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1.
BMC Med Educ ; 24(1): 1067, 2024 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-39342218

RESUMO

BACKGROUND: The Polish educational system for nurses has undergone a substantial transformation over the past two decades, with the introduction of a mandatory university education that encompasses humanization in medicine. Consequently, nurses who had been licensed to practice before the implementation of the reform returned to universities to pursue master's degrees alongside their younger colleagues who had only recently obtained bachelor's degrees. This distinctive learning environment, in which nurses of varying ages and years of practice study together, offers an opportunity to gain insight into their perspectives on the educational process. Accordingly, the present study aims to examine the opinions of Polish postgraduate nursing students at one university regarding medical humanization courses, focusing on the extent to which these opinions are shaped by age, years of service, and specialty of nursing care. METHODS: From February to June 2023, an anonymous survey was conducted on the university's online platform, involving 89 out of 169 participants in the master's degree nursing program. The newly designed questionnaire comprised 15 primary questions and 11 metric questions. RESULTS: The study population consisted of registered nurses with a mean age of 35 years (ranging from 22 to 54 years). The majority of participants were women (97.8%). The analysis revealed that older students (Spearman's rho 0.480, p < 0.001) and those with more years of professional experience (Spearman's rho 0.377, p < 0.001) perceived humanizing classes as a vital component of nurse training and work. Younger and less experienced students did not share this perspective. Specialization status was also identified as a differentiating factor (Chi² = 10.830, p < 0.05). However, other characteristics, including the number of positions held during the survey, the type of position, the primary employer, and the nature of work (shift or non-shift), did not exhibit statistically significant differentiation among participants. CONCLUSIONS: This study found age- and work-experience-related differences in nursing students' opinions toward courses teaching humanization in health care. The results suggest that changing the teaching format and involving older and more experienced students in sharing experiences with younger and less experienced students could potentially improve the implementation of learned skills in clinical practice.


Assuntos
Educação de Pós-Graduação em Enfermagem , Estudantes de Enfermagem , Humanos , Polônia , Adulto , Feminino , Masculino , Estudantes de Enfermagem/psicologia , Pessoa de Meia-Idade , Fatores Etários , Adulto Jovem , Atitude do Pessoal de Saúde , Humanismo , Inquéritos e Questionários , Especialidades de Enfermagem/educação , Currículo
2.
Neurobiol Dis ; 178: 106006, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36682503

RESUMO

Many fundamental questions on alcohol use disorder (AUD) are frequently difficult to address by examining a single brain structure, but should be viewed from the whole brain perspective. c-Fos is a marker of neuronal activation. Global brain c-Fos profiling in rodents represents a promising platform to study brain functional networks rearrangements in AUD. We used a mouse model of alcohol drinking in IntelliCage. We trained mice to voluntarily drink alcohol, next subjected them to withdrawal and alcohol reexposure. We have developed a dedicated image computational workflow to identify c-Fos-positive cells in three-dimensional images obtained after whole-brain optical clearing and imaging in the light-sheet microscope. We provide a complete list of 169 brain structures with annotated c-Fos expression. We analyzed functional networks, brain modularity and engram index. Brain c-Fos levels in animals reexposed to alcohol were different from both control and binge drinking animals. Structures involved in reward processing, decision making and characteristic for addictive behaviors, such as precommissural nucleus, nucleus Raphe, parts of colliculus and tecta stood out particularly. Alcohol reexposure leads to a massive change of brain modularity including a formation of numerous smaller functional modules grouping structures involved in addiction development. Binge drinking can lead to substantial functional remodeling in the brain. We provide a list of structures that can be used as a target in pharmacotherapy but also point to the networks and modules that can hold therapeutic potential demonstrated by a clinical trial in patients.


