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1.
Respirology ; 2024 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-39004954

RESUMO

BACKGROUND AND OBJECTIVE: Cytisine serves as an affordable smoking cessation aid with acceptable safety profile. However, data comparing its efficacy and safety to standard therapies are limited. We aimed to examine efficacy and safety of cytisine compared to nortriptyline, which is the only approved smoking-cessation medication in Thailand. METHODS: A 12-month, multicentre, randomized, double-blinded, placebo-controlled trial was conducted. Participants aged ≥20 years who smoked ≥10 cigarettes/day were randomly assigned to receive a 25-day cytisine or a 12-week nortriptyline treatment course. Brief interventions (BI) for smoking cessation were provided to all participants. The primary outcome was biochemically verified continuous abstinence rate (CAR) at 12 months. Additionally, self-reported abstinence, verified by exhaled carbon monoxide (CO) ≤ 10 ppm, was collected at 2 weeks, 1, 3, 6 and 12 months to assess both CAR and 7-day point prevalence abstinence rate (PAR). RESULTS: A total of 1086 participants were recruited and randomized into cytisine (n = 540) and nortriptyline (n = 546) groups. The 12-month CAR was 12.22% for cytisine and 9.52% for nortriptyline. The relative difference was 0.03 (95% confidence interval [CI]; -0.01 to 0.06) and the relative risk was 1.28 (95% CI; 0.91-1.81). No differences were observed in secondary outcomes between both groups. The incidence of adverse effects from cytisine appeared to be lower than that of nortriptyline. CONCLUSION: At 12 months, cytisine plus BI was as effective as nortriptyline plus BI for smoking cessation. The adverse events for both cytisine and nortriptyline were minimal and well-tolerated.

2.
AAPS PharmSciTech ; 17(2): 427-35, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26206402

RESUMO

Amodiaquine dihydrochloride monohydrate (AQ-DM) was obtained by recrystallizing amodiaquine dihydrochloride dihydrate (AQ-DD) in methanol, ethanol, and n-propanol. Solid-state characterization of AQ-DD and AQ-DM was performed using X-ray powder diffractometry, Fourier transform infrared spectroscopy, thermogravimetry, and differential scanning calorimetry. All recrystallized samples were identified as AQ-DM. Crystal habits of AQ-DD and AQ-DM were shown to be needle-like and rhombohedral crystals, respectively. When AQ-DD and AQ-DM were exposed to various relative humidity in dynamic vapor sorption apparatus, no solid-state interconversion was observed. However, AQ-DM showed higher solubility than AQ-DD when exposed to bulk water during solubility study, while excess AQ-DM was directly transformed back to a more stable AQ-DD structure. Heating AQ-DM sample to temperatures ≥190°C induced initial change to metastable amorphous form (AQ-DA) which was rapidly recrystallized to AQ-DD upon ≥80%RH moisture exposure. AQ-DD was able to be recrystallized in alcohols (C1-C3) as AQ-DM solid-state structure. In summary, AQ-DM was shown to have different solubility, moisture and temperature stability, and interconversion pathways when compared to AQ-DD. Thus, when AQ-DM was selected for any pharmaceutical applications, these critical transformation and property differences should be observed and closely monitored.


Assuntos
Amodiaquina/química , Etanol/química , 1-Propanol/química , Varredura Diferencial de Calorimetria/métodos , Cristalização , Estabilidade de Medicamentos , Umidade , Metanol/química , Pós/química , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Temperatura , Água/química , Difração de Raios X/métodos
3.
Pharm Res ; 32(7): 2458-73, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25673042

RESUMO

PURPOSE: Raman spectroscopy is potentially an extremely useful tool for the understanding of drug-polymer interactions in solid dispersions. This is examined and demonstrated for the case of solid dispersions of nifedipine in a polymeric substrate. METHODS: Solid dispersions consisting of nifedipine and polyvinyl caprolactam--polyvinyl acetate--polyethylene glycol graft copolymer (Soluplus®) were prepared by freeze drying, melting and solvent evaporation at drug loadings of 10, 30, 50, 70 and 90% w/w. Drug-polymer interactions in the amorphous solid dispersion were estimated by Raman spectroscopy. The correlation between the solid state stability of the drug in a solid dispersion and the extent of drug-polymer interaction was monitored by X-ray diffractometry. RESULTS: The miscibility limit of nifedipine-Soluplus® was found to be 30% w/w drug loading for all preparation methods. The drug was found to interact with Soluplus®, through a hydrophilic interaction identified by infrared spectroscopy and a hydrophobic interaction which could be quantified by Raman spectroscopy. The average extent of the drug-polymer interaction in the studied amorphous samples at equivalent drug loading was similar, regardless of the preparation method. Inhomogeneities in samples prepared by melting contributed to a wider variation in drug-polymer interaction and poorer solid state stability, in terms of its crystallization tendency. CONCLUSIONS: Raman spectroscopy was shown to be a useful technique in classifying miscibility levels based on the hydrophobic interaction between the drug and the polymer. Different drug loadings showed varying degrees of drug-polymer interaction, and hence variable solid state stability of the solid dispersion.


