3,3-Disubstituted 3,4-Dihydro-1,2,4-benzotriazines: Chemistry, Biological Activity, and Affinity to Sigma Receptors

By reducing the 2-nitrophenylhydrazone of cyclohexanone with sodium dithionite, an unexpected yellow compound was obtained instead of the corresponding colorless amino derivative. Many years later, the structure of this compound, namely, cyclohexane-3-spiro-3,4-dihydro-1,2,4-benzotriazine, was demonstrated. From that time, the reduction of 2-nitrophenylhydrazones of different kinds of ketones, followed by air oxidation of the initially formed amino compounds, has represented a general way to synthesize a variety of 3,3-disubstituted 3,4-dihydro-1,2,4-benzotriazines. Many derivatives have been obtained so far by a single research group, and most of them have demonstrated interesting pharmacological activities, mainly antihypertensive, anti-inflammatory, and diuretic effects and other activities with lower diffusion. Moreover, 3,3-disubstituted 3,4-dihydro-1,2,4-benzotriazines represent a novel class of ligands for sigma receptors, with nanomolar affinity to the σ1 subtype. This property might promote the development of agents for cardiovascular, neurodegenerative, and proliferative pathologies. The present commentary, by collecting compounds and biological results obtained so far, intends to celebrate the centennial of the discovery of the first member of this class of compounds and to promote further investigation in the field.

Further Quinolizidine Derivatives as Antiarrhythmic Agents- 3

Fourteen quinolizidine derivatives, structurally related to the alkaloids lupinine and cytisine and previously studied for other pharmacological purposes, were presently tested for antiarrhythmic, and other cardiovascular effects on isolated guinea pig heart tissues in comparison to well-established reference drugs. According to their structures, the tested compounds are assembled into three subsets: (a) N-(quinolizidinyl-alkyl)-benzamides; (b) 2-(benzotriazol-2-yl)methyl-1-(quinolizidinyl)alkyl-benzimidazoles; (c) N-substituted cytisines. All compounds but two displayed antiarrhythmic activity that was potent for compounds 4, 1, 6, and 5 (in ascending order). The last compound (N-(3,4,5-trimethoxybenzoyl)aminohomolupinane) was outstanding, exhibiting a nanomolar potency (EC50 = 0.017 µM) for the increase in the threshold of ac-arrhythmia. The tested compounds shared strong negative inotropic activity; however, this does not compromise the value of their antiarrhythmic action. On the other hand, only moderate or modest negative chronotropic and vasorelaxant activities were commonly observed. Compound 5, which has high antiarrhythmic potency, a favorable cardiovascular profile, and is devoid of antihypertensive activity in spontaneously hypertensive rats, represents a lead worthy of further investigation.

Thioxanthenone-based derivatives as multitarget therapeutic leads for Alzheimer's disease

A set of twenty-five thioxanthene-9-one and xanthene-9-one derivatives, that were previously shown to inhibit cholinesterases (ChEs) and amyloid β (Aβ₄₀) aggregation, were evaluated for the inhibition of tau protein aggregation. All compounds exhibited a good activity, and eight of them (5-8, 10, 14, 15 and 20) shared comparable low micromolar inhibitory potency versus Aβ₄₀ aggregation and human acetylcholinesterase (AChE), while inhibiting human butyrylcholinesterase (BChE) even at submicromolar concentration. Compound 20 showed outstanding biological data, inhibiting tau protein and Aβ₄₀ aggregation with IC₅₀ = 1.8 and 1.3 μM, respectively. Moreover, at 0.1-10 μM it also exhibited neuroprotective activity against tau toxicity induced by okadoic acid in human neuroblastoma SH-SY5Y cells, that was comparable to that of estradiol and PD38. In preliminary toxicity studies, these interesting results for compound 20 are somewhat conflicting with a narrow safety window. However, compound 10, although endowed with a little lower potency for tau and Aβ aggregation inhibition additionally demonstrated good inhibition of ChEs and rather low cytotoxicity. Compound 4 is also worth of note for its high potency as hBChE inhibitor (IC₅₀ = 7 nM) and for the three order of magnitude selectivity versus hAChE. Molecular modelling studies were performed to explain the different behavior of compounds 4 and 20 towards hBChE. The observed balance of the inhibitory potencies versus the relevant targets indicates the thioxanthene-9-one derivatives as potential MTDLs for AD therapy, provided that the safety window will be improved by further structural variations, currently under investigation.

Optimization of the clofazimine structure leads to a highly water-soluble C3-aminopyridinyl riminophenazine endowed with improved anti-Wnt and anti-cancer activity in vitro and in vivo

Triple-negative breast cancer (TNBC) is a cancer subtype critically dependent upon excessive activation of Wnt pathway. The anti-mycobacterial drug clofazimine is an efficient inhibitor of canonical Wnt signaling in TNBC, reducing tumor cell proliferation in vitro and in animal models. These properties make clofazimine a candidate to become first targeted therapy against TNBC. In this work, we optimized the clofazimine structure to enhance its water solubility and potency as a Wnt inhibitor. After extensive structure-activity relationships investigations, the riminophenazine 5-(4-(chlorophenyl)-3-((2-(piperazin-1-yl)ethyl)imino)-N-(pyridin-3-yl)-3,5-dihydrophenazin-2-amine (MU17) was identified as the new lead compound for the riminophenazine-based targeted therapy against TNBC and Wnt-dependent cancers. Compared to clofazimine, the water-soluble MU17 displayed a 7-fold improved potency against Wnt signaling in TNBC cells resulting in on-target suppression of tumor growth in a patient-derived mouse model of TNBC. Moreover, allowing the administration of reduced yet effective dosages, MU17 displayed no adverse effects, most notably no clofazimine-related skin coloration.

