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In order to isolate antioxidant peptides from oats globulin hydrolyzed alcalase, an antioxidant peptide was isolated and purified using ultra-filtration and ion-exchange chromatography. Hydroxyl and 1,1-diphenyl-2-pycrylhydrazyl (DPPH) radical scavenging capacity was analyzed to evaluate the antioxidant activity of peptide. Five fractions were obtained after ultra-filtration, fraction with molecular weight >10KDa showed the strongest hydroxyl and DPPH radical scavenging ability of 58.38 ± 0.87% and 24.53 ± 0.53% (p < 0.05). Fraction C which was purified via ion-exchange chromatography, exhibited the maximum antioxidant activity (IC50 of hydroxyl and DPPH radical scavenging ability was 1.83 ± 0.03 mg mL−1 and 4.11 ± 0.07 mg mL−1) among other fractions (p < 0.05). Subsequently, five antioxidant peptides were identified by electrospray ionization mass spectrometry (ESI-MS/MS), with the amino acid sequence of IRIPIL, FLKPMT, NSKNFPTL, LIGRPIIY, and FNDILRRGQLL, with a molecular weight of 723.50, 735.40, 919.48, 943.59, and 1343.76 Da, respectively.

Glutelins derived from oats were purified and hydrolyzed sequentially using alcalase proteases for production of antioxidant peptides. The antioxidant activities of oat glutelin peptides were evaluated using reducing power methods including hydroxyl and 1,1-diphenyl-2-pycrylhydrazyl (DPPH) radical-scavenging assays. The results demonstrated that oats glutelin peptide D-1a exhibited the highest antioxidant activity compared to the other hydrolysates. D-1a was identified to be His–Tyr–Asn–Ala–Pro–Ala–Leu (784.38 Da) by electrospray ionization mass spectrometry (ESI-MS/MS).

Camel milk is a good nutritional source for people living in the arid and urban areas. This study aim to identify ACE-inhibitory peptides from dromedary camel milk produced using Lactobacillus helveticus or Lactobacillus acidophilus. Ten ACE-inhibitory peptides were identified using HPLC-MALDI-TOF MS. L. helveticus strain was found superior in respect to production of ACE-inhibitory peptides, compared with L. acidophilus due to having high proteolytic activity. However, all identified amino acid sequences were corresponding to β-casein of camel milk (Camelus dromedarius). Furthermore, molecular mass of identified peptides were below 1200 Da. Some ACE-inhibitory peptides were found to remain stable for up to 15 d of storage.

Objective: Analyze phylogenetic relationships and molecular mimicry of Cit s 2 and other plant profilins., Methods: Online bioinformatics tools including Basic Local Alignment Search Tool (BLASTP), PRALINE and MEGA were used for multiple alignments and phylogenetic analysis. A 3D-homology model of Cit s 2 was predicted. Models were calculated with MODELLER. The best model was selected with the model scoring option of MAESTRO. Conserved regions between Cit s 2 and other profilins were located on the 3D model and antigenic regions were predicted by ElliPro server (3-5)., Results: Cit s 2 amino acid sequence (Uniprot code:P84177) was compared with other 30 profilins from different allergenic sources. The identity between Cit s 2 and other profilins ranged between 82 and 99%. The highest identity was observed with Cucumis melo (99%) followed by Prunus persica (98%) and Malus domestica (92%). High conserved antigenic regions were observed on the 3D predicted model. Seven lineal and six discontinuous epitopes were found in Cit s 2., Conclusion: High conserved antigenic regions were observed on the 3D predicted model of Cit s 2, which might involve potential cross-reactivity between Cit s 2 and other profilins. Future studies are needed to further analyze these results.

Objective: Conduct an in-silico assessment of potential molecular mimicry between human aquaporins, A. fumigatus , and diverse allergenic sources., Methods: Amino acid sequences of human AQP3 and A. fumigatus aquaporin were compared through multiple alignments with 25 aquaporins from diverse allergenic sources. Phylogenetic analysis and homology-based modeling were executed, and the ElliPro server predicted conserved antigenic regions on 3D structures., Results: Global identity among studied aquaporins was 32.6%, with a specific conserved local region at 71.4%. Five monophyletic clades (A-E) were formed, and Group B displayed the highest identity (95%), including 6 mammalian aquaporins, notably AQP3. A. fumigatus aquaporin exhibited the highest identity with Malassezia sympodialis (35%). Three linear and three discontinuous epitopes were identified in both human and A. fumigatus aquaporins. The Root Mean Square Deviation (RMSD) from overlapping aquaporin structures was 1.006., Conclusion: Identification of potential linear and conformational epitopes on human AQP3 suggests likely molecular mimicry with A. fumigatus aquaporins. High identity in a specific antigenic region indicates potential autoreactivity and a probable antigenic site involved in cross-reactivity. Validation through in vitro and in vivo studies is essential for further understanding and confirmation.

