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1.
Climacteric ; 27(3): 236-244, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38318859

RESUMO

The issue of vaginal dryness in genitourinary syndrome of menopause (GSM) and its pervasive impact on women's quality of life is often overlooked. Extensive surveys conducted worldwide reveal limited understanding of vaginal dryness among public and health-care providers. Physician knowledge on menopause medicine varies globally, highlighting the need for standardized training. Effective communication between physicians and patients plays a crucial role in diagnosing and treating GSM symptoms. There are multiple treatment options to improve vaginal lubrication, including hormonal and non-hormonal therapies, along with lifestyle modifications. Tailoring treatments to individual patient preferences is crucial for compliance. Overall, GSM is multifaceted, from the prevalence of vaginal dryness to the nuances of treatment preferences. The urgency of widespread education and awareness of this matter must be underscored to meet the aim of enhancing the well-being and quality of life for women.


Assuntos
Menopausa , Qualidade de Vida , Doenças Vaginais , Humanos , Feminino , Menopausa/fisiologia , Doenças Vaginais/terapia , Vagina , Terapia de Reposição de Estrogênios
2.
Med J Malaysia ; 75(3): 286-291, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32467546

RESUMO

AIM: This study is conducted to compare the pharmacokinetic profiles of two fixed dose combination of metformin/glibenclamide tablets (500mg/5 mg per tablet). MATERIALS AND METHODS: This is a single-center, single-dose, open-label, randomized, 2-treatment, 2-sequence and 2- period crossover study with a washout period of 7 days. All 28 adult male subjects were required to fast for at least 10 hours prior to drug administration and they were given access to water ad libitum during this period. Thirty minutes prior to dosing, all subjects were served with a standardized high-fat and high-calorie breakfast with a total calorie of 1000 kcal which was in accordance to the EMA Guideline on the Investigation of Bioequivalence. Subsequently, subjects were administered either the test or reference preparation with 240mL of plain water in the first trial period. During the second trial period, they received the alternate preparation. Plasma levels of glibenclamide and metformin were analysed separately using two different high performance liquid chromatography methods. RESULTS: The 90% confidence interval (CI) for the ratio of the AUC0-t, AUC0-∞, and Cmax of the test preparation over those of the reference preparation were 0.9693-1.0739, 0.9598- 1.0561 and 0.9220 - 1.0642 respectively. Throughout the study period, no serious drug reaction was observed. However, a total of 26 adverse events (AE)/side effects were reported, including 24 that were definitely related to the study drugs, namely giddiness (n=17), while diarrheoa (n=3), headache (n=2) and excessive hunger (n=2) were less commonly reported by the subjects. CONCLUSION: It can be concluded that the test preparation is bioequivalent to the reference preparation.


Assuntos
Glibureto/administração & dosagem , Glibureto/farmacocinética , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacocinética , Metformina/administração & dosagem , Metformina/farmacocinética , Equivalência Terapêutica , Adolescente , Adulto , Estudos Cross-Over , Quimioterapia Combinada , Humanos , Masculino , Adulto Jovem
3.
Eur J Clin Nutr ; 71(1): 107-114, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27759074

RESUMO

BACKGROUND/OBJECTIVES: Evidence shows that tocotrienols potentially reverse various chronic disease progressions caused by the metabolic syndrome. We aimed to investigate the acute effects of a single-dose supplementation of gamma and delta tocotrienols (γδ-T3, 1:4 ratio) compared with those in placebo on the insulinemic, anti-inflammatory and anti-thrombogenic responses in metabolic syndrome subjects. SUBJECTS/METHODS: Thirty metabolic syndrome subjects (15 men and 15 women) were recruited to a randomized, double-blinded and crossover study. The subjects were administered a single dose of 200 mg or 400 mg γδ-T3 emulsions or placebo incorporated into a glass of strawberry-flavored milkshake, consumed together with a high-fat muffin. Blood samples were collected at 0, 5, 15, 30, 60, 90, 120, 180, 240, 300 and 360 min after meal intake. RESULTS: Plasma vitamin E levels reflected the absorption of γδ-T3 after treatments. Postprandial changes in serum C-peptide, serum insulin, plasma glucose, triacylglycerol, non-esterified fatty acid and adiponectin did not differ between treatments, with women displaying delayed increase in the aforementioned markers. No significant difference between treatments was observed for plasma cytokines (interleukin-1 beta, interleukin-6 and tumor necrosis factor alpha) and thrombogenic markers (plasminogen activator inhibitor type 1 and D-dimer). CONCLUSIONS: Supplementation of a single dose of γδ-T3 did not change the insulinemic, anti-inflammatory and anti-thrombogenic responses in metabolic syndrome subjects.


