The enzyme inducers 3-methylcholanthrene and phenobarbital affect the activities of glucocorticoid hormone-regulated enzymes in rat liver and kidney

3-Methylcholanthrene, an inducer of P448-type cytochromes (mostly 1A1 and 1A2), and phenobarbital, an inducer of P450-type cytochromes (mostly 2B1 and 2B2), are prototypical for the actions of many xenobiotics. They cause endocrine disruption by affecting, among others, steroid hormone levels. Rats were treated with single bolus doses of 3-methylcholanthrene or phenobarbital, and enzyme activities that are controlled by glucocorticoids were measured in liver and kidney. The activities of the cytosolic enzymes L-alanine aminotransferase, indoleamine 2,3-dioxygenase (L-tryptophan pyrrolase), phosphoenolpyruvate carboxykinase, L-serine dehydratase and L-tyrosine aminotransferase were affected in a similar fashion: an initial activity reduction followed by two overshoots of activity 1 and 2 days after dosing. 3-Hydroxy-3-methylglutaryl coenzyme A reductase, the microsomal key enzyme of sterol synthesis, responded with a temporary reduction of activity only and evidently lost its diurnal rhythm. The time course of these changes is most likely caused by a combination of sub-physiological levels of glucocorticoids plus changes of other regulatory hormones elicited by feed intake, postprandial state, etc. A possible role for a combined action of the arylhydrocarbon (Ah) and glucocorticoid receptors in the effects of 3-methylcholanthrene is also suggested.

Advanced HIV infection treated with zidovudine monotherapy: lifetime values of absolute cost-effectiveness as a pharmacoeconomic reference for future studies evaluating antiretroviral combination treatments. The Osservatorio SIFO sui Farmaci

OBJECTIVE

This study was undertaken to evaluate the cost and the effectiveness of zidovudine monotherapy in patients with advanced HIV infection and to derive preliminary data on the cost-effectiveness of the triple treatment with saquinavir plus zalcitabine plus zidovudine compared with zidovudine alone.

DESIGN

We used a combined method of survival analysis utilizing both the quality-adjusted time without symptoms or toxicity (Q-TWIST) method and the Gompertz approach. This combined method was applied to assess the absolute cost-effectiveness and cost-utility ratios of zidovudine monotherapy and to perform a preliminary incremental cost-effectiveness comparison of saquinavir plus zalcitabine plus zidovudine versus zidovudine alone. The clinical material used in our study was derived from two reports on the treatment of advanced HIV infection. Data of lifetime costs of HIV infection were obtained from published information.

RESULTS

In patients with advanced HIV infection treated with zidovudine monotherapy, lifetime survival was 252.1 discounted person-years per 100 patients. Using an average lifetime cost of $93,000 (discounted) per individual, the absolute ratio of cost-effectiveness for zidovudine monotherapy was $36,980 per life-year, while the absolute cost-utility ratio was $47,112 per quality-adjusted life-year. In the comparative analysis of saquinavir plus zalcitabine plus zidovudine versus zidovudine alone, our calculations showed that the administration of the triple treatment can have an "average" cost-effectiveness, provided that mean lifetime survival per patient (discounted) is improved to at least 3.68 years (with an average survival gain of at least 14 mo per patient).

CONCLUSIONS

The values of absolute cost-effectiveness and cost-utility ratios for zidovudine monotherapy are a useful reference point for further pharmacoeconomic studies in the area of antiretroviral drugs.

Structure-activity relationships in quinoline Reissert derivatives with HIV-1 reverse transcriptase inhibitory activity

The relationship between the chemical structure and the HIV-1 RT inhibitory activity has been studied for a series of quinoline derivatives. Two methods were used: a standard QSAR analysis, by combining the methods of Hansch and Free-Wilson, and an analysis using quantum chemistry indices as descriptor parameters, by the semiempirical method AM1. The equations obtained lead to the proposal that the activity of the compounds increases, mainly, with the presence of electron-withdrawing substituents in position 6 of the quinoline ring that cause a decrease in the energy from the molecular orbital LUMO. In turn, this fact leads to the proposal that the most important interaction of these compounds with the HIV-1 RT is a charge transfer type interaction, with the quinoline aromatic ring acting as acceptor.

