Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 13 de 13
Filtrar
1.
Cancers (Basel) ; 16(6)2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38539463

RESUMEN

Slovakia has one of the highest rates of colorectal cancer among the developed countries, ranking as the second highest in the incidence of this disease for men worldwide. Despite the significant burden on both quality of life and the healthcare system this disease imposes, data on molecular analysis of biomarkers in CRC-diagnosed patients is scarce. In our study, we analyzed confirmed CRC patients from the database of the National Cancer Institute (NCI) and evaluated the presence of 4 biomarkers in tumor tissues. Altogether, 83 FFPE tumor tissues from CRC patients listed in the NCI database were analyzed for microsatellite instability status, presence of BRAF and KRAS/NRAS mutations, and neoplastic cell percentage in tissue samples. We identified 4 MSI-high samples, 39 KRAS/NRAS mutations, and 5 BRAF p.V600E mutations, with one case of coexistence of all three markers in a single tumor sample. We also evaluated possible relationships between biomarkers, their coexistence, and the age and sex of the studied population.

2.
Biomed Pharmacother ; 165: 115179, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37481927

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is among the deadliest cancers worldwide, primarily due to its robust desmoplastic stroma and immunosuppressive tumor microenvironment (TME), which facilitate tumor progression and metastasis. In addition, fibrous tissue leads to sparse vasculature, high interstitial fluid pressure, and hypoxia, thereby hindering effective systemic drug delivery and immune cell infiltration. Thus, remodeling the TME to enhance tumor perfusion, increase drug retention, and reverse immunosuppression has become a key therapeutic strategy. In recent years, targeting epigenetic pathways has emerged as a promising approach to overcome tumor immunosuppression and cancer progression. Moreover, the progress in nanotechnology has provided new opportunities for enhancing the efficacy of conventional and epigenetic drugs. Nano-based drug delivery systems (NDDSs) offer several advantages, including improved drug pharmacokinetics, enhanced tumor penetration, and reduced systemic toxicity. Smart NDDSs enable precise targeting of stromal components and augment the effectiveness of immunotherapy through multiple drug delivery options. This review offers an overview of the latest nano-based approaches developed to achieve superior therapeutic efficacy and overcome drug resistance. We specifically focus on the TME and epigenetic-targeted therapies in the context of PDAC, discussing the advantages and limitations of current strategies while highlighting promising new developments. By emphasizing the immense potential of NDDSs in improving therapeutic outcomes in PDAC, our review paves the way for future research in this rapidly evolving field.


Asunto(s)
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Nanomedicina , Sistema de Administración de Fármacos con Nanopartículas , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patología , Microambiente Tumoral/genética , Neoplasias Pancreáticas
3.
J Vis Exp ; (195)2023 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-37306424

RESUMEN

Tumor organoids are three-dimensional (3D) ex vivo tumor models that recapitulate the biological key features of the original primary tumor tissues. Patient-derived tumor organoids have been used in translational cancer research and can be applied to assess treatment sensitivity and resistance, cell-cell interactions, and tumor cell interactions with the tumor microenvironment. Tumor organoids are complex culture systems that require advanced cell culture techniques and culture media with specific growth factor cocktails and a biological basement membrane that mimics the extracellular environment. The ability to establish primary tumor cultures highly depends on the tissue of origin, the cellularity, and the clinical features of the tumor, such as the tumor grade. Furthermore, tissue sample collection, material quality and quantity, as well as correct biobanking and storage are crucial elements of this procedure. The technical capabilities of the laboratory are also crucial factors to consider. Here, we report a validated SOP/protocol that is technically and economically feasible for the culture of ex vivo tumor organoids from fresh tissue samples of pancreatic adenocarcinoma origin, either from fresh primary resected patient donor tissue or patient-derived xenografts (PDX). The technique described herein can be performed in laboratories with basic tissue culture and mouse facilities and is tailored for wide application in the translational oncology field.


