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1.
Appetite ; 198: 107377, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38679064

RESUMO

Most instruments measuring nutrition literacy evaluate theoretical knowledge, not necessarily reflecting skills relevant to food choices. We aimed to develop and validate a photograph-based instrument to assess nutrition literacy (NUTLY) among adults in Portugal. NUTLY assesses the ability to distinguish foods with different nutritional profiles; from each of several combinations of three photographs (two foods with similar contents and one with higher content) participants are asked to identify the food with the highest energy/sodium content. The NUTLY version with 79 combinations, obtained after experts/lay people evaluations, was applied to a sample representing different age, gender and education groups (n = 329). Dimensionality was evaluated through latent trait models. Combinations with negative or with positive small factor loadings were excluded after critical assessment. Internal consistency was measured using Cronbach's alpha and construct validity by comparing NUTLY scores with those obtained in the Medical Term Recognition Test and the Newest Vital Sign (NVS), and across education and training in nutrition/health groups. The cut-off to distinguish adequate/inadequate nutrition literacy was defined through ROC analysis using the Youden index criterion, after performing a Latent class analysis which identified a two-class model to have the best goodness of fit. Test-retest reliability was assessed after one month (n = 158). The final NUTLY scale was unidimensional and included 48 combinations (energy: 33; sodium: 15; α = 0.74). Mean scores (±standard deviation) were highest among nutritionists (39.9 ± 4.4), followed by health professionals (38.5 ± 4.1) and declined with decreasing education (p < 0.001). Those with adequate nutrition literacy according to NVS showed higher NUTLY scores (37.9 ± 4.3 vs. 33.9 ± 6.9, p < 0.001). Adequate nutrition literacy was defined as a NUTLY score≥35 (sensitivity: 89.3%; specificity: 93.7%). Test-retest reliability was high (ICC = 0.77). NUTLY is a valid and reliable nutrition literacy measurement tool.


Assuntos
Letramento em Saúde , Fotografação , Humanos , Feminino , Masculino , Adulto , Reprodutibilidade dos Testes , Portugal , Pessoa de Meia-Idade , Adulto Jovem , Conhecimentos, Atitudes e Prática em Saúde , Idoso , Inquéritos e Questionários/normas , Adolescente
2.
Virol J ; 20(1): 275, 2023 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-38001529

RESUMO

This study investigates the presence of SARS-CoV-2 in indoor and outdoor environments in two cities in Norway between April and May 2022. With the lifting of COVID-19 restrictions in the country and a focus on vaccination, this research aims to shed light on the potential for virus transmission in various settings. Air sampling was conducted in healthcare and non-healthcare facilities, covering locations frequented by individuals across different age groups. The study found that out of 31 air samples, only four showed the presence of SARS-CoV-2 RNA by RT-qPCR, with no viable virus detected after RNAse pre-treatment. These positive samples were primarily associated with environments involving children and the elderly. Notably, sequencing revealed mutations associated with increased infectivity in one of the samples. The results highlight the importance of considering children as potential sources of virus transmission, especially in settings with prolonged indoor exposure. As vaccination coverage increases globally, and with children still representing a substantial unvaccinated population, the study emphasizes the need to re-implement mask-wearing mandates indoors and in public transport to reduce virus transmission. The findings have implications for public health strategies to control COVID-19, particularly in the face of new variants and the potential for increased transmission during the autumn and winter seasons.


Assuntos
COVID-19 , SARS-CoV-2 , Idoso , Humanos , Criança , SARS-CoV-2/genética , COVID-19/epidemiologia , RNA Viral/genética , Cidades , Noruega/epidemiologia
3.
BMC Public Health ; 23(1): 2421, 2023 12 05.
Artigo em Inglês | MEDLINE | ID: mdl-38053129

