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.

Objective To investigate the pathogenic mechanism of Campylobacter jejuni(C.jejuni) associated with Guillain-Barré syndrome(GBS) and provide strategy for gene modification, the cstⅡ gene from 8 GBS-associated C.jejuni strains were compared with that from 3 GBS-unrelated C.jejuni strains, getting the base and amino acid mutations, the changes of secondary structures and finding the region which may be responsible for the pathogenicity of C.jejuni inducing GBS. Methods Three GBS-associated C.jejuni strains isolated from stools of GBS patients in north China were selected and cultured, which has been confirmed as GBS-associated by animal model. After sequencing the genome of them, the nucleotide sequences of cstⅡ gene were got through sequence alignment. The nucleotide sequences and deduced amini acid sequences of 3 GBS-associated cstⅡ genes were compared with that from 3 GBS-unrelated C.jejuni strains through bioinformatics software, getting the base and amino acid mutations, the changes of secondary structures. Other 5 GBS-associated cstⅡ genes were also aligned to know whether the differences we got above makes sense. In this way the genetic differences between two kinds of C.jejuni strains may be found and speculating the gene region related to the pathogenicity of GBS became possible. Results The cstⅡgene of 3 GBS-associated C.jejuni strains were all composed of 876 base pairs. Compared with GBS-unrelated C.jejuni strains, there were 9 consistent mutation sites in cstⅡ gene of LL and QYT stains, leading to 3 consistent amino acid mutation. The amino acid mutation of 114 and 182 sites in LL and QYT stains existed in other 5 GBS-associated C.jejuni strains. The sole amino acid mutation of ZHX strain -169 site, located near the 182 site. The seventh α-helix(165-180 region)of the secondary structure of the amino acid sequence from GBS-associated strains were shorter than that from GBS-unrelated strains, and the shorter regions were opened to form β-sheet or coli, which also existed in other GBS-related strains in this study.75% of the GBS-associated cstⅡ genes were Asn-51, while 25% of the GBS-associated and all of the GBS-unrelated cstⅡ genes were Thr-51.LL strain showed highly identity to other GBS-unrelated strains in this study. Conclusion The 165-180 segment of secondary structures in cstⅡ gene from local 3 GBS-associated C.jejuni strains are probably the responsible region involved in inducing GBS. The senior structure changes in this region may affect the activity of sialyltransferase and the structures of ganglioside epitope, so that the C.jejuni can acquire the pathogenicity of GBS. This finding may give a clue to genetic modified site. The bi-functional cstⅡ of C.jejuni may be related to the pathogenicity of GBS. The cstⅡ of LL strain to some extent represents the characteristics of Asian strains, which may directs strains monitoring.

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.

AIM To establish an HPLC method for the simultaneous content determination of four constituents in Qingzhiyi Tablets (Puerariae lobatae Radix,Phyllanthi Fructus,Salviae miltiorrhizae Radix et Rhizoma,etc.).METHODS The analysis of 50％ methanol extract of this drug was performed on a 30 ℃ thermostatic Kromasil C18 column (4.6 mm × 250 mm,5 μm),with the mobile phase comprising of 0.1％ formic acid-methanol-acetonitrile flowing at 1.0 mL/min in a gradient elution manner,and the detection wavelength was set at 270 nm.RESULTS Gallic acid,puerarin,salvianolic acid B and tanshinone Ⅱ A showed good linear relationships within the ranges of 11.95-382.48,14.23-455.28,10.77-344.68 and 3.89-124.32 μg/mL,whose average recoveries were 99.96％,100.92％,98.87％ and 97.67％ with the RSDs of 1.09％,1.30％,1.11％ and 1.22％,respectively.CONCLUSION This sensitive,simple and accurate method can be used for the quality control of Qingzhiyi Tablets.

Objective:A retrospective analysis was performed on clinical characteristics and deoxyguanosine kinase DGUOK gene mutations in a family with hepatocerebral mitochondrial DNA depletion syndrome (MTDPS). Methods:The clinical data, treatment process and gene detection results of a child with MTDPS in the second hospital of Hebei Medical University in April 2019 were analyzed and summarized.Results:Proband was a girl.From the first week of infantile, she suffered from recurrent hypoglycemia, hyperlactic acid, progressive cholestatic liver dysfunction, coagulopathy, difficult feeding, slow growth of body mass, microcephaly, hypotonia, and gradul intermittent binocular tremors, and eventually failed to thrive.Gene testing identified two compound heterozygous mutations c. 42-c.43insTTCA(p.F15fs129X)/c.808-1(IVS6)G>A in DGUOK gene.The former was a frame-shift mutation resulted in truncated protein and the later was a splicing mutation resulted in abnormal splicing.Each parent was a heterozygous carrier, and there were no mutations in the two sites with her elder sister. Conclusions:Both mutations were first reported worldwide. DGUOK gene mutations with MTDPS are important causes of infant liver failure.When hypoglycemia, hyperlactic acidemia and liver dysfunction occur in newborn and infant, MTDPS related gene DGUOK gene sequencing screening should be considered for early definitive diagnosis, or, when acute liver failure happen in infant and childhood, neuromuscular involvement is insufficient.

