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1.
Sci Rep ; 12(1): 16894, 2022 10 07.
Article in English | MEDLINE | ID: mdl-36207367

ABSTRACT

Effective conservation actions to counteract the current decline of populations and species require a deep knowledge on their genetic structure. We used Single Nucleotide Polymorphisms (SNPs) to infer the population structure of the highly threatened freshwater pearl mussel Margaritifera margaritifera in the Iberian Peninsula. A total of 130 individuals were collected from 26 locations belonging to 16 basins. We obtained 31,692 SNPs through Genotyping by Sequencing (GBS) and used this dataset to infer population structure. Genetic diversity given as observed heterozygosity was low. Pairwise FST comparisons revealed low levels of genetic differentiation among geographically close populations. Up to 3 major genetic lineages were determined: Atlantic, Cantabrian and Douro. This structure suggests a close co-evolutionary process with brown trout (Salmo trutta), the primordial fish host of this mussel in the studied area. Some sub-basins showed some genetic structuring, whereas in others no intrapopulation differentiation was found. Our results confirm that genetic conservation units do not match individual basins, and that knowledge about the genetic structure is necessary before planning recovery plans that may involve relocation or restocking. The same reasoning should be applied to strictly freshwater species that are sessile or have restricted dispersal abilities and are currently imperiled worldwide.


Subject(s)
Bivalvia , Animals , Bivalvia/genetics , Fresh Water , Genetic Variation , Genomics , Seafood , Trout/genetics
2.
J Inorg Biochem ; 199: 110754, 2019 10.
Article in English | MEDLINE | ID: mdl-31401348

ABSTRACT

A series of PdII complexes with bis-(2-pyridylmethyl)glycine as a ligand of formula [PdX(bis-(2-pyridylmethyl)glycine)] where X = Cl, Br, I were prepared and the effect of the halogen nature in the antitumor activity of eight tumorigenic and one non-tumorigenic cell line was evaluated. The chloride derivative was further functionalized with a transferrin receptor binding peptide, generating the first PdII based metallopeptide. Its antitumor activity was also evaluated. However, among all the complexes, the chloride and iodine parent compounds showed the lowest GI50 values in the panel evaluated, and lowest GI50 than cisplatin in several cell lines. In contrast, the bromine derivative showed higher values of GI50 than chloride and iodine (around 30 - 50 µM). The same trend was observed for the bovine serum albumin binding constant with higher values for iodine, chlorine, and bromine in this order. In aqueous solution, the chloride is exchanged by water while the bromine and iodine are not. DNA was evaluated as a target and showed no significative interaction for all the compounds. The results suggest sulfur-rich proteins and not DNA as a target. This report represents the first PdII metallopeptide reported, its evaluation in solution and antitumor activity. This work opens the possibilities for further functionalization of PdII complexes and the importance of the halogen coordination in the design of novel metallodrugs.


Subject(s)
Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Halogens/chemistry , Palladium/chemistry , Peptides/chemistry , Peptides/pharmacology , Transferrin-Binding Proteins/chemistry , Antineoplastic Agents/chemical synthesis , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Coordination Complexes/chemical synthesis , HT29 Cells , Humans , MCF-7 Cells , Magnetic Resonance Spectroscopy , Peptides/chemical synthesis , Structure-Activity Relationship , X-Ray Diffraction
3.
Annu Int Conf IEEE Eng Med Biol Soc ; 2019: 6145-6148, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31947246

ABSTRACT

This paper is concerned with the automatic evaluation of selected tasks performed by people with intellectual Disabilities. According to the International Classification of Functioning, Disability and Health (ICF) system, subjects must be divided into two groups: group with no difficulty (N) and group with difficulty (D) being this classification based on performances obtained in a conventional table (CT) soccer. Three tasks, with different levels of difficulty, were proposed for performance evaluation. Experimental results were obtained on the basis of the task execution in both a CT and a robotics table (RT) soccer. All participants were able to perform tasks with the joystick on the RT soccer and the automatic evaluation system identified differences in reaction times with and without red color flag in the participants, on RT soccer. One of the tasks was completely performed by all the participants by using the RT soccer.