Assuntos
Suplementos Nutricionais , Síndrome Metabólica/terapia , Período Pós-Prandial/efeitos dos fármacos , Tocotrienóis/farmacologia , Vitaminas/farmacologia , Adiponectina/sangue , Adulto , Anti-Inflamatórios/farmacologia , Glicemia/efeitos dos fármacos , Peptídeo C/sangue , Estudos Cross-Over , Dieta Hiperlipídica/efeitos adversos , Dieta Hiperlipídica/métodos , Método Duplo-Cego , Ácidos Graxos não Esterificados/sangue , Feminino , Fibrinolíticos/farmacologia , Humanos , Insulina/sangue , Masculino , Síndrome Metabólica/fisiopatologia , Pessoa de Meia-Idade , Triglicerídeos/sangue , Vitamina E/sangue , Adulto Jovem
4.
J Interpers Violence ; 28(11): 2181-202, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23400883

RESUMO

Advocacy intervention has been shown to be efficacious at reducing depressive symptoms in women who suffer from intimate partner violence (IPV). However, the intervention effect among abused immigrant women has not been well studied. This study compares the demographic and psychosocial characteristics between abused immigrant and nonimmigrant women, and evaluates the impact of immigration status on the efficacy of an advocacy intervention in reducing depressive symptoms and improving perceived social support. Two hundred abused Chinese women recruited from a local community center in Hong Kong were randomized to receive either the advocacy intervention or usual care. The advocacy intervention was found to be effective at reducing depressive symptoms and improving social support for abused Chinese nonimmigrant women, but the same effects were not seen for abused immigrant women. The findings provide essential insights into the need for developing targeted and efficacious advocacy interventions for abused immigrant women. Effective services to address abused immigrant women's needs were also suggested.


Assuntos
Povo Asiático , Mulheres Maltratadas/psicologia , Serviços Comunitários de Saúde Mental , Depressão/prevenção & controle , Emigrantes e Imigrantes , Parceiros Sexuais , Adulto , Povo Asiático/psicologia , China , Emigrantes e Imigrantes/psicologia , Feminino , Humanos , Pessoa de Meia-Idade , Estados Unidos/epidemiologia
5.
J Clin Pharm Ther ; 35(6): 691-6, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21054461

RESUMO

WHAT IS KNOWN AND BACKGROUND: Eurycoma longifolia (E. longifolia), a herb commonly consumed for its aphrodisiac properties, is widely used by Asian males. This may include hypertensive patients receiving propranolol which may cause sexual dysfunction as one of its side-effects. There is no published study of the potential pharmacokinetic interaction between propranolol and the herb. OBJECTIVE: To study propranolol's pharmacokinetics when E. longifolia is consumed, comparing volunteers given either propranolol or a placebo. METHODS: This is a placebo-controlled randomized single-blinded crossover study of the effect of a water-based extract of E. longifolia on the pharmacokinetics of a single dose of proporanolol (Inderal(®)) in 14 healthy non-smoker young males. Eighty milligram of propranonol was orally administered with (i) placebo (Lactose) or (ii) 200 mg of water-based extract of E. longifolia (0·0272 ± 0·0026%eurycomanone) following an overnight fasting. Blood samples were collected at 0, 0·5, 1, 1·5, 2, 3, 4, 6, 8 and 10 h for propranolol's plasma concentration determinations using a validated high-performance liquid chromatography (HPLC) method. RESULTS AND DISCUSSION: When propranolol was administered with E. longifolia, its bioavailability (AUC0-∞) decreased by 29% while C(max) was reduced by 42% and T(max) was significantly prolonged by almost 86%. The terminal elimination half-life, however, was not significantly affected. CONCLUSION: The bioavailability of propranolol is significantly decreased when consumed together with E. longifolia. The interaction is due to a reduction in absorption, rather than an increase in propranolol's metabolism. Although the pharmacodynamics of propranolol was not affected in healthy volunteers, caution is still advisable with co-administration of the drug and the herb.


