A Pilot Study to Evaluate Genipin in Staphylococcus aureus and Pseudomonas aeruginosa Keratitis Models: Modulation of Pro-Inflammatory Cytokines and Matrix Metalloproteinases.

Infectious keratitis is a vision-threatening microbial infection. The increasing antimicrobial resistance and the fact that severe cases often evolve into corneal perforation necessitate the development of alternative therapeutics for effective medical management. Genipin, a natural crosslinker, was recently shown to exert antimicrobial effects in an ex vivo model of microbial keratitis, highlighting its potential to serve as a novel treatment for infectious keratitis. This study aimed to evaluate the antimicrobial and anti-inflammatory effects of genipin in an in vivo model of Staphylococcus aureus (S. aureus) and Pseudomonas aeruginosa (P. aeruginosa) keratitis. Clinical scores, confocal microscopy, plate count, and histology were carried out to evaluate the severity of keratitis. To assess the effect of genipin on inflammation, the gene expression of pro- and anti-inflammatory factors, including matrix metalloproteinases (MMPs), were evaluated. Genipin treatment alleviated the severity of bacterial keratitis by reducing bacterial load and repressing neutrophil infiltration. The expression of interleukin 1B (IL1B), interleukin 6 (IL6), interleukin 8 (IL8), interleukin 15 (IL15), tumor necrosis factor-α (TNF-α), and interferon γ (IFNγ), as well as MMP2 and MMP9, were significantly reduced in genipin-treated corneas. Genipin promoted corneal proteolysis and host resistance to S. aureus and P. aeruginosa infection by suppressing inflammatory cell infiltration, regulating inflammatory mediators, and downregulating the expression of MMP2 and MMP9.

Natural Plasmodium falciparum Infection Stimulates Human Antibodies to MSP1 Epitopes Identified in Mice Infection Models upon Non-Natural Modified Peptidomimetic Vaccination.

(1) Background: Malaria, a vector-borne infectious disease, is caused by parasites of the Plasmodium genus, responsible for increased extreme morbidity and mortality rates. Despite advances in approved vaccines, full protection has not yet been achieved upon vaccination, thus the development of more potent and safe immuno-stimulating agents for malaria prevention is a goal to be urgently accomplished. We have focused our research on a strategy to identify Plasmodium spp. epitopes by naturally acquired human antibodies and rodent malaria infection models immunized with site-directed non-natural antigens. (2) Methods: Some predictive algorithms and bioinformatics tools resembling different biological environments, such as phagosome-lysosome proteolytic degradation, affinity, and the high frequency of malaria-resistant and -sensitive HLA-II alleles were regarded for the proper selection of epitopes and potential testing. Each epitope's binding profile to both host cells and HLA-II molecules was considered for such initial screening. (3) Results: Once selected, we define each epitope-peptide to be synthesized in terms of size and hydrophobicity, and introduced peptide-bond surrogates and non-natural amino acids in a site-directed fashion, and then they were produced by solid-phase peptide synthesis. Molecules were then tested by their antigenic and immunogenic properties compared to human sera from Colombian malaria-endemic areas. The antigenicity and protective capacity of each epitope-peptide in a rodent infection model were examined. The ability of vaccinated mice after being challenged with P. berghei ANKA and P. yoelii 17XL to control malaria led to the determination of an immune stimulation involving Th1 and Th1/Th2 mechanisms. In silico molecular dynamics and modeling provided some interactions insights, leading to possible explanations for protection due to immunization. (4) Conclusions: We have found evidence for proposing MSP1-modified epitopes to be considered as neutralizing antibody stimulators that are useful as probes for the detection of Plasmodium parasites, as well as for sub-unit components of a site-directed designed malaria vaccine candidate.

Amblyomma nodosum Neumann, 1889 on collared anteaters (Tamandua tetradactyla) from the Andean region of Colombia / Amblyomma nodosum Neumann, 1889 em Tamanduá-mirim (Tamandua tetradactyla) da Região Andina Colombiana

Abstract Amblyomma nodosum is a Neotropical tick species distributed from Mexico to Argentina, with adult individuals infesting different mammal species, including anteaters (Pilosa: Myrmecophagidae). Few reports in Colombia have recorded this species in departments such as Meta, Tolima and Valle del Cauca. In this paper we describe this species using taxonomic, morphometric and molecular methods after collecting individuals parasitizing collared anteaters (Tamandua tetradactyla) in the departments of Cundinamarca and Tolima. Adult specimens were identified based on current taxonomic keys and different morphometric variables were documented in nonengorged individuals. Also, DNA was extracted for PCR amplification and sequencing of 16S rDNA, COI and ITS2 genes. Phylogenetic trees were built. One hundred and thirty-four adult ticks were collected and identified as Amblyomma nodosum, based on morphological, morphometric, molecular and phylogenetic analyses. This is the first study to report the presence of this tick species in the department of Cundinamarca, using multiple identification approaches, thus expanding its geographical records in Colombia.