Assuntos
Alcoolismo , Consumo Excessivo de Bebidas Alcoólicas , Camundongos , Animais , Consumo Excessivo de Bebidas Alcoólicas/metabolismo , Encéfalo/metabolismo , Etanol , Consumo de Bebidas Alcoólicas/metabolismo , Proteínas Proto-Oncogênicas c-fos/metabolismo
3.
Opt Express ; 30(24): 42810-42828, 2022 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-36522993

RESUMO

Laser-based lensless digital holographic microscopy (LDHM) is often spoiled by considerable coherent noise factor. We propose a novel LDHM method with significantly limited coherent artifacts, e.g., speckle noise and parasitic interference fringes. It is achieved by incorporating a rotating diffuser, which introduces partial spatial coherence and preserves high temporal coherence of laser light, crucial for credible in-line hologram reconstruction. We present the first implementation of the classical rotating diffuser concept in LDHM, significantly increasing the signal-to-noise ratio while preserving the straightforwardness and compactness of the LDHM imaging device. Prior to the introduction of the rotating diffusor, we performed LDHM experimental hardware optimization employing 4 light sources, 4 cameras, and 3 different optical magnifications (camera-sample distances). It was guided by the quantitative assessment of numerical amplitude/phase reconstruction of test targets, conducted upon standard deviation calculation (noise factor quantification), and resolution evaluation (information throughput quantification). Optimized rotating diffuser LDHM (RD-LDHM) method was successfully corroborated in technical test target imaging and examination of challenging biomedical sample (60 µm thick mouse brain tissue slice). Physical minimization of coherent noise (up to 50%) was positively verified, while preserving optimal spatial resolution of phase and amplitude imaging. Coherent noise removal, ensured by proposed RD-LDHM method, is especially important in biomedical inference, as speckles can falsely imitate valid biological features. Combining this favorable outcome with large field-of-view imaging can promote the use of reported RD-LDHM technique in high-throughput stain-free biomedical screening.


Assuntos
Holografia , Microscopia , Camundongos , Animais , Holografia/métodos , Artefatos , Razão Sinal-Ruído , Lasers
4.
Int J Mol Sci ; 23(6)2022 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-35328482

RESUMO

Unsymmetrical bisacridines (UAs) are highly active antitumor compounds. They contain in their structure the drugs previously synthesized in our Department: C-1311 and C-1748. UAs exhibit different properties than their monomer components. They do not intercalate to dsDNA but stabilize the G-quadruplex structures, particularly those of the MYC and KRAS genes. Since MYC and KRAS are often mutated and constitutively expressed in cancer cells, they can be used as therapeutic targets. Herein, we investigate whether UAs can affect the expression and protein level of c-Myc and K-Ras in HCT116 and H460 cancer cells, and if so, what are the consequences for the UAs-induced cellular response. UAs did not affect K-Ras, but they strongly influenced the expression and translation of the c-Myc protein, and in H460 cells, they caused its full inhibition. UAs treatment resulted in apoptosis, as confirmed by the morphological changes, the presence of sub-G1 population and active caspase-3, cleaved PARP, annexin-V/PI staining and a decrease in mitochondrial potential. Importantly, apoptosis was induced earlier and to a greater extent in H460 compared to HCT116 cells. Moreover, accelerated senescence occurred only in H460 cells. In conclusion, the strong inhibition of c-Myc by UAs in H460 cells may participate in the final cellular response (apoptosis, senescence).


Assuntos
Neoplasias Colorretais , Neoplasias Pulmonares , Apoptose , Linhagem Celular Tumoral , Neoplasias Colorretais/patologia , Células HCT116 , Humanos , Pulmão/patologia , Neoplasias Pulmonares/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo
5.
Int J Mol Sci ; 22(13)2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34201632

RESUMO

The rapid development of super-resolution microscopy (SRM) techniques opens new avenues to examine cell and tissue details at a nanometer scale. Due to compatibility with specific labelling approaches, in vivo imaging and the relative ease of sample preparation, SRM appears to be a valuable alternative to laborious electron microscopy techniques. SRM, however, is not free from drawbacks, with the rapid quenching of the fluorescence signal, sensitivity to spherical aberrations and light scattering that typically limits imaging depth up to few micrometers being the most pronounced ones. Recently presented and robustly optimized sets of tissue optical clearing (TOC) techniques turn biological specimens transparent, which greatly increases the tissue thickness that is available for imaging without loss of resolution. Hence, SRM and TOC are naturally synergistic techniques, and a proper combination of these might promptly reveal the three-dimensional structure of entire organs with nanometer resolution. As such, an effort to introduce large-scale volumetric SRM has already started; in this review, we discuss TOC approaches that might be favorable during the preparation of SRM samples. Thus, special emphasis is put on TOC methods that enhance the preservation of fluorescence intensity, offer the homogenous distribution of molecular probes, and vastly decrease spherical aberrations. Finally, we review examples of studies in which both SRM and TOC were successfully applied to study biological systems.


