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1.
Heliyon ; 10(8): e29342, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38628734

RESUMO

Objective: In this study, the effect of in vitro Fertilization-Embryo Transfer (IVF-ET) on the clinical outcome of patients with syphilis infertility during resuscitation cycle. Methods: A retrospective single-center method was adopted. This study included 4430 pairs of infertile patients who underwent syphilis detection. The influence of the syphilis freeze-thaw embryos transplantation outcome was studied in the patients with infertility by comparing the general clinical characteristics of patients (age, years of infertility, body mass index (BMI), basal follicle stimulating hormone (FSH), serum basal estradiol (Estradiol, E2), transplanted intimal thickness, the number of embryos transferred) and the clinical pregnancy (biochemical pregnancy rate, clinical pregnancy rate, implantation rate, live birth rate and abortion rate). Results: Firstly, in the clinical outcome of one frozen-thawed embryos transfer, the live birth rate of the woman's syphilis-infected group was lower than that of the uninfected group (71.3 % vs. 50.0 %), while the abortion rate was higher than that of the uninfected group (7.8 % vs. 26.7 %), and there was a statistical difference (P < 0.05), and there was no statistical difference in other indicators between other groups (P > 0.05). Secondly, in the clinical outcome of two frozen-thawed embryos transfers, the biochemical pregnancy rate (61.3 % vs. 28.6 %) and clinical pregnancy rate (42.9 % vs. 14.3 %) of the group which was infected with syphilis alone were lower than those of the uninfected group (P < 0.05), and other indicators among the other groups showed no statistical difference (P > 0.05). Thirdly, in the clinical outcomes of frozen-thawed embryos transfer three times or more, there was no significant difference in the clinical indicators between the syphilis infertility patients and the non-infected infertility patients (P > 0.05). Conclusion: When the syphilis infertility patients and the non-infected infertile patients underwent IVF-ET treatment for the first time, the live birth rate and abortion rate of the syphilis group were significantly different (P < 0.05). In the outcome of two transplants, the biochemical pregnancy rate and clinical Pregnancy rates were significantly reduced so patients with syphilis infertility who undergo IVF-ET should be informed about the risk of adverse clinical outcomes.

2.
J Clin Hypertens (Greenwich) ; 26(5): 465-473, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38468407

RESUMO

This study illustrated the effectiveness of the knowledge, attitude, practice (KAP) intervention model for community hypertension in the elderly by the community physician-led, describing the study design and baseline data. The aim of the study was to compare the changes in the elderly hypertensive population before and after the KAP intervention model by managing the elderly hypertensive patients for a period of 1 year. Basic information and risk factors affecting blood pressure control based on baseline data of recruited elderly hypertensive patients. The management approach consists of two parts: (1) the unified management of the community physician to whom the patient belongs; and (2) the management of the contracted patient by the community physician. The aim was to demonstrate the anti-hypertensive effectiveness (control rate, blood pressure reduction, and pulse pressure), the distribution of blood pressure types, and the change of the KAP in elderly hypertensive patients before and after the intervention. The KAP intervention model was administered to 2660 elderly hypertensive patients in a 1-year period. The blood pressure control rate improved by 54.03%. Mean values of overall systolic and diastolic blood pressure decreased by 16.00 and 5.31 mmHg, respectively. The proportion of isolated systolic hypertension (ISH) and systolic-diastolic hypertension (SDH) decreased by 29.14% and 24.81%, respectively. The KAP compliance improved significantly. These results suggest that the community physician-led KAP intervention model is effective in the management of hypertension in the elderly.


Assuntos
Anti-Hipertensivos , Pressão Sanguínea , Conhecimentos, Atitudes e Prática em Saúde , Hipertensão , Humanos , Hipertensão/terapia , Hipertensão/tratamento farmacológico , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Hipertensão/diagnóstico , Idoso , Masculino , Feminino , Anti-Hipertensivos/uso terapêutico , Pressão Sanguínea/fisiologia , Idoso de 80 Anos ou mais , Fatores de Risco
3.
Reprod Biol Endocrinol ; 19(1): 167, 2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34740363

