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18 results on '"Rudys, Romualdas"'

10. Microlesion healing dynamics in in vivo porcine skin after treatment with 1064 nm picosecond‐domain Nd:YAG laser.

Author

Baleisis, Justinas and Rudys, Romualdas

Abstract

The fractionated picosecond laser produces microscopic lesions in the epidermis and dermis due to laser‐induced optical breakdown (LIOB). There have been multiple histological reports, but the present literature lacks detailed in vivo studies after treatment with high‐power laser systems. Our study aimed to characterize the healing patterns of microlesions induced with 150 ps duration 1064 nm MLA‐type picosecond laser. The induced picosecond laser‐tissue reactions with pulse energy of 50–250 mJ and different treatment modes were observed in in vivo porcine skin model over 10 days after the laser procedure. A macroscopic evaluation was combined with microscopic histological analysis to observe the healing dynamics of laser‐induced microlesions. Superficial, intraepidermal cavitation bubbles were induced using microbeam fluence of 4–20 J/cm2. Skin irritation scores positively correlated with pulse energy and dose. Our findings demonstrate that dose and pulse energy had a direct impact on epidermal thickness and lesions healing dynamics. [ABSTRACT FROM AUTHOR]

Published
2023
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12. Detection of endogenous porphyrins by means of spectroscopy and microscopy in the case of rheumatoid arthritis

Author

Rudys, Romualdas, GADONAS, ROALDAS, ALABURDA, AIDAS, DADONIENĖ, JOLANTA, MATULIS, DAUMANTAS, JUZĖNAS, PETRAS, BAGDONAS, SAULIUS, and Vilnius University

Subjects
musculoskeletal diseases, Microscopy, Spektroskopija, Mikroskopija, Spectroscopy, microscopy, endogenous porphyrins, rheumatoid arthritis, aminolevulinic acid, Biophysics, Endogenous porphyrins, Rheumatoid arthritis, Aminolevulinic acid, Endogeniniai porfirinai, Reumatoidinis artritas, Aminolevulininė rūgštis
Abstract

Rheumatoid arthritis (RA) is an autoimmune disease, which affects 0.5–1.0 % of adults. The aim of this thesis is to study accumulation and localization of endogenous porphyrins by means of spectroscopy and microscopy in experimental rheumatoid arthritis model and postoperative samples of patients after application of 5-aminolevulinic acid or its methyl ester. The spectroscopic measurements of endogenous porphyrins were performed in synoviocytes, chondrons and cartilage explants of patients with RA or osteoarthritis (OA) and in rabbit antigen induced arthritis model. The localization of endogenous porphyrins in synovium and cartilage tissues of rabbit knee joints was determined based on fluorescence spectroscopy, fluorescence intensity and lifetime microscopy, and histology imaging results. Studies showed that selective sensitization of inflamed synovium in the in vitro model may be achieved using ALA and ALA-Me, while in the in vivo model only using ALA-Me. The photosensitizer protoporphyrin IX induced by these precursors is accumulated in the cells of synovium and cartilage tissues. The results presented in this dissertation can be used anticipating to apply the sensitization with endogenous porphyrins for diagnostic and therapeutic purposes in the case of rheumatoid arthritis. Reumatoidinis artritas (RA) yra autoimuninė liga, kuria pasaulyje serga 0,5-1 % suaugusių žmonių. Disertacijos tikslas – spektroskopiniais ir mikroskopiniais metodais ištirti endogeninių porfirinų susikaupimą ir pasiskirstymą eksperimentinio reumatoidinio artrito modelyje ir pacientų pooperacinėje medžiagoje po 5-aminolevulininės rūgšties (ALA) ar jos metilo esterio (ALA-Me) panaudojimo. Atlikti endogeninių porfirinų fluorescencinės spektroskopijos tyrimai RA ir osteoartritu sergančių (OA) pacientų sinoviocituose, chondronuose ir kremzlės bandiniuose bei triušių antigenu indukuotame artrito modelyje. Endogeninių porfirinų lokalizacija triušių kelio sąnario kremzlės ir sinovijos audiniuose nustatyta remiantis fluorescencinės spektroskopijos, fluorescencijos intensyvumo ir gyvavimo trukmių mikroskopijos bei histologinių vaizdų analizės rezultatais. Tyrimais nustatyta, kad selektyviai sensibilizuoti uždegiminę sinoviją modelyje in vitro galima naudojant ALA bei ALA-Me, o modelyje in vivo tik ALA-Me. Šių pirmtakų indukuotas fotosensibilizatorius protoporfirinas IX yra susikaupęs sinovijos ir kremzlės audinių ląstelėse. Disertaciniame darbe pristatomų tyrimų rezultatai gali būti panaudoti norint ateityje endogeniniais porfirinais pagrįstą sensibilizaciją pritaikyti diagnostikos ir terapijos tikslais reumatoidinio artrito atveju.

