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1.
Front Microbiol ; 15: 1358752, 2024.
Article in English | MEDLINE | ID: mdl-38873147

ABSTRACT

Candida albicans (C. albicans), a microbe commonly isolated from Candida vaginitis patients with vaginal tract infections, transforms from yeast to hyphae and produces many toxins, adhesins, and invasins, as well as C. albicans biofilms resistant to antifungal antibiotic treatment. Effective agents against this pathogen are urgently needed. Antimicrobial peptides (AMPs) have been used to cure inflammation and infectious diseases. In this study, we isolated whole housefly larvae insect SVWC peptide 1 (WHIS1), a novel insect single von Willebrand factor C-domain protein (SVWC) peptide from whole housefly larvae. The expression pattern of WHIS1 showed a response to the stimulation of C. albicans. In contrast to other SVWC members, which function as antiviral peptides, interferon (IFN) analogs or pathogen recognition receptors (PRRs), which are the prokaryotically expressed MdWHIS1 protein, inhibit the growth of C. albicans. Eukaryotic heterologous expression of WHIS1 inhibited C. albicans invasion into A549 and HeLa cells. The heterologous expression of WHIS1 clearly inhibited hyphal formation both extracellularly and intracellularly. Furthermore, the mechanism of WHIS1 has demonstrated that it downregulates all key hyphal formation factors (ALS1, ALS3, ALS5, ECE1, HWP1, HGC1, EFG1, and ZAP1) both extracellularly and intracellularly. These data showed that heterologously expressed WHIS1 inhibits C. albicans invasion into epithelial cells by affecting hyphal formation and adhesion factor-related gene expression. These findings provide new potential drug candidates for treating C. albicans infection.

2.
Cardiol Rev ; 2024 May 30.
Article in English | MEDLINE | ID: mdl-38780252

ABSTRACT

Acute ST-segment elevation myocardial infarction (STEMI) is a formidable challenge in cardiovascular medicine, demanding advanced reperfusion strategies such as emergency percutaneous coronary intervention. While successful revascularization is pivotal, the persistent "no-reflow" phenomenon remains a clinical hurdle, often intertwined with microvascular dysfunction. Within this intricate scenario, the emergence of intramyocardial hemorrhage (IMH) has garnered attention as a significant contributor. This review offers a detailed exploration of the multifaceted relationship between IMH and the "no-reflow" phenomenon, delving into the mechanisms governing IMH occurrence, state-of-the-art diagnostic modalities, predictive factors, clinical implications, and the evolving landscape of preventive and therapeutic strategies. The nuanced examination aims to deepen our comprehension of IMH, providing a foundation for the identification of innovative therapeutic avenues and enhanced clinical outcomes for STEMI patients.

