Work-related musculoskeletal disorders in dockworkers. Systematic review and meta-analysis.

BACKGROUND: Dockworkers are exposed to physical overloads that can contribute to the development of musculoskeletal disorders, leading to functional disability and absenteeism. OBJECTIVE: to map, critically appraise, and synthesize the available evidence on the prevalence of musculoskeletal diseases associated with port occupational activities. METHODS: A comprehensive search was conducted in structured and unstructured databases in August 2023, with no date or language restriction, to identify observational studies evaluating the prevalence of musculoskeletal disorders in dockworkers' occupational activity. The risk of bias was assessed using validated tools based on the included study designs. Data from studies were pooled in meta-analyses. The certainty of the evidence was assessed using the GRADE approach. RESULTS: We identified 12 analytical cross-sectional studies involving 7821 participants in ports of five countries. Most studies (75%) had a moderate methodological quality according to the Joanna Briggs Institute tool. Considering the overall worker categories and any musculoskeletal disorders, the meta-analysis showed a prevalence of 58% (95% Confidence Interval [95% CI] 37% to 78%), with degenerative spinal diseases 42% (95% CI -0.6% to 91%) and low back pain 36% (95% CI 21% to 50%) being the most prevalent conditions. Symptoms were predominantly in foremen and stevedores. The certainty of the evidence was very low. CONCLUSIONS: Musculoskeletal disorders seem prevalent among dockworkers, mainly degenerative spinal diseases and low back pain. Studies with greater methodological consistency are still needed to validate these hypotheses and assist in decision-making for implementing preventive and informational policies in maritime port management organizations. PROSPERO registry CRD42021257677.

The pivotal role of neuronal nitric oxide synthase in the release of 6-nitrodopamine from mouse isolated vas deferens.

6-Nitrodopamine (6-ND) is released from rat and human vas deferens and is considered a major mediator of both tissues contractility. The contractions induced by 6-ND are selectively blocked by both tricyclic antidepressants and α1-adrenoceptor antagonists. Endothelial nitric oxide synthase (eNOS) is the major isoform responsible for 6-ND release in mouse isolated heart, however the origin of 6-ND in the vas deferens is unknown. Here it was investigated by LC-MS/MS the basal release of 6-ND from isolated vas deferens obtained from control, eNOS-/-, nNOS-/-, and iNOS-/- mice. In addition, it was evaluated in vitro vas deferens contractility following electric field stimulation (EFS). Basal release of 6-ND was significantly reduced in nNOS-/- mice compared to control mice, but not decreased when the vas deferens were obtained from either eNOS-/- or iNOS-/- mice. Pre-incubation of the vas deferens with tetrodotoxin (1 µM) significantly reduced the basal release of 6-ND from control, eNOS-/-, and iNOS-/- mice but had no effect on the basal release of 6-ND from nNOS-/- mice. EFS-induced frequency-dependent contractions of the vas deferens, which were significantly reduced when the tissues obtained from control, eNOS-/- and iNOS-/- mice, were pre-incubated with l-NAME, but unaltered when the vas deferens was obtained from nNOS-/- mice. In addition, the EFS-induced contractions were significantly smaller when the vas deferens were obtained from nNOS-/- mice. The results clearly demonstrate that nNOS is the main NO isoform responsible for 6-ND release in mouse vas deferens and reinforces the concept of 6-ND as a major modulator of vas deferens contractility.

6-Nitrodopamine potentiates contractions of rat isolated vas deferens induced by noradrenaline, adrenaline, dopamine and electric field stimulation.

