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1.
JCO Glob Oncol ; 10: e2300011, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38237094

RESUMEN

PURPOSE: Multidisciplinary molecular tumor boards (MTBs) decode complex genomic data into clinical recommendations. Although MTBs are well-established in the oncology practice in developed countries, this strategy needs to be better explored in developing countries. Herein, we describe the possible benefits and limitations of the first MTB established in Colombia. METHODS: Demographic, clinical, and genomic information was collected between August 2020 and November 2021. By mid-2020, an MTB strategy was created to discuss clinical cases with one or more genomic alterations identified by next-generation sequencing using an open-access virtual platform. We characterized the patient population as benefiting from the recommended treatment option. We assessed the benefits and access to available targeted therapies that have the potential to change clinical management by making recommendations to treating oncologists on the basis of genomic profiling. However, we did not assess the treatment oncologists' compliance with MTB recommendations because they were not intended to replace clinical judgment/standard of care. RESULTS: A total of 146 patients were included in the discussions of the MTB. The median age was 59 years, and 59.6% were women. Genomic results prompting a change in therapeutic decisions were obtained in 53.1% of patients (95% CI, 44.9 to 61.3). The most prevalent malignancy was non-small-cell lung cancer (51%). Other malignancies represented 60%, 50%, and 30% of patients with soft-tissue sarcomas, brain tumors, and breast cancer, respectively. CONCLUSION: Using an open-access virtual platform, MTBs were feasible in low- and middle-income countries on the basis of the capability to provide the benefits and access to available targeted therapies that are not standard of care. Furthermore, MTB recommendations were made available to the treating oncologist in different locations across Colombia, providing the option to modify clinical management in most of these patients.


Asunto(s)
Hispánicos o Latinos , Neoplasias , Evaluación de Resultado en la Atención de Salud , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Mama , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Oncología Médica , Sarcoma , Neoplasias Encefálicas , Neoplasias de los Tejidos Blandos , Neoplasias/terapia , Resultado del Tratamiento
2.
Vet Parasitol ; 326: 110081, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38113611

RESUMEN

B. bovis invasion of bovine erythrocytes requires tight junction formation involving AMA-1/RON2 complex interaction. RON2 has been considered a vaccine candidate since antibodies targeting the protein can inhibit parasite invasion of target cells; however, the mechanism controlling B. bovis RON2 interaction with red blood cells is not yet fully understood. This study was thus aimed at identifying B. bovis RON2 protein regions associated with interaction with bovine erythrocytes. Natural selection analysis of the ron2 gene identified predominantly negative selection signals in the C-terminal region. Interestingly, protein-cell and competition assays highlighted the RON2-C region's role in peptide 42918-mediated erythrocyte binding, probably to a sialoglycoprotein receptor. This peptide (1218SFIMVKPPALHCVLKPVETL1237) lies within an intrinsically disordered region of the RON2 secondary structure flanked by two helical residues. The study provides, for the first time, valuable insights into RON2's role in interaction with its target cells. Future studies are required for studying the peptide's potential as an anti-B. bovis vaccine component.


Asunto(s)
Babesia bovis , Vacunas , Animales , Bovinos , Epítopos , Proteínas Protozoarias/metabolismo , Péptidos , Eritrocitos/parasitología
3.
Neurooncol Pract ; 10(4): 381-390, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37457227

RESUMEN

Background: DICER1 alterations are associated with intracranial tumors in the pediatric population, including pineoblastoma, pituitary blastoma, and the recently described "primary DICER1-associated CNS sarcoma" (DCS). DCS is an extremely aggressive tumor with a distinct methylation signature and a high frequency of co-occurring mutations. However, little is known about its treatment approach and the genomic changes occurring after exposure to chemoradiotherapy. Methods: We collected clinical, histological, and molecular data from eight young adults with DCS. Genomic analysis was performed by Next-generation Sequencing (NGS). Subsequently, an additional germline variants analysis was completed. In addition, an NGS analysis on post-progression tumor tissue or liquid biopsy was performed when available. Multiple clinicopathological characteristics, treatment variables, and survival outcomes were assessed. Results: Median age was 20 years. Most lesions were supratentorial. Histology was classified as fusiform cell sarcomas (50%), undifferentiated (unclassified) sarcoma (37.5%), and chondrosarcoma (12.5%). Germline pathogenic DICER1 variants were present in two patients, 75% of cases had more than one somatic alteration in DICER1, and the most frequent commutation was TP53. Seven patients were treated with surgery, Ifosfamide, Cisplatin, and Etoposide (ICE) chemotherapy and radiotherapy. The objective response was 75%, and the median time to progression (TTP) was 14.5 months. At progression, the most common mutations were in KRAS and NF1. Overall survival was 30.8 months. Conclusions: DCS is an aggressive tumor with limited therapeutic options that requires a comprehensive diagnostic approach, including molecular characterization. Most cases had mutations in TP53, NF1, and PTEN, and most alterations at progression were related to MAPK, RAS and PI3K signaling pathways.

