OBJECTIVE To develop and validate a physiologically based toxicokinetics and toxico?dynamics(PBTK/TD)model for chlorpyrifos(CPF)in rats following both oral and subcutaneous expo?sures to CPF. METHODS ①A PBTK/TD model was established with toxicokinetics and toxicodynam?ics data in literature,which was used for predicting contents of CPF and 3,5,6-trichloro-2-pyridinol (TCP)in blood and activities of acetylcholine esterase(AChE)in the plasma and brain of rats exposed to CPF.②Rats were given 50 mg · kg-1 CPF oral and 50 mg · kg-1 CPF sc simultaneously. Blood and brain samples were collected at 0,1,2,4,6,8,12,24 and 48 h,respectively,after CPF administration (n=5). CPF And TCP contents in plasma,activities of AChE in the plasma and brain were deter?mined,and compared with the simulation values by PBTK/TD model in order to validate the accuracy of the model. RESULTS It was predicted by the PBTK/TD model that after the administration (oral+sc) of CPF 20+20,10+30 and (30+10)mg · kg-1,the concentrations of CPF and TCP in plasma increased and then decreased with time in each group. The inhibitory level of AChE activity in the plasma was orally dose-dependent,while AChE activity of the brain was more sensitive to CPF subcutaneous exposure. The simulation values obtained by the PBTK/TD model were not significantly different from the experimental values obtained by co-administered CPF at(50+50)mg · kg-1. CONCLUSION This CPF PBTK/TD model can quantitatively estimate target tissue dosimetry and AChE inhibition.

This study was aimed to carry the post-marketing revaluation on classical Tibetan medicine of the Seven-ty-flavor Pearl Pill, which will help improve its scientificity, safety and standardization in order to promote its indus- trial development. Literature mining method was used to summarize research information of the Seventy-flavor Pearl Pill, such as the clinical pharmacy sorting. Meanwhile, the successful example of Padma-28 was referred in the analysis of deficiencies in the indications of Seventy-flavor Pearl Pill. The results showed the present situation of clinical combination therapy, pharmacology and toxicology study of Seventy-flavor Pearl Pill. It was concluded that the building of new model of post-marketing revaluation on the Seventy-flavor Pearl Pill can provide re-evaluation scientific basis for Tibetan medicine on its clinical effectiveness and safety.

BACKGROUND:The output of computed tomography (CT) is Digital Imaging and Communications in Medicine (DICOM), whereas the input of three-dimensional (3D) printing is an object Standard Template Library model represented by a triangular mesh. The process of data handing and forrmat conversion are keys to the combination of these two techniques. OBJECTIVE:To explore how to convert CT data into a stereoscopic 3D model efficiently. METHODS:The DICOM in Medicine format data of the patients with femoral fractures were edited and produced by Mimics. We made a 3D model by adjusting the parameters of the 3D printer slicing software, and discussed the significance of 3D model in medical field, especially orthopedics. RESULTS AND CONCLUSION:Mimics software is the bridge to connect two-dimensional CT scan images and 3D images, to create a 3D model by editing the data of DICOM which comes from the CT scanner, with a 3D printing technology. The 3D Model can help doctors for routine clinical diagnosis and treatment, to improve the communication between doctors and patients and the quality of clinical medical teaching. 3D printing also makes medicine more personalized, remote, minimally invasive, and promote the development of medicine to the direction of digital medicine.

Objective To observe the infiuence of recombinant human thyroid stimulating hormone(rhTSH)-aided 131I treatment for patients with differentiated thyroid carcinoma (DTC)and its efficacy on thyroid hormone level.Methods 20 cases with DTC admitted from Nov.2010 to Jun.2014 were divided into 2 groups.11 cases received rhTSH-aided 131I treatment (rhTSH-aided group)and the other 9 cases received 131I treatment after thyroid hormone withdrawal (THs withdrawal group).The influence of the 2 treatment methods on the serum TSH,FT3,FT4,Tg was evaluated,and the therapeutic effects were assessed according to 131I whole body scintigraphy (WBS)and Tg-negative rate.Results The serum TSH was significantly higher in rhTSH-aided group than that before treatment(t=27.70,P＜ 0.001)and in THs withdrawal group (t=7.18,P＜0.001).TSH levels of all patients were＞30 mU/L.WBS displayed that the thyroid remnant clearance rate was 72.73％(8 cases)nd 66.67％(6 cases)respectively in rhTSH-aided group and THs with-drawal group and there was no statistical difference between the 2 groups(x2=0.178,0.673).Conclusion The rhTsH treatment can help to accomplish the preparation of 131I treatment for DTC and acquire satisfactory ablation efficacy.

