Synthesis, antileishmanial activity and QSAR studies of 2-chloro- N -arylacetamides

ABSTRACT We describe herein the synthesis and evaluation of the antileishmanial activity against promastigote forms of Leishmania amazonensis and cytotoxicity to murine macrophages of a series of 2-chloro-N-arylacetamide derivatives. All compounds were active, except one (compound 3). Compound 5 presented the most promising results, showing good antileishmanial activity (CI50=5.39±0.67 µM) and moderate selectivity (SI=6.36), indicating that further development of this class is worthwhile. Preliminary QSAR studies, although not predictive, furnished some insights on the importance of electronic character of aryl substituent to biological activity, as well as an indirect influence of hydrophobicity on activity.

Study of cutaneous leishmaniasis in the State of Campeche (Yucatan Peninsula), Mexico, over a period of two years / Estudio de la leishmaniasis cutánea en el estado de Campeche (Península de Yucatán), México, por un periodo de dos años

Objective. To study cutaneous leishmaniasis (CL), in the Calakmul municipality of the Campeche State, during two years. Materials and methods. Individuals with skin lesions were evaluated. Aspirates taken from the lesions were cultured, PCR was performed to diagnose the Leishmania species. Results. The culture detected 42% of the samples. PCR diagnosed CL in 76% of the samples; of those 38% were from children and 62% from adults. 89% of the patients were infected with L. mexicana; 14.4% with Mexican strains of L. mexicana; 7% with L. braziliensis; 3.6% with L. mexicana and L. braziliensis. The most affected villages with CL were Dos Lagunas Sur with 12.3%, La Mancolona with 6.5% and La Guadalupe with 2.2% of prevalence, respectively. After the treatment with Glucantime, 96% of the patients were healed. Conclusion. CL is an important public health concern in Calakmul, and the parasite causing it belongs to Leishmania mexicana and Leishmania braziliensis complexes.

Objetivo. Estudiar la leishmaniasis cutánea en Calakmul, Campeche, México, durante dos años. Material y métodos. Se estudiaron individuos con lesiones cutáneas, se tomaron aspirados y se inocularon medios de cultivo; se realizó la técnica de PCR para identificar la especie de Leishmania. Resultados. Los cultivos detectaron 42% de las muestras. Con la PCR se amplificaron 76% de las muestras, 38% fueron tomadas de niños y 62% de adultos. En 89% de las muestras positivas se identificó Leishmania mexicana, en 14.4% cepas mexicanas de L. mexicana, en 7% L. braziliensis y en 3.6% L. mexicana y L. braziliensis. En Dos Lagunas Sur se encontró una prevalencia de 12.3%, en La Mancolona 6.5% y en La Virgen 2.2%. Del total de los pacientes, 96% se curó con Glucantime. Conclusion. La leishmaniasis cutánea es un problema de salud pública en Calakmul y las especies causantes pertenecen a los complejos Leishmania mexicana y Leishmania braziliensis.

Sand fly captures with Disney traps in area of occurrence of Leishmania (Leishmania) amazonensis in the state of Mato Grosso do Sul, mid-western Brazil / Capturas de flebotomíneos com armadilhas de Disney em área de ocorrência de Leishmania (Leishmania) amazonensis no estado de Mato Grosso do Sul, região Centro-Oeste do Brasil

INTRODUCTION: The work was conducted to study phlebotomine fauna (Diptera: Psychodidae) and aspects of American cutaneous leishmaniasis transmission in a forested area where Leishmania (Leishmania) amazonensis occurs, situated in the municipality of Bela Vista, State of Mato Grosso do Sul, Brazil. METHODS: The captures were conducted with modified Disney traps, using hamster (Mesocricetus auratus) as bait, from May 2004 to January 2006. RESULTS: Ten species of phlebotomine sandflies were captured: Brumptomyia avellari, Brumptomyia brumpti, Bichromomyia flaviscutellata, Evandromyia bourrouli, Evandromyia lenti, Lutzomyia longipalpis, Psathyromyia campograndensis, Psathyromyia punctigeniculata, Psathyromyia shannoni and Sciopemyia sordellii. The two predominant species were Ev bourrouli (57.3 percent) and Bi flaviscutellata (41.4 percent), present at all sampling sites. Two of the 36 hamsters used as bait presented natural infection with Leishmania. The parasite was identified as Leishmania (Leishmania) amazonensis. CONCLUSIONS: Analysis of the results revealed the efficiency of Disney traps for capturing Bichromomyia flaviscutellata and the simultaneous presence of both vector and the Leishmania species transmitted by the same can be considered a predictive factor of the occurrence of leishmaniasis outbreaks for the human population that occupies the location.

