RESUMO
BACKGROUND: The COVID-19 pandemic and related disruptive consequences in the economic, health, and educational sectors have impacted people's lives, contributing to a context of increased economic and social vulnerability. The pandemic has revealed and accentuated social inequalities and discrimination based on racial or ethnic origin. This study aimed to contribute to the promotion of the mental health and well-being of migrant populations living in Portugal via the definition of an analytical framework and recommendations emerging from the EQUALS4COVID19 project. METHODS: To gather information on the impact of the COVID-19 pandemic and resilience determinants among immigrants, a mixed-methods approach was implemented in 2022, combining a cross-sectional survey targeting immigrant adults in Portugal, focus groups with immigrants, focus groups with healthcare professionals, and in-depth individual interviews with stakeholders involved in the implementation of measures related to mental health and well-being during the pandemic. The analysis followed an integrated framework; quantitative data informed the script of qualitative data collection methods, and qualitative analysis informed the reinterpretation of quantitative data. RESULTS: The survey with 604 Brazilian and Cape Verdean immigrants revealed that gender (being a woman) was associated with both psychological distress and depression-related symptomatology and that the perception of discrimination was a major risk factor for psychological suffering, while perceived social support and individuals' resilience characteristics were protective factors. Qualitative data provided deeper insights into these findings, revealing the ways mental health is affected by social structures, such as gender and ethnic hierarchies. Migrants tend to work in precarious jobs requiring physical presence, which, together with dense housing conditions, puts them at higher risk of infection. The deterioration of the economic conditions of the general population has also increased the perception of ethnic-racial discrimination, which was found to be related to the increase in insecurity and anxiety-related symptomatology among the migrant population. Newly arrived migrants, with reduced support networks, experienced a greater sense of insecurity as well as concern and anguish regarding relatives who live far away, in their home country. Migrant women reported greater family-related distress, including work-life balance problems. CONCLUSIONS: Proposals to address mental health inequalities should be considered in the context of the necessary global changes both at the societal level and in the delivery of mental health services. Additionally, they should be considered with the active involvement of migrants, families, and communities in the design and delivery of mental health promotion and care processes.
Assuntos
COVID-19 , Saúde Mental , Humanos , Portugal/epidemiologia , Estudos Transversais , Masculino , Feminino , COVID-19/epidemiologia , COVID-19/psicologia , Adulto , Migrantes/psicologia , Migrantes/estatística & dados numéricos , Pessoa de Meia-Idade , Grupos Focais , Emigrantes e Imigrantes/psicologia , Emigrantes e Imigrantes/estatística & dados numéricos , Brasil/epidemiologia , Cabo Verde , Pesquisa Qualitativa , Adulto JovemRESUMO
This study aimed to understand how beliefs and attitudes regarding COVID-19 are associated with self-perceived changes in food consumption during lockdown between March 19 and May 2, 2020. We conducted a cross-sectional study with a non-probabilistic weighted sample of the Portuguese population. Data were collected using an online survey and telephone interviews. The association between agreement with sentences about food and COVID-19 and perceived changes in food consumption were assessed by multinomial logistic regression models. Overall, 5858 citizens were included, with a mean age of 38.2 (17.3) years. Exclusive agreement with the belief "SARS-CoV-2 can be transmitted by food" (27.5%) was associated with decreased odds of perceived positive changes (e.g., increased consumption of fruit and vegetables). Agreement only with the attitudinal sentence "I started to consume foods that may protect against COVID-19" (11.9%) was associated with positive perceived consumption changes (e.g., increasing fruit and vegetables, and decreasing soft drinks and snacks). Cumulative agreement (with both sentences; 10.6%) was also associated with mostly positive food consumption changes. Specific beliefs and attitudes regarding COVID-19 and food are associated with self-perceived changes in food consumption. Longitudinal research is needed to understand how beliefs and/or attitudes about the role of food in infectious diseases act as determinants of eating behavior modification.
