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Silicon nanowire field-effect transistors are promising devices used to detect minute amounts of different biological species. We introduce the theoretical and computational aspects of forward and backward modeling of biosensitive sensors. Firstly, we introduce a forward system of partial differential equations to model the electrical behavior, and secondly, a backward Bayesian Markov-chain Monte-Carlo method is used to identify the unknown parameters such as the concentration of target molecules. Furthermore, we introduce a machine learning algorithm according to multilayer feed-forward neural networks. The trained model makes it possible to predict the sensor behavior based on the given parameters.
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Nanofios , Redes Neurais de Computação , Algoritmos , Teorema de Bayes , Método de Monte CarloRESUMO
BACKGROUND: Skin prick test (SPT) has the best positive predictive value to diagnose respiratory atopic diseases, including allergic rhinitis (AR), but the association of severity of allergic symptom and SPT reaction size has not been clearly determined yet. METHODS: In this a cross- sectional investigation, the severity of disease is classified using a visual analog scale for main symptoms, and SPT was conducted according to the principles of the European Academy of Allergy and Clinical Immunology. RESULTS: Thirty seven percent of the participants had at least one severe symptom. Patients with sensitivity to Alternaria (common allergens in humans) or tree pollens had more severe symptoms. We found that in patients who had sensitivity to Russian thistle pollen, wheal size >6 mm, was associated with more severe symptoms. CONCLUSION: Despite previous conflicts to rely on SPT test for starting immunotherapy, we recommend this test especially for patients sensitive to Alternaria, weed pollens, and tree pollens, considering the size of wheal in association with AR symptom severity.
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Rinite Alérgica , Urticária , Alérgenos , Humanos , Pólen/imunologia , Rinite Alérgica/diagnóstico , Rinite Alérgica/epidemiologia , Índice de Gravidade de Doença , Testes Cutâneos , Urticária/diagnósticoRESUMO
INTRODUCTION AND IMPORTANCE: Phrenic nerve schwannoma is an occasional axonal tumor that is mostly asymptomatic. CASE PRESENTATION: In this report, a man with a painless lump in his neck was the subject. His diagnostic process included the recording of schwannoma. Phrenic schwannoma was removed by surgery without any complication during follow-up. CLINICAL DISCUSSION: Surgical excision under general anesthesia was done for the patient and during the surgical explore, the surgeon observed that, the schwannoma arose from the cervical phrenic nerve. The cervical mass was dissected from the phrenic nerve precisely by intracapsular enucleation technique. CONCLUSION: The phrenic involvements of schwannomas are extremely rare and mostly presented as a painless mass. Additionally, complete surgical excision of them is an efficient method.
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Background: Oxidative stress due to iron accumulation in patients with beta-thalassemia major (BTM) causes complications such as tissue damage and destruction. This study aimed to assess the association between the serum prooxidant/antioxidant balance (PAB) and blood parameters in patients with BTM. Methods: This cross-sectional study included 92 patients with BTM. In this study, PAB was measured using an enzyme-linked immunosorbent assay (ELISA). Serum ferritin, blood urea nitrogen (BUN), creatinine (Cr), alanine aminotransferase (ALT), aspartate aminotransferase (AST), thyroid-stimulating hormone (TSH), total cholesterol (TC), triglyceride (TG), complete blood cell count (CBC), and history of blood transfusion were recorded. The association of the blood parameters was assessed across the tertiles (T) of serum PAB (highest T vs. lowest T). Results: The results showed that high serum ferritin was directly associated with serum PAB [odds ratio (OR), 12.80; 95% confidence interval (CI), 2.98â54.91; T3 vs. T1]. Also, direct associations were found for high TC (OR, 4.97; 95% CI, 1.42â17.32; T3 vs. T1), high ALT (OR, 4.95; 95% CI, 1.33â18.46; T3 vs. T1) and high TSH (OR, 3.78; 95% CI, 1.10â13.02; T3 vs. T1). Conclusion: The findings of the present study showed that serum PAB levels were directly associated with ferritin, ALT, TC, and TSH levels. This indicates that improvements in blood parameters, especially ferritin and TSH levels, occur by ameliorating oxidative stress in patients with BTM.
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A patient presented with edema, ascites and jaundice. Histologic report was consistent with Celiac Disease. Liver biopsy commensurate with Glycogen storage disease III, which was confirmed by genetic testing. A gluten-free diet was initiated. After 2 months, ascites was relieved, hepatic function was improved, and hepatic size reduced.
