Introduction: liver disease resulting from chronic hepatitis C virus (HCV) infection follows an asymptomatic course towards cirrhosis and its complications in 20-40% of cases. Earlier studies demonstrated that advanced fibrosis is a prognostic factor. The "gold standard" for the evaluation of fibrosis grade is liver biopsy. Our group validated a predictive index - NIHCED - based on demographic, laboratory parameters, and echoghraphic data to determine the presence of cirrhosis. Objective: our objective is to evaluate whether the NIHCED score predicts the presence of advanced fibrosis in patients with chronic HCV infection. Material and methods: this prospective study included patients with chronic HCV infection who underwent liver biopsy and were administered the NIHCED score. Fibrosis grade correlated with the NIHCED score using the ROC curve analysis and Spearman's correlation coefficient. Results: in total 321 patients were included (male/female ratio 1.27) with a mean age of 48 ± 14 years. Liver biopsy showed that 131 (30.5%) had no fibrosis or had portal expansion while 190 (69.5%) had advanced fibrosis or cirrhosis. At a cut-off point of 6, sensitivity was 72%, specificity was 76.3%, positive predictive value (PPV) was 81%, negative predictive value (NPV) was 63.7%, and diagnostic accuracy was 72.5%, with an area under the curve (AUC) of 0.787, and a Spearman's correlation coefficient of r = 0.65. Conclusions: the NIHCED score predicts the presence of advanced fibrosis in an elevated percentage of patients with a need of liver biopsy.

Introducción: la hepatitis crónica por VHC cursa de forma asintomática desarrollando cirrosis hepática y sus complicaciones en un 20-40% de los casos. En estudios previos se ha demostrado que la fibrosis avanzada es un factor pronóstico fundamental. El método gold standard para la valoración del grado de fibrosis es la biopsia hepática. Nuestro grupo ha validado un índice predictivo, el NIHCED (Sabadell's Non Invasive, Hepatitis C related-Cirrosis Early Detection Score), basado en datos demográficos, analíticos y ecográficos para determinar la presencia de cirrosis. Objetivo: nuestro objetivo es el de evaluar si el NIHCED predice la presencia de fibrosis avanzada en los pacientes con hepatitis crónica por virus C. Material y métodos: estudio prospectivo donde se incluyeron pacientes con hepatitis crónica por VHC. Se les realizó una biopsia hepática y el NIHCED. El grado de fibrosis se correlacionó con el valor del NIHCED mediante curva de ROC y el coeficiente de correlación de Spearman. Resultados: se incluyeron un total de 321 pacientes (ratio hombre/mujer 1,27) con una edad media de 48 ± 14 años. La biopsia hepática mostró que 131 (30,5%) no tenían fibrosis o era expansión portal, mientras que 190 (69,5%) tenían fibrosis avanzada o cirrosis. Para un punto de corte de 6 puntos, la sensibilidad fue del 72%, especificidad del 76,3%, VPP del 81%, VPN del 63,7% y una precisión diagnóstica del 72,5%, con un área bajo la curva fue de 0,787 y un coeficiente de correlación de Spearman de r = 0,65. Conclusiones: el NIHCED predice la presencia de fibrosis avanzada en un elevado porcentaje de pacientes sin necesidad de realizar biopsia hepática.

Background: hepatocellular carcinoma (HCC) is a cancer with high incidence and mortality. Objective: our aim was to describe the natural history of a patient cohort with HCC, and to identify the factors associated with survival. Patients and methods: a retrospective and descriptive study of patients diagnosed with HCC between 1995 and 2002. Qualitative variables were expressed as frequencies and percentages. Quantitative variables were expressed as medians and standard deviations. Survival was calculated using the Kaplan-Meier method and log rank. Results: a total of 154 patients were analyzed. The men-to-women ratio was 2.9/1. Mean age was 68 ± 9 years. 82% of patients died during a median follow-up of 28 months. Median survival was 21.5 months (95% CI: 16.98-26.04). Curative treatment was done in 40.3% of diagnosed patients, and 59.7% of patients received palliative treatment. Factors associated with survival were: ascites, number of lesions at diagnosis, and curative treatment. No statistical differences were found for the next factors: age, sex, etiology of cirrhosis, and Child-Pugh stage at diagnosis. Conclusions: factors associated with low survival in patients with HCC were ascites and number of lesions. Curative treatment is associated with a higher survival when compared to palliative treatment.

