91 research outputs found

    Murine Typhus in Child, Yucatan, Mexico

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    A case of murine typhus in Yucatan was diagnosed in a child with nonspecific signs and symptoms. The finding of Rickettsia typhi increases the number of Rickettsia species identified in Yucatan and shows that studies are needed to determine the prevalence and incidence of rickettsioses in Mexico

    Direct evidence of Rickettsia typhi infection in Rhipicephalus sanguineus ticks and their canine hosts

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    Murine typhus is a rickettsiosis caused by Rickettsia typhi, whose transmission is carried out by rat fleas in urban settlements as classically known, but it also has been related to cat fleas in a sub-urban alternative cycle that has been suggested by recent reports. These studies remarks that in addition to rats, other animals like cats, opossums and dogs could be implied in the transmission of Rickettsia typhi as infected fleas obtained from serologically positive animals have been detected in samples from endemic areas. In Mexico, the higher number of murine typhus cases have been detected in the Yucatan peninsula, which includes a great southeastern region of Mexico that shows ecologic characteristics similar to the sub-urban alternative cycle recently described in Texas and California at the United States. To find out which are the particular ecologic characteristics of murine typhus transmission in this region, we analyzed blood and Rhipicephalus sanguineus ticks obtained from domestic dogs by molecular approaches, demonstrating that both samples were infected by Rickettsia typhi. Following this, we obtained isolates that were analyzed by genetic sequencing to corroborate this infection in 100% of the analyzed samples. This evidence suggests for the first time that ticks and dogs could be actively participating in the transmission of murine typhus, in a role that requires further studies for its precise description.Keywords: Dogs, Murine typhus, Rhipicephalus sanguineus, Rickettsia typhi, Vecto

    First histopathological study in kidneys of rodents naturally infected with Leptospira pathogenic species from Yucatan, Mexico

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    AbstractObjectiveTo report the renal histological lesions in synanthropic rodents, Mus musculus and Rattus rattus, naturally infected with Leptospira spp., captured in a rural community in Yucatan, Mexico.MethodsKidney samples of synanthropic rodents were collected from a rural community in Yucatan, Mexico. Polymerase chain reaction was used to detect Leptospira spp. infection. Tissue kidney was fixed in 10% buffered formalin, processed according to the usual techniques for paraffin inclusion, cut and stained with hematoxylin and eosin, and examined using a conventional electronic microscope.ResultsA total of 187 rodents were captured. Nine individuals (4.8%) were positive for Leptospira spp. in the molecular analysis. All renal lesions observed in the histopathological study had been reported previously for Leptospira spp. infection.ConclusionsThe histopathological lesions are present in the kidneys, plus the results of the polymerase chain reaction confirm that these rodents are true carriers of Leptospira spp

    Valorización de Cementos Pacasmayo S.A.A.

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    El presente trabajo de investigación tiene como objetivo hallar el valor fundamental de la empresa Cementos Pacasmayo S.A.A. al cierre del año 2020. Para ello se ha utilizado diferentes metodologías, principalmente el Flujo de Caja Descontado, y adicionalmente la valorización por múltiplos. La empresa se ubica como la segunda compañía cementera más importante del país y lidera el mercado cementero en la zona nororiental del país, con un 98% de participación. Cementos Pacasmayo cuenta actualmente con un modelo integrado de negocio que engloba desde la extracción de la materia prima, producción, venta y distribución de sus productos a cargo de sus empresas subsidiarias. La empresa cuenta con tres plantas de producción en el norte del Perú (Piura, Pacasmayo y Rioja) y tiene sede administrativa en Lima

