São Paulo, Brazil


São Paulo, Brazil
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Limon I.D.,Autonomous University of Puebla | Ramirez E.,Autonomous University of Puebla | Diaz A.,Autonomous University of Puebla | Diaz A.,Laboratorio Experimental Of Enfermedades Neurodegenerativas | And 5 more authors.
Neuroscience Letters | Year: 2011

Sialic acid in glycoconjugates participates in important cellular functions associated with normal development, growth, and communication. Therefore we evaluated the sialylation pattern and memory deficits caused by the injection of Aβ(25-35) into the hippocampus (Hp) of rats. The eight-arm maze spatial-learning and memory test indicated that the injection of Aβ(25-35) into subfield CA1 of the Hp impaired both learning and memory. The sialylation pattern was examined using sialic acid-specific lectins. Our results showed that Maackia amurensis agglutinin (MAA, specific for Neu5Acα2,3Gal) showed reactivity in the CA1 and dentate gyrus (DG) subfields of the Hp mainly in the group injected with vehicle, whereas Macrobrachium rosenbergii lectin (MRL, specific for Neu5,9,7Ac) and Sambucus nigra agglutinin (SNA, specific for Neu5Acα2,6Gal-GalNAc) had increased reactivity in the CA1 and DG subfields of the Hp in the Aβ(25-35)-injected group. The staining pattern of the antibody specific for polysialic acid (a linear homopolymer of α-2,8-linked sialic acid) increased in the CA1 and DG subfields of the Hp of the Aβ(25-35) group compared to the control group. Our results suggest that injection of Aβ(25-35) causes impairment in spatial memory and alters the sialylation pattern in response to compensatory reorganization and-or sprouting of dendrites and axons of the surviving neurons. © 2011 Elsevier Ireland Ltd.

Ponce De Leon P.,Bioquimica | Ponce De Leon P.,Laboratorio Of Parasitologia | Di Vita S.,Estudiante de Bioquimica | Di Vita S.,Laboratorio Of Parasitologia | And 4 more authors.
Acta Bioquimica Clinica Latinoamericana | Year: 2011

Erythrocyte aggregation affects microcirculation and its study is important in vascular diseases. It was communicated that Ascaris lumbricoides can capture erythrocyte sialic acid (SA) and alter the anionic charge on the red cell. The aim of this work was to study SA capture by A. lumbricoides larvae incubated in vivo with erythrocytes. Work was performed with concentrated larvae ([ALLC]) incubated in 4 tubes with phosphate buffer and antibiotics. Group O erythrocytes were added in two Tubes. The remaining were Controls. They were incubated at 37 °C (5% CO2) for 24 and 28 hours. The larvae were separated, collected, concentrated and counted microscopically (larvae/mL: [ALLC]1:1500-1700; [ALLC]3:1600-1800; [ALLC]2 and 4:200-400). Aggregation Inhibition by Polybrene (AIP) and Blue Alcian (BA) techniques were used. AIP showed a significant difference between Polybrene Titers diluted with physiological solution and with [ALLC]1 and 2, which were incubated with erythrocytes 24 and 48 hours respectively. There was no change in the Title of the corresponding Controls. BA performed in [ALLC]1 and [ALLC]3 determined CapSAC = 6.65% ±0.36 and SAC[CLAL]3 % = 0.67% ±0.36. The experience showed SA capture by larvae incubated in vivo with erythrocytes and it suggested that they have no intrinsic SA. SA kidnapping during the larval migration could be important in parasite-host interaction.

Yoshioka C.R.M.,University of Sao Paulo | Martinez M.B.,University of Sao Paulo | Brandileone M.C.C.,Federal University of São Paulo | Brandileone M.C.C.,Instituto Adolfo Lutz IAL | And 5 more authors.
Jornal de Pediatria | Year: 2011

Objectives: To identify the most common pneumococcal serotypes in children hospitalized with invasive pneumonia, correlate isolated serotypes with those included in conjugate vaccines, and ascertain the sensitivity of the isolated pneumococcal strains to penicillin and other antibiotics. Methods: From January 2003 to October 2008, a retrospective study of hospitalized children with a diagnosis of Streptococcus pneumoniae pneumonia was conducted at the university hospital of Universidade de São Paulo. Criteria for inclusion were: age greater than 29 days and less than 15 years, radiological and clinical diagnosis of pneumonia, and isolation of Streptococcus pneumoniae in blood cultures and/or pleural effusion. Results: The study included 107 children. The most common serotypes were 14 (36.5%), 1 (16%), 5 (14.6%), 6B (6.3%) and 3 (4.2%). The proportion of identified serotypes contained in the heptavalent, 10-valent and 13-valent conjugate vaccines was 53.1, 86.5, and 96.9%, respectively. Pneumococcal strains were sensitive to penicillin (minimum inhibitory concentration, MIC ≤ 2 ?g/mL) in 100 cases (93.5%) and displayed intermediate resistance (MIC = 4 μg/mL) in 7 cases (6.5%). No strains were penicillin-resistant (MIC ≥ 8 μg/mL) according to the Clinical and Laboratory Standards Institute 2008 standards. Tested isolates were highly sensitive to vancomycin, rifampicin, ceftriaxone, clindamycin, erythromycin, and chloramphenicol. Conclusions: Our results confirm a significant potential impact of conjugate vaccines, mainly 10-valent and 13-valent, on invasive pneumonia. Furthermore, susceptibility testing results show that penicillin is still the treatment of choice for invasive pneumonia in our setting. Copyright © 2011 by Sociedade Brasileira de Pediatria.

