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1.
Biomedicines ; 12(3)2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38540272

RESUMO

The human knee is a complex joint that comprises several ligaments, including the medial collateral ligament (MCL). The MCL provides stability to the knee and helps prevent its excessive inward movement. The MCL also has a thin layer of connective tissue known as the epiligament (EL), which adheres to the ligament. This unique feature has drawn attention in the field of ligament healing research, as it may have implications for the recovery process of MCL injuries. According to the EL theory, ligament regeneration relies heavily on the provision of cells, blood vessels, and molecules. The present study sought to compare the expression of vascular endothelial growth factor (VEGF), CD34, and α-smooth muscle actin (α-SMA) in healthy knees' proximal and distal MCL segments to better understand how these proteins affect ligament healing. By improving the EL theory, the current results could lead to more effective treatments for ligament injury. To conduct the present analysis, monoclonal antibodies were used against CD34, α-SMA, and VEGF to examine samples from 12 fresh knee joints' midsubstance MCLs. We identified a higher cell density in the EL than in the ligament connective tissue, with higher cell counts in the distal than in the proximal EL part. CD34 immunostaining was weak or absent in blood vessels and the EL, while α-SMA immunostaining was strongest in smooth muscle cells and the EL superficial layer. VEGF expression was mainly in the blood vessels' tunica media. The distal part showed more SMA-positive microscopy fields and higher cell density than the proximal part (4735 vs. 2680 cells/mm2). Our study identified CD34, α-SMA, and VEGF expression in the MCL EL, highlighting their critical role in ligament healing. Differences in α-SMA expression and cell numbers between the ligament's proximal and distal parts may explain different healing capacities, supporting the validity of the EL theory in ligament recovery.

2.
Biomedicines ; 12(1)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38255261

RESUMO

The aim of this study was to assess the epiligament theory by determining the normal epiligament morphology of the proximal and distal parts of the anterior cruciate ligament in humans and analyzing the differences between them and the midportion of the ligament in terms of cell numbers and expression of CD34 and α-SMA. Samples were obtained from the anterior cruciate ligaments of 12 fresh knee joints. Monoclonal antibodies against CD34 and α-SMA were used for immunohistochemistry. Photomicrographs were analyzed using ImageJ software, version 1.53f. The cell density was higher in the epiligament than in the ligament connective tissue. Cell counts were higher in the proximal and distal thirds than in the midsubstance of the epiligament. CD34 was expressed similarly in the proximal and distal thirds, although it seemed slightly more pronounced in the distal third. α-SMA expression was more robust in the proximal than the distal part. The results revealed that CD34 and α-SMA are expressed in the human epiligament. The differences between the numbers of cells in the proximal and distal parts of the epiligament and the expression of CD34 and α-SMA enhance epiligament theory. Future investigations into improving the quality of ligament healing should not overlook the epiligament theory.

4.
Pharmaceuticals (Basel) ; 16(9)2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37765006

RESUMO

A series of ten new hydrazide-hydrazone derivatives bearing a pyrrole ring were synthesized and structurally elucidated through appropriate spectral characteristics. The target hydrazones were assessed for radical scavenging activity through 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) tests, with ethyl 5-(4-bromophenyl)-1-(2-(2-(4-hydroxy-3,5-dimethoxybenzylidene)hydrazine-yl)-2-oxoethyl)-2-methyl-1H-pyrrole-3-carboxylate (7d) and ethyl 5-(4-bromophenyl)-1-(3-(2-(4-hydroxy-3,5-dimethoxybenzylidene) hydra zine-yl)-3-oxopropyl)-2-methyl-1H-pyrrole-3-carboxylate (8d) highlighted as the best radical scavengers from the series. Additional density functional theory (DFT) studies have indicated that the best radical scavenging ligands in the newly synthesized molecules are stable, do not decompose into elements, are less polarizable, and with a hard nature. The energy of the highest occupied molecular orbital (HOMO) revealed that both compounds possess good electron donation capacities. Overall, 7d and 8d can readily scavenge free radicals in biological systems via the donation of hydrogen atoms and single electron transfer. The performed in vitro assessment of the compound's protective activity on the H2O2-induced oxidative stress model on human neuroblastoma cell line SH-SY5Y determined 7d as the most perspective representative with the lowest cellular toxicity and the highest protection.

