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1.
Animals (Basel) ; 14(13)2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38997968

RESUMO

This study aimed to determine whether the eggs of laying hens fed caffeine contain this compound and its primary metabolites (theophylline, theobromine, and paraxanthine). Laying hens were distributed into four experimental groups fed rations containing 0 (control), 150, 300, or 450 µg/g of caffeine. For residual analysis, six eggs per group were collected after 4, 8, and 12 weeks. The concentrations of caffeine, theophylline, theobromine, and paraxanthine were determined in the white and yolk of each egg by a high-performance liquid chromatography with photodiode array detector (HPLC-PDA) method. All four compounds were detected in the white and yolk of eggs produced by hens fed caffeine, but their levels in the egg white were approximately twice those in the yolk. The major metabolite found in eggs was theophylline (57.5% of caffeine metabolites in the egg white and 58.5% in the yolk), followed by theobromine (39.9% in the egg white and 41.5% in the yolk), and paraxanthine (2.64% in the egg white and non-detected in the yolk). In summary, caffeine and its metabolites, theophylline, theobromine, and paraxanthine, are transferred to the chicken eggs.

2.
Talanta ; 275: 126154, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38703477

RESUMO

Additive manufacturing is a technique that allows the construction of prototypes and has evolved a lot in the last 20 years, innovating industrial fabrication processes in several areas. In chemistry, additive manufacturing has been used in several functionalities, such as microfluidic analytical devices, energy storage devices, and electrochemical sensors. Theophylline and paracetamol are important pharmaceutical drugs where overdosing can cause adverse effects, such as tachycardia, seizures, and even renal failure. Therefore, this paper aims at the development of miniaturized electrochemical sensors using 3D printing and polylactic acid-based conductive carbon black commercial filament for theophylline and paracetamol detection. Electrochemical characterizations of the proposed sensor were performed to prove the functionality of the device. Morphological characterizations were carried out, in which chemical treatment could change the surface structure, causing the improvement of the analytical signal. Thus, the detection of theophylline at a linear range of 5.00-150 µmol L-1 with a limit of detection of 1.2 µmol L-1 was attained, and the detection of paracetamol at a linear range of 1.00-200 µmol L-1 with a limit of detection of 0.370 µmol L-1 was obtained, demonstrating the proposed sensor effectively detected pharmaceutical drugs.


Assuntos
Acetaminofen , Técnicas Eletroquímicas , Poliésteres , Fuligem , Teofilina , Acetaminofen/análise , Fuligem/química , Técnicas Eletroquímicas/métodos , Teofilina/análise , Poliésteres/química , Limite de Detecção , Impressão Tridimensional , Miniaturização
3.
Acta Crystallogr C Struct Chem ; 80(Pt 6): 190-199, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38712545

RESUMO

The receptor ability of diethyl N,N'-(1,3-phenylene)dicarbamate (1) to form host-guest complexes with theophylline (TEO) and caffeine (CAF) by mechanochemistry was evaluated. The formation of the 1-TEO complex (C12H16N2O4·C7H8N4O2) was preferred and involves the conformational change of one of the ethyl carbamate groups of 1 from the endo conformation to the exo conformation to allow the formation of intermolecular interactions. The formation of an N-H...O=C hydrogen bond between 1 and TEO triggers the conformational change of 1. CAF molecules are unable to form an N-H...O=C hydrogen bond with 1, making the conformational change and, therefore, the formation of the complex impossible. Conformational change and selective binding were monitored by IR spectroscopy, solid-state 13C nuclear magnetic resonance and single-crystal X-ray diffraction. The 1-TEO complex was characterized by IR spectroscopy, solid-state 13C nuclear magnetic resonance, powder X-ray diffraction and single-crystal X-ray diffraction.