6-Nitrodopamine (6-ND) is a novel endogenous catecholamine that is released from the rat isolated vas deferens, and has been characterized as a major modulator of the contractility of rat isolated epididymal vas deferens (RIEVD). Drugs such as tricyclic antidepressants, α1 and ß1ß2 adrenoceptor blockers, act as selective antagonists of the 6-ND receptor in the RIEVD. In the rat isolated atria, 6-ND has a potent positive chronotropic action and causes remarkable potentiation of the positive chronotropic effects induced by dopamine, noradrenaline, and adrenaline. Here, whether 6-ND interacts with the classical catecholamines in the rat isolated vas deferens was investigated. Incubation with 6-ND (0.1 and 1 nM; 30min) caused no contractions in the RIEVD but provoked significant leftward shifts in the concentration-response curves to noradrenaline, adrenaline, and dopamine. Pre-incubation of the RIEVD with 6-ND (1 nM), potentiated the contractions induced by electric-field stimulation (EFS), whereas pre-incubation with 1 nM of dopamine, noradrenaline or adrenaline, did not affect EFS-induced contractions. In tetrodotoxin (1 µM) pre-treated (30 min) RIEVD, pre-incubation with 6-ND (0.1 nM) did not cause leftward shifts in the concentration-dependent contractions induced by noradrenaline, adrenaline, or dopamine. Pre-incubation of the RIEVD with the α2A-adrenoceptor antagonist idazoxan (30 min, 10 nM) did not affect dopamine, noradrenaline, adrenaline, and EFS-induced contractions. However, when idazoxan (10 nM) and 6-ND (0.1 nM) were simultaneously pre-incubated (30 min), a significant potentiation of the EFS-induced contractions of the RIEVD was observed. 6-nitrodopamine causes remarkable potentiation of dopamine, noradrenaline, and adrenaline contractions on the RIEVD, due to activation of adrenergic terminals, possibly via pre-synaptic adrenoceptors.

A review of Cochrane reviews on pharmacological treatment for attention deficit hyperactivity disorder / Revisão de revisões Cochrane sobre o tratamento farmacológico para transtorno do déficit de atenção e hiperatividade

ABSTRACT. Attention deficit hyperactivity disorder (ADHD) is one of the most frequent childhood psychiatric problems. Objective: The objective of this study was to identify, synthesize the results, and critically evaluate all Cochrane systematic reviews (SRs) on the pharmacological interventions for children and adolescents (up to age 18) diagnosed with ADHD. Methods: The search was performed in the Cochrane Database of Systematic Reviews (via Wiley) in July 2020. Results: The search strategy resulted in four SRs of high methodological quality, analyzing 51 randomized clinical trials (9,013 participants). Compared to placebo, treatment with tricyclic antidepressants (TCAs) (desipramine), amphetamine, and methylphenidate showed improvement in symptoms such as difficulty concentrating, impulsivity, and hyperactivity in the short term (up to 6 months). There was an increase in the occurrence of adverse events, such as reduced appetite, difficulty sleeping, and abdominal pain. Insufficient evidence was found to support the effects of supplementation with polyunsaturated fatty acids. Conclusions: The use of TCAs, amphetamine, and methylphenidate in children and adolescents with ADHD seems to present positive effects and higher rates of minor adverse events when compared to placebo.

RESUMO. Déficit de atenção e hiperatividade (TDAH) é uma das mais frequentes condições psiquiátricas da infância. Objetivo: O objetivo deste artigo foi identificar, sintetizar os resultados e avaliar criticamente todas as revisões sistemáticas (RS) da Cochrane sobre as intervenções farmacológicas para crianças e adolescentes (até 18 anos de idade) diagnosticados com transtorno do déficit de atenção com hiperatividade. Métodos: A pesquisa foi realizada na base de dados Cochrane de Revisões Sistemáticas — CDSR (via Wiley) em julho de 2020. Resultados: A estratégia de busca resultou em quatro RS de alta qualidade metodológica, que analisavam 51 ensaios clínicos randomizados (9.013 participantes). Comparado ao placebo, o tratamento com antidepressivos tricíclicos (desipramina), anfetamina e metilfenidato apresentou melhora nos sintomas, como dificuldade de concentração, impulsividade e hiperatividade no curto prazo (até seis meses). Houve aumento na ocorr≖ncia de eventos adversos, como redução do apetite, dificuldade para dormir e dor abdominal. Foram encontradas evid≖ncias insuficientes para apoiar os efeitos da suplementação com ácidos graxos poli-insaturados. Conclusões: Com base nos resultados de revisões sistemáticas Cochrane, o uso de antidepressivos tricíclicos, anfetamina e metilfenidato em crianças e adolescentes com TDAH parece apresentar efeitos positivos e taxas mais elevadas de eventos adversos menores quando comparado ao placebo. Dado o alto risco de viés nos estudos primários incluídos nessas RS, ainda são necessários novos ensaios clínicos randomizados com rigor metodológico para apoiar esses achados.

