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Abstract: Neisseria meningitidis is the causal agent for meningitis and meningococcemia. This research was performed to phenotypically analyze invasive strains of N. meningitidis isolated in Cumana, State of Sucre. The study included all strains identified as N. meningitidis isolated in the bacteriology laboratory at the University Hospital “Antonio Patricio de Alcalá,” during the years 2009-2010, coming from cerebrospinal fluid (CSF) samples and blood cultures. For each isolate, the antimicrobial susceptibility and respective serogroup were determined. During the period of study, 10 strains were analyzed, of which 5 came from CSF. The antimicrobial susceptibility test revealed that the strains showed sensitivity to penicillin, cefotaxime, meropenem, rifampicin, ciprofloxacin and chloramphenicol; they were resistant only to trimethoprim/ sulfamethoxazole. Serogroup B was the most frequent (8 strains); one case of serogroup Y was isolated. Regarding the patient’s ages, of the 10 strains, 8 were found in pediatric patients. This is the first study about strains of N. meningitidis isolated in Cumaná, so it is essential that permanent research regarding the strains isolated in the area is carried out for monitoring purposes, mainly in terms of antimicrobial susceptibility and the circulating serogroups. Resumen: Neisseria meningitidis es agente causal de meningitis y meningococcemia. Se realizó la presente investigación a fin de analizar fenotípicamente las cepas invasivas de N. meningitidis aisladas en Cumaná, estado Sucre. Se incluyó el total de cepas identificadas como N. meningitidis en el laboratorio de bacteriología del Hospital Universitario “Antonio Patricio de Alcalá”, durante los años 2009-2010; provenientes de muestras de líquido cefalorraquídeo (LCR) y sangre (hemocultivos). A cada aislamiento se le determinó la susceptibilidad antimicrobiana y el serogrupo respectivo. Durante el período en estudio se analizaron 10 cepas, de las cuales 5 provenían de LCR. El ensayo de susceptibilidad antimicrobiana reveló que las cepas presentaban sensibilidad a penicilina, cefotaxima, meropenem, rifampicina, ciprofloxacina y cloranfenicol siendo sólo resistentes al trimetoprim/sulfametoxazol. El serogrupo más frecuente fue el B (8 cepas), aislándose un caso de serogrupo Y. Respecto al grupo etario de los pacientes, de las 10 cepas, 8 provenían de pacientes pediátricos. Este es el primer estudio con cepas de N. meningitidis aisladas en Cumaná, por lo que se hace imprescindible el análisis permanente de las cepas aisladas en la zona, con fines de monitoreo, principalmente, de la susceptibilidad antimicrobiana y los serogrupos circulantes.

It is widely recognized that periodontal disease is an inflammatory entity of infectious origin, in which the immune activation of the host leads to the destruction of the supporting tissues of the tooth. Periodontal pathogenic bacteria like Porphyromonas gingivalis , that belongs to the complex net of oral microflora, exhibits a toxicogenic potential by releasing endotoxins, which are the lipopolysaccharide component (LPS) available in the outer cell wall of Gram-negative bacteria. Endotoxins are released into the tissues causing damage after the cell is lysed. There are three well-defined regions in the LPS: one of them, the lipid A, has a lipidic nature, and the other two, the Core and the O-antigen, have a glycosidic nature, all of them with independent and synergistic functions. Lipid A is the "bioactive center" of LPS, responsible for its toxicity, and shows great variability along bacteria. In general, endotoxins have specific receptors at the cells, causing a wide immunoinflammatory response by inducing the release of pro-inflammatory cytokines and the production of matrix metalloproteinases. This response is not coordinated, favoring the dissemination of LPS through blood vessels, as well as binding mainly to Toll-like receptor 4 (TLR4) expressed in the host cells, leading to the destruction of the tissues and the detrimental effect in some systemic pathologies. Lipid A can also act as a TLRs antagonist eliciting immune deregulation. Although bacterial endotoxins have been extensively studied clinically and in a laboratory, their effects on the oral cavity and particularly on periodontium deserve special attention since they affect the connective tissue that supports the tooth, and can be linked to advanced medical conditions. This review addresses the distribution of endotoxins associated with periodontal pathogenic bacteria and its relationship with systemic diseases, as well as the effect of some therapeutic alternatives.

