Hydroxypropyl methylcellulose (HPMC) propels self-emulsifying drug delivery systems (SEDDS) to achieve the supersaturated state in gastrointestinal tract, which possesses important significance to enhance oral absorption for poorly water-soluble drugs. This study investigated capacities and mechanisms of HPMC with different viscosities (K4M, K15M and K100M) to inhibit drug precipitation of SEDDS in the simulated gastrointestinal tract environment in vitro. The results showed that HPMC inhibited drug precipitation during the dispersion of SEDDS under gastric conditions by inhibiting the formation of crystal nucleus and the growth of crystals. HPMC had evident effects on the rate of SEDDS lipolysis and benefited the distribution of drug molecules across into the aqueous phase and the decrease of drug sediment. The mechanisms were related to the formed network of HPMC and its viscosities and molecular weight. These results offered a reference for selecting appropriate type of HPMC as the precipitation inhibitor of supersaturatable SEDDS.

A new dynamic in vitro intestinal absorption model for screening and evaluating lipid formulations was established by means of the characteristics of the intestinal digestion and absorption of the lipid formulations. This model was composed of two systems, including intestinal digestion and the intestinal tissue culture, which drew the evaluation method of intestinal absorption into the in vitro lipolysis model. The influence of several important model parameters such as Ca2+, D-glucose, K+ on the two systems of this model has been investigated. The results showed that increasing of Ca2+ concentration could be significantly conductive to intestinal digestion. The increasing of D-glucose concentration could stepped significantly down the decay of the intestinal activity. K+ was able to maintain intestinal activity, but the influence of different concentration levels on the decay of the intestinal activity was of no significant difference. Thus the model parameters were set up as follows: Ca2+ for 10 mmol x L(-1), D-glucose for 15 mmol x L(-1) and K+ for 5.5 mmol x L(-1). Type I lipid formulation was evaluated with this model, and there was a significant correlation between the absorption curve in vitro and absorption curve in vivo of rats (r = 0.995 6, P < 0.01). These results demonstrated that this model can be an attractive and great potential method for the screening, evaluating and predicting of the lipid formulations.

This paper report the development of a new dosage form - self-microemulsifying mouth dissolving films, which can improve the oral bioavailability of water insoluble drugs and have good compliance. A three factor, three-level Box-Behnken design was used for optimizing formulation, investigated the effect of amounts of microcrystalline cellulose, low-substituted hydroxypropyl cellulose and hypromellose on the weight, disintegration time, cumulative release of indomethacin after 2 min, microemulsified particle size and stretchability. Optimized self-microemulsifying mouth dissolving films could fast disintegrate in (17.09 +/- 0.72) s; obtain microemulsified particle size at (28.81 +/- 3.26) nm; and release in vitro at 2 min to (66.18 +/- 1.94)%. Self-microemulsifying mouth dissolving films with broad application prospects have good compliance, strong tensile and can be released rapidly in the mouth through fast self-microemulsifying.

Solid carriers had important effects on the properties of solid self-microemulsifying drug delivery systems (S-SMEDDS). In order to make the basis for further development of S-SMEDDS, the influences of silica on the absorption of S-SMEDDS were investigated. An in vitro lipolysis model was used to evaluate the influence of silica on self-microemulsifying drug delivery system digestion from intestinal tract. S-SMEDDS containing silica were prepared by extrusion/spheronization. The drug release and absorption were investigated. The results showed that lipolysis rate and drug concentration in aqueous phase after intestinal lipolysis both increased by adding silica, which was benefit to drug absorption. And silica was not benefit to absorption for slowing drug release. Consistently, there was no significant influence of silica on intestinal absorption. This study implied that the influences of silica on lipolysis rate and drug release were both amount dependent and it is suggested that silica could be used as the solid carrier but the proportion needs to be optimized.

The distribution fate and solubilization behavior of indomethacin through the intestinal tract were investigated with in vitro lipolysis model, by comparing the Capmul MCM and Labrafil M 1944 CS type I lipid formulations. The results showed that the more favorable solubilization was in the aqueous digestion phase from each lipid formulations for indomethacin. The lipolysis rate and extent were decided with chemical constitution of the lipid excipients, which meant that less indomethacin was transferred from the long chain polar oil lipid solution into the aqueous digestion phase. Increasing the concentration of indomethacin in the lipid formualitons from a solution to a suspension led to a linear increase in the concentration of indomethacin attained in the aqueous digestion phase from lipid formulations. This study also implied that adverse effects of the lipolysis rate and extent on drug absorption were could be taken into consideration when screening lipid formulations. Lipid suspensions likely had better enhancement of drug absorption. Last, this study demonstrated that a potential basis for optimizing and assessing type I lipid formulations and also researching in vivo-in vitro correlations of lipid formulations were provided by an in vitro lipolysis model.

