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1.
Biosensors (Basel) ; 14(1)2024 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-38248418

RESUMO

This study delves into the intricate interaction between DNA and nanosystems, exploring its potential implications for biomedical applications. The focus lies in understanding the adsorption geometry of DNA when in proximity to plasmonic nanoparticles, utilizing ultrasensitive vibrational spectroscopy techniques. Employing a combined Raman-SERS analysis, we conducted an in-depth examination to clarify the molecular geometry of interactions between DNA and silver nanoparticles. Our findings also reveal distinctive spectral features regarding DNA samples due to their distinctive genome stability. To understand the subtle differences occurring between normal and cancerous DNA, their thermal stability was investigated by means of SERS measurement performed before and after a thermal treatment at 94 °C. It was proved that thermal treatment did not affect DNA integrity in the case of normal cells. On the other hand, due to epimutation pattern that characterizes cancerous DNA, variations between spectra recorded before and after heat treatment were observed, suggesting genome instability. These findings highlight the potential of DNA analysis using SERS for cancer detection. They demonstrate the applicability of this approach to overcoming challenges associated with low DNA concentrations (e.g., circulating tumor DNA) that occur in biofluids. In conclusion, this research contributes significant insights into the nanoscale behavior of DNA in the presence of nanosystems.


Assuntos
Nanopartículas Metálicas , Neoplasias , Prata , DNA , Adsorção , Epigênese Genética , Neoplasias/diagnóstico
2.
Pharmaceutics ; 14(2)2022 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-35214041

RESUMO

Glioblastoma (GBM) is a lethal brain cancer with a very difficult therapeutic approach and ultimately frustrating results. Currently, therapeutic success is mainly limited by the high degree of genetic and phenotypic heterogeneity, the blood brain barrier (BBB), as well as increased drug resistance. Temozolomide (TMZ), a monofunctional alkylating agent, is the first line chemotherapeutic drug for GBM treatment. Yet, the therapeutic efficacy of TMZ suffers from its inability to cross the BBB and very short half-life (~2 h), which requires high doses of this drug for a proper therapeutic effect. Encapsulation in a (nano)carrier is a promising strategy to effectively improve the therapeutic effect of TMZ against GBM. Although research on liposomes as carriers for therapeutic agents is still at an early stage, their integration in GBM treatment has a great potential to advance understanding and treating this disease. In this review, we provide a critical discussion on the preparation methods and physico-chemical properties of liposomes, with a particular emphasis on TMZ-liposomal formulations targeting GBM developed within the last decade. Furthermore, an overview on liposome-based formulations applied to translational oncology and clinical trials formulations in GBM treatment is provided. We emphasize that despite many years of intense research, more careful investigations are still needed to solve the main issues related to the manufacture of reproducible liposomal TMZ formulations for guaranteed translation to the market.

3.
Pharmaceutics ; 11(7)2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31266139

RESUMO

In the present study, the antitumoral potential of three gel formulations loaded with carbon dots prepared from N-hydroxyphthalimide (CD-NHF) was examined and the influence of the gels on two types of skin melanoma cell lines and two types of breast cancer cell lines in 2D (cultured cells in normal plastic plates) and 3D (Matrigel) models was investigated. Antitumoral gels based on sodium alginate (AS), carboxymethyl cellulose (CMC), and the carbomer Ultrez 10 (CARB) loaded with CD-NHF were developed according to an adapted method reported by Hellerbach. Viscoelastic properties of CD-NHF-loaded gels were analyzed by rheological analysis. Also, for both CD-NHF and CD-NHF-loaded gels, the fluorescence properties were analyzed. Cell proliferation, apoptosis, and mitochondrial activity were analyzed according to basic methods used to evaluate modulatory activities of putative anticancer agents, which include reference cancer cell line culture assays in both classic 2D and 3D cultures. Using the rheological measurements, the mechanical properties of gel formulations were analyzed; all samples presented gel-like rheological characteristics. The presence of CD-NHF within the gels induces a slight decrease of the dynamic moduli, indicating a flexible gel structure. The fluorescence investigations showed that for the gel-loaded CD-NHF, the most intense emission peak was located at 370 nm (upon excitation at 330 nm). 3D cell cultures displayed visibly larger structure of tumor cells with less active phenotype appearance. The in vitro results for tested CD-NHF-loaded gel formulations revealed that the new composites are able to affect the number, size, and cellular organization of spheroids and impact individual tumor cell ability to proliferate and aggregate in spheroids.

