40 results on '"Fatema Tuz Zahra"'
Search Results
2. Cross-reactive immunity against the SARS-CoV-2 Omicron variant is low in pediatric patients with prior COVID-19 or MIS-C
- Author
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Juanjie Tang, Tanya Novak, Julian Hecker, Gabrielle Grubbs, Fatema Tuz Zahra, Lorenza Bellusci, Sara Pourhashemi, Janet Chou, Kristin Moffitt, Natasha B. Halasa, Stephanie P. Schwartz, Tracie C. Walker, Keiko M. Tarquinio, Matt S. Zinter, Mary A. Staat, Shira J. Gertz, Natalie Z. Cvijanovich, Jennifer E. Schuster, Laura L. Loftis, Bria M. Coates, Elizabeth H. Mack, Katherine Irby, Julie C. Fitzgerald, Courtney M. Rowan, Michele Kong, Heidi R. Flori, Aline B. Maddux, Steven L. Shein, Hillary Crandall, Janet R. Hume, Charlotte V. Hobbs, Adriana H. Tremoulet, Chisato Shimizu, Jane C. Burns, Sabrina R. Chen, Hye Kyung Moon, Christoph Lange, Adrienne G. Randolph, and Surender Khurana
- Subjects
Science - Abstract
The antibody response to the SARS-CoV-2 Omicron variant is not well studied in children. Here, the authors provide an age-stratified analysis of SARS-CoV-2 neutralizing capacity of sera from children with acute or convalescent COVID-19 as well as children with multisystem inflammatory syndrome.
- Published
- 2022
- Full Text
- View/download PDF
3. Advanced bioinformatic analysis and pathway prediction of NSCLC cells upon cisplatin resistance
- Author
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A K M Nawshad Hossian, Fatema Tuz Zahra, Sagun Poudel, Camille F. Abshire, Paula Polk, Jone Garai, Jovanny Zabaleta, Constantinos M. Mikelis, and George Mattheolabakis
- Subjects
Medicine ,Science - Abstract
Abstract This study aims to identify pathway involvement in the development of cisplatin (cis-diamminedichloroplatinum (II); CDDP) resistance in A549 lung cancer (LC) cells by utilizing advanced bioinformatics software. We developed CDDP-resistant A549 (A549/DDP) cells through prolonged incubation with the drug and performed RNA-seq on RNA extracts to determine differential mRNA and miRNA expression between A549/DDP and A549 cells. We analyzed the gene dysregulation with Ingenuity Pathway Analysis (IPA; QIAGEN) software. In contrast to prior research, which relied on the clustering of dysregulated genes to pathways as an indication of pathway activity, we utilized the IPA software for the dynamic evaluation of pathway activity depending on the gene dysregulation levels. We predicted 15 pathways significantly contributing to the chemoresistance, with several of them to have not been previously reported or analyzed in detail. Among them, the PKR signaling, cholesterol biosynthesis, and TEC signaling pathways are included, as well as genes, such as PIK3R3, miR-34c-5p, and MDM2, among others. We also provide a preliminary analysis of SNPs and indels, present exclusively in A549/DDP cells. This study's results provide novel potential mechanisms and molecular targets that can be explored in future studies and assist in improving the understanding of the chemoresistance phenotype.
- Published
- 2021
- Full Text
- View/download PDF
4. Author Correction: Cross-reactive immunity against the SARS-CoV-2 Omicron variant is low in pediatric patients with prior COVID-19 or MIS-C
- Author
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Juanjie Tang, Tanya Novak, Julian Hecker, Gabrielle Grubbs, Fatema Tuz Zahra, Lorenza Bellusci, Sara Pourhashemi, Janet Chou, Kristin Moffitt, Natasha B. Halasa, Stephanie P. Schwartz, Tracie C. Walker, Keiko M. Tarquinio, Matt S. Zinter, Mary A. Staat, Shira J. Gertz, Natalie Z. Cvijanovich, Jennifer E. Schuster, Laura L. Loftis, Bria M. Coates, Elizabeth H. Mack, Katherine Irby, Julie C. Fitzgerald, Courtney M. Rowan, Michele Kong, Heidi R. Flori, Aline B. Maddux, Steven L. Shein, Hillary Crandall, Janet R. Hume, Charlotte V. Hobbs, Adriana H. Tremoulet, Chisato Shimizu, Jane C. Burns, Sabrina R. Chen, Hye Kyung Moon, Christoph Lange, Adrienne G. Randolph, and Surender Khurana
- Subjects
Science - Published
- 2022
- Full Text
- View/download PDF
5. Drivers Influencing the Adoption Intention towards Mobile Fintech Services: A Study on the Emerging Bangladesh Market
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Md. Sharif Hassan, Md. Aminul Islam, Farid Ahammad Sobhani, Hussen Nasir, Imroz Mahmud, and Fatema Tuz Zahra
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mobile fintech services (MFS) ,perceived trust ,social influence ,facilitating conditions ,perceived benefit ,Information technology ,T58.5-58.64 - Abstract
People’s acceptance of technological changes has escalated with time. However, the acceptance and adoption of fintech services hiked after the outbreak of the virulent coronavirus. With this breakout, the adoption of mobile fintech services (MFS) increased among general citizens and business sectors around the world, including in developed, emerging, and developing economies. This study aimed to identify the factors that impact the adoption intention of consumers to embrace and enhance the use of mobile fintech services in an emerging market, Bangladesh. A research model was developed to strengthen the objective of this paper. A total of 218 respondents responded to the questionnaire. The study utilized structural equation modeling to analyze the results in SmartPLS software. The results showed significant positive effects of social influence, trust, perceived benefit, and facilitating conditions on the adoption intention towards MFS. Mobile fintech service providers must keep their users’ needs and literacy rates in mind when designing the user interface (UI). Moreover, they should also cater more efficient services to the users and work based on the feedback received. The customers’ satisfaction will ultimately lead to customers conducting more digital transactions and will contribute to the escalation of fintech transactions, resulting in more financial inclusion.
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- 2022
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6. Deep insights into the optoelectronic properties of AgCdF3-based perovskite solar cell using the combination of DFT and SCAPS-1D simulation
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Fatema-Tuz- Zahra, Md Mehidi Hasan, Md. Bokhtiar Hossen, and Md. Rasidul Islam
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DFT ,AgCdF3 ,SCAPS ,Solar cell ,Optoelectronic properties ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
The main focus of this research is to explore the properties and photovoltaic application of AgCdF3, and hence, initially, the CASTEP software was used in this study to assess the structural, optical, mechanical, and electrical characteristics of the AgCdF3 perovskite absorber layer within the context of the density functional theory (DFT) method. AgCdF3 resulting from the structural research is confirmed to be chemically and thermodynamically stable by the estimated tolerance factor and formation enthalpy. According to the band structure analysis, AgCdF3 is an indirect band gap semiconductor with a band gap of 1.106 eV, where the electrons of Cd-4d and F-2s dominate the band edges of this semiconductor. Analysis of mechanical properties revealed that the AgCdF3 cubic perovskite has a stable structure and enhanced ductility, indicating superior machinability. After completing the DFT analysis, a one-dimensional solar cell capacitance simulator 1D (SCAPS-1D) was used with three popular electron transport layers (ETLs), including ZnO, PCBM, and C60, to examine the photovoltaic (PV) performance of various AgCdF3-based solar cell heterostructures. Based on simulation findings, the device design with ITO/ZnO/AgCdF3/CuI/Au showed the highest photoconversion efficiency compared to the other configurations. A detailed analysis was conducted for the aforementioned configurations to determine the impact of variations in the absorber and ETL thickness on PV performance. Moreover, the effects of the three designs were assessed in terms of function, generation and recombination rate, capacitance, operating temperature, series and shunt resistance, and Mott-Schottky. Thus, this comprehensive simulation with validation results demonstrated the true potential of AgCdF3 absorber with appropriate ETLs such as ZnO, PCBM, and C60; on the other hand, the CuI as hole transport layer (HTL), paving the way for promising studies to develop high-efficiency AgCdF3 PSCs for the photovoltaic industry.
