Multiparametrické zobrazení pomocí 3T magnetické rezonance dovoluje lépe pochopit mechanismy změny struktury, mikrostruktury látkové výměny i perfuze tkání v souvislosti s vývojem nádorového onemocnění. Kombinací morfologického zobrazení s analýzou farmakokinetiky difuzně váženým zobrazením a spektroskopií lze blíže specifikovat tkáně a přispět tak k diferenciální diagnóze nádorů, odhadnutí jejich biologického chování i předpovědi odpovědi na terapii, případně odpovědi posoudit.
Multi-parametric imaging using 3T magnetic resonance enables to improve knowledges about mechanisms of the structural, microstructural, metabolic and perfusion changes under conditions of oncogenesis. Such as combination of morphological imaging with an analysis of pharmacokinetics, diffusion weighted imaging and spectrosco-py allows to specify tissues in detail and to support to differential diagnosis of tumours, to estimate their behaviour, and to estimate the prognosis of therapy response or to assess it.
BACKGROUND: Perioperative goal directed therapy (pGDT) using flow monitoring has been associated with improved outcomes. However, its protocols are often based on stroke volume only: as a target for fluid loading, inotropic support and vasopressors (via mathematical coupling of systemic vascular resistance). In this trial, we have tested the multi-parametric pGDT protocol based on esophageal Doppler variables (corrected flow time, peak velocity) in intermediate-to-high risk patients undergoing gastrointestinal surgery. METHODS: Intermediate-to-high risk patients undergoing gastrointestinal surgery were randomized to standard care (control) or multi-parametric pGDT (intervention). Postoperative complications and death rate as well as hospital length of stay were assessed as primary and secondary outcomes. RESULTS: Overall, 140 patients (intervention, N.=71, and control, N.=69) were included and randomized out of 197 eligible. Higher vasoactive/inotropic drug use and lower fluid balance were observed in the intervention group leading to favorable hemodynamic profile. The pGDT intervention was associated with improved primary outcome (28 days mortality and morbidity defined as occurrence of any defined complication) - 20 patients (28.2%) versus 32 (46.4%) in the control group (P=0.036); RR 0.61 (95% CI: 0.39-0.95), P=0.03. No differences in mortality and hospital length of stay were observed between groups. CONCLUSIONS: In this monocentric trial the multi-parametric pGDT protocol based on domain specific functional hemodynamic parameters was associated with lower rate of postoperative complications in intermediate-to-high risk patients undergoing scheduled gastrointestinal procedures.
- MeSH
- Digestive System Surgical Procedures methods MeSH
- Early Goal-Directed Therapy MeSH
- Hemodynamics * MeSH
- Risk Assessment MeSH
- Middle Aged MeSH
- Humans MeSH
- Postoperative Complications prevention & control MeSH
- Prospective Studies MeSH
- Aged MeSH
- Treatment Outcome MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Randomized Controlled Trial MeSH
Statistics for Biology and Health -- Philip Hougaard -- Analysis of Multivariate Survival Data -- Survival Four different approaches to the analysis of such data are presented. /non-parametric models . 40 -- 2.1.4 Multiple events . 42 -- 2.2 Parametric methods . 43 -- 2.2.1 The models . 65 -- 2.3 Simple non-parametric methods 69 -- 2.3.1 The Kaplan-Meier estimate . 70 -- 2.3.2 models 184 -- 6.3.3 Non-parametric models for the disability model . 185 -- 6.3.4 Non-parametric models
Statistics for biology and health
1st ed. xvii, 542 s.
