Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 41
Filtrar
1.
Curr Issues Mol Biol ; 46(5): 4506-4518, 2024 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-38785541

RESUMO

The memory-enhancing activity of Matricaria chamomilla hydroalcoholic extract (MCE) is already being investigated by behavioral and biochemical assays in scopolamine-induced amnesia rat models, while the effects of scopolamine (Sco) on cerebral glucose metabolism are examined as well. Nevertheless, the study of the metabolic profile determined by an enriched MCE has not been performed before. The present experiments compared metabolic quantification in characteristic cerebral regions and behavioral characteristics for normal, only diseased, diseased, and MCE- vs. Galantamine (Gal)-treated Wistar rats. A memory deficit was induced by four weeks of daily intraperitoneal Sco injection. Starting on the eighth day, the treatment was intraperitoneally administered 30 min after Sco injection for a period of three weeks. The memory assessment comprised three maze tests. Glucose metabolism was quantified after the 18F-FDG PET examination. The right amygdala, piriform, and entorhinal cortex showed the highest differential radiopharmaceutical uptake of the 50 regions analyzed. Rats treated with MCE show metabolic similarity with normal rats, while the Gal-treated group shows features closer to the diseased group. Behavioral assessments evidenced a less anxious status and a better locomotor activity manifested by the MCE-treated group compared to the Gal-treated group. These findings prove evident metabolic ameliorative qualities of MCE over Gal classic treatment, suggesting that the extract could be a potent neuropharmacological agent against amnesia.

2.
Curr Issues Mol Biol ; 45(10): 7891-7914, 2023 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-37886942

RESUMO

Brown Adipose Tissue (BAT) is considered beneficial in diabetes and obesity, but it can also have negative effects such as its implication in tumours' pathogenesis and the development of Cancer-induced Cachexia. Since 18F-FDG PET/CT is a common molecular imaging modality used in cancer assessment, we aim to study the 18F-FDG BAT biodistribution in oncological patients and look for possible correlations between BAT activity and different malignancies as well as the patient's weight status. After analysing the total number of oncological 18F-FDG PET/CT scans between 2017 and 2021, we selected patients with active BAT. Based on their BMI, the selected patients were divided into nonobese (NO) vs. overweight and obese (OOB). OOB SUVmaxlean body mass(LBM) had the highest mean values in supraclavicular, latero-cervical, and paravertebral vs. mediastinal and latero-thoracic localisations in NO. BMI was positively correlated with latero-cervical and supraclavicular SUVmax(LBM) but negatively correlated with latero-thoracic and abdominal SUVmax(LBM). Considering the age of the patients, SUVmax(LBM) decreases in the latero-cervical, paravertebral, and abdominal regions. In addition, the males presented lower SUVmax(LBM) values. SUVmax(LBM) was not affected by the treatment strategy or the oncological diagnosis. To conclude, it is mandatory to take into consideration the BAT particularities and effects on weight status in order to optimise the clinical management of oncological patients.

3.
Biomedicines ; 12(1)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38255256

RESUMO

Recent research has suggested that one novel mechanism of action for anti-obesity medications is to stimulate the activation of brown adipose tissue (BAT). 18FDG PET/CT remains the gold standard for defining and quantifying BAT. SUVmax is the most often used quantification tool in clinical practice. However, this parameter does not reflect the entire BAT volume. As a potential method for precisely evaluating BAT, we have utilised metabolic tumour volume (MTV) and total lesion glycolysis (TLG) to answer the question: Are MTV and TLG accurate in quantifying the intensity of BAT activation? After analysing the total number of oncological 18F-FDG PET/CT scans between 2021-2023, we selected patients with active BAT. Based on the BAT SUVmax, the patients were divided into BAT-moderate activation (MA) vs. BAT-high activation (HA). Furthermore, we statistically analysed the accuracy of TLG and MTV in assessing BAT activation intensity. The results showed that both parameters increased their predictive value regarding BAT activation, and presented a significantly high sensitivity and specificity for the correct classification of BAT activation intensity. To conclude, these parameters could be important indicators with increased accuracy for classifying BAT expression, and could bring additional information about the volume of BAT to complement the limitations of the SUVmax.