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- 2024
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7. Pressure-driven semiconducting to metallic transition in francium tin trihalides perovskite with improved optoelectronic performance: A DFT study
- Author
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Imtiaz Ahamed Apon, M. D. Ratul Hasan, Istiak Ahmed Ovi, and Fatema-Tuz-Zahra
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Physics ,QC1-999 - Abstract
The objective of our study was to analyze the mechanical, magnetic, elastic, electrical, and optical characteristics of the halide-based perovskite FrSnX3 (X = Cl, Br, and I) at hydrostatic pressures ranging from 0 to 6 GPa. We conducted this analysis using first-principles calculations based on density functional theory. The thermodynamic and mechanical stability of the complex FrSnX3 (X = Cl, Br, and I) were calculated based on its formation enthalpy and elastic constant characteristics. The compound was found to be ductile and stable. FrSnCl3, FrSnBr3, and FrSnI3 are all classified as semiconductors according to band calculations. Their respective bandgaps are 1.046, 0.675, and 0.485 eV, respectively. These values remain constant when hydrostatic pressure is not applied. The bandgap and density of states of the three halides were examined to observe their variations with increasing induced pressure. The bandgaps of FrSnCl3, FrSnBr3, and FrSnI3 were measured to be 0 eV at pressures of 6, 4, and 2 GPa, respectively. In addition, a comprehensive study was conducted on the optical properties of cubic perovskites FrSnX3 (X = Cl, Br, and I) under different hydrostatic pressures ranging from 0 to 6 GPa. The investigation focused on analyzing the optical absorption, reflectivity, and refractive index, as well as the imaginary and real components of the dielectric functions. Under high pressure, the compound exhibited higher absorption capabilities for all compounds within the 10–13 eV range, transforming into a conductor. This property makes it well-suited for utilization in the UV spectrum. Chlorine exhibits the greatest absorption among all chemicals, whereas iodine demonstrates the least absorption. The reflectance values of all compounds range from 12% to 16% and increase with increasing pressure. At the energy level of zero, the refractive index’s real component ranges from 1.25 to 1.7, and it increases with increasing pressure. Chlorine has a relatively low refractive index compared to iodine. Bromine has the most pronounced variance. The dielectric characteristics typically vary from 4.5 to 7.5 F/m. As pressure increases, the charge storage capacities of all compounds increase. However, among these compounds, iodine has the highest capacity, while chlorine (Cl) has the lowest. The hydrostatic pressure applied to the structure FrSnX3 (X = Cl, Br, and I) causes it to become harder and more ductile. This is evident from the increasing values of the bulk, Young’s, and shear modulus, as well as the elastic constants (C11 and C12). We optimized the band structure and density of states by aligning the electrons in a co-linear location and assessed the magnetic properties. The diamagnetic characteristic of the FrSnX3 compound (where X = Cl, Br, and I) remained unchanged when subjected to increasing pressure. The results indicate that the perovskite material has exceptional absorption properties, indicating a change in its behavior from a transistor to a metal. The numerical findings highlight the potential applications of this material in photovoltaic cells, ultraviolet light absorbers, and optoelectronic devices.
- Published
- 2024
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- View/download PDF
8. The structural, magnetic, optoelectronic, and mechanical characteristics of NaGeX3 perovskites under pressure for soler-cell applications
- Author
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Istiak Ahmed Ovi, MD Ratul Hasan, Imtiaz Ahamed Apon, and Fatema-Tuz Zahra
- Subjects
density functional theory ,electronic band structure ,mulliken population analysis ,valence and conduction band ,fermi surface ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Chemical technology ,TP1-1185 - Abstract
This study examines the physical properties of germanium-based halide perovskite through Density Functional Theory (DFT) computations. The physical, optical, mechanical, and magnetic properties of NaGeX _3 (X = Cl, Br, and I) were examined with the effects of hydrostatic pressure applied externally. The compounds were subjected to pressure variations ranging from 0 to 5 GPa. The results indicate a decrease in the band gap from the infrared to the visible spectrum. For NaGeCl _3 , NaGeBr _3 , and NaGeI _3 the band gap decreased from 0.766 eV, 0.497 eV, and 0.400 eV to 0 eV, respectively, indicating the metallic behavior. The mechanical properties of NaGeX _3 (X = Cl, Br, and I) demonstrate that for all three compounds, Bulk Modulus (B), Shear Modulus (G), Young’s Modulus (E), Poisson’s ratio (ν), and Pugh’s ratio $\left(B/G\right)$ all increase with increasing pressure. It demonstrates that all these NaGeX _3 (X = Cl, Br, I) compounds are ductile in nature. The compounds are determined to be diamagnetic based on their magnetic property investigation, which reveals no notable changes in behavior up to 5 GPa of rising pressure. To gain a better understanding of the properties of the material when incident light strikes its surface, researchers also looked in at optical absorption, reflectivity, dielectric constants, refractive index, conductivity, and loss functions. Pressure-induced NaGeX _3 perovskite compounds, where X = Cl, Br, and I, show an increase in dielectric constant as pressure rises, suggesting a decrease in charge carrier recombination rates and a possibility for higher optoelectronic device efficiency. For all NaGeX _3 compounds (where X = Cl, Br, and I), the maximum absorption coefficient peaks are located around 3 eV, indicating that increasing pressure increases optical conductivity. Additionally, they have significantly low reflectance throughout the visible spectrum and very narrow band gap, which indicates significant absorption and the possibility of effective Near-Infrared (NIR) Sensors, photodetector etc applications.
- Published
- 2024
- Full Text
- View/download PDF
9. Pressure-driven semiconducting to metallic transition in francium tin trihalides perovskite with improved optoelectronic performance: A DFT study.
