Analysis and measurement of blood physiological and biochemical parameters in Tibetan chickens bred in Guangzhou / 中国比较医学杂志

Objective To investigate and analyze the characteristics of blood physiological and biochemical parameters of Tibetan chickens bred in Guangzhou. Methods Blood samples of Tibetan chickens bred in Guangzhou were collected,and the physiological and biochemical parameters were measured. Results (1)The blood RBC,PLT,PDW, RDW-SD and P-LCR were not significantly different in the males than females(P > 0.05).(2)HCT(P < 0.05), MCHC(P< 0.05),MPV(P< 0.05),HGB(P< 0.01),MCV(P< 0.01)and MCH(P< 0.01)were significantly higher between the males and females.(3)RDW-CV was significantly lower in the blood physiological parameters of males than females.(4)AST,TRIG,ALKP,ALT,Ca,CHOL,CREA,GLU,PHOS and TBIL were not remarkably different in the blood of males than females(P > 0.05).(5)The blood AMYL(P < 0.05)and TP(P < 0.01)were significantly higher in the males than females.(6)The blood ALB(P< 0.01),UREA(P< 0.05), and GLOB(P<0.01)were significantly lower in the males than females. Conclusions The essential data of blood physiological and biochemical indexes of Tibetan chickens bred in Guangzhou are obtained.

Study on immunogenicity and arthritogenicity of a synthetic cyclic citrullina-ted peptide / 中国免疫学杂志

Objective:To establish a synthetic cyclic citrullinated peptide induced arthritis model in mice, explore immunogenicity and arthritogenicity of this peptide. Methods: 36 DBA/1 mice were randomly divided into three groups, which were injected the type Ⅱ collagen ( CⅡ, CIA ) emulsion, cyclic citrullinated vimentin peptide ( CCit-Vim, CCV-IA ) emulsion, cyclic citrullinated vimentin peptide conjugated KLH ( CCit-Vim+KLH,CCV+K-IA) emulsion on day 0 and 21,respectively. Using arthritis index( AI) ,paw swelling to evaluate the incidence of arthritis;ELISA tested serum anti-CCit-Vim antibody,anti-CⅡantibody,anti-CCP antibody and TNF-α, IIF detected AKA;Histopathology of the ankle joint was obsearved. Results: There were three mice appeared arthritis in CCV+K-IA,the incidence rate of 25%,but arthritis occurs later time,short duration,and the incidence and extent of arthritis were lower than the CIA. CCV-IA no arthritis performance. CCV+K-IA produce anti-CCit-Vim antibody were significantly higher than those in CIA (1. 32±0. 59 vs 0. 78±0. 27,P=0. 031). While Anti-CCP antibody of CCV+K-IA were significantly lower than CIA (54. 73±7. 33 vs 64. 37±9. 91,P=0. 007). The anti-CⅡ antibody in CCV+K-IA and CCV-IA were lower than the CIA(15. 73±2. 10, 16. 71±3. 03 vs 19. 50±2. 36,P<0. 05). The TNF-α produced by CCV+K-IA and CIA were both significantly higher than the CCV-IA (645. 61±35. 26,618. 98±53. 32 vs 533. 63±79. 49,P<0. 05). The AKA positive rate of CCV+K-IA is 50% (6/12),significantly higher than CCV-IA 25% ( 3/12 ) and CIA 16. 67% ( 2/12 ) . Histopathology of the ankle showed that the CCV-IA and CCV+K-IA have a mild synovial hyperplasia,no obvious synovial pannus formation and inflammatory cell infiltration. Conclusion:The cyclic citrul-linated peptide conjugated KLH not only has stronger immunogenicity but also has arthritogenicity. It induced a higher positive rate of AKA than CⅡ.