Assuntos
Microscopia/métodos , Imagem Óptica/métodos , Animais , Encéfalo/diagnóstico por imagem , Fluorescência , Corantes Fluorescentes/química , Humanos , Processamento de Imagem Assistida por Computador/métodos , Sondas Moleculares/química , Fixação de Tecidos/métodos
6.
Molecules ; 26(20)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34684841

RESUMO

The culture of 3D spheroids is a promising tool in drug development and testing. Recently, we synthesized a new group of compounds, unsymmetrical bisacridines (UAs), which exhibit high cytotoxicity against various human cell lines and antitumor potency against several xenografts. Here, we describe the ability of four UAs-C-2028, C-2041, C-2045, and C-2053-to influence the growth of HCT116 and H460 spheres and the viability of HCT116 cells in 3D culture compared with that in 2D standard monolayer culture. Spheroids were generated using ultra-low-attachment plates. The morphology and diameters of the obtained spheroids and those treated with UAs were observed and measured under the microscope. The viability of cells exposed to UAs at different concentrations and for different incubation times in 2D and 3D cultures was assessed using 7-AAD staining. All UAs managed to significantly inhibit the growth of HCT116 and H460 spheroids. C-2045 and C-2053 caused the death of the largest population of HCT116 spheroid cells. Although C-2041 seemed to be the most effective in the 2D monolayer experiments, in 3D conditions, it turned out to be the weakest compound. The 3D spheroid culture seems to be a suitable method to examine the efficiency of new antitumor compounds, such as unsymmetrical bisacridines.


Assuntos
Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Esferoides Celulares/efeitos dos fármacos , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Células HCT116 , Humanos
7.
Int J Mol Sci ; 21(11)2020 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-32486425

RESUMO

Activity modulation of drug metabolism enzymes can change the biotransformation of chemotherapeutics and cellular responses induced by them. As a result, drug-drug interactions can be modified. Acridinone derivatives, represented here by C-1305 and C-1311, are potent anticancer drugs. Previous studies in non-cellular systems showed that they are mechanism-based inhibitors of cytochrome P4503A4 and undergo glucuronidation via UDP-glucuronosyltranspherase 1A10 isoenzyme (UGT1A10). Therefore, we investigated the potency of these compounds to modulate P4503A4 and UGT1A10 activity in breast MCF-7 and colon HCT116 cancer cells and their influence on cytotoxicity and cellular response in cells with different expression levels of studied isoenzymes. We show that C-1305 and C-1311 are inducers of not only P4503A4 but also UGT1A10 activity. MCF-7 and HCT116 cells with high P4503A4 activity are more sensitive to acridinone derivatives and undergo apoptosis/necrosis to a greater extent. UGT1A10 was demonstrated to be responsible for C-1305 and C-1311 glucuronidation in cancer cells and glucuronide products were excreted outside the cell very fast. Finally, we show that glucuronidation of C-1305 antitumor agent enhances its pro-apoptotic properties in HCT116 cells, while the cytotoxicity and cellular response induced by C-1311 did not change after drug glucuronidation in both cell lines.


Assuntos
Acridinas/farmacologia , Aminoacridinas/farmacologia , Antineoplásicos/farmacologia , Citocromo P-450 CYP3A/metabolismo , Glucuronosiltransferase/metabolismo , Triazóis/farmacologia , Apoptose , Biotransformação , Linhagem Celular Tumoral , Desenho de Fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Glucuronídeos/metabolismo , Células HCT116 , Humanos , Isoenzimas , Células MCF-7 , Potencial da Membrana Mitocondrial , Necrose , Especificidade por Substrato
8.
J Interprof Care ; 34(1): 50-58, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31037990