Subject(s)
Disabled Persons , Intellectual Disability , Robotics , Soccer , Humans
5.
Hum Mov Sci ; 54: 220-229, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28527424

ABSTRACT

The aim of the current study was to investigate the influence of chronic stretching on muscle performance (MP) by a systematic review. The search strategy included MEDLINE, PEDro, Cochrane CENTRAL, LILACS, and manual search from inception to June 2016. Randomized and controlled clinical trials, non-randomized, and single group studies that have analyzed the influence of flexibility training (FT) (using any stretching technique) on MP were included. Differently, studies with special populations (children, elderly, and people with any dysfunction/disease), and articles that have used FT protocols shorter than three weeks or 12 sessions were excluded. The MP assessment could have been performed by functional tests (e.g. jump, sprint, stretch-shortening cycle tasks), isometric contractions, and/or isotonic contractions. Twenty-eight studies were included out of 513. Seven studies evaluated MP by stretch-shortening cycle tasks, Ten studies evaluated MP by isometric contractions, and 13 studies assessed MP by isotonic contractions. We were unable to perform a meta-analysis due to the high heterogeneity among the included studies. In an individual study level analysis, we identified that 14 studies found positive effects of chronic stretching on MP. The improvements were observed only in functional tests and isotonic contractions, isometric contractions were not affected by FT. Therefore, FT might have an influence on dynamic MP. However, more studies are necessary to confirm whether FT can positively affect MP.


Subject(s)
Exercise/physiology , Muscle Stretching Exercises/methods , Muscle, Skeletal/physiology , Adolescent , Athletic Performance/physiology , Female , Humans , Isometric Contraction/physiology , Male , Range of Motion, Articular/physiology , Sports/physiology , Young Adult
8.
Interação psicol ; 20(1): 49-58, jan.-abr. 2016. tab
Article in Portuguese | Index Psychology - journals | ID: psi-69546

ABSTRACT

Este estudo teve por objetivo avaliar a memória de crianças que executam atividades musicais.Participaram 32 crianças, de 7 a 1 2 anos. Destas, 1 6 faziam aulas de música (condição experimental; M=9,81 anos; DP = 0,84) e as outras 1 6 não o faziam (condição controle; M= 9,63 anos; DP = 1 ,82). Foramutilizados o teste pictórico de memória (Tepic-M) e um questionário sociodemográfico. Realizam-seanálises descritivas e o teste t de Student de amostras independentes. A condição experimental apresentoumédia superior (M= 11 ,63, DP = 3,07) em relação à condição controle (M= 8, DP = 3,58), obtendo-seuma diferença estatisticamente significativa entre os grupos [t(22) = 3,07, p<0,05]. Destarte, sugere-seque a execução musical possa beneficiar a memória de curto prazo(AU)


Subject(s)
Humans , Male , Female , Child , Memory, Short-Term , Music , Psychology, Child
9.
J Clin Pharm Ther ; 40(1): 41-7, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25346459

ABSTRACT

WHAT IS KNOWN AND OBJECTIVE: Use of cisplatin can induce type I hypersensitivity reactions that may also be linked to the quality of the drug utilized. We observed cases of hypersensitivity that appeared to be associated with the brand of cisplatin used. The aim of this study was to compare two different brands of cisplatin in relation to type I hypersensitivity reactions. METHODS: Brand A was used in a tertiary care teaching hospital until 2012, and use of brand B started from January 2013, when the first hypersensitivity cases were observed. Patients were categorized based on symptom. Cisplatin of both brands was analysed by high-performance liquid chromatography (HPLC) and high-resolution electrospray ionization mass spectrometry (ESI-(+)-MS) and characterized according to US Pharmacopeia. RESULTS AND DISCUSSION: There were no cases of hypersensitivity associated with the use of cisplatin brand A, whereas four of 127 outpatients that used cisplatin brand B were affected. The two brands were in accordance with the US Pharmacopeia parameters, and there was no significant difference in the total platinum levels between the two brands when analysed by HPLC. However, high-resolution ESI-(+)-MS analyses show that brand B contains approximately 2.7 times more hydrolysed cisplatin than brand A. WHAT IS NEW AND CONCLUSION: The increase in the hydrolysed form of cisplatin found in brand B may be the cause of the hypersensitivity reaction observed in a subset of patients. We present the first study of the quality of drugs by high-resolution ESI-(+)-MS. Drug regulatory agencies and manufacturers should consider including measurement of hydrolysed cisplatin as a quality criterion for cisplatin formulations.


