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Blood safety has been of paramount concern worldwide over the last decades, and Latin America and Mexico are no exception. Factors of utmost importance include the use of highly efficient screening tests and the encouragement of voluntary donation. This review summarizes the current situation in Latin America and particularly in Mexico with respect to these key issues. Except for some specific regions, there is a lack of progress of voluntary donation in Mexico compared with other Latin American countries. A more efficient voluntary donation system could provide donors with lower prevalence of infectious agents such as human immunodeficiency, hepatitis B, and hepatitis C viruses. In Latin America, and specifically in countries such as Argentina, Brazil and Nicaragua, voluntary donation and blood safety are strongly encouraged. However, to date, in Mexico there has not been a specific blood safety project because of fragmentation of the health system model with structural differences among organisations. Although national policies are established to grant health coverages in Mexico, blood safety is still limited and outdated because of oversights in technical fields and regulations. Individual molecular biological tests for donor screening have recently been incorporated into the Mexican national regulations. Although the routine use of these tests as part of effective donor screening is still not compulsory, it is enabling a progressive improvement of blood safety.

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BACKGROUND: Ischemic heart disease, cerebrovascular accident, and venous thromboembolism have the presence of a thrombotic event in common and represent the most common causes of death within the population. OBJECTIVE: Since Schiff base copper(II) complexes are able to interact with polyphosphates (PolyP), a procoagulant and potentially prothrombotic platelet agent, we investigated the antiplatelet aggregating properties of two novel tridentate Schiff base ligands and their corresponding copper( II) complexes. METHODS: The Schiff base ligands (L1) and (L2), as well as their corresponding copper(II) complexes (C1) and (C2), were synthesized and characterized by chemical analysis, X-ray diffraction, mass spectrometry, and UV-Visible, IR and far IR spectroscopy. In addition, EPR studies were carried out for (C1) and (C2), while (L1) and (L2) were further analyzed by 1H and 13C NMR. Tests for antiplatelet aggregation activities of all of the four compounds were conducted. RESULTS: X-ray diffraction studies show that (L1) and (L2) exist in the enol-imine tautomeric form with a strong intramolecular hydrogen bond. NMR studies show that both ligands are found as enol-imine tautomers in CDCl3 solution. In the solid state, the geometry around the copper(II) ion in both (C1) and (C2) is square planar. EPR spectra suggest that the geometry of the complexes is similar to that observed in the solid state by X-ray crystallography. Compound (C2) exhibited the strongest antiplatelet aggregation activity. CONCLUSION: Schiff base copper(II) complexes, which are attracting increasing interest, could represent a new approach to treat thrombosis by blocking the activity of PolyP with a potential anticoagulant activity and, most importantly, demonstrating no adverse bleeding events.

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BACKGROUND: Postprandial triglyceridemia may transitory affect the structure of HDL subclasses and probably their antiatherogenic properties but little is known in this field. We analyzed the HDL subclasses lipid content along postprandial period. METHODS: Fifteen metabolic syndrome (MS) patients and 15 healthy controls were enrolled. HDL were isolated from plasma samples obtained at fasting and every 2-h up to 8-h, after a 75-g fat meal. Cholesterol (C), triglycerides (TAG), and phospholipid (Ph) plasma concentrations of five HDL subclasses were determined by densitometry of electrophoresis gels enzymatically stained. RESULTS: The increase of postprandial triglyceridemia expressed as the incremental area under the curve (iAUC) was twice in MS patients than in controls. Only large HDL2b-TAG were higher in MS than controls at 4, 6 and 8h after meal intake, whereas cholesterol of HDL2a, 3a and 3b were lower at 8h. HDL size distribution shifted towards large HDL and HDL3a-, 3b- and 3c-subclasses had a lower content of cholesterol (estimated by the C-to-Ph ratio) in subjects whose iAUC>289.5mgh/dl (n=15) in comparison with those subjects with iAUC below this cutoff point (n=15), independently of the MS status and fasting TAG. Triglycerides content of HDL subclasses changed only discreetly along the postprandial period, whereas paraoxonase-1 remained unchanged. CONCLUSIONS: A high postprandial triglyceridemia conditions the shift of HDL size distribution towards large particles and the decrease of cholesterol in HDL3 subclasses. These data demonstrate that postprandial hypertriglyceridemia contributes to a transitory hypoalphalipoproteinemia that may increase the risk of cardiovascular disease.