4.
Hum Immunol ; 84(9): 484-491, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37380553

RESUMEN

NRAMP1 and VDR gene polymorphisms have been variably associated with susceptibility to tuberculosis (TB) amongst populations having different genetic background. NRAMP1 and VDR gene variants' association with susceptibility to active infection by Mycobacterium tuberculosis (Mtb) was analyzed in the Warao Amerindian population, an ethnic population from Venezuela's Orinoco delta region. Genomic DNA was extracted from individuals with and without TB to evaluate genetic polymorphism by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Four NRAMP1 gene polymorphisms were analyzed: D543N (rs17235409), 3' UTR (rs17235416), INT4 (rs3731865), and 274C/T (rs2276631), and one VDR gene polymorphism: FokI (rs2228570). The results showed that the genotypes D543N-A/A, 3'UTR-TGTG+/+, INT4-C/C, and 274C/T-T/T of known polymorphism in the NRAMP1 gene, as well as the genotypes FokI-F/f and FokI-f/f in the VDR gene were most often found in indigenous Warao with active TB. Binomial logistic regression was used for evaluating associations between polymorphisms and risk of contracting TB, an association between NRAMP1-D543N-A/A genotype distribution and TB susceptibility was found in Warao Amerindians. Regarding Venezuelan populations having different genetic backgrounds; statistically significant TB associations concerning NRAMP1-D543N-A/A, INT4-C/C and 3'UTR-TGTG+/+ variant genotype distributions in Warao Amerindians (indigenous) compared to Creole (admixed non-indigenous population) individuals were found. In conclusion, the results thus indicated that the association between NRAMP1-D543N-A/A genotype and TB in Warao Amerindians could support such allele's role in host susceptibility to Mtb infection.


Asunto(s)
Proteínas de Transporte de Catión , Tuberculosis , Humanos , Regiones no Traducidas 3'/genética , Venezuela , Predisposición Genética a la Enfermedad , Proteínas de Transporte de Catión/genética , Tuberculosis/genética , Genotipo , Estudios de Casos y Controles
5.
Target Oncol ; 18(3): 425-440, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-37017806

RESUMEN

BACKGROUND: Epidermal growth factor receptor (EGFR) mutations (EGFRm) represent one of the most common genomic alterations identified among patients with non-small cell lung cancer (NSCLC). Several targeted agents for patients with EGFRm have been proven safe and effective, including the third-generation tyrosine kinase inhibitor (TKI) osimertinib. Nonetheless, some patients will present with or develop EGFR-TKI resistance mechanisms. OBJECTIVE: We characterized the genomic landscape of primary resistance to osimertinib among Hispanic patients with EGFR-mutant NSCLC. METHODS: An observational longitudinal cohort study was conducted with two groups of patients, those with intrinsic resistance (cohort A) and those with long-term survival (cohort B). All patients were treated and followed between January 2018 and May 2022. All patients were assessed for Programmed Cell Death Ligand 1 (PD-L1) expression and Bcl-2-like protein 11 (BIM)/AXL mRNA expression before starting TKI. After 8 weeks of treatment, a liquid biopsy was performed to determine the presence of circulating free DNA (cfDNA), and next-generation sequencing (NGS) was used to identify mutations at the time of progression. In both cohorts, overall response rate (ORR), progression-free survival (PFS), and overall survival (OS) were evaluated. RESULTS: We found a homogeneous distribution of EGFR-sensitizing mutations in both cohorts. For cohort A, exon 21 mutations were more common than exon 19 deletions (ex19dels) for cohort B (P = 0.0001). The reported ORR for osimertinib was 6.3% and 100% for cohorts A and B, respectively (P = 0.0001). PFS was significantly higher in cohort B (27.4 months vs. 3.1 months; P = 0.0001) and ex19del patients versus L858R (24.5 months, 95% confidence interval [CI] 18.2-NR), vs. 7.6 months, 95% CI 4.8-21.1; P = 0.001). OS was considerably lower for cohort A (20.1 months vs. 36.0 months; P = 0.0001) and was better for patients with ex19del, no brain metastasis, and low tumor mutation burden. At the time of progression, more mutations were found in cohort A, identifying off-target alterations more frequently, including TP53, RAS, and RB1. CONCLUSION: EGFR-independent alterations are common among patients with primary resistance to osimertinib and significantly impact PFS and OS. Our results suggest that among Hispanic patients, other variables associated with intrinsic resistance include the number of commutations, high levels AXL mRNA, and low levels of BIM mRNA, T790M de novo, EGFR p.L858R presence, and a high tumoral mutational burden.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Ácidos Nucleicos Libres de Células , Neoplasias Pulmonares , Humanos , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Estudios Longitudinales , Receptores ErbB/genética , Receptores ErbB/metabolismo , Mutación , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Compuestos de Anilina/farmacología , Compuestos de Anilina/uso terapéutico , Estudios de Cohortes , Genómica , Hispánicos o Latinos
6.
Int J Mol Sci ; 24(6)2023 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-36982294

RESUMEN

Bovine babesiosis is caused by the Apicomplexa parasites from the genus Babesia. It is one of the most important tick-borne veterinary diseases worldwide; Babesia bovis being the species associated with the most severe clinical signs of the disease and causing the greatest economic losses. Many limitations related to chemoprophylaxis and the acaricides control of transmitting vectors have led to the adoption of live attenuated vaccine immunisation against B. bovis as an alternative control strategy. However, whilst this strategy has been effective, several drawbacks related to its production have prompted research into alternative methodologies for producing vaccines. Classical approaches for developing anti-B. bovis vaccines are thus discussed in this review and are compared to a recent functional approach to highlight the latter's advantages when designing an effective synthetic vaccine targeting this parasite.