Assuntos
Afrodisíacos/farmacologia , Eurycoma , Interações Ervas-Drogas , Extratos Vegetais/farmacologia , Propranolol/farmacocinética , Quassinas/farmacologia , Adulto , Área Sob a Curva , Disponibilidade Biológica , Estudos Cross-Over , Meia-Vida , Humanos , Masculino , Fitoterapia , Raízes de Plantas/química , Propranolol/sangue , Propranolol/farmacologia , Disfunções Sexuais Fisiológicas/tratamento farmacológico , Método Simples-Cego , Água , Adulto Jovem
6.
J Dairy Sci ; 93(11): 5048-58, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20965319

RESUMO

This randomized, double-blind, placebo-controlled, and parallel-designed study was conducted to investigate the effect of a synbiotic product containing Lactobacillus gasseri [corrected] CHO-220 and inulin on lipid profiles of hypercholesterolemic men and women. Thirty-two hypercholesterolemic men and women with initial mean plasma cholesterol levels of 5.7±0.32 mmol/L were recruited for the 12-wk study. The subjects were randomly allocated to 2 groups; namely the treatment group (synbiotic product) and the control group (placebo), and each received 4 capsules of synbiotic or placebo daily. Our results showed that the mean body weight, energy, and nutrient intake of the subjects did not differ between the 2 groups over the study period. The supplementation of synbiotic reduced plasma total cholesterol and low-density lipoprotein (LDL)-cholesterol by 7.84 and 9.27%, respectively, compared with the control over 12 wk. Lipoproteins were subsequently subfractionated and characterized. The synbiotic supplementation resulted in a lower concentration of triglycerides in the very low, intermediate, low, and high-density lipoprotein particles compared with the control over 12 wk. The concentration of triglycerides in lipoproteins is positively correlated with an increased risk of atherosclerosis. Our results showed that the synbiotic might exhibit an atheropreventive characteristic. Cholesteryl ester (CE) in the high-density lipoprotein particles of the synbiotic group was also higher compared with the control, indicating greater transport of cholesterol in the form of CE to the liver for hydrolysis. This may have led to the reduced plasma total cholesterol level of the synbiotic group. The supplementation of synbiotic also reduced the concentration of CE in the LDL particles compared with the control, leading to the formation of smaller and denser particles that are more easily removed from blood. This supported the reduced LDL-cholesterol level of the synbiotic group compared with the control. Our present study showed that the synbiotic product improved plasma total- and LDL-cholesterol levels by modifying the interconnected pathways of lipid transporters. In addition, although Lactobacillus gasseri [corrected] CHO-220 could deconjugate bile, our results showed a statistically insignificant difference in the levels of conjugated, deconjugated, primary, and secondary bile acids between the synbiotic and control groups over 12 wk, indicating safety from bile-related toxicity.


Assuntos
Hipercolesterolemia/tratamento farmacológico , Inulina/uso terapêutico , Lactobacillus/classificação , Simbióticos , Transporte Biológico , Colesterol/sangue , Ésteres do Colesterol/sangue , LDL-Colesterol/sangue , Método Duplo-Cego , Feminino , Humanos , Hipercolesterolemia/sangue , Metabolismo dos Lipídeos , Masculino , Resultado do Tratamento
7.
J Dairy Sci ; 93(10): 4535-44, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20854987