INTRODUÇÃO: O estudo foi realizado com o objetivo de estudar a fauna de flebotomíneos (Diptera: Psychodidae) e aspectos ligados à transmissão da leishmaniose tegumentar americana em uma área florestal com ocorrência de Leishmania (Leishmania) amazonensis, situada no município de Bela Vista, Estado do Mato Grosso do Sul, Brasil. MÉTODOS: As capturas de flebotomíneos foram realizadas utilizando-se armadilhas tipo Disney modificadas, com isca roedor, Mesocricetus auratus, no período de maio de 2004 a janeiro de 2006. RESULTADOS: As coletas resultaram na identificação de 10 espécies de Phlebotominae: Brumptomyia avellari, Brumptomyia brumpti, Bichromomyia flaviscutellata, Evandromyia bourrouli, Evandromyia lenti, Lutzomyia longipalpis, Psathyromyia campograndensis, Psathyromyia punctigeniculata, Psathyromyia shannoni e Sciopemyia sordellii. As duas espécies predominantes foram Ev bourrouli, com 57,3 por cento dos espécimes coletados, e Bi. flaviscutellata, representada por 41,4 por cento e que esteve presente em todos os locais amostrados. Dois hamsters sentinelas adquiriram a infecção natural, sendo os isolados identificados como Leishmania amazonensis. CONCLUSÕES: Os resultados mostram a eficiência das armadilhas Disney para captura de Bichromomyia flaviscutellata, e a presença simultânea de ambos, o vetor e a espécie de Leishmania por ele transmitida pode ser considerada um fator preditor da ocorrência de leishmaniose para a população humana que permanecer nesse local.

Comparison of small mammal prevalence of Leishmania (Leishmania) mexicana in five foci of cutaneous leishmaniasis in the State of Campeche, Mexico / Comparación de las prevalencias de Leishmania (Leishmania) mexicana en mamíferos pequeños en cinco focos de leishmaniosis cutánea en el estado de Campeche, México

In the Yucatan Peninsula of Mexico, 95% of the human cases of Cutaneous Leishmaniasis are caused by Leishmania (Leishmania) mexicana with an incidence rate of 5.08 per 100,000 inhabitants. Transmission is limited to the winter months (November to March). One study on wild rodents has incriminated Ototylomys phyllotis and Peromyscus yucatanicus as primary reservoirs of L. (L.) mexicana in the focus of La Libertad, Campeche. In the present study, the prevalence of both infection and disease caused by L. (L.) mexicana in small terrestrial mammals were documented during five transmission seasons (1994-2004) in five foci of Leishmaniasis in the state of Campeche. Foci separated by only 100 km, with similar relative abundances of small mammals, were found to differ significantly in their prevalence of both symptoms and infection. Transmission rates and reservoir species seemed to change in space as well as in time which limited the implementation of effective control measures of the disease even in a small endemic area such as the south of the Yucatan Peninsula.

En la Península de Yucatán, México, la Leishmaniosis Cutánea es causada por Leishmania (L.) mexicana en 95% de los casos humanos, con una incidencia de 5.08% por cada 100,000 habitantes. El ciclo de transmisión se limita a la estación de invierno (noviembre- marzo). Un estudio de mamíferos silvestres incrimina a Ototylomys phyllotis y Peromyscus yucatanicus como reservorios primarios de L. (L.) mexicana en el foco de infección de La Libertad, Campeche. En el presente estudio, se documenta la prevalencia de infección/enfermedad causada por L. (L.) mexicana en pequeños mamíferos, durante cinco estaciones de transmisión (1994-2004) en cinco focos de CL del estado de Campeche. Los focos separados por solamente 100 km. de distancia, aún cuando tienen abundancias relativas de pequeños roedores similares, fueron significativamente diferentes en relación a la prevalencia de síntomas así como de infección. Las tasas de transmisión y las especies de reservorios parecen estar cambiando tanto en el tiempo como en el espacio, lo cual impide el establecimiento de adecuadas medidas de control de la enfermedad aún en un área endémica tan pequeña como lo es el sur de la Península de Yucatán.