Subject(s)
Cisplatin/adverse effects , Cisplatin/chemistry , Drug Compounding/methods , Drug Hypersensitivity/etiology , Platinum/chemistry , Antineoplastic Agents/adverse effects , Antineoplastic Agents/chemistry , Chemistry, Pharmaceutical/methods , Chromatography, High Pressure Liquid/methods , Drug Hypersensitivity/prevention & control , Female , Humans , Male , Middle Aged , Spectrometry, Mass, Electrospray Ionization/methods
10.
Phytomedicine ; 18(12): 1013-23, 2011 Sep 15.
Article in English | MEDLINE | ID: mdl-21665449

ABSTRACT

The aims of this study was to evaluate the effects of oil-resin of Copaiba (Copaifera duckei Dwyer), aired in vaginal cream on the reproductive performance of female rats (Rattus norvegicus). To determine the components of the C. duckei oleoresin, gas chromatography coupled with mass spectrometry (CG-MS) was used, and considering the trans-caryophyllene sesquiterpene as a phytochemical marker in the oleoresin. Due to the extensive use of copaiba oleoresin in the suppository form for gynecological infections, an evaluation was carried out on the effects of copaiba oleoresin (Copaifera duckei Dwyer), delivered in a vaginal cream, on the reproductive performance of female Wistar rats. For this purpose, three groups (n=5-6/group) of female rats were treated as follows: 1--vaginal cream of copaiba oleoresin (28.6 mg/kg), 2--base vaginal cream and 3--control (physiological saline 0.9%), administered intravaginally, for 30 days before pregnancy, and from day zero to day 20 during pregnancy. Laparotomy was performed on the 21st day of pregnancy, followed by the determination of reproductive variables: number of live and dead fetuses, mass of the fetuses and placentas, number of implantations and resorptions, number of corpora lutea, pre- and post-implantation loss, and analyses of the fetuses with regard to external and internal anomalies and/or malformations (skeletal and visceral). The trans-caryophyllene present in the sample is suggested as a phytochemical marker and the results of this study demonstrate an absence of maternal toxicity and foetotoxicity embryofoetotoxicity at the dose administered, corresponding to ten times the recommended dose for use in humans. Accordingly, no significant statistical difference was observed between the treated and control groups, for the variables analyzed. Thus, it is concluded that the vaginal cream containing 2.5% copaiba oleoresin is safe during gestation, in female rats (Rattus norvegicus) of the Wistar strain.


Subject(s)
Plant Preparations/administration & dosage , Reproduction/drug effects , Abnormalities, Drug-Induced , Administration, Intravaginal , Animals , Animals, Newborn/abnormalities , Chromatography, Gas , Drug Evaluation, Preclinical , Female , Fetal Resorption/chemically induced , Fetal Weight/drug effects , Male , Organ Size/drug effects , Osteogenesis/drug effects , Placenta/drug effects , Plant Preparations/chemistry , Plant Preparations/toxicity , Plants, Medicinal/chemistry , Pregnancy , Rats , Rats, Wistar
12.
Article in English | MEDLINE | ID: mdl-22256179

ABSTRACT

This paper is concerned with the automatic control of drug administration in patients suffering from Brugada Syndrome (BS). Drugs such as flecainide, procainamide, ajmaline and pilsicainide should be administrated under carefully controlled electrocardiogram (ECG) monitoring given that the treatment must be stopped if some ECG disturbing conditions appear. These conditions are, among others the development of premature ventricular contraction (PVC), atrial fibrillation (AF) and the widening of the QRS wave. The proposed system can detect these abnormalities by using a pattern recognition approach based on Hidden Markov Models (HMM) with features extracted from three scales of the Wavelet Transform (WT). Performances higher than 98% were reached regarding the classification of normal and abnormal pulses. The system was trained and tested mainly in data from the standard MIT-BIH arrhythmia database.


Subject(s)
Brugada Syndrome/drug therapy , Brugada Syndrome/physiopathology , Electrocardiography/instrumentation , Monitoring, Physiologic/instrumentation , Anti-Arrhythmia Agents/therapeutic use , Automation , Humans , Markov Chains , Pulse , Wavelet Analysis
13.
Article in English | MEDLINE | ID: mdl-21096243

ABSTRACT

This article is concerned with the classification of ECG pulses by using state of the art Continuous Density Hidden Markov Models (CDHMM's). The ECG signal is simultaneously observed at three different level of focus by means of the Wavelet Transform (WT). The types of beat being selected are normal (N), premature ventricular contraction (V) which is often precursor of ventricular arrhythmia, two of the most common class of supra-ventricular arrhythmia (S), named atrial fibrillation (AF), atrial flutter (AFL), and normal rhythm (N). Both MLII and V1 derivations are used. Run time classification errors can be detected at the decoding stage if the classification of each derivation is different. These pulses are selected for a posterior physician analysis. Experimental results were obtained in real data from MIT-BIH Arrhythmia Database and also in data acquired from a developed low-cost Data-Acquisition System.


