Antibiotic resistance of Salmonella strains from layer poultry farms in central Ecuador.

AIMS: This study evaluated the antimicrobial resistance of Salmonella enterica strains from layer poultry farms in central Ecuador isolated during 2017. This geographical area is responsible for around 60% of total domestic egg production, yet, as of 2019, no reports had been published on the phenotypic and genotypic antibiotic resistance patterns of Salmonella in the layer poultry farms of this area. METHODS AND RESULTS: Thirty-one isolates from layer poultry farms in central Ecuador obtained during 2017 were evaluated. The resistance profiles exhibited considerable differences in serovar and sample origin, grouping into nine clades by phenotype. S. Infantis strains were of the MDR phenotype in 94·4% of isolates. S. Typhimurium strains were of a reduced antimicrobial resistance phenotype and 50% showed resistance to one antimicrobial compound. One of the S. enterica nontyped strains had an MDR profile to 11 of the 20 antibiotics evaluated (eight groups). And the two remaining S. enterica nontyped strains showed resistance to two and three antibiotics respectively. The ESBL phenotype, which is resistant to clinically notable antibiotics such as ceftriaxone, ampicillin and cefepime, was observed only in S. Infantis (15/18). These strains harbour the emerging blaCTX-M-65 gene, and co-harbour tetA and sul1 resistance genes in four strains. Additional ß-lactamase genes, carbapenemase-producing genes (blaIMP, blaVIM , blaOXA48 , blaKPC , blaNDM ) and colistin-mobile resistance gene mcr-1 were not detected. CONCLUSIONS: The findings highlight the potential role of layer poultry farm environments in central Ecuador as reservoirs of MDR Salmonella strains. SIGNIFICANCE AND IMPACT OF THE STUDY: These results suggest the necessity of reinforcing biosecurity practices to reduce the probability of transmission of MDR Salmonella across the food chain.

Mechanisms of natural resistance of Balb/c mice to experimental liver amoebiasis.

Entamoeba histolytica is the parasite responsible for human amoebiasis. The analysis of the natural resistance mechanisms of some rodents to amoebic liver abscess (ALA) may reveal alternative pathogenicity mechanisms to those previously discovered in the experimental model of ALA in hamsters. In this work the natural resistance of BALB/c mice to ALA was explored by performing: (i) in vivo chemotaxis analysis with a specifically designed chamber; (ii) in vitro amoebic survival in fresh and decomplemented serum; (iii) histological temporal course analysis of ALA development in mice with different treatments (hypocomplementemic, hyperimmune and treated with iNOS and NADPH oxidase inhibitors) and (iv) mouse liver amoebic infection by both in situ implantation of ALA from hamsters and inoculation of parasites into the peritoneal cavity. The results show that E. histolytica clearance from the mouse liver is related to a low chemotactic activity of complement, which results in poor inflammatory response and parasite inability to cause tissue damage. Also, the absence of amoebic tropism for the mouse liver is correlated with resistance to experimental liver amoebiasis.

ß-Lactam Antibiotics Modify Root Architecture and Indole Glucosinolate Metabolism in Arabidopsis thaliana.

The presence of antibiotics in soils could be due to natural production by soil microorganisms or to the effect of anthropogenic activities. However, the impact of these compounds on plant physiology has not been thoroughly investigated. To evaluate the effect of ß-lactam antibiotics (carbenicillin and penicillin) on the growth and development of Arabidopsis thaliana roots, plants were grown in the presence of different amounts and we found a reduction in root size, an increase in the size of root hairs as well as an abnormal position closer to the tip of the roots. Those phenomena were dependent on the accumulation of both antibiotics inside root tissues and also correlated with a decrease in size of the root apical meristem not related to an alteration in cell division but to a decrease in cell expansion. Using an RNA sequencing analysis, we detected an increase in the expression of genes related to the response to oxidative stress, which would explain the increase in the levels of endogenous reactive oxygen species found in the presence of those antibiotics. Moreover, some auxin-responsive genes were misregulated, especially an induction of CYP79B3, possibly explaining the increase in auxin levels in the presence of carbenicillin and the decrease in the amount of indole glucosinolates, involved in the control of fungal infections. Accordingly, penicillin-treated plants were hypersensitive to the endophyte fungus Colletotrichum tofieldiae. These results underscore the risks for plant growth of ß-lactam antibiotics in agricultural soils, and suggest a possible function for these compounds as fungus-produced signaling molecules to modify plant behavior.