RESUMO

The goal of interprofessional education (IPE) is to improve outcomes and experience of healthcare services for patients and families through collaborative practice. While patients and families may participate in IPE experiences as recipients of healthcare services, their perspective on students' emerging collaborative skills is rarely sought. We describe a pediatric IPE activity in which participating families rated students' performance of the targeted interprofessional collaborative competencies. We asked whether family ratings would be consistent with student self-ratings and independent observer ratings. Participants were 40 interprofessional pre-licensure student teams representing physical therapy, occupational therapy, nursing, and speech-language pathology. Each team developed a joint assessment plan, conducted a 1-h play-based observation of a child, 30 months of age or under, and interviewed an accompanying parent/caregiver. Quantitative rating scale data indicated consistency between family, student and independent observer ratings of interprofessional collaborative skills displayed by the students. Qualitative data suggested that students gained a better understanding of ways in which an interprofessional team can provide effective family-centered care. Our results suggest that patient/family feedback can provide a useful measure of the effectiveness of IPE activities and should be included in such activities targeting interprofessional collaborative competences across settings and patient populations.


Assuntos
Comportamento Cooperativo , Família/psicologia , Relações Interprofissionais , Estudantes de Ciências da Saúde/psicologia , Adulto , Competência Cultural , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pais/psicologia , Equipe de Assistência ao Paciente/organização & administração , Autorrelato , Confiança , Adulto Jovem
9.
Postepy Biochem ; 63(1): 8-15, 2017.
Artigo em Polonês | MEDLINE | ID: mdl-28409571

RESUMO

One of the biggest challenges in neuroscience is to understand how brain operates. For this, it would be the best to image the whole brain with at least cellular resolution, preserving the three-dimensional structure in order to capture the connections between different areas. Most currently available high-resolution imaging techniques are based on preparing thin brain sections that are next photographed one by one and subsequently bigger structures are reconstructed. These techniques are laborious and create artifacts. Recent optical clearing methods allow to obtain literally transparent brains that can be imaged using light-sheet microscope. The present review summarizes the most popular optical clearing techniques, describing their different mechanisms and comparing advantages and disadvantages of different approaches, and presents the principle of light-sheet microscopy and its use in imaging. Finally, it gives examples of application of optical tissue clearing and light-sheet imaging in neuroscience and beyond it.


Assuntos
Encéfalo/anatomia & histologia , Neuroimagem/métodos , Humanos , Microscopia
10.
Endocr Pract ; 22(8): 990-8, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27214295

RESUMO

UNLABELLED: Dual-energy X-ray absorptiometry (DXA) is generally a very useful tool for assessing bone mineral density (BMD) and fracture risk. However, observational studies have shown that in certain instances, BMD as measured by DXA systematically over- or underestimates fracture risk. We herein describe the clinical conundrums encountered when assessing fracture risk by DXA in patients with primary hyperparathyroidism or type 2 diabetes and those of Chinese ethnicity. Furthermore, we discuss how advanced imaging technology that examines skeletal microarchitecture is furthering our understanding of fracture risk in these clinical situations. ABBREVIATIONS: BMD = bone mineral density BMI = body mass index BMS = bone material strength BMT = bone microindentation testing 3D = 3-dimensional DM2 = type 2 diabetes mellitus DXA = dual-energy X-ray absorptiometry µFEA = microstructural finite element analysis FRAX = fracture risk assessment tool HRpQCT = high-resolution peripheral quantitative computed tomography ID = indentation distance IDI = indentation distance increase ITS = individual trabecular segmentation PHPT = primary hyperparathyroidism PTH = parathyroid hormone TBS = trabecular bone score.


Assuntos
Absorciometria de Fóton/tendências , Osso e Ossos/diagnóstico por imagem , Diagnóstico por Imagem/tendências , Absorciometria de Fóton/métodos , Densidade Óssea , Diagnóstico por Imagem/métodos , Humanos , Hiperparatireoidismo Primário/diagnóstico por imagem , Vértebras Lombares/diagnóstico por imagem , Fraturas por Osteoporose/diagnóstico por imagem , Tomografia Computadorizada por Raios X
11.
Opt Express ; 22(25): 31496-510, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25607100

RESUMO

We describe a setup consisting of a 4f pulse shaper and a microscope with a high-NA objective lens and discuss the aspects most relevant for an undistorted spatiotemporal profile of the focused beam. We demonstrate shaper-assisted pulse compression in focus to a sub-10-fs duration using phase-resolved interferometric spectral modulation (PRISM). We introduce a nanostructure-based method for sub-diffraction spatiotemporal characterization of strongly focused pulses. The distortions caused by optical aberrations and space-time coupling from the shaper can be reduced by careful setup design and alignment to about 10 nm in space and 1 fs in time.

