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1.
Cancer Invest ; 41(10): 830-836, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37962565

RESUMO

Introduction melanoma patients who become stage III after a positive sentinel node biopsy (SNB) may have several patterns of recurrence patients and methods retrospective analysis of melanoma patients who have undergone SNB in a single institution from 2000 to 2015. Results There were 111 recurrences (45.1%) among 246 (20.3%) SNB positive patients and median DRFS was 77.7 months. After initial treatment, further recurrences occurred in 68 (77.3%) patients, regardless the site of initial recurrence conclusions multimodal strategies are recommended to achieve better results when managing stage III melanoma patients after a positive SNB.


Assuntos
Melanoma , Neoplasias Cutâneas , Humanos , Melanoma/cirurgia , Melanoma/patologia , Estudos Retrospectivos , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/cirurgia , Neoplasias Cutâneas/patologia , Excisão de Linfonodo
2.
Crit Rev Food Sci Nutr ; 63(1): 18-32, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-34184959

RESUMO

Celiac disease (CD) is triggered by both genetic and environmental factors. More than 1% of the world's population is affected by CD. In recent years, studies have confirmed a worldwide rising trend in CD prevalence. "Westernized diet" is one of the main factors of this increasing prevalence. However, the relationship between wheat consumption, its dynamics, and CD has not been adequately investigated on a global scale. This study aimed to perform a multilevel analysis of the association between wheat consumption and CD. Wheat consumption data from countries and continents were obtained from the database. The relative increase/decrease in wheat consumption over a long period (since 1961) and a short period (since 2004) were calculated using various statistical tools. The relationship between wheat consumption and celiac frequency was determined using the R-commander R package version 2.6-2. Pearson's correlation coefficient (r = 0.88) confirmed a high positive correlation between wheat consumption and the prevalence of biopsy-proven CD by estimating continent-wide wheat consumption data, but an insignificant correlation was found when the data were compared country-wide.


Assuntos
Doença Celíaca , Humanos , Doença Celíaca/epidemiologia , Triticum , Prevalência , Análise Multinível , Dieta
3.
Int J Cancer ; 146(1): 181-191, 2020 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-31090066

RESUMO

Mechanisms of viral oncogenesis are diverse and include the off-target activity of enzymes expressed by the infected cells, which evolved to target viral genomes for controlling their infection. Among these enzymes, the single-strand DNA editing capability of APOBECs represent a well-conserved viral infection response that can also cause untoward mutations in the host DNA. Here we show, after evaluating somatic single-nucleotide variations and transcriptome data in 240 gastric cancer samples, a positive correlation between APOBEC3s mRNA-expression and the APOBEC-mutation signature, both increased in EBV+ tumors. The correlation was reinforced by the observation of APOBEC mutations preferentially occurring in the genomic loci of the most active transcripts. This EBV infection and APOBEC3 mutation-signature axis were confirmed in a validation cohort of 112 gastric cancer patients. Our findings suggest that APOBEC3 upregulation in EBV+ cancer may boost the mutation load, providing further clues to the mechanisms of EBV-induced gastric carcinogenesis. After further validation, this EBV-APOBEC axis may prove to be a secondary driving force in the mutational evolution of EBV+ gastric tumors, whose consequences in terms of prognosis and treatment implications should be vetted.


Assuntos
Citidina Desaminase/genética , DNA de Neoplasias/genética , Herpesvirus Humano 4/patogenicidade , Neoplasias Gástricas/virologia , Desaminases APOBEC , Carcinogênese , Genes Virais , Herpesvirus Humano 4/genética , Humanos , Mutação , Neoplasias Gástricas/patologia
4.
Nutrients ; 16(5)2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38474763

