Response of asymptomatic cytomegalovirus viraemia to oral ganciclovir 3 g/day or 6 g/day in HIV-infected patients.

Reactivation of cytomegalovirus (CMV) following immunosuppression may result in the development of CMV disease and is associated with an increased risk of death. CMV viraemia detected by the polymerase chain reaction (PCR) precedes CMV disease in HIV-infected patients and identifies individuals at high risk of disease. Pre-emptive ganciclovir (GCV) therapy in patients who have evidence of CMV viraemia is effective in preventing disease. An open study was conducted to assess the response of CMV viraemia to oral GCV at a dose of 3 or 6 g/day for 28 days. HIV RNA was measured to determine if CMV inhibition affected HIV viral load. Fourteen patients were studied, three of whom entered both phases of the study. None of the patients had evidence of CMV disease at the time of entry into the trial; two patients developed CMV retinitis after completion of the trial. Oral GCV at both 3 and 6 g/day caused a decrease in CMV viral load in individual patients. However, a rebound in CMV viral load occurred in patients receiving the 3-g/day dose. None of the patients receiving oral GCV 3 g/day became PCR negative after 21 days compared with six of eight patients receiving 6 g/day. Five of eight patients (63%) receiving GCV 6 g/day were concurrently taking protease inhibitors compared with two of nine (22%) receiving 3 g/day. Ten patients remained PCR negative throughout follow up. No change was found in HIV viral load during receipt of GCV at either dose. Thus, oral GCV is effective in reducing CMV viral load, but a dose of 3 g/day is insufficiently potent for pre-emptive therapy.

Thrombin generation measured ex vivo following microvascular injury is increased in SLE patients with antiphospholipid-protein antibodies.

Antiphospholipid-protein antibodies (APA) include lupus-type anticoagulant (LA) and antibodies recognizing complexes of anionic phospholipids (e.g. cardiolipin) and proteins (e.g. prothrombin and beta2-glycoprotein I). The presence of APA is associated with an increased risk of both arterial and venous thrombosis. However, the pathogenic mechanism leading to thrombosis in patients with APA remains unclear. We studied 32 patients with systemic lupus erythematosus (SLE) who were divided into two groups depending on the presence (n = 19) or absence (n = 13) of APA. Healthy volunteers (n = 12) matched by age and sex served as controls. In all subjects LA and IgG class anticardiolipin antibodies (ACA) were determined. Thrombin generation was monitored ex vivo measuring fibrinopeptide A (FPA) and prothrombin fragment F1 + 2 (F1 + 2) in blood emerging from a skin microvasculature injury, collected at 30 second intervals. In subjects with antiphospholipid antibodies mean FPA and F1 + 2 concentrations were significantly higher at most blood sampling times than in controls. In some SLE patients with APA the process of thrombin generation was clearly disturbed and very high concentrations of fibrinopeptide A were detected already in the first samples collected. Two minutes after skin incision SLE patients without APA produced slightly more FPA, but not F1 + 2, as compared to healthy subjects. Mathematical model applied to analyze the thrombin generation kinetics revealed that APA patients generated significantly greater amounts of thrombin than healthy controls (p = 0.02 for either marker). In contrast, in the same patients generation of thrombin in recalcified plasma in vitro was delayed pointing to the role of endothelium in the phenomenon studied. In summary, these data show for the first time that in SLE patients with antiphospholipid-protein antibodies thrombin generation after small blood vessel injury is markedly increased. Enhanced thrombin generation might explain thrombotic tendency observed in these patients.

Thrombin generation markers and coronary heart disease risk factors in a Polish population sample.