RESUMO

BACKGROUND: Diagnosis delay contributes to increased tuberculosis (TB) transmission and morbimortality. TB incidence has been decreasing in Portugal, but median patient delay (PD) has risen. Symptom valorisation may determine PD by influencing help-seeking behaviour. We aimed to analyse the association between symptom valorisation and PD, while characterising individuals who disregarded their symptoms. METHODS: A cross-sectional study was conducted among TB patients in Lisbon and Oporto in 2019 - 2021. Subjects who delayed seeking care because they did not value their symptoms or thought these would go away on their own were considered to have disregarded their symptoms. PD was categorised using a 21-day cut-off, and a 30-day cut-off for sensitivity analysis. We estimated the effect of symptom valorisation on PD through a directed acyclic graph. Then, a multivariable regression analysis characterised patients that disregarded their symptoms, adjusting for relevant variables. We fitted Poisson regression models to estimate crude and adjusted prevalence ratios (PR). RESULTS: The study included 75 patients. Median PD was 25 days (IQR 11.5-63.5), and 56.0% of participants had PD exceeding 21 days. Symptom disregard was reported by 38.7% of patients. Patients who did not value their symptoms had higher prevalence of PD exceeding 21 days compared to those who valued their symptoms [PR 1.59 (95% CI 1.05-2.42)]. The sensitivity analysis showed consistent point estimates but wider confidence intervals [PR 1.39 (95% CI 0.77-2.55)]. Being a smoker was a risk factor for symptom disregard [PR 2.35 (95% CI 1.14-4.82)], while living in Oporto [PR 0.35 (95% CI 0.16-0.75)] and having higher household incomes [PR 0.39 (95% CI 0.17-0.94)] were protective factors. CONCLUSIONS: These findings emphasise the importance of symptom valorisation in timely TB diagnosis. Patients who did not value their symptoms had longer PD, indicating a need for interventions to improve symptom recognition. Our findings also corroborate the importance of the socioeconomic determinants of health, highlighting tobacco as a risk factor both for TB and for PD.


Assuntos
Tuberculose Pulmonar , Tuberculose , Humanos , Aceitação pelo Paciente de Cuidados de Saúde , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/epidemiologia , Estudos Transversais , Portugal/epidemiologia , Diagnóstico Tardio , Tuberculose/epidemiologia , Inquéritos e Questionários
4.
Am J Transplant ; 22(2): 504-518, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34528383

RESUMO

The potential of adoptive cell therapy with regulatory T cells (Tregs) to promote transplant tolerance is under active exploration. However, the impact of specific transplant settings and protocols on Treg manufacturing is not well-delineated. Here, we compared the use of peripheral blood mononuclear cells (PBMCs) from patients before or after liver transplantation to the use of healthy control PBMCs to determine their suitability for Treg manufacture using ex vivo costimulatory blockade with belatacept. Despite liver failure or immunosuppressive therapy, the capacity for Treg expansion during the manufacturing process was preserved. These experiments did not identify performance or quality issues that disqualified the use of posttransplant PBMCs-the currently favored protocol design. However, as Treg input correlated with output, significant CD4-lymphopenia in both pre- and posttransplant patients limited Treg yield. We therefore turned to leukapheresis posttransplant to improve absolute yield. To make deceased donor use feasible, we also developed protocols to substitute splenocytes for PBMCs as allostimulators. In addition to demonstrating that this Treg expansion strategy works in a liver transplant context, this preclinical study illustrates how characterizing cellular input populations and their performance can both inform and respond to clinical trial design and Treg manufacturing requirements.


Assuntos
Transplante de Fígado , Linfócitos T Reguladores , Abatacepte/farmacologia , Humanos , Imunossupressores/farmacologia , Imunossupressores/uso terapêutico , Leucócitos Mononucleares , Transplantados , Tolerância ao Transplante
5.
Indoor Air ; 32(8): e13083, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36040285

RESUMO

This systematic review aims to present an overview of the current aerosol sampling methods (and equipment) being used to investigate the presence of SARS-CoV-2 in the air, along with the main parameters reported in the studies that are essential to analyze the advantages and disadvantages of each method and perspectives for future research regarding this mode of transmission. A systematic literature review was performed on PubMed/MEDLINE, Web of Science, and Scopus to assess the current air sampling methodologies being applied to SARS-CoV-2. Most of the studies took place in indoor environments and healthcare settings and included air and environmental sampling. The collection mechanisms used were impinger, cyclone, impactor, filters, water-based condensation, and passive sampling. Most of the reviewed studies used RT-PCR to test the presence of SARS-CoV-2 RNA in the collected samples. SARS-CoV-2 RNA was detected with all collection mechanisms. From the studies detecting the presence of SARS-CoV-2 RNA, fourteen assessed infectivity. Five studies detected viable viruses using impactor, water-based condensation, and cyclone collection mechanisms. There is a need for a standardized protocol for sampling SARS-CoV-2 in air, which should also account for other influencing parameters, including air exchange ratio in the room sampled, relative humidity, temperature, and lighting conditions.