4.
J Burn Care Res ; 38(1): 1-10, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27893580

RESUMO

Both adipose-derived stem cells (ADSCs) and fat grafting promote burn wound healing, but whether adipogen-derived cells using various inducers such as 3-isobutyl-1-methylxanthine (IBMX) and insulin affect wound healing is unknown. Herein, ADSC-differentiated adipogenic lineages were used in rat burn wounds to evaluate wound healing potential. ADSCs were cultivated using six different adipogenic differentiation conditions (IBMX ± insulin, IBMX for 5 days, high and low Dulbecco's modified Eagle's medium) and in vitro morphological changes and cell proliferations during adipogenic differentiation were recorded. Intermediate burn wounds were inflicted in 15 Wistar male rats. Afterwards, the rats were divided into five groups for subcutaneous injections under the wounds: control; ADSCs; differentiated adipocytes (-IBMX+INSULIN and +IBMX[D1-5]+INSULIN) and fat prepared by Coleman technique. Macroscopic changes and histology were documented for 3 weeks. Repeated measures analysis of variance was performed to analyze cell growth and wound healing with a statistical level set of P < .05. Induction cocktails significantly reduced proliferation and induced lipid droplet accumulation. Conditioning without insulin induced the least lipid accumulation, while discontinuing IBMX generated larger adipocytes (P < .001). Adipogenic differentiated ADSCs had similar wound healing abilities with ADSC and fat injections, but differentiated adipocytes (+IBMX[D1-5]+INSULIN) and fat grafting accelerated the early healing process relative to ADSC (P < .001). Reduced fibrosis and mild inflammatory infiltration limited to superficial dermis were observed in +IBMX(D1-5)+INSULIN and fat injection groups, while those reactions were mild to moderate in ADSC group. Differentiated adipocytes achieve similar wound healing results compared with ADSC and fat injections, but differentiated adipocytes (+IBMX[D1-5]+INSULIN) and fat grafting accelerate early healing relative to ADSC.


Assuntos
Adipócitos/transplante , Queimaduras/patologia , Queimaduras/terapia , Cicatrização , 1-Metil-3-Isobutilxantina , Adipogenia , Animais , Técnicas de Cultura de Células , Proliferação de Células , Insulina , Masculino , Ratos , Ratos Wistar , Células-Tronco
5.
Rev Med Chir Soc Med Nat Iasi ; 120(1): 77-82, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27125076

RESUMO

UNLABELLED: Angiotensin II has articularly shown to play a key role in the regulation of inflammatory processes in hypertension. AIM: The present study aims to correlate the angiotensin II-induced hypertension 4th systemic inflammation. MATERIAL AND METHODS: We conducted an experimental study on Wistar male rats who received Ang II via subcutaneous miniosmotic pumps for 2 weeks. Rats were exposed to a 12h light /12h dark cycle. Sham rats were used as control. Systolic load pressure measurements and a flow cytometric analysis of lymphocyte surface markers were performed. After 14 days, the animals were euthanized under anesthesia with ylazine/ketaniine. RESULTS: Systolic BP progressively and significantly increased in rats 4th Ang II chronic infusion. We observed a statistical significant difference (p = 0.00001), in terms of T lymphocytes percentage between control rats plasma and Ang H treated rats lasma, in 14 days. CONCLUSIONS: Angiotensin II is an important mediator of hypertension and directly promotes inflammation by noticeably increasing the quantity of T cells in kidney tissue.


