120 research outputs found

    Uterine leiomyomas: correlation between histologic composition and stiffness via magnetic resonance elastography — a Pilot Study

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    Objectives: To evaluate magnetic resonance elastography as a tool for characterizing uterine leimyomas.Material and methods: At total of 12 women with symptomatic leiomyomas diagnosed in physical and ultrasound examinationswere enrolled in this pilot study. Before surgery, all patients underwent magnetic resonance elastography ofthe uterus using a 1.5 T MR whole-body scanner (Optima, GE Healthcare, Milwaukee, WI, USA). Surgical specimens wereforwarded for histological examination. The findings were allocated into 3 categories depending on the percentage contentof connective tissue: below 15%, from 15 to 30% and more than 30%. The median stiffness of leiomyomas for each of thegroup was calculated. The U-Mann Whitney test was used for statistical analysis.Results: The stiffness of the leiomyomas ranged between 3.7–6.9 kPa (median value 4.9 kPa). The concentration of extracellularcomponents in the leiomyomas did not exceed 40%. An increasing trend of the stiffness with the growing percentageof extracellular component was observed. Stiffness of the leiomyomas obtained by MRE varies depending on microscopiccomposition.Conclusions: The value of stiffness shows a trend of increasing with the percentage of extracellular component of theleiomyoma. Further studies are required to assess the usefulness of MRE in diagnostics of uterine leiomyomas

    Pnpla3 single nucleotide polymorphism prevalence and association with liver disease in a diverse cohort of persons living with hiv

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    In persons living with HIV (PLWH), there are multiple sources of liver injury. Gene polymorphisms of PNPLA3 (patatin-like phospholipase domain-containing protein 3) have been identified as an important cofactor for increased disease severity in both alcoholic and non-alcoholic steatohepatitis (NASH). We utilized a well-characterized cohort of ethnically and racially diverse patients with HIV to define the prevalence of PNPLA3 SNPs (single nucleotide polymorphism) (rs738409), and to determine the relationship to hepatic steatosis and liver fibrosis. Steatosis was determined using MRI-PDFF (magnetic resonance imaging-determined proton density fat fraction) and fibrosis was estimated using MR Elastography (MRE). From the Miami Area HIV Study (MASH) cohort, 100 HIV positive participants and 40 controls (HCV/HIV = 20; HCV and HIV negative = 20) were evaluated. Nearly 40% of all participants carried the variant G allele associated with increased liver disease severity and 5% were homozygotic GG. The variant SNP occurred most frequently in those self-identified as Hispanic compared to white or Black participants. Hepatic steatosis (\u3e5% fat) was present significantly more often in those without HIV vs. those with (p \u3c 0.001). Putative NAFLD/NASH was found to be present in 6% of tested subjects, who were HIV monoinfected. BMI was lower in those that carried the G allele for PNPLA3. This finding suggests that PNPLA3 may be an independent component to NAFLD (non-alcoholic fatty liver disease)/NASH development and longitudinal follow-up of the cohort is warranted

    The Dynamics of Democracy, Development and Cultural Values

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    Over the past decades many countries have experienced rapid changes in their economies, their democratic institutions and the values of their citizens. Comprehensive data measuring these changes across very different countries has recently become openly available. Between country similarities suggest common underlying dynamics in how countries develop in terms of economy, democracy and cultural values. We apply a novel Bayesian dynamical systems approach to identify the model which best captures the complex, mainly non-linear dynamics that underlie these changes. We show that the level of Human Development Index (HDI) in a country drives first democracy and then higher emancipation of citizens. This change occurs once the countries pass a certain threshold in HDI. The data also suggests that there is a limit to the growth of wealth, set by higher emancipation. Having reached a high level of democracy and emancipation, societies tend towards equilibrium that does not support further economic growth. Our findings give strong empirical evidence against a popular political science theory, known as the Human Development Sequence. Contrary to this theory, we find that implementation of human-rights and democratisation precede increases in emancipative values

    Increased serum miR-193a-5p during non-alcoholic fatty liver disease progression: diagnostic and mechanistic relevance

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    Background & Aims: Serum microRNAs (miRNAs) levels are known to change in non-alcoholic fatty liver disease (NAFLD) and may serve as useful biomarkers. This study aimed to profile miRNAs comprehensively at all NAFLD stages.Methods: We profiled 2,083 serum miRNAs in a discovery cohort (183 NAFLD cases representing the complete NAFLD spectrum and 10 population controls). MiRNA libraries generated by HTG EdgeSeq were sequenced by Illumina NextSeq. Selected serum miRNAs were profiled in 372 additional NAFLD cases and 15 population controls by quantitative reverse transcriptase-polymerase chain reaction.Results: Levels of 275 miRNAs differed between cases and population controls. Fewer differences were seen within individual NAFLD stages but miR-193a-5p consistently the showed increased levels in all comparisons. Relative to NAFL/NASH with mild fibrosis (stage 0/1), three miRNAs (miR-193a-5p, miR-378d and miR378d) were increased in cases with NASH and clinically significant fibrosis (stage 2-4), seven (miR193a-5p, miR-378d, miR-378e, miR-320b, c, d & e) increased in cases with NAFLD Activity Score (NAS) 5-8 compared with lower NAS, and three (miR-193a-5p, miR-378d, miR-378e) increased but one (miR-19b-3p) decreased in steatosis, activity, and fibrosis "activity" (SAF-A) score 2-4 compared with lower SAF-A. The significant findings for miR-193a-5p were replicated in the additional NAFLD cohort. Studies in Hep G2 cells showed that following palmitic acid treatment, miR-193a-5p expression decreased significantly. Gene targets for miR-193a-5p were investigated in liver RNAseq data for a case subgroup (n=80); liver GPX8 levels correlated positively with serum miR-193a-5p. Conclusions: Serum miR-193a-5p levels correlate strongly with NAFLD activity grade and fibrosis stage. MiR-193a-5p may have a role in the hepatic response to oxidative stress and is a potential clinically tractable circulating biomarker for progressive NAFLD

