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1.
Eur J Med Res ; 29(1): 110, 2024 Feb 09.
Artigo em Inglês | MEDLINE | ID: mdl-38336775

RESUMO

Aim of this comparative cross-sectional study was to evaluate the effect of anterior teeth retraction and related hard and soft tissue change under physiologic anchorage control in patients with chief complain of protrusive teeth. 68 Class I or II orthodontic patients undergoing four-premolar extraction and requiring maximum or medium anchorage were included. Patients were treated with physiologic anchorage control technique (PASS group, n = 34, 18.6 ± 7.7 years, 10 male and 24 female) and self-ligation technique (Damon group, n = 34, 17.5 ± 5.4 years, 13 male and 21 female), respectively. TADs were used for anchorage reinforcement in Damon group. Pre- and post-treatment cephalograms were collected. Twenty-six skeletal, dental and soft tissue items were measured and analyzed using a blinded method. T test and paired rank-sum test were used for statistical analysis. The baseline characteristics were similar between groups (P > 0.05). After treatment, inter-group comparison showed statistically significant differences in the decrease of skeletal measurements ∠ANB (- 0.73 ± 1.05° in PASS group and - 0.25 ± 0.84° in the Damon group), Wits value (- 2.56 ± 2.29 mm in PASS group and - 0.47 ± 2.15 mm in Damon group) and soft tissue measurement UL-E (- 2.75 ± 1.36 mm in PASS group and - 2.03 ± 1.30 mm in Damon group) and the increase of FCA and Z angle, which was 2.03 ± 2.12°and 9.52 ± 4.78°in PASS group and 0.97 ± 2.12°and 6.96 ± 4.43°in Damon group, respectively (P < 0.05). Our results indicated that significant anterior teeth retraction and profile improvement could be achieved with PASS technique without additional anchorage devices. Appropriate application of physiologic anchorage control could reduce the dependence of TADs for anterior teeth retraction.


Assuntos
Procedimentos de Ancoragem Ortodôntica , Técnicas de Movimentação Dentária , Humanos , Masculino , Feminino , Técnicas de Movimentação Dentária/métodos , Estudos Transversais , Maxila , Cefalometria
2.
Front Pharmacol ; 14: 1176422, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37292147

RESUMO

Oral squamous cell carcinoma (OSCC) is a common human malignancy with an estimated incidence of around 377,713 new cases worldwide in 2020. Despite the advance in clinical management, some of OSCC patients still miss the opportunity of completable resection of tumor, and have to accept medical therapies, e.g., chemotherapy, radiotherapy, or immunotherapy when the disease develops into the advanced stage. However, these therapies have been reported to be far from ideal due to the low efficiency of conventional delivery approaches. To obtain a better therapeutic effect, considerable attempts have been made toward to develop an effective drug delivery system (DDS). Nanoparticles (NPs) including inorganic NPs, polymer NPs, lipid NP, extracellular vesicles and cell membrane-based NPs have been evaluated as the better DDS candidates that can specifically accumulate in the tumor microenvironment along with a large amount of blood vessels. Emerging evidence suggested that NPs formulated with anticancer drugs including chemotherapeutic drugs, radiotherapy and immunotarget antibodies could remarkably improve the release and increase concentration of these drugs at the tumor site and show a better therapeutic efficacy, suggesting that NPs might serve as promising DDSs in the treatment of OSCC. Therefore, we have conducted this review to summarize recent progression and current status of diverse NPs as DDSs in this research field.