Asunto(s)
Babesia bovis , Babesia , Enfermedades de los Bovinos , Enfermedades por Picaduras de Garrapatas , Animales , Bovinos , Vacunas Atenuadas , Vacunas Sintéticas
7.
Vet Parasitol ; 312: 109834, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36343530

RESUMEN

Merozoite surface antigen-1 is a glycoprotein expressed by Babesia bovis and is considered a vaccine candidate given that antibodies against it are able to partially block in vitro invasion of bovine erythrocytes. Despite this, no study to date has confirmed the target cell binding properties of the full MSA-1 or its fragments. This research has thus been focused on identifying protein regions playing a role in erythrocyte attachment, based on genetic diversity and natural selection analysis. Two regions under functional constraint (nucleotides 134-428 and 464-629) having a preponderance of negatively-selected signals were identified in silico. Three non-overlapping peptides derived from functionally constraint regions (42422 (39PEGSFYDDMSKFYGAVGSFD58), 42424 (91NALIKNNPMIRPDLFNATIV110) and 42426 (150TDIVEEDREKAVEYFKKHVY169)) were able to specifically bind to a sialoglycoprotein located on the bovine erythrocyte surface as confirmed by sensitive and specific peptide-cell interaction competition assays using both enzymatically treated and untreated red blood cells. Interestingly, it was predicted that peptides 42422 and 42426 have a helical structure and conserved motifs in all strain/isolates. These findings provide evidence, for the first time, related to B. bovis MSA-1 short regions used by the parasite in erythrocyte binding which could be predicted using natural selection analysis. Future work focused on evaluating these peptides' antigenic ability during natural infection, and their ability to induce protection in immunisation assays are needed to confirm their usefulness as synthetic vaccine candidates.


Asunto(s)
Babesia bovis , Babesiosis , Enfermedades de los Bovinos , Bovinos , Animales , Babesia bovis/genética , Proteína 1 de Superficie de Merozoito/genética , Antígenos de Protozoos , Eritrocitos/parasitología , Enfermedades de los Bovinos/parasitología , Babesiosis/parasitología , Proteínas Protozoarias
8.
Comput Intell Neurosci ; 2022: 6872045, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35990113

RESUMEN

Image segmentation and computer vision are becoming more important in computer-aided design. A computer algorithm extracts image borders, colours, and textures. It also depletes resources. Technical knowledge is required to extract information about distinctive features. There is currently no medical picture segmentation or recognition software available. The proposed model has 13 layers and uses dilated convolution and max-pooling to extract small features. Ghost model deletes the duplicated features, makes the process easier, and reduces the complexity. The Convolution Neural Network (CNN) generates a feature vector map and improves the accuracy of area or bounding box proposals. Restructuring is required for healing. As a result, convolutional neural networks segment medical images. It is possible to acquire the beginning region of a segmented medical image. The proposed model gives better results as compared to the traditional models, it gives an accuracy of 96.05, Precision 98.2, and recall 95.78. The first findings are improved by thickening and categorising the image's pixels. Morphological techniques may be used to segment medical images. Experiments demonstrate that the recommended segmentation strategy is effective. This study rethinks medical image segmentation methods.


Asunto(s)
Aprendizaje Profundo , Procesamiento de Imagen Asistido por Computador , Algoritmos , Procesamiento de Imagen Asistido por Computador/métodos , Redes Neurales de la Computación , Programas Informáticos
9.
Front Vet Sci ; 8: 732129, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34504891

RESUMEN

Blastocystis is frequently reported in fecal samples from animals and humans worldwide, and a variety of subtypes (STs) have been observed in wild and domestic animals. In Colombia, few studies have focused on the transmission dynamics and epidemiological importance of Blastocystis in animals. In this study, we characterized the frequency and subtypes of Blastocystis in fecal samples of domestic animals including pigs, minipigs, cows, dogs, horses, goats, sheep, and llama from three departments of Colombia. Of the 118 fecal samples included in this study 81.4% (n = 96) were positive for Blastocystis using a PCR that amplifies a fragment of the small subunit ribosomal RNA (SSU rRNA) gene. PCR positive samples were sequenced by next generation amplicon sequencing (NGS) to determine subtypes. Eleven subtypes were detected, ten previously reported, ST5 (50.7%), ST10 (47.8%), ST25 (34.3%), ST26 (29.8%), ST21 (22.4%), ST23 (22.4%), ST1 (17.9%), ST14 (16.4%), ST24 (14.9%), ST3 (7.5%), and a novel subtype, named ST32 (3.0%). Mixed infection and/or intra -subtype variations were identified in most of the samples. Novel ST32 was observed in two samples from a goat and a cow. To support novel subtype designation, a MinION based sequencing strategy was used to generate the full-length of the SSU rRNA gene. Comparison of full-length nucleotide sequences with those from current valid subtypes supported the designation of ST32. This is the first study in Colombia using NGS to molecularly characterize subtypes of Blastocystis in farm animals. A great diversity of subtypes was observed in domestic animals including subtypes previously identified in humans. Additionally, subtype overlap between the different hosts examined in this study were observed. These findings highlight the presence of Blastocystis subtypes with zoonotic potential in farm animals indicating that farm animals could play a role in transmission to humans.

10.
Parasit Vectors ; 14(1): 424, 2021 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-34425895

RESUMEN

BACKGROUND: There has been a long-standing debate over the taxonomic status of Rhipicephalus sanguineus sensu lato. Different studies worldwide have reported the occurrence of different well-defined lineages, in addition to Rhipicephalus sanguineus sensu stricto. To date, there are very few studies examining the diverse aspects of this tick in Colombia. We assessed the population structure and genetic diversity of R. sanguineus s.l. in eight departmental regions across Colombia. METHODS: A total of 170 ticks were collected from dogs in different departments of Colombia. All specimens were morphologically compatible with R. sanguineus s.l. and subjected to genetic analysis. DNA sequences were obtained for the 12S rDNA, cytochrome oxidase I (COI) and internal transcribed spacer 2 (ITS2) markers. A concatenated set of all mitochondrial markers was also constructed. Next, maximum likelihood phylogenetic trees were constructed using the sequences generated herein and sequences available in GenBank. Finally, we assessed different summary statistics and analysed population structure and divergence with Fst and Dxy and demographic changes with Tajima's D and Fu and Li's statistical tests. RESULTS: Analysis of the 12S rDNA and COI revealed that all R. sanguineus s.l. specimens collected across different regions of Colombia clustered within the tropical lineage. Micro-geographical analyses showed that the tick population from Amazonas formed a distinct cluster separated from the other sequences, with moderate Fst and Dxy values. However, no signs of a robust population structure were found within the country. The results of Fu's FS tests, together with the haplotype networks and diversity values, signal a possible population expansion of this tick species in Colombia. CONCLUSIONS: Evidence provided herein supports the tropical lineage as the main circulating lineage in Colombia, exhibiting a general lack of genetic structure except for the Amazonas region.


