CB1 and CB2 receptors in the bed nucleus of the stria terminalis differently modulate anxiety-like behaviors in rats.

The endocannabinoid system is implicated in anxiety, but the brain sites involved are not completely understood. The bed nucleus of the stria terminalis (BNST) has been related to anxiety and responses to aversive threats. Besides, endocannabinoid neurotransmission acting via CB1 receptors was identified in the BNST. However, the presence of CB2 receptors and the role of BNST endocannabinoid system in anxiety-like behaviors have never been reported. Therefore, this study investigated the presence of CB1 and CB2 receptors in the BNST and their role in anxiety-like behaviors. For this, gene expression of the endocannabinoid receptors was evaluated in samples from anterior and posterior BNST. Besides, behaviors were evaluated in the elevated plus-maze (EPM) in unstressed rats (trait anxiety-like behavior) and after exposure to restraint stress (restraint-evoked anxiety-like behavior) in rats treated with either the CB1 receptor antagonist AM251 or the CB2 receptor antagonist JTE907 into the anterior BNST. The presence of CB1 and CB2 receptors gene expression was identified in anterior and posterior divisions of the BNST. Bilateral microinjection of AM251 into the anterior BNST dose-dependently increased EPM open arms exploration in unstressed animals and inhibited the anxiety-like behavior in the EPM evoked by restraint. Conversely, intra-BNST microinjection of JTE907 decreased EPM open arms exploration in a dose-dependent manner and inhibited restraint-evoked behavioral changes in the EPM. Taken together, these results indicate that CB1 and CB2 receptors present in the BNST are involved in control of anxiety-like behaviors, and control by the latter is affected by previous stress experience.

Bronchodilators for hyperinflation in COPD associated with biomass smoke: clinical trial.

Introduction: The efficacy of long-acting bronchodilators for COPD associated with biomass (BE-COPD) has not been properly evaluated. Objective: To determine the acute effect of indacaterol (IND) 150 µg q.d and tiotropium (TIO) 18 µg q.d. on lung hyperinflation, walking distance (WD) and dyspnea during the six-minute walking test (6MWT) in moderate BE-COPD at 30, 60 and 240 mins post-drug administration. Design: Randomized, controlled, open-level, crossover noninferiority clinical trial. Forty-two women with BE-COPD were randomly assigned to a bronchodilator sequence: IND-TIO or vice versa. Results: There were statistically significant changes over time in inspiratory capacity (IC) (p<0.0001), FEV1 (p<0.0001) and FVC (p<0.0001) when IND was used. When TIO was administered, an increase over all time periods was observed only for FEV1 (p<0.0001) and FVC (p<0.0001), whereas for IC an increase was observed only at 30 mins and 24 hrs after TIO administration. We did not find clinically significant increases in WD and dyspnea after the administration of both bronchodilators. Conclusion: Both IND and TIO showed significant and fast onset improvement in hyperinflation. Therefore, either of them may be recommended as a first line of treatment for COPD associated with BE-COPD.

Cystic fibrosis transmembrane conductance regulator modulators: Present and future in cystic fibrosis treatment. A review. / Moduladores CFTR (cystic fibrosis transmembrane conductance regulator): presente y futuro en la terapia de fibrosis quística. Revisión.

Cystic fibrosis transmembrane conductance regulator (CFTR) modulators are the present and future of drug management for patients with cystic fibrosis. The objective of this article is to review this therapeutic option. Scientific articles were reviewed by searching the MedLine database, which is available through the Cystic Fibrosis Foundation's official website, from 2009 to 2018, in English. Twelve articles about the current status of research in CFTR modulators were selected without restrictions regarding the type of study. To date, the United States Food and Drug Administration has approved three modulators: ivacaftor, lumacaftor + ivacaftor, and tezacaftor + ivacaftor, while other 11 drugs are being studied in different investigation phases. CFTR modulator therapy is a developing reality aimed at the highest goal of personalized medicine and promises to improve the quality of life of cystic fibrosis patients.

