250 research outputs found

    Fat Quantitation in Liver Biopsies Using a Pretrained Classification Based System

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    Non-Alcoholic Fatty Liver Disease (NAFLD) is a common syndrome that mainly leads to fat accumulation in liver and steatohepatitis. It is targeted as a severe medical condition ranging from 20% to 40% in adult populations of the Western World. Its effect is identified through insulin resistance, which places patients at high mortality rates. An increased fat aggregation rate, can dramatically increase the development of liver steatosis, which in later stages may advance into fibrosis and cirrhosis. During recent years, new studies have focused on building new methodologies capable of detecting fat cells, based on the histology method with digital image processing techniques. The current study, expands previous work on the detection of fatty liver, by identifying once more a number of diverse histological findings. It is a combined study of both image analysis and supervised learning of fat droplet features, with a specific goal to exclude other findings from fat ratio calculation. The method is evaluated in a total set of 40 liver biopsy images with different magnification capabilities, performing satisfyingly (1.95% absolute error)

    Effects of sex, age, body height and body weight on spinal loads: sensitivity analyses in a subject-specific trunk musculoskeletal model.

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    Subject-specific parameters influence spinal loads and the risk of back disorders but their relative effects are not well understood. The objective of this study is to investigate the effects of changes in age (35-60 years), sex (male, female), body height (BH: 150-190 cm) and body weight (BW: 50-120 kg) on spinal loads in a full factorial simulation using a personalized (spine kinematics, geometry, musculature and passive properties) kinematics driven musculoskeletal trunk finite element model. Segmental weight distribution (magnitude and location along the trunk) was estimated by a novel technique to accurately represent obesity. Five symmetric sagittal loading conditions were considered, and main effect plots and analyses of variance were employed to identify influential parameters. In all 5 tasks simulated, BW (98.9% in compression and 96.1% in shear) had the greatest effect on spinal loads at the L4-L5 and L5-S1 levels followed by sex (0.7% in compression and 2.1% in shear), BH (0.4% in compression and 1.5% in shear) and finally age (<5.4%). At identical BH and BW, spinal loads in females were slightly greater than those in males by ~4.7% in compression and ~8.7% in shear. In tasks with no loads in hands, BW-normalized spinal loads further increased with BW highlighting the exponential increase in spinal loads with BW that indicates the greater risk of back disorders especially in obese individuals. Uneven distribution of weight in obese subjects, with more BW placed at the lower trunk, further (though slightly <7.5%) increased spinal loads.This work was supported by the institut de recherche Robert-Sauvé en santé et en sécurité du travail 294 (IRSST-2014-0009) and the fonds de recherche du Québec en nature et technologies (FRQNT)

    A model-based approach for estimation of changes in lumbar segmental kinematics associated with alterations in trunk neuromuscular strategy

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    This is the author accepted manuscript. The final version is available from Elsevier via the DOI in this recordThe geometrical information from imaging, if combined with optimization-based methods of neuromuscular assessment, may provide a unique platform for personalized assessment of trunk neuromuscular behavior. Such a method, however, is feasible only if differences in lumbar spine kinematics due to differences in trunk neuromuscular behavior can be captured by the current imaging techniques. A finite element model of the spine within an optimization procedure was used to estimate segmental kinematics of lumbar spine associated with five different hypothetical trunk neuromuscular strategies (TNSs). Each TNS optimized one aspect of lower back biomechanics and was assumed to either represent the TNS of asymptomatic persons or a neuromuscular abnormality. For each TNS, the segmental kinematics of lumbar spine was estimated for a single static trunk flexed posture involving, respectively, 40° and 10° of thoracic and pelvic rotations. Minimum changes in the angular and translational deformations of a motion segment with alterations in TNS ranged from 0° to 0.5° and 0 mm to 0.04 mm, respectively. Maximum changes in the angular and translational deformations of a motion segment with alterations in neuromuscular strategy ranged from 2.4° to 7.5° and 0.11 mm to 0.39 mm, respectively. The differences in kinematics of lumbar segments between each combination of two TNSs in 97% of cases for angular deformation and 55% of cases for translational deformation were within the reported accuracy of current imaging techniques. Combined imaging and computational modeling appears to have potentials for predicting alterations in neuromuscular strategies.This work was supported, in part, by an award (5R03HD086512-02) from the National Center for Medical Rehabilitation Research (NIH-NICHD) and the Office of the Assistant Secretary of Defense for Health Affairs, through the Peer Reviewed Orthopaedic Research Program (award #W81XWH-14-2-0144)

