The HSP90 inhibitor, XL888, enhanced cell apoptosis via downregulating STAT3 after insufficient radiofrequency ablation in hepatocellular carcinoma

AIMS

Radiofrequency ablation (RFA) is the first-line option for early-stage hepatocellular carcinoma (HCC). However, the residual tumor attributed to insufficient RFA (iRFA) led to tumor recurrence and metastasis. Novel combination strategies are urgently needed to enhance efficiency of RFA.

MAIN METHODS

For in vitro iRFA models, HCC cells were placed in a water bath at 46 °C for 10 min and then returned to the original incubator. For in vivo models, HCC cells were implanted subcutaneously into nude mice. The nude mice were then randomly assigned into 4 groups: control group, XL888 group, iRFA group, combination of XL888 and iRFA group. CCK8 was performed to detect cell viability; Hoechst 33258 was used to explore nuclear morphology; The expression levels of proteins were demonstrated by western blotting; Co-localization of HSP90 and STAT3 was elucidated by immunofluorescence confocal microscopy; Immunohistochemistry was used to explore expression levels of proteins at tissue level.

KEY FINDINGS

XL888 promoted apoptosis of HCC cells induced by heat via inhibiting expression levels of Mcl-1 and cleaved-caspase 3 in vivo and in vitro. XL888 attenuated the complex formation of HSP90 and STAT3, leading to decreased expression levels of STAT3 and p-STAT3. In human HCC tissues, IHC scores of HSP90 were positively correlated with those of STAT3. Overexpression of STAT3 rescued cell apoptosis induced by co-treatment of XL888 and heat.

SIGNIFICANCE

We implied that XL888 promoted apoptosis of HCC cells induced by heat via disrupting the binding of HSP90 and STAT3, providing theoretical basis for a novel combination strategy for HCC.

Di-(2-Ethylhexyl) Phthalate Increases Obesity-Induced Damage to the Male Reproductive System in Mice

OBJECTIVE

This study evaluated the effects of di-(2-ethylhexyl) phthalate (DEHP) and obesity on male reproductive organ function in male mice and the potential mechanism of male secondary hypogonadism (SH) in such mice.

METHODS

140 mice were assigned to six groups for 12 weeks: normal, DEHP, DIO, DIO + DEHP low, DIO + DEHP middle, and DIO + DEHP high. The effects of DEHP and obesity upon the reproductive organs were determined by measuring sperm count and motility, relative testis and epididymis weight, hormone level, and pathological changes. Oxidative stress was evaluated by determining malondialdehyde, T-AOC, SOD, GSH, H2O2, CAT, and GSH-PX in testicular tissues. Nrf2 and Keap1 protein were measured by Western blotting.

RESULTS

DEHP and obesity reduced sperm count and motility, relative testis and epididymis weight, and testosterone level but increased the levels of MDA, H2O2, leptin, and estradiol. Pathological injury was observed in the testicular Leydig cells. Moreover, the activity of CAT, SOD, and GSH-Px enzymes was inhibited. Nrf2 protein expression was reduced but that of Keap1 was increased.

CONCLUSIONS

DEHP and obesity jointly caused damage to male productive function. Oxidative stress in testicular tissue, and a high level of leptin, may provide some evidence to clarify the mechanisms of male SH with DEHP and obesity.

Efficacy of N,N'bis-(2-mercaptoethyl) isophthalamide on mercury intoxication: a randomized controlled trial

BACKGROUND

Chronic mercury intoxication is a severe health issue and occurs especially in gold mining communities. Common chelators used for improving mercury elimination are not everywhere available and challenged by poor cell wall penetration. This study is part of a feasibility trial and the aim was to gather first information about the efficacy of the newly developed chelator N,N'bis-(2-mercaptoethyl) isophthalamide (NBMI) on chronic mercury intoxication.

METHODS

In this three-armed, placebo-controlled randomized trial, 36 miners with mercury urine levels exceeding 15 μg/l were administered 100 mg NBMI, 300 mg NBMI or placebo for 14 days. Levels of mercury in urine [μg/l and μg/g creatinine] and plasma l were analyzed. Therapeutic effect was assessed using the medical intoxication score (MIS) and its single health outcomes (e.g. excessive salivation, sleeping problems), fatigue scores, a neuromotoric test battery (CATSYS) and a neurological outcome (Finger to nose test).

RESULTS

Physical fatigue was significantly decreased in the 300 mg NBMI group compared to the control. Mercury concentration in urine following 300 mg NBMI treatment was significantly lowered compared to control, however, this effect was less distinct with adjustment for creatinine.

CONCLUSION

NBMI showed an effect on physical fatigue and there were indications to positive effects on other symptoms as well. More comprehensive studies are mandatory to verify the effects of NBMI as a novel tool for treating mercury intoxications.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02486289 . Date of registration: June 24, 2015.

Nanocrystal-Polymer Particles: Extended Delivery Carriers for Osteoarthritis Treatment

An efficient treatment for osteoarthritis (OA) can benefit from the local release of a high therapeutic dose over an extended period of time. Such a treatment will minimize systemic side effects and avoid the inconvenience of frequent injections. To this aim, nanocrystal-polymer particles (NPPs) are developed by combining the advantages of nanotechnology and microparticles. Nanocrystals are produced by wet milling kartogenin (KGN), which is known to promote chondrogenesis and to foster chondroprotection. A fluorescent biodegradable polymer is synthesized for intravital particle tracking. Polymer microparticles with 320 nm embedded KGN nanocrystals (KGN-NPPs) show a high drug loading of 31.5% (w/w) and an extended drug release of 62% over 3 months. In vitro, these particles do not alter mitochondrial activity in cultured human OA synoviocytes. In vivo, KGN-NPPs demonstrate higher bioactivity than a KGN solution in a murine mechanistic OA model based on histological assessment (Osteoarthritis Research Society International score), epiphyseal thickness (microcomputed tomography), OA biomarkers (e.g., vascular endothelial growth factor, Adamts5), and prolonged intra-articular persistence (fluorescence analysis). This work provides proof-of-concept of a novel and innovative extended drug delivery system with the potential to treat human OA.

A new CysLT1 and CysLT2 receptors-mediated anaphylaxis guinea pig model

Although the effectiveness of CysLT₁ receptor antagonists on asthma has been clinically established, the effects of CysLT₂ receptor antagonists are still unclear. The purpose of this study was to develop a new CysLT₁ and CysLT₂ receptors-mediated anaphylaxis guinea pig model using S-hexyl GSH, a γ-glutamyl transpeptidase (GTP) inhibitor, to suppress conversion of LTC₄ to LTD₄. Actively sensitized guinea pigs were challenged with OVA in the absence or presence of S-hexyl GSH, and survival rate following anaphylactic response was monitored. OVA-induced fatal anaphylaxis in the absence of S-hexyl GSH was almost completely inhibited by montelukast, a CysLT₁ receptor antagonist, but not by the CysLT₂ receptor antagonist BayCysLT₂RA. However, under treatment with S-hexyl-GSH, the inhibitory effect of motelukast was dramatically diminished, whereas that of BayCysLT₂RA was markedly increased. The dual CysLT_1/2 receptor antagonist ONO-6950 effectively inhibited anaphylactic response in both S-hexyl GSH-treated and non-treated animals. LC/MS/MS analysis revealed that S-hexyl GSH treatment actually inhibited LTC₄ metabolism in the blood and lung tissues. Using S-hexyl GSH, we developed a novel CysLT₁ and CysLT₂ receptors-mediated anaphylaxis guinea pig model that can be useful for not only screening both CysLT₂ and CysLT_1/2 receptors antagonists, but also for functional analysis of CysLT₂ receptors.