Assuntos
Angiotensina II , Hipertensão/metabolismo , Sistema Renina-Angiotensina , Vasoconstritores , Animais , Modelos Animais de Doenças , Hipertensão/etiologia , Hipertensão/fisiopatologia , Inflamação/metabolismo , Masculino , Ratos , Ratos Wistar , Sistema Renina-Angiotensina/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos
6.
Rom J Morphol Embryol ; 55(1): 97-102, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24715172

RESUMO

The current literature related to colorectal cancer shows there is a great inhomogeneity in patient outcome, even between patients in the same stage, which means that the TNM staging does not seem enough anymore to make a therapeutic decision. This is why many of the recent studies focus on the study of prognostic and predictive factors that would make the therapeutic decision-making process more accurate. In the current study, we focused on the study of two lymph node based scores - the lymph node ratio and the log odds ratio and the morphological characteristics of the tumor to try to see if any of them can predict a more aggressive tumor behavior in order to approach the patient in an appropriate way. The study included 25 patients presenting over a period of two years (2009-2011) for a local relapse or a metastasis after curative surgery for colorectal cancer. From the morphological characteristics of the tumor, only the protruding character of the tumor positively correlated at a statistically significant level with the recurrence-free time. We also proved that between the two lymph node scores and the pN stage, the log odds ratio was the one that best correlated with both the number of invaded lymph nodes and the number of resected nodes. The log odds ratio also proved to correlate well with the risk of developing a distant metastasis. Our study also shows for the first time that the log odds ratio is able to stratify patients according to their risk of a fast relapse.


Assuntos
Neoplasias Colorretais/patologia , Linfonodos/patologia , Recidiva Local de Neoplasia/diagnóstico , Adulto , Idoso , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , Razão de Chances , Prognóstico , Estatísticas não Paramétricas
7.
Biomed Res Int ; 2013: 286902, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24073397

RESUMO

BACKGROUND/AIM: Tumour angiogenesis defined by microvessel density (MVD) is generally accepted as a prognostic factor in breast cancer. However, due to variability of measurement systems and cutoffs, it is questionable to date whether it contributes to predictive outline. Our study aims to grade vascular heterogeneity by comparing clear-cut compartments: tumour associated stroma (TAS), tumour parenchyma, and tumour invasive front. MATERIAL AND METHODS: Computerized vessel area measurement was performed using a tissue cytometry system (TissueFAXS) on slides originated from 50 patients with breast cancer. Vessels were marked using immunohistochemistry with CD34. Regions of interest were manually defined for each tumour compartment. RESULTS: Tumour invasive front vascular endothelia area was 2.15 times higher than that in tumour parenchyma and 4.61 times higher than that in TAS (P < 0.002). Worth to mention that the lymph node negative subgroup of patients show a slight but constant increase of vessel index in all examined compartments of breast tumour. CONCLUSION: Whole slide digital examination and region of interest (ROI) analysis are a valuable tool in scoring angiogenesis markers and disclosing their prognostic capacity. Our study reveals compartments' variability of vessel density inside the tumour and highlights the propensity of invasive front to associate an active process of angiogenesis with potential implications in adjuvant therapy.


Assuntos
Neoplasias da Mama/irrigação sanguínea , Neoplasias da Mama/patologia , Microscopia/métodos , Neovascularização Patológica/patologia , Adulto , Idoso , Antígenos CD34/metabolismo , Endotélio/patologia , Feminino , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica , Estatística como Assunto , Células Estromais/patologia
8.
Stem Cells Dev ; 21(10): 1604-15, 2012 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-21933023

RESUMO

Myelodysplastic syndromes (MDSs) are clonal disorders of hematopoietic stem cells (HSCs) characterized by ineffective hematopoiesis. MDSs are responsible for 1 or several peripheral cytopenias. The evidence accumulated in recent years demonstrates that in addition to HSC defects, a particular role is also played by stromal microenvironment dysfunctions, which mediate the direct contact with hematopoietic precursor cells (HPCs). These interactions help regulate different adhesion-related processes, such as progenitor cell proliferation, apoptosis, clonogenic growth, and maintenance in in vitro cultures. As previously reported, these interactions are responsible for altering the microenvironment in MDS. Herein, we present a novel selection protocol for obtaining a standards-compliant mesenchymal stromal cell (MSC) preparation. This method allowed us to comparatively analyze 2 subpopulations of bone marrow MSCs (BM-MSCs) in terms of their adhesion profiles and growth abilities: BM-MSCs selected from MDS settings and their normal counterparts. Functional assays revealed that the MSCs from MDS are intrinsically pathological, thus showing a continuous decline of proliferation and a reduced clonogenic capacity during 14 days of culture and in the absence of signals from hematopoietic cells. The MSC growth defects were significantly correlated with decreases in CD44 adhesion molecules and CD49e (α5-integrin).


