Oral treatment and in vitro incubation with fructose modify vascular prostanoid production in the rat.

1.-- In the rat, a fructose-enriched diet induces hyperglycaemia, hypertriglyceridaemia, insulin resistance and hypertension; a model which resembles the human metabolic syndrome. 2.-- Prostanoids, metabolites of arachidonic acid, include vasoactive substances synthesized and released from the vascular wall that have been implicated in the increase of peripheral resistance, one of the mechanisms involved in the fructose-induced hypertension. 3.-- The aim of the present study was to: (i) analyse the effects of the in vitro incubation with fructose on the production and release of prostanoids in rat thoracic aorta and in rat mesenteric bed and (ii) compare the effects of incubation with those of the in vivo acute and chronic treatment of rats with fructose and with the combination of both in vivo and in vitro procedures. 4.-- Blood pressure, glycaemia and triglyceridaemia were significantly elevated in both 4- and 22-week fructose-treated groups. Meanwhile, body and heart weight as well as insulinaemia were similar between experimental animals and controls. 5.-- In aortae, 4 weeks of Fructose treatment did not modify the prostanoid pattern release, but in vitro incubation decreased prostacyclin (PGI(2)) production. However, after 22 weeks, fructose treatment and incubation exerted the same effect. 6.-- In mesenteric bed, after 4 weeks, the incubation and the combination of both procedures reduced the release of the vasodilators PGI(2) and PGE(2), while fructose treatment only diminished the PGE(2) release. On the contrary, the production of the vasoconstrictor thromboxane A(2) (TXA(2)) was enhanced by incubation and both the procedures. After 22 weeks, fructose treatment increased PGI(2) release, while it was reduced by incubation. The combination of both did not modify this peripheral resistance when compared with controls. Finally, incubation of tissues from treated rats increased the release of the vasoconstrictors, PGF(2alpha) and TXA(2). 7.-- In conclusion, the mesenteric bed, a resistance vascular bed, seems to be more sensitive than the aorta, a conductance vessel, to the effects of fructose on prostanoid production. This difference could be related to a more relevant role of resistance vessels in the regulation of peripheral resistance and consequently of blood pressure. The observed effects should contribute to a shift in the balance of the release of prostanoid in favour of vasoconstrictor metabolites. This phenomenon could be related to an increase in the peripheral resistance and the mild hypertension observed in the fructose-treated rats.

Punto de corte del indice: antigeno prostatico especifico libre (PSAI)/Antigeno prostatico especifico total (PSAt) / Free prostate specific antigen index (free PSA)/total prostate specific antigen (total PSA) accurate cutoff

Introduccion: El Psat es el marcador mas usado en patologias prostaticas: 10-30 por ciento circula como PSA I y 70-90 por ciento complejado (PSAc). Se ha propuesto que el indice PSAI/PSAt podria variar entre patologias benignas y malignas. Objetivo: El objetivo de este estudio fue establecer el mejor punto de corte para PSAI/PSAt en una poblacion con sospecha clinica-analitica de neoplasia prostatica. Material y metodos: a 136 varones con sospecha clinica-analitica de neoplasia prostatica se les realizo tacto rectal (TR) dosajes sericos de PSAt y PSAI, ecografia transrectal y biopsia. Se calculo sensibilidad y especificidad para diferentes puntos de corte PSAI/PSAt usando como metodo patron el resultado de la biopsia. Resultados: Todos los pacientes presentaron TR no sospechoso: en 47 individuos menores 60 años se detecto PSAt entre 2,50-9,99 ng/ml, 85 pacientes presentaron PSAI/PSAt mayor de 25 por ciento. La especificidad dignostica del indice PSAI/PSAt mostro una disminucion progresiva a medida que se aumento el punto de corte manteniendose los niveles de sensibilidad. Conclusiones: en la poblacion estudiada el indice PSAI/PSAt con mejor especificidad diganostica de CaP fue 15 por ciento en lugar del 25 por ciento empleado previamente

