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1.
Ann Oncol ; 35(6): 549-558, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38423389

RESUMO

BACKGROUND: 18F-fluoroestradiol (FES) positron emission tomography (PET)/computed tomography (CT) is considered an accurate diagnostic tool to determine whole-body endocrine responsiveness. In the endocrine therapy (ET)-FES trial, we evaluated 18F-FES PET/CT as a predictive tool in estrogen receptor-positive (ER+)/human epidermal growth factor receptor 2-negative (HER2-) metastatic breast cancer (MBC). PATIENTS AND METHODS: Eligible patients underwent an 18F-FES PET/CT at baseline. Patients with standardized uptake value (SUV) ≥ 2 received single-agent ET until progressive disease; patients with SUV < 2 were randomized to single-agent ET (arm A) or chemotherapy (ChT) (arm B). The primary objective was to compare the activity of first-line ET versus ChT in patients with 18F-FES SUV < 2. RESULTS: Overall, 147 patients were enrolled; 117 presented with 18F-FES SUV ≥ 2 and received ET; 30 patients with SUV < 2 were randomized to ET or ChT. After a median follow-up of 62.4 months, 104 patients (73.2%) had disease progression and 53 died (37.3%). Median progression-free survival (PFS) was 12.4 months [95% confidence interval (CI) 3.1-59.6 months] in patients with SUV < 2 randomized to arm A versus 23.0 months (95% CI 7.7-30.0 months) in arm B, [hazard (HR) = 0.71, 95% CI 0.3-1.7 months]; median PFS was 18.0 months (95% CI 11.2-23.1 months) in patients with SUV ≥ 2 treated with ET. Median overall survival (OS) was 28.2 months (95% CI 14.2 months-not estimable) in patients with SUV < 2 randomized to ET (arm A) versus 52.8 months (95% CI 16.2 months-not estimable) in arm B (ChT). Median OS was not reached in patients with SUV ≥ 2. 60-month OS rate was 41.6% (95% CI 10.4% to 71.1%) in arm A, 42.0% (95% CI 14.0% to 68.2%) in arm B, and 59.6% (95% CI 48.6% to 69.0%) in patients with SUV ≥ 2. In patients with SUV ≥ 2, 60-month OS rate was 72.6% if treated with aromatase inhibitors (AIs) versus 40.6% in case of fulvestrant or tamoxifen (P < 0.005). CONCLUSIONS: The ET-FES trial demonstrated that ER+/HER2- MBC patients are a heterogeneous population, with different levels of endocrine responsiveness based on 18F-FES CT/PET SUV.


Assuntos
Neoplasias da Mama , Estradiol , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Receptor ErbB-2 , Receptores de Estrogênio , Humanos , Feminino , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Neoplasias da Mama/metabolismo , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/mortalidade , Pessoa de Meia-Idade , Projetos Piloto , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Receptores de Estrogênio/metabolismo , Estradiol/análogos & derivados , Idoso , Receptor ErbB-2/metabolismo , Adulto , Antineoplásicos Hormonais/uso terapêutico , Compostos Radiofarmacêuticos , Prognóstico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico
2.
Nutr Res Rev ; 36(1): 98-119, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-34819193

RESUMO

Consumption of edible insects has been widely suggested as an environmentally sustainable substitute for meat to reduce greenhouse gas emissions. However, the novel research field for edible insects relies on the content of bioactive ingredients and on the ability to induce a functional effect in humans. The goal of this manuscript is to review the available body of evidence on the properties of edible insects in modulating oxidative and inflammatory stress, platelet aggregation, lipid and glucose metabolism and weight control. A search for literature investigating the functional role of edible insects was carried out in the PubMed database using specific keywords. A total of 55 studies, meeting inclusion criteria after screening, were divided on the basis of the experimental approach: in vitro studies, cellular models/ex vivo studies or in vivo studies. In the majority of the studies, insects demonstrated the ability to reduce oxidative stress, modulate antioxidant status, restore the impaired activity of antioxidant enzymes and reduce markers of oxidative damage. Edible insects displayed anti-inflammatory activity reducing cytokines and modulating specific transcription factors. Results from animal studies suggest that edible insects can modulate lipid and glucose metabolism. The limited number of studies focused on the assessment of anti-coagulation activity of edible insects makes it difficult to draw conclusions. More evidence from dietary intervention studies in humans is needed to support the promising evidence from in vitro and animal models about the functional role of edible insect consumption.