Benzimidazole derivatives endowed with potent antileishmanial activity

Two sets of benzimidazole derivatives were synthesised and tested in vitro for activity against promastigotes of Leishmania tropica and L. infantum. Most of the tested compounds resulted active against both Leishmania species, with IC50 values in the low micromolar/sub-micromolar range. Among the set of 2-(long chain)alkyl benzimidazoles, whose heterocyclic head was quaternised, compound 8 resulted about 100-/200-fold more potent than miltefosine, even if the selectivity index (SI) versus HMEC-1 cells was only moderately improved. In the set of 2-benzyl and 2-phenyl benzimidazoles, bearing a basic side chain in position 1, compound 28 (2-(4-chlorobenzyl)-1-lupinyl-5-trifluoromethylbenzimidazole) was 12-/7-fold more potent than miltefosine, but exhibited a further improved SI. Therefore, compounds 8 and 28 represent interesting hit compounds, susceptible of structural modification to improve their safety profiles.

New arylsparteine derivatives as positive inotropic drugs

Positive inotropic agents are fundamental in the treatment of heart failure; however, their arrhythmogenic liability and the increased myocardial oxygen demand strongly limit their therapeutic utility. Pursuing our study on cardiovascular activities of lupin alkaloid derivatives, several 2-(4-substituted-phenyl)-2-dehydrosparteines and 2-(4-substituted-phenyl)sparteines were prepared and tested for inotropic and chronotropic activities on isolated guinea pig atria. Four compounds (6b, 6e, 7b, and 7f) exhibited significant inotropism that, at the higher concentrations, was followed by negative inotropism or toxicity. Compound 7e (2-(4-tolyl)sparteine) exhibited a steep dose-depending inotropic activity up to the highest concentration tested (300 µM) with an E_max of 116.5 ± 3.4% of basal force, proving less potent but much more active in comparison to the highest concentrations tested of digoxin and milrinone having E_max of 87.5 ± 3.1% and 52.2 ± 1.1%, respectively. Finally, docking studies suggested that the relevant sparteine derivatives could target the sigma-1 receptor, whose involvement in cardiac activity is well documented.

Antiviral activity of benzotriazole derivatives. 5-[4-(Benzotriazol-2-yl)phenoxy]-2,2-dimethylpentanoic acids potently and selectively inhibit Coxsackie Virus B5

A library of 64 benzotriazole derivatives (17 of which were [4-(benzotriazol-2-yl)phenoxy]alkanoic acids) were screened for antiviral activity against a panel of twelve DNA and RNA viruses. Twenty-six compounds (12 of which were [4-(benzotriazol-2-yl)phenoxy]alkanoic acids) displayed activity against one or more viruses. CVB-5, RSV, BVDV, Sb-1 and YFV were, in decreasing order, the more frequently and effectively affected viruses; DENV-2, WNV, HIV-1 and Reo-1 were only occasionally and modestly affected, while the remaining viruses were not affected by any of the tested compounds. Worth of note were compounds 33 and 35; the former for the activity against Sb-1 (EC50=7 μM) and the latter for the large spectrum of activity including six viruses with a mean EC50=12 μM. Even more interesting were the alkanoic acids 45-48 and 50-57 for their activity against RSV and/or CVB-5. In particular, compound 56 displayed a potent and selective activity against CVB-5 with EC50=0.15 μM and SI=100, thus representing a valuable hit compound for the development of antiviral agents for the treatment of human pathologies related to this virus.

Synthesis and Antiplasmodial Activity of Novel Chloroquine Analogues with Bulky Basic Side Chains

Chloroquine is commonly used in the treatment and prevention of malaria, but Plasmodium falciparum, the main species responsible for malaria-related deaths, has developed resistance against this drug. Twenty-seven novel chloroquine (CQ) analogues characterized by a side chain terminated with a bulky basic head group, i.e., octahydro-2H-quinolizine and 1,2,3,4,5,6-hexahydro-1,5-methano-8H-pyrido[1,2-a][1,5]diazocin-8-one, were synthesized and tested for activity against D-10 (CQ-susceptible) and W-2 (CQ-resistant) strains of P. falciparum. Most compounds were found to be active against both strains with nanomolar or sub-micromolar IC50 values. Eleven compounds were found to be 2.7- to 13.4-fold more potent than CQ against the W-2 strain; among them, four cytisine derivatives appear to be of particular interest, as they combine high potency with low cytotoxicity against two human cell lines (HMEC-1 and HepG2) along with easier synthetic accessibility. Replacement of the 4-NH group with a sulfur bridge maintained antiplasmodial activity at a lower level, but produced an improvement in the resistance factor. These compounds warrant further investigation as potential drugs for use in the fight against malaria.