Introduction: Cancer is the second leading cause of death in the United States, surpassed only by cardiovascular disease. However, cancer has now overtaken cardiovascular disease as the main cause of death in 12 countries in Western Europe. The burden of cancer is posing a major challenge to health care systems worldwide and demanding improvements in methods for cancer prevention, diagnosis, and treatment. Alternative and complementary strategies for orthodox surgery, radiotherapy, and chemotherapy need to be developed., Objective: To determine the oncolytic potential of tumor cell-adapted rotavirus in terms of their ability to infect and lysate murine myeloma Sp2/0-Ag14 cells., Materials and Methods: We inoculated rotaviruses Wt1-5, WWM, TRUYO, ECwt-O, and WTEW in Sp2/0-Ag14 cells and we examined their infectious effects by immunocytochemistry, immunofluorescence, flow cytometry, and DNA fragmentation assays., Results: Rotavirus infection involved the participation of some heat shock proteins, of protein disulfide isomerase (PDI), and integrin β3. We detected the accumulation of viral antigens within the virus-inoculated cells and in the culture medium in all the rotavirus isolates examined. The rotavirus-induced cell death mechanism in Sp2/0-Ag14 cells involved changes in cell membrane permeability, chromatin condensation, and DNA fragmentation, which were compatible with cytotoxicity and apoptosis., Conclusions: The ability of the rotavirus isolates Wt1-5, WWM, TRUYO, ECwt-O, and WTEW to infect and cause cell death of Sp2/0-Ag14 cells through mechanisms that are compatible with virus-induced apoptosis makes them potential candidates as oncolytic agents.

Objective The objective of this in silico study was to compare nucleotide and amino acids DENV-2-NS1 sequences isolated from febrile patients, with and without disease severity, from different South American countries. Matherials and Methods A bayesian MCMC phylogenetic analysis was carried out using 28 complete sequences of the gene NS1 of the DENV-2 serotype (1 056 bp), using MrBayes v.3.2.0 software, with the model SYM+G (2.5 million generations). We also carried out a phylogenetic analysis with Neighbor-Joining method (Jukes-Cantor model). In addition, the amino acids sequences were aligned and compared with each other, using Clustal W included in MEGA v.5.2 software. Results In the amino acids sequences associated with bleeding, the most frequent substitution was isoleucine → threonine at posicion 93. These sequences showed a high percentage (94.6 %) of amino acid homology in comparison with the percentage of amino acids homology (74 %) of DENV-2 isolates not associated with bleeding. Five clades were identified that group the vast majority of the DENV-2-NS1 sequences analyzed (19/24; 79.2 %) with posterior probability values greater than or equal to 58 %. Seven sequences (87.5 %) associated with bleeding were phylogenetically related within clades 4 and 5, the posterior probability values were 58 % and 97 %, respectively. Conclusion Neither phylogenetic characteristics nor differences between amino acids of the DENV-2-NS1 sequences studied were found that could be associated directly with severity of the disease.

Background: TJP1 gene encodes a ZO-1 protein that is required for the recruitment of occludins and claudins in tight junction, and is involved in cell polarisation. It has different variations, the frequency of which has been studied in different populations. In Mexico there are no studies of this gene. These are required because their polymorphisms can be used in studies associated with medicine and surgery. Therefore, the aim of this study was to estimate the frequency of alleles and genotypes of rs2291166 gene polymorphism TJP1 in Mexico Mestizos population, and to estimate the conformational effect of an amino acid change., Material and Methods: A total of 473 individuals were included. The rs2291166 polymorphism was identified PASA PCR-7% PAGE, and stained with silver nitrate. The conformational effect of amino acid change was performed in silico, and was carried out with servers ProtPraram Tool and Search Database with Fasta., Results: The most frequent allele in the two populations is the ancestral allele (T). A genotype distribution similar to other populations was found. The polymorphism is in Hardy-Weinberg, p>0.05. Changing aspartate to alanine produced a conformational change., Conclusions: The study reveals a high frequency of the ancestral allele at rs2291166 polymorphism in the Mexican population., (Copyright © 2015 Academia Mexicana de Cirugía A.C. Published by Masson Doyma México S.A. All rights reserved.)

Glucagon-like peptide 1 (GLP-1) is secreted from enteroendocrine L-cells in response to oral nutrient intake and elicits glucose-stimulated insulin secretion while suppressing glucagon secretion. Moreover slows gastric emptying -reducing postprandial glycemic excursions-, reduces body weight, systolic blood pressure and has beneficial effects in the cardiovascular and central nervous systems. Since the 1990s, the efficacy of GLP-1 in reducing blood glucose levels in type 2 diabetes (DM2) was well known. However, GLP-1 should be administered by chronic subcutaneous infusion because of the rapid cleavage by the enzyme dipeptidyl peptidase 4 (DPP-4). Hence, DPP-4 inhibitors -which increase pseudo-physiologically endogenous GLP-1 levels- were developed. In addition, several GLP-1 receptor agonists have been designed to avoid DPP-4-breakdown and/or rapid renal elimination and, therefore, induce a pharmacologic effect in the GLP-1 receptor: short-acting, long-acting, and prolonged-acting GLP-1 analogs. Each class has different structural, pharmacodynamic and clinical properties and could be administered in different therapeutical regimens giving us the opportunity to individualize the therapy of DM2., (Copyright © 2014 Elsevier España, S.L.U. All rights reserved.)

Introduction: The microphthalmia -associated transcription factor ( MITF ) regulates the expression of specific genes and its cardiac expression and function is not known., Objectives: To identify the expression of MITF in hearts and isolated cardiomyocytes from Guinea pigs, to describe morphological changes associated with mRNA interference of MITF and to evaluate their relative changes in expression in isolated cardiomyocytes under ischemic preconditioning., Materials and Methods: The cardiac specific isoform, MITF-H, and relative expression level analysis, was determined by semi-quantitative real time PCR, sequencing and Western blotting. Reduction of mRNA-MITF-H was induced by transduction of specific-MITF-shRNAi interference. The cardiac morphological changes, diameter and number of cardiac fibers were evaluated by direct observation and light microscopy., Results: A cDNA fragment of 281 bp was amplified from heart and isolated ventricular cardiac myocytes. Sequence analysis confirmed the identity of the isoform MITF-H, exon 1. The MITF silencing was associated with an increase in cardiac index (heart weight/body weight vs . 5.46 x 10 -3 vs 4.6 x 10 -3 ) and higher diameter of cardiac fibers (50.2±16 µ m vs 38,7±14,7 µ m p<0.05, n=150). In isolated cardiac myocytes under ischemic preconditioning we observed a higher relative expression compared with that measured in myocytes exposed to normoxia and simulated ischemia (eighty and one hundred times, p <0.05, n = 5). Conclusion. The results suggest that MITF-H isoform may be involved in Guinea pig cardiac hypertrophy, response to stress by ischemia and cardiomyocytes survival.