Synthesis and evaluation of new Reissert analogs as HIV-1 RT inhibitors. 2. Benzo[f]quinoline and pyridine derivatives

The synthesis and preliminary evaluation of new benzo[f]quinoline and pyridine derivatives, obtained by application of the Reissert method and its modifications, as HIV-1 RT inhibitors and anti-infectives are presented. The most active products against HIV-1 RT wild type are the ethyl 2-cyano-1,2-dihydrobenzo[f]quinoline-1-carboxylate 2b, propyl 2-cyano-1,2-dihydrobenzo[f]quinoline-1-carboxylate 2c, and 2-cyano-1-(2'-furoyl)-1,2-dihydrobenzo[f]quinoline 2n, which maintain their activity against the mutant type P236L, resulting inactive against the Y181C type. Using the data previously obtained by our research team for analogous series derived from quinoline as reference, the compounds which have now been obtained present an increase in the cytotoxic character attributable to the introduction of a benzene ring fused with the quinoline base nucleus, as well as a decrease of the activity as HIV-1 RT inhibitors when the quinoline benzenic ring is eliminated.

Synthesis and evaluation of new Reissert analogs as HIV-1 reverse transcriptase inhibitors. 1. Quinoline and quinoxaline derivatives

The synthesis and preliminary evaluation of new quinoline and quinoxaline derivatives (obtained by applying the original Reissert method, conveniently modified) as HIV-1 Reverse Transcriptase (RT) inhibitors are presented in this paper; likewise, the first structure-activity relationships are also proposed. Propyl 2-cyano-1(2H)-quinolin-carboxylate 2e, isopropyl 2-cyano-1 (2H)-quinolincarboxylate 2f, butyl 2-cyano-1 (2H)-quinolincarboxylate 2g and isobutyl 2-cyano-1 (2H)-quinolincarboxylate 2h have been selected as lead compounds. These compounds are active against the HIV-1 RT mutant type P236L (2f, IC50 = 1.2 microM) and present activity as anti-infective agents in HLT41acZ-1IIIB cells, showing no cytotoxicity at the active concentrations.

New indole and pyridazinoindole analogs--synthesis and study as inhibitors of phosphodiesterases and as inhibitors of blood platelet aggregation

This paper presents the synthesis of new indole, pyridazino[4,5-b]-indole, and pyridazino[4,5-a]indole analogs as well as a study of their "in vitro" activity as inhibitors of different phosphodiesterases isolated from dog cardiac tissue, dog aorta, and bovine platelets; the study of their activity as inhibitors of platelet aggregation in guinea pig whole blood, with ADP and arachidonic acid (AA) as pro-aggregants, is also included. The selected compounds 8-benzyloxy-3,4-dihydro-1-(3,4,5-trimethoxy)benzylideneaminopyridazin o[4,5- b]indole 14g, and 8-benzyloxy-4-[(3,4-dimethyl)pyrazolyl]pyridazino[4,5-b]indo le 20 present an interesting profile as potential inodilators, with a complementary, beneficial activity as inhibitors of the aggregation, activities which could possibly be related to the inhibition of the PDE's. Among the other compounds studied, 8-benzyloxy-3,4-dihydro-1-[4-(methyl)piperazino]acetamidopyrida zino[4,5- b]indol-4-one 16c and 8-benzyloxy-3,4-dihydro-1-[4-(2- methoxyphenyl)piperazino]acetamidopyridazino[4,5-b]indol-4-o ne 16f stood out as inhibitors of platelet aggregation, with a mechanism that could possibly be related to the AA cascade.

Comparative analysis of Brucella serotype A and M and Yersinia enterocolitica O:9 polysaccharides for serological diagnosis of brucellosis in cattle, sheep, and goats

Hapten polysaccharides of Brucella smooth M and A serotypes were prepared from Brucella sp. and Yersinia enterocolitica O:9 by previously described hydrolytic (O chain) or nonhydrolytic (native hapten [NH]) procedures. The purified polysaccharides differed only in the presence (O chain) or absence (NH) of lipopolysaccharide core sugars. The polysaccharides were compared by reverse radial immunodiffusion for the diagnosis of brucellosis in cattle (Brucella abortus biotype 1 [A serotype] and Brucella melitensis biotype 3 [AM serotype]), sheep (B. melitensis biotypes 1 [M serotype] and 3), and goats (B. melitensis biotype 1). The reverse radial immunodiffusion test with the NH from B. melitensis 16 M (serotype M) showed the highest sensitivity (89.6 to 97.3%), regardless of the host species and the serotype of the infecting Brucella sp. Y. enterocolitica O:9 NH (A serotype) was useful for diagnosing disease in cattle infected with B. abortus biotype 1, but not in cattle infected with B. melitensis biotype 3, sheep, or goats. The different results obtained with the serotype M and A polysaccharides and the sera from animals infected with M, A, and AM serotypes of Brucella spp. showed that in naturally infected animals, a large proportion of the antibodies are directed to or react with a previously defined common epitope(s) (J. T. Douglas and D. A. Palmer, J. Clin. Microbiol. 26:1353-1356, 1988) different from the A or M epitopes. By using the radial immunodiffusion test with B. melitensis 16M NH, it was possible to differentiate infected from vaccinated cattle, sheep, and goats with a sensitivity and specificity similar to that of the complement fixation test.

