Using space syntax method to train a model for unsupervised detection of socio-economic conditions - the case of metropolitan area of Tehran

The availability of open-source data, coupled with recent advances in technology has made it easier to create large scale urban and regional models used in the field of environmental studies and specifically space syntax. With the use of open data, large scale regional road-centre line models (Turner, 2005) can now be created and processed to explain the spatial configuration as well as the structure of the built environment. While the study of the socio-economic condition of the built environment correlated with the configuration of the space has been the general use of these models, there has been less focus on multi-layered analysis and metrics across a large model. On another hand, with restrictions on datasets from formal resources, the conventional use of space syntax theories and methods are limited. However, incorporating more advanced methods of quantitative analysis, space syntax can compensate for the lack of available formal dataset in reading and/or predicting environmental phenomena. Given that with the available data sources such as Open Street Map, consistent spatial network models are available, RCL segment models can be trained to predict the socio-economic condition of areas where the formal data is not obtainable. This research puts forward a workflow through which, the spatial network model can be used to train a model that predicts mentioned phenomena. This workflow uses a large segment model of the metropolitan area of Tehran and uses the centrality measures from space syntax analysis to train an unsupervised model which can predict possible missing information. It also assesses the efficacy of the model and shows to what extent the model is to be trusted and what the shortcomings of the model are. It is shown that although the models are very efficient in predicting the required conditions there should be a supervised assessment on the parameters of the algorithms to optimize the outcome

Correlation between hepatitis B G1896A precore mutations and HBeAg in chronic HBV patients

Background: Hepatitis B virus (HBV) infection is an important health concern worldwide, with critical outcomes. Hepatitis B e antigen (HBeAg) negative chronic hepatitis B is frequently caused by a mutation (G1896A) in the hepatitis B virus (HBV) precore (PC) reading frame, which creates a stop codon, causing premature termination of the HBe protein. Objectives: This study aimed to investigate the G1896A PC mutation and its effect on HBeAg detection in chronic HBV patients. Patients and Methods: In this study, 120 chronic HBV patients neither vaccinated or who had benefited from immunoglobulin therapy, were recruited. The HBV-DNA was extracted from plasma and polymerase chain reaction (PCR) was performed. Positive PCR products were subjected to automated sequencing. The HBV serological markers hepatitis B s antigen (HBsAg), HBeAg were tested. Results: One hundred out of 120 (83.3%) patients were HBeAg negative and 100% were HBsAg positive. The comparison of nucleotide sequences with the reference sequence (Accession number: AB033559) in HBeAg negative patients showed that there was a high rate of mutations in G1896A (93.18%). Conclusions: This study indicates that the rate of G1896A mutation at the PC region among HBeAg negative patients, in the Golestan province of Iran, was similar to the average rate encountered in other parts of Iran. The PC stop codon mutation was detected in 93.18% of HBeAg negative patients. Further studies with larger sample sizes are required to elucidate the exact role of these mutations in the clinical course of chronic HBV infection. © 2015, Ahvaz Jundishapur University of Medical Sciences

Mutations in pre-core and basal-core promoter regions of hepatitis B virus in chronic HBV patients from Golestan, Iran

Objective(s): It has been reported that the mutation of the pre-core (PC) and basal-core promoter (BCP) may play an important role in the development of HBV-related hepatocellular carcinoma (HCC). In this study the PC and BCP mutations were investigated in chronic HBV patients. Materials and Methods: In this study, 120 chronic HBV patients from Golestan, Northeast of Iran who were not vaccinated against HBV, were recruited from the year 2008 to 2012. HBV-DNA extraction from plasma and PCR were performed and positive PCR products were subjected to automated sequencing. Results: One hundred out of 120 (83.3%) patients were HBeAg negative. Comparison of our nucleotide sequences with reference sequence showed high rate mutation in BCP and PC region (96.66%). Frame shift mutation was found in 78 (65%) of patients in BCP region, among them 8 (6.6%) patients showed mutation in PC region. Conclusion: Our results demonstrated high rate of mutations in BCP and PC regions among HBV chronic patients in Northeast of Iran

Mutations in the S gene region of hepatitis B virus genotype D in Golestan Province-Iran

