Pyridine degradation characteristics of Rhodococcus sp. LV4 under high salinity conditions / 生物工程学报

Biodegradation of pyridine pollutant by microorganisms is one of the economical and effective methods to solve the environmental pollution of pyridine under high salinity conditions. To this end, screening of microorganisms with pyridine degradation capability and high salinity tolerance is an important prerequisite. In this paper, a salt-resistant pyridine degradation bacterium was isolated from the activated sludge of Shanxi coking wastewater treatment plant, and identified as a bacterium belonging to Rhodococcus on the basis of colony morphology and 16S rDNA gene phylogenetic analysis. Salt tolerance experiment showed that strain LV4 could grow and degrade pyridine with the initial concentration of 500 mg/L completely in 0%-6% saline environment. However, when the salinity was higher than 4%, strain LV4 grew slowly and the degradation time of pyridine by strain LV4 was significantly prolonged. Scanning electron microscopy showed that the cell division of strain LV4 became slower, and more granular extracellular polymeric substance (EPS) was induced to secrete in high salinity environment. When the salinity was not higher than 4%, strain LV4 responded to the high salinity environment mainly through increasing the protein content in EPS. The optimum conditions for pyridine degradation by strain LV4 at 4% salinity were 30 ℃, pH 7.0 and 120 r/min (DO 10.30 mg/L). Under these optimal conditions, strain LV4 could completely degrade pyridine with an initial concentration of 500 mg/L at a maximum rate of (29.10±0.18) mg/(L·h) after 12 h adaptation period, and the total organic carbon (TOC) removal efficiency reached 88.36%, indicating that stain LV4 has a good mineralization effect on pyridine. By analyzing the intermediate products in pyridine degradation process, it was speculated that strain LV4 achieved pyridine ring opening and degradation mainly through two metabolic pathways: pyridine-ring hydroxylation and pyridine-ring hydrogenation. The rapid degradation of pyridine by strain LV4 in high salinity environment indicates its application potential in the pollution control of high salinity pyridine environment.

Morphological characteristics of bone marrow and peripheral blood in 1 151 cases diagnosed with de novo acute leukemia / 中华检验医学杂志

Objective:To observe and analyze the morphological characteristic of bone marrow and peripheral blood in patients diagnosed with de novo acute leukemia.Methods:From October 1, 2015 to December 31, 2021, 1151 patients aged 47 (26, 62) years, consisting of 602 males and 549 females with newly diagnosed acute leukemia in the Department of Hematology, Affiliated Hospital of Xuzhou Medical University, were collected to preform the morphological analysis in bone marrow and peripheral blood smears. Based on the comprehensive diagnosis results of morphology, immunology, cytogenetics, and molecular biology, comparison between acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL), AML with RUNX1-RUNXITI gene, AML with CBFβ/MYH11 gene, acute promyelocytic leukemia (APL) with PML/RARA gene, AML with NPM1 gene, the rest of the AML, Ph+ALL and Ph-ALL were performed by Chi-square test along with analysis of the differences in the ratio of wood bundle cells, pseudo-Chediak-Higashi (PCH) inclusions, cytoplasmic small particles, nuclear notches, leukemia cells with cup-like changes (cup cells); as well as the differences in the micromeganuclei, early immature granulocytes, plasma cells, high eosinophils and other accompanying cells and the distribution of "grape-like" aggregation. Finally, the morphological characteristics of acute leukemia cells, the appearance and arrangement of accompanying cells were summarized.Results:Between AML and ALL, there were statistically significant differences in cytoplasmic Auer bodies[(45.5%, 0%), χ 2=211.400, P<0.01], PCH inclusion bodies[(28.9%, 0%), χ 2=114.100, P<0.01], cytoplasmic fine particles[(20.7%, 2.9%), χ 2=53.798, P<0.01], nuclear notches[(0.7%, 6.1%), χ 2=30.906, P<0.01], and goblet cells[(4.9%, 0.3%), χ 2=13.495, P<0.01], micromegakaryus [(22.4%, 0.3%), χ 2=80.398, P<0.01], plasma cells[(87.6%, 10.6%), χ 2=604.241, P<0.01], hyperacidophils[(15.3%, 1.0%), χ 2=46.116, P<0.01] showed significant differences in the "grape-like" aggregation distribution. In AML with RUNX1-RUNXITI gene, the changes of vacuoles and PCH inclusion bodies are more obvious; in AML with CBFβ/MYH11 gene, the increase of hypereosinophils is more obvious; in APL with PML/RARA gene, the increase of woodbundle is more obvious. The morphology of nuclei chromatin, nucleolus, and vacuoles were also different among the groups. Comparison between Ph+ALL and Ph-ALL showed that Ph+ALL was more prone to develop early immature granulocytes and plasma cells (all P<0.05). Conclusion:There are significant differences between AML and ALL in the characteristics of leukemia cells, the regularity of accompanying cells, and the aggregation and distribution patterns. The subtypes of AML with specific genetic abnormalities have their own characteristics in the appearance of vacuoles, PCH inclusions, hypereosinophils, woodbundle cells, and goblet cells. Ph+ALL is more prone to present early immature granulocytes and plasma cells.