Los moduladores cystic fibrosis transmembrane conductance regulator (CFTR) representan el presente y el futuro del manejo farmacológico para los pacientes con fibrosis quística. El objetivo de esta publicación es realizar una revisión de esta opción terapéutica. Se revisaron artículos científicos consultando las bases de datos MedLine, información disponible a través de la página oficial Cystic Fibrosis Foundation, desde 2009 hasta 2018, en el idioma inglés. Sin restricciones respecto al tipo de estudio, se seleccionaron 12 artículos que incluyeron información sobre el estado actual de la investigación sobre moduladores CFTR. Actualmente, están aprobados por la Food and Drug Administration tres moduladores: ivacaftor, lumacaftor + ivacaftor y tezacaftor + ivacaftor, y hay otros 11 en diferentes fases de estudio. La terapia con moduladores CFTR es una realidad en desarrollo que apunta al máximo objetivo de la medicina personalizada y que promete mejorar la calidad de vida de pacientes con fibrosis quística.

Effects of indacaterol versus tiotropium on exercise tolerance in patients with moderate COPD: a pilot randomized crossover study.

OBJECTIVE:: To compare a once-daily long-acting ß2 agonist (indacaterol 150 µg) with a once-daily long-acting anticholinergic (tiotropium 5 µg) in terms of their effects on exercise endurance (limit of tolerance, Tlim) in patients with moderate COPD. Secondary endpoints were their effects on lung hyperinflation, exercise-related dyspnea, and daily-life dyspnea. METHODS:: This was a randomized, single-blind, crossover pilot study involving 20 patients (mean age, 60.9 ± 10.0 years; mean FEV1, 69 ± 7% of predicted). Spirometric parameters, Transition Dyspnea Index scores, Tlim, and exertional dyspnea were compared after three weeks of each treatment (with a one-week washout period between treatments). RESULTS:: Nineteen patients completed the study (one having been excluded because of COPD exacerbation). Improvement in Tlim from baseline tended to be greater after treatment with tiotropium than after treatment with indacaterol (96 ± 163 s vs. 8 ± 82 s; p = 0.06). Tlim significantly improved from baseline after treatment with tiotropium (having increased from 396 ± 319 s to 493 ± 347 s; p = 0.010) but not after treatment with indacaterol (having increased from 393 ± 246 to 401 ± 254 s; p = 0.678). There were no differences between the two treatments regarding improvements in Borg dyspnea scores and lung hyperinflation at "isotime" and peak exercise. There were also no significant differences between treatments regarding Transition Dyspnea Index scores (1.5 ± 2.1 vs. 0.9 ± 2.3; p = 0.39). CONCLUSIONS:: In patients with moderate COPD, tiotropium tends to improve Tlim in comparison with indacaterol. No significant differences were observed between the two treatments regarding their effects on lung hyperinflation, exercise-related dyspnea, and daily-life dyspnea. Future studies, including a larger number of patients, are required in order to confirm our findings and explore mechanistic explanations. (ClinicalTrials.gov identifier: NCT01693003 [http://www.clinicaltrials.gov/]). OBJETIVO:: Comparar um ß2-agonista de longa duração administrado uma vez por dia (indacaterol 150 µg) a um anticolinérgico de longa duração administrado uma vez por dia (tiotrópio 5 µg) quanto a seus efeitos na resistência ao exercício (limite de tolerância, Tlim) em pacientes com DPOC moderada. Os desfechos secundários foram seus efeitos na hiperinsuflação pulmonar, na dispneia causada pelo exercício e na dispneia na vida diária. MÉTODOS:: Estudo piloto randomizado cruzado e simples cego com 20 pacientes (média de idade: 60,9 ± 10,0 anos; média do VEF1: 69 ± 7% do previsto). Parâmetros espirométricos, pontuação no Transition Dyspnea Index, Tlim e dispneia aos esforços foram comparados após três semanas de cada tratamento (com uma semana de intervalo entre os tratamentos). RESULTADOS:: Dezenove pacientes completaram o estudo - um foi excluído por causa de exacerbação da DPOC. A melhora no Tlim tendeu a ser maior com tiotrópio do que com indacaterol (96 ± 163 s vs. 8 ± 82 s; p = 0,06). Em comparação com os valores basais, o Tlim melhorou significativamente com tiotrópio (aumentando de 396 ± 319 s para 493 ± 347 s; p = 0,010), mas não com indacaterol (aumentando de 393 ± 246 para 401 ± 254 s; p = 0,678). Não houve diferença entre os tratamentos quanto à melhora na pontuação na escala de dispneia de Borg e na insuflação pulmonar no "isotempo" e no pico do exercício. Também não houve diferenças significativas entre os tratamentos quanto à pontuação no Transition Dyspnea Index (1,5 ± 2,1 vs. 0,9 ± 2,3; p = 0,39). CONCLUSÕES:: Em pacientes com DPOC moderada, o tiotrópio tende a melhorar o Tlim em comparação com o indacaterol. Não houve diferenças significativas entre os tratamentos quanto a seus efeitos na insuflação pulmonar, na dispneia durante o exercício e na dispneia na vida diária. São necessários mais estudos, com um número maior de pacientes, para confirmar nossos achados e explorar explicações mecanicistas. (ClinicalTrials.gov identifier: NCT01693003 [http://www.clinicaltrials.gov/]).