Assuntos
Poluição do Ar em Ambientes Fechados , COVID-19 , Humanos , RNA Viral , Aerossóis e Gotículas Respiratórios , SARS-CoV-2 , Água
6.
Br J Nutr ; 124(10): 1093-1101, 2020 11 28.
Artigo em Inglês | MEDLINE | ID: mdl-32513318

RESUMO

Street food is popular in Eastern Europe, but its diversity and nutritional value are unknown. This study aimed to characterise the street food environment in Chisinau, Moldova, including the vending sites and vendors, food availability and nutritional composition of foods and beverages. All street food vending sites (single point of sale) located in a 1-km buffer centred on the main public market were systematically selected (n 439; n 328 participants). Data on vending sites' characteristics (mobility, type of physical set-up and access to electricity), operating periods and food availability were collected. Samples of the most commonly available foods of unknown composition were collected (twenty-eight home-made and twenty-four industrial). Macronutrients, Na and K were quantified through chemical analysis. Fruits, beverages and food other than fruits were available in 2·5, 74·3 and 80·8 % of the vending sites, respectively. Among the latter, 66·4 % sold only industrial foods (e.g. pretzels, biscuits, wafers, chocolate and ice cream), 21·5 % only home-made (e.g. savoury and sweet pastries) and 12·1 % both. Home-made foods presented larger serving sizes and energy/serving (median kJ/serving: 1312·5 v. 670·3, P = 0·022); industrial foods were more energy-dense (median kJ/100 g: 1797·0 v. 1269·8, P = 0·002). High SFA, trans-fat and Na contents were found, reaching 10·9 g/serving, 1·4 g/serving and 773·7 mg/serving, respectively. Soft drinks and alcoholic beverages were available in 80·7 and 42·0 % of the vending sites selling beverages, respectively. Concluding, industrial snacks and home-made pastries high in Na and unhealthy fat were frequent in Chisinau. Prevention of diet-related diseases in Moldova may benefit from the improvement of the nutritional profile of street food.


Assuntos
Comércio , Alimentos , Valor Nutritivo , Bebidas/análise , Estudos Transversais , Ingestão de Energia , Feminino , Análise de Alimentos , Frutas , Humanos , Masculino , Moldávia , Nutrientes/análise , Tamanho da Porção de Referência , Lanches , Sódio na Dieta/análise , Ácidos Graxos trans/análise
7.
Nutr Health ; 25(1): 37-46, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30522397

RESUMO

BACKGROUND:: A nutrition transition is occurring in the urban areas of developing countries, where street food makes an important contribution to daily food intake. AIM:: We aimed to characterise street food offer in Maputo, Mozambique, and to evaluate the nutritional composition of the most common homemade foods. METHODS:: A cross-sectional study was conducted in 2014. Streets in the surroundings (500 m buffer) of randomly selected public transport stops in KaMpfumu district, Maputo, were canvassed to identify all street food vending sites ( n = 968). Information regarding vending site characteristics and the food offered was gathered through interview and observation. Samples ( n = 80) of the most common homemade foods were collected for laboratorial analysis. RESULTS:: Most street food vending sites identified were stationary (77.4%) and sold exclusively industrial food (51.9%). Frequency of fruit, beverages and food other than fruit was 24.5%, 32.5% and 73.9%, respectively. Fried cakes were the most energy-dense (430 kcal/100 g), and richest in fats (21.0g/100 g) and carbohydrates (53.4 g/100 g). The richest sources of protein were the stewed meat/fish/liver dishes (10.7-11.6 g/100 g). Fried cakes showed the lowest sodium and potassium content (90 mg/100 g and 81 mg/100 g, respectively) whereas hamburgers exhibited the highest content of those micronutrients (455 mg/100 g and 183 mg/100 g, respectively). Stewed liver dishes presented the highest sodium/potassium ratio (11.95). Fried snacks presented the highest trans-fatty acid content (0.20 g/100 g). CONCLUSIONS:: Street food in Maputo is abundant and scattered throughout the urban district, exhibiting high variability in the nutritional composition of homemade foods. Public health policies should be targeted to improve the street food offer, promoting nutrient-dense foods and the reduction of added salt.


Assuntos
Comércio , Dieta , Abastecimento de Alimentos , Nutrientes/análise , Valor Nutritivo , População Urbana , Bebidas , Cidades , Estudos Transversais , Países em Desenvolvimento , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Humanos , Carne , Moçambique , Nutrientes/administração & dosagem , Estado Nutricional , Potássio na Dieta/administração & dosagem , Potássio na Dieta/análise , Alimentos Marinhos , Lanches , Sódio na Dieta/administração & dosagem , Sódio na Dieta/análise , Ácidos Graxos trans/administração & dosagem , Ácidos Graxos trans/análise
8.
J Neurosci ; 37(10): 2776-2794, 2017 03 08.
Artigo em Inglês | MEDLINE | ID: mdl-28123081

