Manganese ; blood ; Spectrophotometry, Atomic ; methods

Objective To observe the alteration of scavenger receptor class A types Ⅰand Ⅱ (SR-AⅠ/Ⅱ) gene knock-out on lipid metabolism in mice fed with high-fat diet, and explore the underlying mechanism. Method The SR-AⅠ/Ⅱgene knock-out and wild-type male mice were fed with normal and high-fat diet for 12 w. Thereafter, the level of lipid metabolism (such as the levels of lipids in blood and liver) was detected with enzyme method or oil red O staining, and the expression of scavenger receptor class B typeⅠ(SR-BⅠ) and CD36 in liver was analyzed by RT-PCR. Results Under high-fat diet condition, as compared with wild-type mice, the levels of TG, TC, LDL and HDL in SR-AⅠ/Ⅱgene knock-out mice were decreased at 3, 6, 12 w (P0.05). Conclusion The alteration of lipid metabolism induced by high-fat diet in SR-AⅠ/Ⅱgene knock-out mice might be relative with the up-regulated SR-BⅠmRNA expression and the counter transport of peripheral lipids to liver.

Myeloid-derived suppressor cells (MDSCs) are a heterogeneous population of immature myeloid cells at different stages of maturation.MDSCs mediate the suppression of the anti-tumor immunity,and play a crucial role in cancer tolerance through suppressing the activity of T cells and natural killer cells,inducing T-regs and involving the angiogenesis,and then contribute to the tumor development and metastasis.Promoting the differentiation of MDSCs,reducing its quantity and inhibiting its function by using various methods may contribute to the recovery of patients normal immune status,the tumor progression control,and improvement of the efficacy of other anti-neoplastic therapies.Therefore,possible novel therapeutic approaches targeted at MDSCs could be considered and developed rapidly now.

0.05). Conclusion:There is bigger difference process of tumor apoptosis between different cell types in the same topography site. Survivin may play adjuvant roles and Bcl-2 may play main roles in the inhibition of cell apoptosis in SCLC while the case is just reversed in NSCLC,it suggests that there were different apoptosis inducing factor and different apoptosis pathway due to different cell type in NSCLC and SCLC.

BACKGROUND: Differentiation of embryonic stem (ES) cells into cardiomyocytes in vitro has been studied in great detail in the world. However, much of what is currently known about cardiomyocyte differentiation from ES cells has been learned from studies on mouse in China, few studies are on human ES cells.OB JECTIVE: To investigate the differentiation effcacy of human ES cells into functional cardiomycytes with the human H14 ES cell line.DESIGN: Suspending method was used to form pseudo-embryo proper of human ES cells so as to observe ratio of pseudo-embryo proper with rhythmic contraction and expression of specific gene of myocardium in various differentiated phases.SETTING: Molecular Biology Laboratory of Stanley Ho Center for Emerging Infectious Diseases, School of Public Health, the Chinese University of Hong Kong.MATERIALS: Human ES cell line H14 was obtained from WiCell Research Institute (Wisconsin, USA) with a license agreement.METHODS: The experiments were carried out in the Molecular Biology Laboratory of Stanley Ho Center for Emerging Infectious Diseases, School of Public Health, the Chinese University of Hong Kong from August to December of 2006.The H14 ES cell colony was used to form embryoid bodies (EBs) by using suspending method. Four days later,pseudo-embryo proper was cultured in gelatin-coating 6-well culture plate (5-10 embryo proper/well) and spontaneously differentiated into moving pseudo-embryo proper. Rhythmic contraction was observed under microscope and RT-PCR was used to detect expression of special genes of myocardium.MAIN OUTCOME MEASURES: Ratio of pseudo-embryo proper with rhythmic contraction and expression of specific gene of myocardium in various differentiated phasesRESULTS: Spontaneously contracting cells appeared as cluster and were identified in approximately 2% of EBs at differentiation day 8 and increased to as many as 10% of the EBs by day 16. The beating rate of contracting cells arranged at 70-100 beats per minute. RT-PCR analyses demonstrated that cells isolated from spontaneous beating areas within the EB expressed the cardiac transcription factors GATA-4 and Nkx2.5, cardiac progenitor gene Isl-1 and cardiomyocyte marker gene α-MHC.CONCLUSION: This is the first time to report human ES cells can effectively differentiate into functional cardiomyocytes in China.

