N Simiónescu

Romanian Academy

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Maya Simionescu

Romanian Academy

M Scherzer

Charité - Universitätsmedizin Berlin

Anca Roxana Petrovici

Romanian Academy

Anca V. Sima

Romanian Academy

George E. Palade

Universitatea de Medicină, Farmacie, Științe și Tehnologie „George Emil Palade” din Târgu Mureș

Loredan S. Niculescu

Romanian Academy

Mariana Pinteală

Romanian Academy

M Oprescu

Spitalul Clinic Judetean de Urgentã Craiova

Mihail Coculescu

Carol Davila University of Medicine and Pharmacy

A Constantinovici

Clinical Emergency Hospital Bucharest

Cooperative Institutions

Manchester Metropolitan University

133

Romanian Academy

University of Salford

Grigore T. Popa University of Medicine and Pharmacy

Universidad de Granada

Clinical Emergency Hospital Bucharest

Istituti di Ricovero e Cura a Carattere Scientifico

Carol Davila University of Medicine and Pharmacy

Centro Cardiologico Monzino

Institutul de Chimie Macromoleculară Petru Poni

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Microvesicles and Microvesicle-Associated microRNAs Reflect Glioblastoma Regression: Microvesicle-Associated miR-625-5p Has Biomarker Potential

International Journal of Molecular Sciences (2022)

N Simiónescu Miruna Nemecz Anca Roxana Petrovici Ioan Sebastian Nechifor Razvan-Cristian Buga

Glioblastoma (GB) is the most aggressive and recurrent form of brain cancer in adults. We hypothesized that the identification of biomarkers such as certain microRNAs (miRNAs) and the circulating microvesicles (MVs) that transport them could be key to establishing GB progression, recurrence and therapeutic response. For this purpose, circulating MVs were isolated from the plasma of GB patients (before and after surgery) and of healthy subjects and characterized by flow cytometry. OpenArray profiling and the individual quantification of selected miRNAs in plasma and MVs was performed, followed by target genes' prediction and in silico survival analysis. It was found that MVs' parameters (number, EGFRvIII and EpCAM) decreased after the surgical resection of GB tumors, but the inter-patient variability was high. The expression of miR-106b-5p, miR-486-3p, miR-766-3p and miR-30d-5p in GB patients' MVs was restored to control-like levels after surgery: miR-106b-5p, miR-486-3p and miR-766-3p were upregulated, while miR-30d-5p levels were downregulated after surgical resection. MiR-625-5p was only identified in MVs isolated from GB patients before surgery and was not detected in plasma. Target prediction and pathway analysis showed that the selected miRNAs regulate genes involved in cancer pathways, including glioma. In conclusion, miR-625-5p shows potential as a biomarker for GB regression or recurrence, but further in-depth studies are needed.

Microvesicle

10.3390/ijms23158398

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Citations (11)

New Insights on Hemp Oil Enriched in Cannabidiol: Decarboxylation, Antioxidant Properties and In Vitro Anticancer Effect

Anca Roxana Petrovici N Simiónescu Andreea-Isabela Sandu Vasile Paraschiv Mihaela Silion

This study aimed to obtain and characterize extracted hemp oil enriched in cannabidiol (CBD) by decarboxylation of cannabidiolic acid (CBDA) and to give new insights into its antioxidant and anticancer effects. Optimization of CBDA decarboxylation in hemp oil was performed, and CBD and CBDA contents and purities were determined by “flash chromatography”, 1H- and 13C-NMR. The antioxidant properties of CBD-enriched oil were investigated by Fe2+ chelating activity, Fe3+ reducing antioxidant power assay, O2− scavenging activity, HO− scavenging ability and lipid peroxidation inhibitory assay and its cytotoxicity, apoptosis- and oxidative stress-inducing effects on NHDF, MeWo, HeLa, HepG2 and HOS cells were determined. The CBD concentration in hemp oil was increased by CBDA soft decarboxylation optimized at 90°C, for 1 h and resulted oil was capable of reducing iron, scavenging free radicals, and inhibiting lipid peroxidation in cell-free oxidative conditions. CBD-enriched oil promoted NHDF proliferation at up to 15 µg CBD/mL, while inducing apoptosis and ROS production and modulating antioxidant enzymes’ gene expression in cancer cells, being selective for osteosarcoma cells and induced apoptosis by p53- and ROS-independent mechanisms. CBD-enriched hemp oil demonstrated antioxidant properties in oxidative conditions and promoted normal fibroblasts’ proliferation, while inducing apoptosis and ROS production in cancer cells.

