scholarly journals Electrostatic Surface Properties of Blood and Semen Extracellular Vesicles: Implications of Sialylation and HIV-Induced Changes on EV Internalization

Viruses ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 1117
Author(s):  
Hussein Kaddour ◽  
Tyler D. Panzner ◽  
Jennifer L. Welch ◽  
Nadia Shouman ◽  
Mahesh Mohan ◽  
...  
Keyword(s):  
Surface Charge ◽  
Critical Role ◽  
Substantial Reduction ◽  
Extracellular Vesicle ◽  
Peripheral Blood Lymphocytes ◽  
Epithelial Cell Line ◽  
P Value ◽  
Neuraminidase Treatment ◽  
Ζ Potential ◽  
Electrostatic Properties

Although extracellular vesicle (EV) surface electrostatic properties (measured as zeta potential, ζ-potential) have been reported by many investigators, the biophysical implications of charge and EV origin remains uncertain. Here, we compared the ζ-potential of human blood EVs (BEVs) and semen EVs (SEVs) from 26 donors that were HIV-infected (HIV+, n = 13) or HIV uninfected (HIV-, n = 13). We found that, compared to BEVs that bear neutral surface charge, SEVs were significantly more negatively charged, even when BEVs and SEVs were from the same individual. Comparison of BEVs and SEVs from HIV- and HIV+ groups revealed subtle HIV-induced alteration in the ζ-potential of EVs, with the effect being more significant in SEVs (∆ζ-potential = −8.82 mV, p-value = 0.0062) than BEVs (∆ζ-potential = −1.4 mV, p-value = 0.0462). These observations were validated by differences in the isoelectric point (IEP) of EVs, which was in the order of HIV + SEV ≤ HIV-SEV ≪ HIV + BEV ≤ HIV-BEV. Functionally, the rate and efficiency of SEV internalization by the human cervical epithelial cell line, primary peripheral blood lymphocytes, and primary blood-derived monocytes were significantly higher than those of BEVs. Mechanistically, removal of sialic acids from the surface of EVs using neuraminidase treatment significantly decreased SEV’s surface charge, concomitant with a substantial reduction in SEV’s internalization. The neuraminidase effect was independent of HIV infection and insignificant for BEVs. Finally, these results were corroborated by enrichment of glycoproteins in SEVs versus BEVs. Taken together, these findings uncover fundamental tissue-specific differences in surface electrostatic properties of EVs and highlight the critical role of surface charge in EV/target cell interactions.

Abstract P392: The Effect Of Cell Sex On Magnetic Nanoparticle Uptake Of Human Induced Pluripotent Stem Cell-derived Cardiomyocytes

2021 ◽  
Vol 129 (Suppl_1) ◽  
Author(s):  
Morteza Mahmoudi ◽  
Vahid Serpooshan ◽  
Phillip C Yang ◽  
Mahyar Heydarpour
Keyword(s):  
Heart Failure ◽  
Actin Filaments ◽  
Electromechanical Coupling ◽  
Critical Role ◽  
Induced Pluripotent Stem Cell ◽  
Patient Specific ◽  
P Value ◽  
Male And Female ◽  
Cell Therapies ◽  
Human Cardiomyocytes

