55 research outputs found
Time-Gated Luminescent In Situ Hybridization (LISH): Highly Sensitive Detection of Pathogenic Staphylococcus aureus
No full textWe describe simple direct conjugation of a single TEGylated Europium chelate to DNA that binds to intracellular rRNA and is then detected using a homogeneous luminescent in situ hybridisation (LISH) technique. As a proof-of-principle, Staphylococcus aureus (S. aureus) was selected as a model for our study to show the ability of this probe to bind to intracellular 16S ribosomal rRNA. A highly purified Europium chelate conjugated oligonucleotide probe complementary to an rRNA sequence-specific S. aureus was prepared and found to be soluble and stable in aqueous solution. The probe was able to bind specifically to S. aureus via in situ hybridisation to differentiate S. aureus from a closely related but less pathogenic Staphylococcus species (S. epidermidis). A time-gated luminescent (TGL) microscope system was used to generate the high signal-to-noise ratio (SNR) images of the S. aureus. After excitation (365 nm, Chelate λmax = 335 nm), the long-lived (Eu3+) luminescent emission from the probe was detected without interference from natural background autofluorescence typically seen in biological samples. The luminescent images were found to have 6 times higher SNR or sensitivity compared to the fluorescent images using conventional fluorophore Alexa Fluor 488. The TEGylated Europium chelate -oligo probe stained S. aureus with mean signal intensity 3.5 times higher than the threshold level of signal from S. epidermidis (with SNR 8 times higher). A positive control probe (EUB338–BHHTEGST–Eu3+) has mean signal intensity for S. aureus and S. epidermidis equally 3.2 times higher than the threshold of signal for a negative NON-EUB338 control probe. The direct conjugation of a single Europium chelate to DNA provides simplicity and improvement over existing bovine serum albumin (BSA)/streptavidin/biotinylated DNA platforms for multi-attachment of Europium chelate per DNA and more importantly makes it feasible for hybridisation to intracellular RNA targets. This probe has great potential for highly sensitive homogeneous in situ hybridisation detection of the vast range of intracellular DNA targets
Sirvan Sayyad, An Epidemiological Survey of Head Louse Infestation Among Primary School children in Rural Areas of Ravansar County, West of Iran
No full textAbstract: Head louse (Pediculus humanus capitis) is an obligate wingless insect that transmitted from a person to another, thorough physical contacts. Pediculusis is a health problem that is affect schoolchildren especially in poor countries. The present study was conducted to evaluate the prevalence rate of pediculosis among primary schoolchildren and its associated factors in rural areas of Ravansar County. The sample size was 385 girl students in 6 villages, including Quri Qaleh, Boz gureh, Qeshlaq, Mansur-e Aqai, Shahrak-e Serias and Tazehabad-e Serias. A questionnaire that included questions relating to the following: age, school grade, socio-economic status, parent's job, level of parents' education and family size was used. Data were analyzed by SPSS software with proper statistical test. 61 (15.8%) of the examined students were infested to head louse. The most prevalent infestation was observed in 8-9 year-old students and the lowest infestation were reported in students of ≥12 years old. There was a significant statistical relationship between head louse infestation and some related factors such as mother's education, frequency of hair washing, using common comb (p<0.05). The results of the present survey and many studies in Iran and foreign countries show that head louse infestation is a cosmopolitan health problem with different prevalence rates regionally but it remains as a considerable pediatric problem
The Evaluation of Ontology Matching versus Text
No full textLately, the ontologies have become more and more complex, and they are used in different domains. Some of the ontologies are domain independent; some are specific to a domain. In the case of text processing and information retrieval, it is important to identify the corresponding ontology to a specific text. If the ontology is of a great scale, only a part of it may be reflected in the natural language text. This article presents metrics which evaluate the degree in which an ontology matches a natural language text, from word counting metrics to text entailment based metrics.Ontology, Natural Language Processing, Metric
Immunogenicity of COVID-19 mRNA vaccines in hemodialysis patients: Systematic review and meta-analysis
