Isolation and identification of Balneatrix alpica from patient′s blood and hot spring water / 中华微生物学和免疫学杂志

Objective:To identify and characterize two Balneatrix alpica strains isolated from a patient′s blood sample (strain X117) and the natural hot spring water in the patient′s residential district (strain GN-1), and to provide experimental evidence for the pathogenic diagnosis of clinical infection caused by this rare pathogen. Methods:Biochemical phenotypic identification, matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS), 16S rRNA gene sequencing, phylogenetic analysis, single-nucleotide polymorphism (SNP) analysis, and genome-wide analysis were performed to accurately determine the taxonomic status of the isolates X117 and GN-1 by using Balneatrix alpica DSM 16621 T as a reference. Microdilution broth method was used to test their antimicrobial susceptibility. The virulence genes carried by them were annotated and analyzed using the virulence factor database (VFDB). Results:Strains X117 and GN-1 formed light yellow or tan colonies with mottled surfaces on Columbia blood agar and chocolate agar plates after 4 d of culture. They were Gram-negative rods and positive for oxidase and indole tests, which were consistent with the characteristics of Balneatrix alpica DSM 16621 T. The phylogenetic analysis based on the 16S rRNA gene showed that the isolates X117 and GN-1 were both Balneatrix alpaca. The average nucleotide identity (ANI) values between the two isolates and Balneatrix alpica DSM 16621 T were 98.44% and 98.41%, respectively, and the digital DNA-DNA hybridization (dDDH) values were both 87.1%. The SNP distance between the two strains was 13, indicating that X117 and GN-1 might belong to the same clone. The antibiotic susceptibility testing showed that all of the three Balneatrix alpica strains were sensitive to the commonly used antibiotics against Gram-negative rods. The virulence genes carried by the three Balneatrix alpica strains were mainly involved in adhesion, invasion, flagella and biofilm formation. Conclusions:This study identified a case of bloodstream infection caused by Balneatrix alpica which was closely related to natural hot spring water. Natural hot spring water migh be an important source of clinical infections caused by this species.

Research on polymorphism of MICA genes in patients with type 1 diabetes mellitus in the Han and Lipopulations in Hainan province / 中华检验医学杂志

Objective To investigate the genetic diversity of MICA, and to analyze the correlation between genetic polymorphisms of MICA and T1DM in population of Han and Li nationalities in Hainan province.Methods This study was performed as a case-control study.Fifty-five individuals with T1DM and Fifty-five healthy controls of Han and Li nationalities from Wuzhishan, Lingshui, Qiongzhong, Baisha, Ledong,Changjiang, Dongfang and Haikou regions in Hainan province(35 Male,20 Female of T1DM of Han;28 Male,27 Female of healthy controls of Han; 33 Male,22 Female of T1DM of Li; 28 Male, 27 Female of healthy controls of Li), were enrolled for the study.MICA allelic variation was analyzed by sequencing-based typing(PCR-SBT).Fisher′s exact test was performed to determine the statistical significance of the distribution and allele frequency of MICA.Results In healthy population,11 MICA-sequence and 5 MICA-STR alleles were found in Han nationality, while 13 MICA-sequence and 5 MICA-STR alleles were detected in Li nationality.The MICA-sequence allele MICA*008:01 and the MICA-STR allele MICA-A5 were most frequently observed in Han nationality[30.85%(29/94)and 41.49%(39/94), respectively],while MICA*002:01 and A4 were the most common in Li nationality[21.57%(22/102) and 36%(36/100), respectively].Among patients with T1DM, 10 MICA-sequence and 5 MICA-STR alleles were detected in Han, and 9 MICA-sequence and 5 MICA-STR alleles were found in Li.MICA*002:01 and A9 were most frequently observed in Han[29%(29/100),29.29%(29/99),respectively], while MICA*012:01, MICA*002:01 and the A4 were the most common in Li[21.15%(22/104), 21.15%(22/104),38.24%(39/102), respectively].The allelic frequency of MICA*002:01, MICA*010, MICA-A5, MICA-A6 and MICA-A9 between the healthy population and T 1DM patients of Han nationality(5.32%,22.34%,41.49 %,9.58%,6.38%, respectively in healthy population;29%,7%, 26.26%,2.02%,29.29%, respectively in T1DM patients), exist significant difference(χ2value were 18.799,9.233,5.218,5.197,16.762, respectively.P value were 0.000,0.002, 0.025,0.024,0.000, respectively.all P<0.05),while no significant difference(all P>0.05)between the healthy population and T1DM patients of Li nationality.Conclusions The most common MICA alleles were MICA*008:01 and MICA-A5 in healthy population of Han nationality, while MICA*002:01 and MICA-A4 in healthy population of Li nationality.MICA*002:01 and MICA-A9 were high frequency in T1DM patients of Han population,while the MICA*010,MICA-A5 and MICA-A6 were low frequency.There was not any MICA alleles associated with T1DM in Li nationality.