Punto de corte del indice: antigeno prostatico especifico libre (PSAI)/Antigeno prostatico especifico total (PSAt) / Free prostate specific antigen index (free PSA)/total prostate specific antigen (total PSA) accurate cutoff

Introduccion: El Psat es el marcador mas usado en patologias prostaticas: 10-30 por ciento circula como PSA I y 70-90 por ciento complejado (PSAc). Se ha propuesto que el indice PSAI/PSAt podria variar entre patologias benignas y malignas. Objetivo: El objetivo de este estudio fue establecer el mejor punto de corte para PSAI/PSAt en una poblacion con sospecha clinica-analitica de neoplasia prostatica. Material y metodos: a 136 varones con sospecha clinica-analitica de neoplasia prostatica se les realizo tacto rectal (TR) dosajes sericos de PSAt y PSAI, ecografia transrectal y biopsia. Se calculo sensibilidad y especificidad para diferentes puntos de corte PSAI/PSAt usando como metodo patron el resultado de la biopsia. Resultados: Todos los pacientes presentaron TR no sospechoso: en 47 individuos menores 60 años se detecto PSAt entre 2,50-9,99 ng/ml, 85 pacientes presentaron PSAI/PSAt mayor de 25 por ciento. La especificidad dignostica del indice PSAI/PSAt mostro una disminucion progresiva a medida que se aumento el punto de corte manteniendose los niveles de sensibilidad. Conclusiones: en la poblacion estudiada el indice PSAI/PSAt con mejor especificidad diganostica de CaP fue 15 por ciento en lugar del 25 por ciento empleado previamente(AU)

Shedding of immature germ cells.

The immature germ cells (IGC) constitute the highest percentage (90%) of nonsperm cells (NSpC) in ejaculates from fertile or infertile men. The objective of this study was to evaluate IGC concentration and the IGC/(IGC + Sp) ratio, in normozoospermia and dispermia. Normozoospermia from men with proven fertility (NPF). nonproven fertility (NNPF). dispermia (D) and semen samples with excessive shedding of immature germ cells (GI 1.7 x 10(6) to 5 x 10(6) IGC/mL and GII > 5.0 x 10(6) IGC/mL) were used in this study. The mean value +2 SD for the NNPF (1.7 x 10(6)/mL) and the value proposed by WHO (5 x 10(6)/mL) were employed to define GI and GII groups. IGC concentration is statistically different in the studied groups. The IGC/Sp ratio showed a significant difference only between the NNPF and the D. When comparing semen parameters (Sp/ejaculate. grade (a) motility and morphology) there was a highly significant difference between NNPF and GI and GII: no difference was found between GI and GII. While studying 200 cases of dispermias 83% showed a high shedding of immature germ cells. The cytological study of nonsperm cells and the count and identification of the immature germ cells could be used to evaluate the dispermic disorders.

[Soluble transferrin receptor and erythropoietin in chronic disease anemia with or without iron deficiency]. / Receptor soluble de transferrina y eritropoyetina en la anemia de los procesos crónicos con y sin deficiencia de hierro.

The regulation of transferrin receptor (RTF) is related to intracellular iron stores and with the soluble receptor is present in plasma. It has already been demonstrated that in iron deficiency anemia (IDA), receptor expression increases when iron stores decrease. In anemia of chronic diseases (ACD) it is difficult to establish the real iron status because of the influence exerted by inflammatory or infectious diseases on iron metabolism. We studied 30 healthy normal subjects and 42 anemic patients (hemoglobin less than 120 g/L) affected with ACD divided into two groups with and without iron deficiency, in order to establish the diagnostic value of measuring the soluble transferrin receptor (sRTF). We correlated erythropoietin (EPO) (as an erythropoietic stimulating factor) with the decreased hemoglobin values observed in both groups. The results were analysed with an ANOVA statistic test of one way analysis of variance, and there were no significant differences in sRTF values between the ACD groups with or without iron deficiency. The ratio log EPO vs hemoglobin showed a remarkably significant inverse correlation in both groups. We can conclude that sRTF levels are within the normal reference values in these patients and are not related to organic iron. Consequently, sRTF cannot be considered a good parameter for making a diagnosis of iron deficiency in chronic diseases.