Asunto(s)
Variación Genética , Rhipicephalus sanguineus/clasificación , Rhipicephalus sanguineus/genética , Infestaciones por Garrapatas/veterinaria , Animales , Colombia , ADN Intergénico/genética , Demografía , Perros/parasitología , Complejo IV de Transporte de Electrones/genética , Filogenia , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN
11.
Sci Rep ; 11(1): 12837, 2021 06 18.
Artículo en Inglés | MEDLINE | ID: mdl-34145318

RESUMEN

HLA class II (HLA-II) genes' polymorphism influences the immune response to Chlamydia trachomatis (Ct), it is considered a sexually transmitted infection. However, associations between HLA-II alleles and Ct-infection have been little explored in humans; this study was thus aimed at determining HLA-DRB1-DQB1 alleles/haplotypes' effect on Ct-infection outcome in a cohort of Colombian women. Cervical sample DNA was used as template for detecting Ct by PCR and typing HLA-DRB1-DQB1 alleles/haplotypes by Illumina MiSeq sequencing. Survival models were adjusted for identifying the alleles/haplotypes' effect on Ct-outcome; bioinformatics tools were used for predicting secreted bacterial protein T- and B-cell epitopes. Sixteen HLA-DRB1 alleles having a significant effect on Ct-outcome were identified in the 262 women analysed. DRB1*08:02:01G and DRB1*12:01:01G were related to infection-promoting events. Only the DQB1*05:03:01G allele related to clearance/persistence events was found for HLA-DQB1. HLA-DRB1 allele homozygous women were associated with events having a lower probability of clearance and/or early occurrence of persistence. Twenty-seven peptides predicted in silico were associated with protective immunity against Ct; outer membrane and polymorphic membrane protein-derived peptides had regions having dual potential for being T- or B-cell epitopes. This article describes HLA-DRB1-DQB1 alleles/haplotypes related to Ct-infection resolution and the peptides predicted in silico which might probably be involved in host immune response. The data provides base information for developing future studies leading to the development of effective prevention measures against Ct-infection.


Asunto(s)
Alelos , Infecciones por Chlamydia/etiología , Chlamydia trachomatis , Predisposición Genética a la Enfermedad , Cadenas beta de HLA-DQ/genética , Cadenas HLA-DRB1/genética , Péptidos/genética , Adulto , Secuencia de Aminoácidos , Mapeo Epitopo , Epítopos , Femenino , Frecuencia de los Genes , Cadenas beta de HLA-DQ/química , Cadenas HLA-DRB1/química , Haplotipos , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Péptidos/química , Adulto Joven
12.
Int J Mol Sci ; 22(4)2021 Feb 05.
Artículo en Inglés | MEDLINE | ID: mdl-33562650

RESUMEN

Plasmodium parasites' invasion of their target cells is a complex, multi-step process involving many protein-protein interactions. Little is known about how complex the interaction with target cells is in Plasmodium vivax and few surface molecules related to reticulocytes' adhesion have been described to date. Natural selection, functional and structural analysis were carried out on the previously described vaccine candidate P. vivax merozoite surface protein 10 (PvMSP10) for evaluating its role during initial contact with target cells. It has been shown here that the recombinant carboxyl terminal region (rPvMSP10-C) bound to adult human reticulocytes but not to normocytes, as validated by two different protein-cell interaction assays. Particularly interesting was the fact that two 20-residue-long regions (388DKEECRCRANYMPDDSVDYF407 and 415KDCSKENGNCDVNAECSIDK434) were able to inhibit rPvMSP10-C binding to reticulocytes and rosette formation using enriched target cells. These peptides were derived from PvMSP10 epidermal growth factor (EGF)-like domains (precisely, from a well-defined electrostatic zone) and consisted of regions having the potential of being B- or T-cell epitopes. These findings provide evidence, for the first time, about the fragments governing PvMSP10 binding to its target cells, thus highlighting the importance of studying them for inclusion in a P. vivax antimalarial vaccine.


Asunto(s)
Antígenos de Protozoos/metabolismo , Plasmodium vivax/metabolismo , Proteínas Protozoarias/metabolismo , Reticulocitos/parasitología , Secuencia de Aminoácidos , Animales , Antígenos de Protozoos/química , Antígenos de Protozoos/genética , Sitios de Unión/genética , Secuencia Conservada , Epítopos/química , Epítopos/genética , Epítopos/metabolismo , Genes Protozoarios , Humanos , Técnicas In Vitro , Malaria Vivax/sangre , Malaria Vivax/parasitología , Modelos Moleculares , Fragmentos de Péptidos/química , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Plasmodium vivax/genética , Plasmodium vivax/patogenicidad , Dominios Proteicos/genética , Proteínas Protozoarias/química , Proteínas Protozoarias/genética , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Reticulocitos/metabolismo , Electricidad Estática
13.
Int J Mol Sci ; 22(2)2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33450807

