Prevalence of Trypanosoma cruzi and organ alterations in Virginia opossums (Didelphis virginiana) from western Mexico - short communication.

Small populations of Virginia opossum (Didelphis virginiana) in western Mexico are endangered by hunting and natural predators as well as by different kinds of diseases. After two serological analyses using Serodia® latex particle agglutination and indirect haemagglutination (IHA) tests, 35 (53.03%) of 66 collected opossums in two small towns in western Mexico were positive for the presence of Trypanosoma cruzi. Twenty-eight of the 35 seropositive opossums had pathological lesions: 11 had changes in only one organ, 13 in two organs, and four had pathological changes in three organs. Splenomegaly was the most common finding in the examined opossums, followed by hepatomegaly. These potentially fatal pathological changes could contribute to the scarcity of the opossum population, even leading to the extinction of this species in western Mexico.

Microscopic Observation Drug Susceptibility Assay for Rapid Diagnosis of Lymph Node Tuberculosis and Detection of Drug Resistance.

In this study, 132 patients with lymphadenopathy were investigated. Fifty-two (39.4%) were diagnosed with tuberculosis (TB). The microscopic observation drug susceptibility (MODS) assay provided rapid (13 days), accurate diagnosis (sensitivity, 65.4%) and reliable drug susceptibility testing (DST). Despite its lower sensitivity than that of other methods, its faster results and simultaneous DST are advantageous in resource-poor settings, supporting the incorporation of MODS into diagnostic algorithms for extrapulmonary TB.

Comparative bionomics of four populations of Meccus longipennis (Hemiptera: Reduviidae: Triatominae) under laboratory conditions.

The values of biological parameters related to the life cycles of four populations of Meccus longipennis (Reduviidae: Triatominae) were evaluated. Cohorts of each of the four studied populations from different geographical areas of Mexico were maintained under similar laboratory conditions and then compared. The population from El Saucito de Araujo was different from the other three studied populations, which could help explain the secondary importance of M. longipennis in the state of Chihuahua. This paper also supports the proposition that biological traits are important criteria for determining relationships between populations.

The biology of three Mexican-American species of Triatominae (Hemiptera: Reduviidae): Triatoma recurva, Triatoma protracta and Triatoma rubida.

The values of biological parameters related to hatching, lifespan, the number of blood meals between moults, mortality, time lapse before the beginning of feeding, feeding time and defecation delay for each instar of three Mexican-American species of Triatominae, Triatoma recurva, Triatoma protracta (former subspecies protracta) and Triatoma rubida (former subspecies uhleri), were evaluated and compared. No significant (p > 0.05) differences were recorded among the three species with respect to the average time required to hatch. This time was approximately 19 days. The average egg-to-adult development time was significantly (p < 0.05) shorter for T. rubida. The number of blood meals at each nymphal instar varied from one-five for each species. The mortality rates were higher for the first-instar nymphs of the three species studied. The mean time lapse before the beginning of feeding was between 0.3-3 min for most nymphs of all instars of each species studied. The mean feeding time was the longest for T. recurva, followed by T. protracta. The defecation delay was less than 10 min for T. recurva and T. rubida. Given these results, only T. rubida should be considered an important potential vector of Trypanosoma cruzi transmission to humans in areas of Mexico where these species exist, whereas T. recurva and T. protracta would be of secondary importance.

Microscopic observation drug susceptibility assay for tuberculosis screening before isoniazid preventive therapy in HIV-infected persons.