Effect of electroacupuncture on the rat model of type 2 diabetes mellitus combined with renal hypertension / 中国实验动物学报

Objective To observe the therapeutic effect of acupuncture therapy for the rat model of type 2 diabetes mellitus (T2DM) combined with renal hypertension and try to explore its mechanism. Methods We randomly select 10 Wistar rats as the blank group and 40 rats were used to make the model groups, which were divided into simple diabetes group, simple renal hypertension group, the compound group with electroacupuncture and the compound group without elec?troacupuncture, with 10 rats in each group. After a high fat and sugar diet for 4 weeks, the Wistar rats were given strepto?zotocin i. p. injection to establish models of type 2 diabetes mellitus. Renal hypertension was developed by the“2K1C” im?proved method to make unilateral renal artery ligation?induced renal artery stenosis. Then, electroacupuncture treatment was performed on the rats for 2 weeks except the compound group without electroacupuncture. The changes of values of BP, FBG, Cr, BUN, glycated hemoglobin, renin and Ang II were recorded and analyzed. Results The values of BP, FBG, Cr, BUN, glycated hemoglobin, renin and Ang II in the compound group with electroacupuncture showed a significant re?duction compared with the compound group without electroacupuncture after 2 weeks (P0?05). Conclusions The blood glucose and blood pressure in the rat model of compound group can be reduced to a normal level with continuous electroacupuncture at bilateral acupoints Zusanli, and it can also be kept at a stable level after single electroacupuncture for 2-3 days. The acupuncture therapy is more suitable for early clinical treatment and can be used in basic research with advantages of economic, safe, no side effect and so on.

Analysis of hepatitis B virus-related indexes in the urine of HBV transgenic mice / 中国比较医学杂志

Objective To detect and analyze the HBV?related indexes in the urine of HBV transgenic mice and further understand the biological characteristics of transgenic mice, and to clarify the tissue sources of HBV?related indexes. Methods HBV?related indexes in the urine of transgenic mice were tested using enzyme?linked immune sorbent assay ( ELISA ) and fluorescence quantitative PCR ( real?time RCR ) . The tissue sources were confirmed by several experiments, i. e. hydrodynamic transfection of mice, RNA interference to inhibit HBV?expression in the transgenic mice, and to infect normal mice with HBV?positive serum from patients. Results Expression of HBsAg, HBeAg and HBV?DNA was present in the urine of transgenic mice, of which the HBsAg expression level was high (6674 ± 619?8 IU/mL), but lower than that in the serum (16470 ± 2704 IU/mL). The level of HBsAg expression in the urine of male mice was higher than that in female mice. The level of HBeAg expression in the urine was lower and the HBeAg positive rate of urine was higher than that of blood, and the levels of HBeAg expression showed significant inter?individual and inter?sexual differences. HBV?DNA level reached 103 -105 copy/mL in the urine, but no related antibody expression was detected. The experiments such as hydrodynamic infection test indicated that the HBV?related indexes in the urine are derived from replication in the kidneys rather than secreted from the liver, entered into the blood circulation, and discharged from the urine. The kidneys are an independent expression site of HBV. Conclusions The expression of HBV?related indexes is present in the urine of transgenic mice and it is a long?term expression along with the age in months, of which the expression levels of HBsAg and HBV?DNA are rather high and stable. HBsAg titer in the urine of the male mice is higher than that of female mice. HBeAg expression level in the male mice is more stable compared with that in female mice. No expressions of various kinds of antibodies have been found in the urine. The kidneys are an independent expression site of HBV.

Preparation of a rat model of neonatal hypoxic-ischemic encephalopathy / 中国比较医学杂志