Quantification of 6-nitrodopamine in Krebs-Henseleit's solution by LC-MS/MS for the assessment of its basal release from Chelonoidis carbonaria aortae in vitro.

In this study, the development and validation of a method for quantification of 6-nitrodopamine in Krebs-Henseleit's solution by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) with positive ion electrospray ionization is described. Aortic rings taken from tortoise were either denuded or left with endothelium intact (15 mm, N = 6) and were incubated for 30 min in 5 mL Krebs-Henseleit's solution in an organ bath. Solid phase extraction (SPE) was performed for aliquots of 1 mL of the supernatant. The separation of 6-nitrodopamine was obtained on a 150 mm × 3 mm Shim-pack GIST-HP C18 column, using 75% of mobile phase A consisted of deionized water with 0.1% formic acid (v/v) and 25% of mobile phase B consisted of acetonitrile/deionized water (50/50, v/v) + 0.1% formic acid at a flow rate of 350 µL/min in an isocratic mode. The method was linear over the concentration range of 0.1-20 ng/mL. The method was sensitive, precise and accurate for the assessment of the basal release of 6-nitrodopamine from Chelonoidis carbonaria aortae in vitro. The mean ± SEM concentrations of 6-nitrodopamine released from endothelium-intact and endothelium-denuded aortae were 0.44 ± 0.06 ng/mL and 0.18 ± 0.05 ng/mL, respectively. These results indicate that tortoise's aortae display a basal endothelium-derived 6-nitrodopamine release.

A review of Cochrane reviews on pharmacological treatment for attention deficit hyperactivity disorder.

Attention deficit hyperactivity disorder (ADHD) is one of the most frequent childhood psychiatric problems. Objective: The objective of this study was to identify, synthesize the results, and critically evaluate all Cochrane systematic reviews (SRs) on the pharmacological interventions for children and adolescents (up to age 18) diagnosed with ADHD. Methods: The search was performed in the Cochrane Database of Systematic Reviews (via Wiley) in July 2020. Results: The search strategy resulted in four SRs of high methodological quality, analyzing 51 randomized clinical trials (9,013 participants). Compared to placebo, treatment with tricyclic antidepressants (TCAs) (desipramine), amphetamine, and methylphenidate showed improvement in symptoms such as difficulty concentrating, impulsivity, and hyperactivity in the short term (up to 6 months). There was an increase in the occurrence of adverse events, such as reduced appetite, difficulty sleeping, and abdominal pain. Insufficient evidence was found to support the effects of supplementation with polyunsaturated fatty acids. Conclusions: The use of TCAs, amphetamine, and methylphenidate in children and adolescents with ADHD seems to present positive effects and higher rates of minor adverse events when compared to placebo.