Multitarget Therapeutic Leads for Alzheimer's Disease: Quinolizidinyl Derivatives of Bi- and Tricyclic Systems as Dual Inhibitors of Cholinesterases and β-Amyloid (Aβ) Aggregation

Multitarget therapeutic leads for Alzheimer's disease were designed on the models of compounds capable of maintaining or restoring cell protein homeostasis and of inhibiting β-amyloid (Aβ) oligomerization. Thirty-seven thioxanthen-9-one, xanthen-9-one, naphto- and anthraquinone derivatives were tested for the direct inhibition of Aβ(1-40) aggregation and for the inhibition of electric eel acetylcholinesterase (eeAChE) and horse serum butyrylcholinesterase (hsBChE). These compounds are characterized by basic side chains, mainly quinolizidinylalkyl moieties, linked to various bi- and tri-cyclic (hetero)aromatic systems. With very few exceptions, these compounds displayed inhibitory activity on both AChE and BChE and on the spontaneous aggregation of β-amyloid. In most cases, IC50 values were in the low micromolar and sub-micromolar range, but some compounds even reached nanomolar potency. The time course of amyloid aggregation in the presence of the most active derivative (IC50 =0.84 μM) revealed that these compounds might act as destabilizers of mature fibrils rather than mere inhibitors of fibrillization. Many compounds inhibited one or both cholinesterases and Aβ aggregation with similar potency, a fundamental requisite for the possible development of therapeutics exhibiting a multitarget mechanism of action. The described compounds thus represent interesting leads for the development of multitarget AD therapeutics.

(+)-Laburnamine, a natural selective ligand and partial agonist for the α4β2 nicotinic receptor subtype

(+)-Laburnamine (1), a rare alkaloid extracted from Laburnum anagyroides seeds (∼4 mg from 1 kg), was shown to bind with high affinity (Ki, 293 nM) to the α4β2 nicotinic receptor subtype, which is, respectively, 126 and 136 times higher than to the α3β4 (Ki 37 μM) and α7 subtypes (Ki 40 μM). When its ability to release [(3)H]-dopamine from striatal slices was tested in a functional assay, compound 1 behaved as a partial agonist with an EC50 of 5.8 μM and an Emax that was 43% that of nicotine. When incubated with nicotine in the same assay, 1 prevented a maximal effect from being reached.

CC4, a dimer of cytisine, is a selective partial agonist at α4β2/α6β2 nAChR with improved selectivity for tobacco smoking cessation

BACKGROUND AND PURPOSE

Many of the addictive and rewarding effects of nicotine are due to its actions on the neuronal nicotinic ACh receptor (nAChR) subtypes expressed in dopaminergic mesocorticolimbic cells. The partial agonists, cytisine and varenicline, are helpful smoking cessation aids. These drugs have a number of side effects that limit their usefulness. The aim of this study was to investigate the preclinical pharmacology of the cytisine dimer1,2-bisN-cytisinylethane (CC4).

EXPERIMENTAL APPROACH

The effects of CC4 on nAChRs were investigated using in vitro assays and animal behaviours.

KEY RESULTS

When electrophysiologically tested using heterologously expressed human subtypes, CC4 was less efficacious than cytisine on neuronal α4β2, α3β4, α7 and muscle-type receptors, and had no effect on 5-hydroxytryptamine3 receptors. Acting through α4β2 and α6β2 nAChRs, CC4 is a partial agonist of nAChR-mediated striatal dopamine release and, when co-incubated with nicotine, prevented nicotine's maximal effect on this response. In addition, it had low affinity for, and was less efficacious than nicotine and cytisine on the α3β4 and α7-nAChR subtypes. Like cytisine and nicotine, CC4-induced conditioned place preference (CPP), and its self-administration shows an inverted-U dose-response curve. Pretreatment with non-reinforcing doses of CC4 significantly reduced nicotine-induced self-administration and CPP without affecting motor functions.

CONCLUSION AND IMPLICATIONS

Our in vitro and in vivo findings reveal that CC4 selectively reduces behaviours associated with nicotine addiction consistent with the partial agonist selectivity of CC4 for β2-nAChRs. The results support the possible development of CC4 or its derivatives as a promising drug for tobacco smoking cessation.

Antiviral and cytotoxic activities of aminoarylazo compounds and aryltriazene derivatives

Twelve aminoarylazocompounds (A-C) and 46 aryltriazene 7 derivatives (D-G) have been synthesized and evaluated in cell-based assays for cytotoxicity and antiviral activity against a panel of 10 RNA and DNA viruses. Eight aminoazocompounds and 27 aryltriazene derivatives exhibited antiviral activity, sometimes of high level, against one or more viruses. A marked activity against BVDV and YFV was prevailing among the former compounds, while the latter type of compounds affected mainly CVB-2 and RSV. None of the active compounds inhibited the multiplication of HIV-1, VSV and VV. Arranged in order of decreasing potency and selectivity versus the host cell lines, the best compounds are the following; BVDV: 1>7>8>4; YFV: 7>5; CVB-2: 25>56>18; RSV: 14>20>55>38>18>19; HSV-1: 2. For these compounds the EC(50) ranged from 1.6 microM (1) to 12 microM (18), and the S. I. from 19.4 (1) to 4.2 (2). Thus the aminoarylazo and aryltriazene substructures appear as interesting molecular component for developing antiviral agents against ss RNA viruses, particularly against RSV and BVDV, which are important human and veterinary pathogens. Finally, molecular modeling investigations indicated that compounds of structure A-C, active against BVDV, could work targeting the viral RNA-dependent RNA-polymerase (RdRp), having been observed a good agreement between the trends of the estimated IC(50) and the experimental EC(50) values.

Organometallic compounds in oncology: implications of novel organotins as antitumor agents

Since the introduction of cisplatin in cancer therapy, metal complexes and organometallic compounds have been gaining growing importance in oncology. The impressive clinical effectiveness of cisplatin is limited by significant side effects and the emergence of drug resistance. Thus, novel classic and unconventional Pt(II) and Pt(IV) complexes have been introduced in therapy or are presently in advanced clinical trials. Moreover, innovative non-platinum metal-based antitumor agents, whose activity does not rely on direct DNA damage and may involve proteins and enzymes, have been developed. Gold and tin derivatives are enjoying an increasing interest and appear very promising as potential drug candidates.