Assuntos
Insetos Comestíveis , Animais , Humanos , Antioxidantes/farmacologia , Inocuidade dos Alimentos , Glucose , Lipídeos
3.
Radiat Oncol ; 16(1): 57, 2021 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-33743759

RESUMO

OBJECTIVE: To analyze the pattern of failure in relation to pre-treatment [18F] FDG-PET/CT uptake in head and neck squamous cell carcinoma (HNSCC) patients treated with definitive radio-chemotherapy (RT-CHT). METHODS AND MATERIALS: From 2012 to 2016, 87 HNSCC patients treated with definitive RT-CHT, with intensity modulated radiation therapy with simultaneous integrated boost, underwent pre-treatment [18F] FDG-PET/CT (PETpre), and MRI/CT for radiotherapy (RT) planning purposes. Patients with local recurrence, received [18F] FDG-PET/CT, (PETrec) at the time of the discovery of recurrence. In these patients, the metabolic target volume (MTV), MTVpre and MTVrec were segmented on PET images by means of an adaptive thresholding algorithm. The overlapping volume between MTVpre and MTVrec (MTVpre&rec) was generated and the dose coverage of MTVrec and MTVpre&rec was checked on the planning CT using the D99 and D95 dose metrics. The recurrent volume was defined as: ''In-Field (IF)'', "Marginal recurrence" or ''Out-of-Field (OF)'' if D95 was respectively equal or higher than 95%, D95 was between 95 and 20% or the D95 was less than 20% of prescribed dose. RESULTS: We found 10/87 patients (11.5%) who had recurrence at primary site. Mean MTVpre was 12.2 cc (4.6-28.9 cc), while the mean MTVrec was 4.3 cc (1.1-12.7 cc). Two recurrences resulted 100% inside MTVpre, 4 recurrences were mostly inside (61-91%) and 4 recurrences were marginal to MTVpre (1-33%). At dosimetric analysis, five recurrences (50%) were IF, 4 (40%) marginal and one (10%) OF. The mean D99 of the overlapping volumes MTVpre&rec was 68.1 Gy (66.5-69.2 Gy), considering a prescription dose of 70 Gy to the planning target volume (PTV). CONCLUSION: Our study shows that the recurrence may originate from the volume with the highest FDG-signal. Tumor relapse in the high-dose volume support the hypothesis that an intensification of the dose on these volumes could be further assessed to prevent local relapse.


Assuntos
Fluordesoxiglucose F18/uso terapêutico , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Recidiva Local de Neoplasia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Carcinoma de Células Escamosas de Cabeça e Pescoço/diagnóstico por imagem , Adulto , Idoso , Quimiorradioterapia , Feminino , Fluordesoxiglucose F18/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Radiometria , Compostos Radiofarmacêuticos/metabolismo , Compostos Radiofarmacêuticos/uso terapêutico , Dosagem Radioterapêutica , Planejamento da Radioterapia Assistida por Computador , Radioterapia de Intensidade Modulada , Estudos Retrospectivos , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/terapia
4.
Food Res Int ; 132: 109093, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32331695

RESUMO

The effect of heat and equivalent thermal effect ( [Formula: see text] ) on discolouration of Spirulina algae extracts in water, sucrose and trehalose solutions at different concentration was investigated and kinetics of phycocyanin degradation evaluated by spectrophotometric and circular dichroism. At constant temperature, colour loss increased at increasing time and decreased at increasing solute concentration. Circular dichroism confirmed relation between colour loss and protein structure destabilization, and the thermostabilising effect of saccharides with sucrose performing better than trehalose. Apparent constant rate values determined by the Weibullian probabilistic model describe the corresponding phycocyanin degradation kinetics; a linear correlation between the activation energy and aw of the solutions has been found. Origin of phycocyanin and system saccharide concentration resulted significant discriminant factors on the discolouration when [Formula: see text] was taken into account. Results may find application in product formulation and processing optimisation, thereby the use of Spirulina extracts as colouring foodstuff could be enhanced.


Assuntos
Carboidratos/química , Temperatura Alta , Ficocianina/química , Estabilidade Proteica , Água/química , Dicroísmo Circular , Corantes de Alimentos , Cinética , Soluções , Espectrofotometria , Spirulina/química , Sacarose/química , Temperatura , Trealose/química
6.
Phys Med ; 31(5): 468-75, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25979211

RESUMO

PURPOSE: Resolution modeling (RM) of PET systems has been introduced in iterative reconstruction algorithms for oncologic PET. The RM recovers the loss of resolution and reduces the associated partial volume effect. While these methods improved the observer performance, particularly in the detection of small and faint lesions, their impact on quantification accuracy still requires thorough investigation. The aim of this study was to characterize the performances of the RM algorithms under controlled conditions simulating a typical (18)F-FDG oncologic study, using an anthropomorphic phantom and selected physical figures of merit, used for image quantification. METHODS: Measurements were performed on Biograph HiREZ (B_HiREZ) and Discovery 710 (D_710) PET/CT scanners and reconstructions were performed using the standard iterative reconstructions and the RM algorithms associated to each scanner: TrueX and SharpIR, respectively. RESULTS: RM determined a significant improvement in contrast recovery for small targets (≤17 mm diameter) only for the D_710 scanner. The maximum standardized uptake value (SUVmax) increased when RM was applied using both scanners. The SUVmax of small targets was on average lower with the B_HiREZ than with the D_710. Sharp IR improved the accuracy of SUVmax determination, whilst TrueX showed an overestimation of SUVmax for sphere dimensions greater than 22 mm. The goodness of fit of adaptive threshold algorithms worsened significantly when RM algorithms were employed for both scanners. CONCLUSIONS: Differences in general quantitative performance were observed for the PET scanners analyzed. Segmentation of PET images using adaptive threshold algorithms should not be undertaken in conjunction with RM reconstructions.