Déficit de atenção e hiperatividade (TDAH) é uma das mais frequentes condições psiquiátricas da infância. Objetivo: O objetivo deste artigo foi identificar, sintetizar os resultados e avaliar criticamente todas as revisões sistemáticas (RS) da Cochrane sobre as intervenções farmacológicas para crianças e adolescentes (até 18 anos de idade) diagnosticados com transtorno do déficit de atenção com hiperatividade. Métodos: A pesquisa foi realizada na base de dados Cochrane de Revisões Sistemáticas ­ CDSR (via Wiley) em julho de 2020. Resultados: A estratégia de busca resultou em quatro RS de alta qualidade metodológica, que analisavam 51 ensaios clínicos randomizados (9.013 participantes). Comparado ao placebo, o tratamento com antidepressivos tricíclicos (desipramina), anfetamina e metilfenidato apresentou melhora nos sintomas, como dificuldade de concentração, impulsividade e hiperatividade no curto prazo (até seis meses). Houve aumento na ocorr≖ncia de eventos adversos, como redução do apetite, dificuldade para dormir e dor abdominal. Foram encontradas evid≖ncias insuficientes para apoiar os efeitos da suplementação com ácidos graxos poli-insaturados. Conclusões: Com base nos resultados de revisões sistemáticas Cochrane, o uso de antidepressivos tricíclicos, anfetamina e metilfenidato em crianças e adolescentes com TDAH parece apresentar efeitos positivos e taxas mais elevadas de eventos adversos menores quando comparado ao placebo. Dado o alto risco de viés nos estudos primários incluídos nessas RS, ainda são necessários novos ensaios clínicos randomizados com rigor metodológico para apoiar esses achados.

Determination of dopamine, noradrenaline, and adrenaline in Krebs-Henseleit solution by liquid chromatography coupled with tandem mass spectrometry and measurement of their basal release from Chelonoidis carbonaria aortae in vitro.

This study presented for the first time the development and validation of a sensitive method for quantification of dopamine, noradrenaline, and adrenaline in Krebs-Henseleit solution by LC-tandem mass spectrometry. Aliquots of 2.0 mL calibrators, quality controls, and samples of Krebs-Henseleit solution incubated with tortoise's aortic ring for 30 min were extracted by solid-phase extraction. Catecholamine separation was achieved on a 100 × 4.6 mm LiChrospher RP-8 column and the quantification was performed by a mass spectrometer equipped with an electrospray interface operating in positive ion mode. The run time was 4 min and the calibration curve was linear over the range of 0.1-20.0 ng/mL. The method was applied to the measurement of basal release of dopamine, noradrenaline, and adrenaline from the tortoise Chelonoidis carbonaria aortae in vitro. One aortic ring (30 mm) per tortoise (n = 5) was incubated for 30 min in a 5 mL organ bath filled with Krebs-Henseleit solution. The method demonstrated sensitivity, precision, and accuracy enough for its application in the measurement of basal release of these catecholamines from C. carbonaria aortic rings in vitro. The mean (standard deviation) concentrations of dopamine, noradrenaline, and adrenaline were 3.48 (2.55) ng/mL, 1.40 (0.57) ng/mL, and 1.87 (1.09) ng/mL, respectively.

Estudo da prevalência de irrupção dos terceiros molares por meio de radiografias panorâmicas digitais / Prevalence of eruption of the third molars using digital panoramic radiographs

Objetivo ­ Identificar a situação cronológica de irrupção dos terceiros molares por meio de radiografias panorâmicas digitais, e correlacioná-la com a faixa etária e a presença ou não do primeiro molar. Métodos ­ Analisou-se a prevalência de irrupção dos terceiros molares superiores e inferiores em radiografias panorâmicas digitais de 1341 pacientes de ambos os gêneros,com faixa etária de 17 a 23 anos, e a presença ou não dos primeiros molares. Resultados ­ Não houve distinção por gênero entre os pacientes. Pacientes entre 17 e 21 anos tiveram maiores possibilidades de irrupção dos terceiros molares e de 21 a 23 anos, a irrupção tornou-se mais rara, ou seja, praticamente nula, descartando-se assim a possibilidade de sua irrupção. A presença ou não dos primeiros molares alteraram os resultados quanto a irrupção dos terceiros molares. Quando ausente o primeiro molar, observou-se um maior índice de irrupção. Conclusões ­ Houve diferença estatística (p>0,0004) na comparação de irrupção dos terceiros molares em relação à presença ou ausência do primeiro molar. A presença do primeiro molar interfere na incidência de irrupção do terceiro molar do mesmo lado. Pacientes, independente da idade, que apresentaram ausência do primeiro molar, apresentaram menores índices de não irrupção do terceiro molar do mesmo lado.

