CD72 is a B cell specific receptor that exists in multiple alternative splicing forms. Eight novel alternative splicing forms of CD72 were identified from the spleenocytes of BALB/C mice. Two very unique intron sequences were found in those alternative splicing forms. One kind of splicing variants retained the intron1 in the mRNA. This intron can be translated into 32 amino acid residues without changing the reading frame of the whole proteins. Another kind of splicing variants used an alternative 3' splice site in intron 3(3'AS) which led to premature termination of its encoded protein. The differential expression of the CD72 splicing variants were compared in BALB/C and NZB/W mice that were at different stage of systematic lupus erythematosis(SLE) disease development. It was found that 1) splicing forms containing 3'AS was rare in all samples examinated; 2) splicing forms containing two ITIM domains and transmembrane domains were more abundant in BALB/C mice than in NZB/W mice, even in some cases the two ITIM domains were separated by the intron 1; 3) a shorter splicing form with both exon2 and exon3 missing was expressed highly in terminally diseased NZB/W mice.These results suggested an important role of CD72 alternative splicing forms in B cell receptor signaling and in SLE.

Background:Prognosis of early colorectal carcinoma( ECC)is well because of low rate of lymph-node metastasis ( LNM). How to improve the detection rate and select appropriate therapy for ECC has been an eager task in clinical practice. Aims:To analyze the pathological features of ECC treated by endoscopic resection(ER)or surgery,and evaluate the therapeutic efficacy of ER. Methods:Pathological data of 503 ECC lesions treated by ER or surgery were retrospectively analyzed. Risk factors of infiltration depth,LNM of ECC were analyzed,and therapeutic efficacy of ER was evaluated. Results:The overall detection rate of ECC was 10. 7%. The incidence of LNM was 1. 2%(6/503);the LNM incidence of mucosal high-grade neoplasia was 0%( 0/247 ),while was 2. 3%( 6/256 ) in submucosal carcinoma. The LNM incidence of submucosal superficial carcinoma treated by ER was 0%( 0/31 ). Tumor location, size,histological type and LNM had significant impacts on infiltration depth(P<0. 05). The rates of en bloc,complete and curative resection by ER were 96. 0%,94. 2% and 82. 1%,respectively. Infiltration depth was the risk factor of piecemeal,incomplete and noncurative resection of ER(P<0. 05). Conclusions:The incidence of LNM in ECC is extremely low. Accurate evaluation of character and infiltration depth of lesion before operation is helpful for selecting appropriate therapy. It should be cautious to choose ER for lesions infiltrated into submucosa,thereby to improve the therapeutic efficacy of ER.

Objective To investigate the relationship between Demodex infection and season , sex, different parts and the infectious rate of Demodex in human faces among students of a university and to prevent diseases caused by Demodex infection.Methods The samples of Demodex were collected from sophomores in December 2006 to May 2007.Results The results showed that the infectious rate in male,31.5% in winter and 38.0% in summer respectively, higher than those in female.On the face, the highest infectious rate was on the nose.The infectious rate on the cheeks was lowest.The relationship between Demodex infection and season, sex was observed.Conclusion The infectious rate of Demodex in human faces is associated with the season and sex.

Objective To establish a method of primary culture of human preadipocyte in a serum-free medium. Methods Collangenase digestion was used to dispart preadipocyte.The cells were identified by microscopy stained by oil red O and determination of the activity of Glycerol-3-phosphate dehydronase(G-3-PDH). Results The primary cultured human preadipocyte proliferated in the aserum-free medium successfully.In the differential serum-free medium the cells turned to be round on the 4 th day.The adipose drops began to cumulate in the cells,and to the most quantity until the 21 st day.Conclusion The human preadipocyte can be primarily cultured and induced to differentiate in serum-free medium,which is the base for researching the effects of hormones and factors to the proliferation and differentiation of preadipocyte.