Assuntos
COVID-19 , Adulto , Atitude , Controle de Doenças Transmissíveis , Estudos Transversais , Humanos , SARS-CoV-2RESUMO
Pitheciids are known for their frugivorous diets, but there has been no broad-scale comparison of fruit genera used by these primates that range across five geographic regions in South America. We compiled 31 fruit lists from data collected from 18 species (three Cacajao, six Callicebus, five Chiropotes, and four Pithecia) at 26 study sites in six countries. Together, these lists contained 455 plant genera from 96 families. We predicted that 1) closely related Chiropotes and Cacajao would demonstrate the greatest similarity in fruit lists; 2) pitheciids living in closer geographic proximity would have greater similarities in fruit lists; and 3) fruit genus richness would be lower in lists from forest fragments than continuous forests. Fruit genus richness was greatest for the composite Chiropotes list, even though Pithecia had the greatest overall sampling effort. We also found that the Callicebus composite fruit list had lower similarity scores in comparison with the composite food lists of the other three genera (both within and between geographic areas). Chiropotes and Pithecia showed strongest similarities in fruit lists, followed by sister taxa Chiropotes and Cacajao. Overall, pitheciids in closer proximity had more similarities in their fruit list, and this pattern was evident in the fruit lists for both Callicebus and Chiropotes. There was no difference in the number of fruit genera used by pitheciids in habitat fragments and continuous forest. Our findings demonstrate that pitheciids use a variety of fruit genera, but phylogenetic and geographic patterns in fruit use are not consistent across all pitheciid genera. This study represents the most extensive examination of pitheciid fruit consumption to date, but future research is needed to investigate the extent to which the trends in fruit genus richness noted here are attributable to habitat differences among study sites, differences in feeding ecology, or a combination of both.
Assuntos
Dieta/veterinária , Frutas/classificação , Herbivoria , Pitheciidae/fisiologia , Plantas/classificação , Animais , Ecossistema , Florestas , Geografia , FilogeografiaRESUMO
This study reports on the design, synthesis and antiparasitic activity of three new semi-synthetic naphthoquinones structurally related to the naturally-occurring lapachol and lapachone. Of the compounds tested, 3-(3-methylbut-1-en-1-yl)-1,4-dioxo-1,4-dihydronaphthalen-2-yl acetate (1) was the most active against Plasmodium falciparum among both natural and semi-synthetic naphthoquinones, showing potent and selective activity. Compound 1 was able to reduce the in vitro parasite burden, in vitro parasite cell cycle, as well as the blood parasitemia in Plasmodium berghei-infected mice. More importantly, infection reduction under compound 1-treatment was achieved without exhibiting mouse genotoxicity. Regarding the molecular mechanism of action, this compound inhibited the hemozoin crystal formation in P. falciparum treated cells, and this was further confirmed by observing that it inhibits the ß-hematin polymerization process similarly to chloroquine. Interestingly, this compound did not affect either mitochondria structure or cause DNA fragmentation in parasite treated cells. In conclusion, we identified a semi-synthetic antimalarial naphthoquinone closely related to isolapachol, which had stronger antimalarial activity than lapachol.
Assuntos
Antimaláricos/farmacologia , Naftoquinonas/farmacologia , Plasmodium berghei/efeitos dos fármacos , Plasmodium falciparum/efeitos dos fármacos , Acetilação , Animais , Camundongos , Camundongos Endogâmicos BALB C , Testes para MicronúcleosRESUMO
Infection by Trypanosoma cruzi, the aetiological agent of Chagas disease, causes an intense inflammatory reaction in several tissues, including the myocardium. We have previously shown that transplantation of bone marrow cells (BMC) ameliorates the myocarditis in a mouse model of chronic Chagas disease. We investigated the participation of BMC in lesion repair in the heart and skeletal muscle, caused by T. cruzi infection in mice. Infection with a myotropic T. cruzi strain induced an increase in the percentage of stem cells and monocytes in the peripheral blood, as well as in gene expression of chemokines SDF-1, MCP1, 2, and 3 in the heart and skeletal muscle. To investigate the fate of BMC within the damaged tissue, chimeric mice were generated by syngeneic transplantation of green fluorescent protein (GFP(+) ) BMC into lethally irradiated mice and infected with Trypanosoma cruzi. Migration of GFP(+) BMC to the heart and skeletal muscle was observed during and after the acute phase of infection. GFP(+) cardiomyocytes and endothelial cells were present in heart sections of chimeric chagasic mice. GFP(+) myofibres were observed in the skeletal muscle of chimeric mice at different time points following infection. In conclusion, BMC migrate and contribute to the formation of new resident cells in the heart and skeletal muscle, which can be detected both during the acute and the chronic phase of infection. These findings reinforce the role of BMC in tissue regeneration.
