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Fei Zhao

Publications and source records attributed to Fei Zhao.

At least 19 recordsLinked to original sources
PubMed2026

Complete genome sequence of Acinetobacter bacterium strain BZX-2 isolated from hybrid sturgeon.

We report the complete genome sequence of Acinetobacter sp. strain BZX-2, isolated from a hybrid sturgeon (Acipenser baerii ♀ × Acipenser schrenckii ♂). The genome consists of a 3,819,278-bp chromosome with 3,566 predicted protein-coding genes. The genomic characteristics and antibiotic resistance genes identified provide a basis for the prevention and control of sturgeon diseases.

Acinetobacter↗
PubMed2026

Plastome evolution and phylogenomic relationships in Ajuga (Lamiaceae, Ajugoideae).

BACKGROUND: Ajuga is currently known to include approximately 69 species, with a combined distribution extending throughout Eurasia, Africa, and Australia. Its popularity and significance are largely based on an extensive history of medicinal and horticultural use. It is divided into two sections based on morphological characters, and this sectional classification is also reflected in pronounced geographic patterns. Although previous studies have largely focused on Ajuga sect. Ajuga in East Asia, A. sect. Chamaepithys, which ranges from the Mediterranean to Central Asia, remains insufficiently sampled, thereby limiting a comprehensive understanding of infrageneric sectional relationships within the genus. Here, we generated complete plastid genomes for 12 species representing both sections of the genus and used these data to characterize plastome structure and infer evolutionary relationships. RESULTS: In this study, 21 Ajuga plastomes were analyzed, including 12 newly sequenced plastomes and 9 previously published plastomes representing 19 species. Comparative analyses showed that all plastomes exhibited a highly conserved quadripartite structure, with genome sizes ranging from 149,963 to 150,740 bp and GC contents varying from 38.2% to 38.3%. Each plastome contained 133 genes, including 88 protein-coding genes, 37 transfer RNA genes, and 8 ribosomal RNA genes. The boundaries between the inverted repeat (IR) and single-copy (SC) regions were also highly conserved across species. In addition, 796 simple sequence repeats (SSRs), 874 long repeat sequences (LRSs), and 12 highly variable regions (ccsA-ndhD, ndhF-rpl32, petA-psbJ, rpl32-trnL-UAG, rps2-rpoC2, trnH-GUG-psbA, trnK-UUU-rps16, trnP-UGG-psaJ, trnT-UGU-trnL-UAA, ycf15-trnL-CAA, ndhF, and ycf1) were identified among the 21 plastomes. Phylogenetic analyses based on four datasets and conducted using Maximum Likelihood and Bayesian Inference recovered two major clades corresponding to the traditionally recognized sectional classification, with one distributed from the Mediterranean to Central Asia and the other in East Asia. CONCLUSION: This study represents the most comprehensive plastome-based sampling of Ajuga to date, including representative species from the Mediterranean, Central Asia, and East Asia. Our results have significantly enhanced our understanding of its infrageneric relationships. The plastome resources generated in this study provide a valuable foundation for future research on species delimitation, phylogeny, and the evolutionary history of Ajuga.

Phylogeny↗
PubMed2026

Phenotypic and Genotypic Landscape of Sitosterolemia in China: Including a Rare Case With Nephronophthisis.

BACKGROUND: Sitosterolemia (STSL) is a rare autosomal recessive disorder caused by mutations in ABCG5 or ABCG8, characterized by hemolytic anemia, xanthomas, and atherosclerosis. Nephronophthisis (NPHP), another autosomal recessive disorder, is characterized by its devastating progression toward renal failure. METHODS: We analyzed the clinical, laboratory, and genetic data of a Chinese boy with concurrent STSL and NPHP. Separately, we conducted a comprehensive review of the phenotypic and genotypic profiles of all previously reported STSL cases in China. RESULTS: The proband presented with recurrent fever, thrombocytopenia, splenomegaly, and renal dysfunction and was initially misdiagnosed with hemophagocytic lymphohistiocytosis. Genetic testing confirmed biallelic ABCG8 mutations (c.490C>T and c.323-1G>C) and a homozygous NPHP1 deletion. A comprehensive review of 131 Chinese STSL cases (130 from the literature) found that xanthomas, hypercholesterolemia, and elevated low-density lipoprotein cholesterol (LDL-C) were the most common manifestations (each with a prevalence of 82.4%), followed by splenomegaly (32.1%), thrombocytopenia (32.1%), and anemia (30.5%). Hypercholesterolemia and high LDL-C were more common in children, whereas hematologic abnormalities and organ damage were more prevalent in adults. Mutations in ABCG5 accounted for 77.1% of patients. CONCLUSIONS: Genetic testing is crucial when clinical findings conflict with the initial diagnosis. This study summarizes the largest cohort of Chinese STSL patients to date, which may aid in the early recognition and management of this condition.