4.
Int J Mol Sci ; 24(6)2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36982957

RESUMO

Theophylline is a drug commonly used to treat asthma due to its anti-inflammatory and bronchodilatory properties. Testosterone (TES) has been suggested to reduce the severity of asthma symptoms. This condition affects boys more than girls in childhood, and this ratio reverses at puberty. We reported that guinea pig tracheal tissue chronic exposure to TES increases the expression of ß2-adrenoreceptors and enhances salbutamol-induced K+ currents (IK+). Herein, we investigated whether the upregulation of K+ channels can enhance the relaxation response to methylxanthines, including theophylline. Chronic incubation of guinea pig tracheas with TES (40 nM, 48 h) enhanced the relaxation induced by caffeine, isobutylmethylxanthine, and theophylline, an effect that was abolished by tetraethylammonium. In tracheal myocytes, chronic incubation with TES increased theophylline-induced IK+; flutamide reversed this effect. The increase in IK+ was blocked by 4-aminopyridine by ~82%, whereas iberiotoxin reduced IK+ by ~17%. Immunofluorescence studies showed that chronic TES exposure increased the expression of KV1.2 and KV1.5 in airway smooth muscle (ASM). In conclusion, chronic exposure to TES in guinea pig ASM promotes upregulation of KV1.2 and KV1.5 and enhances theophylline relaxation response. Therefore, gender should be considered when prescribing methylxanthines, as teenage boys and males are likely to respond better than females.


Assuntos
Asma , Teofilina , Masculino , Feminino , Cobaias , Animais , Teofilina/farmacologia , Testosterona/farmacologia , Relaxamento Muscular , Maturidade Sexual , Músculo Liso , Traqueia
5.
Int J Mol Sci ; 23(8)2022 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-35456985

RESUMO

Theophylline (3-methyxanthine) is a historically prominent drug used to treat respiratory diseases, alone or in combination with other drugs. The rapid onset of the COVID-19 pandemic urged the development of effective pharmacological treatments to directly attack the development of new variants of the SARS-CoV-2 virus and possess a therapeutical battery of compounds that could improve the current management of the disease worldwide. In this context, theophylline, through bronchodilatory, immunomodulatory, and potentially antiviral mechanisms, is an interesting proposal as an adjuvant in the treatment of COVID-19 patients. Nevertheless, it is essential to understand how this compound could behave against such a disease, not only at a pharmacodynamic but also at a pharmacokinetic level. In this sense, the quickest approach in drug discovery is through different computational methods, either from network pharmacology or from quantitative systems pharmacology approaches. In the present review, we explore the possibility of using theophylline in the treatment of COVID-19 patients since it seems to be a relevant candidate by aiming at several immunological targets involved in the pathophysiology of the disease. Theophylline down-regulates the inflammatory processes activated by SARS-CoV-2 through various mechanisms, and herein, they are discussed by reviewing computational simulation studies and their different applications and effects.


Assuntos
Tratamento Farmacológico da COVID-19 , Antivirais/farmacocinética , Antivirais/uso terapêutico , Humanos , Simulação de Acoplamento Molecular , Pandemias , SARS-CoV-2 , Teofilina/farmacologia , Teofilina/uso terapêutico
6.
Braz. J. Pharm. Sci. (Online) ; 58: e20804, 2022. tab, graf
Artigo em Inglês | LILACS-Express | LILACS | ID: biblio-1420391

RESUMO

Abstract The purpose of this study was to evaluate the antifibrotic and antioxidant roles of theophylline (Theo), a bioactive compound, in bleomycin (BLM)-induced pulmonary fibrosis in Wistar albino rats. Assigned into 4 groups were 32 Wistar albino rats, comprising the control group (administered 0.9% isotonic saline), BLM group (treated with BLM at a dose of 2.5 mg/kg), BLM+Theo group (treated with Theo at a dose of 75 mg/kg + BLM at a dose of 2.5 mg/kg), and Theo group (treated with Theo at a dose of 75 mg/kg). In the BLM group, a significant decrease was observed in the catalase and glutathione peroxidase enzyme activities, and reduced glutathione (GSH) (p < 0.05, p< 0.05, p< 0.001, respectively), while the malondialdehyde (MDA) levels (p< 0.001) were significantly elevated when compared to the control group. However, the MDA levels in the BLM+Theo group were also significantly higher than in the control group (p< 0.01). Similarly, the GSH levels were significantly higher in the BLM+Theo group than in the BLM group (p< 0.05). The results indicated that Theo reduced the BLM-induced activation of nuclear factor-kappaB (NF-κB) and decreased interleukin-6 (IL-6) levels, together with significant amelioration of the immunohistochemical and histopathological architecture in the lung tissues. It was concluded that the administration of Theo had a positive effect on the GSH level, and activation of NF-κB and IL-6 expression, which were significant proinflammatory markers in the BLM-treated rats.