BACKGROUND: Active tuberculosis (TB) must be excluded before initiating isoniazid preventive therapy (IPT) in persons infected with human immunodeficiency virus (HIV), but currently used screening strategies have poor sensitivity and specificity and high patient attrition rates. Liquid TB culture is now recommended for the detection of Mycobacterium tuberculosis in individuals suspected of having TB. This study compared the efficacy, effectiveness, and speed of the microscopic observation drug susceptibility (MODS) assay with currently used strategies for TB screening before IPT in HIV-infected persons. METHODS: A total of 471 HIV-infected IPT candidates at 3 hospitals in Lima, Peru, were enrolled in a prospective comparison of TB screening strategies, including laboratory, clinical, and radiographic assessments. RESULTS: Of 435 patients who provided 2 sputum samples, M. tuberculosis was detected in 27 (6.2%) by MODS culture, 22 (5.1%) by Lowenstein-Jensen culture, and 7 (1.6%) by smear. Of patients with any positive microbiological test result, a MODS culture was positive in 96% by 14 days and 100% by 21 days. The MODS culture simultaneously detected multidrug-resistant TB in 2 patients. Screening strategies involving combinations of clinical assessment, chest radiograph, and sputum smear were less effective than 2 liquid TB cultures in accurately diagnosing and excluding TB (P<.01). Screening strategies that included nonculture tests had poor sensitivity and specificity. CONCLUSIONS: MODS culture identified and reliably excluded cases of pulmonary TB more accurately than other screening strategies, while providing results significantly faster than Lowenstein-Jensen culture. Streamlining of the ruling out of TB through the use of liquid culture-based strategies could help facilitate the massive up-scaling of IPT required to reduce HIV and TB morbidity and mortality.

Importance of Hybrids of Meccus phyllosomus mazzottii, and M. p. pallidipennis, and M. p. phyllosomus to the Transmission of Trypanosoma cruzi in Mexico.

The time interval before beginning feeding, feeding time, and defecation delay for 3 Triatominae subspecies, Meccus phyllosomus mazzottii (Ma), M. p. pallidipennis (Pa), and M. p. phyllosomus (Phy) and their laboratory hybrids were evaluated. The mean time interval for beginning feeding was between 0.1 and 10.1 min for all nymphal instars in each cohort, with significant (P < 0.05) differences among hybrids and parental cohorts. Four (both MaPa and MaPhy) hybrid cohorts had similar mean feeding times to that recorded for one of their parental subspecies, but shorter than the other, whereas the remaining hybrid cohorts (both PaPhy) had longer feeding times than did both of their parental subspecies. The specimens of MaPa defecated later than the respective instars on their parental subspecies, whereas most instars of the remaining 4 hybrid cohorts (MaPhy and PaPhy) defecated earlier than the respective instars of M. p. phyllosomus. Between 40% and 50% of the defecation events occurred when feeding in MaPhy and PaPhy hybrid cohorts. Given these results, the hybrid cohorts were more effective vectors of Trypanosoma cruzi than their parental subspecies, which could indicate a potentially higher risk of transmission of T. cruzi to reservoir hosts.

Crystal structures of N,N'-(m-tolyl)thiourea and N,N'-(p-tolyl)thiourea.

C15H16N2S is monoclinic [orthorhombic], P2(1)/c [Pbcn]. Unit-cell dimensions at 293 K are a = 9.506(1), b = 7.629(1), c = 20.077(1)A, beta = 99.93(1) degrees, V= 1434.2(2)A(3), D(x) = 1.187 g/cm3, and Z = 4 [a = 11.806(2), b = 13.954(2), c = 8.466(1)A, V = 1394.7(3)A(3), D(x) = 1.221 g/cm3, and Z = 8]. The R value is 0.049 [0.045] for 1620 [1229] observed reflections. The dihedral angle between the tolyl rings is 53.6(1) degrees [47.9(1)degrees]. The crystal structures are stabilized by N-H...S hydrogen bonds and van der Waals forces.