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is a common endocrine and metabolic disease in women at childbearing age. Several circular RNAs (circRNAs) have been demonstrated to be involved in PCOS. In this study, we aimed to explore the function and mechanism of circ_0043532 in PCOS. METHODS: Quantitative real-time polymerase chain reaction (qRT-PCR) was performed to determine the expression of circ_0043532, miR-182 and serum/glucocorticoid regulated kinase family member 3 (SGK3). Cell proliferation was assessed by 5-ethynyl-2'-deoxyuridine (EdU) assay and 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay. Flow cytometry analysis was employed to evaluate cell cycle and cell apoptosis. Dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were conducted to verify the association between miR-182 and SGK3. Western blot assay was carried out to determine the protein level of SGK3. RESULTS: Circ_0043532 was markedly elevated in PCOS granulosa cells (GCs) and KGN cells. Silencing of circ_0043532 suppressed cell proliferation and cell cycle process and promoted cell apoptosis in PCOS GCs and KGN cells. For mechanistic analysis, circ_0043532 was identified as a sponge of miR-182 and SGK3 was confirmed to be a target gene of miR-182. Inhibition of miR-182 rescued the impacts of circ_0043532 interference on PCOS GCs and KGN cell progression. Moreover, miR-182 overexpression suppressed cell proliferation and cell cycle process and promoted cell apoptosis in PCOS GCs and KGN cells by targeting SGK3. CONCLUSION: Deficiency of circ_0043532 suppressed cell proliferation and induced cell cycle arrest and cell apoptosis in PCOS by modulation of miR-182/SGK3 axis.


Assuntos
Proliferação de Células/fisiologia , Células da Granulosa/metabolismo , MicroRNAs/biossíntese , Síndrome do Ovário Policístico/metabolismo , Proteínas Serina-Treonina Quinases/biossíntese , RNA Circular/biossíntese , Adulto , Movimento Celular/fisiologia , Feminino , Células da Granulosa/patologia , Humanos , MicroRNAs/genética , Síndrome do Ovário Policístico/genética , Síndrome do Ovário Policístico/patologia , Proteínas Serina-Treonina Quinases/genética , RNA Circular/genética , Adulto Jovem
4.
Mol Med Rep ; 10(1): 560-6, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24820764

RESUMO

Phosphocreatine (PCr) mobilizes high-energy phosphates in cardiac muscles, which is potentially useful as a cardioprotective agent in patients with spinal cord injury (SCI). The cardioprotective effects of PCr on myocardial cell ultrastructure and calcium-sensing receptor (CaSR) expression following high-level spinal cord injury (SCI) were investigated. Healthy adult male Sprague-Dawley (SD) rats (n=54) weighing 250-300 g were subjected to C7 SCI injury by Allen's method with or without treatment by abdominal injection of PCr (200 mg/kg) at 6, 12, 24 or 48 h (SCI + treatment and SCI-only groups, respectively; 6 rats/group/time point). Right apical tissues were sampled 2 h following each time interval. Surgeries without SCI were performed in 6 control rats (sham operation group). Cardiac troponin I (cTnI), serum creatine kinase (CK) and creatine kinase (CK-MB) levels were assessed automatically. Myocardial morphology was examined by transmission electron microscopy (TEM). Quantitative real­time polymerase chain reaction (qRT-PCR) and western blot analysis were used to determine myocardial tissue calcium-sensing receptor (CaSR) mRNA and protein expression, respectively. Normal myocardial ultrastructure was observed in the sham operation group, while SCI-only groups exhibited progressive and extensive damage to myofibrils, sarcomere structure, mitochondrial membranes and vacuole structures, occasionally accompanied by punctured cell membranes, nuclear chromatin condensation and cavitation. SCI + treatment groups, however, exhibited significantly relieved ultrastructural abnormalities and reduced the levels of CaSR, cTnI, CK and CK-MB mRNA and protein expression at all time intervals (P<0.05). In the SCI rat model, PCr exhibited cardioprotection by relieving myocardial ultrastructural abnormalities and preserving the normal metabolic energy balance, including calcium regulation.