Acute Kidney Injury ; chemically induced ; enzymology ; Animals ; Disease Models, Animal ; Gentamicins ; Peptidyl-Dipeptidase A ; metabolism ; Rats

Background Aspheric intraocular lens (IOL) is designed to reduce the spherical aberration of the eye after cataract surgery and to obtain better visual quality.However,the selection of a personalized aspheric IOL is a problem to be solved.Objective This study was to compare the wavefront aberration and quality of vision of patients between the implantation of negative spherical aberration IOL and non-aberration IOL,and to investigate the relationship between corneal Q values and postoperative spherical aberration.Methods One hundred and four eyes of 90 patients with age-related cataract were randomized into two groups.Fifty-two eyes of 46 patients who received a Tecnis Z9001 IOL implantation were assigned as the negative spherical aberration IOL group and 52 eyes of 44 patients who received Akreos AO IOL without aberration were assigned as the non-aberration IOL group.The preoperative corneal Q values were measured and the mean Q value(Q)was computed.Then the patients in the two groups were further divided into 2 subgroups,respectively,based on their Q values were over or below (Q）.The corneal Q values,root mean square(RMS) of ocular spherical aberration,coma and total higher-order aberrations(HOAs) for 5 mm diameter pupil,scotopic contrast sensitivity with or without glare at 6 mm pupil diameter were measured 3 months after surgery.Results The pre-and post-operative corneal Q values were insignificantly changed (t =1.447,P =0.151).The spherical aberration in the negative spherical aberration IOL group was(0.059-±0.047)μm,and that in the non-aberration IOL group was(0.110±0.066)μm,with a statistically significant difference between them (t =-4.567,P=0.000).Scotopic contrast sensitivities at intermediate and high frequencies were significantly better in the negative spherical aberration IOL group than in the non-aberration IOL group (t =2.495,t =2.359,P ＜ 0.05).There was no significant difference in coma and HOAs between the two groups after operation (P ＞ 0.05).Weak positive correlations were seen between the pre-and post-operative corneal Q values and spherical aberration in the two groups(r=0.277,0.292,0.285,0.325,all at P＜0.05).However,no significant differences were found in spherical aberration,contrast sensitivity and scotopic contrast sensitivity between the different subgroups (P ＞ 0.05).Conclusions Negative spherical aberration IOL has lower spherical aberration and better scotopic contrast sensitivity than non-aberration IOL.The results suggest that it may be not enough to choose the corneal Q value only as the single reference criterion for selection of aspheric IOL.

Objective To investigate the epidemiological characteristic of influenza in children in Guangzhou ,and provide the sci-entific basis for prevention .Methods A total of 20 throat swabs were collected from children with influenza-like illness(ILI) each week from 2014 to 2015 .A total of 2080 samples were obtained .The virus was isolated with MDCK cell line and virus type identi-fication were detected by real-time PCR .The relevant data was collected and analyzed epidemiologically .Results A total of 244 were detected positive in 2080 ILI cases in Guangzhou from 2014 to 2015 .The positive rate was 11 .7% .The positive rate of influ-enza virus reached peak in February and June in 2014 ,and the major type of influenza virus was new type H1N1 in February and H3N2 in June .The positive rate of influenza virus reached peak in March and June in 2015 ,and the major type of influenza virus were B type in March and H3N2 in June .Only one case of new H1N1 was detected in 2015 .The positive rate of influenza virus was 25 .6% in 3 to 6 years old ILI children which took larger part than other groups .Conclusion In Guangzhou ,the influenza virus epi-demic is more active in 2015 .The major type of influenza virus in the epidemic is seasonal type H 3N2 and B .Type A and type B appeared in the epidemic alternatively .The 3-6 year-old children are the high-risk group of influenza infection ,and should be monitored .

Objective To study the effects of cyclooxygenase-2(COX-2) selective inhibitor celecoxib on proliferation and apoptosis of human endometrial adenocarcinoma HEC-1B cell line. Methods Methabenzthiazuron(MTT) assay was used to examine the effects of different concentrations of celecoxib on proliferation of HEC-1B cells.When HEC-1B cells were treated with different concentrations of celecoxib for 24 h,cell cycle and apoptosis were detected by flow cytometry.The expression of COX-2 mRNA was analyzed by RT-PCR. Results MTT results indicated that celecoxib could inhibit HEC-1B cell proliferation in a time-and dose-dependent manner.When HEC-1B cells were treated with different concentrations of celecoxib for 24 h,flow cytometry results showed that the cell percent of(G_(0)/G_(1)) phase increased,S and G_(2)/M phase decreased,and cell apoptosis rate also increased,which was significantly different from that of the control group(P

Phthalate esters belong to the group of environmental hormones,which are ubiquitous environmental pollutants and they can damage the human health through breathing to get into the body.The recent researches on the analysis of phthalate esters in the air such as sampling,pretreatment and determination were reviewed and some related issues were discussed in the paper.It would be reference for the further study of phthalate esters.