Objective To simulate the process of hypoxic?ischemic brain injury at high altitude in a simulated cabin with plateau low pressure environment, and to prepare a rat model of cerebral injuries at different high altitudes. Method Thirty?two 0?day?old neonatal SD rats were divided into four groups, namely group A ( control group) and three test groups:group B (2000 m group), group C (4000 m group), and group D (6000 m group). The rats of control group were reared in a barrier environment. The rats of test groups were placed in a simulated cabin with plateau low pressure environment, and to prepare neonatal cerebral ischemia?hypoxia model by sport activities. The sport movements were carried out in the cabin in a swimming groove 60 min/d, and not less than 20 hours a day at high altitude low pressure environment. Zea Longa 5 point scale standard was used to determine the behavioral scores at the 3 th 7 th 11 th 15 th days, and samples were collected on the 15th day to observe red blood cell morphology using HE and 2, 3, 5?triphenyltetrazolium chloride ( TTC ) staining and ultrastructure by scanning electron microscopy. Result ( 1 ) The neurological scores of the test groups A, B, C were significantly different from that of the control group (P<0?05), and the scores of test group D and control group were very significantly different ( P <0?01 ) . ( 2 ) The histopathological examination using HE staining showed inflammatory cell infiltration in all rats of the test groups, and the extent of inflammatory cell infiltration was positively correlated with the increase of altitude. ( 3 ) The histopathology with TTC staining revealed prominent ischemia in the cerebral cortex of rats in the plateau hypoxic environment. ( 4 ) Scanning electron microscopy showed that the rat erythrocytes were cap?like in the group B, irregular in the group C, and zigzag shape in the group D. Conclusions In this study, a rat model of neonatal hypoxic?ischemic encephalopathy ( HIE) is successfully established by hypoxic cabin combined with sport activity. This model is stable, reliable, more closely mimicking the pathogenesis and clinical manifestation of neonatal HIE than models prepared with other methods, therefore, may be used in related research.

Comparison of human and animal oral microbiota by Illumina sequencing of 16S rRNA tags / 中国比较医学杂志

Objective To provide original reference data for oral ecosystem research, Tibet minipigs, beagle dogs, rhesus monkey, New Zealand white rabbits and Wistar rats were selected to study their respective characteristics of oral microbial mmunities and compared with normal data of humans.Methods Total DNA was extracted from the specimens of oral microbial communities of Tibet minipigs, beagle dogs, rhesus monkey, New Zealand white rabbits and Wistar rats, and used to amplify 16S rRNA V4 fragments with labeled universal primers.The diversity and structure of microbial communities from those animals were compared with that of humans using BIPES and QIIME analysis after Illumina sequencing of 16S rRNA V4 fragments.Results The richness of the oral microbial communities of humans and the five species of laboratory animals was significantly different (P <0.05).Different species of animals have their own unique oral flora, among which the oral flora of the monkey is the most similar to that of humans.Conclusions Among the five species of laboratory animals, the oral microbial communities of rhesus monkeys and humans have highest similarity. Specifically, the Fusobacterium and Porphyromonas levels of rhesus monkeys is most similar to those of humans.Our findings indicate that rhesus monkeys may be suitable animal model for studies of human oral microbial communities.Tibet minipigs may be suitable animal model for Proteobacteria studies, while beagle dogs may be appropriate for modeling of diseases related to Spirochaetes.

Single nucleotide polymorphism analysis of growth hormone gene in Tibet minipigs / 中国比较医学杂志

Objective To screen genotypes of small body in Tibet minipigs by single nucleotide polymorphism analysis (SNP) of growth hormone (GH) gene.Methods The PCR products are sequenced.According to the results, SNP analysis are applied in GH gene 5′fragment of 108 Tibet minipigs .Results Five mutation points were found by comparison.The polymorphism information content of the T45C locus is highest.The results of growth traits of different genotypes showed that the abdomen of 6~8 month old Tibet minipigs of TC genotype at T 45C mutation site is small; the weight and height of 3~5 month old Tibet minipigs of AA genotype at G 84A mutation site is small; the body length and height of 6~8month old Tibet minipigs of GG genotype at G 93A mutation site is small.Conclusion The AA TC, GG genotypes of T45C, G84A, G93A mutation sites in GH gene may be associated with small body .We also found that genetic mutations always occur in the above sites with high heterozygosity and genetic diversity , which can provide rich material for breeding research .