3.
IET Nanobiotechnol ; 2023: 7971492, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38863476

RESUMO

Although quercetin is low cytotoxicity to normal human cells, quercetin is effective against the growth of some tumors. Given the poor blood stability in vivo, insolubility, low delivery efficiency, and poor medicinal properties of quercetin, we developed a local drug delivery system comprising quercetin core's polymer micelles and F127 hydrogel stroma. In vitro evaluation revealed that quercetin core's polymer micelles have excellent antitumor activity and could inhibit the multiplication of 4T1 breast cancer cells through the apoptosis pathway. Meanwhile, a rheological study revealed that the quercetin core's micelles gel possessed excellent properties of hydrogel formation and injectability of liquid preparation as a local drug delivery system after the quercetin core's polymer micelles were loaded into the F127 hydrogel stroma. Our study findings indicated that the drug stability and stable release capacity of quercetin were vastly improved with the composite formulation of the micelles gel. This not only realized drug injectability but also drug storage in the semisolid form, which is a more comfortable and slower drug-releasing form that will eventually exert a proper therapeutic effect. In conclusion, quercetin micellar hydrogel system has better antitumor activity and excellent hydrogel properties.


Assuntos
Antineoplásicos , Neoplasias da Mama , Micelas , Quercetina , Quercetina/química , Quercetina/farmacologia , Quercetina/farmacocinética , Quercetina/administração & dosagem , Linhagem Celular Tumoral , Camundongos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Antineoplásicos/farmacocinética , Antineoplásicos/administração & dosagem , Feminino , Sobrevivência Celular/efeitos dos fármacos , Humanos , Apoptose/efeitos dos fármacos , Hidrogéis/química
4.
Shanghai Kou Qiang Yi Xue ; 31(2): 184-188, 2022 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-36110077

RESUMO

PURPOSE: To observe the effect of non-bracket invisible appliance and self-locking bracket appliance on periodontal health and subgingival flora in patients with periodontitis. METHODS: One hundred and ten patients with periodontitis who received orthodontic treatment were divided into invisible group and self-locking bracket group. The periodontal index including probing depth (PD), gingival index (GI), sulcular bleeding index (SBI) and plaque index (PLI) ,and the levels of inflammatory factors in the gingival crevicular fluid were examined. Visual analogue scale (VAS) was used to evaluate periodontal pain before and after correction, and the curative effect was evaluated. The status of common pathogenic bacteria in the subgingival plaque of patients after correction was detected by PCR. The data were analyzed with SPSS19.0 software package. RESULTS: Twelve months after treatment and at the end of treatment, PLI of the self-locking bracket group was significantly higher than the invisible group(P<0.05), but PD, GI and SBI between the two groups had no significant difference. After correction, the inflammatory factors in the invisible group were significantly lower than those in the self-locking bracket group(P<0.05). At 1d after treatment, pain index in the invisible group was significantly lower than the self-locking group(P<0.05). The clinical total effective rate of the invisible group was significantly higher than the self-locking group (89.10% vs 76.36%). After treatment, the detection rate and the content of subgingival pathogenic bacteria in the self-locking bracket group were significantly higher than the invisible group(P<0.05). CONCLUSIONS: During orthodontic treatment of periodontitis, wearing non-bracket invisible appliance can effectively inhibit inflammatory response and proliferation of subgingival pathogens, which is more conducive to the maintenance of periodontal health and oral hygiene.


Assuntos
Placa Dentária , Periodontite , Índice de Placa Dentária , Líquido do Sulco Gengival , Humanos , Índice Periodontal , Periodontite/terapia
5.
Oxid Med Cell Longev ; 2022: 2312784, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36065438