5.
Gels ; 9(6)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37367121

RESUMO

Nanogels are attractive drug delivery systems that provide high loading capacity for drug molecules, improve their stability, and increase cellular uptake. Natural antioxidants, especially polyphenols such as resveratrol, are distinguished by low aqueous solubility, which hinders therapeutic activity. Thus, in the present study, resveratrol was incorporated into nanogel particles, aiming to improve its protective effects in vitro. The nanogel was prepared from natural substances via esterification of citric acid and pentane-1,2,5-triol. High encapsulation efficiency (94.5%) was achieved by applying the solvent evaporation method. Dynamic light scattering, atomic force microscopy, and transmission electron microscopy revealed that the resveratrol-loaded nanogel particles were spherical in shape with nanoscopic dimensions (220 nm). In vitro release tests showed that a complete release of resveratrol was achieved for 24 h, whereas at the same time the non-encapsulated drug was poorly dissolved. The protective effect of the encapsulated resveratrol against oxidative stress in fibroblast and neuroblastoma cells was significantly stronger compared to the non-encapsulated drug. Similarly, the protection in a model of iron/ascorbic acid-induced lipid peroxidation on rat liver and brain microsomes was higher with the encapsulated resveratrol. In conclusion, embedding resveratrol in this newly developed nanogel improved its biopharmaceutical properties and protective effects in oxidative stress models.

6.
Pharmaceutics ; 15(4)2023 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-37111772

RESUMO

The anthracycline antibiotic doxorubicin is a well-known antitumour agent, however its cardiotoxicity is a significant obstacle to therapy. The aim of the present study was to improve the safety of doxorubicin through its simultaneous encapsulation with a cardioprotective agent (resveratrol) in Pluronic micelles. The formation and double-loading of the micelles was performed via the film hydration method. Infrared spectroscopy proved the successful incorporation of both drugs. X-ray diffraction analyses revealed that resveratrol was loaded in the core, whereas doxorubicin was included in the shell. The double-loaded micelles were characterised by a small diameter (26 nm) and narrow size distribution, which is beneficial for enhanced permeability and retention effects. The in vitro dissolution tests showed that the release of doxorubicin depended on the pH of the medium and was faster than that of resveratrol. In vitro studies on cardioblasts showed the opportunity to reduce the cytotoxicity of doxorubicin through the presence of resveratrol in double-loaded micelles. Higher cardioprotection was observed when the cells were treated with the double-loaded micelles compared with referent solutions with equal concentrations of both drugs. In parallel, treatments of L5178 lymphoma cells with the double-loaded micelles revealed that the cytotoxic effect of doxorubicin was enhanced. Thus, the study demonstrated that the simultaneous delivery of doxorubicin and resveratrol via the micellar system enabled the cytotoxicity of doxorubicin in lymphoma cells and lowered its cardiotoxicity in cardiac cells.

