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300 results on '"Dumitrescu, Luminita"'

7. Macrophage Immunomodulation and Suppression of Bacterial Growth by Polydimethylsiloxane Surface-Interrupted Microlines' Topography Targeting Breast Implant Applications.

Author

Negrescu, Andreea Mariana, Nistorescu, Simona, Bonciu, Anca Florina, Rusen, Laurentiu, Dumitrescu, Luminita Nicoleta, Urzica, Iuliana, Cimpean, Anisoara, and Dinca, Valentina

Subjects
BREAST implants, BACTERIAL colonies, BACTERIAL contamination, MAMMAPLASTY, SURFACE energy, BREAST
Abstract

Since breast cancer is one of the most common forms of cancer in women, silicone mammary implants have been extensively employed in numerous breast reconstruction procedures. However, despite the crucial role they play, their interaction with the host's immune system and microbiome is poorly understood. Considering this, the present work investigates the immunomodulatory and bacterial mitigation potential of six textured surfaces, based on linear step-like features with various regular and irregular multiscaled arrangements, in comparison to a flat PDMS surface. We hypothesise that the chosen surface geometries are capable of modulating the cellular response through mechanical interdigitation within the multiscaled surface morphology, independent of the surface chemical properties. Each type of sample was characterised from a physico-chemical and biological points of view and by comparison to the flat PDMS surface. The overall results proved that the presence of linear multiscaled step-like features on the PDMS surface influenced both the surface's characteristics (e.g., surface energy, wettability, and roughness parameters), as well as the cellular response. Thus, the biological evaluation revealed that, to different degrees, biomaterial-induced macrophage activation can be mitigated by the newly designed microtextured surfaces. Moreover, the reduction in bacteria adherence up to 90%, suggested that the topographical altered surfaces are capable of suppressing bacterial colonisation, therefore demonstrating that in a surgical environment at risk of bacterial contamination, they can be better tolerated. [ABSTRACT FROM AUTHOR]

Published
2024
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16. SYNTHESIS AND OPTICAL PROPERTIES OF NOVEL STRONTIUM TETRANITROPHTHALOCYANINE.

Author

GROZA, Silviu, STOEAN, Bianca, GROZAV, Adriana, CRACIUN, Ana-Maria, CRISTEA, Castelia, SILAGHI-DUMITRESCU, Luminita, and PORUMB, Dan

Subjects
OPTICAL properties, PHTHALIC acid, ACID derivatives, ULTRAVIOLET-visible spectroscopy, STRONTIUM, FLUORESCENCE, COPPER
Abstract

Two convenient alternatives for the synthesis of metal(II) 2,9,16,23-tetranitrophthalocyanines (TNPc) were applied in the synthesis of the novel Strontium(II)TNPc and its Zinc(II)TNPc, Copper(II)TNPc and Cobalt(II)TNPc analogues. The thermal activation required for the tetramerization of the phthalic acid derivatives used as substrates (4-nitrophthalimide or 4-nitrophthalodinitrile) was provided by convective heating in solution or solvent free conditions. The optical properties of the synthesized metal(II)TNPc were compared by means of UV-vis spectroscopy. In solution, the novel Sr(II)TNPc was characterized by absorption bands with maxima situated around 690 nm (similar to Cu(II)TNPc), while its fluorescence emission maxima lays close to Zn(II)TNPc (710 nm), with a three times longer fluorescence emission life time in solid state (3.04 ns). [ABSTRACT FROM AUTHOR]

Published
2023
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17. STRUCTURAL AND OPTICAL INSIGHTS INTO A PHENOTHIAZINE-DERIVED CHALCONE SYNTHESIZED VIA ECO-FRIENDLY METHODS.

Author

GRAMA, Stefana, STOEAN, Bianca, TURZA, Alexandru, PORUMB, Dan, CRISTEA, Castelia, and SILAGHI-DUMITRESCU, Luminita

Subjects
CHALCONE, STOKES shift, ENERGY consumption, ULTRAVIOLET-visible spectroscopy, OPTICAL properties, HYDROGEN bonding
Abstract

A novel chalcone containing (hetero)aromatic units was obtained by the Claisen-Schmidt condensation of phenothiazinyl-3-carbaldehyde with 4-hydroxy-acetophenone under three experimental approaches based on classical, mechanochemical and ultrasound-assisted procedures. A comparison between the experimental outcomes emphasizes shorter reaction time and lower energy usage in the case of mechanochemical and ultrasound-assisted procedures, recommending these methods as more environmentally friendly synthetic options. Moreover, the use of the sonochemical method resulted in the formation of the reaction product in crystalline state thus simplifying the purification process. The optical properties of the new chalcone were assessed by UV-vis spectroscopy. (E)-1-(4-hydroxyphenyl)-3-(10-methyl-10H-phenothiazin-3-yl)prop-2-en-1-one exhibited an intense absorption in the UV region (γmax=408 nm) and low intensity fluorescence emission in DMSO solution (γem=560 nm, Stokes shift 7558 cm-1). The X-ray diffraction on monocrystal technique which was employed to ascertain the solid-state structure of the new chalcone revealed strong O-H···O hydrogen bonds and weak dispersive van der Waals interactions such as π···π and C-H···π contacts ensuring its supramolecular architecture, crystal cohesion and stability. [ABSTRACT FROM AUTHOR]