RESUMO

Transcriptional deregulation and changes in mitochondrial bioenergetics, including pyruvate dehydrogenase (PDH) dysfunction, have been described in Huntington's disease (HD). We showed previously that the histone deacetylase inhibitors (HDACIs) trichostatin A and sodium butyrate (SB) ameliorate mitochondrial function in cells expressing mutant huntingtin. In this work, we investigated the effect of HDACIs on the regulation of PDH activity in striatal cells derived from HD knock-in mice and YAC128 mice. Mutant cells exhibited decreased PDH activity and increased PDH E1alpha phosphorylation/inactivation, accompanied by enhanced protein levels of PDH kinases 1 and 3 (PDK1 and PDK3). Exposure to dichloroacetate, an inhibitor of PDKs, increased mitochondrial respiration and decreased production of reactive oxygen species in mutant cells, emphasizing PDH as an interesting therapeutic target in HD. Treatment with SB and sodium phenylbutyrate, another HDACI, recovered cell viability and overall mitochondrial metabolism in mutant cells. Exposure to SB also suppressed hypoxia-inducible factor-1 (HIF-1α) stabilization and decreased the transcription of the two most abundant PDK isoforms, PDK2 and PDK3, culminating in increased PDH activation in mutant cells. Concordantly, PDK3 knockdown improved mitochondrial function, emphasizing the role of PDK3 inactivation on the positive effects achieved by SB treatment. YAC128 mouse brain presented higher mRNA levels of PDK1-3 and PDH phosphorylation and decreased energy levels that were significantly ameliorated after SB treatment. Furthermore, enhanced motor learning and coordination were observed in SB-treated YAC128 mice. These results suggest that HDACIs, particularly SB, promote the activity of PDH in the HD brain, helping to counteract HD-related deficits in mitochondrial bioenergetics and motor function.SIGNIFICANCE STATEMENT The present work provides a better understanding of mitochondrial dysfunction in Huntington's disease (HD) by showing that the pyruvate dehydrogenase (PDH) complex is a promising therapeutic target. In particular, the histone deacetylase inhibitor sodium butyrate (SB) may indirectly (through reduced hypoxia-inducible factor 1 alpha stabilization) decrease the expression of the most abundant PDH kinase isoforms (e.g., PDK3), ameliorating PDH activity and mitochondrial metabolism and further affecting motor behavior in HD mice, thus constituting a promising agent for HD neuroprotective treatment.


Assuntos
Inibidores de Histona Desacetilases/administração & dosagem , Doença de Huntington/tratamento farmacológico , Doença de Huntington/metabolismo , Neurônios/enzimologia , Fármacos Neuroprotetores/administração & dosagem , Complexo Piruvato Desidrogenase/metabolismo , Animais , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Masculino , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Neurônios/efeitos dos fármacos , Resultado do Tratamento
9.
Calcif Tissue Int ; 102(2): 227-250, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29079995

RESUMO

Cancer-induced bone disease is a major source of morbidity and mortality in cancer patients. Thus, effective bone-targeted therapies are essential to improve disease-free, overall survival and quality of life of cancer patients with bone metastases. Depending of the cancer-type, bone metastases mainly involve the modulation of osteoclast and/or osteoblast activity by tumour cells. To inhibit metastatic bone disease effectively, it is imperative to understand its underlying mechanisms and identify the target cells for therapy. If the aim is to prevent bone metastasis, it is essential to target not only bone metastatic features in the tumour cells, but also tumour-nurturing bone microenvironment properties. The currently available bone-targeted agents mainly affect osteoclasts, inhibiting bone resorption (e.g. bisphosphonates, denosumab). Some agents targeting osteoblasts begin to emerge which target osteoblasts (e.g. romosozumab), activating bone formation. Moreover, certain drugs initially thought to target only osteoclasts are now known to have a dual action (activating osteoblasts and inhibiting osteoclasts, e.g. proteasome inhibitors). This review will focus on the evolution of bone-targeted therapies for the treatment of cancer-induced bone disease, summarizing preclinical and clinical findings obtained with anti-resorptive and bone anabolic therapies.


Assuntos
Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/secundário , Antagonistas de Androgênios/uso terapêutico , Bortezomib/uso terapêutico , Catepsina K/antagonistas & inibidores , Denosumab/uso terapêutico , Difosfonatos/uso terapêutico , Humanos , Integrinas/antagonistas & inibidores , Terapia de Alvo Molecular , Inibidores de Proteassoma/uso terapêutico , Proteínas Proto-Oncogênicas pp60(c-src)/antagonistas & inibidores , Compostos Radiofarmacêuticos/uso terapêutico , Serina-Treonina Quinases TOR/antagonistas & inibidores
10.
J Immunol ; 197(8): 3059-3068, 2016 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-27619996

