1.Mechanisms of hydroxypropyl methylcellulose for the precipitation inhibitor of supersaturatable self-emulsifying drug delivery systems.
Acta Pharmaceutica Sinica 2013;48(5):767-72
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.
2.Clinical Features of Epidemic Cerebrospinal Meningitis of Children in Shanghai Area during 2006 to 2008
Journal of Applied Clinical Pediatrics 2006;0(22):-
Objective To investigate the epidemiology and clinical features of epidemic cerebrospinal meningitis of children in Shanghai area in the last 2.5 years. Methods A retrospective study was conducted in 27 hospitalized patients with epidemic cerebrospinal meningitis by analyzing the clinical manifestation,epidemiology and laboratory test fingdings from Jan.2006 to Jun.2008.Statistical analysis of the clinical manifestations of cases in serogroup A,B and C was performed according to Neisseria meningitidis infection. Results There were sporadic cases of children with epidemic cerebrospinal meningitis in Shanghai area in the last 2.5 years.The seasonal distribution illustrated the peak occurrence from Feb.to Apr.Among all these cases,92.6% were floating children.Common types(74.1%) were the predominant clinical manifestations and the others were fulminate types(25.9%).Four cases in each of serogroup A and B,and 8 cases of serogroup C were identified by serotyping on 14 Neisseria meningitidis strains and genotyping on the other 2 cases′ cerebrospinal fluid specimens.All the patients in serogroup A with meningococcal diseases were not vaccinated before and 25.0% of them belonged to fulminate types.Half of the cases had petechia on the skin and the prevalence of skin necrosis was 25.0% and 50% had complications of nervous system.No fulminate type was present in cases of serogroup B meningococcal disease and only 1 case had slight petechia on the skin.However,intensive convulsions occurred in 75.0% of the patients,and all of them had complication of nervous system,with a few had sequela.Among the patients in serogroup C meningococcal disease,62.5% patients were vaccinated with serogroup A Neisseria meningitidis.In serogroup C,Neisseria meningitidis infection was found in each age group,with petechia on skin,skin necrosis,immunity correlation fever and complications of nervous system in 87.5%,50.0%,75.0% and 12.5% of the patients,respectively. Conclusions 1.Epidemic cerebrospinal meningitis occurred sporadically in children in Shanghai area,the majority of patients were floating populations.2.Clinical manifestation was typical in patients of serogroup A meningococcal disease.Subdural effusion or ventricalitis was more common in patients of serogroup B meningococcal disease.In serogroup C,Neisseria meningitidis was the most prevalent serotype leading to epidemic cerebrospinal meningitis.More cases were found in patients infected with serogroup C,Neisseria meningitidis with severe shock and immunity correlation fever compared with the other groups.Prophylactic vaccination of serogroup C polyvalent meningococcal organism should be recommended.
4.Relationship between formation of intestinal microflora and food allergy in infants
xiao-hui, WANG ; yi, YANG ; ying, WANG ; xiao-lu, YU
Journal of Applied Clinical Pediatrics 2004;0(09):-
Objective To investigate the hypothesis that food allergy in infants may be associated with variation in their intestinal microflora. The formation of intestinal microflora in healthy infants and changes in food allergic infants were detected.Methods 16S rRNA gene sequences specific for bifidobacterium, lactobacillus and escherichia coli in fecal were quantitatively detected by real-time PCR. The three fecal floras were assessed in 71 healthy infants and 100 infants with food allergy. Results After birth,there were bifidobacteria colonized in infantile intestine,then the number increased rapidly up to 5 times at the sixth month, which was always the preponderant flora. Lactobacilli was also presented in infantile intestine 1 month after birth and augment gradually. The number of Escherichia coli was less than bifidobacteria and lactobacilli and appeared to decline during the early infants. The number of bifidobacteria and lactobacilli in the infants with food allergy were markedly less than that in the healthy infants, but escherichia coli was significantly more than that in the healthy infants.Conclusions During the first year of life,the intestinal microflora in infants is in a developing process. Compared with the healthy infants,bifidobacteria and lactobacilli decrease, but escherichia coli increase in the food allergic infants.These results indicate that the probiotics may be benefit to the prevention and treatment of food allergy.
6.Penile rehabilitation after radical pelvic surgery.
Xiao-lin LU ; Yi-jun SHEN ; Ding-wei YE
National Journal of Andrology 2015;21(5):463-466
Prostate cancer, bladder cancer, and rectal cancer are common malignancies in the male pelvis. The incidence rate of erectile dysfunction (ED) following radical prostatectomy, cystectomy or rectal cancer surgery is about 25% - 100%. The main cause of post-surgery ED is mainly attributed to injury of neurovascular bundles, which may lead to reduced oxygenation in and fibrosis of the penile tissue. Early penile rehabilitation after surgery can improve or restore the erectile function of the patients. This article focuses on penile rehabilitation after radical pelvic surgery.
Cystectomy
;
Erectile Dysfunction
;
etiology
;
rehabilitation
;
Humans
;
Male
;
Pelvic Neoplasms
;
surgery
;
Penile Erection
;
Penis
;
Postoperative Complications
;
rehabilitation
;
Postoperative Period
;
Prostatectomy
;
adverse effects
;
Prostatic Neoplasms
;
surgery
;
Rectal Neoplasms
;
surgery
;
Urinary Bladder Neoplasms
;
surgery
8.Establishment and evaluation of a dynamic in vitro intestinal absorption model of lipid formulations.
Ying LIU ; Tao YI ; Huan DI ; Lu XIAO ; Jikui HE
Acta Pharmaceutica Sinica 2011;46(8):983-9
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.
9.Optimization of novel self-microemulsifying mouth dissolving films by response surface methodology.
Lu XIAO ; Tao YI ; Ying LIU ; Di HUAN ; Jikui HE
Acta Pharmaceutica Sinica 2011;46(5):586-91
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.
10.Influence of silica on intestinal absorption of solid self-microemulsifying drug delivery systems.
Di HUAN ; Tao YI ; Ying LIU ; Lu XIAO ; Jikui HE
Acta Pharmaceutica Sinica 2011;46(4):466-71
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.