7.
Pharmaceutics ; 14(12)2022 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-36559117

RESUMO

The present study is focused on the development of cannabidiol-loaded polymeric nanomicelles as a drug delivery system with neuroprotective effects. Cannabidiol was loaded in Pluronic micelles (Pluronic P123 or its combination with Pluronic F127) possessing an average diameter smaller than 50 nm and high encapsulation efficiency for the hydrophobic drug (80% and 84%, respectively). The successful encapsulation and transformation of cannabidiol in amorphous phase were observed by IR spectroscopy and X-ray diffraction, respectively. Studies with neuroblastoma cells (SH-SY5Y and Neuro-2a) showed that the pure cannabidiol caused a dose-dependent reduction of cell viability, whereas its loading into the micelles decreased cytotoxicity. Further, neuroprotective effects of pure and micellar cannabidiol were examined in a model of H2O2-induced oxidative stress in both neuroblastoma cells. The pre-treatment of cell lines with cannabidiol loaded into the mixed Pluronic P123/F127 micelles exerted significantly stronger protection against the oxidative stress compared to pure cannabidiol and cannabidiol in single Pluronic P123 micelles. Interestingly, the empty mixed P123/F127 micelles demonstrated protective activity against the oxidative stress. In conclusion, the study revealed the opportunity to formulate a new drug delivery system of cannabidiol, in particular nanosized micellar aqueous dispersion, that could be considered as a perspective platform for cannabidiol application in neurodegenerative diseases.

8.
Knee ; 39: 78-90, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36179587

RESUMO

BACKGROUND: This study evaluated and compared the expression of VEGF, CD34, and α-SMA in the anterior cruciate ligaments and medial collateral ligaments in healthy human knees in order to enrich the epiligament theory regarding ligament healing after injury. METHODS: Samples from the mid-substance of the anterior cruciate ligament and the medial collateral ligament of 12 fresh knee joints were used. Monoclonal antibodies against CD34, α-SMA, and VEGF were used for immunohistochemical analysis. Photomicrographs were analyzed using the ImageJ software. RESULTS: The epiligament of the anterior cruciate ligament showed slightly higher expression of CD34, α-SMA, and VEGF than the epiligament of the medial collateral ligament. Overall, among the tested markers, α-SMA expression was most pronounced in anterior cruciate ligament epiligament images and CD34 dominated in medial collateral ligament epiligament images. The intensity of DAB staining for CD34, α-SMA, and VEGF was higher in vascular areas of the epiligament than in epiligament connective tissue. CONCLUSIONS: The results illustrate that CD34, α-SMA, and VEGF are expressed in the human epiligament. The differences between the epiligament of the investigated ligaments and the fact that CD34, α-SMA, and VEGF, which are known to have a definite role in ligament healing, are predominantly expressed in the main vascular part of the ligament-epiligament complex enlarge the existing epiligament theory. Future investigations regarding better ligament healing should not overlook the epiligament tissue.


Assuntos
Ligamento Cruzado Anterior , Ligamentos Colaterais , Ligamento Colateral Médio do Joelho , Cicatrização , Humanos , Actinas/metabolismo , Ligamento Cruzado Anterior/anatomia & histologia , Ligamento Cruzado Anterior/metabolismo , Lesões do Ligamento Cruzado Anterior/metabolismo , Lesões do Ligamento Cruzado Anterior/patologia , Articulação do Joelho/anatomia & histologia , Articulação do Joelho/metabolismo , Ligamento Colateral Médio do Joelho/anatomia & histologia , Ligamento Colateral Médio do Joelho/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Cicatrização/fisiologia , Antígenos CD34/metabolismo
9.
Front Pharmacol ; 13: 831791, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35321325

RESUMO

Sdox is a hydrogen sulfide (H2S)-releasing doxorubicin effective in P-glycoprotein-overexpressing/doxorubicin-resistant tumor models and not cytotoxic, as the parental drug, in H9c2 cardiomyocytes. The aim of this study was the assessment of Sdox drug-like features and its absorption, distribution, metabolism, and excretion (ADME)/toxicity properties, by a multi- and transdisciplinary in silico, in vitro, and in vivo approach. Doxorubicin was used as the reference compound. The in silico profiling suggested that Sdox possesses higher lipophilicity and lower solubility compared to doxorubicin, and the off-targets prediction revealed relevant differences between Dox and Sdox towards several cancer targets, suggesting different toxicological profiles. In vitro data showed that Sdox is a substrate with lower affinity for P-glycoprotein, less hepatotoxic, and causes less oxidative damage than doxorubicin. Both anthracyclines inhibited CYP3A4, but not hERG currents. Unlike doxorubicin, the percentage of zebrafish live embryos at 72 hpf was not affected by Sdox treatment. In conclusion, these findings demonstrate that Sdox displays a more favorable drug-like ADME/toxicity profile than doxorubicin, different selectivity towards cancer targets, along with a greater preclinical efficacy in resistant tumors. Therefore, Sdox represents a prototype of innovative anthracyclines, worthy of further investigations in clinical settings.