Barbatic Acid Offers a New Possibility for Control of Biomphalaria Glabrata and Schistosomiasis

This study evaluated the biological activity of an ether extract and barbatic acid (BAR) from Cladia aggregata on embryos and adult mollusks of Biomphalaria glabrata, cercariae of Schistosoma mansoni and the microcrustacean Artemia salina. The ether extract and BAR were obtained by successive extractions with diethyl ether. The obtained extracts were analyzed using thin-layer chromatography (TLC), high-performance liquid chromatography (HPLC), proton nuclear magnetic resonance (¹H-NMR) and infrared (IR) spectroscopy. The results demonstrated that the ether extract exerted embryotoxic effects at 50 and 100 µg/mL and molluscicidal effects at 20 and 25 µg/mL. BAR exhibited no embryotoxicity, and its molluscicidal concentration was equal to that of the ether extract. However, after 60 min of exposure, 1 µg/mL BAR presented cercaricidal activity against the parasite S. mansoni at the second larval stage. Neither substance induced toxicity against A. salina. These results indicate the potential molluscicidal activities of the ether extract and BAR against B. glabrata and S. mansoni cercariae. In addition to these effects, there was a lack of toxicity against the aquatic environment and no damage to the biota, indicating the potential of these products for large-scale control and/or eradication of schistosomiasis.

Retinoic acid and TGF-β signalling cooperate to overcome MYCN-induced retinoid resistance

BACKGROUND

Retinoid therapy is widely employed in clinical oncology to differentiate malignant cells into their more benign counterparts. However, certain high-risk cohorts, such as patients with MYCN-amplified neuroblastoma, are innately resistant to retinoid therapy. Therefore, we employed a precision medicine approach to globally profile the retinoid signalling response and to determine how an excess of cellular MYCN antagonises these signalling events to prevent differentiation and confer resistance.

METHODS

We applied RNA sequencing (RNA-seq) and interaction proteomics coupled with network-based systems level analysis to identify targetable vulnerabilities of MYCN-mediated retinoid resistance. We altered MYCN expression levels in a MYCN-inducible neuroblastoma cell line to facilitate or block retinoic acid (RA)-mediated neuronal differentiation. The relevance of differentially expressed genes and transcriptional regulators for neuroblastoma outcome were then confirmed using existing patient microarray datasets.

RESULTS

We determined the signalling networks through which RA mediates neuroblastoma differentiation and the inhibitory perturbations to these networks upon MYCN overexpression. We revealed opposing regulation of RA and MYCN on a number of differentiation-relevant genes, including LMO4, CYP26A1, ASCL1, RET, FZD7 and DKK1. Furthermore, we revealed a broad network of transcriptional regulators involved in regulating retinoid responsiveness, such as Neurotrophin, PI3K, Wnt and MAPK, and epigenetic signalling. Of these regulators, we functionally confirmed that MYCN-driven inhibition of transforming growth factor beta (TGF-β) signalling is a vulnerable node of the MYCN network and that multiple levels of cross-talk exist between MYCN and TGF-β. Co-targeting of the retinoic acid and TGF-β pathways, through RA and kartogenin (KGN; a TGF-β signalling activating small molecule) combination treatment, induced the loss of viability of MYCN-amplified retinoid-resistant neuroblastoma cells.

CONCLUSIONS

Our approach provides a powerful precision oncology tool for identifying the driving signalling networks for malignancies not primarily driven by somatic mutations, such as paediatric cancers. By applying global omics approaches to the signalling networks regulating neuroblastoma differentiation and stemness, we have determined the pathways involved in the MYCN-mediated retinoid resistance, with TGF-β signalling being a key regulator. These findings revealed a number of combination treatments likely to improve clinical response to retinoid therapy, including co-treatment with retinoids and KGN, which may prove valuable in the treatment of high-risk MYCN-amplified neuroblastoma.

Masterclass series in peripheral arterial disease

Peripheral arterial disease (PAD) of the lower extremities is a common and potentially life-threatening manifestation of systemic atherosclerosis. Significant PAD is identified by an ankle brachial index (ABI) <0.90; its presence is strongly associated with the major modifiable cardiac risk factors. Early detection and treatment of asymptomatic PAD is a current focus of numerous cardiovascular guideline organizations as less than a third of patients report typical claudication symptoms. This has created an ever-increasing treatment gap, whereby millions of eligible patients are inadequately treated. Risk factor management including exercise, smoking cessation, and aggressive treatment of lipids and blood pressure are essential in PAD patients. However, life-long antiplatelet therapy provides additional reductions in vascular events beyond aggressive risk factor management. The use of aspirin as well as more potent antiplatelet therapies such as thienopyridines holds promise for reducing atherothrombosis in this very high-risk population.

Kartogenin-Incorporated Thermogel Supports Stem Cells for Significant Cartilage Regeneration

Recently, cartilage tissue engineering (CTE) attracts increasing attention in cartilage defect repair. In this work, kartogenin (KGN), an emerging chondroinductive nonprotein small molecule, was incorporated into a thermogel of poly(L-lactide-co-glycolide)-poly(ethylene glycol)-poly(L-lactide-co-glycolide) (PLGA-PEG-PLGA) to fabricate an appropriate microenvironment of bone marrow mesenchymal stem cells (BMSCs) for effective cartilage regeneration. More integrative and smoother repaired articular surface, more abundant characteristic glycosaminoglycans (GAGs) and collagen II (COL II), and less degeneration of normal cartilage were obtained in the KGN and BMSCs coloaded thermogel group in vivo. In conclusion, the KGN-loaded PLGA-PEG-PLGA thermogel can be utilized as an alternative support for BMSCs to regenerate damaged cartilage in vivo.

A review of picotamide in the reduction of cardiovascular events in diabetic patients

Picotamide is an antiplatelet drug with a dual inhibitory action. Thus, picotamide inhibits both thromboxane A2 (TxA2) receptors and TxA2 synthase and, at variance with aspirin, does not interfere with endothelial prostacyclin (PGI2) production. Two large randomized trials have been performed to assess the clinical efficacy of picotamide in patients at risk of atherothrombosis. The ADEP study compared peripheral artery disease (PAD) patients randomized to picotamide or placebo. This study did not show a significant reduction of cardiovascular events by picotamide but a subgroup analysis showed its potential usefulness in patients with diabetes. To investigate this issue further, the DAVID study recently enrolled diabetic patients with PAD randomized to picotamide versus aspirin; the results showed a significant reduction of overall mortality in the picotamide group. Moreover long-term picotamide treatment in diabetes promotes the reduction of microalbuminuria and the inhibition of growth of carotid plaques. These data suggest that picotamide may represent an interesting drug to be further investigated in future trials in the atherothrombotic setting.

Treatment of aura: solving the puzzle

Migraine with aura (MwA) sufferers, at times, need specific treatments. This is the case when the auras are frequent, prolonged and cause anxiety and distress. Abnormal release of glutamate, which may trigger auras, and abnormal platelet behaviour, which constitutes a possible predisposing factor to MwA, are possible targets for MwA-specific prophylactic therapy. Here we present results obtained using lamotrigine (two open trials), an agent known to inhibit glutamate release, and picotamide, an antiplatelet drug, in the prophylactic treatment of MwA sufferers. Lamotrigine significantly reduced the frequency of MwA attacks, and picotamide together with lamotrigine reduced the duration and/or the occurrence of auras. In comparison to lamotrigine, the therapy with picotamide may have some advantages such as the use of the therapeutic dose from the first day of treatment (lamotrigine needs one month or more to reach such a dose) and the possibility to prevent cerebral ischaemic events and migraine stroke, a rare but severe complication of MwA attacks.

Picotamide in migraine aura prevention: a pilot study

In an open, preliminary trial we evaluated the use of picotamide, an antiplatelet drug, in the prophylactic treatment of migraine aura (MA). Twenty-two women suffering from migraine with typical aura or MA without headache, diagnosed according to International Headache Society criteria, entered a nine-month study. They underwent a three-month run-in period free of prophylactic drugs, followed by a six-month treatment period (subdivided in two trimesters, TI and TII) with 300 mg of picotamide administered twice daily. A detailed diary reporting neurological symptoms, duration and frequency of MA was compiled by patients along the trial time. The number of MA significantly decreased during treatment (from 6.85+/-3.82 in the run-in trimester to 2.85+/-2.72 during TI and to 2.55+/-2.89 during TII). Also, MA duration was decreased significantly, being 36.75+/-20.28 min during run-in, 20.00+/-16.94 during TI and 17.75+/-16.26 during TII. In 25% of patients MA totally disappeared. The number and the features of aura neurological symptoms were also positively modified by the use of picotamide. No serious adverse event was provoked by picotamide administration. Picotamide is effective in reducing MA frequency, duration and symptomatology. The effect is clearly evident in the first trimester of treatment and is maintained with no further modifications during the second trimester.