Assuntos
Bloqueadores dos Canais de Cálcio/química , Excipientes/química , Nifedipino/química , Polietilenoglicóis/química , Polivinil/química , Análise Espectral Raman , Cristalização , Composição de Medicamentos , Interações Medicamentosas , Estabilidade de Medicamentos , Modelos Químicos , Estrutura Molecular , Transição de Fase , Solubilidade
4.
Int J Dent ; 2022: 6437200, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35310461

RESUMO

Vitamin C is essential for wound healing. However, there are no reports concerning the effect of a different dose of vitamin C on extraction wound size clinically. Therefore, the aim of this study was to investigate the effect of different oral vitamin C doses on extraction wound healing. A split-mouth, double-blind randomized clinical trial was performed in 42 patients who underwent symmetric bilateral noninfected premolar extraction. The patients were randomly divided into 3 groups, namely, P/600, P/1,500, and 600/1,500 (14 patients for each group); P/600: placebo vs. 600 mg vitamin C/d, P/1,500: placebo vs. 1,500 mg vitamin C/d, and 600/1,500: 600 mg vitamin C/d vs. 1,500 mg vitamin C/d. Patients were prescribed placebo or/and vitamin C three times a day for 10 days after each tooth extraction. Extraction wound size and pain score were evaluated. The wound assessment was performed on day 0, 7, and 21; and then the tooth on the other side was extracted using the same protocol. Pain score was recorded on the first three days after extraction. The reduced size of mesiodistal extraction wound in percentage reduction between day 0 and 7 of teeth receiving vitamin C 600 mg/d was more than that in placebo (P < 0.05). Pain scores on day 1-3 of teeth receiving vitamin C 600 mg/d were significantly lower than the placebo side (P < 0.05). Taking oral vitamin C 600 mg/d over three doses for 10 days after tooth extraction enhances extraction wound healing by reducing mesiodistal extraction wound and reduces postoperative pain.

5.
Sci Rep ; 10(1): 14753, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32901085

RESUMO

Cyanthillium cinereum (L.) H.Rob. is one of the most popular herbal smoking cessation aids currently used in Thailand, and its adulteration with Emilia sonchifolia (L.) DC. is often found in the herbal market. Therefore, the quality of the raw material must be considered. This work aimed to integrate macro- and microscopic, chemical and genetic authentication strategies to differentiate C. cinereum raw material from its adulterant. Different morphological features between C. cinereum and E. sonchifolia were simply recognized at the leaf base. For microscopic characteristics, trichome and pappus features were different between the two plants. HPTLC profiles showed a distinct band that could be used to unambiguously differentiate C. cinereum from E. sonchifolia. Four triterpenoid compounds, ß-amyrin, taraxasterol, lupeol, and betulin, were identified from the distinct HPTLC band of C. cinereum. The use of core DNA barcode regions; rbcL, matK, ITS and psbA-trnH provided species-level resolution to differentiate the two plants. Taken together, the integration of macroscopic and microscopic characterization, phytochemical analysis by HPTLC and DNA barcoding distinguished C. cinereum from E. sonchifolia. The signatures of C. cinereum obtained here can help manufacturers to increase the quality control of C. cinereum raw material in commercialized smoking cessation products.