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There is a current tendency to develop and apply environmentally friendly techniques that meet the requirements of green analytical chemistry as an alternative to conventional analytical methods. For toxicity evaluation, these alternatives may be found in bioassays such as Tradescantia. This technique, developed in the 1980s, is highly sensitive to evaluate environmental mutagens, simple and cheap. In this paper, the sensibility of both the Tradescantia micronucleus bioassay (Trad-MCN) and the Tradescantia stamen hair bioassay (Trad-SH) were studied for carbaryl, dimethoate and iprodione, common agricultural and domestic pesticides that are currently used in Chile, which have never been tested with such bioassays. Biomonitor exposures were performed by capillary absorption for each individual pesticide over a wide range of concentrations, from maximum residue limits (trace levels) up to the application dose in agricultural fields. In addition, the organochloride 4,4'-DDE was included but only in the concentration range from 0.01mgL-1 to 1mgL-1, mimicking residue concentrations since it is not a commercial product but, rather, the main breakdown product of the persistent organochloride pesticide 4,4-DDT, whose use was discontinued in Chile in the 1980s. The Trad-MCN bioassay revealed a significant increase in micronucleus frequency at the early tetrads of meiotic pollen mother cells of the biomonitor Tradescantia pallida var. purpurea, induced by 4,4'-DDE (for 1mgL-1), dimethoate (for 40mgL-1, 200mgL-1, 400mg/L-1) and carbaryl (for 889mgL-1). Iprodione did not generate any significant change at the tested concentration. Meanwhile, the Trad-SH bioassay was carried out by analysis of the phenotype variations of the stamen hair cells of the Tradescantia clone KU-20 for the same pesticides and doses. This bioassay was not sufficiently sensitive for toxicity evaluation of most of the pesticides tested, with exception of dimethoate in low doses (2 and 5mg/L-1).

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Acute coronary syndromes (ACS) may be triggered by acute infections. Systemic production of interferon gamma (IFN-γ) is induced during infection and regulates the production of matrix metalloproteinases (MMPs) and their inhibitors (TIMPs), both important in plaque stability. This study evaluates the effect of IFN-γ on the MMPs/TIMP-1 ratio in cultured monocytes from 30 patients with stable coronary artery disease (CAD), 30 with unstable angina (UA) or non-ST-segment elevation myocardial infarction (NSTEMI), and 30 healthy blood donors. Supernatant concentrations of MMP-1, -2, -9, and TIMP-1 were measured by enzyme-linked immunoassays. Basal concentration of MMP-1 and TIMP-1 was similar between groups, while MMP-2 was higher in healthy individuals and MMP-9 in patients with UA/NSTEMI. Upon IFN-γ stimulation, MMP-9 secretion increased in all groups, while TIMP-1 decreased only in patients with CAD, which in turn result in a strikingly elevation in their mean MMP-9/TIMP-1 ratio. MMP-1/TIMP-1 and MMP-2/TIMP-1 ratios were <1.0 in basal conditions and after stimulation in all groups. Our results suggest that nonstimulated monocytes from patients with stable CAD show a similar behavior than those from healthy individuals. However, stimulation with IFN-γ induces an increase on the MMP-9/TIMP-1 ratio as high as that found in patients with ACS. Thus, it may bring biological plausibility to the association between acute infections and the development of ACS.

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Transfusion-related acute lung injury (TRALI) is a syndrome characterized by acute respiratory distress following the transfusion of blood components. The pathophysiological hallmark of TRALI is increased pulmonary microvascular permeability. Several reports demonstrate that the majority of TRALI cases are precipitated by transfusion of donor antibodies directed against HLA (human leukocyte antigens) or HNA (human neutrophil antigens) expressed on the neutrophils' surface of the recipient. This antibody-antigen interaction is thought to directly cause neutrophils activation and release of cytotoxic agents, with subsequent endothelial damage and capillary leak. Following plasma transfusion is an important and underreported adverse event. Some blood centers have limited the collection of plasma from female donors due to their propensity for developing anti HLA antibodies after pregnancy.