Etnobotánica de las flores de la pasión (Passiflora) en la provincia andina de Angaraes (Huancavelica, Perú) / Ethnobotany of passion flowers (Passiflora) in the Andean province of Angaraes (Huancavelica, Perú)

A study about the useful species of the genus Passiflora (Passifloraceae) found in a mountains province of Angaraes (Huancavelica, Perú) is presented. The methodology used was based on guided visits and semi-structured interviews to 50 informants who lived in the province of Angaraes. Seven species grouped in five categories of use were reported. Categories with a higher quantity of reported usage were food for humans (95 reports) and medicine (65 reports). The category with greater diversity of species was fodder (6 species). The part of the plant used most often was the fruit (80%). Two species were described as cultivated and five have been recorded as in wildlife state. The species with greater cultural importance were P. tripartita var. mollissima and P. pinnatistipula, since their fruits are much appreciated by the locals and commercialized in province fairs, demonstrating that the cultivation of these plant resources is the main livelihood in the region. Finally, a key is included in order to allow the identification of each of the species of Passiflora which inhabit in the study area.

Se presenta un estudio sobre las especies útiles del género Passiflora (Passifloraceae) de una provincia andina de Angaraes (Huancavelica, Perú). La metodología utilizada se basó en visitas guiadas y entrevistas semiestructuradas a 50 informantes de la provincia de Angaraes. Se reportaron siete especies agrupadas en cinco categorías de uso. Las categorías con mayores reportes de uso fueron alimento para humanos (95 reportes) y medicinal (65 reportes). La categoría con mayor riqueza de especies es alimento para animales (seis especies). La parte utilizada con mayor frecuencia es el fruto (80%). Dos especies fueron descritas como cultivadas y cinco han sido registradas en estado silvestre. Las especies con mayor importancia cultural fueron P. tripartita var. mollissima y P. pinnatistipula, siendo sus frutos muy apreciados y comercializados en las ferias de la provincia, lo cual demuestra que los pobladores dependen de sus recursos vegetales para su subsistencia. Finalmente, se incluye una clave que permite diferenciar las especies de Passiflora que habitan en la zona de estudio.

[Recurrent diarrhea due to Cystoisopora belli in HIV/AIDS patients receiving HAART]. / Diarrea recurrente por Cystoisopora belli en pacientes con infección por VIH con TARGA.

The Cystoisospora belli, before denominated as Isospora belli, is the etiologic agent of cystoisosoporiasis, an opportunistic infection affecting immunocompromised patients, characterized by chronic diarrhea and weight loss. The incidence of chronic diarrhea for this agent, in HIV patients, has decreased considerably. This thanks to the advent of highly active antiretroviral therapy (HAART), which has improved the patient's immune response and decrease viral load. We present six cases of cystoisosoporiasis recurrent and refractory to treatment in HIV patients, who was being treated with with trimethoprim / sulfamethoxazole (TMP / SMX) orally as a prophylaxis. Five of these patients passed away due to the infection, despite of the fact that they had a good response to HAART (adequate increase in CD4 and viral load undetectable) and they had been treated with second line drugs.

Combining two teaching techniques for young children on Aedes aegypti control: effects on entomological indices in western Mexico.

A study of the effect of educating four- to six-year-old children in mosquito control was recently conducted in a city in the state of Jalisco, western Mexico. Four neighborhood districts were selected. Children attending one kindergarten in each of two experimental districts were taught mosquito control with a video from the American Mosquito Control Association (AMCA), joined to the use of the AMCA Touch Table Technique. The entomological indices monitored in the study decreased significantly (P<0.05) in houses in the experimental districts, apparently because parents acted on the comments and suggestions of the children and eliminated or monitored containers used as oviposition sites by mosquitoes. Based on these results, combining both techniques for teaching children mosquito control is a potentially useful tool for control efforts in Mexico and other places in Latin America.

