Genetic polymorphisms of the serotonin transporter are not related with depression in temporal lobe epilepsy caused by hippocampal sclerosis

BACKGROUND

Mood disorders are the most frequent psychiatric disorders in patients with temporal lobe epilepsy caused by hippocampal sclerosis (TLE-HS). The pathophysiological mechanisms in common between TLE and mood disorders include abnormalities in the serotonergic pathway. We aimed to evaluate the association between serotonin transporter genetic polymorphisms - 5-HTTLPR and 5-HTTVNTR - and the presence of mood disorders in patients with TLE-HS.

METHODS

We evaluated 119 patients with TLE-HS, with and without psychiatric disorder; 146 patients diagnosed with major depressive disorder (MDD), and 113 healthy volunteers. Individuals were genotyped for the 5-HTTLPR and 5-HTTVNTR polymorphisms.

RESULTS

No difference was observed between the TLE-HS groups, healthy controls, and MDD without epilepsy. There was a correlation between the 12-allele of the 5-HTTVNTR and the family history of patients with epilepsy with TLE-HS (p = 0.013).

CONCLUSIONS

In this study conducted in two Brazilian centers, the serotonin transporter polymorphisms evaluated cannot be associated with depressive disorder in patients with TLE-HS. Still, they do have some influence over some clinical characteristics of epilepsy in TLE-HS. These data may not be reproduced in other populations with distinct ethnic characteristics.

SIGMA-VB: Validity and reliability of the Brazilian Portuguese version of the Montgomery-Åsberg Depression Rating Scale using the Structured Interview Guide for the MADRS

Objective:

The Montgomery-Åsberg Depression Rating Scale (MADRS) is widely used to assess depression severity. The Structured Interview Guide for the MADRS (SIGMA) was created to standardize MADRS assessment. The objective of this study was to translate and validate the original SIGMA into a Brazilian Portuguese version (SIGMA-VB).

Methods:

We translated and cross-culturally validated the original SIGMA into the SIGMA-VB, and assessed its psychometric properties using data from 93 adult outpatients enrolled in the Integral Assessment in Unipolar Depression (AIUNI) trial. Participants were assessed by two raters on five visits over 8 weeks. We calculated multiple interrater reliability indexes for the SIGMA-VB and used the Hamilton Depression Hating Scale (HAM-D) for validation purposes.

Results:

According to the SIGMA-VB, participants had moderate depression at baseline followed by mild depression at 8 weeks. We found over 90% of correlation between scores attributed by different raters using the SIGMA-VB. Correlations between the SIGMA-VB and the HAM-D were above 66%.

Conclusion:

Our findings confirm that the SIGMA-VB is a valid and reliable instrument to assess depression severity in clinical research and practice. Its interrater reliability was similar to that of a previously published Japanese version of the SIGMA.

Double Blinded Randomized Trial of Subcutaneous Trigeminal Nerve Stimulation as Adjuvant Treatment for Major Unipolar Depressive Disorder

BACKGROUND

More than 30% of major depressive disorder patients fail to respond to adequate trials of medications and psychotherapy. While modern neuromodulation approaches (ie, vagal nerve stimulation, deep brain stimulation) are yet to prove their efficacy for such cases in large randomized controlled trials, trigeminal nerve stimulation (TNS) has emerged as an alternative with promising effects on mood disorders.

OBJECTIVE

To assess efficacy, safety, tolerability, and placebo effect duration of continuous subcutaneous TNS (sTNS) in treatment-resistant depression (TRD).

METHODS

The TREND study is a single-center, double-blind, randomized, controlled, phase II clinical trial. Twenty unipolar TRD patients will receive V1 sTNS as adjuvant to medical therapy and randomized to active vs sham stimulation throughout a 24-wk period. An additional 24-wk open-label phase will follow. Data concerning efficacy, placebo response, relapse, and side effects related to surgery or electrical stimulation will be recorded. We will use the HDRS-17, BDI-SR, IDS_SR30, and UKU scales.

EXPECTED OUTCOMES

The main outcome measure is improvement in depression scores using HAM-17 under continuous sTNS as adjuvant to antidepressants. Active stimulation is expected to significantly impact response and remission rates. Minor side effects are expected due to the surgical procedure and electrical stimulation. The open-label phase should further confirm efficacy and tolerability.

DISCUSSION

This study protocol is designed to define efficacy of a novel adjuvant therapy for TRD. We must strive to develop safe, reproducible, predictable, and well-tolerated neuromodulation approaches for TRD patients impaired to manage their lives and contribute with society.

Cognitive outcomes of TMS treatment in bipolar depression: Safety data from a randomized controlled trial

BACKGROUND

Bipolar depression (BD) is a highly prevalent condition associated with marked cognitive deficits that persist even in the euthymic phase of the illness. Pharmacological treatments for BD might further aggravate cognitive impairment, highlighting the need of developing interventions that present cognitive safety. In this study, we evaluated the cognitive effects of H1-coil (deep) transcranial magnetic stimulation (TMS) in patients with treatment-resistant bipolar depression.

METHODS

Fourty-three patients were randomized to receive 20 sessions of active (55 trains, 18 Hz, 120% resting motor threshold intensity) or sham rTMS within a double-blind, sham-controlled trial. A battery of 20 neuropsychological assessments, grouped in 6 domains (attention and processing speed, working memory and executive function, inhibitory control, language, immediate verbal memory, and long-term verbal memory) was performed at baseline and after 4 and 8 weeks of trial onset. Depressive symptoms were assessed with the 17-item Hamilton Rating Scale for Depression.

RESULTS

Cognitive improvement was shown for all cognitive domains. It occurred regardless of intervention group and depression improvement. For the language domain, greater improvement was observed in the sham group over time. No correlations between depression (at baseline or during treatment) and cognitive improvement were found.

LIMITATIONS

Absence of healthy control group.

CONCLUSION

The results of this exploratory study provide evidence on the cognitive safety of H1-coil TMS for BD patients. Putative pro-cognitive effects of rTMS in BD were not observed and thus should be further investigated.

Treatment of Bipolar Depression with Deep TMS: Results from a Double-Blind, Randomized, Parallel Group, Sham-Controlled Clinical Trial

Bipolar depression (BD) is a highly prevalent condition with limited therapeutic options. Deep (H1-coil) transcranial magnetic stimulation (dTMS) is a novel TMS modality with established efficacy for unipolar depression. We conducted a randomized sham-controlled trial to evaluate the efficacy and safety of dTMS in treatment-resistant BD patients. Patients received 20 sessions of active or sham dTMS over the left dorsolateral prefrontal cortex (H1-coil, 55 18 Hz 2 s 120% MT trains). The primary outcome was changes in the 17-item Hamilton Depression Rating Scale (HDRS-17) from baseline to endpoint (week 4). Secondary outcomes were changes from baseline to the end of the follow-up phase (week 8), and response and remission rates. Safety was assessed using a dTMS adverse effects questionnaire and the Young Mania Rating Scale to assess treatment-emergent mania switch (TEMS). Out of 50 patients, 43 finished the trial. There were 2 and 5 dropouts in the sham and active groups, respectively. Active dTMS was superior to sham at end point (difference favoring dTMS=4.88; 95% CI 0.43 to 9.32, p=0.03) but not at follow-up. There was also a trend for greater response rates in the active (48%) vs sham (24%) groups (OR=2.92; 95% CI=0.87 to 9.78, p=0.08). Remission rates were not statistically different. No TEMS episodes were observed. Deep TMS is a potentially effective and well-tolerated add-on therapy in resistant bipolar depressed patients receiving adequate pharmacotherapy.