12.
Acta Pharmacol Sin ; 35(1): 98-112, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24292379

RESUMO

AIM: To examine whether CYP3A4 overexpression influences the metabolism of anticancer agent imidazoacridinone C-1311 in CHO cells and the responses of the cells to C-1311. METHODS: Wild type CHO cells (CHO-WT), CHO cells overexpressing cytochrome P450 reductase (CPR) [CHO-HR] and CHO cells coexpressing CPR and CYP3A4 (CHO-HR-3A4) were used. Metabolic transformation of C-1311 and CYP3A4 activity were measured using RP-HPLC. Flow cytometry analyses were used to examine cell cycle, caspase-3 activity and cell apoptosis. The expression of pH 6.0-dependent ß-galactosidase (SA-ß-gal) was studied to evaluate accelerated senescence. ROS generation was analyzed with CM-H2 DCFDA staining. RESULTS: CYP3A4 overexpression did not change the metabolism of C-1311 in CHO cells: the levels of all metabolites of C-1311 increased with the exposure time to a similar extent, and the differences in the peak level of the main metabolite M3 were statistically insignificant among the three CHO cell lines. In CHO-HR-3A4 cells, C-1311 effectively inhibited CYP3A4 activity without affecting CYP3A4 protein level. In the presence of C-1311, CHO-WT cells underwent rather stable G2/M arrest, while the two types of transfected cells only transiently accumulated at this phase. C-1311-induced apoptosis and necrosis in the two types of transfected cells occurred with a significantly faster speed and to a greater extent than in CHO-WT cells. Additionally, C-1311 induced ROS generation in the two types of transfected cells, but not in CHO-WT cells. Moreover, CHO-HR-3A4 cells that did not die underwent accelerated senescence. CONCLUSION: CYP3A4 overexpression in CHO cells enhances apoptosis induced by C-1311, whereas the metabolism of C-1311 is minimal and does not depend on CYP3A4 expression.


Assuntos
Aminoacridinas/metabolismo , Antineoplásicos/metabolismo , Apoptose/fisiologia , Citocromo P-450 CYP3A/biossíntese , Regulação Enzimológica da Expressão Gênica , Aminoacridinas/farmacologia , Animais , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Células CHO , Cricetinae , Cricetulus , Espécies Reativas de Oxigênio/metabolismo
13.
Biomed Opt Express ; 15(7): 4381-4389, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-39022538

RESUMO

3D super-resolution fluorescence microscopy typically requires sophisticated setups, sample preparation, or long measurements. A notable exception, SOFI, only requires recording a sequence of frames and no hardware modifications whatsoever but being a wide-field method, it faces problems in thick, dense samples. We combine SOFI with temporal focusing two-photon excitation - the wide-field method that is capable of exciting a thin slice in 3D volume. Temporal focusing is simple to implement whenever the excitation path of the microscope can be accessed. The implementation of SOFI is straightforward. By merging these two methods, we obtain super-resolved 3D images of neurons stained with quantum dots. Our approach offers reduced bleaching of out-of-focus fluorescent probes and an improved signal-to-background ratio that can be used when robust resolution improvement is required in thick, dense samples.

14.
Pharmacol Rep ; 2024 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-39361216

RESUMO

BACKGROUND: Pancreatic cancer (PC) is one of the most aggressive cancers and is the seventh leading cause of cancer-related death worldwide. PC is characterized by rapid progression and resistance to conventional treatments. Mutations in KRAS, CDKN2A, TP53, SMAD4/DPC4, and MYC are major genetic alterations associated with poor treatment outcomes in patients with PC. Therefore, optimizing PC therapy is a tremendous challenge. Unsymmetrical bisacridines (UAs), synthesized by our group, are new promising compounds that have exhibited high cytotoxicity and antitumor activity against several solid tumors, including pancreatic cancer. METHODS: The cellular effects induced by UAs in PC cells were evaluated by MTT assay (cell growth inhibition), flow cytometry, and fluorescence and light microscopy (cell cycle distribution, apoptosis, and senescence detection). Analysis of the effects of UAs on the levels of proteins (c-Myc, p53, SMAD4, p21, and p16) was performed by Western blotting. RESULTS: Apoptosis was the main triggered mechanism of death after UAs treatment, and induction of the SMAD4 protein can facilitate this process. c-Myc, which is one of the molecular targets of UAs, can participate in the induction of cell death in a p53-independent manner. Moreover, UAs can also induce accelerated senescence through the upregulation of p21. Notably, senescent cells can die via apoptosis after prolonged exposure to UAs. CONCLUSIONS: UAs have emerged as potent anticancer agents that induce apoptosis by inhibiting c-Myc protein and triggering cellular senescence in a dose-dependent manner by increasing p21 levels. Thus, UAs exhibit desirable features as promising candidates for future pancreatic anticancer therapies.