Assuntos
Asteraceae/classificação , Asteraceae/genética , Cromatografia Líquida de Alta Pressão/métodos , Código de Barras de DNA Taxonômico/métodos , DNA de Plantas/análise , Análise de Sequência de DNA/métodos , DNA de Plantas/genética , Abandono do Hábito de Fumar , Especificidade da Espécie
6.
Artigo em Inglês | MEDLINE | ID: mdl-31641366

RESUMO

Phikud Navakot (PN) is nine major herbs in a famous traditional Thai recipe namely "Yahom Navakot" used to treat cardiovascular disorders. This study investigated the cardioprotective effects of PN formula on isoproterenol-induced myocardial infarction (IMI) in Sprague-Dawley rats. Forty-five rats were randomly divided into nine groups (n = 5 per group): the control, the IMI, the IMI + propranolol, the control or the IMI + PN formula (PN ethanolic extract at doses of 64, 127, or 255 mg/kg) by oroesophageal gavage for 28 days. The ST segment and serum troponin T levels were significantly increased in IMI rats. PN did not eliminate tissue necrosis, infiltration of inflammatory cells, or interstitial edema in IMI rats. All doses of PN decreased (p < 0.001) serum TNF-α and IL-6 levels. PN (127 and 255 mg/kg) up-regulated (p < 0.05) heme oxygenase (HO)-1 expression, whereas PN (255 mg/kg) significantly increased superoxide dismutase (SOD) 1 and 2 expression, compared with IMI rats. Nuclear factor erythroid 2-related factor 2 (Nrf2) and HO-1 expression significantly increased in IMI rats and IMI rats that received PN. PN formula possesses potential anti-inflammatory and antioxidant properties by modulating the levels of TNF-α, IL-6 and antioxidant enzymes. Our study reveals a novel cardioprotective effect of PN in IMI rats through the Nrf2/HO-1 signaling.

7.
J Pharm Sci ; 97(1): 473-89, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17924417

RESUMO

This work is focused on characterizing and evaluating the solid state interconversion of norfloxacin (NF) hydrates. Four stoichiometric NF hydrates, dihydrate, hemipentahydrate, trihydrate, pentahydrate and a disordered NF state, were generated by various methods and characterized by X-ray powder diffractometry (XRPD), thermal analysis and Karl Fisher titrimetry. XRPD patterns of all NF hydrates exhibited crystalline structures. NF hydrate conversion was studied with respect to mild elevated temperature and various degrees of moisture levels. NF hydrates transformed to anhydrous NF Form A after gentle heating at 60 degrees C for 48 h except dihydrate and trihydrate where mixture in XRPD patterns between anhydrous NF Form A and former structures existed. Desiccation of NF hydrates at 0% RH for 7 days resulted in only partial removal of water molecules from the hydrated structures. The hydrated transitional phase and the disordered NF state were obtained from the incomplete dehydration of NF hydrates after thermal treatment and pentahydrate NF after desiccation, respectively. Anhydrous NF Form A and NF hydrates transformed to pentahydrate NF when exposed to high moisture environment except dihydrate. In conclusion, surrounding moisture levels, temperatures and the duration of exposure strongly influenced the interconversion pathways and stoichiometry of anhydrous NF and its hydrates.


Assuntos
Antibacterianos/química , Norfloxacino/química , Antibacterianos/administração & dosagem , Fenômenos Químicos , Físico-Química , Cromatografia Líquida de Alta Pressão , Análise Diferencial Térmica , Composição de Medicamentos , Estabilidade de Medicamentos , Umidade , Indicadores e Reagentes , Microscopia Eletrônica de Varredura , Norfloxacino/administração & dosagem , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Comprimidos , Água/química , Difração de Raios X
8.
AAPS PharmSciTech ; 7(1): E12, 2006 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-16584142

RESUMO

The purpose of this research was to prepare spray-dried mucoadhesive microspheres for nasal delivery. Microspheres composed of hydroxypropyl methylcellulose (H), chitosan (CS), carbopol 934P (CP) and various combinations of these mucoadhesive polymers, and maltodextrin (M), colloidal silicon dioxide (A), and propylene glycol (P) as filler and shaper, were prepared by spray-drying technique. Using propranolol HCl as a model drug, microspheres were prepared at loadings exceeding 80% and yields between 24% and 74%. Bulky, free flowing microspheres that had median particle size between 15 and 23 mum were obtained. Their zeta potential was according to the charge of polymer. Adhesion time of mucoadhesive microspheres on isolated pig intestine was ranked, CS > CP:H > CP > H, while the rank order of swelling was CP > CS > H. Increasing the amount of CP in CP:H formulations increased the percentage of swelling. Infrared (IR) spectra showed no interaction between excipients used except CS with acetic acid. The release of drug from CP and CP:H microspheres was slower than the release from H and CS microspheres, correlated to their viscosity and swelling. Long lag time from the CP microspheres could be shortened when combined with H. The permeation of drug through nasal cell monolayer corresponded to their release profiles. These microspheres affected the integrity of tight junctions, relative to their swelling and charge of polymer. Cell viability was not affected except from CS microspheres, but recovery could be obtained. In conclusion, spray-dried microspheres of H, CS, CP, and CP:H could be prepared to deliver drug through nasal cell monolayer via the opening of tight junction without cell damaging.