Subject(s)
Algorithms , Arrhythmias, Cardiac/diagnosis , Diagnosis, Computer-Assisted/methods , Electrocardiography/methods , Pattern Recognition, Automated/methods , Wavelet Analysis , Arrhythmias, Cardiac/classification , Artificial Intelligence , Computer Simulation , Data Interpretation, Statistical , Humans , Markov Chains , Models, Statistical , Reproducibility of Results , Sensitivity and Specificity
14.
Article in English | MEDLINE | ID: mdl-19964839

ABSTRACT

This paper reports a comparative study of feature extraction methods regarding cardiac arrhythmia classification, using state of the art Hidden Markov Models. The types of beat being selected are normal (N), premature ventricular contraction (V) which is often precursor of ventricular arrhythmia, two of the most common class of supra-ventricular arrhythmia (S), named atrial fibrillation (AF), atrial flutter (AFL), and normal rhythm (N). The considered feature extraction methods are the standard linear segmentation and wavelet based feature extraction. The followed approach regarding wavelets was to observe simultaneously the signal at different scales, which means with different level of focus. Experimental results are obtained in real data from MIT-BIH Arrhythmia Database and show that wavelet transform outperforms the conventional standard linear segmentation.


Subject(s)
Arrhythmias, Cardiac/classification , Markov Chains , Algorithms , Atrial Fibrillation/classification , Atrial Flutter/classification , Humans
15.
Am J Epidemiol ; 170(10): 1207-21, 2009 Nov 15.
Article in English | MEDLINE | ID: mdl-19846566

ABSTRACT

Worldwide, over 1 million cases of colorectal cancer (CRC) were reported in 2002, with a 50% mortality rate, making CRC the second most common cancer in adults. Certain racial/ethnic populations continue to experience a disproportionate burden of CRC. A common polymorphism in the 5,10-methylenetetrahydrofolate reductase (MTHFR) gene has been associated with a lower risk of CRC. The authors performed both a meta-analysis (29 studies; 11,936 cases, 18,714 controls) and a pooled analysis (14 studies; 5,068 cases, 7,876 controls) of the C677T MTHFR polymorphism and CRC, with stratification by racial/ethnic population and behavioral risk factors. There were few studies on different racial/ethnic populations. The overall meta-analysis odds ratio for CRC for persons with the TT genotype was 0.83 (95% confidence interval (CI): 0.77, 0.90). An inverse association was observed in whites (odds ratio = 0.83, 95% CI: 0.74, 0.94) and Asians (odds ratio = 0.80, 95% CI: 0.67, 0.96) but not in Latinos or blacks. Similar results were observed for Asians, Latinos, and blacks in the pooled analysis. The inverse association between the MTHFR 677TT polymorphism and CRC was not significantly modified by smoking status or body mass index; however, it was present in regular alcohol users only. The MTHFR 677TT polymorphism seems to be associated with a reduced risk of CRC, but this may not hold true for all populations.


Subject(s)
Colorectal Neoplasms/genetics , Methylenetetrahydrofolate Reductase (NADPH2)/genetics , Polymorphism, Single Nucleotide , Colorectal Neoplasms/enzymology , Colorectal Neoplasms/epidemiology , Confidence Intervals , Epidemiologic Methods , Gene Frequency , Logistic Models , Methylenetetrahydrofolate Reductase (NADPH2)/metabolism , NADP/genetics , NADP/metabolism , Odds Ratio , Risk Factors , United States/epidemiology
16.
Braz. j. med. biol. res ; 42(7): 593-598, July 2009. ilus, tab
Article in English | LILACS | ID: lil-517801