Assuntos
Células da Medula Óssea/citologia , Movimento Celular , Doença de Chagas/parasitologia , Coração/parasitologia , Músculo Esquelético/metabolismo , Miocárdio/citologia , Trypanosoma cruzi , Animais , Cardiomiopatia Chagásica/metabolismo , Doença de Chagas/patologia , Quimiocinas/metabolismo , Doença Crônica , Modelos Animais de Doenças , Feminino , Camundongos Endogâmicos C57BL , Músculo Esquelético/patologia , Miocárdio/metabolismo , Trypanosoma cruzi/fisiologiaRESUMO
We previously observed that physalins have immunomodulatory properties, as well as antileishmanial and antiplasmodial activities. Here, we investigated the anti-Trypanosoma cruzi activity of physalins B, D, F and G. We found that physalins B and F were the most potent compounds against trypomastigote and epimastigote forms of T. cruzi. Electron microscopy of trypomastigotes incubated with physalin B showed disruption of kinetoplast, alterations in Golgi apparatus and endoplasmic reticulum, followed by the formation of myelin-like figures, which were stained with MDC to confirm their autophagic vacuole identity. Physalin B-mediated alteration in Golgi apparatus was likely due to T. cruzi protease perturbation; however physalins did not inhibit activity of the trypanosomal protease cruzain. Flow cytometry examination showed that cell death is mainly caused by necrosis. Treatment with physalins reduced the invasion process, as well as intracellular parasite development in macrophage cell culture, with a potency similar to benznidazole. We observed that a combination of physalins and benznidazole has a greater anti-T. cruzi activity than when compounds were used alone. These results indicate that physalins, specifically B and F, are potent and selective trypanocidal agents. They cause structural alterations and induce autophagy, which ultimately lead to parasite cell death by a necrotic process.
Assuntos
Physalis/química , Secoesteroides/farmacologia , Tripanossomicidas/farmacologia , Trypanosoma cruzi/efeitos dos fármacos , Animais , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Estrutura Molecular , Secoesteroides/química , Tripanossomicidas/química , Trypanosoma cruzi/fisiologia , Trypanosoma cruzi/ultraestruturaRESUMO
Neotropical monkeys of the genera Cacajao, Chiropotes, and Pithecia (Pitheciidae) are considered to be highly arboreal, spending most of their time feeding and traveling in the upper canopy. Until now, the use of terrestrial substrates has not been analyzed in detail in this group. Here, we review the frequency of terrestrial use among pitheciin taxa to determine the ecological and social conditions that might lead to such behavior. We collated published and unpublished data from 14 taxa in the three genera. Data were gleaned from 53 published studies (including five on multiple pitheciin genera) and personal communications of unpublished data distributed across 31 localities. Terrestrial activity was reported in 61% of Pithecia field studies (11 of 18), in 34% of Chiropotes studies (10 of 29), and 36% of Cacajao studies (4 of 11). Within Pithecia, terrestrial behavior was more frequently reported in smaller species (e.g. P. pithecia) that are vertical clingers and leapers and make extensive use of the understory than in in the larger bodied canopy dwellers of the western Amazon (e.g. P. irrorata). Terrestrial behavior in Pithecia also occurred more frequently and lasted longer than in Cacajao or Chiropotes. An apparent association was found between flooded habitats and terrestrial activity and there is evidence of the development of a "local pattern" of terrestrial use in some populations. Seasonal fruit availability also may stimulate terrestrial behavior. Individuals also descended to the ground when visiting mineral licks, escaping predators, and responding to accidents such as a dropped infant. Overall, the results of this review emphasize that terrestrial use is rare among the pitheciins in general and is usually associated with the exploitation of specific resources or habitat types.