RESUMO

Human Vγ9Vδ2 T cells recognize in a butyrophilin 3A/CD277-dependent way microbial (E)-4-hydroxy-3-methyl-but-2-enyl pyrophosphate (HMBPP) or endogenous pyrophosphates (isopentenyl pyrophosphate [IPP]). Nitrogen-bisphosphonates such as zoledronic acid (ZOL) trigger selective γδ T cell activation because they stimulate IPP production in monocytes by inhibiting the mevalonate pathway downstream of IPP synthesis. We performed a comparative analysis of the capacity of purified monocytes, neutrophils, and CD4 T cells to serve as accessory cells for Vγ9Vδ2 T cell activation in response to three selective but mechanistically distinct stimuli (ZOL, HMBPP, agonistic anti-CD277 mAb). Only monocytes supported γδ T cell expansion in response to all three stimuli, whereas both neutrophils and CD4 T cells presented HMBPP but failed to induce γδ T cell expansion in the presence of ZOL or anti-CD277 mAb. Preincubation of accessory cells with the respective stimuli revealed potent γδ T cell-stimulating activity of ZOL- or anti-CD277 mAb-pretreated monocytes, but not neutrophils. In comparison with monocytes, ZOL-pretreated neutrophils produced little, if any, IPP and expressed much lower levels of farnesyl pyrophosphate synthase. Exogenous IL-18 enhanced the γδ T cell expansion with all three stimuli, remarkably also in response to CD4 T cells and neutrophils preincubated with anti-CD277 mAb or HMBPP. Our study uncovers unexpected differences between monocytes and neutrophils in their accessory function for human γδ T cells and underscores the important role of IL-18 in driving γδ T cell expansion. These results may have implications for the design of γδ T cell-based immunotherapeutic strategies.


Assuntos
Antígenos CD/metabolismo , Butirofilinas/metabolismo , Linfócitos T CD4-Positivos/imunologia , Monócitos/imunologia , Neutrófilos/imunologia , Linfócitos T/imunologia , Anticorpos Bloqueadores/imunologia , Antígenos CD/imunologia , Butirofilinas/imunologia , Células Cultivadas , Difosfonatos/imunologia , Geraniltranstransferase/metabolismo , Hemiterpenos/imunologia , Humanos , Imidazóis/imunologia , Interleucina-18/metabolismo , Ativação Linfocitária , Ácido Mevalônico/metabolismo , Organofosfatos/imunologia , Compostos Organofosforados/imunologia , Receptores de Antígenos de Linfócitos T gama-delta/metabolismo , Ácido Zoledrônico
11.
Health Res Policy Syst ; 16(1): 102, 2018 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-30376876

RESUMO

OBJECTIVE: To describe the implementation, main intervention areas and initial results of the Integrated Strategy for the Promotion of Healthy Eating (EIPAS) in Portugal. METHODS: EIPAS was published as a Law, in December of 2017, as a result of a collaboration between several ministries, including the Finance, Internal Affairs, Education, Health, Economy, Agriculture, and Sea Ministries, aiming at improving the dietary habits of the Portuguese population. The working group, led by the Ministry of Health, developed this strategy for over a year. The framework produced was based on WHO and European Commission recommendations as well as on relevant data from the last Portuguese dietary intake survey (2015/2016). EIPAS also reflects the results of a public hearing, including the food industry, among others, and the experience gathered, since 2012, through the National Programme for the Promotion of Healthy Eating. It considers the 'health in all policies' challenge set by WHO and has four different strategic areas, namely (1) creation of healthier food environments, (2) improvement of the quality and accessibility of healthy food choices for consumers, (3) promotion and development of literacy, in order to encourage healthy food choices, and (4) promotion of innovation and entrepreneurship. In order to achieve these goals, a set of 51 actions was established and assigned to the seven ministries involved. RESULTS: Under the scope of this strategy, Portugal has already implemented several actions, including (1) definition of standards for food availability at all public healthcare institutions; (2) implementation of a sugar tax on sweetened beverages; (3) implementation of a voluntary agreement with the food industry sector for food reformulation (work in progress); (4) design of a proposal for an interpretative model of front-of-pack food labelling; (5) improvement of the nutritional quality of food aid programmes for low-income groups; and (6) regulation of marketing of unhealthy foods to children. CONCLUSIONS: For the first time, Portugal has a nutrition policy based on the WHO concept of 'health in all policies' and on the national data on food intake. The implementing process of all 51 actions and the inherent complexities and difficulties found so far have made this process be an authentic political and social laboratory that deserves to be followed.


