Including preparation of cinnamon oil by vinyl pyrrolidone/vinyl acetate copolymer VA64-Soluplus spray-dried microspheres / 中草药

Objective: To investigate the applicability of the spray-dried microspheres of vinyl pyrrolidone/vinyl acetate copolymer VA64-Soluplus for inclusion of cinnamon oil (CO) and compare with traditional inclusion technology of β-cyclodextrin. Methods: HPLC was used to determine the encapsulation rate of inclusion complex. Transmission electron microscopy (TEM), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and X-ray powder diffraction (XRD) were used to characterize the inclusion complex; The dissolution and stability of the inclusion complex was investigated by in vitro release test and accelerated stability test; The pharmacokinetic and analgesic efficacy tests were used to examine the bioavailability and efficacy of the inclusion complex. Results: The encapsulation rate of microsphere inclusion complex and β-cyclodextrin inclusion complex was (98.38 ± 0.30)% and (86.51 ± 0.52)%, respectively. Observation of the inclusion complex under TEM showed a uniform spherical-like structure with uniform dispersion; Observation under SEM showed that the inclusion complex was spherical with a concave surface; The endothermic peak of volatile oil of cinnamon in DSC and the diffraction peak in XRD disappeared. The cinnamon volatile oil was dispersed in theinclusion complex in the form of non-aggregation; The cumulative release rates of cinnamon volatile oil, microsphere inclusion complex and β-cyclodextrin inclusion complex in in vitro dissolution experiments were 97.05%, 93.36% and 80.26%, respectively; Accelerated stability test at 60 ℃ showed that the loss rate of volatile oil of microsphere inclusion complex was significantly lower than that of cinnamon volatile oil and β-cyclodextrin inclusion complex; Pharmacokinetics showed that the AUC0-∞ of cinnamon essential oil, microsphere inclusion complex and β-cyclodextrin inclusion complex were basically the same; Pharmacodynamics showed that the analgesic rates of cinnamon volatile oil in the three groups were 53.0%, 47.5% and 21.1%, respectively. Conclusion: The stability of cinnamon volatile oil was enhanced by the combination of spray-dried microspheres of vinyl pyrrolidone/vinyl acetate copolymer VA64-Soluplus. The in vitro release, bioavailability and analgesic efficacy of microsphere were basically consistent with the volatile oil of cinnamon volatile oil, and it was superior to the inclusion compound of β-cyclodextrin. The vinyl pyrrolidone/vinyl acetate copolymer VA64-Soluplus microsphere inclusion compound had better water solubility. This study provides a new method for the inclusion of volatile oil.

Simultaneous Determination of Furan and Vinyl Acetate in Vapor Phase of Mainstream Cigarette Smoke by GC-MS

ABSTRACT A simple and sensitive method for simultaneous determination of furan and vinyl acetate (VA) in vapor phase of mainstream cigarette smoke with cold trap and gas chromatography-mass spectrometry (GC-MS) was developed. A Cambridge filter pad (CFP) was placed in front of the impingers of smoking machine to remove the particle phase from cigarette smoke. Furan and VA in vapor phase of mainstream cigarette smoke were collected in two impingers connected in series by filled with methanol at -78°C. The solutions were added with deuterium-labeled furan-d4 and VA-d6 as internal standards and analyzed by GC-MS. The results showed that the calibration curves for furan and VA were linear (r2 > 0.9995) over the studied concentration range. The intra- and inter-day precision values for furan and VA were <7.07% and <9.62%, respectively. The extraction recoveries of furan and VA were in the range of 94.5-97.7% and 92.3-94.9%, respectively. Moreover, the limits of detection for furan and VA were 0.028 µg mL-1 and 1.3 ng mL-1, respectively. The validated method has been successfully applied to determine the emissions of furan and VA in the vapor phase of mainstream cigarette smoke under International Organization for Standardization (ISO) and Canadian Intense (CI) smoking regimen.