No full textBackground and Aims Vaccine response is a concern in hemodialysis patients. Given that hemodialysis patients were not included in clinical trials, we aimed to synthesize the available evidence on the immunogenicity of coronavirus disease 2019 (COVID-19) mRNA vaccines in hemodialysis patients. Methods We searched Scopus, PubMed, Sciencedirect, and finally google scholar databases for studies on COVID-19 mRNA-vaccines immunogenicity in hemodialysis patients up to December 1, 2021. Eligible articles measured antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spike or Receptor-Binding Domain Antibody (S/RBD) postimmunization with COVID-19 mRNA vaccines. The immunogenicity of the vaccine was evaluated using seroconversion rates measured between 21 and 30 days after the first immunization and between 14 and 36 days post the second dose. We included studies including participants without a history of COVID-19 before vaccination. Healthy controls or health-care workers served as the control groups. After selecting eligible articles, the data were finally extracted from included articles. We used a random effects model to estimate the pooled seroconversion rate after COVID-19 mRNA vaccine administration. We assessed the heterogeneity between studies with the I-2 statistical index. Result We selected 39 eligible citations comprising 806 cases and 336 controls for the first dose and 6314 cases and 927 controls for the second dose for statistical analysis. After the first dose of mRNA vaccines, the seroconversion rate was 36 (95 confidence interval CI: 0.24-0.47) and 68% (95% CI: 0.45-0.91) in hemodialysis patients and the control group, respectively. While seroconversion rate after the second dose of mRNA vaccines was 86% (95% CI: 0.81-0.91) and 100% (95% CI: 1.00-1.00) in hemodialysis patients and the control group, respectively. Conclusion Although the immune response of hemodialysis patients to the second dose of the SARS-CoV-2 mRNA vaccine is very promising, the seroconversion rate of dialysis patients is lower than healthy controls. Periodically assessment of antibody levels of hemodialysis patients at short intervals is recommended
The prevalence of human bocavirus in <2-year-old children with acute bronchiolitis
No full textAcute bronchiolitis is one of the most common lower respiratory tract infections in children with less than 2 years of age. Nowadays, molecular methods provide an opportunity to better understand the etiology of bronchiolitis. Several viral agents including Respiratory syncytial virus (RSV), Rhinovirus, Parainfluenza and Human bocavirus (HBoV) are responsible for acute bronchiolitis. There are growing studies on the prevalence of HBoV in patients with bronchiolitis. The present systematic review and meta-analysis were conducted to determine the pooled prevalence of HBoV in the respiratory samples of children with acute bronchiolitis. A literature search was conducted in the databases of PubMed, Scopus and Web of Science to recruit studies reporting the frequency of HBoV in <2-year-old children with acute bronchiolitis from 2005 to 2019. Only studies that used polymerase chain reaction (PCR)-based methods to detect the virus in nasopharyngeal samples were included. A total of 22 studies assessing 6751 cases were analyzed. According to the meta-analysis based on the random-effects model, the overall prevalence of HBoV in children with <2 years old was obtained 13 (95 CI: 0.09-0.17). Additionally, the rates of single (as the sole organism) and mixed (in combination with other viruses) HBoV infections were 4 and 9, respectively. This study showed a high rate of HBoV detection in children with acute bronchiolitis. This should be considered as part of a diagnostic test panel for respiratory infections in children with bronchiolitis. © 2020 The Author
Lipopolysaccharide and Morphine-3-Glucuronide-Induced Immune Signalling Increases the Expression of Polysialic Acid in PC12 Cells
No full text© 2019, Springer Science+Business Media, LLC, part of Springer Nature. Polysialic acid (polySia), a long homopolymer of 2,8-linked sialic acids, is abundant in the embryonic brain and is restricted largely in adult brain to regions that exhibit neurogenesis and structural plasticity. In the central nervous system (CNS), polySia is highly important for cell-cell interactions, differentiation, migration and cytokine responses, which are critical neuronal functions regulating intercellular interactions that underlie immune signalling in the CNS. In recent reports, a metabolite of morphine, morphine-3-glucuronide (M3G), has been shown to cause immune signalling in the CNS. In this study, we compared the effects of neurite growth factor (NGF), lipopolysaccharide (LPS) and M3G exposure on the expression of polySia in PC12 cells using immunocytochemistry and Western blot analysis. PolySia was also extracted from stimulated cell proteins by endo-neuraminidase digestion and quantitated using fluorescent labelling followed by HPLC analysis. PolySia expression was significantly increased following NGF, M3G or LPS stimulation when compared with unstimulated cells or cells exposed to the TLR4 antagonist LPS-RS. Additionally, we analyzed the effects of test agent exposure on cell migration and the oxidative stress response of these cells in the presence and absence of polySia expression on their cell surface. We observed an increase in oxidative stress in cells without polySia as well as following M3G or LPS stimulation. Our study provides evidence that polySia expression in neuronal-like PC12 cells is influenced by M3G and LPS exposure alike, suggestive of a role of TLR4 in triggering these events