Effects of indacaterol versus tiotropium on exercise tolerance in patients with moderate COPD: a pilot randomized crossover study / Efeitos do indacaterol versus tiotrópio na tolerância ao exercício em pacientes com DPOC moderada: estudo cruzado randomizado piloto

Abstract Objective: To compare a once-daily long-acting β2 agonist (indacaterol 150 µg) with a once-daily long-acting anticholinergic (tiotropium 5 µg) in terms of their effects on exercise endurance (limit of tolerance, Tlim) in patients with moderate COPD. Secondary endpoints were their effects on lung hyperinflation, exercise-related dyspnea, and daily-life dyspnea. Methods: This was a randomized, single-blind, crossover pilot study involving 20 patients (mean age, 60.9 ± 10.0 years; mean FEV1, 69 ± 7% of predicted). Spirometric parameters, Transition Dyspnea Index scores, Tlim, and exertional dyspnea were compared after three weeks of each treatment (with a one-week washout period between treatments). Results: Nineteen patients completed the study (one having been excluded because of COPD exacerbation). Improvement in Tlim from baseline tended to be greater after treatment with tiotropium than after treatment with indacaterol (96 ± 163 s vs. 8 ± 82 s; p = 0.06). Tlim significantly improved from baseline after treatment with tiotropium (having increased from 396 ± 319 s to 493 ± 347 s; p = 0.010) but not after treatment with indacaterol (having increased from 393 ± 246 to 401 ± 254 s; p = 0.678). There were no differences between the two treatments regarding improvements in Borg dyspnea scores and lung hyperinflation at "isotime" and peak exercise. There were also no significant differences between treatments regarding Transition Dyspnea Index scores (1.5 ± 2.1 vs. 0.9 ± 2.3; p = 0.39). Conclusions: In patients with moderate COPD, tiotropium tends to improve Tlim in comparison with indacaterol. No significant differences were observed between the two treatments regarding their effects on lung hyperinflation, exercise-related dyspnea, and daily-life dyspnea. Future studies, including a larger number of patients, are required in order to confirm our findings and explore mechanistic explanations. (ClinicalTrials.gov identifier: ...