Otitis externa maligna con ectima gangrenoso en un paciente con infección por VIH / Malignant otitis externa with ecthyma gangrenosum in an hiv-positive patient

La otitis externa maligna es considerada una infección invasiva del conducto auditivo externo, infrecuente y sumamente agresiva, que llega, en ocasiones, a comprometer la base del cráneo. Se presenta habitualmente en inmunocomprometidos, incluidos aquellos con infección por VIH. El ectima gangrenoso es una infección cutánea localizada, inusual, causada, en la mayoría de los casos por Pseudomonas aeruginosa, con compromiso multisistémico y evolución tórpida. La asociación entre ambas entidades es aún más rara. A continuación, presentamos el caso de una mujer de 37 años, con el antecedente principal de infección por VIH desde hace 10 años, adherente al tratamiento antirretroviral y, a pesar de mantener una adecuada respuesta inmunológica y virológica, se presenta a la urgencia de nuestro hospital en shock séptico por otitis externa maligna, con ectima gangrenoso y posible síndrome hemofagocítico como complicación, aislándose Pseudomonas aeruginosa como agente causal.

Malignant otitis externa is an aggressive, infrequent and invasive infection of the external auditory canal. In some cases it leads to skull base compromise, particularly in immunocompromised individuals, including HIV-positive patients. Ecthyma gangrenosum is an unusual, localized cutaneous infection, caused mostly by Pseudomonas aeruginosa, with systemic compromise and a torpid evolution. An association between these 2 entities is even more rare. We present the case of a 37-year old woman with a history of 10 years’ HIV infection and good adherence to antiretroviral therapy. Although she had an adequate immunological and virological response, she presented at our emergency department in septic shock due to malignant otitis externa with ecthyma gangrenosum and possible haemophagocytic syndrome as a complication, with Pseudomonas aeruginosa determined to be the causative agent.

[Guillain Barré syndrome in association with Brucellosis]. / Síndrome de Guillain Barré asociado a Brucelosis.

We describe a case of a 47 years old male, with a history of 2 days of progressive, ascendant, symmetrical weakness in the lower extremities; a lumbar puncture was performed after the brain CT scan, as well as an electromyography, evidencing pure motor polyradiculopathy with axonal pattern, compatible with Guillain Barre syndrome. Afterwards, he received four plasmapheresis sessions, with clinical improvement from the second session. Due to his epidemiological background, Brucella set testing was done. Rose Bengal was positive, antibiotic treatment with rifampin and doxicicline was initiated, as well as rehabilitation. Three months later the patient recovered completely. The relevance of early treatment with plasmapheresis and the definition of the etiologic diagnosis determine that the prognosis of the Guillain Barre syndrome is favorable.

Diarrea recurrente por Cystoisopora belli en pacientes con infección por VIH con TARGA / Recurrent diarrhea due to Cystoisopora belli in HIV/AIDS patients receiving HAART

La Cystoisospora belli, antes denominada Isospora belli, es el agente etiológico de la cystoisosporiasis, una infección oportunista que afecta a pacientes inmunodeprimidos, caracterizada por diarrea crónica y pérdida ponderal. La incidencia de diarrea crónica por este agente, en pacientes infectados por el VIH, ha disminuido considerablemente. Ello gracias al advenimiento de la terapia antirretroviral de gran actividad (TARGA), con la que se ha logrado mejorar la respuesta inmunológica del paciente y disminuir su carga viral. Se presentan seis casos de cystoisosporiasis recurrente y refractaria en pacientes con infección por VIH, en quienes se diagnosticó cystoisosporiasis pese a que previamente se encontraban recibiendo profilaxis con trimetropin/sulfametoxazol (TMP/SMX). Cinco de ellos evolucionaron de manera tórpida y fallecieron, a pesar de una buena respuesta al TARGA (adecuado incremento de CD4 y disminución de la carga viral hasta rangos indetectables), y de tratamiento con TMP/SMX por vía oral y otros medicamentos de segunda línea.

The Cystoisospora belli, before denominated as Isospora belli, is the etiologic agent of cystoisosoporiasis, an opportunistic infection affecting immunocompromised patients, characterized by chronic diarrhea and weight loss. The incidence of chronic diarrhea for this agent, in HIV patients, has decreased considerably. This thanks to the advent of highly active antiretroviral therapy (HAART), which has improved the patient’s immune response and decrease viral load. We present six cases of cystoisosoporiasis recurrent and refractory to treatment in HIV patients, who was being treated with with trimethoprim / sulfamethoxazole (TMP / SMX) orally as a prophylaxis. Five of these patients passed away due to the infection, despite of the fact that they had a good response to HAART (adequate increase in CD4 and viral load undetectable) and they had been treated with second line drugs.