4.
Diagnostics (Basel) ; 14(13)2024 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-39001288

RESUMO

BACKGROUND: Technology allows us to predict a histopathological diagnosis, but the high costs prevent the large-scale use of these possibilities. The current liberal indication for surgery in benign thyroid conditions led to a rising frequency of incidental thyroid carcinoma, especially low-risk papillary micro-carcinomas. METHODS: We selected a cohort of 148 patients with thyroid nodules by ultrasound characteristics and investigated them by fine needle aspiration cytology (FNAC)and prospective BRAF collection for 70 patients. Also, we selected 44 patients with thyroid nodules using semi-quantitative functional imaging with an oncological, 99mTc-methoxy-isobutyl-isonitrile (99mTc-MIBI) radiotracer. RESULTS: Following a correlation with final histopathological reports in patients who underwent thyroidectomy, we introduced the results in a machine learning program (AI) in order to obtain a pattern. For semi-quantitative functional visual pattern imaging, we found a sensitivity of 33%, a specificity of 66.67%, an accuracy of 60% and a negative predicting value (NPV) of 88.6%. For the wash-out index (WOind), we found a sensitivity of 57.14%, a specificity of 50%, an accuracy of 70% and an NPV of 90.06%.The results of BRAF in FNAC included 87.50% sensitivity, 75.00% specificity, 83.33% accuracy, 75.00% NPV and 87.50% PPV. The prevalence of malignancy in our small cohort was 11.4%. CONCLUSIONS: We intend to continue combining preoperative investigations such as molecular detection in FNAC, 99mTc-MIBI scanning and AI training with the obtained results on a larger cohort. The combination of these investigations may generate an efficient and cost-effective diagnostic tool, but confirmation of the results on a larger scale is necessary.

5.
J Mater Chem B ; 12(15): 3659-3675, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38530751

RESUMO

The demand for tailored, disease-adapted, and easily accessible radiopharmaceuticals is one of the most persistent challenges in nuclear imaging precision medicine. The aim of this work was to develop two multimodal radiotracers applicable for both SPECT and PET techniques, which consist of a gold nanoparticle core, a shell involved in radioisotope entrapment, peripherally placed targeting molecules, and biocompatibilizing polymeric sequences. Shell decoration with glucosamine units located in sterically hindered molecular environments is expected to result in nanoparticle accumulation in high-glucose-consuming areas. Gold cores were synthesized using the Turkevich method, followed by citrate substitution with linear PEG α,ω-functionalized with thiol and amine groups. The free amine groups facilitated the binding of branched polyethyleneimine through an epoxy ring-opening reaction by using PEG α,ω-diglycidyl ether as a linker. Afterwards, the glucose-PEG-epoxy prepolymer has been grafted onto the surface of AuPEG-PEI conjugates. Finally, the AuPEG-PEI-GA conjugates were radiolabeled with 99mTc or 68Ga. Instant thin-layer chromatography was used to evaluate the radiolabeling yield. The biocompatibility of non-labeled and 99mTc or 68Ga labeled nanoparticles was assessed on normal fibroblasts. The 99mTc complexes remained stable for over 22 hours, while the 68Ga containing ones revealed a slight decrease in stability after 1 hour.


Assuntos
Ouro , Nanopartículas Metálicas , Ouro/química , Radioisótopos de Gálio , Nanopartículas Metálicas/química , Tomografia Computadorizada de Emissão de Fóton Único , Tomografia por Emissão de Pósitrons , Glucose , Aminas
6.
Pharmaceuticals (Basel) ; 16(12)2023 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-38139806

RESUMO

The high energy of α emitters, and the strong linear energy transfer that goes along with it, lead to very efficient cell killing through DNA damage. Moreover, the degree of oxygenation and the cell cycle state have no impact on these effects. Therefore, α radioisotopes can offer a treatment choice to individuals who are not responding to ß- or gamma-radiation therapy or chemotherapy drugs. Only a few α-particle emitters are suitable for targeted alpha therapy (TAT) and clinical applications. The majority of available clinical research involves 225Ac and its daughter nuclide 213Bi. Additionally, the 225Ac disintegration cascade generates γ decays that can be used in single-photon emission computed tomography (SPECT) imaging, expanding the potential theranostic applications in nuclear medicine. Despite the growing interest in applying 225Ac, the restricted global accessibility of this radioisotope makes it difficult to conduct extensive clinical trials for many radiopharmaceutical candidates. To boost the availability of 225Ac, along with its clinical and potential theranostic applications, this review attempts to highlight the fundamental physical properties of this α-particle-emitting isotope, as well as its existing and possible production methods.