Assuntos
Algoritmos , Processamento de Imagem Assistida por Computador/métodos , Modelos Teóricos , Tomografia por Emissão de Pósitrons , Imagens de Fantasmas
7.
J Appl Microbiol ; 119(2): 487-99, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25989039

RESUMO

AIMS: To evaluate the antifungal activity of the volatile organic compounds (VOCs) produced by 75 different food-borne Bacillus species against Aspergillus niger, Aspergillus flavus, Aspergillus parasiticus, Aspergillus clavatus, Fusarium oxysporum f. sp. lactucae and Moniliophthora perniciosa and to determine the VOCs responsible for the inhibition. METHODS AND RESULTS: Bacillus strains inhibited fungal growth, although with different inhibition grades, with Bacillus subtilis, Bacillus amyloliquefaciens and Bacillus cereus strains as the best antifungal VOCs producers. While M. perniciosa DM4B and F. oxysporum f.sp. lactucae MA28 were the most sensitive fungi, A. parasiticus MG51 showed the greatest resistance to Bacillus VOCs exposure. Thirty-seven compounds were detected by SPME-GC-MS analysis, although similar patterns in volatile compounds were evidenced within the species, interspecific VOCs differences determined different effects on fungal growth. Multiple partial least regression (MPLRS) and antifungal activity of the individual VOCs revealed that only propanone, 1-butanol, 3-methyl-1-butanol, acetic acid, 2-methylpropanoic acid, carbon disulphide, 3-methylbutanoic acid and ethyl acetate were responsible for mycelia inhibition of M. perniciosa DM4B and F. oxysporum f.sp. lactucae MA28. CONCLUSIONS: The antagonistic activity of the Bacillus VOCs was demonstrated, although it cannot easily be explained through the action of a single molecule, thus a holistic approach could be more appropriate to estimate the fungal growth inhibition. SIGNIFICANCE AND IMPACT OF THE STUDY: VOCs produced by Bacillus from cooked food can be considered as promising antifungal compounds useful in the control of fungal plant pathogens. This study investigates for the first time the correlation between mycelia inhibition of M. perniciosa and F. oxysporum f. sp. lactucae and the VOCs emitted by the Bacillus species.


Assuntos
Antifúngicos/farmacologia , Bacillus/metabolismo , Fusarium/efeitos dos fármacos , Compostos Orgânicos Voláteis/farmacologia , Antifúngicos/metabolismo , Aspergillus niger/efeitos dos fármacos , Aspergillus niger/crescimento & desenvolvimento , Bacillus/química , Bacillus/classificação , Bacillus/genética , Fusarium/crescimento & desenvolvimento , Micélio/efeitos dos fármacos , Micélio/crescimento & desenvolvimento , Compostos Orgânicos Voláteis/metabolismo
8.
Neuroscience ; 302: 23-35, 2015 08 27.
Artigo em Inglês | MEDLINE | ID: mdl-25907448

RESUMO

Peroxisome proliferator-activated receptor (PPAR)γ is a potential pharmacological target for disease-modification in Parkinson's disease (PD), mainly acting by modulating the neuroinflammatory response. However, currently available agonists thiazolidinediones (TZDs) present limitations due to safety concerns. We evaluated a novel thiobarbituric-like compound MDG548, which acts as a functional PPARγ agonist displaying higher and selective binding affinity as compared to TZDs. Neuroprotection by MDG548 was tested in vitro and in a mouse MPTP model of PD, and neuroinflammation was investigated as a putative underlying mechanism. Viability assay on rat cortical neurons showed lack of cytotoxic effect in the dose-range of 100 nM-10 µM, which was therefore used for testing in vitro protection against H2O2 and MPP+ neurotoxicity. MDG548 dose-dependently increased cell viability of rat cortical neurons co-treated with H2O2 or pre-exposed to MDG548 prior to H2O2. Moreover, MDG548 induced neuroprotection in MPP+-treated PC12 cells. NF-kB activation was investigated to assess anti-inflammatory activity. MDG548 dose-dependently decreased NF-kB activation induced by LPS (100 ng/100ml) in HEK-Blue-hTLR4 cells. Given the supposed cancer risk of other PPARγ agonists, Ames test for genotoxicity was performed in Salmonella typhimurium TA100 and TA98 strains, showing that MDG548 was not genotoxic. In vivo, BL/6J mice were treated with MPTP (20mg/kg i.p. once/day for 4 days) in association with saline or MDG548 (2, 5, 10 mg/kg i.p.). Stereological counting showed that MDG548 prevented the MPTP-induced reduction in TH-positive cells in the substantia nigra compacta (SNc) at all doses tested. Moreover, MDG548 reduced reactive microglia and iNOS induction in the SNc. MDG548, being a non-TZD compound with high PPARγ affinity, void of genotoxicity, and with in vitro as well as in vivo neuroprotective properties, provides a promising alternative in the search for safer PPARγ agonists to be tested as potential disease-modifying drugs in PD.