Treatment of Raynaud's phenomenon.

Raynaud's phenomenon is an episodic vasospasm of the peripheral arteries, causing pallor followed by cyanosis and redness with pain and sometimes paraesthesia, and, rarely, ulceration of the fingers and toes. Primary or idiopathic Raynaud's phenomenon (Raynaud's disease) occurs without an underlying disease. Secondary Raynaud's phenomenon (Raynaud's syndrome) occurs in association with an underlying disease. Initially conservative, non-pharmacologic approach is important for these patients, although pharmacologic therapy may ultimately be necessary. Advances in vascular physiology have showed the role of the endothelium as well as endothelium-independent mechanisms in the altered vasoregulation of Raynaud's phenomenon. This has opened promising therapeutic avenues, and it is likely that therapies targeted towards specific pathophysiologic steps become available in the near future.

Biological and genetic aspects of experimental hybrids from species of the Phyllosoma complex (Hemiptera: Reduviidae: Triatominae).

The present work is a thorough investigation of the degree of reproductive isolation between Meccus mazzottii and Meccus longipennis, Meccus picturatus, Meccus pallidipennis and Meccus bassolsae, as well as between M. longipennis and M. picturatus. We examined fertility and segregation of morphological characteristics in two generations of hybrids derived from crosses between these species. The percentage of pairs with (fertile) offspring was highest in the set of crosses between M. longipennis and M. picturatus, and lowest between M. mazzottii and M. picturatus. Most first-generation (F1) individuals from crosses involving M. mazzottii were morphologically similar to this species, while only F1 x F1 progeny of parental crosses between M. mazzottii and M. longipennis had offspring second generation that looked like M. mazzottii. The results indicate that different degrees of reproductive isolation apparently exist among the species of the Phyllosoma complex examined in this study. The biological evidence obtained in this study does not support the proposal that M. longipennis and M. picturatus are full species. It could indicate on the contrary, that both could be considered as subspecies of a single polytypic species. On the other hand, biological evidence supports the proposal that M. mazzottii is a full species.

Presencia de Meccus longipennis y Triatoma recurva en el estado de Durango, México / Presence of Meccus longipennis and Triatoma recurva in the state of Durango, Mexico

Se reporta por primera vez la recolecta de ejemplares de Meccus longipennis (Usinger) y de Triatoma recurva (Stål) en el estado de Durango. La búsqueda de triatominos se realizó durante 12 meses (septiembre 2010-agosto 2011) en cuatro comunidades de dos municipios (Pueblo Nuevo y Mezquital) del estado de Durango. Se recolectaron 71 ejemplares de M. longipennis y seis de T. recurva provenientes mayoritariamente del interior de las viviendas humanas (recámaras). La presencia de M. longipennis en el área abre la posibilidad de un riesgo potencial de transmisión de Trypanosoma cruzi Chagas a las poblaciones humanas del área estudiada.

The collection of Meccus longipennis (Usinger) and of Triatoma recurva (Stål) in the state of Durango is reported for the first time. Both species were collected during twelve months (from September 2010 to August 2011) in four localities of two municipalities (Pueblo Nuevo y Mezquital) in the state of Durango. Seventy one specimens of M. longipennis and six of T. recurva were collected mostly from indoors of human dwellings (bedrooms). Presence of M. longipennis means a potential risk of transmission of Trypanosoma cruzi Chagas to human populations in the study area.