BACKGROUND:In the treatment of tibial plateau fractures, because of the variety of fracture, the complexity of anatomical changes, X-ray films or three-dimensional CT scan limited by two-dimensional plane, increases the difficulty in preoperative plan and surgical treatment. The application of three-dimensional (3D) printing technology has attracted attention in the department of orthopedics. OBJECTIVE:To explore the auxiliary role of 3D printing technique in preoperative plan and treatment for tibial plateau fractures. METHODS:Thirty patients with tibial plateau comminuted fractures were enroled in this study and divided into two groups: experimental and control groups, with 15 patients in each group. In the experimental group, patients underwent 3D CT scan, which was stored in DICOM format, and processed by Mimics software. Data were converted into STL format, entered 3D printer, and a 1:1 entity size of the fracture model was made, in accordance with repair plan of 3D fracture model. Operation time and intraoperative blood loss were compared between the two groups. At 12 months after treatment, their outcomes were assessed using Rasmussen evaluation criteria. RESULTS AND CONCLUSION: The 3D printing fracture models of 1:1 ratio identified fracture type and made a repair program before surgery in the experimental group. Operation time and intraoperative blood loss were significantly less in the experimental group than in the control group (P < 0.05). After surgery, patients were folowed up for 12 to 18 months. The healing time was 3-5 months, averagely 4.3 months. At 12 months after treatment, the Rasmussen evaluation criteria results showed that the excelent and good rate was significantly higher in the experimental group than in the control group (P < 0.05). These results suggest that the fracture model of 3D can help to make the operation plan. The treatment of tibial plateau fractures is more precise, personalized and visual.

OBJECTIVE Calculate the dietary exposure and exposure risk of Chinese consumers to acephate,using the margin of exposure method.METHODS Determine the bench mark dose of acephate by 21 -day gavage experiment of rats.According to the data from the 2002 National Diet and Nutrition Survey,the 2000 -2006 national food conta mination monitoring program,the 2005 -2006 export monitoring data of customs,calculate the dietary exposure of Chinese consumers to acephate by probabilistic assessment.Estimate the exposure risk by co mparing the margin of exposure with 100. RESULTS The bench mark dose of acephate was 0.75 mg·kg -1 ,the BMDL was 0.51 mg·kg -1 .The exposure of children was higher than that of adults.The proportion at risk of group 1 -6 y,7 -17 y and 18 y or higher was 5%,1 % and 0.1 %,respectively.CONCLUSION So me consumers was of dietary exposure risk to acephate.The high exposure of children should be of great concern.

BACKGROUND:Polyhydroxybutyrate-co-volerate (PHBV) is a noticeable tissue engineering material of polyhydroxyalkanoates family. It has the properties of low immune rejection response and good biocompatibility, and its degradation products are non-toxic.
OBJECTIVE:To investigate the biocompatibility of PHBV membrane material and human bone marrow mesenchymal stem cel s in vitro.
METHODS:Human bone marrow mesenchymal stem cel s at passage 3 were seeded upon PHBV membrane as experimental group and upon conventional culture plates as control group. Then we calculated the adherent cel number of two groups at 1, 2 and 4 hours and got the cel adherent rate. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide assay was used at days 2, 4, 6, 8 to observe the cel proliferation of two groups. Fluorimetric method with the fluorescent dye Hoechst 33258 was used to detect the DNA content of cel s at days 3, 6, 9 and 12 in both groups. After cel s were seeded upon PHBV membrane for 5 days, the cel growth upon the material was examined under a scanning electron microscope.
RESULTS AND CONCLUSION:When the cel s were cultured for 1 hour, the adherent rate in the experimental group was lower than that in the control group;but there were no significant differences between two groups at the other two periods. No difference was found in the cel proliferation and the DNA content between the two groups. Human bone marrow mesenchymal stem cel s seeded upon PHBV membrane for 5 days grew wel with spindle morphology and the intercel ular connections were tight and more extracel ular matrices were observed by scanning electron microscopy. Taken together, PHBV membrane material shows a good biocompatibility with human bone marrow mesenchymal stem cel s.