Asunto(s)
Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Animales , Ratones , Bancos de Muestras Biológicas , Fibroblastos , Organoides , Microambiente Tumoral , Neoplasias Pancreáticas
4.
J Cardiothorac Surg ; 18(1): 164, 2023 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-37118814

RESUMEN

BACKGROUND: Pericardial effusions with its potential life threatening progression towards cardiac tamponade have to be often managed with surgical intervention. In our case study we describe a complication after a common surgical procedure which has only scarce literature mentions. CASE PRESENTATION: We present a case of a 22-year-old male patient who underwent subxiphoidal pericardial fenestration, due to symptomatic pericardial effusion with the Chamberlain procedure and biopsy of enlarged mediastinal lymph nodes. The histology report confirmed classical Hodgkin lymphoma and subsequently the patient underwent oncological treatment. Later on he was admitted to the hospital with dyspnoea and chest pain. The initial examinations stated a suspicion for intrathoracic tumour arising from the pericardium or liver. Further investigation revealed symptomatic intrathoracic liver herniation for which the patient underwent laparoscopic surgery with the mobilisation of liver and placement of a perforated Parietene™ composite mesh. CONCLUSION: The purpose of this case report is to describe a rare complication after pericardial fenestration with its potential clinical implications.


Asunto(s)
Taponamiento Cardíaco , Derrame Pericárdico , Masculino , Humanos , Adulto Joven , Adulto , Pericardio/patología , Taponamiento Cardíaco/etiología , Derrame Pericárdico/etiología , Mediastino/patología , Hígado/patología
5.
Materials (Basel) ; 16(2)2023 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-36676548

RESUMEN

Formability and its prediction of high-strength steels is an important research subject for forming specialists and researchers in this field. Springback and its accurate prediction of high-strength steels are very common issues in metal forming processes. In this article, the impact of blank holding force and friction on the parts springback made of dual-phase steel was studied. Numerical predictions of the springback effect were conducted using nine combinations of yield criteria and hardening rules. Results from experiments were evaluated and compared with results from numerical simulations. The use of lower blank holding forces and PE foil can reduce springback by a significant amount. Numerical simulations where the Yoshida-Uemori hardening rule was applied produced more accurate springback prediction results compared to simulations that used Krupkowski and Hollomon's isotropic hardening rules in number of cases.

6.
Materials (Basel) ; 17(1)2023 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-38204064

RESUMEN

The body constitutes the largest proportion of the total vehicle weight. Recently, increasing efforts have been made towards reducing its weight and improving its crashworthiness. By reducing its weight, fuel consumption will be reduced, and this will also translate into lower CO2 emissions. In terms of safety, vehicle body components use high strength steel which can absorb a substantial amount of impact energy. The present study pays attention to DP 600 and TRIP 400/700 stress-strain characteristics at quasi-static strain rates. The stress-strain characteristics of absorption capacity, stiffness, and deformation resistance force were investigated experimentally by tensile tests, three-point bending tests, and numerical simulations. The results indicate the potential for increasing the absorption capacity, stiffness, and deformation resistance force of the vehicle body's deformable steel components. The present study verified the possibility of replacing physical testing with numerical simulation. A reasonably satisfactory agreement between the experimentally determined stress-strain characteristics and the numerical simulation was achieved, which can reduce the development time of deformable vehicle body components, reduce costs and optimize the selection of materials. The results extend the state of knowledge on the deformation characteristics of high-strength materials and contribute to the optimization of body components in terms of passive safety and weight.

7.
Int J Mol Sci ; 23(4)2022 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-35216235

RESUMEN

Due to abundant stroma and extracellular matrix, accompanied by lack of vascularization, pancreatic ductal adenocarcinoma (PDAC) is characterized by severe hypoxia. Epigenetic regulation is likely one of the mechanisms driving hypoxia-induced epithelial-to-mesenchymal transition (EMT), responsible for PDAC aggressiveness and dismal prognosis. To verify the role of DNA methylation in this process, we assessed gene expression and DNA methylation changes in four PDAC cell lines. BxPC-3, MIA PaCa-2, PANC-1, and SU.86.86 cells were exposed to conditioned media containing cytokines and inflammatory molecules in normoxic and hypoxic (1% O2) conditions for 2 and 6 days. Cancer Inflammation and Immunity Crosstalk and Human Epithelial to Mesenchymal Transition RT² Profiler PCR Arrays were used to identify top deregulated inflammatory and EMT-related genes. Their mRNA expression and DNA methylation were quantified by qRT-PCR and pyrosequencing. BxPC-3 and SU.86.86 cell lines were the most sensitive to hypoxia and inflammation. Although the methylation of gene promoters correlated with gene expression negatively, it was not significantly influenced by experimental conditions. However, DNA methyltransferase inhibitor decitabine efficiently decreased DNA methylation up to 53% and reactivated all silenced genes. These results confirm the role of DNA methylation in EMT-related gene regulation and uncover possible new targets involved in PDAC progression.