Objective ­ To identify the chronological situation of eruption of third molars and correlates it with the band age and the presence or absence of the first molar. Methods ­ It was analyzed the prevalence of eruption of upper and lower third molars in digital panoramic radiographs 1341 patients aged 17-23 years and the presence or absence of first molars. Results ­ There was no difference by gender among patients. Patients between 17 and 21 years had higher chances of eruption of third molars and 21-23 years, the outbreak is rare or practically zero, thus ruling out the possibility of its emergence, and presence or absence of first molars alter results as the eruption of third molars, where there was a major outbreak index. Conclusions ­ IWas no statistical difference (p> 0.0004) in the third molar eruption of comparison for the presence or absence of the first molar. It presence interfere in the incidence of eruption of third molar on the same side. Patients independently of age, who presented absence of the first molar, had lower rates of non eruption of the third molar on the same side

Microhardness in pressing layers of prefabricated modified acrylic resin teeth / Microdureza nas camadas de prensagem de dentes pré-fabricados em resina acrílica modificada

OBJECTIVE: The aim of this study was to evaluate the microhardness in pressing layers of prefabricated modified acrylic resin teeth. METHODS: Lower first molar teeth with two (Biotone(r) IPN and Bioform(r)) or three pressing layers (Artiplus(r), Trilux(r) Eurovipi, and Natusdent(r)) were hemisected in a bucco-lingual plane and embedded in a self-curing acrylic resin (n =10). Specimens were then ground flat and polished using 400, 600 and 1200 aluminium oxide paper in a rotatory polisher. In each pressing layer, microhardness was measured using a Knoop indenter in three different locations spaced 300 µm apart under a 10-g load, applied for 5 sec. RESULTS: Analysis of variance and Tukey's tests demonstrated that there was no difference in microhardness in the first layer of the teeth analyzed (p = 0.355), whereas in the second layer, the brand Artiplus(r) showed higher values when compared to the brand Natusdent(r) (p = 0.018). For the third layer, the brands Artiplus(r) and Trilux(r) Eurovipi revealed higher microhardness when compared to Natusdent(r) teeth (p < 0.001). CONCLUSION: For the outer most superficial layer of the artificial teeth, the microhardness of the different brands was similar, while differences were noted for the second and third layers among the artificial teeth, with Artiplus(r) teeth showing higher microhardness than Natusdent(r). .

OBJETIVO: Avaliar a microdureza nas camadas de prensagem de dentes fabricados em resina acrílica modificada. MÉTODOS: Primeiros molares inferiores pré-fabricados com duas (Biotone(r) IPN e Bioform(r)) ou três camadas de prensagem (Artiplus(r), Trilux(r) Eurovipi e Natusdent(r)), foram hemisseccionados no sentido vestíbulo-lingual e embutidos em resina acrílica autopolimerizável (n = 10). Os espécimes foram, então, planificados e polidos com lixas de óxido de alumínio nas granulações 400, 600 e 1200, em politriz giratória. Em cada camada de prensagem, a microdureza foi mensurada utilizando indentador Knoop em três diferentes localizações, espaçadas em 300 µm, sob carga de 10 g, aplicada por 5 s. RESULTADOS: Análises de variância e testes de Tukey demonstraram que os dentes avaliados não apresentaram diferenças de microdureza na primeira camada (p = 0,355), enquanto na segunda, os dentes da marca Artiplus(r) revelaram valores superiores em relação aos dentes da marca Natusdent(r) (p = 0,018). Na terceira camada, os dentes da marca Artiplus(r) e Trilux(r) Eurovipi apresentaram microdureza superior àquela verificada para os dentes Natusdent(r) (p < 0,001). CONCLUSÃO: Na camada externa, mais superficial, a microdureza dos dentes artificiais foi semelhante nas diferentes marcas. Apenas nas segunda e terceira camadas houve diferenças entre as marcas de dentes artificiais, sendo que os dentes da Artiplus(r) apresentaram microdureza superior aos dentes Natusdent(r). .