7.
Mol Pharm ; 18(9): 3578-3587, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34428059

RESUMO

While theophylline has been extensively studied with multiple polymorphs discovered, there is still currently no conclusive structure for the metastable theophylline form III. In this present work, by combining more widely used techniques such as X-ray diffraction and thermogravimetric analysis with more emerging techniques like low-frequency Raman and terahertz time-domain spectroscopy, to analyze the structure and dynamics of a crystalline system, it was possible to provide further evidence that the form III structure has a theophylline monohydrate structure with the water molecules removed. Solid-state density functional theory simulations were paramount in proving that this proposed structure is correct and explain how vibrational modes within the crystal structures feature and govern polymorphic transitions and the metastable form III. Through the insight provided by both simulated and experimental results, it was possible to decisively conclude the elusive crystal structure of theophylline form III. It was also shown that the correct space group for theophylline monohydrate is not P21/n but, in fact, Pc.


Assuntos
Teofilina/química , Química Farmacêutica/métodos , Estabilidade de Medicamentos , Análise Espectral Raman , Espectroscopia Terahertz , Termogravimetria , Vibração , Difração de Raios X
9.
Rev. bras. anestesiol ; Rev. bras. anestesiol;70(6): 682-685, Nov.-Dec. 2020. tab
Artigo em Inglês, Português | LILACS | ID: biblio-1155770

RESUMO

Abstract Myotonic dystrophy type-1 (Steinert disease) is an autosomal dominant, progressive multisystem disease in which myotonic crisis can be triggered by several factors including pain, emotional stress, hypothermia, shivering, and mechanical or electrical stimulation. In this report, dexmedetomidine-based general anesthesia, in combination with a thoracic epidural for laparoscopic cholecystectomy in a patient with Steinert disease, is presented. An Aintree intubation catheter with the guidance of a fiberoptic bronchoscope was used for intubation to avoid laryngoscopy. Prolonged anesthetic effects of propofol were reversed, and recovery from anesthesia was accelerated using an intravenous infusion of theophylline.


Resumo A Distrofia Miotônica (DM) tipo-1 (Doença de Steinert) é uma doença multissistêmica progressiva autossômica dominante em que a crise miotônica pode ser desencadeada por vários fatores, incluindo dor, estresse emocional, hipotermia, tremores e estímulo mecânico ou elétrico. O presente relato descreve anestesia geral realizada com dexmedetomidina em combinação com peridural torácica para colecistectomia laparoscópica em paciente com Doença de Steinert. Para evitar laringoscopia, a intubação traqueal foi realizada utilizando cateter de intubação Aintree guiado por broncofibroscopia óptica. Os efeitos anestésicos prolongados do propofol foram revertidos e a recuperação anestésica foi acelerada pelo uso de infusão intravenosa de teofilina.


Assuntos
Humanos , Feminino , Colecistectomia Laparoscópica/métodos , Analgésicos não Narcóticos , Dexmedetomidina , Anestesia Epidural/métodos , Anestesia Geral/métodos , Distrofia Miotônica/complicações , Teofilina/administração & dosagem , Período de Recuperação da Anestesia , Propofol , Broncoscópios , Analgésicos Opioides , Hipnóticos e Sedativos , Intubação Intratraqueal/métodos , Pessoa de Meia-Idade
10.
Braz J Anesthesiol ; 70(6): 682-685, 2020.
Artigo em Português | MEDLINE | ID: mdl-33190906