10.
Dermatol Ther ; 35(4): e15357, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35119712

RESUMO

Congenital melanocytic nevi (CMN) are quite common benign proliferations of cutaneous melanocytes. They are present at birth or arise during the first few weeks of life being upper and lower extremities one of the most common locations. To date, consistent guidelines for clinical management of CMN do not yet exist and the main reasons for removing them are medical and cosmetic. Regardless of the cause of having a CMN removed, when it comes to surgical excision of the lesion in daily practice, the single most important decision to make is how to properly close the post-excisional defect. The local Dufourmentel skin flap seems to be a reliable solution for surgical treatment of medium-sized CMN on the limbs. It takes advantage of skin laxity adjаcent to thе defect to allоw the transpositiоn of tissuе with similаr charactеristics tо the tissuе еxcisеd, which is the key for achieving good aesthetic and functional outcomes. In this brief clinical study, the author identified a group of adult patients, who had medium-sized CMN located on their extremities. The surgical technique is explained and useful tips are given. No complications and high patient satisfaction rate were registered in the series. Dufourmentel flap is a useful tool in the armamentarium of dermatologic surgery when dealing with medium-sized CMN on the extremities. Furthermore, due to its versatility this flap could also be applied for other clinical indications both benign and malignant.


Assuntos
Nevo Pigmentado , Neoplasias Cutâneas , Adulto , Extremidades/patologia , Extremidades/cirurgia , Humanos , Recém-Nascido , Melanócitos , Nevo Pigmentado/patologia , Neoplasias Cutâneas/patologia , Retalhos Cirúrgicos/patologia
12.
Nat Commun ; 12(1): 1123, 2021 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-33602938

RESUMO

Bud-break is an economically and environmentally important process in trees and shrubs from boreal and temperate latitudes, but its molecular mechanisms are poorly understood. Here, we show that two previously reported transcription factors, EARLY BUD BREAK 1 (EBB1) and SHORT VEGETATIVE PHASE-Like (SVL) directly interact to control bud-break. EBB1 is a positive regulator of bud-break, whereas SVL is a negative regulator of bud-break. EBB1 directly and negatively regulates SVL expression. We further report the identification and characterization of the EBB3 gene. EBB3 is a temperature-responsive, epigenetically-regulated, positive regulator of bud-break that provides a direct link to activation of the cell cycle during bud-break. EBB3 is an AP2/ERF transcription factor that positively and directly regulates CYCLIND3.1 gene. Our results reveal the architecture of a putative regulatory module that links temperature-mediated control of bud-break with activation of cell cycle.


Assuntos
Dormência de Plantas/fisiologia , Proteínas de Plantas/metabolismo , Populus/crescimento & desenvolvimento , Populus/metabolismo , Estações do Ano , Ácido Abscísico/metabolismo , Epigênese Genética , Flores/fisiologia , Regulação da Expressão Gênica de Plantas , Modelos Biológicos , Mutação/genética , Fenótipo , Proteínas de Plantas/genética , Populus/genética , Regiões Promotoras Genéticas/genética , Transcriptoma/genética
13.
Hortic Res ; 8(1): 37, 2021 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-33574224