Mutations of HBsAg especially within the "a" determinant could alter the antigenicity of the protein causing failure of HBsAg neutralization and escaping from the host's immune system, resulting in active viral replication and liver disease. This project aimed to investigate mutation in the S gene region of HBV infected patients in Golestan Province-Iran. HBV-DNA extractions from plasma and PCR of 100 patients were performed. Direct sequencing and alignment of S gene were applied using reference sequence from Gene Bank database. All isolates were belonged to genotype D, subgenotype D1, subtype ayw2. Overall 92 point mutations occurred. Of them, 40 (43.47%) were missense and 52 (56.52%) were silent. Mutations were detected in 95 cases (95%). Five of 40 mutations (12.5%) occurred in "a" determinant and 13 (32.5%), 17 (42.5%), and 2 (5%) were seen in antigenic epitope regions of B cell, CD4⁺ and CTL, respectively. Frame shift mutations were seen in 22 cases (22%). 14% of mutations occurred at Major Hydrophilic Region(MHR) area which P120T/S and R122K/T substitutions were the most frequent ones (4%). Mutation in G145R of the S gene was observed in one case. A large number of MHR mutants are in association with failure of HBsAg detection, vaccine, and immunotherapy escape. This study showed "a" determinant S gene mutations in HBV infected people with HBsAg positivity in Golestan Province-Iran. The rate of mutation in our study was 95%. Collectively, the results of this project exhibited that most of mutations were clustered in CD4⁺ antigenic epitopes. © Springer Science+Business Media, LLC 2012

Oral poliovirus vaccine-induced programmed cell death involves both intrinsic and extrinsic pathways in human colorectal cancer cells.

PURPOSE: Colorectal cancer (CRC) is one of the most common causes of cancer death throughout the world. Replication-competent viruses, which are naturally able to infect and lyse tumor cells, seem to be promising in this field. The aim of this study was to evaluate the potential of oral poliovirus vaccine (OPV) on human CRC cells and elucidate the mechanism of apoptosis induction. MATERIALS AND METHODS: Protein and gene expression of poliovirus (PV) receptor (CD155) on four human CRC cell lines including HCT116, SW480, HT-29, and Caco-2 and normal fetal human colon (FHC) cell line as a control were examined by flow cytometry and SYBR Green Real-Time PCR, respectively. Cytotoxicity of OPV on indicated cell lines was tested using MTT assay. The ability of OPV on apoptosis induction for both intrinsic and extrinsic pathways was examined using caspase-8 and caspase-9 colorimetric assay kits. The PV propagation in mentioned cell lines was investigated, and the quantity of viral yields (cells associated and extracellular) was determined using TaqMan PCR. RESULTS: CD155 mRNA and protein were expressed significantly higher in studied CRC cell lines rather than the normal cell line (P=0). OPV induced cell death in a time- and dose-dependent manner in human CRC cells. Apoptosis through both extrinsic and intrinsic pathways was detected in CRC cells with the minimum level found in FHC. PV viral load was significantly correlated with apoptosis via extrinsic (R=0.945, P=0.0001) and intrinsic (R=0.756, P=0.001) pathways. CONCLUSION: This study suggests that OPV has potential for clinical treatment of CRC. However further studies in animal models (tumor xenografts) are needed to be certain that it is qualified enough for treatment of CRC

Point of Care Diagnostics in the Age of COVID-19.

The recent outbreak of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its associated serious respiratory disease, coronavirus disease 2019 (COVID-19), poses a major threat to global public health. Owing to the lack of vaccine and effective treatments, many countries have been overwhelmed with an exponential spread of the virus and surge in the number of confirmed COVID-19 cases. Current standard diagnostic methods are inadequate for widespread testing as they suffer from prolonged turn-around times (>12 h) and mostly rely on high-biosafety-level laboratories and well-trained technicians. Point-of-care (POC) tests have the potential to vastly improve healthcare in several ways, ranging from enabling earlier detection and easier monitoring of disease to reaching remote populations. In recent years, the field of POC diagnostics has improved markedly with the advent of micro- and nanotechnologies. Due to the COVID-19 pandemic, POC technologies have been rapidly innovated to address key limitations faced in existing standard diagnostic methods. This review summarizes and compares the latest available POC immunoassay, nucleic acid-based and clustered regularly interspaced short palindromic repeats- (CRISPR)-mediated tests for SARS-CoV-2 detection that we anticipate aiding healthcare facilities to control virus infection and prevent subsequent spread

COVID-19: The Immune Responses and Clinical Therapy Candidates.