Introduction: It is well understood that the occurrence, progress, and treatment of heart failure, which is a leading cause of death worldwide, is sex-specific. Over the past decade, the majority of efforts in myocardial regeneration have been centered on cell-based cardiac repair. A promising cell source for these efforts is patient-specific human cardiomyocytes (CMs) differentiated from human inducible pluripotent stem cells (hiPSCs). However, successful use of hiPSC-CMs faces a major limitation, the poor engraftment and electromechanical coupling of transplanted cells with the host myocardial tissue. Magnetic nanoparticles (NPs) demonstrate great potential to address this challenge for treating heart failure via cell therapies. In particular, superparamagnetic iron oxide NPs (SPIONs) have been used to label hiPSC-CMs and, with the aid of external magnetic field, improve their engraftment and electromechanical coupling in the heart tissue. However, the critical role of cell sex in the uptake and labeling efficacy of NPs has not been evaluated. Hypothesis: Significant differences in the molecular and structural (e.g., actin structures and distribution) characteristics of male and female hiPSC-CMs affect their labeling efficacy with SPIONs. Methods and Results: To test our hypothesis, we first performed RNA-Seq analysis on three male and three female (healthy) hiPSC-CM lines. The normalized outcomes were analyzed by edgeR package. We next calculated gene-expression differential between male and female CMs. The results revealed 58 genes with significant differences between the male and female cells (p-value < 0.01). The highest observed sex-specific variation in genes was related to tophit gene (MEG3: logFC = 7.32, P-value = 5.63e -06 ), which is the maternally expressed imprinted gene with a great role in cardiac angiogenesis. Among the identified genes, a number of those were related to the cellular cytoskeletal structures including actin. We probed possible structural differences between actin filaments organization and distribution of male and female hiPSC-CMs using the stochastic optical reconstruction microscopy (STORM) technique. The results demonstrated substantial differences in organization, distribution, and morphology of actin filaments between male and female CMs. Incubation of SPIONs with male and female hiPSC-CMs revealed higher uptake of NPs (~ 3 folds) in female cells as compared to the male cells. The significant differences in the uptake of SPIONs by male vs. female cells could be attributed to the distinct organization, distribution, and morphology of actin in male vs. female cells. Conclusions: Our results indicate that male and female hiPSCs-CMs respond differently to the labeling SPIONs.

scholarly journals Correlates of Knowledge of HIV Transmission Among Incident Cases of HIV in a Cohort of Injection Drug Users Receiving Harm Reduction Services at Karachi, Pakistan

2014 ◽  
Vol 16 (3) ◽  
pp. 286-289 ◽  
Author(s):  
Rab Nawaz Samo ◽  
Arshad Altaf ◽  
Sharaf Ali Shah
Keyword(s):  
Harm Reduction ◽  
Injection Drug Users ◽  
Drug Users ◽  
Hiv Transmission ◽  
Critical Role ◽  
Unprotected Sex ◽  
Injection Drug ◽  
P Value ◽  
High Risk Population ◽  
Incident Cases

Background: Knowledge of risk factors for HIV transmission in high-risk population plays a critical role in averting the risk of HIV transmission. In Pakistan, injection drug users (IDUs) constitute the core risk group of HIV prevalence, where the epidemic has transitioned to a “concentrated level.” Still nothing is known about the role of knowledge in HIV transmission and HIV sero-conversion among IDUs in Pakistan. Methods: From 2009 to 2011, a nested case–control study was conducted in a cohort of 636 IDUs receiving harm reduction services in the mega city of Karachi. Results: In multivariable regression analysis, 3 factors, namely HIV does not spread through unprotected sex (adjusted odds ratio [AOR]: 3.1, 95% confidence interval [CI] 1.39-6.90, P value .01), HIV does not transmit by sharing syringes (AOR: 3.5, 95% CI 1.97-6.40, P value <.00), and the risk of HIV cannot be minimized by using new syringe every time (AOR: 2.0, 95% CI 1.16-3.60, P value .01), were significantly associated with the incident cases of HIV. Conclusion: The study findings suggest the association between knowledge of HIV transmission and HIV sero-incident cases.

scholarly journals Hypoxic Status Is Associated With The Intensity Of Hypoxia Inducible Factor (Hif)-1α Expression In A Premature Placenta

2021 ◽  
Vol 17 (1) ◽  
pp. 1-11
Author(s):  
Kartini Edwin
Keyword(s):  
Confidence Interval ◽  
Premature Birth ◽  
Odds Ratio ◽  
Critical Role ◽  
Hypoxia Inducible Factor ◽  
Biological Materials ◽  
P Value ◽  
Live Births ◽  
Infant Morbidity ◽  
The Relationship