Entamoeba histolytica and Entamoeba dispar infection in Mexican school children: genotyping and phylogenetic relationship.

BACKGROUND: This study aimed to determine the frequency of Entamoeba histolytica and Entamoeba dispar infection in school children in the community of Tlaltizapan, in order to understand the dynamics of infection within the school and family spheres of this population. Amoebiasis is an unsolved public health problem and an endemic disease in Mexico. The incidence rate varies depending on the state; the most affected states show the highest numbers of new cases of amoebiasis per year. Previously, we reported the molecular frequency of infection with E. histolytica and/or E. dispar in other rural communities of the state of Morelos. METHODS: Children from 3 schools were studied to estimate the frequency of intestinal parasites through microscopic examination of fresh stool samples. The number of studied individuals were 309 school children. The molecular characterization of E. histolytica or E. dispar was carried out by Polymerase Chain Reaction (PCR) using species-specific primers to amplify short tandem repeats (STR) in non-coding sequences associated with the tRNA gene; the amplified fragments were sequenced and analyzed. RESULTS: Eight different genotypes were obtained from E. dispar isolates with the molecular marker NKD3-D5. None of the cases in which the species E. histolytica was detected developed symptoms attributable to an invasive process of disease. Moreover, the parasitized condition appeared to have no significant impact on the development or nutritional status of affected children. Genotype 1, which corresponds to the reference strain E. dispar SAW760, considered a non-pathogenic amoeba, was the most prevalent. CONCLUSIONS: The comparison of the genotypes of Entamoeba species did not show a correlation between children and their relatives. In this community, the species Entamoeba dispar genotype 1 was the most widespread. Based on the indicators of growth, development and nutrition status, the studied community seems to be reasonably adapted to constant exposure to intestinal parasites, since there were no evidences of a serious impact of the parasitized condition on the children's health.

The oxygen reduction pathway and heat shock stress response are both required for Entamoeba histolytica pathogenicity.

Several species belonging to the genus Entamoeba can colonize the mouth or the human gut; however, only Entamoeba histolytica is pathogenic to the host, causing the disease amoebiasis. This illness is responsible for one hundred thousand human deaths per year worldwide, affecting mainly underdeveloped countries. Throughout its entire life cycle and invasion of human tissues, the parasite is constantly subjected to stress conditions. Under in vitro culture, this microaerophilic parasite can tolerate up to 5 % oxygen concentrations; however, during tissue invasion the parasite has to cope with the higher oxygen content found in well-perfused tissues (4-14 %) and with reactive oxygen and nitrogen species derived from both host and parasite. In this work, the role of the amoebic oxygen reduction pathway (ORP) and heat shock response (HSP) are analyzed in relation to E. histolytica pathogenicity. The data suggest that in contrast with non-pathogenic E. dispar, the higher level of ORP and HSPs displayed by E. histolytica enables its survival in tissues by diminishing and detoxifying intracellular oxidants and repairing damaged proteins to allow metabolic fluxes, replication and immune evasion.

Efficacy and Safety of Rituximab in Biologic-Naive Patients with Rheumatoid Arthritis vs Anti-Tnf Therapy Failure.

OBJECTIVES: Our aim was to compare an AntiCD20 therapy (rituximab) for rheumatoid arthritis in two patient populations (Group 1), anti-TNFα naïve patients and inadequate responders to Anti-TNFα therapy (Group 2). METHODS: We analyzed the efficacy of the drug Rituximab (RTX) in RA patients who failed methotrexate (MTX) or had a relative or absolute contraindication to receive anti-TNFα therapy. RESULTS: 25 patients were identified according to the above criteria and followed up for a mean period of 6 months. Thirteen patients were biologic naïve and twelve patients had already failed anti-TNFα therapy. Group 1 used 2> DMARDs (32% vs 20%, p<0.005), group 2 had more years of disease progression (5±1.89 v s4.10±3.92, p<0.001). The remission as measured by the DAS28 reached faster in group 1 (1.25±0.12 vs 2.15±1.64, p<0,001). Severe infections especially by herpes viruses were more frequent in group 2. CONCLUSIONS: Comparing clinical improvement in both groups the decrease of acute phase reactants and the clinical remission measured by DAS28 was reached in both groups, however it was reached more belatedly in group 2 (at 6 months), this is due to the fact that they have more years of the disease evolution and a higher HAQ.

Case report: Cutaneous amebiasis: the importance of molecular diagnosis of an emerging parasitic disease.

