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Cyclin-dependent kinase 5 (Cdk5) activity is specifically active in neurogenesis, and Cdk5 and neocortical neurons migration related biomarker are expressed in Cos-7 cells. However, the function of Cdk5 on the transformation of immortalized Cos-7 cells into neuronal-like cells is not clear.

The Gram-negative bacterium Riemerella anatipestifer CH-2 is resistant to lincosamides, having a lincomycin (LCM) minimum inhibitory concentration (MIC) of 128 µg/mL. The G148_1775 gene of R. anatipestifer CH-2, designated lnu (H), encodes a 260-amino acid protein with ≤41% identity to other reported lincosamide nucleotidylyltransferases. Escherichia coli Rosetta TM (DE3) containing the pBAD24- lnu (H) plasmid showed four- and two-fold increases in the MICs of LCM and clindamycin (CLI), respectively. A kinetic assay of the purified Lnu(H) enzyme for LCM and CLI showed that the protein could inactive lincosamides. Mass spectrometry analysis demonstrated that the Lnu(H) enzyme catalysed adenylylation of lincosamides. In addition, an lnu (H) gene deletion strain exhibited 512- and 32-fold decreases in LCM and CLI MICs, respectively. The wild-type level of lincosamide resistance could be restored by complementation with a shuttle plasmid carrying the lnu (H) gene. The transformant R. anatipestifer ATCC 11845 [ lnu (H)] acquired by natural transformation also exhibited high-level lincosamide resistance. Moreover, among 175 R. anatipestifer field isolates, 56 (32.0%) were positive for the lnu (H) gene by PCR. In conclusion, Lnu(H) is a novel lincosamide nucleotidylyltransferase that inactivates LCM and CLI by nucleotidylylation, thus conferring high-level lincosamide resistance to R. anatipestifer CH-2. [ABSTRACT FROM AUTHOR]

As an important part of the soil microbial system, fungi can clearly indicate changes in the soil environment.Human activities in the city can easily affect the soil condition, so the phenomenon of artificial heavy metal enrichment often appears in urban soil. The objective of this study was to analyze the fungal community structure in different urban functional areas and to determine the effect of heavy metal content in different urban functional areas on the soil fungal community structure. This study provides theoretical basis for protecting and repairing the urban soil ecosystem and transforming and improving urban environmental quality. Soil samples from eight sampling sites in five functional areas of Beibei District in Chongqing were taken as the research objects. The diversity and community structure of fungi in soil were studied using high-throughput sequencing technology. The content of Cd and Hg in the soil of different functional areas in Beibei District exceeded the environmental background value of Chongqing. The 20-40 cm and 40-60 cm soil layers of JD were slightly polluted. The 20-40 cm soil layer and 0-20 cm soil layer of JLD and ZYY, respectively, were in the alerting state of heavy metal pollution. The Sobs index, Chao 1 index, and Ace index of most sampling points decreased with the increase in soil depth. The NMDS analysis showed that the composition of fungal communities between the 0-20 cm and 20-40 cm soil depths in both JD and ZYY were quite different. From the perspective of community composition, Ascomycota was the most abundant phylum in the soil, followed by unclassified _k _Fungi and Basidiomycota. At the genus level, unclassified_k_Fungi , unclassified_p_Ascomycota , unclassified_o_Sordariales , Scopuloides , Robillarda , and Dactylonectria had higher abundances. The redundancy analysis (RDA) showed that Pb and Zn had the greatest effect on the samples, and the effect on the fungal community structure was significantly different. This study has deepened the understanding of the relationship between the content of heavy metals in different urban functional areas and the structure of fungal communities and has provided a scientific basis for the rational use and planning of urban soil.

The aim of the present paper was to study the role of sodium calcium exchanger (NCX) in the generation of action potentials (APs) in cardiomyocytes during early developmental stage (EDS). The precisely dated embryonic hearts of C57 mice were dissected and enzymatically dissociated to single cells. The changes of APs were recorded by whole-cell patch-clamp technique before and after administration of NCX specific blockers KB-R7943 (5 μmol/L) and SEA0400 (1 μmol/L). The results showed that, both KB-R7943 and SEA0400 had potent negative chronotropic effects on APs of pacemaker-like cells, while such effects were only observed in some ventricular-like cardiomyocytes. The negative chronotropic effect of KB-R7943 on ventricular-like cardiomyocytes was accompanied by shortening of AP duration (APD), whereas such an effect of SEA0400 was paralleled by decrease in velocity of diastolic depolarization (Vdd). From embryonic day 9.5 (E9.5) to E10.5, the negative chronotropic effects of KB-R7943 and SEA0400 on ventricular-like APs of embryonic cardiomyocytes gradually disappeared. These results suggest that, in the short-term development of early embryo, the function of NCX may experience developmental changes as evidenced by different roles of NCX in autorhythmicity and APs generation, indicating that NCX function varies with different conditions of cardiomyocytes.