RESUMO

Background: Peri-implant mucositis (PiM) is characterized as a reversible inflammatory change of the peri-implant soft tissues without alveolar bone loss or continuing marginal bone loss. Without proper control of PiM, the reversible inflammation may advance to peri-implantitis (PI). Mechanical debridement (MD) by the implant surface is the most common and conventional nonsurgical approach to treat PiM but with limitations in complete resolution of diseases. For more than a decade, chlorhexidine (CHX) and active compounds has been investigated in the treatment of PiM. Therefore, the aim of this systematic review and meta-analysis was to evaluate the efficacy of CHX treatment in combination with MD versus MD alone or MD+placebo in patients with PiM on their oral health problems. Methods: A search using electronic databases (Ovid MEDLINE, EMBASE, Science Direct databases, and Cochrane Central Register of Controlled Trials) and a manual search up to May 2022 were performed independently by 2 reviewers and included eligible randomized controlled trials (RCTs) comparing MD+CHX versus MD alone or MD+placebo. The assessment of quality for all the selected RCTs was conducted according to the Cochrane Handbook for Systematic Reviews of Interventions. Disease resolution of PiM (absence of BOP), IPPD reduction, IBOP% reduction, and PI% reduction after treatment as primary outcomes were selected as the primary outcomes. Weighted mean differences (WMD) and 95% confidence interval (CI) were for continuous outcomes, and odds ratio (OR) and 95% CI was for dichotomous outcomes using random effect models. This review is registered on the PROSPERO database (CRD42020221989). Results: After independent screening, nine eligible studies were included in this systematic review and meta-analysis. Meta-analysis showed OR of disease resolution between test and control groups amounted to 1.41 (95% CI (0.43, 4.65), P = 0.57, I 2 = 65%) not favoring adjunctive CHX treatment over MD alone. Through subgroup analysis, the results indicated that oral irrigation of CHX may have more benefits on the resolution of PiM. Similarly, CHX did not significantly improve IPPD reduction at both short-, medium-, and long-term follow-up. Only a short-term effect has been observed at IBOP% reduction (WMD = 13.88, 95% CI (10.94, 16.81), P < 0.00001, I 2 = 9%), IPI reduction (WMD = 0.12, 95% CI (0.09, 0.14), P < 0.00001, I 2 = 0%), and FMPPD reduction (WMD = 0.19 mm, 95% CI (0.03, 0.35), P = 0.02, I 2 = 0%) with adjunctive CHX application. Conclusion: Adjunctive CHX application may have some benefits to improve the efficacy of MD in PiM treatment by reducing IBOP%, IPI, and FMPPD in short-term. But these benefits disappeared at medium- and long-term follow-up. In order to achieve better disease resolution of PiM, adjunctive CHX irrigation with MD may be suggested and has positive potential. Well-designed large clinical trials are needed in future.


Assuntos
Mucosite , Peri-Implantite , Clorexidina/uso terapêutico , Humanos , Mucosite/tratamento farmacológico , Saúde Bucal , Peri-Implantite/tratamento farmacológico
6.
J Musculoskelet Neuronal Interact ; 22(2): 261-268, 2022 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-35642705

RESUMO

OBJECTIVES: MicroRNAs (miRNAs) have been considered as a new class of novel diagnostic and predictive biomarker in many diseases. However, there are few studies on miRNA in osteosarcoma (OS). This study aimed to investigate the roles of miR-30 on OS occurrence and development. METHODS: PCR was used to detect mRNA levels of miR-30 and MTA1 in cancer tissues, adjacent non-cancerous tissues from OS patients. Western blot was used to detect MTA1 protein expression in all tissues and cell lines (hFOb1.19,Saos-2, MG63, and U2OS). The correlation between miR-30 and MTA1 was predicted through bioinformatics software, and identified by a luciferase reporting experiment. In vitro, functional test detected the specific effects of miR-30 and MTA1 on the development of OS. RESULTS: miR-30 expression was significantly reduced, while the expression of MTA1 was increased in OS tissues and cells. Luciferase reporting experiment showed that miR-30 sponged MTA1 which was negatively correlated with miR-30 expression. Furthermore, rescue tests revealed that MTA1 restrained the functions of miR-30 on cell proliferation and migration of OS. CONCLUSION: Our finding showed that miR-30 modulated the proliferation and migration by targeting MTA1 in OS.