Resumo Amblyomma nodosum é uma espécie de carrapato Neotropical distribuída do México à Argentina com indivíduos adultos, infestando diversas espécies de mamíferos, incluindo tamanduás (Pilosa: Myrmecophagidae). Na Colômbia, limitados relatos têm registrado essa espécie em alguns departamentos como Meta, Tolima e Valle del Cauca. Neste trabalho, espécimes foram identificados por meio de métodos taxonômicos, morfométricos e moleculares após serem coletados parasitando indivíduos de tamanduá-mirim (Tamandua tetradactyla) dos departamentos de Cundinamarca e Tolima. Espécimes adultos foram identificados por meio de chaves taxonômicas e diversas variáveis morfométricas foram ristradas em indivíduos não ingurgitados. Além disso, o DNA foi extraído para amplificação pela PCR e por sequenciamento dos genes 16S rDNA, COI e ITS2. Árvores filogenéticas foram construídas. No total, 134 carrapatos adultos foram coletados e identificados como Amblyomma nodosum por meio de análises morfológicas, morfométricas, moleculares e de filogenia. Este é o primeiro estudo que relata, por meio de múltiplas ferramentas de identificação, esta espécie no departamento de Cundinamarca ampliando assim seus registros geográficos na Colômbia.

A novel loop-mediated isothermal amplification-based test for detecting Neospora caninum DNA.

BACKGROUND: Neospora caninum is a cyst-forming, coccidian parasite which is known to cause neurological disorders in dogs and abortion and neonatal mortality in cows and other livestock. This study reports the development of a loop-mediated isothermal amplification (LAMP) assay based on the Neospora caninum Nc-5 gene and compares its efficacy for detecting DNA to that of a semi-nested PCR test. RESULTS: Six primers were designed based on the Nc-5 repeat region of N. caninum. Specific LAMP primers led to successful amplification of N. caninum DNA at 63 °C in 30 min. The LAMP assay was highly specific (i.e. it did not reveal cross-reactivity with other parasite species) and had a low N. caninum plasmid DNA limit of detection (1 fg), which is ten times higher than that for the semi-nested PCR. LAMP applicability was evaluated using a set of naturally-infected samples (59 from canine faeces and five from bovine abortions). Thirty-nine percent (25/64) of the naturally-infected samples were positive for N. caninum DNA by LAMP and 36% (23/64) by semi-nested PCR. However, the LAMP assay is much faster to perform than semi-nested PCR and provides results in 30 min. CONCLUSION: The optimized reaction conditions described in this study resulted in a sensitive, specific and rapid technique for detecting N. caninum DNA. Considering the advantages of LAMP for detecting N. caninum DNA, further assays aimed at testing its usefulness on a wider range of field samples are recommended.

Protecting capacity against malaria of chemically defined tetramer forms based on the Plasmodium falciparum apical sushi protein as potential vaccine components.

Developing novel generations of subunit-based antimalarial vaccines in the form of chemically-defined macromolecule systems for multiple antigen presentation represents a classical problem in the field of vaccine development. Many efforts involving synthesis strategies leading to macromolecule constructs have been based on dendrimer-like systems, the condensation of large building blocks and conventional asymmetric double dimer constructs, all based on lysine cores. This work describes novel symmetric double dimer and condensed linear constructs for presenting selected peptide multi-copies from the apical sushi protein expressed in Plasmodium falciparum. These molecules have been proved to be safe and innocuous, highly antigenic and have shown strong protective efficacy in rodents challenged with two Plasmodium species. Insights into systematic design, synthesis and characterisation have led to such novel antigen systems being used as potential platforms for developing new anti-malarial vaccine candidates.

Factores de riesgo asociados a la miiasis por cochliomyia hominivorax en fincas ganaderas de Puerto Boyacá (Colombia) / Associated risk factors to myiasis by cochliomyia hominivorax on cattle farms in Puerto Boyacá (Colombia)