Background: β-(1,3)(1,6)-D-glucan is fungal cell wall component that has demonstrated immunomodulatory and anti-cancer effects. The (1,3)-β-glucan synthase is one of the main enzymes involved in its biosynthesis., Aims: To design primers to partially amplify and characterize the (1,3)-β-glucan synthase gene and to determine them in Ganoderma lucidum (G. Lucidum) strain CP-132., Methods: The primers were designed on the basis of homologous genes in other fungi. Then, using the PCR technique, primers were tested using DNA extracted from the G. lucidum strain CP-382. Amplified sequences were compared with those from the GenBank., Results: Three primer pairs were designed; all of them produced amplicons of the expected size. The sequences obtained with primer pairs BGS2113UmF and BGS3097UmR, and BGS547UmF and BGS2113UmR matched with 2 sections of the (1,3)-β-glucan synthase gene. The deduced amino acid sequences showed high similarity with homologous genes from other fungi, particularly with those of the Agaricomycetes class., Conclusions: The primer design to partially amplify the (1,3)-β-glucan synthase gene of G. lucidum using sequences from homologous genes was successful. These primers will allow to characterize this important enzyme in a wide group of fungi., (Copyright © 2012 Revista Iberoamericana de Micología. Published by Elsevier Espana. All rights reserved.)

Hereditary alpha-1-antitrypsin (α1-AT) deficiency predisposes to pulmonary emphysema. The objective of this study is to demonstrate the limitations of some laboratory methods used in the study of the deficiency, and which may produce errors in interpretation and detection of uncommon alleles. Two clinical cases are described: the index patient, who had pulmonary emphysema with α1-AT levels less than 12 mg/dL, was erroneously classified as a homozygote of the normal allelic variant PI MM using a rapid genotype method; the mother of the patient, asymptomatic, with low levels (60 mg/dL), was also classified as PI MM. The gene sequencing classified the index patient as a carrier of the PI Clayton null allele and PI Mmalton deficient. The mother was a PI Clayton/PI heterozygote carrier. These results highlight the difficulties in diagnosing the deficiency, as the well as the need to reach a consensus on methods for this study., (Copyright © 2010 SEPAR. Published by Elsevier Espana. All rights reserved.)

In the last years, Enterobacteriaceae such as Klebsiella pneumoniae, Proteus mirabilis and Escherichia coli, have acquired resistance to third-generation cephalosporins (C3G) because of the presence of plasmid-mediated AmpC ß-lactamases. The aim of this work was to detect plasmid AmpC enzymes and to investigate the predominant types in our region. Between March and July 2009, 733 consecutive isolates of Enterobacteriaceae derived from hospitals and outpatient centers were studied. Susceptibility testing was performed by disk diffusion; one P. mirabilis and three E. coli strains showed resistance to cephamycins (cefoxitin) and C3G. An E-test to determine MIC and a synergy test by aminophenylboronic disks were performed. Enzymatic activity against cefoxitin was confirmed by a microbiological assay. A polymerase chain reaction (PCR) for the detection of plasmid-mediated ampC genes of different groups was performed and a 462-bp amplicon was obtained when using primers directed against the CIT group; the obtained sequences were compared to blaCMY-2 sequences, showing 100% identity. The emergence of CMY-2-type plasmid-mediated AmpC ß-lactamases indicated the importance of implementing systematic monitoring of these resistances to avoid potential clinical and epidemiological consequences.

The widespread use of insulin analogues is based not only on the pharmacokinetics of these preparations, which is much closer to the physiology of insulin secretion under normal conditions, but also on their safety and effectiveness. The publication of a possible association between the use of a long-acting insulin analogue (glargine) and breast cancer has caused uneasiness among the medical community regarding the safety of these analogues. The mechanism of increased tumor activity of insulin analogues is explained by the fact that they act through insulin receptors (IR) and insulin-like growth factor-1 (IGF-1R), stimulating cell growth and inhibiting apoptosis. There are two major mechanisms: an increase in the binding time of insulin to IR and increased activation of IGF-1R. Therefore, to evaluate the safety of an analogue, the slower dissociation rate from its insulin receptor must be excluded, as well as the increased affinity for the IGF-1 receptor. This is equivalent to an index of mitogenic/metabolic activity of less than 1. These aspects can only be evaluated through study of cell lines and animal testing, which are reductionist models that cannot always be extrapolated to humans. To date, there are no data to question the safety of insulin analogues in general. However, the results of observational studies and some in vitro studies, suggesting a potential risk of mitogenicity with the administration of glargine, have caused some alarm among the medical community. Until now, there are no data to refute or confirm this risk and, therefore, evaluation of the existing data is crucial to obtain objective information., (Copyright © 2010 SEEN. Published by Elsevier Espana. All rights reserved.)