RESUMO Objetivo: Comparar um β2-agonista de longa duração administrado uma vez por dia (indacaterol 150 µg) a um anticolinérgico de longa duração administrado uma vez por dia (tiotrópio 5 µg) quanto a seus efeitos na resistência ao exercício (limite de tolerância, Tlim) em pacientes com DPOC moderada. Os desfechos secundários foram seus efeitos na hiperinsuflação pulmonar, na dispneia causada pelo exercício e na dispneia na vida diária. Métodos: Estudo piloto randomizado cruzado e simples cego com 20 pacientes (média de idade: 60,9 ± 10,0 anos; média do VEF1: 69 ± 7% do previsto). Parâmetros espirométricos, pontuação no Transition Dyspnea Index, Tlim e dispneia aos esforços foram comparados após três semanas de cada tratamento (com uma semana de intervalo entre os tratamentos). Resultados: Dezenove pacientes completaram o estudo - um foi excluído por causa de exacerbação da DPOC. A melhora no Tlim tendeu a ser maior com tiotrópio do que com indacaterol (96 ± 163 s vs. 8 ± 82 s; p = 0,06). Em comparação com os valores basais, o Tlim melhorou significativamente com tiotrópio (aumentando de 396 ± 319 s para 493 ± 347 s; p = 0,010), mas não com indacaterol (aumentando de 393 ± 246 para 401 ± 254 s; p = 0,678). Não houve diferença entre os tratamentos quanto à melhora na pontuação na escala de dispneia de Borg e na insuflação pulmonar no "isotempo" e no pico do exercício. Também não houve diferenças significativas entre os tratamentos quanto à pontuação no Transition Dyspnea Index (1,5 ± 2,1 vs. 0,9 ± 2,3; p = 0,39). Conclusões: Em pacientes com DPOC moderada, o tiotrópio tende a melhorar o Tlim em comparação com o indacaterol. Não houve diferenças significativas entre os tratamentos quanto a seus efeitos na insuflação pulmonar, na dispneia durante o exercício e na dispneia na vida diária. São necessários mais estudos, com um número maior de pacientes, para confirmar nossos achados e explorar explicações mecanicistas. (ClinicalTrials.gov ...

The antipsychotic aripiprazole selectively prevents the stimulant and rewarding effects of morphine in mice.

Aripiprazole is an antipsychotic that acts as a partial agonist at dopamine D2 receptors, with a favorable pharmacological profile. Due to its unique mechanism of action, this compound has potential application as a substitutive therapy for drug addiction. Considering that distinct neural systems subserve the addictive and analgesic actions of opioids, we tested the hypothesis that aripiprazole selectively inhibit the abuse-related, but not the antinociceptive, effects of morphine. The drugs were tested in male Swiss mice for their effects on locomotion, conditioned place preference (CPP) and nociception. Morphine (20mg/kg) increased motor activity, whereas aripiprazole (0.1, 1 and 10mg/kg) did not induce any change. This antipsychotic, however, prevented morphine-induced locomotion. In the conditioning box, aripiprazole did not induce either reward or aversion. Yet, it prevented both the acquisition and the expression of morphine-induced CPP. Finally, none of the doses of this antipsychotic interfere with morphine (5mg/kg)-induced antinociception in the tail-flick test. In conclusion, aripiprazole inhibited the abuse-related effects of morphine at doses that do not interfere with basal locomotion, reward or aversion. Also, it did not alter morphine-induced antinociceptive effects. This antipsychotic should be further investigated as a possible substitutive strategy for treating certain aspects of opioid addiction.

Meta-analysis on the efficacy and tolerability of the augmentation of antidepressants with atypical antipsychotics in patients with major depressive disorder

We assessed the efficacy and tolerability of the augmentation of antidepressants (ATDs) with atypical antipsychotics (AAPs) to treat patients with major depressive disorder. A retrograde study to identify relevant patient data included databases of PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and Database of Abstracts of Reviews of Effects. Data from 17 trials, involving 3807 participants, were identified. The remission rate (RR) and overall response rate (ORR) of adjunctive treatment with AAPs were significantly higher than placebo treatment: RR=1.90 (95%CI=1.61-2.23, z=7.74, P<0.00001) and ORR=1.68 (95%CI=1.45-1.94, z=7.07, P<0.00001). We found that the short-term (4 weeks) treatment [ORR=1.70 (95%CI=0.98-2.95, Z=1.89, P=0.06)] was significantly different from the long-term (6-12 weeks) treatment [ORR=1.68 (95%CI=1.45-1.94, z=7.07, P<0.00001)]. No significant difference in ORR was observed between groups with or without sedative drugs. The discontinuation rate due to adverse effects was higher for adjunctive treatment with AAPs: ORR=3.32 (95%CI=2.35-4.70, z=6.78, P<0.00001). These results demonstrate that the augmentation of ATDs with AAPs (olanzapine, quetiapine, aripiprazole, and risperidone) was more effective than a placebo in improving response and remission rates, although associated with a higher discontinuation rate due to adverse effects.