To evaluate the association of ealpain-10 gene UCSNP-43 polyorphism with type 2 diabetes in Chinese Han population.Meta-analysis showed that calpain-10 gene UCSNP-43 polymorphism may be associated with type 2 diabetes in Chinese Han population.Allele G and genotypo GG may be risk factors for type 2 diabetes,while allele A and genotype GA may be the protective factors.

Objective To investigate the proliferation,apoptosis and cell cycle and possible mechanisms of different breast cell lines by difluoromethylorithine (DMFO).Methods The growth of breast cancer MDA-435 (ODC GG) cell lines and SK-br3 (ODC AA) cell lines treated with DFMO were observed.The apoptosis and cell cycle were detected by flow cytometry.PCR was applied to detect the changes of A and G alleles of ODC G316A in MCF-7 cells treated with DFMO.Results The growth inhibition rates of MDA-435 and SK-br3 cells treated with 10 mmol/L and 20 mmol/L DFMO after 48 h were 24.1％ and 33.6 ％,46.3 ％ and 53.5 ％,respectively,and there was statistical significance (t =2.134,P =0.021,t =2.213,P =0.019).The growth inhibition rates of MDA-435 and SK-br3 treated with 10 mmol/L and 20 mmol/L DFMO after 72 h were 28.9 ％ and 35.7 ％,54.3 ％ and 65.4 ％,respectively,and there was statistical significance (t =2.434,P =0.015,t =2.489,P =0.013).The apoptosis rates of MDA-435 (ODC GG) and SK-br3 (ODC AA) cells both dealt with 20 mmol/L of DFMO after 24 h,48 h and 72 h were (7.58± 2.06) ％ and (13.88±3.45) ％ (t =2.047,P =0.041),(43.28±14.28) ％ and (59.96±16.42) ％ (t =3.680,P =0.000),(77.87±30.25) ％ and (93.08±32.15) ％ (t =3.293,P =0.000 1),respectively.The proportions of S stage cells MDA-435 (ODC GG) and SK-br3 (ODC AA) cells under the same condition after 24 h,48 h and 72 h were (13.25±2.38) ％ and (12.89±2.21) ％ (P ＞ 0.05),(21.43±3.12) ％ and (12.24±3.55) ％ (t =2.638,P =0.012),(16.32±3.23) ％ and (15.24±3.01) ％ (P ＞ 0.05),respectively.After the treatment by DFMO,the expression of ODC G316A allele A in breast cancer cell line MCF-7 (ODC AG) was reduced (t =3.708,P =0.000),and the expression of G had no significant changes.Conclusion The proliferation inhibition and apoptosis in breast cancer cells treated by DFMO is different in breast cancer cells with different genetic type of ODC G316A.DFMO can inhibit the activity of ODC,and the mechanism may be that DFMO could selectively bind to ODC G316A allele A.

Objective:To explore the effect of 1,25-dihydroxyvitamin D3 on the mast cell tryptase (MCT) in asthmatic guinea pigs. Methods:A total of 60 male or female healthy guinea pigs were randomly divided into control group (group A), asthmatic group(group B), and 1,25-dihydroxyvitamin D3 group(group C), with 20 cases in each group. To establish asthmatic guinea pig models, 1ml peanut oil was filled into stomach in the morning in group A and group B , and 1ml peanut oil with 1,25-dihydroxyvitamin D3 was filled into stomach in group C. Airway resistance (Re) of asthmatic guinea pigs was detected, and the bronchoalveolar lavage fluid (BALF) cells were counted. Lung tissue with HE and MCT immunohistochemical staining were used to observe the pathological changes in lung tissue and the distribution of MCT. Results:After injection of different concentration of acetylcholine chloride, the Re in group B and group C were increased significantly compared with group A (P<0.05);compared with group B, the Re in group C were decreased significantly (t=-5.385, -5.761, -6.184,-13.574, P<0.05);the total number of BALF cells and eosinophils were increased significantly in group B and C (t=19.618, 9.598, 10.854, 5.388, P<0.05);compared with group B, the total number of BALF cells and eosinophils in group C was decreased significantly (t=-5.555,-5.392, P<0.05);the number of tryptase positive cells in group B was increased significantly than that in group A (t=21.312, P<0.05), and in addition to the alveolar septum and submucosa, the cells were also distributed around blood vessels and outside the cells; the number of tryptase positive cells in group C was decreased significantly compared with group B, and the difference was statistically significant (t=5.043, P<0.05). Conclusions:After the asthmatic guinea pigs are treated with 1,25-dihydroxyvitamin D3, their BALF, Re, infiltration degree of inflammatory cells in the trachea and lung tissue and airway inflammatory reaction are reduced significantly. 1,25-dihydroxyvitamin D3has a certain inhibiting effect on the activation of mast cells and the release of MCT granules.