Assuntos
Comportamento Animal , Ecossistema , Pitheciidae , Animais , Feminino , Masculino , Comportamento Predatório , Estações do Ano , América do SulRESUMO
Preclinical studies in rodent models have been a pivotal role in human clinical research, but many of them fail in the translational process. Spontaneous tumors in pet dogs have the potential to bridge the gap between preclinical models and human clinical trials. Their natural occurrence in an immunocompetent system overcome the limitations of preclinical rodent models. Due to its reasonable cellular, molecular, and genetic homology to humans, the pet dog represents a valuable model to accelerate the translation of preclinical studies to clinical trials in humans, actually with benefits for both species. Moreover, their unique genetic features of breeding and breed-related mutations have contributed to assess and optimize therapeutics in individuals with different genetic backgrounds. This review aims to outline four main immunotherapy approaches - cancer vaccines, adaptive T-cell transfer, antibodies, and cytokines -, under research in veterinary medicine and how they can serve the clinical application crosstalk with humans.
Assuntos
Doenças do Cão/terapia , Imunoterapia/métodos , Neoplasias/terapia , Animais , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/imunologia , Modelos Animais de Doenças , Doenças do Cão/imunologia , Doenças do Cão/patologia , Cães , Avaliação Pré-Clínica de Medicamentos/métodos , Humanos , Neoplasias/imunologia , Neoplasias/veterinária , Roedores , Especificidade da Espécie , Pesquisa Translacional BiomédicaRESUMO
Over the last few decades, citizen awareness and perception of chemical products has been a topic of interest, particularly concerning national and international policy decision makers, expert/scientific platforms, and the European Union itself. To date, few qualitative studies on human biomonitoring have analysed communication materials, made recommendations in terms of biomonitoring surveillance, or asked for feedback in terms of specific biomonitoring methods. This paper provides in-depth insight on citizens' perceptions of knowledge of biomonitoring, impact of chemical exposure on daily life, and claims on how results of research should be used. Four semi-structured focus groups were held in Austria, Portugal, Ireland, and the United Kingdom (UK). The cross-sectional observational qualitative design of this study allows for better understanding of public concern regarding chemicals, application, and use of human biomonitoring. The main findings of this study include citizens' clear articulation on pathways of exposure, the demand on stakeholders for transparent decision-making, and sensitivity in communication of results to the public. Validated and trustful communication is perceived as key to empowering citizens to take action. The results can be used to facilitate decision-making and policy development, and feeds into the awareness needs of similar and future projects in human biomonitoring. Furthermore, it also brings to light ideas and concepts of citizens' in shaping collaborative knowledge between citizens', experts, scientists, and policy makers on equal terms.
Assuntos
Monitoramento Biológico , Confiança , Áustria , Participação da Comunidade , Estudos Transversais , Humanos , Irlanda , Portugal , Reino UnidoRESUMO
Recent advances in image technology, including significant gains in spatial resolution, have made realtime sequential ovarian evaluations possible in small rodents, allowing longitudinal (continued) studies of the ovarian cycle and reducing the required number of experimental animals. The aim of this study was to evaluate exogenous stimulated follicular growth in mice using high-resolution ultrasound technology. Female mice (n = 15) received a 5 IU intraperitoneal injection of equine chorionic gonadotropin (eCG) and 48 h later a 5 IU injection of human chorionic gonadotropin (hCG), and were allowed to mate thereafter. In experiment 1, animals (n = 7) were evaluated every 6 h, from 3 to 51 h after eCG injection, with an ultrasound biomicroscopy (UBM) equipped with a realtime 45 MHz microvisualization probe (RMV 707b). The ovaries were identified and follicular population quantified, and follicles were classified according to the diameter as small (≤449 µm) or large (≥450 µm). A significant change in the distribution of follicle population according to category was observed only 45 h after eCG injection (P < 0.05). In experiment 2, animals (n = 8) were evaluated every 2 h, from 2 h to 10 h after hCG treatment. The largest follicles reached a maximum size (596.7 ± 106.0 µm) 5.8 ± 2.3 h after hCG injection. As expected, the population of large follicles decreased thereafter, indicating the progress of ovulations, but large follicles were still detected late after treatment (10.1 ± 1.1 h). In conclusion, UBM can be used to evaluate follicle dynamics in superstimulated mice (C57BL/6 and BALB/c); significant changes in follicle distribution only occur at later stages after eCG stimulation; and hCG-induced ovulations may not occur synchronously in mice.