RESUMO

This randomized, double-blind, placebo-controlled, and parallel-design study was conducted to investigate the effect of a synbiotic product containing Lactobacillus gasseri [corrected] CHO-220 and inulin on the irregularity in shape of red blood cells (RBC) in hypercholesterolemic subjects. The subjects (n=32) were randomly allocated to 2 groups, a treatment group (synbiotic product) and a control group (placebo), and received 4 capsules of either synbiotic or placebo daily for 12 wk. Morphological representation via scanning electron microscopy showed that the occurrence of spur RBC was improved upon supplementation of the synbiotic. In addition, the supplementation of synbiotic reduced the cholesterol:phospholipids ratio of the RBC membrane by 47.02% over 12 wk, whereas the control showed insignificant changes. Our present study also showed that supplementation of the synbiotic reduced the concentration of saturated fatty acids (SFA), increased unsaturated fatty acids (UFA), and increased the ratio of UFA:SFA over 12 wk, whereas the control showed inconspicuous changes. The alteration of RBC membrane was assessed using fluorescence anisotropy (FAn) and fluorescence probes with different affinities for varying sections of the membrane phospholipid bilayer. A noticeable decrease in FAn of three fluorescent probes was observed in the synbiotic group compared with the control over 12 wk, indicative of increased membrane fluidity and reduced cholesterol enrichment in the RBC membrane.


Assuntos
Eritrócitos/citologia , Hipercolesterolemia/tratamento farmacológico , Inulina/uso terapêutico , Lactobacillus/classificação , Simbióticos , Adulto , Colesterol/sangue , Método Duplo-Cego , Eritrócitos/metabolismo , Ácidos Graxos/sangue , Feminino , Humanos , Masculino , Fluidez de Membrana , Fosfolipídeos/sangue , Resultado do Tratamento
8.
Pharm Dev Technol ; 11(1): 71-7, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16544910

RESUMO

A new approach to developing a drug-polymer mixed coat for highly water-soluble diltiazem pellets was investigated at different coating levels. Drug layering and the coating procedures were performed using a bottom spray fluidized bed coater. Drug pellets were coated with Eudragit NE40 (NE40) alone and in combination with diltiazem and hydrophilic cellulose derivatives. Dissolution studies revealed that incorporation of hydrophilic substances such as methylcellulose (MC), hydroxypropyl methylcellulose (HPMC), and the drug itself considerably increased the release rates. The release from mixed polymer coatings was fast compared to pellets coated with NE40 only. The major portion of the drug was released in about 2 hours in case of MC and NE40 mixed coat compared to hours from coated pellets containing HPMC or diltiazem. Incorporation of 15% to 25% drug with respect to the polymer coat helped to achieve a drug-release profile at a desirable rate over a 12 hour period. Moreover, the test formulation comprising 25% diltiazem with respect to 7% NE40 had a dissolution profile that matched the commercial product, Herbesser SR capsules. The release of diltiazem from the coated pellets was slightly affected by the pH of dissolution media.


Assuntos
Preparações de Ação Retardada/química , Preparações Farmacêuticas/administração & dosagem , Preparações Farmacêuticas/química , Algoritmos , Interpretação Estatística de Dados , Diltiazem/administração & dosagem , Diltiazem/química , Composição de Medicamentos , Armazenamento de Medicamentos , Excipientes , Concentração de Íons de Hidrogênio , Derivados da Hipromelose , Metilcelulose/análogos & derivados , Microscopia Eletrônica de Varredura , Polímeros , Solubilidade
9.
J Contin Educ Nurs ; 36(5): 205-12, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16218008

RESUMO

As medical technologies change, practicing nurses need to update their knowledge and skills to ensure quality health care for patients and to minimize possible health hazards in the workplace. This article describes a study that explored Hong Kong hospital nurses' perceptions of and participation in continuing nursing education. It found that Hong Kong nurses participate actively in continuing education out of a sense of professional responsibility and personal interest. However, consistent with findings from other studies, the major factors hindering nurses' participation are finances, family commitments, and time.


Assuntos
Educação Continuada em Enfermagem , Avaliação das Necessidades , Adulto , Análise de Variância , Tomada de Decisões , Feminino , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa em Educação em Enfermagem , Especialidades de Enfermagem
10.
Pharm Dev Technol ; 10(3): 371-9, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16176017

RESUMO

The gastrointestinal (GI) transit and absorption of a multiparticulate controlled-release diltiazem formulation were investigated with reference to an innovator preparation. Transit of controlled-release pellets in GI tract was monitored using two marker drugs, namely paracetamol and sulfasalazine. Both formulations had little intersubject variation in gastric emptying and small intestine transit time. In both formulations, about 51% to 64% of the drug was absorbed while pellets were in the small intestine and the remaining amount while in the colon. The results found in this study were comparable to the other workers who used gamma scintigraphy or indirect method. Therefore, the method used in this study is a reliable alternative for studying GI transit of pellets.


