusão/normas , Processamento Eletrônico de Dados/métodos , Controle de Qualidade , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Anisotropia , Artefatos , Estudos de Coortes , Feminino , Substância Cinzenta/diagnóstico por imagem , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Ontário , Software , Substância Branca/diagnóstico por imagemRESUMO
INTRODUCTION: Trebananib, a peptide-Fc fusion protein, blocks angiogenesis by inhibiting binding of angiopoietin-1/2 to the receptor tyrosine kinase Tie2. Trebananib plus trastuzumab and paclitaxel was evaluated in human epidermal growth factor receptor 2-positive breast cancer in an open-label phase 1b clinical study. PATIENTS AND METHODS: Women with human epidermal growth factor receptor 2-positive breast cancer received weekly paclitaxel (80 mg/m2), trastuzumab (8 mg/m2 then 6 mg/kg every 3 weeks), and intravenous trebananib (10 mg/kg or 30 mg/kg weekly) beginning week 2. The primary end point was the incidence of dose-limiting toxicities. Secondary end points included incidence of adverse events (AEs), pharmacokinetics, and tumor response (objective response and duration of response). RESULTS: Forty women were enrolled; 2 experienced dose-limiting toxicities (grade 3 ocular transient ischemic attack [10 mg/kg cohort] and grade 3 elevation in γ-glutamyl transferase [30 mg/kg cohort]). The most common treatment-emergent AEs were peripheral edema (n = 28), diarrhea (n = 27), alopecia (n = 26), fatigue (n = 24), and nausea (n = 24). Maximum observed concentration and area under the concentration-time curve increased proportionally with the trebananib dose. Objective response was confirmed in 31 patients. In the 10 mg/kg cohort, 16 patients (80%) experienced partial response, and none experienced complete response. In the 30 mg/kg cohort, 12 patients (71%) experienced partial response and 3 (18%) experienced complete response. Median (95% confidence interval) duration of response in the 10 and 30 mg/kg cohorts was 12.6 (4.3-20.2) and 16.6 (8.2-not estimable) months, respectively. CONCLUSION: This phase 1b study showed that trebananib was tolerated with manageable AEs at a dose up to 30 mg/kg weekly. Trebananib demonstrated anticancer activity, as indicated by objective response and duration of response.
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Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Receptor ErbB-2/metabolismo , Adulto , Idoso , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Estudos de Coortes , Feminino , Seguimentos , Humanos , Dose Máxima Tolerável , Pessoa de Meia-Idade , Metástase Neoplásica , Recidiva Local de Neoplasia/metabolismo , Recidiva Local de Neoplasia/patologia , Paclitaxel/administração & dosagem , Prognóstico , Proteínas Recombinantes de Fusão/administração & dosagem , Trastuzumab/administração & dosagemRESUMO
BACKGROUND: Hypertension (HT) is identified as a highly prevalent cardiovascular risk factor and also as a separate disease entity, leading to significant mortality and morbidity. The rate of HT is increasing worldwide with a faster rate identified in developing countries. Thus, it is important to evaluate epidemiological patterns of chronic HT in a developing country like Sri Lanka. METHODOLOGY: This is a cross-sectional descriptive study conducted at the Teaching Hospital Peradeniya, Sri Lanka, to assess symptoms and risk factors among patients with chronic HT. RESULTS: In a cohort of 266 chronic hypertensives, the mean values for age of population, age of onset, and duration of HT, respectively, are 63, 45, and 8 years. At presentation, 24.8% were asymptomatic. The commonest presentation at diagnosis was dizziness accounting for 33.8% cases, followed by chest pain, headache, loss of consciousness, and shortness of breath accounting for 7.5%, 13.5%, 2.6%, and 4.5%, respectively. Approximately 36.5% of patients had a positive family history. Fathers of 7.1% patients, mothers of 19.2%, and both parents of 10.2% patients had HT. 38.7% of patients had one or more siblings with HT. 34.6% had diabetes mellitus. CONCLUSION: Symptoms of those with HT are mostly nonspecific and should be considered as possible warning signs prior to the development of sinister complications of the disease. Family history of HT with affected siblings, or one of the parents, was, observed in more than one-third of patients. Early screening and prevention of modifiable risk factors are important in these patients to prevent debilitating complications.