RESUMO

Betula L. (birch) is a pioneer hardwood tree species with ecological, economic, and evolutionary importance in the Northern Hemisphere. We sequenced the Betula platyphylla genome and assembled the sequences into 14 chromosomes. The Betula genome lacks evidence of recent whole-genome duplication and has the same paleoploidy level as Vitis vinifera and Prunus mume. Phylogenetic analysis of lignin pathway genes coupled with tissue-specific expression patterns provided clues for understanding the formation of higher ratios of syringyl to guaiacyl lignin observed in Betula species. Our transcriptome analysis of leaf tissues under a time-series cold stress experiment revealed the presence of the MEKK1-MKK2-MPK4 cascade and six additional mitogen-activated protein kinases that can be linked to a gene regulatory network involving many transcription factors and cold tolerance genes. Our genomic and transcriptome analyses provide insight into the structures, features, and evolution of the B. platyphylla genome. The chromosome-level genome and gene resources of B. platyphylla obtained in this study will facilitate the identification of important and essential genes governing important traits of trees and genetic improvement of B. platyphylla.

14.
Aesthet Surg J ; 41(8): 944-949, 2021 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-33592089

RESUMO

BACKGROUND: Dealing with remaining penilе deformities following surgery to correct complications after injection of nonabsorbable substаnces tends to be troublesome. There is a lack of adequate information regarding the options for the management of such residual irregularities. In morе than 2 decades of clinical application, hyaluronic acid (HA) fillers have proved to be a safе and reliable solution fоr a great variety of age-related changes, tissue atrophy, and contour deformities. OBJECTIVES: This brief clinical study aimed to demоnstrate the author's initial еxperience with the novel use of an HA-based filler for the correction of secondary deformities of penile girth. METHODS: Rеtrospective analysis was conducted, encompassing patients who underwent correction of secondary penile deformities with HA between August 2018 and February 2020. Тhe procedures were carried оut in an ambulatory setting and a blunt cannula was used for filler infiltration. A 9-month follow-up was established. RESULTS: Five patients aged between 29 and 44 years (average, 35.8 years) were found and included in the study. The mean volumе of HA product used for the correction was 3.32 mL. An analysis of the outcomes demonstrated a high satisfaction ratе among pаtients with no complications in thе series. CONCLUSIONS: The procedure is safe, effective, and relatively simple with reproducible and reliable outcomes. Due to its excellent spreading and good tissue integration, the selected HA filler was very useful in cases where fibrosis was present because of previous surgeries.


Assuntos
Ácido Hialurônico , Pênis , Adulto , Humanos , Injeções , Masculino , Pênis/cirurgia , Estudos Retrospectivos
15.
Drug Chem Toxicol ; 44(3): 238-249, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-30822164

RESUMO

Lomefloxacin (LF) is interesting as a model molecule from a safety point of view because of its high potential for serious adverse drug effects (i.e. phototoxic reactions). In this study, MCM-41 mesoporous silica nanoparticles (MCM-41) were loaded with lomefloxacin, aiming to overcome the drug's intrinsic cytotoxicity. The good biocompatibility of the empty drug carrier (0.1-1.0 mg/ml) was established by the absence of red blood cell lysis (hemolysis assay). The cytotoxicity of empty MCM-41 and lomefloxacin-loaded MCM-41 (LF-MCM-41) was evaluated by using a battery of in vitro cytotoxicity assays: Alamar blue, lactate dehydrogenase release and reactive oxygen species formation by dichlorofluorescein assay. Three cell cultures models: hepatoma HepG2, fibroblasts L929 and endothelial EA.hy926 cells were used to compare the cytotoxicity and reactive oxygen species formation by free drug, empty MCM-41, and LF-MCM-41. The findings from the study indicated that empty MCM-41 (0.1-1.0 mg/ml) showed a low cytotoxic potential in HepG2, followed by L929 and EA.hy926 cells. Lomefloxacin loading in MCM-41 mesoporous silica nanocarrier reduced the cytotoxicity of the free lomefloxacin, especially in the high concentration (1.0 mg/ml MCM-41, containing 120 µg/ml LF). L929 and EA.hy926 cells were more sensitive to the protective effects of LF-MCM-41, compared to HepG2 cells. The results indicate that an improvement in lomefloxacin safety might be expected after incorporation in an appropriate drug delivery system.