- Conspectus
- Statistika
- NML Fields
- statistika, zdravotnická statistika
- management, organizace a řízení zdravotnictví
BACKGROUND: High-intensity focused ultrasound (HIFU) emerged as a novel approach for the treatment of localized prostate cancer (PCa). However, prospective studies on HIFU-related outcomes and predictors of treatment failure (TF) remain scarce. MATERIALS AND METHODS: We conducted a multinational prospective cohort study among patients undergoing HIFU therapy for localized, low- to intermediate-risk PCa. Follow-up data on serial prostate specific antigen (PSA), multi-parametric magnetic resonance imaging (mpMRI), targeted/systematic biopsies, adverse events and functional outcomes were collected. The primary endpoint was TF, defined as histologically confirmed PCa requiring whole-gland salvage treatment. Uni- and multi-variable adjusted hazard ratios (HRs) were calculated using Cox proportional hazard regression models. RESULTS: At baseline, mean (standard deviation) age was 64.14 (7.19) years, with the majority of patients showing T-stage 1 (73.9%) and International Society of Urological Pathology grading system Grade 2 (58.8%). PSA nadir (median, 1.70 ng/mL) was reached after 6 months. Of all patients recruited, 16% had clinically significant PCa, as confirmed by biopsy, of which 13.4% had TF. Notably, T-stage and number of positive cores at initial biopsy were independent predictors of TF during follow-up (HR [95% CI] 1.27 [1.02-1.59] and 5.02 [1.80-14.03], respectively). Adverse events were minimal (17% and 8% early and late adverse events, respectively), with stable or improved functional outcomes in the majority of patients. CONCLUSIONS: This interim analysis of a multinational study on HIFU therapy for the management of low-to-intermediate-risk PCa reveals good functional outcomes, minimal adverse events and low incidence of TF over the short-term. Data on long-term outcomes, specifically as it relates to oncological outcomes, are awaited eagerly.
- MeSH
- High-Intensity Focused Ultrasound Ablation methods MeSH
- Cohort Studies MeSH
- Middle Aged MeSH
- Humans MeSH
- Multiparametric Magnetic Resonance Imaging MeSH
- Prostatic Neoplasms * therapy pathology MeSH
- Treatment Failure MeSH
- Proportional Hazards Models MeSH
- Prospective Studies MeSH
- Prostate-Specific Antigen * metabolism blood MeSH
- Aged MeSH
- Neoplasm Grading MeSH
- Ultrasound, High-Intensity Focused, Transrectal MeSH
- Salvage Therapy methods MeSH
- Check Tag
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Publication type
- Journal Article MeSH
- Multicenter Study MeSH
OBJECTIVE: Nowadays proper detection of cognitive impairment has become a challenge for the scientific community. Alzheimer's Disease (AD), the most common cause of dementia, has a high prevalence that is increasing at a fast pace towards epidemic level. In the not-so-distant future this fact could have a dramatic social and economic impact. In this scenario, an early and accurate diagnosis of AD could help to decrease its effects on patients, relatives and society. Over the last decades there have been useful advances not only in classic assessment techniques, but also in novel non-invasive screening methodologies. METHODS: Among these methods, automatic analysis of speech -one of the first damaged skills in AD patients- is a natural and useful low cost tool for diagnosis. RESULTS: In this paper a non-linear multi-task approach based on automatic speech analysis is presented. Three tasks with different language complexity levels are analyzed, and promising results that encourage a deeper assessment are obtained. Automatic classification was carried out by using classic Multilayer Perceptron (MLP) and Deep Learning by means of Convolutional Neural Networks (CNN) (biologically- inspired variants of MLPs) over the tasks with classic linear features, perceptual features, Castiglioni fractal dimension and Multiscale Permutation Entropy. CONCLUSION: Finally, the most relevant features are selected by means of the non-parametric Mann- Whitney U-test.
- MeSH
- Alzheimer Disease diagnosis MeSH
- Early Diagnosis MeSH
- Deep Learning MeSH
- Diagnosis, Computer-Assisted * methods MeSH
- Adult MeSH
- Cognitive Dysfunction diagnosis MeSH
- Cohort Studies MeSH
- Middle Aged MeSH
- Humans MeSH
- Speech Production Measurement MeSH
- Nonlinear Dynamics MeSH
- Neuropsychological Tests MeSH
- Speech * MeSH
- Pattern Recognition, Automated * methods MeSH
- Aged MeSH
- Speech Recognition Software MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Words like yeah, okay and (al)right are fairly unspecific in their lexical semantics, and not least for this reason there is a general tendency for them to occur with highly varied and expressive prosodic patterns across languages. Here we examine in depth the prosodic forms that express eight pragmatic functions of the Czech discourse marker jasně, including resignation, reassurance, surprise, indifference or impatience. Using a collection of 172 tokens from a corpus of scripted dialogues by 30 native speakers, we performed acoustic analyses, applied classification algorithms and solicited judgments from native listeners in a perceptual experiment. There appeared to be multi-parametric differences between jasně realizations in terms of their F0, timing and intensity patterns, which gave rise to generally consistent form-function mappings. For example, resignation seems to be realized with a falling intonation contour, relatively slow tempo, long wordinitial consonant and a short word-final vowel. Although the most significant prosodic parameters used for clustering analysis involved segment durations, all pragmatic functions were expressed by patterns of multiple features.