[Efficacy of galavit in patients with duodenal ulcer]

The aim of the study was to investigate clinical efficacy of the medical complex Galavit in patients with acute phase of duodenal ulcer (DU) in. The subjects were 60 DU patients aged 32 +/- 2 years with ulcerous defects of 0.4 to 1.3 cm in diameter. In patients receiving Galavit, pain was coped with by Mann-Whitney method in 2.5 +/- 0.2 days, p < 0.001; in the control group--in 5.7 +/- 0.1 days. In the Galavit group the ulcers healed in 11.3 +/- 0.2 days, p < 0.001; in the control group--17.8 +/- 0.3 days; in 4 cases (13.3%) the ulcerous defects healed with forming of rough scars. Galavit elevated T-lymphocyte rate from 53.1 +/- 0.6% to 65.1 +/- 0.2%, p < 0.001; T-helper inductor level--from 27.8 +/- 0.2% to 38.5 +/- 0.3%, p < 0.001; cytotoxic T-lymphocyte level--from 18.5 +/- 0.5% to 27.3 +/- 0.3%, p < 0.001; B-lymphocyte level--from 12.3 +/- 0.2% to 19.1 +/- 0.1%, p < 0.001. The therapy significantly lowered malonic aldehyde level by 23.5%, trienoic conjugate level--by 61.6%; superoxide dismutase level rose 1.6 times, catalase level--1.4 times, glutathion reductase level--from 19.03 +/- 1.17 to 27.01 +/- 1.24 optical density units/mg, p < 0.001. The study did not find any significant changes in the immune status and lipid peroxidative/antioxidative system of patients receiving basic therapy. The results show that Galavit has anti-inflammatory effect, improves immune status and anti-oxidative protection. It is appropriate to administer Galavit as a component of DU basic therapy. The results show that Galavit has anti-inflammatory effect, improves immune status and anti-oxidative protection. It is appropriate to administer Galavit as a component of DU basic therapy.

Picotamide, a combined inhibitor of thromboxane A2 synthase and receptor, reduces 2-year mortality in diabetics with peripheral arterial disease: the DAVID study

AIMS

Patients with diabetes are at excessive risk of mortality and cardiovascular morbidity. Previous studies suggest that aspirin may be less effective in diabetic patients. In this multi-centre, randomized, double blind trial picotamide, a dual inhibitor of thromboxane A2 synthase and receptor, was compared with aspirin for the prevention of mortality and major cardiovascular events in diabetics with peripheral arterial disease (PAD).

METHODS AND RESULTS

A total of 1209 adults aged 40-75 years with type 2 diabetes and PAD were randomized to receive picotamide (600 mg bid) or aspirin (320 mg od) for 24 months. The cumulative incidence of the 2 years overall mortality was significantly lower amongst patients who received picotamide (3.0%) than in those who received aspirin (5.5%) with a relative risk ratio for picotamide versus aspirin of 0.55 (95% CI: 0.31-0.98%). Events were reported in 43 patients (7.1%) on picotamide and 53 (8.7%) on aspirin. The combined endpoint of mortality and morbidity had a slightly lower incidence in the picotamide group but this difference did not reach statistical significance.

CONCLUSION

Picotamide is significantly more effective than aspirin in reducing overall mortality in type 2 diabetic patients with associated PAD.

Lack of modifying effects of 4-tert-octylphenol and benzyl butyl phthalate on 3, 2'-dimethyl-4-aminobiphenyl-induced prostate carcinogenesis in rats

The modifying effects of dietary feeding of two estrogenic compounds, 4-tert-octylphenol (tOP) and benzyl butyl phthalate (BBP), on 3,2-dimethyl-4-aminobiphenol (DMAB)-induced prostatic carcinogenesis were investigated in male F344 rats. We also assessed the effects of the test compounds on the proliferating cell nuclear antigen (PCNA) index in induced neoplasms, prostatic intra-epithelial neoplasm (PIN), and non-lesional glands in the prostate. To induce prostatic neoplasms, rats were given subcutaneous injections of DMAB (25 mg/kg body weight) every other week, 10 times in total. They also received the experimental diet containing 10 or 100 ppm tOP and BBP for 40 weeks, starting 1 week after the last dosing of DMAB. DMAB exposure produced prostatic adenocarcinoma with an incidence of 41.2% at the end of the study (week 60). Dietary administration of tOP and BBP did not affect the incidence of prostatic adenocarcinoma: 43.8% in the DMAB --> 10 ppm tOP group; 25.0% in the DMAB --> 100 ppm tOP group; 43.8% in the DMAB --> 10 ppm BBP group; and 43.8% in the DMAB --> 100 ppm BBP group. The PCNA indices in adenocarcinomas, PIN, and non-lesional glands in rats treated with DMAB and tOP or BBP were slightly lower than that of the DMAB alone group, but the differences were not statistically significant. These results might suggest that dietary feeding of the estrogenic compounds tOP and BBP did not modulate DMAB-induced prostatic carcinogenesis in rats.

Assessing human exposure to phthalates using monoesters and their oxidized metabolites as biomarkers

Phthalates are a group of industrial chemicals with many commercial uses, such as solvents, additives, and plasticizers. For example, di-(2-ethylhexyl) phthalate (DEHP) is added in varying amounts to certain plastics, such as polyvinyl chloride, to increase their flexibility. In humans, phthalates are metabolized to their respective monoesters, conjugated, and eliminated. However, despite the high production and use of DEHP, we have recently found that the urinary levels of the DEHP metabolite mono-(2-ethylhexyl) phthalate (MEHP) in 2,541 persons in the United States were lower than we anticipated, especially when compared with urinary metabolite levels of other commonly used phthalates. This finding raised questions about the sensitivity of this biomarker for assessing DEHP exposure. We explored the utility of two other DEHP metabolites, mono-(2-ethyl-5-oxohexyl) phthalate (MEOHP) and mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), as additional DEHP biomarkers. These metabolites are formed by oxidative metabolism of MEHP. In urine from 62 people, both the range and the mean urinary levels of MEOHP and MEHHP were on average 4-fold higher than those of MEHP; the mean of the individual ratios of MEHHP/MEOHP, MEHHP/MEHP, and MEOHP/MEHP were 1.4, 8.2, and 5.9, respectively. These data suggest that MEOHP and MEHHP are more sensitive biomarkers of exposure to DEHP than is MEHP. These findings also suggest a predominant human metabolic route for DEHP hydrolysis to MEHP followed by oxidation of MEHP; they also imply that a similar mechanism may be relevant for other high-molecular-weight phthalates, such as di-n-octyl, di-isononyl, and di-isodecyl phthalates.

The effects of mouth rinses and dentifrice-containing magnesium monoperoxyphthalate (mmpp) on oral microflora, plaque reduction, and mucosa

The effects of a magnesium monoperoxyphthalate (MMPP) mouth-rinse, with or without sodium lauryl sulphate (SLS), and an MMPP dentifrice, on salivary counts of bacterial flora and yeasts, and on supragingival plaque scores were investigated in 131 healthy oral candida carriers over a 9 week double blind study. There were no changes in the salivary counts of bacteria studied (anaerobes, streptococci, fusobacteria, Actinomyces, Viellonella) in the test or placebo groups. A significant increase in salivary candida counts was seen in subjects using an MMPP rinse and dentifrice compared with placebo subjects and this phenomenon was not influenced by the presence of SLS. A significant reduction in plaque was seen in subjects using an MMPP rinse and dentifrice compared with placebo subjects. Frank candidosis was observed in only 2 subjects (1 in the placebo rinse group and 1 in the MMPP dentifrice group) but erythematous lesions, with subjective reports of soreness, dryness or burning sensation, were recorded and observed more frequently in the experimental groups than in the placebos, especially in those also using SLS. The substantial plaque reduction achieved with MMPP in the absence of tooth staining but with the increase in salivary Candida counts suggests that further studies of MMPP are warranted.

