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1.
Clin Radiol ; 77(5): e363-e371, 2022 05.
Article in English | MEDLINE | ID: mdl-35260232

ABSTRACT

AIM: To develop a fully automated deep-learning-based approach to measure muscle area for assessing sarcopenia on standard-of-care computed tomography (CT) of the abdomen without any case exclusion criteria, for opportunistic screening for frailty. MATERIALS AND METHODS: This ethically approved retrospective study used publicly available and institutional unselected abdominal CT images (n=1,070 training, n=31 testing). The method consisted of two sequential steps: section detection from CT volume followed by muscle segmentation on single-section. Both stages used fully convolutional neural networks (FCNN), based on a UNet-like architecture. Input data consisted of CT volumes with a variety of fields of view, section thicknesses, occlusions, artefacts, and anatomical variations. Output consisted of segmented muscle area on a CT section at the L3 vertebral level. The muscle was segmented into erector spinae, psoas, and rectus abdominus muscle groups. Output was tested against expert manual segmentation. RESULTS: Threefold cross-validation was used to evaluate the model. Section detection cross-validation error was 1.41 ± 5.02 (in sections). Segmentation cross-validation Dice overlaps were 0.97 ± 0.02, 0.95 ± 0.04, and 0.94 ± 0.04 for erector spinae, psoas, and rectus abdominus, respectively, and 0.96 ± 0.02 for the combined muscle area, with R2 = 0.95/0.98 for muscle attenuation/area in 28/31 hold-out test cases. No statistical difference was found between the automated output and a second annotator. Fully automated processing took <1 second per CT examination. CONCLUSIONS: A FCNN pipeline accurately and efficiently automates muscle segmentation at the L3 vertebral level from unselected abdominal CT volumes, with no manual processing step. This approach is promising as a generalisable tool for opportunistic screening for frailty on standard-of-care CT.


Subject(s)
Deep Learning , Frailty , Sarcopenia , Humans , Image Processing, Computer-Assisted/methods , Muscles , Retrospective Studies , Sarcopenia/diagnostic imaging , Tomography, X-Ray Computed/methods
2.
Sci Rep ; 11(1): 8532, 2021 04 20.
Article in English | MEDLINE | ID: mdl-33879838

ABSTRACT

Automatic craniomaxillofacial (CMF) three dimensional (3D) dense phenotyping promises quantification of the complete CMF shape compared to the limiting use of sparse landmarks in classical phenotyping. This study assesses the accuracy and reliability of this new approach on the human mandible. Classic and automatic phenotyping techniques were applied on 30 unaltered and 20 operated human mandibles. Seven observers indicated 26 anatomical landmarks on each mandible three times. All mandibles were subjected to three rounds of automatic phenotyping using Meshmonk. The toolbox performed non-rigid surface registration of a template mandibular mesh consisting of 17,415 quasi landmarks on each target mandible and the quasi landmarks corresponding to the 26 anatomical locations of interest were identified. Repeated-measures reliability was assessed using root mean square (RMS) distances of repeated landmark indications to their centroid. Automatic phenotyping showed very low RMS distances confirming excellent repeated-measures reliability. The average Euclidean distance between manual and corresponding automatic landmarks was 1.40 mm for the unaltered and 1.76 mm for the operated sample. Centroid sizes from the automatic and manual shape configurations were highly similar with intraclass correlation coefficients (ICC) of > 0.99. Reproducibility coefficients for centroid size were < 2 mm, accounting for < 1% of the total variability of the centroid size of the mandibles in this sample. ICC's for the multivariate set of 325 interlandmark distances were all > 0.90 indicating again high similarity between shapes quantified by classic or automatic phenotyping. Combined, these findings established high accuracy and repeated-measures reliability of the automatic approach. 3D dense CMF phenotyping of the human mandible using the Meshmonk toolbox introduces a novel improvement in quantifying CMF shape.