Introduction: Pseudomonas aeruginosa strains producing metallo-beta-lactamases (MbetaL) are uncommon in Spain. This study describes the characterization of 9 new clonally related multiresistant P. aeruginosa isolates possessing the bla(VIM-2) gene in Cantabria (Northern Spain)., Methods: P. aeruginosa clinical strains (1 per patient) were isolated in the Microbiology Service of Marqués de Valdecilla University Hospital between January 2004 and December 2006. Identification and preliminary susceptibility studies were performed with the MicroScan WalkAway system (Dade Behring, Sacramento, CA) and results were verified by a microdilution reference method., Results: MICs of imipenem and meropenem for the 9 isolates ranged from 32 to 128 and 16 to 64 microg/mL, respectively. Nine isolates had a single Rep-PCR pattern and were intermediate or resistant to ceftazidime, cefepime, gentamicin, tobramycin, amikacin and ciprofloxacin. Eight of the 9 isolates were susceptible to aztreonam. Hydrolysis activity of imipenem in MbetaL-positive isolates ranged from 162+/-18 to 235+/-28 pmol/min/microg protein and was abolished in the presence of 5 mM EDTA. All isolates possessed an integron with genes aac(6')32, bla(VIM-2) and a putative transposase-encoding gene, flanked by the conserved 5'CS and 3'CS regions., Conclusion: In the clinical isolates studied, the presence of MbetaL VIM-2 sufficed to explain their resistance to carbapenems., (Copyright (c) 2008 Elsevier España, S.L. All rights reserved.)

The development of a preventive vaccine against human immunodeficiency virus type-1 (HIV-1) provides hope for control of the pandemic over the coming years. Nevertheless, it is clear that one of the greatest difficulties in achieving this vaccine is the high mutation rate of the virus, which enables it to evade the host's immune response. The production of neutralizing antibodies (NAb) against the HIV-1 envelope proteins is believed to play an important role in controlling the infection and in providing effective protection following vaccination. Several studies have shown that the V1/V2 domain of the HIV-1 gp120 envelope protein is involved in viral tropism during infection, in masking conserved neutralizing epitopes, in the conformational changes occurring after coreceptor binding, and in NAb induction. Nonetheless, this domain has been poorly investigated. However, because the V1/V2 domain is highly glycosylated, numerous studies have determined the influence of carbohydrates on NAb production. The present review focuses on the importance of NAb directed against epitopes of the variable regions, mainly V1/V2, their importance in protecting against HIV-1 infection, and the role these regions play in evading the immune response. Lastly, we will discuss the importance of NAb in the search for an effective vaccine against HIV-1.

The recent approval of the first CCR5 antagonist, Maraviroc (MVC, Celsentri), with specific antiviral activity against R5-tropic virus variants has generated the need for studies to determine the viral tropism in all those patient candidates for starting treatment with this new drug. Although genotyping methods appear to be the most useful tool due to its speed and simplicity, in the case of viral tropism, phenotyping techniques are currently considered the most reliable. In the last few years, different phenotyping assays have been developed to determine the use of the co-receptor. However, the Trofile phenotype assay is currently the one most used for the determination of tropism, since it is the only one that has been clinically validated. Given that the presence of X4- tropic variants in the viral population has been associated with virological failure to MVC, the main challenge of both genotyping and phenotyping tools is to optimise their sensitivity for detecting X4-tropic variants present in a minority of the viral population. At the same time, the correlation between genotyping/phenotyping methods is being evaluated to determine whether genotyping tools can be useful to make therapeutic decisions.

Maraviroc (MVC) is a new antagonist of the CCR5 coreceptor and is the first antiviral compound available that has a cell factor essential for HIV entry as a target. The information available from clinical studies with MVC suggests that the main cause of therapeutic failure is, more than the tropism change, the rapid selection of pre-existing strains with an affinity for CXCR4, not detected by the reference test. A recently developed tropism test with an improved sensitivity will help to detect the minority, but clinically significant, presence of strains that use CXCR4. Evidence of resistance to MVC has been shown in vivo in some patients. The mechanism of this resistance appears to be related to changes in gp120 and mainly in the V3 region which enables the virus to recognise the CCR5-co-receptor bound to the MVC molecule. From a practical point of view, standardised tests are currently unavailable to assess susceptibility to MVC, although in dose-response phenotype tests a maximum percentage inhibition (MPI) < 95% would be indicative of resistance to the compound. Similarly, although some mutations associated with resistance in V3, and other zones of gp120, have been described, this preliminary information suggests different resistance patterns and at the moment, we do not know the canonical mutations to be able to establish genotyping algorithms.

Introduction: The genus Leishmania is divided into two subgenera: Leishmania and Viannia. The two subgenera present several important differences such as the pathology they cause in susceptible hosts, their in vitro growth behavior, their genetic characteristics, and the expression pattern of several proteins, including those of the hydrophilic surface protein family., Objective: To characterize the hydrophilic surface protein family in Leishmania (Viannia) panamensis., Materials and Methods: The hasp genes were amplified in L. (V.) panamensis, using specific primers previously designed to amplify this gene in Leishmania (Leishmania) major. The PCR products were cloned, sequenced, and the sequences analyzed using common bioinformatics tools. Secondly, a serological screening was undertaken with an enzyme-linked immunosorbent assay and Western blot to detect specific antibodies against the hydrophilic surface recombinant protein from L. (L.) major., Results: A copy of a pseudogene was amplified in L. (V.) panamensis which was 60% homologous with the L. (L.) major orthologous gene. Antibodies responded to the hydrophilic surface recombinant proteins only in sera from patients with visceral leishmaniasis [Leishmania (Leishmania) chagasi]., Conclusion: These results suggest the lack of a functional hasp gene in L. (V.) panamensis, suggesting probably the loss of the complete gene family in this species of the Viannia subgenus.