New pyridazino[4,5-b]indole derivatives with inodilator and antiaggregatory activities

Some 4-(3,5-dimethylpyrazol) 5H-pyridazino [4,5-b]indoles (7), 1,2,4-triazolo [4,3-b]pyridazino [4,5-b]indoles (9) and 1,2,4-tetrazolo [4,5-b]pyridazino [4,5-b] indoles (11) substituted in position 1 by amino groups have been synthesized and tested as inotropic agents and inhibitors of platelet aggregation. 6-Imidazolyl-11H-1,2,4-triazolo [4,3-b]pyridazino [4,5-b]indole (9) shows an activity superior to that of amrinone, with a notable selectivity towards phosphodiesterase (PDE) IV and PDEV, vasodilator activity and a good effect on blood platelet aggregation.

New 4-amino-7,8-dimethoxy-5H-pyrimido[5,4-b]indole derivatives: synthesis and studies as inhibitors of phosphodiesterases

A series of 4-amino-7,8-dimethoxy-5H-pyrimido[5,4-b]indole derivatives has been synthesized. These compounds resemble carbazeram and other pyridazino compounds with activity in the cardiovascular system. Some of these new compounds possess inotropic activity (Table 2), with a complementary effect on the inhibition of different CGI-PDE (Table 3). The most active compounds 5, 6d, and 7 also possess activity as vasodilators (Table 4). Some of these new compounds inhibit blood platelet aggregation induced by ADP and AA and are active as inhibitors of human platelet PDEs (Tables 5 and 6).

A novel class of cardiotonic agents: synthesis and biological evaluation of pyridazino[4,5-b]indoles with cyclic AMP phosphodiesterases inhibiting properties

Some fused pyridazino[4,5-b]indoles (7) were synthesized. These new compounds present a planar topography and some resemblance to carbazeram, imadozan, and other pyridazino agents with cardiotonic activity. These compounds also possess a complementary effect as inhibitors of platelet aggregation. 6-(3,5-Dimethylpyrazolyl)-1,2,4-triazolo[4,3-b]pyridazino[4, 5-b]indole (7a) has a good profile as an inodilatador with antiaggregate activity due to the inhibition of phosphodiesterase.

Anthelmintic activity of pyrazinothiadiazine dioxide derivatives

In a search for new anthelmintic compounds, some pyrazinothiadiazine dioxide derivatives were synthesized. Their anthelmintic activity was tested against larva and preadult stages of Trichinella spiralis. The mode of action and acute toxicity of these compounds were investigated. Structure-activity relationships are discussed.

Pharmacological characterization of the vasodilator effect of DF-100, a new pyridazino[4,5-b]indole, in vascular smooth muscle

DF-100, i.e., 1-hydrazino-4-(3,5-dimethyl-1-pyrazolyl)-5H-pyridazino[4,5-b ]indole is a new pyridazino[4,5-b]indole derivative related to dihydralazine. The inhibitory effects of DF-100 were investigated on the contractions in isolated aorta and portal vein. In rat aorta, DF-100 inhibited both K(+)-induced as well as norepinephrine-induced contractions. DF-100 also caused dose-dependent relaxation of contractions produced by 80 mM K+. Moreover, DF-100 significantly inhibited the CaCl2 dose response in high-K+ depolarizing medium. DF-100 inhibited the phasic contractile response to norepinephrine and the caffeine-induced response, suggesting that this molecule affects the mobilization of Ca2+ from a membrane-bound pool. In rat portal vein, DF-100 inhibited the spontaneous rhythmic contractions. The results obtained in this study in isolated rat aorta and portal vein suggest that DF-100 has a direct vasodilating effect that could be attributed to inhibition of cellular Ca2+ influx and release from intracellular stores.

