Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 24
Filter
Add more filters










Publication year range
1.
Food Res Int ; 184: 114262, 2024 May.
Article in English | MEDLINE | ID: mdl-38609241

ABSTRACT

There are complex and diverse substances in traditional vinegars, some of which have been identified as biologically active factors, but the variety of functional compounds is currently restricted. In this study, it was aimed to determine the bioactive compounds in 10 typical functional vinegars. The findings shown that total flavonoids (0.21-7.19 mg rutin equivalent/mL), total phenolics (0.36-3.20 mg gallic acid equivalent/mL), and antioxidant activities (DPPH: 3.17-47.63 mmol trolox equivalent/L, ABTS: 6.85-178.29 mmol trolox equivalent/L) varied among different functional vinegars. In addition, the concentrations of the polysaccharides (1.17-44.87 mg glucose equivalent/mL) and total saponins (0.67-12.46 mg oleanic acid equivalent/mL) were determined, which might play key role for the function of tested vinegars. A total of 8 organic acids, 7 polyphenol compounds and 124 volatile compounds were measured and tentatively identified. The protocatechuic acid (4.81-485.72 mg/L), chlorogenic acid (2.69-7.52 mg/L), and epicatechin (1.18-97.42 mg/L) were important polyphenol compounds in the functional vinegars. Redundancy analysis indicated that tartaric acid, oxalic acid and chlorogenic acid were significantly positively correlated with antioxidant capacity. Various physiologically active ingredients including cyclo (Pro-Leu), cyclo (Phe-Pro), cyclo (Phe-Val), cyclo (Pro-Val), 1-monopalmitin and 1-eicosanol were firstly detected in functional vinegars. Principle component analysis revealed that volatiles profile of bergamot Monascus aromatic vinegar and Hengshun honey vinegar exhibited distinctive differences from other eight vinegar samples. Moreover, the partial least squares regression analysis demonstrated that 11 volatile compounds were positively correlated with the antioxidant activity of vinegars, which suggested these compounds might be important functional substances in tested vinegars. This study explored several new functionally active compounds in different functional vinegars, which could widen the knowledge of bioactive factor in vinegars and provide new ideas for further development of functional vinegar beverages.


Subject(s)
Acetic Acid , Antioxidants , Chlorogenic Acid , Gallic Acid , Polyphenols
2.
Front Cell Infect Microbiol ; 13: 1194133, 2023.
Article in English | MEDLINE | ID: mdl-37829609

ABSTRACT

This study aimed to explore the epidemic, clinical characteristics, and molecular and virulence attributes of Klebsiella pneumoniae serotype K54 (K54-Kp). A retrospective study was conducted on 328 strains of Klebsiella pneumoniae screened in a Chinese hospital from January 2016 to December 2019. The virulence genes and antibiotic resistance genes (ARGs) were detected by PCR, and a drug sensitivity test was adopted to detect drug resistance. Multilocus sequence typing (MLST) and PFGE were performed to determine the clonal correlation between isolates. Biofilm formation assay, serum complement-mediated killing, and Galleria mellonella infection were used to characterize the virulence potential. Our results showed that thirty strains of K54-Kp were screened from 328 strains of bacteria, with an annual detection rate of 2.29%. K54-Kp had a high resistance rate to antibiotics commonly used in the clinic, and patients with hepatobiliary diseases were prone to K54-Kp infection. MLST typing showed 10 sequence typing, mainly ST29 (11/30), which concentrated in the B2 cluster. K54-Kp primarily carried virulence genes of aerobactin, silS, allS, wcaG, wabG, and mrkD, among which the terW gene was closely related to ST29 (p<0.05). The strains infected by the bloodstream had strong biofilm formation ability (p<0.05). Most strains were sensitive to serum. Still, the virulence of pLVPK-like virulence plasmid in ST29-K54 Klebsiella pneumoniae was lower than that of ST11 type and NTUH-K2044 in the Galleria mellonella model. Therefore, these findings supply a foundation to roundly comprehend K54-Kp, and clinicians should strengthen supervision and attention.