Quantification of cyproheptadine in human plasma by high-performance liquid chromatography coupled to electrospray tandem mass spectrometry in a bioequivalence study.

A rapid, sensitive and specific method to quantify cyproheptadine in human plasma using amitriptyline as the internal standard (IS) is described. The analyte and the IS were extracted from plasma by liquid-liquid extraction using a diethyl-ether/dichloromethane (70/30; v/v) solvent. After removing and drying the organic phase, the extracts were reconstituted with a fixed volume of acetonitrile/water (50/50 v/v)+0.1% of acetic acid. The extracts were analyzed by high performance liquid chromatography coupled to electrospray tandem mass spectrometry (LC-MS/MS). Chromatography was performed isocratically using an Alltech Prevail C18 5 µm analytical column, (150 mm x 4.6 mm I.D.). The method had a chromatographic run time of 4 min and a linear calibration curve ranging from 0.05 to 10 ng/mL (r2 > 0.99). The limit of quantification was 0.05 ng/mL. This HPLC/MS/MS procedure was used to assess the bioequivalence of cyproheptadine in two cyproheptadine + cobamamide (4 mg + 1 mg) tablet formulations (Cobactin® [cyproheptadine + cobamamide] test formulation supplied from Zambon Laboratórios Farmacêuticos Ltda. and Cobavital® from Solvay Farma (standard reference formulation)). A single 4 mg + 1 mg [cyproheptadine + cobamamide] dose of each formulation was administered to healthy volunteers. The study was conducted using an open, randomized, two-period crossover design with a 1-week washout interval. Since the 90% CI for Cmax and AUCs ratios were all within the 80-125% bioequivalence limit proposed by the US Food and Drug Administration, it was concluded that the cyproheptadine test formulation (Cobactin®) is bioequivalent to the Cobavital® formulation for both the rate and the extent of absorption of cyproheptadine.

Comparative bioavailability of betahistine tablet formulations administered in healthy subjects.

OBJECTIVE: To assess the comparative bioavailability of two formulations (16 mg tablet) of betahistine (CAS 5579-84-0) in healthy volunteers of both sexes. METHODS: The study was conducted using an open, randomized, two-period crossover design with a 1-week washout interval. Plasma samples were obtained for up to 36 h post dose. Plasma 2-pyridylacetic acid concentrations were analyzed by liquid chromatography coupled with tandem mass spectrometry (LC-MS-MS) with positive ion electrospray ionization using multiple reaction monitoring (MRM). From the 2-pyridylacetic acid plasma concentration vs. time curves, the following pharmacokinetic parameters were obtained for AUCIast and Cmax. RESULTS: The limit of quantification was 4 ng/mL for plasma 2-pyridylacetic acid analysis. The geometric mean and 90% confidence interval (CI) of test/reference percent ratios were: 98.94% (92.21%-106.16%) for Cmax, 95.42% (91.74%-99.25%) for AUClast. CONCLUSION: Since the 90% CI for Cmax and AUCs ratios were all within the 80-125% interval proposed by the US Food and Drug Administration Agency, it was concluded that the test formulation is bioequivalent to the reference for both the rate and the extent of absorption.

Pharmacokinetics and pharmacodynamics of a nitric oxide-releasing derivative of enalapril in male beagles.