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It is known that residential wood combustion (RWC) is an important source of fine particle emissions. The purpose of this work was to characterize the chemical composition of the particulate matter present in the Temuco urban atmosphere during winter, specifically the polycyclic aromatic hydrocarbon (PAH) profile, because PAHs are considered to be among the key compounds in particulate matter toxicity. During the 2008 winter monitoring campaign, samples of particulate matter with aerodynamic diameters of < or = 10 (PM10) and < or = 2.5 (PM2.5) microm were taken on days with contamination episodes. Sixteen U.S. Environmental Protection Agency (EPA) PAH compounds were extracted with toluene and determined by gas chromatography-mass spectrometry (GC-MS). The results show that phenantrene was the predominant compound associated with particulate matter at a concentration range between 300 and 600 ng m(-3), 18 times higher than the second most abundant PAH compound. High-molecular-mass compounds such as dibenz[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3,c,d]pyrene were also found, but they were minorities in the set. It was recognized from the PAH concentration ratios of the Temuco atmospheric aerosol that the main contamination source was in fact residential wood combustion; although not all the concentration ratios evaluated match the reported reference values, probably due to the kind of biomass used, the characteristics of Chilean heating appliances and climate.

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Esta investigación, desde una perspectiva holística, buscó conocer en las familias de niños que asisten a los comedores comunitarios en un barrio capitalino de Santiago del Estero, Argentina, la red de apoyo que utilizan y los recursos que obtienen para poder resolver sus necesidades cotidianas. Es un estudio cuanticualitativo. Los datos fueron recolectados por encuestas parcialmente estructuradas y entrevistas en profundidad. El análisis de los datos se basó en identificación de frecuencias absolutas y relativas. Para los datos cualitativos se usó el referencial fenomenológico heideggeriano. Los resultados indican que 48 por ciento de las familias tienen 4 a 5 elementos en la red de apoyo; 91 por ciento buscan alimentos, 84 por ciento salud y el 73 por ciento trabajo; esta reducida red les genera importantes dificultades al momento de satisfacer sus necesidades básicas. La falta de trabajo y baja escolaridad son los principales condicionantes de su aislamiento social.

This investigation, from a holística perspective, sought to better understand the network of support that families with children who eat in communitarian dining rooms in a capital district Santiago of the Estero, Argentina, use and the resources that they obtain to be able to solve their daily necessities. This is a quanti-qualitative study. The data were collected by semi-structured surveys and in depth interviews. The data analysis was based on identification of absolute and relative frequencies. For qualitative data, the Heidegger phenomenology reference was used. The results indicate that 48 percent of the families have 4 to 5 elements in their support network; 91 percent look for food, 84 percent health, and 73 percent work. This reduced network generates important difficulties for them at the time of satisfying basic necessities. The lack of work and low schooling are the main conditioners of their social isolation.

Esta investigação, em uma perspectiva holística, buscou conhecer nas famílias de crianças que freqüentam refeitórios comunitários em um bairro da cidade Capital de Santiago del Estero, Argentina, a rede de apoio social que utilizam e os recursos que obtém para poder resolver suas necessidades cotidianas. É um estudo quanti-qualitativo. Os dados foram coletados por pesquisa semi-estruturada e entrevista em profundidade. O processo de análise dos dados se baseou em identificação de freqüências absolutas e relativas. Para os dados qualitativos se utilizou o referencial fenomenológico heideggeriano. Os resultados indicaram que 48 por cento das famílias têm 4 a 5 elementos na rede de apoio; 91 por cento buscam alimentos, 84 por cento, saúde e 73 por cento, trabalho. Essa reduzida rede gera dificuldades importantes no momento de satisfazer suas necessidades básicas. A falta de trabalho e baixa escolaridade são os principais condicionantes de seu isolamento social.