Dorsal Anterior Cingulate Lactate and Glutathione Levels in Euthymic Bipolar I Disorder: 1H-MRS Study

OBJECTIVE

Oxidative stress and mitochondrial dysfunction are 2 closely integrated processes implicated in the physiopathology of bipolar disorder. Advanced proton magnetic resonance spectroscopy techniques enable the measurement of levels of lactate, the main marker of mitochondrial dysfunction, and glutathione, the predominant brain antioxidant. The objective of this study was to measure brain lactate and glutathione levels in bipolar disorder and healthy controls.

METHODS

Eighty-eight individuals (50 bipolar disorder and 38 healthy controls) underwent 3T proton magnetic resonance spectroscopy in the dorsal anterior cingulate cortex (2x2x4.5cm(3)) using a 2-D JPRESS sequence. Lactate and glutathione were quantified using the ProFit software program.

RESULTS

Bipolar disorder patients had higher dorsal anterior cingulate cortex lactate levels compared with controls. Glutathione levels did not differ between euthymic bipolar disorder and controls. There was a positive correlation between lactate and glutathione levels specific to bipolar disorder. No influence of medications on metabolites was observed.

CONCLUSION

This is the most extensive magnetic resonance spectroscopy study of lactate and glutathione in bipolar disorder to date, and results indicated that euthymic bipolar disorder patients had higher levels of lactate, which might be an indication of altered mitochondrial function. Moreover, lactate levels correlated with glutathione levels, indicating a compensatory mechanism regardless of bipolar disorder diagnosis.

Finasteride Quantification in Human Plasma by High-Performance Liquid Chromatography Coupled to Electrospray Ionization Tandem Mass Spectrometry. Application to a Comparative Pharmacokinetics Study

A specific, fast and sensitive LC-MS/MS assay was developed for the determination of finasteride in human plasma using betamethsone dipropionate as the internal standard (IS). The limit of quantification was 1.0 ng/ml and the method was linear in the range of 1.0-25.0 ng/ml. The retention times were 0.75 min for finasteride and 0.85 min for IS. Method intra-batch precision and accuracy ranged from 3.6 to 7.1%, and 96.6 to 103.9%, respectively. Inter-batch precision ranged from 2.5 to 3.4%, while Inter-batch accuracy ranged from 100.3 to 103.5%. The analytical method was applied to evaluate the pharmacokinetic and relative bioavailability of 2 different pharmaceutical formulations containing 1.0 mg of finasteride. This study evaluated 38 volunteers in a randomized, 2-period crossover study with 7 days washout period between doses. The geometric mean and respective 90% CI of finasteride test/reference percent ratios were 95.68% (91.2 - 104.6%) for Cmax, 97.5% (92.1-103.3%) for AUC0-t and 98.1 (92.67-103.8) for AUC0-inf. Based on the 90% confidence interval of the individual ratios (test formulation/reference formulation) for Cmax and AUC0-inf, it was concluded that the test formulation is bioequivalent to the reference one with respect to the rate and extent of absorption of finasteride.

Lithium efficacy in bipolar depression with flexible dosing: A six-week, open-label, proof-of-concept study

Lithium has a narrow therapeutic index with a subtle balance between effectiveness and adverse effects. Current guidelines recommend the use of lithium as a treatment for acute bipolar depression; however, the therapeutic range for the treatment has not been fully defined. Recently, the adjunctive lower lithium dose in bipolar depression has revealed potential efficacy; however, no study has investigated it predominantly in monotherapy. In this open-label, proof-of-concept study, 31 individuals with bipolar disorder during a depressive episode were randomized and 29 were followed up for six weeks with flexible lithium dosing. All subjects had a 21-item Hamilton Rating Scale for Depression (HAM-D) score of ≥18 at baseline. Subjects were divided into two groups, with higher (Li ≥0.5 mEq/l) or lower (Li <0.5 mEq/l) blood lithium levels. Response and remission rates were evaluated using the HAM-D scores. Following 6 weeks of lithium treatment, the remission rate for all patients was 62.0%. The plasma lithium levels did not impact the clinical response. However, subjects with higher blood lithium levels had an increased prevalence of nausea, restlessness, headaches and cognitive complaints. The results indicate that the lithium dose for the treatment of bipolar depression in an individual should be based on the clinical efficacy and side-effects. In the context of personalized psychiatric treatments, it is necessary to evaluate the therapeutic action of lithium with individual regimens in order to develop more tolerable and effective treatment approaches.

Leukocyte telomerase activity and antidepressant efficacy in bipolar disorder

Telomeres are DNA-protein complexes that cap linear DNA strands, protecting DNA from damage. Recently, shorten telomeres length has been reported in bipolar disorder (BD) and depression. The enzyme telomerase regulates telomeres׳ length, which has been associated with cellular viability; however it is not clear how telomerase may be involved in the pathophysiology and therapeutics of BD. In the present study, leukocyte telomerase activity was assessed in 28 medication-free BD depressed individuals (DSM-IV-TR criteria) at baseline and after 6 weeks of lithium therapy (n=21) also matching with 23 healthy controls. There was no difference between telomerase activity in subjects with BD depression (before or after lithium) and controls. Improvement of depressive symptoms was negatively associated with telomerase activity after 6 weeks of lithium therapy. This is the first study describing telomerase activity in BD research. Overall, telomerase activity seems not directly involved in the pathophysiology of short-term BD. Lithium׳s antidepressant effects may involve regulation at telomerase activity. Further studies with larger samples and long-term illness are also warranted.

The CACNA1C risk allele selectively impacts on executive function in bipolar type I disorder

OBJECTIVE

Calcium channels are important for converting electrical activity into biochemical events. A single nucleotide polymorphism (SNP) (rs1006737) in the CACNA1C gene has been strongly associated with increased risk for Bipolar disorder (BD) in genome-wide association studies. Recently, this same SNP has been reported to influence executive function in schizophrenia and controls, but it remains unclear whether this SNP affects behaviour, especially cognition in subjects with BD.

METHOD

A total of 109 BD type I subjects and 96 controls were genotyped for CACNA1C rs1006737 and assessed with an executive function tests battery [Wechsler Adult Intelligence Scale III (WAIS-III) Letter-Number Sequence subtest (WAIS-LNS), digit span (WAISDS), trail making test (TMT), and WCST (Wisconsin Card Sorting Test)].

RESULTS

In patients with BD, the CACNA1C genotype Met/Met was associated with worse performance on all four executive function tests compared to Val/Val. No influence of CACNA1C was observed in the cognitive performance of healthy controls.

CONCLUSION

Our data indicate for the first time that the CACNA1C risk allele is likely associated with executive dysfunction as a trait in BD, as this association was found regardless the presence of mood symptoms. Larger studies should evaluate the potential influence of CACNA1C on other cognitive domains in BD.

Psychological profile (anxiety and depression) in patients with oral lichen planus: a controlled study

AIM

The influence of psychological disturbances in oral lichen planus (OLP) still bears some controversy. This study aimed at assessing levels of anxiety and depression in OLP patients and control subjects, using a self-report scale questionnaire.

METHODS

This cross-sectional study comprised 91 consecutive OLP patients (71 female and 20 male; mean age 52.9 years) and 87 subjects as a control group (69 female and 18 male; mean age 52.7 years). Data collected of both groups included age, sex, race, medical records and systemic disease. Anxiety and depression levels were assessed using, respectively, the State-Trait Anxiety Inventory (STAI-T) and Center for Epidemiologic Studies Depression Scale (CES-D). Data were analyzed by Chi-square and Fisher's exact tests as appropriate, and by Logistic regression analysis.