1. Pharmacological compounds that release nitric oxide (NO) have been useful tools in the evaluation of the broad role of NO in physiopathology and therapeutics. The present study compared the pharmacokinetics and pharmacodynamics of enalapril and an NO-releasing enalapril molecule (NCX899) in conscious male beagles. The effects of both enalapril and NCX899 in the arterial hypertension and bradycardia induced by acute NO inhibition in anaesthetized dogs were also investigated. 2. Dogs received either NCX899 (4 micromol/kg, i.v.) or enalapril (4 micromol/kg, i.v.), after which plasma concentrations of the analytes and metabolites were quantified by liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). 3. In the NCX899 group, the area under the time-course curve (AUC(0-24h)) was 29.18 +/- 4.72, 229.37 +/- 51.32 and 5159.23 +/- 514.88 microg.h/L for the analytes nitro-enalapril, enalapril and enalaprilat, respectively. In the enalapril group, the AUC(0-24h) was 704.53 +/- 158.86 and 4149.27 +/- 847.30 microg.h/L for the analytes enalapril and enalaprilat, respectively. Statistical analysis of data from both groups showed a significant difference for the analyte enalapril, but not for enalaprilat. Moreover, NCX899 and enalapril were equally effective in inhibiting the activity of serum angiotensin-converting enzyme. 4. In anaesthetized dogs, i.v. administration of the NO synthase (NOS) inhibitor N(G)-nitro-l-arginine methyl ester (l-NAME; 0.1-10 mg/kg) significantly elevated arterial blood pressure, with concomitant bradycardia. The compound NCX899 significantly attenuated both arterial hypertension and bradycardia, whereas enalapril had no significant effect. 5. In conclusion, the present results showed that the NO-releasing derivative of enalapril NCX899 presents a pharmacokinetic/pharmacodynamic relationship similar to its parent compound enalapril. Moreover, NCX899 (but not enalapril) was effective in protecting against the cardiovascular changes induced by acute NOS inhibition.

Comparative bioavailability study with two gemfibrozil tablet formulations in healthy volunteers.

OBJECTIVE: To assess the bioequivalence of gemfibrozil (CAS 25812-30-0) 900 mg tablet formulation from EMS Farmaceutica as test formulation versus a 900 mg tablet formulation as reference in 36 healthy volunteers of both sexes. METHODS: The study was conducted using an open, randomized, two-period crossover design with a 1-week washout interval. Plasma samples were obtained over a 24-h period. Plasma gemfibrozil concentrations were analyzed by liquid chromatography coupled to tandem mass spectrometry (LC-MS-MS) with negative ion electrospray ionization using multiple reaction monitoring (MRM). From the gemfibrozil plasma concentration vs time curves, the following pharmacokinetic parameters were obtained: AUClast, AUC(0-inf) and Cmax. RESULTS: The limit of quantification was 0.05 microg/mL for plasma gemfibrozil analysis. The geometric mean and respective 90% confidence interval (CI) of Test/Reference percent ratios were 90.29 (81.39-100.17) for Cmax, 96.26 (90.33-102.59) for AUClast, 96.04 (90.21-102.23) for AUC(0-24 h) and 96.62 (90.82-102.78) for AUC(0-infinity). CONCLUSION: Since the 90% CI for AUClast, AUC(0-inf) and Cmax, ratios were within the 80-125% interval proposed by the U.S. FDA, it was concluded that gemfibrozil 900 mg tablet (test formulation) was bioequivalent to the 900 mg tablet reference formulation for both rate and extent of absorption.

Quantification of carvedilol in human plasma by high-performance liquid chromatography coupled to electrospray tandem mass spectrometry: application to bioequivalence study.

A rapid, sensitive and specific method to quantify carvedilol in human plasma using metoprolol as the internal standard (IS) is described. The analyte and the IS were extracted from plasma by liquid-liquid extraction using a diethyl-ether solvent. After removed and dried the organic phase, the extracts were reconstituted with a fixed volume of acetonitrile-water (50/50; v/v). The extracts were analyzed by a high performance liquid chromatography coupled to electrospray tandem mass spectrometry (HPLC-MS/MS). Chromatography was performed isocratically on Alltech Prevail C18 5 microm analytical column, (150 mm x 4.6 mm i.d.). The method had a chromatographic run time of 3.5 min and a linear calibration curve over the range 0.1-200 ng ml(-1) (r2>0.997992). The limit of quantification was 0.1 ng ml(-1). This HPLC-MS/MS procedure was used to assess the bioequivalence of two carvedilol 25 mg tablet formulations (carvedilol test formulation from Laboratórios Biosintética Ltda and Coreg from Roche Químicos e Farmacêuticos S.A standard reference formulation). A single 25 mg dose of each formulation was administered to healthy volunteers. The study was conducted using an open, randomized, two-period crossover design with a 2-week wash-out interval. Since the 90% CI for C(max) and AUCs ratios were all inside the 80-125% interval proposed by the US Food and Drug Administration Agency, it was concluded that carvedilol formulation elaborated by Laboratórios Biosintética Ltda is bioequivalent to Coreg formulation for both the rate and the extent of absorption.