Determinants of fibrinogen in an Italian population suffering from claudication. Lower fibrinogen in the south compared to middle and north of Italy. The ADEP Group

BACKGROUND AND OBJECTIVE

Prospective studies have shown that high plasma levels of fibrinogen are independently associated with the risk of cardiovascular complications. In patients suffering from peripheral vascular disease (PVD) fibrinogen has been shown to be an independent predictor of cardiovascular disease but its determinants have never been examined in this clinical setting.

DESIGN AND METHODS

Fibrinogen levels were related to clinical and laboratory variables in 2,111 patients suffering from PVD. We also analyzed whether there was a regional distribution of risk factors.

RESULTS

The median values of fibrinogen was 312 mg/dL. The clinical variables examined did not differentiate patients with elevated or normal fibrinogen levels. In particular, patients with ankle/arm pressure ratio < 0.8 did not show a higher prevalence of fibrinogen > 312 mg/dL. Conversely, white blood cell (WBC) count and serum cholesterol levels were significantly associated with high fibrinogen levels (p < 0.0001). Multiple logistic regression analysis demonstrated that areas of Italy were differently associated with high plasma fibrinogen levels (p < 0.03): subjects in the north and middle of Italy having significantly higher values of fibrinogen than subjects in the south of Italy (p < 0.01). A similar regional distribution was observed for WBC count and serum cholesterol levels.

INTERPRETATION AND CONCLUSIONS

The regional distribution of risk factors raises the question as to whether the already reported large variability of cardiovascular events so in PVD may be attributed to a non homogeneous distribution of risk factors.

Long-term treatment with the dual antithromboxane agent picotamide decreases microalbuminuria in normotensive type 2 diabetic patients

Picotamide both inhibits thromboxane synthetase and acts as a thromboxane antagonist at the receptor level. We investigated the long-term effect of picotamide on urinary albumin excretion (UAE) at rest and induced by exercise in 30 type 2 diabetic patients who were normotensive and had microalbuminuria while at rest. The subjects of our study had a mean age of 52.5 +/- 1.6 years, BMI of 28.5 +/- 0.7 kg/m2, diabetes duration of 9.1 +/- 1.8 years, and HbA1c of 7.0 +/- 0.8%. The study was a randomized double-blind placebo-controlled trial. The patients were randomly allocated to receive for 1 year either picotamide, 300 mg, 3 tablets/day, or placebo, 3 tablets/day. The patients were asked to visit our outpatient clinic after 1, 3, 6, 9, and 12 months of treatment. At all times, blood pressure, microalbuminuria at rest, blood glucose, serum creatinine, serum picotamide, and creatinine clearance were measured; at baseline and after 6 and 12 months, all patients underwent submaximal physical exercise. After 6 months of picotamide, baseline and exercise-induced microalbuminuria were significantly decreased (up to one-third) as compared with the baseline and placebo level, with no further drops at month 12 of picotamide treatment. On placebo treatment, UAE at rest and after exercise was slightly increased compared with baseline values. The effects of picotamide occurred without significant side effects or changes in either blood pressure levels or glycometabolic control. Our study is the first long-term intervention trial in type 2 diabetes showing that an antithromboxane agent is able to decrease microalbuminuria, which in this disease is a dual marker of macro- and microangiopathy. Our findings suggest an important role for thromboxane in the pathophysiology of microalbuminuria in diabetes; moreover, we hypothesize that antithromboxane agents may have a place in the treatment/prevention of both macro- and microvascular complications in type 2 diabetic patients.

The effects of thromboxane A2 inhibition (picotamide) and angiotensin II receptor blockade (losartan) in primary Raynaud's phenomenon

OBJECTIVES

To assess the role of thromboxane A2 and of angiotensin II in patients with primary Raynaud's phenomenon.

DESIGN

After an eight-day run-in period, the patients were enrolled in a single-blind, cross-over, study.

SETTING

Patients were examined at the Ambulatory for Microcirculatory Diseases of the Clinic of Internal Medicine, University Hospital, Verona.

SUBJECTS

Fifteen subjects affected by primary Raynaud's phenomenon were included.

MAIN OUTCOME MEASURES

A piezoelectric plethysmography to evaluate the distensibility of the digital arteries as the ratio between peak time (PT) and total time (TT), and an oscillometric blood pressure recorder were used after the run-in period, and after a two-week course of picotamide (300 mg b.i.d., i.e. two times daily) or losartan (12.5 mg once daily) with an interval of a week of placebo between the active treatments. The tests were performed after every treatment in basal condition and during mental stress. The patients reported in a diary the number and the severity (from 0 to 4 +) of the vasospastic crises.

RESULTS

The change in TP/TT ratio appeared statistically significant only after losartan treatment, both in basal condition and during mathematical stress. Both pharmacological treatments, with respect to placebo, showed an improvement of the scores, derived from the number and severity of vasospastic attacks, but only the therapy with losartan determined a statistically significant improvement.

CONCLUSIONS

The inhibition of the type 1 receptor for angiotensin II seems highly effective in the reduction of the vasospastic crises in the subjects with primary Raynaud's phenomenon. According to our experience, losartan could be used more extensively in the treatment of these patients besides arterial hypertension.

Antiaggregatory effects of picotamide in long-term treatment: a 2-year, double-blind placebo-controlled trial

The ex vivo antiaggregatory activity of picotamide, a dual antithromboxane agent, was assessed to find whether it was maintained in long-term treatment. In a double-blind, placebo-controlled 2-year study, 50 type 2 diabetic patients (35 men and 15 women; mean age 66 +/- 5 years) were enrolled and randomly given picotamide, 300 mg t.i.d. or the corresponding placebo. Platelet aggregation studies were performed at baseline and after 1, 3, 6, 12, 18 and 24 months. Compliance to the treatment was assessed by pill count at each visit. Forty-nine patients concluded the study. Starting from month 1, compared with placebo, picotamide-treated patients showed a significant inhibition of agonist-induced (ADP, arachidonic acid and collagen) platelet aggregation (-41%). The antiaggregatory effect was maintained throughout the study. At month 24, in the picotamide group, platelet aggregation was significantly lower compared with placebo (-30%). After 24 months of treatment, 20 out of 23 (86%) picotamide-treated patients showed a significant inhibition of platelet aggregation, whereas the remaining three patients had a normal platelet response. During the study, 12 patients suffered from thrombotic events of death: nine in the placebo group and three in the picotamide group, respectively. It was concluded that picotamide maintains its antiaggregatory effect, in long-term treatment, in more than 85% of patients.

Reduced chlorhexidine tooth stain coverage by sequential administration of monoperoxyphthalic acid in the beagle dog

Extrinsic tooth stain is sometimes a side-effect observed with the chronic use of chlorhexidine-containing oral care products. This chlorhexidine (CHX)-induced tooth staining is observed both in humans as well as in experimental animals. The present study tested the hypothesis that the sequential administration of monoperoxyphthalic acid (MPA) will reduce the development of chlorhexidine-induced tooth stain coverage in a beagle dog. For this study, dogs were treated with 30 mL of mouthrinse b.i.d. for 28 days. The following treatment groups ( = 12 dogs/group) were tested: water (negative control), 1.0% MPA rinse, 0.12% CHX rinse, and 1.0% MPA rinse followed by 0.12% CHX rinse. The sequential dosing of 1.0% MPA followed by 0.12+ CHX resulted in significantly (p < or = 0.05) less tooth stain than when dogs were dosed with 0.12% CHX alone. Additionally, the sequential dosing of MPA followed by chlorhexidine resulted in a 75% reduction in plaque formation in this model, which was significantly different (p < or = 0.05) from results with either treatment alone. A further study demonstrated that similar results could be obtained when MPA plus CHX treatment alone. A further study demonstrated that similar results could be obtained when MPA plus CHX treatments were separated by approximately a five-hour period in an AM and PM schedule. We conclude that the oxidizer, MPA, can significantly reduce tooth stain induced by CHX while enhancing its antiplaque and antigingivitis activity.