Antimicrobial and cytotoxic arylazoenamines. Part III: antiviral activity of selected classes of arylazoenamines

Eighty-five arylazoenamines, characterized by different types of aryl and basic moieties, have been synthesized and evaluated in cell-based assays for cytotoxicity and antiviral activity against a panel of ten RNA and DNA viruses. The most commonly affected viruses were, in decreasing order, CVB-2, RSV, BVDV, YFV, and Sb-1; the remaining viruses were either not affected (HIV-1, VSV, and VV) or susceptible only to a very few compounds (Reo-1 and HSV-1). Thirty-five compounds exhibited high activity, with EC(50) in the range 0.8-10 microM, and other 28 compounds had EC(50) between 11 and 30 microM, thus indicating that the arylazoenamine molecular pattern is an interesting novel pharmacophore for antiviral agents against ssRNA viruses. Moreover, some compounds (as 28, 32, 42, and 53) appear of high interest, being devoid of toxicity on the human MT-4 cells (CC(50)>100 microM). A ligand-based computational approach was employed to identify highly predictive pharmacophore models for the most frequently affected viruses CVB-2, RSV, and BVDV. These models should allow the design of second generation of more potent inhibitors of these human and veterinary pathogens.

Antimalarial activity of novel pyrrolizidinyl derivatives of 4-aminoquinoline

Two pyrrolizidinylalkyl derivatives of 4-amino-7-chloroquinoline (MG2 and MG3) were prepared and tested in vitro against CQ-sensitive and CQ-resistant strains of Plasmodium falciparum and in vivo in a Plasmodium berghei mouse model of infection. Both compounds exhibited excellent activity in all tests and low toxicity against mammalian cells. Preliminary studies of the acute toxicity and of the metabolism of the most active compound MG3 indicate a promising profile as a new antimalarial drug candidate.

Cholecystoduodenal fistula in a nonagenarian. Can laparotomy play a role in the era of laparoscopic? Case report

Cholecystoduodenal fistula, a rare complication of biliary lithiasis, occurs in 0.5% to 3% of patients affected by cholelithiasis. Diagnosis is not easy and is usually incidental at surgery. The literature guidelines call for a laparoscopic approach to treating these patients; here, however, we report a case of a very elderly patient in which, among other reasons, open surgery was the treatment of choice to decrease morbidity and mortality.

Alpha1- and alpha2-adrenoreceptor antagonist profiles of 1- and 2-[omega-(4-arylpiperazin-1-yl)alkyl]-1,2,3-benzotriazoles

A series of pharmacologically interesting 1- and 2-[omega-(4-arylpiperazin-1-yl)alkyl]-1,2,3-benzotriazoles, compounds 1-27, were synthesized (Scheme) and subjected to various biological studies to identify structure-activity relationships (SAR). The new compounds were found to exhibit good non-selective binding affinity towards the alpha1-adrenoreceptor (Table 1). In several cases, high functional antagonism was observed towards the alpha1A-, alpha1B-, and alpha1D-adrenoreceptor subtypes (Table 2). The selectivity for these three subtypes was comparable with or superior to that displayed by the standard drug prazosin. The most-common selectivity rank order was alpha1D > alpha1B > alpha1A, followed by alpha1B > alpha1D > alpha1A. In functional experiments, antagonism towards the alpha2-adrenoreceptor was generally low; however, a few compounds were endowed with significant antagonist properties (pA2 values of up to 7.87).

Novel Quinolizidinyl Derivatives as Antiarrhythmic Agents

Eighteen analogues of lidocaine, mexiletine, and procainamide were synthesized, replacing their aminoalkyl chains with the rigid and cumbersome quinolizidine nucleus. The target compounds were tested for antiarrhythmic, inotropic, and chronotropic effects on isolated guinea pig (gp) heart tissues and to assess calcium antagonist activity. Most compounds exhibited from moderate to high antiarrhythmic activity, and compounds 7, 9, and 19 were more active and potent than quinidine and lidocaine, while producing only modest inotropic, chronotropic, and vasorelaxant effects. These compounds were studied on spontaneously beating Langendorff-perfused gp heart. While quinidine and amiodarone produced a dose-dependent prolongation of all the ECG intervals, compounds 7, 9, and 19, even at concentrations 10-20 times higher than EC50 for the antiarrhythmic activity, only moderately prolonged the PR and QT intervals, leaving unchanged the QRS complex. Ether 7 deserves further investigations due to its interesting cardiovascular profile.