Assuntos
Diltiazem/administração & dosagem , Diltiazem/farmacocinética , Esvaziamento Gástrico , Trânsito Gastrointestinal , Absorção Intestinal , Acetaminofen/administração & dosagem , Adulto , Ceco/metabolismo , Preparações de Ação Retardada , Humanos , Concentração de Íons de Hidrogênio , Masculino , Solubilidade , Sulfassalazina/administração & dosagem
11.
Drug Dev Ind Pharm ; 31(4-5): 339-47, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-16093199

RESUMO

This study was aimed at developing a controlled-release coating system around core pellets with aqueous dispersion, along with some water channeling agents. Core pellets of diltiazem were prepared using the extrusion-spheronization technique and subsequently coated with aqueous dispersion of Eudragit NE40 alone, or drug-polymer mixtures using bottom-spray fluidized bed coater. The lag time in drug release profiles increased as the coating levels of Eudragit NE40 were increased, whereas no lag time was observed in core pellets coated with drug-polymer mixtures. Mixed coating at the 7% level exhibited comparatively better release profiles and provided desirable release rates during the 12-hour testing interval. Diltiazem HCl release from mixed coating was fairly independent of pH and drug loading. Curing of coated pellets was found to be an essential step for stable drug release profiles. The selection of core size range had remarkable effect on drug release rate and was considerably reduced by using greater core size.


Assuntos
Preparações de Ação Retardada/farmacocinética , Implantes de Medicamento/farmacocinética , Ácidos Polimetacrílicos/química , Bloqueadores dos Canais de Cálcio/química , Bloqueadores dos Canais de Cálcio/farmacocinética , Celulose/química , Celulose/farmacocinética , Preparações de Ação Retardada/química , Diltiazem/química , Diltiazem/farmacocinética , Implantes de Medicamento/química , Concentração de Íons de Hidrogênio , Lactose/química , Lactose/farmacocinética , Microscopia Eletrônica de Varredura/métodos , Permeabilidade , Solubilidade , Tecnologia Farmacêutica/métodos , Temperatura , Fatores de Tempo
12.
Int J Pharm ; 299(1-2): 55-64, 2005 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-15955645

RESUMO

A polyglycolised glyceride carrier, Gelucire 50/13, was incorporated with paracetamol as a model drug, filled into hard gelatin capsules and stored at three different temperatures for various lengths of time. The resultant solidified matrix within the capsule was subjected to thermal analysis using differential scanning calorimetry (DSC) to ascertain its supramolecular structure. Polymorphic transformations towards more stable gelucire forms were observed upon aging the matrices, with samples stored at a temperature near the melting range of the lower temperature gelucire melting fraction showing the most profound changes. The increase in the rate of drug release from aged samples could be correlated to the alterations to the supramolecular structure of the gelucire. Accelerated drug release from aged samples could also be seen from in vivo studies using healthy human volunteers, although the extent of absorption was not affected. Therefore, even though the sustainability of release may be compromised by aging the gelucire matrices, the bioavailability of the incorporated drug is unlikely to be affected.


Assuntos
Acetaminofen/farmacocinética , Gorduras/farmacocinética , Óleos/farmacocinética , Temperatura , Acetaminofen/sangue , Acetaminofen/química , Adulto , Área Sob a Curva , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Cápsulas , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Excipientes/química , Gorduras/química , Humanos , Masculino , Óleos/química , Solubilidade , Fatores de Tempo , Temperatura de Transição
13.
Nurse Educ Today ; 25(4): 299-308, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15896415

RESUMO

There is a wealth of literature demonstrating that clinical nursing education is an important part of the baccalaureate programme in preparing students for entry into the nursing profession. While much attention has been given to the factors that can affect learning outcomes in the clinical environment, student and teacher perceptions of the relationship between assessment and learning has remained an under-researched area. The purpose of this study was to explore the perceptions about what students learned and how they learned during their clinical practicum, and to examine the role played by assessment in influencing student learning. Data were collected through a series of focus group interviews with groups of nursing students, graduates, and teachers. It was revealed that students' learning during the clinical practicum was, to a large extent, affected by their perceptions of the assessment tasks. As a result, they adopted a surface approach to learning and focused on preparing for the assessment tasks to the detriment of their learning. Assessment, in this study, exerted what has been described as a negative "backwash" effect on learning. Since assessment may also foster student learning in a positive way, suggestions are offered as to what can be done to bring about a positive "backwash" effect.