RESULTS

No statistically significant difference was found when the level of anxiety and depression was compared between the OLP and control using Chi-square and Fisher's tests (P>0.05). Logistic regression analysis showed that the score in 2 out of 20 items of the STAI-T scale (but none of the CES-D) was significantly higher in OLP patients (P<0.05). The analysis by gender showed that the female and male OLP patients presented a significantly higher score for one item in the STAI-T scale (respectively question 4 and 20) but none in the CES-D scale, as compared with that of the control group (P<0.05).

CONCLUSION

Our findings do not support that either anxiety or depression has any role in the development of OLP lesions.

Efficacy of psychoeducation on symptomatic and functional recovery in bipolar disorder

OBJECTIVE

To evaluate the efficacy of psychoeducation in the symptomatic and functional recovery, and quality of life (QoL) in a sample of patients with bipolar disorder (BD).

METHOD

The sample comprised 55 patients with BD I and II in remission (Young Mania Rating Scale ≤6 and Hamilton Depression Rating Scale ≤7). Out-patients were matched assigned to receive 16 sessions of psychoeducation [experimental group (EG)] or 16 sessions of placebo without psychoeducation [control group (CG)]. Groups were evaluated at study baseline, midpoint, endpoint, and at 6- and 12-month follow-ups.

RESULTS

No significant differences between the groups were found for the variables evaluated (mood symptoms, functioning and QoL), except for overall clinical improvement, subjectively perceived by EG subjects. Both groups showed a trend toward improved clinical global impression and QoL (environmental). No reduction in mood symptoms or improvement in psychosocial functioning was observed. Psychosocial treatment compliance was positively correlated with global functioning, social adjustment, sociability, and global clinical impression.

CONCLUSION

Sixteen session psychoeducation seems to be ineffective to prevent mood episodes or improve functioning in a sample of bipolar patients.

Early improvement of psychotic symptoms with lithium monotherapy as a predictor of later response in mania

Although lithium has been the first line agent in the treatment of bipolar disorder (BD), few studies have evaluated lithium's efficacy in mania with psychosis and its association with later response. Furthermore, given the widespread concern about antipsychotic side effects, answering a question about whether lithium alone can manage to treat both psychotic and non-psychotic mania seems a very relevant one. The present study addresses the antipsychotic efficacy of lithium monotherapy in acute mania and early improvement of psychotic symptoms as a predictor of later response of manic symptoms. Forty-six patients presenting a manic episode (32 with psychotic features and 14 subjects without psychotic features) were treated for 4 weeks with lithium monotherapy and evaluated weekly using the Young Mania Rating Scale (YMRS). Subjects with rapid cycling, substance abuse/dependence, or mixed episodes were excluded. The overall antimanic efficacy of lithium in psychosis vs. non-psychosis groups was evaluated. In addition, early improvement of psychotic symptoms and its prediction of subsequent response (>50% decrease in total YMRS scores) or remission were evaluated. Lithium showed a similar efficacy in both psychosis and non-psychosis mania. Early improvement of psychotic symptoms was associated with clinical response and remission at endpoint.

Pharmacological approaches in bipolar disorders and the impact on cognition: a critical overview

OBJECTIVE

Historically, pharmacological treatments for bipolar disorders (BD) have been associated with neurocognitive side-effects. We reviewed studies which assessed the impact of several psychopharmacological drugs on the neurocognitive function of BD patients.

METHOD

The PubMed database was searched for studies published between January 1980 and February 2011, using the following terms: bipolar, bipolar disorder, mania, manic episode, or bipolar depression, cross-referenced with cognitive, neurocognitive, or neuropsychological, cross-referenced with treatment.

RESULTS

Despite methodological flaws in the older studies and insufficient research concerning the newer agents, some consistent findings emerged from the review; lithium appears to have definite, yet subtle, negative effects on psychomotor speed and verbal memory. Among the newer anticonvulsants, lamotrigine appears to have a better cognitive profile than carbamazepine, valproate, topiramate, and zonisamide. More long-term studies are needed to better understand the impact of atypical antipsychotics on BD patients' neurocognitive functioning, both in monotherapy and in association with other drugs. Other agents, like antidepressants and cognitive enhancers, have not been adequately studied in BD so far.

CONCLUSION

Pharmacotherapies for BD should be chosen to minimize neurocognitive side-effects, which may already be compromised by the disease process itself. Neurocognitive evaluation should be considered in BD patients to better evaluate treatment impact on neurocognition. A comprehensive neuropsychological evaluation also addressing potential variables and key aspects such as more severe cognitive deficits, comorbidities, differential diagnosis, and evaluation of multiple cognitive domains in longitudinal follow-up studies are warranted.

Differences in synthesis and absorption of cholesterol of two effective lipid-lowering therapies

Effective statin therapy is associated with a marked reduction of cardiovascular events. However, the explanation for full benefits obtained for LDL cholesterol targets by combined lipid-lowering therapy is controversial. Our study compared the effects of two equally effective lipid-lowering strategies on markers of cholesterol synthesis and absorption. A prospective, open label, randomized, parallel design study, with blinded endpoints, included 116 subjects. We compared the effects of a 12-week treatment with 40 mg rosuvastatin or the combination of 40 mg simvastatin/10 mg ezetimibe on markers of cholesterol absorption (campesterol and β-sitosterol), synthesis (desmosterol), and their ratios to cholesterol. Both therapies similarly decreased total and LDL cholesterol, triglycerides and apolipoprotein B, and increased apolipoprotein A1 (P < 0.05 vs baseline for all). Simvastatin/ezetimibe increased plasma desmosterol (P = 0.012 vs baseline), and decreased campesterol and β-sitosterol (P < 0.0001 vs baseline for both), with higher desmosterol (P = 0.007) and lower campesterol and β-sitosterol compared to rosuvastatin, (P < 0.0001, for both). In addition, rosuvastatin increased the ratios of these markers to cholesterol (P < 0.002 vs baseline for all), whereas simvastatin/ezetimibe significantly decreased the campesterol/cholesterol ratio (P = 0.008 vs baseline) and tripled the desmosterol/cholesterol ratio (P < 0.0001 vs baseline). The campesterol/cholesterol and β-sitosterol/cholesterol ratios were lower, whereas the desmosterol/cholesterol ratio was higher in patients receiving simvastatin/ezetimibe (P < 0.0001 vs rosuvastatin, for all). Pronounced differences in markers of cholesterol absorption and synthesis were observed between two equally effective lipid-lowering strategies.

Does BDNF genotype influence creative output in bipolar I manic patients?

INTRODUCTION

Creativity is a complex human ability influenced by affective and cognitive components but little is known about its underlying neurobiology. Bipolar Disorder (BD) is highly prevalent among creative individuals. Brain-derived neurotrophic factor (BDNF) is the most widely distributed neurotrophic factor, and has been implicated in the pathophysiology of BD. In contrast to the better functioning of the BDNF polymorphism (Val(66)Met) Val allele, the Met allele decreases BDNF transport and has been associated with worsened performance on several cognitive domains in euthymic BD subjects and controls. We hypothesized that the Val allele is associated with increased creativity in bipolar disorder.

MATERIALS AND METHODS

Sixty-six subjects with BD (41 in manic and 25 in depressive episodes) and 78 healthy volunteers were genotyped for BDNF Val(66)Met and tested for creativity using the Barrow Welsh Art Scale (BWAS) and neuropsychological tests.

RESULTS

Manic patients with the Val allele (Met-) had higher BWAS scores than Met+ carriers. This relationship was not observed among patients in depressive episodes or among control subjects. BDNF Met allele status showed no association with cognitive function in any of the groups.