Assuntos
Sistemas de Liberação de Medicamentos , Fluoroquinolonas/administração & dosagem , Nanopartículas , Dióxido de Silício/química , Animais , Antibacterianos/administração & dosagem , Antibacterianos/toxicidade , Linhagem Celular , Portadores de Fármacos/química , Células Endoteliais/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fluoroquinolonas/toxicidade , Células Hep G2 , Humanos , Camundongos , Espécies Reativas de Oxigênio/metabolismo
16.
Pharm Dev Technol ; 25(10): 1271-1280, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32892659

RESUMO

Caffeic acid phenethyl ester (CAPE), a major pharmacologically active component of poplar type propolis, is known for its proapoptotic, anti-inflammatory, antioxidant, antiviral, and enzyme inhibiting activities. The aim of this study was to perform an in vitro and in vivo safety assessment of a micellar system based on a newly synthesized copolymer, consisting of polyglycidol and poly(allyl glycidyl ether) (C12-PAGE-PG) as a drug delivery platform for CAPE. The in vitro studies on HepG2 and L929 cells by MTT and LDH assays after treatment with the empty and CAPE-loaded micelles showed no cytotoxic effects of the empty micelles and retained cytotoxic activity of CAPE loaded in the micelles. No hemolysis or stimulation of mouse lymphocytes or macrophages was observed in vitro. In vivo hematological, biochemical, and histological assays on rats, treated with the empty (2580 and 5160 µg/kg) or CAPE-loaded (375 and 750 µg CAPE/kg) micelles did not reveal pathological changes of any of the parameters assayed after 14-days' treatment. In conclusion, initial toxicological data characterize C12-PAGE-PG as a non-toxic and promising copolymer for development of micellar drug delivery systems, particularly for a hydrophobic active substance as CAPE.


Assuntos
Ácidos Cafeicos/administração & dosagem , Sistemas de Liberação de Medicamentos , Álcool Feniletílico/análogos & derivados , Polímeros/química , Animais , Ácidos Cafeicos/toxicidade , Linhagem Celular , Compostos de Epóxi/química , Células Hep G2 , Humanos , Interações Hidrofóbicas e Hidrofílicas , Masculino , Camundongos , Micelas , Álcool Feniletílico/administração & dosagem , Álcool Feniletílico/toxicidade , Propilenoglicóis/química , Ratos , Ratos Wistar
18.
Acta Pharm ; 70(3): 303-324, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32074071

RESUMO

Six new N-pyrrolylhydrazide hydrazones were synthesized under micro synthesis conditions, assuring about 59-93 % yield, low harmful emissions and reagent economy. The structures of the new compounds were elucidated by melting points, TLC characteristics, IR, 1H and 13C NMR spectral data followed by MS data. The purity of the obtained compounds was proven by the corresponding elemental analyses. "Lipinski's rule of five" parameters were applied for preliminary evaluation of the pharmacokinetic properties of the target molecules. The initial in vitro safety screening for cytotoxicity (on HepG2 cells) and hemocompatibility (hemolysis assay) showed good safety of the new compounds, where ethyl 5-(4-bromophenyl)-1-(1-(2-(4-hydroxy-3-methoxybenzylidene)-hydrazineyl)-1-oxo-3-phenylpropan-2-yl)-2-methyl-1H-pyr-role-3-carboxylate (4d) and ethyl 5-(4-bromophenyl)-1-(1-(2-(2-hydroxybenzylidene)hydrazineyl)-1-oxo-3-phenylpropan--2-yl)-2-methyl-1H-pyrrole-3-carboxylate (4a) were the least toxic. The antioxidant activity in terms of radical scavenging activity (DPPH test) and reducing ability (ABTS) was also evaluated. The antioxidant protective potential of the compounds was next determined in different in vitro cellular-based models, revealing compounds 4d and 3 [ethyl 5-(4-bromophenyl)-1-(1-hydrazineyl-1-oxo-3-phenylpropan-2-yl)-2-methyl-1H-pyrrole-3-carboxylate] as the most promising compounds, with 4d having better safety profile.