Subject(s)
Anatomic Landmarks/diagnostic imaging , Cephalometry/methods , Cone-Beam Computed Tomography/methods , Electronic Data Processing/methods , Imaging, Three-Dimensional/methods , Mandible/anatomy & histology , Humans , Mandible/diagnostic imaging , Phenotype , Reproducibility of Results
3.
Ann Hematol ; 99(5): 1025-1030, 2020 May.
Article in English | MEDLINE | ID: mdl-32157420

ABSTRACT

The incidence of multiple myeloma (MM) has increased in the last 20 years, particularly in middle and low-middle income countries. Access to diagnostic and prognostic tests and the availability of effective care is highly variable globally. Latin America represents 10% of the world population, distributed in countries of varied size, population, and socio-economic development. In the last decade, great improvements have been made in the diagnosis and treatment of MM. Applying these advances in real life is a challenge in our region. Local data regarding MM standards of care and outcomes are limited. A survey was carried out among hematologists from 15 Latin American countries to describe access to MM diagnostic and prognostic tests and the availability of effective care options. This study provides real-world data for MM in our region, highlighting striking differences between public and private access to essential analyses and therapeutic options.


Subject(s)
Health Services Accessibility , Multiple Myeloma , Private Practice , Public Health Practice , Surveys and Questionnaires , Cross-Sectional Studies , Latin America/epidemiology , Multiple Myeloma/diagnosis , Multiple Myeloma/epidemiology , Multiple Myeloma/therapy
4.
Anat Histol Embryol ; 47(4): 330-337, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29736911

ABSTRACT

The gill structure of the Amazonian fish Arapaima gigas (Cuvier 1829) shows ontogenetic changes during development, particularly due the transition from the aquatic to the obligatory air breathing mode of respiration. However, three main cell types can be found in the gills: mitochondrial rich cells, pavement cells and mucous cells (MCs). The MCs are involved in the secretory pathway. The functions of the secreted molecules include mechanical protection of epithelia, protection against parasites and bacterial infection, and role on ion regulation. In this study, we analysed mucous cell location and mucous cell type, based on pH, during the development of A. gigas. Using samples obtained from the environment, gills were collected and fixed in buffered solution. Histological techniques for the identification of MCs were performed Alcian Blue (AB) and periodic acid-Schiff (PAS). The results showed the presence of PAS+ and AB+ cells in the whole filament in all examined fish. In animals less than 50 g, few MCs were present, and no differences were observed in AB+ and PAS+ cells. In animals weighing close to 500 g, more PAS+ cells than AB+ cells were observed, and in animals that weighed more than 1,000 g, more AB+ cells than PAS+ cells were observed. These observations may be a result of the ontogenetic changes in the gill epithelia, which can change the osmorespiratory compromise in ion regulation functions as well the glycosaminoglycans secreted by PAS cells, which in large animals can play a role in the protection against parasites and bacterial infection.


Subject(s)
Fishes/growth & development , Gills/cytology , Mucous Membrane/cytology , Animals , Brazil , Gills/growth & development , Lakes , Methacrylates , Microscopy, Electron, Transmission , Respiration , Secretory Vesicles/ultrastructure , Tissue Embedding
5.
West Afr J Med ; 29(6): 417-24, 2010.
Article in English | MEDLINE | ID: mdl-21465452

ABSTRACT

BACKGROUND: Malocclusion, though not life-threatening, is an important public health issue, which has a large impact on the individual, causing discomfort, social and functional limitations. OBJECTIVE: To evaluate objectively orthodontic treatment needs in Nigerian schoolchildren and the impact of malocclusion on their quality of life. METHODS: This cross-sectional study involved schoolchildren aged 12 to 16 years from four randomly selected secondary schools in Lagos, Nigeria. A prestructured questionnaire was administered and a clinical examination was conducted. Occlusal status was assessed for each subject using the Dental Aesthetic Index (DAI). Oral Health Impact Profile-14 (OHIP- 14) was also evaluated. RESULTS: There were 410 (50.9%) females and 395 (49.1%) males aged 12 to 16 years. Mean age was 14.5±1.3 years. Irregularity of teeth was the most prevalent malocclusion. Generalised spacing and midline diastema were seen in 59% and 31% respectively; crowding in 43% of the schoolchildren. Other occlusal anomalies were recorded. There was no statistically significant difference between the sexes. Over one third of the study population did not need treatment, treatment was mandatory in 24.3%, elective in 21% and highly desirable in 17%. More females than males did not need orthodontic treatment. Oral conditions had no effect on the quality of life of 85.3% of the study sample. CONCLUSION: Most Nigerian schoolchildren were found to have a dental appearance that needed orthodontic treatment. However, components of the oral conditions impacted on the quality of life of a few subjects. Psycho-social need is very important in orthodontic diagnosis.


