Publications by authors named "Marcela Medina"

The association between dairy products consumption in adults and the likelihood of type 2 diabetes mellitus (T2DM) has been described, but more information on the adolescent population is needed. This nationally representative, cross-sectional school-based study aimed to describe the consumption of dairy products and their subtypes and to evaluate their association with prediabetes and T2DM in adolescents. The Study of Cardiovascular Risks in Adolescents (ERICA) includes adolescents aged 12-17 years.

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Viral respiratory infections caused by RNA viruses are one of the most important diseases around the world. The aim of this work was to study whether the nasal administration of non-viable Lactobacillus casei (LcM) was able to enhance respiratory antiviral defenses in young mice challenged with Poly I:C. Three-week-old BALB/c mice were nasally challenged with Poly I:C, used to mimic the pro-inflammatory state of lung infections caused by RNA viruses.

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Given that the cadmium (Cd) toxicity could be due to its interference with the calcium (Ca) homeostasis, the aim of this work was to study the effect of Cd over the presence, distribution and volume density (Vv) of Ca and Ca-ATPase in the secretory cells of the pars preconvoluta (PPC) and the pars convoluta (pc) in . The severe effect of the xenobiotic (CdCl 2.5 mg/kg) in sexually matured females was evaluated.

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Background: Polyinosinic:polycytidylic acid (Poly-IC) has been used as a viral stimulus to mimic in vivo and in vitro infection induced by some viruses.

Objective: To determine whether non-viable Lactobacillus casei CRL431 (LcM) can modulate the immune response induced by Poly I:C in co-culture models of peripheral blood mononuclear cells (PBMC) and A549 cells.

Methods: T and NK cell activation was evaluated by flow cytometry and levels of TNF-α, IFN-γ, IL-10, IL-29, and IL-17 by ELISA.

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: The current study aims at evaluating the effect of the oral administration of Lactobacillus casei CERELA (CRL) 431 on parameters implicated in inflammation-coagulation interaction using a model of acute inflammation induced by lipopolysaccharide (LPS) in mice. Six-week-old Balb/c mice were treated with L. casei for 5 consecutive days.

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The cadmium (Cd) concentration in the environment has increased as a consequence of anthropogenic activity. The objective of this study was to determine early signs of Cd toxicity in testes and sperm as possible biomarkers. The dose orally administered to Wistar rats was within the range where chronic toxicity can appear.

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The intestinal microbiota would be implicated in pathology associated with celiac disease caused by an abnormal immune system reaction against gluten present in cereal grains. The objectives of this work were to detect through basic methods the changes in the composition of the most common genera of bacteria from the intestinal microbiota of symptom-free celiac disease children with a gluten-free diet compared with healthy children from Tucumán and to select lactobacilli (Lb) strains with probiotic potential from the feces of healthy children. Results demonstrated that the feces of celiac children with a gluten-free diet showed significantly lower counts of Lb (P < 0.

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Streptococcus pneumoniae is a highly important respiratory pathogen that causes infections in children, elderly people and immunocompromised people around the world. Pneumococcal vaccines licensed did not reach to eradicate the pneumococcal infection. In a previous study was demonstrated the effectiveness of a nasal experimental vaccine that consisted in a pneumococcal protective protein A (PppA) co-administrated with heat-killed-Lactobacillus casei (LcM), in mice model of respiratory pneumococcal challenge.

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In the present study we analysed the ultrastructural characteristics of the oviductal mucosa of Leptodactylus chaquensis during the preovulatory period and immediately after ovulation. Epithelial secretory cells, ciliated cells, basal cells and glandular secretory cells are described. During the preovulatory period, the oviduct exhibits its maximum degree of development at both the epithelial and the glandular levels, with numerous secretory cells that contain a large number of secretory granules whose contents are released into the oviductal lumen by apocrine and exocytotic secretory processes.

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The presence of a calcium pump, calbindin D-28KD, and calmodulin in the secretory cells (SC) of the oviductal pars convoluta (PC) of Rhinella arenarum was established for the first time in amphibians using immunohistochemical techniques. Marked variations were observed in the localization and degree of expression of these proteins according to the duct segment and the period of the sexual cycle analyzed. During the preovulatory and ovulatory periods the calcium pump colocalized with calbindin D-28KD can be seen mainly in the apical border of the SC, which are located in the first zones of PC and synthesize and secrete the components of the inner jelly coat layers.

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In the present study we describe for the first time in anuran amphibians the histological and ultrastructural characteristics of innervation in the female reproductive organs. The observations in Rhinella arenarum revealed the presence of nerve fibers located predominantly in the ovarian hilium and in the oviduct wall. In both organs the nerves fibers are placed near blood vessels and smooth muscles fibers.

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This work analyzes the humoral and cellular immune responses induced by live (LcV) and heat-killed (LcM) Lactobacillus casei associated with the pneumococcal antigen (P-Ag) at the nasopharynx level, considering nasal-associated lymphoid tissue (NALT) as the primary inductive site of the mucosal immune system, and lung and blood as effector sites. Levels of P-Ag IgA and IgG antibodies, main types of B and T cells, and cytokines in mucosal and systemic compartments were evaluated. The results showed that both LcM+P-Ag and LcV+P-Ag vaccines effectively induced IgA and IgG anti-P-Ag Abs in the upper and lower respiratory tract and plasma.