Published
2014

16. Cell surface markers and exogenously induced Pp IX in synovial mesenchymal stem cells.

Author

Denkovskij, Jaroslav, Rudys, Romualdas, Bernotiene, Eiva, Minderis, Mindaugas, Bagdonas, Saulius, and Kirdaite, Gailute

Abstract

The aim of present study was to assess the expression of surface markers and the accumulation of protoporphyrin IX in synovial mesenchymal stem cells (SMSCs). SMSC from patients with rheumatoid arthritis (RA, n = 5) and osteoarthritis (OA, n = 5-6) were characterized and their PpIX accumulation rates were evaluated by flow cytometry. The expression of the 21 out of 24 tested surface markers, related to stem-like features and aggressiveness of cells showed no statistically significant differences between RA and OA groups. However, the cells from RA group had the significantly lower levels of expression for the integrin-associated protein CD47 and the grow factor receptor CD271 ( P = 0.018), while the higher levels of cell membrane zinc-dependent metalloproteinase CD10 ( P = 0.006), as compared to the cells from OA group. Comparison of the mean intensities of PpIX fluorescence revealed no statistically significant differences between the RA and OA groups, as well as no relation to proliferation rates or cell size, although some conspicuous distinction in PpIX accumulation was observed in certain specimens within these groups, suggesting possibilities of this method application for characterization of individual SMSC populations. CD10, CD47, and CD271 were differently expressed in RA and OA SMSC, while had no direct association with the PpIX fluorescence intensity. © 2015 International Society for Advancement of Cytometry [ABSTRACT FROM AUTHOR]

Published
2015
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17. Fluorescence morphology and fluorescence lifetime imaging microscopy (FLIM) of rabbit knee tissues in the experimental arthritis model.

Author

RUDYS, Romualdas, BAGDONAS, Saulius, KIRDAITĖ, Gailutė, PAPEČKIENĖ, Jurga, and ROTOMSKIS, Ričardas

Subjects
*ARTHRITIS prevention, *LUMINESCENCE spectroscopy, *TISSUES, *RADIOACTIVITY, *CELLS
Abstract

The article explores the potential of using fluorescence morphology and fluorescence lifetime imaging micro spy (FILM) in assessing tissues in an experimental arthritis model. Topics discussed include the prevalence of chronic inflammatory diseases of the joints around the world, the equipment and materials used for the fluorescence measurements and the effectiveness FILM in predicting arthritis.

Published
2012

18. Skin autofluorescence photo-bleaching and photo-memory

Author

Lesins, Janis, Lihachev, Alexey, Rudys, Romualdas, Bagdonas, Saulius, and Spigulis, Janis

Abstract

Photo-bleaching of in-vivo skin autofluorescence intensity under continuous low power laser irradiation has been studied. Temporal behavior of single-spot fluorescence and spectral fluorescent images have been studied at continuous 405 nm, 473 nm and 532 nm laser excitation and/or pre-irradiation, with power densities well below the laser-skin safety limits. Skin autofluorescence photo-memory effects (laser signatures) have been observed and analyzed, as well.

Published
2011
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