- MeSH
- Speech Acoustics * MeSH
- Phonation physiology MeSH
- Language * MeSH
- Communication MeSH
- Humans MeSH
- Speech Perception physiology MeSH
- Semantics * MeSH
- Verbal Behavior physiology MeSH
- Check Tag
- Humans MeSH
- Male MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Geographicals
- Czech Republic MeSH
This study is concerned with parametric radiation from an arbitrary axisymmetric planar source with a special focus on low-frequency difference-frequency fields. As a model equation accounting for nonlinearity, diffraction, and dissipation, the Westervelt equation is used. The difference-frequency-field patterns are calculated in the quasi-linear approximation by the method of successive approximations. A multi-layer integral for calculation of the acoustic field is reduced to a three-dimensional one by employing an approximate analytical description of the primary field with the use of a multi-Gaussian beam expansion. This integral is subsequently reduced in the paraxial approximation to a one-dimensional form which has previously been published in literature and which represents a means for fast calculations of secondary acoustic fields. The three-dimensional integral is calculated numerically and the numerical results predict nonzero amplitude of the low-frequency field in the vicinity of the source which is an effect that cannot be correctly encompassed in the paraxial approximation.
- MeSH
- Acoustics instrumentation MeSH
- Algorithms MeSH
- Time Factors MeSH
- Equipment Design MeSH
- Nonlinear Dynamics MeSH
- Numerical Analysis, Computer-Assisted MeSH
- Computer Simulation MeSH
- Motion MeSH
- Models, Theoretical * MeSH
- Pressure MeSH
- Vibration MeSH
- Sound * MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
Nádor prostaty, jako jeden z mála zhoubných nádorů, je obvyklými zobrazovacím metodami velmi špatně znázornitelný. Při sonografii, která je v diagnostice karcinomu prostaty standardně používána, je typické hypoechogenní ložisko patrné jen v 30 %, z čehož vyplývá nízká senzitivita TRUS. Jako slibná se v posledních letech jeví magnetická rezonance, zejména její multiparametrická analýza. Ložisko vyznačené magnetickou rezonancí je bioptováno buďto v reálném čase in-bore technikou či je použito některé z fúzních technik.
Prostate carcinoma is one of few malignant tumors being difficult to be diagnosed by conventional imaging methods. On ultrasonographythat is normally used in the diagnosis of prostate cancer, typical hypoechogenic lesion is visible in only 30 %, whichresults in low TRUS sensitivity. In recent years,MRI and especially multi-parametric analysis appears to be promising solution. MRIvisualised lesion is biopted either in real-time using in-bore technique or by selected fusion technique.