Lesion aspirate culture for the diagnosis and isolation of Leishmania spp. from patients with cutaneous leishmaniasis

The detection of Leishmania spp. in skin lesion aspirates, using a puncture technique, was evaluated in 76 patients with cutaneous leishmaniasis (CL) who were referred to a Leishmaniasis Reference Centre in Brazil. CL was defined based on skin lesions suggestive of the disease and on a positive result of the Montenegro skin test or Giemsa-stained imprints of biopsy fragments. The aspirates were cultured using a vacuum tube device containing culture medium and evaluated for the presence of Leishmania spp. The biphasic medium culture was examined once a week for three weeks. Promastigotes were observed in 53/76 (69.7 percent) cultures. Stained smears from 60 of the 76 patients were evaluated using PCR-RFLP to detect the conserved minicircle region of Leishmania spp. and to classify the parasite. Of these patients, 45 (75 percent) showed positive results in aspirate culture and 15 presented negative results. The PCR was positive in 80 percent (53/60) samples. The PCR-RFLP profile was determined in 49 samples, of which 45 (92 percent) showed a pattern compatible with Leishmania (Viannia) braziliensis. The aspirate culture is a sensitive and feasible method for diagnosing CL and may be routinely adopted by health services for L. (V.) braziliensis isolation and identification.

Comparison of serological and parasitological methods for cutaneous leishmaniasis diagnosis in the state of Paraná, Brazil

We evaluated the effectiveness of serological and parasitological methods for cutaneous leishmaniasis (CL) diagnosis in patients from the central region of Paraná state, southern Brazil. Five groups were compared: clinical diagnosis, parasitological diagnosis, communicants, inhabitants of a non-endemic area and carriers of other etiologies. Two antigens were prepared from promastigotes of Leishmania (Viannia) braziliensis and Leishmania (Leishmania) amazonensis for indirect immunofluorescence assay, ELISA and immunoblotting. The parasitological approaches detected 79.3 percent of the patients with a clinical diagnosis; the parasites were identified by PCR as L. (V.) braziliensis. Serological methods showed 95 percent sensitivity for homologous antigens. Immunoblotting revealed specific proteins for diagnosis of CL and detected 96.6 percent of the patients when L. (V.) braziliensis was used as an antigen, and 83.3 percent with L. (L.) amazonensis. This study demonstrated the importance of differential diagnosis for leishmaniasis; the association of two or more indirect methods increased diagnosis sensitivity.

Leishmania mexicana infection of the eyelid in a traveler to Belize

A 50 year-old man, a United States resident, presented in Texas with a violaceous non-ulcerating lesion, involving the entire lower eyelid. The patient had traveled to a jungle area of Belize several hours drive from the capital city. Leishmania mexicana was isolated. The lesion only partially resolved after an initial course of sodium stibogluconate, requiring retreatment. At two years of follow-up, there was no relapse. The parasite isolated from the patient caused a progressive, non-ulcerating lesion in an experimental mouse footpad infection. This is an unusual case of cutaneous leishmaniasis in a traveler. Travelers must be educated about personal protective measures to prevent exotic infections acquired during travel.

Leishmania mexicana infection of the eyelid in a traveler to Belize

A 50 year-old man, a United States resident, presented in Texas with a violaceous non-ulcerating lesion, involving the entire lower eyelid. The patient had traveled to a jungle area of Belize several hours drive from the capital city. Leishmania mexicana was isolated. The lesion only partially resolved after an initial course of sodium stibogluconate, requiring retreatment. At two years of follow-up, there was no relapse. The parasite isolated from the patient caused a progressive, non-ulcerating lesion in an experimental mouse footpad infection. This is an unusual case of cutaneous leishmaniasis in a traveler. Travelers must be educated about personal protective measures to prevent exotic infections acquired during travel.