Prematurity refers to live births before 37 weeks of gestation and associated with infant morbidity/mortality. Activation of HIF during the final pregnancy phase is believed to play a critical role in the pathogenesis of premature birth and other pregnancy disorders. This study aimed to analyze the relationship between hypoxicstatus and the intensity of HIF-1α expression in a premature placenta.Stored biological materials premature placenta (paraffin blocks) was used in this study. Thirtyone samples of placental hypoxia (H) and 28 samples of premature placental non-hypoxia (N) as controls, were selected non-random consecutively. Subsequently, immunohistochemistry was performed to analyze HIF-1α expression. TheChi-square testwas used to analyze the data and a p-value <0.05 was considered statistically significant.Moderate to strong intensity of HIF-1α expressionwas observed in 58% of hypoxic placenta samples, whereas most of non-hypoxic placental samples(86%) did not expressed or expressed weaklyHIF-1α.There was a significant correlation between the intensity of HIF-1α expression and placental hypoxia (p <0.05) and Odds Ratio (OR) value was 8.31 with a 95% confidence interval (2.32-29.77). The conclusion shows that hypoxic status is associated with intensity of hypoxia inducible factor (HIF)-1α expression in a premature placenta.

scholarly journals Advancement of Measurement Techniques for Tunable Resistive Pulse Sensing

2021 ◽  
Author(s):  
◽  
Eva Weatherall
Keyword(s):  
Surface Charge ◽  
Pore Size ◽  
Applied Voltage ◽  
Particle Surface ◽  
Streaming Potential ◽  
Pore Surface ◽  
Size Distributions ◽  
Ζ Potential ◽  
Resistive Pulse ◽  
Tunable Resistive Pulse Sensing

<p>Tunable resistive pulse sensing (TRPS) is a particle-by-particle analysis technique combining the Coulter principle with size-tunable pores. TRPS can be used to characterize biological and synthetic particles 50 nm - 20 µm in diameter. Information is obtained from the resistive pulse signal, a transient change in ionic current observed when a particle passes through the pore. TRPS has been shown to provide excellent resolution and accuracy for measuring particle size and concentration as well as providing information about particle charge. TRPS is therefore applicable to many industrial and fundamental research areas involving aptamers, drug delivery particles, extracellular vesicles and other biological particle types. Advancement of this technology requires a better understanding of the technique, particularly in the area of particle surface charge measurement and this Thesis helps to provide that understanding.  In this work, firstly particle ζ-potential measurement using TRPS was investigated. A number of different measurement methods are presented and the uncertainties associated with each method are outlined. The ζ-potential for a variety of particles with different surface charges were measured in a range of electrolytes.  Particle ζ-potential measurements were then improved upon with the addition of streaming potential measurements to measure the pore surface charge. The ζ-potential of the pore surface, which makes a significant contribution to particle ζ-potential calculations, was measured using a set up which works alongside the qNano. Streaming potential measurements were also used to investigate changes in the pore surface charge following application of number of different chemical coatings. The volume of data collected and detail of analysis in this work (including uncertainties) is unprecedented in TRPS ζ potential measurements.  Biphasic pulses arising from the charge on the particles were investigated. The pulse is conventionally resistive, but biphasic pulses which include both resistive and conductive components are significant for less than 50 mM salt concentrations when measuring 200 nm particles. The experimental variables investigated include the concentration of the electrolyte, particle charge, pore size, applied voltage, and the direction of particlemotion. Conductive pulse size was seen to decrease with increasing electrolyte concentration and pore size and increase with applied voltage. A linear relationship was found between conductive pulse magnitude and particle surface group density. The influence of direction of motion on conductive pulses was consistent with concentration polarization of an ion selective pore. Biphasic pulses were also seen to affect conventional TRPS particle size measurements.  Finally, size distribution broadening due to varying particle trajectories was investigated. Pulse size distributions for monodisperse particles became broader when the pore size was increased and featured two distinct peaks. Relatively large pulses are produced by particles with trajectories passing near to the edge of the pore. Other experiments determined that pulse size distributions are independent of applied voltage but broaden with increasing pressure applied across the membrane.</p>

scholarly journals Sales Territory Design and Salesforce Performance in the Detergent Manufacturing Companies: The Actual Kenyan Context