Receptor soluble de transferrina y eritropoyetina en la anemia de los procesos crónicos con y sin deficiencia de hierro. / [Soluble transferrin receptor and erythropoietin in chronic disease anemia with or without iron deficiency]

The regulation of transferrin receptor (RTF) is related to intracellular iron stores and with the soluble receptor is present in plasma. It has already been demonstrated that in iron deficiency anemia (IDA), receptor expression increases when iron stores decrease. In anemia of chronic diseases (ACD) it is difficult to establish the real iron status because of the influence exerted by inflammatory or infectious diseases on iron metabolism. We studied 30 healthy normal subjects and 42 anemic patients (hemoglobin less than 120 g/L) affected with ACD divided into two groups with and without iron deficiency, in order to establish the diagnostic value of measuring the soluble transferrin receptor (sRTF). We correlated erythropoietin (EPO) (as an erythropoietic stimulating factor) with the decreased hemoglobin values observed in both groups. The results were analysed with an ANOVA statistic test of one way analysis of variance, and there were no significant differences in sRTF values between the ACD groups with or without iron deficiency. The ratio log EPO vs hemoglobin showed a remarkably significant inverse correlation in both groups. We can conclude that sRTF levels are within the normal reference values in these patients and are not related to organic iron. Consequently, sRTF cannot be considered a good parameter for making a diagnosis of iron deficiency in chronic diseases.

Oxidative damage, plasma antioxidant capacity, and glucemic control in elderly NIDDM patients.

A study of oxidative damage was made in elderly noninsulin-dependent diabetes mellitus (NIDDM) patients. A statistically significant increase in glucose and fructosamine was found in fasting NIDDM patients, as well as an increase in the oxidation induced by tert-butyl hydroperoxide. The Total Reactive Antioxidant Potential (TRAP) of the plasma was much reduced (p < .02) and the uricemia was unchanged. The erythrocytes of diabetic patients show greater basal oxidation products (p < .05), and the susceptibility of the diabetic erythrocytes to oxidation injury was also shown to increase in the oxidation induced by t-BOOH (p < .05). Linear regression studies showed that TRAP was associated directly with uric acid (p < .05) and inversely with fructosamine and with glucose (p < .03 and p < .05 respectively) in patients with NIDDM, but not in the controls. The levels of fructosamine were found to be related to the basal damage of the red blood cells (direct correlation, p < .001). This study suggest an useful approach to diabetic oxidative stress for clinical settings.

Errores metodológicos en resumenes de trabajos científicos / Metodological errores in scientifical abstracts

El perfil metodológico (PM) de resúmenes (RS) de investigación debería ajustarse a las exigencias del método científico, para asegurar su validez interna. Deben estar explicitados: población en estudio, objetivos, resultados y conclusiones y además, ser conexos y consistentes entre sí. Objetivos, Materiales y Métodos. Determinamos datos descriptivos genéricos y/o PM, de los RS publicados y presentados en Actas de los Congresos Internacionales de Medicina Interna del Hospital de Clínicas de los años 1992 y 1994. Se consideraron: número de RS por congreso, tipo de presentación (oral o escrita), instituciones de origen y número de los autores. Según el n muestral los RS se clasificaron en: Informe Científico (IC) (n=10), Caso único (n < 10), Sin registro (n no informado) y Sin casos (disertaciones). En los IC se analizó el PM: n muestral; tipo de problema; presencia, explicitación y conexidad de objetivos (Ob), resultados (Re) y conclusiones (Co). Se determinaron distribución de frecuencias y/o medidas de tendencia central. Resultados: se analizaron 310 RS: 157 del año 1992 y 153 del año 1994. De 310 trabajos, 81,9 por ciento se presentaron en forma oral y 73,87 por ciento correspondieron a autores de Instituciones Públicas. La media de autores por resumen fue de 5,17 ñ 2,08. Se presentaron: 52,58 por ciento IC; 32,9 por ciento Casos Unicos; 3,55 por ciento Sin Casos y 10,97 por ciento Sin Registro. En los 163 IC la mediana del n fue 67 (rango: 10-82637); 38,03 por ciento presentaban objetivos completos; 50,3 por ciento planteaban problemas de comparación y 44,2 por ciento problemas de cuantificación. Los diseños más frecuentes fueron: observacionales (74,20 por ciento), transversales (72,40 por ciento) y prospectivos (84 por ciento). El 72,4 por ciento informaban Re completos y el 77,9 por ciento Co. Se estableció conexidad en el 33,7 por ciento de los IC entre Re-Co, en el 21,5 por ciento entre Ob-Co, en el 29,40 por ciento entre Ob-Re y sólo en el 11,70 por ciento entre Ob-Re-Co. Conclusiones: 1.- La presentación más corriente fue la de IC, seguida por los Casos Unicos. . .