Assuntos
Dieta Saudável , Comportamento Alimentar , Órgãos Governamentais , Promoção da Saúde/métodos , Política Nutricional , Adulto , Bebidas , Criança , Açúcares da Dieta , Assistência Alimentar , Indústria Alimentícia , Rotulagem de Alimentos , Regulamentação Governamental , Humanos , Marketing , Valor Nutritivo , Saúde Pública , Impostos
12.
Biotechnol Bioeng ; 113(5): 1102-12, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26551676

RESUMO

In recent years, dynamic metabolic flux analysis (DMFA) has been developed in order to evaluate the dynamic evolution of the metabolic fluxes. Most of the proposed approaches are dedicated to exactly determined or overdetermined systems. When an underdetermined system is considered, the literature suggests the use of dynamic flux balance analysis (DFBA). However the main challenge of this approach is to determine an appropriate objective function, which remains valid over the whole culture. In this work, we propose an alternative dynamic metabolic flux analysis based on convex analysis, DMFCA, which allows the determination of bounded intervals for the fluxes using the available knowledge of the metabolic network and information provided by the time evolution of extracellular component concentrations. Smoothing splines and mass balance differential equations are used to estimate the time evolution of the uptake and excretion rates from this experimental data. The main advantage of the proposed procedure is that it does not require additional constraints or objective functions, and provides relatively narrow intervals for the intracellular metabolic fluxes. DMFCA is applied to experimental data from hybridoma HB58 cell perfusion cultures, in order to investigate the influence of the operating mode (batch and perfusion) on the metabolic flux distribution.


Assuntos
Hibridomas/metabolismo , Análise do Fluxo Metabólico , Redes e Vias Metabólicas , Algoritmos , Animais , Reatores Biológicos , Técnicas de Cultura de Células , Simulação por Computador , Hibridomas/citologia , Camundongos , Modelos Biológicos , Perfusão , Ratos
13.
Breast Cancer Res ; 17: 101, 2015 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-26243145

RESUMO

INTRODUCTION: The immune system plays a major role in cancer progression. In solid tumors, 5-40 % of the tumor mass consists of tumor-associated macrophages (TAMs) and there is usually a correlation between the number of TAMs and poor prognosis, depending on the tumor type. TAMs usually resemble M2 macrophages. Unlike M1-macrophages which have pro-inflammatory and anti-cancer functions, M2-macrophages are immunosuppressive, contribute to the matrix-remodeling, and hence favor tumor growth. The role of TAMs is not fully understood in breast cancer progression. METHODS: Macrophage infiltration (CD68) and activation status (HLA-DRIIα, CD163) were evaluated in a large cohort of human primary breast tumors (562 tissue microarray samples), by immunohistochemistry and scored by automated image analysis algorithms. Survival between groups was compared using the Kaplan-Meier life-table method and a Cox multivariate proportional hazards model. Macrophage education by breast cancer cells was assessed by ex vivo differentiation of peripheral blood mononuclear cells (PBMCs) in the presence or absence of breast cancer cell conditioned media (MDA-MB231, MCF-7 or T47D cell lines) and M1 or M2 inducing cytokines (respectively IFN-γ, IL-4 and IL-10). Obtained macrophages were analyzed by flow cytometry (CD14, CD16, CD64, CD86, CD200R and CD163), ELISA (IL-6, IL-8, IL-10, monocyte colony stimulating factor M-CSF) and zymography (matrix metalloproteinase 9, MMP-9). RESULTS: Clinically, we found that high numbers of CD163(+) M2-macrophages were strongly associated with fast proliferation, poor differentiation, estrogen receptor negativity and histological ductal type (p<0.001) in the studied cohort of human primary breast tumors. We demonstrated ex vivo that breast cancer cell-secreted factors modulate macrophage differentiation toward the M2 phenotype. Furthermore, the more aggressive mesenchymal-like cell line MDA-MB231, which secretes high levels of M-CSF, skews macrophages toward the more immunosuppressive M2c subtype. CONCLUSIONS: This study demonstrates that human breast cancer cells influence macrophage differentiation and that TAM differentiation status correlates with recurrence free survival, thus further emphasizing that TAMs can similarly affect therapy efficacy and patient outcome.