Thrombosis plays a major role in the development of atherosclerosis and its acute vascular complications. Epidemiological studies have shown that elevated levels of plasma fibrinogen are associated with an increased risk of coronary heart disease (CHD). It is not clear whether this association is linked to hemostatic functions of fibrinogen which serves as a substrate for thrombin. Generation of thrombin in vivo can be evaluated by measurement of its specific markers in plasma, i.e. thrombin-antithrombin III complex (TAT) and prothrombin fragment 1 + 2 (F1 + 2). We determined plasma levels of TAT and F1 + 2 in a population sample of southeastern Poland and evaluated relations of these markers with plasma fibrinogen, factor VII coagulant activity (FVIIc), and other known CHD risk factors. The population studied consisted of 215 men and 251 women, aged 43-75 years. Final analysis was performed on 195 men and 222 women. The distribution of plasma TAT and F1 + 2 concentrations were highly skewed with the higher median values for women than for men. Log values of TAT correlated with log values of F1 + 2 in men (r = 0.27, p < 0.01) and in women (r = 0.15, p < 0.05). In the regression analysis both markers were positively related to age in women but not in men. After adjustment to age there was a positive relation between TAT and fibrinogen in both sexes. In women, but not in men, F1 + 2 showed a positive association with FVIIc. Total plasma cholesterol was negatively related to TAT in women only. There was no association between thrombin generation markers and plasma triglycerides, HDL-cholesterol, LDL-cholesterol, blood pressure, cigarette smoking and body mass index (BMI). The association of plasma fibrinogen and FVIIc with thrombin generation markers points to an important role of the hemostatic system in the pathogenesis of atherosclerosis and coronary heart disease in humans.

[Prevalence of thrombosis in secondary antiphospholipid-protein syndrome]. / Powiklania zakrzepowo-zatorowe we wtórnym zespole przeciwfosfolipidowo-bialkowym.

Antiphospholipid-protein syndrome (APS) comprises venous and arterial thrombosis, spontaneous abortion and thrombocytopenia in patients with antiphospholipid-protein antibodies (APA). Such antibodies are detected by immunoenzymatic (ELISA) methods (e.g. anticardiolipin antibodies-ACL) or coagulation assays (lupus anticoagulant-LA). APS in patients showing other symptoms of autoimmune disease is called secondary antiphospholipid-protein syndrome. The aim of the study was to find relation between history of thrombosis and APA in a group of patients with lupus erythematosus and lupus-like disease. Lupus anticoagulant was detected by a three step procedure using phospholipid dependent clotting assays and anticardiolipin antibodies were measured by ELISA. We studied 95 subjects (91 women, 4 men) suffering from lupus erythematosus (67 patients) and lupus-like-disease (28 patients). Lupus anticoagulant was found in 26, anticardiolipin antibodies IgG in 34 and IgM in 27 subjects. In a retrospective study 40 thrombotic events were detected in 36 patients; deep vein thrombosis in 19, pulmonary embolism in 7, ischaemic CNS events in 13 and myocardial infarction in one. Thrombosis was present more often in subjects with LA (61%) and ACL IgG (52%) than in subjects without these antibodies (24%) (p = 0.004 and 0.015, respectively). ACL IgM antibodies were not related to thrombotic episodes. The ACL IgG antibodies and LA are helpful in identifying subjects at risk factors of venous and arterial thrombosis among patients suffering from lupus erythematosus and lupus-like disease.

[High levels of cholesterol and lipoprotein (A) in serum decreases the inhibitory effect of aspirin on generation of thrombin]. / Wysokipoziom cholesterolu i lipoproteiny (A) w surowicy zmniejsza hamujacy wplyw aspiryny na generacje trombiny.

Aspirin (ASA) is widely used in the treatment of cardiovascular diseases. Recently, we have found that aspirin decreases not only platelet aggregation but also thrombin generation. This effect, however, was seen only in certain subjects. Therefore we decided to examine influence of a single dose of aspirin (500 mg) on thrombin generation in healthy volunteers. Thrombin genesis was assessed by serial measurements of fibrinopeptide A concentration in blood emerging from standardised forearm skin incisions. Aspirin reduced thrombin generation in persons with normal serum level of lipids. This effect was lost, however, in subjects with high level of cholesterol and lipoprotein (a)--well known risk factors of ischaemic heart disease. While the mechanism by which aspirin affects thrombin generation remains to be elucidated, our data indicate that hypercholesterolemic subjects might benefit less than others from preventive aspirin treatment.

Epstein-Barr virus-carrying B cells are large, surface IgM, IgD-bearing cells in normal individuals and acute malaria patients.