    Quantification of liver fibrosis—a comparative study

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    Liver disease has been targeted as the fifth most common cause of death worldwide and tends to steadily rise. In the last three decades, several publications focused on the quantification of liver fibrosis by means of the estimation of the collagen proportional area (CPA) in liver biopsies obtained from digital image analysis (DIA). In this paper, early and recent studies on this topic have been reviewed according to these research aims: the datasets used for the analysis, the employed image processing techniques, the obtained results, and the derived conclusions. The purpose is to identify the major strengths and “gray-areas” in the landscape of this topic

    VectorDisk: a microfluidic platform integrating diagnostic markers for evidence-based mosquito control

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    Effective mosquito monitoring relies on the accurate identification and characterization of the target population. Since this process requires specialist knowledge and equipment that is not widely available, automated field-deployable systems are highly desirable. We present a centrifugal microfluidic cartridge, the VectorDisk, which integrates TaqMan PCR assays in two feasibility studies, aiming to assess multiplexing capability, specificity, and reproducibility in detecting disk-integrated vector-related assays. In the first study, pools of 10 mosquitoes were used as samples. We tested 18 disks with 27 DNA and RNA assays each, using a combination of multiple microfluidic chambers and detection wavelengths (geometric and color multiplexing) to identify mosquito and malaria parasite species as well as insecticide resistance mechanisms. In the second study, purified nucleic acids served as samples to test arboviral and malaria infective mosquito assays. Nine disks were tested with 14 assays each. No false positive results were detected on any of the disks. The coe cient of variation in reproducibility tests was <10%. The modular nature of the platform, the easy adaptation of the primer/probe panels, the cold chain independence, the rapid (2-3 h) analysis, and the assay multiplexing capacity are key features, rendering the VectorDisk a potential candidate for automated vector analysis

    Overview of hydatid disease in Iranian children

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    Background: Hydatid disease (HD) is still an important health hazard in the world. This disease is a parasitic infestation endemic in many sheep- and cattle-raising areas such as Iran. Objectives: This study aimed to review the clinical manifestations, laboratory aspects, imaging findings, and management of HD. Patients and Methods: Data were collected from the medical records of patients diagnosed with HD in eight referral hospitals in different provinces of Iran from 2001 to 2014. Results: Overall, 161 children at a mean age of 9.25 ± 3.37 years (age range = 1 - 15 years old) hospitalized with a definite diagnosis of the hydatid cyst between 2001 and 2014 were studied. The male-to-female ratio was 1.6:1. The most commonly involved organ was the lung (67.1), followed by the liver (44.1) and a combined liver and lung involvement was found in 15.5 of the patients. The cysts were found more frequently in the right lobe of the liver and lung than in the left lobe. The most frequent complaints were fever (35.4) and abdominal pain (31.7), and the most frequent sign was an abdominal mass in the liver involvement and cough in the lung involvement. There was a high eosinophil count (> 500/micL) in 41 of our cases. A high erythrocyte sedimentation rate (> 30) or positive C-reactive protein (based on the qualitative method) was found in 18.6 of the patients and leukocytosis > 15000/micL in 29.2 of the children. Ultrasonography was the main imaging test, with an accuracy rate of 96, and chest X-ray was helpful in 88.6 of the cases. Surgery was performed in 89 of the patients, and selective patients underwent percutaneous aspiration-injection-reaspiration drainage or medical treatment. Conclusions: The lung was the most commonly involved organ in the children recruited in the present study. Given the high probability of multiple organ involvement, we recommend that patients with HD be assessed via ultrasonography and chest X-ray. In endemic regions, unexplained eosinophilia should be considered as a parasitic disease like HD and its complications. © 2015 Pediartric Infections Research Center

    Efficient use of water for irrigation in the upper midwest

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    The objectives of this multidisciplinary interinstitutional regional study on the efficient use of water for irrigation in the upper Midwest were: (1) to determine parameters needed for existing or improved models of crop response; (2) to relate yield response to costs and revenues by assessing the water demand for irrigation; and (3) to study the demand for irrigation, present and projected, and its availability as related to public allocation decisions. From this series of studies it was concluded that: (1) There are many areas of the Midwest with sufficient groundwater and surface water resources to support the development of irrigation. (2) Soil moisture models indicate that only moderate yield response to irrigation can be expected on high moisture soils; on lighter soils and claypan soils, yield response is significant, even in regions with relatively high precipitation. (3) Irrigation and drainage on claypan soils can dramatically increase corn yields. (4) It appears economically worthwhile for the individual farmer operating on moderate soils or on claypan soils to evaluate capital investments in irrigation along with other capital investments. (5) Increases in yields and persistence of alfalfa due to irrigation appear to be insignificant when compared to conventional management practices; further research is needed. A potential, however, appears to exist for improving adaptation of a1 fa1 fa varieties to soil water deficits.U.S. Geological SurveyU.S. Department of the InteriorOpe