Subject(s)
Klebsiella Infections , Moths , Animals , Humans , Virulence/genetics , Klebsiella pneumoniae , Multilocus Sequence Typing , Retrospective Studies , Phenotype , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Plasmids/genetics , Klebsiella Infections/microbiology
3.
Front Microbiol ; 14: 1277320, 2023.
Article in English | MEDLINE | ID: mdl-37840706

ABSTRACT

Background: Colistin has emerged as a last-resort therapeutic against antibiotic-resistant bacterial infections, particularly those attributed to carbapenem-resistant Enterobacteriaceae (CRE) like CRKP. Yet, alarmingly, approximately 45% of multidrug-resistant Klebsiella pneumoniae strains now manifest resistance to colistin. Through our study, we discerned that the synergy between carbapenemase and IS elements amplifies resistance in Klebsiella pneumoniae, thereby narrowing the existing therapeutic avenues. This underscores the instrumental role of IS elements in enhancing colistin resistance through mgrB disruption. Methods: From 2021 to 2023, 127 colistin-resistant Klebsiella pneumoniae isolates underwent meticulous examination. We embarked on an exhaustive genetic probe, targeting genes associated with both plasmid-mediated mobile resistance-encompassing blaKPC, blaNDM, blaIMP, blaVIM, blaOXA-48-like, and mcr-1 to mcr-8-and chromosome-mediated resistance systems, including PhoP/Q, PmrA/B, and mgrB. PCR amplification revealed the presence of virulence-associated genes from the pLVPK plasmid, such as rmpA, rmpA2, iucA, iroB, and peg344. mgrB sequencing was delegated to Sangon Biotech, Shanghai, and the sequences procured were validated using BLAST. Our search for IS elements was navigated through the IS finder portal. Phenotypically, we harnessed broth microdilution (BMD) to ascertain the MICs of colistin. To sketch the clonal lineage of mgrB-mutated CoR-Kp isolates, sophisticated methodologies like MLST and PFGE were deployed. S1-PFGE unraveled the intrinsic plasmids in these isolates. Our battery of virulence assessment techniques ranged from the string test and capsular serotyping to the serum killing assay and the Galleria mellonella larval infection model. Results: Among the 127 analyzed isolates, 20 showed an enlarged mgrB PCR amplicon compared to wild-type strains. These emerged over a three-year period: three in 2021, thirteen in 2022, and four in 2023. Antimicrobial susceptibility tests revealed that these isolates consistently resisted several drugs, notably TCC, TZP, CAZ, and COL. Additionally, 85% resisted both DOX and TOB. The MICs for colistin across these strains ranged between 16 to 64 mg/L, with a median of 40 mg/L. From a genetic perspective, MLST unanimously categorized these mgrB-mutated CoR-hvKp isolates as ST11. PFGE further delineated them into six distinct clusters, with clusters A and D being predominant. This distribution suggests potential horizontal and clonal genetic transmission. Intriguingly, every mgrB-mutated CoR-hvKP isolate possessed at least two virulence genes akin to the pLVPK-like virulence plasmid, with iroB and rmpA2 standing out. Their virulence was empirically validated both in vitro and in vivo. A pivotal discovery was the identification of three distinct insertion sequence (IS) elements within or near the mgrB gene. These were:ISKpn26 in eleven isolates, mainly in cluster A, with various insertion sites including +74, +125, and an upstream -35.ISKpn14 in four isolates with insertions at +93, -35, and two upstream at -60.IS903B present in five isolates, marking positions like +74, +125, +116, and -35 in the promoter region. These diverse insertions, spanning six unique locations in or near the mgrB gene, underscore its remarkable adaptability. Conclusion: Our exploration spotlights the ISKpn element's paramount role in fostering mgrB gene mutations in ST11 hypervirulent colistin-resistant Klebsiella pneumoniae. Employing MLST and PFGE, we unearthed two primary genetic conduits: clonal and horizontal. A striking observation was the ubiquitous presence of the KPC carbapenemase gene in all the evaluated ST11 hypervirulent colistin-resistant Klebsiella pneumoniae strains, with a majority also harboring the NDM gene. The myriad mgrB gene insertion locales accentuate its flexibility and the overarching influence of IS elements, notably the pervasive IS5-like variants ISKpn26 and IS903B. Our revelations illuminate the escalating role of IS elements in antibiotic resistance within ST11 hypervirulent colistin-resistant Klebsiella pneumoniae, advocating for innovative interventions to counteract these burgeoning resistance paradigms given their profound ramifications for prevailing treatment modalities.

4.
Chinese Journal of School Health ; (12): 1080-1083, 2023.
Article in Chinese | WPRIM (Western Pacific) | ID: wpr-985420