- Author
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Apon, Imtiaz Ahamed, Ratul Hasan, M. D., Ovi, Istiak Ahmed, and Fatema-Tuz-Zahra
- Subjects
HYDROSTATIC pressure ,HEAT of formation ,MODULUS of rigidity ,ENERGY levels (Quantum mechanics) ,PEROVSKITE ,REFRACTIVE index ,ELASTIC constants - Abstract
The objective of our study was to analyze the mechanical, magnetic, elastic, electrical, and optical characteristics of the halide-based perovskite FrSnX
3 (X = Cl, Br, and I) at hydrostatic pressures ranging from 0 to 6 GPa. We conducted this analysis using first-principles calculations based on density functional theory. The thermodynamic and mechanical stability of the complex FrSnX3 (X = Cl, Br, and I) were calculated based on its formation enthalpy and elastic constant characteristics. The compound was found to be ductile and stable. FrSnCl3 , FrSnBr3 , and FrSnI3 are all classified as semiconductors according to band calculations. Their respective bandgaps are 1.046, 0.675, and 0.485 eV, respectively. These values remain constant when hydrostatic pressure is not applied. The bandgap and density of states of the three halides were examined to observe their variations with increasing induced pressure. The bandgaps of FrSnCl3 , FrSnBr3 , and FrSnI3 were measured to be 0 eV at pressures of 6, 4, and 2 GPa, respectively. In addition, a comprehensive study was conducted on the optical properties of cubic perovskites FrSnX3 (X = Cl, Br, and I) under different hydrostatic pressures ranging from 0 to 6 GPa. The investigation focused on analyzing the optical absorption, reflectivity, and refractive index, as well as the imaginary and real components of the dielectric functions. Under high pressure, the compound exhibited higher absorption capabilities for all compounds within the 10–13 eV range, transforming into a conductor. This property makes it well-suited for utilization in the UV spectrum. Chlorine exhibits the greatest absorption among all chemicals, whereas iodine demonstrates the least absorption. The reflectance values of all compounds range from 12% to 16% and increase with increasing pressure. At the energy level of zero, the refractive index's real component ranges from 1.25 to 1.7, and it increases with increasing pressure. Chlorine has a relatively low refractive index compared to iodine. Bromine has the most pronounced variance. The dielectric characteristics typically vary from 4.5 to 7.5 F/m. As pressure increases, the charge storage capacities of all compounds increase. However, among these compounds, iodine has the highest capacity, while chlorine (Cl) has the lowest. The hydrostatic pressure applied to the structure FrSnX3 (X = Cl, Br, and I) causes it to become harder and more ductile. This is evident from the increasing values of the bulk, Young's, and shear modulus, as well as the elastic constants (C11 and C12 ). We optimized the band structure and density of states by aligning the electrons in a co-linear location and assessed the magnetic properties. The diamagnetic characteristic of the FrSnX3 compound (where X = Cl, Br, and I) remained unchanged when subjected to increasing pressure. The results indicate that the perovskite material has exceptional absorption properties, indicating a change in its behavior from a transistor to a metal. The numerical findings highlight the potential applications of this material in photovoltaic cells, ultraviolet light absorbers, and optoelectronic devices. [ABSTRACT FROM AUTHOR]- Published
- 2024
- Full Text
- View/download PDF
10. Durability of Immunity Is Low Against Severe Acute Respiratory Syndrome Coronavirus 2 Omicron BA.1, BA.2, and BA.3 Variants After Second and Third Vaccinations in Children and Young Adults With Inflammatory Bowel Disease Receiving Biologics
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Lorenza Bellusci, Fatema Tuz Zahra, Dena E. Hopkins, Juan C. Salazar, Jeffrey S. Hyams, and Surender Khurana
- Subjects
Young Adult ,Biological Products ,Hepatology ,SARS-CoV-2 ,Vaccination ,Chronic Disease ,Gastroenterology ,Humans ,COVID-19 ,Child ,Inflammatory Bowel Diseases - Published
- 2022
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11. An in vitro model of glucose transporter 1 deficiency syndrome at the blood–brain barrier using induced pluripotent stem cells
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Iqra Pervaiz, Fatema Tuz Zahra, Constantinos Marios Mikelis, and Abraham Jacob Al‐Ahmad
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Glucose Transporter Type 1 ,Cellular and Molecular Neuroscience ,Glucose ,Monosaccharide Transport Proteins ,Blood-Brain Barrier ,Induced Pluripotent Stem Cells ,Endothelial Cells ,Humans ,Biochemistry ,Carbohydrate Metabolism, Inborn Errors - Abstract
Glucose is an important source of energy for the central nervous system. Its uptake at the blood-brain barrier (BBB) is mostly mediated via glucose transporter 1 (GLUT1), a facilitated transporter encoded by the SLC2A1 gene. GLUT1 Deficiency Syndrome (GLUT1DS) is a haploinsufficiency characterized by mutations in the SLC2A1 gene, resulting in impaired glucose uptake at the BBB and clinically characterized by epileptic seizures and movement disorder. A major limitation is an absence of in vitro models of the BBB reproducing the disease. This study aimed to characterize an in vitro model of GLUT1DS using human pluripotent stem cells (iPSCs). Two GLUT1DS clones were generated (GLUT1-iPSC) from their original parental clone iPS(IMR90)-c4 by CRISPR/Cas9 and differentiated into brain microvascular endothelial cells (iBMECs). Cells were characterized in terms of SLC2A1 expression, changes in the barrier function, glucose uptake and metabolism, and angiogenesis. GLUT1DS iPSCs and iBMECs showed comparable phenotype to their parental control, with exception of reduced GLUT1 expression at the protein level. Although no major disruption in the barrier function was reported in the two clones, a significant reduction in glucose uptake accompanied by an increase in glycolysis and mitochondrial respiration was reported in both GLUT1DS-iBMECs. Finally, impaired angiogenic features were reported in such clones compared to the parental clone. Our study provides the first documented characterization of GLUT1DS-iBMECs generated by CRISPR-Cas9, suggesting that GLUT1 truncation appears detrimental to brain angiogenesis and brain endothelial bioenergetics, but maybe not be detrimental to iBMECs differentiation and barriergenesis. Our future direction is to further characterize the functional outcome of such truncated product, as well as its impact on other cells of the neurovascular unit.
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- 2022
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12. Do Peripheral Development Increase Vulnerability? Case Study from Dhaka, Bangladesh
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Anisur Rahman, Chaweewan Denpaiboon, Sultana Ashrafi, and Fatema Tuz Zahra Oyshe
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General Earth and Planetary Sciences ,General Environmental Science - Published
- 2022
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13. Thickness-Dependent Ferroelectric Properties of La0.5pr0.5feo3: A Simulation-Based Study
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Fatema Tuz Zahra and Md. Rafiqul Islam
- Published
- 2023
- Full Text
- View/download PDF
14. Advanced bioinformatic analysis and pathway prediction of NSCLC cells upon cisplatin resistance
- Author
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Jone Garai, Jovanny Zabaleta, Constantinos M. Mikelis, Camille F Abshire, George Mattheolabakis, Paula Polk, A K M Nawshad Hossian, Sagun Poudel, and Fatema Tuz Zahra
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Cellular signalling networks ,Science ,Biology ,Article ,Phosphatidylinositol 3-Kinases ,eIF-2 Kinase ,Carcinoma, Non-Small-Cell Lung ,medicine ,Cancer genomics ,Humans ,RNA, Messenger ,Cancer models ,Gene ,A549 cell ,Cisplatin ,Messenger RNA ,Multidisciplinary ,Computational Biology ,Proto-Oncogene Proteins c-mdm2 ,RNA sequencing ,Protein kinase R ,Phenotype ,Computational biology and bioinformatics ,respiratory tract diseases ,Gene Expression Regulation, Neoplastic ,MicroRNAs ,Cholesterol ,A549 Cells ,Drug Resistance, Neoplasm ,Cancer research ,biology.protein ,Next-generation sequencing ,Mdm2 ,Medicine ,Signal transduction ,Lung cancer ,Non-small-cell lung cancer ,medicine.drug ,Signal Transduction - Abstract
This study aims to identify pathway involvement in the development of cisplatin (cis-diamminedichloroplatinum (II); CDDP) resistance in A549 lung cancer (LC) cells by utilizing advanced bioinformatics software. We developed CDDP-resistant A549 (A549/DDP) cells through prolonged incubation with the drug and performed RNA-seq on RNA extracts to determine differential mRNA and miRNA expression between A549/DDP and A549 cells. We analyzed the gene dysregulation with Ingenuity Pathway Analysis (IPA; QIAGEN) software. In contrast to prior research, which relied on the clustering of dysregulated genes to pathways as an indication of pathway activity, we utilized the IPA software for the dynamic evaluation of pathway activity depending on the gene dysregulation levels. We predicted 15 pathways significantly contributing to the chemoresistance, with several of them to have not been previously reported or analyzed in detail. Among them, the PKR signaling, cholesterol biosynthesis, and TEC signaling pathways are included, as well as genes, such as PIK3R3, miR-34c-5p, and MDM2, among others. We also provide a preliminary analysis of SNPs and indels, present exclusively in A549/DDP cells. This study's results provide novel potential mechanisms and molecular targets that can be explored in future studies and assist in improving the understanding of the chemoresistance phenotype.
