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1.
Artículo en Inglés | MEDLINE | ID: mdl-38397615

RESUMEN

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.


Asunto(s)
Enfermedad Celíaca , Glútenes , Humanos , Alimentos , Dieta Sin Gluten , Intestino Delgado
2.
Cancer Invest ; 41(10): 830-836, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37962565

RESUMEN

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.


Asunto(s)
Melanoma , Neoplasias Cutáneas , Humanos , Melanoma/cirugía , Melanoma/patología , Estudios Retrospectivos , Biopsia del Ganglio Linfático Centinela , Neoplasias Cutáneas/cirugía , Neoplasias Cutáneas/patología , Escisión del Ganglio Linfático
3.
Protein Pept Lett ; 29(1): 89-101, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34875984

RESUMEN

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.


Asunto(s)
Apocynaceae , Calotropis , Calotropis/metabolismo , Cardenólidos/química , Cardenólidos/metabolismo , Cardenólidos/farmacología , Herbivoria , ATPasa Intercambiadora de Sodio-Potasio/metabolismo
4.
J Neuroimmunol ; 360: 577697, 2021 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-34461359

RESUMEN

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.


Asunto(s)
Anticuerpos Antivirales/inmunología , Acuaporina 4/inmunología , Autoanticuerpos/inmunología , Neuromielitis Óptica/inmunología , Virus Zika/inmunología , Animales , Anticuerpos Antivirales/sangre , Autoanticuerpos/sangre , Reacciones Cruzadas , Epítopos/inmunología , Humanos , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Ratones , Ratones Endogámicos C57BL , Imitación Molecular , Neuromielitis Óptica/etiología , Nervio Óptico/virología , Proteínas no Estructurales Virales/inmunología , Replicación Viral , Virus Zika/fisiología , Infección por el Virus Zika/complicaciones , Infección por el Virus Zika/inmunología , Infección por el Virus Zika/virología
5.
Sci Rep ; 11(1): 12565, 2021 06 15.
Artículo en Inglés | MEDLINE | ID: mdl-34131209

RESUMEN

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.


Asunto(s)
Prueba de Ácido Nucleico para COVID-19/métodos , Reacción en Cadena de la Polimerasa/métodos , SARS-CoV-2/genética , Simulación por Computador , Cartilla de ADN , Genoma Viral , Humanos , SARS-CoV-2/aislamiento & purificación , Secuenciación Completa del Genoma
6.
Front Immunol ; 11: 816, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32431712

RESUMEN

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.


Asunto(s)
Vacunas Bacterianas/inmunología , Epítopos/inmunología , Infecciones por Mycobacterium/prevención & control , Mycobacterium/inmunología , Mycobacterium/patogenicidad , Proteoma/inmunología , Alelos , Antígenos Bacterianos/inmunología , Biología Computacional/métodos , Genoma Bacteriano , Genómica/métodos , Antígenos de Histocompatibilidad Clase I/genética , Humanos , Mycobacterium/genética , Mycobacterium/metabolismo , Vacunas de Subunidad/inmunología , Vacunología/métodos , Virulencia/inmunología
7.
Int J Cancer ; 146(1): 181-191, 2020 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-31090066

RESUMEN

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.


Asunto(s)
Citidina Desaminasa/genética , ADN de Neoplasias/genética , Herpesvirus Humano 4/patogenicidad , Neoplasias Gástricas/virología , Desaminasas APOBEC , Carcinogénesis , Genes Virales , Herpesvirus Humano 4/genética , Humanos , Mutación , Neoplasias Gástricas/patología
8.
J Oncol ; 2019: 1217838, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30984261

RESUMEN

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.

9.
Virus Res ; 259: 1-9, 2019 01 02.
Artículo en Inglés | MEDLINE | ID: mdl-30339789

RESUMEN

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.


Asunto(s)
Evolución Molecular , Genoma Viral , Genómica , Oligonucleótidos/genética , Totiviridae/clasificación , Totiviridae/genética , Secuencia de Aminoácidos , Biología Computacional/métodos , Oligonucleótidos/química , Filogenia , Análisis de Secuencia de ADN
10.
Food Res Int ; 100(Pt 1): 566-571, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28873722

RESUMEN

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.


Asunto(s)
Culinaria/métodos , Hígado/química , Carne/análisis , Metales/análisis , Oligoelementos/análisis , Animales , Disponibilidad Biológica , Bovinos , Digestión , Calor , Metales/química , Modelos Biológicos , Oligoelementos/química , Vacio
11.
Peptides ; 94: 91-98, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28552408

RESUMEN

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.


Asunto(s)
Quelantes/química , Cobre/química , Péptidos/química , Escorpiones/metabolismo , Secuencia de Aminoácidos , Animales , Línea Celular , Dicroismo Circular , Ratones , Simulación de Dinámica Molecular , Péptidos/metabolismo , Estructura Secundaria de Proteína , Venenos de Escorpión/química , Venenos de Escorpión/metabolismo , Alineación de Secuencia
12.
PLoS One ; 10(3): e0119871, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25789746

RESUMEN

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.


Asunto(s)
Albuminas 2S de Plantas/genética , Proteínas Portadoras/genética , Quitinasas/genética , Moringa oleifera/genética , Proteínas de Plantas/genética , Albuminas 2S de Plantas/metabolismo , Secuencia de Aminoácidos , Proteínas Portadoras/metabolismo , Quitina/genética , Quitina/metabolismo , Quitinasas/clasificación , Semillas/química , Semillas/genética
13.
Mar Biotechnol (NY) ; 17(2): 211-8, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25634054

RESUMEN

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.


Asunto(s)
Aspergillus/metabolismo , Productos Biológicos/metabolismo , Diterpenos/metabolismo , Furanos/metabolismo , Naftalenos/metabolismo , Penicillium/metabolismo , Poríferos/microbiología , Animales , Océano Atlántico , Biotransformación , Brasil , Catálisis , Diterpenos/química , Furanos/química , Hidroxilación , Estructura Molecular , Naftalenos/química , Oxidación-Reducción
14.
Phytochemistry ; 65(1): 59-69, 2004 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-14697271

RESUMEN

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.


Asunto(s)
ADN Ribosómico/genética , Fabaceae/genética , Algoritmos , Secuencia de Bases , Núcleo Celular/genética , Secuencia de Consenso , ADN de Plantas/genética , Fabaceae/clasificación , Datos de Secuencia Molecular , Filogenia , Alineación de Secuencia , Homología de Secuencia de Ácido Nucleico , Transcripción Genética
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