Novo biomaterial composto de EVA (polietileno-co acetato de vinila) para enxerto "onlay" em tecido ósseo / New biomaterial composed of EVA (polyethylene-co-vinyl acetate) for onlay grafting in bone tissue

Introdução: o EVA (polietileno-co acetato de vinila) é um tipo de espuma, com baixo custo e ampla gama de aplicações. Misturas de EVA e amido proporcionam diferentes tipos de estrutura porosa favorecendo seu uso como scaffold para regeneração tecidual óssea. Objetivo: resultados prévios mostraram reação tecidual favorável ao seu uso como biomaterial, sendo assim, os mesmos foram investigados para fins de regeneração óssea. Método: nesse trabalho, 22 ratos linhagem Wistar foram divididos em dois grupos (4 destinados ao experimento piloto e 18 destinados ao projeto). Primeiramente, 4 animais foram submetidos à cirurgia na calota craniana para en xerto onlay em tecido ósseo dos biomateriais: 1) EVA com amido a 15% espumado em alta pressão com ultrassom (EVAMCU), 2) EVA espumado em alta pressão com ultrassom (EVACU), 3) EVA espumado em alta pressão sem ultrassom (EVASU), 4) EVA com amido a 15% espumado em alta pressão sem ultrassom (EVAMSU). Após 30 dias do pós-operatório, os biomateriais EVACU e EVAMCU apresentaram resultados microscópicos com fibrovascularização favorável e bom desempenho. Em sequência, 18 ratos foram submetidos à cirurgia de enxerto e após 7, 14 e 90 dias, 6 animais foram submetidos à eutanásia para coleta dos biomateriais e tecidos adjacentes da calota craniana. Foi realizada análise qualitativa da região de fibrovascularização, bem como do possível potencial osteogênico da região ao redor dos biomateriais ao longo dos períodos. Resultados e Conclusão: os biomateriais testados demonstraram biocompatibilidade e capacidade para regeneração óssea, no entanto, mais estudos precisam ser realizados, como por exemplo, em defeitos ósseos bicorticais.

Introduction: the EVA (polyethylene-co-vinyl acetate) is a kind of foam with low cost and wide range of applications. EVA and starch mixtures provide different types of porous structure favoring its use as scaffold for bone tissue regeneration. Objective: Previous results showed tissue reaction favorable to its use as biomaterial, and thus, they were investigated for purposes of bone regeneration. Method: in this study, 22 male Wistar rats were divided into two groups, 4 of them for the pilot experiment and 18 for the project. First, 4 animals underwent surgery on the skull cap for onlay graft in bone tissue of the biomaterials: 1) EVA with starch to 15% foamed at high pressure with ultrasound, 2) EVA foam at high pressure with ultrasound, 3) EVA foam for high pressure without ultrasound, 4) EVA with 15% starch foamed at high pressure without ultrasound). The results were evaluated microscopically 30 days after surgery and the biomaterials EVACU and EVAMCU presented good performance with favorable fibrovascularization. Eighteen rats were submitted to graft surgery and after 7, 14 and 90 days, 6 animals were submitted to euthanasia for the collection of biomaterials and adjacent tissues of the skullcap. A qualitative analysis of the region of fibro vascularization was performed, as well as the potential osteogenic based on the microscopic findings of the region surrounding the biomaterials throughout the periods. Results and Conclusion: the biomaterials tested demonstrated biocompatibility and capacity for bone regeneration, however, more studies need to be performed, for example, on bicortical bone defects.

Umbrales para las clases específicas de carcinógenos genotóxicos. nueva estrategia para la categorización de la carcinogenicidad de las sustancias químicas / Thresholds for specific classes of genotoxic carcinogens: a new strategy for carcinogenicity categorisation of chemicals

Cada vez está más claro el principio general de la secuencia de acontecimientos que finalmente conducen al cáncer después de la exposición a carcinógenos genotóxicos. Esto ayuda a conocer los parámetros que influyen en la forma de la curva dosis-efecto para la carcinogénesis, que incluyen activación e inactivación metabólica de carcinógenos, reparación del ADN, control del ciclo celular, proliferación regenerativa, apoptosis, senescencia inducida por oncogenes y control por el sistema inmunitario. Una relación lineal dosis-respuesta sin umbral observable parece ser una descripción conservadora pero adecuada para la actividad carcinógena de muchos carcinógenos genotóxicos, por ejemplo, la aflatoxina B1. Sin embargo, algunos modelos de extrapolación lineal que conectan el riesgo de alto nivel a la intersección en el cero han conducido a predicciones erróneas. En esta revisión se demuestra que el acetato de vinilo es un ejemplo de carcinógeno que actúa a través de un mecanismo de umbral. En los tejidos de contacto, el acetato de vinilo es convertido en ácido acético y acetaldehído. Sólo cuando se alcanzan las concentraciones umbral se activa el mecanismo que finalmente conduce al cáncer, es decir una reducción del pH mayor de 0.15 unidad que conduce a citotoxicidad, daño del ADN y proliferación regenerativa. En esta revisión se presenta un nuevo sistema de categorización de los carcinógenos que tiene en cuenta que pueden actuar por mecanismos de umbral.