Published
2023
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37. Structural and metabolic profiling of Lycopersicon esculentum rhizosphere microbiota artificially exposed at commonly used Non-Steroidal Anti-Inflammatory Drugs

Author

Szilaghi-Dumitrescu Luminita, Emoke Dalma Kovacs, and Tian Di

Subjects
stomatognathic diseases, Rhizosphere, Non steroidal anti inflammatory, Biology, biology.organism_classification, Lycopersicon, Microbiology
Abstract

In this study the effect of common non-steroidal anti-inflammatory drugs on Lycopersicon esculentum rhizosphere microbiota was monitored. Results evidenced that rhizosphere microbiota abundance decreased especially under exposure to diclofenac and ibuprofen while fungal/bacteria ratio changed significantly with exposure to diclofenac and ketoprofen. Compared with control samples the average amount of ratio of gram negative/gram positive bacteria was higher in rhizosphere soil contaminated with ibuprofen and lower in case of diclofenac contamination. Carbon source consumption increased with time of assay in case of control samples and those contaminated with diclofenac. This suggests that rhizosphere microbiota under contamination with diclofenac consume higher amount of carbon although do not consume a larger variety of its sources. In case of contamination with ibuprofen and ketoprofen the consumption of carbon source presents a decreasing tendency after day 30 of the assay. Rhizosphere microbiota emitted volatile organic compounds were also monitored. Volatile compounds belonging to alcohol, aromatic compounds, ketone, terpene, organic acids, aldehyde, sulphur compounds, esters, alkane, nitrogen compounds, alkene and furans were detected in rhizosphere soil samples. Among these, terpene, ketone, alcohol, aromatic compounds, organic acids, and alkane were the most abundant compound classes, but their percentage changed with exposure at diclofenac, ketoprofen and ibuprofen. Such changes in abundance, structure, and metabolic activity of Lycopersicon esculentum rhizosphere microbiota under exposure to common non-steroidal anti-inflammatory drugs make as to suppose that there is a probability to also change ecosystem services provided by rhizosphere microbiota.

Published
2021
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40. ALTERNATIVE PROCEDURES FOR THE GREEN SYNTHESIS OF 3,7-BIS(N,N-(2- HYDROXYETHYL)AMINO)PHENOTHIAZINIUM DYE.

Author

GAL, Melinda, TURZA, Alexandru, STOEAN, Bianca, GAINA, Luiza, CRISTEA, Castelia, GAL, Emese, LOVASZ, Tamas, PORUMB, Dan, and SILAGHI-DUMITRESCU, Luminita

Subjects
STOKES shift, OPTICAL properties, ENERGY consumption, AQUEOUS solutions, X-ray diffraction
Abstract

Two experimental procedures implying mechanochemical and ultrasounds assisted protocols were assessed as alternatives to the classical synthesis of the title MB analogue, based on the substitution of the phenothiazinium tetraiodide with diethanolamine nucleophile. These greener alternatives required a much shorter reaction time and consequently less energy consumption. The sonochemical procedure gave a crystalline reaction product demanding a facile purification. UV-vis spectroscopic analysis emphasized the optical properties of the 3,7- bis(N,N-(2-hydroxyethyl)amino)phenothiazinium dye characterized by an intense absorption maxima situated at 663 nm and weak fluorescence emission in aqueous solution (quatum yield 0.7% relative to methylene blue standard) with the emission maxima situated at 685 nm (Stokes shift 484 cm-1). The solid state structure of the dye was determined by X-ray diffraction. [ABSTRACT FROM AUTHOR]

Published
2022
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47. Evaluation of palliative care at home: the families' perspective

Author

Dumitrescu, Luminita

Subjects
Palliative treatment -- Research, Palliative treatment -- Demographic aspects, Home care -- Research, Family -- Research, Conflict (Psychology) -- Prevention, Health, Health care industry, Social sciences
Published
2007

49. Novel (Phenothiazinyl)Vinyl-Pyridinium Dyes and Their Potential Applications as Cellular Staining Agents

Author

Stoean, Bianca, primary, Rugina, Dumitrita, additional, Focsan, Monica, additional, Craciun, Ana-Maria, additional, Nistor, Mǎdǎlina, additional, Lovasz, Tamas, additional, Turza, Alexandru, additional, Porumb, Ioan-Dan, additional, Gál, Emese, additional, Cristea, Castelia, additional, Silaghi-Dumitrescu, Luminita, additional, Astilean, Simion, additional, and Gaina, Luiza Ioana, additional

Published
2021
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