Prevalence and intensity of a Rickettsiales-like organism in cultured pleasure oyster, Crassostrea corteziensis, from Nayarit, Mexico.

Fastidious endosymbiotic Rickettsiales-like organisms (RLOs) have been observed in the digestive diverticula of the cultured pleasure oyster (Crassostrea corteziensis) from Nayarit, Mexico since 2007. In a few mollusk species, these bacteria have been associated with mortality events and production losses. The type of relationship between the RLOs and the pleasure oyster is largely unknown and further investigations are needed to determine if these bacteria warrant management concern in C. corteziensis. In this study, the morphological characteristics of the RLOs were studied by histology and SEM, and the taxonomic affiliations of the bacteria were evaluated by 16S rRNA amplicon sequencing. In addition, the prevalence and intensity of the RLOs was recorded from 2007 to 2017 by histology. The RLOs were observed inside circular basophilic cytoplasmic membrane bound vacuoles (MBVs) that had an average length and width of 15.70 ± 15.24 µm and 15.42 ± 14.95 µm respectively. Apart from cellular hypertrophy, no tissue alterations were observed in the areas adjacent to the RLOs. Individual bacteria within the MBVs were coccoid in shape with an average length of 0.65 ± 0.12 µm and an average width of 0.38 ± 0.09 µm. The bacterial microbiota of a selected number of samples (one sample without RLOs and two samples with RLOs) showed the presence of intracellular parasite OTUs corresponding to the families Rickettsiaceae and Anaplasmataceae, suggesting that the RLOs from the pleasure oyster is associated with the order Rickettsiales. A mean prevalence of 5 % was observed throughout the study period and the majority of the organisms (89 %) presented low intensity of Grade 1 (30-61 RLOs) of the MBVs. A higher prevalence of the RLOs was observed during warmer months. The lack of tissue alterations, the low prevalence and the low intensity of the MBVs suggest that the RLOs from C. corteziensis is a commensal endosymbiont that presents little risk for oyster production in Nayarit, México. However, regular monitoring is needed to detect if any variation in this relationship occurs, mainly in a scenario where extreme environmental fluctuations may occur.

[Recommendations for a multisectorial national policy to promote breastfeeding in Mexico: position of the National Academy of Medicine]. / Recomendaciones para una política nacional de promoción de la lactancia materna en México: postura de la Academia Nacional de Medicina.

Evidence strongly supports that to improve breastfeeding practices it is needed to strengthen actions of promotion, protection and support. To achieve this goal, it is necessary to establish a multisectoral national policy that includes elements such as design, implementation, monitoring and evaluation of programs and policies, funding research, advocacy to develop political willingness, and the promotion of breastfeeding from the national to municipal level, all coordinated by a central level. It is until now that Mexico has initiated a reform process to the establish a National Strategy for Breastfeeding Action. This strategy, is the result not only of the consistent scientific evidence on clear and strong benefits of breastfeeding on population health and the development of human capital, but also for the alarming data of deterioration of breastfeeding practices in the country. The comprehensive implementation of the National Strategy for Breastfeeding Action that includes the establishment of a national committee, intra- and inter-sectoral coordination of actions, setting clear goals and monitoring the International Code of Marketing of Breast-Milk Substitutes, is the awaiting responsibility of the public health agenda of the country.

Recomendaciones para una política nacional de promoción de la lactancia materna en México: postura de la Academia Nacional de Medicina / Recommendations for a multisectorial national policy to promote breastfeeding in Mexico: position of the National Academy of Medicine