Objective To investigate the expression and clinical significance of miR-125b in patients before and after treatment of acute myeloid leukemia (AML) with different types.Methods The levels of miR-125b were measured by using real-time fluorescence quantification PCR (qRT-PCR) in 65 AML patients (all AML samples from the Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University,and the control samples isolated from cord blood which were obtained after normal full-term delivery of babies) before and after treatment,and then the relationship between the levels of miR-125b and patients＇ sex,age,peripheral blood cells,type clinically,relapse and therapeutic effect were analyzed.Results Of newly diagnosed AML patients and the control samples,miR-125b positive rate was 100％.The miR-125b expression levels in the control group was 1.50,and its expression in AML was 11.06,and the difference was significant (P =0.036 6).In complete remission (CR) group of acute promyelocytic leukemia (M3),the expression of miR-125b after induction therapy was significantly reduced,and CR rate of miR-125b decreased group was 91.3％,while that of the increased group was 50.0％,and the difference was significant (P =0.042 6).The miR-125 b expression level was decreased from 29.7 ± 4.9 to 19.2 ± 6.0 after chemotherapy,and the difference was significant (P ＜ 0.036 6).In non-M3 AML,CR rate of miR-125 b decreased group was 86.7 ％,while that of the increase group was 42.1％,and the difference was significant (P =0.021 5).There was no correlation between miR-125b expression and patients＇ gender,age and peripheral blood cells.Conclusions The differences in expression of miR-125b is very important in disease occurrence and progress.Using qRT-PCR to dynamically detect the expression of miR-125b dynamically in AML patients before and after therapy may predict outcome more precisely and has the potentials as an effective biomarker in determining prognosis,monitoring the risk of recurrence,and guiding the treatment.

Objective To promote the differentiation of Flk1+CD31-CD34-cells isolated from adult adipose tissues into pancreatic islet endocrine cells in vitro.Methods Flk1+CD31-CD34-cells were first cultured and plated in medium supplemented with B27,epidermal growth factor(EGF),and basic fibroblast growth factor(bFGF).Next,the culture medium was changed.The glucose concentration in the serum-free medium was increased.At the same time,betacellulin and nicotinamide were added.Reverse transcription polymerase chain reaction(RT-PCR) was used to detect the expression of nestin,ngn3,insulin promoter factor-1(IPF-1),insulin,and glucagon before and after differentiation induction;immunofluorescent staining for nestin,insulin and glucagon and radioimmunoassay(RIA) for insulin.Results Initially,a nestin positive precursor cell population was found,then small round cells increased in number after 6 days.Later on,they were differentiated into islet-like clusters.The induced cells resulted in the formation of clusters which exhibited higher insulin secretion and other pancreatic endocrine hormones.RT-PCR detected an enhanced expression of pancreatic genes in the differentiated cells.Immunofluorescence revealed a high percentage of insulin-expressing cells in the clusters.Furthermore,the intra-cellular insulin content was detected by RIA after the induction culture.Conclusion These cells represent a previously unidentified adult intrinsic pancreatic precursor population and are a promising candidate for cell-based therapeutic strategies.