Measurement of the peritoneal platelet activity through the effluent betathromboglobulin levels in CAPD patients.

Platelet activity is closely related to endothelium and could release factors able to influence capillary wall and surrounding tissues. BTG is a protein included in platelet vesicles and a measure of its activation. Some alterations of peritoneum could be partially related to platelet activity. BTG peritoneal transport from blood is weight limited (36000) and consequently, high levels in effluent should represent local production. The aim of this study has been to characterize peritoneal effluent BTG.12 patients, on CAPD 27 +/- 15 mon., 5 diabetics were studied. Previous peritonitis was 0.3 +/- 0.4 e/year. Determinations performed: Plasma (P) (BTG, T. protein, albumin, platelet count, Hcto and Fibrinogen) and Effluent (EF) (BTG, T. protein, Fibrinopeptide A, FDP, Fibrinolytic act., Fibrinogen, Plasminogen and Mitogenic induced capacity on Swiss 3T3 mice fibroblasts). To evaluate peritoneal function we used mass transfer coefficients (MTC) and net UF.R.:BTG levels: P 118 +/- 14 EF 34 +/- 14 ng/ml P/EF (%) 31 +/- 13 (6-54%). Regression analysis: P BTG did not show significant relationship with any of the studied parameters. EF BTG showed direct significant correlation (p less than 0.05) with Creatinine-MTC (r: 0.81) and EF Fibrinogen (0.68) and in the limit of significance with EF T. prot (0.57) and EF Mitogenicity (0.62). P/EF BTF showed significant correlation with creatinine-MTC (0.77). The analysis of these values grouping patients showed: diabetes has no influence on BTG values, hypertensive patients show higher P/EF BTG values than normotensive (39 +/- 9 vs 23 +/- 11%, p less than 0.05) and no influences of peritonitis or CAPD period were found.(ABSTRACT TRUNCATED AT 250 WORDS)

[Variable response to the biological inhibition of platelets by abciximab in patients subjected to percutaneous coronary angioplasty]. / Respuesta variable a la inhibición biológica de las plaquetas por abciximab en pacientes sometidos a revascularización coronaria percutánea.

INTRODUCTION AND OBJECTIVES: Abciximab has been shown to reduce the risk of thrombotic complications during coronary angioplasty, however there are still many aspects to be resolved. The aim of this study was to investigate the various biological effects of abciximab on platelets during coronary angioplasty. METHODS: The degree of platelet inhibition (with 5 and 20 mol/l concentrations of ADP), occlusion time (measurement of platelet haemostatic capacity, PFA-100), and the platelet activation markers were determined in 15 patients who underwent basal coronary angioplasty and abciximab treatment. Determinations were obtained before, 15 minutes after procedure initiation, at procedure termination, and 24 hours after procedure termination. RESULTS: More than 80% platelet aggregation inhibition was observed in 13 patients during the procedure, but after 24 hours (p < 0.05) was only detected in two. The occlusion time during the procedure was > 300 sec. in 13 patients, 6 of whom evolved to normal values after 24 hours (p < 0.05). A high correlation (p = 0.02) was found between these two parameters during the intervention, but not after 24 hours. No platelet inhibition or occlusion time changes were observed in 2 patients during the study. The expression of p-selectin increased significantly during the procedure (p < 0.05). CONCLUSIONS: The variability of platelet function inhibition and existence of circulating activation during coronary angioplasty following the administration of abciximab support the use of early analytical controls with the objective of modifying guidelines for use in order to optimize its effect or to combine it with other antithrombotic agents.

[Clinical and prognostic heterogeneity in Aicardi's syndrome: a description of two cases]. / Heterogeneidad clínica y pronóstica en el síndrome de Aicardi: a propósito de dos casos.

INTRODUCTION: Aicardi's syndrome is characterized by infantile spasms, agenesis of the corpus callosum and ocular lesions. Clinically it presents as severe mental retardation, severe limitation of motor development and of language, with a prognosis of survival for only a few months or years. We present two new cases of this uncommon syndrome and describe the heterogeneity of its clinical and prognostic severity. CLINICAL CASES: Case 1. A ten-month old patient had flexion spasms of the limbs at the age of 4 months, bilateral corioretinal lesions and generalized hypoplasia of the corpus callosum. During the clinical course of the disorder, the epileptic crises were controlled, there was mental retardation, the head was held steady and the baby could sit. Case 2. A nine year old patient had had flexion spasms when aged 2 months, had bilateral retinal lesions and generalized hypoplasia of the corpus callosum. During his clinical course the epileptic crises were controlled, there was severe mental retardation, the patient could pay attention and collaborate, articulate single words, walk on his own and manipulate objects. CONCLUSION: Aicardi's syndrome should be considered to be a syndrome in which the clinical findings and prognosis are heterogeneous, as seen from new cases with less clinical and functional limitation than the patients first described.

Molecular genetic analysis of a compound heterozygote for the glycoprotein (GP) IIb gene associated with Glanzmann's thrombasthenia: disruption of the 674-687 disulfide bridge in GPIIb prevents surface exposure of GPIIb-IIIa complexes.

This work was aimed at elucidating the molecular genetic lesion(s) responsible for the thrombasthenic phenotype of a patient whose low platelet content of glycoprotein (GP) IIb-IIIa indicated that it was a case of type II Glanzmann's thrombasthenia (GT). The parents did not admit consanguinity and showed a reduced platelet content of GPIIb-IIIa. Polymerase chain reaction (PCR)-single-stranded conformational polymorphism analysis of genomic DNA showed no mutations in the patient's GPIIIa and two novel mutations in the GPIIb gene: one of them was a heterozygous splice junction mutation, a C-->A transversion, at position +2 of the exon 5-intron 5 boundary [IVS5(+2)C-->A] inherited from the father. The predicted effect of this mutation, insertion of intron 5 (76 bp) into the GPIIb-mRNA, was confirmed by reverse transcription-PCR analysis of platelet mRNA. The almost complete absence of this mutated form of GPIIb-mRNA suggests that it is very unstable. Virtually all of the proband's GPIIb-mRNA was accounted for by the allele inherited from the mother showing a T2113-->C transition that changes Cys674-->Arg674 disrupting the 674-687 intramolecular disulfide bridge. The proband showed a platelet accumulation of proGPIIb and minute amounts of GPIIb and GPIIIa. Moreover, transfection and immunoprecipitation analysis demonstrated that [Arg674]GPIIb is capable of forming a heterodimer complex with GPIIIa, but the rate of subunit maturation and the surface exposure of GPIIb-IIIa are strongly reduced. Thus, the intramolecular 674-687 disulfide bridge in GPIIb is essential for the normal processing of GPIIb-IIIa complexes. The additive effect of these two GPIIb mutations provides the molecular basis for the thrombasthenic phenotype of the proband.