Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 8 de 8
Filter
Add more filters








Publication year range
1.
Heliyon ; 10(17): e36981, 2024 Sep 15.
Article in English | MEDLINE | ID: mdl-39281487

ABSTRACT

This paper demonstrates the potential of Raman spectroscopy for differentiating neoplastic from non-neoplastic colon tumors, obtained with the CAM (chicken chorioallantoic membrane) model. For the CAM model two human cell lines were used to generate two types of tumors, the RKO cell line for neoplastic colon tumors and the NCM460 cell line for non-neoplastic colon tumors. The Raman spectra were acquired with a 785 nm excitation laser. The measured Raman spectra from the CAM samples (n = 14) were processed with several methods for baseline correction and to remove artifacts. The corrected spectra were analyzed with PCA (principal component analysis). Additionally, machine learning based algorithms were used to create a model capable of classifying neoplastic and non-neoplastic tumors. The principal component scores showed a clear differentiation between neoplastic and non-neoplastic colon tumors. The classification model had an accuracy of 93 %. Thus, a complete methodology to process and analyze Raman spectra was validated, using a rapid, accessible, and well-established tumor model that mimics the human tumor pathology with minor ethical concerns.

4.
Phys Med Biol ; 58(16): 5433-48, 2013 Aug 21.
Article in English | MEDLINE | ID: mdl-23877320

ABSTRACT

This work aims to contribute to the study of the radiation dose distribution delivered to the hands of medical staff members during a general computed tomographic (CT) fluoroscopic guided procedure. In this study, both Monte Carlo simulations and measurements were performed. For free-in-air and computed tomography dose index (CTDI) body phantom measurements, a standard pencil ionization chamber (IC) 100 mm long was used. The CT scanner model was implemented using MCNPX (Monte Carlo N-Particle eXtended) and was successfully validated by comparing the simulated results with measurements. Subsequently, CT images of a hand, together with an anthropomorphic phantom, were voxelized and used with the MCNPX code for dose calculations. The hand dose distribution study was performed both by using thermo-luminescent detector measurements and Monte Carlo simulations. The validated simulation tool provides a new perspective for detailed investigations of CT-irradiation scenarios. Simulations show that there is a strong dose gradient, namely the even zones of the hand that are in precise vicinity to the x-ray beam only receive about 4% of the maximum dose delivered to adjacent areas which are directly exposed to the primary x-ray beam. Finally, the scatter contribution of the patient was also studied through MC simulations. The results show that for directly exposed parts of the hand surface, the dose is reduced by the body of the patient (due to the shielding), whereas the dose is increased by scattered radiation from the patient for parts of the skin that receive scattered radiation only.


Subject(s)
Fluoroscopy/instrumentation , Hand , Health Personnel , Phantoms, Imaging , Radiometry/instrumentation , Humans , Monte Carlo Method , Occupational Exposure/analysis
5.
Eur J Cancer ; 49(13): 2841-50, 2013 Sep.
Article in English | MEDLINE | ID: mdl-23726267

ABSTRACT

BACKGROUND: Tivozanib is a potent and selective tyrosine kinase inhibitor of vascular endothelial growth factor receptors (VEGFR)-1, -2 and -3, with a long half-life. Tivozanib has demonstrated clinical activity and acceptable tolerability in renal cell carcinoma (RCC). This phase Ib study determined the recommended phase II dose (RP2D) and evaluated the safety and clinical activity of tivozanib plus temsirolimus, a mammalian target of rapamycin inhibitor. PATIENTS AND METHODS: Patients with advanced RCC were administered open-label tivozanib 0.5, 1.0 or 1.5mg/d orally (3 weeks on/1 week off) and temsirolimus 15 or 25 mg/week intravenously in a 3+3 dose-escalation design and subsequent expansion cohort. RESULTS: Of 27 patients treated, 20 patients had received ≥ 1 prior VEGF-targeted therapy. No dose-limiting toxicities occurred; the RP2D was determined to be tivozanib 1.5mg/d plus temsirolimus 25mg/week. Combination of tivozanib plus temsirolimus demonstrated acceptable tolerability and suggested no synergistic toxicity. The most common grade ≤ 3 adverse events were fatigue and thrombocytopenia (15% each). One patient each required dose reduction of tivozanib or temsirolimus due to an adverse event. Confirmed partial responses and stable disease were achieved at 23% and 68%, respectively. Pharmacokinetic analyses may suggest lack of an interaction between tivozanib and temsirolimus. CONCLUSIONS: In this small phase Ib study, tivozanib and temsirolimus were safely combined at the fully recommended dose and schedule of both agents. The observed clinical activity and manageable toxicity profile of this combination warrant further exploration in patients with RCC.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Renal Cell/drug therapy , Kidney Neoplasms/drug therapy , Administration, Intravenous , Administration, Oral , Adult , Aged , Angiogenesis Inhibitors/administration & dosage , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Antineoplastic Combined Chemotherapy Protocols/pharmacokinetics , Carcinoma, Renal Cell/enzymology , Carcinoma, Renal Cell/mortality , Drug Administration Schedule , Female , Humans , Kaplan-Meier Estimate , Kidney Neoplasms/enzymology , Kidney Neoplasms/mortality , Male , Maximum Tolerated Dose , Middle Aged , Phenylurea Compounds/administration & dosage , Protein Kinase Inhibitors/administration & dosage , Quinolines/administration & dosage , Sirolimus/administration & dosage , Sirolimus/analogs & derivatives , TOR Serine-Threonine Kinases/antagonists & inhibitors , TOR Serine-Threonine Kinases/metabolism , Time Factors , Treatment Outcome
6.
Rev. bras. plantas med ; Rev. bras. plantas med;14(2): 282-286, 2012. tab
Article in Portuguese | LILACS | ID: lil-650667

