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1.
EFSA J ; 21(11): e08353, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37965303

RESUMO

Following a request from the European Commission (EC), the EFSA Panel on Nutrition, Novel Foods and Food Allergens (NDA) was asked to deliver a scientific opinion on the revision of the tolerable upper intake level (UL) for folic acid/folate. Systematic reviews of the literature were conducted to assess evidence on priority adverse health effects of excess intake of folate (including folic acid and the other authorised forms, (6S)-5-methyltetrahydrofolic acid glucosamine and l-5-methyltetrahydrofolic acid calcium salts), namely risk of cobalamin-dependent neuropathy, cognitive decline among people with low cobalamin status, and colorectal cancer and prostate cancer. The evidence is insufficient to conclude on a positive and causal relationship between the dietary intake of folate and impaired cognitive function, risk of colorectal and prostate cancer. The risk of progression of neurological symptoms in cobalamin-deficient patients is considered as the critical effect to establish an UL for folic acid. No new evidence has been published that could improve the characterisation of the dose-response between folic acid intake and resolution of megaloblastic anaemia in cobalamin-deficient individuals. The ULs for folic acid previously established by the Scientific Committee on Food are retained for all population groups, i.e. 1000 µg/day for adults, including pregnant and lactating women, 200 µg/day for children aged 1-3 years, 300 µg/day for 4-6 years, 400 µg/day for 7-10 years, 600 µg/day for 11-14 years and 800 µg/day for 15-17 years. A UL of 200 µg/day is established for infants aged 4-11 months. The ULs apply to the combined intake of folic acid, (6S)-5-methyltetrahydrofolic acid glucosamine and l-5-methyltetrahydrofolic acid calcium salts, under their authorised conditions of use. It is unlikely that the ULs for supplemental folate are exceeded in European populations, except for regular users of food supplements containing high doses of folic acid/5-methyl-tetrahydrofolic acid salts.

2.
EFSA J ; 18(3): e06032, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32874250

RESUMO

The Panel on Food Additives and Flavourings (FAF) provided a scientific opinion re-evaluating the safety of acetic acid, lactic acid, citric acid, tartaric acid, mono- and diacetyltartaric acids, mixed acetic and tartaric acid esters of mono- and diglycerides of fatty acids (E 472a-f) as food additives. All substances had been previously evaluated by the Scientific Committee for Food (SCF) and by the Joint FAO/WHO Expert Committee on Food Additives (JECFA). Hydrolysis of E472a,b,c,e was demonstrated in various experimental systems, although the available data on absorption, distribution, metabolism, excretion (ADME) were limited. The Panel assumed that E472a-f are extensively hydrolysed in the GI tract and/or (pre-)systemically after absorption into their individual hydrolysis products which are all normal dietary constituents and are metabolised or excreted intact. No adverse effects relevant for humans have been identified from the toxicological database available for E472a-f. The Panel considered that there is no need for a numerical acceptable daily intake (ADI) for E 472a,b,c. The Panel also considered that only l(+)-tartaric acid has to be used in the manufacturing process of E472d,e,f. The Panel established ADIs for E 472d,e,f based on the group ADI of 240 mg/kg body weight (bw) per day, expressed as tartaric acid, for l(+)-tartaric acid-tartrates (E334-337, 354) and considering the total amount of l(+)-tartaric acid in each food additive. Exposure estimates were calculated for all food additives individually, except for E 472e and f, using maximum level, refined exposure and food supplements consumers only scenarios. Considering the exposure estimates, there is no safety concern at their reported uses and use levels. In addition, exposure to tartaric acid released from the use of E 472d,e,f was calculated. The Panel also proposed a number of recommendations.