Assuntos
Microscopia Acústica/métodos , Folículo Ovariano/diagnóstico por imagem , Folículo Ovariano/crescimento & desenvolvimento , Ovulação/fisiologia , Animais , Gonadotropina Coriônica/administração & dosagem , Feminino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Fatores de TempoRESUMO
OBJECTIVES: In the present study we investigated the antinociceptive, anti-inflammatory and antipyretic effects of 7-hydroxycoumarin (7-HC) in animal models. METHODS: The effects of oral 7-HC were tested against acetic acid-induced writhing, formalin test, tail flick test, complete Freund's adjuvant (CFA)-induced hypernociception, carrageenan-induced paw oedema, lipopolysaccharide-induced fever and the rota rod test. KEY FINDINGS: 7-HC (3-60 mg/kg) produced a dose-related antinociception against acetic acid-induced writhing in mice and in the formalin test. In contrast, treatment with 7-HC did not prevent thermal nociception in the tail flick test. A single treatment with 7-HC, 60 mg/kg, produced a long-lasting antinociceptive effect against CFA-induced hypernociception, a chronic inflammatory pain stimulus. Notably, at 60 mg/kg per day over 4 days the administration of 7-HC produced a continuous antinociceptive effect against CFA-induced hypernociception. 7-HC (30-120 mg/kg) produced anti-inflammatory and antipyretic effects against carrageenan-induced inflammation and lipopolysaccharide-induced fever, respectively. Moreover, 7-HC was found to be safe with respect to ulcer induction. In the rota rod test, 7-HC-treated mice did not show any motor performance alterations. CONCLUSIONS: The prolonged antinociceptive and anti-inflammatory effects of 7-HC, in association with its low ulcerogenic activity, indicate that this molecule might be a good candidate for development of new drugs for the control of chronic inflammatory pain and fever.
Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Inflamação/tratamento farmacológico , Dor/tratamento farmacológico , Umbeliferonas/uso terapêutico , Doença Aguda , Administração Oral , Animais , Anti-Inflamatórios não Esteroides/administração & dosagem , Anti-Inflamatórios não Esteroides/efeitos adversos , Anti-Inflamatórios não Esteroides/farmacologia , Doença Crônica , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Edema/tratamento farmacológico , Febre/tratamento farmacológico , Masculino , Camundongos , Atividade Motora/efeitos dos fármacos , Medição da Dor , Ratos , Ratos Wistar , Umbeliferonas/administração & dosagem , Umbeliferonas/efeitos adversos , Umbeliferonas/farmacologiaRESUMO
We have previously demonstrated that both parasite genetic variability and host genetic background were important in determining the differential tissue distribution of the Col1.7G2 and JG T. cruzi monoclonal strains after artificial infections in mice. We observed that the JG strain was most prevalent in hearts of mouse lineages with the MHC haplotype H-2(d) (BALB/c and DBA2), while Col1.7G2 was predominant in hearts from C57BL/6 mice, which have the H-2(b) haplotype. To assess whether the MHC gene region indeed influenced tissue tropism of T. cruzi, we used the same two parasite strains to infect C57BL/6 (H-2(b)) and C57BLKS/J (H-2(d)) mice; the latter strain results from the introgression of DBA2 MHC region into the C57BL/6 background. We also performed ex vivo infections of cardiac explants from four congenic mice lineages with the H-2(b) and H-2(d) haplotypes arranged in two different genetic backgrounds: C57BLKS/J (H-2(d)) versus C57BL/6 (H-2(b)) and BALB/c (H-2(d)) versus BALB/B10-H2(b) (H-2(b)). In agreement with our former observations, Col1.7G2 was predominant in hearts from C57BL/6 mice (H-2(b)), but we observed a clear predominance of the JG strain in hearts from C57BLKS/J animals (H-2(d)). In the ex vivo experiments Col1.7G2 also prevailed in explants from H-2(b) animals while no predominance of any of the strains was observed in H-2(d) mice explants, regardless of the genetic background. These observations clearly demonstrate that the MHC region influences the differential tissue distribution pattern of infecting T. cruzi strains, which by its turn may be in a human infection the determinant for the clinical forms of the Chagas disease.