4.
J Ethnopharmacol ; 298: 115602, 2022 Nov 15.
Article in English | MEDLINE | ID: mdl-36030030

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: The fruit of Ginkgo biloba L. (Ginkgo nuts) has been used for a long time as a critical Chinese medicine material to treat cough and asthma, as well as a disinfectant. Similar records were written in the Compendium of Materia Medica (Ben Cao Gang Mu, pinyin in Chinese) and Sheng Nong's herbal classic (Shen Nong Ben Cao Jing, pinyin in Chinese). Recent research has shown that Ginkgo biloba exocarp extract (GBEE) has the functions of unblocking blood vessels and improving brain function, as well as antitumour activity and antibacterial activity. GBEE was shown to inhibit methicillin-resistant Staphylococcus aureus (MRSA) biofilm formation as a traditional Chinese herb in our previous report in this journal. AIM OF THE STUD: yThe antibiotic resistance of clinical bacteria has recently become increasingly serious. Thus, this study aimed to investigate the Ginkgo biloba exocarp extract (GBEE) antibacterial lineage, as well as its effect and mechanism on S. haemolyticus biofilms. This study will provide a new perspective on clinical multidrug resistant (MDR) treatment with ethnopharmacology herbs. METHODS: The microbroth dilution assay was carried out to measure the antibacterial effect of GBEE on 13 types of clinical bacteria. Bacterial growth curves with or without GBEE treatment were drawn at different time points. The potential targets of GBEE against S. haemolyticus were screened by transcriptome sequencing. The effects of GBEE on bacterial biofilm formation and mature biofilm disruption were determined by crystal violet staining and scanning electron microscopy. The metabolic activity of bacteria inside the biofilm was assessed by colony-forming unit (CFU) counting and (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2HY-tetrazolium bromide (MTT) assay. Quantitative polymerase chain reaction (qPCR) was used to measure the gene expression profile of GBEE on S. haemolyticus biofilm-related factors. RESULTS: The results showed that GBEE has bacteriostatic effects on 3 g-positive (G+) and 2 g-negative (G-) bacteria among 13 species of clinical bacteria. The antibacterial effect of GBEE supernatant liquid was stronger than the antibacterial effect of GBEE supernviaould-like liquid. GBEE supernatant liquid inhibited the growth of S. epidermidis, S. haemolyticus, and E. faecium at shallow concentrations with minimum inhibitory concentrations (MICs) of 2 µg/ml, 4 µg/ml and 8 µg/ml, respectively. Genes involved in quorum sensing, two-component systems, folate biosynthesis, and ATP-binding cassette (ABC) transporters were differentially expressed in GBEE-treated groups compared with controls. Crystal violet, scanning electron microscopy (SEM) and MTT assays showed that GBEE suppressed S. haemolyticus biofilm formation in a dose-dependent manner. Moreover, GBEE supernatant liquid downregulated cidA, cidB and atl, which are involved in cell lysis and extracellular DNA (eDNA) release, as well as downregulated the cbp, ebp and fbp participation in encoding cell-surface binding proteins. CONCLUSIONS: GBEE has an excellent antibacterial effect on gram-positive bacteria and also inhibits the growth of gram-negative bacteria, such as A. baumannii (carbapenem-resistant Acinetobacter baumannii) CRABA and S. maltophilia. GBEE inhibits the biofilm formation of S. haemolyticus by altering the regulation and biofilm material-related genes, including the release of eDNA and cell-surface binding proteins.


Subject(s)
Methicillin-Resistant Staphylococcus aureus , Staphylococcus haemolyticus , Anti-Bacterial Agents/pharmacology , Bacteria , Biofilms , Gentian Violet/pharmacology , Ginkgo biloba/chemistry , Microbial Sensitivity Tests , Plant Extracts/pharmacology
5.
Front Microbiol ; 13: 822148, 2022.
Article in English | MEDLINE | ID: mdl-35369527

ABSTRACT

Staphylococcus haemolyticus (S. haemolyticus) is the second most commonly isolated coagulase-negative staphylococcus (CoNS) in patients with hospital-acquired infections. It can produce phenol-soluble modulin (PSM) toxins and form biofilms. Compared with the wealth of information on Staphylococcus aureus and Staphylococcus epidermidis, very little is known about S. haemolyticus. There is an urgent need to find an effective preparation to combat the harm caused by S. haemolyticus infection. Chinese herbs have been utilized to cure inflammation and infectious diseases and have a long history of anticancer function in China. Here, we modified fusaric acid characterized from the metabolites of Gibberella intermedia, an endophyte previously isolated from Polygonum capitatum. This study shows that fusaric acid analogs (qy17 and qy20) have strong antibacterial activity against S. haemolyticus. In addition, crystal violet analyses and scanning electron microscopy observations demonstrated that qy17 inhibited biofilm formation and disrupted mature biofilms of S. haemolyticus in a dose-dependent manner. Additionally, it reduced the number of live bacteria inside the biofilm. Furthermore, the antibiofilm function of qy17 was achieved by downregulating transcription factors (sigB), transpeptidase genes (srtA), and bacterial surface proteins (ebp, fbp) and upregulating biofilm-related genes and the density-sensing system (agrB). To further elucidate the bacteriostatic mechanism, transcriptomic analysis was carried out. The following antibacterial mechanisms were uncovered: (i) the inhibition of heat shock (clpB, groES, groL, grpE, dnaK, dnaJ)-, oxidative stress (aphC)- and biotin response (bioB)-related gene expression, which resulted in S. haemolyticus being unable to compensate for various stress conditions, thereby affecting bacterial growth; and (ii) a reduction in the expression of PSM-beta (PSMß1, PSMß2, PSMß3) toxin- and Clp protease (clpP, clpX)-related genes. These findings could have major implications for the treatment of diseases caused by S. haemolyticus infections. Our research reveals for the first time that fusaric acid derivatives inhibit the expression of biofilm formation-related effector and virulence genes of S. haemolyticus. These findings provide new potential drug candidates for hospital-acquired infections caused by S. haemolyticus.