15.
Carbohydr Polym ; 336: 122120, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38670752

RESUMO

This study introduces a method for producing printable, thermosensitive bioink formulated from agarose (AG) and carbon dioxide-saturated chitosan (CS) hydrogels. The research identified medium molecular weight chitosan as optimal for bioink production, with a preferred chitosan hydrogel content of 40-60 %. Rheological analysis reveals the bioink's pseudoplastic behavior and a sol-gel phase transition between 27.0 and 31.5 °C. The MMW chitosan-based bioink showed also the most stable extrusion characteristic. The choice of chitosan for the production of bioink was also based on the assessment of the antimicrobial activity of the polymer as a function of its molecular weight and the degree of deacetylation, noting significant cell reduction rates for E. coli and S. aureus of 1.72 and 0.54 for optimal bioink composition, respectively. Cytotoxicity assessments via MTT and LDH tests confirm the bioink's safety for L929, HaCaT, and 46BR.1 N cell lines. Additionally, XTT proliferation assay proved the stimulating effect of the bioink on the proliferation of 46BR.1 N fibroblasts, comparable to that observed with Fetal Bovine Serum (FBS). FTIR spectroscopy confirms the bioink as a physical polymer blend. In conclusion, the CS/AG bioink demonstrates the promising potential for advanced spatial cell cultures in tissue engineering applications including skin regeneration.


Assuntos
Dióxido de Carbono , Quitosana , Escherichia coli , Hidrogéis , Tinta , Sefarose , Quitosana/química , Quitosana/farmacologia , Dióxido de Carbono/química , Sefarose/química , Humanos , Hidrogéis/química , Hidrogéis/farmacologia , Animais , Escherichia coli/efeitos dos fármacos , Temperatura , Staphylococcus aureus/efeitos dos fármacos , Camundongos , Reologia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Engenharia Tecidual/métodos , Antibacterianos/farmacologia , Antibacterianos/química , Fibroblastos/efeitos dos fármacos
16.
Drug Metab Dispos ; 41(2): 414-21, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23160818

RESUMO

The acridinone derivates 5-dimethylaminopropylamino-8-hydroxytriazoloacridinone (C-1305) and 5-diethylaminoethylamino-8-hydroxyimidazoacridinone (C-1311) are promising antitumor agents with high activity against several experimental cellular and tumor models and are under evaluation in preclinical and early phase clinical trials. Recent evidence from our laboratories has indicated that both compounds were conjugated by several uridine diphosphate-glucuronyltransferase (UGT) isoforms, the most active being extrahepatic UGT1A10. The present studies were designed to test the ability and selectivity of UGT1A10 in the glucuronidation of acridinone antitumor agents in a cellular context. We show that in KB-3 cells, a HeLa subline lacking expression of any UGT isoforms, both C-1305 and C-1311 undergo metabolic transformation to the glucuronidated forms on overexpression of UGT1A10. Furthermore, UGT1A10 overexpression significantly increased the cytotoxicity of C-1305, but not C-1311, suggesting that the glucuronide was more potent than the C-1305 parent compound. These responses were selective for UGT1A10 because documented overexpression of UGT2B4 failed to produce glucuronide products and failed to alter the cytotoxicity for both compounds. These findings contribute to our understanding of the mechanisms of action of these agents and are of particular significance because data for C-1305 contradict the dogma that glucuronidation typically plays a role in detoxification or deactivation. In summary, these studies suggest that extrahepatic UGT1A10 plays an important role in the metabolism and the bioactivation of C-1305 and constitutes the basis for further mechanistic studies on the mode of action of this drug, as well as translational studies on the role of this enzyme in regulation of C-1305 toxicity in cancer.