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Introduction: Knowledge about the prevalence and distribution of human papillomavirus (HPV) genotypes in cervical premalignant and malignant lesions is crucial to guide development of clinical management strategies and prophylactic vaccines. The aim of this study was to determine HPV genotype-specific prevalence and distribution in an underserved cohort of Latino women.

Materials And Methods: From December 2009 to April 2011, 808 SurePath cervicovaginal specimens were collected from women who were referred from charity clinics for abnormal Papanicolaou tests.

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In amphibians, the components of the jelly coats that surround the oocytes at the time of fertilization and coordinate gamete interaction are secreted by the oviduct. We analysed the histological variations in the mucosa of the oviductal pars convoluta (PC) of Rhinella arenarum during the reproductive cycle and its relationship with secretion. During the preovulatory period, the mucosa reaches a high degree of morphological and functional development, with a large number of epithelial (ESC) and glandular secretory cells (GSC) loaded with contents that are secreted into the oviductal lumen.

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The organization and the histological characteristics of Leptodactylus chaquensis testis throughout the reproductive cycle were analyzed in the presented study. Gonads of adult males, processed with routine techniques for optical microscopy, revealed that during the reproductive period the seminiferous tubules were characterized by presentation of a large number of cysts, germ cells at the same maturation stage supported by Sertoli cells. All the germ line cells were also present in the postreproductive period and maintained their morphological characteristics.

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This study was to determine the lethal dose 50 (LD(50)) of CdCl(2) in adult Rhinella arenarum and analyzed the effect of two sublethal doses (0.5 and 5 mg/kg) of the xenobiotic in gonads. The 48 h LD(50) were 50.

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The present study was carried out to analyze the fertilization-supporting activity of Rhinella arenarum egg-jelly components. Spermatozoa were treated with diffusible factor (DF) constituted by the components released from the jelly coat into deionized water or with full jelly (FJ) containing all the components secreted by the oviductal pars convoluta (PC) during the transit of the oocytes through the duct, or with washed jelly (WJ) constituted only by structural components. Both jellies were solubilized by ultraviolet irradiation.

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Background: At present, available pneumococcal vaccines have failed to eradicate infections caused by S. pneumoniae. Search for effective vaccine continues and some serotype independent pneumococcal proteins are considered as candidates for the design of new vaccines, especially a mucosal vaccine, since pneumococci enter the body through mucosal surfaces.

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Most studies of Lactococcus lactis as delivery vehicles of pneumococcal antigens are focused on the effectiveness of mucosal recombinant vaccines against Streptococcus pneumoniae in animal models. At present, there are three types of pneumococcal vaccines: capsular polysaccharide pneumococcal vaccines (PPV), protein-polysaccharide conjugate pneumococcal vaccines (PCV) and protein-based pneumococcal vaccines (PBPV). Only PPV and PCV have been licensed.

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Background/purpose: Oral immunization with Lactococcus lactis PppA (LPA+), a recombinant strain that is able to express the pneumococcal protective protein A, can improve the resistance to respiratory challenge with Streptococcus pneumoniae in adult mice. In this study, we investigated whether oral immunization protocols using LPA+ are able to protect young mice against pneumococcal respiratory infection.

Methods: Young mice (aged, 3 weeks) were immunized orally with LPA+ for 5 consecutive days.

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Background: Coeliac disease is a chronic intestinal inflammatory disorder due to an aberrant immune response to dietary gluten proteins in genetically predisposed individuals. Mucosal immune response through IgA secretion constitutes a first line of defence responsible for neutralizing noxious antigens and pathogens. The aim of this study was the characterization of the relationships between immunoglobulin-coated bacteria and bacterial composition of faeces of coeliac disease (CD) patients, untreated and treated with a gluten-free diet (GFD) and healthy controls.

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The role of monovalent (Na+, K+) and divalent (Ca2+, Mg2+) cations in Bufo arenarum fertilization was analysed. Our results showed that the highest fertilization percentages were obtained when strings of uterine oocytes (UO) were inseminated. Under these conditions, full jelly (FJ), which represents the jelly coats surrounding the oocytes at the time of deposition, contained 68.

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SummaryBufo arenarum oocytes are oviposited surrounded by jelly coats, one component of the extracellular matrix required for fertilization. The secretion, released to the oviductal lumen, was analysed by SDS-PAGE. The coomassie blue staining evidenced an electrophoretic pattern with molecules ranging between 300 and 19 kDa that showed variations in their secretion profiles during the sexual cycle.

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The localization of calcium and Ca-ATPase activity in Bufo arenarum oocytes was investigated by ultracytochemical techniques during progesterone-induced nuclear maturation, under in vitro conditions. No Ca2+ deposits were detected in either control oocytes or progesterone-treated ones for 1-2 h. At the time when nuclear migration started, electron dense deposits of Ca2+ were visible in vesicles, endoplasmic reticulum cisternae and in the space between the annulate lamellae membranes.

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Background: Pre-term birth is a world wide health problem, and although fetal fibronectin (fFN) testing has proven its clinical utility in developed countries, this remains to be determined in the developing world.

Objective: To evaluate the clinical utility of fFN in predicting pre-term birth in a low socio-economic, non-profit hospital setting.

Study Design: In this observational study, pregnant women < 37 completed weeks with symptoms suggestive of threatened pre-term labour (painful regular contractions and cervical modifications) were tested with the fFN test, admitted for management and subsequently followed up every 2 weeks until the end of gestation.

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