Assuntos
Cardiotônicos/farmacologia , Miócitos Cardíacos/efeitos dos fármacos , Fosfocreatina/farmacologia , Receptores de Detecção de Cálcio/metabolismo , Traumatismos da Medula Espinal/patologia , Doença Aguda , Animais , Cardiotônicos/uso terapêutico , Creatina Quinase/sangue , Creatina Quinase Forma MB/sangue , Masculino , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/ultraestrutura , Necrose , Fosfocreatina/uso terapêutico , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Receptores de Detecção de Cálcio/genética , Traumatismos da Medula Espinal/tratamento farmacológico , Traumatismos da Medula Espinal/metabolismo , Fatores de Tempo , Troponina I/sangue
5.
Drug Dev Ind Pharm ; 40(1): 126-35, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23336809

RESUMO

OBJECTIVE: The aim of this study was to evaluate the applicability of POVACOAT™, a hydrophilic PVA copolymer, as a solid dispersion (SD) carrier for hot-melt extrusion (HME). METHODS: Bifendate (DDB), a water-insoluble drug, was chosen as the model drug. DDB was hot-melt extruded by a co-rotating twin screw extruder with POVACOAT™. The SD formability of POVACOAT™ was investigated by varying the composition ratios. Solid state characterization was evaluated by differential scanning calorimetry, powder X-ray diffraction, scanning electron microscopy and Fourier transformation infrared spectroscopy. In order to have a better knowledge of the mechanism of dissolution enhancement, dissolution study, phase solubility study and crystallization study of DDB from supersaturated solutions were performed. In addition, the storage stability of the extrudate containing 10% DDB was investigated. RESULTS: Physical characterizations showed that DDB was amorphous up to 15% drug loading. The phase solubility study revealed an AL-type curve. Moreover, POVACOAT™ was found to have an inhibitory effect on crystallization from supersaturated solutions. Compared with the pure DDB and physical mixture, the dissolution rate and solubility of extrudates were significantly enhanced and the drug loading markedly affected the dissolution of SDs. Furthermore, the stability test indicated that 10% DDB-SD was stable during storage (40 °C/75% RH). CONCLUSION: The results of this study demonstrate that POVACOAT™ is a valuable excipient for the formulation of solid dispersions prepared by HME to improve dissolution of poorly water-soluble drugs.


Assuntos
Compostos de Bifenilo/administração & dosagem , Portadores de Fármacos/química , Polímeros/química , Acrilatos/química , Compostos de Bifenilo/química , Química Farmacêutica/métodos , Cristalização , Composição de Medicamentos/métodos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Interações Hidrofóbicas e Hidrofílicas , Metilmetacrilato/química , Álcool de Polivinil/química , Solubilidade
6.
Drug Dev Ind Pharm ; 39(1): 109-16, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22339205

RESUMO

The main purpose of this paper was to improve the dissolution and bioavailability of Ginsenosides (GS) which contained 20(S)-protopanaxadiol (PPD) and 20(S)-protopanaxatriol (PPT) by two methods, and to compare their performance in vitro and in vivo with GS extracts. GS-solid dispersion (SD) were prepared by hot melt extrusion (HME), and GS coground mixture were prepared by cogrinding. In 500 mL 0.1% sodium dodecyl sulfate (SDS) aqueous solution, dissolution of GS-SD and GS coground mixture were both improved comparing with GS extracts. And dissolution of GS-SD was above 90%, which was better than GS coground mixture whose dissolution was about 70%. In GS-SD, GS coground mixture and GS extracts, the AUC(0 → 48) of PPD were 1439.9 ± 435.71, 1618.2 ± 571.9 and 1089.8 ± 359.9 ng · h/mL, and the AUC(0 → 48) of PPT were 683.1 ± 197.7, 736.0 ± 226.0 and 439.8 ± 193.6 ng · h/mL. The results revealed that bioavailability of GS-SD and GS coground mixture was better than GS extracts, but bioavailability of GS-SD was lower than GS coground mixture, which was not consistent with the results of dissolution. The results perhaps caused by the phospholipid in GS coground mixture which played a role as absorption enhancement. It is apparent that both HME and cogrinding can improve the dissolution and bioavailability of GS.