ABSTRACT

Este trabalho visou avaliar a bioatividade de extratos hidroalcoólicos de capim-limão sobre germinação e crescimento inicial da planta daninha picão-preto (Bidens pilosa L.) e da planta teste alface (Lactuca sativa L.). A partir de maceração hidroalcoólica de folhas secas e rasuradas (127,46 g) de capim-limão em 1L de álcool de cereais (70%), foram preparados os tratamentos como extratos hidroalcoólicos (HA) pela diluição (v/v) do macerado filtrado em água deionizada na proporção 1:1 (HA1:1) e 1:2 (HA1:2); dos quais foram obtidos os respectivos extratos secos (ES), a partir da evaporação da fase líquida de duas alíquotas de 50 mL de cada extrato HA, que após re-suspendidas em igual volume de água, sendo uma autoclavada (1 atm por 15 minutos), resultando nos extratos secos de HA1:1 e HA1:2 autoclavados (ES1:1A e ES1:2A) e nos extratos secos não autoclavados (ES1:1 e ES1:2); e água (AG) como controle. No primeiro dia dos bioensaios, foram aplicados 2 mL dos tratamentos, em DIC, com cinco repetições. Avaliou-se a porcentagem de germinação (G%), Índice de Velocidade de Germinação (IVG), altura da parte aérea (AA) e comprimento de radícula (CR) de aquênios (25) de picão-preto e de alface distribuídos em placas de Petri e mantidos em câmara de germinação (B.O.D.) por duas semanas. Os extratos HA1:1 e HA1:2 inibiram a G%, AA e CR das duas espécies. Todos os extratos secos reduziram a G%, IVG e o CR da alface. Para o picão preto, apenas o extrato ES1:1 reduziu a G% e o IVG foi reduzido por todos os extratos, a exceção do ES1:1A, mas nenhum extrato influenciou o crescimento inicial desta espécie.


This study aimed to evaluate the bioactivity of hydroalcoholic extract of lemongrass on the germination and early growth of the weed plant beggartick (Bidens pilosa L.) and the test plant lettuce (Lactuca sativa L.). From the hydroalcoholic maceration of dried and cut leaves of lemon grass (127.46 g) in 1 L grain alcohol (70%), the following treatments were prepared, hydro-alcoholic (HA) extracts by diluting (v/v) the macerate in deionized water at 1:1 (HA1:1) and 1:2 (HA1:2) proportions, obtaining the respective dried extracts (DE) from the evaporation of the liquid phase of two 50-mL aliquots of each HA extract; after resuspension in the same water volume, one aliquot was autoclaved (1 atm for 15 minutes) resulting in HA1:1 and HA1:2 dried autoclaved extracts (DE1:1A and DE1:2A) and in dried non-autoclaved extracts (ES1:1 and ES1:2), and water as control. On the first day of bioassays, 2mL of treatments were applied, in completely randomized design, with 5 replicates. Germination percentage (G%), Germination Speed Index (GSI), shoot height (SH) and radicle length (RL) of achenes (25) of beggartick and lettuce were evaluated after having been distributed in Petri dishes and kept in a germination chamber (B.O.D.) for two weeks. HA1:1 and HA1:2 extracts inhibited G%, SH and RL of both species. All dried extracts reduced G%, GSI and CR of lettuce. For beggartick, only ES1:1 extract reduced G% while GSI was reduced in all extracts, except ES1:1A, but no extract influenced the early growth of this species.


Subject(s)
Plants, Medicinal/classification , Plant Extracts/analysis , Germination , Plant Weeds/growth & development , Hydroalcoholic Solution , Cymbopogon/classification , Allelopathy
SELECTION OF CITATIONS
SEARCH DETAIL