The quest for an ideal biomaterial perfectly matching the microenvironment of the surrounding tissues and cells is an endless challenge within biomedical research, in addition to integrating this with a facile and sustainable technology for its preparation. Engineering hydrogels through click chemistry would promote the sustainable invention of tailor-made hydrogels. Herein, we disclose a versatile and facile catalyst-free click chemistry for the generation of an innovative hydrogel by combining chondroitin sulfate (CS) and polyethylene glycol (PEG).
View Article and Find Full Text PDFLecithin-cholesterol acyltransferase (LCAT), an enzyme that participates in lipoprotein metabolism, plays an important role in cholesterol homeostasis. Mutations in the gene can cause two rare genetic disorders: familial LCAT deficiency (FLD), which is characterized by corneal opacities, normocytic anemia, dyslipidemia, and proteinuria progressing to chronic renal failure, and fish-eye disease (FED), which causes dyslipidemia and progressive corneal opacities. Herein, we report six suspected cases of FLD in the backlands of Piauí, located in northeast Brazil.
View Article and Find Full Text PDFBackground: With the emergence of the new coronavirus pandemic (COVID-19), distance learning, especially that mediated by information and digital communication technologies, has been adopted in all areas of knowledge and at all levels, including medical education. Imminently practical areas, such as pathology, have made traditional teaching based on conventional microscopy more flexible through the synergies of computational tools and image digitization, not only to improve teaching-learning but also to offer alternatives to repetitive and exhaustive histopathological analyzes. In this context, machine learning algorithms capable of recognizing histological patterns in kidney biopsy slides have been developed and validated with a view to building computational models capable of accurately identifying renal pathologies.
View Article and Find Full Text PDFHum Immunol
January 2021
To improve the availability of three-dimensional (3D) structures of HLA molecules, we created the pHLA3D database. In its first version, we modeled and published 106 3D structures of HLA class I molecules from the HLA-A, HLA-B, and HLA-C loci. This paper presents an update of this database, providing more 127 3D structures of HLA class II molecules (41 DR, 42 DQ, and 44 DP), predicted via homology modeling with MODELLER and SWISS-MODEL.
View Article and Find Full Text PDFBackground And Objectives: This work aims to present the expert system EpAssistant, a platform algorithm designed to accurately and automatically identify the EPLETS specificities of anti-HLA (Human Leukocyte Antigen) antibodies in the sera of transplantation candidates.
Materials And Methods: RESULTS: As preliminary results, we present the development and establishment of the EpAssistant platform. EpAssistant analyses can be performed for Class I (-A, B and C) and Class II (-DR, -DQ and -DP) HLA molecules.
Introduction: Fabry disease (FD) is a disorder caused by mutations in the gene encoding for lysosomal enzyme α-galactosidase A (α-GAL). Reduced α-GAL activity leads to progressive accumulation of globotriaosylceramide (Gb3), also known as CD77. The recent report of increased expression of CD77 in blood cells of patients with FD indicated that this molecule can be used as a potential marker for monitoring enzyme replacement therapy (ERT).
View Article and Find Full Text PDFAim: To produce and test recombinant multiepitope proteins as an alternative assay for the serological diagnosis of cryptococcosis.
Materials & Methods: Previously, synthetic peptides were used to detect anti-Cryptococcus antibodies, and in silico analyses showed that the union of peptides would improve the results. Here, the coding sequences of these peptides were assembled into synthetic genes.
Background: The compatibilities between donors and recipients are extremely important for evaluating the immunological risks of transplants. One challenge faced by data analysis tools is the transformation of complex data into simple, intuitive, and important information that can be used to resolve contemporary problems. To address this challenge, we developed the EpViX software to perform epitope reactivity analyses and automated epitope virtual crossmatching.
View Article and Find Full Text PDFIntroduction: Fabry disease is a lysosomal storage disorder due to abnormalities in the GLA gene (Xq22). Such changes result in the reduction/absence of activity of the lysosome enzyme α-GAL, whose function is to metabolize globotriaosylceramide (Gb3). Renal disease is a major clinical outcome of the accumulation of Gb3.
View Article and Find Full Text PDFTranspl Immunol
November 2015
One of the challenges facing solid organ transplantation programs globally is the identification of low immunological risk donors for sensitized recipients by HLA allele genotype. Because recognition of donor HLA alleles by host antibodies is at the core of organ rejection, the objective of this work was to develop a new version of the EpHLA software, named EpViX, which uses an HLAMatchmaker algorithm and performs automated epitope virtual crossmatching at the initiation of the organ donation process. EpViX is a free, web-based application developed for use over the internet on a tablet, smartphone or computer.
View Article and Find Full Text PDFObjective: this study aimed to report the allele and haplotype frequencies of volunteer bone marrow donors (VBMD) from the state of Rio Grande do Norte (RN) who were enrolled in the Brazilian Volunteer Bone Marrow Donor Registry (REDOME).
Methods: the sample comprised 12,973 VBMD who had their allele and haplotype frequencies calculated by Arlequin 3.5.
The International Registry of Antibody-Defined HLA Epitopes (http://www.epregistry.com.
View Article and Find Full Text PDFAim: To determine the immunoreactivity of synthetic Cryptococcus-derived peptides.