The general principle of the sequence of events that finallylead to cancer after exposure to genotoxic carcinogenshas become increasingly clear. This helps to understandthe parameters that influence the shape of the dose effectcurve for carcinogenesis, including metabolic activationand inactivation of carcinogens, DNA repair, cell cyclecontrol, regenerative proliferation, apoptosis, oncogeneinducedsenescence and control by the immune system.A linear dose response relationship with no observablethreshold seems to be a conservative but adequatedescription for the carcinogenic activity of many genotoxiccarcinogens, such as for instance aflatoxin B1. However,some linear extrapolation models connecting the highlevelrisk to the zero intercept have resulted in wrongpredictions. In this review we demonstrate that vinylacetate is an example of a carcinogen acting by athreshold mechanism. In tissues of contact vinyl acetateis converted to acetic acid and acetaldehyde. Only whenthreshold levels are achieved critical steps in themechanism that ultimately leads to cancer become active,namely pH reduction of more than 0.15 units leadingto cytotoxicity, damage to DNA and regenerativeproliferation. In this review we present a new system ofcarcinogen categorisation taking into account thatcarcinogens may act by threshold mechanisms.

High dose exposures of vinyl acetate induce neoplastic transformation of human epithelial cells in culture

Vinyl acetate has been widely used for the manufacture of polyvinyl alcohol emulsion, which is primary ingredient of adhesive, paints, textile, paperboard coatings, etc. Since these products are plentiful and frequently used around us, workers and consumers are at health risk. International Agency for Research on Cancer (IARC) classified vinyl acetate as group 2B (possibly carcinogenic to humans). Among the organs targeted, the oral cavity is the most vulnerable organ affected by the carcinogenic effects of vinyl acetate. Since the origin of most of oral cancer is derived from the epithelial cells, it is important to understand the carcinogenic potential of vinyl acetate in human epithelial cells. Thus, the present study has attempted to utilize the immortalized human epithelial cell model to assess the carcinogenic potency of this chemical and to understand the underlying mechanisms.

Slow-release local drug delivery effect of tetracycline loaded calcium sulfate / 대한치주과학회지

Periodontal disease is a bacterially caused by disease. To remove plaque and bacteria, it has been necessary to prescribe chemical drug to patient to subjugate therapeutic unvalue by mechanical scaling. As a patient on a high dosage of the antibiotics to maintain the effective concentration may produce unfavorable side effects, this decase demands the Slow-release local drug delivery system. The object of the experiment is to study on the slow-release local drug delivery effects of calcium sulfate compounded with tetracycline that mainly used in periodontal disease. Experimental groups were divided into four classes as follow: Group 1 : 10% tetracycline compounded modified calcium sulfate paste. Group 2 : compounded and hardened 10% tetracycline and calcium sulfate. Group 3 : compounded 10% tetracycline and calcium sulfate, used just before hardened. Group 4 : tetracycline-ethylene vinyl acetate fiber. In the four groups, release concentration, it's durability and the period of absorption by times are observed and concluded as follow: 1. An effective concentration(4microgram/ml) remained until 5 weeks in group 1, 9 days in group 2, 7 days in group 3, 15 days in group 4. 2. It was fully fused at 11.8 days average in group 2 and 14.8 days average in group 3. 3. There were no statistically significant results in tetracycline concentration until a week in group 2 and 3(p<0.05) These results suggest that tetracycline loaded calcium sulfate release sufficient tetracycline and fused in 11~14 days, so calcium sulfate is useful carrier as slow release local drug delivery system

Observation on the absorption of EVA and PVC infusion sets to insulin / 肠外与肠内营养

Objective: To investigate the absorption of EVA and PVC infusion sets to insulin.Methods: Two infusion sets of EVA and PVC were used to contain insulin which was mixed with TNA and preserved at 4℃ and 25℃ for o,8,24 and 48 h,respectively.The content of insulin was observeed for changes.Results: The content of insulin mixed with TNA in EVA bags was obviously higher than in PVC bags preserved at 25℃ for 48h(P