Long-term exposure to the new nicotinic antagonist 1,2-bisN-cytisinylethane upregulates nicotinic receptor subtypes of SH-SY5Y human neuroblastoma cells

Nicotinic drug treatment can affect the expression of neuronal nicotinic acetylcholine receptors (nAChR) both in vivo and in vitro through molecular mechanisms not fully understood. The present study investigated the effect of the novel cytisine dimer 1,2-bisN-cytisinylethane (CC4) on nAChR natively expressed by SH-SY5Y neuroblastoma cells in culture. CC4 lacked the agonist properties of cytisine and was a potent antagonist (IC50=220 nM) on nAChRs. Chronic treatment of SH-SY5Y cells with 1 mM CC4 for 48 h increased the expression of 3H-epibatidine (3H-Epi; 3-4-fold) or 125I-alpha-bungarotoxin (125I-alphaBgtx; 1.2-fold) sensitive receptors present on the cell membrane and in the intracellular pool. Comparable data were obtained with nicotine or cytisine, but not with carbamylcholine, d-tubocurarine, di-hydro-beta-erythroidine or hexametonium. Immunoprecipitation and immunopurification studies showed that the increase in 3H-Epi-binding receptors was due to the enhanced expression of alpha3beta2 and alpha3beta2beta4 subtypes without changes in subunit mRNA transcription or receptor half-life. The upregulation was not dependent on agonist/antagonist properties of the drugs, and did not concern muscarinic or serotonin receptors. Whole-cell patch clamp analysis of CC4-treated cells demonstrated larger nicotine-evoked inward currents with augmented sensitivity to the blockers alpha-conotoxin MII or methyllycaconitine. In conclusion, chronic treatment with CC4 increased the number of nAChRs containing beta2 and alpha7 subunits on the plasma membrane, where they were functionally active. In the case of beta2-containing receptors, we propose that CC4, by binding to intracellular receptors, triggered a conformational reorganisation of intracellular subunits that stimulated preferential assembly and membrane-directed trafficking of beta2-containing receptor subtypes..

Isolated hydatid cyst of the diaphragm without liver or lung involvement: a case report

The most common targets of the echinococcus are the liver and the lung, but several organs can be affected by this disease. The isolated diaphragmatic location of the cyst, not associated with liver or lung, is very rare. The aim of this work is to report a case of hydatid cyst located in the abdominal side of the diaphragm and to review the literature. The diagnosis was fortuitous and at CT scan the cyst was apparently located on segment VII of the liver. During surgery, after dissection of the adherences with the liver, the cyst remained attached to the diaphragm. Thirty months after the resection, the patient is free of symptoms without any recurrence.

Emergency gastric ulcer complications in elderly. Factors affecting the morbidity and mortality in relation to therapeutic approaches

AIM

In elderly the incidence of the emergency gastric ulcer complications, perforation and bleeding are increasing, with a difficult management of these patients for their concomitant diseases. The aim of this work is to analyze the therapeutical approach of emergency gastric ulcer complications in elderly patients, in order to establish the factors affecting the morbidity and mortality.

METHODS

Patients older than 70 years, presenting gastric ulcer, observed in a tertiary University Hospital from 1995 to 2003, have been considered for the present study. Two groups of diseases have been examined: ulcer perforation and bleeding ulcer. Age, sex, risk factors, comorbidity, methods of diagnosis, ulcer characteristics, treatment, morbidity, mortality, hospitalization time and follow-up have been considered in each group.

RESULTS

Thirteen elderly patients with perforated gastric ulcer have been observed: 9 (69.2%) females and 4 (30.8%) males with a mean age of 80.5 years (range 70-90). Four patients were hospitalized in suburban hospital with an average time between the diagnosis and the surgery of 36 h, while the remnants were hospitalized directly in our Department with a medium waiting time of about 2 h. The surgical procedures were: simple closure with omentum patch in 11 cases (84.6%), and antrectomy in 2 cases (15.4%), in which the antrum was multiply perforated. Two patients presented an ulcer larger than 2 cm treated with simple suture and omental patch without morbidity and mortality. Three patients (23%) died postoperatively, due to septic shock, ventricular fibrillation and intraoperative massive haemorrhage, 2 of these patients came from other hospitals. Twenty-eight elderly patients with bleeding gastric ulcer have been observed during the same period: 13 (46.4%) females and 15 (53.6%) males with a mean age of 79.6 years (range 71-91). Except 2 patients submitted to endoscopic treatment both with adrenaline injection, all the remnant patients were managed with medical therapy (H2-receptor antagonist or proton pump inhibitors and in 7 patients [24.1%] antihaemorrhage drugs), and clinical observation, with a endoscopic control 3-4 days after from the first endoscopy. One of the 2 patients endoscopically treated developed a ulcer perforation after 11 days, and the other one rebled, without possibility of any kind of treatment due to his instable condition of health. Three patients (10.7%) died during their hospital stay not for causes strictly due to the gastric haemorrhage.

CONCLUSIONS

Our results suggest that the early diagnoses and early treatment are 2 basic factor on the prognosis of elderly patients with perforated gastric ulcer. The choice between simple closure, with or without vagotomy, or gastrectomy depends from preoperative and operative health conditions of the patient. In patients with ulcer larger than 2 cm, Graham's technique can be performed safely if the preoperative and intraoperative conditions are favourable. Elderly patients with gastric ulcer bleeding show an high risk of morbidity and mortality, related to the risk factors like non steroid anti-inflammatory drugs (NSAIDs) intake or smoke. Repeated endoscopy and antiulcer drugs can manage the high stage patients of Forrest's classification with a low rate of morbidity and mortality. According to literature surgical treatment should be reserved after the second failure of endoscopic treatment.

4-Aminoquinoline quinolizidinyl- and quinolizidinylalkyl-derivatives with antimalarial activity

A set of quinolizidinyl and quinolizidinylalkyl derivatives of 4-amino-7-chloroquinoline and of 9-amino-6-chloro-2-methoxyacridine were prepared and tested in vitro against CQ-sensitive (D-10) and CQ-resistant (W-2) strains of Plasmodium falciparum. All compounds but one exerted significant antimalarial activity. Some of the quinolizidine derivatives were from 5 to 10 times more active than chloroquine on the CQ-resistant strain. No toxicity against mammalian cells was observed.