CONCLUSION

As postulated, these findings suggest that the better functioning allele of BDNF may selectively facilitate creative thinking in subjects with manic episodes, but not in controls or depressives. Further studies exploring the role of BDNF in the neurobiology of creativity in BD and in euthymic phases are warranted.

ESPECTRA: searching the bipolar spectrum in eating disorder patients

BACKGROUND

Bipolar Disorder (BD) is a chronic, recurrent and highly prevalent illness. Despite the need for correct diagnosis to allow proper treatment, studies have shown that reaching a diagnosis can take up to ten years due to the lack of recognition of the broader presentations of BD. Frequent comorbidities with other psychiatric disorders are a major cause of misdiagnosis and warrant thorough evaluation.

METHODS/DESIGN

ESPECTRA (Occurrence of Bipolar Spectrum Disorders in Eating Disorder Patients) is a single-site cross-sectional study involving a comparison group, designed to evaluate the prevalence of bipolar spectrum in an eating disorder sample. Women aged 18-45 years will be evaluated using the SCID-P and Zurich criteria for diagnosis and the HAM-D, YOUNG, SCI-MOODS, HCL-32, BIS-11, BSQ, WHOQoL and EAS instruments for rating symptoms and measuring clinical correlates.

DISCUSSION

The classificatory systems in psychiatry are based on categorical models that have been criticized for simplifying the diagnosis and leading to an increase in comorbidities. Some dimensional approaches have been proposed aimed at improving the validity and reliability of psychiatric disorder assessments, especially in conditions with high rates of comorbidity such as BD and Eating Disorder (ED). The Bipolar Spectrum (BS) remains under-recognized in clinical practice and its definition is not well established in current diagnostic guidelines. Broader evaluation of psychiatric disorders combining categorical and dimensional views could contribute to a more realistic understanding of comorbidities and help toward establishing a prognosis.

LICAVAL: combination therapy in acute and maintenance treatment of bipolar disorder

BACKGROUND

The challenge of Bipolar Disorder (BD) treatment is due to the complexity of the disease. Current guidelines represent an effort to help clinicians in their everyday practice but still have limitations, specially concerning to long term treatment. LICAVAL (efficacy and tolerability of the combination of LIthium and CArbamazepine compared to lithium and VALproic acid in the treatment of young bipolar patients) study aim to evaluate acute and maintenance phase of BD treatment with two combined drugs.

METHODS

LICAVAL is a single site, parallel group, randomized, outcome assessor blinded trial. BD I patients according to the DSM-IV-TR, in depressive, manic,/hypomanic or mixed episode, aged 18 to 35 years are eligible. After the diagnostic assessments, the patients are allocated for one of the groups of treatment (lithium + valproic acid or lithium + carbamazepine). Patients will be followed up for 8 weeks in phase I (acute treatment), 6 months in phase II (continuation treatment) and 12 months in phase III (maintenance treatment). Outcome assessors are blind to the treatment. The main outcome is the evaluation of changes in mean scores on CGI-BP-M between baseline and endpoint at the end of each phase of the study.

RESULTS

LICAVAL is currently in progress, with patients in phase I, II or III. It will extended until august 2012.

CONCLUSIONS

Trials comparing specific treatments efficacy in BD (head to head) can show relevant information in clinical practice. Long term treatment is an issue of great important and should be evaluated carefully in more studies as long as BD is a chronic disease.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT00976794.

Bioavailability of two oral suspension and two oral tablet formulations of nimesulide 100 mg in healthy Brazilian adult subjects

A specific, fast and sensitive high performance liquid chromatography coupled to an electro spray tandem triple quadrupole mass spectrometer (LC-MS/MS) assay was developed for the determination of nimesulide in human plasma using carbamazepine as the internal standard. The lower limit of quantification (LLOQ) was 50 ng/ml and the calibration curves were linear in the concentration range of 50 - 6,000 ng/ml. Method inter-batch precision and accuracy ranged from 2.78 to 10.80%, and 94.92 to 102.46%, respectively. Intra-batch precision ranged from 2.44 to 7.74%, while intra-batch accuracy ranged from 91.70 to 104.73%. The analytical method was applied to evaluate the pharmacokinetic and relative bioavailability of two different pharmaceutical formulations containing nimesulide, one tablet and one oral suspension, manufactured by the same pharmaceutical factory, comparing with two reference Nisulid formulations in 52 volunteers of both sexes previously divided in two groups of 26 subjects (13 men and 13 females each group). The test tablet formulation was not bioequivalent to the Nisulid 100 mg tablet with respect to the rate of absorption, but was bioequivalent according to the extent of drug absorption. On the other hand, since the 90% CI for Cmax, AUC0-t and AUCinf were within the 80 - 125% interval in the oral suspension study, it was concluded that test oral suspension were bioequivalent to Nisulid 50 mg/ml with respect to both the rate and extent of absorption.

Resolution of sexual dysfunction during acute treatment of major depression with milnacipran

OBJECTIVE

The sexual function and enjoyment questionnaire (SFEQ) was developed to assess and detect changes in sexual function in men and women. The aim of the present study was to use the SFEQ to evaluate the effects of the serotonin-noradrenaline reuptake inhibitor, milnacipran, in the treatment of depression in two culturally different populations.

METHODS

The SFEQ was employed in two studies investigating milnacipran in the treatment of major depression: a 12-week open study in Brazil and a 6-week randomised controlled study in Europe.

RESULTS

At endpoint, 61.3% (Brazil) and 78.4% (Europe) of patients had >or=50% reduction of baseline Hamilton Depression Rating (HAMD) score. All SFEQ items showed improvements in sexual function in both studies at endpoint, 60% (Brazil) and 56% (Europe) of patients stating that their sexual desire was as great as or greater than it had been before their depressive episode.

CONCLUSIONS

Milnacipran appears to improve sexual function in parallel with improvement in other symptoms of depression. The SFEQ is a sensitive instrument for measuring changes in sexual function and appears to be unaffected by cultural differences as shown by similar findings in Brazil and Europe.

A double-blind comparison of the effect of the antipsychotics haloperidol and olanzapine on sleep in mania

The effects of haloperidol and olanzapine on polysomnographic measures made in bipolar patients during manic episodes were compared. Twelve DSM-IV mania patients were randomly assigned to receive either haloperidol (mean +/- SD final dosage: 5.8 +/- 3.8 mg) or olanzapine (mean +/- SD final dosage: 13.6 +/- 6.9 mg) in a 6-week, double-blind, randomized, controlled clinical trial. One-night polysomnographic evaluation was performed before and after the haloperidol or olanzapine treatment. Psychopathology and illness severity were rated respectively with the Young Mania Rating Scale (YMRS) and the Clinical Global Impressions - Bipolar version (CGI-BP). There was a significant improvement in the YMRS and CGI-BP scores at the end of the study for both groups. Mixed ANOVA used to compare the polysomnographic measures of both drugs demonstrated significant improvement in sleep measures with olanzapine. In the olanzapine group, statistically significant time-drug interaction effects on sleep continuity measures were observed: sleep efficiency (mean +/- SEM pre-treatment value: 6.7 +/- 20.3%; after-treatment: 85.7 +/- 10.9%), total wake time (pre-treatment: 140.0 +/- 92.5 min; after-treatment: 55.2 +/- 44.2 min), and wake time after sleep onset (pre-treatment: 109.7 +/- 70.8 min; after-treatment: 32.2 +/- 20.7 min). Conversely, improvement of polysomnographic measures was not observed for the haloperidol group (P > 0.05). These results suggest that olanzapine is more effective than haloperidol in terms of sleep-promoting effects, although olanzapine is comparatively as effective as haloperidol in treating mania. Polysomnography records should provide useful information on how manic states can be affected by psychopharmacological agents.