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Background. Previous reports have shown that undernourished children with acute lymphoblastic leukemia (ALL) have a poorer long-term survival as compared withchildren with normal nourishment status. It has been shown that both the relapse and mortality rates of undernourished children with ALL are higher during the continuation phase of the chemotherapy and are apparently related to a poor tolerance of ablative chemotherapy. No previous artichles have analyzed the aerly mortality rate of these patients. Methods. We carried out a case-control study, and have studied the effect of severe malnutrition on the mortality of 17 children with ALL during the initial induction-to-remission phase of the treatment. These 17 cases were compared with 76 controls who had survived at least the phases of induction and consolidation. Results. It was found that the chance of dying during the initial phase of the treatment was 2.6 times higher (confidence interval 95 percent: 0.55-11.89) in undernourished children with ALL than in those children with normal nourishment status. The risk of death increades with the severity of undernorisment (p= 0.04). Conclusions. These data confirm the prognostic value of malnutrition in children with ALL and suggest that undernourishment may also influence aerly mortality during the induction-to-remission phase of the treatment

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Background. The aim of this paper is to present the epidemiological characteristics of time, subject and place of lymphomas in children residing in Mexico City, Mexico (MC). Methods. The type of study was a retrospective hospital survey. All records of children with lymphomas registered between 1982 and 1991 at the main hospitals that treat children with cancer in MC were reviewed. Neoplasms were classified into Hodgkin's disease (HD) and non-Hodgkin's lymphomas (NonHL). Trend and incidence by sex, age and area of residence in MC were evaluated. Time of diagnosis, as well as parental occupation and educational level, were registered. Results. A trend was only observed for HD in the total group (r:0.62; P=0.05). In 1991, incidence for HD was 6.12 (rates x 10 at 6) and 3.87 for NonHL. The highest average incidence was found in children 5-9 years of age (5.40= for HD, and in the age groups of 1-4 and 5-9 (3.10 and 3.33, respectively), for NonHL. Incidence was higher among boys for both lymphoma categories, but the male-to-female ratio was much higher in HD. Time of diagnosis, incidence in terms of place of residence, and parental educational level and occupation also differed from one lymphoma category to the other. Conclusion. The epidemiology of HD is different from that of NonHL, both showing a pattern similar to that of Latin American children

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La anemia es un problema frecuente en la consulta diaria. Se presenta cuando el nivel de hemoglobina es inferior al considerado como límite normal, de acuerdo a: edad, sexo y altura sobre el nivel del mar. La medición de la hemoglobina y el examen del frotis de sangre periférica proporciona información necesaria para identificar los principales tipos de anemia. El conocer las causas prevalentes de la anemia puede ayudar a simplificar el estudio y establecer las causas en los grupos de población vulnerable. Fisiopatogenia de la anemia. La constancia en la cifra de hemoglobina dentro de los límites de variación en personas sanas, alimentadas adecuadamente, implica la existencia de un equilibrio entre la remoción diaria de glóbulos rojos que alcanzaron el límite de su vida y la formación de la misma cantidad por día en la médula ósea. Este equilibrio depende de los requerimientos de oxígeno a nivel de los tejidos y de la acción de la eritropoyetina, a condición desde luego de que la médula sea normal, anatómica y funcionalmente, que se cuente con los nutrientes requeridos y que la persona no padezca una condición patológica que interfiera con la eritropoyesis. La clasificación fisiopatogénica es útil y permite determinar el origen de la anemia, tomando en cuenta el aspecto etiológico. La anemia por deficiencia de hierro se desarrolla en pacientes quienes se han agotado previamente las reservas de hierro; es la causa más común de anemia en el mundo. Etiopatogenia: a) ingesta inadecuada; b) disminución en la absorción y en su utilización y c) sangrado crónico. Tratamiento de anemia: identificar y corregir la causa, transfundir paquete globular ante cifra de hemoglobina menor a 5 g/dL