ABSTRACT

Objective@#To understand the correlation between depression, sleep quality and dental caries among college students in Chongqing, so as so provide reference basis for targeted health education.@*Methods@#From January to June 2022, a multi stage sampling method was used to select 627 students from six colleges in Chongqing. According to the Fourth National Epidemiological Survey of Oral Health and World Health Organization standards, dental caries were examined and diagnosed. The Self Rating Depression Scale (SDS), Pittsburgh Sleep Quality Index (PSQI) Questionnaire and general situation questionnaire were adopted to investigate depressive symptoms and sleep quality of college students. Correlation analysis was performed to study the correlation between depression, sleep quality and dental caries.@*Results@#The prevalence of dental caries among college students was 42.1%, and there was a statistically significant difference in dental caries prevalence among college students depending on their gender, major, body shape, parental education level, and family sources ( χ 2=14.49, 16.81, 7.82, 15.14, 7.34, P <0.05). The prevalence of depressive symptoms was 13.9%, and there was a statistically significant difference in SDS scores and depression prevalence among students of different body types ( χ 2=10.99, P <0.05). The PSQI score was (4.36±0.94) points, and the rate of poor sleep quality was 26.16%. Furthermore, there was a statistically significant difference in the PSQI score and rate of poor sleep quality among college students of different genders and body types ( χ 2=25.41, 17.59, P <0.05). There was a certain correlation between the occurrence of dental caries and poor sleep quality and depressive symptoms among college students, with contingency coefficients of 0.15 and 0.13, respectively ( P <0.05).@*Conclusion@#The prevalence of dental caries is high among college students in Chongqing. The occurrence of dental caries may be related to depression and sleep quality.

5.
Article in English | MEDLINE | ID: mdl-36212946

ABSTRACT

The PVF Tedlar is widely used for gas collection in clinical diagnostics and environmental research. However, sample collection is frequently associated with the degradation, adsorption, or transformation of sensitive chemicals. Here, we explore to what extent the Tedlar bag collection effects the composition of expired breath samples. Collected breath samples were analyzed using the EESI-MS technique after the storage time of 30 min, 1 h, 2 h, 3 h, 4 h, 5 h, and 6 h, respectively. Our results demonstrated the gradual MS signal decay after 3 h storage. The decay rate of 3 h is about 45% and 6 h is about 88%. Therefore, the Tedlar bag is suggested as a reliable breath holder on the time scale of <3 h.

6.
Molecules ; 27(5)2022 Feb 27.
Article in English | MEDLINE | ID: mdl-35268682

ABSTRACT

Trametes hirsuta is able to secrete laccase isoenzymes including constitutive and inducible forms, and has potential application for bioremediation of environmental pollutants. Here, an inducible group B laccase from T. hirsuta MX2 was heterologously expressed in Pichia pastoris, and its yield reached 2.59 U/mL after 5 days of methanol inducing culture. The optimal pH and temperature of recombinant laccase (rLac1) to 2,2'-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) were 2.5 and 60 °C, respectively. Metal ions showed different effect on rLac1 which Mg2+, Cu2+, and K+ increased enzyme activity as their concentration increased, whereas Zn2+, Na+, and Fe2+ inhibited enzyme activity as their concentration increased. rLac1 showed good tolerance to organic solvents, and more than 42% of its initial activity remained in 10% organic solvents. Additionally, rLac1 exhibited a more efficient decolorization ability for remazol brilliant blue R (RBBR) than for acid red 1 (AR1), crystal violet (CV), and neutral red (NR). Molecular docking results showed RBBR has a stronger binding affinity with laccase than other dyes by interacting with substrate binding cavity of enzyme. The results indicated rLac1 may be a potential candidate for dye removal from textile wastewater.


Subject(s)
Laccase
7.
Mol Med ; 27(1): 97, 2021 09 03.
Article in English | MEDLINE | ID: mdl-34479474

ABSTRACT

BACKGROUND/AIM: N-Acetylcysteine (NAC) demonstrates applications in the prevention of exacerbation of chronic obstructive pulmonary disease (COPD). COPD is often characterized by fibrosis of the small airways. This study aims at investigating the physiological mechanisms by which NAC might mediate the pulmonary fibrosis in COPD. METHODS: A total of 10 non-smokers without COPD and 10 smokers with COPD were recruited in this study, and COPD rat models were established. Cigarette smoke extract (CSE) cell models were constructed. The gain- or loss-of-function experiments were adopted to determine the expression of VWF and the extent of p38 MAPK phosphorylation, levels of interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), and immunoglobulins (IgG, IgM and IgA) in the serum of COPD rats and supernatant of alveolar epithelial cells and to detect cell invasion and migration and the ratio of CD3+, CD4+, CD8+ and CD4+/CD8+T lymphocytes. RESULTS: Expression of VWF and the extent of p38 MAPK phosphorylation were increased in COPD. NAC inhibited p38 MAPK phosphorylation by reducing the VWF expression. NAC could inhibit cell migration and invasion, elevate E-cadherin expression, the ratio of CD3+, CD4+, CD8+ and CD4+/CD8+T lymphocytes, and levels of IgG, IgA, and IgM, and reduce N-cadherin expression and levels of IL-6 and TNF-α in CSE cells and serum of COPD rats. NAC promoted immune response and suppressed epithelial-mesenchymal transformation (EMT) to relieve COPD-induced pulmonary fibrosis in vitro and in vivo by inhibiting the VWF/p38 MAPK axis. CONCLUSIONS: Collectively, NAC could ameliorate COPD-induced pulmonary fibrosis by promoting immune response and inhibiting EMT process via the VWF/p38 MAPK axis, therefore providing us with a potential therapeutic target for treating COPD.