RESUMO

BACKGROUND: The Mediterranean diet is characterized by the predominance of the consumption of fruit, vegetables, cereals, nuts, and pulses; consumption of olive oil as the main source of fat; regular but moderate consumption of win; moderate consumption of fish, dairy products, eggs, and white meats; and low consumption of red meat as well as sugar and sugary products. In addition to the reported health benefits, the Mediterranean diet has also been widely recognized as a sustainable food pattern. The objective of this study was to understand the relationship between the degree of adherence to the Mediterranean diet of employees of the University of Porto and the relationship with the carbon footprint of their food consumption. METHODS: An observational, analytical study was carried out, through the analysis of food consumption data collected in the form of a survey in the previous 24 h inserted in the eAT24 software, as well as the analysis of sociodemographic, lifestyle, and health data collected in the questionnaire. The carbon footprint was calculated from the previous 24 h surveys using data available on a website, obtained in carbon dioxide equivalent per kilogram of food. Sociodemographic, eating habit, and lifestyle questions were selected to understand the relationship between these and adherence to the Mediterranean diet and the carbon footprint of food consumption. RESULTS: In total, 13.2% of the participants had a Mediterranean diet score equal to or greater than six, and the sample had an average food intake carbon footprint of 8146 ± 3081 CO2eq/Kg of food. A weak, statistically significant positive correlation (r = 0.142, p = 0.006) was observed between Mediterranean diet adherence and the carbon footprint of food intake. CONCLUSIONS: Most of the participants had a low adherence to the Mediterranean diet, as well as a high carbon footprint of food intake when compared to other countries. People with higher scores for Mediterranean diet adherence have, on average, a higher carbon footprint from food consumption intake.


Assuntos
Dieta Mediterrânea , Padrões Dietéticos , Humanos , Universidades , Portugal , Pegada de Carbono , Ingestão de Alimentos , Comportamento Alimentar
5.
Artigo em Inglês | MEDLINE | ID: mdl-38397615

RESUMO

Celiac disease (CD) is the chronic immune-mediated enteropathy of the small bowel, manifesting when exposure to gluten occurs in genetically predisposed individuals. Nowadays, the only treatment considered safe for CD is a gluten-free diet (GFD). However, one of the problems faced by celiac patients is the cross-contamination of gluten-free food when preparing meals, in addition to utensils, surfaces and equipment. This study aimed to evaluate cross-contamination in gluten-free products and strategies for removing gluten from cross-contamination in cooking environments. The selection of papers for this integrative review was carried out by searching different databases. Gluten cross-contamination is a global concern for celiac patients in food environments. Although some practices are positive, such as gluten labeling on processed food in several countries, it is crucial to promote good practices in food services around the world. Only a few studies showed effective results in removing gluten from surfaces and utensils; furthermore, sampling was limited, making it difficult to identify appropriate procedures to reduce cross-contamination. The variation in contamination in different kitchen environments also highlighted that celiac patients must continue paying attention to the methods used to prepare gluten-free food. More research is needed, especially into methods of removing gluten from surfaces and utensils, to ensure food safety for celiac patients in many food environments.


Assuntos
Doença Celíaca , Glutens , Humanos , Alimentos , Dieta Livre de Glúten , Intestino Delgado
6.
Nutrients ; 14(14)2022 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-35889901

RESUMO

Food labels are the first information tool used by consumers in the purchase and consumption of food products. Food labeling is a tool that can influence the consumers' perception of quality and, in turn, their food choice. This study characterizes and demonstrates the importance of labeling and the degree of consumers' perception and literacy about food labels through the application of an online questionnaire. The results obtained, in a sample of n = 467, showed that Portuguese consumers have the habit of reading the label and recognizing its importance but do not understand all the information contained in the label. They have an easier time understanding the front-of-pack labeling systems, especially those presented through symbols/colors. Thus, it demonstrates the need for greater education and literacy in the areas of food and nutrition so that through the reading and interpretation of labels, consumers can make informed food choices.


Assuntos
Comportamento de Escolha , Rotulagem de Alimentos , Comportamento do Consumidor , Rotulagem de Alimentos/métodos , Preferências Alimentares , Humanos , Valor Nutritivo , Percepção , Portugal
7.
Protein Pept Lett ; 29(1): 89-101, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34875984

RESUMO

BACKGROUND: The herbivores Danaus plexippus (Lepidoptera), Oncopeltus fasciatus, and Aphis nerii (Hemiptera) are special insects that feed on Calotropis procera (Apocynaceae) (Sodom Apple). At least 35 chemically distinct cardenolides have been reported in C. procera. OBJECTIVE: We aimed to evaluate the interaction between cardenolides and Na+/K+ ATPases from herbivores. METHODS: The Na+/K+ ATPases from these insects were modeled, and docking studies were performed involving cardenolides from C. procera. RESULTS: The replacement of serine in sensitive Na+/K+ ATPase by histidine, phenylalanine, and tyrosine in the structures examined suggested spatial impairment caused by interaction, probably making the herbivorous insects resistant against the cardenolides of C. procera. In addition, the ability of the insects to avoid cardenolide toxicity was not correlated with cardenolide polarity. Therefore, the plant fights predation through molecular diversity, and the insects, regardless of their taxonomy, face this molecular diversity through amino acid replacements at key positions of the enzyme targeted by the cardenolides. CONCLUSION: The results show the arsenal of chemically distinct cardenolides synthesized by the C. procera.


