Objective To investigate the loss of heterozygosity (LOH) of 3p D3S1300 and D3S1289 loci of plasma DNA of lung cancer (LC) patients and evaluate its value for a tumor marker of lung cancer.Methods Two microsatellite markers,D3S1300 and D3S1289,were analyzed by PCR and silver staining to investigate LOH of the plasma DNA and cancer tissue DNA from 69 cases of primary lung cancer,and the plasma DNA from 40 control subjects.Results The percentages of D3S1300 LOH detected in the tumor tissue and plasma DNA of LC patients were 40.6% and 29.0% respectively,while the percentages of D3S1289 LOH were 31.9% and 24.6% respectively.In contrast,only 2 cases of D3S1300 LOH and 3 cases of D3S1289 LOH were found in plasma DNA of control group (P

[Objective]To develop an ideal method for extracting type I collagen from cortical bone and to prepare a collagen-gelatin scaffold.[Method]The cortical bone was disintegrated into bone matrix powder in a high speed mill and was subsequently dehydrated in alcohol,decalcificated in hydrochloric acid and defatted in chloroform:methanol(1:1,v/v).The osscins were extracted using improved pepsin digestion method after the bone matrix powder was dissolved,centrifuged,dialyzed and lyophilized.Type I collagen was then characterized by SDS-PAGE and amino-acid composition analysis.The biomaterial was made of type I collagen and gelatin using freeze-drying method,and the alignment regularities of microscopic channels and their course directions were observed under the scanning electronic microscope.The size of the micropores and the factor of porosity were also measured.[Result] The collagen extracted was confirmed to be type I collagen by SDS-PAGE and amino-acid composition analysis.All the scaffolds looked like circular cylinder,the microscopic channels were arranged in parallel manners,and the pore sizes of the channels were uniform.[Conclusion]Ossein extracted from cortical bone is a real type I collagen that can be applied in the construction of collagen products.

Objective To investigate the difference between anagenetic fibula with normal fibula in mechanical parameters, osteogenesis and tissue morphology,through establishing the model of fibula defect in rabbit.Methods Twenty New Zealand white rabbits were randomly divided.Model group were cuted the right fibula bone with 1.5 cm length.X-ray was used to observe the anagenetic fibula(half month,one month,two months).Stumped the anagenetic and normal fibula(1.5 cm)after two months. Three-point bending test was used to test the mechanical properties;alkaline phosphatase staining was checked the bone-formation ability;HE staining to check the tissue morphology.Results After half month a few new bone were formed at the edges of resec-tion area,one month later new bone were growed in the donor site,and after two month new fibula were completely formed.The three point bending test of fibula showed:there was no statistically significant difference between anagenetic fibula and normal fibu-la(P >0.05);alkaline phosphatase staining and HE staining showed the anagenetic fibula bone forming ability,histology had no sig-nificant difference compared with normal fibula.Conclusion Fibula were regenerated successfully after removing which retaining the periosteum.Compared with the normal fibula,there were no remarkable differences in mechanical parameters,osteogenesis and tissue morphology.

Objective: To detect circulating tumor cells (CTCs) in patients with gastric cancer and evaluate the relationship among CTCs, clinico-pathological characteristics, and prognosis of gastric cancer. Methods: Peripheral blood samples (10 mL in EDTA) were obtained from 45 patients with gastric cancer. CTCs were detected using density-gradient centrifugation and immunofluo-rescence staining. The clinical significance of the two methods were also compared and investigated. Results:CTC-positive case was defined by the presence of at least one CK19 (+)-CTC per 10 mL of the sample. CTCs were found in 27 of the 45 patients with gastric cancer. The presence of CTCs was significantly correlated with lymph node metastasis, distant metastasis, and recurrence (P=0.007, 0.035, 0.035, respectively). However, CTCs were not significantly correlated with sex, age, tumor location, TNM staging, and tumor differentiation (P>0.05). Conclusion:CTCs were associated with poor prognosis of gastric cancer.