7.
Diagnostics (Basel) ; 12(4)2022 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-35453992

RESUMO

Personalized diagnosis can save unnecessary thyroid surgeries, in cases of indeterminate thyroid nodules, when clinicians tend to aggressively treat all these patients. Personalized diagnosis benefits from a combination of imagery and molecular biomarkers, as well as artificial intelligence algorithms, which are used more and more in our timeline. Functional imaging diagnosis such as SPECT, PET, or fused images (SPECT/CT, PET/CT, PET/MRI), is exploited at maximum in thyroid nodules, with a long history in the past and a bright future with many suitable radiotracers that could properly contribute to diagnosing malignancy in thyroid nodules. In this way, patients will be spared surgery complications, and apparently more expensive diagnostic workouts will financially compensate each patient and also the healthcare system. In this review we will summarize essential available diagnostic tools for malignant and benignant thyroid nodules, beginning with functional imaging, molecular analysis, and combinations of these two and other future strategies, including AI or NIS targeted gene therapy for thyroid carcinoma diagnosis and treatment as well.

8.
J Neuroendocrinol ; 34(4): e13109, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35304807

RESUMO

Peptide receptor radionuclide therapy (177 Lu-DOTATATE) causes DNA strand breaks and has been validated for well-differentiated neuroendocrine tumor treatment. Poly-(ADP-ribose)-polymerase inhibitors have also been used for malignant tumors with deficient DNA repair. We aimed to determine whether the poly-(ADP-ribose)-polymerase inhibitor fluzoparib could enhance the anti-tumor effects of 177 Lu-DOTATATE in neuroendocrine tumor cells and xenografts. The neuroendocrine characteristics of NCI-H727 bronchial carcinoid cells were evaluated by immunofluorescence staining. The synergistic effects of fluzoparib and 177 Lu-DOTATATE were evaluated by cell proliferation and flow cytometry assays. Tumor response and the side effects of combination therapy were also assessed in xenograft mice treated with 77 Lu-DOTATATE and fluzoparib alone or in combination. Somatostatin receptors were specifically expressed in NCI-H727 cells and tumor xenografts. 177 Lu-DOTATATE (22.20 MBq mL-1 ) and fluzoparib (50 µm) inhibited cell proliferation by 16.6% and 35.6%, respectively, compared to 73.2% in cells treated with their combination. Tumor cell proliferation was significantly suppressed by 177 Lu-DOTATATE (22.20 MBq mL-1 , 4.4-fold) and fluzoparib (50 µm, 2.1-fold). 177 Lu-DOTATATE caused cell cycle arrest mainly at G1 phase, whereas fluzoparib caused arrest at G2/M phase, and combined treatment with both agents caused cell cycle arrest at G1 phase, similar to 177 Lu-DOTATATE alone. The volume of tumor xenografts was reduced by 18.6% in mice receiving combined treatment, compared to 4.9% and 11.4% in mice treated with 177 Lu-DOTATATE or fluzoparib alone. Fluzoparib can potentiate the anti-tumor effect of 177 Lu-DOTATATE in NCI-H727 cells in a synergistic manner by arresting the cell cycle at G1 phase. Further preclinical and clinical studies are warranted to validate these findings.