Se realizó un estudio descriptivo-transversal en el municipio de Puerto Boyacá para identificar los factores de riesgo asociados a la miiasis por Cochliomyia hominivorax en bovinos. En 44 fincas ganaderas seleccionadas en un muestreo por conveniencia, se efectuó una entrevista personal a cada ganadero acerca del uso del suelo, sistema de producción ganadera y productos para el tratamiento de la miiasis traumática, entre el 6 y el 15 de febrero del 2007. El material suministrado para recolección de larvas fue recogido entre la última semana de abril y la primera semana de mayo del 2007. Análisis de frecuencias, medidas de asociación y pruebas no paramétricas fueron utilizados. Se detectaron 49 casos (0,4 por ciento) de miiasis por C. hominivorax en 12.325 bovinos registrados, en 18 (41 por ciento) de 44 fincas ganaderas. La causa de herida más frecuente fue abrasión por alambre de púas en 16 casos (32,7 por ciento). Los lugares de infestación más frecuente fueron el ombligo y el escroto con 9 casos (18,4 por ciento) cada uno. Se encontró asociación entre grupos etarios en bovinos y la presentación de casos por C. hominivorax (P=0,000; α=0,05). Se halló asociación entre el sistema de producción bovina y la presentación de casos por C. hominivorax (P=0,044; α=0,05). Se registró el uso de productos no adecuados en el tratamiento de la miiasis traumática como creolina (31 fincas), gasolina (4 fincas), aceite quemado (2 fincas), Baygon® (1 finca) y Vanodine® (1 finca). Se concluye que las fincas ganaderas seleccionadas compartieron factores de riesgo, según el sistema de producción ganadera. Se requiere intervención para evitar perjuicios en animales y consumidores por la utilización de productos no apropiados.

A Cross-sectional and descriptive study was carried out in countryside of Puerto Boyacá town for identification of Cochliomyia hominivorax myiasis risk factors on cattle. Fourty four cattle farms were selected with a not-random sampling. Personal interviews were carried out to livestock farmers. Land use, livestock production system, and products for treatment of screwworm myiasis were investigated on February 6-15 of 2007. Stuff and instructions were supplied for taking larvae from animal wounds afterwards register survey application. Those materials were collect since last week on April of 2007 until first week on May of 2007. Frequency analysis, cross-tabs measures and non parametric tests were used. 49 screwworm myiasis cases (0.4 percent) out of 12,325 registered cattle were found, in 18 (41 percent) out of 44 selected cattle farms. The main cause of wounds recorded was injury by barbed wire with 16 cases (32.7 percent). Body sites more frequently infested were navel and scrotum with 9 cases (18.4 percent) each one. Association between age group in cattle and screwworm myiasis cases was founded (P=0.000; α=0.05). Association between cattle production system and screwworm myiasis cases was founded (P=0.044; α=0.05). Usual handling of non appropriate products for screwworm myiasis treatment like “creolina” (31 farms), gasoline (4 farms), used motor lubricant oil (2 farms), Baygon® (1 farm) and Vanodine® (1 farm) was registered. It may be concluded that selected cattle farms shared risk factors, depending on cattle production system. It demands epidemiological intervention to avoid damages to animals and consumers for using of inappropriate products for treatment of traumatic myiasis.

Prevalencia de parásitos gastrointestinales zoonóticos (helmintos y protozoarios) en caninos del Centro de Zoonosis de Bogotá / Prevalence of zoonotic gastrointestinal parasites (helminths and protozoa) in canines at the Zoonosis Center of Bogota

El aumento del numero de mascotas, la falta de educación y el manejo un adecuado por parte de los propietarios, ha generado un incremento de poblaciones callejeras de caninos, que son una de las más importantes fuentes de contaminación de los ambientes urbanos, con huevos de helmintos y con quistes y ooquistes de protozoarios. El presente estudio determino la prevalencia de parásitos gastrointestinales en caninos recolectados por el Centro de Zoonosis de Bogotá a partir de 650 muestras fecales, distribuidas proporcionalmente por localidades. Mediante pruebas coprológicas se diagnosticó presencia de helmintos y protozoarios gastrointestinales, causantes de enfermedades zoonóticas en la población humana

The increase in the number of pets, the lack of education and inadequate management by pet owners has led to an increase in stray canine populations, which are one of the most important sources of contamination of urban environments with helminth eggs and with cysts and oocysts of protozoa. The present study determined the prevalence of gastrointestinal parasites in canines collected by the Zoonosis Center of Bogotá from 650 fecal samples, distributed proportionally by localities. The presence of gastrointestinal helminths and protozoa, which cause zoonotic diseases in the human population, was diagnosed by coprological tests: 156 samples (24%) showed no helminth or protozoan eggs or cysts, while positivity was observed in 494 (76%). The presence of Ancylostomidae eggs (Ancylostoma caninum, Uncinada stenocephala) was evidenced in 355 samples (71.9%), in 47 samples (9.5%) the presence of Toxocara canis eggs, in 9 (1.8%) the presence of Dipylidium caninum eggs, 8 samples (1.6%) Giardia spp. cysts and 6 samples (1.2%) Sarcocystis spp. oocysts. The high percentage of infected animals indicates that free canines are directly involved in the dissemination of helminths and protozoa relevant to public health in Bogota, such as Ancylostoma caninum, Toxocara canis, Dipylidium caninum, Giardia spp. and Sarcocystis spp. Although the parasitic problems generated by helminths are considered to have been overcome, this study reveals that their importance is maintained in free canine populations where there is no sanitary management, in addition to the fact that protozoa are important pathogens within emerging zoonotic diseases.