Resumen: Para mejorar las prácticas de lactancia materna es necesario fortalecer acciones de promoción, protección y apoyo, y establecer una política nacional multisectorial que incluya elementos indispensables de diseño, implementación, monitoreo y evaluación de programas y políticas públicas, financiamiento para acciones e investigación, desarrollo de abogacía y voluntad política, y promoción de la lactancia materna, todo coordinado por un nivel central. Recientemente, México ha iniciado un proceso de reformas conducentes a la conformación de una Estrategia Nacional de Lactancia Materna (ENLM). Esta estrategia es el resultado de la disponibilidad de evidencia científica sobre los beneficios de la lactancia materna en la salud de la población y el desarrollo de capital humano así como de los datos alarmantes de su deterioro. La implementación integral de una ENLM que incluya el establecimiento de un Comité Nacional Operativo, coordinación intra e intersectorial de acciones, establecimiento de metas claras, monitoreo y penalización de las violaciones al Código Internacional de Comercialización de Sucedáneos de la Leche Materna, y financiamiento de estas acciones es la gran responsabilidad pendiente de la agenda de salud pública del país.

Abstract: Evidence strongly supports that to improve breastfeeding practices it is needed to strengthen actions of promotion, protection and support. To achieve this goal, it is necessary to establish a multisectoral national policy that includes elements such as design, implementation, monitoring and evaluation of programs and policies, funding research, advocacy to develop political willingness, and the promotion of breastfeeding from the national to municipal level, all coordinated by a central level. It is until now that Mexico has initiated a reform process to the establish a National Strategy for Breastfeeding Action. This strategy, is the result not only of the consistent scientific evidence on clear and strong benefits of breastfeeding on population health and the development of human capital, but also for the alarming data of deterioration of breastfeeding practices in the country. The comprehensive implementation of the National Strategy for Breastfeeding Action that includes the establishment of a national committee, intra- and inter-sectoral coordination of actions, setting clear goals and monitoring the International Code of Marketing of Breast-Milk Substitutes, is the awaiting responsibility of the public health agenda of the country.

[The role of health care providers in the late diagnosis of pulmonary tuberculosis among adults in Medellín, Colombia]. / Papel del personal de salud en el diagnóstico tardío de la tuberculosis pulmonar en adultos de Medellín, Colombia.

OBJECTIVE: To describe the role of health care providers in the delayed diagnosis of pulmonary tuberculosis (PTB) among the adult population in a city in Colombia. METHODS: A case study of PTB diagnosis among adults in the city of Medellín, Colombia, in 2007. Quantitative and qualitative data were collected through in-depth interviews with 19 patients (11 with early diagnosis and 8 with late diagnosis), from medical records, and by a survey of PTB-related knowledge and practices among 89 doctors and nurses at health care clinics. A research workshop was held with patients to share the results and validate new categories. RESULTS: A lack of PTB knowledge and patient stereotyping were found to lead to misinterpretation of symptoms and the use of symptomatic treatments. The lack of knowledge regarding risk factors and clinical protocols made diagnosis difficult when the patient did not match the stereotype or presented with a more well-known illness. Misinformation on PTB transmission and inappropriate measures led to discriminatory practices and social isolation and only reinforced stereotypes and stigma, which in turn discouraged the quest for medical attention. CONCLUSIONS: Health care providers played a large part in the late diagnosis of PTB in the adults studied. Beliefs regarding social stigma and a lack of knowledge about the disease-shared by providers and patients-contributed to stereotyping of the illness and the disease-carrier, and limited the probability of an early diagnosis of PTB.

Papel del personal de salud en el diagnóstico tardío de la tuberculosis pulmonar en adultos de Medellín, Colombia / The role of health care providers in the late diagnosis of pulmonary tuberculosis among adults in Medellín, Colombia