Assuntos
Atitude do Pessoal de Saúde , Competência Clínica/normas , Bacharelado em Enfermagem/normas , Avaliação Educacional/normas , Docentes de Enfermagem , Aprendizagem , Estudantes de Enfermagem/psicologia , Currículo/normas , Grupos Focais , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Mentores/psicologia , Narração , Avaliação das Necessidades , Negativismo , Pesquisa em Educação em Enfermagem , Pesquisa Metodológica em Enfermagem , Teoria de Enfermagem , Psicologia Educacional , Pesquisa Qualitativa , Socialização , Estresse Psicológico/psicologia , Inquéritos e Questionários , Transferência de Experiência
14.
Med J Malaysia ; 59(3): 352-6, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15727381

RESUMO

The bioavailability of a generic diclofenac sodium sustained release tablet preparation (Zolterol, SR) was compared with the innovator product, Voltaren, SR. Twelve healthy adult male volunteers participated in the study, which was conducted according to a randomized, two-way crossover design with a wash out period of one week. The bioavailability of diclofenac was compared using the parameters area under the plasma concentration-time curve (AUC(0-infinity)), peak plasma concentration (Cmax) and time to reach peak plasma concentration (Tmax). No statistically significant difference was observed for both logarithmically transformed AUC(0-infinity), Cmax values and Tmax value of the two preparations.


Assuntos
Anti-Inflamatórios não Esteroides/farmacocinética , Diclofenaco/farmacocinética , Adulto , Anti-Inflamatórios não Esteroides/sangue , Área Sob a Curva , Disponibilidade Biológica , Cromatografia Líquida de Alta Pressão , Estudos Cross-Over , Preparações de Ação Retardada , Diclofenaco/sangue , Humanos , Masculino , Comprimidos
15.
Drug Dev Ind Pharm ; 29(9): 1035-44, 2003 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-14606667

RESUMO

The present study was conducted to investigate the inclusion complexation of artemisinin (ART) with natural cyclodextrins (CyD), namely alpha-, beta-, and gamma-CyDs with the aim of improving its solubility and dissolution rate. Complex formation in aqueous solution and solid state was studied by solubility analysis, dissolution, and thermal analysis. Solubility diagrams indicated that the complexation of ART and the three CyDs occurred at a molar ratio of 1:1, and showed a remarkable increase in ART solubility. Moreover, the thermodynamic parameters calculated by using the van't Hoff equation revealed that the complexation process was associated with negative enthalpy of formation and occurred spontaneously. The complexation capability of CyDs with ART increased in the order of alpha- < gamma- < beta-CyDs and could be ascribed to the structural compatibility between the molecular size of ART and the diameter of the CyD cavities. Dissolution profiles of the three complexes demonstrated an increased rate and extent of dissolution compared with those of their respective physical mixtures and a commercial preparation. In solid-state analysis, using differential scanning calorimetry, the gamma-CyD was capable of complexing the highest percentage of ART, followed by beta- and alpha-CyDs. The respective estimated percentage of ART complexed by the CyDs were 85%, 40%, and 12%.


Assuntos
Artemisininas/química , Ciclodextrinas/química , Sesquiterpenos/química , alfa-Ciclodextrinas , beta-Ciclodextrinas , gama-Ciclodextrinas , Artemisininas/metabolismo , Ciclodextrinas/metabolismo , Relação Dose-Resposta a Droga , Sesquiterpenos/metabolismo , Solubilidade
16.
J Control Release ; 91(3): 477-88, 2003 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-12932724