Efficacy of hormone therapy with and without methyltestosterone augmentation of venlafaxine in the treatment of postmenopausal depression: a double-blind controlled pilot study

OBJECTIVE

This study evaluated the augmentation of venlafaxine with hormone therapy in the treatment of postmenopausal depression. The hormones evaluated were estrogen (0.625 mg) in combination with medroxyprogesterone acetate (2.5 mg) and methyltestosterone (2.5 mg).

DESIGN

Seventy-two menopausal women (mean age: 53.6 +/- 4.27 years) diagnosed with depression (Montgomery-Asberg Depression Rating Scale [MADRS] scores > or = 20) were treated with venlafaxine and one of the following hormone therapy combinations, in a double-blind regimen: estrogen + medroxyprogesterone + methyltestosterone (group 1, n = 20); estrogen + medroxyprogesterone acetate (group 2, n = 20); methyltestosterone only (group 3, n = 16); and no hormone therapy (group 4, n = 16). Study duration was 24 weeks. Primary efficacy outcome was remission according to the MADRS, whereas secondary efficacy measures included the Clinical Global Impression (CGI), Blatt-Kupperman Index, and Women's Health Questionnaire (WHQ).

RESULTS

Forty-eight patients completed the study. All groups showed significant improvement from baseline. Group 3 demonstrated significant improvement on the MADRS compared with placebo (group 4) at weeks 20 (P = 0.048) and 24 (P = 0.030); effect size 8.04 (0.83; 15.26) (P = 0.029), but also had the highest dropout rate. Groups 1 and 3 had significant CGI improvement rates compared with placebo: 42.23% (P = 0.012) and 44.45% (P = 0.08), respectively. There were no differences in the WHQ or BKI scores among the groups.

CONCLUSIONS

Methyltestosterone 2.5 mg had the highest effect size compared with placebo, but the high dropout rate prevented its efficacy from being determined. Estrogen plus medroxyprogesterone, combined with methyltestosterone or otherwise, demonstrated a trend toward increased efficacy of venlafaxine. Further larger-scale clinical trials are needed to elucidate the findings of this pilot study.

Digoxin bioequivalence study: determination in human plasma by microparticle enzyme immunoassay

OBJECTIVE

In this study a bioanalytical method for digoxin quantification was developed using Abbott AxSYM Digoxin II with fluorescence detection to assess the bioequivalence of two digoxin tablet formulations (Digox 0.25 mg tablet from Pharlab Ind. Ltd., Brazil as test formulation and Digoxin 0.25 mg tablet from Laboratório Glaxo SmithKline, Brazil as reference formulation).

MATERIAL AND METHODS

30 healthy volunteers (both sexes) received a single oral dose of digoxin in an open, randomized, two-period crossover study with a seven half-life washout interval of at least (21 days). Plasma samples were obtained over a 288-h interval after each oral administration of digoxin. The present method utilizes microenzyme particle immunoassay technology, in which the digoxin in the sample binds to anti-digoxin-coated microparticles and after separation; digoxin-alkaline phosphatase conjugate binds to the available sites remaining. Digoxin concentrations are calculated from the fluorescent products generated as a result of substrate (4-methylumbelliferyl) passage through the matrix cell.

RESULTS

The method was shown to be specific and sensitive with good accuracy and precision. The geometric mean and 90% confidence intervals (CI) for the Digox/Digoxin ratio were 107.62% (96.71 - 119.80%) for AUC0-t, 97.15% (80.54 - 117.19%) for AUC0-inf, and 91.23% (83.55 - 99.62%) for Cmax.

CONCLUSION

Since the 90% CI for the parameters were all within the 80 - 125% interval proposed by the US Food and Drug Administration Agency, the two formulations were considered bioequivalent in terms of rate and extent of absorption.

Meloxicam determination in human plasma by high-performance liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS) in Brazilian bioequivalence studies

OBJECTIVE

In this study, the bioavailability of 2 meloxicam 15 mg tablet formulations was compared. A single dose of each formulation was administered to 24 healthy volunteers (12 males and 12 females).

MATERIAL AND METHODS

The study was conducted using an open, randomized and crossover design with a 2-week washout interval. The plasma samples were obtained over a 96-hour interval and meloxicam concentrations were analyzed by high-performance liquid chromatography (an agilent) coupled to an API 2000 turboionspray tandem mass spectrometry (LC-MS-MS). An electrospray ionization (ESI) source operating in the positive ion mode, using a cross flow counter electrode and set for the multiple reaction monitoring (MRM) was employed. The plasma protein precipitate was reconstituted with acetonitrile/water + 10 mM acetic acid (20/80, v/v) and injected in a Prevail C8 5 microm (150 mm x 4.6 mm i.d.) analytical column with reverse-phase liquid chromatography. The retention time observed for meloxicam and tenoxicam (internal standard) was 1.8 and 1.4 minutes, respectively. The mean recovery of meloxicam was 95.9% and the limit ofquantification was 0.02 microg/ml.

RESULTS

The geometric mean of meloxicam/movatec 15 mg individual % ratio was 101.3% for AUC(last), 99.9% for AUC(0-infinity) and 107.7% for C(max). The 90% confidence intervals were 97.3 - 105.4%, 96.0 - 104.0% and 98.8 - 117.4%, respectively.

CONCLUSION

Since the 90% CI for both AUC(Iast), AUC(0-infinity) and C(max), ratios were all inside the 80 - 125% interval proposed by the US Food and Drug Administration Agency and accepted by Brazilian ANVISA (Sanitary Surveillance Agency), it was concluded that the meloxicam formulation produced by Merck S.A. lndústrias Químicas is bioequivalent to the movatec formulation regarding both the rate and extent of absorption. This assay method was faster, more simple, specific, precise and accurate in determining the bioequivalence of meloxicam than any method previously described.

Pharmacological activities investigation of crude extracts and fractions from Qualea grandiflora Mart

This study investigates pharmacological activities of crude hydroalcoholic extract and fractions of Qualea grandiflora Mart. leaves employing different experimental models using mice. The treatment with crude hydroalcoholic extract (EH) in a dose of 500 mg/kg, i.p. caused: signs of central nervous system depressant action in the Hippocratic screening test, confirmed by the potentiation of sodium pentobarbital sleeping time. Increasing in the latency time of hot plate assay that indicate an analgesic effect; significantly delaying of the onset of clonic PTZ convulsions, increasing in the time for death, suppressing of the tonic PTZ convulsion, and decreasing of severity and number of convulsions. The median lethal dose of EH was 1.321 mg/kg. The convulsions induced by PTZ, ethyl ether fraction (300 mg/kg, i.p.) was more active in increasing the latency time for first convulsion, moreover, the hexane fraction, at the same dose, was more active in increasing the time for death and/or avoiding the death. Both did not cause disturbance in motor coordination at the dose of 500 mg/kg, assessed by rotarod test. These results suggest that the crude extract of leaves of Qualea grandiflora Mart. has a central nervous system depressant action, an analgesic effect and behave as a potential anticonvulsant.

