BACKGROUND:Chitosan modification for magnetic iron oxide nanoparticles can improve the agglomeration and stability of magnetic iron oxide nanoparticles, and in addition, it can be used for tumor hyperthermia and gene therapy in the future.
OBJECTIVE:To explore the biocompatibility of magnetic chitosan microspheres which have the potential application in tumor hyperthermia and gene therapy.
METHODS:Magnetic iron oxide nanoparticles were prepared using the modified chemical precipitation. Phacoemulsification method was used to add chitosan into magnetic iron oxide nanoparticles in the preparation of magnetic chitosan microspheres. Then, the fol owing tests were performed. (1) Cytotoxicity test:L-929 cells were cultured in 1640 medium, polyacrylamide monomer solution, 100%, 75%, 50%, 25%of magnetic chitosan microsphere extracts. (2) Hemolysis test:Magnetic chitosan microspheres leaching solution, saline and distil ed water were added. (3) Micronucleus test:Kunming mice were intraperitoneal y injected with magnetic chitosan microspheres suspension containing 5, 3.75, 2.5, 1.25 g/kg iron oxide magnetic fluid, cyclophosphamide and saline, respectively.
RESULTS AND CONCLUSION:Magnetic chitosan microspheres of 200-300 nm in diameter had an increased dispersion effect. The result of 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that the toxicity of the material on L-929 celllines belonged to no cytotoxicity. In the hemolysis test, the hemolysis rate of magnetic chitosan microspheres was 0.69%far less than 5%. In the micronucleus test, magnetic chitosan microspheres suspension did not cause DNA fragmentation and aneuploidy, and did not result in genetic toxicological effects produced by micronuclei. The magnetic chitosan microspheres did not appear with cacogenesis and mutagenesis. From the results, magnetic chitosan microspheres are a kind of high biocompatibility material.

Over the past years efforts have been made by the government to improve the management of clinical laboratories.The government activities such as networking of quality assurance, development and implementation of clinical laboratory standards, and establishment of external quality control mechanisms have facilitated the improvement of clinical laboratory quality.Further definition and integration of clinical laboratory services, introduction of clinical laboratory pathologists and consultation and establishment of a permission mechanism are needed for improving the effectiveness of clinical laboratory services.Government regulations will continue to play an essential role in the clinical improvement process.

Objective:To understand the current situation about pre-registered medical practitioner's ineligible practice from a legal point of view and provides references forthe Law of Medical Practitioners.Methods:The sur-vey is based on cluster sampling method which centralized the selected large clinical teaching hospitals which have launched the standardized residents training.The research is focused in Beijing and involves three kinds of people in-cluding the pre-registered medical practitioners, clinical teaching teachers and health administrators.The descriptive statistics and the Comparison rates between groups by chi-square test rates were adopted.Meanwhile, the 764 medi-cal malpractice cases from the past three years were analyzed in the Courts of the People of Haidian and the Beijing Chaoyang Districts.Results:The clinical trainees“pre-registration” made illegal situations such as independent vis-its, finding a single worker on duty, independent patient disposal, invasive technology's independent operation, inde-pendently writing the medical records, and the absence of tutors on the supervision sites.All of these mischiefs en-hanced the occurrence of medical disputes.Suggestions: Based on the current situation, it is necessary to establish the legal qualifications for the“pre-registered” trainees engaged in the accredited clinical work legislation, physician qualification examination, and in so many angles.Proposing solutions based on legal issues about “the practitioner guidance” should also be efficient.

ObjectiveTo summarize the intraoperative nursing of patients undergoing aparoscopic adjustable gastric banding placation to reduce weight and improve the efficiency of operative cooperation.Method The clinical data on the intraoperative nursing of 9 patients undergoing laparoscopic adjustable gastric banding placation were retrospectively reviewed and analyzed.Result All patients lived through the successful operations and the postoperative rehabilitation were in good condition without postoperative complications and sequelae.Conclusion Full preoperative operation,familiarity with the operative procedures,close cooperation with surgeons are key to smooth performance of the operation and assurance of patient’s safety.

Herbalogical study shows that Xiakucao used in ancient times came from Prunella vulgaris and P. asiotica. The Portion used for medical purpose in ancient times was its stem and leaf, collected during the period of blooming. The portion used today was the spike, collected approach withering. Modern analytical determination showed that the aerial parts of three Prunella specics can also be used as medicine when collected in june and july.