Clinical picture of cutaneous leishmaniases due to Leishmania (Leishmania) mexicana in the Yucatan peninsula, Mexico

Localized cutaneous leishmaniasis (LCL), known as "chiclero's ulcer" in southeast Mexico, was described by Seidelin in 1912. Since then, the sylvatic region of the Yucatan peninsula has been identified as an endemic focus of LCL. The purpose of the present work was to describe the clinical picture of LCL caused by Leishmania (Leishmania) mexicana in the Yucatan peninsula. A total of 136 cases of LCL, based on isolation and characterization of L. (L.) mexicana by isoenzymes and/or monoclonal antibodies, were selected. Some variability of clinical features regarding number, type, size, form, location and time of evolution of the lesions was observed. The most frequently observed presentation was a single, ulcerated, rounded small lesion, located on the ear, with an evolution time of less than three months, with neither cutaneous metastases nor lymphatic nor mucosal involvement. This picture corresponds to previous studies carried out in the same endemic area where an organism of the L. mexicana complex has been incriminated as a major aetiological agent of classical "chiclero's ulcer", confirming that in the Yucatan peninsula LCL due to L. (L.) mexicana when located on the pinna of the ear is a remarkable characteristic

Retention of Leishmania (Leishmania) mexicana in naturally infected rodents from the State of Campeche, Mexico

In the State of Campeche, Mexico, zoonotic cutaneous leishmaniasis is mainly due to Leishmania (L.) mexicana. The parasite population is maintained in a mammalian species, a reservoir in which the ideal course of infection should be long and relatively nonpathogenic. The objective of the present study was to document the retention of L. (L.) mexicana in 29 naturally infected rodents. These cricetids lived in captivity for up to two years and were tested monthly for the presence of the parasite, by cultures of needle aspirates from the base of the tail. Peromyscus yucatanicus and Ototylomys phyllotis were incriminated as the primary reservoir hosts. The finding that the multiplication of parasites in P. yucatanicus might be triggered by temperature, suggests that this animal would be a good choice for further research on L. (L.) mexicana.

Visceral leishmaniosis caused by Leishmania (L.) mexicana in a Mexican patient with human immunodeficiency virus infection

A 36 year old male was admitted in December 1997 to hospital with afternoon fever, malaise and hepatosplenomegaly. He also had a dry cough, dyspnoea and anaemia. Pneumonia caused by Pneumocystis carinii and human immunodeficiency virus (HIV) infection were documented. The HIV infection was confirmed in 1997 with 290,000 virus copies. The patient had been in the Mexican State of Chiapas which is known to be endemic for visceral leishmaniosis (VL) and localized cutaneous leishmaniosis (LCL). The visceral symptoms were diagnosed as VL and the causal agent was identified as Leishmania (L.) mexicana. Identification of Leishmania was carried out by the analysis of amplified DNA with specific primers belonging to the Leishmania subgenus and by dot blot positive hybridisation of these polymerase chain reaction derived products with kDNA from the L. (L.) mexicana MC strain used as probe. This is the first case in Mexico of VL caused by a species of Leishmania that typically produces a cutaneous disease form.

Use of monoclonal antibodies for the identification of Leishmania spp. isolated from humans and wild rodents in the State of Campeche, Mexico

The genus Leishmania includes 30 described species which infect a wide variety of mammalian hosts. The precise identification of leismanial parasites at the species level is very important in order to determine whether an organism, causing the disease in a given area, is of the same biotype as that found in suspected mammalian reservoir. the objectives of the present study were (1) to identify leismanial parasites isolated from humans and wild rodents from the State of Campeche, an endemic focus of localized cutaneous leishmaniasis (LCL) in southern Mexico, using an indirect immunofluorescent assay (IFA) with monoclonal antibodies (Mabs): and (2) to determine if the parasites of the two types of hosts wre of the same biotype. All the wild rodents (six Ototylomys phyllotis, eight Oryzomys melanotis, five Peromyscus yucatanicus and two Sigmodon hispidus) and 96 (por cento) (24/25) of the human isolates were identified as Leishmania (L.) mexicana confirming that this specific LCL focus is a wild zoonosis. The presence of one human isolate of L. (Viannia) braziliensis in the State of Campeche, conirmed the importance of an accurate taxonomic identification at species level.