6.
Int J Biol Macromol ; 209(Pt A): 299-314, 2022 Jun 01.
Article in English | MEDLINE | ID: mdl-35381282

ABSTRACT

Antibiotic-resistant bacteria (including MRSA) in the clinic pose a growing threat to public health, and antimicrobial peptides (AMPs) have great potential as efficient treatment alternatives. Houseflies have evolved over long periods in complex, dirty environments, developing a special immune system to overcome challenges in harmful environments. AMPs are key innate immune molecules. Herein, two differentially expressed AMPs, Phormicins A and B, were identified by screening transcriptomic changes in response to microbial stimulation. Structural mimic assays indicated that these AMPs exhibited functional divergence due to their C-terminal features. Expression analysis showed that they had different expression patterns. Phormicin B had higher constitutive expression than Phormicin A. However, Phormicin B was sharply downregulated, whereas Phormicin A was highly upregulated, after microbial stimulation. The MIC, MBC and time-growth curves showed the antibacterial spectrum of these peptides. Crystal violet staining and SEM showed that Phormicin D inhibited MRSA biofilm formation. TEM suggested that Phormicin D disrupted the MRSA cell membrane. Furthermore, Phormicin D inhibited biofilm formation by downregulating the expression of biofilm-related genes, including altE and embp. Therefore, housefly Phormicins were functionally characterized as having differential expression patterns and antibacterial & antibiofilm activities. This study provides a new potential peptide for clinical MRSA therapy.


Subject(s)
Houseflies , Animals , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Antimicrobial Peptides , Biofilms , Houseflies/genetics , Microbial Sensitivity Tests
7.
Bioact Mater ; 6(12): 4729-4757, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34136723

ABSTRACT

Magnesium (Mg) and its alloys, as potential biodegradable materials, have drawn wide attention in the cardiovascular stent field because of their appropriate mechanical properties and biocompatibility. Nevertheless, the occurrence of thrombosis, inflammation, and restenosis of implanted Mg alloy stents caused by their poor corrosion resistance and insufficient endothelialization restrains their anticipated clinical applications. Numerous surface treatment tactics have mainly striven to modify the Mg alloy for inhibiting its degradation rate and enduing it with biological functionality. This review focuses on highlighting and summarizing the latest research progress in functionalized coatings on Mg alloys for cardiovascular stents over the last decade, regarding preparation strategies for metal oxide, metal hydroxide, inorganic nonmetallic, polymer, and their composite coatings; and the performance of these strategies in regulating degradation behavior and biofunction. Potential research direction is also concisely discussed to help guide biological functionalized strategies and inspire further innovations. It is hoped that this review can give assistance to the surface modification of cardiovascular Mg-based stents and promote future advancements in this emerging research field.

8.
Sci Rep ; 9(1): 12073, 2019 Aug 19.
Article in English | MEDLINE | ID: mdl-31427626

ABSTRACT

Compressive beamforming is a powerful approach for the direction-of-arrival (DOA) estimation and strength quantification of acoustic sources. The conventional grid-based discrete compressive beamformer suffers from the basis mismatch conundrum. Its result degrades under the situation that sources fall off the grid. The existing continuous compressive beamformer with linear or planar microphone arrays can circumvent the conundrum, but work well only for sources in a local region. Here we develop a panoramic continuous compressive beamformer with cuboid microphone arrays based on an atomic norm minimization (ANM) and a matrix pencil and paring method. To solve the positive semidefinite programming equivalent to the ANM efficiently, we formulate a solving algorithm based on the alternating direction method of multipliers. We also present an iterative reweighted ANM to enhance sparsity and resolution. The beamformer is capable of estimating the DOAs and quantifying the strengths of acoustic sources panoramically and accurately, whether a standard uniform or a sparse cuboid microphone array is utilized.