RESUMO

Myotonic dystrophy type-1 (Steinert disease) is an autosomal dominant, progressive multisystem disease in which myotonic crisis can be triggered by several factors including pain, emotional stress, hypothermia, shivering, and mechanical or electrical stimulation. In this report, dexmedetomidine-based general anesthesia, in combination with a thoracic epidural for laparoscopic cholecystectomy in a patient with Steinert disease, is presented. An Aintree intubation catheter with the guidance of a fiberoptic bronchoscope was used for intubation to avoid laryngoscopy. Prolonged anesthetic effects of propofol were reversed, and recovery from anesthesia was accelerated using an intravenous infusion of theophylline.


Assuntos
Analgésicos não Narcóticos , Anestesia Epidural/métodos , Anestesia Geral/métodos , Colecistectomia Laparoscópica/métodos , Dexmedetomidina , Distrofia Miotônica/complicações , Analgésicos Opioides , Período de Recuperação da Anestesia , Broncoscópios , Feminino , Humanos , Hipnóticos e Sedativos , Intubação Intratraqueal/métodos , Pessoa de Meia-Idade , Propofol , Teofilina/administração & dosagem
11.
World Allergy Organ J ; 12(12): 100084, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31768217

RESUMO

BACKGROUND: In April 2017 the Mexican Asthma Guidelines (GUIMA) were published. Before the launch, physicians' knowledge was explored related to key issues of the guideline. METHODS: A SurveyMonkey® survey was sent out to board-certified physicians of 5 medical specialties treating asthma. Replies were analyzed per specialty against the GUIMA evidence-based recommendations. We present the treatment part here. RESULTS: A total of 364 allergists (ALLERG), 161 pulmonologists (PULM), 34 ENTs, 239 pediatricians (PED) and 62 general practitioners (GPs) replied to the survey and 247-83-14-135-37 respectively finished it. Spirometry is not routinely indicated when asthma is very probable by ALLERG 54%, PULM 47%, ENT 39%, PED 65%, GP 64%. A fictitious case proposed to the physicians with intermittent asthma was erroneously treated with ICS by ALLERG 9%, PULM 11%, ENT 28%, PED 10%, GP 11%. The mild persistent case received mistakenly ICS-LABA by ALLERG 25%, PULM 26%, ENT 33%, PED 27%, GP 23%. The first-line option for moderate persistent asthma was ICS(median dose) instead of ICS(low)+LABA for ALLERG 29%, PULM 25%, ENT 17%, PED 27%, GP 23% and in severe asthma maintenance treatment PULM20%, ALLERG-ENT-PED-GP 22-34% failed to indicate LABA. Concerning the guidelines' recommendation to use one inhaler for maintenance & rescue in moderate-to-severe asthma, PULM45%, ALLERG-ENT-PED-GP 56-80% (p < 0.00001), erroneously indicated ICS-salmeterol could be used, instead of ICS-formoterol. Oral ß2 or theophylline are no longer recommended, but PULM 37% and ALLERG-ENT-PED-GP 42-62% (p < 0.01) still indicate their use. In severe asthma 61-73% of physicians consider adding LTRA to the treatment; only PULM38%, OTHERS12-25% consider adding tiotropium (p < 0.001) and 3-17% consider adding omalizumab, both guideline recommended add-ons. As for asthma in pregnancy, most surveyed are not aware budesonide is the 1st line option ICS. Finally, 81-97% of the group-members recognized allergen immunotherapy, as a viable add-on, in line with GINA/GEMA/GUIMA recommendations. CONCLUSIONS: An online survey could detect knowledge-gaps related to asthma treatment. Interestingly, surveyed physicians tended to over-treat the milder asthma cases, thus clearly leaving room for cost-savings. Caution should be taken in the promotion of the SMART (single-maintenance-and-reliever-treatment) approach, which can only be done with ICS-formoterol. Many physicians opt for other combinations not apt for this approach. Among all surveyed specialties there is ample room for improvement in mild and severe asthma management.

