Publications by authors named "Xi-Fen Zhang"

Article Synopsis
  • The study aimed to observe skin surface microcirculation at specific acupoints in women with primary dysmenorrhea using laser speckle contrast imaging (LSCI) to support acupuncture-moxibustion treatment decisions.
  • A total of 193 female college students participated, with 99 in a normal group and 94 with dysmenorrhea, and measurements were taken before menstruation, on the first day, and three days after menstruation.
  • Results showed increased blood flow at certain acupoints during menstruation in the dysmenorrhea group compared to the normal group but lower blood flow at other acupoints three days post-menstruation, highlighting potential targets for acupuncture treatment.
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Sterigmatocystin (STE) is a common hepatotoxic and nephrotoxic contaminant in cereals, however, its phytotoxicity and mechanisms are poorly understood. Here, the phytotoxic mechanisms of STE were investigated via the metabolomics of Amaranthus retroflexus L. A total of 140 and 113 differential metabolites were detected in the leaves and stems, respectively, among which amino acids, lipids, and phenolic compounds were significantly perturbed.

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Phytophthora nicotianae is an oomycete pathogen of global significance threatening many important crops. It is mainly controlled by chemosynthetic fungicides, which endangers ecosystem and human health; thus, there is an urgent need to explore alternatives for these fungicides. In this study, a new anti-oomycete aliphatic compound, 2,4decadienoic acid (DDA), was obtained through coculture of Bacillus subtilis Tpb55 and Trichoderma asperellum HG1.

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A new polyketide derivative, nafuredin C (), a novel heterocyclic dipeptide, trichodermamide G (), together with four known biogenetically related compounds nafuredin A (), trichodermamide A (), aspergillazin A (), and peniisocoumarin H (), were isolated from the mangrove-derived fungus D13. Their structures, including their absolute configurations, were determined by spectroscopic analysis and time-dependent density functional theory-electronic circular dichroism (ECD) calculations. Trichodermamide G was found to be a novel epithiodiketopiperazine derivative with an unprecedented cyclic system containing a sulfur bridge, and nafuredin C represented the third nafuredin derivative of these homologous compounds.

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Brevibacterium aureum DG-12, a new bacterial strain isolated from active sludge, was able to degrade and utilize cyfluthrin as a growth substrate in the mineral medium. Response surface methodology using central composite rotatable design of cultural conditions was successfully employed for optimization resulting in 88.6% degradation of cyfluthrin (50mgL(-1)) within 5days.

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The opportunistic pathogen Pseudomonas aeruginosa utilizes type III secretion system (T3SS) to translocate effector proteins into eukaryotic host cells that subvert normal host cell functions to the benefit of the pathogen, and results in serious infections. T3SS in P. aeruginosa is controlled by a complex system of regulatory mechanisms and signaling pathways.

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Pseudomonas aeruginosa can grow either as planktonic- or biofilm-form in response to environmental changes. Recent studies show that switching from biofilm to planktonic lifestyle requires rhamnolipids. Here we report the identification of a novel twocomponent system BqsS-BqsR that regulates biofilm decay in P.

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Human pathogen Pseudomonas aeruginosa uses quorum-sensing (QS) signalling systems to synchronize the production of virulence factors. There are two interrelated QS systems, las and rhl, in P. aeruginosa.

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The response regulator PprB and its cognate sensor PprA were recently reported as a two-component regulatory system that controls membrane permeability and antibiotic sensitivity of Pseudomonas aeruginosa. We found that a Tn5 insertion mutation in pprB caused a drastic reduction in virulence factor production and cell motility. A transcriptome analysis revealed that 175 genes were regulated by PprB.

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It is commonly known that bacteria may produce antibiotics to interfere with the normal biological functions of their competitors in order to gain competitive advantages. Here we report that Bacillus thuringiensis suppressed the quorum-sensing-dependent virulence of plant pathogen Erwinia carotovora through a new form of microbial antagonism, signal interference. E.

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