Assuntos
Proliferação de Células , Receptores de Hialuronatos/metabolismo , Integrina alfa5/metabolismo , Células-Tronco Mesenquimais/fisiologia , Síndromes Mielodisplásicas/patologia , 5'-Nucleotidase/metabolismo , Idoso , Antígenos de Superfície/metabolismo , Células da Medula Óssea/metabolismo , Células da Medula Óssea/fisiologia , Estudos de Casos e Controles , Adesão Celular , Moléculas de Adesão Celular/metabolismo , Separação Celular , Forma Celular , Tamanho Celular , Células Cultivadas , Ensaio de Unidades Formadoras de Colônias , Citometria de Fluxo , Proteínas Ligadas por GPI/metabolismo , Humanos , Imunofenotipagem , Células-Tronco Mesenquimais/metabolismo , Pessoa de Meia-Idade
9.
Biomark Med ; 5(5): 655-60, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22003916

RESUMO

The Romanian Association of Medical Laboratories (RAML) conferences have acquired a reputation for standing out as the most prominent and efficient meetings in the national community of laboratory medicine, being a landmark of the development in this field in Romania and an active affiliation to international forums. This year, the conference setting was Piatra Neamt, in the northeast part of Romania, which produced a friendly and stimulating professional environment. As in previous years, leading experts in the fields of laboratory medicine attended the event. This year, we enjoyed the opportunity to have such distinguished guests as the members of the executive board of International Federation of Clinical Chemistry and Laboratory Medicine (IFCC); Graham Beastall, IFCC President; Päivi Hannele Laitinen, IFCC secretary; and Grazyna Sypniewska, IFCC Communication and Publication Division, and editor of the electronic journal of the IFCC. As usual, the conference program included all aspects of clinical laboratory activity, with a special focus on technology development, instrumentation and laboratory management. Fully aware of the fact that the complexity and depth of laboratory practice have undergone an impressive and rapid evolution, the specific goals of the event were to increase knowledge in the fundamentals of new molecular investigation, areas which show the tendency to become routine in our daily activity. In addition, laboratory management and the place of medical laboratories in the process of translational medicine were subjects of focus. The 6th Conference of the Romanian Association of Medical Laboratories was held from Wednesday 1st to Saturday 4th of June 2011. A total of 273 participants from all local branches of the Association attended. The scientific program included seven plenary sessions where 22 lectures and 18 short communications were delivered, and three poster sessions with 44 poster presentations. Session topics covered issues of laboratory diagnostics in hematology, biochemistry, immunology, oncology, microbiology and metabolic diseases. A prominent consideration was given to value added to laboratory medicine in the frame of managed care and quality management. The Conference was accompanied by a laboratory equipment and reagents exhibition with the participation of nine companies, also sponsors of the conference. Three workshops pointed out the presence of the most well known of them: Abbott, Roche and Nobis.


Assuntos
Laboratórios/organização & administração , Técnicas de Laboratório Clínico , Romênia , Pesquisa Translacional Biomédica
10.
Exp Cell Res ; 317(18): 2616-29, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21871449

RESUMO

Direct cell-cell contact between haematopoietic progenitor cells (HPCs) and their cellular microenvironment is essential to maintain 'stemness'. In cancer biology, focal adhesion (FA) proteins are involved in survival signal transduction in a wide variety of human tumours. To define the role of FA proteins in the haematopoietic microenvironment of myelodysplastic syndromes (MDS), CD73-positive mesenchymal stromal cells (MSCs) were immunostained for paxillin, pFAK [Y(397)], and HSP90α/ß and p130CAS, and analysed for reactivity, intensity and cellular localisation. Immunofluorescence microscopy allowed us to identify qualitative and quantitative differences, and subcellular localisation analysis revealed that in pathological MSCs, paxillin, pFAK [Y(397)], and HSP90α/ß formed nuclear molecular complexes. Increased expression of paxillin, pFAK [Y(397)], and HSP90α/ß and enhanced nuclear co-localisation of these proteins correlated with a consistent proliferative advantage in MSCs from patients with refractory anaemia with excess blasts (RAEB) and negatively impacted clonogenicity of HPCs. These results suggest that signalling via FA proteins could be implicated in HPC-MSC interactions. Further, because FAK is an HSP90α/ß client protein, these results suggest the utility of HSP90α/ß inhibition as a target for adjuvant therapy for myelodysplasia.


