Diabetic erythrocytes test by correlation coefficient.

Even when a healthy individual is studied, his/her erythrocytes in capillaries continually change their shape in a synchronized erratic fashion. In this work, the problem of characterizing the cell behavior is studied from the perspective of bounded correlated random walk, based on the assumption that diffractometric data involves both deterministic and stochastic components. The photometric readings are obtained by ektacytometry over several millions of shear elongated cells, using a home-made device called Erythrodeformeter. We have only a scalar signal and no governing equations; therefore the complete behavior has to be reconstructed in an artificial phase space. To analyze dynamics we used the technique of time delay coordinates suggested by Takens, May algorithm, and Fourier transform. The results suggest that on random-walk approach the samples from healthy controls exhibit significant differences from those from diabetic patients and these could allow us to claim that we have linked mathematical nonlinear tools with clinical aspects of diabetic erythrocytes' rheological properties.

Evaluación de alteraciones hemorreológicas en pacientes hipertensos / Hemorheological alterations in hypertensive patients

El objetivo de este trabajo fue investigar el perfil de viscosidad sanguínea y evaluar la influencia de factores plasmáticos ( fibrinógeno) y celulares ( agregación eritrocitaria ) en un grupo de pacientes hipertensos comparados con un grupo de paciente normotensos. Se trabajó con sangre anticoagulada de pacientes hipertensos no diabéticos (n=3) e indivíduos sanos (n=40). La viscosidad plasmática y de sangre entera se determinaron con un viscosímetro cono-plato. La agregación eritrocitaria se estudió por observación microscopia de los agregados y cuantificación a través de un parâmetro de forma denominado ASP ( Aggregation Shape Parameter), definido como la relación de área proyectada respecto al perímetro. El fibrinógeno se determino con un coagulómetro por el método de Clauss. Los valores de viscosidad de sangre entera resultaron significativamente aumentados en los pacientes hipertensos respecto de los normales para todas las velicidades estudiadas. Los valores de viscosidad plasmática solo presentaron diferencia significativas a bajas velocidades de corte (1.15 a 11.56 seg •1) . Los pacientes hipertensos presentaron agregados amorfos e irregulares, lo que se refleja en los valores alterados de ASP, significativamente mayores (p<0.001) en paciente hipertensos (0.69± 0.11) respecto de los indivíduos normales ( 0.25± 0.12). Los valores de fibrinógeno resultaron ligeramente superiores en los pacientes hipertensos respecto del grupo control (p< 0.01). Numerosos parámetros hemorreológicos juegan un papel importante en la patogénesis de la hipertensión. Entre estos factores hemorreológicos, valores parâmetros podrían estar en la hipertensión ( hematrocito, fibrinógeno plasmático, deformabilidad y agragación eritrocitaria , viscosidad sanguínea y plasmática). En este trabajo, se pudo demostrar anormalidades en la agregación eritrocitaria, detectada por los valores de ASP que podría estar involucrado en las complicaciones vasculares de la hipertensión.

Alterations to complex viscoelasticity of erythrocytes during storage.

Rheological alterations produced during the storage of human erythrocytes were studied by means of in vitro viscoelastic parameters. Weekly aliquots of packed red blood cells (PRBC) and whole blood (WB) stored in CPD-adenine were studied for 35 days. Samples were analyzed in Erythrodeformeter both in stationary and oscillating regime. We found that erythrocyte deformability index and all complex viscoelastic parameters are modified by storage. Plasma viscosity and blood viscosity were measured in a cone/plate Viscometer. Blood viscosity at high shear rates shows variations related to conservation time, which are in correlation with the variations observed in the erythrocyte deformability index. Blood viscosity at low shear rate decreases during storage. Rheological tests would demonstrate some alterations in the structural properties of erythrocyte stored as PRBC. These alterations are less than those found in WB. We conclude that plasmatic proteins play a predominant role in the alteration of rheological behavior of erythrocytes during their storage. Consequently, it is important to evaluate not only cellular components but also plasma.

[Abnormal glycosylation of soluble ABH antigens in tumors of the urinary tract]. / Glicosilación anormal de antígenos ABH solubles en patologías tumorales del tracto urinario.