2021 ◽  
Vol 17 (35) ◽  
pp. 203
Author(s):  
Benson Muchoki Mwangi ◽  
Francis N. Kibera ◽  
Mary Kinoti ◽  
Magutu P. Obara
Keyword(s):  
Critical Role ◽  
Strong Relationship ◽  
Primary Data ◽  
P Value ◽  
Manufacturing Companies ◽  
Cross Sectional ◽  
Territory Design ◽  
Simple Regression Model ◽  
Independent Variable ◽  
Cross Sectional Design

This paper focuses on determining the influence of sales territory design on salesforce performance in the detergent manufacturing companies in Kenya. Detergents play a critical role in our everyday lives by ensuring hygiene at our personal level, in our homes, in schools, institutions, and hospitals. Detergents have gained a lot of prominence since the onset of the Corona Virus (COVID-19) disease in 2019, as it has been proved that they play an important role in curtailing the transmission of the COVID-19 disease. The Salesforce plays an important role in organizations as they are the ones who in most cases interact with customers, provide information about their organization and products, provide prices, demonstrate how products are used, train customers, provide after sales service, and resolve any issues that may arise. The study was anchored on Expectancy Theory, Resource Based Theory, Equity Theory, and Agency Theory. The study adopted positivism philosophy and used a descriptive cross sectional design. The unit of analysis was the sales people in the detergent manufacturing companies in Kenya who are members of Kenya Association of Manufacturers as per list obtained from KAM in December 2018. The study used primary data which was collected by administering semi-structured questionnaires. The data was analyzed using a combination of both descriptive and inferential statics to describe the manifestations of the variables in the data collected, simple regression model was used to test the significance of the influence of sales territory design (independent variable) on the salesforce performance (dependent variable). Fischer distribution test (F-test) was used to test the significance of the independent variable and the overall model. The p-value for the F-statistic was used to determine the robustness of the model. This was done at 95% confidence level (p<0.05). The study found a strong relationship between sales territory design and salesforce performance. This depicts that sales territory design is critical in determining salesforce performance in detergent manufacturing companies in Kenya.

Abstract 361: Neuregulin Transcriptional Programming of Embryonic Endothelial Progenitor Cells and Embryonic Stem Cells

2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Jijun Hao ◽  
Cristi L Galindo ◽  
Radwan N Safa ◽  
Truc-Linh Tran ◽  
Douglas B Sawyer
Keyword(s):  
Stem Cells ◽  
Embryonic Stem Cells ◽  
Heart Development ◽  
Progenitor Cell ◽  
Critical Role ◽  
Embryonic Stem ◽  
Mapk Signaling ◽  
P Value ◽  
Type I ◽  
Endothelial Progenitor

Jijun Hao, Cristi L. Galindo, Radwan N. Safa, Truc-Linh Tran, Douglas B. Sawyer Neuregulin-1 (NRG-1) plays a critical role in heart development by signaling through type I receptor tyrosine kinases in the erbB family (erbB2, erbB3 and erbB4). Mice with disrupted expression of NRG-1, ErbB2, ErbB3 or ErbB4 die in utero with failure of cardiac development. We have previously shown that NRG-1 has distinct effects on two embryonic progenitor cell populations that express ErbB2 and ErbB3 receptors. In an embryonic endothelial progenitor cell line (eEPCs) NRG-1 treatment induces phosphorylation of Akt, GSK-3β, and Erk1/2, and protects eEPCs against serum deprivation-induced apoptosis. In embryonic stem cells (ESCs) we find that NRG-1 treatment from day 0∼2 induces cardiomyocyte formation by day 8 in culture, and when ErbB3 is knocked down in the ESCs, NRG-1 fails to promote cardiomyogenesis. To understand early molecular events that might regulate these distinct effects, we analyzed global transcriptional changes induced by NRG-1 in both eEPCs and ESCs using microarrays. There were only 244 significantly differential (p value < 0.05, fold-change > 1.5) genes detected in NRG-1-treated ESCs, while NRG-1 induced differential expression of 1,547 transcripts in eEPCs. Based on functional analysis, the most significantly over-represented function (Fishers Exact Test, p value with FDR < 0.05) in ESCs was “cell morphogenesis during differentiation”. In eEPCs, genes regulated via Ras/MAPK signaling were altered, as were those downstream of the Akt-PI3K pathway and calcium signaling. For both cell lines, the most statistically significant transcription factor identified as a regulator of the genes altered in response to NRG-1 was SRF, consistent with a role for NRG-1 in heart development and regeneration. Based on the results of this study, we constructed a putative signaling pathway whereby NRG mediates cardiomyogenesis in pluripotent stem cells that correlates with phenotypic observations.