Assuntos
Interações Hospedeiro-Parasita/genética , Complexo Principal de Histocompatibilidade/genética , Tropismo , Trypanosoma cruzi/patogenicidade , Animais , Sequência de Bases , Primers do DNA , Haplótipos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos DBA , Especificidade de Órgãos , Reação em Cadeia da PolimeraseRESUMO
As células-tronco apresentam uma alta capacidade de autorregeneração, assim como, um potencial de diferenciação em uma variedade de tipos celulares. Estas células podem ser classificadas como embrionárias e adultas. Apesar de apresentar propriedades de células-tronco, as mesenquimais apresentam um certo grau de dificuldade no estabelecimento das culturas, podendo induzir a perda da expressão da enzima responsável pela imortalização ou enzima telomerase. A enzima telomerase é considerada um relógio biológico, um indicador que a senescência celular irá se instalar inevitavelmente. A questão mais atual e intrigante dos pesquisadores é se o suposto potencial de divisão, por um determinado período de tempo, das células-tronco cultivadas poderia levar ao acúmulo de alterações genéticas e epigenéticas, resultando em um processo neoplásico. Daí a importância do papel da citogenética humana no controle e monitoramento das células-tronco cultivadas que serão utilizadas na terapia em seres humanos. Alterações cromossômicas estruturais, tais como deleções, translocações e inversões, representam um mecanismo importante pelo qual as células cancerígenas desenvolvem-se gradualmente, uma vez que estas alterações cromossômicas podem levar a uma expressão anormal de muitos genes, podendo desencadear assim o processo neoplásico.
Stem cells have a high capacity of self-regeneration, as well as a potential to differentiate into several cell types. These cells can be classified as embryonic or adult. In spite of having inherent properties of stem cells, mesenchymal cells show a certain degree of difficulty to establish cultures. This might induce a loss of the expression of the telomerase enzyme which is considered to be a biological clock or an indicator of the senescence of the cells. The most current and intriguing question for researchers is whether the presumed division potential of cultivated stem cells, over a period of time could result in an accumulation of genetic alterations and consequently, in a neoplastic process. For this reason, cytogenetic techniques are very important to guarantee the control and safety of cultivated stem cells to be used in human therapy. Structural chromosomal alterations, such as for example, deletions, translocations and inversions represent an important mechanism by which cells might gradually transform in a neoplastic process. Thus, these chromosomal alterations could result in an abnormal expression of the genes and lead to cancer.
Assuntos
Humanos , Análise Citogenética , Cariotipagem , Técnicas de Diagnóstico Molecular , Técnicas de Cultura de Órgãos , Células-Tronco , Telomerase , Expansão de TecidoRESUMO
A doença de Chagas, que ocorre no México e nas Américas Central e do Sul, continua representando um grave problema de saúde pública. A prevalência global da infecção humana pelo Trypanosoma cruzi foi estimada em 16-18 milhões de casos no ano de 2005, sendo corrigida para aproximadamente 28 milhões de pessoas no ano de 2007, segundo a Organização Mundial de Saúde. A cardiopatia chagásica crônica é a forma mais comum de cardiomiopatia nas Américas Central e do Sul e a principal causa de morte por doença cardiovascular em áreas endêmicas. Até o momento não existe nenhum tratamento eficiente para esta doença a não ser o tratamento farmacológico ou o transplante cardíaco nos indivíduos que desenvolvem um quadro mais grave da doença. Trabalhos atuais têm mostrado o uso de células-tronco de várias origens em modelos animais e humanos de doenças do coração, como infarto do miocárdio, destacando uma melhora em aspectos como neovascularização, regeneração do músculo cardíaco, aumento da fração de ejeção e melhora na qualidade de vida dos indivíduos tratados. Estes dados induziram os pesquisadores a investigar os efeitos terapêuticos do transplante de células mononucleares de medula óssea em um modelo murino e em indivíduos chagásicos crônicos. Esta revisão tem por objetivo mostrar os trabalhos realizados usando a terapia celular na cardiopatia chagásica crônica.
Chagas' disease occurs throughout Mexico, Central and South America and still represents a serious threat to public health. The overall prevalence of infection by Trypanosoma cruzi was estimated at 16-18 million cases in 2005 and updated to approximately 28 million people in 2007, according to the World Health Organization. Chronic Chagas heart disease is the most common form of cardiomyopathy in Central and South America and one of the leading causes of death from cardiovascular disease in endemic areas. So far, there is no effective treatment for this disease except for heart transplantation in individuals who develop a more severe form the disease. Recent works have shown that the use of stem cells from various sources tested in animal models and in human heart diseases, including myocardial infarction, have resulted in an improvement in aspects such as vascularization, regeneration of the heart muscle, in ejection fraction and in quality of life of individuals treated. These data led researchers to investigate the effects of transplantation of bone marrow mononuclear cells in muriine models and chronic chagasic individuals. The present review aims to show the work carried out using cell therapy in chronic Chagas heart disease.