Effects of picotamide, an antiplatelet agent, on cardiovascular, events in 438 claudicant patients with diabetes: a retrospective analysis of the ADEP study

Picotamide is an antiplatelet drug which inhibits thromboxane A2 (TxA2) synthase and antagonizes TxA2 receptors. In the ADEP (Atherosclerotic Disease Evolution by Picotamide) trial, 2304 patients with peripheral obstructive arterial disease (POAD) were studied in a double-blind, placebo-controlled, 18-month, multicentre trial. In this study, 151 events (13.1%) occurred on placebo and 122 (10.6%) on picotamide (900 mg day-1). The relative risk reduction was 19%, (P = 0.056). This paper reports a post-hoc analysis in a subgroup of 438 diabetic patients (picotamide = 230; placebo = 208). There were 32 vascular events on placebo (15%) and 18 on picotamide (8%) (relative risk reduction: 48%; 95% CI = 26, 76; P = 0.022). The results of this retrospective analysis suggest that a prospective study to investigate events in claudicant patients with diabetes mellitus is warranted.

Safety and efficacy of picotamide, a dual anti-thromboxane agent, in patients with thrombocytosis and a previous thromboembolic event: a 1-year observational study

Patients with chronic myeloproliferative disease are at increased risk of both thromboembolic and haemorrhagic complications. Cerebral thrombosis is a common cause of death in myeloproliferative disease patients. Picotamide is a new anti-platelet drug sharing a dual anti-thromboxane activity: inhibition of thromboxane A2 synthase and thromboxane A2 receptor antagonism. Picotamide inhibits in vitro and ex vivo platelet aggregation induced by different agonists. Interestingly, in vitro studies show that picotamide is able to increase prostacycline biosynthesis. In the clinical setting, picotamide treatment induces only a slight prolongation of bleeding time. The safety and efficacy of picotamide long-term treatment in 15 patients with essential thrombocytosis and a positive history of previous thromboembolic events was evaluated. After 12-month treatment with picotamide no patients suffered from thrombotic events and only one minor and transient bleeding episode was observed. This observational long-term trial shows that picotamide treatment in patients with thrombocytosis at high risk of thrombotic events is safe and well tolerated. Picotamide did not increase the risk of bleeding in these patients, while at the same time, no thrombotic events were observed during the 1-year treatment.

Relation between risk factors and cardiovascular complications in patients with peripheral vascular disease. Results from the A.D.E.P. study

The relationship between risk factors and the onset of cardiovascular events was analyzed in patients suffering from peripheral obstructive arterial disease. One thousand and eleven patients were recruited in 120 Italian centers and participated in a clinical trial on picotamide (A.D.E.P. study), whose results have been previously reported. Patients were followed-up for 18 months and cardiovascular events were recorded. Hypertension (35%), smoking (34%), and diabetes (19%) were the most common risk factors at baseline. During the follow-up period, 246 patients (11.7%) had a cardiovascular event, mainly affecting cerebral, cardiac or peripheral circulation. Thirty-five of these events (14.2%) were fatal. A logistic regression analysis showed in general that hypertension (odds ratio 1.48), an ankle arm pressure ratio lower than 0.8 (odds ratio 1.42), smoking (odds ratio 1.43), previous vascular surgery (odds ratio 1.35), high white blood cell (WBC) count (odds ratio 1.15 for a difference of 2.0 x 10(9) WBC/1) and plasma fibrinogen (odds ratio 1.16 for a difference of 1.05 g/l) were significantly associated with a higher incidence of cardiovascular events. In particular, deaths of any origin were more frequent in patients with an ankle/arm pressure ratio below 0.8. High plasma fibrinogen increased the risk of cerebrovascular events, hypertension or coronary heart events and, to a less evident extent, peripheral vascular complications and cerebrovascular events. A history of vascular surgery increased the risk of peripheral vascular complications. Both smoking and a high WBC count showed to be borderline significant risk factors for coronary heart events and the former also for peripheral vascular complications. In male patients (84%), ankle/arm pressure ratio lower than 0.8, high fibrinogen and hypertension were the most important factors for cardiovascular events. This study helps to identify some categories at higher risk of cardiovascular events among patients with peripheral obstructive arterial disease; this finding is useful to plan future trials to decrease the frequency of such complications.

Thrombotic and hemorrhagic complications in chronic myeloproliferative disorders

Bleeding and thrombosis are major causes of morbidity and mortality in patients with chronic myeloproliferative disorders. We retrospectively evaluated 101 consecutive patients affected by primary thrombocytosis (46 male, 55 female, aged 18-84 years; mean +/- SD 61 +/- 15) followed for a period ranging from 6 months up to 10 years (median 5 years) at our hematological unit. At the time of diagnosis 48 patients were asymptomatic; 26 had clinical evidence of atherothrombosis (cerebral ischemic attacks, ischemic heart disease, peripheral occlusive arterial disease), ten had venous thrombosis, four experienced major hemorrhages, 23 presented microvascular ischemic manifestations namely erythromelalgia, paresthesias, acrocyanosis and dizziness. At presentation 51.2% of the patients had elevated serum lactic dehydrogenase, 34.5% hyperuricemia, and 23.4% serum creatinine > 1.2 mg/dL. Color Doppler ultrasound provided evidence of vascular stenosis or medium-intimal hyperplasia of epiaortic vessels in 48.9% of patients studied, and similar alterations of lower limb arteries in 23.8% of cases. Therapy modality included an antiplatelet agent (picotamide 300 mg/bid); a cytoreductive agent (busulphan, hydroxyurea, pipobroman or melphalan) was used when platelet count was > 800000/microL. Symptoms due to microvascular ischemia promptly regressed after picotamide and cytoreductive therapy. During follow-up. nine patients suffered from atherothrombotic events (transient ischemic attacks, ischemic stroke, unstable angina pectoris) and five developed deep vein thrombosis or superficial thrombophlebitis. Five patients experienced major hemorrhages (two melena, two hematuria, one perioperative bleeding); the two gastrointestinal hemorrhages occurred in patients self-medicated with non steroidal anti-inflammatory drugs, and the two episodes of hematuria occurred on oral anticoagulant therapy and aspirin respectively. No major bleeding occurred in patients on continuative therapy with picotamide, even in the presence of upper digestive tract disorders. Seven patients died: mortality resulted from one sudden coronary death, three solid neoplasia, one blast crisis, one anile, and one massive hemorrhage due to abdominal aortic prosthesis tearing. Our study suggests that a long-term antithrombotic prophylaxis with picotamide may be of benefit in patients affected by primary thrombocytosis; a controlled clinical trial is warranted to assess whether picotamide can ameliorate the natural history of the disease.

Heparin-induced thrombocytopenia with arterial thrombosis: an unusual case

A case of heparin-induced thrombocytopenia with thrombosis (HITT) is described. The patient, treated for several days with porcine Ca-heparin at a dosage of 10,000 IU/day, presented severe thrombocytopenia (Plt 36 x 10(9)/L), intermittent right leg ischemia, and a positive heparin-induced platelet aggregation assay. We promptly discontinued heparin and started picotamide, an antiplatelet drug. Rapid clinical improvement was observed in a few days. We stress the unusual features of the reported case (HITT during prophylactic therapy with low doses of porcine heparin; intermittent thrombosis), and we suggest picotamide represents a rational therapy for HITT on the basis of clinical and pathogenetic considerations.

Effects of picotamide, an antithromboxane agent, on carotid atherosclerotic evolution. A two-year, double-blind, placebo-controlled study in diabetic patients

BACKGROUND AND PURPOSE

We assessed the effects of long-term treatment with picotamide, an antiplatelet agent with dual antithromboxane activity, on the evolution of early asymptomatic carotid atherosclerotic lesions in diabetic patients.