Assuntos
Adesões Focais/metabolismo , Mesoderma/patologia , Síndromes Mielodisplásicas/metabolismo , Paxilina/metabolismo , Células Estromais/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína Substrato Associada a Crk/metabolismo , Proteína-Tirosina Quinases de Adesão Focal/metabolismo , Adesões Focais/patologia , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Mesoderma/metabolismo , Pessoa de Meia-Idade , Síndromes Mielodisplásicas/patologia , Células Estromais/metabolismo
11.
Fam Cancer ; 9(4): 519-23, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20567915

RESUMO

Breast cancer is the most common cancer in women worldwide, including Romania, where its incidence has increased significantly during the last decade. Ovarian cancer is the fourth leading cause of mortality by cancer in women. BRCA1 and BRCA2 are major cancer predisposition genes, responsible for a large percentage of hereditary breast and ovarian cancer (HBOC) families. We investigated 17 patients from unrelated HBOC families in north-eastern Romania, screening for mutations in BRCA1 and BRCA2 by mutation-specific PCR and by dideoxy sequencing. We identified four BRCA1 and two BRCA2 mutations in the 17 families. The overall mutation frequency was 41% (7/17; 5 BRCA1 and 2 BRCA2). Two mutations (BRCA1 c.2241dupC and BRCA2 c.8680C>T) were novel and not listed in the BIC database. Two recurrent BRCA1 mutations (c.5266dupC and c.181T>G), previously described among Ashkenazi Jewish and Eastern European populations, were also found. Two unclassified variants (UV) were found, one of which was novel (BRCA2 c.4589A>G). Medical follow-up for mutation carriers was implemented. Our study is the first molecular investigation of the role of the BRCA genes in breast and ovarian cancer in Romania.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Predisposição Genética para Doença , Mutação/genética , Neoplasias Ovarianas/genética , Adulto , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Análise Mutacional de DNA , DNA de Neoplasias/genética , Família , Feminino , Genótipo , Humanos , Masculino , Programas de Rastreamento , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/epidemiologia , Reação em Cadeia da Polimerase , Polimorfismo Genético , Fatores de Risco , Romênia/epidemiologia
13.
Hum Immunol ; 64(12): 1152-9, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14630397

RESUMO

The major histocompatibility complex (MHC) class I related neonatal Fc receptor (FcRn) plays multiple roles, being involved in transporting immunoglobulin G (IgG) and protecting this antibody class from catabolism. The presence of this receptor was previously demonstrated in the lactating murine mammary gland. In the current study we have investigated FcRn expression in various histologic types of human breast carcinoma and lymph node metastases. We used immunohistochemical methods to demonstrate the presence of FcRn in epithelial cells, whereas this Fc receptor could not be detected in mammary gland endothelial cells. The presence of the receptor was also found in the metastasizing epithelial cells within the lymph nodes, and this provides a useful marker for their identification.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Genes MHC Classe I/imunologia , Glândulas Mamárias Humanas/patologia , Receptores Fc/biossíntese , Transporte Biológico , Neoplasias da Mama/imunologia , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/imunologia , Carcinoma Ductal de Mama/metabolismo , Células Endoteliais/imunologia , Células Endoteliais/metabolismo , Células Epiteliais/imunologia , Células Epiteliais/metabolismo , Feminino , Antígenos de Histocompatibilidade Classe I , Humanos , Imunoglobulina G/biossíntese , Imunoglobulina G/imunologia , Imuno-Histoquímica , Metástase Linfática , Glândulas Mamárias Humanas/imunologia , Glândulas Mamárias Humanas/metabolismo , Gravidez , Receptores Fc/imunologia
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