Assuntos
Acridinas/metabolismo , Acridinas/farmacologia , Aminoacridinas/metabolismo , Aminoacridinas/farmacologia , Antineoplásicos/metabolismo , Antineoplásicos/farmacologia , Glucuronosiltransferase/metabolismo , Triazóis/metabolismo , Triazóis/farmacologia , Neoplasias do Colo do Útero/enzimologia , Biotransformação , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Feminino , Glucuronídeos/metabolismo , Glucuronídeos/farmacologia , Glucuronosiltransferase/genética , Células HeLa , Humanos , Concentração Inibidora 50 , Transfecção , Neoplasias do Colo do Útero/genética , Neoplasias do Colo do Útero/patologia
17.
Cell Biol Int ; 37(2): 109-20, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23319370

RESUMO

There is increasing evidence that the expression level of drug metabolic enzymes affects the final cellular response following drug treatment. Moreover, anti-tumour agents may modulate enzymatic activity and/or cellular expression of metabolic enzymes in tumour cells. We have investigated the influence of CYP3A4 overexpression on the cellular response induced by the anti-tumour agent C-1311 in hepatoma cells. C-1311-mediated CYP3A4 activity modulation and the effect of CYP3A4 overexpression on C-1311 metabolism have also been examined. With the HepG2 cell line and its CYP3A4-overexpressing variant, Hep3A4, experiments involving DAPI staining, cell cycle analysis, phosphatidylserine externalisation and senescence-associated (SA)-ß-galactosidase expression, were used to monitor the effects of C-1311 exposure. C-1311 cellular metabolism and CYP3A4 activity were investigated by high-performance liquid chromatography. C-1311 metabolism was very low in both hepatoma cell lines and slightly influenced by CYP3A4 expression. Interestingly, in HepG2 cells, C-1311 was an effective modulator of CYP3A4 enzymatic activity, being the inhibitor of this isoenzyme in Hep3A4 cells. Cell cycle analysis showed that HepG2 cells underwent a rather stable G(2) /M arrest following C-1311 exposure, whereas CYP3A4-overexpressing cells accumulated only slightly in this compartment. C-1311-treated cells died by apoptosis and necrosis, whereas surviving cells underwent senescence; however, these effects occurred faster and more intensely in Hep3A4 cells. Although CYP3A4 did not influence C-1311 metabolism, changes in CYP3A4 levels affected the C-1311-induced response in hepatoma cells. Therefore, inter-patient differences in CYP3A4 levels should be considered when assessing the potential therapeutic effects of C-1311.


Assuntos
Aminoacridinas/farmacologia , Antineoplásicos/farmacologia , Apoptose , Carcinoma Hepatocelular/tratamento farmacológico , Senescência Celular , Citocromo P-450 CYP3A/genética , Neoplasias Hepáticas/tratamento farmacológico , Necrose/metabolismo , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Citocromo P-450 CYP3A/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Necrose/tratamento farmacológico
18.
Acta Pharmacol Sin ; 34(1): 146-56, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23160340

RESUMO

AIM: To examine how the higher expression level of CYP3A4 isoenzyme influenced the cytotoxicity of the antitumor triazoloacridinone derivative C-1305 in Chinese hamster ovary (CHO) cells. METHODS: Three CHO cell lines were examined: wild-type CHO cells; CHO-HR cells with overexpression of human cytochrome P450 reductase (CPR); and CHO-HR-3A4 cells with coexpression of human CYP3A4 and CPR. Cellular responses caused by C-1305 were monitored using DAPI staining, cell cycle analysis, phosphatydilserine externalization analysis and SA-ß-galactosidase expression analysis. Cell viability was assessed with simultaneous FDA and PI staining. RESULTS: Treatment with C-1305 for 72 h exhibited different levels of cytotoxicity in the 3 cell lines, and the values of IC80 in CHO, CHO-HR and CHO-HR-3A4 cells were 0.087±0.005, 0.032±0.0001, and 0.064±0.0095 µmol/L, respectively. The cell cycle analysis revealed that both CHO and CHO-HR cells underwent transient G(2)/M arrest, whereas CHO-HR-3A4 cells did not accumulate in this phase. Prolonged exposure up to 120 h caused time-dependent increase in the sub-G(1) fraction in all the 3 cell lines. Treatment with C-1305 caused cell death through apoptosis and necrosis. However, these processes were more pronounced in the transfected CHO cells than in the wild-type cells. The cells surviving after C-1305 exposure underwent senescence. CONCLUSION: CYP3A4 overexpression potently enhances the cellular responses (apoptosis, necrosis and senescence) caused by C-1305 in CHO cells.