Assuntos
Sistemas de Liberação de Medicamentos , Microesferas , Mucosa Nasal/metabolismo , Acrilatos/administração & dosagem , Adesividade , Administração Intranasal , Transporte Biológico , Células Cultivadas , Quitosana/administração & dosagem , Humanos , Derivados da Hipromelose , Metilcelulose/administração & dosagem , Metilcelulose/análogos & derivados , Nariz/citologia , Tamanho da Partícula , Solubilidade , Espectroscopia de Infravermelho com Transformada de Fourier , Junções Íntimas/efeitos dos fármacos
9.
AAPS PharmSciTech ; 7(1): E79-E88, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28290027

RESUMO

The purpose of this research was to prepare spray-dried mucoadhesive microspheres for nasal delivery. Microspheres composed of hydroxypropyl methylcellulose (H), chitosan (CS), carbopol 934P (CP) and various combinations of these mucoadhesive polymers, and maltodextrin (M), colloidal silicon dioxide (A), and propylene glycol (P) as filler and shaper, were prepared by spray-drying technique. Using propranolol HCl as a model drug, microspheres were prepared at loadings exceedings 80% and yields between 24% and 74%. Bulky, free flowing microspheres that had median particle size between 15 and 23 µm were obtained. Their zeta potential was according to the charge of polymer. Adhesion time of mucoadhesive microspheres on isolated pig intestine was ranked, CS>CP: H>CP>H, while the rank order of swelling was CP>CS>H. Increasing the amount of CP in CP∶H formulations increased the percentage of swelling. Infrared (IR) spectra showed no interaction between excipients used except CS with acetic acid. The release of drug from CP and CP∶H microspheres was slower than the release from H and CS microspheres, correlated to their viscosity and swelling. Long lag time from the CP microspheres could be shortened when combined with H. The permeation of drug through nasal cell monolayer corresponded to their release profiles. These microspheres affected the integrity of tight junctions, relative to their swelling and charge of polymer. Cell viability was not affected except from CS microspheres, but recovery could be obtained. In conclusion, spray-dried microspheres of H, CS, CP, and CP∶H could be prepared to deliver drug through nasal cell monolayer via the opening of tight junction without cell damaging.

10.
AAPS PharmSciTech ; 5(2): e30, 2004 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-15760088

RESUMO

Composite particles of rice starch (RS) and microcrystalline cellulose were fabricated by spray-drying technique to be used as a directly compressible excipient. Two size fractions of microcrystalline cellulose, sieved (MCS) and jet milled (MCJ), having volumetric mean diameter (D50) of 13.61 and 40.51 microm, respectively, were used to form composite particles with RS in various mixing ratios. The composite particles produced were evaluated for their powder and compression properties. Although an increase in the microcrystalline cellulose proportion imparted greater compressibility of the composite particles, the shape of the particles was typically less spherical with rougher surface resulting in a decrease in the degree of flowability. Compressibility of composite particles made from different size fractions of microcrystalline cellulose was not different; however, using MCJ, which had a particle size range close to the size of RS (D50 = 13.57 microm), provided more spherical particles than using MCS. Spherical composite particles between RS and MCJ in the ratio of 7:3 (RS-MCJ-73) were then evaluated for powder properties and compressibility in comparison with some marketed directly compressible diluents. Compressibility of RS-MCJ-73 was greater than commercial spray-dried RS (Eratab), coprocessed lactose and microcrystalline cellulose (Cellactose), and agglomerated lactose (Tablettose), but, as expected, lower than microcrystalline cellulose (Vivapur 101). Flowability index of RS-MCJ-73 appeared to be slightly lower than Eratab but higher than Vivapur 101, Cellactose, and Tablettose. Tablets of RS-MCJ-73 exhibited low friability and good self-disintegrating property. It was concluded that these developed composite particles could be introduced as a new coprocessed direct compression excipient.


Assuntos
Celulose , Amido , Química Farmacêutica , Excipientes , Microscopia Eletrônica , Oryza , Tecnologia Farmacêutica/métodos
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