Assuntos
Neoplasias Ósseas , MicroRNAs , Osteossarcoma , Proteínas Repressoras , Transativadores , Neoplasias Ósseas/genética , Neoplasias Ósseas/metabolismo , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica , Humanos , MicroRNAs/genética , MicroRNAs/metabolismo , Osteossarcoma/genética , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo , Transativadores/genética , Transativadores/metabolismo
7.
Iran J Public Health ; 51(12): 2773-2782, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36742226

RESUMO

Background: Osteosarcoma is the most common primary malignant tumor of bone. Abnormal expression of S100A1 protein is closely related to the occurrence and development of malignant tumors. However, S100A1 in osteosarcoma has not been studied. Methods: All osteosarcoma tissues were collected from patients who received surgical therapy at the Affiliated Hospital of Inner Mongolia Medical University, China in 2020. QRT-PCR and western blot assays were used to detect the expression of S100A1 in osteosarcoma tissues and cells. The negative effect of S100A1 on osteosarcoma cell growth was confirmed by vitro and vivo experiments. Results: S100A1 inhibited the growth of osteosarcoma cells in vitro. Overexpression of S100A1 may inhibit the proliferation of osteosarcoma cells by preventing the activation of AKT signaling pathway by western blot assay. Finally, animal experiments confirmed that overexpression of S100A1 could inhibit the proliferation of osteosarcoma cells. Overexpression of S100A1 obtained better survival benefit in mice. Conclusion: Our findings provided a new insight to the treatment of osteosarcoma. It also raised the possibility that S100A1 could be used in targeted therapies for osteosarcoma.

8.
Am J Transl Res ; 13(9): 10094-10111, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650683

RESUMO

Cancer-associated fibroblasts (CAFs) serve as a predominant regulator in the tumor microenvironment. However, the crosstalk between CAFs and OS cells remains mostly unclear. Recent studies explored that long non-coding RNA (LncRNAs) involved in regulating osteosarcoma (OS) formation and development, but their functions in CAFs are unknown. Here, we first investigated the SNHG17 was upregulated in OS tissues and correlated with the poor prognosis through the integrating clinical data. We then evaluated the function of SNHG17 in vitro using the stable SNHG17-depleted OS cells. HOS cells with SNHG17 knocked down were performed to generate the OS xenograft model. Through immunohistochemistry assay and TUNEL apoptosis assay, the role of SNHG17 on OS development was assessed in vivo. We then examined the SNHG17 expression in exosomes derived from CAFs, normal fibroblasts (NFs), and tumor tissues from the OS clinical samples. The interaction among SNHG17, miR-2861, and MMP2 was predicted by bioinformatics analysis and identified by RIP and luciferase assays. The cell proliferation, migration, and apoptosis of SJSA-1 and HOS cells co-cultured with CAFs-derived exosomes were assessed by CCK-8 and colony formation assays. We found that SNHG17 was upregulated in the tumor tissues and presented a pro-tumorigenic effect on OS both in vitro and in vivo. It also was an essential exosomal cargo of CAFs and could affect OS cell proliferation and migration in vitro. CAFs-released exosomal SNHG17 acted as an essential molecular sponge for miR-2861 in OS cells. Moreover, MMP2 was a direct target of miR-2861 and was regulated by SNHG17. Overall, our findings identified that SNHG17 was an essential exosomal cargo of OS-related CAFs that contributes to proliferation and metastasis of OS, supporting the therapeutic potency of targeting the crosstalk between cancer cells and CAFs.

9.
Biosci Rep ; 41(2)2021 02 26.
Artigo em Inglês | MEDLINE | ID: mdl-33558879

RESUMO

BACKGROUND: Glycolysis was a representative hallmark in the tumor microenvironment (TME), and we aimed to explore the correlations between glycolysis with immune activity and clinical traits in bladder urothelial carcinoma (BLCA). METHODS: Our study obtained glycolysis scores for each BLCA samples from TCGA by a single-sample gene set enrichment analysis (ssGSEA) algorithm, based on a glycolytic gene set. The relationship between glycolysis with prognosis, clinical characteristics, and immune function were investigated subsequently. RESULTS: We found that enhanced glycolysis was associated with poor prognosis and metastasis in BLCA. Moreover, glycolysis had a close correlation with immune function, and enhanced glycolysis increased immune activities. In other words, glycolysis had a positive correlation with immune activities. Immune checkpoints such as IDO1, CD274, were up-regulated in high-glycolysis group as well. CONCLUSION: We speculated that in BLCA, elevated glycolysis enhanced immune function, which caused tumor cells to overexpress immune checkpoints to evade immune surveillance. Inhibition of glycolysis might be a promising assistant for immunotherapy in bladder cancer.