Introduction: The T-cell receptor (TCR)-associated complex, CD3 (d, g, e) and z-chains are essential transmembrane proteins for signal transduction during T cell activation and immune response, as well as during thymocyte development., Objective: This work established the CD3epsilon-chain primary structure for the New World owl monkey Aotus nancymaae., Materials and Methods: Total RNA was isolated from peripheral blood mononuclear cells; CD3epsilon molecule was amplified, cloned and sequenced., Results: The CD3epsilon amino acid sequence was deduced for the owl monkey Aotus nancymaae.> It has an identity for nucleotide and amino acid sequences with the human counterpart of 84% and 76%, respectively. As described in other species, the Aotus CD3-e molecule is very variable in the extracellular region and greatly conserved in the intracellular domain. Even though high variability occurs in the CD3epsilon-extracellular domain, the subregions involved in ectodomain folding are conserved., Conclusions: The primary structure suggested that the Aotus protein has a functional role similar to that of humans, and that the initial T-cell activation steps are also similar. However, the great variation observed in CD3epsilon-extracellular region in humans in contrast to the Aotus (especially in areas that are surface-exposed) indicated that some monoclonal antibodies against the human CD3 complex will not recognize these Aotus determinants.

Introduction: Studies on leptin administration have demonstrated a reversion of insulin resistance, and that leptin produces effects in glucose metabolism., Objective: Changes in the insulin and glucose concentrations in blood plasma was evaluated by intraperitoneal administration of mimetic leptin peptides in Wistar rats fed with high fat diet., Materials and Methods: A control group of rats was defined that were fed with high fat diet and a control group with normal diet. Several treatments groups were fed with high fat diet and subjected to the administration of seven different mimetic leptin peptides, each one administered in four different concentrations. During the peptide administration the glucose concentrations were quantified and at the end the insulin concentrations., Results: The average insulin concentrations in the control groups were similar; however, hyperinsulinemia was observed in the groups to which we administered the peptide denominated 83 at doses of 10 mg/kg and 20 mg/kg of body weight. All the treatment groups except the peptide denominated with the code 80 showed diminished glucose levels even in the cases without hyperglycemia. The greatest effect was observed with the peptide 116-130 of the mouse leptin and its human homolog, although without statistical differences with the other treatments., Conclusion: Lectin peptides have no effect on the insulin plasma concentrations; however, an effect is evident in glucose levels. Additional research will be required to determine if leptin mimetic peptides influence the glucose metabolism or the expression, secretion, signaling mechanism and regulation of insulin.

Introduction: McArdle's disease (glycogenoses type V) is a common metabolic myopathy caused by deficient myophosphorylase activity. The disease is due to mutations in the myophosphorylase (PYGM) gene and is present in a large number of countries., Case Report: A 13-year-old male who suffered an episode of muscle pain and offered increased levels of creatinkinase in plasma, myoglobinuria and mild weakness of the proximal muscles, after short but vigorous exercise. The patient was born in Ecuador and was adopted by a Spanish family. The myophosphorylase gene was analysed completely and the patient was found to be a carrier of a missense mutation, a homozygous change where a G is replaced by an A in exon 11, changing a valine for a methionine in codon 456 (V456M). The mutation described above affects an amino acid that is conserved in the enzyme and which was not present in the control population that was studied., Conclusions: These findings show the presence of McArdle's disease in several ethnic groups and confirm that the ethnic origin of the patient is important when it comes to deciding what mutations should be analysed first in molecular diagnosis studies.

The epidemic characteristics of type 2 diabetes mellitus (DM) pose a formidable challenge in terms of healthcare, given the tremendous impact it has on the healthcare resources needed not only to treat it, but also to prevent and treat the associated cardiovascular complications. This makes up the number 1 cause of DM-associated morbidity-mortality in addition to its social and personal impact. We currently have a growing number of available treatment tools that make it possible to achieve the target glycemic control in most of our patients, albeit unfortunately, only temporarily in a good many of them, because of the progressive nature of the disease. Furthermore, current therapy often entails undesirable effects, such as weight gain or the emergence of hypoglycemias that limit their optimization. Recently, a new class of drugs has been incorporated into the treatment of DM - incretin mimetics. These new drugs act in very much the same way as the intestinal hormones that are naturally secreted following the intake of nutrients, called incretins (e.g., glucagon like peptide-1 [GLP-1]), with the added advantage that these molecules are resistant to enzymatic degradation by the DPP-IV enzyme. This provides them with a half-life that makes ambulatory treatment possible, unlike natural incretins whose half-life is too short to make them viable as treatment. The incretin mimetics bind to GLP-1 receptors, increasing glucose-dependent secretion of insulin and decreasing glucose-dependent posprandial secretion of glucagon, slowing gastric emptying, and reducing food intake. All these mechanisms have a significant impact on glucose homeostasis and a beneficial effect on body weight. Moreover, studies in experimental models suggest that these new molecules might have a promising effect on pancreatic beta cell function and mass. Exenatide is the first incretin mimetic available to date. Efficacy and safety data of this drug show it as a therapeutic option for the treatment of type 2 DM.

The toll-like receptors are an essential component of the innate and adaptive immune response. They are responsible for the recognition of different pathogens agents and trigger responses directed at eliminating the pathogens as well as the development of immunological long-term memory. During viral infections, several different toll-like receptors are activated. These generally induce a protective immune response, but at the same time, can also be part of the pathogenic mechanisms of the viral infection. One of the viral infections in which toll-like receptors participate is the HIV-1 infection. Here, several receptors are activated to develop antiviral responses mediated by interferon type I; however virus replication and spreading dissemination are also favoured by signals derived from stimulation of the toll-like receptors. Individuals co-infected with opportunistic microorganisms are particularly affected, promoting the progression of HIV-1 infection. An integral understanding of the behavior of toll-like receptors during viral infections will allow the design of prophylactic and/or therapeutic strategies, based on the modulation of the expression and function of these receptors. Agonists of these receptors can be used effectively to control these viral infections.

