Effect of Physico-Chemical Properties of Nanoparticles on Their Intracellular Uptake

Cellular internalization of inorganic, lipidic and polymeric nanoparticles is of great significance in the quest to develop effective formulations for the treatment of high morbidity rate diseases. Understanding nanoparticle–cell interactions plays a key role in therapeutic interventions, and it continues to be a topic of great interest to both chemists and biologists. The mechanistic evaluation of cellular uptake is quite complex and is continuously being aided by the design of nanocarriers with desired physico-chemical properties. The progress in biomedicine, including enhancing the rate of uptake by the cells, is being made through the development of structure–property relationships in nanoparticles. We summarize here investigations related to transport pathways through active and passive mechanisms, and the role played by physico-chemical properties of nanoparticles, including size, geometry or shape, core-corona structure, surface chemistry, ligand binding and mechanical effects, in influencing intracellular delivery. It is becoming clear that designing nanoparticles with specific surface composition, and engineered physical and mechanical characteristics, can facilitate their internalization more efficiently into the targeted cells, as well as enhance the rate of cellular uptake.

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Graph Neural Networks for Prediction of Fuel Ignition Quality

10.26434/chemrxiv.12280325.v1 ◽

2020 ◽

Author(s):

Artur Schweidtmann ◽

Jan Rittig ◽

Andrea König ◽

Martin Grohe ◽

Alexander Mitsos ◽

...

Keyword(s):

Neural Networks ◽

Octane Number ◽

Molecular Graph ◽

Chemical Properties ◽

Graph Representation ◽

Structure Property ◽

Oxygenated Hydrocarbons ◽

Physico Chemical ◽

Ignition Quality ◽

Graph Neural Networks

<div>Prediction of combustion-related properties of (oxygenated) hydrocarbons is an important and challenging task for which quantitative structure-property relationship (QSPR) models are frequently employed. Recently, a machine learning method, graph neural networks (GNNs), has shown promising results for the prediction of structure-property relationships. GNNs utilize a graph representation of molecules, where atoms correspond to nodes and bonds to edges containing information about the molecular structure. More specifically, GNNs learn physico-chemical properties as a function of the molecular graph in a supervised learning setup using a backpropagation algorithm. This end-to-end learning approach eliminates the need for selection of molecular descriptors or structural groups, as it learns optimal fingerprints through graph convolutions and maps the fingerprints to the physico-chemical properties by deep learning. We develop GNN models for predicting three fuel ignition quality indicators, i.e., the derived cetane number (DCN), the research octane number (RON), and the motor octane number (MON), of oxygenated and non-oxygenated hydrocarbons. In light of limited experimental data in the order of hundreds, we propose a combination of multi-task learning, transfer learning, and ensemble learning. The results show competitive performance of the proposed GNN approach compared to state-of-the-art QSPR models making it a promising field for future research. The prediction tool is available via a web front-end at www.avt.rwth-aachen.de/gnn.</div>

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Chitosan-Nanocellulose Composites for Regenerative Medicine Applications

Current Medicinal Chemistry ◽

10.2174/0929867327666200127152834 ◽

2020 ◽

Vol 27 (28) ◽

pp. 4584-4592 ◽

Cited By ~ 2

Author(s):

Avik Khan ◽

Baobin Wang ◽

Yonghao Ni

Keyword(s):

Regenerative Medicine ◽

Preparation Method ◽

Chemical Properties ◽

Biological Properties ◽

Next Generation ◽

Structure Property ◽

Physico Chemical ◽

Structure Property Relationship ◽

Attractive Candidate ◽

Fundamental Understanding

Regenerative medicine represents an emerging multidisciplinary field that brings together engineering methods and complexity of life sciences into a unified fundamental understanding of structure-property relationship in micro/nano environment to develop the next generation of scaffolds and hydrogels to restore or improve tissue functions. Chitosan has several unique physico-chemical properties that make it a highly desirable polysaccharide for various applications such as, biomedical, food, nutraceutical, agriculture, packaging, coating, etc. However, the utilization of chitosan in regenerative medicine is often limited due to its inadequate mechanical, barrier and thermal properties. Cellulosic nanomaterials (CNs), owing to their exceptional mechanical strength, ease of chemical modification, biocompatibility and favorable interaction with chitosan, represent an attractive candidate for the fabrication of chitosan/ CNs scaffolds and hydrogels. The unique mechanical and biological properties of the chitosan/CNs bio-nanocomposite make them a material of choice for the development of next generation bio-scaffolds and hydrogels for regenerative medicine applications. In this review, we have summarized the preparation method, mechanical properties, morphology, cytotoxicity/ biocompatibility of chitosan/CNs nanocomposites for regenerative medicine applications, which comprises tissue engineering and wound dressing applications.