Antihypertensive and vasodilator effect of A-80b, a new pyridazino indole derivative

The hypotensive and antihypertensive activities of a A-80b, a newly synthesized pyridazino[4,5-b]indole derivate were investigated in anaesthetized rats. In vitro studies were also done to examine the possible mechanism of its vasodilator action. A 80b (3-15 mg/kg i.p.) showed potent and long-lasting antihypertensive activity in spontaneous hypertensive rats. In normotensive rats, A-80b (7.5-30 mg/kg i.p.) also lowered blood pressure but less than in hypertensive rats. The decrease in diastolic pressure was greater than the decrease in systolic pressure and cardiac frequency was not modified significantly. Contractile responses induced in isolated rat thoracic aorta by K+ and noradrenaline were inhibited by A-80b. In K(+)-depolarized rat aorta, A-80b showed dose-dependent inhibition of the Ca(2+)-induced contraction. Also, A-80b inhibited spontaneous contractions of rat portal vein. The vasodilator action seemed to be endothelium-independent. These results suggest that A-80b is a new chemical entity which exerts a hypotensive and antihypertensive effect, possibly attributable to vasodilator activity via interference with Ca2+ influx and probably Ca2+ mobilization from intracellular stores.

New indole and triazino[5,4-b]indol-4-one derivatives: synthesis and studies as inotropics and inhibitors of blood platelet aggregation

New triazino[5,4-b]indol-4-one derivatives carrying amino groups in position 3 were synthetized and tested as inotropic agents and inhibitors of platelet aggregation. 2h, 2p, 5p, and 6g are the most active as inotropic agents. Compounds were tested as inhibitors of platelet aggregation induced by adenosine 5'-diphosphate (ADP) and arachidonic acid (AA) (guinea pig whole blood). 2k, 2p, 5o, 6d, 6m, and 6o are the most active as inhibitors of the platelet aggregation induced by AA. 6d, 6h, and 6o are most active compounds also in the aggregation induced by ADP. Radioimmunoassay studies, following AA induced aggregation, measuring thromboxane B2 (TXB2) and prostaglandin E2 (PGE2) were carried out on compounds 2b, 2d, 2f, 2g, 2h, 2i, 2k, 2m, 2o, 2p, 2r, 5i, 5j, 5k, 5r, and 5f, which inhibit platelet aggregation induced by AA. None of the compounds tested turned out to be selective inhibitors. Compounds 2h and 2p showed both inotropic and platelet aggregation inhibiting activity.

New 5H-pyridazino[4,5-b]indole derivatives. Synthesis and studies as inhibitors of blood platelet aggregation and inotropics

Some fused 5H-pyridazino[4,5-b]indoles (7-10), substituted in positions 1 and 4 by hydrazine and/or amino groups, have been synthesized. These new compounds present a planar topography, a dipole with an adjacent acidic proton, and a basic hydrogen-acceptor site opposite the dipole. These compounds have some resemblance to carbazeram and other pyridazino agents with cardiotonic activity. Some of the new compounds here described possess inotropic activity (Table I and II), with a complementary effect as inhibitors of platelet aggregation (Table III and IV). 1-Hydrazino-4-(3,5-dimethyl)-1-pyrazolyl-5H-pyridazino[4,5-b ]indole hydrochloride (7a.HCl) is the first compound described in the literature with activities as inhibitor of PDE-IV and as selective inhibitor of TXA2 synthetase (Table V).

[Intrinsic PEEP as a ventilation complication after pneumonectomy]

We report the case of a female patient who developed a clinical picture characterized by hemodynamic deterioration, bradycardia and asystole due to pulmonary hyperinsufflation (documented by X-ray examination) during the immediate postoperative phase of a right pneumonectomy. Occlusion of the respiratory limb of the respirator was followed by a positive pressure at the end of the respiration (PEEP) suggesting the presence of an intrinsic PEEP independent of the respirator. Application of a PEEP to the respirator induced a radiologic improvement. The mechanisms by which an intrinsic PEEP may develop are discussed.

[Improving drug prescription in primary care: a controlled and randomized study of an educational method]

BACKGROUND

The aim of the present study was to assess whether educational intervention on the primary care physician may be an effective method to improve drug prescription.

METHODS

An experimental randomized controlled study was carried out in 244 physicians of the management area No. 5 of the Institut Català de la Salut. Intervention consisted in 3 individualized interviews with the 123 physicians of the study group (IG), during which written informative material was also presented. The issues were: cerebral and peripheral vasodilators (CPVD) and antibiotics. The changes in the prescription of CPVD, combination of anti-infective agents with expectorants, mucolytics and/or balsamics (R05C1) and cephalosporins were specially evaluated in both groups. Subsequently, a stratified analysis was carried out depending on the volume of prescription of the physicians.