Objetivo: Describir el papel que desempeña el personal de salud (PS) en el retraso del diagnóstico de la tuberculosis pulmonar (TBP) en la población adulta de una ciudad colombiana. Métodos: Estudio de caso sobre el diagnóstico de la TBP en adultos de la ciudad de Medellín, Colombia, en 2007. Se recogieron datos cuantitativos y cualitativos mediante entrevistas en profundidad a 19 pacientes (11 con diagnóstico oportuno y 8 con diagnóstico tardío), la revisión de sus historias clínicas y encuestas sobre los conocimientos y las prácticas relacionadas con la TBP a 89 médicos y enfermeros de 12 instituciones prestadoras de servicios de salud. Se realizó un taller investigativo con los pacientes a fin de socializar los resultados y validar las categorías emergentes. Resultados: Se observó un escaso conocimiento sobre la TBP y una imagen estereotipada de los pacientes que llevan a malinterpretar los síntomas y emplear tratamientos sintomáticos. Los insuficientes conocimientos del PS sobre los factores de riesgo y el cuadro clínico dificultaron el diagnóstico cuando el paciente no reflejaba el estereotipo o presentaba una enfermedad ya conocida. La desinformación sobre la transmisión de la TBP y la prescripción incorrecta de medidas de aislamiento propiciaron prácticas discriminatorias y aislamiento social y reforzaron los estereotipos y la estigmatización, lo que también limitó la búsqueda de ayuda médica. Conclusiones: El PS desempeñó un papel fundamental en el diagnóstico tardío de la TBP en los adultos estudiados. Las creencias asociadas con el estigma social y el insuficiente conocimiento sobre la enfermedad -compartidos por el PS y los pacientes- contribuyen a la construcción social del estereotipo de la enfermedad y el enfermo y reducen las posibilidades de llegar a un diagnóstico oportuno de la TBP.

Objective: To describe the role of health care providers in the delayed diagnosis of pulmonary tuberculosis (PTB) among the adult population in a city in Colombia. Methods: A case study of PTB diagnosis among adults in the city of Medellín, Colombia, in 2007. Quantitative and qualitative data were collected through in-depth interviews with 19 patients (11 with early diagnosis and 8 with late diagnosis), from medical records, and by a survey of PTB-related knowledge and practices among 89 doctors and nurses at health care clinics. A research workshop was held with patients to share the results and validate new categories. Results: A lack of PTB knowledge and patient stereotyping were found to lead to misinterpretation of symptoms and the use of symptomatic treatments. The lack of knowledge regarding risk factors and clinical protocols made diagnosis difficult when the patient did not match the stereotype or presented with a more well-known illness. Misinformation on PTB transmission and inappropriate measures led to discriminatory practices and social isolation and only reinforced stereotypes and stigma, which in turn discouraged the quest for medical attention. Conclusions: Health care providers played a large part in the late diagnosis of PTB in the adults studied. Beliefs regarding social stigma and a lack of knowledge about the disease-shared by providers and patients-contributed to stereotyping of the illness and the disease-carrier, and limited the probability of an early diagnosis of PTB.

IFNgamma response to Mycobacterium tuberculosis, risk of infection and disease in household contacts of tuberculosis patients in Colombia.

OBJECTIVES: Household contacts (HHCs) of pulmonary tuberculosis patients are at high risk of Mycobacterium tuberculosis infection and early disease development. Identification of individuals at risk of tuberculosis disease is a desirable goal for tuberculosis control. Interferon-gamma release assays (IGRAs) using specific M. tuberculosis antigens provide an alternative to tuberculin skin testing (TST) for infection detection. Additionally, the levels of IFNgamma produced in response to these antigens may have prognostic value. We estimated the prevalence of M. tuberculosis infection by IGRA and TST in HHCs and their source population (SP), and assessed whether IFNgamma levels in HHCs correlate with tuberculosis development. METHODS: A cohort of 2060 HHCs was followed for 2-3 years after exposure to a tuberculosis case. Besides TST, IFNgamma responses to mycobacterial antigens: CFP, CFP-10, HspX and Ag85A were assessed in 7-days whole blood cultures and compared to 766 individuals from the SP in Medellín, Colombia. Isoniazid prophylaxis was not offered to child contacts because Colombian tuberculosis regulations consider it only in children under 5 years, TST positive without BCG vaccination. RESULTS: Using TST 65.9% of HHCs and 42.7% subjects from the SP were positive (OR 2.60, p<0.0001). IFNgamma response to CFP-10, a biomarker of M. tuberculosis infection, tested positive in 66.3% HHCs and 24.3% from the SP (OR = 6.07, p<0.0001). Tuberculosis incidence rate was 7.0/1000 person years. Children <5 years accounted for 21.6% of incident cases. No significant difference was found between positive and negative IFNgamma responders to CFP-10 (HR 1.82 95% CI 0.79-4.20 p = 0.16). However, a significant trend for tuberculosis development amongst high HHC IFNgamma producers was observed (trend Log rank p = 0.007). DISCUSSION: CFP-10-induced IFNgamma production is useful to establish tuberculosis infection prevalence amongst HHC and identify those at highest risk of disease. The high tuberculosis incidence amongst children supports administration of chemoprophylaxis to child contacts regardless of BCG vaccination.