Assuntos
1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina/farmacologia , Encefalite/tratamento farmacológico , Fármacos Neuroprotetores/uso terapêutico , Neurotoxinas/farmacologia , Tiobarbitúricos/uso terapêutico , Animais , Animais Recém-Nascidos , Células Cultivadas , Córtex Cerebral/citologia , Modelos Animais de Doenças , Encefalite/etiologia , Humanos , Peróxido de Hidrogênio/efeitos adversos , Hipoglicemiantes/farmacologia , Lipopolissacarídeos/farmacologia , Masculino , Camundongos Endogâmicos C57BL , NF-kappa B/metabolismo , Neurônios/efeitos dos fármacos , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/complicações , Transtornos Parkinsonianos/patologia , Ratos , Ratos Wistar , Rosiglitazona , Tiazolidinedionas/farmacologia , Tirosina 3-Mono-Oxigenase/metabolismo
9.
Leukemia ; 29(6): 1360-5, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25650091

RESUMO

In order to evaluate the predictive value of positron emission tomography-computed tomography (PET/CT) in discriminating the presence of a Richter's syndrome (RS) or a second malignancy (SM), as well as to evaluate its prognostic value in patients with chronic lymphocytic leukemia (CLL), we retrospectively analyzed the data of 90 patients who, in the suspicion of a RS or a SM, underwent PET/CT followed by the biopsy of the involved tissue. The median maximum Standardized Uptake Value (SUV max) in the presence of a CLL/small lymphocytic lymphoma, a diffuse large B-cell lymphoma (DLBCL), a Hodgkin lymphoma (HL), a SM were 3.5, 14.6, 7.0 and 6.3, respectively (P ⩽ 0.0001). A SUV max cutoff value ⩾ 5 showed a sensitivity, specificity, positive and negative predictive values of 88.2, 71.2, 51.3 and 94%, respectively, for the presence of a more aggressive disease (DLBCL, HL and SM). A SUV max ⩾ 5 identified also a subset of treatment naive patients with an inferior progression-free survival (P = 0.011) and overall survival (P = 0.067). These findings suggest that PET/CT may helpfully integrate the biologically-based prognostic stratification of CLL. Prospective clinical trials including larger cohorts of patients are needed to conclusively define the role and prognostic impact of PET/CT in the routine management of CLL patients.


Assuntos
Doença de Hodgkin/diagnóstico , Leucemia Linfocítica Crônica de Células B/diagnóstico , Linfoma Difuso de Grandes Células B/diagnóstico , Segunda Neoplasia Primária/diagnóstico , Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Terapia Combinada , Feminino , Seguimentos , Doença de Hodgkin/mortalidade , Doença de Hodgkin/terapia , Humanos , Leucemia Linfocítica Crônica de Células B/mortalidade , Leucemia Linfocítica Crônica de Células B/terapia , Linfoma Difuso de Grandes Células B/mortalidade , Linfoma Difuso de Grandes Células B/terapia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Segunda Neoplasia Primária/mortalidade , Segunda Neoplasia Primária/terapia , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida
10.
Food Chem ; 174: 256-62, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25529678

RESUMO

The effect of roasting on the content of flavanols and proanthocyanidins and on the antioxidant activity of cocoa beans was investigated. Cocoa beans were roasted at three temperatures (125, 135 and 145 °C), for different times, to reach moisture contents of about 2 g 100 g(-1). Flavanols and proanthocyanidins were determined, and the antioxidant activity was tested by total phenolic index (TPI), ferric reducing antioxidant power (FRAP) and total radical trapping antioxidant parameter (TRAP) methods. The rates of flavanol and total proanthocyanidin loss increased with roasting temperatures. Moisture content of the roasted beans being equal, high temperature-short time processes minimised proanthocyanidins loss. Moisture content being equal, the average roasting temperature (135 °C) determined the highest TPI and FRAP values and the highest temperature (145 °C) determined the lowest TPI values. Moisture content being equal, low temperature-long time roasting processes maximised the chain-breaking activity, as determined by the TRAP method.