12.
R Soc Open Sci ; 6(3): 181738, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31032030

RESUMO

The design and synthesis of a series of theophylline derivatives containing 1,2,3-triazole moieties are presented. The corrosion inhibition activities of these new triazole-theophylline compounds were evaluated by studying the corrosion of API 5 L X52 steel in 1 M HCl medium. The results showed that an increase in the concentration of the theophylline-triazole derivatives also increases the charge transference resistance (R ct) value, enhancing inhibition efficiency and decreasing the corrosion process. The electrochemical impedance spectroscopy under static conditions studies revealed that the best inhibition efficiencies (approx. 90%) at 50 ppm are presented by the all-substituted compounds. According to the Langmuir isotherm, the compounds 4 and 5 analysed exhibit physisorption-chemisorption process, with exception of the hydrogen 3, bromo 6 and iodo 7 substituted compounds, which exhibit chemisorption process. The corrosion when submerging a steel bar in 1 M HCl was studied using SEM-EDS. This experiment showed that the corrosion process decreases considerably in the presence of 50 ppm of the organic inhibitors. Finally, the theoretical study showed a correlation between EHOMO, hardness (η), electrophilicity (W), atomic charge and the inhibition efficiency in which the iodo 7 substituted compound presents the best inhibitor behaviour.

13.
Acta Crystallogr C Struct Chem ; 73(Pt 10): 767-772, 2017 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-28978781

RESUMO

Pharmaceutical cocrystals are crystalline solids formed by an active pharmaceutical ingredient and a cocrystal former. The cocrystals 2,6-diaminopyridine (DAP)-piracetam [PIR; systematic name: 2-(2-oxopyrrolidin-1-yl)acetamide] (1/1), C5H7N3·C6H10N2O2, (I), and 2,6-diaminopyridine-theophylline (TEO; systematic name: 1,3-dimethyl-7H-purine-2,6-dione) (1/1), C5H7N3·C7H8N4O2, (II), were prepared by the solvent-assisted grinding method and were characterized by IR spectroscopy and powder X-ray diffraction. Cocrystal (I) crystallized in the orthorhombic space group Pbca and showed a 1:1 stoichiometry. The DAP and PIR molecules are linked by an N-H...O hydrogen-bond interaction. Self-assembly of PIR molecules forms a sheet of C(4) and C(7) chains. Cocrystal (II) crystallized in the monoclinic P21/c space group and also showed a 1:1 stoichiometry. The DAP and TEO molecules are connected by N-H...N and N-H...O hydrogen bonds, forming an R22(9) heterosynthon. A bidimensional supramolecular array is formed by interlinked DAP-TEO tetramers, producing a two-dimensional sheet.

14.
Braz. j. pharm. sci ; 52(1): 27-34, Jan.-Mar. 2016. tab, graf
Artigo em Inglês | LILACS | ID: lil-789087

RESUMO

ABSTRACT The present study describes the development of theophylline microcapsules by a non-solvent addition method and the effect of plasticizer addition on microencapsulation. The release was studied in distilled water and the data were analysed by various mathematical models for determining the mechanism of release. Prepared microcapsules were found to be spherical, free flowing and having more than 80% entrapped drug. The polymer - cellulose acetate phthalate and plasticizer - polyethylene glycol was considered to be affecting the properties of microcapsules including drug release (time for 50% drug release, T50). The formulation with the highest proportion of polymer and without plasticizer (F3) showed the slowest release with T50 = 4.3 h, while the formulation with lower proportion of polymer and 20% (w/w) plasticizer (F13 &14) showed the fastest release of drug with T50 values of 1.2 h and 1.3 h, respectively. The drug release from most of the formulations was found to be following Higuchi model. It is concluded from the results of the present study that cellulose acetate phthalate significantly affects the sustained release of the drug in water, whereas the addition of polyethylene glycol slightly enhances the drug release.