P450 aromatase (P450Aro), involved in androgen to estrogen conversion, is encoded by the CYP19 gene. P450Aro c655G>A mutation described in heterozygous form in a girl and in homozygous form in an adult male with P450Aro deficiency results in an aberrant splicing due to disruption of a donor splice site. A truncated inactive protein would be expected if intron5 is retained. Surprisingly, the girl described with this mutation showed spontaneous breast development and pubertal estradiol (E2) levels suggesting residual P450Aro activity (AA). Formerly, we postulate the in frame E5 skipping as a consequence of this mutation generating a protein with some degree of activity. When P450Aro mRNA expression was analysed from patient's lymphocytes, an aberrant spliced mRNA lacking E5 (-E5mRNA) was detected, suggesting an association between E5 skipping and the presence of the mutation. Splicing assays in Y1 cells confirmed this association. -Ex5 cDNA expression in Y1 cells resulted in an inactive protein that could not explain patient's phenotype. Exon 5 might be predicted as a poorly defined exon suggesting a susceptibility to splicing mutations and physiological alternative splicing (AS) events. Therefore, -Ex5mRNA was assessed as a natural occurring alternative transcript in normal human steroidogenic tissues. As P450Aro -E5mRNA expression was detected in human term placenta, prepubertal testis and prepubertal adrenal, we might speculate that AS of P450Aro coding region would occur in humans and would be involved in the complex AA regulation. Furthermore, tissue specific regulation of AS might suggest low expression of +E5mRNA from the c655G>A allele explaining residual AA evidenced in the affected girl.

Infection by the hepatitis B (HBV) and C (HCV) viruses is a major cause of morbidity and mortality world-wide. The clinical outcomes of infection by these viruses (e.g., chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma) depend on several factors related to the host and the viral agent. Among the latter, factors associated with the response to current antiviral therapies, such as the emergence of resistance mutants and the genotype responsible for the infection, are gaining increasing importance. As has been established for human immunodeficiency virus (HIV), the presence of resistance mutations in the viral polymerase constitutes the main problem for treating HBV infection with approved drugs and those recently applied. Methods have been developed to detect these mutations, as well as algorithms to predict the response to treatment. The outcome of treatment for HCV infection is highly influenced by the viral genotype, however, and our understanding of the molecular basis for the response to interferon in these patients has grown considerably in recent years.

Background: Creutzfeldt-Jakob disease (CJD) is a form of transmissible spongiform encephalopathy, in which a prion protein (PrP Sc) accumulates in the brain of affected individuals. Chile has a prevalence of CJD that is more than twice than in the rest of the world and has the highest rate of familial forms. These later forms are associated with the heterozygocity of codon 200 of PrP protein gene., Aim: To search susceptibility genetic markers of CJD in members of families affected by CJD., Material and Methods: A blood sample was obtained from 50 individuals pertaining to four families affected by CJD. DNA from peripheral mononuclear cells was amplified by polymerase chain reaction and sequenced for the gene that codifies PrP protein., Results: In family A, 21 of 23 members were homozygotes for codon 129 (Met/Met) and eight were simultaneously heterozygotes for codon 200 (Glu/Lys). In family B, six of nine members were homozygotes for codon 129, five were heterozygotes for codon 200 and four had both mutations. In family C, the four analyzed subjects were homozygotes for codon 129 and two were simultaneously heterozygotes for codon 200. In family D, nine of 14 members were homozygotes for codon 129 and two were simultaneously homozygotes for codon 200. No family had polymorphisms for codon 219., Conclusions: Thirty two percent of analyzed subjects were homozygotes for codon 129 and heterozygotes for codon 200, condition that defines the genetic susceptibility to acquire CJD. The dominant tendency of these genotypes could explain the higher incidence of CJF in Chile.

Introduction and Development: Current animal models for Alzheimer's research include transgenic mice that express a mutant form of human beta-amyloid precursor protein (APP). However, the mutant mice with the human APP transgene also have their own endogenous APP gene, which may interfere with APP processing to generate beta-amyloid peptide., Conclusion: By genetic and immunochemical analyses, our laboratory has discovered that there are animals in the nature, the chick embryo and the dog in particular, which may be better experimental models than the transgenic mice, because they contain the same machinery as humans to process APP and they are easier to access, manipulate or explore their neurology. These species may be natural experimental models to study the cell biology of Alzheimer's APP and potential assay systems for drugs used to regulate beta-amyloid production as well as for the assay of new therapeutic strategies against so devasting disease.

The plasma kallikrein-kinin system (KKS) participates in the pathogenesis of inflammatory reactions involved in cellular injury, coagulation, fibrinolysis, kinin formation, complement activation, cytokine secretion and release of proteases. It has been shown that KKS activation in the systemic inflammatory response syndrome results in decrease of its component plasma proteins. Similar changes have been documented in diabetes, sepsis, children with vasculitis, allograft rejection, disseminated intravascular coagulation, patients with recurrent pregnancy losses, hereditary angioedema, adult respiratory distress syndrome and coronary artery disease. Direct involvement of the KKS in the pathogenesis of experimental acute arthritis and acute and chronic enterocolitis has been documented by previous studies from our laboratory using experimental animal models. It has been found that in HK deficient Lewis rats, experimental IBD was much less severe. We showed a genetic difference in kininogen structure between resistant Buffalo and susceptible Lewis rats, which results in accelerated cleavage of HK and it is responsible for the susceptibility to the inflammatory process in the Lewis rats. It has been demostrated that therapy with a specific plasma kallikrein inhibitor (P8720) modulated the experimental enterocolitis, arthritis and systemic inflammation. Furthermore, it has been shown that a bradykinin 2 receptor (B2R) antagonist attenuates the inflammatory changes in the same animal model. We have showed that a monoclonal antibody targeting HK decreases angiogenesis and arrests tumor growth in a syngeneic animal model. In summary, these results indicate that the plasma KKS plays a central role in the pathogenesis of chronic intestinal inflammation, arthritis and angiogenesis.