Assuntos
Apocynaceae , Calotropis , Calotropis/metabolismo , Cardenolídeos/química , Cardenolídeos/metabolismo , Cardenolídeos/farmacologia , Herbivoria , ATPase Trocadora de Sódio-Potássio/metabolismo
8.
Foods ; 10(4)2021 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-33805929

RESUMO

BACKGROUND: A wide variety of social, cultural and economic factors may influence dietary patterns. This work aims to identify the main determinants of food consumption and barriers for healthy eating at the workplace, in a university setting. METHODS: A cross-sectional observational study was conducted with 533 participants. Data were obtained through the application of a self-administered questionnaire that included socio-demographic information, food consumption determinants and the main perceived barriers for healthy eating at the workplace. RESULTS: The respondents identified "price" (22.5%), "meal quality" (20.7%), and "location/distance" (16.5%). For women, the determinant "availability of healthy food options" was more important than for men (p < 0.001). The food consumption determinants at the workplace most referred to by respondents were related to the nutritional value. Smell, taste, appearance and texture, and good value for money, were also considered important for choosing food at the workplace. Respondents referred to work commitments and lack of time as the main barriers for healthy eating at the workplace. CONCLUSIONS: Identification of determinants involved in food consumption, and the barriers for healthy eating, may contribute to a better definition of health promotion initiatives at the workplace aiming to improve nutritional intake.

9.
Sci Rep ; 11(1): 12565, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-34131209

RESUMO

Accurate designing of polymerase chain reaction (PCR) primers targeting conserved segments in viral genomes is desirable for preventing false-negative results and decreasing the need for standardization across different PCR protocols. In this work, we designed and described a set of primers and probes targeting conserved regions identified from a multiple sequence alignment of 2341 Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) genomes from the Global Initiative on Sharing All Influenza Data (GISAID). We subsequently validated those primers and probes in 211,833 SARS-CoV-2 whole-genome sequences. We obtained nine systems (forward primer + reverse primer + probe) that potentially anneal to highly conserved regions of the virus genome from these analyses. In silico predictions also demonstrated that those primers do not bind to nonspecific targets for human, bacterial, fungal, apicomplexan, and other Betacoronaviruses and less pathogenic sub-strains of coronavirus. The availability of these primer and probe sequences will make it possible to validate more efficient protocols for identifying SARS-CoV-2.


Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , Reação em Cadeia da Polimerase/métodos , SARS-CoV-2/genética , Simulação por Computador , Primers do DNA , Genoma Viral , Humanos , SARS-CoV-2/isolamento & purificação , Sequenciamento Completo do Genoma
10.
J Neuroimmunol ; 360: 577697, 2021 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-34461359

RESUMO

Zika virus (ZIKV) infection has been associated with the development of Neuromyelitis Optica Spectrum Disorder (NMOSD). ZIKV-induced antibodies that putatively cross-react to aquaporin-4 (AQP4) protein are suggested to cause inflammation of the optic nerve. A region of similarity between AQP4 and the ZIKV NS2B protein was identified. Our data showed that ZIKV-associated NMOSD patients develop anti-AQP4 antibodies, but not anti-ZIKV NS2B antibodies, revealing that cross-reacting antibodies are not the underlying cause of this phenotype. ZIKV infection in mice showed persistent viral replication in the eye tissue, suggesting that NMOSD symptoms are consequence of viral infection of the optic nerve cells.