Materials & Methods: A total of 63 B-cell epitopes from previously identified Cryptococcus gattii immunoreactive proteins were synthesized and evaluated as antigens in ELISAs. The peptides were first evaluated for their ability to react against sera from immunocompetent subjects carrying cryptococcal meningitis.
This study investigated the potential relationship between the expression levels of lysosome-associated membrane proteins (LAMP) 1 and 2 and responses to enzyme replacement therapy (ERT) in the members of a single family with Fabry disease (FD). LAMP levels were assessed by flow cytometry in leukocytes from 17 FD patients who received an eight-month course of ERT course and 101 healthy individuals. We found that phagocytic cells from the FD patients had higher expression levels of both LAMP-1 and LAMP-2, relative to the levels in phagocytes from the healthy controls (p=0.
View Article and Find Full Text PDFAccumulation of globotriaosylceramide (Gb3) and other neutral glycosphingolipids with galactosyl residues is the hallmark of Fabry disease, a lysosomal storage disorder caused by deficiency of the enzyme alpha-galactosidase A (α-gal A). These lipids are incorporated into the plasma membrane and intracellular membranes, with a preference for lipid rafts. Disruption of raft mediated cell processes is implicated in the pathogenesis of several human diseases, but little is known about the effects of the accumulation of glycosphingolipids on raft dynamics in the context of Fabry disease.
View Article and Find Full Text PDFAim: To identify immunoreactive proteins of Cryptococcus gattii genotype VGII and their B-cell epitopes.
Materials & Methods: We combined 2D gel electrophoresis, immunoblotting and mass spectrometry to identify immunoreactive proteins from four strains of C. gattii genotype VGII (CG01, CG02, CG03 and R265).
Transpl Immunol
June 2012
Unlabelled: The HLAMatchmaker algorithm, which allows the identification of “safe” acceptable mismatches (AMMs) for recipients of solid organ and cell allografts, is rarely used in part due to the difficulty in using it in the current Excel format. The automation of this algorithm may universalize its use to benefit the allocation of allografts. Recently, we have developed a new software called EpHLA, which is the first computer program automating the use of the HLAMatchmaker algorithm.
View Article and Find Full Text PDFAnalysis of HLA data involves queries on web portals, whose search parameters are data stored in laboratories' databases. In order to automate these queries, one approach is to structure laboratory data into a database and to develop bioinformatic tools to perform the data mapping. In this context, we developed the LabSystem Gen tool that allows users to create a Laboratory Information System, without programming.
View Article and Find Full Text PDFJ Bras Pneumol
June 2012
Objective: To identify mycobacterial species in the sputum of patients suspected of having pulmonary tuberculosis and to determine the impact that the acquisition of this knowledge has on the therapeutic approach.
Methods: We evaluated 106 patients suspected of having pulmonary tuberculosis and referred to the pulmonology department of a public hospital in the city of Teresina, Brazil. Morning sputum specimens were evaluated for the presence of mycobacteria by sputum smear microscopy and culture.
Mem Inst Oswaldo Cruz
September 2011
Throughout Brazil, Cryptococcus neoformans is the cause of cryptococcosis, whereas Cryptococcus gattii is endemic to the northern and northeastern states. In this study, the molecular types of 63 cryptococcal isolates recovered from the cerebrospinal fluid of meningitis patients diagnosed between 2008-2010 in Teresina, Piauí, Brazil, were analysed. Out of the 63 patients, 37 (58.
View Article and Find Full Text PDFTranspl Immunol
December 2011
Unlabelled: The global challenge for solid organ transplantation programs is to distribute organs to the highly sensitized recipients. The purpose of this work is to describe and test the functionality of the EpHLA software, a program that automates the analysis of acceptable and unacceptable HLA epitopes on the basis of the HLAMatchmaker algorithm. HLAMatchmaker considers small configurations of polymorphic residues referred to as eplets as essential components of HLA-epitopes.
View Article and Find Full Text PDFResearch has investigated the participation of zinc transport proteins and metallothionein in the metabolism of this mineral. However, studies about the genetic expression of these proteins in obese patients are scarce. The study determined the expression of zinc transporter protein codifying genes (ZnT-1, Zip-1 and Zip-3) and of metallothionein in 55 obese women, aged between 20 and 56 years.
View Article and Find Full Text PDFArq Bras Oftalmol
August 2009
Purpose: To determine plasma and erythrocyte zinc concentrations in elderly with and without senile cataract in a tertiary eye care center at Teresina-Piauí.
Methods: A quantitative, transversal and controlled study was developed at the Hospital de Olhos Francisco Vilar, Piauí, Brasil. Fifty-six elderly subjects (37 females, 19 males) with no known conditions that modify zinc blood levels or increase risk of cataract were included.
This study evaluated nutritional status linked to zinc levels in 239 randomly selected children at crèches in Teresina, Brazil, aged 3 to 6. Blood samples were collected after fasting of 10 h. Erythrocytary zinc levels were determined through flame atomic absorption spectrophotometry.
View Article and Find Full Text PDFThe objective of this study was to assess urinary excretion of zinc and evaluation parameters of metabolic control in type 2 diabetic patients. Thirty-one type 2 diabetic patients, of both genders, with 5.8 +/- 5.
View Article and Find Full Text PDF