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Background: We aimed to elucidate the pathogenic bacterial and fungal profiles of specimens obtained from suspected ocular infections at Farabi Eye Tertiary Referral Hospital, Tehran, Iran. Methods: In this cross-sectional study, we collected data from ocular specimens taken during the seven-year period of 2011 to 2018, and the results were then retrospectively analyzed. Samples had been obtained from patients who were investigated for ocular infections. Results: Overall, 16,656 ocular samples were evaluated. The mean patient age was 48.31 ± 26.62 years. Most patients were men (60.33%), and men in the 7th decade of life were the largest represented group. The seasonal distributions of specimen collection sites followed the overall distribution of collection sites by year. Specimens obtained from the cornea were the most common (49.24%), also representing the largest number of specimens in all seasons. The most commonly isolated fungal microorganisms were Fusarium spp., followed by Aspergillus spp. and Candida albicans. Of the 6,556 specimens with positive bacterial cultures, 59% produced gram-positive bacteria, while the remainder produced gram-negative pathogens. The most commonly isolated bacteria were Pseudomonas aeruginosa (17.77%), Staphylococcus epidermidis (13.80%), Streptococcus pneumoniae (13.27%), S. viridans (12.23%), and S. aureus (11.18%). Conclusion: Most submitted specimens were obtained from the cornea. The most commonly isolated fungal microorganisms were Fusarium spp., followed by Aspergillus spp. and C. albicans. The most commonly isolated bacteria were P. aeruginosa, followed by S. epidermidis and S. pneumoniae.
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Methylenetetrahydrofolate reductase (MTHFR) polymorphism may play an important role in the pathophysiology of obesity and diabetes accompanied by obesity due to its influence on plasma homocysteine levels. There are significant and sometimes very strong relationship between levels of homocysteine and several multi-system diseases including CHD and CVA. To examine the association between MTHFR gene C677T polymorphism in diabetes and obesity with serum homocysteine levels. A total of 682 subjects were recruited in four groups (Normal, obese, diabetic and obese and diabetics). MTHFR gene C677T polymorphism was detected using PCR-RFLP technique. Serum homocysteine levels were measured using HPLC. There was a significant increase in the mean serum homocysteine levels in subjects carrying TT genotype (34.6 +/- 26.5) compared to subjects carrying CC (15.1 +/- 8) or CT genotype (16.4 +/- 7.8) (P < 0.000). We found no significant differences for MTHFR allele and genotype frequencies between different groups. Our data have confirmed the association between serum homocysteine levels and MTHFR C677T genotype reported in other populations.
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Complicações do Diabetes/enzimologia , Complicações do Diabetes/genética , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Obesidade/complicações , Obesidade/genética , Polimorfismo de Nucleotídeo Único/genética , Adulto , Alelos , Complicações do Diabetes/sangue , Feminino , Frequência do Gene/genética , Homocisteína/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/sangue , Obesidade/enzimologiaRESUMO
Coronavirus disease 2019 or COVID-19 has rapidly emerged as a global pandemic. This viral infection involves the upper respiratory tract and could lead to severe pneumonia with respiratory distress or even death. Certain studies have found higher initial plasma levels of most pro-inflammatory cytokines during the course of the infection. In this context, both in vitro and in vivo studies have revealed that metronidazole could decrease the levels of several cytokines, which are known to increase during the COVID-19 infection, including interleukin (IL)8, IL6, IL1B, tumor necrosis factor (TNF)α, IL12, IL1α, and interferon (IFN)γ, as well as the levels of C-reactive protein (CRP) and neutrophil count. Furthermore, the drug could decrease neutrophil-generated reactive oxygen species during inflammation. Metronidazole could counteract majority of the immunopathological manifestations of the COVID-19 infection. Therefore, studies with a large sample size are required to determine the efficacy of metronidazole in the treatment of COVID-19 infection.
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In this work, we propose a parameter estimation framework for fracture propagation problems. The fracture problem is described by a phase-field method. Parameter estimation is realized with a Bayesian approach. Here, the focus is on uncertainties arising in the solid material parameters and the critical energy release rate. A reference value (obtained on a sufficiently refined mesh) as the replacement of measurement data will be chosen, and their posterior distribution is obtained. Due to time- and mesh dependencies of the problem, the computational costs can be high. Using Bayesian inversion, we solve the problem on a relatively coarse mesh and fit the parameters. In several numerical examples our proposed framework is substantiated and the obtained load-displacement curves, that are usually the target functions, are matched with the reference values.
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The zoonotic Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and its resultant human coronavirus disease (COVID-19) recently appeared as a global health threat that can cause severe respiratory infection and terminal respiratory distress. By the first week of April, more than 1.3 million people had been globally infected and more than 70,000 had lost their lives to this contagious virus. Clinical manifestations occur shortly after exposure, or a few days later. There is controversy regarding the transmission of the virus through the tear and conjunctiva; however, there are reports that the ocular surface might be a potential target for COVID-19. The ease of transmission of this virus at close proximity presents a risk to eyecare workers. Several recommendations have been issued by local and national organizations to address the issue of safe ophthalmic practice during the ongoing COVID-19 pandemic. These guidelines have numerous similarities; however, subtle differences exist. The purpose of this paper was to discuss measures, with a specific focus on standard precautions, to prevent further dissemination of COVID-19 at Eye Clinics. We have proposed procedures to triage suspected cases of COVID-19, considering emergency conditions.
