RESUMO
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 Although national policies are established to grant health coverages in Mexico, blood safety is still limited and outdated because of oversights in technical fields and regulations.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.
Assuntos
Segurança do Sangue , Doadores de Sangue , Infecções por HIV/epidemiologia , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Humanos , América Latina/epidemiologia , México/epidemiologia , PrevalênciaRESUMO
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.
Assuntos
Complexos de Coordenação/química , Complexos de Coordenação/farmacologia , Cobre/química , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/farmacologia , Agregação Plaquetária/efeitos dos fármacos , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Bases de Schiff/química , Adulto JovemRESUMO
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.
Assuntos
Colesterol , Dieta Hiperlipídica , Hipertrigliceridemia/sangue , Lipoproteínas HDL/sangue , Lipoproteínas HDL/química , Período Pós-Prandial , Adulto , Idoso , Dieta Hiperlipídica/efeitos adversos , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
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.
Assuntos
Doença da Artéria Coronariana/metabolismo , Interferon gama/farmacologia , Metaloproteinase 9 da Matriz/metabolismo , Monócitos/efeitos dos fármacos , Monócitos/metabolismo , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Doença da Artéria Coronariana/diagnóstico , Feminino , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
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.
Assuntos
Reação Transfusional , Lesão Pulmonar Aguda/etiologia , Feminino , Humanos , Masculino , Fatores de Risco , Fatores SexuaisRESUMO
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
Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Adolescente , Leucemia-Linfoma Linfoblástico de Células Precursoras/complicações , Progressão da Doença , Indução de Remissão , Transtornos da Nutrição Infantil/etiologia , Estudos de Casos e Controles , PrognósticoRESUMO
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
Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Diretório , Incidência , Linfoma/epidemiologia , Estudos Retrospectivos , México/epidemiologiaRESUMO
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
Assuntos
Anemia/classificação , Anemia/diagnóstico , Anemia/etiologia , Anemia/fisiopatologia , Anemia/terapia , Hemoglobinas , Hemoglobinas/análise , /etiologiaRESUMO
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