- Published
- 2021
15. Modeling GLUT1 deficiency syndrome in a Petri Dish using induced pluripotent stem cells: A preliminary report
- Author
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Abraham Jacob Al-Ahmad, Iqra Pervaiz, Fatema Tuz-Zahra, and Constantinos Mikelis
- Abstract
Background: Glucose is an important source of energy for the central nervous system. The entry of glucose is tightly regulated by the blood-brain barrier (BBB), mediated mostly through the presence of glucose transporter 1 (GLUT1), a facilitated transporter belonging to the solute carrier superfamily (SLCs). GLUT1 Deficiency Syndrome (GLUT1DS) is a haploinsufficiency characterized by mutations in the SLC2A1 gene and resulting in impaired glucose uptake at the BBB. This preliminary study provides the characterization of a novel GLUT1DS in vitro model based on an established human induced pluripotent stem cell line (iPSC) genetically edited by CRISPR/Cas9.Methods: The human iPS(IMR90)-c4 iPSC cell line was genetically edited via CRISPR/Cas9, resulting in a SLC2A1+/- genotype (GLUT1DS-iPSC). Cells were differentiated in brain microvascular endothelial cells (iBMECs) as previously reported. Cells were characterized in terms of SLC2A1 expression, changes in the barrier function, and glucose uptake.Results: Two GLUT1DS-iPSC clones were generated and characterized in this study: C7 and E8. In undifferentiated iPSCs, both showed comparable phenotype than their parental control, and both differentiated into iBMECs. Both C7- and E8-iBMECs showed a decrease in GLUT1 expression, with C7 showing accentuated decrease. No major disruption in the barrier function was reported. However, we noted a significant decrease in glucose uptake in both clones.Conclusions: Our study provides the first documented characterization of GLUT1DS-iBMECs generated by CRISPR-Cas9, showing little effect on SLC2A1 deletion on the ability of iPSCs to differentiate into iBMECs and their ability to form tight monolayers. However, an impaired glucose uptake associated with increased mitochondrial respiration and impaired angiogenesis suggests that such deletion may affect other functions in endothelial cells. Hence, a further investigation of how SLC2A1 depletion impacts brain endothelial cells and other cellular components of the neurovascular unit is needed.
- Published
- 2022
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16. Neutralization of Severe Acute Respiratory Syndrome Coronavirus 2 Omicron and Other Variants in Serum From Children With Vaccination-Induced Myocarditis
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Fatema Tuz Zahra, Gabrielle Grubbs, Kirsten Dummer, Adriana H Tremoulet, Chisato Shimizu, Jane C Burns, and Surender Khurana
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Microbiology (medical) ,Omicron ,Cardiovascular ,Antibodies, Viral ,Medical and Health Sciences ,Microbiology ,Antibodies ,Vaccine Related ,Clinical Research ,Neutralization Tests ,Biodefense ,Humans ,Viral ,Child ,Neutralizing ,Lung ,Pediatric ,SARS-CoV-2 ,Prevention ,Vaccination ,COVID-19 ,Pneumonia ,Biological Sciences ,Antibodies, Neutralizing ,Myocarditis ,Emerging Infectious Diseases ,Infectious Diseases ,Good Health and Well Being ,Pneumonia & Influenza ,Immunization - Abstract
Our study demonstrates that children who developed severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccination-induced myocarditis and may not receive another vaccination, could be susceptible to infection with Omicron and emerging variants. We observed higher neutralizing antibody titers in myocarditis patients vs. healthy vaccinated children, but significantly lower neutralization titers against Omicron in both groups.
- Published
- 2022
17. Do Peripheral Development Increase Vulnerability? Case Study from Dhaka, Bangladesh
- Author
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Rahman, Anisur, primary, Denpaiboon, Chaweewan, additional, Ashrafi, Sultana, additional, and Oyshe, Fatema Tuz Zahra, additional
- Published
- 2022
- Full Text
- View/download PDF
18. Neutralisation of circulating SARS-CoV-2 delta and omicron variants by convalescent plasma and SARS-CoV-2 hyperimmune intravenous human immunoglobulins for treatment of COVID-19
- Author
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Fatema Tuz Zahra, Lorenza Bellusci, Gabrielle Grubbs, Hana Golding, and Surender Khurana
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Rheumatology ,Immunology ,Immunology and Allergy ,General Biochemistry, Genetics and Molecular Biology - Published
- 2022
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19. Evaluation of anthelmintic activity of ethanolic extracts of Carica papaya leaves using Paramphistomum cervi and Haemonchus contortus
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Shahnaj Parvin, Tazmel Haque, Syeda Fatema Tuz Zahra, Md. Rabiul Islam, S. M. Ibrahim Sumon, Moudud Ahmed, Kamrul Hasan, and Md. Abu Talha Siddique
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Pharmacology ,Traditional medicine ,biology ,010405 organic chemistry ,Pharmaceutical Science ,biology.organism_classification ,01 natural sciences ,0104 chemical sciences ,Time of death ,Albendazole ,010404 medicinal & biomolecular chemistry ,parasitic diseases ,medicine ,Anthelmintic ,Paramphistomum cervi ,Carica ,Piperazine Citrate ,medicine.drug ,Haemonchus contortus - Abstract
The aim of this present study is to evaluate the anthelmintic activity of leaves extracts of Carica papaya using Paramphistomum cervi and Haemonchus contortus as the test worms. A range of concentrations (100, 50 and 25%) of ethanolic extracts of C. papaya were tested to assay the procedure. This is mainly applied for the determination of time of death (D) and time of paralysis (P) of the tested worms. After the analysis, it was shown that for the H. contortus at 100% concentration, the paralysis occurred within the shortest time (P=24.5 min) and death came at the lowest possible time (D=56 min). The time of death and paralysis increased at 50% (D=64 min and P=28 min) and 25% concentration (D=74 min and P=34 min), respectively compared to the Piperazine citrate (P= 24 min and D= 54) at concentration of 10 mg/ml. Here, distilled water is as a control solution. The results of this study revealed that the ethanolic extracts of the leaves of the C. papaya expressed a demonstrated paralysis significantly, and also responsible for the death of P. cervi and H. contortus especially at the higher concentration (100%) compared to the standard reference of Piperazine citrate. Therefore, from the results it is declared that the ethanolic extracts of the leaves of C. papaya showed a great anthelmintic activity against P. cervi and H. contortus worms. Hence, the present research work signifies that the leaf of C. papaya has a major anthelmintic activity and also can be used as a potent drug for its low cost and availability. Key words: Paramphistomum cervi and Haemonchus contortus, anthelmintic, Carica papaya leaves, Albendazole.