Assuntos
Composição de Medicamentos/métodos , Ginsenosídeos/farmacocinética , Animais , Disponibilidade Biológica , Cães , Feminino , Ginsenosídeos/química , Temperatura Alta , Masculino , Solubilidade
7.
Drug Dev Ind Pharm ; 39(7): 936-46, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23046250

RESUMO

The objective of the present study was to develop stable pellets-layered Simvastatin (SIM) nanosuspensions with improved dissolution and bioavailability. The nanosuspensions were prepared with 7% HPMC, antioxidant 0.03% butylated hydroxyanisole and 0.2% citric acid (m/v) by low temperature grinding. After that, SDS with SIM was in a ratio of 1:5 (m/m), was evenly dispersed in the nanosuspensions. Then, they were layered on the surface of sugar pellets. The mean particle size of the SIM nanosuspensions was 0.74 µm, and 80.6% of the particles was below 1 µm in size. The pellets could re-disperse into nanoparticle status in the dissolution medium. In 900 mL pH 7.0 phosphate solutions, the dissolution of the layered pellets was better than that of commercial tablets. Also, nearly 100% of the drug dissolved from the pellets within 5 min under sink conditions. During the stability studies, SIM pellets exhibited good physical and chemical stability. The relative bioavailability of SIM and Simvastatin ß-hydroxy acid (SIMA) for nanosuspensions layered pellets compared with commercial tablets was 117% and 173%, respectively. The bioavailability of SIMA was improved significantly (p < 0.05), confirming the improvement of bioavailability. Thus, the present study demonstrates that the pellet-layered SIM nanosuspensions improved both the dissolution and bioavailability of SIM.


Assuntos
Inibidores de Hidroximetilglutaril-CoA Redutases/química , Nanopartículas/química , Sinvastatina/química , Animais , Disponibilidade Biológica , Varredura Diferencial de Calorimetria , Cães , Estabilidade de Medicamentos , Derivados da Hipromelose , Metilcelulose/administração & dosagem , Metilcelulose/análogos & derivados , Microscopia Eletrônica de Varredura , Nanopartículas/administração & dosagem , Tamanho da Partícula , Sinvastatina/administração & dosagem , Sinvastatina/farmacocinética , Solubilidade , Suspensões , Difração de Raios X
8.
Int J Pharm ; 422(1-2): 9-16, 2012 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-22001837

RESUMO

The objective of this study was to develop none gastric resident sustained-release pellets loaded with dipyridamole with a high bioavailability. Two different kinds of core pellets, one containing citric acid as a pH-modifier (CAP) and, the other without pH-modifier (NCAP) were prepared by extrusion-spheronization and then coated with mixtures of enteric soluble and insoluble polymers (referred to as CAP(1) and NCAP(1)) or insoluble polymer alone (referred to as CAP(2) and NCAP(2)). The relative bioavailability of the sustained-release pellets was studied in fasted beagle dogs after oral administration using a commercially available immediate release tablet (IRT) as a reference. The in vitro release, in vivo absorption and in vitro-in vivo correlation were also evaluated. Results revealed that the plasma drug concentrations after administration of CAP(2), NCAP(1) and NCAP(2) were undetectable, indicating that the drug release was almost zero from the preparations throughout the gastro-intestinal tract. The C(max), T(max) and AUC((0→24)) of CAP(1) were 0.78 ± 0.23 (µg/ml), 3.80 ± 0.30 (h), and 6.74 ± 0.47 (µg/mlh), respectively. While the corresponding values were 2.23 ± 0.32 (µg/ml), 3.00 ± 0.44 (h) and 9.42 ± 0.69 (µg/mlh) for IRT. The relative bioavailability of CAP(1) was 71.55% compared with IRT. By combined incorporation of a pH-modifier into the core of pellets to modify the inner micro-environment and employing mixtures of enteric soluble and insoluble polymers as a retarding layer, drugs with high solubility in stomach and limited solubility in small intestine, such as DIP, could be successfully formulated as sustained release preparations with no pH-dependence in drug release and enhanced bioavailability.


Assuntos
Dipiridamol/farmacocinética , Inibidores da Agregação Plaquetária/farmacocinética , Administração Oral , Animais , Disponibilidade Biológica , Química Farmacêutica , Ácido Cítrico/química , Dipiridamol/administração & dosagem , Dipiridamol/sangue , Dipiridamol/química , Cães , Composição de Medicamentos , Concentração de Íons de Hidrogênio , Metacrilatos/química , Microscopia Eletrônica de Varredura , Modelos Biológicos , Inibidores da Agregação Plaquetária/administração & dosagem , Inibidores da Agregação Plaquetária/sangue , Inibidores da Agregação Plaquetária/química , Polímeros/química , Solubilidade , Propriedades de Superfície , Comprimidos com Revestimento Entérico , Tecnologia Farmacêutica/métodos
9.
Drug Dev Ind Pharm ; 38(6): 735-43, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21999610

