OBJECTIVE: To conduct the in vitro test on drug release of rifampin encapsulated in a carrier made of porous phosphate glass ceramics and to analyze main factors which affect the drug release rate. METHODS: A certain quantitative of rifampin was sealed in a hollow cylindrical capsule which consisted of chopped calcium phosphate crystal fiber obtained from glass crystallization. The rifampin concentration was measured in the simulated physiological solution in which the capsule soaked. RESULTS: Rifampin could be released in a constant rate from the porous glass ceramic carrier in a long time. The release rate was dependent on the size of crystal fiber and the wall thickness of the capsule. CONCLUSION: This kind of calcium phosphate glass ceramics can be a candidate of the carrier materials used as long term drug therapy after osteotomy surgery.
Mesenchymal stem cells (MSCs) are considered as an ideal treatment for multiple diseases including ocular disease. Recent studies have demonstrated that MSCs-derived exosomes have similar functions with MSCs. Exosomes are nanovesicles surrounded by a phospholipid layer that shuttle active cargo between different cells. They are capable of passing the biological barrier and have potentials to be utilized as natural carrier for the ocular drug delivery.
Objective To summarize recent research advancement on gene therapy for hepatic ischemia-reperfusion injury (IRI). Methods Relevant references about basic and clinical researches of hepatic IRI were collected and reviewed. Results Recent experimental researches indicated that the expression of several genes and cytokines could protect hepatic cells by suppressing cell apoptosis, decreasing the production of oxyradical, remaining and improving portal venous flow, promoting bilifaction, self immunoloregulation and decreasing inflammatory reaction, so that it could decrease IRI. Conclusion IRI could be decreased by regulating the expressing of target genes or transducing relative genes in vivo, but the path of gene transfer and the selection and optimization of gene carrier still need more basic and clinical researches to prove.
Bone morphogenetic protein (BMPs) has been so far regarded as one of the highly potent osteoinductive growth factors. Recombinant human bone morphogenetic proteins have been utilized extensively in the disciplines of orthopedics, stomatology, etc. For clinical application, BMPs are usually loaded in carriers with a controlled-release system, to maintain concentration to induce de novo bone formation at the desired site. In this article, the research advancements of the carriers and release systems of BMP are reviewed.
Objective To prepare chitosan microcarriers and to use it to cultivate rat primary hepatocytes. Methods The crosslinked chitosan microcarrier was prepared by the reaction of glutaraldehyde with chitosan. Various factors that influence the preparation were studied and the reaction conditions were optimized. Rat primary hepatocytes cultured on chitosan microcarrier were observed by using phase contrast microscope and scanning electron microscope. Results Chitosan microcarriers with good properties could be prepared by adjusting the concentration of chitosan solution and the quantity of glutaraldehyde. Rat hepatocytes cultured on chitosan microcarriers retained the spherical shape as they have in vivo. And albumin secretion can last over one week. The highest albumin secretion rate reached 26.7μg/24h/ml. Conclusion Chitosan microcarriers is a promising scaffold for hepatocyte attachment, which can be used in bioartificial liver support system.
Objective To assess the efficacy and safety of Chinese medicinal herbs for asymptomatic hepatitis B virus(HBV) infection. Data Source The trials registers of the Cochrane Hepato-Biliary Group, the Cochrane Library and the Cochrane Complementary Medicine Field were searched in combination with MEDLINE, EMBASE, and handsearches of Chinese journals and conference proceedings. Data Selection Randomized clinical trials with 3 months follow-up comparing Chinese medicinal herbs versus placebo, no intervention, non-specific treatment, or interferon treatment for asymptomatic HBV carriers were included. No language and blinding limitations were applied. Data Extraction Data were extracted independently by two reviewers. The methodological quality of trials was assessed by the Jadad-scale plus allocation concealment. Results Three randomized clinical trials (307 patients) with low methodological quality following patients for three months or more after the end of treatment were included. Herbal compound Jianpi Wenshen recipe showed significant effects on clearance of HBV markers compared to interferon: relative risk 2.40 (95 % CI 1.01 to 5.72) for clearance of serum HBsAg, and 2.54 (1.13 to 5.70) for seroconversion of HBeAg to anti-HBe. Phyllanthus amarus and Astragalus membranaceus showed no significant antiviral effect compared with placebo. Analysis of pooling eight randomized clinical trials with less than three months follow-up did not show a significant benefit of Chinese medicinal herbs on viral markers. No serious adverse event was observed. Conclusions There is insufficient evidence for treatment of asymptomatic HBVcarriers using Chinese medicinal herbs due to the low quality of the trials. Further randomized, double blind, placebo-controlled trials are needed.