- Keywords
- cílená biopsie prostaty,
- MeSH
- Biopsy methods MeSH
- Diagnosis, Computer-Assisted MeSH
- Humans MeSH
- Magnetic Resonance Imaging * MeSH
- Prostatic Neoplasms * diagnostic imaging MeSH
- Image Processing, Computer-Assisted MeSH
- Prostate diagnostic imaging MeSH
- Image-Guided Biopsy * methods MeSH
- Check Tag
- Humans MeSH
- Publication type
- Review MeSH
Renal amyloid involvement results, especially, from AL (primary) or AA (secondary) amyloidosis. The extent of amyloid tissue deposits in the kidneys and the clinical course of amyloidosis not only depend on the type of basic process but also reflect the time of diagnosis and the ability to affect the underlying disease. We analyzed laboratory and clinical data from patients with bioptically proven renal amyloidosis. Renal amyloidosis was found in 99 patients (4.65%) from an overall number of 2,128 renal biopsies (RB) performed in our department during a period of 11 years (from 1995 to 2006). AA amyloidosis was diagnosed in 46 patients. Nephrotic syndrome was diagnosed in 27 patients (59%) with AA amyloidosis; all these patients had different degrees of proteinuria. Impaired renal function was discovered in 24 patients (52%); in three of these patients (6.5%) we had to start renal replacement therapy. Patients were treated with corticosteroids, disease-modifying antirheumatic drugs (DMARDs), and biological therapy in various regimens. Nine patients (19.5%) died during the one-year follow-up period; complications such as sepsis and cardiac failure were the leading causes of death. Median survival in the AA group was 54 months. Although for approximately half of patients different treatment regimens can lead to a partial remission or disease stabilization, the prognosis of patients with amyloidosis could be regarded as unsatisfactory.
- MeSH
- Amyloid metabolism MeSH
- Amyloidosis diagnosis epidemiology MeSH
- Survival Analysis MeSH
- Antirheumatic Agents therapeutic use MeSH
- Kidney Failure, Chronic diagnosis epidemiology MeSH
- Adult MeSH
- Risk Assessment MeSH
- Immunohistochemistry MeSH
- Incidence MeSH
- Biopsy, Needle MeSH
- Cohort Studies MeSH
- Drug Therapy, Combination MeSH
- Middle Aged MeSH
- Humans MeSH
- Nephrology statistics & numerical data MeSH
- Nephrotic Syndrome diagnosis epidemiology MeSH
- Kidney Diseases diagnosis drug therapy epidemiology MeSH
- Statistics, Nonparametric MeSH
- Prednisolone therapeutic use MeSH
- Prognosis MeSH
- Retrospective Studies MeSH
- Sex Distribution MeSH
- Aged MeSH
- Severity of Illness Index MeSH
- Age Distribution MeSH
- Kidney Function Tests MeSH
- Health Surveys MeSH
- Check Tag
- Adult MeSH
- Middle Aged MeSH
- Humans MeSH
- Male MeSH
- Aged MeSH
- Female MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Geographicals
- Czech Republic MeSH
OBJECTIVE: An extension of single- and multi-channel blind deconvolution is presented to improve the estimation of the arterial input function (AIF) in quantitative dynamic contrast enhanced magnetic resonance imaging (DCE-MRI). METHODS: The Lucy-Richardson expectation-maximization algorithm is used to obtain estimates of the AIF and the tissue residue function (TRF). In the first part of the algorithm, nonparametric estimates of the AIF and TRF are obtained. In the second part, the decaying part of the AIF is approximated by three decaying exponential functions with the same delay, giving an almost noise free semi-parametric AIF. Simultaneously, the TRF is approximated using the adiabatic approximation of the Johnson-Wilson (aaJW) pharmacokinetic model. RESULTS: In simulations and tests on real data, use of this AIF gave perfusion values close to those obtained with the corresponding previously published nonparametric AIF, and are more noise robust. CONCLUSION: When used subsequently in voxelwise perfusion analysis, these semi-parametric AIFs should give more correct perfusion analysis maps less affected by recording noise than the corresponding nonparametric AIFs, and AIFs obtained from arteries. SIGNIFICANCE: This paper presents a method to increase the noise robustness in the estimation of the perfusion parameter values in DCE-MRI.
- MeSH
- Algorithms MeSH
- Arteries pathology MeSH
- Contrast Media chemistry pharmacokinetics MeSH
- Magnetic Resonance Imaging * MeSH
- Mice, Inbred C57BL MeSH
- Mice MeSH
- Perfusion MeSH
- Computer Simulation MeSH
- Image Processing, Computer-Assisted * MeSH
- Reproducibility of Results MeSH
- Image Enhancement * MeSH
- Animals MeSH
- Check Tag
- Mice MeSH
- Female MeSH
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH