Gene Transfer into the Lung by Nanoparticle Dextran-Spermine/Plasmid DNA Complexes

A novel cationic polymer, dextran-spermine (D-SPM), has been found to mediate gene expression in a wide variety of cell lines and in vivo through systemic delivery. Here, we extended the observations by determining the optimal conditions for gene expression of D-SPM/plasmid DNA (D-SPM/pDNA) in cell lines and in the lungs of BALB/c mice via instillation delivery. In vitro studies showed that D-SPM could partially protect pDNA from degradation by nuclease and exhibited optimal gene transfer efficiency at D-SPM to pDNA weight-mixing ratio of 12. In the lungs of mice, the levels of gene expression generated by D-SPM/pDNA are highly dependent on the weight-mixing ratio of D-SPM to pDNA, amount of pDNA in the complex, and the assay time postdelivery. Readministration of the complex at day 1 following the first dosing showed no significant effect on the retention and duration of gene expression. The study also showed that there was a clear trend of increasing size of the complexes as the amount of pDNA was increased, where the sizes of the D-SPM/pDNA complexes were within the nanometer range

Predictive factors of Quality of Life in older adults during the COVID-19 pandemic

Background: Given the vulnerability of older people to COVID-19, it is important to consider their physical and mental wellbeing and quality of life (QoL) in the COVID-19 pandemic. Therefore, the present study was aimed to identify the QoL and its predictive factors among a sample of Iranian older adults during the COVID-19 pandemic. Methods: This descriptive and cross-sectional study was conducted on 500 older people residing in Qazvin, Iran, from May 22th to November 21rd, 2021. Multistage cluster sampling method was used for selecting the eligible older adults. Data were collected using the demographic checklist, fear of COVID-19 scale, and Elderly Quality of Life Questionnaire (LIPAD). The multivariate regression model was used for determining the predictive factors of QoL in older people. Results: The mean age of older participants was 69.17±6.75 years old. The results of multivariate regression model showed that fear of COVID-19, age, marital status, level of education, living arrangement, and economic situation were the signifcant predictors of QoL in the older adults during the COVID-19 pandemic. Conclusions: It is recommended to pay close attention to divorced, lonely, and illiterate older people and those with low economic situation during the COVID-19 pandemic. Keywords: Aged, Quality of life, COVID-19, Fea

Safety profile of dextran-spermine gene delivery vector in mouse lungs

A nano-sized polymer, dextran-spermine (D-SPM), was shown to have the capacity to deliver gene to the lung of mouse via intranasal route. In this study, assessments on the safety profile of D-SPM were performed to complement the gene expression results. African green monkey kidney fibroblast (COS-7) and human adenocarcinoma breast (MCF-7) cells transfected with D-SPM/pDNA showed massive reduction in the number of viable cells. As for in vivo study, elevated level of neutrophils was observed, despite the minimal level of pro-inflammatory cytokines (TNF-α, IL-12, IFN-γ detected in the bronchoalveolar lavage fluid (BALF) of mice treated with the D-SPM/pDNA complexes. Histology profile examinations of the lungs showed mild inflammatory responses, with inflamed areas overlap with healthy areas. Although reduction of mice weight was seen at day 1 post administration, the mice did not show any sign of abnormal behavior or physical appearance. Biodistribution study was performed to determine the ability of the D-SPM/pDNA complexes to infiltrate to other non-intended organs. The result showed that the D-SPM/pDNA complexes were only localized at the lung and no gene expression was detected in other organs or blood. In short, these results indicate that the D-SPM/pDNA exhibited mild toxicity in the mouse lungs

Nanostructure thin Films of titanium dioxide coated on glass and its anti UV effect for living organisms

Abstract: The increasing use of ultraviolet (UV) light in medicine, industrial environments, for cosmetic use, and even in consumer products necessitates that greater attention be paid to the potential hazards of this type of electromagnetic radiation. To avoid any adverse effects of exposure to this type of radiation, suitable protection filters were produced to block UV bands. Nanostructure composite and thin film of titanium dioxide coatings on glass have been prepared by the sol-gel method. TiO2 sol suspension was prepared by first adding titanium tetra isopropoxide (Ti(OPr)4 or TTP) to a mixture of ethanol and HCl (molar ratio TTP:HCl:EtOH:H2O = 1:1.1:10:10) and then adding a 2 wt.% solution of hydroxyl ethyl cellulose (HEC) as dispersant followed by of stirring. Precalcined TiO2 nanopowder was mixed with a sol and heat treated. Thin and composite films were deposited on the glass substrate (microscope glass slide) by spincoating them at ambient conditions. After drying, samples were heated to 500 ºC. The resulting films were characterized by UV-Vis spectroscopy, X-ray diffraction (XRD) and Atomic Force Microscopy (AFM). The purpose of our study was to determine if thin and composite TiO2 films with ultraviolet light have any effect on the growth of Escherichia coli (E. coli), Staphylococcus aureus (S. aureus) and Bacillus species (Bacillus sp.) We have seen unusual results in which TiO2 thin and composite films protect E. coli, S. aureus and Bacillus sp from UV light. The survival of E. coli with UV alone was 3.2 % while with UV and TiO2 composite film was 91%. The UVabsorbing coatings are transparent, colorless, and exhibit high optical quality. The UV-protective coatings offer an easy method to protect the living organisms against UV

In vitro intracellular trafficking of biodegradable nanoparticles dextran spermine in cancer cell lines.