[Use of the Floating Ball for hepatic resection in cirrhotic patients affected by hepatocellular carcinoma]

Done to the improvement of knowledges in hepatic surgery and postoperative care, hepatocellular carcinoma (HCC) have been treated more and more frequently by hepatic resection. Aim of this study is to report an initial series of patients affected by HCC treated by hepatic resection utilizing a new water-cooled, high-density, monopolar device, the Tissuelink Monopolar Floating Ball (Tissuelink Medical Inc., Dover, NH, U.S.A.), in order to avoid bleeding during hepatic surgery. Sex, age, kind of disease, viral and Child status, type of surgical procedure, in association to lenght of surgical procedure, blood loss, utilization of the vascular clamping of the liver, hospital stay, morbidity and mortality have been analized. Six liver resections have been performed utilizing this new device. No vascular clamping was established except one. No mortality was recorded. Morbidity was ascites in one case and pleural effusion in a second one. In conclusion the Floating Ball reduces the intraoperative bleeding during hepatic resection in patients with HCC.

[Assessment of patient's comfort and functioning of a totally implantable venous system placed in the safenous vein]

BACKGROUND

When venous system of superior vena cava is not useful or when chest wall is not utilizable to place a reservoir, saphenous vein can be utilized for totally implantable venous access device (TIVAD) placement. Aim of this work is to establish the best location of the reservoir for the function and the comfort of the patient.

PATIENTS AND METHODS

All the patients submitted to TIVAD placement from January 1995 to October 2004 at the Department of Surgical Science, Organs Transplantations and Advanced Technologies of University of Catania have been considered to the present study. Age, sex, kind of disease, surgical procedure, early and late complications, function of the system and comfort to the patients in relation to the different site of reservoir placement have been studied.

RESULTS

447 TIVAD have been implanted in 258 males and 189 females aged from 31 to 79 years in the period considered for the study. Solid tumors represent the majority of the indications and all the TIVAD have been implanted by surgical cutdown to avoid all the early complications related to the percutaneous approach. Two patients received their TIVAD using saphenous vein by surgical cut-down, and no early complications have been recorded. The reservoirs have been placed respectively: in the chest wall in the first patient; and in the anterior wall of the abdomen, close to the anterosuperior iliac crest, firstly and later in the anterolateral face of the thigh in the second one. The first patient had non complications instead the second one referred discomfort with both reservoir locations.

CONCLUSIONS

For the comfort of the patient related to the reservoir position in case of saphenous vein utilization chest wall should represent the best studies are required to validate the appropriate reservoir location.

Subclavian vein stenosis following totally implantable venous access device (TIVAD) implant by percutaneous approach. Case report

Totally implantable venous access devices (TIVADs) are more and more used in oncologic patients. Early and late complications frequently occur with the techniques of implantation. Thrombosis is the most important and common late complication. On the opposite stenosis of the vessel is not frequently reported. The Authors report the case of a patient with subclavian vein stenosis after implantation of a TIVAD by percutaneous technique. On the basis of the published knowledges they try to explain this phenomenon and suggest an hypothesis for future works.

2-Phenyl-3-(quinolizidin-1-yl)-5-substituted indoles as platelet antiaggregating agents

A set of ten 2-phenyl-3-(quinolizidin-1-yl)-5-substituted indoles was prepared through the Fischer cyclization of lupinyl- and epi-lupinylphenylketone 4-substituted phenylhydrazones. Compounds were tested for antiaggregating activity on human platelets activated by adenosine diphosphate (ADP), collagen and adrenaline. At 2.5 x 10(-4) M concentration most compounds strongly inhibited the aggregation induced by all the agonists considered and many of them still displayed good activity at 0.625 x 10(-4) M concentration. The least active (1c) and one of the most active (1d) compounds were also tested for antiaggregating activity on rabbit platelets activated by ADP, PAF and sodium arachidonate. Both the compounds were active against ADP and PAF, but only 1d inhibited the arachidonate-induced aggregation (100% at 8 x 10(-6) M concentration) and increased the bleeding time in mice. The same compounds were subjected to a general pharmacological screening and found to display several activities; of particular interest was the dose dependent reduction of serum cholesterol and heparin precipitating betalipoproteins in hypercholesterolemic mice exerted by 1c, which was still significant at the oral dose of 10 mg/kg.

[Rule of early diagnosis for sigmoid volvulus. Case report]

The sigmoid colon is the most frequent site for a volvulus due to anatomical and pathological reasons. When the rotation of the loop occurs slowly, the sigma can greatly blow up and stretch. We report the clinical case of an 80-year-old woman admitted to our Department for an enormous volvulus of sigmoid colon. Physical examination, abdominal X-ray and CT-scan were performed to diagnose the disease. At the surgical procedure the sigma was about 50 centimetres in length and 15 centimetres in diameter, with a gangrenous necrosis of the loop; the treatment was a sigmoidectomy by Hartmann procedure. Surgical resection is the only therapeutical option for volvulus in advanced stage due to a late diagnosis.