Assuntos
Antioxidantes/farmacologia , Cacau/química , Flavonóis/análise , Proantocianidinas/análise , Manipulação de Alimentos , Fenóis/análise , Temperatura
11.
Phys Med ; 30(7): 822-6, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24704002

RESUMO

The aim of this study was to determine the suspension level for the sensitivity of an intraoperative scintillation gamma probe in the detection of the sentinel lymph node (SLN) in melanoma patients. Thirty-eight consecutive patients with melanoma were enrolled in the study during a 12-month period and underwent lymphatic scintigraphy after the peritumoral intradermal administration of about 14 MBq of (99m)Tc-nanocolloids. The SLNs were successfully removed during the surgical intervention about 4 h later. To identify and localize the SLN, a scintillation NaI(Tl) collimated probe was used. Predictably, the probe sensitivity decreased as the photopeak energy window was progressively narrowed, from 6.9 ± 0.7 counts per second (cps)/kBq (designated as the 'optimum,' or 'OPT,' sensitivity) to 2.5 ± 0.3 cps/kBq (LOW sensitivity) and to 1.4 ± 0.2 cps/kBq (VLOW sensitivity). Maximum lymph node count rates (cps) were determined for the foregoing energy windows prior to skin incision (PREOPT, PRELOW, PREVLOW, respectively) and in vivo after incision (INVOPT, INVLOW, INVVLOW). Forty-three SLNs were removed with a mean source-to-detector distance of 46 ± 24 mm (min 12 mm, max 92 mm). Four SLNs could not have been detected using PRELOW. This figure would have decreased to 34, with nine undetectable lymph nodes, with PREVLOW. One SLN could not have been identified using INVLOW and four could not have be identified using INVVLOW. In the clinical scenario of SLN detection in melanoma patients, a system sensitivity of 2.5 cps/kBq represents a suspension level, that is, a level under which the equipment must be suspended from clinical use and the poor performance must be investigated.


Assuntos
Melanoma/diagnóstico por imagem , Melanoma/patologia , Contagem de Cintilação/instrumentação , Adulto , Idoso , Feminino , Humanos , Período Intraoperatório , Metástase Linfática , Masculino , Melanoma/cirurgia , Pessoa de Meia-Idade , Cintilografia , Sensibilidade e Especificidade
12.
J Ethnopharmacol ; 147(1): 84-91, 2013 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-23500881

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: The decoction of the roots of Hemidesmus indicus is widely used in the Indian traditional medicine for the treatment of blood diseases, dyspepsia, loss of taste, dyspnea, cough, poison, menorrhagia, fever, and diarrhea. Poly-herbal preparations containing Hemidesmus are often used by traditional medical practitioners for the treatment of cancer. The aim of this study was to investigate the cytodifferentiative, cytostatic and cytotoxic potential of a decoction of Hemidesmus indicus's roots (0.31-3 mg/mL) on a human promyelocytic leukemia cell line (HL-60). MATERIALS AND METHODS: The decoction of Hemidesmus indicus was characterized by HPLC to quantify its main phytomarkers. Induction of apoptosis, cell-cycle analysis, levels of specific membrane differentiation markers were evaluated by flow cytometry. The analysis of cell differentiation by nitroblue tetrazolium (NBT) reducing activity, adherence to the plastic substrate, α-napthyl acetate esterase activity and morphological analysis was performed through light microscopy (LM) and transmission electron microscopy (TEM). RESULTS: Starting from the concentration of 0.31 mg/ml, Hemidesmus indicus induced cytotoxicity and altered cell-cycle progression, through a block in the G0/G1 phase. The decoction caused differentiation of HL-60 cells as shown by NBT reducing activity, adherence to the plastic substrate, α-naphtyl acetate esterase activity, and increasing expression of CD14 and CD15. The morphological analysis by LM and TEM clearly showed the presence of granulocytes and macrophages after Hemidesmus indicus treatment. CONCLUSIONS: The cytodifferentiating, cytotoxic and cytostatic activities of Hemidesmus indicus offers a scientific basis for its use in traditional medicine. Its potent antileukemic activity provides a pre-clinical evidence for its traditional use in anticancer pharmacology. Further experiments are worthwhile to determine the in vivo anticancer potential of this plant decoction and its components.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Hemidesmus , Leucemia Promielocítica Aguda/patologia , Preparações de Plantas/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Adesão Celular/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Citometria de Fluxo , Fucosiltransferases/metabolismo , Granulócitos/efeitos dos fármacos , Granulócitos/imunologia , Células HL-60 , Hemidesmus/química , Humanos , Leucemia Promielocítica Aguda/imunologia , Antígenos CD15/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Microscopia Eletrônica de Transmissão , Fitoterapia , Preparações de Plantas/química , Preparações de Plantas/isolamento & purificação , Raízes de Plantas , Plantas Medicinais , Fatores de Tempo
13.
Phys Med ; 28(3): 210-20, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21784686