ABSTRACT

Blood and lymphatic vessel proliferation is essential for tumor growth and progression. Most colorectal carcinomas develop from adenomas (adenoma-carcinoma sequence) in a process due to accumulation of molecular genetic alterations. About 5% of adenomatous polyps are expected to become malignant, but data on the differential angiogenic patterns of these lesions in patients with and without concomitant cancer are missing. The aim of the present study is to compare the angiogenic and lymphatic patterns of adenomatous polyps from patients with and without sporadic cancer. Thirty adenomatous polyps (15 from patients with another principal malignant lesion, and 15 from patients without cancer) were submitted to immunohistochemical staining for CD105 (marker for neoangiogenesis) and D2-40 (marker for lymphatic endothelium). Microvessel density and total vascular area were determined by computer image analysis to quantify the immunostained and total areas, and to assess the number of microvessels. Adenomas from patients with carcinoma showed significantly higher values of total vascular area determined by immunostaining for CD105 (cutoff value = 4386 µm²; P = 0.019) and of lymphatic microvessel density determined by immunostaining with D2-40 (cutoff value = 11.5; P = 0.041) when compared with those from patients without cancer. The present data indicate a significant increase in blood microvascular area and in lymphatic microvascular counts in adenomas removed from patients with cancer.


Subject(s)
Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Adenomatous Polyps/pathology , Colorectal Neoplasms/pathology , Lymphangiogenesis/physiology , Neovascularization, Pathologic/pathology , Adenomatous Polyps/blood supply , Adenomatous Polyps/chemistry , Antibodies, Monoclonal/analysis , Antigens, CD/analysis , Biomarkers/analysis , Colorectal Neoplasms/blood supply , Colorectal Neoplasms/chemistry , Immunohistochemistry , Lymphatic Vessels/chemistry , Lymphatic Vessels/pathology , Microcirculation , Retrospective Studies , Receptors, Cell Surface/analysis
17.
Neuroscience ; 162(4): 1174-86, 2009 Sep 15.
Article in English | MEDLINE | ID: mdl-19465085

ABSTRACT

Relapse to drug use is a major public health problem. In this sense, understanding the biological substrates that are affected during withdrawal may provide information to prevent relapse. Both smoking and alcoholic beverage consumption usually begin during adolescence, however, little is known about the basic neurobiology of the combined adolescent exposure, particularly during withdrawal. Since nicotine is a cholinergic agonist and it has been shown that ethanol interferes with nicotinic acetylcholine receptors (nAChRs), the current study focused on the effects of drug withdrawal on the central cholinergic system. From the 30th to the 45th postnatal day (PN), C57BL/6 male and female mice were exposed to nicotine free base (NIC) and/or ethanol (ETOH). Four groups were analyzed: (1) concomitant NIC (50 microg/ml in 2% saccharin to drink) and ETOH (25%, 2 g/kg i.p. injected every other day) exposure; (2) NIC exposure; (3) ETOH exposure; (4) vehicle. We assessed nAChR binding, choline acetyltransferase (ChAT) activity and [(3)H]hemicholinium-3 (HC-3) binding in the cerebral cortex and midbrain of mice at short (PN50) and long term (PN75) withdrawal. NIC and NIC+ETOH promoted nAChR upregulation during a short-term withdrawal. NIC short-term withdrawal elicited an increase in ChAT activity that was reversed by ETOH withdrawal. In addition, NIC+ETOH elicited a decrease in ChAT activity at long term withdrawal. Regarding HC-3, ETOH and NIC+ETOH promoted a decrease that persisted at long-term withdrawal. The present study provides experimental evidence that nicotine and ethanol during adolescence interact resulting in cholinergic system alterations during withdrawal.


Subject(s)
Choline O-Acetyltransferase/metabolism , Ethanol/pharmacology , Membrane Transport Proteins/metabolism , Nicotine/pharmacology , Receptors, Nicotinic/metabolism , Substance Withdrawal Syndrome/metabolism , Age Factors , Animals , Biomarkers/metabolism , Body Weight/drug effects , Brain/drug effects , Brain/growth & development , Brain/metabolism , Cotinine/blood , Drinking/drug effects , Drug Interactions , Ethanol/adverse effects , Ethanol/blood , Female , Male , Mice , Mice, Inbred C57BL , Nicotine/adverse effects , Protein Binding , Radioligand Assay , Substance Withdrawal Syndrome/etiology , Synapses/physiology , Time Factors
18.
Braz J Med Biol Res ; 42(7): 593-8, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19466284