The objective of this study was to develop zein-casein-lysine nanoparticles to modulate the intestinal permeability of ferulic acid (FA), a bioactive compound with proven antioxidant properties. The nanoparticles were obtained by a liquid-liquid dispersion method and were characterized in terms of mean size, polydispersity index, zeta potential, association efficiency (AE), in vitro drug release, x-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). The in vitro intestinal permeability of nanoparticles was evaluated through Caco-2 and Caco-2/HT29-MTX monoculture and co-culture models, respectively. Nanoparticles presented a mean size of 199 nm and zeta potential of -26 mV. The AE of FA was 23% evaluated by high-performance liquid chromatography (HPLC). XRD showed amorphization of FA after association and FT-IR showed no changes in chemical structures of the compounds after nanoencapsulation. The cytotoxicity assays demonstrated that multicomposite nanoparticles presented a safe profile against Caco-2 and HT29-MTX cells. In the in vitro permeability assay, free FA exhibited higher permeability compared to FA-loaded nanoparticles, possibly due to prolonged FA release from nanoparticles. These new developed zein-casein-lysine nanoparticles may be used for FA sustained delivery by the oral route., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Here we report the biological and molecular characterization of a virulent genotype VII Newcastle disease virus (NDV) circulating in Venezuela and the assessment of the vaccination efficacy under field conditions compared to controlled rearing conditions. Biological pathotyping showed a mean embryo dead time of 50 h and an intracerebral pathogenicity index of 1.86. Sequence-based phylogenetic analysis demonstrated that the virus belongs to genotype VII in class II (a genotype often found in Asia and Africa), representing the first report of the presence of this genotype in the continent of South America. A vaccine-challenge trial in commercial broilers reared in fields or in a experimental setting included dual (live/killed) priming of 1-day-old chicks plus two live NDV and infectious bursal disease virus (IBDV) field vaccinations at days 7 and 17, followed by a very stringent genotype VII NDV challenge at day 28. Serology for NDV and IBDV, bursal integrity, and protection against NDV lethal challenge were assessed. At 28 days, field vaccinates showed significantly lower NDV (1,356 versus 2,384) and higher IBD (7,295 versus 1,489) enzyme-linked immunosorbent assay (ELISA) antibody titers than the experimentally reared birds. A lower bursal size and bursa-body weight ratio (P < 0.05) and higher bursa lesion score were also detected in the field set. Only 57.1% of field vaccinates survived the lethal challenge, differing (P < 0.05) from 90.5% survival in the experimental farm. Overall, results confirmed the presence of the genotype VII viruses in South America and suggest that field-associated factors such as immunosuppression compromise the efficacy of the vaccination protocols implemented.

Asthma, chronic obstructive pulmonary disease (COPD) and acute lung injury/acute respiratory distress syndrome (ALI/ARDS) are characterized by neutrophilic inflammation and elevated levels of leukotriene B4 (LTB4). However, the exact role of LTB4 pathways in mediating pulmonary neutrophilia and the potential therapeutic application of LTB4 receptor antagonists in these diseases remains controversial. Here we show that a novel dual BLT1 and BLT2 receptor antagonist, RO5101576, potently inhibited LTB4-evoked calcium mobilization in HL-60 cells and chemotaxis of human neutrophils. RO5101576 significantly attenuated LTB4-evoked pulmonary eosinophilia in guinea pigs. In non-human primates, RO5101576 inhibited allergen and ozone-evoked pulmonary neutrophilia, with comparable efficacy to budesonide (allergic responses). RO5101576 had no effects on LPS-evoked neutrophilia in guinea pigs and cigarette smoke-evoked neutrophilia in mice and rats. In toxicology studies RO5101576 was well-tolerated. Theses studies show differential effects of LTB4 receptor antagonism on neutrophil responses in vivo and suggest RO5101576 may represent a potential new treatment for pulmonary neutrophilia in asthma., (Copyright 2010 Elsevier Inc. All rights reserved.)

The inhibition of LTB(4) binding to and activation of G-protein-coupled receptors BLT1 and BLT2 is the premise of a treatment for several inflammatory diseases. In a lead optimization effort starting with the leukotriene B(4) (LTB(4)) receptor antagonist (2), members of a series of 3,5-diarylphenyl ethers were found to be highly potent inhibitors of LTB(4) binding to BLT1 and BLT2 receptors, with varying levels of selectivity depending on the substitution. In addition, compounds 33 and 38 from this series have good in vitro ADME properties, good oral bioavailability, and efficacy after oral delivery in guinea pig LTB(4) and nonhuman primate allergen challenge models. Further profiling in a rat non-GLP toxicity experiment provided the rationale for differentiation and selection of one compound (33) for clinical development.

We reviewed our cases of gastric MALT-lymphomas over a 12-year period at a national oncological referral center, the Instituto Nacional de Cancerología in Mexico City, looking for morphological evidence of Helicobacter pylori infection near the primary neoplasia. H pylori as well as lymphoid follicles and chronic active gastritis were carefully searched for in the adjacent mucosa. There were 23 (85%) low-grade and four (15%) high-grade MALT-lymphomas. H pylori microorganisms were found adjacent to the neoplasia in 23 cases (85%; CI 95% = 72-99%) but the lymphoid follicles were seen in 15 of 23 (65%; CI = 56-74%). Chronic active gastritis was present in 25 cases (93%; Cl = 90-95%). There was a close association between H pylori and gastric MALT-lymphoma. Lymphoid follicles were a reliable indicator of infection and the claimed pathophysiological substrate for MALT-lymphoma. We conclude that patients in whom gastric lymphoid follicles are detected, must remain under clinical follow-up since H pylori is a plausible promoter of neoplastic transformation.