3.
Clin Cancer Res ; 26(21): 5682-5688, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32546648

RESUMO

PURPOSE: To assess the predictive value of molecular breast cancer subtypes in premenopausal patients with hormone receptor-positive early breast cancer who received adjuvant endocrine treatment or chemotherapy. EXPERIMENTAL DESIGN: Molecular breast cancer subtypes were centrally assessed on whole tumor sections by IHC in patients of the Austrian Breast and Colorectal Cancer Study Group Trial 5 who had received either 5 years of tamoxifen/3 years of goserelin or six cycles of cyclophosphamide, methotrexate, and fluorouracil (CMF). Luminal A disease was defined as Ki67 <20% and luminal B as Ki67 ≥20%. The luminal B/HER2-positive subtype displayed 3+ HER2-IHC or amplification by ISH. Recurrence-free survival (RFS) and overall survival (OS) were analyzed using Cox models adjusted for clinical and pathologic factors. RESULTS: 185 (38%), 244 (50%), and 59 (12%) of 488 tumors were classified as luminal A, luminal B/HER2-negative and luminal B/HER2-positive, respectively. Luminal B subtypes were associated with poor outcome. Patients with luminal B tumors had a significantly shorter RFS [adjusted HR for recurrence: 2.22; 95% confidence interval (CI), 1.41-3.49; P = 0.001] and OS (adjusted HR for death: 3.51; 95% CI, 1.80-6.87; P < 0.001). No interaction between molecular subtypes and treatment was observed (test for interaction: P = 0.84 for RFS; P = 0.69 for OS). CONCLUSIONS: Determination of molecular subtypes by IHC is an independent prognostic factor for recurrence and death in premenopausal women with early-stage, hormone receptor-positive breast cancer but is not predictive for outcome of adjuvant treatment with tamoxifen/goserelin or CMF.See related commentary by Hunter et al., p. 5543.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Antígeno Ki-67/genética , Recidiva Local de Neoplasia/tratamento farmacológico , Receptor ErbB-2/genética , Tamoxifeno/administração & dosagem , Adulto , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Neoplasias da Mama/classificação , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Quimioterapia Adjuvante/efeitos adversos , Ciclofosfamida/administração & dosagem , Ciclofosfamida/efeitos adversos , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Fluoruracila/efeitos adversos , Gosserrelina/administração & dosagem , Gosserrelina/efeitos adversos , Humanos , Metotrexato/administração & dosagem , Metotrexato/efeitos adversos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/classificação , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/patologia , Pré-Menopausa/efeitos dos fármacos , Pré-Menopausa/genética , Intervalo Livre de Progressão , Receptores de Estrogênio/genética , Receptores de Progesterona/genética , Tamoxifeno/efeitos adversos
4.
Food Chem Toxicol ; 111: 114-124, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-29129665

RESUMO

Mechanisms how colorectal cancer (CRC) cells penetrate blood micro-vessel endothelia and metastasise is poorly understood. To study blood endothelial cell (BEC) barrier breaching by CRC emboli, an in vitro assay measuring BEC-free areas underneath SW620 cell spheroids, so called "circular chemorepellent induced defects" (CCIDs, appearing in consequence of endothelial retraction), was adapted and supported by Western blotting, EIA-, EROD- and luciferase reporter assays. Inhibition of ALOX12 or NF-κB in SW620 cells or BECs, respectively, caused attenuation of CCIDs. The FDA approved drugs vinpocetine [inhibiting ALOX12-dependent 12(S)-HETE synthesis], ketotifen [inhibiting NF-κB], carbamazepine and fenofibrate [inhibiting 12(S)-HETE and NF-κB] significantly attenuated CCID formation at low µM concentrations. In the 5-FU-resistant SW620-R/BEC model guanfacine, nifedipine and proadifen inhibited CCIDs stronger than in the naïve SW620/BEC model. This indicated that in SW620-R cells formerly silent (yet unidentified) genes became expressed and targetable by these drugs in course of resistance acquisition. Fenofibrate, and the flavonoids hispidulin and apigenin, which are present in medicinal plants, spices, herbs and fruits, attenuated CCID formation in both, naïve- and resistant models. As FDA-approved drugs and food-flavonoids inhibited established and acquired intravasative pathways and attenuated BEC barrier-breaching in vitro, this warrants testing of these compounds in CRC models in vivo.


Assuntos
Neoplasias Colorretais/patologia , Células Endoteliais/fisiologia , Endotélio Vascular/fisiologia , Flavonoides/farmacologia , Esferoides Celulares/fisiologia , Araquidonato 12-Lipoxigenase/genética , Araquidonato 12-Lipoxigenase/metabolismo , Bloqueadores dos Canais de Cálcio/farmacologia , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica , Humanos , NF-kappa B/genética , NF-kappa B/metabolismo , Metástase Neoplásica/fisiopatologia , Preparações Farmacêuticas
5.
Clin Breast Cancer ; 15(6): 505-11, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26195436