Zotta C.M.,Tecnico Quimico | Chinen I.,Bioquimica | Lavayen S.,Licenciada en Quimica | Carbonari C.,Bioquimica | And 3 more authors.
Acta Bioquimica Clinica Latinoamericana | Year: 2014

Shiga toxin-producing Escherichia coli (STEC), especially the serotype O157:H7, is associated with the occurrence of sporadic cases and outbreaks of bloody diarrhea (DS) and hemolytic uremic syndrome (HUS). Other STEC serotypes such as O26:H11, O103:H2, O111:NM, O113:H21, and O145:NM can also cause severe human illness. In Argentina O157:H7 is prevalent, followed in frequency by serotype O145:NM. The aim of this study was to determine the genetic diversity and clonal relationship of E. coli O145:NM/ H27 strains isolated in different locations of the Buenos Aires province, in the period 2004-2009. A total of 17 strains isolated from HUS (9), DS (5) and asymptomatic contacts (3) were characterized by PCR to detect stx1, stx2, rfb0157, eae and ehxA genes, and pulsed-field gel electrophoresis (XbaIPFGE) to establish the genetic diversity and the clonal relationship. All isolates were characterized as stx2/eae/ehxA. By XbaI-PFGE, 14 different patterns were established, with a single cluster identified. A regional database of E. coli O145:NM/H27 was created, which will monitor the I-PFGE profiles of the circulating strains in order to identify the probable occurrence of an outbreak in the community and report to the authorities to implement control measures.

Holod S.A.,Bioquimica Especialista en Bioquimica Clinica | Pengue C.,Bioquimica | Del Carmen Campos M.,Bioquimica | Pittaluga S.G.,Bioquimico | Raimondi R.A.,Bioquimica Especialista en Bioquimica Clinica
Acta Bioquimica Clinica Latinoamericana | Year: 2011

Measurement of blood gas, as another sample, involves three phases: preanalytical, analytical and postanalytical. The aim of this study is to evaluate the preanalytical phase comparing samples obtained from different syringes and the effect of storage time; to study the analytical performance; to compare the agreement between two instruments, and to analyse if the results were satisfactory taking into account CLIA specifications. Two microanalyzers were used, in which pH, pCO2 and pO2 were tested. Within-day imprecisions (CVi) and between-day imprecisions (CVe) were obtained with control materials. Two hundred and thirty-nine patient-samples were used;20 were used for the comparison between samples obtained with heparinized syringes (sodium liquid heparin) and dry lithium heparin);110 were processed to evaluate the effect of storage time, and 109 for the comparison between the analyzers. CVi and CVe were acceptable for the three parameters. The difference between the different syringes did not exceed the acceptable limits. No significant difference was noticed until 120 min of storage. The correlation coefficients for processed samples in both instruments were 0.931 for pH, 0.985 for PCO 2 and 0.950 for PO2. The bias was acceptable as the clinical equivalence for the three parameters. Evaluating the results between identical instruments and introducing a systematic quality program has an important role in obtaining a progressive decrease of the total error between them, and using one or the other without distinction.

Autoimmune thyroid disease (ATD) is the most common disorder that leads to thyroid gland dysfunction. ATD manifests in various clinical forms, such as Hashimoto's Thyroiditis (HT) and Graves' Disease (GD). The relation between HT and GD has been discussed for decades. Even if they greatly differ in their clinical features and treatment, some people believe they are the opposite sides of the same coin. In their pathogenesis, they share some mechanisms, such as genetic susceptibility, shown by the fact that they tend to occur both in the same person and within the same family. However, differences in the local micro-environment can determine the distinct phenotypic expression or the switch from one disease to the other. The aim of this monograph was to investigate similarities and differences between HT and GD at the diverse stages leading to the development of autoimmunity. Copyright © 2012 por la Sociedad Argentina de Endocrinología y Metabolismo.

Garda H.A.,National Autonomous University of Mexico | Toledo J.D.,Bioquimica | Gonzalez M.C.,Ciencias Biologicas | Prieto E.D.,Bioquimica | And 4 more authors.
Acta Bioquimica Clinica Latinoamericana | Year: 2013

Apolipoprotein A-I (apoAI) is the major protein component of high density lipoprotein (HDL), whose serum level is inversely correlated with atherogenic risk. Antiatherogenic properties are largely attributed to its key role in re verse cholesterol transport (RCT), a process that removes cholesterol excess from peripheral tissues. ApoAI is an amphitropic protein that almost exclusively contains amphipathic a-helices, and presents a large conformational flexibility that is crucial for its functional cycle, in which it inter-converts into different states: free or bound to membranes, or into a lipoprotein complex variety of different sizes, compositions and morphologies. This report reviews the current knowledge of the structure and lipid interaction properties of apoAI, in relation with HDL biogenesis and function in RCT. In particular, focus is made on the apoAI configuration in discoidal HDL; as well as on the interaction with lipids, and the importance for cellular cholesterol efflux, of an amphipathic α-helix pair having a particular distribution of the charged residues and that locate at the center of the apoAI molecule. © 2013 Federación Bioquímica de la Provincia de Buenos Aires.