METHODS

In a double-blind, placebo-controlled, 2-year study, 50 type II normotensive diabetic patients (35 men; mean age, 66 +/- 5 years) with asymptomatic mild or moderate nonstenotic (< 50%) carotid atherosclerotic lesions and negative history of cerebrovascular ischemic events were enrolled and randomly given picotamide (300 mg TID) or the corresponding placebo. A high-resolution, real-time B-scan echographic assessment of carotid arteries was performed at baseline and after 1, 3, 6, 12, 18, and 24 months of double-blind treatment. Prevalence and evolutionary trends of carotid atherosclerotic lesions (number per patient and mean stenosis expressed as percent) were considered as efficacy primary end points.

RESULTS

At baseline, mean +/- SD numbers of carotid atherosclerotic lesions per patient were 2.7 +/- 1.8 and 2.2 +/- 1.2 in the picotamide and placebo groups, respectively. Mean +/- SD percent stenosis was 25.3 +/- 7% in the picotamide group and 27.3 +/- 6% in the placebo group. Forty-nine patients completed the study. At month 24, the placebo group (n = 24) showed a significant progression in number of carotid atherosclerotic lesions (3.04 +/- 1.8; P < .02 versus baseline) and in mean percent stenosis (35 +/- 17%; 95% confidence interval, 33% to 37%; P < .01 versus baseline). In the picotamide group (n = 25), mean number of carotid atherosclerotic lesions (2.7 +/- 1.6) and percent stenosis (26 +/- 9%; 95% confidence interval, 24.8% to 27.2%) remained unchanged. At month 24, compared with randomized placebo, lesion numbers (P < .03) and percent stenosis (P < .01) in the picotamide group were significantly lower. During the study, 12 patients experienced major or minor ischemic vascular events (9 in the placebo group and 3 in the picotamide group; P = .07).

CONCLUSIONS

In diabetic patients compared with patients receiving placebo, long-term treatment with picotamide can slow the evolution of early carotid atherosclerotic lesions, inhibiting progression of plaque number and growth.

Effect of picotamide and aspirin, combined or alone, on platelet aggregation in patients with cerebral infarction

After 7 and 90 days of treatment, we studied the effect of picotamide, a thromboxane synthase inhibitor (450 and 900 mg/day), aspirin (150 mg/day), and aspirin plus picotamide (150 and 450 mg/day respectively) on platelet aggregation, evaluated in platelet rich plasma of 48 patients affected by ischemic stroke. Platelet aggregation, induced by collagen (1.0 and 2.0 micrograms/ml) and adenosine diphosphate (1.0 and 10 micrograms/L), was significantly increased in patients in comparison with healthy controls. Aspirin (150 mg/day) reduced collagen-induced platelet aggregation (1.0 microgram/ml) after 7 days of treatment. Picotamide (450 mg/day) reduced platelet aggregation induced by both concentrations of collagen, while the higher dose (900 mg/day) had no significant effect. Aspirin plus picotamide reduced the aggregation induced by 1.0 microgram/ml collagen and by 10 mumol/L adenosine diphosphate after 90 days of therapy. This study has shown that patients during the acute phase of stroke are characterized by an increased in vitro platelet aggregation. Aspirin may be beneficial in the acute phase of the cerebral ischemic event. Picotamide and picotamide plus aspirin could be useful for reducing platelet aggregation in long term treatment.

[Massive endocardial thrombosis in a patient with a peritoneo-jugular shunt for refractory ascites: the therapeutic success of tissue plasminogen activator and defibrotide]

The authors report a case of a patient with a refractory ascites due to extrahepatic portal thrombosis in course of idiopathic thrombocythemia. A peritoneovenous shunt was applied and as a late complication a massive thrombosis of the intracardiac portion of the duct developed. Thrombolysis was obtained with tissue plasminogen activator at doses usually administered for acute myocardial infarction. Prophylaxis of recurrence was pursued with pictomide and defibrotide.

Effect of long-term administration of picotamide on baseline and exercise-induced urinary albumin excretion in patients with type II diabetes mellitus and incipient nephropathy

The present pilot study investigated the effect of long-term treatment with picotamide on baseline and exercise-induced urinary albumin excretion levels in normotensive patients with type II diabetes mellitus. Six patients with type II diabetes were studied: four patients (two men and two women; mean age, 52 +/- 11 years) were treated for 9 months with picotamide (300 mg, TID) and two patients who did not receive the study medication served as controls. Three of the picotamide-treated patients were given a cycloergometric exercise test at baseline and after 3 and 6 months of therapy to evaluate the effects of the drug on exercise-induced microalbuminuria. Microalbuminuria at rest was measured in all patients at baseline and after 3, 6, and 9 months. At the end of the study, all the picotamide-treated patients demonstrated a significant decrease in microalbuminuria at rest (from 41.7 +/- 12.7 micrograms/min at baseline to 11.8 +/- 3 micrograms/min after 9 months) and after exercise (peak at baseline 103 +/- 36 micrograms/min vs 65.8 +/- 11 micrograms/min after 6 months). Conversely, in the two controls, microalbuminuria at rest increased from 45.1 +/- 0.9 micrograms/min at baseline to 151 +/- 59 micrograms/min at the end of the 9-month study period. (All values given as mean +/- SEM.) In conclusion, long-term administration of picotamide was effective in reducing abnormal exercise-induced microalbuminuria and albuminuria at rest. These findings suggest that long-term treatment with picotamide of normotensive patients with type II diabetes mellitus and incipient nephropathy may slow the progression of the nephropathy in its early stages.

Hemodynamic, hemorheologic, and hemocoagulative changes after treatment with picotamide in patients affected by peripheral arterial disease (PAD) of the lower limbs

Effects of picotamide on platelet activity and on some hemorheologic, coagulative, and hemodynamic parameters were investigated in a randomized, double-blind, placebo-controlled study for eighteen months. Twenty patients, average age 61.5 +/- 9.6 (SD) years, with peripheral arterial disease (PAD) at functional stage 2 of the Fontaine classification and with intermittent claudication for at least six months were studied. Ten patients received tablets of picotamide, 300 mg three times a day, and 10 subjects received three identical placebo tablets each day. Similar atherosclerotic disease risk factors were present in both groups. Picotamide induced a significant decrease of plasma viscosity, fibrinogen, and beta-thromboglobulin and an increase of amplitude of the photoplethysmographic wave.

The role of extraplatelet thromboxane A2 in unstable angina investigated with a dual thromboxane A2 inhibitor: importance of activated monocytes

BACKGROUND

The role of thromboxane A2 (TxA2) in unstable angina has not yet been defined. TxA2 receptor antagonists may be of value in studying this role.

METHODS

To investigate whether TxA2 has a pathogenetic effect on the occurrence of myocardial ischemia and from what source TxA2 originates, we studied TxA2 formation by unstimulated monocytes from patients with unstable angina (n = 40), stable effort angina (n = 20), and controls (n = 20). We also compared the effects of picotamide (1200 mg/day), a TxA2-synthase inhibitor and TxA2-receptor antagonist, with those of aspirin (325 mg/day) on myocardial ischemia and TxA2 formation by monocytes and platelets. The double-blind randomized study was performed on patients with unstable angina on continuous Holter monitoring.

RESULTS

In the presence of autologous lymphocytes, unstimulated monocytes from patients with unstable angina formed significantly (P < 0.001) more TxA2 than those from controls or from patients with effort angina. Although TxA2 formation by circulating monocytes and platelets was inhibited to a greater degree by aspirin than by picotamide (88 +/- 6 and 98 +/- 2%, respectively, versus 65 +/- 2 and 74 +/- 1%, P < 0.001), aspirin failed to affect the occurrence of myocardial ischemia whereas picotamide significantly (P < 0.001) reduced the number of anginal attacks (84.8%), silent ischemic episodes (64.2%), and overall duration of ischemia (69.8%), in comparison to the run-in period.

CONCLUSIONS

These results indicate that TxA2 formed by monocytes contributes to the pathogenesis of myocardial ischemia in unstable angina. TxA2 formation occurs mainly in extravascular spaces, probably within the coronary vascular wall. Picotamide appears to control myocardial ischemia effectively in patients with unstable angina.

Effect of picotamide on the clinical progression of peripheral vascular disease. A double-blind placebo-controlled study. The ADEP Group

BACKGROUND

Patients with peripheral vascular disease (PVD) undergo a clinical course that can be complicated by cardiovascular events occurring in several areas of the circulation.