    Latinamerican guidelines of RIICER for diagnosis of tick-borne rickettsioses

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    Las rickettsiosis transmitidas por garrapatas son afecciones de distribución mundial, que por diferentes motivos se pueden considerar emergentes y reemergentes. Hasta hace escasos años la única rickettsiosis transmitida por garrapatas en Latinoamérica era la infección por Rickettsia rickettsii, pero en la actualidad y fundamentalmente, gracias a la incorporación de nuevas herramientas para el diagnóstico microbiológico como la reacción en cadena de la polimerasa y secuenciación o el cultivo celular rápido en tubo cerrado, se han descrito e involucrado otras especies de Rickettsia en la producción de patología humana. En estas guías se detallan y describen las diferentes técnicas utilizadas para el diagnóstico microbiológico de las rickettsiosis. Además, se incluye una sección en la que se detallan las especies más importantes de garrapatas duras relacionadas con las rickettsiosis en Latinoamérica, con claves para su clasificación taxonómica.Tick-borne rickettsioses are worldwide infectious diseases that are considered emerging and re-emerging. Until recently the only tick-borne rickettsiosis present in Latin America was Rickettsia rickettsii infection, but to date, with the incorporation of new tools as PCR and sequencing and the quick cellular close tube cultures (Shell-vial), new species has been involved as human pathogens. In these guidelines, we offer an update of the microbiological assays for diagnosing rickettsioses. Besides we have included a section in which the most important hard ticks involved in human rickettsioses in Latinoamerica are detailed.Financiamiento: RIICER (Red Iberoamericana para la Investigación y Control de las Enfermedades Rickettsiales) del Programa Iberoamericano de Ciencia y Tecnología para el Desarrollo (CYTED)

    Učinak postupnog blanširanja u otopini kalcijeva klorida na teksturu i strukturu ukiseljenih „jalapeño” paprika

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    Jalapeño peppers incur texture changes during thermal processing due to loss of turgor pressure, tissue softening, and pectin solubility in the cell wall, which affects their quality and acceptability as a processed product among consumers. The objective of this work is to evaluate the effect of stepwise blanching with calcium chloride solution on firmness, calcium absorption and microstructural changes of jalapeño peppers. Batches of 1 kg of pepper halves were blanched at 65 °C for 4 min at different concentrations of CaCl2 (0, 0.075, 0.15 and 0.3 mol/L). After blanching, the peppers were removed, placed in plastic bags and submerged in a water bath at 65 °C for different holding times (0, 15, 30 and 45 min). Then the peppers were blanched again in an acidified solution at 96 °C for 3 min to remove enzymatic activity. Afterwards, peppers were packed in glass containers with brine at 95 °C and pasteurized at 85 °C for 10 min. The product was stored for 10 days at room temperature, then analyzed for texture, calcium absorption, pH, acidity, and microstructural changes. Results showed that CaCl2 concentration and blanching improved firmness with a maximum value of 3.68 N, a 4.3-fold increase over control. Calcium absorption increased with CaCl2 concentration reaching a maximum of 0.68 g of Ca2+ per kg of samples. Microscopy showed reduced cell wall damage in the samples that were blanched in 0.3 mol/L of CaCl2 at 45 min of holding time. The optimum processing conditions determined in thisstudy can be used for improving the firmness of peppers.Tijekom toplinske obrade mijenja se tekstura „jalapeño” paprika zbog gubitka turgora, mekšanja tkiva i topljivosti pektina u staničnim stijenkama, što utječe na njihovu kakvoću i prihvatljivost među potrošačima. Svrha je ovoga rada bila procijeniti učinak postupnog blanširanja u otopini kalcijeva klorida na čvrstoću tkiva, apsorpciju kalcija i mikrostrukturalne promjene „jalapeño” paprika. Šarže od 1 kg polovica paprika blanširane su 4 minute na 65 °C pri različitim koncentracijama CaCl2 (0; 0,075; 0,15 i 0,3 mol/L). Nakon blanširanja paprike su stavljene u plastične vrećice i potopljene u vodenu kupelj na 65 °C tijekom 0, 15, 30 i 45 min. Zatim su radi inaktivacije enzima 3 minute blanširane u zakiseljenoj otopini pri 96 °C, te pakirane u staklenke s rasolom (pri 95 °C) i pasterizirane na 85 °C tijekom 10 min. Naposljetku su 10 dana skladištene na sobnoj temperaturi, nakon čega je analizirana njihova tekstura, apsorpcija kalcija, pH, kiselost i mikrostrukturalne promjene. Rezultati pokazuju da CaCl2 i blanširanje poboljšavaju čvrstoću tkiva 4,3 puta (na maksimalnih 3,68 N), u usporedbi s kontrolnim uzorkom. Povećanjem koncentracije CaCl2 povećala se apsorpcija kalcija (maksimalno 0,68 g Ca2+/kg paprika). U uzorcima blanširanim 45 min u otopini CaCl2, koncentracije 0,3 mol/L, mikroskopski je utvrđeno manje oštećenje staničnih stijenki. Stoga je zaključeno da se čvrstoća paprika može poboljšati optimiranjem uvjeta prerade