Cloning and sequence analysis of Tibet mini-pig’ s MSTN gene / 中国比较医学杂志

Objective To amplify the encoding full-length sequence of Tibet mini-pigs myostatin ( MSTN) gene and analysis the sequence by bioinformatics software.Method The RNA of liver tissues from Tibet mini-pig was extracted, and reversely transcribed into cDNA.The gene coding region sequence of myostatin gene was amplified through RT-PCR, and then the purified product of PCR was ligated with a pMD19-T and transferred into the bacterium DH5αfor replication.The positive clones were screened and sequenced. The sequence characters were analyzed by using bioinformatics method and phylogeny evolution tree was constructed with other twelve species.Results The coding redion of MSTN gene was 1128bp, and coded 375 amino acids.The amino acid homology analysis showed that the homology rate of amino acid sequence was 99%.Conclusions Molecular phylogeny evolution indicated that it had a close relation with human, dog, banna minipig, sheep, goat, cattle, horse, chimpanzee, rat, mouse except chick and zebrafish, and the most closely related with banna minipig.

A new type occluder applied in atrial spetal defect of mini-pigs / 中国比较医学杂志

Objective To evaluate the efficacy, safety and compatibility of a new type of atrial septal defect ( ASD) occluder in atrial spetal defect mini-pigs model.Methods Five Tibet mini-pigs were selected as the ASD models which were established by the combination of atrial septal puncture and balloon dilation.Then the new type occluder was implanted for the therapy of ASD.Transthoracic echocardiography with color Doppler was used in all animals during closure and in follow up examinations.The animals were killed at 3 months after occlusion for electron microscopical observation and microscopic examination.Result The ASD models had been created in five piglets successfully without complication, all of whom were implanted successfully with the new device without shunts.Postmortem and microscopic examination of the 5 specimens 3 months after placement showed complete.Conclusion Transcatheter ASD occlusion with new type ASD occluder is safe,feasible and effective.This occlusion can repair the atrial septal defect successfully.

An efficient method which can be used to transfect Tibetan minipig embryonic fibroblasts / 中国比较医学杂志

Objective To transfect EGFP gene to porcine embryonic fibroblasts ( PEFs) of Tibetan miniature pigs by Lonza Nucleofector II machine and compare the tansfection efficiency between this method and the lipofection method. Method A plasmid carrying green fluorescent protein ( GFP) was transfected into PEFs of Tibetan miniature pigs via the Lonza Nucleofector II machine ( program U020) and by Lipofectamine 2000.Results 5 hours after nucleofection, green fluorescence was observed, indicating 80%transfecting efficiency in the nucleofection group, which is significantly higher than the lipofection group. Conclusion Nucleofector II machine can efficiently transfect PEFs, provides a reliable method for efficiently generate transgenic Tibetan minipigs.

Safety and histocompatibility of a novel biogradable stent implanted into the coronary artery in a porcine model / 中国组织工程研究

BACKGROUND:In order to solve the problems of poly-l-lactic acid (PLLA) stents, such as poor support, acidic metabolites, we researched a novel biogradable stent-PLLA/amorphous calcium plosphate (ACP). OBJECTIVE: To discuss the safety and histocompatibility of the novel biogradable stent-PLLA/ACP stent implanted in the coronary artery in a porcine model. METHODS:Sixteen novel biogradable stents were randomly implanted into the coronary arteries, left anterior descending branch, left circumflex artery or right coronary artery of sixteen healthy Tibet miniature pigs. The blood routine and blood biochemistry were measured pre-operation and at 1 month after operation. The coronary blood vessels where the stent was implanted were examined by hematoxylin-eosin staining at 1 and 6 months after operation. RESULTS AND CONCLUSION: Compared with pre-operation, the post-operation indicators of the blood routine and blood biochemistry were of no significant difference. Coronary angiography revealed coronary artery patency and no thrombosis, the vascular stent segments exhibited clear boundaries with the surrounding tissue, with no tissue adhesion, necrosis, and adherence abnormalities. The results of hematoxylin-eosin staining showed that there was no significant difference in vascular injury integral between 1 month after operation and 6 months after operation. However, 6 months after operation, the scores of the inflammation were lower (P < 0.05), and the scores of the endothelialization were increased (P < 0.05). There was no myocardial infarction and inflammatory cellinfiltration around the stent. These results suggest that the novel biodegradable stent has good safety and histocompatibility.