Assuntos
Humanos , Medula Óssea , Terapia Baseada em Transplante de Células e Tecidos , Doença de Chagas , Doença das Coronárias , Células-TroncoRESUMO
The family Boraginaceae is widely distributed in Brazil and in the Northeastern region some species are popularly used to treat symptoms of rheumatism, painful menstruation and dyspepsia. In this work we studied Cordia superba Cham. and C. rufescens A. DC., native from Brazilian Semi-arid region, in order to investigate their immunomodulatory activity. Six extracts were prepared from aerial parts of C. superba and C. rufescens. The cytotoxicity was evaluated using splenocytes from BALB/c mice. The immunomodulatory activity was determined by in vitro assays using activated mouse macrophages and lymphocytes. Peritoneal macrophages obtained from BALB/c mice were stimulated with IFN-gamma and LPS in the presence/absence of the samples. The NO production was measured indirectly through Griess method. Three samples inhibited the production of nitric oxide in values near 50 percent at a concentration of 100 µg/mL. To evaluate the effects of the extracts on lymphocytes, splenocytes from BALB/c mice were incubated with the samples and concanavalin A. Proliferation inhibition was determined by analysis of ³H-thymidine uptake. Samples from the two species had a strong inhibitory activity on lymphocyte proliferation and IL-2 production. Two chloroform extracts prepared from aerial parts of C. rufescens had the lowest IC50 values (7.6 and 11.0 µg/mL).
A família Boraginaceae é amplamente distribuída no Brasil e na região nordeste algumas espécies são usadas popularmente no tratamento de reumatismo, dores menstruais e dispepsias. Neste trabalho foram estudadas as espécies Cordia superba Cham. and C. rufescens A. DC., nativas da região semi-árida brasileira, objetivando investigar a atividade imunomoduladora. Seis extratos foram preparados a partir de partes aéreas das espécies. A citotoxicidade foi avaliada usando culturas de esplenócitos de camundongos BALB/c. A atividade imunomoduladora foi determinada por ensaios in vitro usando macrófagos e linfócitos murinos ativados. Macrófagos peritoneais obtidos de camundongos BALB/c foram estimulados com IFN-gama and LPS na presença/ausência das amostras. A produção de NO foi medida indiretamente através do método de Griess. Três amostras inibiram a produção de NO em valores próximos a 50 por cento (100 µg/mL). Os efeitos das amostras sobre os linfócitos foram avaliados cultivando esplenócitos de camundongos BALB/c em presença destas amostras e de concanavalina A. A proliferação foi determinada pela análise da incorporação de ³H-tritiada. Amostras de duas espécies apresentaram uma forte atividade inibidora sobre a proliferação de linfócitos e sobre a produção de IL-2. Dois extratos clorofórmicos (partes aéreas de C. rufescens) tiveram os menores valores de IC50 (7,6 and 11,0 µg/mL).
Assuntos
Boraginaceae/imunologia , Cordia/imunologia , Extratos VegetaisRESUMO
O desenvolvimento de técnicas de transplante de órgãos sólidos e de medula óssea foi um dos mais fascinantes avancos da medicina no século XX. A virada do século XXI testemunha um desdobramento também fascinante e promissor desta modalidade terapêutica: o uso de células-tronco para regenerar tecidos lesados outrora considerados irreparáveis. Resultados encorajadores de inúmeros estudos com animais de experimentacão impulsionaram grupos de diversos centros no mundo a iniciar estudos clínicos com transplante de células-tronco em várias doencas, particularmente as doencas cardiovasculares e neurológicas. Embora ainda estejamos algo distante de entender o mecanismo preciso pelo qual as células-tronco regeneram órgãos lesados, os estudos publicados até o presente momento, incluindo vários estudos envolvendo seres humanos, sugerem haver um benefício real com esta terapia. O presente artigo pretende abordar os aspectos relevantes da terapia celular em doencas cardiovasculares, incluindo conceitos básicos sobre células-tronco, e os principais estudos de animais de experimentacão e clínicos publicados até o presente.