RESUMO O presente estudo descreve o desenvolvimento de microcápsulas de teofilina pelo método sem adição de solvente e o efeito da adição de plastificante na microencapsulação. A liberação foi estudada em água destilada e os dados foram analisados por vários modelos matemáticos para determinação do mecanismo de liberação. As microcápsulas preparadas mostraram-se esféricas, livres de corrente e com mais de 80% de fármaco encapsulado. O polímero - ftalato de acetato de celulose e o plastificante - polietileno glicol - afetaram as propriedades das microcápsulas, incluindo a liberação do fármaco (tempo para liberação de 50% do fármaco, T50). A formulação com a maior proporção de polímero e sem plastificante (F3) se mostrou como a de liberação mais lenta, com T50 = 4,3 h, enquanto as formulações com menor proporção de polímero e 20% de plastificante (m/m) (F13 &14) apresentaram a liberação mais rápida do fármaco, com T50 de 1,2 h e 1,3 h, respectivamente. A liberação do fármaco para a maioria das formulações seguiu o modelo de Higuchi. Concluiu-se, dos resultados do presente estudo, que o ftalato do acetato de celulose afeta significativamente a liberação controlada do fármaco em água, enquanto que a adição de polietileno glicol aumenta ligeiramente a liberação do fármaco.


Assuntos
Teofilina/farmacocinética , Cápsulas/administração & dosagem , Cetomacrogol/farmacocinética , Dibutilftalato/farmacocinética , Preparações Farmacêuticas , Composição de Medicamentos/métodos , Liberação Controlada de Fármacos
15.
Int Forum Allergy Rhinol ; 5 Suppl 1: S35-40, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26335835

RESUMO

BACKGROUND: Asthma is a prevalent disease characterized by chronic inflammatory changes of the airway and marked by airway hyperresponsiveness, edema, and excess mucus production. Management of the disease has focused upon reversing the early airway changes and limiting the late effects of airway remodeling. Several classes of medications are available for the effective treatment and long-term control of asthma and novel therapeutic options are in development that hold promise in improving patient outcome. METHODS: A review of updated guidelines and current literature was conducted to identify available pharmacologic treatments of asthma and determine future directions in development of novel therapeutic options. RESULTS: Inhaled corticosteroids are the most effective medications in long-term asthma control with adjunct medications such as ß2-agonists, which can provide symptomatic relief. Other classes of asthma control medications including anticholinergics, cromolyns, and leukotriene receptor modifiers can also be used to develop an effective management strategy based on asthma severity. CONCLUSION: Several classes of medications are available for the effective management of asthma. Inhaled corticosteroids play a central role in control of inflammation and several other adjuncts are available to tailor therapy to the patient's symptoms. New therapeutic options that target downstream inflammatory mediators can provide increased efficacy while limiting side effects.


Assuntos
Antiasmáticos/uso terapêutico , Asma/tratamento farmacológico , Corticosteroides/uso terapêutico , Anti-Inflamatórios/uso terapêutico , Humanos
16.
Braz. j. pharm. sci ; 49(3): 475-490, July-Sept. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-689901

RESUMO

A novel, simple, accurate and precise RP-HPLC method for simultaneous determination of levosalbutamol sulfate and theophylline has been developed and validated. Separation was achieved on a Phenomenex; C18 column (250 mm × 4.6 mm i.d., 5 µm) using methanol: 10 mM TBAHS(tetrabutyl ammonium hydrogen sulfate) (50:50, v/v) as mobile phase at flow rate of 1.0 mL.min-1. The UV detection wavelength was 274 nm. The linearity is obeyed over a concentration range of 0.5-150 µg.mL-1 with correlation coefficient of 0.999 for both the drugs. The proposed method was validated by determining accuracy, precision, stability and system suitability parameters. The method was found to be robust. Specificity of the method was determined by subjecting the drugs to various stress conditions like acid, alkali, oxidation, thermal and photolytic degradation. The method was used successfully for the simultaneous determination of levosalbutamol sulfate and theophylline in syrup dosage form.