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Países em Desenvolvimento , Hipertensão/complicações , Hipertensão/epidemiologia , Doenças Assintomáticas/epidemiologia , Dor no Peito/epidemiologia , Dor no Peito/etiologia , Estudos de Coortes , Estudos Transversais , Diabetes Mellitus/epidemiologia , Tontura/epidemiologia , Tontura/etiologia , Dispneia/epidemiologia , Dispneia/etiologia , Pai/estatística & dados numéricos , Feminino , Cefaleia/epidemiologia , Cefaleia/etiologia , Humanos , Hipertensão/genética , Masculino , Pessoa de Meia-Idade , Mães/estatística & dados numéricos , Prevalência , Fatores de Risco , Irmãos , Sri Lanka/epidemiologia , Avaliação de Sintomas , Centros de Atenção Terciária , Inconsciência/epidemiologia , Inconsciência/etiologiaRESUMO
Diabetes mellitus is a major health problem which needs regular glucose monitoring for management of the disease. Invasive blood glucose measuring systems with acceptable accuracy are currently used for measurements. Several non- invasive blood glucose measurement techniques are reported in research literature, but most of them are not commercially available due to low accuracy or dependency on individual physiological parameters. This paper presents a hybrid technique to measure blood glucose level non-invasively using a combination of multi-wavelength Near Infrared (NIR) spectroscopy and bio-impedance spectroscopy. Physiological parameters of individuals and other environmental factors that affect non-invasive glucose measurements have been identified and compensated to make the device work on any person without calibrations. The measured parameters, along with the glucose level of the subject obtained from a commercial blood glucose meter is used to train a Random Forest regression algorithm. A training set of 315 data samples were used for the development of the system. The accuracy of predictions was tested using a testing set of 80 data samples. The trained system can predict the blood glucose levels non-invasively with 90.7% accuracy.
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Automonitorização da Glicemia/métodos , Glicemia/análise , Diabetes Mellitus , Algoritmos , Calibragem , Espectroscopia Dielétrica , Humanos , Espectroscopia de Luz Próxima ao InfravermelhoRESUMO
Loss of ejaculation can follow transurethral resection of the prostate (TURP). Periverumontanal prostate tissue is preserved in ejaculation-preserving TURP (ep-TURP). Knowledge of ejaculatory duct anatomy in relation to the prostatic urethra can help in ep-TURP. This was evaluated in cross-sections of the prostate using a 3 D model to determine a safe zone for resecting the prostate in ep-TURP. A 3 D reconstruction of the ejaculatory ducts was developed on the basis of six prostate gland cross-sections. The measurements obtained from the 3 D model were standardized according to the maximum width of the prostate. Simple linear regressions were used to predict the relationships of the ejaculatory ducts. The maximum widths of the prostates ranged from 22.60 to 52.10 mm. The ejaculatory ducts entered the prostate with a concavity directed posterolaterally. They then proceeded toward the seminal colliculus in a fairly straight course, and from that point they angulated anteromedially. As they opened into the prostatic urethra they diverged. Significant regression models predicted the relationships of the ejaculatory ducts to the prostatic urethra based on the sizes of the prostates. The 3 D anatomy of ejaculatory ducts can be predicted on the basis of prostate width. The ejaculatory ducts can be preserved with 95% accuracy if a block of tissue 7.5 mm from the midline on either side of the seminal colliculus is preserved, up to 10 mm proximal to the level of the seminal colliculus, during TURP. Clin. Anat. 31:456-461, 2018. © 2017 Wiley Periodicals, Inc.