Objective To investigate the Camtrylobacterjejuni's risk factors which were associated with the development of Guillain-Barre syndrome( GBS), the galE gene of C. jejuni strains were sequenced and the sequencing results were compared with other C. jejuni strains. Methods Selecting three GBS-asso-ciated C.jejuni strains isolated from stools of GBS patients who had been diagnosed as AMAN pattern by clin-ical and electrophysiological test from Hebei province, China. After sequencing galE gene, the results were spliced and assembled into a complete sequence by the terminals overlapped each other. The sequences of galE gene were compared with the corresponding sequences in GenBank to find the mutation and constructed the phylogenetic tree. Results The variation frequency of galE sequences of GBS-associated C. jejuni were higher than that of non-GBS-associated C. jejuni. The phylogenetic analysis demonstrated that each of the three C. jejuni strains was separately genetically closed to three strains which sequences have published in GenBank. The alignment with the related sequence of NCTC11168 shows that there are 4 same mutations in the galE gene of the three C. jejuni strains. The phylogenic tree reflected the regional feature of C. jejuni. Conclusion The probability of sequence variation of galE of GBS-associated C.jejuni is significantly higher than non-GBS-associated C. jejuni strains, the relation between the variation and GBS-pathogenesis remains to be further confirmed. The mutations found in the three C. jejuni strains established the foundation for ex-ploring the biologically characteristic of GBS-associated C. jejuni strains.

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.

Objective:To investigate clinical characteristics and ABCB11 gene mutations in probands suffering from progressive familial intrahepatic cholestasis type 2(PFIC2). Methods:The clinical data involving manifestations and laboratory examinations of 2 probands with PFIC2 admitted to Pediatric Digestive and liver Clinic in Second Hospital of Hebei Medical University during January 2017 to December 2018 were retrospectively analyzed.Target capture high-throughput sequencing, genome-wide gene copy number variation(CNV) detection and validation were performed on probands and their parental DNA.Results:The age of onset for the 2 probands ranged from 2 to 5 months, and they had hepatosplenomegaly, severe cholestasis, pruritus, and binding bilirubin/ total bilirubin (proband 1: 51.8%-77.5%, proband 2: 47.1%-66.5%). Bile acid and aminotransferase[mainly aspartate transaminase (AST)] increased, but γ-glutamyltransferase(GGT) remained normal.Compound heterozygous mutations of ABCBll gene were discovered in proband 1: single strand deletion/c.3213+ 5G>A splicing mutation, and deletion mutation were spontaneous mutation.A total of 2.256 Mb(chr2 2q24.3q31.1)was missing, whereas splicing mutation was originated from her father.Polymorphisms with Val444Ala(T1331C)and Ala1028Ala(A3084G)were proved in proband 1.Compound heterozygous mutations of ABCB11 gene were revealed in proband 2: c.1483A>G(p.R495G)/c.2594C>T(p.A865V), and both parents were heterozygous carriers.Single-strand 2.256 Mb deletion in proband 1 and 2 mutations in proband 2 were unreported new mutations worldwide. Conclusions:In clinical work, children with cholestasis, elevated bile acid and transaminase(mainly AST), but normal GGT, should be detected for PFIC genes as soon as possible.

Diabetic neuropathic pain (DNP) is the most common disabling complication of diabetes. Emerging evidence has linked the pathogenesis of DNP to the aberrant sprouting of sensory axons into the epidermal area; however, the underlying molecular events remain poorly understood. Here we found that an axon guidance molecule, Netrin-3 (Ntn-3), was expressed in the sensory neurons of mouse dorsal root ganglia (DRGs), and downregulation of Ntn-3 expression was highly correlated with the severity of DNP in a diabetic mouse model. Genetic ablation of Ntn-3 increased the intra-epidermal sprouting of sensory axons and worsened the DNP in diabetic mice. In contrast, the elevation of Ntn-3 levels in DRGs significantly inhibited the intra-epidermal axon sprouting and alleviated DNP in diabetic mice. In conclusion, our studies identified Ntn-3 as an important regulator of DNP pathogenesis by gating the aberrant sprouting of sensory axons, indicating that Ntn-3 is a potential druggable target for DNP treatment.
Mice ; Animals ; Diabetes Mellitus, Experimental/metabolism* ; Axons/physiology* ; Diabetic Neuropathies ; Sensory Receptor Cells/metabolism* ; Neuralgia/metabolism*