scholarly journals SMOKING GENOTOXICITY IN PERIPHERAL BLOOD LYMPHOCYTES USING THE COMET ASSAY

2013 ◽  
Vol 03 (03) ◽  
pp. 038-041
Author(s):  
Shobha S. Shetty ◽  
Hrishikesh Nachane
Keyword(s):  
Dna Damage ◽  
Comet Assay ◽  
Peripheral Blood ◽  
Peripheral Blood Lymphocytes ◽  
The Body ◽  
P Value ◽  
Tail Moment ◽  
Blood Lymphocytes ◽  
Significant Difference ◽  
Almost All

Abstract Background: Smoking has been shown to have a positive effect on DNA damage in almost all the cells of the body. Quantitative analysis of this damage will help in assessing the etiopathogenesis of various nicotine induced damage to the body. Comet assay has been an emerging tool in this regard and hence was applied by us to estimate the severity of DNA damage in smokers. Aims & Objectives: To evaluate the DNA genotoxicity in peripheral blood lymphocytes in smokers and their comparison with non smokers & assess the quantitative damage. Materials and methods: 30 smokers & 20 non smokers were recruited & their peripheral blood was taken for the comet assay to look for Olive moment & Tail moment to quantitatively assess the DNA damage due to cigarette smoking. Results: In our study there was no significant difference in the analysis of DNA damage (with regard to tail moment & olive moment) in smokers versus non smokers (P value: more than 0.05). Conclusions: Though smoking is known to cause DNA damage, we did not find significant differences between the two groups probably due to other multifactorial etiologies for genotoxicity.

scholarly journals Adaptive lighting comfort in the classrooms of educational building and student hostel rooms

2020 ◽  
Vol 170 ◽  
pp. 01012
Author(s):  
Subbarao Yarramsetty ◽  
Nikhil Siva Deka ◽  
MVN Siva Kumar
Keyword(s):  
Classroom Environment ◽  
Indoor Environment ◽  
Critical Role ◽  
Comfort Level ◽  
P Value ◽  
Lighting Intensity ◽  
Institute Of Technology ◽  
Teaching Learning ◽  
Indoor Lighting ◽  
The Impact

The comfort level of occupants inside a building depends on various indoor environment factors like thermal comfort, indoor air quality, and indoor lighting quality. According to studies done on indoor environment quality of buildings, lighting plays a very critical role in determining the occupants comfort level. A proper indoor lighting is very important especially in the classrooms of an educational building as well as in student hostel rooms as it can be said as a vital element, controlling the psychology and comfort of the students and hence a deciding factor in the teaching-learning process. The lighting intensity and its distribution depends on the location of the interior partition as well as the design strategy of the exterior envelop. So, in order to obtain the most occupant friendly results, the impact of various strategies adopted should be evaluated in the early design period itself. This paper adopts a questionnaire-based field surveys which is done in the classrooms of National Institute of Technology Warangal and also in the hostel rooms of 1.8K Ultra Mega hostel of this institute. The main objective of this study includes. 1) To assess the indoor lighting comfort in the classrooms and hostel rooms of National Institute of Technology Warangal through a questionnaire-based lighting comfort study. 2) To identify preferences of subjects in the classroom environment with respect to lighting comfort and 3) To identify the comfort range of lighting intensity inside the classrooms and hostel rooms. SPSS software is used analyse the reliability of survey responses by finding the P value.