Assuntos
Antioxidantes/farmacologia , Hidrazonas/farmacologia , Pirróis/farmacologia , Animais , Antioxidantes/química , Antioxidantes/toxicidade , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/farmacologia , Sequestradores de Radicais Livres/toxicidade , Hemólise/efeitos dos fármacos , Células Hep G2 , Humanos , Hidrazonas/química , Hidrazonas/toxicidade , Masculino , Pirróis/química , Pirróis/toxicidade , Ratos , Ratos Wistar , Relação Estrutura-Atividade
19.
Toxicol Mech Methods ; 30(2): 146-152, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31736404

RESUMO

Phase-contrast micrographs are often used for confirmation of proliferation and viability assays. However, they are usually only a qualitative tool and fail to exclude with certainty the presence of assay interference by test substances. The complexity of image analysis workflows hinders life scientists from routinely utilizing micrograph data. Here, we present an open-source software-based, combined ilastik segmentation/ImageJ measurement of area (ISIMA) approach for cell monolayer segmentation and confluence percentage measurement of phase-contrast micrographs of Hep G2 cells. The aim of this study is to test whether the proposed approach is suitable for quantitative confirmation of proliferation data, acquired by the 3-(4,5-Dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay. Our results show that ISIMA is user-friendly and provides reproducible data, which strongly correlates to the results of the MTT assay. In conclusion, ISIMA is an affordable, simple, and fast approach for confluence quantification by researchers without image analysis background.


Assuntos
Técnicas de Cultura de Células/instrumentação , Processamento de Imagem Assistida por Computador , Microscopia de Contraste de Fase/métodos , Algoritmos , Proliferação de Células , Sobrevivência Celular , Células Hep G2 , Humanos
20.
Plant Biotechnol J ; 18(6): 1434-1443, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31799778

RESUMO

We investigated feasibility of the Full-length complementary DNA OvereXpression (FOX) system as a mutagenesis approach in poplar, using developing xylem tissue. The main goal was to assess the overall mutation rate and if the system will increase instances of mutants affected in traits linked to the xylem tissue. Indeed, we found a high mutation rate of 17.7%, whereas 80% of all mutants were significantly affected in cellulose, lignin and/or hemicellulose. Cell wall biosynthesis is a major process occurring during xylem development. Enrichment of mutants affected in cell wall composition suggests that the tissue source for the FOX library influenced the occurrence of mutants affected in a trait linked to this tissue. Additionally, we found that FLcDNAs from mutants affected in cell wall composition were homologous to genes known to be involved in cell wall biosynthesis and most recovered FLcDNAs corresponded to genes whose native expression was highest in xylem. We characterized in detail a mutant line with increased diameter. The phenotype was caused by a poplar homolog of LONELY GUY 1 (LOG1), which encodes an enzyme in cytokinin biosynthesis and significantly increased xylem proliferation. The causative role of LOG1 in the observed phenotype was further reaffirmed by elevated cytokinin concentration in the mutant and recapitulation overexpression experiment wherein multiple independent lines phenocopied the original FOX mutant. Our experiments show that the FOX approach can be efficiently used for gene discovery and molecular interrogation of traits specific to woody perennial growth and development.


Assuntos
Populus , Madeira , Parede Celular/genética , Parede Celular/metabolismo , Regulação da Expressão Gênica de Plantas/genética , Biblioteca Gênica , Lignina/metabolismo , Taxa de Mutação , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Populus/genética , Populus/metabolismo , Madeira/genética , Madeira/metabolismo , Xilema/genética , Xilema/metabolismo
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