Effects of immunization with recombinant fusion protein of extracellular near-transmembrane domain of Tibet minipig leptin receptor on fat deposition in SD rats / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the effect of immunization with prokaryotically expressed recombinant fusion protein of extracellular near-transmembrane domain of Tibet minipig leptin receptor (OBR) on fat deposition in SD rats.</p><p><b>METHODS</b>A pair of specific primers containing BamHI and HindIII restriction enzyme sites was designed to amplify the extracellular near-transmembrane domain (1705-2364 bp) of Tibet minipig OBR gene. After digestion, the amplified fragment was inserted into the plasmid pRSETA between BamHI and HindIII sites. The recombinant plasmid was transformed and expressed in E.coli BL21(DE3) and the product was analyzed by SDS-PAGE and Western blotting. SD rats were immunized with the fusion protein, and the changes in body weight, feed intake, body length, Lee's index, percentage of abdominal fat, liver fat deposition and subcutaneous fat deposition were assessed.</p><p><b>RESULTS</b>The recombinant fusion protein obtained (about 27.6 kD) was expressed in E.coli induced by IPTG and identified by SDS-PAGE and Western blotting. The rats immunized with the fusion protein showed no significant changes in body weight, body length, Lee's index, percentage of abdominal fat or liver fat deposition as compared with the control rats. Nevertheless, the immunization caused significantly increased feed intake and significantly decreased volume of subcutaneous fat cells.</p><p><b>CONCLUSION</b>Immunization with the fusion protein of extracellular near-transmembrane domain of Tibet minipig OBR can promote feed intake and suppress subcutaneous fat deposition in SD rats.</p>

Effect of different radiation doses on intestinal mitochondria in Tibet minipigs / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the injuries of intestinal mitochondria induced by different doses of whole-body radiation in Tibet minipigs.</p><p><b>METHODS</b>Eighteen Tibet minipigs were randomized into 5 radiation groups (n=3) and a control group (n=3). The minipigs in the radiation groups were subject to a total body X-ray radiation at 2, 5, 8, 11, or 14 Gy, and 72 h after the exposure, the mRNA expressions of the intestinal mitochondrial genes were examined using RT-PCR. The changes in the respiratory chain complexes I-IV and the respiratory functions of succinate and NADH were assayed, and the intestinal ultrastructures were observed using transmission electron microscopy (TEM) following the exposures.</p><p><b>RESULTS</b>Compared with those in the control group, the expression levels of the related mitochondrial genes, the activities of the respiratory chain complexes and the function of the respiratory chain were significantly lowered in the radiation groups. At the doses below 8 Gy, the exposures caused significant reduction in the measurements as the radiation doses increased, but at higher doses, these measurements showed no further reductions. Ultrastructurally, exposures at 2 and 5 Gy caused mitochondrial expansion and mild reduction of the density, whereas radiation at 8 Gy or greater resulted in vacuolar changes and obvious expansion of the mitochondria with damages of the mitochondrial cristae and membranes.</p><p><b>CONCLUSION</b>Below the doses of 8 Gy, intestinal mitochondrial damages in the minipigs increase with the radiation dose, but at higher doses, the damages do not further increase with the radiation dose.</p>

Efficiency of three adeno-associated viruses for transfecting enhanced green fluorescent protein in Tibet minipig fetal fibroblasts / 南方医科大学学报

<p><b>OBJECTIVE</b>To compare the efficiency of three different serotypes of adeno-associated virus (AAV) in mediating the transfection of enhanced green fluorescent protein (EGFP) in Tibet minipig fetal fibroblasts (PFFs).</p><p><b>METHODS</b>Three recombinant AAV of different serotypes encoding EGFP were constructed and transfected into primary cultured PFFs at the multiplicity of infection (MOI) ranging from 10(3) to 10(5). The expression rates of EGFP in the PFFs were assessed 72 h after the infection by flow cytometry, and the transfected PFFs were observed under inverted fluorescence microscope. The toxicity of AAVs to PFFs was analyzed using MTT assay.</p><p><b>RESULTS</b>The transfection efficiency of AAV2-EGFP increased with MOI. At the MOI of 10(3), the transfection efficiency of AAV2-EGFP was (33.68∓1.18)%, which increased to (50.80∓2.59)% at the MOI of 10(4) but without obvious further increase at the MOI of 10(5). The other two serotypes of the virus (AAV8 and AAV9) showed no obvious changes in the infection efficiency at any MOIs. The transfection efficiency of AAV8 was (8.3∓0.02)% and that of AAV9 was (2.20∓1.02)% at the MOI of 10(5). Transfection with the 3 viruses caused no adverse effects on the normal cell growth of the PFFs.</p><p><b>CONCLUSIONS</b>AAV2 has a significantly higher infection rate in cultured PFFs than AAV8 and AAV9, and the latter two have a rather low infection efficiency. All the three AAVs have no cell toxicity to the PFFs.</p>

