Objective To construct a voxel mouse model combining with Monte Carlo method used for radiation dose calculation.Methods A set of slice images obtained from a nude male mouse (28 g) was utilized, all slice images were registered,some organs or tissues were identified, segmented and filled with specific color, and finally the physical property was defined by MCNP application.Results A mouse model with a voxel size of 0.2 mm×0.2 mm×0.2 mm, consisting of 14 organs or tissues,was constructed, which could satisfy the requirement of precision for radiation dose distribution calculation and moderate computing time.Conclusion The voxel mouse model can be used to calculate the quantity of ionization radiation dosimetry in related areas including radiological medicine, nuclear medicine and space radiation medicine.

Objective To establish a calcification mode in vitro of human vascular smooth muscle cells (HVSMCs) induced by β-GP. Methods Primary HVSMCs were obtained from human embryo by plant method and confirmed by stain with α-sm-actin antibody. The cells after 4-6 passages were divided into two groups.The control group was incubated with normal DMEM medium while the calcification group was incubated with the medium containing 10 mmol/L β-glycerophosphate for 10 days.Calcification was confirmed by alizarin red S stain and alkaline phosphatase(ALP) assays. Results The primary cells observed by S-P stain were positive and the cells after being stained were pale yellow. After being induced with β-GP, the cells of calcification group began concentric growth and formed vesicles. Alizarin red S staining showed that the reaction of calcifying nodules was red,ALP activity was higher than that of controls at various time points(4 d,6 d,8 d and 10 d,P＜0.01 ).Conclusion The HVSMCs could be induced into calcification in vitro by β-GP, and this model contribates to further studies of vascular diseases.

Objective To establish a method of isolation, purification, primary culture and identification of alveolar type Ⅱ epithelial cells(AT-Ⅱ).Methods The AT-Ⅱs were isolated from Wistar rats by trypsin,purified by differential centrifugation, erythrocyte spallation, differential adherence and immune adherence, and identified by observing the morphology of cultured cells under the inverted phase and tannic acid staining. Results and Conclusion The cultured primary AT-Ⅱs in vitro presented single or island form growth, and their shapes were round or elliptical. A great deal of fine particles showed sharp contrast, and were observed in intracytoplasm. The cell nuclei were clear. They were positive for tannic acid staining.The primary culture AT-Ⅱs obtained from improved isolation and purification have good growth state and purity, and are suitable for research in vitro.

Objective To establish a method for culturing neonatal mice cardiomyocytes, and construct an in vitro model of cardiomyocytes for assessing the cardiac toxicity of chemicals. Methods Hearts of neonatal mice of 1 day old were digested with enzyme mixture of trypsin/collagenase type Ⅱ/dispase and the cell suspensions were pre-plated to flask for a short time and then seeded on coated dishes. The cultured cells were treated with 5-fiuorine-deoxy-uridine(15 μg/ml)and uridine(35 μg/ml)to enrich cardiomyocytes that were identified according to the morphology and immunocytochemistry of α-actin antigen. Cardiac myocytes were incubated with 0-64 μg/ml of a fusarium mycotoxin butenolide(BUT) for 12 h. Cell viability was then evaluated by MTT assay. Microscopic observation showed that BUT induced significant morphological changes including cellular swelling, vacuolation and breakage of muscle fibers. Results It was found that 96% of the cultured cells were cardiomyocytes and the myocytes kept beating after 90 days of culture. Concentration-dependent decreases in cell viability following exposure of cardiac myocytes to BUT were observed. Conclusion The results indicated that relatively pure primary culture of neonatal mice cardiomyocytes is successfully established. BUT possesses the potential to induce myocardial toxicity.

Objective To investigate the endurance or resistance of different bacteriophages to bubbling stress in different sampling solutions,to select the optimum sampling solution from three different ones and to select relatively stress-resistant bacteriophages from five different ones.Methods AGI-10(all glass impinger)was used as the representative for all the impingers that would bubble during operation to fulfill the bubbling experiment.Three different sampling solutions used,such as distilled water(DW),phosphatic buffer solution(PBS),and suspension medium(SM),were divided into two groups by adding olive oil(50 μl) or otherwise(0 μl).The impingers were operated 30 min at a flow rate of 7.0 L/min.The titers of bacteriophages and the volume of final sampling solutions were determined before the corrected survival probability was used to evaluate the stress resistance of several different bacteriophages.Results It was found that the survival probability of the same bacteriophage bubbling with different sampling solutions was different except for bacteriophage F2.The use of SM as the collection fluid was related to a high survival probability which remained unchanged between 50 μl and 0 μl olive oil.The corrected survival probability was 79%,77%,86%,50% and 71% for phage SM701,SM702,PhiX174,EcP1 and F2 respectively after 60 minutes of impingement at a flow rate of 7.0 L/min.Conclusion The endurance or resistance of different kinds of bacteriophages in the same sampling solution is different.SM might be an optimum sampling solution for phages.Bacteriophage SM701,SM702 and PhiX174 are more resistant to bubbling stress than EcP1 and F2.