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BACKGROUND: We aimed to use the scientometric approach to evaluate immunological studies on the subject of sulfur mustard over the past 20 years. METHODS: In this scientometric study, the Web of Science Core Collection was searched on the studies about sulfur mustard. The published papers related to the field of immunology were retrieved from these papers. HistCite software and VOSviewer were the applied software packages for bibliometric analysis, information visualization, and creating bibliometric networks. RESULTS: Over the past 20 years, 741 researchers from 22 countries have published 201 scientific papers in 95 journals. Iran and the United States with 93 and 68 published articles ranked at the top. The Journal of International Immunopharmacology, with 33 published papers, 439 Total Global Citation Score (TGCS), and 105 Total Local Citation Score (TLCS) was the most productive and most influential in this regard. The paper entitled "Biomonitoring of exposure to chemical warfare agents: A review" and another paper entitled "Sardasht-Iran Cohort Study of Chemical Warfare Victims: Design and Methods" were the most influential papers in this topic with 200 TGCS and 27 TLCS, respectively. The most productive and the most influential centers were "Immunoregulation Research Center of Shahed University" and "The Janbazan Medical and Engineering Research Center (JMERC)," respectively. CONCLUSION: The result of our report as the unique scientometric evaluation of the research on sulfur mustard and Immunology can be used as a roadmap for authors, researchers, and policymakers to define the best ways to allocate their financial and executive resources.
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In this paper, we employ the multilevel Monte Carlo finite element method to solve the stochastic Cahn-Hilliard-Cook equation. The Ciarlet-Raviart mixed finite element method is applied to solve the fourth-order equation. In order to estimate the mild solution, we use finite elements for space discretization and the semi-implicit Euler-Maruyama method in time. For the stochastic scheme, we use the multilevel method to decrease the computational cost (compared to the Monte Carlo method). We implement the method to solve three specific numerical examples (both two- and three dimensional) and study the effect of different noise measures.
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The aim of this study was to describe patient demographics, microbiological profile, and antibiotic susceptibility of corneal ulcer at a tertiary referral center to improve and optimize diagnosis and treatment of this potentially blinding entity and to reduce antibiotic misuse. Detailed external and slit-lamp bio-microscopic examination of 123 consecutive patients with suspected corneal ulcer was performed at an ophthalmology clinic. Corneal scraping was carried out under slit-lamp bio-microscopy. The obtained material was inoculated on culture media and smeared on a slide for Gram's staining for morphological identification of bacteria and fungus. For samples that developed colony in culture media, antibiotic susceptibility testing was performed. In a significant percentage of patients (72%) neither bacterial agents nor fungi were the cause of corneal ulcer. Of the 34 culture-proven corneal ulcers, in 79% of the cases, bacteria were detected while in 21% of cases, fungi were found. Of the 27 bacterial corneal ulcers, the majority were (67%) caused by Gram-positive bacteria, of which 50% were Streptococcus pneumoniae, and in the Gram-negative bacterial corneal ulcers, most of the cases (44%) were caused by Pseudomonas aeruginosa. In the antibiotic susceptibility report, Streptococcus pneumoniae, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli were resistant to Cotrimoxazole (TS), Streptococcus pneumoniae to Erythromycin (E), Staphylococcus aureus to Peniciline (PG), Pseudomonas aeruginosa to Ceftriaxone (CRO) and Nitrofurantoin (NI), and finally, Escherichia coli to Gentamicin (GM). In conclusion, in a significant number of the patients neither bacterial agents nor fungi were offending microorganisms and bacteria were the most common agent of microbiological corneal ulcer, found in 79% of culture-proven corneal ulcers, followed by fungus, found in 21% of culture-proven corneal ulcers.
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BACKGROUND: Association of Selenium (Se) deficiency, an essential trace element, has been found with human diseases. Identifying literature trends on the effects of Se on the thyroid may guide in planning future studies. METHODS: A literature search was conducted using the Web of Science database to identify studies on Se and the thyroid published over the 20 years duration (1995-Dec 2014). Scientometric indices were used to draw field maps. The scientific processes, structure, evidence history, and international collaborations were included in the map. The most influential authors, journals, institutions, and countries were also examined. RESULTS: Our search identified 184 research and review papers. The number of scientific studies on Se and the thyroid has been irregular, but interest in this topic has increased in recent years. The highest number of studies was published in 2014 (16 papers) and overall growth factor of publication was 3.78. Overall, 744 authors from 282 institutions in 43 countries published in this field. The author J. Kohrle (828 citations, 14 publications), and German scientists (1272 citations, 30 publications) were most influential. CONCLUSION: This study reveals the interrelationships between different publications on the effects of Se on the thyroid. Leading scientific issues and their extent of impact were successfully determined by examining citations. The results of systematic citations and mapping fields can be used to assist in policy and management contexts.