To scientifically evaluate the intervention effect of Chinese medicine preventive administration(combined use of Huo-xiang Zhengqi Oral Liquid and Jinhao Jiere Granules) on community population in the case of coronavirus disease 2019(COVID-19), a large cohort, prospective, randomized, and parallel-controlled clinical study was conducted. Total 22 065 subjects were included and randomly divided into 2 groups. The non-intervention group was given health guidance only, while the traditional Chinese medicine(TCM) intervention group was given two coordinated TCM in addition to health guidance. The medical instructions were as follows. Huoxiang Zhengqi Oral Liquid: oral before meals, 10 mL/time, 2 times/day, a course of 5 days. Jinhao Jiere Granules: dissolve in boiling water and take after meals, 8 g/time, 2 times/day, a course of 5 days, followed up for 14 days, respectively. The study found that with the intake of medication, the incidence rate of TCM intervention group was basically maintained at a low and continuous stable level(0.01%-0.02%), while the non-intervention group showed an overall trend of continuous growth(0.02%-0.18%) from 3 to 14 days. No suspected or confirmed COVID-19 case occurred in either group. There were 2 cases of colds in the TCM intervention group and 26 cases in the non-intervention group. The incidence of colds in the TCM intervention group was significantly lower(P<0.05) than that in the non-intervention group. In the population of 16-60 years old, the incidence rate of non-intervention and intervention groups were 0.01% and 0.25%, respectively. The difference of colds incidence between the two groups was statistically significant(P<0.05). In the population older than 60 years old, they were 0.04% and 0.21%, respectively. The incidence of colds in the non-intervention group was higher than that in the intervention group, but not reaching statistical difference. The protection rate of TCM for the whole population was 91.8%, especially for the population of age 16-60(95.0%). It was suggested that TCM intervention(combined use of Huoxiang Zhengqi Oral Liquid and Jinhao Jiere Granules) could effectively protect community residents against respiratory diseases, such as colds, which was worthy of promotion in the community. In addition, in terms of safety, the incidence of adverse events and adverse reactions in the TCM intervention group was relatively low, which was basically consistent with the drug instructions.

To investigate tetracycline resistance and resistant genotype in Riemerella anatipestifer , the tetracycline susceptibility of 212 R. anatipestifer isolates from China between 2011 and 2017 was tested. The results showed that 192 of 212 (90.6%) R. anatipestifer isolates exhibited resistance to tetracycline (the MICs ranged from 4 to 256 μg/ml). The results of PCR detection showed that, 170 of 212 (80.2%) R. anatipestifer isolates possessed the tet (X) gene. Other genes, including tet (A), tet (M), tet (Q), tet (O), tet (B), and tet (O/W/32/O), were found at frequencies of 20.8, 4.7, 1.4, 0.9, 0.9, and 0.5%, respectively. However, tet (C), tet (E), tet (G), tet (K), and tet (W) were not detected in any isolate. In these tet gene positive strains, 31 (14.6%), 2 (0.9%), 5 (2.4%), 1 (0.5%), 3 (1.4%) were detected containing tet (A)/ tet (X), tet (M)/ tet (O), tet (M)/ tet (X), tet (O)/ tet (X), and tet (Q)/ tet (X) simultaneously, respectively. One isolates, R131, unexpectedly contained three tet genes, i.e., tet (M), tet (O), and tet (X). Sequence analysis of the tet gene ORFs cloned from R. anatipestifer isolates confirmed that tet (A), tet (B), tet (M), tet (O), tet (Q) and an unusual mosaic tet gene tet (O/W/32/O) were present in R. anatipestifer . The MIC results of R. anatipestifer ATCC 11845 transconjugants carrying tet (A), tet (B), tet (M), tet (O), tet (O/W/32/O), tet (Q), and tet (X) genes exhibited tetracycline resistance with MIC values ranging from 4 to 64 μg/ml. Additionally, the tet (X) gene could transfer into susceptible strain via natural transformation (transformation frequencies of ~10 -6 ). In conclusion, the tet (A), tet (B), tet (M), tet (O), tet (O/W/32/O), tet (Q), and tet (X) genes were found and conferred tetracycline resistance in R. anatipestifer isolates. Moreover, the tet (X) is the main mechanism of tetracycline resistance in R. anatipestifer isolates. To our knowledge, this is the first report of tet (A), tet (B), tet (M), tet (O), tet (Q), and mosaic gene tet (O/W/32/O) in R. anatipestifer .