Melatonin levels in drug-free patients with major depression from the southern hemisphere

The secretion of melatonin has been shown as abnormal in some depressed patients, but most such studies were conducted in the northern hemisphere and with severely depressed inpatients. The aim of this study was to evaluate melatonin excretion profiles in major depressive outpatients from São Paulo, Brazil, individually matched to well-screened healthy volunteers to examine whether melatonin abnormalities are also present in patients from the southern hemisphere, and in less severely ill patients. We analyzed 32 drug-free, depressed outpatients and 32 psychiatrically healthy volunteers matched for age and gender. We also examined a set of 15 drug-free depressed outpatients and 15 healthy volunteers that were matched not only for age and gender, but also for body mass index and season, all factors known to influence melatonin excretion in humans. All patients fulfilled DSM-IV criteria for major depression. We evaluated major urinary metabolite of melatonin, 6-sulphatoxymelatonin (aMT6s), produced over 24 h and divided into four periods (06:00-12:00, 12:00-08:00, 18:00-24:00 and 24:00-06:00 h). aMT6s measurements during the 24 and 6 h intervals were similar in the 32 depressed patients and 32 healthy volunteers matched for age and gender; further matching for body mass index and season did not alter the results. Our study supports others in which depressed patients were found to have similar melatonin levels than healthy volunteers. Melatonin excretion has been considered a physiological index for noradrenergic function, which in some studies were found to be altered than depressed patients. It is conceivable that the alteration of nocturnal melatonin in depressed patients occurs only in more severe depression.

Comparative bioavailability of clarithromycin formulations in healthy Brazilian volunteers

OBJECTIVE

To compare the bioavailability of clarithromycin 500 mg tablets (Merck S.A Industrias Quimicas, Sao Paulo, SP, Brazil, used as test formulation) and Klaricid (Abbott Laboratórios do Brasil Ltda, Sao Paulo, SP, Brazil, used as reference formulation) in 24 healthy volunteers.

MATERIAL AND METHODS

The study was conducted using an open, randomized, two-period crossover design with one-week interval between doses. Blood samples were collected at pre-dose, 0.33, 0.66, 1, 1.33, 1.66, 2, 2.5, 3, 4, 6, 8, 10, 12, 16, 20 and 24 hours after the administration. AUC was calculated by the trapezoidal rule extrapolation method. Cmax and tmax were compiled from the plasmatic concentration-time data. Analysis of variance was carried out using logarithmically transformed AUC(0-inf), AUC(0-24 h), Cmax and untransformed tmax.

RESULTS

Intraindividual coefficient of variation (CV%) values were 14.25% and 12.62%, respectively for Cmax and AUC(0-24 h). The geometric mean values (+/- SD) for AUC(0-24 h) (microg x h/ml), AUC(0-inf) (microg x h/ml), and Cmax (microg/ml) for test medication were 18.56 (+/- 6.87), 18.8 (+/- 5.70) and 2.45 (+/- 0.88); the obtained values for reference medication were 18.29 (+/- 5.39), 19.10 (+/- 7.21) and 2.5 (+/- 0.69). 90% Cl for clarithromycin geometric mean of AUC(0-24 h), AUC(0-inf) and Cmax ratios (test/reference) were: 93.6-105.9%, 93.8-106.2% and 89- 103.2%. CCONCLUSION The test medication was considered bioequivalent to the reference medication based on the rate and extent of absorption.

Efficacy of electroconvulsive therapy in treatment-resistant bipolar disorder: a case series

The response to electroconvulsive therapy for six bipolar patients after pharmacotherapy failure is discussed.

METHODS

Inclusion criteria were as follows: (1) bipolar mood disorder, manic, depressive or mixed episode (DSM-IV); (2) failure of pharmacotherapy, that is, for mania, manic episode unresponsive to at least 2 adequate antimanic trials for 6 weeks; and for bipolar depression, bipolar depressive episode unresponsive to at least 2 adequate antidepressant trials for 8 weeks. The patients underwent 12 bilateral sessions of ECT 3 times per week. Clinical response was considered a reduction of 50% or greater in the Young Mania Rating Scale (YMRS) and in the Hamilton Rating Scale for Depression-21 items (HAMD-21). Final YMRS <6 and HAMD-21 <8 defined remission.

RESULTS

Six of the 9 referred patients consented to be submitted to ECT. Four were male, with ages ranging from 29 to 61 years, and their age at onset ranged from 19 to 49 years. Four showed psychotic features. All responded to ECT.

Cyclosporine bioequivalence study: quantification using fluorescence polarization immunoassay (FPIA) and radioimmunoassay (RIA)

OBJECTIVE

The aim of study was to compare the bioavailability of 2 cyclosporine capsule formulations (100 mg; Sigmasporin Microoral from Novaquímica Divisão Nature's Plus Farmacêutica Ltd., Brazil, as test formulation and Sandimmune Neoral from Novartis Biociências S.A., Brazil, as reference formulation) in 24 healthy male volunteers.

METHODS

The study was open, randomized, with a 2-period crossover, a 1-week washout interval between doses. Blood samples were obtained over a 12-hour interval after each oral administration of cyclosporine (2 capsules of 100 mg of each formulation). Cyclosporine blood concentrations were quantified using a fluorescence polarization immunoassay (FPIA) method provided by Abbott Axsym System and Cyclo-Trac SP. Whole-blood radioimmuoassay (RIA) kit was provided by DiaSorin. These assays provided concentration-time curves for cyclosporine in blood concentration from which the following pharmacokinetic parameters were obtained: AUC(last), AUC(inf), Cmax.

RESULTS

Geometric mean and 90% confidence intervals (CI) of Microoral/Neoral as percent ratios were 94.5% (90.8-98.4%) for AUC(last), 93.8% (89.7-98.1%) for AUC(inf), and 98.1% (94.5-101.8%) for Cmax when cyclosporine was determined using FPIA and 96.1% (91.9 to 100.6%) for AUC(last), 95.2% (90.2-100.5%) for AUC(inf), and 99.4% (96.4-102.4%) for Cmax using RIA.

CONCLUSION

Since the 90% CI for Cmax, AUC(last) and AUC(inf) ratio were within the 80-125% interval proposed by US-FDA, it is concluded that Sigmasporin Microoral 100 mg capsule formulation is bioequivalent to Sandimmune Neoral 100 mg capsule formulation with regard to both rate and the extent of absorption.

Bioequivalence study of two fluconazole capsule formulations in healthy volunteers

OBJECTIVE

To compare the bioavailability of a fluconazole 150 mg capsule formulation from Laboratório Teuto Brasileiro Ltd., Brazil (test formulation), and Zoltec 150 mg capsule from Laboratórios Pfizer Ltd., Brazil (reference formulation), in 24 volunteers of both sexes.

MATERIAL AND METHODS

The study was conducted open with randomized 2-period crossover design and a 2-week washout period. Plasma samples were obtained over a 168-hour interval. Fluconazole concentrations were analyzed by combined reversed-phase liquid chromatography and tandem mass spectrometry (LC/MS/MS) with positive ion electrospray ionization using selected ion monitoring method. From the fluconazole plasma concentration vs. time curves the following pharmacokinetic parameters were obtained: AUC(last), AUC(0-inf) and C(max).

RESULTS

Geometric mean of fluconazole/Zoltec 150 mg individual percent ratio was 102.6% for AUC(last), 102.2% for AUC(0-inf) and 109.4% for C(max). The 90% confidence intervals were 97.3-108.2%, 97.0-107.8%, and 103.1-116.0%, respectively.

CONCLUSION

Since the 90% CI for both Cmax, AUC(last) and AUC(0-inf) were within the 80-125% interval proposed by the Food and Drug Administration, it was concluded that fluconazole 150 mg capsule was bioequivalent to Zoltec 150 mg, according to both the rate and extent of absorption.

Social adjustment in depressed patients treated with venlafaxine and amitriptyline

Social dysfunction is often associated with depressive disorders and its evaluation is an important measure of treatment outcome. The aim of this study was to assess the effect of two treatments, venlafaxine and amitriptyline, on the social functioning of depressed patients. Twenty-eight outpatients, meeting criteria for recurrent or single major depressive episodes, took part in a double-blind, 8-week trial with amitriptyline or venlafaxine (maximum of 150 mg/day) and were assessed by the Self-Report Social Adjustment Scale (SAS-SR) before and at the end of treatment. The scale was also applied to a carefully selected non-psychiatric sample. Both drugs showed the same efficacy on a clinical scale, but venlafaxine improved social functioning more than amitriptyline as only venlafaxine-treated patients reached SAS-SR values estimated for normal subjects. This effect might be linked to the higher rate of side-effects observed with amitriptyline.