Meta-analysis on the efficacy and tolerability of the augmentation of antidepressants with atypical antipsychotics in patients with major depressive disorder.

We assessed the efficacy and tolerability of the augmentation of antidepressants (ATDs) with atypical antipsychotics (AAPs) to treat patients with major depressive disorder. A retrograde study to identify relevant patient data included databases of PubMed, EMBASE, Cochrane Central Register of Controlled Trials, and Database of Abstracts of Reviews of Effects. Data from 17 trials, involving 3807 participants, were identified. The remission rate (RR) and overall response rate (ORR) of adjunctive treatment with AAPs were significantly higher than placebo treatment: RR=1.90 (95%CI=1.61-2.23, z=7.74, P<0.00001) and ORR=1.68 (95%CI=1.45-1.94, z=7.07, P<0.00001). We found that the short-term (4 weeks) treatment [ORR=1.70 (95%CI=0.98-2.95, Z=1.89, P=0.06)] was significantly different from the long-term (6-12 weeks) treatment [ORR=1.68 (95%CI=1.45-1.94, z=7.07, P<0.00001)]. No significant difference in ORR was observed between groups with or without sedative drugs. The discontinuation rate due to adverse effects was higher for adjunctive treatment with AAPs: ORR=3.32 (95%CI=2.35-4.70, z=6.78, P<0.00001). These results demonstrate that the augmentation of ATDs with AAPs (olanzapine, quetiapine, aripiprazole, and risperidone) was more effective than a placebo in improving response and remission rates, although associated with a higher discontinuation rate due to adverse effects.

Selective action of an atypical neuroleptic on the mechanisms related to the development of cocaine addiction: a pre-clinical behavioural study.

An increased function in the mesolimbic dopaminergic system has been extensively associated with the rewarding effects of both natural stimuli and drugs of abuse. Thus, dopamine receptor blockers, such as neuroleptic drugs, can be proposed as candidates for potential therapeutic approaches to treat drug dependence. Notwithstanding, this therapeutic potential of neuroleptics critically depends on a selective action on the specific mechanisms related to the development of addiction. We compared the effects of different doses of haloperidol, ziprasidone and aripiprazole (first-, second- and third-generation neuroleptics, respectively) on spontaneous locomotor activity of mice in a novel environment, hyperlocomotion induced by acute cocaine administration and cocaine-induced locomotor sensitization by a two-injection protocol. Whereas high doses of haloperidol abolished the three behavioural paradigms without selectivity, low doses of ziprasidone selectively abolished the development of the behavioural sensitization phenomenon. Finally, low doses of aripiprazole inhibited acute cocaine-induced hyperlocomotion and behavioural sensitization without modifying spontaneous locomotor activity. Thus, aripiprazole at lower doses was the most selective antipsychotic drug concerning the inhibition of the development of behavioural sensitization to cocaine. Because locomotor sensitization in rodents has been proposed to share plastic mechanisms with drug addiction in humans, our data provide relevant suggestions to the clinical practice.

Efficacy evaluation of some antibiotics against syrian brucella spp isolates, in vitro

Brucellosis is an endemic zoonosis in Syria, affecting large numbers of animals and there are an increasing number of cases in humans. The aim of this study is to investigate the in vitro efficacy of various traditional and new antibiotics against89 Brucella isolates (isolated from domestic animals) collected from different Syrian regions. Minimum inhibitory concentrations (MICs) of seventeen antibiotics were determined. Ciprofloxacin and ofloxacin were the most effective antibiotics, whereas sparfloxacin, levofloxacin, doxycycline and tetracycline had a moderate activity. In contrast, moxifloxacin and rifampicin had a low activity, while streptomycin, spiramycin and cephalosporines were ineffective. As a result, we come to the conclusion that a combination between one effective quinolone and doxycycline has a good efficacy against Brucella. Further in vivo studies are necessary to support this suggestion.(AU)

Carriage of antibiotic-resistant Escherichia coli among healthy children and home-raised chickens: a household study in a resource-limited setting.

