Objective To Investigate the preparation method, the release profile and structure of the polyelectrolyte layer- by-layer coated chitosan-alginate microgels. Methods The cores of the microgels were prepared by a high voltage electrostatic system, and the semipermeable membrane outside the microgel was polyelectrolyte deposits on the core surface through electrostatic attraction. The influences of different ratios of materials on the expansion property and the in vitro cumulative release of the coated microgels were evaluated by a single factor experiment. Results The prepared polyelectrolyte-coated microgels were well-shaped, with a narrow range of diameter distribution. The lag time of in vitro release was 2. 67 h; the release was rapid after lagging, with the cumulative in vitro release being 72% within 3 h. Conclusion Polyelectrolyte layer-by- layer coated chitosan-alginate microgels can release payload in a pulsed fashion in vitro.

Objective To Investigate the in vitro and in vivo release of chitosan-alginate microgels coated layer-by-layer by polyelectrolyte self-assembly. Methods The cores of the microgels were made by gelatinization using electrostatic microencapsulated and coated by polyelectrolytes using electrostatic attraction. The effects of different layers and ratios of polymer on the in vitro lease of FITC-dextran were evaluated. Histrological examination was carried out to observe the in vivo release process by injecting the coated microgels into mice. Results The results showed that alginate and calcium chloride concentrations and polyelectrolyte layers markedly affected the lag time of pulsed release and the relasing speed after lagging. Conclusion The release of microgels coated layer-by-layer by polyllectrolyte can be controlled in vitro and can be observed in vivo; meanwhile, the microgels are safe and have good biocompatibility.

Pulsed drug delivery (PDD), which can be released at well-defined time points as the therapy needs, can decrease the frequency and avoid taking drug at night, thus improving patient compliance. Here we introduce three kinds of programmed PDD systems independent of external chemical triggering; they are divided according to the triggering mechanisms, degradation-triggered PDD, osmotic pressure-triggered PDD, and both degradationi and osmotic pressure-triggered PDD. This paper reviews preparing technique, release mechanisms and influencing factors of the three PDD systems. The release profiles of pulsatile PDD can be regulated for different therapeutic needs, requiring no external triggers; especially that the PDD system triggered by both degradation and osmotic pressure has a bright future.

This article is to explore the practical application of concept maps in nursing teaching practice to make it as a learning tool to promote undergraduates to make a meaningful study. Besides, the results is applied in research on improving the teaching method so as to provide an effective teaching policy and evaluation tools to promote the scientific research and clinical practice in nursing care.

In order to provide scientific basics for exploitation and sufficient application of Dendrobium officinale leaves resources, the phenol-sulfuric acid method was applied to determine the polysaccharide content. The monosaccharides were derivated by PMP and the derivatives were identified by HPLC-DAD-ESI-MS(n) and the contents of mannose and glucose were determined simultaneously. Similarity evaluation system for chromatographic fingerprint of traditional Chinese medicine (2004A) was employed to generate the mean chromatogram and similarity analysis of the samples was carried out. The results demonstrated that polysaccharide content, monosaccharide compositions and composition ratio had an obvious difference between stems and leaves. The polysaccharide content of stems was higher than that of leaves. Monosaccharide composition in leaf was significantly different from that in stem. The polysaccharide from stems was composed of mannose and glucose, however the polysaccharide of leaves was acid heteropolysaccharide and was mainly composed of five monosaccharides, including mannose, galacturonic acid, glucose, galactose and arabinose. The similarity value of the 14 batches was above 0.9, indicating that similarity of fingerprints among different samples was high. The study can provide evidence for expanding the medicinal parts of D. officinale.
Chromatography, High Pressure Liquid ; Dendrobium ; chemistry ; Mass Spectrometry ; Plant Extracts ; chemistry ; Plant Leaves ; chemistry ; Plant Stems ; chemistry ; Polysaccharides ; chemistry

