Study on the expression and mutation of human telomeric repeat binding factor （hTRF1） in 10 malignant hematopoietic cell lines

Objective: Detecting the expression and mutation of human telomeric repeat binding factor (hTRF1) in 10 malignant hematopoietic cell line cells on the base of determining its genomic structure and its four pseudogenes to clarify if h TRF1 mutation is one of the factors of the activation oftelomerase. Methods: hTRF1cDNA sequences were obtained from GenBank, its genome structure and pseudogenes were forecasted by BLAST and other biology information programs and then testified by sequencing.Real-time RT-PCR was used to detect the expression ofhTRF1mRNA in 10 cell line cells, including myelogenous leukemia cell lines K562, HL-60, U-937, NB4, THP-1, HEL and Dami; lymphoblastic leukemia cell lines 6T-CEM, Jurkat and Raji. Telomerase activities of cells were detected by using telomeric repeat amplification (TRAP)-ELISA protocol. PCR and sequencing were used to detect mutation of each exon of h TRF1 in 10 cell line cells. Results: h TRF1 gene, mapped to 8q 13, was divided into 10 exons and spans 38.6 kb. Four processed pseudogenes of hTRF1 located on chromosome 13, 18, 21 and X respectively, was named as ψhTRF1-13, ψhTRF1-18, ψhTRF1-21 and ψhTRF1-X respectively. All cell line cells showed positive telomerase activity. The expression of hTRF1 was significantly lower in malignant hematopoietic cell lines cells (0.0338, 0.0108～0.0749) than in normal mononuclear cells (0.0493, 0.0369～0.128) (P=0.004). But no significant mutation was found in all exons of hTRF1 in 10 cell line cells. Four variants were found in part of intron 1,2 and 8 ofhTRF1. Their infection on gene function is unknown and needs further studies. Conclusion: hTRF1 mutation is probably not one of the main factors for telomerase activation in malignant hematopoietic disease.     

A study of the relationship between expression level of TRF1 protein and telomerase activity in human acute leukemia

INTRODUCTION Telomeres are distinctive DNA-protein struc-tures that cap the ends of linear chromosomes.It is very important to keep the chromosomes stabilization.Telomerase activity is closely linked to attainment of cellular immortality,a step in carcinogenesis,while lack of such activity contributes to cellular senes-cence.Telomerase is activated in more than85%ofmalignant tumors(Hiayma et al.,1997).Human te-lomeric repeat binding factor1(TRF1)is a telomere associated with proteins a…     

Study on the serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) in patients withHelicobacter pylori infection

Objective: To evaluate the interaction between serum levels of soluble intercellular adhesion molecule-1 (sICAM-1) andHelicobacter pylori (H. pylori) infection in patients with chronic gastritis and peptic ulcer. Methods: The serum levels of sICAM-1 in 205 patients with chronic gastric diseases were detected by ELISA method and the status ofH. pylori was determined by histologic examination, RUT,¹⁴C-UBT, and serology. The sera obtained from 18 healthy volunteers served as controls. Results: The serum levels of sICAM-1 were significantly higher in patients withH. pylori positive than those of H. pylori negative (889.43±32.52 ng/ml vs. 747.07±30.45 ng/ml,P<0.05). The serum levels of sICAM-1 in patients with mild, moderate and severe infection ofH. pylori were 841.68±72.36 ng/ml, 905.43±37.59 ng/ml and 1012.54±49.34 ng/ml, respectively (P<0.05). The serum levels of sICAM-1, proved to be significantly correlated with the density ofH. pylori colonization in gastric mucosa (r _s=0.316,P<0.001). The serum levels of sICAM-1 in patients with chronic gastritis and peptic ulcer were significantly higher than those in healthy controls (P<0.05). Conclusions: These results indicated thatH. pylori infection up-regulates the expression of sICAM-1.     

Survival of the biocontrol agents Brevibacillus brevis ZJY-1 and Bacillus subtilis ZJY-116 on the spikes of barley in the field

Fusarium head blight (FHB) caused byFusarium graminearum is a devastating disease that results in extensive yield losses to wheat and barley. A green fluorescent protein (GFP) expressing plasmid pRP22-GFP was constructed for monitoring the colonization of two biocontrol agents,Brevibacillus brevis ZJY-116, on the spikes of barley and their effect on suppression of FHB. Survival and colonization of theBrevibacillus brevis ZJY-1 andBacillus subtilis ZJY-116 strains on spikes of barley were observed by tracking the bacterial transformants with GFP expression. Our field study revealed that plasmid pRP22-GFP was stably maintained in the bacterial strains without selective pressure. The retrieved GFP-tagged strains showed that the bacterial population fluctuation accorded with that of the rain events. Furthermore, both biocontrol strains gave significant protection against FHB on spikes of barley in fields. The greater suppression of barley FHB disease was resulted from the treatment of barley spikes with biocontrol agents before inoculation withF. graminearum. Project supported by the National Natural Science Foundation of China (No. 30230250) and Science and Technology Committee of Zhejiang Province (No. 2003C22029), China     

胆管癌中p27Kip1、VEGF的表达、意义及相互关系

目的 :探讨 p2 7Kip1、VEGF在胆管癌中的表达及相互关系。 方法 :采用免疫组化技术检测 32例胆管癌标本中p2 7Kip1及VEGF的表达。结果 :p2 7Kip1、VEGF在胆管癌和正常胆管组织中的阳性表达率分别为 5 6 .2 5 %和 11.1% (P <0 .0 1) ;81.2 5 %和 33.3% (P <0 .0 1)。p2 7Kip1、VEGF在胆管癌中的表达具有相关性 (P <0 .0 5 ) ,与分化程度、转移水平有关 ,与大小、生存期无关。结论 :p2 7Kip1、VEGF在胆管癌中高表达 ,p2 7Kip1、VEGF与胆管癌的发生、发展有关。     

Effects of gas supersaturation on lethality and avoidance responses in juvenile rock carp (Procypris rabaudi Tchang)

Laboratory experiments were conducted to determine the effects of total dissolved gas (TDG) supersaturation on acute lethality and avoidance responses in juvenile rock carp (Procypris rabaudi Tchang). The juvenile rock carp were exposed to water with different levels of supersaturation (105%, 115%, 120%, 125%, 130%, 135%, 140%, and 145%) and depth of 0.20 m at 25°C for 60 h. Median lethal time (LT50) was used to assess the lethal responses corresponding to different levels of gas supersaturation. The results show that half of the juvenile rock carp died at the 120%, 125%, 130%, 135%, 140%, and 145% levels of supersaturation, and the LT50 corresponding to different levels of supersaturation was 18.7, 15.4, 8.2, 6.6, 3.5, and 1.7 h. When the level of supersaturated water is below 115%, the mortality is negligible. Avoidance responses were observed 5 min after the fish were put into equilibrated water (99%, 0.08 m deep) and water with different supersaturated levels (105%, 115%, 125%, 135%, and 145%, 0.08 m deep) at 25 °C. The fish exhibited strong avoidance responses in supersaturated water when the gas supersaturation was above 135%. However, they exhibited an obvious preference to supersaturated water when the gas supersaturation was below 115%. Thus, the juvenile rock carp can likely survive in water with a supersaturated level of 115%.