- Published
- 2019
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20. The Regulatory Activity of GIPC1 on RhoA‐Mediated bFGF Angiogenic Functions
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Constantinos M. Mikelis, Vasileios Oikonomou, Mihalis S. Lionakis, Laurence Wood, Fatema Tuz Zahra, Racheal G Akwii, Sanaullah Sajib, and Paul Tullar
- Subjects
RHOA ,biology ,Chemistry ,Genetics ,biology.protein ,Molecular Biology ,Biochemistry ,Biotechnology ,Cell biology - Published
- 2021
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21. Angiopoietin-2-induced lymphatic endothelial cell migration drives lymphangiogenesis via the β1 integrin-RhoA-formin axis
- Author
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Racheal Grace Akwii, Md. Sanaullah Sajib, Fatema Tuz Zahra, Paul Tullar, Masoud Zabet-Moghaddam, Yi Zheng, J. Silvio Gutkind, Colleen L. Doci, and Constantinos M. Mikelis
- Subjects
Angiopoietin-2 ,Cancer Research ,Physiology ,Integrin beta1 ,Clinical Biochemistry ,Endothelial Cells ,Formins ,Humans ,Lymphangiogenesis ,rhoA GTP-Binding Protein ,Receptor, TIE-2 - Abstract
Lymphangiogenesis is an essential physiological process but also a determining factor in vascular-related pathological conditions. Angiopoietin-2 (Ang2) plays an important role in lymphatic vascular development and function and its upregulation has been reported in several vascular-related diseases, including cancer. Given the established role of the small GTPase RhoA on cytoskeleton-dependent endothelial functions, we investigated the relationship between RhoA and Ang2-induced cellular activities. This study shows that Ang2-driven human dermal lymphatic endothelial cell migration depends on RhoA. We demonstrate that Ang2-induced migration is independent of the Tie receptors, but dependent on β1 integrin-mediated RhoA activation with knockdown, pharmacological approaches, and protein sequencing experiments. Although the key proteins downstream of RhoA, Rho kinase (ROCK) and myosin light chain, were activated, blockade of ROCK did not abrogate the Ang2-driven migratory effect. However, formins, an alternative target of RhoA, were identified as key players, and especially FHOD1. The Ang2-RhoA relationship was explored in vivo, where lymphatic endothelial RhoA deficiency blocked Ang2-induced lymphangiogenesis, highlighting RhoA as an important target for anti-lymphangiogenic treatments.
- Published
- 2021
22. An Improved Adaptive Optimization Technique for Image Classification
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Nazmus Saqib and Fatema Tuz Zahra
- Subjects
Contextual image classification ,Artificial neural network ,Computer science ,Generalization ,business.industry ,Adaptive optimization ,Adaptive system ,Deep learning ,Pattern recognition ,Artificial intelligence ,Gradient descent ,business ,MNIST database - Abstract
In deep learning, the optimization techniques are the most part dependent on gradient descent methods, such as SGD, Adam; adopt the leading place in the area of optimization methods. Conventional methodologies which depend on stochastic gradients are non-adaptive because the prescribed parameter worth's usage should be tuned for every application. However, the generalization performance of the stochastic optimizers is far superior to the adaptive methods, whereas Adam and its variants cannot maintain this without a fast convergence rate in deep neural networks. To improve this generalization performance, we need to diminish the oscillation of the weights, the general problem of the accuracy fall. To stable the generalization performance, we have introduced Mean-ADAM, a variance of Adam, extends the updated weights by an external weight to diminish the oscillation and overcome a superior accuracy rate than all other adaptive gradient methods till the conclusion of the training. Therefore, we substantially improve the generalization performance, permit it to contend with the existing algorithms on different image classification datasets such as Mnist, Cifar 10, Cifar 100, ImageNet, etc. We have attained 82% at 150 th epochs with Cifar 10 and 99.49% with Mnist where the Adam has indicated 76% and 99.43% individually. The graphical statistics and the quantitative results can indicate that the proposed method is more likely to perform in more diverse image datasets.
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- 2020
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23. In Vivo Ear Sponge Lymphangiogenesis Assay
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Hanumantha Rao Madala, Fatema Tuz Zahra, Racheal G Akwii, Kalkunte S. Srivenugopal, Sanaullah Sajib, and Constantinos M. Mikelis
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0301 basic medicine ,Cancer metastasis ,Biology ,medicine.disease ,Lymphangiogenesis ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Lymphatic system ,Lymphedema ,Immune system ,In vivo ,030220 oncology & carcinogenesis ,Cancer research ,medicine ,Tie signaling pathway ,Tumor growth - Abstract
Lymphangiogenesis, the formation of lymphatic vessels from preexisting ones, is an important process in wound-healing physiology. Deregulation of lymphangiogenesis and lymphatic vascular remodeling have been implicated in a range of inflammatory conditions, such as lymphedema, lymphadenopathy, tumor growth, and cancer metastasis. Any attempt in understanding various parameters of the lymphangiogenic process and developing desirable therapeutic targets requires recapitulating these conditions in in vivo models. One pitfall with some experimental models is the absence of immune response, an important regulatory factor for lymphangiogenesis. We overcome this issue by using immune competent mice. In this chapter, by using Angiopoietin-2 (Ang2), a protein that belongs to the Ang/Tie signaling pathway, we describe the ear sponge assay with important adaptations, highlighting a reproducible and quantitative tool for assessment of in vivo lymphangiogenesis.
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- 2020
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24. Identification of Rho GEF and RhoA Activation by Pull-Down Assays
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Sanaullah Sajib, Constantinos M. Mikelis, Racheal G Akwii, and Fatema Tuz Zahra
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0301 basic medicine ,RHOA ,Guanine Nucleotide Dissociation Inhibitors ,030102 biochemistry & molecular biology ,biology ,GTP' ,Chemistry ,Guanosine triphosphate ,Cell biology ,03 medical and health sciences ,chemistry.chemical_compound ,030104 developmental biology ,Microtubule ,Guanosine diphosphate ,biology.protein ,Small GTPase ,Guanine nucleotide exchange factor - Abstract
The small GTPase RhoA participates in actin and microtubule machinery, cell migration and invasion, gene expression, vesicular trafficking and cell cycle, and its dysregulation is a determining factor in many pathological conditions. Similar to other Rho GTPases, RhoA is a key component of the wound-healing process, regulating the activity of different participating cell types. RhoA gets activated upon binding to guanine nucleotide exchange factors (GEFs), which catalyze the exchange of guanosine diphosphate (GDP) for guanosine triphosphate (GTP). GTPase-activating proteins (GAPs) mediate the exchange of GTP to GDP, inactivating RhoA, whereas guanine nucleotide dissociation inhibitors (GDIs) preserve the inactive pool of RhoA proteins in the cytosol. RhoA and Rho GEF activation is detected by protein pull-down assays, which use chimeric proteins with Rhotekin and G17A mutant RhoA as "bait" to pull down active RhoA and RhoA GEFs, respectively. In this chapter, we describe an optimized protocol for performing RhoA and GEF pull-down assays.