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Size and surface modification of silica nanoparticles affect the severity of lung toxicity by modulating endosomal ROS generation in macrophages

Particle and Fibre Toxicology ◽

10.1186/s12989-021-00415-0 ◽

2021 ◽

Vol 18 (1) ◽

Author(s):

Masahide Inoue ◽

Koji Sakamoto ◽

Atsushi Suzuki ◽

Shinya Nakai ◽

Akira Ando ◽

...

Keyword(s):

Immune Response ◽

Surface Modification ◽

Lung Injury ◽

Cellular Uptake ◽

Intratracheal Instillation ◽

Chemical Properties ◽

Raw264.7 Cells ◽

Neutrophilic Infiltration ◽

Silica Nanomaterials ◽

Physico Chemical

Abstract Background As the application of silica nanomaterials continues to expand, increasing chances of its exposure to the human body and potential harm are anticipated. Although the toxicity of silica nanomaterials is assumed to be affected by their physio-chemical properties, including size and surface functionalization, its molecular mechanisms remain unclear. We hypothesized that analysis of intracellular localization of the particles and subsequent intracellular signaling could reveal a novel determinant of inflammatory response against silica particles with different physico-chemical properties. Results We employed a murine intratracheal instillation model of amorphous silica nanoparticles (NPs) exposure to compare their in vivo toxicities in the respiratory system. Pristine silica-NPs of 50 nm diameters (50 nm-plain) induced airway-centered lung injury with marked neutrophilic infiltration. By contrast, instillation of pristine silica particles of a larger diameter (3 μm; 3 μm-plain) significantly reduced the severity of lung injury and neutrophilic infiltration, possibly through attenuated induction of neutrophil chemotactic chemokines including MIP2. Ex vivo analysis of alveolar macrophages as well as in vitro assessment using RAW264.7 cells revealed a remarkably lower cellular uptake of 3 μm-plain particles compared with 50 nm-plain, which is assumed to be the underlying mechanism of attenuated immune response. The severity of lung injury and neutrophilic infiltration was also significantly reduced after intratracheal instillation of silica NPs with an amine surface modification (50 nm-NH2) when compared with 50 nm-plain. Despite unchanged efficacy in cellular uptake, treatment with 50 nm-NH2 induced a significantly attenuated immune response in RAW264.7 cells. Assessment of intracellular redox signaling revealed increased reactive oxygen species (ROS) in endosomal compartments of RAW264.7 cells treated with 50 nm-plain when compared with vehicle-treated control. In contrast, augmentation of endosomal ROS signals in cells treated with 50 nm-NH2 was significantly lower. Moreover, selective inhibition of NADPH oxidase 2 (NOX2) was sufficient to inhibit endosomal ROS bursts and induction of chemokine expressions in cells treated with silica NPs, suggesting the central role of endosomal ROS generated by NOX2 in the regulation of the inflammatory response in macrophages that endocytosed silica NPs. Conclusions Our murine model suggested that the pulmonary toxicity of silica NPs depended on their physico-chemical properties through distinct mechanisms. Cellular uptake of larger particles by macrophages decreased, while surface amine modification modulated endosomal ROS signaling via NOX2, both of which are assumed to be involved in mitigating immune response in macrophages and resulting lung injury.

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Surveillance of influenza A H1N1 2009 among school children during 2009 and 2010 in São Paulo, Brazil

Revista da Sociedade Brasileira de Medicina Tropical ◽

10.1590/s0037-86822012000500005 ◽

2012 ◽

Vol 45 (5) ◽

pp. 563-566 ◽

Cited By ~ 3

Author(s):

Sandra Baltazar Guatura ◽

Aripuana Sakurada Aranha Watanabe ◽

Clarice Neves Camargo ◽

Ana Maria Passos ◽

Sheila Negrini Parmezan ◽

...

Keyword(s):

School Children ◽

Influenza A ◽

Respiratory Infections ◽

Vaccination Campaign ◽

Sao Paulo ◽

Morbidity Rate ◽

High Morbidity ◽

São Paulo ◽

High Morbidity Rate ◽

Influenza A H1n1

INTRODUCTION: Influenza A H1N1 2009 is associated with a high morbidity rate among children around the world, including Brazil. This survey was conducted on samples of symptomatic children (< 12 years) to investigate the influenza virus as the etiological agent of respiratory infections in a day care school in a health facility during the first and second pandemic wave of H1N1 (2009-2010) in São Paulo, Brazil. METHODS: Influenza infections were determined by real-time PCR in 34% (47/137) of children with a median age of 5 years (8 months - 12 years), from June to October 2009 and in 16% (14/85) of those with median age of 6 years (1-12 years), from March to November 2010. RESULTS: In general, most positive cases (64%) occurred in children aged 5-12 years, this age group was significantly the most affected (39.8%, p = 0.001, OR = 8.3, CI 95% 1.9-36.9). Wheezing was reported by 31% (19/61) and dyspnea by 23% (14/61) of the studied patients. An outbreak of influenza H1N1 with an attack rate of 35.7% among children (median age 6 years) was documented in April 2010, before the vaccination campaign against the pandemic virus was extended for children up to 5 years in Brazil. CONCLUSIONS: Therefore, the study reinforces the recommendation to immunize school children to reduce the incidence of the disease.