Assuntos
Acridinas/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Citocromo P-450 CYP3A/genética , Citotoxinas/farmacologia , Triazóis/farmacologia , Regulação para Cima , Animais , Células CHO , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cricetinae , Cricetulus , Humanos
19.
RSC Adv ; 13(13): 8830-8843, 2023 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-36936819

RESUMO

Several molecular cobalt(ii) complexes, one Co(ii) coordination polymer and one ionic cobalt(iii) complex with imine hemisalen ligands were synthesized. The hemisalen ligands were synthesized from o-vanillin (oVP) and diverse aminopyridines (compounds HL1-HL4) or aminophenol (compound HL5). It was observed that cobalt(ii) chloride in dry acetonitrile catalyzes a transformation of HL1 and HL3 instead of complex formation. The conversion of these imines proceeded via self-cyclization to N-2''-pyridyl-2,6-dioxo-9-aza-[c,g]di-2'-methoxybenzo nonan or its methyl derivative as the major product. The remaining reactions were performed using imines HL1-HL5 and cobalt(ii) acetate Co(Ac)2 in methanol or DMSO/acetonitrile resulting in forming a series of cobalt complexes. The following series of compounds was obtained: two similar tetrahedral molecular Co(ii) complexes [Co(L1)2] and [Co(L3)2], one trinuclear, mixed-ligand Co3(Ac)2(L4)2(oVP)2, one coordination polymer {Co(L2)2}∞ and finally one octahedral anionic Co(iii) complex [HNEt3][Co(L5)3]. The latter complex formed in a cobalt(ii) acetate reaction with a hemisalen HL5 derived from oVP and 2-aminophenol. The molecular structures of all compounds were confirmed by X-ray diffraction, and the cytotoxicity of Co(ii) and Co(iii) complexes towards cancer cell lines HCT116, HL-60 and normal cell line MRC-5 was studied.

20.
Transl Psychiatry ; 13(1): 20, 2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36683039

RESUMO

Natural rewards, such as food, and sex are appetitive stimuli available for animals in their natural environment. Similarly, addictive rewards such as drugs of abuse possess strong, positive valence, but their action relies on their pharmacological properties. Nevertheless, it is believed that both of these kinds of rewards activate similar brain circuitry. The present study aimed to discover which parts of the brain process the experience of natural and addictive rewards. To holistically address this question, we used a single-cell whole-brain imaging approach to find patterns of activation for acute and prolonged sucrose and cocaine exposure. We analyzed almost 400 brain structures and created a brain-wide map of specific, c-Fos-positive neurons engaged by these rewards. Acute but not prolonged sucrose exposure triggered a massive c-Fos expression throughout the brain. Cocaine exposure on the other hand potentiated c-Fos expression with prolonged use, engaging more structures than sucrose treatment. The functional connectivity analysis unraveled an increase in brain modularity after the initial exposure to both types of rewards. This modularity was increased after repeated cocaine, but not sucrose, intake. To check whether discrepancies between the processing of both types of rewards can be found on a cellular level, we further studied the nucleus accumbens, one of the most strongly activated brain structures by both sucrose and cocaine experience. We found a high overlap between natural and addictive rewards on the level of c-Fos expression. Electrophysiological measurements of cellular correlates of synaptic plasticity revealed that natural and addictive rewards alike induce the accumulation of silent synapses. These results strengthen the hypothesis that in the nucleus accumbens drugs of abuse cause maladaptive neuronal plasticity in the circuitry that typically processes natural rewards.


Assuntos
Cocaína , Animais , Cocaína/farmacologia , Açúcares/metabolismo , Núcleo Accumbens/metabolismo , Recompensa , Neurônios/metabolismo , Sacarose/metabolismo , Sacarose/farmacologia
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