Ticlopidine quantification in human plasma by high-performance liquid chromatography coupled to electrospray tandem mass spectrometry. Application to bioequivalence study.

A rapid, sensitive and specific method to quantify ticlopidine in human plasma using clopidogrel as the internal standard (IS) is described. The analyte and the IS were extracted from acidified plasma by liquid-liquid extraction using diethyl ether-hexane (80 : 20, v/v). The extracts were analyzed by high-performance liquid chromatography coupled to electrospray tandem mass spectrometry (HPLC/MS/MS). Chromatography was performed isocratically on a Jones Genesis C(8) 4 microm analytical column (150 x 4.1 mm i.d.). The method had a chromatographic run time of 3.0 min and a linear calibration curve over the range 1.0-1000 ng ml(-1) (r(2) > 0.999427). The limit of quantification was 1.0 ng ml(-1). This HPLC/MS/MS procedure was used to assess the bioequivalence of two ticlopidine 250 mg tablet formulations (ticlopidine test formulation from Apotex do Brasil, Brazil, and Ticlid from Sanofi-Synthelabo, standard reference formulation). A single 250 mg dose of each formulation was administered to healthy volunteers. The study was conducted using an open, randomized, two-period crossover design with a 2 week washout interval. Since the 90% confidence interval for C(max) and area under the curve ratios were all inside the 80-125% interval proposed by the US Food and Drug Administration, it was concluded that ticlopidine formulation from Apotex do Brasil is bioequivalent to Ticlid formulation with respect to both the rate and the extent of absorption.

Biodisponibilidade comparativa de duas formulações de sertralina em voluntários humanos sadios após a administração de uma única dose / Comparative bioavailability of two sertraline formulations in healthy human volunteers after a single dose administration

Objetivo: Comparar a biodisponibilidade de duas formulações do comprimido de 50 mg de sertralína (Sertralina da Eurofarma Laboratórios Ltda., Brasil, como formulação teste, e ZoloC dos Laboratórios Pfizer Ltda., Brasil, como formulação de referência) em 24 voluntários sadios de ambos os sexos. Material e métodos: O estudo foi aberto, cruzado e randomizado com dois períodos e período entre as doses de duas semanas. Amostras do plasma foram obtidas em um intervalo de 96 horas. As concentrações de sertralína foram analisadas por cromatografia em fase líquida de alta eficiência, acoplada a espectrometria de massa (LC-MS-MS) com ionização positiva. Das curvas de concentração de sertralína no plasma vs. tempo foram obtidos os seguintes parâmetros farmaco- cinéticos: ASC(last)- ASC, e C(max) Resultados: A proporção porcentual individual da médía geométrica de Sertralina/Zoloffl 50 mg foi de 98,9(por cento) para ASC(last) 99,0(por cento) para ASC e 93,7(por cento) para C(max). Os intervalos de confiança de 90(por cento) (IC90( por cento)) foram de 91,4 porcento- 107,0( porcento) 89,7 (porcento)-109,4(por cento) e 84,5(por cento)-104,0(porcento), respectivamente. Conclusão: Como o 1C90(porcento) para Cmax ASC(last) e ASC(oo) estava dentro do intervalo de 80porcento- 125porcento proposto pela Agência Regulatória Americana FDA, concluiu-se que o comprimido de Sertralina 50 mg da Eurofarma Laboratórios Ltda. é bioequivalente ao comprimido Zoloft 50 mg, de acordo com o grau e a extensão de sua absorção.