Objective To review the progress and clinical application of malleable bone paste/putty. MethodsRecent literature about malleable bone paste/putty was reviewed and analyzed. ResultsThe preparation and clinical application of malleable bone paste/putty have become increasingly mature. Many kinds of malleable bone paste/putty have been applied extensively and the good clinical results have been achieved in the treatment of the irregular bone defects. The materials and methods for preparing malleable bone paste/putty are different. Then they have different bone repair abilities. ConclusionMalleable bone paste/putty provides effective method to treat irregular bone defects. But the malleable bone paste/putty still has some shortage, so further researches should be carried out.
Recently, drug delivery materials have become the hotspot of medical study. Suitable delivery material plays an important role in constructing an excellent drug delivery system. Silk fibroin is a naturally occurring protein polymer with excellent biocompatibility, remarkable mechanical properties, biodegradability and outstanding processability. Due to its unique properties, silk fibroin has become a favorable carrier material for the incorporation and delivery of a range of therapeutic agents. Based on the structure and characteristics of silk fibroin, this article provides an overview of the recent research progress of silk fibroin used as drug delivery materials.
ObjectiveTo observe intervention effect of Shenlingcao oral liquid on asymptomatic chronic hepatitis B virus carriers (AsC). MethodsA self control before-after trial was conducted in the First Affiliated Hospital of Jiangxi University of Traditional Chinese Medicine and the Ninth People's Hospital of Nanchang City from November 2011 to May 2012. A total of 64 AsCs were treated by Shenlingcao oral liquid (1 bottle/d, 200 mL, once daily for 6 months). Serum HBV viral load, six specific serum markers of HBV and 11 liver function index were tested and recorded before and at the 1th, 3th, 6th months of the treatment. Analysis of variance of repeated data was conducted. ResultsAfter one month of the treatment, 35/57 (61.40%) AsCs' serum HBV-DNA loads decreased, 1 log decrease was observed in 15 cases, 2 log decrease was observed in 4 cases, and decrease under the detection limit was observed in 12 cases. 41/57 (71.93%) AsCs' serum HBV-DNA loads decreased after 3 months of treatment, 1 log decrease was observed in 21 cases, 2 log decrease was observed in 5 cases, and decrease under the detection limit was observed in 15 cases. 31/49 (63.26%) AsCs' serum HBV-DNA loads decreased after 6 months of the treatment, 1 log decrease was observed in 19 cases, decrease more than 2 log was observed in 7 cases, and decrease under the detection limit was observed in 12 cases. The serum HBV viral loads at different time points of the treatment were significantly different (P<0.001). As medication time went, AsCs' serum HBV viral loads presented a decrease trend after taking Shenlingcao oral liquid, especially obvious at the 3th month. ConclusionShenlingcao oral liquid could help promote AsCs' ability of clearing virus and controlling serum HBVDNA loads.
Polymeric hydrogels have been widely researched as drug delivery systems, wound dressings and tissue engineering scaffolds due to their unique properties such as good biocompatibility, shaping ability and similar properties to extracellular matrix. However, further development of conventional hydrogels for biomedical applications is still limited by their poor mechanical properties and self-healing properties. Currently, nanocomposite hydrogels with excellent properties and customized functions can be obtained by introducing nanoparticles into their network, and different types of nanoparticles, including carbon-based, polymer-based, inorganic-based and metal-based nanoparticle, are commonly used. Nanocomposite hydrogels incorporated with polymeric micelles can not only enhance the mechanical properties, self-healing properties and chemical properties of hydrogels, but also improve the in vivo stability of micelles. Therefore, micelle-hydrogel nanocomposites have been recently considered as promising biomaterials. In this paper, the structure, properties and methods for preparation of the micelle-hydrogel nanocomposite systems are introduced, and their applications in drug delivery, wound treatment and tissue engineering are reviewed, aiming to provide reference for further development and application of the nanocomposites.