Assuntos
Tumores Neuroendócrinos , Adenosina Difosfato Ribose , Animais , Humanos , Camundongos , Tumores Neuroendócrinos/tratamento farmacológico , Tumores Neuroendócrinos/metabolismo , Tumores Neuroendócrinos/radioterapia , Tomografia por Emissão de Pósitrons , Radioisótopos , Cintilografia , Compostos Radiofarmacêuticos/uso terapêutico , Receptores de Somatostatina/metabolismo
9.
Cancers (Basel) ; 14(12)2022 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-35740581

RESUMO

AIM: The need for predictive and prognostic biomarkers in colorectal carcinoma (CRC) brought us to an era where the use of artificial intelligence (AI) models is increasing. We investigated the expression of Claudin-7, a tight junction component, which plays a crucial role in maintaining the integrity of normal epithelial mucosa, and its potential prognostic role in advanced CRCs, by drawing a parallel between statistical and AI algorithms. METHODS: Claudin-7 immunohistochemical expression was evaluated in the tumor core and invasion front of CRCs from 84 patients and correlated with clinicopathological parameters and survival. The results were compared with those obtained by using various AI algorithms. RESULTS: the Kaplan-Meier univariate survival analysis showed a significant correlation between survival and Claudin-7 intensity in the invasive front (p = 0.00), a higher expression being associated with a worse prognosis, while Claudin-7 intensity in the tumor core had no impact on survival. In contrast, AI models could not predict the same outcome on survival. CONCLUSION: The study showed through statistical means that the immunohistochemical overexpression of Claudin-7 in the tumor invasive front may represent a poor prognostic factor in advanced stages of CRCs, contrary to AI models which could not predict the same outcome, probably because of the small number of patients included in our cohort.

10.
Pharmaceutics ; 14(2)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35214129

RESUMO

Immunotherapy represents a promising strategy for the treatment of cancer, which functions via the reprogramming and activation of antitumor immunity. However, adverse events resulting from immunotherapy that are related to the low specificity of tumor cell-targeting represent a limitation of immunotherapy's efficacy. The potential of nanotechnologies is represented by the possibilities of immunotherapeutical agents being carried by nanoparticles with various material types, shapes, sizes, coated ligands, associated loading methods, hydrophilicities, elasticities, and biocompatibilities. In this review, the principal types of nanovectors (nanopharmaceutics and bioinspired nanoparticles) are summarized along with the shortcomings in nanoparticle delivery and the main factors that modulate efficacy (the EPR effect, protein coronas, and microbiota). The mechanisms by which nanovectors can target cancer cells, the tumor immune microenvironment (TIME), and the peripheral immune system are also presented. A possible mathematical model for the cellular communication mechanisms related to exosomes as nanocarriers is proposed.

11.
Diagnostics (Basel) ; 12(12)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36553189

RESUMO

Brown adipose tissue (BAT) participates in the regulation of whole-body metabolism by producing a variety of adipokines. This study investigates into the BAT pattern and the clinical aspects of overweight and obese (OOB) vs. non-obese (NO) hyperparathyroidism (HPT) patients with the aim of assessing the impact of BAT and obesity on HPT. Parathyroid scans performed on 441 HPT patients between 2015 and 2020 were retrospectively analyzed in order to select the images with active BAT. Based on their BMI, the patients with active BAT were divided into OOB vs. NO. The results showed that BAT was present in cervical and supraclavicular regions, with a single localization especially among NO vs. multiple sites among OOB. The (total counts/pixels)BAT/(total counts/pixels)non-BAT ratio in the right cervical localization showed a significant difference between the groups with higher values in OOB. BMI, PTH, FT4, vitamin D, magnesium, creatinine, and urea had significant correlations with BAT ratios. The predictive values showed that right cervical ratios higher than 1.52 and right supraclavicular ratios lower than 1.15 indicated an increased probability of being OOB. The significant correlations between BAT activation in OOB vs. NO and HPT clinical parameters could be useful for developing potential treatments based on this tissue.

