AIM: To investigate the expression of natural killer cell stimulation receptor D(NKG2D) in peripheral blood and the expression of major histocompatibility complex class I chain-related protein A(MICA) on the gastric carcinoma tissue and the neighboring non-cancerous tissue in Tibetan patients with gastric cancer at Qinghai plateau. METHODS: Samples of 33 patients and 20 healthy persons were collected to detect NKG2D in peripheral blood by Flow cytometry analysis. The expressions of MICA in part of the correspondent tissues were examined by RT-PCR and immunohistochemistry.RESULTS: The expression of NKG2D in the plateau of Tibetan patients with gastric cancer group (13.47 ±5.26)% was significantly lower than that in healthy groups (32.62±10.08)%. The mRNA level of MICA in gastric cancer was significantly higher than that in neighboring non-cancerous tissue (P<0.05). The expressions of MICA proteins showed a significant difference between the neighboring non-cancerous tissue (21.21%, 7/33) and the gastric carcinoma tissue (78.79%, 26/33), between the high differentiation (60.00%, 3/5) and the moderate (72.73%, 8/11), low differentiation (88.24%, 15/17). The expressions of MICA were not correlated with tumor size, sex, age, lymph node metastasis of the patients (P>0.05). Spearman rank correlation displayed that the expressions of MICA mRNA were positively correlated with the MICA protein level (r=0.903, P<0.01).CONCLUSION: The immune escape in Tibetan patients with gastric cancer at Qinghai plateau probably relates to the down-regulation of NKG2D and the up-regulation of its ligand MICA. The activity of NK cells and the anti-cancer cellular immunity level are descending in the plateau of Tibetan patients with gastric cancer. The decrease in the receptor NKG2D is a reason for the activity of NK cell descending. 相似文献
The phylogenetic relationships among imported ornamental crayfish belonging to the genus Cherax were inferred from a combined dataset of 3 mitochondrial genes (COI, 16S and 12S) and by comparison with available GenBank sequences of 14 Cherax species. Furthermore, the concordance of previously described species obtained from a wholesaler (Cherax boesemani, C. holthuisi and C. peknyi) with available GenBank sequences was verified based on COI with special respect to comparison with sequences assigned as Cherax species. Recently described species C. gherardiae, C. pulcher and C. subterigneus belong to the northern group of Cherax species. Comparison and analysis with other GenBank COI sequences show previously unreported diversity of New Guinean species, suggesting 5 putative new species. Surprisingly, species assigned to the subgenus Astaconephrops do not form a monophyletic clade; this subgenus should be reappraised relative to the purported typical morphological characteristic of the uncalcified patch on male chelae. Increasing importation of crayfish underscores the importance of accurate species identification. Use of basic molecular methods is a necessary requisite for documenting occurrence, abundance and population trends of target species. Consequently, it helps to support eventual conservation decision‐making by stakeholders. 相似文献
Salinity affects many areas in our country and around the world, resulting in dramatic reductions in plant yields. In this study, the plant yield, some plant quality parameters, and soil salinity in the plant root area were investigated by irrigating tobacco plants (Nicotiana tabacum L.) with different salinity irrigation waters. The experiment was carried out in pots in 4 replicates according to the randomized plot design. Six different salinity of irrigation water applications were applied in the experiment (S0?=?0.38 dS m?1, S1?=?2 dS m?1, S2?=?5 dS m?1, S3?=?8 dS m?1, S4?=?11 dS m?1, S5?=?15 dS m?1). According to the data obtained at the end of the research, as the salinity of irrigation water increased, plant length, leaf width, leaf length, leaf dry weight and leaf number decreased. It was determined that there was a certain increase in nicotine content in the face of the decrease of all examined physical parameters in irrigation water increase. In addition, the salinity values in the plant root zone soils and the salinity values in the outlet (drainage) water have also increased. Salinity threshold value of the tobacco plant was determined to be 2.04 dS m?1. With an increase in salinity by one unit, there was a 7.1% decrease in leaf dry weight. It was determined that the tobacco plant is vulnerable to salinity based on the data collected.