10.20944/preprints202103.0346.v1

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Citations (12)

A multidisciplinary approach of the psycho-somatic involution syndrome.

PubMed (1976)

Presdescu Gabriel Constantinescu M Alexianu B Tudorache Ștefan Tudor

Involution (esoterism)

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[The influence of pineal autografts on experimental liver cirrhosis in white rats].

PubMed (1963)

L Vaisler N Simiónescu E Costiner M Goldstein

White (mutation)

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One-Step Preparation of Carboxymethyl Cellulose—Phytic Acid Hydrogels with Potential for Biomedical Applications

Gels (2022)

Alina Ghilan Loredana E. Niţă Daniela Pamfil N Simiónescu Niţǎ Tudorachi

Hydrogels based on natural, biodegradable materials have gained considerable interest in the medical field due to their improved drug delivery profiles and tissue-mimicking architecture. In this regard, this study was devoted to the preparation and characterization of new physically crosslinked hydrogels based on carboxymethyl cellulose and an unconventional crosslinking agent, phytic acid. Phytic acid, in addition to its antioxidant and antibacterial effects, can improve the biological properties and stability of gels, without adding toxicity. Fourier transform infrared (FTIR) spectroscopy, rheological studies and thermal analysis confirmed the hydrogel formation. The influence of the ratio between the cellulose derivative and the crosslinker upon the morphological structure and water uptake was evidenced by scanning electron microscopy (SEM) and swelling measurements in simulated body fluids. Furthermore, procaine was entrapped within the hydrogels and used as a model drug for in vitro studies, which highlighted the dependence of the drug release on the phytic acid content of the matrix. The materials demonstrated antibacterial effects against Escherichia coli and Staphylococcus aureus bacteria. The biocompatibility was assessed on fibroblast cells, and according to our results, hydrogels can improve cell viability highlighting the potential of these systems as therapeutic scaffolds for skin tissue engineering.

Carboxymethyl cellulose

Biocompatibility

Biomaterial

10.3390/gels8100647

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Citations (15)

Purification and partial characterization of extracellular liposomes isolated from the hyperlipidemic rabbit aorta

Journal of Lipid Research (1990)

Rosalia Mora Maya Simionescu N Simiónescu

Extracellular liposomes (EL) that accumulated in the aortic intima of rabbits on 2 weeks (prelesional stage) and 16 weeks (lesional stage) of diet-induced hyperlipidemia were isolated and purified by gel filtration, ultracentrifugation, and affinity chromatography on anti-apoB.andanti-albumin Sepharose.The material obtained after each step was examined by negative staining electron microscopy, by protein analysis (SDS-PAGE, immunoblotting, autoradiography, uronic acid), and by lipid analysis for unesterified cholesterol (UC), cholesteryl esters (CE), phospholipids (PL), triglycerides (E), thiobarbituric acid reactants (TBAR).EL represented the major constituent of intimal lipid deposits; their predominance on particulate betalipoproteins (LP) increased with the duration of hyperlipoproteinemia.As compared with serum low density lipoproteins (LDL) and beta-very low density lipoproteins (beta-VLDL), the crude EL fraction obtained after gel filtration and ultracentrifugation had a decrease in CE and TG, with augmentation of UC, PL, and apoB.After removal of apoB and some albumin by immunoadsorption, the purified EL fraction consisted only of UC, PL, and albumin.The albumin was resistant to proteolytic digestion with pronase, and reacted with anti-albumin antibody only after delipidation of EL.This indicated that albumin was trapped in the aqueous core of vesicles, presumably acting as a scavenger of oxygen-free radicals.TBAR was highly associated with intact or degraded beta-LP.I The EL that accumulate in the aortic intima of hyperlipidemic rabbits represent the predominant form of lipid deposits, resulting from the transcytosed excess beta-LP, which is degraded and reassembled upon interaction with the extracellular matrix components.-Mora,

10.1016/s0022-2275(20)42323-5

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Citations (24)

Binding of vascular anticoagulant alpha (annexin V) to the aortic intima of the hypercholesterolemic rabbit. An autoradiographic study

