AIM:To investigate the role of minocycline on glutamate uptake in the periventricular zone and its putative mechanism after hypoxic exposure in neonatal rats.METHODS: A model of hypoxic-ischemic brain damage (HIBD) was developed by putting postnatal 1 d rat pups in 5%O2 for 3.5 h.The glutamate level in periventricular zone was measured by liquid chromatography coupled with tandem mass spectrometry assay ( LC-MS/MS) after hypoxic exposure for 4 h and 1 d.The dynamic changes of glutamate transporters EAAT1, and EAAT2 during developmental period in periventricular zone were determined by Western blot.Moreover, the expression of EAAT1, EAAT2, Iba-1, IL-1β, TNF-αand TGF-β1 was also detected by Western blot after hypoxic exposure for 4 h and 1 d in that region.The effects of mino-cycline on all parameters mentioned above were tested after minocycline treatment at the same time points and in the same region.RESULTS:After hypoxic exposure, glutamate level was increased, but it was decreased after minocycline treat-ment.EAAT1 and EAAT2 kept a low expression level at the first postnatal week, but a predominant elevation was found at the end of the second postnatal week.The expression of EAAT1, EAAT2, Iba-1, IL-1βand TGF-β1 was increased at 1 d after hypoxic exposure.EAAT1 and TNF-αexpression was significantly up-regulated, while EAAT2 was down-regulated af-ter minocycline treatment.CONCLUSION: Minocycline inhibits the increase in the glutamate level after hypoxia in periventricular region of the neonatal rats.The mechanism may relate to the selective regulation of glutamate transporters, rather than the inhibition of neuroinflammation in periventricular zone.

Objective To investigate the molecular size distribution and the structure of group B me-ningococcal capsular polysaccharides for the development of vaccines .Methods The molecular size distribution of group B meningococcal capsular polysaccharides was analyzed by chromatography on a Sepharose CL -4B col-umn.The molecular weight of repeat units were measured by matrix assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS).The structural characteristics of group B meningococcal capsular polysaccharides were analyzed by nuclear magnetic resonance ( NMR) based on the chemical shift of all charac-teristic protons by using group C meningococcal capsular polysaccharides and sialic acid as the controls .Results The KD value of group B meningococcal capsular polysaccharides extracted from 15 strains were ranged from 0.60 to 0.76.The molecular weight of repeat units was 284, which was identical to the theoretical value .The group B meningococcal capsular polysaccharides were 2→8 linked homopolymers of sialic acid lacking O-acetyl groups.Conclusion The group B meningococcal capsular polysaccharides had lower molecular weights , which might result in their poor immunogenicity .The structure of group B meningococcal capsular polysaccharides could be quickly and accurately analyzed by NMR technology .

Objective To study the expression of zinc finger and BTB domain containing 20 (ZBTB20) in peripheral blood B cells of the patients with systemic lupus erythematosus (SLE),and to investigate its clinical significance in SLE.Methods The ZBTB20 mRNA expression level in peripheral blood CD19+B cells of 36 cases of SLE (SLE group) and 30 healthy controls(control group) was detected by RT-PCR.The ZBTB20 protein level was detected by western blot;the proportion of B cell subset was measured by flow cytometry.Then the relationship between the ZBTB20 mRNA expression with B cells subset proportion change and its correlation with clinical indicators[anti-dsDNA antibody,immunoglobulin G (IgG),anti-nucleosome antibody (ANA) and anti-extractable nuclear antigen (ENA) antibody] in SLE patients were analyzed.Results The expression level of ZBTB20 mRNA in peripheral blood CD19+B cells of the SLE group was significantly higher than that of the control group (P＜0.05).The peripheral blood ZBTB20 protein level was higher than that of the control group (P＜0.05);the peripheral blood B cells subsets and CD19+ B cells proportion in the SLE patients were decreased,while the CD19-CD138+ plasmocytes/CD19+ B cells ratio and CD19-CD138+ plasmocytes proportion were significantly increased (P＜0.05).The expression level of ZBTB20 mRNA in B cells of SLE patients was positively correlated with the ratio of CD19-CD138+ plasmocytes/CD19+ B cells (P＜0.05).The expression of ZBTB20 mRNA was positively correlated with anti-ds-DNA antibody,ANA and anti-ENA antibody (P＜0.05).Conclusion ZBTB20 might participate in the pathogenesis of SLE possibly via promoting B cells differentiation.

Objective: To explore the phenotypic and genotypic characteristics in Chinese children with classic pantothenate kinase-associated neurodegeneration (PKAN). Method: The clinical, radiographic and genetic data of all PKAN patients diagnosed at pediatric department of Peking University First Hospital from November 2006 to December 2016 were retrospectively collected and analyzed. Result: Twenty patients with classic PKAN were included in the study. The median age at onset was 3.5 years (ranging from 1.0 to 10.0 years), and the most common initial symptom was gait disturbance (16 cases). At the last evaluation, the clinical features were limbs dystonia (20 cases), dysarthria (16 cases), dysphagia (11 cases), pyramidal sign (7 cases), mental regression (3 cases) and pigmentary retinopathy (5 cases). For those classic PKAN patients, the median time from onset of disease to loss of independent ambulation was 6.9 years (ranging from 2.0 to 12.0 years). Imaging data showed, except "eye of tiger" in MRI (19 cases), globus pallidus calcification in CT was also found in four patients. In gene testing, 26 different mutations in PANK2 gene were identified, and 16 of 26 were novel mutations. Moreover, c. 1502T>C (p.Ile501Asn) was the most common mutation (4 cases). Conclusion Dystonia is the major neurologic feature of classic PKAN. Disease progression is rapid, with loss of independent ambulation within 10 years after onset. Except "eye of tiger" in MRI, globus pallidus calcification in CT may be another imaging feature of PKAN.Sixteen novel mutations of PANK2 gene were identified in the study.