The plasmidic stability of methyltrophic yeast Pichia pastoris expressing the recombinant protein E of dengue virus 4 was analyzed. To this end, the number of generations from the growth process in petri plaque to the propagation in zaranda was estimated, as well as the fermentation process. Besides, in the selected colonies the integration pattern was determined by Dot-Blot and neuclotide sequence of the gene E of dengue virus 4. This study allowed to prove the conservation and integrity of the aminoacid sequence of protein E, despite the genetic changes produced by molecular yeast mechanisms. On the other hand, it was also part of the control and checking of the primary bank of yeast cells that contains the gene of interest used at present in the process of expression of protein E of dengue virus 4.

Lactoferrin (Lf) is an iron binding multifunctional glycoprotein that is present in several mucosal secretions like milk, tears and saliva. Lf is also an abundant component of the specific granules of neutrophils and can be released into the serum upon neutrophil degranulation. One of the functions of this protein is the transport of metals, but it is also an important component of the non-specific immune system. Human and bovine Lfs display a broad antimicrobial spectrum against Gram positive and Gram negative bacteria, fungi and several viruses. While the iron-binding properties were originally believed to be solely responsible for the host defense properties ascribed to lactoferrin, it is now known that other mechanisms contribute to the antimicrobial role of this glycoprotein. This review gives an overview of the knowledge of these mechanisms and the potential clinical applications of Lf against infections

Introduction: The task of cloning the genes whose products are involved in the organisation and functioning of the nerve centres that enable language tasks to be executed must necessarily start with the identification and the cognitive, linguistic, neuroanatomical and neurophysiological analysis of individuals with hereditary (specific) language impairment (SLI)., Development: The first of these genes to be characterised in this way--a gene called FOXP2--codes for a regulating factor that acts as a transcriptional repressor in the central nervous system. It is expressed in neuronal populations mainly situated in the basal ganglia, but also in the cortex, cerebellum and the thalamus, which are presumably involved in the development and/or functioning of the thalamic-cortical-striatal circuits associated with motor planning and learning. The protein FOXP2 shows several structural patterns that, when altered in other proteins, also give rise to different disorders in the central nervous system. The pattern of expression of the gene is preserved phylogenetically, although this does not happen in the case of the pattern of mRNA maturation. In individuals with a mutated version of FOXP2, morphological and functional anomalies are detected in those areas in which the gene is expressed. These abnormalities can be correlated satisfactorily with the phenotypic characteristics of the disorder, which are at the same time of both a motor and linguistic nature., Conclusions: The fact that other variations of SLI are not linked to the FOXP2 gene raises the need for further research into the genetic bases of the disorder, while also suggesting that it would be advisable to reassess the phenotypic scope of the variant associated to the mutation of this gene.

Eukaryotic antibiotic peptides are key components of innate immunity. They act as a first barrier against invading pathogens. Expectations about their clinical use have been raised as they are active against a wide range of pathogens, and unlikely to induce resistance. Both characteristics are related to their lethal mechanism, based on interaction with anionic phospholipids in the outer facet of the cytoplasmic membrane of the pathogens, leading to permeabilization. This review will especially focus on antibiotic peptides of human origin. Their mechanism of action, strategies of pathogen resistance, and role in activities other than microbicidal effect will be described. Practical applications and prospects of future use in anti-infectious therapy will also be discussed.

The serologic diagnosis of human immunodeficiency virus (HIV) infection is currently done by detecting the presence of antibodies against the different antigenic viral proteins through immunoassays and later confirmation by Western blot. Several types of antigens can be used in immunoassays, but recombinant proteins and synthetic peptides are the most frequently used. In this paper, peptides mimicking antigenic regions from p24 (region 196-224), gp41 (region 600-614) and gp120 (region 303-338, Loop V3) proteins of HIV-1 have been used as antigens in an enzyme-linked immunosorbent assay and their reactivity was screened against a panel of positive and negative sera. Six antigenic mixtures containing different amounts of each peptide were prepared, and the one consisting of 1 microgram of gp41-15, 0.5 microgram of p24-1 and 0.5 microgram of gp120-1 per well has shown the best performance to differentiate positive and negative serum samples, with sensitivity and specificity values of 99.18% and 100%, respectively. Considering the potential utilization of this system for screening of HIV infection, it would be relevant to evaluate the additional incorporation of sequences derived from Argentine local circulating viral variants to improve the diagnostic sensitivity of the assay, allowing the development of an ELISA based on specific viral sequences.