Errores metodológicos en resumenes de trabajos científicos / Metodological errores in scientifical abstracts

El perfil metodológico (PM) de resúmenes (RS) de investigación debería ajustarse a las exigencias del método científico, para asegurar su validez interna. Deben estar explicitados: población en estudio, objetivos, resultados y conclusiones y además, ser conexos y consistentes entre sí. Objetivos, Materiales y Métodos. Determinamos datos descriptivos genéricos y/o PM, de los RS publicados y presentados en Actas de los Congresos Internacionales de Medicina Interna del Hospital de Clínicas de los años 1992 y 1994. Se consideraron: número de RS por congreso, tipo de presentación (oral o escrita), instituciones de origen y número de los autores. Según el n muestral los RS se clasificaron en: Informe Científico (IC) (n=10), Caso único (n < 10), Sin registro (n no informado) y Sin casos (disertaciones). En los IC se analizó el PM: n muestral; tipo de problema; presencia, explicitación y conexidad de objetivos (Ob), resultados (Re) y conclusiones (Co). Se determinaron distribución de frecuencias y/o medidas de tendencia central. Resultados: se analizaron 310 RS: 157 del año 1992 y 153 del año 1994. De 310 trabajos, 81,9 por ciento se presentaron en forma oral y 73,87 por ciento correspondieron a autores de Instituciones Públicas. La media de autores por resumen fue de 5,17 ñ 2,08. Se presentaron: 52,58 por ciento IC; 32,9 por ciento Casos Unicos; 3,55 por ciento Sin Casos y 10,97 por ciento Sin Registro. En los 163 IC la mediana del n fue 67 (rango: 10-82637); 38,03 por ciento presentaban objetivos completos; 50,3 por ciento planteaban problemas de comparación y 44,2 por ciento problemas de cuantificación. Los diseños más frecuentes fueron: observacionales (74,20 por ciento), transversales (72,40 por ciento) y prospectivos (84 por ciento). El 72,4 por ciento informaban Re completos y el 77,9 por ciento Co. Se estableció conexidad en el 33,7 por ciento de los IC entre Re-Co, en el 21,5 por ciento entre Ob-Co, en el 29,40 por ciento entre Ob-Re y sólo en el 11,70 por ciento entre Ob-Re-Co. Conclusiones: 1.- La presentación más corriente fue la de IC, seguida por los Casos Unicos. . . (AU)

Vascular renin-like activity in aorta and mesenteric artery of the rat.