RESUMO

BACKGROUND: Neoadjuvant chemotherapy (NACT) is an accepted treatment approach in early-stage breast cancer. In contrast, the potential role of postneoadjuvant chemotherapy after taxane-containing NACT remains unclear. The aim of this study was to evaluate postneoadjuvant chemotherapy and further prognostic factors that predict outcome in women without pathologic complete remission (pCR). PATIENTS AND METHODS: A total of 377 patients with breast cancer who received preoperative chemotherapy were included in this retrospective study. Patients without standard NACT (6 cycles of epirubicin with docetaxel) or primary metastatic breast cancer and locally advanced, inoperable cancer were excluded from further analysis (n = 186). This resulted in a study population of 191 women (30 [15.7%] with pCR; 161 [84.3%] without pCR). Major outcome parameters were event-free survival (EFS) and overall survival (OS). The following parameters were tested for their prognostic role: postneoadjuvant chemotherapy, patient age, breast cancer subtype (luminal/HER2-negative tumors, HER2-positive tumors, and triple-negative tumors), histological grade, pCR, residual lymph node invasion, and residual invasive tumor size. RESULTS: At a median follow-up of 54 months, 51 disease relapses (26.7%) and 21 deaths (11%) were observed. In a comparison of patients with pCR with those without, no significant differences in EFS or OS were observed. Postneoadjuvant chemotherapy was significantly associated with shorter OS in patients without pCR. CONCLUSION: In this population, which included a high percentage of patients with luminal cancers, pCR did not predict for improved OS. Postneoadjuvant chemotherapy showed no discernible benefit even in subgroups with aggressive tumor biology or significant remaining tumor burden. The use of such treatment should therefore be discouraged outside of clinical trials.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias da Mama/tratamento farmacológico , Quimioterapia Adjuvante/métodos , Neoplasia Residual/tratamento farmacológico , Adulto , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Cisplatino/administração & dosagem , Intervalo Livre de Doença , Feminino , Fluoruracila/administração & dosagem , Humanos , Estimativa de Kaplan-Meier , Metotrexato/administração & dosagem , Pessoa de Meia-Idade , Terapia Neoadjuvante , Neoplasia Residual/mortalidade , Neoplasia Residual/patologia , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos
6.
Phytomedicine ; 22(1): 213-22, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25636891

RESUMO

Epigallocatechin gallate (EGCG), ellagic acid (EA) and rosmarinic acid (RA) are natural polyphenols exerting cancer chemopreventive effects. Ribonucleotide reductase (RR; EC 1.17.4.1) converts ribonucleoside diphosphates into deoxyribonucleoside diphosphates being essential for DNA replication, which is why the enzyme is considered an excellent target for anticancer therapy. EGCG, EA, and RA dose-dependently inhibited the growth of human HL-60 promyelocytic leukemia cells, exerted strong free radical scavenging potential, and significantly imbalanced nuclear deoxyribonucleoside triphosphate (dNTP) concentrations without distinctly affecting the protein levels of RR subunits (R1, R2, p53R2). Incorporation of (14)C-cytidine into nascent DNA of tumor cells was also significantly lowered, being equivalent to an inhibition of DNA synthesis. Consequently, treatment with EGCG and RA attenuated cells in the G0/G1 phase of the cell cycle, finally resulting in a pronounced induction of apoptosis. Sequential combination of EA and RA with the first-line antileukemic agent arabinofuranosylcytosine (AraC) synergistically potentiated the antiproliferative effect of AraC, whereas EGCG plus AraC yielded additive effects. Taken together, we show for the first time that EGCG, EA, and RA perturbed dNTP levels and inhibited cell proliferation in human HL-60 promyelocytic leukemia cells, with EGCG and RA causing a pronounced induction of apoptosis. Due to these effects and synergism with AraC, these food ingredients deserve further preclinical and in vivo testing as inhibitors of leukemic cell proliferation.


Assuntos
Antineoplásicos/farmacologia , Catequina/análogos & derivados , Cinamatos/farmacologia , Citarabina/farmacologia , Depsídeos/farmacologia , Ácido Elágico/farmacologia , Trifosfato de Adenosina/química , Catequina/farmacologia , Proliferação de Células/efeitos dos fármacos , DNA/biossíntese , Sinergismo Farmacológico , Sequestradores de Radicais Livres/farmacologia , Células HL-60/efeitos dos fármacos , Humanos , Estrutura Molecular , Inibidores da Síntese de Ácido Nucleico/farmacologia , Nucleotídeos de Timina/química , Ácido Rosmarínico
7.
Cancer Lett ; 250(2): 323-8, 2007 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-17137710

RESUMO

Avemar (MSC) is a nontoxic fermented wheat germ extract demonstrated to significantly improve the survival rate in patients suffering from various malignancies. We investigated its effects in human HL-60 promyelocytic leukemia cells. After 24, 48, and 72 h of incubation, Avemar inhibited the growth of HL-60 cells with IC50 values of 400, 190, and 160 microg/ml, respectively. Incubation with MSC caused dose-dependent induction of apoptosis in up to 85% of tumor cells. In addition, Avemar attenuated the progression from G2-M to G0-G1 phase of the cell cycle and was also found to significantly reduce the in situ activity of ribonucleotide reductase, the key enzyme of de novo DNA synthesis. We conclude that Avemar exerts a number of beneficial effects which could support conventional chemotherapy of human malignancies.


