323 research outputs found

    Segmentation of orbital and periorbital lesions detected in orbital magnetic resonance imaging by deep learning method

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    Purpose: Magnetic resonance imaging (MRI) has a special place in the evaluation of orbital and periorbital lesions. Segmentation is one of the deep learning methods. In this study, we aimed to perform segmentation in orbital and periorbital lesions. Material and methods: Contrast-enhanced orbital MRIs performed between 2010 and 2019 were retrospectively screened, and 302 cross-sections of contrast-enhanced, fat-suppressed, T1-weighted, axial MRI images of 95 patients obtained using 3 T and 1.5 T devices were included in the study. The dataset was divided into 3: training, test, and validation. The number of training and validation data was increased 4 times by applying data augmentation (horizontal, vertical, and both). Pytorch UNet was used for training, with 100 epochs. The intersection over union (IOU) statistic (the Jaccard index) was selected as 50%, and the results were calculated. Results: The 77th epoch model provided the best results: true positives, 23; false positives, 4; and false negatives, 8. The precision, sensitivity, and F1 score were determined as 0.85, 0.74, and 0.79, respectively. Conclusions: Our study proved to be successful in segmentation by deep learning method. It is one of the pioneering studies on this subject and will shed light on further segmentation studies to be performed in orbital MR images

    Gain of function mutation in K(ATP) channels and resulting upregulation of coupling conductance are partners in crime in the impairment of Ca<sup>2+</sup> oscillations in pancreatic ß-cells

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    Gain of function mutations in the pore forming Kir6 subunits of the ATP sensitive K+ channels (K(ATP) channels) of pancreatic β-cells are the major cause of neonatal diabetes in humans. In this study, we show that in insulin secreting mouse β-cell lines, gain of function mutations in Kir6.1 result in a significant connexin36 (Cx36) overexpression, which form gap junctional connections and mediate electrical coupling between β-cells within pancreatic islets. Using computational modeling, we show that upregulation in Cx36 might play a functional role in the impairment of glucose stimulated Ca2+ oscillations in a cluster of β-cells with Kir6.1 gain of function mutations in their K(ATP) channels (GoF-K(ATP) channels). Our results show that without an increase in Cx36 expression, a gain of function mutation in Kir6.1 might not be sufficient to diminish glucose stimulated Ca2+ oscillations in a β-cell cluster. We also show that a reduced Cx36 expression, which leads to loss of coordination in a wild-type β-cell cluster, restores coordinated Ca2+ oscillations in a β-cell cluster with GoF-K(ATP) channels. Our results indicate that in a heterogenous β-cell cluster with GoF-K(ATP) channels, there is an inverted u-shaped nonmonotonic relation between the cluster activity and Cx36 expression. These results show that in a neonatal diabetic β-cell model, gain of function mutations in the Kir6.1 cause Cx36 overexpression, which aggravates the impairment of glucose stimulated Ca2+ oscillations.</p

    Gain of function mutation in K(ATP) channels and resulting upregulation of coupling conductance are partners in crime in the impairment of Ca<sup>2+</sup> oscillations in pancreatic ß-cells

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    Gain of function mutations in the pore forming Kir6 subunits of the ATP sensitive K+ channels (K(ATP) channels) of pancreatic β-cells are the major cause of neonatal diabetes in humans. In this study, we show that in insulin secreting mouse β-cell lines, gain of function mutations in Kir6.1 result in a significant connexin36 (Cx36) overexpression, which form gap junctional connections and mediate electrical coupling between β-cells within pancreatic islets. Using computational modeling, we show that upregulation in Cx36 might play a functional role in the impairment of glucose stimulated Ca2+ oscillations in a cluster of β-cells with Kir6.1 gain of function mutations in their K(ATP) channels (GoF-K(ATP) channels). Our results show that without an increase in Cx36 expression, a gain of function mutation in Kir6.1 might not be sufficient to diminish glucose stimulated Ca2+ oscillations in a β-cell cluster. We also show that a reduced Cx36 expression, which leads to loss of coordination in a wild-type β-cell cluster, restores coordinated Ca2+ oscillations in a β-cell cluster with GoF-K(ATP) channels. Our results indicate that in a heterogenous β-cell cluster with GoF-K(ATP) channels, there is an inverted u-shaped nonmonotonic relation between the cluster activity and Cx36 expression. These results show that in a neonatal diabetic β-cell model, gain of function mutations in the Kir6.1 cause Cx36 overexpression, which aggravates the impairment of glucose stimulated Ca2+ oscillations.</p

    Geographical Features and Seroprevalence of Borrelia burgdorferi in Erzincan, Turkey

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    Background: We aimed to determine the geographical features and seroprevalence of Borrelia burgdorferi in Erzincan, Turkey, which has a high tick population due to its geographical position and climatic conditions. Methods: From January to December 2014, 368 people living in Erzincan, northeastern Turkey were enrolled. B. burgdorferi IgG antibodies were investigated in the collected serum samples using the ELISA method in 2015. Positive and borderline results were confirmed using the Western Blot (WB) method.  Results: Borrelia burgdorferi IgG positivity was found to be 4.1% by ELISA and 2.17% by WB. Of the seropositive people according to WB, 25% resided in areas within 2000m of rivers, 50% in areas with a slope of 0–5°, and 62.5% in areas with an altitude of lower than 1500 meters. Conclusion: The seroprevalence of Lyme borreliosis was high in Erzincan, particularly among people engaged in animal husbandry in rural areas. In addition, the seroprevalence of Borrelia varied according to geographical features, increasing in areas with a lower slope and altitude

    Assessment of sustained effects of levosimendan and dobutamine on left ventricular systolic functions by using novel tissue Doppler derived indices in patients with advanced heart failure