RESUMEN

Apical membrane antigen 1 is a microneme protein which plays an indispensable role during Apicomplexa parasite invasion. The detailed mechanism of AMA-1 molecular interaction with its receptor on bovine erythrocytes has not been completely defined in Babesia bovis. This study was focused on identifying the minimum B. bovis AMA-1-derived regions governing specific and high-affinity binding to its target cells. Different approaches were used for detecting ama-1 locus genetic variability and natural selection signatures. The binding properties of twelve highly conserved 20-residue-long peptides were evaluated using a sensitive and specific binding assay based on radio-iodination. B. bovis AMA-1 ectodomain structure was modelled and refined using molecular modelling software. NetMHCIIpan software was used for calculating B- and T-cell epitopes. The B. bovis ama-1 gene had regions under functional constraint, having the highest negative selective pressure intensity in the Domain I encoding region. Interestingly, B. bovis AMA-1-DI (100YMQKFDIPRNHGSGIYVDLG119 and 120GYESVGSKSYRMPVGKCPVV139) and DII (302CPMHPVRDAIFGKWSGGSCV321)-derived peptides had high specificity interaction with erythrocytes and bound to a chymotrypsin and neuraminidase-treatment sensitive receptor. DI-derived peptides appear to be exposed on the protein's surface and contain predicted B- and T-cell epitopes. These findings provide data (for the first-time) concerning B. bovis AMA-1 functional subunits which are important for establishing receptor-ligand interactions which could be used in synthetic vaccine development.


Asunto(s)
Eritrocitos/metabolismo , Ligandos , Receptores de Superficie Celular/metabolismo , Animales , Bovinos , Eritrocitos/inmunología , Modelos Moleculares , Conformación Molecular , Péptidos/química , Péptidos/inmunología , Péptidos/metabolismo , Unión Proteica , Dominios y Motivos de Interacción de Proteínas , Receptores de Superficie Celular/química , Receptores de Superficie Celular/inmunología , Relación Estructura-Actividad
14.
Rev. Investig. Salud. Univ. Boyacá ; 8(1): 75-90, 20210000. fig
Artículo en Español | LILACS, COLNAL | ID: biblio-1358961

RESUMEN

Introducción: La babesiosis bovina es causada por parásitos Apicomplexa del género Babesia, siendo la Babesia bovis la especie asociada con cuadros clínicos más graves de la enfermedad. La invasión de B. bovis a los eritro-citos bovinos implica la interacción entre moléculas de los merozoítos del parásito con receptores de las células huésped. Por ende, conocer las proteínas involucradas en este proceso supone un importante paso para entender la biología del parásito. Objetivo: Describir las principales moléculas implicadas en el proceso de invasión de B. bovis a eritrocitos bovinos. Metodología: Se realizó una búsqueda en NCBI, Medline, LILACS y SciELO usando los términos: "Babesia bovis AND invasion process", "MSA-1", "RON2", "AMA-1", "moving junction", "B. bovis AND Vaccine candidates". Con corte en mayo de 2020, había 61 publicaciones disponibles en inglés que describen el estudio de las anteriores proteínas y su participación en la invasión.Resultados: Por ser clave el proceso de invasión a eritrocitos bovinos para la patogénesis de la babesiosis bovina, la revisión encontró 3 proteínas de B. bovis que participan en el reconocimiento e invasión a las células diana: MSA-1, AMA-1 y RON2. Sin embargo, los detalles a nivel molecular para las interacciones inter e intramoleculares aún no se han dilucidado por completo. Conclusiones: Conocer las moléculas involucradas en las interacciones parásito-hospedero permitirá entender cómo ocurre el proceso de invasión de B. bovis a los eritrocitos y, así, evaluar su futura utilidad como componente de una estrategia de control efectiva contra esta parasitosis


Introduction: Bovine babesiosis is caused by Apicomplexas parasites of the genus Babesia, Babesia bovis being the species associated with the most serious clinical conditions of the disease. B. bovisinvasion into the bovine erythrocytes involves the interaction between the parasites merozoites mo-lecules with host cell receptors. Therefore, knowing the proteins involved in the invasion process will enable understanding the parasite biology. Objective: To describe the important molecules involved in the B. bovis invasion process to bovine erythrocytes.Methodology: A search was made on NCBI, Medline, LILACS and SciELO databases using keywords as "Babesia bovis AND invasion process", "MSA-1", "RON2", "AMA-1", "moving junction", "B. bovis AND Vaccine candidates". 61 studies written in English describing the study for proteins that take place during invasion process which have been published until mayo were completely revised. Results: Given that the bovine erythrocyte invasion process is key for the pathogenesis of bovine babesiosis, a review was made where 3 proteins were found to be associated to the recognition and invasion processes of target cells: MSA-1, AMA-1 and RON2. However, the details at molecular level for the inter an intramolecular interaction have not yet been fully elucidated. Conclusions: Study the molecules involved in host-parasite interactions will allow understanding how the B. bovis invasion process to erythrocytes occurs and evaluating their future utility as a component of an effective control strategy for this parasitosis


