Ethnicity and sex-specific 99th percentile upper reference limits of high-sensitivity cardiac troponin I among adults in Xinjiang, China.

OBJECTIVES: To determine the 99th percentile upper reference limit (URL) of high-sensitivity cardiac troponin I (hs-cTnI) in a healthy population in Xinjiang, China, and investigate the impact of ethnicity, sex, and age on this limit. DESIGN AND METHODS: From September 2018 to March 2022, 5,090 Han and Uyghur adults aged 20-79 years were recruited. After questionnaire screening, 2,970 participants with physical and/or laboratory normality were enrolled. Participants recruited between September 2018 and October 2021 (2,109/2,970) were evaluated by ARCHITECTi2000 to determine the 99th percentile URL of hs-cTnI. The results were then validated in 861/2,970 participants recruited from November 2021 to March 2022. A criterion of ≤ 10% of test results falling outside the original determined value was used to determine whether the newly established reference intervals were valid. RESULTS: The hs-cTnI concentration was higher among Uyghurs than among Han participants (p < 0.001). The 99th percentile URLs were 17.52 ng/L for all participants, 18.96 ng/L for Uyghur, and 16.93 ng/L for Han. Hs-cTnI concentration was also correlated with sex and age. In the Han and Uyghur groups, male participants had a higher hs-cTnI concentration than female participants (p < 0.001); the 99th percentile URLs of hs-cTnI among male and female participants were 17.80 vs. 13.67 ng/L and 19.47 vs. 16.52 ng/L, respectively. Stratified by age, hs-cTnI concentrations were higher in participants aged > 60 years than in those of other age categories (p < 0.001), in both the Han and Uyghur groups. Finally, <2% of these test results exceeded the newly established reference, validating the results. CONCLUSIONS: This study established the 99th percentile URLs of hs-cTnI in the Xinjiang. Ethnicity and sex influence the value and should be considered.

Complete nucleotide sequence of plasmid pND6-2 from Pseudomonas putida ND6 and characterization of conjugative genes.

Pseudomonas putida ND6 was shown to be capable of growth using naphthalene as sole carbon and energy sources. One plasmid from this strain, pND6-1, which was associated with the metabolism of naphthalene, was characterized; and the complete nucleotide sequence (101,858bp) and annotation of the plasmid were reported previously. In this paper, another plasmid (117,003bp) from P. putida ND6, pND6-2, was sequenced and 136 putative coding sequences (CDSs) were annotated. Among them, 9 CDSs were predicted to be involved in replication and partition of the plasmid, 32 CDSs encoded proteins associated with plasmid conjugative transfer, 2 CDSs encoded transcriptional regulators, 9 CDSs were necessary for DNA-associated function (including metabolism, recombination and repair), and 5 CDSs encoded proteins associated with other functions. The filter matting experiment indicated that pND6-2 is a helper plasmid, which could assist the naphthalene catabolic plasmid pND6-1 without any conjugative genes being transferred from P. putida ND6 to Escherichia coli AD256.

Complete genome sequence of the naphthalene-degrading Pseudomonas putida strain ND6.

Pseudomonas putida strain ND6 is an efficient naphthalene-degrading bacterium. The complete genome of strain ND6 was sequenced and annotated. The genes encoding the enzymes involved in catechol degradation by the ortho-cleavage pathway were found in the chromosomal sequence, which indicated that strain ND6 is able to metabolize naphthalene by the catechol meta- and ortho-cleavage pathways.

[Purification and characterization of fibrinolytic enzyme from Bacillus subtilis BS-26].

OBJECTIVE: Thrombolytic therapy is a safe and effective treatment for thrombotic diseases. Microorganisms are possible sources of thrombolytic drugs. We purified and characterized fibrinolytic enzyme produced by Bacillus subtilis strain BS-26. METHODS: We examined the fibrinolytic enzyme activity by fibrin plate and purified fibrinolytic enzyme by ammonium sulfate fractional precipitation, anion-exchange chromatography on DEAE-Sepharose Fast Flow and preparative PAGE. RESULTS: The fibrinolytic enzyme of the strain BS-26 was stable blow 50 degrees C and pH5.0-11.0, the optimal temperature was 42 degrees C and optimal pH was 9.0. Ca2+ and Mg2+ ions enhanced the fibrinolytic activity, whereas Cu2+ completely inhibited the enzyme. Phenylmethylsulfonyl fluoride (174.2 microg/mL), chicken ovomucoid (1000 microg/mL) and soybean trypsin inhibitor (1000 microg/mL) could inhibit enzyme activity, which indicated that the enzyme belonged to serine protease group. On plasminogen-free fibrin plates and plasminogen fibrin plates, the fibrinolytic activity had no obvious difference, indicating that the enzyme was a fibrinolytic enzyme which degraded fibrin directly, but not a plasminogen activator which degraded fibrin by activating plasminogen. A fibrinolytic enzyme was purified from the fermentation broth with recovery yield of 3.2%, purification factor of 41.0 fold and the specific activity 8750.0 U/mg. SDS-PAGE analysis of the purified protein showed only one band with molecular mass of 32 kDa. CONCLUSION: A single fibrinolytic enzyme was purified, which provided the basis for large-scale production of fibrinolytic enzyme.