Lopardo H.A.,Dr. en Ciencias Bioquimicas | Borgnia D.,Bioquimica | Mastroianni A.,Tecnico Of Laboratorio
Acta Bioquimica Clinica Latinoamericana | Year: 2012

Two extendedly-used swab transport devices with Stuart medium using Streptococcus pyogenes, Haemophilus influenzae, Neisseria gonorrhoeae and Streptococcus pneumoniae reference strains, were compared. Copan Venturi Transystem® (Copan Italia Spa, Brescia, Italy) was significantly more effective than Eurotubo (Deltalab, Rubí, Barcelona, Spain), probably because the narrowing of the tube, just at the beginning of the semisolid column (Venturi system), would yield a better conservation of diffrerent organisms. © 2012 Federacion Bioquimica de la Provincia de Buenos Aires.

PubMed | Complejo Hospitalario Universitario Of Ourense, University of Vigo and BIOQUIMICA
Type: Journal Article | Journal: Revista espanola de enfermedades digestivas : organo oficial de la Sociedad Espanola de Patologia Digestiva | Year: 2015

Although colorectal carcinogenesis has been intensively studied, the published investigations do not provide a consistent description of how different carbohydrate determinants of colorectal epithelium are modified in colorectal cancer (CRC).This study is an attempt to characterize the terminal fucosylation steps responsible for the synthesis of mono- Le(a)/Le(x)- and difucosylated -Le(b)/Le(y)- Lewis antigens in healthy and tumour CRC tissue.An immunohistochemical study of Lewis antigens expression was undertaken, along with screening of the fucosyltransferase (FT) activities involved in their synthesis, on healthy and tumour samples from 18 patients undergoing CRC.Analysis of alpha(1,2/3/4)FT activities involved in the sequential fucosylation of cores 1 and 2 showed significant increases in tumour tissue. Expressed as microU/mg and control vs. tumour activity (pfrom Wilcoxons test), the FT activities for Le(a)/Le(b) synthesis were: lacto-N-biose alpha(1,2)/alpha(1,4)FT, 65.4 19.0 vs. 186 35.1 (p< 0.005); lacto-N-fucopentaose 1 alpha(1,4)FT, 64.9 11.9 vs. 125.4 20.7 (p< 0.005); Le(a) alpha(1,2)FT, 56.2 7.2 vs. 130.5 15.6 (p< 0.001). Similarly, for Le(x)/Le(y) synthesis were: N-acetyllactosamine alpha(1,2)-/alpha(1,3)FT, 53.4 12.2 vs. 108.1 18.9 (p< 0.001); 2-Fucosyl-N-acetyllactosamine alpha(1,3)FT, 61.3 10.7 vs. 126.4 22.9 (p< 0.001); 2-Fucosyllactose alpha(1,3)FT, 38.9 10.9 vs. 143.6 28.9 (p< 0.001); 2-Methyllactose alpha(1,3)FT, 30.9 4.8 vs. 66.1 8.1 (p< 0.005); and Le(x) alpha(1,2)FT, 54.3 11.9 vs. 88.2 14.4 (p< 0.001). Immunohistochemical Le(y) expression was increased (p< 0.01 according to Wilcoxons test) in tumour tissue, with 84.6% of specimens being positive: 7.7% weak, 15.4% moderate and 61.5% high intensity.Results suggest the activation of the biosynthesis pathways of mono- and difucosylated Lewis histo-blood antigens in tumour tissue from CRC patients, leading to the overexpression of Le(y), probably at the expense of Le(x).

Spalvieri M.P.,Bioquimica | Oyola M.E.,Bioquimica
Acta Bioquimica Clinica Latinoamericana | Year: 2011

Statins are a group of drugs widely used in the treatment of dyslipidemia. Its mechanism of action is based on inhibiting the enzyme 3 hydroxi 3 methyl glutaryl-CoA reductase (HMG-CoA reductase), which catalyses a key step in cholesterol synthesis, the conversion of HMG-CoA to mevalonate. Inhibition of the enzyme by statins results in decreased hepatic cholesterol synthesis and increased expression of LDL receptors on hepatocytes. Statins are generally well tolerated; the most important adverse effects are associated myopathy and asymptomatic increases in liver transaminases. The aims of this paper are to try to establish the incidence of adverse effects caused by statins used in dyslipidemic patients, mainly myositis; determine the percentage of patients who begin treatment without knowing the initial value of CK, and the percentage of individuals with elevated CK more than ten times the normal value in an asymptomatic way; and determine which are the most frequently used statins are, and which of them present a higher incidence of adverse effects.

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