Assuntos
Anticorpos Antivirais/imunologia , Aquaporina 4/imunologia , Autoanticorpos/imunologia , Neuromielite Óptica/imunologia , Zika virus/imunologia , Animais , Anticorpos Antivirais/sangue , Autoanticorpos/sangue , Reações Cruzadas , Epitopos/imunologia , Humanos , Imunoglobulina G/sangue , Imunoglobulina G/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Mimetismo Molecular , Neuromielite Óptica/etiologia , Nervo Óptico/virologia , Proteínas não Estruturais Virais/imunologia , Replicação Viral , Zika virus/fisiologia , Infecção por Zika virus/complicações , Infecção por Zika virus/imunologia , Infecção por Zika virus/virologia
11.
Front Immunol ; 11: 816, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32431712

RESUMO

In reverse vaccinology approaches, complete proteomes of bacteria are submitted to multiple computational prediction steps in order to filter proteins that are possible vaccine candidates. Most available tools perform such analysis only in a single strain, or a very limited number of strains. But the vast amount of genomic data had shown that most bacteria contain pangenomes, i.e., their genomic information contains core, conserved genes, and random accessory genes specific to each strain. Therefore, in reverse vaccinology methods it is of the utmost importance to define core proteins and core epitopes. EpitoCore is a decision-tree pipeline developed to fulfill that need. It provides surfaceome prediction of proteins from related strains, defines core proteins within those, calculate their immunogenicity, predicts epitopes for a given set of MHC alleles defined by the user, and then reports if epitopes are located extracellularly and if they are conserved among the core homologs. Pipeline performance is illustrated by mining peptide vaccine candidates in Mycobacterium avium hominissuis strains. From a total proteome of ~4,800 proteins per strain, EpitoCore predicted 103 highly immunogenic core homologs located at cell surface, many of those related to virulence and drug resistance. Conserved epitopes identified among these homologs allows the users to define sets of peptides with potential to immunize the largest coverage of tested HLA alleles using peptide-based vaccines. Therefore, EpitoCore is able to provide automated identification of conserved epitopes in bacterial pangenomic datasets.


Assuntos
Vacinas Bacterianas/imunologia , Epitopos/imunologia , Infecções por Mycobacterium/prevenção & controle , Mycobacterium/imunologia , Mycobacterium/patogenicidade , Proteoma/imunologia , Alelos , Antígenos de Bactérias/imunologia , Biologia Computacional/métodos , Genoma Bacteriano , Genômica/métodos , Antígenos de Histocompatibilidade Classe I/genética , Humanos , Mycobacterium/genética , Mycobacterium/metabolismo , Vacinas de Subunidades Antigênicas/imunologia , Vacinologia/métodos , Virulência/imunologia
12.
Virus Res ; 259: 1-9, 2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30339789

RESUMO

In recent years there has been a significant increase in the number of new species potentially belonging to the Totiviridae family. Most of these new viruses have not yet been covered by the Committee on Taxonomy of Viruses (ICTV) official classification. In this study, a phylogenetic analysis including new sequences of Totiviridae candidates revealed a clade including Giardiavirus and a great diversity of new totiviruses, which infect arthropods, protozoa and mollusc. This expanded Giardiavirus clade comprises two monophyletic groups, one of them including Giardia lamblia virus (GLV) grouped with viruses that infect arthropods and vertebrates (GLV-like group), and the other includes the previously proposed Artivirus group (IMNV-like group). A screening of the members of the GLV-like group in search of genomic elements already described in IMNV-like group revealed the existence of sites with a high propensity to become 2 A-like oligopeptides, mainly in a specific subgroup of arthropod viruses, suggesting that these viruses preserved ancestral characteristics. The existence of these "pseudo 2 A-sites" associated to phylogenetic reconstruction indicates that these sequences appear at a decisive stage for viral evolution. If they are changed to functional 2 A-like sequences, an irreversible route to increase the genome complexity will be initiated.


Assuntos
Evolução Molecular , Genoma Viral , Genômica , Oligonucleotídeos/genética , Totiviridae/classificação , Totiviridae/genética , Sequência de Aminoácidos , Biologia Computacional/métodos , Oligonucleotídeos/química , Filogenia , Análise de Sequência de DNA
13.
J Oncol ; 2019: 1217838, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30984261