ABSTRACT

Blood and lymphatic vessel proliferation is essential for tumor growth and progression. Most colorectal carcinomas develop from adenomas (adenoma-carcinoma sequence) in a process due to accumulation of molecular genetic alterations. About 5% of adenomatous polyps are expected to become malignant, but data on the differential angiogenic patterns of these lesions in patients with and without concomitant cancer are missing. The aim of the present study is to compare the angiogenic and lymphatic patterns of adenomatous polyps from patients with and without sporadic cancer. Thirty adenomatous polyps (15 from patients with another principal malignant lesion, and 15 from patients without cancer) were submitted to immunohistochemical staining for CD105 (marker for neoangiogenesis) and D2-40 (marker for lymphatic endothelium). Microvessel density and total vascular area were determined by computer image analysis to quantify the immunostained and total areas, and to assess the number of microvessels. Adenomas from patients with carcinoma showed significantly higher values of total vascular area determined by immunostaining for CD105 (cutoff value = 4386 microm(2); P = 0.019) and of lymphatic microvessel density determined by immunostaining with D2-40 (cutoff value = 11.5; P = 0.041) when compared with those from patients without cancer. The present data indicate a significant increase in blood microvascular area and in lymphatic microvascular counts in adenomas removed from patients with cancer.


Subject(s)
Adenomatous Polyps/pathology , Colorectal Neoplasms/pathology , Lymphangiogenesis/physiology , Neovascularization, Pathologic/pathology , Adenomatous Polyps/blood supply , Adenomatous Polyps/chemistry , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal/analysis , Antibodies, Monoclonal, Murine-Derived , Antigens, CD/analysis , Biomarkers/analysis , Colorectal Neoplasms/blood supply , Colorectal Neoplasms/chemistry , Endoglin , Female , Humans , Immunohistochemistry , Lymphatic Vessels/chemistry , Lymphatic Vessels/pathology , Male , Microcirculation , Middle Aged , Receptors, Cell Surface/analysis , Retrospective Studies
19.
Article in English | MEDLINE | ID: mdl-19162661

ABSTRACT

This paper is concerned with the segmentation of the second heart sound (S2) of the phonocardiogram (PCG), in its two acoustic events, aortic (A2) and pulmonary (P2) components. The aortic valve (A2) usually closes before the pulmonary valve (P2) and the delay between these two events is known as 'split' and is typically less than 30 miliseconds. S2 splitting, reverse splitting or reverse occurrence of components A2 and P2 are the most important aspects regarding cardiac diagnosis carried out by the analysis of S2 cardiac sound. An automatic technique, based on discrete wavelet transform and hidden Markov models, is proposed in this paper to segment S2, to estimate de order of occurrence of A2 and P2 and finally to estimate the delay between these two components (split). A discrete density hidden Markov model (DDHMM) is used for phonocardiogram segmentation while embedded continuous density hidden Markov models are used for acoustic models, which allows segmenting S2. Experimental results were evaluated on data collected from five different subjects, using CardioLab system and a Dash family patient monitor. The ECG leads I, II and III and an electronic stethoscope signal were sampled at 977 samples per second.


Subject(s)
Algorithms , Artificial Intelligence , Diagnosis, Computer-Assisted/methods , Models, Cardiovascular , Pattern Recognition, Automated/methods , Phonocardiography/methods , Computer Simulation , Humans , Markov Chains , Models, Statistical , Reproducibility of Results , Sensitivity and Specificity
20.
Article in English | MEDLINE | ID: mdl-19162891

ABSTRACT

This paper presents a system to support medical diagnosis and detection of abnormal lesions by processing capsule endoscopic images. Endoscopic images possess rich information expressed by texture. Texture information can be efficiently extracted from medium scales of the wavelet transform. The set of features proposed in this paper to code textural information is named color wavelet covariance (CWC). CWC coefficients are based on the covariances of second order textural measures, an optimum subset of them is proposed. Third and forth order moments are added to cope with distributions that tend to become non-Gaussian, especially in some pathological cases. The proposed approach is supported by a classifier based on radial basis functions procedure for the characterization of the image regions along the video frames. The whole methodology has been applied on real data containing 6 full endoscopic exams and reached 95% specificity and 93% sensitivity.


Subject(s)
Capsule Endoscopy/methods , Gastrointestinal Tract/pathology , Image Processing, Computer-Assisted , Crohn Disease/diagnosis , Crohn Disease/pathology , Data Interpretation, Statistical , Gastrointestinal Hemorrhage/diagnosis , Gastrointestinal Hemorrhage/pathology , Humans , Intestinal Neoplasms/diagnosis , Intestinal Neoplasms/pathology , Intestinal Polyps/diagnosis , Intestinal Polyps/pathology , Intestine, Small/pathology , Lymphoma/diagnosis , Lymphoma/pathology , Neural Networks, Computer , Pattern Recognition, Automated , Sensitivity and Specificity
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