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Physical Chemistry of the Interface between Attached Micro-Organisms and Their Support

Water Science & Technology ◽

10.2166/wst.1990.0131 ◽

1990 ◽

Vol 22 (1-2) ◽

pp. 1-16 ◽

Cited By ~ 47

Author(s):

P. G. Rouxhet ◽

N. Mozes

Keyword(s):

Photoelectron Spectroscopy ◽

Bacterial Adhesion ◽

Surface Composition ◽

Chemical Properties ◽

Dlvo Theory ◽

Support Surface ◽

X Ray ◽

Polymer Molecules ◽

Physico Chemical ◽

Micro Organisms

The thermodynamic approach of adhesion and DLVO theory are complementary to predict initial bacterial adhesion; the interplay between short- and long-range forces, respectively, may be due to surface roughness. Due to the influence of electrical double layer interactions, adhesion can be promoted by treatments leading to modification of the cell or support surface properties. Adhesion is influenced by cell-cell interactions, by the cpresence of polymer molecules on the surface and by the composition of the medium. X-ray photoelectron spectroscopy can be applied to determine the elemental composition of the surface of microorganisms; some information on the chemical functions can also be obtained. The surface composition is related to physico-chemical properties which play a determining role in adhesion and flocculation, in particular the hydrophobicity and the zeta potential.

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Unsafe abortion among secondary school girls in a local authority in South-South Nigeria

International Journal of Reproduction Contraception Obstetrics and Gynecology ◽

10.18203/2320-1770.ijrcog20203826 ◽

2020 ◽

Vol 9 (9) ◽

pp. 3547

Author(s):

Matthias G. Abah ◽

Emem E. Bassey ◽

Emmanuel B. Edu ◽

Okupa D. Ovie

Keyword(s):

Secondary School ◽

Sex Education ◽

Unwanted Pregnancy ◽

Morbidity Rate ◽

High Morbidity ◽

School Students ◽

Cross Sectional ◽

Level Of Education ◽

Dilation And Curettage ◽

High Morbidity Rate

Background: Voluntary abortion for social reasons is illegal in Nigeria; however, the practice remains mostly clandestine and unsafe with varying consequences and determinants yet to be studied in all settings.Methods: A descriptive cross-sectional study design was used to assess the prevalence, practice and determinants of termination of pregnancy amongst 119 female Secondary School students in South-South Nigeria.Results: The prevalence of abortion was 57.1%. Most of the students were above 18years (58.8%), Christian (95.8%) and of rural residence (66.4%). While 58.8% had experienced an unwanted pregnancy, 61.4% had used some form of contraceptive with condom being the commonest (39.5%). Most (89.1%) have heard of abortions while 67.6% and 16.2% have had abortions once and twice respectively with the top reasons for abortion being that they were still in school (33.8%), too young (25.9%) and to avoid shame or stigma associated with the pregnancy (11.7%). Dilation and curettage was the predominant method employed (40.2%) mainly by medical doctors (34.1% and pharmacists (35.6%) while 51 (75%) had post-abortal complaints such as pain (41.2%) and bleeding (21.6%). There was a significant association between having an abortion and place of residence (rural more than urban), (p=0.04), being pregnant more than once (p<0.001), mothers` level of education (p=0.03), fathers` level of education (p=0.02) and mothers occupation (p=0.04).Conclusions: The prevalence of abortion is high and complicated by high morbidity rate despite a higher contraceptive prevalence rate whose major determinants were the socio-demographic characteristics of the parents. There is a need for early sex education from parents as this can influence abortion perception and practice in later years.

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Monoclonal Antibodies in Multiple Sclerosis: Present and Future

Biomedicines ◽

10.3390/biomedicines7010020 ◽

2019 ◽

Vol 7 (1) ◽

pp. 20 ◽

Cited By ~ 6

Author(s):

Natalia Voge ◽

Enrique Alvarez

Keyword(s):

Multiple Sclerosis ◽

Monoclonal Antibodies ◽

Morbidity Rate ◽

High Morbidity ◽

Disease Modifying Therapies ◽

High Morbidity Rate ◽

New Treatments ◽

Near Future ◽

Risk Ratios

The global incidence of multiple sclerosis (MS) appears to be increasing. Although it may not be associated with a high mortality rate, this disease has a high morbidity rate which affects the quality of life of patients and reduces their ability to do their activities of daily living. Thankfully, the development of novel disease modifying therapies continues to increase. Monoclonal antibodies (MABs) have become a mainstay of MS treatment and they are likely to continue to be developed for the treatment of this disease. Specifically, MABs have proven to be some of the most efficacious treatments at reducing relapses and the inflammation in MS patients, including the first treatment for primary progressive MS and are being explored as reparative/remyelinating agents as well. These relatively new treatments will be reviewed here to help evaluate their efficacy, adverse events, immunogenicity, and benefit-risk ratios in the treatment of the diverse spectrum of MS. The focus will be on MABs that are currently approved or may be approved in the near future.