9.
Anim Sci J ; 90(3): 333-343, 2019 Mar.
Article in English | MEDLINE | ID: mdl-30628143

ABSTRACT

To explore the protein expression profiles of white yak (Bos grunniens) testis at different sexual developmental stages. The protein profiles of yak testis were determined using two-dimensional electrophoresis and the expression levels of 298 protein spots were analyzed. Mass spectrometry was performed to identify those significantly differential expressed proteins; Western blotting was used to confirm the results. During the developmental stages, 29 protein spots showed more than twofold differences (p < 0.05) at ≥1 time point and were successfully identified. Two proteins were upregulated with age (category 1), five proteins (17.2%) were downregulated with age (category 2), four proteins were upregulated before 4 years of age and downregulated thereafter (category 3), fifteen proteins were upregulated before 2 years of age and downregulated thereafter (category 4), and three proteins fluctuated with age (category 5). The expression patterns of regucalcin and heat shock 60 kDa protein in category 2 were confirmed. The 29 differentially expressed proteins from yak testes (some had more than one function) were categorized into binding (n = 15), catalytic activity (n = 13), molecular function regulator (n = 4), antioxidant (n = 4), molecular transducer (n = 2), transporter (n = 1), and structural molecule (n = 1). The identification and analysis of these testis proteins may assist in understanding the developmental biology of reproduction system in male yak.


Subject(s)
Proteins/genetics , Proteins/metabolism , Proteome/genetics , Proteome/metabolism , Sexual Maturation , Testis/growth & development , Testis/metabolism , Aging/genetics , Aging/metabolism , Animals , Blotting, Western , Cattle , Electrophoresis, Gel, Two-Dimensional , Gene Expression , Male , Mass Spectrometry , Reproduction , Testis/physiology
10.
J Vet Sci ; 16(3): 253-63, 2015.
Article in English | MEDLINE | ID: mdl-25549220

ABSTRACT

Cows infected with Escherichia (E.) coli usually experience severe clinical symptoms, including damage to mammary tissues, reduced milk yield, and altered milk composition. In order to investigate the host response to E. coli infection and discover novel markers for mastitis treatment, mammary tissue samples were collected from healthy cows and bovines with naturally occurring severe E. coli mastitis. Changes of mammary tissue proteins were examined using two-dimensional gel electrophoresis and label-free proteomic approaches. A total of 95 differentially expressed proteins were identified. Of these, 56 proteins were categorized according to molecular function, cellular component, and biological processes. The most frequent biological processes influenced by the proteins were response to stress, transport, and establishment of localization. Furthermore, a network analysis of the proteins with altered expression in mammary tissues demonstrated that these factors are predominantly involved with binding and structural molecule activities. Vimentin and a-enolase were central "functional hubs" in the network. Based on results from the present study, disease-induced alterations of protein expression in mammary glands and potential markers for the effective treatment of E. coli mastitis were identified. These data have also helped elucidate defense mechanisms that protect the mammary glands and promote the pathogenesis of E. coli mastitis.


Subject(s)
Escherichia coli Infections/veterinary , Escherichia coli/physiology , Mammary Glands, Animal/immunology , Mastitis, Bovine/genetics , Proteome/genetics , Proteomics , Animals , Cattle , Electrophoresis, Gel, Two-Dimensional/veterinary , Escherichia coli Infections/genetics , Escherichia coli Infections/immunology , Escherichia coli Infections/microbiology , Female , Mammary Glands, Animal/pathology , Mastitis, Bovine/immunology , Mastitis, Bovine/microbiology , Proteome/metabolism
11.
J Org Chem ; 79(21): 10696-702, 2014 Nov 07.
Article in English | MEDLINE | ID: mdl-25279967

ABSTRACT

We used aryl bromides as inexpensive starting materials to enantioselectively arylate aldehydes in one pot. Aryl bromides readily transfer aryls to aryllithiums with n-butyllithium, successively to triarylaluminums with aluminum chloride, and then to aryltitaniums with titanium isopropoxide. Finally aryltitaniums arylate aldehydes catalyzed by (S)-H8-BINOL-Ti(Oi-Pr)2 in excellent yields and enantioselectivities. The additive TMEDA evidently suppresses the racemic background reaction promoted by LiCl generated from salt metathesis. This procedure represents a cost-effective and operationally convenient method for enantioenriched diarylmethanols.