We have previously observed high rates of acquired antibiotic resistance in commensal Escherichia coli from healthy children living in urban areas of Bolivia and Peru, including resistance to tetracycline and quinolones, which are not routinely used in childhood. In this work we investigated acquired resistance in commensal E. coli from healthy children and home-raised chickens in 12 households from one of the previously surveyed urban area in Bolivia, to ascertain the possibility of human-animal exchange of resistant strains in similar settings. The resistance rates to ampicillin, tetracycline, chloramphenicol, streptomycin, and trimethoprim-sulphametoxazole were overall high (≥50%) and comparable between children and chickens, whereas those to quinolones were significantly higher in chickens (81% vs. 29% for nalidixic acid; 43% vs. 10% for ciprofloxacin). Molecular characterization of tetracycline- and quinolone-resistant isolates (n = 66) from children and chickens of three selected households revealed a remarkable clonal diversity and, in some cases, the presence of the same resistant strains among children or among chickens living in the same household, but not between children and chickens. Several resistance plasmids were characterized, but inter-clonal plasmid dissemination was not detected. Overall, the results from the present study suggested that cross-transmission between children and home-raised chickens could not represent a major spreading mechanism for resistant E. coli in households of resource-limited settings with high human-animal promiscuity.

Aripiprazole for patients with schizophrenia and schizoaffective disorder: an open-label, randomized, study versus haloperidol.

INTRODUCTION: Aripiprazole, a dopamine D2 receptor partial agonist, has also partial agonist activity at serotonin (5-HT)1A receptors and antagonist activity at 5-HT2A receptors. METHODS: In this 8-week, multicenter, randomized, parallel-group, open-label, flexible-dose study, patients diagnosed with schizophrenia or schizoaffective disorder were randomized to aripiprazole 15-30 mg/day or haloperidol 10-15 mg/day. RESULTS: Patients treated with both aripiprazole and haloperidol improved from baseline in Positive and Negative Syndrome Scale total, positive, and negative scores as well as in Clinical Global Impressions scores (all P<.001). At the end of the study, the percentage of patients classified as responders--according to >or=40% reduction in the Positive and Negative Syndrome Scale negative subscale score--was significantly higher in the aripiprazole group (20%) than in the haloperidol group (0%) (P<.05). Additionally, a higher number of patients receiving haloperidol required more anticholinergic medications (P<.001) than aripiprazole-treated patients, whereas more aripiprazole (45.5%) than haloperidol-treated patients (12.9%) required benzodiazepines (P=.002). At endpoint, rates of preference of medication were higher in the aripiprazole group (63.2%) than in the haloperidol group (21.7%), as expressed by patients and caregivers (P=.001). CONCLUSION: Aripiprazole and haloperidol had similar efficacy in terms of reduction of overall psychopathology. Although aripiprazole has been demonstrated to be superior concerning negative symptoms and in terms of tolerability (extrapyramidal symptoms) and preferred by patients and caregivers than haloperidol, significantly more aripiprazole-treated patients required benzodiazepines.

Pharmacokinetic behavior and pharmacokinetic/pharmacodynamic integration of marbofloxacin after subcutaneous administration in goats.

The pharmacokinetic behavior of marbofloxacin was studied in goats after single-dose subcutaneous (SC) administration of 2mg/kg bodyweight. Drug concentration in plasma was determined by high performance liquid chromatography and the data obtained were subjected to non-compartmental kinetic analysis. Marbofloxacin peak plasma concentration (C(max)=1.77+/-0.24microg/mL) was reached 1.25+/-0.50h (T(max)) after SC administration. The elimination half-life (t(1/2beta)) and area under curve (AUC) were 5.74+/-1.21h and 8.15 vs 2.33microg h/mL, respectively. Taking into account the values obtained for the efficacy indices, it was concluded that a SC dose of 2mg/kg/24h of marbofloxacin could be adequate to treat infections caused by high susceptible bacteria like Escherichia coli or Salmonella spp.