The biology of three Mexican-American species of Triatominae (Hemiptera: Reduviidae): Triatoma recurva, Triatoma protracta and Triatoma rubida

The values of biological parameters related to hatching, lifespan, the number of blood meals between moults, mortality, time lapse before the beginning of feeding, feeding time and defecation delay for each instar of three Mexican-American species of Triatominae, Triatoma recurva, Triatoma protracta (former subspecies protracta) and Triatoma rubida (former subspecies uhleri), were evaluated and compared. No significant (p > 0.05) differences were recorded among the three species with respect to the average time required to hatch. This time was approximately 19 days. The average egg-to-adult development time was significantly (p < 0.05) shorter for T. rubida. The number of blood meals at each nymphal instar varied from one-five for each species. The mortality rates were higher for the first-instar nymphs of the three species studied. The mean time lapse before the beginning of feeding was between 0.3-3 min for most nymphs of all instars of each species studied. The mean feeding time was the longest for T. recurva, followed by T. protracta. The defecation delay was less than 10 min for T. recurva and T. rubida. Given these results, only T. rubida should be considered an important potential vector of Trypanosoma cruzi transmission to humans in areas of Mexico where these species exist, whereas T. recurva and T. protracta would be of secondary importance.

Síndrome de Guillain Barré asociado a Brucelosis / Guillain Barré Syndrome in association with Brucellosis

Se describe el caso de un varón de 47 años, con tiempo de enfermedad de dos días, caracterizado por pérdida de fuerza progresiva, simétrica y ascendente de miembros inferiores, se realizó punción lumbar luego de la tomografía cerebral y electromiografía lo cual evidenció polirradiculopatía motora pura con patrón axonal, compatible con el síndrome de Guillain Barré. Posteriormente, recibió cuatro sesiones de plasmaféresis, con mejoría clínica significativa desde la segunda sesión. Debido al antecedente epidemiológico se solicitó set para Brucellas, con rosa de Bengala positivo, se inició tratamiento antibiótico con rifampicina y doxiciclina, además de rehabilitación. Tres meses después el paciente mejoró completamente. La importancia del tratamiento temprano con plasmaféresis y determinar su diagnóstico etiológico hacen que el pronóstico del síndrome de Guillain Barré sea favorable.

We describe a case of a 47 years old male, with a history of 2 days of progressive, ascendant, symmetrical weakness in the lower extremities; a lumbar puncture was performed after the brain CT scan, as well as an electromyography, evidencing pure motor polyradiculopathy with axonal pattern, compatible with Guillain Barre syndrome. Afterwards, he received four plasmapheresis sessions, with clinical improvement from the second session. Due to his epidemiological background, Brucella set testing was done. Rose Bengal was positive, antibiotic treatment with rifampin and doxicicline was initiated, as well as rehabilitation. Three months later the patient recovered completely. The relevance of early treatment with plasmapheresis and the definition of the etiologic diagnosis determine that the prognosis of the Guillain Barre syndrome is favorable.

Biological and genetic aspects of experimental hybrids from species of the Phyllosoma complex (Hemiptera: Reduviidae: Triatominae)

The present work is a thorough investigation of the degree of reproductive isolation between Meccus mazzottii and Meccus longipennis, Meccus picturatus, Meccus pallidipennis and Meccus bassolsae, as well as between M. longipennis and M. picturatus. We examined fertility and segregation of morphological characteristics in two generations of hybrids derived from crosses between these species. The percentage of pairs with (fertile) offspring was highest in the set of crosses between M. longipennis and M. picturatus, and lowest between M. mazzottii and M. picturatus. Most first-generation (F1) individuals from crosses involving M. mazzottii were morphologically similar to this species, while only F1 x F1 progeny of parental crosses between M. mazzottii and M. longipennis had offspring second generation that looked like M. mazzottii. The results indicate that different degrees of reproductive isolation apparently exist among the species of the Phyllosoma complex examined in this study. The biological evidence obtained in this study does not support the proposal that M. longipennis and M. picturatus are full species. It could indicate on the contrary, that both could be considered as subspecies of a single polytypic species. On the other hand, biological evidence supports the proposal that M. mazzottii is a full species.