Blood Coagulation & Fibrinolysis (1994)

Nicanor I. Moldovan Leni Moldovan N Simiónescu

Qualitative ultrastructural autoradiography was used to study the binding of the vascular anticoagulant alpha (annexin V) to normal and atherosclerotic (AS) rabbit aortic intima. Recombinant annexin V was labelled with 125I by the Iodogen method. Rabbits were fed a hypercholesterolemic (HC) diet up to 10 months. After laparotomy and exsanguination, the aortae were perfused with dilutions of 125I-annexin V (I-AV) for 10-15 min, either on ice or at 22 degrees C and then perfusion-fixed with aldehydes. Fragments of the labelled aortae were used for en face contact autoradiography, followed by Sudan Black staining of intimal lipid. Specimens were also included in Epon and sectioned for light- and electron-microscopic autoradiography. The binding of I-AV was increased on the AS aortae as compared with the normal ones, with an apparent preference for the lesioned areas. Microscopically, I-AV was found at the luminal front of aortic intima, on endothelial cells (EC), on macrophage foam cells, and on their disrupted remnants. The presence of the AV binding sites (reportedly known to interact with high affinity with phosphatidylserine) in the rabbit AS aortic intima, together with other known procoagulant conditions, may contribute to the initiation of coagulation events into the lesioned vascular wall, and may offer a rationale for the use of annexin V as an anticoagulant drug.

Lagomorpha

Annexin A5

10.1097/00001721-199412000-00008

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Citations (13)

Differentiated microdomains on the luminal surface of capillary endothelium: distribution of lectin receptors.

The Journal of Cell Biology (1982)

Maya Simionescu N Simiónescu George E. Palade

Lectins conjugated with either peroxidase or ferritin were used to detect specific monosaccharide residues on the luminal front of he fenestrated endothelium in the capillaries of murine pancreas and intestinal mucosa. The lectins tested recognize, if accessible, the following residues: alpha-N-acetylgalactosaminyl (soybean lectin), beta-D-galactosyl (peanut agglutinin [PA] and Ricinus communis agglutinin-120 [RCA]), beta-N-acetylglucosaminyl and sialyl residues (wheat germ agglutinin [WGA]), alpha-L-fucosyl (lotus tetragonolobus lectin), and alpha-D-glucosyl and beta-D-mannosyl (concanavalin A [ConA]). Thi labeled lectins were introduced by perfusion in situ after thoroughly flushing with phosphate-buffered saline the microvascular beds under investigation. Specimens were fixed by perfusion, and subsequently processed for peroxidase detection and electron microscopy. Control experiments included perfusion with: (a) unlabeled lectin before lectin conjugate; (b) labeled lectin together with the cognate hapten sugar, and (c) horseradish peroxidase or ferritin alone. Binding sites were found to be relatively homogeneously distributed on the plasmalemma proper, except for Lotus tetragonolobus lectin and Con A, which frequently bound in patches. Plasmalemmal vesicles, transendothelial channels, and their associated diaphragms were particularly rich in residues recognized by RCA and PA (beta-D-galactosyl residues) and by WGA (beta-N-acetylglucosaminyl residues). Receptors for all lectins tested appeared to be absent or considerably less concentrated on fenestral diaphragms. The results reported here extend and complement previous findings on the existence of microdomains generated by the preferential distribution of chemically different anionic sites (Simionescu et al., 1981, J. Cell Biol., 9:605-613 and 614-621).

Horseradish peroxidase

Soybean agglutinin

10.1083/jcb.94.2.406

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Citations (166)

Radiolabeled multi-layered coated gold nanoparticles as potential biocompatible PET/SPECT tracers

Journal of Materials Chemistry B (2024)

Cristina M. Uritu Cristina M. Al Matarneh Denisse I. Bostiog Adina Coroabă Vlad Ghizdovăţ

The demand for tailored, disease-adapted, and easily accessible radiopharmaceuticals is one of the most persistent challenges in nuclear imaging precision medicine. In this study, two radiotracers were developed to bind SPECT and PET radionuclides.

Biocompatible material

10.1039/d3tb02654j

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Citations (5)

[Effect of the nervous system on compensatory hypertrophy of the adrenal glands].

PubMed (1954)

Milcu Sm N Simiónescu

Compensatory hypertrophy

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