RESUMO

PET scanners require routine monitoring and quality control (QC) to ensure proper scanner performance. QC helps to ensure that PET equipment performs as specified by the manufacturer and that there have not been significant changes in the system response since acceptance. In this work we describe the maintenance history and we report on the results obtained from the PET system QC testing program over 5 years at two centers, both utilizing a Siemens Biograph 16 HiRez PET/CT system. QC testing programs were based on international standards and included the manufacturer's daily QC, monthly uniformity and sensitivity, quarterly cross-calibration and annual resolution and image quality. For the Winnipeg and Novara sites, two and one PET detector blocks have been replaced, respectively. Neither system has had other significant PET system related hardware replacements. The manufacturer's suggested daily QC was sensitive to detecting problems in the function of PET detector elements. The same test was not sensitive for detecting long term drifts in the systems: the Novara system observed a significant deterioration over five years of testing in the sensitivity which exhibited a decrease of 16% as compared to its initial value measured at system installation. The measure of the energy spectrum, showed that the 511 keV photopeak had shifted to a position of 468 keV. This shift was corrected by having service personnel perform a complete system calibration and detector block setup. We recommend including tests of system energy response and of sensitivity as part of a QC program since they can provide useful information on the actual performance of the scanner. A modification of the daily QC test by the manufacturer is suggested to monitor the long term stability of the system. Image quality and spatial resolution tests have proven to be of limited value for monitoring the system over time.


Assuntos
Imageamento Tridimensional/instrumentação , Imageamento Tridimensional/normas , Tomografia por Emissão de Pósitrons/instrumentação , Tomografia por Emissão de Pósitrons/normas , Irradiação Corporal Total/instrumentação , Irradiação Corporal Total/normas , Calibragem , Documentação , Agências Internacionais/normas , Controle de Qualidade , Contagem de Cintilação , Sensibilidade e Especificidade
14.
Neuroscience ; 176: 336-48, 2011 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-21193020

RESUMO

The hypothesis that attention deficits induced by the hypofunction of N-methyl d-aspartate (NMDA) receptors in the prefrontal cortex (PFC) might be associated with increased glutamate release and changes in the phosphorylation of the cyclic adenosine monophosphate response element-binding protein on serine 133 (p-S(133)CREB) was investigated in this study. Infusion of 50 ng/side 3-(R)-2-carboxypiperazin-4-propyl-1-phosphonic acid ((R)-CPP), a competitive glutamate NMDA receptor antagonist, into the medial prefrontal cortex (mPFC) of rats performing the five-choice serial reaction time (5-CSRT) task, reduced accuracy of visual discrimination (measured by % correct responses) and enhanced impulsivity (measured by the number of premature responses) and compulsivity (measured by the number of perseverative responses). The mGluR2/3 receptor agonist, LY379268, injected s.c. at 0.1 mg/kg, reduced (R)-CPP-induced impairment in attentional functioning (accuracy) and impulsivity but not compulsive perseveration. In parallel studies using microdialysis technique and Western blot analysis we found that (R)-CPP (100 µM) infused in the medial prefrontal cortex increased glutamate efflux whereas injected in the medial prefrontal cortex at a dose causing impairments in attentional performance (50 ng/side) increased p-S(133)CREB in the frontal cortex (FC), decreased it in the caudate-putamen (CPu) and was without effect in the nucleus accumbens (NAC). LY379268 at the dose effective in reducing (R)-CPP-induced behavioral deficit reduced both the (R)-CPP-induced rise in glutamate efflux in the prefrontal cortex and the increase in p-S(133)CREB in the frontal cortex but was without effect on the decrease in p-S(133)CREB in the caudate-putamen. The data provide evidence that enhanced glutamate release and phosphorylation of cAMP response element binding protein (CREB) on serine 133 may be associated to attention deficit and loss of impulse control. Furthermore they suggest that mGluR2/3 agonists have a therapeutic potential for cognitive deficits.


Assuntos
Comportamento Animal/fisiologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Ácido Glutâmico/metabolismo , Córtex Pré-Frontal/metabolismo , Receptores de Glutamato Metabotrópico/metabolismo , Aminoácidos/farmacologia , Animais , Transtorno do Deficit de Atenção com Hiperatividade/metabolismo , Comportamento Animal/efeitos dos fármacos , Western Blotting , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Imuno-Histoquímica , Masculino , Microdiálise , Microinjeções , Fosforilação , Piperazinas/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Ratos , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores
15.
Phys Med Biol ; 54(19): 5861-72, 2009 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-19759405

RESUMO

The purpose of this study was to quantify the influence of outside field of view (FOV) activity concentration (A(c)(,out)) on the noise equivalent count rate (NECR), scatter fraction (SF) and image quality of a 3D LSO whole-body PET/CT scanner. The contrast-to-noise ratio (CNR) was the figure of merit used to characterize the image quality of PET scans. A modified International Electrotechnical Commission (IEC) phantom was used to obtain SF and counting rates similar to those found in average patients. A scatter phantom was positioned at the end of the modified IEC phantom to simulate an activity that extends beyond the scanner. The modified IEC phantom was filled with (18)F (11 kBq mL(-1)) and the spherical targets, with internal diameter (ID) ranging from 10 to 37 mm, had a target-to-background ratio of 10. PET images were acquired with background activity concentrations into the FOV (A(c)(,bkg)) about 11, 9.2, 6.6, 5.2 and 3.5 kBq mL(-1). The emission scan duration (ESD) was set to 1, 2, 3 and 4 min. The tube inside the scatter phantom was filled with activities to provide A(c)(,out) in the whole scatter phantom of zero, half, unity, twofold and fourfold the one of the modified IEC phantom. Plots of CNR versus the various parameters are provided. Multiple linear regression was employed to study the effects of A(c)(,out) on CNR, adjusted for the presence of variables (sphere ID, A(c)(,bkg) and ESD) related to CNR. The presence of outside FOV activity at the same concentration as the one inside the FOV reduces peak NECR of 30%. The increase in SF is marginal (1.2%). CNR diminishes significantly with increasing outside FOV activity, in the range explored. ESD and A(c)(,out) have a similar weight in accounting for CNR variance. Thus, an experimental law that adjusts the scan duration to the outside FOV activity can be devised. Recovery of CNR loss due to an elevated A(c)(,out) activity seems feasible by modulating the ESD in individual bed positions according to A(c)(,out).