Objective To understand the current situation of iodine deficient disorder(IDD) 10 years after achieving the stage goal of eliminating IDD in Longyan city and to evaluate the effect of prevention and treatment measures, and to provide the basis for the development of control strategies. Methods There were 7 counties in the city, and each county(city, district) was as a unit to carry out the inspection for organization and leadership,iodine salt management, monitoring and control, health education (referred to as the four management indicators)according to "The County-Level Assessment and Evaluation Implementation Detailed Rules of Realizing the Goal to Eliminate IDD in Fujian Province". According to the east, west, south, north and middle positions in each county,a village and a primary school were selected. Forty 8 to 10 year-old students in each school were randomly selected to check thyroid and among them 20 students were collected urine samples to determine urinary iodine. Nine townships were selected in the 7 counties of the city and among which 4 administrative villages were selected in each township. Eight edible salt samples from each household in each administrative village were collected to test salt iodine. Goiter was examined by palpation, the level of urinary iodine was examined by arsenic and cerium spectrophotometry, salt iodine was detected by direct titration. Results The average score of the four management indicators was 94.1 in Longyan city. The adjusted goiter rate of children aged 8 - 10 years old was 1.9%. The median of urinary iodine was 278.6 μg/L, among which less than 100 μg/L accounted for 4.57%(32/700), 100 -＜ 200 μg/L accounted for 24.00%(168/700), 200 - ＜ 300 μg/L accounted for 25.29%(177/700), and higher than 300 μg/L accounted for 46.14%(323/700). The using rate of qualified iodized salt was 98.86%. The coverage rate of iodized salt was 99.50%, the qualified rate of iodized salt was 99.35%, and the rate of non-iodized salt was 0.50%. All the indicators had reached the national standard to eliminate IDD. Conclusions After achieving the stage goal of eliminating IDD, the disease is stable and the effect of control measures are significantly. But the iodine provided has a trend of more than suitable. Therefore, it is reasonable to reduce the current salt iodine content.

Objective To understand the current situation of iodine deficiency diserders(IDD) in Longyan City and to evaluate the effect of prevention and control measures of IDD in order to provide evidence for formulating prevention and control tactics. Methods During the year of 2006 and 2007, the 30 primary schools were screened by population proportion survey(PPS) from the 7 counties of Longyan City. Forty children aged 8-10 years in each school were randomly selected as a group to examine thyroid, and 7 children in each group were selected to measure the urine iodine and the salt iodine at the same time. The goiter rote, the median urinary iodine, the consumption rate of qualified iodized salt, the iodine salt coverage rate, the rate of qualified iodized salt and the non-iodized rate were detected. Results The goiter rate of children aged 8-10 years old in Longyan City was 0.94%(79/8438). The median urinary iodine was 259.12 μg/L. The consumption rate of qualified iodized salt was 97.86% (1462/1494). The iodine salt coverage rate was 99.46%(1486/1494). The rate of qualified iodized salt was 98.38 (1462/1486), and the non-iodized rate was 0.54% (8/1494). Conclusions All indicators have reached the national standard of eliminating IDD in Longyan City.

Objective To explore the changes of plasma corticotrophin releasing factor (CRF) levels in the young rats with hypoxic-ischemic brain damage.Methods Two hundred and forty young rats were randomly divided into three groups:hypoxic-ischemic brain damage group ( model group,n =80),sham-operated group ( n =80),and normal control group ( n =80).The plasma CRF levels of rats in three groups were detected at 1 h,3 h,6 h,12 h,l d,3 d,5 d and 18 d after hypoxia-ischemia,per ten rats for each time point.Plasma CRF levels were measured by radioimmunoassay.Results Plasma CRF levels of model group,shamoperated group and normal control group showed no significant difference in the young rats after 1 h,3 h,6 h,12 h of hypoxia-ischemia ( P ＞ 0.05 ).But plasma CRF levels in the model group were respectively significantly lower than those of sham-operated group and normal control group after 1 d and 3 d of hypoxia-ischemia ( P ＜0.001 ),and then recovered to the control group levels after 5 d and 18 d of hypoxia-ischemia ( P ＞0.05 ).Conclusion Hypoxia-ischemia affects plasma CRF levels in the young rats,which is related with the duration after hypoxia-ischemia.