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The Population Pharmacokinetics of Rifampicin in Japanese Pulmonary Tuberculosis Patients

Drug Research ◽

10.1055/a-1122-8129 ◽

2020 ◽

Vol 70 (05) ◽

pp. 199-205

Author(s):

Takahiro Nishimura ◽

Haruichi Kohno ◽

Hideaki Nagai ◽

Daisuke Maruoka ◽

Yuichi Koike ◽

...

Keyword(s):

Population Pharmacokinetics ◽

Japanese Patients ◽

Morbidity Rate ◽

Pharmacokinetic Parameters ◽

Population Pharmacokinetic ◽

High Morbidity ◽

Power Model ◽

Time Data ◽

Nonlinear Mixed Effects Model ◽

High Morbidity Rate

AbstractIn Japan, tuberculosis has been recognized as one of the major infections requiring urgent measures because of its high morbidity rate even now especially in elderly people suffering from tuberculosis during the past epidemic and its reactivation. Hence, many Japanese clinicians have made efforts to suppress the onset of tuberculosis and treat it effectively. The objectives of this study are to (1) identify covariate(s) that may explain the variation of rifampicin, which is the key antitubercular agent, under the steady-state by evaluating its population pharmacokinetics and (2) to propose an appropriate dosing method of rifampicin to Japanese patients. For this purpose, serum concentration–time data were obtained from 138 patients receiving rifampicin (300–450 mg) and isoniazid (300–400 mg) every day over 14 days, and analyzed using nonlinear mixed effects model. Thereby, population pharmacokinetic parameters were estimated followed by elucidating relations between the parameters and statistical factors. The analysis adopted one-compartment model including Lag-time by assuming that the absorption process is 0+1st order. The analyses demonstrate that meal affected the bioavailability, primary absorption rate constant, and zero order absorption time in the constructed model. A body weight calculated from the power model was selected as the covariate by the Stepwise Covariate Model method and found to highly affect the clearance in the range from −31.6% to 47.4%. We conclude that the dose in Japanese tuberculous patients can be well estimated by the power model formula and should be taken into consideration when rifampicin is administered.

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High morbidity rate after converted laparoscopic colorectal surgery

British Journal of Surgery ◽

10.1002/bjs.1800821036 ◽

1995 ◽

Vol 82 (10) ◽

pp. 1406-1408 ◽

Cited By ~ 78

Author(s):

K. Slim ◽

D. Pezet ◽

Y. Riff ◽

E. Clark ◽

J. Chipponi

Keyword(s):

Colorectal Surgery ◽

Laparoscopic Colorectal Surgery ◽

Morbidity Rate ◽

High Morbidity ◽

High Morbidity Rate

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Analysis Of Heart Decrease In Hypertension Patients With Karotis Artery Massage

Comprehensive Health Care ◽

10.37362/jch.v1i2.213 ◽

2017 ◽

Vol 1 (2) ◽

pp. 1-5

Author(s):

Asnidar ◽

Tenriwati

Keyword(s):

Public Health ◽

Heart Rate ◽

Carotid Artery ◽

Health Center ◽

Sampling Technique ◽

Morbidity Rate ◽

High Heart Rate ◽

High Morbidity ◽

Public Health Center ◽

High Morbidity Rate

Hypertension is a disease that causes a high morbidity rate. The purpose of this study was to analyze the decrease in heart rate of hypertensive patients before and after doing massage on the carotid artery at the Bontobangun Public Health Center. design with population and sample that is all hypertension patients in Public Health Center of Bonto Public Health Center as many as 30 people. The sampling technique used was accidentaly sampling. The results of this study were in the pre-test there were 17 people (56.7%) who were in the category of moderate heart rate, 13 people (43.3%) high heart rate, in the post-test there were 25 people (83.3%) who had moderate heart rate , and 5 people (16.7%) had high heart rates. The conclusion of this study is that there is a decrease in heart rate of hypertension patients after carotid artery massage in public polyclinic public clinics at Bonto Wake with a value of p = 0.008 <α = 0.05. suggestions from this study are so that the results of this study can add a reference regarding carotid artery massage to decrease heart rate in patients with hypertension in the general poly bontobangun puskesmas.

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