Assuntos
Lutécio , Tomografia por Emissão de Pósitrons/instrumentação , Silicatos , Tomografia Computadorizada por Raios X/instrumentação , Imagem Corporal Total/instrumentação , Artefatos , Humanos , Imageamento Tridimensional , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/métodos , Tomografia por Emissão de Pósitrons/normas , Tomografia Computadorizada por Raios X/métodos , Tomografia Computadorizada por Raios X/normas , Imagem Corporal Total/métodos
16.
Radiol Med ; 114(1): 1-17, 2009 Feb.
Artigo em Inglês, Italiano | MEDLINE | ID: mdl-19082787

RESUMO

PURPOSE: The aim of this pilot study was to compare positron emission tomography computed tomography (PET-CT) and whole-body DWIBS in staging oncological patients to determine the staging accuracy of whole-body DWIBS. MATERIALS AND METHODS: We initiated a prospective, blinded investigation on 29 patients affected by oncological diseases (n=14) or lymphoma (n=15), who underwent fluorodeoxyglucose (FDG)-based PET-CT and whole-body DWIBS for restaging purposes. Magnetic resonance (MR) imaging was conducted with a multistack (n=4) DWIBS pulse sequence. Images were read independently by two experienced radiologists and one nuclear physician. Statistical analysis assessed interobserver agreement and diagnostic accuracy. RESULTS: Whole-body DWIBS had a room occupation time of 20 min. Mean postprocessing time was 15 min (range 10-17 min). Mean reading time was 20 min for reader 1 (range 15-25 min) and 18 min for reader 2 (range 13-22 min). Interobserver agreement was almost perfect (=0.93). Reader 1 had a sensitivity of 89.07%, a specificity of 98.5%, and an accuracy of 97.65%, with a positive predictive value (PPV) of 85.48% and a negative predictive value (NPV) of 98.91%. Reader 2 had a sensitivity of 87.39%, a specificity of 98.39% and a diagnostic accuracy of 97.8%, with a PPV of 88.13% and a NPV of 98.75%. CONCLUSIONS: The whole-body DWIBS protocol provided a fast whole-body examination with high specificity and NPV. One major bias of the study was the inclusion of patients with diffuse disease and advanced disease stage and the heterogeneity of the neoplastic diseases included.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neoplasias/diagnóstico , Tomografia por Emissão de Pósitrons , Tomografia Computadorizada por Raios X , Imagem Corporal Total/métodos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Algoritmos , Interpretação Estatística de Dados , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias/diagnóstico por imagem , Neoplasias/patologia , Variações Dependentes do Observador , Projetos Piloto , Software
17.
Med Phys ; 34(10): 3854-65, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17985631

RESUMO

The aim of our work is to describe the way in which physical figures of merit such as contrast-to-noise ratio (CNR) behave when varying acquisition parameters such as emission scan duration (ESD) or activity at the start of acquisition (A(acq)) that in clinical practice can be selected by the user, or object properties such as target dimensions or target-to-background (T/B) ratio, which depend uniquely on the intrinsic characteristics of the object being imaged. Figures of merit, used to characterize image quality and quantitative accuracy for a 3D-LSO based PET/CT scanner, were studied as a function of ESD and A(acq) for different target sizes and T/B ratios using a multivariate approach in a wide range of conditions approaching the ones that can be encountered in clinical practice. An annular ring of water bags of 3 cm thickness was fitted over an IEC phantom in order to obtain counting rates similar to those found in average patients. The average scatter fraction (SF) of the modified IEC phantom was similar to the mean SF measured on patients with a similar scanner. A supplemental set of micro-hollow spheres was positioned inside the phantom. The NEMA NU 2-2001 scatter phantom was positioned at the end of the IEC phantom to approximate the clinical situation of having activity that extends beyond the scanner. The phantoms were filled with a solution of water and 18F (12 kBq/mL) and the spheres with various T/B ratios of 22.5, 10.3, and 3.6. Sequential imaging was performed to acquire PET images with varying background activity concentrations of about 12, 9, 6.4, 5.3, and 3.1 kBq/mL, positioned on the linear portion of the phantom's NECR curve, well below peak NECR of 61.2 kcps that is reached at 31.8 kBq/mL. The ESD was set to 1, 2, 3, and 4 min/bed. With T/B ratios of 3.6, 10.3, and 22.5, the 13.0, 8.1, and 6.5 mm spheres were detectable for the whole ranges of background activity concentration and ESD, respectively. The ESD resulted as the most significant predictor of CNR variance, followed by T/B ratio and the cross sectional area of the given sphere. Only last comes A(acq) with a weight more than halved with respect to ESD. Thus, raising ESD seems to be much more effective than raising A(acq) in order to obtain higher CNR, which is the physical figure of merit closely related with target detectability, at least in the simple task of the signal known exactly background known exactly model.