12.
Cancers (Basel) ; 14(19)2022 Oct 03.
Artigo em Inglês | MEDLINE | ID: mdl-36230757

RESUMO

Colorectal cancer is a major cause of cancer-related death worldwide and is correlated with genetic and epigenetic alterations in the colonic epithelium. Genetic changes play a major role in the pathophysiology of colorectal cancer through the development of gene mutations, but recent research has shown an important role for epigenetic alterations. In this review, we try to describe the current knowledge about epigenetic alterations, including DNA methylation and histone modifications, as well as the role of non-coding RNAs as epigenetic regulators and the prognostic and predictive biomarkers in metastatic colorectal disease that can allow increases in the effectiveness of treatments. Additionally, the intestinal microbiota's composition can be an important biomarker for the response to strategies based on the immunotherapy of CRC. The identification of biomarkers in mCRC can be enhanced by developing artificial intelligence programs. We present the actual models that implement AI technology as a bridge connecting ncRNAs with tumors and conducted some experiments to improve the quality of the model used as well as the speed of the model that provides answers to users. In order to carry out this task, we implemented six algorithms: the naive Bayes classifier, the random forest classifier, the decision tree classifier, gradient boosted trees, logistic regression and SVM.

13.
Diagnostics (Basel) ; 11(5)2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-34069605

RESUMO

Thyroid cancer (TC) represents a worldwide problem, the consistent growth of the incidence increment issues about management of risk factors and curative treatment. Updated statistical data are not complete in the North East region of Romania and need to be improved. Therefore, through this study, we aim to renew the existing data on thyroid cancer. We conducted a retrospective study covering a period of 10 years. Data were collected from a hospital information system (InfoWorld) between 2009 and 2019. Patients' age groups were stratified in relation with the age at the moment of the Chernobyl event. A database was obtained (Microsoft Excel) and statistical correlations were applied. In the studied period, 1159 patients were diagnosed: 968 females and 191 males, distributed by region, with the highest addressability in Iasi (529), followed by neighboring counties. Age distribution displayed that most of the thyroid cancers were in the range 4060 years old (50.94%), followed by 60-80 years old (32.41%). Most patients were diagnosed with papillary carcinoma 63.10%, then follicular 14.7%, medullary 6.74% and undifferentiated 1.02%. Romania was in the vicinity of the radioactive cloud at Chernobyl fallout, so we must deliberate whether the increased incidence of thyroid cancer in the age group 40-60 years is associated with radiogenicity (iodine 131) given the fact that over has 35 years and the half-life of other radioisotopes like Caesium-137 and Strontium -90 is completed.

14.
J Pers Med ; 11(10)2021 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-34683183

RESUMO

Although neuroendocrine tumours (NETs) are intensively studied, their diagnosis and consequently personalised therapy management is still puzzling due to their tumoral heterogeneity. In their theragnosis algorithm, receptor somatostatin scintigraphy takes the central place, the diagnosis receptor somatostatin analogue (RSA) choice depending on laboratory experience and accessibility. However, in all cases, the results depend decisively on correct radiotracer tumoral uptake quantification, where unfortunately there are still unrevealed clues and lack of standardization. We propose an improved method to quantify the biodistribution of gamma-emitting RSA, using tissular corrected uptake indices. We conducted a bi-centric retrospective study on 101 patients with different types of NETs. Three uptake indices obtained after applying new corrections to areas of interest drawn for the tumour and for three reference organs (liver, spleen and lung) were statistically analysed. For the corrected pathological uptake indices, the results showed a significant decrease in the error of estimating the occurrence of errors and an increase in the diagnostic predictive power for NETs, especially in the case of lung-referring corrected index. In conclusion, these results support the importance of corrected uptake indices use in the analysis of 99mTcRSA biodistribution for a better personalised diagnostic accuracy of NETs patients.

15.
Exp Ther Med ; 21(5): 535, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33815608

RESUMO

Cancer immunotherapy has shifted the paradigm in cancer treatment in recent years. Immune checkpoint blockage (ICB), the active cancer vaccination and chimeric antigen receptor (CAR) for T-cell-based adoptive cell transfer represent the main developments, achieving a surprising increased survival in patients included in clinical trials. In spite of these results, the current state-of-the-art immunotherapy has its limitations in efficacy. The existence of an interdisciplinary interface involving current knowledge in biology, immunology, bioengineering and materials science represents important progress in increasing the effectiveness of immunotherapy in cancer. Cutaneous melanoma remains a difficult cancer to treat, in which immunotherapy is a major therapeutic option. In fact, enhancing immunotherapy is possible using sophisticated biomedical nanotechnology platforms of organic or inorganic materials or engineering various immune cells to enhance the immune system. In addition, biological devices have developed, changing the approach to and treatment results in melanoma. In this review, we present different modalities to modulate the immune system, as well as opportunities and challenges in melanoma treatment.