Background: The resistance of Shigella flexneri to antimicrobial agents can be associated to the presence of integrons that may contain and express antimicrobial resistance gene cassettes., Aim: To study antimicrobial resistance and the presence of integrons and antimicrobial gene cassettes in Shigella flexneri strains., Material and Methods: In vitro susceptibility to 27 antimicrobials was studied in twenty four Shigella flexneri strains isolated from stools. The presence of integrons class 1, 2 and 3 and antimicrobial resistance gene cassettes was investigated by polymerase chain reaction (PCR) using specific primers for each gene., Results: Most strains were resistant to one of the following antimicrobials: ampicillin, sulphonamide, trimethoprim, tetracycline, streptomycin, sulfamethoxazole-trimethoprim or chloramphenicol. Twenty nine percent were simultaneously resistant to all these antimicrobials. Integrons class 1 and 2 were found in 19 strains (79%). Class 3 integrons were not found. Gene cassettes dfrA1 and ant(3")I were associated to integrons class 2 in most strains (15/20, 75%). Genes cat, tetB and blarTEM were detected in 18/24 (75%), 7/24 (29%) and 4/24 (17%) of the strains, respectively and were not associated to any of the studied integrons. Genes that codify enzymes AAC(6')Ib and APH(3')VI were not detected in any strain., Conclusions: The high frequency of integrons found in the studied strains, could partly explain the increasing antimicrobial resistance of Shigella flexneri strains, isolated in Chile.

Three urban rabies outbreaks have been reported in Colombia during the last two decades, one of which is ongoing in the Caribbean region (northern Colombia). The earlier outbreaks occurred almost simultaneously in Arauca (eastern Colombia) and in the Central region, ending in 1997. Phylogenetic relationships among rabies viruses isolated from the three areas were based on a comparison of cDNA fragments coding for the endodomain of protein G and a fragment of L protein obtained by RT-PCR. The sequenced amplicons which included the G-L intergenic region contained 902 base pairs. Phylogenetic analysis showed three distinct groups of viruses. Colombian genetic variant I viruses were isolated only from Arauca and the Central region, but are now apparently extinct. Colombian genetic variant II viruses were isolated in the Caribbean region and are still being transmitted in that area. The third group of bat rabies variants were isolated from two insectivorous bats, three domestic dogs and a human. This associates bat rabies virus with rabies in Colombian dogs and humans, and indicates bats to be a rabies reservoir of public health significance.

Introduction: The neuregulins are a family of factors that perform important functions during the development of the nervous system, neuromuscular junction and heart. These factors are also involved in nervous system disorders, and in the generation and progression of tumors., Development: There are four genes and many isoforms which share a similar molecular structure. The neuregulins are differentially expressed and bind with different affinities to specific combinations of ErbB receptors. This level of complexity is directing numerous researching in order to understand the molecular mechanisms that regulate a specific pathway., Conclusion: Neuregulin ErbB receptor complexes activate specific intracellular pathways that culminate in very different fates: differentiation or proliferation.

We present a clinical case of antiretroviral treatment failure with appearance of mutations demonstrated by genotyping. We also show the evolution of the pattern of mutations that confers resistance to protease and reverse transcriptase inhibitors along with changes in the scheme of drugs indicated to the patient. A deletion was found in codon 67 of the TR gen, along with a novel resistance model to AZT pointing out the benefits of the detection of antiviral resistance by sequencing (genotyping).

Hereditary nonpolyposis colorectal cancer (NHPCC) is the most common form of inherited colon cancer and one of the most frequent autosomal dominant disorders. HNPCC presents an early onset of colorectal cancer (< 50 years), proximal localization of the colonic tumors, and high risk of developing multiple primary colorectal tumors as well as extracolonic tumors. This disease is caused by mutations in at least four DNA mismatch repair genes, (hMSH2, hMLH1, hPMS1 and hPMS2) and estimations indicate that it affects 1:200-1:2,000 people in the Western populations. The identification of the genes responsible for HNPCC has prompted the search for mutations in affected individuals. DNA from an affected member of a family was sent to a Dutch HNPCC Diagnosis Centre. This Centre reported a germinal mutation, which introduces a premature stopcodon and causes the production of a truncated protein. This particular mutation has not been previously registered in the database of mutations related to this disease. After the identification of the mutation in the index patient, we have developed a quick and efficient procedure for detecting mutations in the rest of the family. The methodology is based on the amplification of the exon 13 in the hMSH2 gene using a forward primer that abuts the mutation site and introduces the cutting sequence of the enzyme Haelll++ only in the wild type allele. At present, seventeen members of the family have been diagnosed and nine have been found to be affected. The methodology is simple, specific, sensitive, inexpensive and applicable in low complexity laboratories.

Background: Most of the studies of HIV-1 infection in South America have been limited to Brazil and little is known about the viral variants that are causing disease elsewhere in the continent., Aim: To determine the characteristics of the viral variants present in Chile as well as patterns of viral transmission., Material and Methods: Viral sequences were obtained from 21 HIV-1 infected people from Santiago, Chile who were infected either via sexual contact or intravenous drug use. Cloned sequences obtained from both the third variable and conserved regions of the envelope as well as the viral protease were evaluated., Results: We found only clade B subtype viruses in Santiago. An evaluation of the envelope gene revealed no evidence that the sequences were monophyletic by risk group. A number of the protease sequences were predicted to encode amino acid substitutions commonly found during selection for protease inhibitor resistance., Conclusions: The HIV-1 strains studied in Chile, belong to the subtype B. There is no molecular evidence of separate introductions of the virus into the different risk groups. A number of substitutions in the protease gene that may confer resistance to protease inhibitors were found in patients with no previous exposure to this class of drugs.

Cruzipain is the major cysteine proteinase present in Trypanosoma cruzi, the parasite causing the American Trypanosomiasis, Chagas disease. The enzyme is encoded by a high number of genes (up to 130 in the Tul 2 stock) placed in head-to-tail tandems, and located in two to four chromosomes. The simultaneous expression of several different genes results in the production of a complex mixture of isoforms. Those known as a group as "cruzipain 1" differ essentially at the level of the C-terminal domain, in their amino-acid sequence and in their type of N-glycosylation. The existence of a more distantly related cysteine proteinase, "cruzipain 2", has been demonstrated; it differs markedly, particularly at the level of the catalytic moiety.