Assuntos
Tomografia por Emissão de Pósitrons/métodos , Tomografia Computadorizada por Raios X/métodos , Imagem Corporal Total/métodos , Algoritmos , Humanos , Processamento de Imagem Assistida por Computador , Imageamento Tridimensional , Modelos Estatísticos , Imagens de Fantasmas , Tomografia por Emissão de Pósitrons/instrumentação , Análise de Regressão , Software , Técnica de Subtração , Tomografia Computadorizada por Raios X/instrumentação , Imagem Corporal Total/instrumentação
18.
Nat Prod Res ; 21(2): 167-79, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17365705

RESUMO

Methanolic extracts of Myrtus communis leaves from two Italian regions (Calabria and Sardinia) were processed to determine the content of myrtenol, linalool and eucalyptol. Among the Calabrian and Sardinian myrtle samples, linalool and eucalyptol chemotypes were prevalent. The extracts were also tested for antioxidant, antibacterial and antifungal activities. Myrtle leaves samples were dried and extracted through maceration. Partition chromatography was adopted to separate myrtenol, linalool and eucalyptol fractions. Analyses were performed through GC and GC-MS. Some of the samples showed a good scavenger activity evidenced by DPPH radical scavenging assay and beta-carotene bleaching test. Antibacterial and antifungal activities were generally weak. The phytochemical and biological characterization of all the extracts were determined with an aim to characterize the intra-specific biodiversity of myrtle populations.


Assuntos
Biodiversidade , Metanol/química , Myrtus/química , Extratos Vegetais/química , Monoterpenos Acíclicos , Antibacterianos/química , Antibacterianos/farmacologia , Antifúngicos/química , Antifúngicos/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Bactérias/efeitos dos fármacos , Compostos de Bifenilo/química , Cromatografia Gasosa , Cicloexanóis/química , Cicloexanóis/farmacologia , Eucaliptol , Fungos/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Geografia , Hidrazinas/química , Itália , Monoterpenos/química , Monoterpenos/farmacologia , Myrtus/crescimento & desenvolvimento , Oxirredução/efeitos dos fármacos , Picratos , Extratos Vegetais/farmacologia , Folhas de Planta/química
19.
Nat Prod Res ; 19(4): 379-87, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15938146

RESUMO

The biovariability of Helichrysum italicum (Roth) Don grown wild in Calabria and Sardinia (Italy) was reported. This species has been characterized through the detection, isolation and quantitative evaluation of chemical markers (alpha-terpinolene, trans-cariophyllene and neryl acetate) by GC and GC-MS. Antioxidant activity of the methanolic H. italicum extracts using DPPH and beta-carotene bleaching test showed that the Calabrian samples were more active than those from Sardinia. The antibacterial activity of all extracts evidenced the best performance on the Gram positive bacteria particularly on Micrococcus luteus. Moreover, antifungal activity of all extracts was also tested evidencing important results particularly on the phytopathogene fungus Pythium ultimum. In general, as regards the antifungal activity, the extracts from Sardinia were more active than those from Calabria. The phytochemical analysis and the biological activity data suggested a possible use of these plant matrices in alimentary, cosmetic and pharmaceutical fields.


Assuntos
Helichrysum/química , Óleos Voláteis/química , Antibacterianos/farmacologia , Antifúngicos/farmacologia , Antioxidantes/farmacologia , Meio Ambiente , Helichrysum/fisiologia , Itália , Óleos Voláteis/metabolismo , Extratos Vegetais/farmacologia
20.
Phytother Res ; 19(2): 152-7, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15852493

RESUMO

Certain jaesekanadiol p-hydroxy- and p-methoxybenzoates - typical of Ferula communis and Ferula arrigonii sardinian plants - show antiproliferative activity on human colon cancer less. The inhibitory doses 50%, calculated after 72 h of treatment, revealed that the antiproliferative capacity of the compounds was in the following descending order: ferutinin > 2alpha-OH-ferutidin > ferutidin > siol anisate > lapiferin > jaeskeanadiol. Evidence is presented that interaction with type II estrogen-binding sites (EBS) underlies this activity.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Ferula , Fitoterapia , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/uso terapêutico , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Neoplasias do Colo/tratamento farmacológico , Neoplasias do Colo/patologia , Humanos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/uso terapêutico
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