Multiplicación in vitro de leishmania mexicana en macrófagos de hamsters y ratones infectados y no infectados / In vitro multiplication of leishmania mexicana in macrophages of infected and non infected hamsters and mice

Se evaluó la respuesta de macrófagos procedentes de la cavidad peritoneal de hamsters y ratones a la infección con promastigotos de Leishmania mexicana. También se determinó la curva proliferativa del parásito en cultivos de fagocitos que se obtuvieron en animales sin infección, infectados recientemente y con enfermedad. La multiplicación de Leishmania en los cultivos de animales sin infección previa fue bastante significativa, siendo más notable en macrófagos de los hamsters. En los macrófagos procedentes de animales infectados la proliferación del parásito fue prácticamente inhibida observándose además una mayor destrucción macrofágica

Presencia de nectomonadas metaciclicas de L. pifanoi en la hipofaringe de Lutzomyia youngi y la ingestion de azúcares / Metacyclical forms of L. pifanoi in the hypopharynx of Lutzomyia youngi and their sugar consuption

Se evidencia la presencia de promastigotos metacíclicos de Leishmania pifanoi en el conducto hipofaríngeo de Lutzomyia youngi infectados experimentalmente por ingurgitación sobre lesiones tarsales de hámsteres. La aparición de metacíclicos en la hipofaringe, cuya morfología se ilustra, ocurre entre los 5 y 9 días de desarrollo postprandial y es más frecuente en insectos alimentados com sacarose comercial no refinada. Se investiga el papel de derivados aminados de glucosa y galactosa y también de aminoácidos, en la promoción y migración de los metacíclicos

Estudio de casos de leishmaniasis en la provincia de Salta: evidencias de infeccion mixta por Trypanosoma cruzi y Leishmania spp / Study of cases of leishmaniasis in the Province of Salta: evidences of mixed infection with Trypanosoma cruzi and Leishmania spp

En numerosas regiones del Continente Americano y aun de Argentina existe superposición de áreas endémicas de dos importantes parasitoses como son la enfermedad de Chagas y la leishmaniasis. Los parásitos causantes de ambas pertenecen a la misma familia (Trypanosomatidae) por lo que el diagnóstico serológico diferencial con antígenos convencionales se ve dificultado por la existencia de fenómenos de reactividad cruzada. En este trabajo estudiamos pacientes provenientes de una zona endémica para ambas parasitosis (Tartagal-Orán, Salta) que consultaron por lesiones cutáneas o mucoctáneas compatibles con leishmaniasis. El estudio de los sueros, utilizando Ag complejos de Leishmania, mostró inusualmente altos porcentajes de positividad para pacientes leishmaniásicos. El análisis empleando pruebas convencionales frente a Ag heterólogos complejos de T. cruzi, reveló que la mayoría daban positivas estas reacciones. La utilización de 2 técnicas no convencionales para el diagnóstico de enfermedad de Chagas, permitó dividir los pacientes en 2 grupos: 1. Con evidencias de infección por T. cruzi: aquellos que dieron positivo en ELISA utilizando un Ag específico purificado con un Ac monoclonal (Ag163B6) o que presentaban un patrón de bandas característico de pacientes chagásicos por "immunoblotting" frente a epimastigotes; 2. Pacientes sin evidencias de infección por T. cruzi: aquellos negativos para ambas técnicas. Se pudo comprobar así que más del 50 por ciento de los leishmaniásicos presentaba fuertes evidencias de una infección concomitante con T. cruzi. Además, el alto grado de reactividad cruzada quedó de manifesto en el grupo de pacientes sin evidencia de infección por T. cruzi, ya que el 60 por ciento dio positivas al menos 2 reacciones convencionales considerándoselos por ende como chagásicos, pero dieron negativas ambas reacciones específicas. Estos resultados destacan la importancia de contar con Ag definidos y técnicas apropriadas para el diagnóstico serológico diferencial de estas parasitosis, lo cual cobra mayor importancia en las zonas donde ambas son endémicas.