Expresión de las moléculas de adhesión en la anemia drepanocítica / Expression of adhesion molecules in cases of drepanocytemia

En enfermos con anemia drepanocítica (AD) en estado basal y con crisis vasooclusivas dolorosas (CVOD), se estudió la expresión, en células mononucleares (CMN) y neutrófilos, de las moléculas de adhesión LFA-1, VLA-4, L-selectina e ICAM-1; en sangre periférica (SP), las moléculas VCAM-1 y CD34 y en fracciones de hematíes con diferente densidad, las moléculas VLA-4 y Lutheran, con anticuerpos monoclonales específicos mediante inmunofluorescencia indirecta por citometría de flujo. En ambos grupos de enfermos se observó una disminución significativa en la expresión en las CMN de las moléculas LFA-1 y VLA-4, y de LFA-1 en los neutrófilos de los pacientes en estado basal; disminución de la expresión de la molécula L-selectina en CMN y neutrófilos de pacientes en estado basal. El aumento de las moléculas ICAM-1 (CD54), CD34 y VCAM-1(CD106) en las CMN y sangre periférica de pacientes basales, demuestra la presencia de un estado de activación leucocitario y endotelial permanente determinado por la continua inflamación subclínica. El incremento significativo de ICAM-1 en neutrófilos y CD34 y VCAM-1 en sangre periférica en ambos grupos de pacientes, con mayor aumento de VCAM-1 en los pacientes en crisis, refleja la activación de monocitos, linfocitos, neutrófilos y de células endoteliales durante las CVOD, y la liberación de estas últimas a la periferia. Se observó una mayor expresión de las moléculas LFA-1, L-selectina e ICAM-1 en los neutrófilos de los enfermos con CVOD e incremento significativo de la molécula CD18 en CMN de los pacientes con CVOD, que puede explicarse por la activación de los monocitos en el fenómeno vasooclusivo.

In patients with drepanocytemia (DP) in basal state and with crises of painful vaso-occlusive (PVOC) authors studied the expression in mononuclear cells (MNC) and neutrophils, of LFA-1, VLA-4, L-selectine and ICAM-1; in peripheral blood (PB), VCAM-1 and CD34 molecules, and in red blood cells with different density, VLA-4 and Lutheran molecules, with specific monoclonal antibodies by indirect immunofluorescence by flux cytometry. In both groups there was a significant decrease in expression of LFA-1 and VLA-4 molecules MNC and of LFA-1 in neutrophils of patients basal state; decrease in L-selectine molecule expression in MNC and in patients in basal state. Increase of IACM-1 (CD54), CD34 and VCAM-1 (CD106) in MNC and in peripheral blood of basal patients shows the presence of a permanent leukocyte activation state determined by the continuous subclinical inflammation. The significant increase of ICAM-1 in neutrophils and CD34 and VCAM-1 in peripheral blood in both groups of patients with a higher increase of VCAM-1 in patients in crises, shows the monocyte, lymphocyte , neutrophils, and of endothelial cells during the PVOC and the release of these latter to periphery. We note a higher expression of LFA-1, L-selectine and ICAM-1 molecules in neutrophils of patients with PVOC and a significant increase of CD18 molecule in MNC of patients with PVOC that may be explained by monocyte activation in vaso-occlusive phenomenon.