Objective:To study the expressions of vascular endothelial growth factor(VEGF), and thrombospondin (TSP) in oral submucous fibrosis(OSF), and to determine the relationship between VEGF and TSP, so as to investigate their roles in the pathogenesis of OSF. Methods:30 patients with OSF, including early (10 cases), middle (10 cases), late stage (10 cases) were studied. 5 healthy volunteers were chosen as control group. Buccal mucosa biopsies were taken in all samples. Expressions of VEGF and TSP were detected by immunohistochemistry. Results:The expression of VEGF increased in early stage compared with normal oral mucous, and decreased in middle and late stage. The expression of VEGF in early stage had statistical difference compared with control group, middle stage and late stage respectively(P<0.05).The expression of TSP upregulated in early and middle, and downregulated in late stage. There were no statistical significant differences among groups(P>0.05). The expressions of VEGF and TSP had negative correlation(r=-0.620,P<0.05). Conclusions: The abnormal expressions of VEGF and TSP may be a pathogenesis factor of OSF.

Objective To approach the effect of benefiting qi and activating blood circulation therapy on AMI.Methods A total of 120 patients with AMI were recruited into a control group and a treatment group randomly. 60 cases in control group were treated with dextran, nitroglycerin and heparin. While 60 cases in the treatment group were treated with traditional Chinese medicines with the functions of benefiting qi and activating blood circulation on the basis of the control group. Therapeutic effects were observed after two weeks' treatment. Results The effective rat was 95.00% and 81.67% in the treatment group and the control group respectively, showing significant difference(P=0.0341 ＜0.05). In the 3 months follow-up, ischemia happened in the treatment group was significantly lower than the control group (P=0.0284, P＜0.05).Conclusion Combined treatment of TCM and western medicine is better than treatment of western medicine only. Benefiting qi and activating blood circulation therapy is effective on AMI and improves the prognosis.

Objective:To study the effect of interleukin-11(IL-11),ciliary neurotropic factor (CNTF) and transforming growth factor-β (TGF-β) on the hGH gene promoter activity in rat pituitary MtT/S cells and the interaction with pituitary-specific transcription factor Pit-1.Methods:Stable transformed MtT/S cell line which contains hGH gene promoter -484-30 bp and luciferase reporter gene firstly established,then the concentration of GH in the medium and lysate of MtT/S cells and luciferase activities in MtT/S cells were measured after treatment these cells with the above cytokines,the effects of cytokines on secretion and synthesis of GH,and the promoter activity of the hGH gene were observed.Results:The results showed that IL-11(20 nmol/L),CNTF(10 nmol/L) and TGF-β(5 nmol/L) regulated secretion and synthesis of GH,and the luciferase expression in stable transformed MtT/S cells.IL-11 and CNTF had the stimulatory effect,whereas TGF-β had the inhibitory effect.Neither overexpression of Pit-1 nor inhibiting Pit-1 expression affected the regulatory role of these cytokines.Conclusion:IL-11,CNTF and TGF-β regulate the GH production in pituitary MtT/S cell line by regulating the hGH gene promoter activity.Pit-1 may not be involved in these actions.