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Las histiocitosis son un grupo de desórdenes clínicos que se presentan en los niños que desde las primeras publicaciones han representado dificultad para el diagnóstico y tratamiento y que hasta la fecha se ha superado al aplicar mejor tecnología para su estudio. El término de malignidad se ha dado por el conocimiento de clonalidad y curso clínco agresivo. El histiocito forma parte del sistema fagocítico mononuclear y del sistema efecto de inmunorregulación (monocito-macrófago y células dendríticas-células de Langerhans). Por tanto, los criterios de clasificación de los síndromes histiocíticos están caracterizados por proliferación reactiva o neoplásica tanto de la línea de los macrófagos como de las células dendríticas/células de Langerhans; tal clasifiación es propuesta por el grupo de estudio de la Sociedad Internacional de Histiocitosis. La anterior denominación de histiocitosis X era relacionada a entidades clínicas y la letra X fue usada como un distintivo de desconocimiento. Los avances en el estudio de las histiocitosis de células de Langerhans fueron la demostración de gránulos de Birbeck que son cuerpos de inclusión visibles (ME) y la positividad al antígeno CD1a. Otro aspecto es la extensión: limitado y extensa o multisistémico; en el pronóstico interviene la edad, el comportamiento progresivo y disfunción orgánica. La estrategia de tratamiento es de acuerdo a la extensión y si presenta disfunción orgánica se debe evaluar si pertence al grupo de alto riesgo para lo cual existen diversos protocolos de quimioterapia. Otro avance en la histiocitosis de células de Langerhans es el posible papel del sistema inmune, la clonalidad, las citoquinas y los virus en su etiopatogenia

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Introducción. La tiflitis es una colitis necrozante con inflamación del ciego en pacientes neutropénicos, usualmente diagnosticada en la autopsia. Material y métodos. identificamos 18 niños hospitalizados en el Hospital Infantil de México Federico Gómez en un período de 10 años, con presencia de fiebre, dolor e hipersensibilidad abdominal sugestiva de tiflitis neutropénica. Resultados. Ocho de los 18 pacientes tenían evidencia radiológica de tiflitis en las radiografías de abdomen. Todos los pacientes presentaron neutropenia al momento del diagnóstico y 9 tenían bacteriemia documentada. Los 18 pacientes fueron tratados con diversos antibióticos, 4 de ellos sometidos a cirugía y 1 a colonoscopia. Once pacientes murieron, 10 se mejoraron médicamente y 1 quirúrgicamente. En orden de frecuencia, la tiflitis fue identificada en 9 pacientes con leucemia aguda no linfoide, en 6 con leucemia aguda linfoide; en 1 con anemia aplásica, neutropenia cíclica y carcinoma renal, respectivamente. Sólo 4 pacientes recibieron factor estimulador de colonias de granulocitos; y en todos los pacientes que sobrevivieron se observó un aumento de leucocitos polimorfonucleares a más de 500/mm3 documentado entre el cuarto y el décimosexto día de manejo médico y/o quirúrgico. Conclusiones. Recomendamos que ante un paciente con fiebre y neutropenia, con dolor e hipersensibilidad abdominal, además de datos como diarrea hematemesis se debe plantear como diagnóstico tiflitis neutropénia e instaurarse el manejo general y específico que incluye la valoración quirúrgica

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Se diseñó un estudio comparativo entre niños con anemia aplástica y pacientes con otro tipo de padecimiento, encamados en el hospital. En el estudioo, fue posible observar, que los niños con anemia aplástica procedian de zonas rurales a diferencia de los niños controles que procedian de zonas urbanas marginales. Los resultados en las pruebas señalaron la presencia de un daño y/o disfunción cerebral en los niños con anemia aplástica, además de un cociente intelectual menor en la prueba de Weschler en relación al grupo testigo. Fue posible observar una menor sintomatología de tipo psicológico antes del padecimiento, así como una mejor autoimagen del niño con anemia aplástica en relación al grupo testigo. Sin embargo, no es posible decir si las alteraciones neurológicas observadas en el grupo con anemia aplástica, se presentaron antes o después del padecimiento y si las diferencias en el cociente intelectual entre los grupos son el resultado de las diferencias entre los ambientes socioeconómicos a los que pertenecen cada grupo