scholarly journals Guanylate Binding Proteins Restrict Leishmania donovani Growth in Nonphagocytic Cells Independent of Parasitophorous Vacuolar Targeting

mBio ◽  
2020 ◽  
Vol 11 (4) ◽  
Author(s):  
Arun Kumar Haldar ◽  
Utsav Nigam ◽  
Masahiro Yamamoto ◽  
Jörn Coers ◽  
Neena Goyal
Keyword(s):  
Host Defense ◽  
Leishmania Donovani ◽  
Binding Proteins ◽  
Critical Role ◽  
Intrinsic Property ◽  
Epithelial Cell Line ◽  
Cell Type ◽  
Phagocytic Cells ◽  
Defense Proteins ◽  
Content Type

ABSTRACT Interferon (IFN)-inducible guanylate binding proteins (GBPs) play important roles in host defense against many intracellular pathogens that reside within pathogen-containing vacuoles (PVs). For instance, members of the GBP family translocate to PVs occupied by the protozoan pathogen Toxoplasma and facilitate PV disruption and lytic parasite killing. While the GBP defense program targeting Toxoplasma has been studied in some detail, the role of GBPs in host defense to other protozoan pathogens is poorly characterized. Here, we report a critical role for both mouse and human GBPs in the cell-autonomous immune response against the vector-borne parasite Leishmania donovani. Although L. donovani can infect both phagocytic and nonphagocytic cells, it predominantly replicates inside professional phagocytes. The underlying basis for this cell type tropism is unclear. Here, we demonstrate that GBPs restrict growth of L. donovani in both mouse and human nonphagocytic cells. GBP-mediated restriction of L. donovani replication occurs via a noncanonical pathway that operates independent of detectable translocation of GBPs to L. donovan-containing vacuoles (LCVs). Instead of promoting the lytic destruction of PVs, as reported for GBP-mediated killing of Toxoplasma in phagocytic cells, GBPs facilitate the delivery of L. donovani into autolysosomal-marker-positive compartments in mouse embryonic fibroblasts as well as the human epithelial cell line A549. Together our results show that GBPs control a novel cell-autonomous host defense program, which renders nonphagocytic cells nonpermissible for efficient Leishmania replication. IMPORTANCE The obligate intracellular parasite Leishmania causes the disease leishmaniasis, which is transmitted to mammalian hosts, including humans, via the sandfly vector. Following the bite-induced breach of the skin barrier, Leishmania is known to live and replicate predominantly inside professional phagocytes. Although Leishmania is also able to infect nonphagocytic cells, nonphagocytic cells support limited parasitic replication for unknown reasons. In this study, we show that nonphagocytic cells possess an intrinsic property to restrict Leishmania growth. Our study defines a novel role for a family of host defense proteins, the guanylate binding proteins (GBPs), in antileishmanial immunity. Mechanistically, our data indicate that GBPs facilitate the delivery of Leishmania into antimicrobial autolysosomes, thereby enhancing parasite clearance in nonphagocytic cells. We propose that this GBP-dependent host defense program makes nonphagocytic cells an inhospitable host cell type for Leishmania growth.

The ζ-Potential of Kaolinite Particles

1956 ◽  
Vol 9 (4) ◽  
pp. 450 ◽  
Author(s):  
N Street ◽  
AS Buchanan
Keyword(s):  
Charge Density ◽  
Surface Charge ◽  
Electrophoretic Mobility ◽  
Surface Charge Density ◽  
Considerable Increase ◽  
Ionic Species ◽  
Ζ Potential ◽  
Potentiometric Titrations ◽  
Kaolinite Suspension

Electrophoretic mobility measurements, and both conductometric and potentiometric titrations, were carried out on a kaolinite suspension throughout its neutralization by various bases. The concentration of the ionic species present was calculated from the conductometric and potentiometric titrations, and the true ζ-potential calculated from the electrophoretic mobility by Stigter and Mysels's (1955) method. The results indicate that a discontinuity exists in the adsorption of ions in the vicinity of pH 6.5-7.0 causing a considerable increase in the surface charge density of the particles.

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