Introducción: el carcinoma hepatocelular (CHC) es una neoplasia con una elevada incidencia y una alta mortalidad. Objetivo: nuestro objetivo es la descripción de la historia natural de una cohorte de pacientes con CHC e identificar variables asociadas a supervivencia. Material y métodos: estudio retrospectivo y descriptivo de pacientes diagnosticados de CHC entre 1995-2002. Las variables cualitativas se expresaron mediante frecuencias y porcentajes y las cuantitativas con mediana y desviación típica. La supervivencia se estimó mediante el método de Kaplan Meyer y la prueba de Log Rank. Resultados: se analizaron un total de 154 pacientes con CHC. La ratio hombre-mujer fue de 2,9/1. La edad media de 68 ± 9 años. El 82% de los pacientes fueron exitus en un tiempo medio de seguimiento de 28 meses. La mediana de supervivencia fue de 21,5 meses (IC 95%: 16,98-26,04). Se realizó tratamiento con intención curativa en un 40,3% y el resto tratamiento paliativo. Las variables asociadas a la supervivencia fueron: presencia o no de ascitis, el número de lesiones en el momento del diagnóstico y si el tratamiento realizado fue con intención curativa o no. No hubieron diferencias estadísticamente significativas respecto a: sexo, edad, etiología de la cirrosis y estadio de Child en el momento del diagnóstico. Conclusiones: los factores asociados a una menor supervivencia en los pacientes con carcinoma hepatocelular fueron la presencia de ascitis y el número de lesiones en el momento del diagnóstico. La realización de tratamiento con intención curativa se asocia a una mayor supervivencia.

A model based on kinetic, thermodynamic and physicochemical concepts, is presented and an integrodifferential approach to find the fundamental events, is used for microemulsion polymerization (MEP). The procedure was applied to experimental conversion data of hexyl methacrylate (C6MA) and styrene (STY) in MEP. It was found that: (i) nucleation rate is not linear with time, opposed to previous reports, (ii) coagulation rate is negligible, (iii) micelles provide monomer to reacting particles, (iv) a vitreous effect, even in polymers with a Tg lower than the reaction temperature, was found, (v) radical entry to particles is negligible confirming previous reports, (vi) the decreasing reaction rate interval, besides monomer depletion, is caused by a decrease in active reaction sites, and (vii) a three-parameter phenomenological model is presented capable of describing the studied systems.

En este trabajo se propone un modelo basado en conceptos cinéticos, termodinámicos y fisicoquímicos y se utiliza un enfoque integrodiferencial (ID) para encontrar los mecanismos fundamentales de la polimerización en microemulsión (PME). El procedimiento ID se aplica a datos experimentales de conversión del metacrilato de hexilo (C6MA) y del estireno (STY) en la PME. Este procedimiento permitió encontrar que: (i) la rapidez de nucleación no es lineal con el tiempo, contrario a lo reportado con anterioridad, (ii) la coagulación entre partículas es despreciable, (iii) las micelas aportan monómero a las partículas reaccionantes, (iv) el efecto vítreo es importante, aun en polímeros con Tg menor a la temperatura de reacción, (v) la entrada de radicales a las partículas es despreciable, confirmando propuestas anteriores, (vi) el intervalo de rapidez decreciente de reacción, además de la disminución de monómero, se debe a la disminución de sitios activos, y (vii) un modelo fenomenológico de tres parámetros es capaz de describir todos los sistemas estudiados.