Assuntos
Glicólise , Neoplasias da Bexiga Urinária/imunologia , Ensaios Clínicos como Assunto , Bases de Dados Factuais , Humanos
10.
Int J Mol Med ; 47(2): 583-594, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33416181

RESUMO

Osteosarcoma (OS) is one of the most aggressive malignancies, accompanied by an elevated incidence and a decreased rate of healing. Recently, several long non­coding RNAs (lncRNAs) have been reported to be involved in OS progression. Although tumor suppressor candidate 7 (TUSC7) was reported as a novel lncRNA, little is known about its biological functions in OS. The present study was designed to explore whether TUSC7 was involved in the pathological development of OS using various methods, including hematoxylin and eosin staining, Cell Counting Kit­8 assay, colony formation assay and Transwell assay. The present study revealed that TUSC7 expression was downregulated in OS tissues and cell lines compared with in normal tissues and cell lines. Functionally, the current results revealed that overexpression of TUSC7 inhibited OS cell proliferation, migration and invasion, while promoting apoptosis in vitro and in vivo. Next, the subcellular distribution of TUSC7 was examined by nuclear/cytoplasmic RNA fractionation and reverse transcription­quantitative PCR. Mechanistic studies revealed that TUSC7 exerted its role by sponging microRNA (miR)­181a in OS cell lines. Ras association domain family member 6 (RASSF6) was confirmed as a target gene of miR­181a, and the expression levels of RASSF6 were negatively regulated by miR­181a. Additionally, the results of rescue experiments suggested that overexpression of miR­181a neutralized the inhibitory effects of TUSC7 overexpression on OS cells. Overall, the present study demonstrated that the tumor suppressor role of TUSC7 in OS progression was mediated through the miR­181a/RASSF6 axis, which may represent a new therapeutic target for OS.


Assuntos
Proteínas Reguladoras de Apoptose/metabolismo , Neoplasias Ósseas/metabolismo , Genes Supressores de Tumor , MicroRNAs/metabolismo , Proteínas de Neoplasias/metabolismo , Osteossarcoma/metabolismo , RNA Longo não Codificante/metabolismo , RNA Neoplásico/metabolismo , Transdução de Sinais , Adolescente , Adulto , Proteínas Reguladoras de Apoptose/genética , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Criança , Feminino , Humanos , Masculino , MicroRNAs/genética , Proteínas de Neoplasias/genética , Osteossarcoma/genética , Osteossarcoma/patologia , RNA Longo não Codificante/genética , RNA Neoplásico/genética
11.
Mol Clin Oncol ; 14(1): 17, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33363727

RESUMO

Chordoma is a sporadic type of cancer that affects the spine and is particularly challenging to treat due to the paucity of reported cases and scientific literature. In particular, primary chordomas affecting both the sacral and thoracic vertebrae are extremely rare. We herein report a rare case of chordoma in the sacral and thoracic vertebrae with pulmonary metastasis, along with a literature review. The objective of the present study was to explore treatment options and long-term outcomes in patients with metastatic chordoma. Posterior decompression was performed for the thoracic tumor, followed by extended resection of the sacral tumor. The symptoms of the patient were relieved after surgery, and the postoperative Nurick score decreased from grade 3 to grade 2, while the postoperative McCormick score was I. Therefore, complete chordoma excision and internal spinal fixation may effectively reduce tumor recurrence and metastasis.