Pathological changes of monocrotaline-induced pulmonary hypertension in miniature pigs / 南方医科大学学报

<p><b>OBJECTIVE</b>To observe the pathological changes in the myocardial and pulmonary tissues in miniature pigs with chronic pulmonary hypertension induced by monocrotaline (MCT).</p><p><b>METHODS</b>Twelve male miniature pigs (weigh 15.0-18.0 kg, aged 4.0-4.5 months) were examined for baseline mean pulmonary artery pressure (mPAP), followed by intraperitoneal injection of 10.0 mg/kg MCT in 10 randomly selected pigs. The mean pulmonary artery pressure at 4 and 8 weeks were determined, and the pathological changes in the myocardial and pulmonary tissues were observed.</p><p><b>RESULTS</b>The baseline mPAP of normal miniature pigs was 15.19∓0.70 mmHg. At 4 and 8 weeks after MCT injection, the sPAP and dPAP were 19.69∓2.47 mmHg and 25.62∓4.88 mmHg, respectively, and the mPAP increased significantly compared with that of the normal control group (P<0.01). Obvious pathological changes such as pulmonary hypertension and right ventricular hypertrophy were found in the pigs 4 weeks after MCT injection, and at 8 weeks, significant pathological changes occurred including right ventricular fibrosis and thickening of the tunica media of the pulmonary artery.</p><p><b>CONCLUSION</b>MCT can cause pulmonary hypertension in miniature pigs 8 weeks after drug administration, shown as increased pulmonary artery pressure and pulmonary vascular remodeling.</p>

Comparison of the Cyt b Gene Sequences in Tibet Mini-Pig and Other Chinese Pigs / 中国实验动物学报

Objective To analyze the Cyt b gene sequences in Tibet mini-pigs and clarify the differences and genetic relationship with other Chinese pigs.Method The sequence of Cyt b gene was amplified from genome DNA of Tibet mini-pig,Bama miniature pigs,Guizhou xiang pigs and Wuzhishan (WZS) pigs.After sequencing,the base sequences were compared and analysed.The blood relationship tree and evolution position of Tibet mini-pig were established.Result There were 14 mutation sites between domestic pigs in China and pigs from Europe.Besides there was a significant differenee in two nucleotide site:a T→C switch in site 420 and the G→A switch in site 883 at the same time.Conclusion Chinese pigs include Bama miniature pigs,Guizhou xiang pigs and WZS pigs,have a very close blood relationship with some of Tibet mini-pigs.It has been confirmed that there is a certain genetic differentiation in the Tibet mini-pig.

Induced differentiation of bone marrow mesenchymal stem cells by gene transfection of growth/differentiation factor-5 / 中华创伤骨科杂志

Objective To investigate the effects of gene transfection with human growth/differentiation factor 5(GDF5)on the growth and difierentiation of bone nlarrow stromal stem cells (BMSCs).Methods GDF5 gene was trans fected into BMSCs by liposome method. Then cell proliferation and cycles were examined by MTT and flow cytometry respectively. Cell morphology was observed under light microscope and electron microscope (EM).GDF5 and Collagen Ⅱ were detected at the level of mRNA and protein by RT-PCR and immunocytochemistry. Alkaline phosphate activity was examined by lead citrate method. Osteocalcin mRNA expression was determined bv RT-PCR. ResulIs GDF5 gene was transfected into BMSCs successfully and the transfected cells still maintained their natural growth and proliferation features. Stable expression of GDF5 gene in BMSCs was obtained. The trans fected ceils had basically the same proliferation ability and cell cycles as the untransfccted ones. After transfection comparatively more polygonal cells could be seen in light microscope, showing irregular arrangement mode. Plenty organells were observed and cell nucleus showed irregular shape under EM. The expressions of Collagen Ⅱ mRNA and protein were positive. But osteocalcin mRNA expression was negative. Conclusion Since BMSCs can be induced by GDF5 to differentiate into chondrogenic cells. GDF5 gene-modified BMSCs may be used as candidate seed cells of cartilage tissue engineering.