Asunto(s)
Carcinoma Ductal Pancreático/genética , Metilación de ADN/genética , Transición Epitelial-Mesenquimal/genética , Regulación Neoplásica de la Expresión Génica/genética , Expresión Génica/genética , Neoplasias Pancreáticas/genética , Biomarcadores de Tumor/genética , Carcinoma Ductal Pancreático/patología , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Epigénesis Genética/genética , Humanos , Neoplasias Pancreáticas/patología , Pronóstico , Neoplasias Pancreáticas
8.
BMC Surg ; 22(1): 39, 2022 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-35114982

RESUMEN

BACKGROUND: Congenital abnormalities are not very common and are even rarer when two or more are combined. Congenital malformation of the superior mesenteric vein may not affect normal development, or it may lead to moderate or even severe symptoms. In combination with intestinal malrotation, however, it may lead to the need for surgical intervention in the early years of life. CASE PRESENTATION: We present the case of a 22-year-old patient who had been diagnosed with iron deficiency anaemia at the age of two months. As a result of the absence of the proximal section of the superior mesenteric vein, the patient has always needed iron supplements and an occasional erythrocyte transfusion. This has resulted from the formation of collaterals throughout the small bowel, causing chronic blood loss with its clinical manifestation. Although, there are some congenital abnormalities of the superior mesenteric vein, the absence of the superior mesenteric vein is rare, and in this case the clinical course was quite severe. Therefore, we planned bypass surgery for this patient to reduce the duodenal collaterals and resolve the persistent anaemia caused by chronic blood loss from the duodenum. We successfully performed the surgery consisting of the formation of anastomosis between the large collateral vein from the distal end of the superior mesenteric vein and the anterior inferior pancreaticoduodenal vein. CONCLUSION: The purpose of this case report is to describe the rare anatomical malformation of the superior mesenteric vein accompanied by intestinal malrotation, with its potential clinical implications regarding symptoms, clinical presentation, and the impact on potential surgery planning.


Asunto(s)
Anomalías del Sistema Digestivo , Vólvulo Intestinal , Adulto , Humanos , Lactante , Vólvulo Intestinal/diagnóstico por imagen , Vólvulo Intestinal/cirugía , Intestino Delgado , Venas Mesentéricas/diagnóstico por imagen , Venas Mesentéricas/cirugía , Vena Porta , Adulto Joven
9.
Cell Tissue Bank ; 22(1): 39-46, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32862394