OBJECTIVE: To determine the secretor expression in patients with bladder cancer, adenoma of the prostate and normal subjects. METHODS: The secretor character was determined in saliva of normal subjects (n = 40), patients with bladder cancer (n = 61) and adenoma of the prostate (n = 44) by the technique of hemoagglutination inhibition. RESULTS: 80% of the normal subjects were found to be secretors, which is in agreement with the data reported in the literature. Only 23 (37.71%) of the patients with bladder cancer were secretors and 24 (54.54%) of the patients with prostate adenoma expressed the secretor gene. CONCLUSIONS: The expression of soluble antigens decreased in patients with bladder cancer or prostate adenoma in comparison to the normal subjects. Deletion of ABH antigens in the membrane of tumor cells has been reported in other studies. This lack of expression results from a genetic alteration in the clones involved in tumor pathology. The decrease in soluble antigens in the patient groups analyzed might be due to the same mechanism of genetic alteration that could involve non tumor tissues. Most of the cancers in humans originate in epithelial cells and the changes in blood group antigens constitute an important aspect in tumor immunology.

Evaluation of red blood cell aggregation in diabetes by computerized image analysis.

Red blood cell (RBC) aggregation has been widely studied and its importance is well established in the rheology of microcirculation. RBC aggregation is a major factor responsible for the flow properties of blood. Increased RBC aggregation has been observed in several pathological states. Therefore, the measurement of erythrocyte aggregation is rheologically important for quantifying flow abnormality in pathological conditions. Normal RBC under low flow or at rest form rouleaux aggregates, while abnormal RBC aggregation may lead to the formation of irregular aggregate structures, which may be induced by cell-associated factors (reduced membrane sialic acid levels) but also by extracellular factors. The main objective of the present investigation was to study RBC aggregate morphology in diabetic patients, using direct microscopic observation and numerical processing of recorded digitized images. Blood samples were obtained from 20 diabetic patients and from 15 normal control subjects. The aggregate morphology was quantified by the so-called Aggregate Shape Parameter (ASP) defined as the ratio of the aggregate projected area to its square perimeter. ASP appeared significantly higher (p < 10(-5)) in diabetic patients (0.65 +/- 0.18) than in normal controls (0.28 +/- 0.15). This rheo-optical method based on the theoretical model for rouleaux aggregates provides a useful reference for measuring deviations of RBC aggregate morphology. Increased aggregation of RBC resulting from a decreased sialylation of glycophorins may be an important factor in the development of vascular diseases and in the microcirculation impairment.

[Deletion of ABH antigens in urine sediment cells from patients with prostatic adenoma]. / Deleción antigénica ABH en células de sedimento urinario de pacientes con adenoma de próstata.

OBJECTIVE: This study was conducted to analyze ABH antigenic expression in urinary sediment of patients with benign prostatic hyperplasia (BPH) before and after deobstructive surgery. METHODS/RESULTS: The agglutination inhibition technique was utilized to determine the ABH antigenic expression in urinary sediments of 30 healthy subjects and 34 patients with BPH. The presence of neoplastic cells was also determined in urinary sediments of the patients by Papanicolaou's stain. These studies were performed before and 12 months after surgery. Membrane antigen expression was found in 100% of the healthy subjects and in only 50% of the patients with BPH before surgery. Only 25 patients returned for control evaluation after surgery. Of these, 17 were positive and of the remaining 8 patients who were negative preoperatively, only one continued to be negative. Urine cytology demonstrated progression to malignancy in this patient. CONCLUSIONS: Determination of ABH antigenic expression appears to be able to identify premalignant conditions and could be a useful complementary diagnostic method to cytology.

Evaluation of red blood cell aggregation in diabetes by computerized image analysis

Red blood cell (RBC) aggregation has been widely studied and its importance is well established in the rheology of microcirculation. RBC aggregation is a major factor responsible for the flow properties of blood. Increased RBC aggregation has been observed in several pathological states. Therefore, the measurement of erythrocyte aggregation is rheologically important for quantifying flow abnormality in pathological conditions. Normal RBC under low flow or at rest form rouleaux aggregates, while abnormal RBC aggregation may lead to the formation of irregular aggregate structures, which may be induced by cell-associated factors (reduced membrane sialic acid levels) but also by extracellular factors. The main objective of the present investigation was to study RBC aggregate morphology in diabetic patients, using direct microscopic observation and numerical processing of recorded digitized images. Blood samples were obtained from 20 diabetic patients and from 15 normal control subjects. The aggregate morphology was quantified by the so-called Aggregate Shape Parameter (ASP) defined as the ratio of the aggregate projected area to its square perimeter. ASP appeared significantly higher (p < 10(-5)) in diabetic patients (0.65 +/- 0.18) than in normal controls (0.28 +/- 0.15). This rheo-optical method based on the theoretical model for rouleaux aggregates provides a useful reference for measuring deviations of RBC aggregate morphology. Increased aggregation of RBC resulting from a decreased sialylation of glycophorins may be an important factor in the development of vascular diseases and in the microcirculation impairment.