Experimental pleurodesis induced by antibiotics (macrolides or quinolones).

PURPOSE: Chemical pleurodesis is a therapeutic tool for the treatment of recurrent pleural effusions, mainly those of neoplastic etiology. In the past, tetracycline was the sclerosant agent of choice in clinical practice, but presently, there is no consensus about an ideal agent. The aim of this study was to evaluate the effectiveness of macrolides (azithromycin and clarithromycin) or quinolones (levofloxacin and gatifloxacin) in inducing experimental pleurodesis in rabbits. METHOD: Forty New Zealand rabbits randomized into groups of 10 received (at a total volume of 2 mL for each animal) 1 of the 4 drugs by intrapleural injection. After 28 days, the animals were euthanized and the pleural cavity was evaluated macroscopically and microscopically. RESULTS: The intensity of the macroscopic adhesions was mild in all groups. On microscopic analysis, minimal pleural fibrosis and inflammation were observed in all animals. CONCLUSION: The macrolides (azithromycin or clarithromycin) and the quinolones (levofloxacin or gatifloxacin) when injected into the normal pleural space of rabbits are not effective in promoting pleurodesis. Additional research is required to identify sclerosing agents capable of inducing pleurodesis.

Determination of lomefloxacin in tablet preparations by liquid chromatography.

A sensitive, precise, and specific high-performance liquid chromatography (HPLC) method was developed for the assay of lomefloxacin (LFLX) in raw material and tablet preparations. The method validation parameters yielded good results and included the range, linearity, precision, accuracy, specificity, and recovery. It was also found that the excipients in the commercial tablet preparation did not interfere with the assay. The HPLC separation was performed on a reversed-phase Phenomenex C18 column (150 x 4.6 mm id, 5 microm particle size) with a mobile phase composed of 1% acetic acid-acetonitrile-methanol (70 + 15 + 15, v/v/v), pumped isocratically at a flow rate of 1.0 mL/min. The effluent was monitored at 280 nm. The calibration graph for LFLX was linear from 2.0 to 7.0 mg/mL. The interday and intraday precisions (relative standard deviation) were less than 1.0%. The method was applied for the quality control of commercial LFLX tablets to quantitate the drug.

Experimental pleurodesis induced by antibiotics (macrolides or quinolones) / Pleurodese experimental induzida por antibióticos (macrolídeos e quinolonas)

PURPOSE: Chemical pleurodesis is a therapeutic tool for the treatment of recurrent pleural effusions, mainly those of neoplastic etiology. In the past, tetracycline was the sclerosant agent of choice in clinical practice, but presently, there is no consensus about an ideal agent. The aim of this study was to evaluate the effectiveness of macrolides (azithromycin and clarithromycin) or quinolones (levofloxacin and gatifloxacin) in inducing experimental pleurodesis in rabbits. METHOD: Forty New Zealand rabbits randomized into groups of 10 received (at a total volume of 2 mL for each animal) 1 of the 4 drugs by intrapleural injection. After 28 days, the animals were euthanized and the pleural cavity was evaluated macroscopically and microscopically. RESULTS: The intensity of the macroscopic adhesions was mild in all groups. On microscopic analysis, minimal pleural fibrosis and inflammation were observed in all animals. CONCLUSION: The macrolides (azithromycin or clarithromycin) and the quinolones (levofloxacin or gatifloxacin) when injected into the normal pleural space of rabbits are not effective in promoting pleurodesis. Additional research is required to identify sclerosing agents capable of inducing pleurodesis.