    ‘Candidatus Rickettsia asemboensis’ and Wolbachia spp. in Ctenocephalides felis and Pulex irritans fleas removed from dogs in Ecuador

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    Abstract\ud \ud Background\ud Flea-borne infections are distributed worldwide. Up to date there are no reports about microorganisms associated to fleas in Ecuador.\ud \ud \ud Methods\ud Seventy-one Pulex irritans and 8 Ctenocephalides felis fleas were removed from dogs in two Ecuadorian areas (Pastaza and Chimborazo Provinces) in December 2012. DNA extracts were tested by polymerase chain reaction (PCR) assays targeting universal 16S rRNA, as well as screened for the presence of Rickettsia spp. (gltA, htrA, ompB, sca4 and ompA genes) and Bartonella spp. (rpoB, gltA and ITS genes).\ud \ud \ud Results\ud Our results showed the presence of ‘Candidatus Rickettsia asemboensis’ (highly similar to R. felis) in C. felis and Wolbachia spp. endosimbionts in P. irritans collected from animals in Ecuador. No fleas were found to be positive for any Bartonella species or Yersinia pestis.\ud \ud \ud Conclusions\ud Clinicians should be aware of the potential risk of this new Candidatus Rickettsia sp. and keep in mind other flea-borne infections since these flea species frequently bite humans