12.
Drug Deliv ; 24(1): 1598-1604, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29043863

RESUMO

The main objective of this study was to develop a pH gradient release pellet with self-emulsifying drug delivery system (SEDDS), which could not only improve the oral bioavailability of Vinpocetine (VIN), a poor soluble drug, but reduce the fluctuation of plasma concentration. First, the liquid VIN SEDDS formulation was prepared. Then the self-emulsifying pH gradient release pellets were prepared by extrusion spheronization technique, and formulation consisted by the liquid SEDDS, absorbent (colloidal silicon dioxide), penetration enhancer (sodium chloride), microcrystalline cellulose, ethyl alcohol, and three coating materials (HPMC, Eudragit L30D55, Eudragit FS30D) were eventually selected. Three kinds of coated pellets were mixed in capsules with the mass ratio of 1:1:1. The release curves of capsules were investigated in vitro under the simulated gastrointestinal conditions. In addition, the oral bioavailability and pharmacokinetics of VIN self-emulsifying pH gradient release pellets, commercial tablets and liquid VIN SEDDS were evaluated in Beagle dogs. The oral bioavailability of self-emulsifying pH gradient release pellets was about 149.8% of commercial VIN tablets, and it was about 86% of liquid VIN SEDDS, but there were no significant difference between liquid SEDDS and self-emulsifying pH gradient release pellets. In conclusion, the self-emulsifying pH gradient release pellets could significantly enhance the absorption of VIN and effectively achieve a pH gradient release. And the self-emulsifying pH gradient release pellet was a promising method to improve bioavailability of insoluble drugs.


Assuntos
Química Farmacêutica/métodos , Fármacos Neuroprotetores/administração & dosagem , Fármacos Neuroprotetores/farmacocinética , Alcaloides de Vinca/administração & dosagem , Alcaloides de Vinca/farmacocinética , Administração Oral , Animais , Cães , Sistemas de Liberação de Medicamentos , Emulsificantes/química , Emulsões/química , Ácidos Polimetacrílicos , Força Próton-Motriz , Solubilidade
13.
Artigo em Inglês | MEDLINE | ID: mdl-24046598

RESUMO

In the title compound, C16H19ClN4O3, the cyclo-hexane ring displays a chair formation and the tetra-hydro-pyridine ring displays an envelope conformation with the methyl-ene C atom as the flap; the imidazolidine ring also displays an envelope conformation with a methyl-ene C atom as the flap. In the crystal, O-H⋯N hydrogen bonds between hy-droxy groups and pyridine rings link inversion-related mol-ecules into dimers. Weak C-H⋯O hydrogen bonds further link the dimers into supra-molecular chains running along the c axis.

14.
Microsc Res Tech ; 76(6): 612-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23580478

RESUMO

OBJECTIVE: Although several methods have been used to detect the intracellular reactive oxygen species (ROS) generation, it is still difficult to determine where ROS generate from. This study aimed to demonstrate whether ROS generate from mitochondria during oxidative stress induced mitochondria damage in cardiac H9c2 cells by laser scanning confocal microscopy (LSCM). METHODS: Cardiac H9c2 cells were exposed to H2 O2 (1200µM) to induce mitochondrial oxidant damage. Mitochondrial membrane potential (ΔΨm) was measured by staining cells with tetramethylrhodamine ethyl ester (TMRE); ROS generation was measured by staining cells with dichlorodihydrofluorescein diacetate (H2 DCFDA). RESULTS: A rapid/transient ROS burst from mitochondria was induced in cardiac cells treated with H2 O2 compared with the control group, suggesting that mitochondria are the main source of ROS induced by oxidative stress in H9c2 cells. Meanwhile, the TMRE fluorescence intensity of mitochondria which had produced a great deal of ROS decreased significantly, indicating that the burst of ROS induces the loss of ΔΨm. In addition, the structure of mitochondria was damaged seriously after ROS burst. However, we also demonstrated that the TMRE fluorescence intensity might be affected by H2 DCFDA. CONCLUSIONS: Mitochondria are the main source of ROS induced by oxidative stress in H9c2 cells and these findings provide a new method to observe whether ROS generate from mitochondria by LSCM. However, these observations also suggested that it is inaccurate to test the fluorescence intensities of cells stained with two or more different fluorescent dyes which should be paid more attention to.