Serum TNF-α,IL-1β and IL-6 expression levels and significance of children with severe pneumococcal infection / 国际检验医学杂志

Objective To explore serum tumor necrosis factor-α(TNF-α),interleukin 1β(IL-1β),interleu-kin 6(IL-6)expression levels and clinical significance of children with severe pneumococcal infection.Methods 37 cases of children with severe Streptococcus pneumococcal infection(severe infection group)and 36 cases with normal Streptococcus pneumoniae infection(normal infection group)treated in our hospital from January 2016 to January 2017 were enrolled as the study objects,and 37 cases of healthy children were enrolled as the control group in the same period.The levels of immunoglobulin IgA,IgM,IgG and the levels of TNF-,IL-1 and IL-6 in the serum of all children were detected.Results CD3+,CD4+,CD4+/CD8+,IgA and IgG levels in the severe infection group,the normal infection group were significantly lower than those of the control group (P<0.05).Serum TNF-α,IL-1β and IL-6 levels in the severe infection group were significantly higher than those in the normal infection group,and the normal infection group were higher than the control group(P<0.05).Serum TNF-α,IL-1β and IL-6 levels in acute period of the severe infection group were significantly higher than those in recovery period of the same group and same period of the normal infection group,and the acute period were higher than in recovery period of the same group(P<0.05).IL-1β level in recovery period of the severe infection group were significantly higher than that in recovery period of the normal infection group and the control group(P<0.05).Conclusion Children with severe pneumococcal infection have im-mune dysfunction,and serum TNF-α,IL-1β,IL-6 levels significantly increased.These data suggest that the three can be used as a reference marker for assessing the severity of severe pneumococcal infections.

Prokaryotic expression, purification and enzymatic properties of nuclease P1 / 生物工程学报

To establish a prokaryotic expression and purification protocol for nuclease P1 (NP1), we first obtained a synthetic NP1 by splicing 22 oligonucleotides with overlapping PCR. We constructed and transformed a secretory expression vector pMAL-p4X-NP1 into Escherichia coli host strains T7 Express and Origami B (DE3) separately. Then, the recombinant NP1 was purified by amylose affinity chromatography, and its activity, thermo-stability and metal-ion dependence were investigated systematically. The results indicated that the expressed fusion proteins MBP-NP1 (Maltose binding protein-NP1) existed mainly in soluble form both in host strains T7 Express and Origami B (DE3), but the specific activity of recombinant protein from Origami B(DE3) strain was higher than T7 Express strain (75.48 U/mg : 51.50 U/mg). When the MBP-tag was cleaved by protease Factor Xa, the specific activity both increased up to 258.1 U/mg and 139.2 U/mg. The thermal inactivation experiments demonstrated that the recombinant NP1 was quite stable, and it retained more than 90% of original activity after incubated for 30 min at 80 degrees C. Zn2+ (2.0 mmol/L) could increase enzyme activity (to 119.1%), on the contrary, the enzyme activity was reduced by 2.0 mmol/L Cu2+ (to 63.12%). This research realized the functional expression of NP1 in the prokaryotic system for the first time, and provided an alternative pathway for NP1 preparation.

The Elimination Effect of Propofol on Reactive Oxygen Species in Patients with Acute Craniocerebral Injury / 中国医师杂志

Objective To investigate the elimination effect of propofol on the reactive oxygen species(ROS) in patients with acute craniocerebral injury (ACI). Methods Forty patients with ACI were randomly divided into propofol group receiving propofol anesthesia and ?-OH group as control . Electron spin resonance(ESR) spectroscopy was used to determine the plasma contents of oxygen free radical (OFR), and the plasma contents of lipid peroxides(LPO) and nitrogen oxide (NO) were determined with chemical method. Blood samples were collected before anesthesia and 2, 4 hours after starting operation. Results The plasma contents of NO, OFR and LPO significantly increased before operation in patients with ACI compared with healthy subjects(all P

Effect of weaver gene on biology function of CAD cells / 中国病理生理杂志

AIM: To assess the impact of weaver gene on neuronal development,protein expression and vitality. METHODS: DNA encoding the wild-type and mutant ion channel was introduced into immortalized tyrosine hydroxylase-positive CNS-derived neurons named CAD(Cath.a-differentiated,a variant of Cath.a. Cath.a was established by targeted oncogenesis in transgenic mice) cells. DNA clone, immunostaining and Western blotting were used. Three different concentrations (0 25 mg/L, 0 5 mg/L, or 1 0 mg/L) of Girk2 and wv Girk2 expression plasmids were transfected into the CAD cells. The number of transfected cycling cells, protein synthesis and neurites growth were observed between two groups. RESULTS: The number of transfected cycling CAD cells with high concentration of wv Girk2 reduced to about 60%, compared to Girk2-transfected cells. Low concentration of wv Girk2 did not cause cell death but reduced the protein production of transfected genes. Neurite growth was also affected by wv Girk2. MK-801 and Kir2.3 altered the effect of wv Girk2. CONCLUSION: The results indicate that wv Girk2 functions as a blocker in weaver animals, which blockes the wv Girk2 channel to rescue the cells from death. Our data also suggest that the presence of channels and the level of wv Girk2 may have a significant impact on the fate of cells containing wv Girk2.