    Rickettsioses in Latin America, Caribbean, Spain and Portugal

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    Data on genus and infectious by Rickettsia were retrospectively compiled from the critical review literature regarding all countries in Latin America, Caribbean islands, Portugal and Spain. We considered all Rickettsia records reported for human and/or animal hosts, and/or invertebrate hosts considered being the vector. In a few cases, when no direct detection of a given Rickettsia group or species was available for a given country, the serologic method was considered. A total of 13 Rickettsia species have been recorded in Latin America and the Caribbean. The species with the largest number of country confirmed records were Rickettsia felis (9 countries), R. prowazekii (7 countries), R. typhi (6 countries), R. rickettsii (6 countries), R. amblyommii (5 countries), and R. parkeri (4 countries). The rickettsial records for the Caribbean islands (West Indies) were grouped in only one geographical area. Both R. bellii, R. akari, and Candidatus ‘R. andeane’ have been recorded in only 2 countries each, whereas R. massiliae, R. rhipicephali, R.monteiroi, and R. africae have each been recorded in a single country (in this case, R. africae has been recorded in nine Caribbean Islands). For El Salvador, Honduras, and Nicaragua, no specific Rickettsia has been reported so far, but there have been serological evidence of human or/and animal infection. The following countries remain without any rickettsial records: Belize, Venezuela, Guyana, Surinam, and Paraguay. In addition, except for a few islands, many Caribbean islands remain without records. A total of 12 Rickettsia species have been reported in Spain and Portugal: R. conorii, R. helvetica, R. monacensis, R. felis, R. slovaca, R. raoultii, R. sibirica, R. aeschlimannii, R. rioja, R. massiliae, R. typhi, and R. prowazekii. Amongst these Rickettsia species reported in Spain and Portugal, only R. prowazekii, R. typhi, R. felis, and R. massiliae have also been reported in Latin America. This study summarizes the current state of art on the rickettsial distribution in Latin America, Caribbean, Spain and Portugal. The data obtained allow a better understanding on rickettsial epidemiology and distribution of vector ecology.Reportes del genero Rickettsia y sus asociadas infecciones fueron compilados en una revisión crítica retrospectiva de la literatura científica de los países de Latinoamérica, el Caribe, Portugal y España. Se consideraron todos los reportes para huéspedes humanos y/o animales y también para huéspedes invertebrados los cuales fueron considerados como vectores asociados con Rickettsia. En algunos casos, cuando no existió detección directa a un determinado grupo de rickettsias o especies no disponible en un país, se tuvo en cuenta la detección indirecta por serología. Un total de 13 especies de Rickettsia han sido reportadas en Latinoamérica y el Caribe. Las especies más encontradas en los países fueron: Rickettsia felis (9 países), R. prowazekii (7 países), R. typhi (6 países), R. rickettsii (6 países), R. amblyommii (5 países) y R. parkeri (4 países). Los datos de las islas del Caribe (antillas menores o Indias occidentales), fueron agrupados en una sola área geográfica como un solo país. Ambas R. bellii, R. akari y Candidatus ‘R. andeane’ fueron reportadas en solo 2 países, mientras que R. massiliae, R. rhipicephali, R.monteiroi, y R. africae fueron informadas en un solo país. En este caso R. africae fue reportada en 9 islas de las Antillas menores. Para El Salvador, Honduras y Nicaragua, hasta ahora no se han reportado especies de Rickettsia, pero si evidencia serológica de infección humana y/o animal. Sin reportes de infección por Rickettsia permanecen: Belice, Venezuela, Guayana, Surinam y Paraguay. Además, a excepción de algunas islas del Caribe, muchas de ellas permanecen sin reportes. Un total de 12 especies de Rickettsia han sido documentadas en España y Portugal: R. conorii, R. helvetica, R. monacensis, R. felis, R. slovaca, R. raoultii, R. sibirica, R. aeschlimannii, R. rioja, R. massiliae, R. typhi y R. prowazekii. Entre estas, solamente R. prowazekii, R. typhi, R. felis y R. massiliae han sido documentados en Latinoamérica, España y Portugal. Los datos de este estudio permiten entender mejor la epidemiología de las rickettsias en Latinoamérica, Caribe, España y Portugal, y la distribución de los vectores

    Mecanismos de resistencia antifúngica de los azoles en Candida albicans. Una revisión

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    Candida albicans es una levadura comensal capaz de causar una infección oportunista en hospederos susceptibles denominada candidiasis. El tratamiento para combatir la candidiasis puede ser tópico o sistémico según el tipo de infección, los antifúngicos más utilizados son los derivados imidazólicos (fluconazol, itraconazol, ketoconazol, miconazol etc.), sin embargo en la actualidad se observa una disminución en la efectividad de estos medicamentos, es decir, un fenómeno de resistencia de parte del microorganismo a estos fármacos, esto debido principalmente, al surgimiento de levaduras resistentes, a la aparición de nuevas especies patógenas, a la prescripción irracional de antimicóticos como profilaxis y al aumento de las dosis terapéuticas. Existen dos mecanismos por los que Candida puede adquirir resistencia a un azol. El primero es por mutaciones moleculares de la enzima diana del antifúngico, como la alteración de las enzimas relacionadas en la síntesis del ergosterol y el segundo por la alteración en las bombas de expulsión: ATP-binding cassette (ABC) y facilitadores mayores (MF). En este trabajo se resumen los principales mecanismos de resistencia en Candida y la importancia de hacer pruebas de susceptibilidad con el fin de brindar un tratamiento adecuado para este tipo de infecciones oportunistas
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