Introdução: A babesiose bovina é causada por parasitas Apicomplexa do gênero Babesia, sendo a Babesia bovis a espécie associada com os sinais clínicos mais graves da doença. A invasão de B. bovis em eritrócitos bovinos envolve a interação entre moléculas dos merozoítos parasitas com receptores nas células hospedeiras. Por conseguinte, o conhecimento das proteínas envolvidas neste processo é um passo importante para a compreensão da biologia do parasita. Objetivo: Descrever as principais moléculas envolvidas no processo de invasão de B. bovis em eritró-citos bovinos. Metodologia: Foi realizada uma pesquisa no NCBI, Medline, LILACS e SciELO utilizando os termos: "Babesia bovis AND invasion process", "MSA-1", "RON2", "AMA-1", "moving junction", "B. bovis AND Vaccine candidates". Até maio de 2020 estavam disponíveis 61 publicações em inglês, que descreviam o estudo das proteínas acima referidas e o seu envolvimento na invasão. Resultados: Como o processo de invasão de eritrócitos bovinos é fundamental para á patogênese da babesiose bovina, a revisão encontrou 3 proteínas de B. bovis envolvidas no reconhecimento e invasão de células alvo: MSA-1, AMA-1 e RON2. No entanto, os detalhes a nível molecular para as interações Inter e intramoleculares ainda não foram completamente elucidados. Conclusões: A compreensão das moléculas envolvidas nas interações parasita-hospedeiro permitirá entender como ocorre o processo da invasão de B. bovis em eritrócitos e, assim, avaliar sua utilidade futura como componente de uma estratégia efetiva de controle contra esta parasitose


Asunto(s)
Babesia bovis , Babesiosis , Proteínas , Control de Infecciones , Interacciones Huésped-Parásitos
15.
Sci Rep ; 10(1): 7306, 2020 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-32350356

RESUMEN

Several determining factors are involved in HPV infection outcomes; human leukocyte antigen (HLA) polymorphisms have been described as related factors. This study has ascertained the effect of genetic variation on HLA-DRB1 and DQB1 genes on HPV-16/-18/-31/-33/-45 and -58 clearance and redetection in Colombian women. PCR and qPCR were used for viral identification and the Illumina MiSeq system was used for HLA-typing of cervical samples (n = 276). Survival models were adjusted for identifying alleles/haplotypes related to HPV clearance/redetection; L1/L2 protein-epitope binding to MHC-II molecules was also predicted. Significant associations suggested effects favouring or hampering clearance/redetection events depending on the viral type involved in infection, e.g. just DRB1*12:01:01G favoured HPV-16 (coeff: 4.8) and HPV-45 clearance (coeff: 12.65) whilst HPV-18 (coeff: 2E-15), HPV-31 (coeff: 8E-17) and HPV-58 hindered elimination (coeff: 1E-14). An effect was only observed for some alelles when configured as haplotypes, e.g. DRB1*04:07:01G (having the greatest frequency in the target population) was associated with DQB1*02:01:1G or *03:02:03. Epitope prediction identified 23 clearance-related peptides and 29 were redetection-related; eight might have been related to HPV-16/-18 and -58 persistence and one to HPV-18 elimination. HLA allele/haplotype relationship with the course of HPV infection (clearance/redetection) depended on the infecting HPV type, in line with the specific viral epitopes displayed.


Asunto(s)
Alelos , Alphapapillomavirus , Epítopos , Cadenas beta de HLA-DQ , Cadenas HLA-DRB1 , Haplotipos , Infecciones por Papillomavirus , Adulto , Alphapapillomavirus/genética , Alphapapillomavirus/inmunología , Supervivencia sin Enfermedad , Epítopos/genética , Epítopos/inmunología , Femenino , Estudios de Seguimiento , Cadenas beta de HLA-DQ/genética , Cadenas beta de HLA-DQ/inmunología , Cadenas HLA-DRB1/genética , Cadenas HLA-DRB1/inmunología , Humanos , Persona de Mediana Edad , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/inmunología , Infecciones por Papillomavirus/mortalidad , Tasa de Supervivencia
16.
Expert Rev Vaccines ; 19(2): 195-207, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-32077349

RESUMEN

Introduction: Numerous challenges have hampered developing an anti-malarial vaccine against the most widespread malarial parasite worldwide: Plasmodium vivax. Despite the progress achieved in studying proteins in short-term in vitro culture or in experimental models, there is still no clear method for defining which antigens or their regions should be prioritized for including them in a vaccine.Areas covered: The methods used by research groups so far which have focused on the functional analysis of P. vivax blood stage antigens have been reviewed here. A logical strategy orientated toward resolving two of the most commonly occurring problems in designing vaccines against this species has thus been proposed (i.e. the search for candidates and evaluating/ascertaining their functional role in the invasion of such molecules).Expert commentary: Advances in knowledge regarding P. vivax biology have been extremely slow. Only two key receptor-ligand interactions concerning merozoite entry to reticulocytes have been reported during the last 20 years: PvDBP1-DARC and PvRBP2b-CD71. Despite increasing knowledge about the parasite's intimate preference for its host cells, it has yet to be determined which regions of the merozoite molecules characterized to date meet the requirement of inducing protective immune responses effectively blocking heterologous parasite entry to human cells.


Asunto(s)
Vacunas contra la Malaria/administración & dosificación , Malaria Vivax/prevención & control , Plasmodium vivax/inmunología , Animales , Antígenos de Protozoos/inmunología , Humanos , Vacunas contra la Malaria/inmunología , Malaria Vivax/inmunología
17.
Rev. Investig. Salud. Univ. Boyacá ; 6(2): 180-197, 2019. esq
Artículo en Español | LILACS | ID: biblio-1100658