Validation of the Portuguese version of the Social Adjustment Scale on Brazilian samples

BACKGROUND

Social dysfunction is reported in several psychiatric diseases and its evaluation is becoming an important measure of treatment outcome. The aim of this study was to obtain normative data, to test the validity and the ability of the Portuguese version of the Self-Report Social Adjustment Scale (SAS-SR) to detect different clinical conditions.

METHODS

The Portuguese version of the SAS-SR was applied to a carefully selected non-psychiatric sample, and to depressed, panic, bulimic and cocaine-dependent patients. Depressed and panic patients were evaluated in two different clinical conditions: acutely symptomatic and in remission.

RESULTS

SAS overall and sub-scale scores of the normal sample were consistently lower than all patient groups, indicating better social adjustment in all areas. Panic patients were impaired to a lower level than depressed and cocaine-dependent patients in overall adjustment. Depressed patients in remission, although in better condition, were still impaired in relation to normal subjects in overall social functioning, leisure time and marital areas. In panic patients in remission, normalization was not achieved in overall functioning, work and marital areas.

LIMITATIONS

Sample size was small in some groups and the evaluation was cross-sectional.

CONCLUSIONS

The Portuguese version of SAS-SR is a useful instrument for detecting differences between psychiatric patients and normal subjects and for the evaluation of different clinical conditions, recommending its use in outcome studies.

Quantification of nimesulide in human plasma by high-performance liquid chromatography/tandem mass spectrometry. Application to bioequivalence studies

A method based on liquid chromatography with negative ion electrospray ionization and tandem mass spectrometry is described for the determination of nimesulide in human plasma. Liquid-liquid extraction using a mixture of diethyl ether and dichloromethane was employed and celecoxib was used as an internal standard. The chromatographic run time was 4.5 min and the weighted (1/x) calibration curve was linear in the range 10.0-2000 ng x ml(-1). The limit of quantification was 10 ng x ml(-1), the intra-batch precision was 6.3, 2.1 and 2.1% and the intra-batch accuracy was 3.2, 0.3 and 0.1% for 30, 300 and 1200 ng x ml(-1) respectively. The inter-batch precision was 2.3, 2.8 and 2.7% and the accuracy was 3.3, 0.3 and 0.1% for 30, 300 and 1200 ng x ml(-1) respectively. This method was employed in a bioequivalence study of one nimesulide drop formulation (nimesulide 50 mg x ml(-1) drop, Medley S/A Indústria Farmacêutica, Brazil) against one standard nimesulide drop formulation (Nisulid, 50 mg x ml(-1) drop, Astra Médica, Brazil). Twenty-four healthy volunteers (both sexes) took part in the study and received a single oral dose of nimesulide (100 mg, equivalent to 2 ml of either formulation) in an open, randomized, two-period crossover way, with a 2-week washout interval between periods. The 90% confidence interval (CI) for geometric mean ratios between nimesulide and Nisulid were 93.1-109.6% for C(max), 87.7-99.8% for AUC(last) and 88.1-99.7% for AUC(0-infinity). Since the 90% CI for the above-mentioned parameters were included in the 80-125% interval proposed by the US Food and Drug Administration, the two formulations were considered bioequivalent in terms of both rate and extent of absorption.

Nonadrenergic, noncholinergic relaxation of human isolated corpus cavernosum induced by scorpion venom

OBJECTIVES

To examine the effects of Tityus serrulatus scorpion venom (TSV) on human corpus cavernosum (HCC) using a bioassay cascade. Priapism is occasionally observed in scorpion envenomation, mostly in children.

METHODS

HCC strips were suspended in a cascade system and superfused with aerated and warmed Krebs' solution at 5 mL/min. Noradrenaline (3 micromol/L) was infused to induce a submaximal contraction of the HCC strips. The release of cyclooxygenase products was prevented by infusing indomethacin (6 micromol/L).

RESULTS

N(omega)-nitro-L-arginine methyl ester (10 micromol/L; n = 10) increased the tone of the preparations and significantly reduced (P <0.01) the acetylcholine (ACh) and TSV-induced relaxations. Subsequent infusion of L-arginine (300 micromol/L) partially reversed the increased tone and significantly restored the relaxations induced by TSV and ACh (P <0.01). The soluble guanylyl cyclase inhibitor ODQ (10 micromol/L; n = 8) markedly reduced (P <0.01) the relaxations induced by TSV, ACh, glyceryl trinitrate, and bradykinin. 7-Nitroindazole (10 micromol/L; n = 8) inhibited the relaxations induced by TSV by 84% (P <0.01) and also caused small, but significant, reductions in the ACh and bradykinin-induced HCC relaxations (P <0.05). Atropine (1 micromol/L; n = 6) abolished the relaxations evoked by ACh (P <0.01), but had no effect on those elicited by TSV. Tetrodotoxin (1 micromol/L; n = 6) abolished the relaxations induced by TSV (P <0.01) and also reversed the established TSV-induced relaxation (n = 4).

CONCLUSIONS

Our results indicate that TSV relaxes HCC through the release of nitric oxide from nonadrenergic, noncholinergic (NANC) nerves. The elucidation of the mechanism responsible for the TSV-induced relaxations might be useful for a better understanding of the development of priapism in cases of scorpion envenomation.

Inhaled nitric oxide improves hemodynamics during a venous air infusion (VAI) in dogs

OBJECTIVE

To evaluate the hemodynamic effects of inhaled nitric oxide (NO) during a venous air infusion (VAI) in dogs. We also addressed the question of whether NO therapy changes thromboxane (Tx) A(2) release and nitrate/nitrite production during a VAI.

DESIGN

Prospective trial.

SETTING

University laboratory.

INTERVENTIONS

Anesthetized mongrel dogs received a VAI (0.2 ml x kg(-1)x min(-1)) after the measurement of baseline hemodynamics. Control dogs (n = 8) received no further treatment. After 30 min of VAI, NO 3 ppm inhalation was initiated (n = 7) for 30 min, followed by 30 min without NO inhalation, and then a final 30 min of NO 40 ppm treatment. Hemodynamic variables were registered and arterial and mixed venous blood samples were drawn for gas analysis and for the determinations of serum TxB(2) (by enzyme-linked immunosorbent assay) and nitrate/nitrite (by high-performance liquid chromatography) levels.

RESULTS

The cardiac index increased 24 % and the pulmonary vascular resistance index decreased 30 % during both periods of NO inhalation. Arterial oxygen tension and arterial oxygen saturation were slightly lower after NO therapy. Nitrate/nitrite concentrations were unaltered in the control group and there were no differences between the arterial and mixed venous serum nitrate/nitrite levels. Nitrite concentrations remained below 1 microM in both groups of animals, but the nitrate concentration increased after inhalation of 40 ppm NO. Serum TxB(2) increased after 60 min of VAI in the control group, but there was no increase in NO-treated animals (all p < 0.05)

CONCLUSIONS

Nitrate/nitrite concentrations were unaltered after VAI in dogs. NO therapy attenuated TxA(2) release and improved hemodynamics, but not blood oxygenation, in dogs with a VAI. There were no differences between the responses to 3 ppm and 40 ppm NO.