RESUMO

BACKGROUND: Treatment of advanced uterine cervical cancer has advanced little in the last 15 years. Although two phase III trials showed survival benefit with the addition of consolidation chemotherapy (CT) after cisplatin-based chemoradiotherapy (RTCT), it is not considered standard of care. We aimed to evaluate the benefit of consolidation CT compared to no additional treatment in patients treated with RTCT. METHODS: This is a retrospective study including 186 patients with FIGO stage IB2, IIA2, or IIB to IVB (paraaortic lymph nodes only) uterine cervical cancer who were treated with standard RTCT alone or RTCT followed by consolidation CT. Overall survival (OS), progression free survival (PFS), and the risk of distant and local relapses were compared between the two treatment groups. RESULTS: At 3 years OS was 91% versus 82.3% (p=0.027), PFS 84.3% versus 54.4% (p=0.047), and distant metastasis free survival (DMFS) 80.4% versus 62.5% (p=0.027) in favor of the consolidation CT group. Multivariate analysis confirmed the benefit of consolidation CT. There was no difference in locoregional free survival (LRFS). Positive lymph node was related to a higher risk of distant relapse. In the lymph node positive subgroup consolidation CT resulted in longer OS (p=0.050), PFS (p=0.014), and DMFS (p=0.022); in the lymph node negative subgroup there was no benefit from consolidation CT. CONCLUSIONS: Use of consolidation CT resulted in longer OS and PFS, mostly due to control of distant relapses. Patients at higher risk of distant relapse showed the greatest benefit. This data generates a hypothesis that could help to better select patients to consolidation CT.

14.
Lung Cancer ; 124: 248-254, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30268469

RESUMO

BACKGROUND: Anti-PD-1 immunotherapy has dramatically shifted therapeutic perspectives for advanced non-small cell lung cancer (NSCLC). We assessed cost-effectiveness of anti-PD-1 antibody pembrolizumab compared to platinum-doublet chemotherapy as first-line therapy for advanced NSCLC. METHODS: We retrieved survival, progression, and safety data comparing first-line pembrolizumab to platinum-doublets for advanced NSCLC patients with PD-L1 expression ≥50%, non-mutated EGFR, and non-translocated ALK, from KEYNOTE-024. Published United Kingdom (UK) and United States (US) costs informed incremental cost-effectiveness ratios (ICERs). Our analysis was based on a Bayesian Markov model of disease with full lifetime horizon. We estimated costs in USD and summarized effectiveness as quality-adjusted life-years (QALYs). RESULTS: Patients treated with pembrolizumab accumulated 1.80 QALYs (95% CrI 1.56-1.89), for moderate dependency between outcomes, compared to 1.06 QALYs (0.94-1.13) with chemotherapy. From a British National Health System (NHS) perspective, the ICER was $52k ($43k-$69k) per end-of-life (EoL) adjusted QALY gained, above the 42k USD threshold, while from a US cost perspective, the ICER was $49k ($40k-67k) per EoL adjusted QALY, below the hypothetical 100k USD threshold. CONCLUSIONS: Evidence suggests first-line pembrolizumab for NSCLC may be cost-effective in the US but not the UK, in spite of very similar ICER values in both countries.


Assuntos
Anticorpos Monoclonais Humanizados/uso terapêutico , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Imunoterapia/métodos , Neoplasias Pulmonares/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/economia , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Análise Custo-Benefício , Medicina Baseada em Evidências , Humanos , Neoplasias Pulmonares/economia , Neoplasias Pulmonares/mortalidade , Estadiamento de Neoplasias , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Anos de Vida Ajustados por Qualidade de Vida , Análise de Sobrevida , Reino Unido , Estados Unidos
15.
Oncol Lett ; 13(6): 4641-4650, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28599464

RESUMO

The role of base excision repair (BER) genes in Philadelphia-negative (PN)-myeloproliferative neoplasms (MPNs) susceptibility was evaluated by genotyping eight polymorphisms [apurinic/apyrimidinic endodeoxyribonuclease 1, mutY DNA glycosylase, earlier mutY homolog (E. coli) (MUTYH), 8-oxoguanine DNA glycosylase 1, poly (ADP-ribose) polymerase (PARP) 1, PARP4 and X-ray repair cross-complementing 1 (XRCC1)] in a case-control study involving 133 Caucasian Portuguese patients. The results did not reveal a correlation between individual BER polymorphisms and PN-MPNs when considered as a whole. However, stratification for essential thrombocythaemia revealed i) borderline effect/tendency to increased risk when carrying at least one variant allele for XRCC1_399 single-nucleotide polymorphism (SNP); ii) decreased risk for Janus kinase 2-positive patients carrying at least one variant allele for XRCC1_399 SNP; and iii) decreased risk in females carrying at least one variant allele for MUTYH SNP. Combination of alleles demonstrated an increased risk to PN-MPNs for one specific haplogroup. These findings may provide evidence for gene variants in susceptibility to MPNs. Indeed, common variants in DNA repair genes may hamper the capacity to repair DNA, thus increasing cancer susceptibility.