Novel sigma binding site ligands as inhibitors of cell proliferation in breast cancer

Sigma receptors, namely sigma1 and sigma2, have been shown to be expressed in a variety of human cell lines playing a role in cell growth. In the human breast, they are absent in normal mammary tissue but expressed in tumors, particularly in the proliferating stage. The study presented here concerns nine newly synthesized ligands for sigma receptors. The compounds are of general structure consisting of: five (1alpha/1beta-arylalkyl)quinolizidines including two thioisosteres and four spiro-[3,4-dihydro-1,2,4-benzotriazino-3,4'-(1'-substituted) piperidines]. These compounds exhibited varying degrees of affinity for sigma receptors and were able to inhibit the growth of MCF-7 and MDA-MB 231 human breast cancer cell lines, in vitro. Good to moderate binding to at receptors occurred with all tested ligands. However, affinity for sigma2 appeared more evident with compounds FN/C-2 and FN/C-4 (spiro-[3,4-dihydro-1,2,4-benzotriazino-3,4'-(1'-substituted) piperidines] derivatives). In addition, higher cytotoxic activity of FN/C-2 and FN/C-4 with IC50 values below 100 microM in MCF-7 and lower than 40 microM in MDA-MB 231 was revealed. The data from the current study show that these novel sigma receptor ligands exhibit interesting cytotoxic activity and suggest their potential for development as antitumor agents.

Quinolizidinyl derivatives of iminodibenzyl and phenothiazine as multidrug resistance modulators in ovarian cancer cells

The development of multidrug-resistance (MDR) in neoplastic cells is often responsible for the therapy failure and poor outcome of a number of human cancers. MDR may be associated with the expression of the multidrug transporter glycoprotein p170, encoded by the MDR1 gene, which acts as an ATP-dependent efflux pump by reducing the intracellular accumulation of some cytotoxic agents. A variety of iminodibenzyl and phenothiazine derivatives, characterized by the presence of a bicyclic, strongly basic, and highly lipophilic quinolizidine nucleus, were synthesized to investigate their ability to modulate the MDR phenotype. A set of 10 of them (named 1-10), bearing quinolizidine moiety linked through different connecting chains, were tested as chemoresistance-reversing agents on doxorubicin-resistant ovarian cancer cells (A2780-DX3). A 51-fold resistance to doxorubicin was reported in the A2780-DX3 compared to the parental sensitive A2780 WT with mean IC(50) values of 0.02 and 1.02 muM, respectively. Moreover, overexpression of the glycoprotein p170 in the resistant cell line was detected by Western blot analysis. By cytotoxicity assays and time-course experiments, different treatment schedules with resistance modulators (including clomipramine as reference drug) and doxorubicin were taken into account. The 16 h exposure of cells to 1 muM of modulator before doxorubicin demonstrated to be superior in sensitizing the resistant cell line. In particular, compounds 8, 7, 10, and 4 increasingly potentiated doxorubicin cytotoxicity, up to 5.6-fold in A2780-DX3 cells. The present results suggest promising indications for further development of these compounds as chemosensitizing drugs.

N-Homolupinanoyl and N-(ω-lupinylthio)alkanoyl derivatives of some tricyclic systems as ligands for muscarinic M1 and M2 receptor subtypes

A set of N-homolupinanoyl- and N-(omega-lupinylthio)alkanoyl derivatives of tricyclic systems (as phenothiazine, iminodibenzyl and dihydropyridobenzodiazepinone) has been prepared and tested for affinity for rat muscarinic M(1) and M(2) receptor subtypes labeled with [3H]pirenzepine and [3H]AF-DX 384. Good affinity for both M(1) and M(2) subtypes was displayed by most compounds, often with nanomolar K(i) values, which for lupinylthiopropionyl- and lupinylthiobutyryl-phenothiazines (13-16) were comparable to those of pirenzepine and methoctramine, respectively. However, only moderate selectivity for one or the other subtype was seen.

Nitrogen substitution modifies the activity of cytisine on neuronal nicotinic receptor subtypes

Cytisine very potently binds and activates the alpha 3 beta 4 and alpha 7 nicotinic subtypes, but only partially agonises the alpha 4 beta 2 subtype. Although with a lower affinity than cytisine, new cytisine derivatives with different substituents on the basic nitrogen (CC1-CC8) bind to both the heteromeric and homomeric subtypes, with higher affinity for brain [3H]epibatidine receptors. The cytisine derivatives were tested on the Ca(2+) flux of native or transfected cell lines expressing the rat alpha 7, or human alpha 3 beta 4 or alpha 4 beta 2 subtypes using Ca(2+) dynamics in conjunction with a fluorescent image plate reader. None elicited any response at doses of up to 30-100 microM, but all inhibited agonist-induced responses. Compounds CC5 and CC7 were also electrophysiologically tested on oocyte-expressed rat alpha 4 beta 2, alpha 3 beta 4 and alpha 7 subtypes. CC5 competitively antagonised the alpha 4 beta 2 and alpha 3 beta 4 subtypes with similar potency, whereas CC7 only partially agonised them with maximum responses of respectively 3% and 11% of those of 1 mM acetylcholine. Neither compound induced any current in the oocyte-expressed alpha 7 subtype, and both weakly inhibited acetylcholine-induced currents. Adding chemical groups of a different class or size to the basic nitrogen of cytisine leads to compounds that lose full agonist activity on the alpha 3 beta 4 and alpha 7 subtypes.