BACKGROUND:Fetal bovine serum based media used for expanding and cryopreserving human mesenchymal stem cells raise safety concerns in the clinical setting. OBJECTIVE:To investigate the feasibility of human umbilical cord blood plasma as a replacement for fetal bovine serum in culture and cryopreservation of human mesenchymal stem cells derived from umbilical cord. METHODS:Umbilical cord blood units were suitable for this research if they fulfil ed the donor selection criteria of the Guangzhou Cord Blood Bank strictly. Cord blood plasma was ready to use after col ected from the plasma reduction during the suitable cord blood units processing and pooling. Umbilical cord mesenchymal stem cells were harvested from the umbilical cord tissue of health ful-term newborns after delivery by enzyme digestion and were cultured in the presence of Dulbecco’s modified Eagle’s medium/Ham’s nutrient mixture F-12 containing either fetal bovine serum or pooled cord blood plasma. Morphology, proliferation, immunophenotype detected by flow cytometry and differentiation toward adipogenic and osteogenic lineages were utilized for investigating the effect of media on umbilical cord mesenchymal stem cells after 3-5 passages. Then cells were cryopreserved in media containing 10%dimethyl sulfoxide, 20%fetal bovine serum or 20%pooled cord blood plasma for at least 6 months. Viability, adhesion, proliferation, immunophenotype and osteogenic differentiation of the cells were assessed after thawing. RESULTS AND CONCLUSION:The morphology (spindle-shaped and plastic-adherent), phenotype and differentiation potential (osteogenic and adipogenic) were almost indistinguishable between cells cultured in fetal bovine serum or cord blood plasma medium, while cells grown in cord blood plasma medium demonstrated significantly higher proliferation rates than those in medium containing fetal bovine serum. After thawing, the cells maintained their adherence to the culture surface and differentiation potential to osteoblasts, but cells from cord blood plasma cryopreservation medium showed significantly better plastic attachment and produced greater cellnumbers than fetal bovine serum for the first three post-thaw passages. The results demonstrate that cord blood plasma can sever as an effective substitute to fetal bovine serum for growth, maintenance and differentiation of umbilical cord mesenchymal stem cells, and thus it wil be a safe choice for clinical-scale production of human mesenchymal stem cells.

BACKGROUND: Distraction osteogenesis is an effective method for large bone defects, bone tumors and osteomyelitis. However, there is a lack of a standard model in the basic research concerning distraction osteogenesis. OBJECTIVE: To establish a rabbit femoral model of distraction osteogenesis and to assess its osteogenic effect. METHODS: Twenty male New Zealand rabbits were enrolled to establish the rabbit femoral model of distraction osteogenesis using a novel distractor. Subsequently, the gross observation and X-ray examination of the specimens were performed to assess the osteogenic effect. RESULTS AND CONCLUSION: Gross observation: on day 14 after fixation, there were light-colored and dense newborn bones distributing evenly in the distraction gap, and appeared with a columnar connection with the broken ends; the boundary with normal bones became vague. On day 35, the surface of newborn bones in the distraction gap showed the same color and texture with the normal ones, the boundary between the newborn and normal bones was difficult to distinguish, and the bone mineral density was increased notably. Radiology results: on day 14 after fixation, the stent was fixed stably, the broken ends got good reduction, and cloudy shallows connecting the two ends of the normal bones in the distraction gap and increased bone mineral density were detectable. Completely calcified new-born bones, intact bone cortex and open medullary canal were further visible on day 35. These results suggest that the rabbit femoral model of distraction osteogenesis is established successfully using the self-designed single-arm distractor based on rational surgical procedures and standard operations.

Purpose To reconstruct perfusion computerized tomography angiography (PCTA) images from the volume data of low-dose brain CT perfusion scan with iterative reconstruction algorithm, to analyze the capability of PCTA on the display of brain arteries, and to explore the methods to reduce the radiation dose for stroke CT examinations. Materials and Methods This was a prospective study, 55 patients (605 arterial segments) with clinical diagnosis of ischemic cerebrovascular disease underwent cranial CT scan, iterative algorithm low-dose brain CT perfusion scan and conventional cranial CTA examinations using a 256-slice spiral CT. 11 segments of the cerebral artery in each case were analyzed using conventional CTA results as the reference standard to assess the display of brain arteries in PCTA. Results Effective dose of CT perfusion scan was 2.12 mSv. Among the 580 vessel segments which CTA showed no stenosis or stenosis<30%, only one vessel segment of PCTA was inconsistent with CTA; among the 19 vessel segments which CTA showed stenosis≥30%but not occluded, results of 12 vessel segments in PCTA were consistent with CTA, while the stenosis states were exaggerated by PCTA in the other seven vessel segments;results of the two methods were consistent in six vessel segments which was found occluded by CTA. Kw values were >0.75 for the consistency test between PCTA and CTA on the display of brain arteries. Conclusion Radiation dose of iterative algorithm cranial CT perfusion scan is significantly lower, and the images reconstructed from the volume data of perfusion CT are highly consistent with the CTA results, thus are able to meet the needs of the clinical diagnosis.