Desenvolveu-se e validou-se método de RP-HPLC novo, simples, exato e preciso de determinação simultânea do sulfato de levossalbutamol e teofilina.. A separação foi efetuada em uma coluna Phenomenex; C18 (250 mm x 4,6 mm d.i., 5 µm) utilizando metanol: TBAHS (hidrogenossulfato de tetrabutilamônio) 10 mM (50:50, v/v) como fase móvel, com fluxo de 1,0 mL.min-1. O comprimento de onda de detecção no UV foi 274 nm. Observou-se linearidade na faixa de concentração de 0,5-150 µg mL-1, com coeficiente de correlação de 0,999 para ambos os fármacos. O método proposto foi validado determinando-se exatidão, precisão, estabilidade e parâmetros de adequação do sistema. O método mostrou-se robusto. A especificidade do método foi determinada submetendo os fármacos a várias condições de estresse, como ácido, álcali, oxidação, degradação térmica e fotolítica. O método foi usado com sucesso para a determinação simultânea do sulfato de levossalbutamol e teofilina na forma de xarope.


Assuntos
Teofilina/análise , Cromatografia Líquida de Alta Pressão/métodos , Levalbuterol/análise , Formas de Dosagem
17.
Medisan ; 16(8): 1284-1294, ago. 2012.
Artigo em Espanhol | LILACS | ID: lil-647020

RESUMO

En este estudio se evaluó el efecto del adyuvante Finlay cocleato 1 (AFCo1), aplicado 4 veces por vía intranasal en 2 niveles de dosis (50 µg y 100 µg) sobre la concentración plasmática de teofilina, administrada a las 24 horas de la última aplicación (5 mg/kg, por vía intraperitoneal) en ratas Sprague-Dawley. Se empleó como control positivo de inflamación la aplicación de 2 dosis por vía subcutánea de adyuvante completo de Freund (ACF). Las ratas que recibieron AFCo1 no mostraron cambios significativos en la concentración sérica de teofilina; mientras que las tratadas con ACF desarrollaron inflamación local asociadas a signos de toxicidad a la teofilina y elevación de las cifras de inmunoglobulina G específica, de las concentraciones plasmáticas y el tiempo de vida media de teofilina en suero, en comparación con los grupos restantes. Estos resultados indican que la inmunoestimulación inducida por AFCo1 intranasal no incrementa los parámetros farmacocinéticos ni la toxicidad de la teofilina en el modelo empleado.


The effect of the adjuvant Finlay cochleate1 (AFCo1), applied intranasally 4 times in 2 dose levels (50 µg and 100 µg) on plasma concentration of theophylline administered 24 hours after the last application (5 mg/kg intraperitoneally) in Sprague-Dawley rats was evaluated in this study. Application subcutaneously of 2 doses of Freund's complete adjuvant (FCA) was used as positive control of inflammation. Rats receiving AFCo1 had no significant changes in serum theophylline concentration, while those treated with FCA developed local inflammation associated with signs of theophylline toxicity and increased specific G immunoglobulin, plasma concentrations and serum theophylline half-life as compared with the remaining groups. These results show that intranasal AFCo1-induced immunostimulation does not increase pharmacokinetic parameters and theophylline toxicity in the model used.

18.
Braz. j. pharm. sci ; 48(2): 211-216, Apr.-June 2012. graf, tab
Artigo em Inglês | LILACS | ID: lil-643013

RESUMO

The purpose of the present study was to investigate the interaction between ketotifen fumarate and anhydrous theophylline in aqueous media of various pH (1.2 and 6.8). Using Job's continuous-variation analysis and Ardon's spectrophotomeric measurement methods, the values of the stability constants of theophylline with ketotifen were determined at a fixed temperature (37 ºC) at various pH. The stability constants, ranging between 5.66 and 9.92, were derived from Ardon's plot, indicating that comparatively stable complexes had formed as a result of an interaction between the drugs. However, following the interaction of theophylline with ketotifen, stability constants were <1 at gastric pH (1.2) and intestinal pH (6.8). Concurrent administration of ketotifen and theophylline could result in the formation of a stable complex and this is likely to reduce the therapeutic activities of both drugs.