METHODS AND RESULTS

In the present study we investigated the ability of picotamide, a substance that inhibits platelet thromboxane A2 (TxA2) synthase and antagonizes TxA2 receptors, to reduce cardiovascular complications in PVD patients. The study was double blind and placebo controlled. After a 1-month run-in period, 2,304 patients were randomly allocated to either placebo or picotamide (300 mg t.i.d.) and followed for 18 months. Major and minor events were analyzed. Results of an "intention-to-treat analysis" were that patients on picotamide suffered 45 major events (3.9%) and 77 minor events (6.7%), whereas those taking placebo suffered 52 major (4.5%) and 99 minor events (8.6%). There was borderline statistical difference between the two groups with respect to the sum of the major and minor events (risk reduction, 18.9%; p = 0.056, log-rank test). Results of an "on-treatment" analysis were that patients on picotamide suffered 40 major (3.8%) and 66 minor events (6.3%), whereas those taking placebo suffered 45 major (4.2%) and 95 minor events (8.9%). The sum of both major and minor events was 106 (10.1%) in the picotamide group and 140 (13.1%) in the placebo group. This difference was significant (risk reduction, 23%; p = 0.029, log-rank test).

CONCLUSIONS

The results of this study indicate that picotamide reduces cardiovascular complications in PVD patients. The apparently low effect of this drug in reducing major events suggests that further studies be made with picotamide in PVD patients who are at high risk of cardiovascular complications so as to further assess its clinical efficacy.

Relative effectiveness of dithiol and dithiocarbamate chelating agents in reducing retention of polonium-210 in rats

Nine different sulphur-based chelators, including dithiols and dithiocarbamates, were examined for their ability to remove Po-210 from the rat. In general, treatments merely caused a redistribution of Po-210 in the body. Greatest reduction of Po-210 in blood was achieved by 2,3-dimercaptopropanol (BAL), sodium diethyldithiocarbamate (DDTC), and N-(2,3-dimercaptopropyl) phthalamidic acid (DMPA). Nearly all the compounds tested decreased Po-210 in the spleen and muscle. On the other hand, BAL and DDTC substantially increased the accumulation of Po-210 in the brain while DMPA, DMPS (sodium 2,3-dimercaptopropane-1-sulphonate) and DMSA (meso-2,3-dimercaptosuccinic acid) increased by several times the Po-210 in kidneys. A less pronounced increase of Po-210 was sometimes observed in liver (due to DDTC and DMPA) and in muscle (due to BAL and DDTC). Three of the dithiocarbamates (BGDTC, MeOBGDTC and BLDTC) did not increase accumulation of Po-210 in the brain and muscle but they reduced Po-210 in blood to a lesser degree than DDTC. A derivative of DMSA (Mi-ADMS) reduced Po-210 in blood, bone and muscle more than DMSA, but at the same time increased Po-210 in the kidney. When BAL or DDTC were combined with other agents there was a greater reduction in the whole-body burden of Po-210. Removal of Po-210 from the bone, spleen and kidneys by BAL was increased by repeated treatment. However, under similar experimental conditions the effect of a single injection of BAL on Po-210 in blood was less pronounced when the period of observation was prolonged. Total-body retention of Po-210 could not be reduced to less than 85% of the untreated controls by any of the chelators tested. In spite of this some of them (BAL, DMPS, DMSA, DMPA) could still have a useful role in reducing the toxicity of Po-210.

Chemoprevention of benzo[a]pyrene-induced forestomach cancer in mice by natural phthalides from celery seed oil

Bioassay-directed fractionation of celery seed oil from the plant Apium graveolens (Umbelliferae) led to the isolation of five natural products, including d-limonene, p-mentha-2,8-dien-1-ol, p-mentha-8(9)-en-1,2-diol, 3-n-butyl phthalide, and sedanolide. Of these compounds p-mentha-2,8-dien-1-ol,3-n-butyl phthalide, and sedanolide exhibited high activities to induce the detoxifying enzyme glutathione S-transferase (GST) in the target tissues of female A/J mice. 3-n-Butyl phthalide and sedanolide (20 mg/dose every two days for a total of 3 doses) increased GST activity 4.5-5.9 and 3.2-5.2 times over the controls in the mouse liver and small intestinal mucosa, respectively. At the same dose, p-mentha-2,8-dien-1-ol induced GST activity about 3.7-fold above that of the controls. Thus, these compounds were further tested for their ability to inhibit benzo[a]pyrene- (BP) induced tumorigenesis in mice. After treatment with 3-n-butyl phthalide and sedanolide, the tumor incidence was reduced from 68% to 30% and 11%, respectively. About 67% and 83% reduction in tumor multiplicity was also observed with 3-n-butyl phthalide and sedanolide. p-Mentha-2,8-dien-1-ol produced only a small or no significant reduction of forestomach tumor formation. The data indicating that 3-n-butyl phthalide and sedanolide were both active in tumor inhibition and GST assays suggested a correlation between the inhibitory activity and the GST-inducing ability. The phthalides are known to determine the characteristic odor of celery. The results suggest that phthalides, as a class of bioactive natural products occurring in edible umbelliferous plants, may be effective chemopreventive agents.

[The use of picotamide in nephropathy with mesangial IgA deposits. The effect on thromboxane generation]

IgA nephropathy (Berger's disease) is one of the commonest forms of glomerular disease, not rarely progressing to renal failure. Hemostatic system activation may play a role in the development of glomerular injury. In a series of 12 adult patients affected with IgA nephropathy we have observed increased plasma levels of D-dimer, a stable end-product of cross-linked fibrin degradation that is considered a reliable index of blood clotting activation, as well as "in vitro" raised generation of thromboxane, the main platelet product of arachidonic acid metabolism that seems to play an important role in glomerulosclerosis. Picotamide, a novel antiplatelet drug acting as thromboxane synthase inhibitor as well as thromboxane receptor antagonist, administered for 8-12 weeks, was effective in reducing thromboxane generation. We conclude that picotamide may be useful in the management of glomerular nephropathy.

[Evaluation of arteriolar reactivity and blood coagulation parameters during picotamide treatment]

Thirty-two patients, nineteen males and thirteen females, mean age 59.4 +/- 11.9 years, 18 with peripheral arteriopathy Fontaine stage II and 14 with cerebral vasculopathy were submitted to treatment with picotamide, 900 mg/die. In basal conditions and after 30 and 60 days of treatment, we evaluated some blood clotting parameters concerning both platelets (circulating platelet aggregates, beta-thromboglobulin, TxB2, 6-keto-pgF1 alpha) and plasma (fibrinogen, plasminogen, ATIII, Factor VIII-C and VIII Ag, prothrombin time, activated thromboplastin time) and some instrumental parameters such as walking distance and Doppler with a post-ischaemic hyperaemia test in patients with peripheral arteriopathy and Doppler of epiaortic vessels with resistance and pressure-perfusion index evaluation in patients with cerebral vasculopathy. Treatment with picotamide significantly reduced circulating platelet aggregates, beta-TG and TxB2 levels, without change of 6-keto-PGF-alpha values, with reduction of F VIII-C and slight increase of plasminogen and ATIII levels. In patients with peripheral arteriopathy after two months, a significant increase in distance and an improvement of arteriolar reactivity were observed, as shown by increase of the perfusion-index and by reduction of the post-ischaemic recovery time. These observations, together with the good tolerance of the drug, justify the use of picotamide in the treatment of patients with atherosclerotic vasculopathy at different localizations.

[Clinical efficacy of picotamide]

The effects of picotamide (300 mg b.i.d.) for secondary prevention of cerebral ischemia were compared with the effects of low-dosage aspirin (300 mg/die). Out of the 87 randomized patients, 47 completed a six month period of treatment: 29 patients in the picotamide (group P) with a mean period of 14.5 months, 18 in the aspirin group (group A) with a mean period of 15.2 months. Both showed reduced incidence of further cerebral ischemic episodes in comparison with non treated patients (literature data). Using intention-to-treat analysis, the recurrence of ischemic events (including TIA) was 5.8% in group P and 14.3% in group A. Explanatory analysis yielded similar results: 10.3% of patients in group P and 27.8% in group A had recurrence of cerebral ischemic eposides. Evaluating as endpoints only RIND and stroke, the incidence was 10.3% in group P and 16.7% in group A. In conclusion, picotamide was more effective than aspirin; however the difference was not statistically significant due to the small number of patients. The drug was well tolerated and only two patients dropped out because of side effects. Picotamide did not alter laboratory tests significantly.