Assuntos
Neoplasias da Mama/patologia , Leucócitos Mononucleares/patologia , Macrófagos/patologia , Neoplasias da Mama/metabolismo , Diferenciação Celular/fisiologia , Linhagem Celular Tumoral , Proliferação de Células/fisiologia , Citocinas/metabolismo , Feminino , Humanos , Leucócitos Mononucleares/metabolismo , Fator Estimulador de Colônias de Macrófagos/metabolismo , Macrófagos/metabolismo , Metaloproteinase 9 da Matriz/metabolismo
15.
BMC Cancer ; 15: 4, 2015 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-25588705

RESUMO

BACKGROUND: Tumour stromal macrophages differentiate to tumour-associated macrophages (TAMs) with characteristics of immunosuppressive M2-type macrophages, having a central role in promoting tumour vascularisation, cancer cell dissemination and in suppressing anti-cancer immune responses. Bisphosphonates (BPs) are a group of drugs commonly used as anti-resorptive agents. Further, nitrogen containing BPs like Zoledronate (ZOL), are known to cause unspecific inflammatory reactions hence the hypothesis that its use could modulate TAMs polarization toward a more inflammatory phenotype. METHODS: We studied the in vitro polarization of J774 murine macrophages upon culture in 4T1 breast cancer cell-conditioned medium (4T1CM) and stimulation with LPS and free and liposome-encapsulated bisphosphonates. RESULTS: In this system, breast cancer soluble factors reduced the pro-inflammatory activation of macrophages but increased the secretion of matrix metalloproteinases (MMPs). In the presence of 4T1CM, a non-cytotoxic dose of liposome-encapsulated ZOL (ZOL-LIP) enhanced the expression of iNOS and TNF-α, markers of M1 activation, but did not diminish the expression of M2-type markers. In contrast, clodronate treatment either as a free drug (CLO) or liposome-encapsulated (CLO-LIP) decreased the expression of the M1-type markers and was highly cytotoxic to the macrophages. CONCLUSIONS: Breast cancer cells soluble factors modulate macrophages toward M2 activation state. Bisphosphonates may be applied to counteract this modulation. We propose that ZOL-LIP may be suitable for favouring cytotoxic immune responses by TAMs in breast cancer, whereas CLO-LIP may be appropriate for TAM depletion.


Assuntos
Neoplasias da Mama/metabolismo , Meios de Cultivo Condicionados/farmacologia , Difosfonatos/farmacologia , Imidazóis/farmacologia , Macrófagos/efeitos dos fármacos , Animais , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Feminino , Humanos , Lipossomos , Macrófagos/citologia , Macrófagos/imunologia , Metaloproteinases da Matriz/metabolismo , Camundongos , Óxido Nítrico Sintase Tipo II/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Ácido Zoledrônico
17.
Nucleic Acids Res ; 41(7): 3986-99, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23408853

RESUMO

The homeobox transcription factor CDX2 plays a crucial role in intestinal cell fate specification, both during normal development and in tumorigenic processes involving intestinal reprogramming. The CDX2 regulatory network is intricate, but it has not yet been fully uncovered. Through genome-wide screening of a 3D culture system, the RNA-binding protein MEX3A was identified as putatively involved in CDX2 regulation; therefore, its biological relevance was addressed by setting up cell-based assays together with expression studies in murine intestine. We demonstrate here that MEX3A has a repressive function by controlling CDX2 levels in gastric and colorectal cellular models. This is dependent on the interaction with a specific binding determinant present in CDX2 mRNA 3'untranslated region. We have further determined that MEX3A impairs intestinal differentiation and cellular polarization, affects cell cycle progression and promotes increased expression of intestinal stem cell markers, namely LGR5, BMI1 and MSI1. Finally, we show that MEX3A is expressed in mouse intestine, supporting an in vivo context for interaction with CDX2 and modulation of stem cell properties. Therefore, we describe a novel CDX2 post-transcriptional regulatory mechanism, through the RNA-binding protein MEX3A, with a major impact in intestinal differentiation, polarity and stemness, likely contributing to intestinal homeostasis and carcinogenesis.


Assuntos
Regulação para Baixo , Proteínas de Homeodomínio/genética , Mucosa Intestinal/metabolismo , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Regiões 3' não Traduzidas , Sequência de Bases , Sítios de Ligação , Fator de Transcrição CDX2 , Células CACO-2 , Técnicas de Cultura de Células , Diferenciação Celular , Linhagem Celular Tumoral , Proteínas de Homeodomínio/metabolismo , Humanos , Intestinos/citologia , Dados de Sequência Molecular , Fenótipo , Células-Tronco/metabolismo
18.
Mol Cancer ; 13: 265, 2014 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-25496233