In this study the presence of Epstein-Barr virus (EBV) carrying B lymphocytes in different B-cell subpopulations from peripheral blood was determined by spontaneous outgrowth which gives rise to lymphoblastoid cell lines. In healthy seropositive adults, the EBV-carrying B cell was predominantly within the IgM- and IgD-positive but not the IgG-positive subpopulations. Furthermore, these B lymphocytes were in the low-density (large cell) Percoll fraction. The IgM- and IgD-positive B cell phenotype suggests the EBV-carrying B cells to be circulating virgin B cells recently released from the bone marrow. These B cells have an estimated life span of only 6-8 weeks suggesting that long-term EBV persistence in the body may be the result of infection of a more primitive B-cell type. Similar experiments were carried out in children with acute malaria from the Gambia, West Africa, where Burkitt lymphoma (BL) is endemic in order to determine whether a population of EBV-carrying B cells could be identified which had a similar phenotype to the BL cell. The EBV-carrying B cells in this patient group were also found in the IgM-positive, IgG-negative B-cell subpopulation. The majority of these cells were found in the low-density (large cell) Percoll fraction although in some patients a proportion was derived from the high-density (small cell) fraction. This cellular phenotype is not representative of a BL cell.

Integumentomuscular sac of Ascaris lumbricoides suis L: a biomembrane for studies on the transport of chemical substances.

The whole integumentomuscular sac of the worm Ascaris lumbricoides suis L. and pouches isolated from it seemed to be a good model for investigation of the transmembrane transport of chemical substances across tissue barriers.

Further studies on the properties of bile acids. I. Bile acid-induced changes of the action of drugs acting on the autonomic nervous system on the heart and blood vessels.

The action of certain drugs on the autonomic system was studied under the influence of bile acids: 3,12-dihydroxycholanic acid (deoxycholic), 3,7,12-trihydroxycholanic acid (cholic), and 3,7,12-triketocholanic acid (dehydrocholic). The experiments were carried out on rat heart in vivo and on isolated rat vessel preparation. It was shown that bile acids reduced the stimulating effect of isoprenaline on rat heart and the relaxing effect on the blood vessels. An inversion of the effects of adrenaline and noradrenaline on the rat heart was observed, and an enhancement of the vasoconstrictor effect of these substances. Under the conditions of this experiment an inversion was noted of the action of acetylcholine on the heart and blood vessels.

Serum lipoproteins, lipid peroxides and prostacyclin biosynthesis in patients with coronary heart disease.

Serum low-density lipoproteins (LDL) and high-density lipoproteins (HDL) were prepared by gradient ultracentrifugation and dialysis from 12 healthy subjects and 15 patients with coronary heart disease and hyperlipoproteinemia. In both lipoprotein fractions cholesterol and lipid peroxides were determined. The effect of these lipoproteins on spontaneous prostacyclin biosynthesis in rat aortic slices was studied. Serum lipoproteins were susceptible to peroxidation during the preparation procedure. LDL were more prone to peroxidation than HDL. Little lipid peroxides were formed in lipoproteins when calcium ions had been removed by EDTA, and when butylated hydroxytoluene (BHT) was present at all stages of their preparation. LDL when prepared without these precautions either from healthy subjects or from patients with coronary heart disease markedly suppressed prostacyclin generation by rat aortic slices. This inhibition was unrelated to LDL-cholesterol, but was due to LDL-lipid peroxides. Peroxide-low LDL prepared from most of the healthy subjects and patients with coronary heart disease and concomitant hyperlipoproteinemia, did not inhibit prostacyclin biosynthesis. However, in one quarter of the patients, LDL was inhibitory. Consequently, in some patients with coronary heart disease, there operate unknown mechanisms which are responsible for the inhibitory activity of LDL on prostacyclin generation.

Investigations of anthelminthic activity and synthesis of new derivatives of perhydroazepine, perhydro-1,4-diazepine, perhydro-1,4-oxazepine and perhydro-1,5-oxazocine.

Anthelminthic activity of new esters of 3,4,5-trimethoxybenzoic acid containing rests of the title heterocyclic amines has been determined. 3-(Perhydroazepinyl)-propyl ester 6 acts on enchytraeids in vitro 56-fold stronger than piperazine adipate, 2-(perhydroazepinyl)-ethyl ester 5 is the most effective in a therapy of mice infested with nematodes.

Application of the isotope technique in pharmacodynamic analysis of penetration of drugs into parasites.

Penetration of piperazine adipate into Ascaris lumbricoides var. suum L. was studied by scintigraphy andautoradiography. The results indicate that anthelminthic drugs, including piperazine, penetrate into the parasite mainly through the mouth or other natural orifices, and only slightly through the cuticle, and that the amount of piperazine that penetrates depende on its concentration in the solution.