Establishment and biological characteristics of mouse models mimicking postoperative human carcinoma metastasis / 南方医科大学学报

<p><b>OBJECTIVE</b>To establish mouse models that mimic the postoperative carcinoma metastasis in human, and observe the difference in the biological characteristics between the models for different human carcinomas.</p><p><b>METHODS</b>GBC, HCT-116, NCI-H460 and SMMC-7721 cells were inoculated subcutaneously in nude mice, respectively, and when the diameter of the resulting tumors reached 1.5 cm, tumor-reductive surgery (TRS) was performed, and the survival and tumor metastasis in the mice were observed.</p><p><b>RESULTS</b>Tumor metastasis in the lungs occurred in 6 nude mice (75%) in GBC group at 10 weeks postoperatively, while no tumor metastasis was found in the control group at 8 weeks, and the survival time of post-TRS mice was 2 weeks longer than that in mice without TRS. In HCT-116 group, the number of nude mice with metastasis in the lungs, spleen, and lymph nodes was 15 (100%), 5 (33.3%), and 15 (100%) 17 weeks after TRS, respectively, while only 3 (23.1%) mice in the control group developed lung metastasis at 9 weeks, and the survival time of the mice showed a 8-week prolongation after TRS. In NCI-H460 group, lung metastasis occurred in 5 nude mice (100%) 14 weeks after TRS, while no metastasis was found in the control group at 10 weeks, and TRS resulted in a 4-week prolongation of the survival time of the mice. In SMMC-7721 group, no metastasis occurred in IRS or control group in spite of the presence of organ failure, and the survival time of the mice was prolonged by 6 weeks after TRS.</p><p><b>CONCLUSIONS</b>Resection of subcutaneously implanted tumor allows greater chances for postoperative metastasis but prolongs the survival of the tumor-bearing nude mice. The likeliness of postoperative metastasis is related to the biological characteristics of the original tumor implanted.</p>

Enterprisingly Exploiting,Vigorously Innovating,and Energetically Developing Comparative Medicine Education——Consideration of the developing direction of laboratory animal subject in the medical college / 中华医学教育探索杂志

Comparative medicine is a new crossing frontier branch subject based on laboratory animal science,and the content,aim and request of its research have been remarkably different from that of laboratory animal science.Acting as the methods,means and support conditions of advancment and development of medicine research,comparative medicine is an important platform ensuring the sustainable development of medicine,and is imperative for the medico to be educated with systemic comparative medicine.

Cloning of integral mature peptide gene of human GDF-5 / 华中科技大学学报（医学）（英德文版）

The integral mature peptide gene of human growth differentiation factor-5 (GDF-5) was cloned to provide the essential foundation for study on the biological characteristics of GDF-5 at gene and protein levels. Two primers were chemosynthesized according to the hGDF-5 sequence reported in Genbank. The hGDF-5 gene was gained by RT-PCR methods from the total RNA extracted from human fetus cartilage tissue, and was cloned into vector pMD18-T. The sequence of recombinant plasmid pMD18-T-hGDF-5 was analyzed by sequence analysis. DNA agarose gel electrophoresis showed that the product of RT-PCR was about 380bp, and double enzyme digestion of the recombinant plasmid corresponded with it. The result of sequence assay was in agreement with the reported hGDF-5 sequence in Genbank. Our results showed that the integral mature peptide gene of human GDF-5 was cloned successfully from human fetal cartilage tissue, and totally identified with the sequence of human GDF-5 in Genbank.