Vascular renin-like enzymatic activity (VRLA) has been measured in the artery wall of control and experimental rats. The following groups have been studied: 1-normal salt diet; 2-high salt diet; 3-low salt diet; 4-bilateral nephrectomy (Nx); 5-sham operated for Nx. VRLA was evaluated in the aorta (ARLA) and in the mesenteric arteries (MRLA). Blood samples were obtained for plasma renin activity (PRA) determination. High salt diet decreased PRA, ARLA and MRLA whereas low salt diet increased PRA, did not change ARLA and decreased MRLA. PRA was almost undetectable in Nx animals while ARLA showed a 40% reduction and MRLA was unchanged in these animals. These results would indicate that the changes in PRA induced different variations in the renin-like content of the aorta and the mesenteric artery. The differences could be mainly due to two factors: 1) the capacity of the vascular tissue to bind circulating renin and 2) the capacity of each tissue to synthetize renin-like material in situ.

Renin-like activity in vascular tissue of DOC-salt hypertensive rats.

The presence of isorenin active at the physiological pH was investigated in DOC-salt hypertensive rats. The effect of chronic captopril treatment was analyzed in similarly treated animals and in control rats. The levels of the plasma (PRA) and vascular enzyme (VRLA) were compared with those of untreated control animals. DOC-salt administration was maintained during 4 or 8 weeks. Captopril was given in the drinking fluid beginning 4 days before DOC-salt treatment. Renin-like activity was measured in the aorta and mesenteric arteries. DOC-salt treatment reduced PRA to almost undetectable levels while aorta renin-like enzyme only decreased to 50% at 4 weeks and was not changed at 8 weeks. Isorenin levels in the mesenteric artery did not show any significant variation. Captopril did not prevent the increase in blood pressure due to DOC-salt administration and it induced a significant increase in PRA and in VRLA in control rats whereas it did not increase either - enzyme in DOC-salt treated rats. In summary these results confirm the existence of a vascular isorenin and suggest that both binding and local synthesis of the enzyme could take place in the arterial wall.

Angiotensinogen concentration in the cerebrospinal fluid in different experimental conditions in the rat.

Angiotensinogen is the most important component of the renin-angiotensin system present in the cerebrospinal fluid (CSF) of the rat. Its physiological significance as well as its origin have not been clearly elucidated. In this experiment we have examined plasma renin activity (PRA) and plasma and CSF angiotensinogen concentration under the following experimental conditions in male rats of the Wistar strain: 1) adrenalectomy (Adx) 4 days prior to sample collection; controls were sham Adx animals; 2) nephrectomy (Nx) 48 hours before blood and CSF collection; controls were sham Nx rats; 3) DOC-salt treatment (Cortexon depot, 50 mg/kg.s.c. twice a week) plus saline to drink was given during 4 weeks; controls were intact rats; 4) DOC-salt plus captopril: captopril (100 mg/kg/day) in the drinking fluid was added to the treatment of experimental and control animals of Group 3; 5) two-kidney, two clip hypertension: silver clips placed in both renal arteries 8 weeks before samples collection; control: sham-operated rats; 6) water deprivation: rats deprived of water for 5 days; controls: intact rats; 7) peripheral sympathectomy: 6-hydroxydopamine (6-HODA) injected s.c. from birth until 16 weeks of age, adrenodemedullectomy and adrenal denervation performed at 8 weeks; controls were vehicle-injected animals. Determination of angiotensinogen concentration in plasma and CSF was accomplished by incubation of the samples with excess hog renin. The angiotensin I released as well as PRA were evaluated using an specific radioimmunoassay technique. PRA was significantly increased by Adx, captopril treatment, and water deprivation, and was almost suppressed by Nx, DOC-salt, and DOC-salt plus captopril treatment.(ABSTRACT TRUNCATED AT 250 WORDS)

Vascular structural changes in the artery wall of unilateral nephrectomized rats.

Wet and dry weight, concentration and total amount of nucleic acids and proteins, and incorporation of tritiated thymidine were measured in the arteries of rats after 7 and 15 days of unilateral nephrectomy, sham operation and in control animals. Arteries of uninephrectomized rats showed increased wet and dry weight, increased DNA and protein content after 7 and 15 days and a higher rate of tritiated thymidine uptake after the first week. These results suggest an early proliferative process in the arteries of unilateral nephrectomized rats.