16.
Food Res Int ; 100(Pt 1): 566-571, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28873722

RESUMO

Only some of ingested nutrients are available for absorption by the organism. The foods generally are submitted to some heat processing that may interfere in the bioaccessibility of nutrients. There are no studies of the influence of cooking under vacuum (sous vide) on the bioaccessibility of minerals. This study evaluated the in vitro bioaccessibility of Ca, Cu, Fe, K, Mg and Zn in bovine liver samples after traditional cooking in water and using the sous vide procedure. All heat treatments of bovine liver promoted the increase of the bioaccessibility of Ca, Cu, Fe, K and Mg, except for Zn when the effect was the opposite. The sous vide method provided higher bioaccessibility of these minerals than cooking in boiling water, except for K when both methods presented equivalent values. Samples of raw liver and liver cooked using sous vide method presented the following percentage of bioaccessible fraction, respectively: 39.7% and 95.8% (Ca), 8.78% and 26.9% (Cu), 8.80% and 39.5% (Fe), 30.2% and 42.6% (K), 26.4% and 43.9% (Mg), 24.8% and 36.3% (Zn). Thus, under the aspect of improvement availability of studied minerals by organism, the sous-vide technique was the most suitable to cook bovine liver.


Assuntos
Culinária/métodos , Fígado/química , Carne/análise , Metais/análise , Oligoelementos/análise , Animais , Disponibilidade Biológica , Bovinos , Digestão , Temperatura Alta , Metais/química , Modelos Biológicos , Oligoelementos/química , Vácuo
17.
Peptides ; 94: 91-98, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28552408

RESUMO

Anionic Peptides are molecules rich in aspartic acid (Asp) and/or glutamic acid (Glu) residues in the primary structure. This work presents, for the first time, structural characterization and biological activity assays of an anionic peptide from the venom of the scorpion Tityus stigmurus, named TanP. The three-dimensional structure of TanP was obtained by computational modeling and refined by molecular dynamic (MD) simulations. Furthermore, we have performed circular dichroism (CD) analysis to predict TanP secondary structure, and UV-vis spectroscopy to evaluate its chelating activity. CD indicated predominance of random coil conformation in aqueous medium, as well as changes in structure depending on pH and temperature. TanP has chelating activity on copper ions, which modified the peptide's secondary structure. These results were corroborated by MD data. The molar ratio of binding (TanP:copper) depends on the concentration of peptide: at lower TanP concentration, the molar ratio was 1:5 (TanP:Cu2+), whereas in concentrated TanP solution, the molar ratio was 1:3 (TanP:Cu2+). TanP was not cytotoxic to non-neoplastic or cancer cell lines, and showed an ability to inhibit the in vitro release of nitric oxide by LPS-stimulated macrophages. Altogether, the results suggest TanP is a promising peptide for therapeutic application as a chelating agent.


Assuntos
Quelantes/química , Cobre/química , Peptídeos/química , Escorpiões/metabolismo , Sequência de Aminoácidos , Animais , Linhagem Celular , Dicroísmo Circular , Camundongos , Simulação de Dinâmica Molecular , Peptídeos/metabolismo , Estrutura Secundária de Proteína , Venenos de Escorpião/química , Venenos de Escorpião/metabolismo , Alinhamento de Sequência
18.
Mar Biotechnol (NY) ; 17(2): 211-8, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25634054

RESUMO

A screening was performed using nine marine-derived fungi as biocatalysts and the natural products (-)-ambrox® (1), (-)-sclareol (2), and (+)-sclareolide (3) in order to select the microorganisms able to catalyze the biooxidation of these compounds. It was observed that only the Aspergillus sydowii CBMAI 934, Botryosphaeria sp., Eutypella sp., and Xylaria sp. presented active oxidoreductases and catalyzed the regioselective hydroxylation in the natural products. The hydroxylated metabolites obtained were 1ß-hydroxy-ambrox (1a) (14%, A. sydowii CBMAI 934); 3ß-hydroxy-ambrox (1b) (17%, Botryosphaeria sp.; 11%, Eutypella sp.); 3ß-hydroxy-sclareol (2a) (31%, Xylaria sp.; 69%, Botryosphaeria sp.; 55%, Eutypella sp.); 18-hydroxy-sclareol (2b) (10%, Xylaria sp.); and 3ß-hydroxy-sclareolide (3a) (34%, Botryosphaeria sp.; 7%, Eutypella sp.). This is the first report of biohydroxylation of (-)-ambrox® (1), (-)-sclareol (2), and (+)-sclareolide (3) by whole mycelia of marine-derived fungi.