RESUMO

In this investigation we describe the preparation, physical characterisation and in vivo behaviour of solid dispersions of a liquid nutraceutical, alpha-tocopherol, in Gelucire 44/14 with a view to establishing whether dispersion in this matrix may provide a means of formulating a liquid drug in a solid dosage form while also improving the oral bioavailability. Using Vitamin E Preparation USP as the source of alpha-tocopherol, dispersions were prepared using a melt-fusion method with active loadings up to 50% (w/w) and characterised using differential scanning calorimetry and optical microscopy. Capsules containing 300 IU alpha-tocopherol were manufactured and the absorption profiles compared to a commercial soft gelatin capsule preparation in healthy human volunteers. Confocal laser scanning microscopy (CLSM) studies were performed in order to elucidate the mechanism by which drug release may be occurring. Differential scanning calorimetry studies indicated that the presence of the active had a negligible effect on the melting profile of the carrier, indicating limited miscibility between the two components, a conclusion supported by the microscopy studies. Similarly, the dispersions were shown to exhibit a glass transition corresponding to the incorporated drug, indicating molecular cooperativity and hence phase separation from the lipid base. Despite the phase separation, it was noted that capsules stored for 18 months under ambient conditions showed no evidence of leakage. Bioavailability studies in six healthy male volunteers indicated that the Gelucire 44/14 formulation showed an approximately two-fold increase in total alpha-tocopherol absorption compared to the commercial preparation. Confocal laser scanning microscopy studies indicated that, on contact with water, the dispersions formed two interfacial layers, from which the Gelucire 44/14 disperses in the liquid medium as small particles. Furthermore, evidence was obtained for the dispersed material becoming incorporated into the hydrated lipid. In conclusion, the dispersion of the liquid drug in Gelucire 44/14 appears to allow the dual advantages of the preparation of a solid formulation and improved bioavailability of this material.


Assuntos
Polietilenoglicóis/química , Polietilenoglicóis/farmacocinética , alfa-Tocoferol/química , alfa-Tocoferol/farmacocinética , Adulto , Área Sob a Curva , Disponibilidade Biológica , Humanos , Masculino , Solubilidade/efeitos dos fármacos , Relação Estrutura-Atividade
17.
J Pharm Pharmacol ; 55(2): 193-8, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12631411

RESUMO

We have evaluated the therapeutic equivalence of a beta-cyclodextrin-artemisinin complex at an artemisinin dose of 150 mg, with a commercial reference preparation, Artemisinin 250 at a recommended dose of 250 mg. One hundred uncomplicated falciparum malarial patients were randomly assigned to orally receive either beta-cyclodextrin-artemisinin complex (containing 150 mg artemisinin) twice daily for five days or the active comparator (containing 250 mg artemisinin) twice daily for five days. The patients were hospitalized for seven days and were required to attend follow up assessments on days 14, 21, 28 and 35. All patients in both treatment groups were cured of the infection and achieved therapeutic success. At day seven of treatment, all patient blood was clear of the parasites and the sublingual temperature of all patients was less than 37.5 degrees C. Moreover, the parasite clearance time in both treatment groups was similar, being approximately three days after initiation of treatment. Comparable plasma artemisinin concentrations were observed between patients in both treatment groups at 1.5 and 3.0 h, although slightly higher levels were obtained with patients in the beta-cyclodextrin-artemisinin complex-treated group. The beta-cyclodextrin-artemisinin complex at a dose of 150 mg artemisinin was therapeutically equivalent to 250 mg Artemisinin 250. Additionally, patients receiving beta-cyclodextrin-artemisinin complex showed less variability in their plasma artemisinin concentrations at 1.5 h post-dosing, which suggested a more consistent rate of drug absorption.


Assuntos
Artemisininas/uso terapêutico , Malária Falciparum/tratamento farmacológico , Sesquiterpenos/uso terapêutico , beta-Ciclodextrinas , Adolescente , Adulto , Animais , Artemisininas/sangue , Artemisininas/farmacocinética , Ciclodextrinas/farmacocinética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Plasmodium falciparum/efeitos dos fármacos , Sesquiterpenos/sangue , Sesquiterpenos/farmacocinética , Equivalência Terapêutica , Resultado do Tratamento
18.
Int J Pharm ; 227(1-2): 177-85, 2001 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-11564552