Cytisine derivatives as ligands for neuronal nicotine receptors and with various pharmacological activities

Neuronal nicotinic acetylcholine receptors (nAChRs) form a family of ACh-gated cation channels made up of different subtypes. They are widely distributed in peripheral and central nervous systems and are involved in complex cerebral processes as learning, memory, nociception, movement, etc. The possibility that subtype-selective ligands be used in the treatment of CNS disorders promoted the synthesis of a large number of structural analogues of nicotine and epibatidine, two very potent nAChR agonists. Pursuing our long standing research on the structural modification of quinolizidine alkaloids, we devoted our attention to cytisine, another very potent ligand for many nAChR subtypes. Thus a systematic structural modification of cytisine was undertaken in order to obtain compounds of potential therapeutic interest at peripheral as well as central level, with a particular concern for achieving nAChR subtype selective ligands. Up to the present more than 80 cytisine derivatives, mainly of N-substitution and a few by modifying the pyridone ring, have been prepared. The biological results, which concern so far about an half of the prepared compounds, indicate that the introduction of a nitro group in position 3 of the pyridone nucleus further enhances the high affinity of cytisine, while the introduction of substituents on the basic nitrogen, though reducing in different degrees the affinity, gives rise to compounds with a higher selectivity for central (alpha(4)beta(2)) versus gangliar (alpha(3)-containing) receptor subtype. On the other hand, the analgesic, antihypertensive and inotropic activities found in some N-substituted cytisines, represent an attractive starting point for the development of more active compounds.

Antiinflammatory and antinociceptive activities of some benzotriazolylalkanoic acids

Sets of benzotriazol-1/2-ylalkanoic acids (1, 2, 3) and benzotriazol-1-yloxyalkanoic acids (4, 5) were prepared and tested for antiinflammatory activity; when significant activity was observed also the antinociceptive activity was explored. While the acids of structure 1, 4 and 5 were devoid of antiinflammatory action, most 2-(benzotriazol-1/2-yl)propionic acids (2, 3) exhibited significant activity as antiinflammatory and antinociceptive agents, with compound 2c and 3a being the most active in the two assays, respectively. The dextrorotatory enantiomer of 2c ((+)-2c) was also prepared and found to be practically as active as the racemic mixture, though some differences in the steepness of the dose-response curves were observed.

Chemosensitivity of glioblastoma cells during treatment with the organo-tin compound triethyltin(IV)lupinylsulfide hydrochloride

Malignant gliomas are the most common primary brain tumors in humans. However, poor response to conventional therapeutic approaches, including chemotherapy, leads invariably to disease recurrence and progression. The organo-tin derivative triethyltin(IV)lupinylsulfide hydrochloride (IST-FS 29) was identified and developed as potential antiproliferative agent in human cancer cell lines. However, for its peculiar chemical structure and good lipophilicity, this compound also appeared an eligible candidate for the treatment of gliobastoma cells. The present experiments were designed to explore the in vitro effects of IST-FS 29 on four human glioblastoma cell lines: A-172, DBTRG.05MG, U-87MG and CAS-1. The average IC50 values were obtained by MTT assay and ranged between 3 and 10 microM. Time-course assays with cell recovery after drug withdrawal, demonstrated marked cytotoxicity following exposure to IST-FS 29 for 8, 24 and 72 h. Cultures treated for 8 h were able to partially re-grow by 144 h; on the contrary, longer times of exposure did not allow surviving cells to recover from the damage and actively proliferate. Cell morphology of cultures exposed to IST-FS 29 was assessed by inverted light microscopy after 24 and 72 h and was more consistent with cell death by necrosis which included cell size reduction, vacuolation of cytoplasm, round dying cells. The present results and our previous data, in vitro and in vivo, indicate the relevant cytotoxic activity of this organo-tin compound and suggest that IST-FS 29 might be a promising novel agent to be developed for the treatment of malignant brain neoplasms.

Spiro[1,2,4-benzotriazine-3(4H),4'-(1'-substituted)piperidines] and related compounds as ligands for sigma receptors

As analogues of some conformationally restricted spiropiperidine derivatives which are endowed with high affinity for sigma1 receptor, a set of 16 spiro[1,2,4-benzotriazine-3(4H),4'-(1'-substituted)piperidines] and congeneric compounds was prepared and tested for affinity to sigma1 receptor subtype. All N-arylalkyl substituted derivatives exhibited high affinity for the relevant receptor, with Ki in the low nanomolar range. Affinity for sigma2 subtype (assayed only for a few representative compounds) was from one to three order of magnitude lower. Spiro[1,2,4-benzotriazine-3(4H),4'-(1'-benzyl)piperidine] (2), with a ratio Ki sigma2/Ki sigma1 = 7000 should represent the most selective sigma1 ligand so far described.

Antitumor activity of a new orally active organotin compound: a preliminary study in murine tumor models

The toxicity and antitumor activity of the novel organotin compound triethyltin(IV)lupinylsulfide hydrochloride (IST-FS 29), administered by the oral route, have been evaluated against three transplantable murine tumor models: P388 lymphocytic leukemia, B16F10 melanoma and 3LL Lewis lung carcinoma. Mild and reversible signs of acute toxicity such as behavioral symptoms, weight loss and histological alterations were mainly reported at the highest single dose of 28 mg/kg. Conversely, lower concentrations of compound ranging from 7 to 21 mg/kg did not result in major toxic effects, even after repeated dosing. The antitumor activity studies showed that fractionation dosing, rather than single bolus administration, over 1 week, might prove more active and better tolerated by allowing the achievement of the highest therapeutic total dose of IST-FS 29 (42 mg/kg). Indeed, repeated administrations of IST-FS 29 resulted in marked significant improvement of antitumor activity against B16F10 (50% of tumor volume inhibition, p = 0.0003) and, to a greater extent, 3LL (90% of tumor volume inhibition, p = 0.0001) tumors. These results indicate that IST-FS 29 might be a suitable candidate as an orally administrable anticancer drug and support its further development in human tumor xenografts.