Objective To study the epidemiology of mycoplasma pneumonia (MP) infection in children and its relationship to meteorological conditions in Guilin. Methods Total of 1 342 hospitalized children with respiratory tract infections from Janu-ary 2011 to December 2012 were recruited, and the serum levels of mycoplasma pneumoniae antibody Ig (MP-Ig) were measured. Meanwhile, monthly meteorological conditions were collected. The relationships between the MP-Ig detection rates and meteoro-logical conditions were analyzed by multiple linear regression analysis. Results The total detection rate of MP-Ig was 23.2%with positive rates as 5.51%, 28.99%, 37.31%and 44.97%for 0-1, 1-3, 3-6 and>6 year-old groups respectively (P<0.01). The positive rate of female was higher than that of male with signiifcant difference (30.08%vs 19.05%, P<0.01). The positive rate of spring, summer, autumn and winter were 18.89%, 17.39%, 23.83%and 33.05%individually (P<0.01). Negative correlation was found be-tween detection rate of MP-Ig and monthly mean air temperature (P=0.001). Conclusion MP is one of the commonest pathogens of respiratory tract infection in children and mostly seen in elder female children with a higher incidence in winter. The main me-teorological factor is the low temperature that affects MP prevalence.

BACKGROUND:As a noticeable tissue engineering material of polyhy droxyalka noates family, poly (3-hydroxybutyrate-co-4-hydroxybutyrate)(P3HB4HB) exhibitsgood biocompatibility, adhesion and mechanicalproperties, presenting aextensive application future in tissue-engineered research.
OBJECTIVE:To investigate the biocompat ibilityin vitroand ectopic osteogenic differentiationin vivoof P3HB4HB and human bone marrow mesenchymal stem cels.
METHODS:Passage 5human bone marrow mesenchymal stem cels transplanted ontothe three-dimensional P3HB4HB scaffoldwereincubated with osteogenic induction medium (test group)or with no osteogenic induction(control group), respectively. After 5-day incubation, thecelgrowth was assessed by acridine orange staining and scanning electron microscopy; after14-day incubation, both kinds of cel-scaffold composites were subcutaneously implanted into the nude mice. At 16 weeks after implantation, the cel-scaffold composites were removed to observeectopic osteogenic differentiationin vivousing hematoxylin-eosin staining, von Kossa staining and colagen type I immunohistochemical staining.
RESULTS AND CONCLUSION:Acridine orange staining showed that cels adhered wel on the surface of the scaffold;under thescanning electron microscope, induced celsgrew wel on the P3HB4HB scaffold and produced abundant extracelular matrixes. In addition, at 16 weeks after implantation, there were osteoidtissues in the test group, positive for von Kossa staining as wel as colagen type I immunohistochemical staining;furthermore, hematoxylin-eosin staining showednumerous osteoblasts and bone lacunas. In contrast, no bone tissues appeared in the control group. To conclude, P3HB4HB is a suitable material for bone tissue engineering.

BACKGROUND:Autologous tissue-engineered bone marrow mesenchymal stem cel s (BMSCs) transplantation is one of the most common methods of treating early osteonecrosis of femoral head, but now there is stil no any special-purpose grafter available in the market. Such surgical transplantation is a laborious, time-consuming and tedious process, which goes against its clinical promotion. OBJECTIVE:To develop a supporting, efficient, special-purpose grafter, to solve the difficulty in stem cel s transplantation during core decompression of femoral head. METHODS:CAD software was used to perform solid modeling for this special-purpose grafter and print them by three-dimensional (3D) fast printing technology. The performance of this special-purpose grafter was tested by femoral head core decompression combined with BMSCs transplantation. It was compared with traditional surgical instrument in terms of duration of operation, intraoperative blood loss, visual analogue scale (VAS) of stem cel/biological fiber col agen complex omission amount and doctor’s satisfaction score. RESULTS AND CONCLUSION:(1) A kind of special-purpose grafter was developed by 3D printing technology rapidly. (2) Compared with the control group, duration of operation, intraoperative blood loss, VAS scores and doctor’s satisfaction scores were significantly improved in the trial group (P<0.05). (3) CAD software combined with 3D printing technology is a highly efficient means for front-line clinicians to perform independent development. The research and development of this special-purpose grafter provides a perfect solution to the laborious, time-consuming and tedious process of cel/biological col agen fiber transplantation.