[Picotamide: use in chronic obliterative arteriopathies of the lower limbs]

In the present study the authors evaluated treatment efficiency and patient compliance of medium-term therapy with Picotamide, given in doses of 900 mg/die for the first 15 days, and 600 mg/die up to the completion of a three-month period, to 50 patients affected by vaso-occlusive arterial disease of the lower limbs. At follow-up visits the following controls have been carried out: CW Doppler sonography of the lower limbs, Maximum Walking Distance (M.W.D.), Red blood cell count, White blood cell count, Platelet count, Haemoglobin and Fibrinogen levels. At the end of the three-month therapy period the Ankle-Arm parameters remained unchanged.

[Picotamide monohydrate prophylaxis of deep venous thrombosis in patients undergoing general surgery. Clinical experience]

The authors report their experience with the use of picotamide monohydrate for the prophylaxis of lower limb deep vein thrombosis in patients submitted to general surgery. Thirty-two patients were treated with the drug starting with 1200 mg daily three days before surgery and tapering to 900 mg daily in the postoperative period. The efficacy of the drug was found to be comparable to that of other currently used treatments and was not beset by a significant incidence of side effects.

[The clinico-instrumental evaluation of the efficacy of picotamide in treating chronic obstructive arteriopathies of the lower extremities]

In 25 patients (19 males and 6 females) suffering from chronic arteriopathy of lower extremities at Fontaine stage II, the clinical efficacy of picotamide was investigated in double blind, cross over placebo-controlled study. Patients were assigned randomly to the treatment with placebo or picotamide (900 mg/die) for three months and, after 15 days of wash-out, to the treatment with picotamide or placebo for the same period. Painfree walking distance and ankle/arm systolic pressure ratio improved significantly only during picotamide treatment. Laboratory monitoring revealed a significant decrease in platelet aggregation and an increase of fibrinogen degradation products only during picotamide treatment. Three patients during picotamide treatment referred transient gastrointestinal discomfort (nausea, vomiting and diarrhoea); however in no case the treatment was suspended because of the appearance of these symptoms. These results indicate that picotamide is an effective drug in the management of chronic arteriopathy of lower extremities.

[Picotamide does not interfere with the anticoagulant activity of warfarin in patients wearing heart valve prostheses]

Picotamide, a new antiplatelet drug which has only slight effects on bleeding time, could be useful, in combination with oral anticoagulants, for the prevention of thromboembolic complications in patients with heart valve prostheses. We have evaluated in a randomized, controlled, double-blind, cross-over study, the effect of picotamide on the anticoagulant activity of warfarin. Administration of 300 mg t.i.d. for 10 days to 10 patients with aortic or mitral valve prostheses did not modify significantly either the level of anticoagulation or the mean daily dosage of warfarin. We observed a trend towards a reduction of plasma levels of beta-thromboglobulin. In conclusion the results of this study show that picotamide does not interfere with the anticoagulant activity of warfarin.

Picotamide protects mice from death in a pulmonary embolism model by a mechanism independent from thromboxane suppression

We have previously characterized the new antiplatelet agent picotamide as a dual thromboxane synthase inhibitor/thromboxane A2 receptor antagonist in human platelets. We have now studied the antithrombotic activity of this drug in a simple animal model of lung platelet thromboembolism in the mouse. Picotamide, given i.p. 1 hr before the thrombotic challenge, protected mice from death caused by the i.v. injection of collagen plus epinephrine in a dose-dependent way; the dose reducing mortality by 50% was 277 mg/kg while for aspirin it was 300 mg/kg. Picotamide was also able to reduce the mortality provoked by the i.v. injection of the stable TxA2 mimetic U46619; BM 13.505, a pure TxA2-receptor blocker, was also effective while aspirin was totally inactive. Picotamide, finally, reduced the lethal consequences of the i.v. injection of a 12.5% suspension of hardened rat red blood cells, a model in which platelets are not involved; aspirin was totally ineffective in this model while nicardipine, a calcium channel blocker, was active. Picotamide did not inhibit the formation of TxB2 in serum at any of the doses tested (100 to 750 mg/kg i.p.) while it did enhance significantly PGI2-synthesis from mice aortae and, even more, from mice lungs. The i.v. administration of picotamide (250 mg/kg 2 min before the thrombotic challenge) lead to a strong inhibition of serum TxB2 (-84.6%) and was associated with a higher antithrombotic effect.(ABSTRACT TRUNCATED AT 250 WORDS)

[Alloplastic ligament replacement. A study of the biological fixation of 5 non-resorbable materials]

The long-term stability of alloplastic ligament prostheses depends on various parameters, on including the quality of the biologic fixation in the bone tissue. Biomechanical and histological tests were therefore performed to examine the stability obtained with five different alloplastic and non-resorbable ligament substitute materials following stress-free implantation into the distal femur and proximal tibia of Wistar rats. The materials were: a filament of the PTFE ligament prosthesis, PTFE suture material (Goretex), polyethylene terephthalate (Mersilene), polyethylene (Braun-Dexon) and polybutylene terephthalate (Miralene). The materials used were all of USP-1 quality. Extraction trials of the implants 32 weeks later did not show any differences between the PTFE materials, such as polyethylene and polyethylene terephthalate, whereas a significantly lower value was found for polybutylene terephthalate. The fixation involved connective tissue exclusively with all the materials tested except for PTFE. PTFE not only induced tight and direct bony contact externally, within the material itself extensive formation of new bone was also found. PTFE was found to be the most histocompatible material, while polyethylene terephthalate led to the most pronounced foreign-body-type reactions.

The use of magnetic resonance imaging in the diagnosis of triceps tendon ruptures

Triceps tendon rupture is a rare injury. Three cases are presented with a brief review of the literature. Additionally, the use of magnetic resonance imaging to facilitate the diagnosis of triceps tendon rupture is described for the first time in the English literature. Each of the three patients has done well with a Mersilene tape repair of the triceps tendon.

[Picotamide: prevention and therapy of diabetic vasculopathies. A double-blind clinical study]

Picotamide is the most interesting compound of 4-OH isophthalic acid. It is effective in vitro and in vivo. Picotamide induces inhibition of platelet aggregation: it is a thromboxane synthetase inhibitor and a thromboxane receptor antagonist. Picotamide causes cyclic endoperoxide accumulation and diverts their metabolism toward PgI2 synthesis in endothelial cells. PGI2 stimulates the adenylate cyclase with cAMP synthesis which makes platelets less sensitive to aggregatory stimulation. Picotamide induces enhancement of fibrinolytic activity, with significant reduction in the level of circulating plasminogen but in the same time it does not affect antithrombin III and FDP levels. In the present study picotamide or placebo were administered in a double blind trial at 600 mg daily for six months to 51 patients effected by diabetic macro and/or microangiopathy. The patients were 38 men and 13 women, the age was between 20 and 80 years (mean age 62.34). Twenty-seven patients were affected by type I diabetes and 24 by type II diabetes. Twenty-three of these patients presented macro-angiopathic lesions, 9 only microangiopathic lesions and 13 both. Twenty-five patients received picotamide and the other 25 an identical placebo for six months. One patient manifested myocardial infarction during the wash-out period and failed to enter the study. The following determinations were carried out: at T0 clinical examination, Doppler ultrasonography, Winsor Index, laboratory parameters; after 90 days (T90) clinical examination and Winsor Index and after 180 days (T180) were repeated photoplethysmography and clinical parameters too. Patients were not only evaluated for the vascular disease of lower extremities, but also for the other complications of diabetes, as retinopathy, nephropathy, cardiac and cerebrovascular disease.(ABSTRACT TRUNCATED AT 250 WORDS)