Humans↗
PubMed2025

STING inhibits LINE-1 retrotransposition through sorting ORF1p to lysosomes for degradation.

The cyclic dinucleotide sensor stimulator of interferon (IFN) genes (STING) is known for its critical role in interferon and inflammatory responses. In addition, STING also has functions independent of interferon induction. In this study, we report that STING restricts the mobilization of the cellular retrotransposon long interspersed nuclear element 1 (LINE-1) independent of cGAS and interferon induction. LINE-1 is the only active autonomous retrotransposable element in the human genome and its transposition can cause genetic and autoimmune diseases. STING inhibition of LINE-1 requires its dimerization. Mechanistically, STING interacts with LINE-1 ORF1p, then the complex translocates to the ER-Golgi intermediate compartment (ERGIC) and the Golgi followed by sorting to Rab7-positive lysosomes for degradation. Our data unveil a function of STING in maintaining host genome integrity by restricting LINE-1 retrotransposition via an IFN-independent mechanism.

Humans↗
PubMed2007

Hydrogencyanamide-bridged one-dimensional polymers built on Mn(III)-Schiff base fragments: synthesis, structure, and magnetism.

The ability of NCNH(-) to construct transition metal coordination polymers and to transmit magnetic coupling was investigated. By introduction of various tetradentate Schiff base ligands (L) and different solvents (S), nine NCNH(-)-bridged manganese(III) coordination complexes were obtained. Their structures can be divided into three types: I) NCNH-bridged chains built on mononuclear [Mn(III)(L)] units, [Mn(III)(L)(mu(1,3)-NCNH)](n) (L=5-Brsalen (1), 5-Clsalen (2)); II) NCNH-bridged chains built on dinuclear [Mn(III) (2)(L)(2)] units, complexes 3-8, [Mn(III) (2)(L)(2)(mu(1,3)-NCNH)]ClO(4)S (L=salen, 5-Fsalen, 5-Clsalen, 5-OCH(3)salen; S=CH(3)OH or C(2)H(5)OH); III) NCNH-bridged Mn(III) dimers linked by hydrogen bonds into a 1D polymer, {[Mn(III)(3-OCH(3)salen)(H(2)O)](2)(mu(1,3)-NCNH)}ClO(4) x 0.5 H(2)O (9, salen=N,N'-bis(salicylidene)-1,2-diaminoethane). In these complexes, the N[triple chemical bond]C--NH(-) resonance structure dominates the bonding mode of the NCNH(-) ligand adopting the mu(1,3)-bridging mode. Magnetic characterization shows that the asymmetric NCNH(-) bridge transmits antiferromagnetic interaction between Mn(III) ions and often favors the weak ferromagnetism caused by spin canting in these one-dimensional chains. However, these complexes exhibit different magnetic behaviors at low temperatures.

Journal Article↗
PubMed2006

Monodisperse lanthanide oxysulfide nanocrystals.

Monodisperse lanthanide oxysulfide nanoplates and short nanorods were synthesized by the thermal decomposition of molecular precursors in the presence of oxygen. The nanoplates have uniform thicknesses and further self-organize to nanowires up to micron scale. The Eu2O2S and Eu3+-doped Gd2O2S nanocrystals both show unusual fluorescence properties obviously differing from the bulk powder phosphors, which are related to the surface-modification effects.

Journal Article↗
PubMed2006

Plasmid-mediated degradation of 4-chloronitrobenzene by newly isolated Pseudomonas putida strain ZWL73.

A strain of Pseudomonas putida ZWL73 was isolated from soil contaminated with chloronitrobenzenes and identified by 16S rDNA sequencing. This bacterium released chloride and ammonia into the medium when grown on 4-chloronitrobenzene (4CNB) as the sole source of carbon, nitrogen and energy. A plasmid designated pZWL73 of approximately 100 kb in this strain was found to be responsible for 4CNB degradation. This was based on the fact that the plasmid-cured strains showed 4CNB- phenotype and the 4CNB+ phenotype could be conjugally transferred. The cell-free extracts of strain ZWL73 exhibited chloronitrobenzene nitroreductase and 2-amino-5-chlorophenol 1, 6-dioxygenase (2A5CPDO) activities, but neither activity was found from that of the plasmid-cured strain. We have also cloned a 4.9-kb EcoRI fragment exhibiting 2A5CPDO activity. Sequencing results revealed beta-subunit (cnbCa) and alpha subunit (cnbCb) of a meta-cleavage dioxygenase, which were subsequently expressed in E. coli with 2A5CPDO activity. The phylogenetic analysis suggested that 2A5CPDO may form a new subgroup in class III meta-cleavage dioxygenase with its close homologs.

Biodegradation, Environmental↗
PubMed2006

Lead toxicity in Brassica pekinensis Rupr.: effect on nitrate assimilation and growth.

Lead is a major heavy-metal contaminant in the environment that has various anthropogenic and natural sources. To study the phytotoxic effects of Pb on the popular vegetable Chinese cabbage (Brassica pekinensis Rupr.) via depression of nitrogen assimilation, pot culture experiments with three concentrations of treatment with Pb (0, 4, and 8 mmol/kg dry soil) were carried out. Our results demonstrated adverse effects of Pb on nitrogen assimilation and plant growth. The addition of Pb in the soil resulted in elevated accumulation of Pb in the shoots of the plants: Pb concentrations of 14.3, 202.3, and 418.2 mg/kg (DW) in the shoots were detected with the 0, 4, and 8 mmol/kg treatments, respectively. Compared to the control, Pb exposure (4 and 8 mmol/kg) significantly decreased shoot nitrate content (71% and 80% of the control), nitrate reductase activity (104% and 49% of the control), and free amino acid content (81% and 82% of the control), indicating decreased nitrogen assimilation in the plants. The effect of Pb also was shown by the progressive decline in shoot biomass with increasing Pb concentration in plant shoots and in the soil. However, at the treatment levels used in this study, lead did not induce visible toxic symptoms. The lowest-concentration Pb treatment (4 mmol/kg) stimulated chlorophyll b content but did not influence chlorophyll a content. The results suggested that the toxicity of Pb to the plants occurred at least partly via depression of nitrogen assimilation.

Amino Acids↗
PubMed2006

In vitro osteogenetic activity of pearl.

In vivo and in vitro studies have shown that shell nacre and hydroxyapatite (HA) are promising bioactive materials for bone repair. In this work, the osteogenetic activity of pearl is evaluated by soaking it in simulated body fluid (SBF) and cell culture, taking shell nacre and HA as control materials at the same time. After soaking in SBF, HA particles were rapidly formed on the surface of pearl, the dissolution of CaCO3 and the binding between organic components and Ca2+ ions in pearl provide favorable conditions for the HA precipitation, and the whole process follows a dissolution-binding-precipitation mechanism. Calcium surplus, not conventional calcium deficiency, is found in HA crystal structure; it implies that type B-HA is formed on pearl surface in this study. HRTEM observation shows that HA is poorly crystallized with so many dislocations and shuttle-like amorphous areas. Cell culture reveals that pearl could stimulate osteoblast proliferation, which proceeded more quickly and smoothly than that on shell nacre and HA, and abundant extracellular matrix occupied the whole pearl surface by 5 days. It is concluded that pearl is a superior osteoinductive material with high osteogenetic activity.

Animals↗
PubMed2006

Distortion product otoacoustic emissions in patients with King-Kopetzky syndrome.

In the present study, mild impairment of cochlear function in patients with King-Kopetzky syndrome was investigated using DPOAEs. A significant decrease in DPOAE levels in both ears was found in patients with King-Kopetzky syndrome compared with the controls after considering the thresholds as a co-variable. It is noteworthy that the global mean levels of DPOAEs were still significantly greater in controls than in patients with matched thresholds. Further frequency analyses showed a significant decrease in DPOAE levels over the mid- and high-frequency range in patients with better hearing thresholds when compared with those in the control group. Moreover, significantly smaller DPOAEs were found in the ears of patients with King-Kopetzky syndrome and without SOAEs, than in such ears of control subjects after considering the thresholds as a co-variable. However, when SOAEs were present there was no difference. Decreases in DPOAE level appear to represent evidence of minor cochlear pathology, and provide a pathological basis for the difficulty of hearing speech in the presence of background noise, which characterizes King-Kopetzky syndrome.

Acoustic Stimulation↗
PubMed2006

[Analysis of differential express gene between keloid and normal skin by suppression subtractive hybridization].

OBJECTIVE: To compare gene express difference of keloid and normal skin tissues by using the suppression subtractive hybridization (SSH) so as to find the differential express gene in keloid. METHODS: mRNA extracted from keloid and normal skin tissues was used as the template to synthesis cDNA of keloid and normal skin. The cDNA of keloid served as a tester, the cDNA of normal skin as a driver. cDNA was digested with Rsa I. Adaptor-ligated tester cDNA was prepared. Then first hybridization, second hybridization and PCR amplification were done. Differentially expressed cDNA was selectively amplified during these reactions. After SSH, the PCR mixture was ligated with T-vector. The positive clones were selected and the insert gene fragments were analyzed. Southern hybridization identified the keloid differential express genes. The positive clones of Southern hybridization were selected, and these sequences were analyzed. The results were compared with that of GeneBank. RESULTS: Thirteen differential genes were found in keloid, of which 11 gene clones have been known their function, and 2 clones have not known their function. CONCLUSION: Keloid differentially expressed gene was screened successfully by SSH.

DNA, Complementary↗
PubMed2005

The study of solution conformation of allatostatins by 2-D NMR and molecular modeling.

More than 70 allatostatins have been isolated from various insects and there is interest in the determination of their active conformation. We have synthesized Dippu-AST 1 (originally isolated from the cockroach Blattella germanica) and studied its conformation in solution by 2-D NMR and molecular modeling. Dippu-AST 1 belongs to the cockroach-type ASTs that have Y/FXFGL-NH(2) as the common C-terminal sequence. We found that Dippu-AST 1 forms a type I' beta-turn conformation in DMSO. We also studied the conformations of Dippu-AST 1 and six cockroach-type allatostatins in water using the molecular dynamics method. When the X amino acid in the consensus sequence Y/FXFGL-NH(2) is Ala or Ser, the allatostatin can form a typical type II beta-turn. If the X is Asp or Asn whose side chain contains a carbonyl, the allatostatin can form a type I, I' or IV beta-turn conformation; if the X is Gly, a closer gamma-turn is adopted. Our study indicates that the turn conformation is ubiquitous in cockroach-type allatostatins.

Amino Acid Sequence↗
PubMed2005

[Inhibition effects of par-4 antisense oligodeoxynucleotide on apoptosis of PC12 cell induced by glutamate is mediated by ERK1/2].

OBJECTIVE: To investigate the inhibition effects of par-4 antisense oligodeoxynucleotide on apoptosis of PC12 cell induced by glutamate and its signal transduction mechanism. METHODS: (1) Cationic lipid-mediated par-4 antisense oligodeoxynucleotide (Par-4-AS-ODN) was transfected into PC12 cells before they were treated with glutamate. Mismatch oligodeoxynucleotide (MS-ODN) were also transfected into cells as controls. (2) Morphological observation and the detection of anti-apoptosis effects of par-4-AS-ODN on PC12 cells were done with the Laser Scanning confocal Microscope by double staining the cells with acridine orange/ethidium bromide (AO/EB), addition to with flow cytometry. (3) Western blot was used to detect the protein levels of par-4 and phosphorylated ERK(1/2) at threonine-202 and Tyrosine-204. RESULTS: (1) Par-4-AS-ODN significantly suppressed up-regulation of the par-4 protein levels induced by glutamate in PC12 cells. (2) Par-4-AS-ODN could resist the decrease of phosphorylated ERK(1/2) (Thr202/Tyr204) induced by glutamate in PC12 cells. (3) Par-4 AS-ODN could inhibit apoptosis of PC12 cells induced by glutamate. But its inhibition effect could be eliminated by PD98059, a selective MEK(1) inhibitor which could inhibit phosphorylation of ERK(1/2). CONCLUSION: Par-4 AS-ODN may inhibit apoptosis of PC12 cells induced by glutamate, and its inhibition effects may be medicated by the activation of ERK(1/2).

Animals↗
PubMed2005

The viability of speech-in-noise audiometric screening using domestic audio equipment.

Speech-in-noise audiometry has potential application as a low-cost, self-screening test for sensorineural hearing loss. To realize this potential, the influence of variations in audio equipment and listening environment need assessment. The present study assessed: 1) the frequency response and distortion produced by a wide range of commercially available audio equipment; 2) the effects of such variations upon test results with normally hearing subjects using a simple, open-set, word-identification test; 3) the effect of distortion on the speech reception threshold using digitally applied distortion; and 4) the reliability of the test in listening environments with different levels of reverberation. In addition, preliminary tests were conducted with elderly listeners. The results indicate that variations in equipment have negligible effects on speech-in-noise audiometry. The only factor that substantially elevated normally hearing listeners' thresholds was high levels of room reverberation when using loudspeaker presentation. Variations in equipment and environment thus present no significant obstacle to the development of a self-administered audiometric screening test based on speech in noise.

Acoustic Stimulation↗
PubMed2005

[Transfection of Lipoxin A4 receptor-like protein gene enhanced the inhibitory effect of Lipoxin A4 on human lung fibroblasts proliferation induced by connective tissue growth factor].

OBJECTIVE: Lipoxin A(4) is formed by the metabolism of arachidonic acid. Anti-inflammatory and anti-proliferative effect of lipoxin A(4) has been shown in many human diseases. Recently, as a novel high affinity receptor for ligand lipoxin A(4), Lipoxin A(4) receptor-like protein (LRLP) has been identified. Currently close attention is paid to the important contribution of connective tissue growth factor (CTGF) in lung fibrosis. The purpose of the study was to transfect LRLP gene into human lung fibroblasts and investigate the mechanism of its enhancing antagonistic effect of Lipoxin A(4) on human lung fibroblasts proliferation induced by connective tissue growth factor. METHODS: Eukaryocytic expression vector pEGFP/LRLP which contained LRLP and green fluorescence protein fusion gene (GFP) was constructed and transfected into human lung fibroblasts (HLF). After selecting with G418, HLF/LRLP cell clone which stably expressed LRLP/GFP fusion protein was isolated and characterized by the laser scanning confocal microscope. Cultured HLF and HLF/LRLP were stimulated for 24 h with CTGF (1 microg/ml) in the presence and absence of pretreatment of Lipoxin A(4) (10.0 nmol/L) for 30 min. Inhibition of cell proliferation was determined by MTT assay. Cell cycle analysis was performed by flow cytometry. Western blot was used to detect the expression of cyclin D(1) protein. Electrophoretic mobility shift assay (EMSA) was employed to detect the DNA binding activity of STAT(3). RESULTS: (1) HLF/LRLP cell clone which stably expressed LRLP and GFP fusion protein was successfully obtained. (2) Proliferation of HLF and HLF/LRLP was induced by 1 microg/ml CTGF. Pretreatment with 10 nm Lipoxin A(4) inhibited the proliferation of HLF and HLF/LRLP. And the inhibitory rate of HLF/LRLP was significantly higher than that of HLF [(54.1 +/- 4.2)%, (21.2 +/- 3.7)%, P < 0.05]. (3) The flow cytometry analysis showed that compared with HLF, more HLF/LRLP were arrested at G(0)/G(1) phase in the presence of pretreatment of Lipoxin A(4). [(76.3 +/- 3.5)%, (60.8 +/- 2.0)%, P < 0.05]. (4) Ten nmol/L Lipoxin A(4) antagonized CTGF induced increase of cyclin D(1) protein expression in HLF and HLF/LRLP. And its antagonistic effect on HLR/LRLP was stronger than that on HLF (P < 0.05). (5) Ten nmol/L Lipoxin A(4) antagonized CTGF induced increase of STAT(3) DNA binding activity, and its antagonistic effect on HLF/LRLP was more powerful than that on HLF (P < 0.05). CONCLUSIONS: Transfection of Lipoxin A(4) receptor-like protein gene enhanced the inhibitory effect of Lipoxin A(4) on human lung fibroblasts proliferation induced by CTGF. Its mechanism might be related to regulation of cyclin D(1) protein expression and STAT(3) DNA binding activity.

Connective Tissue Growth Factor↗