16.
World J Nucl Med ; 19(4): 417-420, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33623513

RESUMO

Gastrin-secreting tumors, hypergastrinemia and severe ulcer disease form the trademarks of Zollinger-Ellison syndrome (ZES). We report a case of gastrinoma, in a patient who was misdiagnosed for almost five years. The case emphsizes the the special role of functional imaging in the personalized approach to the patient with suggestive symptomatology for NETs. Taking into account that in 80 to 100% of cases of gastroenteropancreatic (GEP) NETs are expressing somatostatin receptors, the functional imaging with radiolabeled somatostatin analogues can be used in order to improve its diagnosis, respectively the treatment of GEP NETs. In the approach to the patient with tremendous digestive symptomatology, physicians from different specialties should evaluate NETs specific markers and then insist on structural-functional complementarity, avoiding the waste of time and high cost of repeated structural investigations. The conclusion of our study is that functional imaging is mandatory in the diagnostic algorithm of gastrinoma.

17.
Nucl Med Commun ; 41(7): 601-617, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32404645

RESUMO

BACKGROUND/OBJECTIVE: Data regarding the nephrotoxicity of the peptide receptor radionuclide therapy (PRRT) with Yttrium- and Lutetium-radiolabeled somatostatin analogs (RSA) are inconclusive. We aimed to evaluate the short- and long-term nephrotoxicity following PRRT usage in patients with all types of neuroendocrine tumors (NETs). METHODS: A systematic review of observational studies reporting data about nephrotoxicity after treatment with Yttrium and Lutetium RSA was performed. Data on serum creatinine, creatinine clearance, glomerular filtration rate (GFR) and need for renal replacement therapy were compiled. We included patients with progressive, inoperable symptomatic G1, G2 and G3 different types of NETs. After searching in three electronic databases PubMed, Scopus and the Cochrane Library, from 1 January 1978 to November 2018, data were extracted and summarized using a random-effects model. RESULTS: The final analysis included 34 studies, comprising 5386 participants, enrolling patients with G1, G2, G3 NETs and a follow-up from 12 up to 191 months. Compared with renal function before treatment, measured/estimated glomerular filtration rate (m/eGFR) values changed after PRRT, with a mean annual decrease following PRRT between 2 and 4 mL/min/1.73 m suggesting different grades of nephrotoxicity after PRRT. When compared, Y-RSA and the Y-RSA-Lu-RSA combination are associated with a higher m/eGFR decline compared to Lu-RSA alone. CONCLUSIONS: PRRT can be followed by potentially serious long-term nephrotoxicity, despite kidney protection. The use of the quantified renal function combined with a long follow-up period and personalized dosimetry-based PRRT can reduce nephrotoxicity, in order to use the whole PRRT potential in the management of NETs.


Assuntos
Rim/efeitos da radiação , Lutécio/efeitos adversos , Tumores Neuroendócrinos/radioterapia , Radioisótopos/efeitos adversos , Insuficiência Renal/etiologia , Somatostatina/efeitos adversos , Somatostatina/química , Radioisótopos de Ítrio/efeitos adversos , Humanos , Marcação por Isótopo , Lutécio/uso terapêutico , Radioisótopos/uso terapêutico , Radioisótopos de Ítrio/uso terapêutico
18.
Sci Rep ; 10(1): 6591, 2020 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-32313258