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    Background: Previous studies comparing levosimendan vs. dobutamine have revealed that levosimendan is better in relieving symptoms. Echocardiographic studies have been done using second measurements immediately following a dobutamine infusion or while it was still being administered. The aim of our study was assessment of sustained effects of 24 h levosimendan and dobutamine infusions on left ventricular systolic functions. Methods: A total of 61 patients with acutely decompensated heart failure with New York Heart Association (NYHA) class III or IV symptoms were randomized to receive either levosimendan or dobutamine 2:1 in an open label fashion. Before and 5 days after the initiation of infusions, functional class was assessed, N-terminal prohormone of B-type natriuretic peptide (NT-proBNP) levels and left ventricular ejection fraction (LVEF), mitral inflow peak E and A wave velocity, and E/A ratios were measured; using tissue Doppler imaging, isovolumic myocardial acceleration (IVA), peak myocardial velocity during isovolumic contraction (IVV), peak systolic velocity during ejection period (Sa), early (E’) and late (A’) diastolic velocities, and E’/A’ and E/E’ ratios were measured. Results: The NYHA class improved in both groups, but improvements were prominent in the levosimendan group. NT-proBNP levels were significantly reduced in the levosimendan group. Improvements in LVEF and diastolic indices were significant in the levosimendan group. Tissue Doppler-derived systolic indices of IVV and IVA increased significantly in the levosimendan group. Conclusions: Improvements in left ventricular systolic and diastolic functions continue after a levosimendan infusion.

    Patients with Black Hip and Black Knee Due to Ochronotic Arthropathy: Case Report and Review of Literature

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    Abstract Ochronotic arthropathy is a manifestation of longstanding alkaptonuria. With increasing age, an accumulation of pigment deposits of homogentisic acid in the joint cartilage results in ochronotic osteoarthritis. We present a case of a 62-year-old female who underwent staged left uncemented total hip and right cemented total knee arthroplasty for osteoarthritis secondary to ochronosis

    Patients with Black Hip and Black Knee Due to Ochronotic Arthropathy: Case Report and Review of Literature

    Get PDF
    Ochronotic arthropathy is a manifestation of longstanding alkaptonuria. With increasing age, an accumulation of pigment deposits of homogentisic acid in the joint cartilage results in ochronotic osteoarthritis. We present a case of a 62-year-old female who underwent staged left uncemented total hip and right cemented total knee arthroplasty for osteoarthritis secondary to ochronosis

    Antimicrobial resistance among migrants in Europe: a systematic review and meta-analysis

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    BACKGROUND: Rates of antimicrobial resistance (AMR) are rising globally and there is concern that increased migration is contributing to the burden of antibiotic resistance in Europe. However, the effect of migration on the burden of AMR in Europe has not yet been comprehensively examined. Therefore, we did a systematic review and meta-analysis to identify and synthesise data for AMR carriage or infection in migrants to Europe to examine differences in patterns of AMR across migrant groups and in different settings. METHODS: For this systematic review and meta-analysis, we searched MEDLINE, Embase, PubMed, and Scopus with no language restrictions from Jan 1, 2000, to Jan 18, 2017, for primary data from observational studies reporting antibacterial resistance in common bacterial pathogens among migrants to 21 European Union-15 and European Economic Area countries. To be eligible for inclusion, studies had to report data on carriage or infection with laboratory-confirmed antibiotic-resistant organisms in migrant populations. We extracted data from eligible studies and assessed quality using piloted, standardised forms. We did not examine drug resistance in tuberculosis and excluded articles solely reporting on this parameter. We also excluded articles in which migrant status was determined by ethnicity, country of birth of participants' parents, or was not defined, and articles in which data were not disaggregated by migrant status. Outcomes were carriage of or infection with antibiotic-resistant organisms. We used random-effects models to calculate the pooled prevalence of each outcome. The study protocol is registered with PROSPERO, number CRD42016043681. FINDINGS: We identified 2274 articles, of which 23 observational studies reporting on antibiotic resistance in 2319 migrants were included. The pooled prevalence of any AMR carriage or AMR infection in migrants was 25·4% (95% CI 19·1-31·8; I2 =98%), including meticillin-resistant Staphylococcus aureus (7·8%, 4·8-10·7; I2 =92%) and antibiotic-resistant Gram-negative bacteria (27·2%, 17·6-36·8; I2 =94%). The pooled prevalence of any AMR carriage or infection was higher in refugees and asylum seekers (33·0%, 18·3-47·6; I2 =98%) than in other migrant groups (6·6%, 1·8-11·3; I2 =92%). The pooled prevalence of antibiotic-resistant organisms was slightly higher in high-migrant community settings (33·1%, 11·1-55·1; I2 =96%) than in migrants in hospitals (24·3%, 16·1-32·6; I2 =98%). We did not find evidence of high rates of transmission of AMR from migrant to host populations. INTERPRETATION: Migrants are exposed to conditions favouring the emergence of drug resistance during transit and in host countries in Europe. Increased antibiotic resistance among refugees and asylum seekers and in high-migrant community settings (such as refugee camps and detention facilities) highlights the need for improved living conditions, access to health care, and initiatives to facilitate detection of and appropriate high-quality treatment for antibiotic-resistant infections during transit and in host countries. Protocols for the prevention and control of infection and for antibiotic surveillance need to be integrated in all aspects of health care, which should be accessible for all migrant groups, and should target determinants of AMR before, during, and after migration. FUNDING: UK National Institute for Health Research Imperial Biomedical Research Centre, Imperial College Healthcare Charity, the Wellcome Trust, and UK National Institute for Health Research Health Protection Research Unit in Healthcare-associated Infections and Antimictobial Resistance at Imperial College London
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