Producción de anticuerpos monoclonales contra antígenos de Leishmania mexicana mexicana / Production of monoclonal antibodies against Leishmania mexicana mexicana antigens

En el presente trabajo se obtivieron tres AcMs: 1A6. 3H9 y 3F10. específicos contra la gp65 de la cepa de L.m.m/ (NR). Los tres AcMs fueron capaces de reconocer promastigotes de L.m.m. por inmunofluorecencia indirecta. En el análisis por inmunocitoquímica de biopsias con leishmania, fue posible observar amastigotes el los tejidos infectados

Comportamiento experimental del Sporothrix schenckii y la leishmania mexicana en el hamster / Experimental behavior of Sporothrix schenckii and leishmania mexicana in hamsters

La descripción macroscópica del proceso de patogénesis en hamsters inoculados subcutáneamente en nariz con Sporothrix schenckii ó Leishmania mexicana spp.proporcionó bases para diferenciar estos dos microorganismo en un modelo animal utilizado comunmente para estudiarlos. Observaciones secuenciales durante 150 días permitieran afirmar que en las infecciones causadas por estos patógenos se presentaron edema y eritema como signos primarios, seguidos de alopecia, necrosis y ulceración. La producción de pus fué una característica distintiva para el S. schenckii. Estos signos clínicos se observaron más temprano en la esporotricosis que en la infección por L.mexicana, mostrando diferencias estadísticas significantes en días promedio de aparición. El presente trabajo muestra que las lesiones produzidas tanto por el S.schenckii como la L. mexicana en este modelo experimental comparten signos clínicos, pero el tiempo de aparición de los mismo y su frecuencia relativa permiten diferenciarlas. Las condiciones de inoculación como: cepa de los microorganismos, dosis del inóculo, sitio y via de inoculación, deben tenerse presentes en la evaculación de su comportamiento experimental

Leishmaniasis cutánea causada por Leishmania mexicana amazonensis en Panamá / Cutaneous leishmaniasis caused by Leishmania mexicana amazonensis in Panama

Se presenta un caso humano de leishmaniasis cutánea causada por la Leishmania mexicana amazonensis en la República de Panamá. La cepa se identificó por medio de la electroforesis de isoenzimas de promastigotes. Su caracterización se basó en la movilidad de las enzimas G6PD, PGM, GPI, MPI, ME, 6PGD en acetato de celulosa. Se pudo observar que la cepa de L. m. amazonensis en estudio tuvo una migración electroforética completamente diferente a la cepa de la OMS, considerada como cepa de referencia para la L. m. mexicana, y a la cepa de referencia de L. m. aristedesi, que se mantiene en el Laboratorio Conmemorativo Gorgas. Sin embargo, fue indistinguible al de la cepa de OMS utilizada como referencia para L. m. amazonensis. Las observaciones realizadas en los animales inoculados con promastigotes de esta cepa, revelaron que su comportamiento era similar a cualquiera de los parásitos del complejo de la L. mexicana. Este es el primer caso informado en Centro América y Panamá

El agua de coco verde como base de un cultivo monofásico para Trypanosomatidae, parasítos del hombre en América / Fresh coconut water as monophasic cultive base from trypanosomatidae, parasite of men in America

El agua fresca de cocos verdes con 2% de hemolisado de sangre de conejo, con pH 6,2 ajustado con NaOH, preparada asépticamente, es un medio monofásico de cultivo eficiente para la diferenciación y mantenimiento prolongado de Trypanosomatidae, parásitos del hombre en América. El medio es útil tambien para el aislamiento de Phytomonas davidi

The susceptibility of wild caught sand flies to infection by a subspecies of Leishmania mexicana isolated from proechimys iheringi denigratus (Rodentia, echimyidae)

Várias espécies de flebotomíneos silvestres foram coletados no mesmo local onde o roedor Proechimys iheringi denigratus foi encontrado infectado com uma subespécie de Leishmania mexicana. A ausência de infecçäo natural desses flebotomíneos nos permitiu testar, com relativa segurança, a susceptibilidade de algumas dessas espécies à infecçäo por esse parasito. O sucesso obtido nas infecçöes experimentais sugere que uma ou mais das espécies de flebotomíneos encontradas em alta densidade nesse local podem ser um vetor, em potencial, dessa subespécie de L. mexicana