Pharmacological characterization of kinin-induced relaxation of human corpus cavernosum

OBJECTIVE

To characterize the kinin receptor subtype involved in the relaxation of human isolated corpus cavernosum (HCC) induced by bradykinin (BK), Lys-bradykinin (Lys-BK), Met-Lys-bradykinin (Met-Lys-BK) and des-Arg9-bradykinin, and to investigate whether the kinin-induced relaxation of HCC results from the stimulation of nonadrenergic, noncholinergic (NANC) neurons supplying the cavernosal tissue.

MATERIALS AND METHODS

Excised HCC tissues were immediately placed in Krebs solution and kept at 4 degrees C until use (never > 24 h after removal). HCC was cut in strips of approximately 2 cm, suspended in a cascade system and superfused with oxygenated and warmed Krebs solution at 5 mL/min. After equilibration for approximately 90 min, noradrenaline (3 micromol/L) was infused to induce a submaximal contraction of the HCC strips. The release of cyclo-oxygenase products was prevented by infusing indomethacin (6 micromol/L). HCC strips were calibrated by injecting a single bolus of the nitrovasodilator glyceryl trinitrate (GTN) and the sensitivity of the tissues adjusted electronically to be similar. The agonists (kinins, histamine and acetylcholine) were injected as a single bolus (up to 100 microL) and the relaxation of HCC expressed as a percentage of the submaximal relaxation induced by GTN.

RESULTS

Bradykinin, Lys-BK and Met-Lys-BK significantly relaxed the HCC tissues; on a molar basis, there was no statistical difference among the degrees of relaxation induced by these peptides. The B1 kinin receptor agonist des-Arg9-bradykinin had no effect on the HCC. The infusion of the B2 kinin receptor antagonist Hoe 140 (50 nmol/L) virtually abolished the relaxation induced by BK, Lys-BK and Met-Lys-BK without affecting those induced by acetylcholine and histamine. The infusion of the nitric oxide synthase inhibitor N(omega)-nitro-L-arginine methyl ester increased the tone of the HCC tissues and significantly reduced (P < 0.01) the relaxation induced by BK (74%), Lys-BK (90%), Met-Lys-BK (87%) and acetylcholine (89%) without affecting those induced by GTN. The subsequent infusion of L-arginine (300 micromol/L) partially reversed the increased tone and significantly (P < 0.01) restored the relaxation induced by BK, Lys-BK and Met-Lys-BK. The results were similar with the novel guanylate cyclase inhibitor 1H-[1,2,4] oxadiazolo[4,3,-alquinoxalin-1-one] which reduced by > 95% (P < 0.01) the relaxation induced by BK, Lys-BK, Met-Lys-BK, acetylcholine and GTN. The infusion of the sodium-channel blocker tetrodotoxin had no significant effect on the BK-, GTN- and acetylcholine-induced relaxation of HCC.

CONCLUSION

This study clearly showed the existence of functional B2 kinin receptors in human erectile tissues that when activated lead to the release of NO and hence relaxation of the HCC tissues. As tetrodotoxin failed to affect the kinin-induced relaxation of HCC strips, it is likely that these peptides release NO from the endothelium of sinusoidal capillaries rather than from neuronal sources supplying the cavernosal tissue. Although tissue kallikreins and their components have been found in the male reproductive system, the physiopathological importance of these findings has yet to be elucidated.

Lonomia obliqua caterpillar spicules trigger human blood coagulation via activation of factor X and prothrombin

In southern Brazil, envenomation by larvae of the moth Lonomia obliqua (Walker) may result in blood clotting factor depletion, leading to disseminated intravascular coagulation with subsequent haemorrhage and acute renal failure which may prove fatal. We have examined the effect of a crude extract of spicules from these caterpillars on in vitro hemostasis. The extract alone did not aggregate platelets and had no detectable effect on purified fibrinogen, suggesting that extract induces clot formation by triggering activation of the clotting cascade. In agreement with the presence of thrombin-mediated activity, hirudin prevented clot formation. The extract was found to activate both prothrombin and factor X, suggesting that the depletion of blood clotting factors results from the steady activation of factor X and prothrombin. Heating and diisopropylfluorophosphate abolished the procoagulant activity of the extract, indicating that the active component involved is a protein that may belong to the serine protease family of enzymes. The ability of hirudin to inhibit this coagulant activity suggests that this inhibitor could be beneficial in the treatment of patients envenomed by L. obliqua caterpillars.

Influence of gastric acid secretion blockade and food intake on the bioavailability of a potassium diclofenac suspension in healthy male volunteers

The bioavailability of a single dose of a potassium diclofenac (KDIC) suspension (Flogan, Merck, 7ml, 105 mg) was studied in 13 healthy male volunteers in the fasting state (placebo phase, PLA), after gastric acid secretion blockade (subacute pretreatment with omeprazole, OME phase) and after food intake (FOOD phase). A 14-day washout period between phases was adopted. Serum samples were obtained over a 24 hour interval and the diclofenac concentrations were determined by high pressure liquid chromatography with ultraviolet detection. From the serum diclofenac concentration vs time curves, the AUC[0-infinity] (area under the concentration vs time curves from 0 to infinity), Cmax (maximum achieved concentration), tmax (time to achieve Cmax), Ke (terminal first order elimination constant), half-life values (t1/2) and AUC[0-infinity]/t1/2 ratio as an index of diclofenac clearance, were obtained. All these variables were analyzed using both parametric and non-parametric statistics. In the presence of food, KDIC absorption was delayed (as shown by lower Cmax and greater tmax values) and decreased (as shown by lower AUC[0-infinity] values), and the serum diclofenac concentration vs time curves showed a biphasic pattern. Omeprazole pretreatment did not change the absorption parameters. Both of these treatments altered the diclofenac clearance, as assessed by the AUC[0-infinity]/t1/2, t1/2 and Ke values, although the changes were not considered to be clinically significant, because of the wide therapeutic range for diclofenac. The delay in the rate of diclofenac absorption produced by food intake was not due to an increase in the gastric pH, and could be of particular importance when rapid analgesia is desired.

Comparative bioavailability of two suspension formulations of potassium diclofenac in healthy male volunteers

The bioavailability of two suspension formulations of potassium diclofenac (Flogan, Merck and Cataflam, Ciba-Geigy) were compared in eighteen healthy male volunteers who received a single dose of 7 ml of each suspension (equivalent to 105 mg of potassium diclofenac) in an open randomized two period crossover design, with a fourteen-day washout period between doses. Serum samples were obtained over a 24 hour interval and diclofenac concentrations were determined by HPLC with ultraviolet detection. From the serum diclofenac concentration vs time curves, AUC[0-24] (area under the concentration vs time curves from 0-24 h), Cmax (maximum achieved concentration), Tmax (time to achieve Cmax) and Ke (terminal first order elimination constant) were obtained. Overlapping of Tmax intervals for both formulations was observed, but the important inter-subject variation observed in Cmax ratios did not allow equivalence conclusion for the rate of absorption. Equivalence in the extent of bioavailability between both potassium diclofenac suspension brands was concluded from the analysis of AUC[0-24] ratios.

Epidermal cell outgrowth from CO2 laser- and scalpel-cut explants: implications for wound healing

We set out to determine if the slow healing of CO2 laser-incised skin wounds compared with that of scalpel-incised wounds is the result of an inhibitory effect of the CO2 laser energy on the rate of epithelialization. We compared the rate of epidermal outgrowth from laser- and scalpel-cut explants in vitro. The onset of epidermal cell outgrowth (epiboly) from CO2 laser-incised skin was delayed, but there was no difference in the rate of epidermal cell outgrowth. These studies suggest that a delay in onset of epidermal migration, not a decreased rate of epidermal migration, contributes to the slower epithelialization of CO2 laser-incised skin wounds.