RESUMO

BACKGROUND: Anti-resorptive bisphosphonates (BP) are used for the treatment of osteoporosis and bone metastases. Clinical studies indicated a benefit in survival and tumor relapse in subpopulations of breast cancer patients receiving zoledronic acid, thus stimulating the debate about its anti-tumor activity. Amino-bisphosphonates in nM concentrations inhibit farnesyl pyrophosphate synthase leading to accumulation of isopentenyl pyrophosphate (IPP) and the ATP/pyrophosphate adduct ApppI, which induces apoptosis in osteoclasts. For anti-tumor effects µM concentrations are needed and a sensitizer for bisphosphonate effects would be beneficial in clinical anti-tumor applications. We hypothesized that enhancing intracellular pyrophosphate accumulation via inhibition of probenecid-sensitive channels and transporters would sensitize tumor cells for bisphosphonates anti-tumor efficacy. METHOD: MDA-MB-231, T47D and MCF-7 breast cancer cells were treated with BP (zoledronic acid, risedronate, ibandronate, alendronate) and the pyrophosphate channel inhibitors probenecid and novobiocin. We determined cell viability and caspase 3/7 activity (apoptosis), accumulation of IPP and ApppI, expression of ANKH, PANX1, ABCC1, SLC22A11, and the zoledronic acid target gene and tumor-suppressor KLF2. RESULTS: Treatment of MDA-MB-231 with BP induced caspase 3/7 activity, with zoledronic acid being the most effective. In MCF-7 and T47D either BP markedly suppressed cell viability with only minor effects on apoptosis. Co-treatment with probenecid enhanced BP effects on cell viability, IPP/ApppI accumulation as measurable in MCF-7 and T47D cells, caspase 3/7 activity and target gene expression. Novobiocin co-treatment of MDA-MB-231 yielded identical results on viability and apoptosis compared to probenecid, rendering SLC22A family members as candidate modulators of BP effects, whereas no such evidence was found for ANKH, ABCC1 and PANX1. CONCLUSIONS: In summary, we demonstrate effects of various bisphosphonates on caspase 3/7 activity, cell viability and expression of tumor suppressor genes in breast cancer cells. Blocking probenecid and novobiocin-sensitive channels and transporters enhances BP anti-tumor effects and renders SLC22A family members as good candidates as BP modulators. Further studies will have to unravel if treatment with such BP-sensitizers translates into preclinical and clinical efficacy.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Difosfonatos/farmacologia , Probenecid/farmacologia , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Neoplasias Ósseas/tratamento farmacológico , Neoplasias Ósseas/metabolismo , Neoplasias da Mama/metabolismo , Caspase 3/metabolismo , Caspase 7/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Conexinas/metabolismo , Ácido Etidrônico/análogos & derivados , Ácido Etidrônico/farmacologia , Feminino , Hemiterpenos/farmacologia , Humanos , Ácido Ibandrônico , Imidazóis/farmacologia , Células MCF-7 , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Compostos Organofosforados/farmacologia , Osteoclastos/efeitos dos fármacos , Osteoclastos/metabolismo , Proteínas de Transporte de Fosfato/metabolismo , Ácido Risedrônico , Ácido Zoledrônico
20.
Chemosphere ; 352: 141355, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38331261

RESUMO

Firefighters perform high-risk activities and during the course of their functions are highly exposed to a wide range of occupational hazards, including air pollution. Thus, this study aimed to assess the exposure of firefighters in prescribed wildland fires and their occupational exposure, as well as to identify and chemically characterise the particles collected during wildland firefighting and inside fire stations. Exposure to wildfire smoke was evaluated in 7 prescribed fires in Portugal, 2 in the north and 5 in the south of Viseu district. The concentrations of PM2.5, NO2, SO2, CO and VOCs were monitored and exceedances to occupational exposure limit values were identified. Moreover, the chemical composition of PM2.5 was analysed. The results showed that firefighters were exposed to high concentrations of these pollutants during prescribed fires and that, in some cases, exceeded occupational exposure limits, both for time-weighted average concentrations for an 8-h working day (a time-weighted average, TWA) of PM2.5, and for short-term exposure values (STEL) of NO2 and SO2. Despite being exposed to very high concentrations of CO, no exceedances to the occupational exposure values were observed. FT-IR and SEM-EDS allowed to chemically characterise the composition of the particles collected inside the fire stations and also during wildland fires, identifying mainly quartz, aluminium and magnesium silicates, characteristic of earth's crust constituents. and also, fibres that have undergone combustion. Concluding, firefighters' exposure to high concentrations of harmful pollutants, can lead to the degradation of their respiratory health. It is therefore extremely important to increase existing knowledge and conduct further studies, especially longitudinal ones, that can assess their lung function. This will allow an understanding of the impacts of smoke on firefighters' health and develop effective strategies to protect them during wildland firefighting operations.


Assuntos
Poluentes Ocupacionais do Ar , Poluentes Ambientais , Bombeiros , Exposição Ocupacional , Humanos , Poluentes Ocupacionais do Ar/análise , Poluentes Ambientais/análise , Dióxido de Nitrogênio/análise , Exposição Ocupacional/análise , Portugal , Fumaça/análise , Espectroscopia de Infravermelho com Transformada de Fourier
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