Subject(s)
Malocclusion/epidemiology , Needs Assessment/statistics & numerical data , Quality of Life/psychology , Adolescent , Child , Cross-Sectional Studies , Esthetics, Dental , Female , Humans , Male , Malocclusion/diagnosis , Malocclusion/physiopathology , Malocclusion/psychology , Nigeria/epidemiology , Oral Health , Prevalence , Schools , Sex Distribution , Social Class , Socioeconomic Factors , Surveys and Questionnaires
6.
Odontostomatol Trop ; 30(118): 5-8, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17933355

ABSTRACT

Case report of a 20 year old female patient who presented with Binder's maxillonasal dysplasia. She presented with completely missing premaxilla, nasal bone and septum, there was however no associated cardiac abnormalities, mental retardation or other skeletal deformities. Her principal complaint was the associated missing incisors. The incisors and the premaxilla were satisfactorily replaced with a removable maxillofacial prosthesis.


Subject(s)
Abnormalities, Multiple , Bone Diseases, Developmental/diagnostic imaging , Maxilla/abnormalities , Maxillofacial Abnormalities/diagnostic imaging , Abnormalities, Multiple/diagnostic imaging , Abnormalities, Multiple/rehabilitation , Adult , Anodontia/rehabilitation , Female , Humans , Nasal Bone/abnormalities , Nasal Septum/abnormalities , Radiography , Syndrome
8.
Arq Bras Cardiol ; 65(5): 427-30, 1995 Nov.
Article in Portuguese | MEDLINE | ID: mdl-8729861

ABSTRACT

A 16 year-old female patient on oral contraceptive (gynera-ethynilestradiol+gestadone) for 4 months, presented with acute and severe pulmonary thromboembolism (PT), and was successfully treated with IV streptokinase. The contraceptive use was an importante risk factor for PT and the thrombolytic therapy provided early clinical improvement. Blood pressure, heart rate, and hypoxemia, along with echocardiography and pulmonary arteriography abnormalities, improved after this treatment.


Subject(s)
Contraceptives, Oral/adverse effects , Pulmonary Embolism/chemically induced , Adolescent , Female , Humans , Pulmonary Embolism/diagnostic imaging , Radiography
10.
Braz J Med Biol Res ; 19(6): 763-70, 1986.
Article in English | MEDLINE | ID: mdl-3651628

ABSTRACT

1. The influence of castration on contraction of the guinea pig vas deferens induced by acetylcholine was investigated regarding facilitation of endogenous neurotransmitter release, changes in post-synaptic events and modification in acetylcholine metabolization. 2. Castration prolonged the duration of the isometric contraction of the vas deferens induced by acetylcholine (3 mM) but not the duration of that induced by barium chloride (10 mM). 3. Reserpinization (0.5 mg/kg) of normal and castrated guinea pigs did not change the time-course of acetylcholine-induced contraction in the vas deferens. 4. 4-Aminopyridine (0.05 mM) prolonged the contraction induced by acetylcholine and barium chloride. This effect was blocked by reserpine pretreatment, indicating that in the presence of 4-AP, both acetylcholine and barium release endogenous noradrenaline. Since there was no difference between the effects of 4-AP on organs from normal and castrated animals, prolongation of the acetylcholine-induced contraction is not related to an increase in neutransmitter release. 5. Total cholinesterase and acetylcholinesterase activities were reduced after castration and the time-course of carbachol contraction was not changed. Thus, this decrease in enzyme activity appears to play a relevant role in the prolongation of acetylcholine-induced contraction.


Subject(s)
Acetylcholine/pharmacology , Barium Compounds , Barium/pharmacology , Castration , Chlorides , Isometric Contraction , Muscle Contraction , Vas Deferens/drug effects , Animals , Carbachol/pharmacology , Guinea Pigs , Male , Norepinephrine/metabolism , Vas Deferens/physiology
11.
In. Fraser, Henry S; Hoyos, Michael D. Therapeutics and family medicine update 1985 : proceedings of the continuing medical education symposia in Barbados and Antigua in 1984. Bridgetown, University of the West Indies (Cave Hill). Faculty of Medical Sciences, 1985. p.76-80.
Monography in English | LILACS | ID: lil-142808
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