Objective To explore the expression and significance of CD44 gastric cancer stem cell biomarker positive circulating tumor cells (CTC ) in peripheral blood of patients with gastric cancer . Methods From March 2010 to December 2012 ,45 patients with gastric cancer and 20 healthy individuals were enrolled .Peripheral blood samples of all the subjects were collected .The expression of CTC and CD44 postive CTC were detected by density gradient centrifugation method and double immunofluorescent staining .Chi‐square test and t‐test were performed for statistical analysis .Results CTC in peripheral blood of healthy controls were not detected .Among 45 patients with gastric cancer ,CTC were detected in 27 patients and 19 of them were CD44‐positive .The difference in positive rate of CTC expression was statistically significant between two groups (χ2 =10 .986 , P<0 .05) .Among 27 CTC‐positive patients , 19 were proximal gastric cancer and 16 of them were CD44‐positive;16 patients had lymph node metastasis and 14 of them were CD44‐positive;13 patients had distant metastasis and 12 of them were CD44‐positive;14 patients had recurrence and 13 of them were CD44‐positive .The CD44 positive CTC was correlated with tumor location ,lymph node metastasis ,distant metastasis and recurrence (χ2=5 .891 ,5 .527 ,5 .787 and 7 .052 ,respectively ,all P<0 .05) .Furthermore ,in 13 patients with recurrence and CD44 positive CTC ,the recurrence time was (10 .54 ± 5 .55) months which was shorter than that of one patients with CD44 negative CTC (19 months) ,and the difference was statistically significant (t= -3 .654 , P=0 .004) .Conclusions CTC which express cancer stem cell marker may be associated with recurrence and metastasis of gastric cancer .It has more important clinical significance to detect this subtype of CTC .

It is for estimating the laboratory statistics from the view of clinical medicine objectively,completely and appropriately that we establish ＜ Laboratory Sciences and Clinical Medicine ＞ which fits the requirement for the modern medical laboratory specialists. In this selective course, we use problem-based learning ( PBL ) teaching method which is different from the traditional one, stimulating students to participate in the study actively and passionately,training them to think in a scientific way and to analyse and solve the problem in a rational way. As a result, it works well which makes us believe it is worth popularizing.

BACKGROUND:The mechanism of steroid-induced avascular necrosis of the femoral head is stil unclear, Cx43 protein as the main gap junction in bone tissue, through transmitting information between osteoblasts, regulates bone cel growth and differentiation, compensatory bone increase or decrease. The relationship between Cx43 protein and steroid-induced avascular necrosis of the femoral head is stil rarely reported.
OBJECTIVE:To explore the changes in Cx43 expression in rabbit models of steroid-induced vascular necrosis of the femoral head.
METHODS:Forty New Zealand rabbits were equal y and randomly divided into model group and control group. Rabbits in the model group were used to establish models of steroid-induced avascular necrosis of the femoral head using endotoxin and hormone. Rabbits in the control group were injected with the same volume of physiological saline at the same time points.
RESULTS AND CONCLUSION:At 4 weeks after model establishment, hematoxylin-eosin staining results revealed that in the model group, the trabecula became thin and distributed disorderly in the femoral subchondral area. Empty lacuna increased significantly. Adipocytes increased. Hematopoietic cel s in medul ary cavity apparently diminished. In the control group, trabecula arranged orderly and empty lacuna could be seen. Bone marrow cel s were abundant, but adipocytes were less. Immunohistochemical method demonstrated that Cx43 protein expression was observed in osteoblasts of the edge of trabecula, cytoplasm of osteoblasts of trabecula, and bone marrow stromal cel s. Western blot assay results showed that alkaline phosphatase and Cx43 protein expression was lower in the model group than in the control group (P<0.05). Results indicated that Cx43 protein expression decreased in the model rabbits, which may be the key link of the occurrence and development of steroid-induced avascular necrosis of the femoral head.