RESUMEN

Introducción. Babesia bovis es el principal agente causal de la babesiosis bovina, una importante enfermedad veterinaria transmitida por garrapatas a nivel mundial. Las estrategias convencionales para controlar esta parasitosis han presentado múltiples limitaciones por lo que el desarrollo de una vacuna basada en antígenos representa una estrategia apropiada para la prevención y el tratamiento. Objetivo. Describir los aspectos relevantes del ciclo de vida del parásito B. bovis, la epidemiología, diagnóstico y la aplicación de diferentes estrategias usadas para controlar esta parasitosis. Además, se discuten potenciales puntos de intervención para desarrollar una vacuna contra este parásito. Metodología. Se realizó una búsqueda en las bases de datos usando los términos: "Babesia bovis AND lyfe cycle", "B. bovis vaccine and Vaccine candidates", entre otras. Los estudios con mayor pertinencia publicados hasta la actualidad se revisaron completamente. Resultados. Los detalles de la biología de parásito B. bovis y el proceso molecular usado para ocasionar la enfermedad en el hospedador son poco conocidos, lo que explica que el desarrollado de estrategias para el control de esta parasitosis no hayan sido del todo eficientes. Por lo tanto, se requiere diseñar nuevas medidas, por ejemplo, desarrollar vacunas de nueva generación basadas en un enfoque funcional que permitan mejorar las condiciones de sanidad animal. Conclusiones. Comprender el complejo ciclo de vida de B. bovis permitirá estudiar las interacciones huésped-parásito-garrapata e identificar moléculas implicadas en la adhesión/invasión celular para evaluar su utilidad como componente de una vacuna que controle esta parasitosis.


Introduction. Babesia bovis is the main causal agent of babesiosis bovine, one important veterinary diseases transmitted by ticks worldwide. Conventional strategies to control this parasitosis have shown several limitations and therefore the development of a vaccine will be an appropriate strategy for prevention and treatment. Objective. To describe relevant aspects of B. bovis parasite's life cycle, the epidemiology, diagnosis, the application of different strategies used to control this parasitosis. In addition, potential points of intervention to develop a vaccine against this parasite has been discussed. Methodology. A search was made using keywords as "Babesia bovis AND lyfe cycle", "B. bovis vaccine and Vaccine candidates" and others. The most relevant studies published to date were completely revised. Results. The details of the B.bovis parasite biology and the molecular process used to cause disease in the host had not been describe in deep; explaining that the development of strategies for the control of this parasitosis have not been entirely efficient. Therefore, it is necessary to design new procedures, for example, to develop new generation vaccines based on a functional approach which improve the animal health conditions. Conclusions. Understand the B. bovise's life cycle complex will allow the host-parasite-tick interactions study and the identification of molecules involved in cell adhesion / invasion to evaluate its usefulness as a vaccine component that controls this parasitosis.


Introdução. Babesia bovis é o principal agente causador da babesiose bovina, uma importante doença veterinária transmitida por carrapatos a nível mundial. As estratégias convencionais para o controle das parasitoses têm presentado múltiplas limitações pelo que o desenvolvimento de uma vacina baseada em antígenos representa uma estratégia apropriada para a prevenção e o tratamento. Objetivo. Descrever os aspectos relevantes do ciclo de vida do parasita B. bovis, a epidemiologia, diagnostico e aplicação de diferentes estratégias usadas para o controle desta parasitose. Além disso, são discutidos possíveis pontos de intervenção para o desenvolvimento de uma vacina contra o parasita. Metodologia. Uma pesquisa foi realizada nas bases de dados usando os termos: "Babesia bovis AND lyfe cycle", "B. bovis vaccine and Vaccine candidates", entre outras. Os estudos mais relevantes publicados até o momento foram completamente revisados. Resultados. Os detalhes da biologia do parasita B. bovis e o processo molecular usado para causar doenças no hospedeiro é pouco conhecido, o que explica que o desenvolvimento de estratégias para o controle desta parasitose não foram completamente eficientes. Portanto, é necessário projetar novas medidas, por exemplo, desenvolver vacinas de nova geração com base em uma abordagem funcional que permita melhorar as condições de saúde animal. Conclusões. Compreender o complexo ciclo de vida de B. bovis permitirá estudar as interações hospede­parasita­carrapatos e identificar moléculas envolvidas na adesão/invasão celular para avaliar sua utilidade como componente de uma vacina que controla essa parasitose.


Asunto(s)
Vacunas , Babesiosis , Babesia bovis , Estadios del Ciclo de Vida , Antígenos
18.
Front Genet ; 9: 372, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30250483

RESUMEN

The RBSA protein is encoded by a gene described in Plasmodium species having tropism for reticulocytes. Since this protein is antigenic in natural infections and can bind to target cells, it has been proposed as a potential candidate for an anti-Plasmodium vivax vaccine. However, genetic diversity (a challenge which must be overcome for ensuring fully effective vaccine design) has not been described at this locus. Likewise, the minimum regions mediating specific parasite-host interaction have not been determined. This is why the rbsa gene's evolutionary history is being here described, as well as the P. vivax rbsa (pvrbsa) genetic diversity and the specific regions mediating parasite adhesion to reticulocytes. Unlike what has previously been reported, rbsa was also present in several parasite species belonging to the monkey-malaria clade; paralogs were also found in Plasmodium parasites invading reticulocytes. The pvrbsa locus had less diversity than other merozoite surface proteins where natural selection and recombination were the main evolutionary forces involved in causing the observed polymorphism. The N-terminal end (PvRBSA-A) was conserved and under functional constraint; consequently, it was expressed as recombinant protein for binding assays. This protein fragment bound to reticulocytes whilst the C-terminus, included in recombinant PvRBSA-B (which was not under functional constraint), did not. Interestingly, two PvRBSA-A-derived peptides were able to inhibit protein binding to reticulocytes. Specific conserved and functionally important peptides within PvRBSA-A could thus be considered when designing a fully-effective vaccine against P. vivax.