The pandemic of coronavirus disease 2019 (COVID-19), with rising numbers of patients worldwide, presents an urgent need for effective treatments. To date, there are no therapies or vaccines that are proven to be effective against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Several potential candidates or repurposed drugs are under investigation, including drugs that inhibit SARS-CoV-2 replication and block infection. The most promising therapy to date is remdesivir, which is US Food and Drug Administration (FDA) approved for emergency use in adults and children hospitalized with severe suspected or laboratory-confirmed COVID-19. Herein we summarize the general features of SARS-CoV-2's molecular and immune pathogenesis and discuss available pharmacological strategies, based on our present understanding of SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV) infections. Finally, we outline clinical trials currently in progress to investigate the efficacy of potential therapies for COVID-19

Metal-Organic Framework-Enhanced ELISA Platform for Ultrasensitive Detection of PD-L1

© 2020 American Chemical Society. The programmed cell death ligand 1 (PD-L1) protein has emerged as a predictive cancer biomarker and sensitivity to immune checkpoint blockade-based cancer immunotherapies. Current technologies for the detection of protein-based biomarkers, including the enzyme-linked immunosorbent assay (ELISA), have limitations such as low sensitivity and limit of detection (LOD) in addition to degradation of antibodies in exposure to environmental changes such as temperature and pH. To address these issues, we have proposed a metal-organic framework (MOF)-based ELISA for the detection of the PD-L1. A protective coating based on Zeolitic Imidazolate Framework 8 (ZIF-8) MOF thin film and polydopamine-polyethylenimine (PDA-PEI) was introduced on an ELISA plate for the improvement of antibody immobilization. Sensitivity and LOD of the resulting platform were compared with a conventional ELISA kit, and the bioactivity of the antibody in the proposed immunoassay was investigated in response to various pH and temperature values. The LOD and sensitivity of the MOF-based PD-L1 ELISA were 225 and 15.12 times higher, respectively, compared with those of the commercial ELISA kit. The antibody@ZIF-8/PDA-PEI was stable up to 55 °C and the pH range 5-10. The proposed platform can provide sensitive detection for target proteins, in addition to being resistant to elevated temperature and pH. The proposed MOF-based ELISA has significant potential for the clinical and diagnostic studies

Study of genotype, subtype and mutation in the S gene in hepatitis B patients co-infected with HIV in Iran

Background: Co-infection with human immunodeficiency virus (HIV) and hepatitis B virus (HBV) is common due to shared routes of transmission, as reported approximately 10% of 33 million HIV-infected patients worldwide are chronically infected with HBV. Mutations of HBsAg especially within the “a” determinant could alter the antigenicity of the protein, causing failure of HBsAg neutralization and escaping from the host’s immune system. This results in active viral replication and liver disease. Objectives: The aim of the survey was to identify HBV genotype and subtype, and different mutations in HBV S gene in hepatitis B patients co-infected with HIV in Iran. Methods: PCR performance and HBV-DNA extraction from plasma of 124 samples obtained from treatment naive HIV/HBV coinfected participants were according to the protocol. Direct sequencing and alignment of surface gene were carried out using reference sequences from the Gene Bank database. Results: From 124 HIV/HBV ELISA positive samples, 40 were HBV DNA-positive. Themean age of patients was 33.88 years. 20% of them were female and 80% were male. All isolates belonged to the sub genotype D1/ayw2 and genotype D. There were 50 point mutations including 23 (46%) missense and 27 (54%) silent mutations in amino acid level. Twenty three amino acid mutations occurred in different immune epitopes such as 11 (47.82%) in B cell, 6 (26.08%) in T helper and 2 (%8.6) in CTL. The prevalence of mutations in both “a” determinant region and Major Hydrophilic Region (MHR) was 5 (21.73%). Conclusions: Our findings showed that P127T and A70P (Outside of MHR) were the most frequently occurring substitution mutations. P127T, P132T, G130R, and S136Y substitutions placed in the first loop of the “a” determinant and the other substitutions of P142T and D144N occurred in the second loop of “a” determinant. The results of our study showed that most of the mutations occurred in B cell epitopes. The mutation in a surface gene of HBV may be selected by immune pressure or anti-retroviral therapy