    Performance of non-invasive tests and histology for the prediction of clinical outcomes in patients with non-alcoholic fatty liver disease: an individual participant data meta-analysis

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    BackgroundHistologically assessed liver fibrosis stage has prognostic significance in patients with non-alcoholic fatty liver disease (NAFLD) and is accepted as a surrogate endpoint in clinical trials for non-cirrhotic NAFLD. Our aim was to compare the prognostic performance of non-invasive tests with liver histology in patients with NAFLD.MethodsThis was an individual participant data meta-analysis of the prognostic performance of histologically assessed fibrosis stage (F0–4), liver stiffness measured by vibration-controlled transient elastography (LSM-VCTE), fibrosis-4 index (FIB-4), and NAFLD fibrosis score (NFS) in patients with NAFLD. The literature was searched for a previously published systematic review on the diagnostic accuracy of imaging and simple non-invasive tests and updated to Jan 12, 2022 for this study. Studies were identified through PubMed/MEDLINE, EMBASE, and CENTRAL, and authors were contacted for individual participant data, including outcome data, with a minimum of 12 months of follow-up. The primary outcome was a composite endpoint of all-cause mortality, hepatocellular carcinoma, liver transplantation, or cirrhosis complications (ie, ascites, variceal bleeding, hepatic encephalopathy, or progression to a MELD score ≥15). We calculated aggregated survival curves for trichotomised groups and compared them using stratified log-rank tests (histology: F0–2 vs F3 vs F4; LSM: 2·67; NFS: 0·676), calculated areas under the time-dependent receiver operating characteristic curves (tAUC), and performed Cox proportional-hazards regression to adjust for confounding. This study was registered with PROSPERO, CRD42022312226.FindingsOf 65 eligible studies, we included data on 2518 patients with biopsy-proven NAFLD from 25 studies (1126 [44·7%] were female, median age was 54 years [IQR 44–63), and 1161 [46·1%] had type 2 diabetes). After a median follow-up of 57 months [IQR 33–91], the composite endpoint was observed in 145 (5·8%) patients. Stratified log-rank tests showed significant differences between the trichotomised patient groups (p<0·0001 for all comparisons). The tAUC at 5 years were 0·72 (95% CI 0·62–0·81) for histology, 0·76 (0·70–0·83) for LSM-VCTE, 0·74 (0·64–0·82) for FIB-4, and 0·70 (0·63–0·80) for NFS. All index tests were significant predictors of the primary outcome after adjustment for confounders in the Cox regression.InterpretationSimple non-invasive tests performed as well as histologically assessed fibrosis in predicting clinical outcomes in patients with NAFLD and could be considered as alternatives to liver biopsy in some cases

    Mandatory dedication of park and open space land: effectiveness of and attitudes toward this method of public land acquisition in Texas

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    Due to the character of the original source materials and the nature of batch digitization, quality control issues may be present in this document. Please report any quality issues you encounter to [email protected], referencing the URI of the item.Bibliography: leaves 94-98.Not availabl

    Armando Manduca

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    We have explored the use of artificial neural networks to diagnose avascular necrosis (AVN) of the femoral head from magnetic resonance images. We have developed multi-layer perceptron networks, trained with conjugate gradient optimization, which diagnose AVN from single sagittal images of the femoral head with 100% accuracy on the training data and 97% accuracy on test data. These networks use only the raw image as input (with minimal preprocessing to average the images down to 32x32 size and to scale the input data values) and learn to extract their own features for the diagnosis decision. Various experiments with these networks are described. 1. INTRODUCTION Diagnostic radiology may be a very natural field of application for neural networks, since a simple answer is desired from a complex image, and the learning process that human experts undergo is to a large extent a supervised learning experience based on looking at large numbers of images with known interpretations. Although ma..

    Advanced MRI Methods for Assessment of Chronic Liver Disease

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    Applications of Magnetic Resonance Elastography to Healthy and Pathologic Skeletal Muscle

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    Magnetic resonance elastography (MRE) Is capable of non-invasively quantifying the mechanical properties of skeletal muscles in vivo. This information can be clinically useful to understand the effects of pathologies on the mechanical properties of muscle and to quantify the effects of treatment. Advances in inversion algorithms quantify muscle anisotropy in two-dimensional (2D) and three-dimensional (3D) imaging. Databases of the shear stiffness of skeletal muscle have been presented in the relaxed and contracted states in the upper extremity (biceps brachii, flexor digitorum profundus, and upper trapezius), distal leg muscles (tibialis anterior, medial gastrocnemius, lateral gastrocnemius, and trapezius), and proximal leg muscles (vastus lateralis, vastus medialis, and sartorius). MRE measurements have successfully validated a mathematical model of skeletal muscle behavior in the biceps brachii, correlated to electromyographic data in the distal leg muscles and quantified the effects of pathologies on the distal and proximal leg muscles. Future research efforts should be directed toward improving one-dimensional (1D) and 3D MRE data acquisition and image processing, tracking the effects of treatment on pathologic muscle and correlating the shear stiffness with clinical measurements
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