O objetivo do presente estudo foi investigar a interação entre o fumarato de cetotifeno e a teofilina anidra em meios aquosos com vários pH (1,2 e 6,8). Utilizando a análise da variação contínua de Job e os métodos de medida espectrofotométrica de Ardon, os valores das constantes de estabilidade da teofilina com o cetotifeno foram determinados em temperatura fixa (37 oC) em vários pH. As constantes de estabilidade, variando entre 5,66 e 9,92 derivaram-se a partir do delineamento de Ardon, indicando, comparativamente, que complexos estáveis se formaram como resultado da interação entre os fármacos. Entretanto, seguindo a interação da teofilina com o cetotifeno, as constantes de estabilidade foram <1, em pH gástrico (1,2) e intestinal (8,8). A administração concomitante de cetotifeno e teofilina poderia resultar na formação de complexo estável, o que reduz a atividade terapêutica de ambos os fármacos.


Assuntos
Técnicas In Vitro/métodos , Cetotifeno/análise , Teofilina/análise , Reatividade-Estabilidade
19.
Arch. venez. pueric. pediatr ; 73(3): 26-32, dic. 2010. ilus, graf, tab
Artigo em Espanhol | LILACS | ID: lil-659148

RESUMO

El presente artículo presenta las recomendaciones de un grupo de expertos venezolanos reunidos en Caracas en Octubre de 2009 por la Sociedad Venezolana de Puericultura y Pediatría en relación al tratamiento farmacológico del asma infantil. Se presentan los objetivos del tratamiento, los medicamentos recomendados, la terapia inicial y de mantenimiento y el tipo de dispositivo para la administración de drogas por vía inhalatoria, de acuerdo a la edad del paciente.


This article presents the recommendations made by a group of Venezuelan experts during a consensus meeting held in Caracas in October, 2009, under the auspices of the Venezuelan Society of Pediatrics, on the pharmacological treatment of childhood asthma. Goals of treatment, recommended medications, initial and maintenance therapy, and devices utilized for delivery of inhaled drugs according to patient’s age are presented.

20.
RBCF, Rev. bras. ciênc. farm. (Impr.) ; RBCF, Rev. bras. ciênc. farm. (Impr.);44(1): 133-141, jan.-mar. 2008. graf, tab
Artigo em Português | LILACS | ID: lil-484376

RESUMO

Neste estudo, comprimidos de teofilina anidra foram revestidos através do processo de revestimento por compressão aplicando sistema binário pectina-HPMC. O método aplicado gerou comprimidos revestidos com características físicas adequadas aos padrões farmacopeicos. Foram avaliadas as características físicas dos comprimidos obtidos em diferentes proporções (80:20, 60:40, 50:50, 40:60, 20:80, 0:100) de pectina-HPMC respectivamente, e estabelecido o perfil de intumescimento desses sistemas nos fluidos de simulação gástrico (pH 1,2) e intestinal (pH 6,8). O método aplicado gerou a formação de comprimidos revestidos que apresentaram variação nos perfis de hidratação in vitro, entretanto, a análise estatística revelou que estas diferenças não foram significativas quando comparadas entre si. O sistema formado apresenta elevada expectativa sobre o gerenciamento da liberação de fármacos, todavia, só a partir do teste de dissolução que constitui a segunda etapa deste projeto poderemos definir qual das formulações propostas será mais eficaz no controle da cinética de liberação.


In this study, core tablets of dry theophylline were compressed coated using the system pectin-HPMC for controlled drug delivery. The methodology applied produced coated tablets with suitable physical characteristics according to Brazil Pharmacopeia 4th edition. The physical properties were evaluated for different ratios (80:20, 60:40, 50:50, 40:60, 20:80, 0:100) of pectin-HPMC, respectively, and the swelling test was carried out in simulated gastric fluid (pH 1.2) and in simulated intestinal fluid (pH 6.8). The method applied gave origin to coated tablets with high expectation in the kinetics control of drug release. From the statistics analyses of the results obtained, it was observed that results were not significant between different ratios.


Assuntos
Pectinas , Comprimidos com Revestimento Entérico , Teofilina , Biotecnologia
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