Animals ; Chickens ; physiology ; Eating ; drug effects ; Injections, Intraventricular ; methods ; Neuropeptide Y ; administration & dosage ; pharmacology

Objective To dynamically observe the changes of cytokines of splenocytes in mice immunized with recombinant bifidobacteria bifidum (Bb)- Eg95-EgA31 vaccine of Echinococcus grauulosus (Eg). Methods Balb/c mice were vaccinated by 5× 108 colony forming unit(CFU) orally and 5 × 105 CFU intranasally, respectively.Mice were killed on week 0,2,4,6,8,10, 12,14,16, 18 and 20 after immunization, respectively, and spleens were separated for cell culture with the stimulation of EgAg, concanavalin A (ConA) or lipopolysaccharide (LPS). The splenocyte supernatants were collected to determine the levels of interferonγ(IFN-γ), interleukin(IL)-12, tumor necrosis factor α(TNF-o) and IL-l0 using enzyme linked immunosorbent assay(ELISA) with MRS as control. Results In the oral immunization group, the levels of IFN-γ, IL-12, TNF-α and IL-10 showed a significant increase from week 2 to week 8, week 2 to week 8, week 4 and week 6 to week 10 after vaccination, respectively, and reached the highest level on week 4, week 2, week 4 and week 6 after vaccination, respectively;in EgAg stimulation group, the levels of IFN-γ, IL-12, TNF-α and IL-10 were (700.0 ± 115.5), (45.0 ± 5.8), (350.0 ± 57.7), (112.5 ± 14.4)ng/L, respectively, compared with week 0[(35.0 ± 5.8), (12.5 ± 2.9), (190.0 ± 11.6), (25.0 ± 5.8)ng/L, P ＜0.05 or ＜ 0.01] and MRS control group[(37.5 ± 5.0),(13.8 ± 2.5), (195.0 ± 5.8), (27.5 ± 2.9)ng/L, P＜ 0.05or ＜ 0.01]. In the intranasal immunization group, the levels of IFN-γ, IL-12, TNF-α and IL-10 showed an obvious increase from week 2 to week 8, week 2 to week 8, week 2 to week 6 and week 6 to week 16 after vaccination,respectively, and reached the highest level on week 2, week 2, week 4 and week 8 after vaccination, respectively;in EgAg stimulation group, the levels of IFN-γ, IL-12, TNF-α and IL-10 were (700.0 ± 115.5), (55.0 ± 5.8),(275.0 ± 28.9), (140.0 ± 11.6)ng/L, compared with week 0[(35.0 ± 5.8), (12.5 ± 2.9), (190.0 ± 11.6), (25.0 ±5.8)ng/L, P ＜ 0.05 or ＜ 0.01] and MRS control group[(37.5 ± 5.0), (13.8 ± 2.5), (195.0 ± 5.8), (27.5 ± 2.9)ng/L, P ＜ 0.05 or ＜ 0.01]. The cytokine levels in the groups with EgAg, ConA or LPS stimulus were significantly higher than those in the corresponding splenocytes suspension groups(P ＜ 0.05 or ＜ 0.01) , and the cytokine levels in the groups with ConA or LPS stimulus were obviously higher than those in the corresponding groups with EgAg stimulation(P ＜ 0.05 or ＜ 0.01). Conclusion The mixed Th1 and Th2 type response can be induced in mice immunized with the recombinant Bb-Eg95-EgA31 vaccine of Echinococcus granulosus in the early stage of immunization(2 to 6weeks).