Assuntos
Apoptose/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Extratos Vegetais/farmacologia , Ribonucleotídeo Redutases/antagonistas & inibidores , Divisão Celular/efeitos dos fármacos , Citidina/metabolismo , DNA/metabolismo , Células HL-60 , Humanos
8.
Exp Hematol ; 34(10): 1377-84, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16982330

RESUMO

OBJECTIVE: Resveratrol (3,4',5,-trihydroxystilbene, RV), an ingredient of wine, is an inhibitor of the proliferation-linked enzyme ribonucleotide reductase (RR) and shows a broad spectrum of cytotoxic effects against human cancer cells. In order to enhance these effects, we introduced additional hydroxyl moieties into the molecule. In the present study, the activity of a novel RV analog, 3,3',4,4',5,5'-hexahydroxystilbene (M8), was investigated in HL-60 human promyelocytic leukemia cells. METHODS: Cytotoxicity of M8 alone or in combination with Ara-C was assessed employing growth inhibition assays. Effects of M8 on nucleoside triphosphates (NTPs) and deoxynucleoside triphosphates (dNTPs) were examined by HPLC. The apoptotic potential of M8 and RV was compared using a specific double-staining method and inhibition of TNF-alpha-induced activation of NF-kappaB was studied. Cell-cycle distribution was analyzed by FACS. RESULTS: Addition of ascorbic acid decreased the IC(50) value of M8 from 6.25 microM to 2 microM. M8 depleted dATP and dTTP pools to 41% and 21% of control values, whereas dCTP pools increased to 199% of untreated controls. In addition, TTP, ATP, CTP, and GTP concentrations were decreased while UTP concentrations increased. M8 induced apoptosis at concentrations significantly lower than RV and could remarkably inhibit the activation of NF-kappaB. M8 arrested cells in the S phase of the cell cycle while depleting cells in the G2-M phase and exhibited synergistic combination effects when applied simultaneously with Ara-C. CONCLUSION: Due to these promising results, this novel polyhydroxylated stilbene derivative might become an additional option for the treatment of leukemia and therefore deserves further preclinical and in vivo testing.


Assuntos
Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Inibidores Enzimáticos/farmacologia , Leucemia Promielocítica Aguda/enzimologia , Pirogalol/análogos & derivados , Ribonucleotídeo Redutases/antagonistas & inibidores , Estilbenos/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Citarabina/farmacologia , Desoxirribonucleotídeos/metabolismo , Avaliação Pré-Clínica de Medicamentos , Células HL-60 , Humanos , Leucemia Promielocítica Aguda/tratamento farmacológico , NF-kappa B/metabolismo , Pirogalol/farmacologia , Resveratrol , Ribonucleotídeos/metabolismo , Estilbenos/química , Fator de Necrose Tumoral alfa/farmacologia , Vinho
9.
Exp Biol Med (Maywood) ; 230(2): 144-9, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15673563

RESUMO

Avemar (MSC) is a nontoxic fermented wheat germ extract demonstrated to have antitumor effects. Avemar has the potential to significantly improve the survival rate in patients suffering from malignant colon tumors. We studied its effects in the HT-29 human colon carcinoma cell line. Avemar had an inhibiting effect on colonies of HT-29 cells with an IC50 value of 118 microg/ml (7 days of incubation); this value could be decreased to 100 and 75 microg/ml in the presence of vitamin C. In the cell line examined, Avemar induced both necrosis and apoptosis, as demonstrated by Hoechst/propidium iodide staining. The incubation of cells with 3200 microg/ml Avemar for 24 hrs caused necrosis in 28% and the induction of apoptosis in 22% of the cells. Avemar inhibited the cell-cycle progression of HT-29 cells in the G1 phase of the cell cycle. In addition, Avemar inhibited the activity of the key enzyme of de novo DNA synthesis, ribonucleotide reductase. In addition, we determined the effects of Avemar on the activity of cyclooxygenase-1 and -2. Both enzymes were significantly inhibited by Avemar with IC50 values of 100 and 300 microg/ml, respectively. We outline new explanations for its antitumor activity, which might serve as the basis for further studies using Avemar.


Assuntos
Extratos Vegetais/farmacologia , Apoptose , Ácido Ascórbico/farmacologia , Ciclo Celular , Linhagem Celular Tumoral , Ciclo-Oxigenase 1 , Ciclo-Oxigenase 2 , DNA/metabolismo , Fase G1 , Humanos , Concentração Inibidora 50 , Proteínas de Membrana , Necrose , Propídio/farmacologia , Prostaglandina-Endoperóxido Sintases/metabolismo , Ribonucleotídeo Redutases/metabolismo , Triticum/metabolismo
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