Subject(s)
Aldehydes/chemistry , Coordination Complexes/chemistry , Hydrocarbons, Chlorinated/chemistry , Organometallic Compounds/chemistry , Catalysis , Molecular Structure , Stereoisomerism
12.
J Org Chem ; 78(7): 3243-9, 2013 Apr 05.
Article in English | MEDLINE | ID: mdl-23464705

ABSTRACT

In the addition of TMEDA in toluene, aryl Grignards could effectively and site-specifically ortho-arylate electron-deficient heteroarenes under mild conditions. This endeavor successfully changed the old low-yielding reaction, aryl Grignard addition to N-heteroarenes, into an efficient procedure for heterobiaryls. The combination of the inexpensive aryl Grignards, TMEDA, the cost-free air, no use of any transition-metal catalyst, the mild reaction conditions, and the high-yielding gram-scale results enables this new procedure to be cost-effective and potentially utilizable in industry.


Subject(s)
Ethylenediamines/chemistry , Heterocyclic Compounds/chemistry , Organometallic Compounds/chemistry , Pyridines/chemistry , Quinolines/chemistry , Quinoxalines/chemical synthesis , Electrons , Molecular Structure , Quinoxalines/chemistry , Toluene/chemistry
14.
Vet Res Commun ; 33(4): 295-303, 2009 Apr.
Article in English | MEDLINE | ID: mdl-18814050

ABSTRACT

To investigate the disease-related proteins and understand molecular mechanism of mastitis at the protein level, this project presents the protein changes in the mammary gland between healthy cows and clinical mastitic cows using two-dimensional gel electrophoresis (2-DE), after stained with colloidal Coomassie Bright Blue, six spots of differentially expressed protein were detected by PDQuest software and subjected to ion trap mass spectrometer equipped with a HPLC system, and five proteins were identified. Hemoglobin beta, kappa-casein and tryptophanyl-tRNA-synthetase (TrpRS) in healthy dairy cows, while hemoglobin beta, cytochrome C oxidase and annexin V in clinical mastitic cows were identified, they were involved in binding, transport and catalytic activity. The results may provide valuable information for the investigating of the host mammary immune system response to defense against pathogens at the protein level and potential protein targets for treatment.


Subject(s)
Cattle/metabolism , Mastitis, Bovine/metabolism , Proteomics/methods , Animals , Annexin A5/analysis , Caseins/analysis , Cattle/blood , Chromatography, High Pressure Liquid , Electron Transport Complex IV/analysis , Electrophoresis, Gel, Two-Dimensional/veterinary , Female , Hemoglobins/analysis , Mastitis, Bovine/blood , Mastitis, Bovine/enzymology , Tandem Mass Spectrometry/veterinary , Tryptophan-tRNA Ligase/analysis
15.
Agric Sci China ; 8(10): 1263-1269, 2009 Oct.
Article in English | MEDLINE | ID: mdl-32288750

ABSTRACT

The current research presents the protein changes in plasma from healthy dairy cows and clinical mastitic cows using two-dimensional gel electrophoresis (2-DE). After staining with silver nitrate and Coomassie Blue, differential expression proteins were detected by PDQuest 7.4 software, and then subjected to ion trap mass spectrometer equipped with a Surveyor HPLC System, differential spots of protein were identified. Three protein spots that originated from preparation gels were identified to be two proteins. Overall, haptoglobin precursor was up-regulated in cows infected with clinical mastitis and could be a mastitis-associated diagnostic marker, whereas SCGB 2A1 (secretoglobin, family 2A, member 1) was down-regulated protein. Plasma protein expression patterns were changed when cows were infected with mammary gland inflammation; it suggests that analysis of differential expression protein might be useful to clarify the mechanisms involved in the pathophysiology, and find new diagnostic markers of mastitis and potential protein targets for treatment.

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