OBJETIVO: A pleurodese química representa uma ferramenta terapêutica utilizada no tratamento dos processos pleurais recidivantes, principalmente nos derrames neoplásicos. A escolha do melhor esclerosante pleural é ainda motivo de controvérsia, não havendo consenso com relação ao agente considerado ideal. O objetivo deste estudo é avaliar a efetividade dos macrolídeos (azitromicina e claritromicina) e das quinolonas (levofloxacina e gatifloxacina) na indução de pleurodese experimental em coelhos. MÉTODOS: Quarenta animais randomizados em grupos de 10, receberam, em volume total de 2 mL, estas drogas através de injeção intrapleural. RESULTADOS: Após 28 dias, os animais foram sacrificados sendo avaliada a cavidade pleural. A intensidade das aderências macroscópicas assim como da fibrose e da inflamação observadas à microscopia foi discreta tanto no grupo que recebeu macrolídeos quanto naquele que recebeu quinolonas. CONCLUSÃO: Azitromicina, Claritromicina, Levofloxacina e Gatifloxacina quando injetados na cavidade pleural de coelhos, não são eficazes na indução de pleurodese. Novas pesquisas devem ser realizadas com o intuito de identificar agentes esclerosantes capazes de produzir sínfise pleural.

Pharmacokinetics of marbofloxacin after single intravenous and repeat oral administration to cats.

The pharmacokinetic properties of marbofloxacin, a third generation fluoroquinolone, were investigated in six cats after single intravenous (IV) and repeat oral (PO) administration at a daily dose of 2 mg/kg. Marbofloxacin serum concentration was analysed by microbiological assay using Klebsiella pneumoniae ATCC 10031 as micro-organism test. Serum marbofloxacin disposition was best described by bicompartmental and mono-compartmental open models with first-order elimination after IV and oral dosing respectively. After IV administration, distribution was rapid (T(1/2(d)) 0.23+/-0.24 h) and wide, as reflected by the steady-state volume of distribution of 1.01+/-0.15 L/kg. Elimination from the body was slow with a body clearance of 0.09+/-0.02 L/h kg and a T(1/2) of 7.98+/-0.57 h. After repeat oral administration, absorption half-life was 0.86+/-1.59 h and T(max) of 1.94+/-2.11 h. Bioavailability was almost complete (99+/-29%) with a peak plasma concentration at the steady-state of 1.97+/-0.61 mug/mL. Drug accumulation was not significant after six oral administrations. Calculation of efficacy predictors showed that marbofloxacin has good therapeutic profile against Gram-negative and Gram-positive bacteria with a MIC(50) value <0.25 microg/mL.

Age-related changes in the pharmacokinetics of marbofloxacin after intravenous administration in goats.

The pharmacokinetics of marbofloxacin was studied in adult goats and 1-, 3- and 6-weeks-old kids after single dose i.v. dose of 2 mg/kg body weight. Drug concentration in plasma was determined by high-performance liquid chromatography (HPLC) and the data collected were subjected to compartmental kinetic analysis. Volume of distribution was relatively high in adult goats (Vss = 1.31 L/kg), and increased with age (Vss = 0.92 L/kg, 0.95 L/kg and 1.00 L/kg, in 1-, 3- and 6-weeks-old kids respectively). Total body clearance (Cl) also increased with age from 0.080 L/kg.h (1-week-old) to 0.097 L/kg.h (3-weeks-old), 0.18 L/kg.h (6-weeks-old) and 0.23 L/kg.h (adult goats). As a consequence of increased body Cl, area under the plasma concentration vs. time curve decreased with age (AUC = 27.46 microg.h/mL, 22.61 microg.h/mL, 11.86 microg.h/mL and 8.44 microg.h/mL in 1-, 3-, 6-weeks-old kids and adults, respectively) and a longer elimination half-life was found during the first 3 weeks of age (t1/2beta = 9.66 h, 8.25 h, 6.44 h and 7.18 h, in 1-, 3-, 6-weeks-old kids and adults, respectively). Mean residence time decreased with age from 11.86 h in 1-week-old kids to 9.63 h (3 weeks), 5.76 h (6 weeks) and 5.06 h in adult goats.