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- 2020
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25. Low Dose of Penfluridol Inhibits VEGF-Induced Angiogenesis
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Sanjay K. Srivastava, Fatema Tuz Zahra, Paul Tullar, Constantinos M. Mikelis, Nehal Gupta, and Suyash Srivastava
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Vascular Endothelial Growth Factor A ,Angiogenesis ,Angiogenesis Inhibitors ,Penfluridol ,Metastasis ,lcsh:Chemistry ,Mice ,angiogenesis ,0302 clinical medicine ,Cell Movement ,penfluridol ,Tumor Microenvironment ,lcsh:QH301-705.5 ,Spectroscopy ,Tube formation ,0303 health sciences ,Chemistry ,Cell migration ,General Medicine ,3. Good health ,Computer Science Applications ,Endothelial stem cell ,Drug Combinations ,030220 oncology & carcinogenesis ,Female ,Proteoglycans ,Collagen ,medicine.drug ,Antipsychotic Agents ,Signal Transduction ,Cell Survival ,Breast Neoplasms ,Catalysis ,Article ,Inorganic Chemistry ,03 medical and health sciences ,breast cancer ,Cell Line, Tumor ,medicine ,Human Umbilical Vein Endothelial Cells ,Animals ,Humans ,Physical and Theoretical Chemistry ,Molecular Biology ,030304 developmental biology ,Cell Proliferation ,Tumor microenvironment ,Organic Chemistry ,medicine.disease ,Vascular Endothelial Growth Factor Receptor-2 ,Mice, Inbred C57BL ,lcsh:Biology (General) ,lcsh:QD1-999 ,Cancer cell ,Cancer research ,Laminin - Abstract
Metastasis is considered a major burden in cancer, being responsible for more than 90% of cancer-related deaths. Tumor angiogenesis is one of the main processes that lead to tumor metastasis. Penfluridol is a classic and commonly used antipsychotic drug, which has a great ability to cross the blood&ndash, brain barrier. Recent studies have revealed that penfluridol has significant anti-cancer activity in diverse tumors, such as metastatic breast cancer and glioblastoma. Here, we aim to identify the effect of low doses of penfluridol on tumor microenvironment and compare it with its effect on tumor cells. Although low concentration of penfluridol was not toxic for endothelial cells, it blocked angiogenesis in vitro and in vivo. In vitro, penfluridol inhibited VEGF-induced primary endothelial cell migration and tube formation, and in vivo, it blocked VEGF- and FGF-induced angiogenesis in the matrigel plug assay. VEGF-induced VEGFR2 phosphorylation and the downstream p38 and ERK signaling pathways were not affected in endothelial cells, although VEGF-induced Src and Akt activation were abrogated by penfluridol treatment. When cancer cells were treated with the same low concentration of penfluridol, basal Src activation levels were mildly impaired, thus impacting their cell migration and wound healing efficiency. The potential of cancer-induced paracrine effect on endothelial cells was explored, although that did not seem to be a player for angiogenesis. Overall, our data demonstrates that low penfluridol levels, similar to the ones clinically used for anti-psychotic conditions, suppress angiogenic efficiency in the tumor microenvironment.
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- 2020
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26. Pharmacogenetic Variants in MTHFR Gene are Significant Predictors of Methotrexate Toxicities in Bangladeshi Patients With Acute Lymphoblastic Leukemia
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Noor Ahmed Nahid, Maizbha Uddin Ahmed, Abul Hasnat, Fatema Tuz Zahra, Mohd Nazmul Hasan Apu, Mir Md. Abdullah Al-Mamun, Md. Reazul Islam, Zabun Nahar, Amin Lutful Kabir, Subrata K. Biswas, and Mohammad Safiqul Islam
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0301 basic medicine ,Adult ,Male ,Cancer Research ,medicine.medical_specialty ,Homocysteine ,Adolescent ,Pharmacogenomic Variants ,Pharmacogenetic Study ,Gastroenterology ,03 medical and health sciences ,chemistry.chemical_compound ,Young Adult ,0302 clinical medicine ,Internal medicine ,Genotype ,medicine ,Mucositis ,Humans ,Child ,Methylenetetrahydrofolate Reductase (NADPH2) ,Bangladesh ,Methionine ,biology ,business.industry ,Hematology ,Middle Aged ,Precursor Cell Lymphoblastic Leukemia-Lymphoma ,medicine.disease ,digestive system diseases ,030104 developmental biology ,Methotrexate ,Oncology ,chemistry ,030220 oncology & carcinogenesis ,Methylenetetrahydrofolate reductase ,Child, Preschool ,biology.protein ,Female ,business ,Pharmacogenetics ,medicine.drug - Abstract
Background The objective of this pharmacogenetic study was to investigate the relationship of methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms with methotrexate (MTX)-induced toxicities and plasma homocysteine level in patients with acute lymphoblastic leukemia (ALL) from Bangladesh. Several polymorphisms result in reduced MTHFR activity that causes impaired remethylation of homocysteine to methionine and abnormal MTX metabolism, especially in tissues with high turnover. Therefore, the risk of elevated plasma homocysteine as well as MTX-induced toxicities become higher with MTHFR polymorphisms. Patients and Methods We recruited 160 patients with ALL receiving MTX containing chemotherapeutic protocol, and they were genotyped for MTHFR C677T and A1298C polymorphisms with polymerase chain reaction-restriction fragment length polymorphism. We also measured the plasma homocysteine level of 51 patients by the AxSYM homocysteine assay method. Results We found 68.1% CC, 26.3% CT, and 5.6% TT genotype for MTHFR C677T polymorphism and 39.3% AA, 46.9% AC, and 13.8% CC genotype for MTHFR A1298C polymorphism in patients with ALL. Our study suggested that MTX-induced mucositis and diarrhea are significantly associated with MTHFR C677T as well as MTHFR A1298C polymorphisms (P Conclusion The risk of elevated plasma homocysteine level was 5 to 6 times higher for both polymorphisms. This study may help to identify the patients who are at higher risk for MTX-related toxicities.
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- 2019
27. Role of Angiopoietin-2 in Vascular Physiology and Pathophysiology
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Fatema Tuz Zahra, Racheal G Akwii, Sanaullah Sajib, and Constantinos M. Mikelis
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Angiogenesis ,integrin ,medicine.medical_treatment ,Neovascularization, Physiologic ,Inflammation ,Review ,Receptor tyrosine kinase ,TIE1 ,Capillary Permeability ,Mice ,03 medical and health sciences ,angiogenesis ,0302 clinical medicine ,Biomarkers, Tumor ,medicine ,Animals ,Humans ,cancer ,Receptor ,lcsh:QH301-705.5 ,030304 developmental biology ,0303 health sciences ,Neovascularization, Pathologic ,biology ,Growth factor ,Angiopoietins ,Receptor, TIE-1 ,General Medicine ,Receptor, TIE-2 ,Angiopoietin receptor ,endothelial cells ,Cell biology ,Tie2 ,Tie1 ,lcsh:Biology (General) ,inflammation ,030220 oncology & carcinogenesis ,cardiovascular system ,biology.protein ,angiopoietin-2 ,Endothelium, Vascular ,Endothelium, Lymphatic ,medicine.symptom - Abstract
Angiopoietins 1–4 (Ang1–4) represent an important family of growth factors, whose activities are mediated through the tyrosine kinase receptors, Tie1 and Tie2. The best characterized are angiopoietin-1 (Ang1) and angiopoietin-2 (Ang2). Ang1 is a potent angiogenic growth factor signaling through Tie2, whereas Ang2 was initially identified as a vascular disruptive agent with antagonistic activity through the same receptor. Recent data demonstrates that Ang2 has context-dependent agonist activities. Ang2 plays important roles in physiological processes and the deregulation of its expression is characteristic of several diseases. In this review, we summarize the activity of Ang2 on blood and lymphatic endothelial cells, its significance in human physiology and disease, and provide a current view of the molecular signaling pathways regulated by Ang2 in endothelial cells.