Contribution value of akt, c-myc, cip2a, and pp2a genes expression in leukemogenesis: A bright perspective on the molecular pattern of patients with acute myeloid leukemia (aml)
No full textBackground: The heterogeneous nature of acute myeloid leukemia (AML) and the hurdle to find a suitable treatment strategy for this malignancy put this type of leukemia at the top of the list of the priorities for finding a valuable biomarker to improve its treatment and predict the outcome of the patients. Objectives: Given the involvement of the variety of signaling pathways, foremost the PI3K axis in the pathogenesis of human can-cers, we aimed to investigate the expression of the most important downstream targets of this pathway to propose a plausible mechanism underlying AML pathogenesis. Methods: In this case-control study, the blood samples from 30 patients diagnosed with AML were collected and after extracting their RNAs, the expression levels of Akt, c-Myc, CIP2A, and PP2A were evaluated using qRT-PCR analysis. For the control group, we also collected blood samples from 10 healthy volunteers. Afterward, by applying statistical analysis, we determined the probable correlation between the expressions of the aforementioned genes. Results: There was a significant elevation in the expression levels of Akt, c-Myc, and CIP2A coupled with the meaningful reduction in the expression level of PP2A in AML samples. However, we failed to find any significant association between the expression level of the indicated genes and age, sex, and the percentage of the blasts. Conclusions: As the most straightforward interpretation of our results, we propose that probably the association between PI3K and c-Myc which is built through the interaction between CIP2A and PP2A may play a pivotal role in the pathogenies of AML and any component of this axis could serve as a potential new target for more profound treatment strategy. However, further detailed inves-tigations in this field are required to clarify the exact role of this interesting testis-specific pathway in the context of hematological malignancies, in particular AML. © 2020, Author(s)
Effect of Bed Roughness and Negative Step on Characteristics of Hydraulic Jump in Rectangular Stilling Basin
No full textWater flow often releases excess energy after passing through gates and spillways. This energy should be reduced to avoid the destruction of downstream structures. The hydraulic jump, a natural phenomenon, inevitably reduces incoming flow energy. The experiments were carried out in this study to investigate the effect of bed roughness and abrupt negative drops on the characteristics of the hydraulic jump. Also, to investigate the effect of geometric and hydraulic parameters on energy dissipation and location of the hydraulic jump, there was a change in the height of the abrupt drop and roughness for different discharges between 30 and 50 L/s and the Froude numbers were ranging from 4.9 to 9.5. The results showed that increasing the bed roughness causes a reduction of the sequent depth ratio and the relative length of the jump by 16.6% and 20.7%, respectively, and increases the relative energy loss and the bed shear force coefficient by 10% and 31%, respectively. In contrast, increasing the step height causes an increase in the sequent depth ratio and the relative length of the jump by 6.5% and 7%, respectively, and increases the relative energy loss and the bed shear force coefficient by 11% and 3.2%, respectively
DEVELOPMENT OF THE SUSTAINABLE ENTREPRENEURSHIP MODEL
No full textThe most prominent feature of today’s economy is rapid change. To succeed in such an economy, countries must be able to adapt to these changes with great agility. One of the most potent tools for achieving this end is sustainable entrepreneurship. Sustainable entrepreneurs are those who undertake entrepreneurial endeavors while taking into account different aspects of social, economic and environmental sustainability. These entrepreneurs strive to keep their resources focused on sustainable development and to balance the objectives of entrepreneurial success and sustainability so as to solve social and environmental problems. In this study, after reviewing the research literature and identifying the factors pertinent to sustainable entrepreneurship, a conceptual model was developed by drawing on the expertise of 10 experts, who were selected by snowball sampling. Interpretive Structural Modeling (ISM) approach was used to examine the network of relationships among the factors. The findings showed that the considered factors fall into four levels: sustainability culture was placed at the most fundamental level, legal requirements, resource preservation, social participation, green management and human resources management were placed at the second level, social justice, effective and efficient processes, and customer-centricity were placed at the third level, and social well-being and economic benefits were identified as the top-level factors or outputs of sustainable entrepreneurship. The proposed model depicted means, process, first order and ultimate goal in inhacing entrepreneurship sustainability endeavors
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