Cutaneous amebiasis is the least common clinical form of human amebiasis in Mexico, sexual amebiasis was only occasionally observed before the late 1980s. However, in the last few decades, most of the documented cases of cutaneous amebiasis from around the world are sexually transmitted. We present two cases of sexually transmitted genital amebiasis. The molecular characterization of the Entamoeba species in the affected tissues underlines the importance of an etiological diagnosis using specific and sensitive techniques that avoid the rapid destruction of tissues and the irreversible sequelae to the anatomy and function of the affected organs. In addition, for those interested in the study of the human-amoebic disease relationship and its epidemiology, the detection of a new, mixed infection in an invasive case of amebiasis reveals new perspectives in the study of the extraordinarily complex host-parasite relationship in amebiasis.

Hurler's syndrome, West's syndrome, and vitamin D-dependent rickets.

Mucopolysaccharidosis I is a metabolic disease of autosomal recessive inheritance caused by deficient activity of alpha-L-iduronidase. The clinical phenotype presents a wide spectrum of signs in the first year of life. We report a child with clinical features and laboratory data consistent with mucopolysaccharidosis I who precociously developed hydrocephalus and flexion spasms with hypsarrythmia in the electroencephalographic registration characteristic of West's syndrome. His radiologic and biochemical data suggested vitamin D-dependent rickets. To our knowledge, this is the first report of a patient demonstrating an association among mucopolysaccharidosis 1, West's syndrome, and vitamin D-dependent rickets.

Manejo de celulitis con trimetoprín en el Hospital "Samuel Darío Maldonado" / Handling of cellulitis with trimertoprin in the Hospital \"Samuel Darío Maldonado\"

La celulitis es una infección de la piel, generalmente causada por el estreptococo o estafilococo, por lo que el tratamiento usado inicialmente es una penicilina o una cefalosporina, siendo la Oxacilina actualmente el antibiótico más usado en nuestro medio. Por lo que realizamos esta investigación prospectiva buscando otra alternativa para el manejo de las infecciones de la piel tipo celulitis. Se seleccionaron al azar 10 pacientes con edades comprendidas entre 1 y 55 años, sin enfermedad subyacente que presentaran signos de inflamación como: rubor, calor, edema, dolor y limitación funcional en algún sitio de la piel, así como síndrome de respuesta inflamatoria sistémica como T>38ºC, FC>90x'; FR>20x'. Se indicó como tratamiento trimetoprín sulfametoxazol (TMP/SMZ) a dosis 160/800 mg a adultos y 8 mg/Kg/día a niños calculado en base al trimetropín, usado por vía oral y como antiinflamatorio no esteroideo se usó ibuprofeno en todos los casos. Se evaluaron los pacientes dando un lapso de 36 a 48 horas para determinar mejoría o no. Se obtuvieron los siguientes resultados 9 de los 10 casos se resolvieron totalmente y en 1 paciente se presentó alergia al medicamento, con una estancia hospitalaria entre 4 y 8 días. Finalmente se puede concluir que la hipótesis planteada al inicio es aceptada, por lo que puede tenerse en cuenta al trimetoprín como una alternativa efectiva y económica en caso de una infección donde se sospeche la presencia del Estafilococo

Germenes más frecuentemente aislados en el Hospital Dr. Patrocinio Peñuela Ruiz: año 1997 conociendo al enemigo / Germs isolated frecuenting in the Dr. Patrocinio Peñuela Ruiz hospital: year 1997 to knwo inimical

Las enfermedades infecciosas han sido durante la historia de la medicina un problema de vital importancia. Los investigadores de países extranjeros han determinado los agentes causales y su frecuencia relacionado con cada patología datos por lo que se guía el médico a la hora de iniciar un tratamiento que en un comienzo será empírico. Sin embargo pensamos que la población de todos los países no es igual, así como su geografía, clima y condición económica lo que daría alguna diferencia al patrón que está escrito en los textos. Se realiza esta investigación con el objetivo de determinar los agentes más frecuentemente aislados en cada servicio por cada secreción. Se hizo de tipo retrospectivo durante 1 año revisando los reportes de cultivos realizados en el "Hospital Patrocinio Peñuela Ruiz" en el año 1997, obteniendo un total de 734 cultivos, siendo el germen aislado con mayor frecuencia la E.coli 114 casos, seguido por pseudomona aeruginosa 48 casos, estafilococo aureus con 37 casos. Los gérmenes gram negativos comandaron la frecuencia de gérmenes aislados en todas las secreciones excepto en las secreciones de abscesos