Objective To observe the effect of inhaled nitric oxide(INO) on the nitric oxide synthase (NOS) in piglet suffered from severe meconium aspiration syndrome(MAS). Methods Severe MAS model of piglet was reproduced, the oxygenation effect and the activity of pulmonary NOS were measured, hybridization in situ of pulmonary slices was used to show the gene expression of inducible NOS(iNOS). Results INO therapy attenuated respiratory dysfunction in MAS, while discontinuation of INO induced “rebound pulmonary hypertension”. The activity of iNOS in MAS group is higher than that in control group (16.9?3.1) fmol/(mg Pro?min)vs (11.6?2.7) fmol/(mg Pro?min),( P

ObjectiveTo evaluate the diagnostic and therapeutic methods for hilar cholangiocarcinoma(HCC). Methods In 20 HCC patients serum CA19 9, CA242, CEA were determined preoperatively. A total of 57 HCC patients underwent surgery. Postoperatively 89% (51/57) patients were followed up. Results The sensitivity and specificity of CA19 9 for preoperative diagnosis were 78% and 90%, respectively. 47%(27/57) patients underwent radical resection with 1, 3 year survival rates of 96% and 32%. ConclusionThe results showed that CA19 9 is helpful for the diagnosis of hilar cholangiocarcinoma. Radical resection is effective for prolonging the long term survival in patients with HCC.

Objective To research on a whole blood control material for lymphocyte subset counting by flow cytometry(FCM).Methods To detect lymphocyte subset in whole blood with different preservers by flow cytometric multi-color analysis.Results whole blood control material for lymphocyte subset counting by FCM was prepared.In 2-8℃ refrigerator, the light scatter and CD45 of leukocytes of whole blood control were stable in 72 days. The cluster of lymphocyte, monocyte, neutrophil in plot were separated easily from debris. The lymphocyte subset of whole blood control can be counted by FSC/SSC or CD45/SSC gating. The variation of lymphocyte subset count was less in different preserving day. The coefficient of variation (CV) of lymphocyte subset count was less than 6.5% in our laboratory and less than 13% in external quality assessment among 56 laboratories in China.Conclusion The whole blood control prepared by us can be used for internal quality control and external quality assessment in lymphocyte subset counting by FCM, it is very important signification to ensure the quality and accuracy of lymphocyte subset count.

Objective To determine activity concentrations of natural and artificial radionuclides in the surface soils in Huhhot city,measure environmental radiation level,and evaluate risks to residents health.Methods Radionuclides in 48 surface soil samples were determined by means of the high purity germanium γ spectrometer;environmental radiation level was measured using an environment γ dose rate meter;comparison was made of average activity concentrations in soils between domestically and globally;and the radiation dose to the local residents was estimated by using the methods recommended by UNSCEAR and reported in the related literatures.Results The average values for specific activity of 238U,232Th,226 Ra,40K and137 Cs in the surface soil samples in Huhhot city were (29.29 ± 12.95),(39.33±4.34),(29.77 ±3.21),(650.49 ±62.21) and (1.62 ± 1.53) Bq/kg,respectively;the measured air absorbed dose rate was (86.32 ± 11.92) nGy/h;the annual effective dose to local residents from outdoor γ radiation was 79.27 μSv/year.Conclusions The specific activities of radionulcides in soils and the environmental radiation in surface soil in Huhhot city were at a normal background level,with low risks to health of the local residents.

BACKGROUND:The hepatic stellate cells(HSCs)plays a key role in the development of liver fibrosis.Studies have shown that bone marrow-derived mesenchymal stem cell(BMSCs)transplantation can be used to treat liver fibrosis,but the mechanism for reversal of liver fibrosis remains unknown.OBJECTIVE:To explore the mechanism of bone marrow mesenchymal stem cells to regulate the proliferation of HSCs under co-culture in vitro.METHODS:Rat BMSCs and HSCs in the experimental group were cultured in the plastic culture plate(6 holes)to establish the upper and lower double-cell co-culture system.Rat normal fibroblast cell lines were seeded as control group;HSCs were cultured alone as blank group.Cell proliferation was determined by WST8 and cell cycle was determined by flow cytometry.The Cyclin D1 and P27 mRNA expression in HSC was determined by reverse transcription-polymerase chain reaction(RT-PCR)and the level of Cyclin D1 and P27 protein by Western blot.RESULTS AND CONCLUSION:HSCs co-cultured with BMSCs significantly inhibited HSC proliferation compared with the blank and control groups at 24,48,and 72 hours(P ＜ 0.01);Flow cytometry showed that the percentage of G_0/G_1 phase cells of co-culture group was increased but the S phase cells reduced(P ＜ 0.01)compared with the other groups at 72 hours,and BMSCs blocked HSC to convert from G_0/G_1 period to S phase.After HSCs co-cultured with BMSCs for 24 hours,the expression of Cyclin D1 mRNA and protein was reduced,and significantly less than the blank and control groups at 72 hours(P ＜ 0.01);no differences were detected in P27 mRNA expression in each group during the co-culture(P ＞ 0.05).After co-culture of 24 hours,the p27 protein expression was significantly increased compared with the blank and control groups(P ＜ 0.01).BMSCs inhibited the proliferation of HSCs,possibly through inhibiting CydinDI expression,increasing the p27 protein expression to cause cell cyde arresting in G_0/G_1 phase.