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En un estudio previo se encontró en las familias de los niños con anemia aplástica, predominio de hogares no integrados, pobreza y alimentación deficiente, por lo que se planteó confirmar o rechazar estos hallazgos mediante un muestro más adecuado, de las familias testigo. Por cada paciente que ingresó al hospital con anemia aplástica, se eligió uno por azar que hubiera ingresado al mismo tiempo, con otro diagnóstico y que comparable en cuanto a sexo y edad. Se explicó a las dos familias el objeto del estudio y los autores investigaron en las dos, características de residencias respectivas, de los padres y de su unión, de la alimentación y de los enfermos desde el punto de vista nutricional. Se estudiaron 30 familias de cada grupo y en los de anemia aplástica se encontró predominio significativo de: residencia proletaria en área no urbana; ausencia de drenaje y de baño individual; fecalismo y convivencia con animales; padres analfabetos; padres que trabajan como campesinos o albañiles; ingestión deficiente de carne, leche, huevo, plátano, naranja, otras frutas y verduras; retraso en la edad ósea y albúmina sérica baja; calificaciones inferiores a 8 y frecuencia de reprobados (paciente y hermanos) y exposición a agentes químicos. Estos datos sugieren que la anemia aplástica en México tiene una etiología multifactorial

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Se presentan dos hermanas con antecedentes de consaguinidad en los padres. Ingresaron al hospital por presentar hepatosplenomegalia y se les efectuó el diagnóstico de linfohistiocitosis hemofagocítica familiar. La primera de las pacientes falleció antes de recibir tratamiento y la segunda recibió tratamiento con vincristina, metrotrexate y prednisona. Se hace una revisión del cuadro clínico e histológico, así como una discusión del diagnóstico diferencial de esta rara enfermedad con otros desórdenes del sistema macrofágico

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Se seleccionó un grupo de 94 mujeres embarazadas sanas, residentes a 2,650 metros sobre el nivel del mar, con promedio de 25 años de edad (D.E.: 7.1), que cursaran de la I a la IV gesta, de marzo a octubre de 1981. El grupo aceptó una alimentación adecuada, suplemento de hierro por vía parenteral, complejo B y ácido fólico. Se aceptaron para el estudio 48 niños en buenas condiciones nutricionales, productos de embarazos normales y partos eutócicos. Los niños fueron alimentados con leche materna. A partir de la primera semana se dividieron en dos grupos: Grupo 1 con suplemento postnatal de hierro y grupo II sin suplemento de hierro postnatal. Se les efectuaron determinaciones de: hemoglobina, hematócrito, eritrocitos, VCM, reticulocitos, leucocitos con cuenta diferencial (a 200 células) y plaquetas, al nacimiento, con muestras de sangre del cordón umbilical y en muestras obtenidas por punción capilar a las 24 y 72 horas y primera, segunda, tercera, cuarta, sexta y octava semanas de vida, lo cual requirió visita domiciliaria para valoración clínica, somatometría y control de la alimentación. La variación de peso y talla se encontró dentro de los límites esperados. Se compararon los resultados obtenidos para la serie roja con los informados en varios países y se observaron diferencias aparentemente relacionadas con los requisitos de selección para las madres y de los niños, la alimentación, la administración de suplementos, las técnicas de laboratorio y la altura sobre el nivel del mar. Se encontró un estudio realizado a nivel del mar con criterios de selección, de alimentación, de administración de complementos y de técnicas de laboratorio semejantes y se decidió la comparación, encontrando que los valores de hemoglobina y hematócrito a 2.650 metros sobre el nivel del mar, son más elevados y que las diferencias son significativas a partir de la cuarta semana para la hemoglobina y de la tercera semana para el hematócrito. Las cifras de leucocitos coinciden con las encontradas por otros autores. Se encontraron plaquetas con valores más altos, pero los resultados no son comparables por diferencia en los métodos de la laboratorio

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