Predicted and verified distributions of Ateles geoffroyi and Alouatta palliata in Oaxaca, Mexico.

Primate conservation requires a better knowledge of the distributions and statuses of populations in both large areas of habitat and in areas for which we currently have no information. We focused on spider monkeys (Ateles geoffroyi) and howler monkeys (Alouatta palliata) in the state of Oaxaca, Mexico. This Mexican state has protected large tracts of forest, and has historical records for both primates, although very little is known about them. To update our knowledge of the distributions of these primates and identify potential areas in which they are present, we modeled their geographic distributions by characterizing their ecological niches using the genetic algorithm for rule-set production (GARP), performed interviews and carried out field surveys. The predicted distributions, surveys and interviews indicate that the distributions of these primates are restricted to northeastern Oaxaca. The results suggest that spider monkeys occupy a wider area and elevational range than howler monkeys. Throughout that range there is a wide variety of suitable habitats for these primates. Most of the sites where monkeys were recorded in the field are not officially protected and there was evidence of hunting and habitat destruction. It is important to improve protection, economic alternatives and environmental education as we move towards an integral solution for the conservation of these species. Validation of the GARP model was done for A. geoffroyi, since we had obtained enough field data for this species; this validation indicated that the predicted distribution of the species was statistically better than expected by chance. Hence, ecological niche modeling is a useful approach when performing an initial assessment to identify distribution patterns, detecting suitable areas for future exploration, and for conservation planning. Our findings provide an improved basis for primate conservation and productive fieldwork in Oaxaca.

Vulnerabilidad espacial al dengue: una aplicación de los sistemas de información geográfica en el municipio Playa de Ciudad de La Habana / Spatial vulnerability to dengue: an applications of the geographic informations systems in Havana city

Durante la década de los años noventa, se ha extendido el uso de los sistemas de información geográfica en salud (SIG). Por otra parte el dengue reemerge con particular intensidad en este período, y progresa el uso de las herramientas SIG en su estudio. La presente investigación tiene como objetivos identificar la diferenciación espacial de la vulnerabilidad para la ocurrencia de dengue en el municipio Playa de Ciudad de La Habana, y contrastar los estratos identificados con la espacialidad de los casos notificados durante el brote reportado en el año 2000. Se confeccionó una base de datos digital a escala 1: 25 000, que define como polígonos las manzanas, y como atributos aquellos asociados a los macrofactores y microfactores de transmisión, y a la introducción del virus. Para los análisis espaciales se emplearon los softwares Mapinfo 5.0., Sig Epi 2000 y el SPSS 8.0. Se determinaron 3 grupos de manzanas según similitud de los valores de las variables, categorizadas en estratos espaciales de vulnerabilidad a la transmisión, como poco vulnerable, medianamente vulnerable y muy vulnerable. Se comprueba la solidez de los hallazgos, por su asociación con la espacialidad de los casos notificados

Respuesta humoral específica en ratones Balb/c inoculados con una librería genómica de expresión de Trypanosoma cruzi / Specific humoral response in Balb/c mice inoculated with a genome library of expression of Trypanosoma cruzi

A genomic expression library of Trypanosoma cruzi (T. cruzi) was made using plasmid pcDNA3 as a vector, with which male mice from the Balb/c isogenic line were intramuscullary inoculated. It was used a positive control group that was administered soluble antigens of T. cruzi. Other 2 groups received genomic and plasmid DNA, respectively. One group was not immunized. Weekly blood samples were obtained from all the animals until the fourth week and 2 weeks after reimmunization to study the response of specific antibodies against the microorganism antigens by an indirect immunoenzymatic assay (ELISA). It was observed a significant increase of specific antibodies in the animals reimmunized with 50 micrograms of the library, as well as in the group immunized with soluble antigens of T. cruzi.