Assuntos
Aspergillus/metabolismo , Produtos Biológicos/metabolismo , Diterpenos/metabolismo , Furanos/metabolismo , Naftalenos/metabolismo , Penicillium/metabolismo , Poríferos/microbiologia , Animais , Oceano Atlântico , Biotransformação , Brasil , Catálise , Diterpenos/química , Furanos/química , Hidroxilação , Estrutura Molecular , Naftalenos/química , Oxirredução
19.
PLoS One ; 10(3): e0119871, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25789746

RESUMO

Mo-CBP3 is a chitin-binding protein from M. oleifera seeds that inhibits the germination and mycelial growth of phytopathogenic fungi. This protein is highly thermostable and resistant to pH changes, and therefore may be useful in the development of new antifungal drugs. However, the relationship of MoCBP3 with the known families of carbohydrate-binding domains has not been established. In the present study, full-length cDNAs encoding 4 isoforms of Mo-CBP3 (Mo-CBP3-1, Mo-CBP3-2, Mo-CBP3-3 and Mo-CBP3-4) were cloned from developing seeds. The polypeptides encoded by the Mo-CBP3 cDNAs were predicted to contain 160 (Mo-CBP3-3) and 163 amino acid residues (Mo-CBP3-1, Mo-CBP3-2 and Mo-CBP3-4) with a signal peptide of 20-residues at the N-terminal region. A comparative analysis of the deduced amino acid sequences revealed that Mo-CBP3 is a typical member of the 2S albumin family, as shown by the presence of an eight-cysteine motif, which is a characteristic feature of the prolamin superfamily. Furthermore, mass spectrometry analysis demonstrated that Mo-CBP3 is a mixture of isoforms that correspond to different mRNA products. The identification of Mo-CBP3 as a genuine member of the 2S albumin family reinforces the hypothesis that these seed storage proteins are involved in plant defense. Moreover, the chitin-binding ability of Mo-CBP3 reveals a novel functionality for a typical 2S albumin.


Assuntos
Albuminas 2S de Plantas/genética , Proteínas de Transporte/genética , Quitinases/genética , Moringa oleifera/genética , Proteínas de Plantas/genética , Albuminas 2S de Plantas/metabolismo , Sequência de Aminoácidos , Proteínas de Transporte/metabolismo , Quitina/genética , Quitina/metabolismo , Quitinases/classificação , Sementes/química , Sementes/genética
20.
Phytochemistry ; 65(1): 59-69, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14697271

RESUMO

The complete sequences of nuclear ribosomal DNA (nrDNA) internal transcribed spacer regions (ITS/5.8S) were determined for species belonging to six genera from the subtribe Diocleinae as well as for the anomalous genera Calopogonium and Pachyrhizus. Phylogenetic trees constructed by distance matrix, maximum parsimony and maximum likelihood methods showed that Calopogonium and Pachyrhizus were outside the clade Diocleinae (Canavalia, Camptosema, Cratylia, Dioclea, Cymbosema, and Galactia). This finding supports previous morphological, phytochemical, and molecular evidence that Calopogonium and Pachyrhizus do not belong to the subtribe Diocleinae. Within the true Diocleinae clade, the clustering of genera and species were congruent with morphology-based classifications, suggesting that ITS/5.8S sequences can provide enough informative sites to allow resolution below the genus level. This is the first evidence of the phylogeny of subtribe Diocleinae based on nuclear DNA sequences.


Assuntos
DNA Ribossômico/genética , Fabaceae/genética , Algoritmos , Sequência de Bases , Núcleo Celular/genética , Sequência Consenso , DNA de Plantas/genética , Fabaceae/classificação , Dados de Sequência Molecular , Filogenia , Alinhamento de Sequência , Homologia de Sequência do Ácido Nucleico , Transcrição Gênica
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