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Ductos Ejaculatórios/anatomia & histologia , Próstata/anatomia & histologia , Uretra/anatomia & histologia , Variação Anatômica , Estudos Transversais , Humanos , Masculino , Pessoa de Meia-Idade , Análise de RegressãoRESUMO
OBJECTIVE: Treatment options for patients with recurrent ovarian carcinoma are diverse, and different therapies are recommended based on platinum-free interval (PFI). Data examining the association between platinum sensitivity, treatment strategy, and outcomes are limited, particularly for partially platinum-sensitive (PPS) patients. This study characterized clinical features and outcomes in patients with recurrent ovarian carcinoma in the context of sensitivity to platinum-based therapy. METHODS: Anonymized case records were obtained from eligible European medical sites. Eligible patients were 18 years or older with epithelial ovarian carcinoma who had received 1 or more platinum-based therapies and had 1 or more subsequent relapses. Patient records were categorized by PFI and analyzed based on demographic and clinical data using descriptive statistics. RESULTS: There was no difference between PFI in PPS patients receiving platinum versus nonplatinum therapy (8.9 [range, 6.0-12.0] and 8.3 [range, 6.0-11.3] months, respectively). Overall survival in patients with platinum-sensitive, PPS, platinum-resistant, and platinum-refractory disease was 43.0 (95% confidence interval [95% CI], 25.1-42.3), 20.5 (95% CI, 17.7-24.8), 12.7 (95% CI, 10.4-14.2), and 9.8 (95% CI, 6.6-14.9) months, respectively. Among PPS patients, overall survival was 23.5 (95% CI, 18.4-37.3) and 18.7 (95% CI, 11.0-23.5) months for those who received platinum and nonplatinum-based therapy, respectively. No demographic or clinical characteristics were identified that indicated a difference between PPS patients who received platinum-based therapy versus those who did not. CONCLUSIONS: Partially platinum-sensitive patients with recurrent ovarian carcinoma who received platinum-based therapy had improved outcomes compared with those who did not. No clear demographic criteria for choosing platinum- versus nonplatinum-based therapy for PPS patients were identified from patient records.
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Antineoplásicos/uso terapêutico , Carcinoma/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Recidiva Local de Neoplasia/tratamento farmacológico , Compostos Organoplatínicos/uso terapêutico , Neoplasias Ovarianas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Hospitalização/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Adulto JovemRESUMO
OBJECTIVE: To examine the tolerability and antitumor activity of trebananib plus pegylated liposomal doxorubicin (PLD) or topotecan in recurrent platinum-resistant or partially platinum-sensitive ovarian cancer. METHODS: In this open-label phase 1b study, patients received trebananib 10 mg/kg or 15 mg/kg IV QW plus PLD 50 mg/m(2) (cohorts A1 and A3, respectively) or topotecan 4 mg/m(2) (cohorts B1 and B3, respectively). Endpoints were dose-limiting toxicity (DLT; primary); treatment-emergent adverse events (AEs), overall response rate, anti-trebananib antibodies, and pharmacokinetics (secondary). RESULTS: 103 patients were enrolled. One patient in A1 and B1 had DLTs. Across all cohorts, the most common AEs were nausea, fatigue, and peripheral edema. Across both trebananib plus PLD cohorts (A1/A3), grade 4 AEs were pulmonary embolism, disease progression, and anemia. Two patients had grade 5 intestinal perforation (n=1) and sudden death (n=1). Across both trebananib plus topotecan cohorts (B1/B3), grade 4 AEs were neutropenia, hypokalemia, decreased granulocyte count, chest pain, dyspnea, decreased neutrophil count, and pulmonary embolism. Two patients had grade 5 disease progression. One patient had grade 5 pleural effusion associated with progressive disease. Confirmed objective response rates were 36.0% (A1), 34.8% (A3), 16.7% (B1), and 0.0% (B3). Median progression-free survival duration (months) was 7.4 (A1), 7.1 (A3), 3.5 (B1), and 3.1 (B3), respectively. No drug-drug interactions were apparent. CONCLUSIONS: Trebananib 10mg/kg and 15 mg/kg IV QW plus PLD or topotecan appear to have acceptable toxicity profiles in recurrent platinum-resistant or partially platinum-sensitive ovarian cancer. Antitumor activity was evident across all cohorts.