RESUMEN

Mesenchymal stem cells (MSCs) are multi-potent cells characterized by long term self-renewal and by potential for differentiation into cells of different mesenchymal tissue types such as fibroblasts, osteocytes, chondrocytes, and adipocytes. Their unique properties offer broad therapeutic potentials. Bone marrow has been used as the most common MSCs source, but it is gradually going to be replaced by adipose tissue which showed to contain more MSCs per unit than the bone marrow and clinical application of MSCs procured from the adipose tissue have been demonstrating at least similar results. Post-burn scars result frequently in severe both functional and aesthetic impairments in restitution and rehabilitation periods of the burn disease. Despite extensive research in the last decades, the exact mechanisms of scar formation remains unclear. The development of post-burn scars is influenced by multiple factors such as initial depth of the burn, methods of burn wound therapy, duration of the open wound until final wound closure, burn wound infection, genetic predisposition, and many others in both acute and rehabilitation periods. The aim of this study was to point out versatility of the implementation of this method with respect to different types of scars (atrophic scars, hypertrophic scars, keloids). Autologous adipose tissue derived MSCs were applied to post-burn scars in all 8 patients undergoing surgical scar reconstructions at the Department of Burns and Reconstructive Surgery of the University Hospital in Bratislava. The study was approved by Ethical Committee of Ruzinov Hospital. The procedures used for scar reconstructions included dermabrasion, scar excisions, contractures corrections and local plasties combined by lipografting of lipoaspirate containing parenchymal adipocytes and stromal vascular fraction including MSCs, or application of separated autologous MSCs isolated from lipoaspirates. Based on desired result one of these MSCs application methods was selected depending on characteristics of reconstructed scar and required volume of transferred fat. Isolation of MSCs following procurement was provided by the Central Tissue Bank cell culture laboratory which is one of the parts of the burn department. The average time of scars duration was 79 months, ranging from 6 to 216 months. The postburns scars were assessed clinically according to Vancouver Scar Scale (VSS) prior to surgery, including photo documentation, and re-evaluated after 6 months following MSCs application. As the results have shown, the average VSS score before treatment was 7.88 points ranging from 4 to 11 points. The average VSS 6 months after surgical procedure and MSCs application was 2.34 points ranging from 1 to 4 points. According to the results obtained, the favourable effect of adipose tissue derived autologous MSCs application on scar remodelling following surgical reconstruction of post-burn scars could be promising.


Asunto(s)
Células Madre Mesenquimatosas , Cicatriz Hipertrófica/patología , Fibroblastos , Humanos
10.
Materials (Basel) ; 13(5)2020 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-32182783

RESUMEN

Exterior car-body parts are made of steel or aluminum sheets. Their formability and appearance after painting depends not only on the mechanical properties but also on their surface texture. The surface roughness characteristics, the roughness average Ra and the peak count Pc per centimeter depend on the texture of rolling mill's finishing rollers, their wear and the degree of removal by the rolling mill. The research was carried out on heat-treated finishing rollers on the surface of which a controlled texture was created by changing the electro-discharge texturing (EDT) parameters. Parameters and the number of electro-discharge texturing experiments were optimized using full four-factor experiment techniques at the upper and lower levels of the parameters in the form of 24. The significance of the impact of individual EDT parameters and their interactions was identified based on the variance results. The ANOVA variance analysis results confirmed that the roughness Ra and the peak count Pc depend primarily on peak current (Ip), discharge peak voltage (Up), pulse on time (Pont) and pulse off time (Pofft). Optimization of the effect of the above parameters on the target roughness RaT,FR values and the peak count PcT,FR of finishing rollers was performed by the response surface methodology (RSM). Obtained regression models describe relationships between the input parameters of the electro-discharge texturing of finishing rollers and the output characteristics of the RaT,FR and the PcT,FR texture to a very high degree. The reliability of the electro-discharge texturing process of working rollers was assessed using the process capability index Cpk.

11.
BMC Surg ; 19(1): 62, 2019 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-31200669

RESUMEN

BACKGROUND: Tumor lysis syndrome is an unusual metabolic emergency in solid tumors. Perioperative occurrence of this syndrome is extremely rare but may have fatal consequences if not detected and treated on time. CASE REPORT: We report a 19-year patient with testicular germ cell tumor after first line chemotherapy with giant growing teratoma syndrome in retroperitoneum. He underwent radical resection, however, perioperatively, a fatal case of heart failure due to unrecognized intraoperative tumor lysis syndrome developed. CONCLUSION: Surgeons, anesthesiologists and oncologists should be aware of this complication in order to be prepared for such an emergency.


Asunto(s)
Neoplasias de Células Germinales y Embrionarias/tratamiento farmacológico , Neoplasias Retroperitoneales/cirugía , Teratoma/cirugía , Neoplasias Testiculares/tratamiento farmacológico , Síndrome de Lisis Tumoral/etiología , Cisplatino/administración & dosificación , Humanos , Neoplasias Pulmonares/cirugía , Metástasis Linfática , Masculino , Orquiectomía , Pronóstico , Espacio Retroperitoneal , Adulto Joven
12.
BMC Cancer ; 18(1): 848, 2018 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-30143021