RESUMO

The bioavailability of beta- and gamma-cyclodextrin artemisinin complexes was evaluated in comparison with a normal commercially available preparation, Artemisinin 250. Twelve healthy male volunteers participated in the study conducted according to a three-way crossover design. The bioavailability was compared using the parameters, total area under the plasma level-time curve (AUC(0-infinity)), peak plasma concentration (C(max)), and time to reach peak plasma concentration (T(max)). A statistically significant difference was observed between the values of the complexes and Artemisinin 250 for the three parameters. However, no statistically significant difference was observed between the values of the beta- and gamma-cyclodextrin complexes. Moreover, the 90% confidence interval for the ratio of the AUC(0-infinity) values of the beta-cyclodextrin complex over those of Artemisinin 250 was estimated to be between 1.51-2.04, while that of C(max) was between 1.73-2.93. For the gamma-cyclodextrin complex, the respective intervals were 1.30-1.76 and 1.43-2.43. These findings indicated that the beta- and gamma-cyclodextrin complexes had a much higher rate and extent of bioavailability compared to Artemisinin 250. In addition, the absorption of artemisinin was observed to be poor and negligible when the preparations started to arrive in the colon. This could be attributed to poor dissolution of artemisinin in the semi-solid faecal matter in the lower part of the gastrointestinal tract.


Assuntos
Antimaláricos/farmacocinética , Artemisininas , Ciclodextrinas/farmacologia , Sesquiterpenos/farmacocinética , Adulto , Área Sob a Curva , Disponibilidade Biológica , Estudos Cross-Over , Interações Medicamentosas , Trânsito Gastrointestinal , Meia-Vida , Humanos , Masculino , Taxa de Depuração Metabólica
19.
J Pharm Biomed Anal ; 24(4): 715-9, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11272330

RESUMO

A simple high-performance liquid chromatographic method was developed for the determination of omeprazole in human plasma. Omeprazole and the internal standard, chloramphenicol, were extracted from alkalinized plasma samples using dichloromethane. The mobile phase was 0.05 M Na2HPO4-ACN (65:35, v/v) adjusted to pH 6.5. Analysis was run at a flow rate of 1.0 ml/min at a detection wavelength of 302 nm. The method was specific and sensitive with a detection limit of 2.5 ng/ml at a signal-to-noise ratio of 4:1. The limit of quantification was set at 5 ng/ml. The calibration curve was linear over a concentration range of 5-1280 ng/ml. Mean recovery value of the extraction procedure was about 96%, while the within and between day coefficient of variation and percent error values of the assay method were all less than 14%.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Omeprazol/sangue , Cloranfenicol/sangue , Humanos , Sensibilidade e Especificidade
20.
Int J Clin Pharmacol Ther ; 39(1): 37-40, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11204936

RESUMO

OBJECTIVE: The aim of the present communication is to provide information regarding the intrasubject coefficent of variation obtained from 30 bioequivalence studies covering 16 drugs which can be used for estimation of sample size. Additionally, an attempt was also made to estimate the test power of each of the studies conducted. METHODS: The intrasubject coefficient of variation was estimated from the residual mean square error obtained from analysis of variance of the parameters AUC0-infinity, Cmax and Cmax/AUC0-infinity after logarithmic transformation. The test power in the analyses of the above parameters was subsequently estimated using nomograms provided by Diletti et al. [1991]. RESULTS AND CONCLUSION: Thirty products covering 16 drugs were studied in which 22 were immediate-release (including one dispersible tablet) and 8 were sustained-release formulations. The intrasubject coefficient of variation for the parameter AUC0-infinity was smaller than Cmax, and hence considerably more studies were able to attain a power of greater than 80% using 12 volunteers for the AUC0-infinity, compared to the Cmax. However, the variability in the Cmax could be reduced by using the parameter Cmax/ AUC0-infinity, and thus, provide a more realistic estimation of sample size, since the latter reflects only the rate of absorption and not both the rate and extent as in the case of Cmax [Endrenyi et al. 1991].


Assuntos
Tratamento Farmacológico/estatística & dados numéricos , Farmacocinética , Absorção , Área Sob a Curva , Humanos , Reprodutibilidade dos Testes , Projetos de Pesquisa , Tamanho da Amostra , Equivalência Terapêutica
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