First Report of Pectobacterium polaris Causing Soft Rot on Broccoli in China.

In April 2023, soft rot symptoms were observed in broccoli (Brassica oleracea L. var. italica) commercial fields in Songming County, Yunnan province, China (103°12'E, 25°31'N). The disease incidence in these fields (6 ha in size) was high, exceeding 50%, and it caused significant yield loss. The affected plants displayed characteristic symptoms, with the roots and stems of broccoli becoming soft, yellowish-brown, rotten, and emitting a foul odor. To identify the causal agent, soft rot symptomatic stems were surface sterilized by dipping them in 75% ethanol for 30 seconds, followed by three successive rinses with sterile distilled water. Tissue specimens were then plated onto nutrient agar (NA) plates and incubated at 28°C for 24 hours. (Wang et al. 2022). Three representative bacterial isolates HYC22041801-HYC22041803 from broccoli were selected for further analysis. The colonies on NA plates appeared as white, small, round, and translucent with smooth edges. Physiological and biochemical tests were performed, along with 96 phenotypic screenings using the BIOLOG GENIII microplate system (Biolog, Hayward, CA, USA). Three isolates were negative for D-arabitol, maltose, and sorbitol, but were positive for cellobiose, α-D-glucose, sucrose, glycerol and gentiobiose tests, which are consistent with the reported type strain P. polaris NIBIO1006T (Chen et al. 2021). Total genomic DNA was extracted from three bacterial isolates using the QIAamp DNA Mini Kit (QIAGEN, USA). The 16S rRNA region and nine housekeeping genes (gapA, icdA, mdh, mtlD, pel, pgi, pmrA, proA and rpoS) were amplified with universal primers 27F/1492R (Monciardini et al., 2006) and designed specific primers (Xie et al., 2018), respectively. All amplicons were sequenced and deposited in GenBank with accession numbers ON723841-ON723843 and ON723846-ON723872. The BLASTn analysis of the 16S rRNA amplicons confirmed that the isolates HYC22041801-HYC22041803 belonged to the genus Pectobacterium. Phylogenetic trees based on 16S rRNA gene sequences and multilocus sequence analysis of other nine housekeeping genes of the three isolates were constructed and the results revealed that three isolates clustered with P. polaris type strain NIBIO1006T, which was previously isolated from potato (Dees et al., 2017). To confirm the pathogenicity, nine broccoli seedlings were stab inoculated with a bacterial suspension (108 CFU·ml-1), while sterile distilled liquid LB medium was used as a negative control. The seedlings were kept at 80% relative humidity and 28°C in a growth chamber. Three trials were conducted per isolate (HYC22041801-HYC22041803). After 3 days, the inoculated petioles showed soft rot symptoms similar to those observed initially in the field, while control plants remained asymptomatic. All three isolates were re-isolated successfully from symptomatic tissues to complete Koch's postulates. P. polaris has been previously reported as the causative agent of blackleg in potato in several countries, including Norway, Poland, Russia, and China (Handique et al. 2022; Wang et al. 2022). Additionally, it was reported to cause soft rot in Chinese cabbage in China (Chen et al. 2021). However, this is the first report of P. polaris causing soft rot disease in broccoli in China. This discovery is of great importance for vegetable growers because this bacterium is well established on Cruciferous vegetables in the local area, and effective measures are needed to manage this disease.

Rapid Detection and Quantification of Viable Cells of Pectobacterium brasiliense Using Propidium Monoazide Combined with Real-Time PCR.

Pectobacterium brasiliense (Pbr) has caused significant economic losses in major vegetable production areas in Northern China by causing bacterial soft rot in cash crops such as potatoes and cucumbers. This study aimed to establish a PMA-qPCR detection method for Pbr by screening specific and sensitive primers based on the glu gene and the conserved region of the 23S rRNA gene. Based on the optimized PMA pretreatment conditions, a standard curve was designed and constructed for PMA-qPCR detection (y = -3.391x + 36.28; R2 = 0.99). The amplification efficiency reached 97%, and the lowest detection limit of viable cells was approximately 2 × 102 CFU·mL-1. The feasibility of the PMA-qPCR method was confirmed through a manually simulated viable/dead cell assay under various concentrations. The analysis of potato tubers and cucumber seeds revealed that nine naturally collected seed samples contained a range from 102 to 104 CFU·g-1 viable Pbr bacteria. Furthermore, the system effectively identified changes in the number of pathogenic bacteria in cucumber and potato leaves affected by soft rot throughout the disease period. Overall, the detection and prevention of bacterial soft rot caused by Pbr is crucial.

A mitochondria-targeted fluorescent probe for real-time imaging SO2/H2O2.