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- 2019
28. Role of Endothelial RhoA in Melanoma and Lung Cancer Trans‐endothelial Migration and Metastasis
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Sanaullah Sajib, Ulrich Bickel, Fatema Tuz Zahra, Sanjay K. Srivastava, Constantinos M. Mikelis, Jee Hyun Park, and Paul Tullar
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RHOA ,biology ,business.industry ,Melanoma ,medicine.disease ,Biochemistry ,Metastasis ,Genetics ,medicine ,biology.protein ,Cancer research ,Lung cancer ,business ,Molecular Biology ,Biotechnology - Published
- 2019
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29. Endothelial RhoA Regulates Breast Cancer Metastasis
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Sanjay K. Srivastava, Jee Hyun Park, Paul Tullar, Fatema Tuz Zahra, Ulrich Bickel, Sanaullah Sajib, and Constantinos M. Mikelis
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RHOA ,biology ,business.industry ,Genetics ,Cancer research ,biology.protein ,Medicine ,Breast cancer metastasis ,business ,Molecular Biology ,Biochemistry ,Biotechnology - Published
- 2019
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30. Involvement of Endothelial Small GTPase RhoA in Angiogenesis In Vitro and In Vivo
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Yusuke Ichiyama, Yoshiaki Kubota, Fatema Tuz Zahra, Sanaullah Sajib, Racheal G Akwii, Paul Tullar, and Constantinos M. Mikelis
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RHOA ,biology ,Chemistry ,In vivo ,Angiogenesis ,Genetics ,biology.protein ,Small GTPase ,Molecular Biology ,Biochemistry ,In vitro ,Biotechnology ,Cell biology - Published
- 2019
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31. In Vitro Spheroid Sprouting Assay of Angiogenesis
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Fatema Tuz, Zahra, Efrossini, Choleva, Md Sanaullah, Sajib, Evangelia, Papadimitriou, and Constantinos M, Mikelis
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Microscopy, Confocal ,Staining and Labeling ,Spheroids, Cellular ,Cell Culture Techniques ,Human Umbilical Vein Endothelial Cells ,Endothelial Cells ,Humans ,Neovascularization, Physiologic ,Collagen ,Extracellular Matrix - Abstract
Angiogenesis is a well-coordinated physiological process that leads to new blood vessel formation. Physiologically, angiogenesis is more prominent during development and wound healing and its dysregulation drives or is related to several diseases, including cancer. The endothelial cells are the main regulators of the angiogenic process, and thus the angiogenic outcome is assessed based on the effect on endothelial cell functions. Several in vitro and in vivo techniques have been developed to assess the effect of various factors on angiogenesis. Compared to the in vivo techniques, the in vitro techniques are considered less physiologically relevant. This has been partially overcome by the development of 3-dimensional (3D) in vitro models, one of which is the spheroid assay or 3D sprouting assay that exploits the effect of the extracellular matrix to endothelial cell functions. This chapter focuses on the description of the spheroid assay and mentions the variations and potential applications this assay can have.
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- 2019
32. Matrigel Plug Assay for In Vivo Evaluation of Angiogenesis
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Pinelopi, Kastana, Fatema Tuz, Zahra, Despoina, Ntenekou, Stamatiki, Katraki-Pavlou, Dimitris, Beis, Michail S, Lionakis, Constantinos M, Mikelis, and Evangelia, Papadimitriou
- Subjects
Membrane Glycoproteins ,Paraffin Embedding ,Staining and Labeling ,Endothelial Cells ,Neovascularization, Physiologic ,Cell Separation ,Microtomy ,Flow Cytometry ,Mice, Inbred C57BL ,Drug Combinations ,Microscopy, Fluorescence ,Animals ,Proteoglycans ,Collagen ,Laminin - Abstract
Matrigel is extracted from the Engelbreth-Holm-Swarm (EHS) mouse sarcoma in C57BL/6 mice, a tumor rich in extracellular matrix (ECM) proteins. It consists mainly of laminin (approximately 60%), collagen IV (approximately 30%), and nidogen-1/entactin (approximately 8%), while it also contains heparan sulfate proteoglycans, such as perlecan, other ECM proteins, as well as growth factors bound to the ECM. Matrigel mimics the physiological cell matrix and is the most commonly used matrix substrate to study in vitro and in vivo angiogenesis. Here, we describe the in vivo Matrigel plug assay and how it can be used for both qualitative and quantitative assessment of angiogenesis.
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- 2019
33. Matrigel Plug Assay for In Vivo Evaluation of Angiogenesis
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Fatema Tuz Zahra, Dimitris Beis, Despoina Ntenekou, Evangelia Papadimitriou, Michail S. Lionakis, Stamatiki Katraki-Pavlou, Pinelopi Kastana, and Constantinos M. Mikelis
- Subjects
0301 basic medicine ,Matrigel ,biology ,Angiogenesis ,Chemistry ,Perlecan ,Matrix (biology) ,In vitro ,Cell biology ,Extracellular matrix ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,In vivo ,Laminin ,030220 oncology & carcinogenesis ,biology.protein - Abstract
Matrigel is extracted from the Engelbreth-Holm-Swarm (EHS) mouse sarcoma in C57BL/6 mice, a tumor rich in extracellular matrix (ECM) proteins. It consists mainly of laminin (approximately 60%), collagen IV (approximately 30%), and nidogen-1/entactin (approximately 8%), while it also contains heparan sulfate proteoglycans, such as perlecan, other ECM proteins, as well as growth factors bound to the ECM. Matrigel mimics the physiological cell matrix and is the most commonly used matrix substrate to study in vitro and in vivo angiogenesis. Here, we describe the in vivo Matrigel plug assay and how it can be used for both qualitative and quantitative assessment of angiogenesis.
- Published
- 2019
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- View/download PDF
34. In Vitro Spheroid Sprouting Assay of Angiogenesis
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Sanaullah Sajib, Constantinos M. Mikelis, Fatema Tuz Zahra, Efrossini Choleva, and Evangelia Papadimitriou
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0303 health sciences ,In Vitro Techniques ,Chemistry ,Angiogenesis ,Spheroid ,02 engineering and technology ,021001 nanoscience & nanotechnology ,In vitro ,Cell biology ,Endothelial stem cell ,Extracellular matrix ,03 medical and health sciences ,In vivo ,0210 nano-technology ,Wound healing ,030304 developmental biology - Abstract
Angiogenesis is a well-coordinated physiological process that leads to new blood vessel formation. Physiologically, angiogenesis is more prominent during development and wound healing and its dysregulation drives or is related to several diseases, including cancer. The endothelial cells are the main regulators of the angiogenic process, and thus the angiogenic outcome is assessed based on the effect on endothelial cell functions. Several in vitro and in vivo techniques have been developed to assess the effect of various factors on angiogenesis. Compared to the in vivo techniques, the in vitro techniques are considered less physiologically relevant. This has been partially overcome by the development of 3-dimensional (3D) in vitro models, one of which is the spheroid assay or 3D sprouting assay that exploits the effect of the extracellular matrix to endothelial cell functions. This chapter focuses on the description of the spheroid assay and mentions the variations and potential applications this assay can have.