RESUMO

The paper aims to investigate the cytotoxic effect on tumor cells of irradiated AuNPs in green light and subsequently functionalized with HS-PEG-NH2. The toxicity level of gold conjugates after their functionalization with DOX and TAT peptide was also evaluated. The AuNPs were prepared using the modified Turkevich method and exposed to visible light at a wavelength of 520 nm prior their PEGylation. The optical properties were analyzed by UV-vis spectroscopy, the surface modification was investigated using FTIR and XPS spectroscopies and their sizes and morphologies were evaluated by TEM and DLS techniques. DOX and TAT peptide were linked to the surface of PEGylated AuNPs by reacting their amino groups with glycidyloxypropyl of PEGylated DOX or TAT conjugates under mild conditions at room temperature and in the presence of ethanol as catalyst. The conjugates containing DOX or DOX and TAT have been characterized by fluorescence and FTIR techniques. The changes of electrochemical features were observed using cyclic voltammetry, suggesting a better stability of irradiated nanoparticles. By mass spectrometry it was confirmed that the compounds of interest were obtained. The cell viability test showed that irradiated and non-irradiated nanoparticles coated with PEG are not toxic in normal cells. Tumor cell viability analysis showed that the PEGylated nanoparticles modified with DOX and TAT peptide were more effective than pristine DOX, indicating cytotoxicity up to 10% higher than non-irradiated ones.


Assuntos
Doxorrubicina/farmacologia , Produtos do Gene tat/farmacologia , Nanopartículas Metálicas/química , Osteossarcoma/tratamento farmacológico , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/química , Produtos do Gene tat/química , Ouro/química , Humanos , Osteossarcoma/genética , Osteossarcoma/patologia , Peptídeos/química , Peptídeos/farmacologia , Polietilenoglicóis/química , Polietilenoglicóis/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
19.
Front Oncol ; 10: 526850, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33330019

RESUMO

Noncoding RNAs (ncRNAs) include a diverse range of RNA species, including microRNAs (miRNAs) and long noncoding RNAs (lncRNAs). MiRNAs, ncRNAs of approximately 19-25 nucleotides in length, are involved in gene expression regulation either via degradation or silencing of the messenger RNAs (mRNAs) and have roles in multiple biological processes, including cell proliferation, differentiation, migration, angiogenesis, and apoptosis. LncRNAs, which are longer than 200 nucleotides, comprise one of the largest and most heterogeneous RNA families. LncRNAs can activate or repress gene expression through various mechanisms, acting alone or in combination with miRNAs and other molecules as part of various pathways. Until recently, most research has focused on individual lncRNA and miRNA functions as regulators, and there is limited available data on ncRNA interactions relating to the tumor growth, metastasis, and therapy of cancer, acting either on mRNA alone or as competing endogenous RNA (ceRNA) networks. Triple-negative breast cancer (TNBC) represents approximately 10%-20% of all breast cancers (BCs) and is highly heterogenous and more aggressive than other types of BC, for which current targeted treatment options include hormonotherapy, PARP inhibitors, and immunotherapy; however, no targeted therapies for TNBC are available, partly because of a lack of predictive biomarkers. With advances in proteomics, new evidence has emerged demonstrating the implications of dysregulation of ncRNAs in TNBC etiology. Here, we review the roles of lncRNAs and miRNAs implicated in TNBC, including their interactions and regulatory networks. Our synthesis provides insight into the mechanisms involved in TNBC progression and has potential to aid the discovery of new diagnostic and therapeutic strategies.

20.
Materials (Basel) ; 12(9)2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31075912

RESUMO

The Terahertz's wavelength is located between the microwave and the infrared region of the electromagnetic spectrum. Because it is non-ionizing and non-invasive, Terahertz (THz)-based detection represents a very attractive tool for repeated assessments, patient monitoring, and follow-up. Cancer acts as the second leading cause of death in many regions, and current predictions estimate a continuous increasing trend. Of all types of tumors, digestive cancers represent an important percentage and their incidence is expected to increase more rapidly than other tumor types due to unhealthy lifestyle habits. Because it can precisely differentiate between different types of molecules, depending on water content, the information obtained through THz-based scanning could have several uses in the management of cancer patients and, more importantly, in the early detection of different solid tumors. The purpose of this manuscript is to offer a comprehensive overview of current data available on THz-based detection for digestive cancers. It summarizes the characteristics of THz waves and their interaction with tissues and subsequently presents available THz-based technologies (THz spectroscopy, THz-tomography, and THZ-endoscope) and their potential for future clinical use. The third part of the review is focused on highlighting current in vitro and in vivo research progress in the field, for identifying specific digestive cancers known as oral, esophageal, gastric, colonic, hepatic, and pancreatic tumors.

SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa