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Zhixia Zhuang

Publications and source records attributed to Zhixia Zhuang.

5 recordsLinked to original sources
PubMed2024

Role of the Pseudomonas plecoglossicida fliL gene in immune response of infected hybrid groupers (Epinephelus fuscoguttatus ♀ × Epinephelus lanceolatus ♂).

Pseudomonas plecoglossicida, a gram-negative bacterium, is the main pathogen of visceral white-point disease in marine fish, responsible for substantial economic losses in the aquaculture industry. The FliL protein, involved in torque production of the bacterial flagella motor, is essential for the pathogenicity of a variety of bacteria. In the current study, the fliL gene deletion strain (ΔfliL), fliL gene complement strain (C-ΔfliL), and wild-type strain (NZBD9) were compared to explore the influence of the fliL gene on P. plecoglossicida pathogenicity and its role in host immune response. Results showed that fliL gene deletion increased the survival rate (50%) and reduced white spot disease progression in the hybrid groupers. Moreover, compared to the NZBD9 strain, the ΔfliL strain was consistently associated with lower bacterial loads in the grouper spleen, head kidney, liver, and intestine, coupled with reduced tissue damage. Transcriptomic analysis identified 2 238 differentially expressed genes (DEGs) in the spleens of fish infected with the ΔfliL strain compared to the NZBD9 strain. Based on Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, the DEGs were significantly enriched in seven immune system-associated pathways and three signaling molecule and interaction pathways. Upon infection with the ΔfliL strain, the toll-like receptor (TLR) signaling pathway was activated in the hybrid groupers, leading to the activation of transcription factors (NF-κB and AP1) and cytokines. The expression levels of proinflammatory cytokine-related genes IL-1β, IL-12B, and IL-6 and chemokine-related genes CXCL9, CXCL10, and CCL4 were significantly up-regulated. In conclusion, the fliL gene markedly influenced the pathogenicity of P. plecoglossicida infection in the hybrid groupers. Notably, deletion of fliL gene in P. plecoglossicida induced a robust immune response in the groupers, promoting defense against and elimination of pathogens via an inflammatory response involving multiple cytokines.

Animals↗
PubMed2005

[Separation and identification of metallothionein isoforms and sub-isoforms by liquid chromatography].

A method has been established for the separation and identification of metallothionein (MT) isoforms and sub-isoforms by liquid chromatography. A mixture of rabbit liver MT was separated on a DEAE A-25 weak anion-exchange chromatographic (AEC) column. Inductively coupled plasma-mass spectrometer (ICP-MS) was used for off-line detection of Zn in each fraction. The two main MT isoforms, MT-1 and MT-2, were isolated. The collected MT isoform fractions were then desalted by a homemade Sephadex G-25 size exclusion chromatographic (SEC) column. Afterwards, the sample was separated on a C18 reversed-phase column with UV detection at 210 nm. Different separation conditions were discussed and several sub-isoforms of MT were well separated at pH 2.0. The sub-isoforms were finally characterized by on-line HPLC-ESI-MS. The isoforms and sub-isoforms were well separated on a reversed-phase column under optimized chromatographic conditions and the detection results of ESI-MS were in agreement with the data found in literature. The method developed can be well used for the separation of metallothionein isoforms and sub-isoforms.

Animals↗
PubMed2004

Measurement of chemical oxygen demand (COD) in natural water samples by flow injection ozonation chemiluminescence (FI-CL) technique.

COD determination based on ozone oxidation of alpha-naphthol combined with UV radiation (UV-O3) has been studied in the present work. Utilizing the phenomenon that luminol can be oxidized by the dissolved ozone to produce luminescence, we have established a new method of utilizing aqueous chemiluminescence to determine COD. The kinetics and mechanism of the ozonation reaction of alpha-naphthol have been investigated in order to gain a better understanding of the general applicability and limitation of the technique. Real world samples were analyzed and the results show that the relative error of COD(FI-CL) measurement for water samples was < 10%. Compared with the results of the conventional potassium permanganate method, the COD values of the FI-CL method are consistently higher (0-20% relative). The higher COD values suggest that the ozone-UV system is a more effective oxidation technique.

China↗
PubMed2004

[Characterization method for metallothioneins by reversed-phase liquid chromatography coupled with electrospray ionization mass spectrometry].

Mammalian metallothioneins (MTs) usually have two major isoforms, MT-1 and MT-2, existing in tissues because of the genetic polymorphism. Metallothionein isoforms and sub-isoforms were characterized with a hyphenated technique of reversed-phase liquid chromatography (RPLC) coupled with electrospray ionization mass spectrometry (ESI-MS). The MT-isoform separation was carried out using a C8 narrow-bore column Vydac C8 (250 mm x 2.1 mm i.d., 5 microm, 30 nm). Buffer A was 5 mmol/L ammonium acetate in water (pH 6.0) and buffer B was 5 mmol/L ammonium acetate in methanol-water (1:1, v/v) (pH 6.0). A linear gradient elution was used by increasing buffer B from 10% to 37.5% within 40 min. The flow rate was set at 0.20 mL/min. The tentative formulas of MT isoforms and subisoforms were interpreted with the measured masses at the vicinity of apexes in total ion current chromatogram of ESI-MS and the reference data reported previously. The method was validated with the standard reference materials of MT-1 and MT-2. The results indicated that many MT species interpreted were in good agreement with the reference data reported. The MT sample from rabbit liver was measured with the established method. The results, of which the apo-MT was used by acidification of the sample for simplifying the mass spectra, showed that there were species of MT isoforms and subisoforms in rabbit livers.

Animals↗
PubMed2004

[Characterization of Hg-binding metallothioneins in tissues of rat after oral intake of mercury chloride by size-exclusion chromatography coupled with inductively coupled plasma-mass spectrometry].

Hg concentrations, total metallothioneins (MTs) and metal-binding MTs in tissues of the rat after oral intake of HgCl2 were determined by the inductively coupled plasma-mass spectrometry (ICP-MS), a modifield mecurry saturarion assay and the size-exclusion chormatography (SEC) coupled with ICP-MS, respectively. The results indicated that Hg accumulation in all of the rat tissues, including kidney, liver, testicle, brain, heart, serum and blood plasma, in HgCl2 group significantly increased compared with that in the control group, especiallyin kidney,liver and testicle. A large amount of MTs was inducted in these exposed rat tissues, especially in their kidneys and livers. The metal species binding with MTs obtained with SECICP-MS showed that the fractions of Hg-MTs in both kidney and liver of exposed rat were significantly higher compared with those of the control. In addition, higher amounts of Cu-MTs observed in exposed rat liver and kidney demomstrated the effect of MTs in the homeostatis of Cu and in the detoxification of Hg.

Animals↗