Studies have shown that changes in the redox state of cells might be closely related to pathological and physiological processes. Sulfur dioxide and hydrogen peroxide, as a significant redox couple in living cells, are endogenously produced by cells. Here, we report a long-wavelength fluorescent probe to reversibly monitor sulfur dioxide and hydrogen peroxide. This probe (NBD) displayed high selectivity and sensitivity, which could be accumulated in mitochondria for real-time imaging of SO2/H2O2. These results indicated that NBD would be an ideal tool for monitoring the redox cycle state in living cells.

[Effect of dahuang zhechong pill on content of amino acids in hippocampal tissue of ischemic cerebral hemorrhagic rats].

OBJECTIVE: To observe the effect of Dahuang Zhechong Pill (DZP) on the content of amino acids in hippocampal tissue of model rats of ischemic cerebral hemorrhage (ICH). METHODS: Collagenase and heparin were injected into caudate nucleus to establish ICH rat model. The content of glutamic acid (Glu), aspartic acid (Asp) and gamma-aminobutyric acid (GABA) in hippocampal tissue was detected by anti-phase high-performance liquid chromatographic fluorimetry to observe the effect of DZP on the content of amino acids in brain tissue. RESULTS: Three days after modeling, the content of Glu, Asp and GABA was significantly higher in the model group than those in the sham-operation and the normal control group (P < 0.05), for Glu 15.2926 +/- 4.2429 micromol/g vs 8.0057 +/- 1.1227 micromol/g and 8.5040 +/- 1.7794 micromol/g, for Asp 3.6384 +/- 3.1021 micromol/g vs 1.4986 +/- 0.4174 micromol/g and 1.2669 +/- 0.4695 micromol/g, and for GABA 0.3859 +/- 0.1846 micromol/g vs 0.1829 +/- 0.04665 micromol/g and 0.1770 +/- 0.0472 micromol/g. The content of Glu (9.0550 +/- 1.7195 micromol/g), Asp (1.8085 +/- 0.6862 micromol/g) and GABA (0.1993 +/- 0.0424 micromol/g) in hippocampal tissue in the DZP group was reduced significantly, as compared with that in the model group (P <0.05). CONCLUSION: DZP could reduce the release of excitatory amino acids (EAA-Glu, ASP) to balance EAA/inhibitory amino acid (IAA), so as to relieve ICH-induced brain injury.

Effects of electroacupuncture on the contents of NO, ET and T-AOC in the brain tissues of the cerebral hemorrhage model rats.

In the cerebral hemorrhage model rats established by injection of collagenase and heparin into caudate nucleus, the effects of electroacupuncture (EA) on the contents of nitric oxide (NO) and endothelin (ET), and total anti-oxidation capability (T-AOC) in the brain tissues were investigated. It is found that the content of NO in the Shuigou EA group lowered, ET decreased and the T-AOC raised significantly in both the Fengfu EA group and the Shuigou EA group (all P<0.05) as compared with the model group, indicating that acupuncture can reduce the contents of ET and NO, and increase the T-AOC in the brain tissues of the rats with cerebral hemorrhage.

[Effect of Chinese and western medicine integration on spinning behavior of rats with Parkinson disease].

OBJECTIVE: To observe the effect of Chinese and western medicine integration on the spinning behavior of rats with Parkinson disease. METHODS: Model of the lateral Parkinson disease was made with injection of 6-hydroxydopamine (6-OHDA) into the black substance of the right side of the brain, and the model rats were treated with madopar and Chinese herbs for nourishing the liver and kidney, clearing collaterals and detoxification. The rat's spinning behavior was observed, and was compared with the normal control group, madopar group and sham-operation group at the same time. RESULTS: Chinese and western medicine integration could obviously reduce the spinning circles of the rats. CONCLUSION: Chinese and western medicine integration can significantly improve the spinning behavior of the model rats.

[Clinical randomized double-blinded study on treatment of vascular dementia by jiannao yizhi granule].

OBJECTIVE: To observe the effect of Chinese herbal medicine in treating vascular dementia (VD) and to explore the method for therapeutic effect evaluation. METHODS: Multi-center, double-blinded randomize-controlled method was adopted to observe the effect of treatment of 242 patients with VD of mild or middle degree, they were 89 cases in the TCM group, 106 cases in the western medicine group and 47 in the placebo group. Minimental state examination (MMSE), Blessed dementia scoring on TCM symptom classified evaluation were used to evaluate the therapeutic effect after 60 days treatment. RESULTS: The total effective rate of Jiannao Yizhi Granule was 58.4%, showing a better effect than that of the placebo group and the western medicine group respectively. The treatment was superior in holistic regulation and systemic functional state improvement, it could not only improve the mild middle key symptoms of VD and the mental disorder induced reduction of functional activities, but also alleviate or eliminate the peripheral symptoms of VD. CONCLUSION: The effect of treatment of vascular dementia by Jiannao Yizhi Granule is certain and is worth spreading.