- Published
- 2019
- Full Text
- View/download PDF
35. Role of bFGF in Acquired Resistance upon Anti-VEGF Therapy in Cancer
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Md. Sanaullah Sajib, Constantinos M. Mikelis, and Fatema Tuz Zahra
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0301 basic medicine ,Cancer Research ,Angiogenesis ,VEGF receptors ,Basic fibroblast growth factor ,Review ,lcsh:RC254-282 ,anti-angiogenic therapy ,resistance ,angiogenesis ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Acquired resistance ,Downregulation and upregulation ,medicine ,cancer ,biology ,business.industry ,Cancer ,lcsh:Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,medicine.disease ,VEGF ,Vascular endothelial growth factor ,030104 developmental biology ,bFGF ,Oncology ,chemistry ,030220 oncology & carcinogenesis ,Cancer research ,biology.protein ,Signal transduction ,business - Abstract
Simple Summary Anti-angiogenic therapies targeting the vascular endothelial growth factor (VEGF) signaling are established in the arsenal of cancer treatments. Despite the expectations, their benefits are temporary in cancer patients, partly due to the compensatory function of other angiogenic growth factors. This review focuses on the role of basic fibroblast growth factor (bFGF), one of the highly implicated players in the emergence of resistance to anti-angiogenic approaches. Here, we summarize data from various tumor types where bFGF is upregulated after anti-angiogenic treatment, the molecular mechanisms involved, and we highlight the current status and future perspectives of multi-target anti-angiogenic drugs for cancer. Abstract Anti-angiogenic approaches targeting the vascular endothelial growth factor (VEGF) signaling pathway have been a significant research focus during the past decades and are well established in clinical practice. Despite the expectations, their benefit is ephemeral in several diseases, including specific cancers. One of the most prominent side effects of the current, VEGF-based, anti-angiogenic treatments remains the development of resistance, mostly due to the upregulation and compensatory mechanisms of other growth factors, with the basic fibroblast growth factor (bFGF) being at the top of the list. Over the past decade, several anti-angiogenic approaches targeting simultaneously different growth factors and their signaling pathways have been developed and some have reached the clinical practice. In the present review, we summarize the knowledge regarding resistance mechanisms upon anti-angiogenic treatment, mainly focusing on bFGF. We discuss its role in acquired resistance upon prolonged anti-angiogenic treatment in different tumor settings, outline the reported resistance mechanisms leading to bFGF upregulation, and summarize the efforts and outcome of combined anti-angiogenic approaches to date.
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- 2021
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36. Endothelial Small GTPase RhoA: A Potential Target for Anti‐angiogenic Therapy
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Mihalis S. Lionakis, Fatema Tuz Zahra, Paul Tullar, Racheal G Akwii, Constantinos M. Mikelis, and Sanaullah Sajib
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RHOA ,biology ,Chemistry ,Anti angiogenic ,Genetics ,biology.protein ,Cancer research ,Small GTPase ,Molecular Biology ,Biochemistry ,Biotechnology - Published
- 2020
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37. Evaluation of anthelmintic activity of ethanolic extracts of Carica papaya leaves using Paramphistomum cervi and Haemonchus contortus
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Md., Rabiul Islam, primary, Syeda, Fatema Tuz Zahra, additional, S., M. Ibrahim Sumon, additional, Shahnaj, Parvin, additional, Kamrul, Hasan, additional, Moudud, Ahmed, additional, Md., Abu Talha Siddique, additional, and Tazmel, Haque, additional
- Published
- 2019
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38. Mechanisms of angiogenesis in microbe-regulated inflammatory and neoplastic conditions
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Michail S. Lionakis, Sanaullah Sajib, Nadezhda A. German, Constantinos M. Mikelis, and Fatema Tuz Zahra
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0301 basic medicine ,Inflammation ,Cancer Research ,Angiogenic Process ,Neovascularization, Pathologic ,Physiology ,Angiogenesis ,Microbiota ,Clinical Biochemistry ,Biology ,Inflammatory Bowel Diseases ,Cell biology ,03 medical and health sciences ,030104 developmental biology ,PATHOLOGICAL DISORDERS ,Gastritis ,Neoplasms ,Humans ,Homeostasis - Abstract
Commensal microbiota inhabit all the mucosal surfaces of the human body. It plays significant roles during homeostatic conditions, and perturbations in numbers and/or products are associated with several pathological disorders. Angiogenesis, the process of new vessel formation, promotes embryonic development and critically modulates several biological processes during adulthood. Indeed, deregulated angiogenesis can induce or augment several pathological conditions. Accumulating evidence has implicated the angiogenic process in various microbiota-associated human diseases. Herein, we critically review diseases that are regulated by microbiota and are affected by angiogenesis, aiming to provide a broad understanding of how angiogenesis is involved and how microbiota regulate angiogenesis in microbiota-associated human conditions.
- Published
- 2017
39. Abstract 1029: Metastatic cancer cells activate endothelial RhoA-ROCK pathway for trans-endothelial migration
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Sanjay K. Srivastava, Jee Hyun Park, Fatema Tuz Zahra, Sanaullah Sajib, Constantinos M. Mikelis, Ulrich Bickel, and Paul Tullar
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Cancer Research ,RHOA ,biology ,business.industry ,Intravasation ,Cancer ,medicine.disease ,Primary tumor ,Extravasation ,Metastasis ,Oncology ,Cell culture ,Cancer cell ,Cancer research ,medicine ,biology.protein ,business - Abstract
Metastasis is the process through which tumor cells disseminate from the primary tumor and colonize in distant parts of the body. Two of the steps in the metastatic process are the trans-migration of cancer cells through the endothelial lining of blood and lymphatic vessels, during entrance (intravasation) and exit (extravasation) from the vascular system. We and others have shown that the endothelial RhoA pathway plays important role in endothelial permeability. Translating these findings in the metastasis context we aim to explore the role of endothelial RhoA signaling pathway on cancer cell trans-endothelial migration and metastasis. In vitro, we have established a quantifiable, highly reproducible, transwell-based, two-cell co-culture model of trans-endothelial migration, where fluorescently-labeled cancer cells transmigrate through an endothelial monolayer. Pharmacological and molecular biology approaches were incorporated to dissect the role of endothelial RhoA signaling pathway. Primary and immortalized endothelial cells were used and cancer cells of both mouse and human origin were tested. In all cases, conditioned media from the cancer cells activated endothelial RhoA. Blockade of the RhoA pathway inhibited cancer cell trans-endothelial migration. In vivo, syngeneic and human cancer cell lines were tested in tail-vein and intra-cardiac models of experimental metastasis. We observed decreased lung metastatic nodules in endothelial-specific RhoA-deficient mice, compared to the littermate controls. Treatment with a clinically-relevant inhibitor of the RhoA pathway, Fasudil, also decreased the metastatic colonization of both human and cancer cells. The above findings demonstrate that the endothelial RhoA pathway has a pivotal role on cancer cell trans-endothelial migration. Citation Format: Md Sanaullah Sajib, Fatema Tuz Zahra, Jee Hyun Park, Paul Tullar, Sanjay K. Srivastava, Ulrich Bickel, Constantinos M Mikelis. Metastatic cancer cells activate endothelial RhoA-ROCK pathway for trans-endothelial migration [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 1029.
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- 2019
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40. GM-CSF therapy in human caspase recruitment domain–containing protein 9 deficiency
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Amy P. Hsu, Christina Gavino, Rebecca A. Drummond, Fatema Tuz Zahra, Constantinos M. Mikelis, L. Joseph Wheat, Muthulekha Swamydas, Mukil Natarajan, Steven M. Holland, Donald C. Vinh, and Michail S. Lionakis
- Subjects
0301 basic medicine ,biology ,business.industry ,Immunology ,biology.organism_classification ,Molecular biology ,Domain (software engineering) ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,Text mining ,biology.protein ,Immunology and Allergy ,Medicine ,business ,Candida albicans ,Caspase ,030215 immunology - Published
- 2018
- Full Text
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