RESUMO

OBJECTIVE: The aim of this study was to evaluate several polymer carriers with regard to the bioavailability enhancement of bifendate solid dispersions (SD) prepared by hot-melt extrusion (HME) and select the most appropriate polymer carrier. METHODS: Solid dispersions containing bifendate in different polymers, including Plasdone(®) S-630, Eudragit(®) EPO and Kollidon(®) VA 64 were prepared by hot-melt extrusion. Differential scanning calorimetry (DSC), Powder X-ray diffraction (XRD) and dissolution testing were used to characterize the systems. Then, the thermal degradation during the HME process and the storage stability of tablets consisting of bifendate-Kollidon(®) VA 64 SD were investigated. Finally, the oral bioavailability of bifendate dosage forms with bifendate-Plasdone(®) S-630 (1/9), bifendate-Eudragit(®) EPO (1/4) and bifendate-Kollidon(®) VA 64 (1/9) SD in beagle dogs was compared with that of commercially available benfidate pills. RESULTS: DSC and XDR analysis showed the dispersion of the drug in the polymer on a molecular basis or in the amorphous state. The drug release from both bifendate-Plasdone(®) S-630 SD and bifendate-Eudragit(®) EPO SD was up to more than 90% with the pH 1.2 simulated gastric fluid as the dissolution medium, while the relative bioavailability was just 87.8 ± 51.8% and 110 ± 62% compared with commercial pills, respectively. The directly compressed tablets with bifendate-Kollidon(®) VA 64 SD were found to dissolve rapidly over 95% within 30 min and the relative bioavailability was 145.0 ± 35.2%. CONCLUSION: The bioavailability of water-insoluble bifendate was markedly enhanced by dispersing the drug in the polymer carrier Kollidon(®) VA 64 employing HME technology.


Assuntos
Compostos de Bifenilo/química , Portadores de Fármacos/química , Polímeros/química , Animais , Disponibilidade Biológica , Cães , Composição de Medicamentos/métodos , Temperatura Alta , Solubilidade
10.
Int J Pharm ; 410(1-2): 180-7, 2011 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-21414393

RESUMO

The main purpose of this study was to prepare nimodipine-loaded nanoliposomes for injection and evaluate their characteristics after lyophilization. Nimodipine-loaded nanoliposomes were prepared by the emulsion-ultrasonic method with sodium cholesterol sulfate (SCS) as the regulator and then lyophilized by adding different cryoprotectants. SCS was used as a blender of regulator and surfactant and helped to prepare smaller liposomes due to the steric hindrance of the sulfate group. The results showed that nimodipine-loaded nanoliposomes with a 20:1 of egg yolk lecithin PL-100M vs. SCS ratio had a particle size of 86.8±42.007 nm, a zeta potential of -13.94 mV and an entrapment efficiency (EE) of 94.34% and could be stored for 12 days at 25°C. Because of the good bulking effect of mannitol and the preservative effect of trehalose, they were used to obtain suitable lyophilized nanoliposomes. The lyophiles containing 10% mannitol and 20% trehalose had a good appearance and a slightly altered particle size after rehydration. In addition, the lyophilized products were characterized by differential scanning calorimetry, X-ray diffraction and scanning electron microscopy, which confirmed the morphous state of trehalose, mannitol and the mixture. Trehalose could inhibit mannitol crystallization to some extent. The drug release from nanoliposomes before and after lyophilization in pH 7.4 phosphate buffer containing 30% ethanol was also examined and both profiles were found to fit the Viswanathan equation. This means that the drug release was controlled by the pore diffusion resistance.