RESULTS

The IG showed a greater reduction in the prescription of CPVD (9.78 bottles per physicians and months versus 6.43, p less than 0.01). The relative reduction in R05C1 prescription was also higher in the IG (12.3% versus 6.7%, p less than 0.01). The expenditure showed similar results. The use of oral cephalosporins increased in the IG and was reduced in the CG (p less than 0.01).

CONCLUSIONS

The results show a favorable impact of personalized information in the groups with high prescription volume, which is particularly remarkable in the highest prescribers.

Action of metadoxine on isolated human and rat alcohol and aldehyde dehydrogenases. Effect on enzymes in chronic ethanol-fed rats

Metadoxine (pyridoxine-pyrrolidone carboxylate) has been reported to accelerate ethanol metabolism. In the present work we have investigated the effect of metadoxine on the activities of isolated alcohol and aldehyde dehydrogenases from rat and man, and on the activity of these enzymes in chronic ethanol-fed rats. Our results indicate that in vitro metadoxine does not activate any of the enzymatic forms of alcohol dehydrogenase (classes I and II) or aldehyde dehydrogenase (low-Km and high-Km, cytosolic and mitochondrial). At concentrations higher than 0.1 mM, metadoxine inhibits rat class II alcohol dehydrogenase, although this would probably not affect the physiological ethanol metabolism. Chronic ethanol intake for 5 weeks results in a 25% decrease of rat hepatic alcohol dehydrogenase (class I) activity as compared with the pair-fed controls. The simultaneous treatment with metadoxine prevents activity loss, suggesting that the positive effect of metadoxine on ethanol metabolism can be explained by the maintenance of normal levels of alcohol dehydrogenase during chronic ethanol intake. No specific effect of chronic exposure to ethanol or to metadoxine was detected on rat aldehyde dehydrogenase activity.

[A quantitative study of the consumption of antihypertensives in Management Area 5 of the ICS (Costa de Ponent). Institut Català de la Salut]

The use of antihypertensive drugs (AHD) in the area n degrees 5 of the Institut Català de la Salut was evaluated for the period October 1986-December 1987. The unit of measure was the DDD (daily defined dose) per 1,000 population individuals per day. The overall use of AHD in 1987 was 49.31 DDDs/1,000 individuals/day; it was distributed among diuretics (53.5% of all AHD), beta-blockers (11.3%), and other AHD (35.2%). The most commonly prescribed drugs, by decreasing frequency order, were combinations of low ceiling diuretics with potassium sparing drugs, and of rauwolfia alkaloids with diuretics, followed by nifedipine, chlortalidone and furosemide. The interannual evaluation disclosed an increase of 18.6% in 1987 as compared with the preceding year, mostly at the expense of beta-blockers. On the other hand, there was a tendency to refrain from the use of fixed dose drug associations. This is a criterion of better use of antihypertensive therapy.

[Ki-1 non-Hodgkin's lymphoma. A multihospital study of 21 cases]

The Ki-1 monoclonal antibody recognizes a specific membrane antigen of activated lymphoid cells and stains large-cell non Hodgkin's lymphomas and Hodgkin's disease. Thus, it is widely used in the diagnosis of anaplastic lymphomas. Morphologically, the Ki-1 monoclonal non Hodgkin's lymphoma are diffuse of multifocal either classical or cell anaplastic type. The clinical behaviour is similar to the rest of the high grade lymphomas, disseminated at diagnosis but may reach remission after aggressive chemotherapy. The immunophenotype showed T, B or null nature of the latter. The clinical and pathological results of our study carried out in a group of 21 cases ki-1 positive lymphomas is herewith reported.

Selective thromboxane synthetase inhibitors and antihypertensive agents. New derivatives of 4-hydrazino-5H-pyridazino[4,5-b]indole, 4-hydrazinopyridazino[4,5-a]indole, and related compounds

A series of new derivatives of 4-hydrazino-5H-pyridazino[4,5-b]indole (5) and 4-hydrazinopyridazino[4,5-a]indole (12) have been synthesized to investigate their activities as selective thromboxane synthetase inhibitors as well as antihypertensive agents. Several of the prepared compounds were found to be selective thromboxane synthetase inhibitors, in concordance with the Gorman model. The most potent were 8-(benzyloxy)-3,4-dihydro-4-oxo-5H-pyridazino[4,5-b]indole (3c) and 8-methoxy-4-hydrazino-5H-pyridazino[4,5-b]indole (5). This last compound did not inhibit prostacyclin formation and showed an antihypertensive activity similar to that of hydralazine. The acute toxicity in mice for 5a . HCl is about 2.2 times less than that for hydralazine.