Assuntos
Microscopia Confocal/métodos , Mitocôndrias/química , Mitocôndrias/fisiologia , Espécies Reativas de Oxigênio/análise , Explosão Respiratória , Animais , Linhagem Celular , Peróxido de Hidrogênio/toxicidade , Estresse Oxidativo , Ratos
15.
Drug Dev Ind Pharm ; 35(5): 603-11, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19040178

RESUMO

The main purpose of current investigation is to prepare a self-microemulsifying drug delivery system (SMEDDS) to enhance the oral bioavailability of vinpocetine, a poorly water-soluble drug. Suitable vehicles were screened by determining the solubility of vinpocetine in them. Certain surfactants were selected according to their emulsifying ability with different oils. Ternary phase diagrams were used to identify the efficient self-microemulsifying region and to screen the effect of surfactant/cosurfactant ratio (K(m)). The optimized formulation for in vitro dissolution and bioavailability assessment was oil (ethyl oleate, 15%), surfactant (Solutol HS 15, 50%), and cosurfactant (Transcutol P, 35%). The release rate of vinpocetine from SMEDDS was significantly higher than that of the commercial tablet. Pharmacokinetics and bioavailability of SMEDDS were evaluated. It was found that the oral bioavailability of vinpocetine of SMEDDS was 1.72-fold higher as compared with that of the commercial tablet. These results obtained demonstrated that vinpocetine absorption was enhanced significantly by employing SMEDDS. Therefore, SMEDDS might provide an efficient way of improving oral bioavailability of poorly water-soluble drugs.


Assuntos
Nootrópicos/administração & dosagem , Alcaloides de Vinca/administração & dosagem , Animais , Disponibilidade Biológica , Química Farmacêutica , Cães , Composição de Medicamentos , Sistemas de Liberação de Medicamentos , Emulsões , Excipientes , Nootrópicos/química , Nootrópicos/farmacocinética , Óleos/química , Tamanho da Partícula , Solubilidade , Tensoativos , Alcaloides de Vinca/química , Alcaloides de Vinca/farmacocinética
16.
Int J Pharm ; 356(1-2): 282-90, 2008 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-18289806

RESUMO

In the present study, novel less-painful tocol emulsions for the intravenous delivery of clarithromycin were prepared and optimized. The therapeutically effective concentration of clarithromycin, 5mg/ml, was achieved using tocopherol succinate (TS) combined with oleic acid as lipophilic counterions. The possibility of employing the microdialysis technique to investigate the distribution of the drug in emulsions was explored. A three-level three-factorial Box-Behnken experimental design was utilized to conduct the experiments. The effects of selected variables, tocopherol succinate/oleic acid relation, poloxamer 188 content and 0.1M NaOH amount, on three considered responses were investigated. The particle size, zeta potential and the oil phase distribution of clarithromycin for the optimized formulation were observed to be 138.5 nm, -32.16 mV and 97.28%, respectively. The emulsions prepared with the optimized formula demonstrated good physical stability during storage at 4 degrees C and room temperature. The histopathological examination for rabbit ear vein irritation test indicated that the irritation of clarithromycin could be eliminated by formulating the drug in a tocol emulsion.


Assuntos
Antibacterianos/administração & dosagem , Claritromicina/administração & dosagem , Excipientes/química , Vitamina E/análogos & derivados , Animais , Antibacterianos/efeitos adversos , Claritromicina/efeitos adversos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Emulsões , Infusões Intravenosas , Microdiálise , Ácido Oleico/química , Dor/induzido quimicamente , Tamanho da Partícula , Poloxâmero/química , Coelhos , Hidróxido de Sódio/química , Tocoferóis , Vitamina E/química
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