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Inibidores da Angiogênese/administração & dosagem , Antibióticos Antineoplásicos/administração & dosagem , Doxorrubicina/análogos & derivados , Recidiva Local de Neoplasia/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Compostos de Platina/uso terapêutico , Proteínas Recombinantes de Fusão/administração & dosagem , Inibidores da Topoisomerase I/administração & dosagem , Topotecan/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/efeitos adversos , Antibióticos Antineoplásicos/efeitos adversos , Doxorrubicina/administração & dosagem , Doxorrubicina/efeitos adversos , Resistencia a Medicamentos Antineoplásicos , Quimioterapia Combinada , Feminino , Humanos , Pessoa de Meia-Idade , Compostos de Platina/efeitos adversos , Polietilenoglicóis/administração & dosagem , Polietilenoglicóis/efeitos adversos , Proteínas Recombinantes de Fusão/efeitos adversos , Inibidores da Topoisomerase I/efeitos adversos , Topotecan/efeitos adversosRESUMO
Atherosclerosis at the carotid bifurcation can result in cerebral emboli, which in turn can block the blood supply to the brain causing ischemic strokes. Noninvasive imaging tools that better characterize arterial wall, and atherosclerotic plaque structure and composition may help to determine the factors which lead to the development of unstable lesions, and identify patients at risk of plaque disruption and stroke. Carotid magnetic resonance (MR) imaging allows for the characterization of carotid vessel wall and plaque composition, the characterization of normal and pathological arterial wall, the quantification of plaque size, and the detection of plaque integrity. On the other hand, various ultrasound (US) measurements have also been used to quantify atherosclerosis, carotid stenosis, intima-media thickness, total plaque volume, total plaque area, and vessel wall volume. Combining the complementary information provided by 3D MR and US carotid images may lead to a better understanding of the underlying compositional and textural factors that define plaque and wall vulnerability, which may lead to better and more effective stroke prevention strategies and patient management. Combining these images requires nonrigid registration to correct the nonlinear misalignments caused by relative twisting and bending in the neck due to different head positions during the two image acquisition sessions. The high degree of freedom and large number of parameters associated with existing nonrigid image registration methods causes several problems including unnatural plaque morphology alteration, high computational complexity, and low reliability. Thus, a "twisting and bending" model was used with only six parameters to model the normal movement of the neck for nonrigid registration. The registration technique was evaluated using 3D US and MR carotid images at two field strengths, 1.5 and 3.0 T, of the same subject acquired on the same day. The mean registration error between the segmented carotid artery wall boundaries in the target US image and the registered MR images was calculated using a distance-based error metric after applying a "twisting and bending" model based nonrigid registration algorithm. An average registration error of 1.4 +/- 0.3 mm was obtained for 1.5 T MR and 1.5 +/- 0.4 mm for 3.0 T MR, when registered with 3D US images using the nonrigid registration technique presented in this paper. Visual inspection of segmented vessel surfaces also showed a substantial improvement of alignment with this nonrigid registration technique compared to rigid registration.
Assuntos
Artérias Carótidas/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Algoritmos , Humanos , Sensibilidade e Especificidade , UltrassonografiaRESUMO
Atherosclerosis at the carotid bifurcation resulting in cerebral emboli is a major cause of ischemic stroke. Most strokes associated with carotid atherosclerosis can be prevented by lifestyle/dietary changes and pharmacological treatments if identified early by monitoring carotid plaque changes. Registration of 3-D ultrasound (US) images of carotid plaque obtained at different time points is essential for sensitive monitoring of plaque changes in volume and surface morphology. This registration technique should be nonrigid, since different head positions during image acquisition sessions cause relative bending and torsion in the neck, producing nonlinear deformations between the images. We modeled the movement of the neck using a "twisting and bending" model with only six parameters for nonrigid registration. We evaluated the algorithm using 3-D US carotid images acquired at two different head positions to simulate images acquired at different times. We calculated the mean registration error (MRE) between the segmented vessel surfaces in the target image and the registered image using a distance-based error metric after applying our "twisting and bending" model-based nonrigid registration algorithm. We achieved an average registration error of 0.80 +/-0.26 mm using our nonrigid registration technique, which was a significant improvement in registration accuracy over rigid registration, even with reduced degrees-of-freedom compared to the other nonrigid registration algorithms.