RESUMEN

BACKGROUND: Efficiency of colorectal carcinoma treatment by chemotherapy is diminished as the resistance develops over time in patients. The same holds true for 5-fluorouracil, the drug used in first line chemotherapy of colorectal carcinoma. METHODS: Chemoresistant derivative of HT-29 cells was prepared by long-term culturing in increasing concentration of 5-fluorouracil. Cells were characterized by viability assays, flow cytometry, gene expression arrays and kinetic imaging. Immunomagnetic separation was used for isolation of subpopulations positive for cancer stem cells-related surface markers. Aldehyde dehydrogenase expression was attenuated by siRNA. In vivo studies were performed on SCID/bg mice. RESULTS: The prepared chemoresistant cell line labeled as HT-29/EGFP/FUR is assigned with different morphology, decreased proliferation rate and 135-fold increased IC50 value for 5-fluorouracil in comparison to parental counterparts HT-29/EGFP. The capability of chemoresistant cells to form tumor xenografts, when injected subcutaneously into SCID/bg mice, was strongly compromised, however, they formed distant metastases in mouse lungs spontaneously. Derived cells preserved their resistance in vitro and in vivo even without the 5-fluorouracil selection pressure. More importantly, they were resistant to cisplatin, oxaliplatin and cyclophosphamide exhibiting high cross-resistance along with alterations in expression of cancer-stem cell markers such as CD133, CD166, CD24, CD26, CXCR4, CD271 and CD274. We also detected increased aldehyde dehydrogenase (ALDH) activity associated with overexpression of specific ALDH isoform 1A3. Its inhibition by siRNA approach partially sensitized cells to various agents, thus linking for the first time the ALDH1A3 and chemoresistance in colorectal cancer. CONCLUSION: Our study demonstrated that acquired chemoresistance goes along with metastatic and migratory phenotype and can be accompanied with increased activity of aldehyde dehydrogenase. We describe here the valuable model to study molecular link between resistance to chemotherapy and metastatic dissemination.


Asunto(s)
Aldehído Oxidorreductasas/genética , Neoplasias Colorrectales/genética , Resistencia a Antineoplásicos/genética , Adulto , Anciano , Animales , Neoplasias Colorrectales/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Células HT29 , Humanos , Masculino , Ratones , Persona de Mediana Edad , Metástasis de la Neoplasia , ARN Interferente Pequeño , Ensayos Antitumor por Modelo de Xenoinjerto
13.
BMC Surg ; 17(1): 34, 2017 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-28376753

RESUMEN

BACKGROUND: Limited data are available on the importance of routine lymphadenectomy of the hepatoduodenal ligament in the treatment of liver metastasis from colorectal cancer in the literature. METHODS: A single center retrospective cohort study was conducted to evaluate morbidity and long-term survival in patients who had undergone selective versus routine lymphadenectomy during surgery for colorectal liver metastasis. From January 2006 to December 2009, eighty-one patients undergoing radical resection due to liver metastasis from colorectal cancer were included. The combination of two surgical teams with different approaches to hepatoduodenal ligament lymphadenectomy at our institution allowed us to select two cohorts of patients undergoing selective or routine lymphadenectomy. RESULTS: No significant differences between the cohorts were found in age, American Society of Anesthesiology score or Fong's prognostic criteria. Patients with pN+ disease had significantly inferior survival compared to patients with pN0 disease (hazard ratio [HR] = 6.33, 95% CI 2.16-18.57, p = 0.0001). No significant difference in postoperative morbidity was observed in the group undergoing routine opposed to selective lymphadenectomy (13.63% vs. 8.69%, p = 0.36). There was no difference in long-term survival between the groups (HR = 0.90, 95% CI 0.52-1.58, p = 0.70). There were also no significant differences in the subgroup of patients with pN0 stage (HR = 1.17, 95% CI 0.6-2.11, p = 0.60). CONCLUSIONS: These data suggest that there is no survival benefit from the use of routine lymphadenectomy during surgery for colorectal liver metastasis, but these data should be confirmed in a prospective randomized study.


Asunto(s)
Neoplasias Colorrectales/patología , Neoplasias Hepáticas/secundario , Escisión del Ganglio Linfático/métodos , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Humanos , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...