Objective: Paratesticular tumors are very rare and mostly bening. Wa aport a new case of adenomatoid tumor of epididymis. Method: Male of 40 years old with solid lesion in epidididymis tale treated with mass exéresis. Results: Adenoamotid tumor of the epididymis confirmed with hystopathologic technique. Conclusion: Adenomatoid tumor of epididymis is the most frequent paratesticular tumors and when is suspected, conservative surgery must be performed.

Objetivo: Los tumores paratesticulares son poco habituales siendo en la mayoría de los casos benignos. Aportamos un nuevo caso de tumor adenomatoide de epidídimo. Método: Varón de 40 años con masa sólida en cola epidídimo tratada mediante exéresis de la misma. Resultados: Tumor adenomatoide confirmado mediante inmunohistoquímica. Conclusión: El tumor adenomatoide es el más frecuente de los tumores paratesticulares y su sospecha permite realizar cirugía conservadora.

The interaction of plasminogen, tissue plasminogen activator (t-PA) and urokinase with a clinical strain of Helicobacter pylori was studied. Plasminogen bound to the surface of H. pylori cells in a concentration-dependent manner and could be activated to the enzymatic form, plasmin, by t-PA. Affinity chromatography assays revealed a plasminogen-binding protein of 58.9 kDa in water extracts of surface proteins. Surface-associated plasmin activity, detected with the chromogenic substrate CBS 00.65, was observed only when plasminogen and an exogenous activator were added to the cell suspension. The two physiologic plasminogen activators, t-PA and urokinase, were also shown to bind to and remain active on the surface of bacterial cells. epsilon-Aminocaproic acid caused partial inhibition of t-PA binding, suggesting that the kringle 2 structure of this activator is involved in the interaction with surface receptors. The activation of plasminogen by t-PA, but not urokinase, strongly depended on the presence of cells and a 25-fold enhancer effect on the initial velocity of activation by t-PA compared to urokinase was established. Furthermore, a relationship between cell concentration and the initial velocity of activation was demonstrated. These findings support the concept that plasminogen activation by t-PA on the bacterial surface is a surface-dependent reaction which offers catalytic advantages.

The effect of several ions (Cl-, Na+, K+, Ca2+) on the rate of plasminogen (Pg) activation by recombinant staphylokinase (rSTA) is reported. Both monovalent and divalent ions affect the rate at which Pg is activated by rSTA, in a concentration-dependent manner (range 0-100 mM). In almost all cases, a decrease of the initial velocity of activation was observed. Cl- showed the most striking inhibitory effect at low concentrations (64% at 10 mM). However, in the presence of a fibrin surface, this inhibition was attenuated to 38%. Surprisingly, 10 mM Ca2+ enhanced the Pg activation rate 21% when a polymerized fibrin matrix was present. These data support the idea that ions can modulate the rate of Pg activation through a mechanism that may be associated with changes in the molecular conformation of the zymogen. This effect is strongly dependent on the presence of a fibrin clot.

We cloned the streptokinase (STK) gene of Streptococcus equisimilis in an expression vector of Escherichia coli to overexpress the profibrinolytic protein under the control of a tac promoter. Almost all the recombinant STK was exported to the periplasmic space and recovered after gentle lysozyme digestion of induced cells. The periplasmic fraction was chromatographed on DEAE Sepharose followed by chromatography on phenyl-agarose. Active proteins eluted between 4.5 and 0% ammonium sulfate, when a linear gradient was applied. Three major STK derivatives of 47.5 kDa, 45 kDa and 32 kDa were detected by Western blot analysis with a polyclonal antibody. The 32-kDa protein formed a complex with human plasminogen but did not exhibit Glu-plasminogen activator activity, as revealed by a zymographic assay, whereas the 45-kDa protein showed a Km = 0.70 µM and kcat = 0.82 s-1, when assayed with a chromogen-coupled substrate. These results suggest that these proteins are putative fragments of STK, possibly derived from partial degradation during the export pathway or the purification steps. The 47.5-kDa band corresponded to the native STK, as revealed by peptide sequencing