Assuntos
Inteligência Artificial , Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/diagnóstico por imagem , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Reconhecimento Automatizado de Padrão/métodos , Técnica de Subtração , Algoritmos , Simulação por Computador , Humanos , Aumento da Imagem/métodos , Modelos Cardiovasculares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , UltrassonografiaRESUMO
BACKGROUND: The production of oxidative stress as a result of postprandial hyperglycaemia is now recognized as an important contributing factor in the development of diabetes complications. The objective of this study was to examine the effects of pramlintide on plasma concentrations of glucose and several markers of oxidative stress in patients with type 2 diabetes following a standardized meal. METHODS: This was a randomized, single-blind, placebo-controlled, crossover study conducted at two clinical research centres in the United States. A total of 19 subjects (9 men and 10 women) with type 2 diabetes using mealtime insulin participated in the study. Pramlintide (120 microg), or placebo, and rapid-acting mealtime insulin were administered prior to a standardized meal on two separate study days. Plasma concentrations of glucose, nitrotyrosine (NT), oxidized-LDL cholesterol (OxLDL-C), and total radical trapping parameter (TRAP) were assessed during the 4-h postprandial period. RESULTS: Compared to placebo, pramlintide treatment reduced postprandial excursions of glucose, NT, and OxLDL-C and protected TRAP from consumption. Correlation analysis revealed positive associations between placebo-corrected glucose incremental AUC(0-4 h) and both NT and OxLDL-C and a negative association between placebo-corrected glucose incremental AUC(0-4h) and TRAP. CONCLUSIONS: The reduction in postprandial glucose excursions achieved with addition of pramlintide to rapid-acting insulin in type 2 diabetes was associated with a reduction in postprandial markers of oxidative stress.
Assuntos
Amiloide/uso terapêutico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Estresse Oxidativo/efeitos dos fármacos , Período Pós-Prandial/fisiologia , Adolescente , Adulto , Amiloide/efeitos adversos , Biomarcadores/sangue , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , LDL-Colesterol/sangue , Diabetes Mellitus Tipo 2/fisiopatologia , Feminino , Humanos , Insulina/análogos & derivados , Insulina/uso terapêutico , Insulina Lispro , Polipeptídeo Amiloide das Ilhotas Pancreáticas , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Tirosina/análogos & derivados , Tirosina/sangueRESUMO
Estimation of prostate location and volume is essential in determining a dose plan for ultrasound-guided brachytherapy, a common prostate cancer treatment. However, manual segmentation is difficult, time consuming and prone to variability. In this paper, we present a semi-automatic discrete dynamic contour (DDC) model based image segmentation algorithm, which effectively combines a multi-resolution model refinement procedure together with the domain knowledge of the image class. The segmentation begins on a low-resolution image by defining a closed DDC model by the user. This contour model is then deformed progressively towards higher resolution images. We use a combination of a domain knowledge based fuzzy inference system (FIS) and a set of adaptive region based operators to enhance the edges of interest and to govern the model refinement using a DDC model. The automatic vertex relocation process, embedded into the algorithm, relocates deviated contour points back onto the actual prostate boundary, eliminating the need of user interaction after initialization. The accuracy of the prostate boundary produced by the proposed algorithm was evaluated by comparing it with a manually outlined contour by an expert observer. We used this algorithm to segment the prostate boundary in 114 2D transrectal ultrasound (TRUS) images of six patients scheduled for brachytherapy. The mean distance between the contours produced by the proposed algorithm and the manual outlines was 2.70 +/- 0.51 pixels (0.54 +/- 0.10 mm). We also showed that the algorithm is insensitive to variations of the initial model and parameter values, thus increasing the accuracy and reproducibility of the resulting boundaries in the presence of noise and artefacts.