Objective To detect serum IgG4 and IgE levels in children with allergic asthma and rhinallergosis to provide an im-portant laboratory evidence for its diagnosis ,treatment and prevention.Methods The serum IgG4 and IgE levels were detected in 118 children patients with allergic asthma ,167 children patients with rhinallergosis and 150 healthy children(control group) under-going physical examination in the same period.Results The levels of serum IgG4 and IgE in the allergic asthma group and rhinal-lergosis group were significantly higher than those in the control group ,the difference was statistically significant (P<0.05).In the intra-group comparison of the allergic asthma group and rhinallergosis group ,the positive rate of serum IgG4 was higher than that of serum IgE ,the difference was statistically significant (P<0.05).The positive rate of joint detection of serum IgG4 and IgE in these two groups was higher than that of single index detection ,the difference was statistically significant (P<0.05).The positive rate of serum IgG4 in the allergic asthma group was lower than that in the rhinallergosis group ,the difference was statistically sig-nificant(P<0.05).The positive rate of serum IgE in the allergic asthma group was lower than that in the rhinallergosis group ,but the difference was not statistically significant (P>0.05).Conclusion Serum IgG4 and IgE have a certain clinical significance in the occurrence ,treatment and surveillance of allergic asthma and rhinallergosis in children.

Objective To investigate functional connectivity changes in Parkinson disease in the resting brain using functional magnetic resonance imaging.Methods Nine patients with Parkinson disease and eight age-matched healthy volunteers were entered into the study.The bilateral globus pallidus were chosen as seed points, the functional MR data acquired in the resting state were processed to investigate functional connectivity in PD patients and the results were compared with those of the controls.Results In age-matched healthy controls, there are regions which had functional connectivity with bilateral globus pallidus, including bilateral temporal poles, bilateral hippocampus, bilateral thalami, posterior cingulate cortex, right middle occipital gyrus and fight superior parietal gyms.In PD patients, brain regions including bilateral cerebellum, left hippocampus, bilateral superior temporal gyri, left inferior frontal gyms, left middle frontal gyms, left precentral gyms, left inferior parietal gyrus and left superior parietal gyms, had functional connectivity with bilateral globus pallidus. Compared to healthy controls, increased functional connectivity in bilateral cerebellum, bilateral temporal lobes, left frontal lobe and left parietal lobe, and decreased functional connectivity in bilateral thalami were observed in PD patients.Conclusion Abnormal changes of brain functional connectivity exists in Parkinson's disease in the resting state.

Objective To construct double expression retroviral vectors targeting chronic myeloid leukemia (CML) b3a2-type mRNA and investigate its effect on the phenotype of K562 cells. Methods The eGFP coding sequence was inserted into the retroviral vector pMSCV-neo to construct pMSCV/GFP, then H1-RNA pol III-based transcription cassettes was subcloned into it to form pMSCV/GFP-H1-BCR/ABL40AS. Two control vectors pMSCV/GFP-H1-BCR/ABL40S & pMSCV/GFP-H1-BCR/ABL80AS were constructed in addition. All these constructions were identified by restriction enzyme analysis and DNA sequencing. After that, the recombinant vectors were transferred into retrovirus packaging cell line PT67 by using lipofectamine2000, and G418 were used to select stable virus-producing cell lines. Viral titer was determined by infection of NIH3T3 cells sequentially. The cell-growth curve was assayed, cell apoptosis was checked with Annexin V-PE/7AAD double staining and flow cytometry analysis after 24-hour infection, the PKR phosphorylation was assayed by Western blotting. Results The plasmids were successfully constructed. Four cell lines, named as PT67-MSCV/GFP, PT67-40as, PT67-40s and PT67-80as were gained by G418 selection, and virus titers were 6.2?10~ 5 , 5.6?10~ 5 , 4.6?10~ 5 and 6.0?10~ 5 CFU/ml respectively. PT67-40as suspensions could induce K562 cell apoptosis by (22.54?3.19)%, significantly different from PT67-MSCV/GFP or PT67-40s (P