Objective To obtain antibiotic-resistant mutants producing metabolites with antitumor activity from wild-type actinomycete strains without antitumor activity. Methods An actinomycete strain L35-1 was used as an initial strain for obtaining antibiotic-resistant mutants, which is a marine-derived wild-type strain without antitumor activity with an inhibition rate of 2.8% at the 1000 μg/ml of high sample concentration on K562 cells. The antibiotic-resistant mutants both from auto-mutagenesis and chemical mutagen-induced mutagenesis were selected by single colony isolation on antibiotic-containing plates according to the method for obtaining drug-resistant mutants in ribosome engineering. The antitumor activity was assayed by the MTT method using K562 cells for the mutants with aqueous acetone extracts of the whole broth of their fermentation.Results A total of 114 neomycin-resistant (ner) and 68 streptomycin-resistant (str) mutants, all from auto-mutagenesis, was obtained on drug-containing plates. Among them, the 7 ner and 3 str mutants appeared to be bioactive with an inhibition rate above 20% at the 100 μg/ml sample concentration on K562 cells. On the other hand, 41 str and 32 ner mutants from DES-induced mutagenesis and 46 ner mutants from NTG-induced mutagenesis were obtained by mutagen-induced mutation coupled with the single colony isolation on antibiotic-containing plates, among which, one str mutant from DES-induced mutagenesis and one ner mutant from NTG-induced mutagenesis were bioactive with an inhibition rate over 20% at the 100 μg/ml sample concentration on K562 cells. Conclusions The present result has revealed that the wild-type actinomycete strains without bioactivity might become a great source initial strains to obtain bioactive mutants by drug-resistant mutation technique.

Objective To study the inhibitory effect of pterin acid (PTA) against ricin and recombinant ricin A chain protein. Methods Luciferase protein synthesis inhibition assay in a cell-free system and in vitro cytotoxicity experiments were performed to assess the biological activity of ricin and rRTA treated with PTA.Results The result showed that PTA could significantly inhibit the activity of ricin and rRTA in a dose-dependent manner.Conclusion PTA might be used as a small molecular probe to develop an evaluating system for ricin/RTA small molecular inhibitor in vitro. The cell-free system adopted in the current study could also serve as a necessary basis for screening some novel small molecular compounds against ricin and RTA in the future.

Objective To obtain the fusion genes of several human orphan G protein coupled receptors (oGPCRs) with Gi1α subtype of G protein and their expression system. Methods The whole open reading frames of GPR45, GPR85, GPR174 and Gilα were cloned by RT-PCR from HepG2 cDNA separately,and the corresponding fusion genes were amplified by overlap extension PCR. Then, the fusion genes-containing pBacmids were successfully constructed with the Bac-to-Bac baculovirus expression system indicated by specific transposition and virus recombination. The insect Sf9 cells were transfected with pBacmid-oGPCRs-Gi1α, and the supernatant containing recombinant virus was harvested. With the supernatant, insect Sf9 cells were infected under an optimized condition (MOI=5, infection time=72 h) and the fusion proteins were prepared and detected by Western blotting.Results The three fusion genes of GPCR45, GPR85 or GPR174 with Gi1α were obtained. The corresponding fusion proteins could be properly prepared in Sf9 cells.Conclusion Human oGPCRs could be fused with Gilα, and the fusion genes could be expressed using the Bac-to-Bac baculovirus expression system in insect Sf9 cells.

Biotechnology supremacy is a newly-advanced power theory. It is a superior dominance of military biotechnological application based on the microcosm of life structure within a certain period of time. The advancement of biotechnology supremacy and modern biotechnology has created the concept of bio-micro-frontier, which involves information and defense resources of all living ultra-micro-organisms with national and regional characteristics. Being feasible both in theory and practice, the implementation of bio-micro-frontier system is strategically important. This article explores the implementation of bio-micro-frontier in terms of strategy and tactics, which will add a unique dimension to future military transformation and active defense.

The medicine for military use only is an essential material for medical support. The United States of America is one of the earliest countries which has used special medicine to protect the military personnel from injuries and diseases. The current situation of service support in the military of USA is introduced and the challenges facing the development, product, supply and use of the special medicine in USA are analyzed,for reference by our army.