19.
Malar J ; 17(1): 301, 2018 Aug 20.
Artículo en Inglés | MEDLINE | ID: mdl-30126427

RESUMEN

Understanding the life cycle of Plasmodium vivax is fundamental for developing strategies aimed at controlling and eliminating this parasitic species. Although advances in omic sciences and high-throughput techniques in recent years have enabled the identification and characterization of proteins which might be participating in P. vivax invasion of target cells, exclusive parasite tropism for invading reticulocytes has become the main obstacle in maintaining a continuous culture for this species. Such advance that would help in defining each parasite protein's function in the complex process of P. vivax invasion, in addition to evaluating new therapeutic agents, is still a dream. Advances related to maintenance, culture medium supplements and the use of different sources of reticulocytes and parasites (strains and isolates) have been made regarding the development of an in vitro culture for P. vivax; however, only some cultures having few replication cycles have been obtained to date, meaning that this parasite's maintenance goes beyond the technical components involved. Although it is still not yet clear which molecular mechanisms P. vivax prefers for invading young CD71+ reticulocytes [early maturation stages (I-II-III)], changes related to membrane proteins remodelling of such cells could form part of the explanation. The most relevant aspects regarding P. vivax in vitro culture and host cell characteristics have been analysed in this review to explain possible reasons why the species' continuous in vitro culture is so difficult to standardize. Some alternatives for P. vivax in vitro culture have also been described.


Asunto(s)
Técnicas Microbiológicas/métodos , Parasitología/métodos , Plasmodium vivax/crecimiento & desarrollo , Animales , Medios de Cultivo/química , Reticulocitos/parasitología
20.
Artículo en Español | LILACS | ID: biblio-900322

RESUMEN

RESUMEN: Objetivo: Creación de un currículo de competencias mínimas en Cariología, para la formación de los Cirujano-Dentistas egresados de las escuelas de Odontología de Chile. Metodologías: A partir de una reunión de académicos de las Universidades de Talca y de Chile (año 2011), se elaboró una propuesta de currículo inicial, basado en los dominios propuestos por la Unión Europea (Schulte AG y cols). Durante el año 2016, dicha propuesta fue analizada mediante diálogos digitales y grupos de trabajo, con la participación del 96% de las Escuelas de Odontología existentes en el país, que concluyeron en un documento intermedio. Este documento fue analizado, discutido y perfeccionado durante el Taller para el Desarrollo de un Currículo de Competencias Mínimas en Cariología para las Escuelas de Odontología Chilenas (22/Mayo/2017, Talca, organizado por la Universidad de Talca y la Universidad de Chile) con la asistencia de representantes del 96% de las escuelas dentales chilenas, Ministerio de Salud de Chile, Colegio de Cirujano-Dentistas de Chile y con la asesoría de los profesores de Cariología Dres. Margherita Fontana y Carlos González-Cabezas (Universidad de Michigan, Ann Arbor, EEUU). Cada grupo de trabajo revisó el documento y envió nuevos comentarios, los que fueron incorporados en el documento final por una comisión asesora. Resultados: El documento del Currículo en Cariología se organizó en 5 Dominios: 1. Conocimientos base; 2. Determinación de Riesgo, diagnóstico de caries y detección de lesiones de caries; 3. Toma de decisiones y manejo preventivo no operatorio; 4. Toma de decisiones y manejo operatorio y 5. Cariología basada en la evidencia, en la práctica clínica y de salud pública. Se consensuaron las definiciones operacionales, las competencias principales y las sub-competencias para cada uno de los dominios. Las sub-competencias fueron clasificadas en tres niveles: A: Ser competente en; B: Tener conocimientos sobre y C: Estar familiarizado con. El documento final fue enviado a todos los participantes del taller para su aprobación y difusión en cada una de las instituciones involucradas. Conclusiones: Se logró, por medio de consenso, la construcción del Currículo de Competencias mínimas en Cariología para estudiantes de pregrado de Odontología en las universidades chilenas.


ABSTRACT: Objective: Development of a minimum set of competencies in Cariology that every dentist graduated from a Dental School in Chile must have. Methodology: Starting from a meeting of scholars from the Universities of Talca and Chile (year 2011), an initial proposal for a curriculum was developed, based on the domains proposed by the European Cariology Curriculum (Schulte, et al, 2011). During 2016, this proposal was discussed through online dialogues and working groups, with the participation of 95.2% of the Chilean dental schools, which resulted in an intermediate document. This document was analyzed, discussed and refined during the Workshop for the Development of a Curriculum of Minimum Competencies in Cariology for Chilean Dental Schools (May 22, 2017, Talca, organized by the Universities of Talca and Chile) with the attendance of representatives from 95.2% of the Chilean dental schools, the Chilean Ministry of Health, Chilean College od Dentists and with the assistance of the professors of Cariology Margherita Fontana and Carlos González-Cabezas (University of Michigan, Ann Arbor, USA). Each working group revised the document and provided feedback, which was incorporated in the final document by an advisory committee, elected on the day of the workshop, including the authors of the present article. Results: The Cariology Curriculum was organized in 5 Domains: 1. Basic knowledge; 2. Risk assessment, caries diagnosis and caries lesion detection; 3. Decision-making and non-operative preventive treatment; 4. Decision making and operative treatment; and 5. Evidence-based, clinical and public health practice. Operational definitions, main competencies and sub-competencies for each domain were agreed. Sub-competencies were classified into three levels: A: Be competent in; B: Have knowledge about, and C: Be familiar with. The final document was sent to all the participants of the workshop for dissemination in each of the institutions involved. Conclusions: The development of the Competency-based Curriculum in Cariology for undergraduate dental students at Chilean universities was achieved through consensus.


Asunto(s)
Humanos , Facultades de Odontología , Estudiantes de Odontología , Universidades , Curriculum , Caries Dental , Educación , Chile
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