Relación entre la expresión de antigenos ABH en cancer de vejiga y caracter secretor / The relationship between the expression of ABH secretor character

Existe amplia evidencia de que el cáncer está asociado con anormalidades en la regulación génetica expresada en la superficie de la membrana celular. El 80 por ciento de los individuos son capaces de secretar los antígenos ABH en saliva y otras secreciones. La presencia de estas sustancias está controlada por un gen que puede adoptar dos formas alélicas: SE dominante y SE recesiva. El objetivo de este trabajo fue investigar la relación entre la expresión antigénica ABH en célkulas de descamación urotelial y el carácter secretor en pacientes con cáncer de vejiga. Se examinaron 33 pacientes con tumores de vejiga clasificados en superficiales y profundos y una población de 40 individuos normales. Se investigó el carácter secretor en saliva y la expresión de los antígenos ABH uroteliales en sedimentos urinario. Se empleó para estos estudios la técnica de inhibición de la aglutinación. En la población normal todos expresaron los antígenos ABH en células de sedimento urinario y sólo el 80 por ciento presentó dichos antígenos en sus secreciones. En los pacientes con cáncer de vejiga el 30,31 por ciento resultó no secretor y de ellos el 70 por ciento presentó deleción antigénica ABH en sedimento urinario con mayor incidencia de tumores profundos. Nuestros resultados indicarían que los pacientes con cáncer de vejiga no secretores desarrollarían tumores con mayor grado de infiltración respecto de los pacientes secretores

Hipertensión arterial y marcadores de grupo sanguíneo: asociación con el polimorfismo MN / Hypertension and blood group markers: association with MN polymophins

El objetivo de este trabajo fue analizar la relación entre presión arterial y marcadores genéticos eritrocitarios MN. La expresión de los antígenos M y N, se investigó por el Test de hemaglutinación en tubo, en una muestra de 164 individuos clasificados según presión arterial (normales e hipertensos) y fenotipo MN. De los 53 pacientes hipertensos, los porcentajes de cada fenotipo fueron: MN 56,6 por ciento,MM 34,0 por ciento, NN 9,4 por ciento mientras que entre los 111 individuos normotensos, la distribución resultó: MN 70,3 por ciento, MM 18,9 por ciento y NN 10,8 por ciento. De los resultados obtenidos en este trabajo, por la Prueba x², se concluye que sólo existe asociación entre el fenotipo MM y la hipertensión arterial. Diferencias en el patrón de agregación, debido a diferencias estructurales de los distintos grupos sanguíneos, podrían generar susceptibilidad a cambios en la viscosidad sanguínea, afectando el proceso de perfusión. El estudio de marcadores eritrocitarios, que pueden ser determinados por metodologías accesibles, podrían aportar datos de interés para la investigación de factores de riesgo en el desarrollo de la hipertensión arterial

[Evaluation of the kinetics of hemagglutination using a simple photometric technic]. / Evaluación de la cinética de hemaglutinación por medio de una técnica fotométrica simple.

A photometric technique to evaluate haemagglutination kinetic is presented in this paper. The technique applies the relative optical extinction (EO) produced on a light beam transmitted through a suspension of small particles (red blood cells and their agglutinates). The optical extinction decreases as the red cell agglutinates grow, giving a parametric estimate of the haemagglutination rate. Hence, optical extinction can be used to distinguish erythrocyte subgroups characterized by the differences appearing in the number of antigenic sites per cell. The paper describes the technique and gives the results of a set of experiments carried out on 90 samples constituted by 30 samples of A1 adults, 30 samples of non-A1 A adults and 30 samples of A newborns (cord red blood cells). Results show significative differences between subgroups. Parametric values such as the total relative optical extinction reduction (difference between the initial and the final values of EO) and the initial optical extinction rate are analyzed. Results from A newborn red cells show similar behaviour as the non-A1 A adult red cells and significative differences from A1 adult red cells. A correlation between parametric values and the number of antigenic sites per cell, as found in the literature, becomes evident.