    Ensemble convolutional neural network classification for pancreatic steatosis assessment in biopsy images

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    Non-alcoholic fatty pancreas disease (NAFPD) is a common and at the same time not extensively examined pathological condition that is significantly associated with obesity, metabolic syndrome, and insulin resistance. These factors can lead to the development of critical pathogens such as type-2 diabetes mellitus (T2DM), atherosclerosis, acute pancreatitis, and pancreatic cancer. Until recently, the diagnosis of NAFPD was based on noninvasive medical imaging methods and visual evaluations of microscopic histological samples. The present study focuses on the quantification of steatosis prevalence in pancreatic biopsy specimens with varying degrees of NAFPD. All quantification results are extracted using a methodology consisting of digital image processing and transfer learning in pretrained convolutional neural networks for the detection of histological fat structures. The proposed method is applied to 20 digitized histological samples, producing an 0.08% mean fat quantification error thanks to an ensemble CNN voting system and 83.3% mean Dice fat segmentation similarity compared to the semi-quantitative estimates of specialist physicians

    Factors associated with TBS worse than BMD in non-osteoporotic elderly population: Bushehr elderly health program

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    Background: Bone mineral density (BMD) and trabecular bone score (TBS) are moderately correlated. TBS is sometimes used as an adjuvant to BMD in the fracture risk assessment. Some individuals with normal BMD or osteopenia, have more degraded TBS. We aimed to identify factors associated with TBS worse than BMD in the non-osteoporotic elderly population. Methods: The study subjects were selected from 2384 women and men aged ≥60 years participating in the second stage of the Bushehr Elderly Health program, a population-based prospective cohort study in Iran. The BMDs of different sites and the lumbar spine texture were measured using dual-energy X-ray absorptiometry and the TBS algorithm, respectively. Subjects were categorized based on their BMD and TBS status

    Evaluation of different total leishmania amazonensis antigens for the development of a first-generation vaccine formulated with a toll-like receptor-3 agonist to prevent cutaneous leishmaniasis

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    Unfortunately, no any vaccine against leishmaniasis has been developed for human use. Therefore, a vaccine based on total Leishmania antigens could be a good and economic approach; and there are different methodologies to obtain these antigens. However, it is unknown whether the method to obtain the antigens affects the integrity and immune response caused by them. OBJECTIVES: to compare the protein profile and immune response generated by total L. amazonensis antigens (TLA) produced by different methods, as well as to analyse the immune response and protection by a first-generation vaccine formulated with sonicated TLA (sTLA) and polyinosinic:polycytidylic acid [Poly (I:C)]. METHODS: TLA were obtained by four different methodologies and their integrity and immune response were evaluated. Finally, sTLA was formulated with Poly (I:C) and their protective immune response was measured. FINDINGS: sTLA presented a conserved protein profile and induced a strong immune response. In addition, Poly (I:C) improved the immune response generated by sTLA. Finally, sTLA + Poly (I:C) formulation provided partial protection against L. amazonensis infection. MAIN CONCLUSIONS: The protein profile and immune response depend on the methodology used to obtain the antigens. Also, the formulation sTLA + Poly (I:C) provides partial protection against cutaneous leishmaniasis in mice.Fil: Germano, Maria Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Lozano, Esteban Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Sanchez, María Victoria. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Bruna, Flavia Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Garcia Bustos, Maria Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta. Instituto de Patología Experimental. Universidad Nacional de Salta. Facultad de Ciencias de la Salud. Instituto de Patología Experimental; ArgentinaFil: Sosa Lochedino, Arianna Lourdes. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Salomón, María Cristina. Universidad Nacional de Cuyo; ArgentinaFil: Fernandes, Ana Paula. Universidade Federal de Minas Gerais; BrasilFil: Mackern Oberti, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; ArgentinaFil: Cargnelutti, Diego Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mendoza. Instituto de Medicina y Biología Experimental de Cuyo; Argentin
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