The objective of the present study is to evaluate the effect of cationic dextran on the proliferation rate and biosynthetic activities of HT29, a human colonic adenocarcinoma, and MCF7, a human breast cancer cell line. Cationic dextran was prepared by means of reductive-amination between oxidised dextran and the natural oligoamine, spermine. Biological evaluations including cell proliferation assay, and cell cycle were studied. Flow cytometery was performed in order to determine the biological behaviour of cationic dextran after internalised into the cells. Our results clearly indicated that the cationic dextran was not toxic to the cells when the concentration was 5 μg/ml or lower. The results of the cell cycle flow cytometery indicated that the means of R2 in HT29, MCF7 and HeLa cells were less than 5 three days after treatment with 5 μg/ml of cationic dextran. We conclude that the toxicity of cationic dextran is dose dependent and it is not toxic at concentration lower than 5 μg/ml, and tolerable by the cells, and it can be used as a tool for gene delivery

Dynamics of PEGylated-dextran-spermine nanoparticles for gene delivery to leukemic cells.

Leukemic cells are hard-to-transfect cell lines. Many transfection reagents which can provide high gene transfer efficiency in common adherent cell lines are not effective to transfect established blood cell lines or primary leukemic cells. This study aims to examine a new class of cationic polymer non-viral vector, PEGylated-dextran-spermine (PEG-D-SPM), to determine its ability to transfect the leukemic cells. Here, the optimal conditions of the complex preparation (PEG-D-SPM/plasmid DNA (pDNA)) were examined. Different weight-mixing (w/w) ratios of PEG-D-SPM/pDNA complex were prepared to obtain an ideal mixing ratio to protect encapsulated pDNA from DNase degradation and to determine the optimal transfection efficiency of the complex. Strong complexation between polymer and pDNA in agarose gel electrophoresis and protection of pDNA from DNase were detected at ratios from 25 to 15. Highest gene expression was detected at w/w ratio of 18 in HL60 and K562 cells. However, gene expression from both leukemic cell lines was lower than the control MCF-7 cells. The cytotoxicity of PEG-D-SPM/pDNA complex at the most optimal mixing ratios was tested in HL60 and K562 cells using MTS assay and the results showed that the PEG-D-SPM/pDNA complex had no cytotoxic effect on these cell lines. Spherical shape and nano-nature of PEG-D-SPM/pDNA complex at ratio 18 was observed using transmission electron microscopy. As PEG-D-SPM showed modest transfection efficiency in the leukemic cell lines, we conclude that further work is needed to improve the delivery efficiency of the PEG-D-SPM

Toxicity evaluation of dextran-spermine polycation as a tool for genetherapy in vitro.

Cationic polymers are a leading class of nonviral self-assembled nucleic acid delivery systems. Cationic polymers have been shown to condence the DNA so that the entrapped DNA is protected from contact with DNase. The objective of the present study is to evaluate the effect of cationic dextran on the proliferation rate, morphological changes and biosynthetic activities in vitro. Cationic dextran was prepared by means of reductive-amination between oxidized dextran and the natural oligoamine, spermine. Four kinds of biological evaluations including cell proliferation assay, ultrastructural changes of cells using transmission electron microscopy (TEM), acridine orange/Propidium Iodide and cell cycle were studied. Our results clearly indicated that the toxicity of cationic dextran is dose depended and it is not toxic at low concentration and tolerable by the cells, and it can be used as a tool for gene delivery

Minimal information for studies of extracellular vesicles 2018 (MISEV2018):a position statement of the International Society for Extracellular Vesicles and update of the MISEV2014 guidelines

The last decade has seen a sharp increase in the number of scientific publications describing physiological and pathological functions of extracellular vesicles (EVs), a collective term covering various subtypes of cell-released, membranous structures, called exosomes, microvesicles, microparticles, ectosomes, oncosomes, apoptotic bodies, and many other names. However, specific issues arise when working with these entities, whose size and amount often make them difficult to obtain as relatively pure preparations, and to characterize properly. The International Society for Extracellular Vesicles (ISEV) proposed Minimal Information for Studies of Extracellular Vesicles (“MISEV”) guidelines for the field in 2014. We now update these “MISEV2014” guidelines based on evolution of the collective knowledge in the last four years. An important point to consider is that ascribing a specific function to EVs in general, or to subtypes of EVs, requires reporting of specific information beyond mere description of function in a crude, potentially contaminated, and heterogeneous preparation. For example, claims that exosomes are endowed with exquisite and specific activities remain difficult to support experimentally, given our still limited knowledge of their specific molecular machineries of biogenesis and release, as compared with other biophysically similar EVs. The MISEV2018 guidelines include tables and outlines of suggested protocols and steps to follow to document specific EV-associated functional activities. Finally, a checklist is provided with summaries of key points