Assuntos
Bloqueadores dos Canais de Cálcio/administração & dosagem , Excipientes/química , Nanopartículas , Nimodipina/administração & dosagem , Bloqueadores dos Canais de Cálcio/química , Varredura Diferencial de Calorimetria , Ésteres do Colesterol/química , Crioprotetores/química , Armazenamento de Medicamentos , Emulsões , Liofilização , Lipossomos , Manitol/química , Microscopia Eletrônica de Varredura , Nimodipina/química , Tamanho da Partícula , Tensoativos/química , Trealose/química , Difração de Raios X
11.
Int J Pharm ; 411(1-2): 188-96, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21421039

RESUMO

To reduce the severe adverse effects of vinorelbine (VRB) with the aim of improving patient compliance, a parenteral vinorelbine-loaded lipid emulsion (VLE) has been developed. The objective of the present study was to get insight into the preclinical antitumor efficacy, toxicity and safety of VLE, and compare this with that of the commercial product, Navelbine(®) i.v. (VS). Comparable antitumor efficacy of VLE and VS was observed in tumor-bearing nude mouse models inoculated with A549 human lung cancer, hepatoma solidity (Heps) G2 cancer and BCAP-37 human breast cancer cells. The median lethal dose (LD(50)) in mice was 29.3mg/kg (male) and 32.1mg/kg (female) for VLE, while the corresponding value was 30.5mg/kg (male and female) for VS. In the long-term toxicity study, VLE significantly reduced the decreases in RBC, HC, WBC and WBC differential count (DC) levels. Lesions in spleen, thymus, lymph nodes, bone marrow, testis, ovary and injection site induced by VS were much more severe compared with VLE. VLE also exhibited less local venous irritation than VS, as well as no hemolysis or hypersensitivity. Consequently, these observations clearly indicate that the lipid emulsion could be a useful potential parenteral carrier for VRB with equivalent efficacy and lower toxicity.


Assuntos
Antineoplásicos Fitogênicos/toxicidade , Sistemas de Liberação de Medicamentos , Vimblastina/análogos & derivados , Animais , Antineoplásicos Fitogênicos/administração & dosagem , Antineoplásicos Fitogênicos/farmacologia , Linhagem Celular Tumoral , Avaliação Pré-Clínica de Medicamentos , Emulsões , Feminino , Humanos , Hipersensibilidade , Infusões Parenterais , Irritantes/administração & dosagem , Irritantes/farmacologia , Irritantes/toxicidade , Dose Letal Mediana , Lipídeos/administração & dosagem , Lipídeos/farmacologia , Lipídeos/toxicidade , Masculino , Camundongos , Camundongos Nus , Vimblastina/administração & dosagem , Vimblastina/farmacologia , Vimblastina/toxicidade , Vinorelbina
12.
Int J Pharm ; 406(1-2): 84-90, 2011 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-21219996

RESUMO

The purpose of the present study was to prepare matrix extended release pellets of diclofenac potassium using low amount of release-modifying agents and, to compare its performance in vivo with coated pellets and matrix tablets. Coated pellets were prepared by extrusion-spheronization, followed by double layer coating using different polymers separately. Matrix pellets with different release rate in vitro were prepared by extrusion-spheronization with different kinds of retarding materials. Bioavailability study of different coated pellets revealed that the drug concentration in plasma of beagle dogs was too low to be detected and, implied that the drug was nearly not released from the preparations before reaching colon due to the appearance of lag time in the dissolution process. The phenomenon indicated that slow-release pellets of diclofenac potassium perhaps should not be developed as double membrane-controlled type. The AUC((0 → 24)) of the immediate release pellets, the two matrix pellets and the reference were 304.4, 87.7, 204.1 and 179.1 µg h/ml, respectively. The C(max) of the formulations mentioned above were 46.3, 13.0, 33.6 and 32.1 µg/ml, respectively. All the matrix formulations, including the reference, exhibited incomplete absorption due to the short small intestine transit time and termination of the drug release in the colon because of its limited solubility. The matrix pellets were bioequivalent with the commercially available tablet (Voltaren(®)) although the drug release in vitro of the former was much faster, while the bioavailability of the matrix pellets with similar in vitro drug release to the reference (Voltaren(®)) was much lower than the latter. The results perhaps was caused by lacking of physical robustness in the waxy tablet formulation, resulted in low wet strength and easily destroyed by the mechanical destructive forces and finally introduced faster drug release rate in vivo. It is apparent that preparations with similar performance in vitro may differ a lot in vivo because of the differences in drug release rate in vivo owing to various wet strengths of excipients contained, especially for sustained release products.


Assuntos
Diclofenaco , Polímeros/química , Animais , Disponibilidade Biológica , Química Farmacêutica , Diclofenaco/administração & dosagem , Diclofenaco/sangue , Diclofenaco/química , Cães , Solubilidade , Comprimidos com Revestimento Entérico
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