ABSTRACT
Objective To investigate the correlation between NRAMP1 gene polymorphisms and susceptibility to tuberculosis ( TB) in Tibetan people in Qinghai. Methods A case-control study was con-ducted in this study, involving 99 Tibetan patients with TB and 89 healthy Tibetans. The single nucleotide polymorphisms of NRAMP1 gene at rs17235409 and rs3731865 sites were detected by using TaqMan probe method. Gene cloning and sequencing typing were performed to analyze the single nucleotide polymorphisms of NRAMP1 gene at the rs17235416 site. SPASS20. 0 software was used to statistically analyze the correla-tion between NRAMP1 gene polymorphisms and susceptibility to TB in Tibetan people. Results No signifi-cant difference in the genotype frequencies of rs3731865 and rs17235409 was found between the two groups (χ2=0. 852, P=0. 356;χ2=0. 279, P=0. 597). The genotype frequencies of TGTG/TGTG and TGTG/del+del/del at the rs17235416 site were 70. 7% ( 70/99 ) and 29. 3% ( 29/99 ) in patients with TB and 86. 5% (77/89) and 13. 5% (12/89) in healthy subjects. There were significant differences in the geno-type frequencies of TGTG/TGTG and TGTG/del+del/del between the two groups (χ2=6. 870, P=0. 009). The genotypes of TGTG/del and del/del at rs17235416 were risk factors for TB ( OR=0. 376; 95%CI:0. 178-1. 794 as compared with the TGTG/TGTG genotype in Tibetan people in Qinghai. Conclusion This study suggested that the NRAMP1 gene polymorphisms at rs3731865 and rs1723409 sites had no correlation with the susceptibility to TB in Tibetans in Qinghai. However, the NRAMP1 gene polymorphisms at rs17235416 site were correlated with the susceptibility to TB. The TGTG/del alleles at the rs17235416 site might be the risk factors for tuberculosis in Tibetans in Qinghai.
ABSTRACT
Objective To investigate the neuroprotective effect of miR-181c on hypoxia-preconditioned ischemia in rats and its mechanism.Methods Thirty-nine male SD rats were randomly divided into 5 groups of control group,sham-operated group,middle cerebral artery occlusion (MCAO)group,hypoxia-preconditioned group,hypoxia-preconditioned and MCAO group.Infarct volume and behavioral deficits were quantified.Real-time PCR was applied to detect the expression levels of miR-181c and Western blotting was used to verify the target protein of mt-cox1.Results Under the treatment of hypoxia-preconditioned,the neurological impairment was alleviated and the infarct volume was reduced significantly from 22.50％ ±2.96％ to 16.40％ ±3.13 ％ (t =5.26,P ＜0.01).The expression of miR-181c was decreased significantly in hypoxia-preconditioned and MCAO group than that in MCAO group (1.89 ± 0.14 vs 3.05 ± 0.26,t =6.10,P ＜ 0.01),and the expression of mt-cox1 protein was also significantly decreased (0.54 ± 0.07 vs 0.93 ± 0.04,t =8.01,P ＜ 0.01).Conclusion Hypoxia-preconditioned may attenuate the ischemic injury in SD rats,which may be related to the down-regulation of the expression of miR-181c,therefore increasing the expression of its targeted protein mt-cox1.
ABSTRACT
Objective To investigate the change of aquaporin 2 (AQP2) mRNA and protein levels in renal collecting duct of SD rats after hypoxin caused by rising of the altitude to 4600 m. Methods Forty male SD rats were randomly divided into 4 groups (24 h, 48 h, 72 h and 1 week group), and 10 rats in Xining city were used as control group. All the 40 SD rats were transported to Kekexili Natural Reservation areas (4600 m) in Qinghai province. Rats of four experimental groups were sacrificed and renal tissue samples were harvested at different time point respectively, the control group rats were treated in Xining city (2260 m) as well. The concentration of plasma antidiuretic hormone (ADH) was measured by radioimmunity method. The expression of AQP2 mRNA and proteins was evaluated by real-time fluorescent quantitative-PCR, Western blot and immunofluorescence assay. Results The concentration of plasma ADH was decreased at 24 h and was only 28.5% of that of control group, reaching the lowest concentration at 48 h [(86.94±6.49) μg/L vs (302.5±310.48) μg/L], then it increased gradually and was similar to the control group at 7 d [(306.46±11.14) μg/L vs (302.53±10.48)μg/L, P＞ 0.05]. There were significant differences of the control group with 24 h, 48 h and 72 h groups, respectively[(302.53± 10.48) μg/L vs (142.46±10.57)μg/L, (86.94±6.49)μg/L, (169.65±11.15) μg/L respectively, P＜0.01]. The change of AQP2 gene expression level was consistent with the change of ADH. It was decreased at the begining when exposure to altitude and it reached its lowest level at 48 h. It was then returned to high level similarly to that of the control group at 7 d (0.09±0.01 vs 0.09± 0.008, P＞0.05 ). There were significant differences of the control group with 24 h, 48 h and 72 h group, respectively (0.09±0.008 vs 0.04±0.005, 0.03±0.002, 0.04±0.003 respectively, P＜0.01 ). Conclusions AQP2 expression in the renal collecting duct of SD rats is altered over the period exposed to altitude. It is decreased in the early hypoxia period, and is increased in later period. This change may be related to the intensity of hypoxia, which is mediated by a potential adaptation mechanisms against hypoxia caused by high altitude.