Subject(s)
Antioxidants/pharmacology , Epithelial-Mesenchymal Transition/drug effects , Immunomodulation/drug effects , Pulmonary Disease, Chronic Obstructive/etiology , Pulmonary Disease, Chronic Obstructive/metabolism , p38 Mitogen-Activated Protein Kinases/metabolism , von Willebrand Factor/metabolism , Biomarkers , Disease Susceptibility , Humans , Pulmonary Disease, Chronic Obstructive/diagnosis , Signal Transduction
8.
Dalton Trans ; 50(32): 11137-11146, 2021 Aug 28.
Article in English | MEDLINE | ID: mdl-34324621

ABSTRACT

Zn2Ti3O8/g-C3N4 (0, 1, 3 and 8 wt%) composites were prepared via a simple solvothermal method, and their physical and electrochemical properties were systematically analyzed. SEM and HRTEM results show that the Zn2Ti3O8/g-C3N4 spherical structures with width sizes of about 500-700 nm are plump and uniform. Moreover, g-C3N4 with a large specific surface area can effectively buffer the deformation of Zn2Ti3O8 and reduce the resistance of Zn2Ti3O8 charge transfer and Li+ diffusion, thus improving the conductivity of Zn2Ti3O8. The results reveal that Zn2Ti3O8/g-C3N4 (3 wt%) had the most outstanding electrochemical performance of all samples. It can deliver discharge (charge) capacities of 444.6 (387.9), 284.5 (280.8), 197.5 (199.9), 149.9 (149.3), 119.2 (118.7) and 81.4 (81) mA h g-1 cycled at 50, 100, 300, 600, 900, and 1500 mA g-1, respectively. At the same current densities, pure Zn2Ti3O8 only provides discharge (charge) capacities of 325.4 (283.5), 223.7 (219.5), 142.9 (141.8), 95.4(94.8), 69.4 (69.4) and 38.3 (39.3) mA h g-1. The results verify that Zn2Ti3O8/g-C3N4 materials are expected to be remarkable anode materials for Li-ion batteries.

9.
Oncol Rep ; 44(3): 1184-1193, 2020 09.
Article in English | MEDLINE | ID: mdl-32705224

ABSTRACT

Lung cancer is the leading cause of cancer­associated mortality worldwide. Parthenolide (PTL), a natural product extracted from the plant Tanacetum parthenium, (a flowering plant in the daisy family, Asteraceae) has been reported to inhibit cancer cell growth, including that of human lung cancer. However, the underlying mechanisms by which PTL exerts its anticancer effect have remained to be fully elucidated. In the present study, Cell Counting Kit­8 and colony formation assays were used to assess the effect of PTL to inhibit cell proliferation, a wound­healing assay was performed to assess cell migration and western blot analysis and PCR were employed to reveal the molecular mechanisms by which PTL inhibits human lung carcinoma cell growth. The results indicated that PTL substantially inhibited cell proliferation and migration in two lung cancer cell lines A549 and H1299. Mechanistically, the phosphorylation of insulin­like growth factor 1 receptor (IGF­1R), Akt and forkhead box O3α (FoxO3α) was blocked by PTL. Furthermore, IGF­1­induced Akt [protein kinase B or (PKB)] and FoxO3α phosphorylation were also inhibited by PTL treatment. In addition, PTL significantly suppressed lung cancer growth in a subcutaneous xenograft mouse model. Taken together, the present in vivo and in vitro results indicate that PTL may suppress lung cancer growth through inhibiting IGF­1R­mediated PI3K/Akt/FoxO3α signaling, suggesting that PTL may be an attractive candidate for the treatment of lung cancer.


Subject(s)
Lung Neoplasms/drug therapy , Sesquiterpenes/pharmacology , Animals , Cell Line, Tumor , Cell Movement/drug effects , Cell Proliferation/drug effects , Forkhead Box Protein O3/metabolism , Humans , Insulin-Like Growth Factor I/metabolism , Lung Neoplasms/pathology , Male , Mice , Phosphatidylinositol 3-Kinases/metabolism , Phosphorylation/drug effects , Proto-Oncogene Proteins c-akt/metabolism , Receptor, IGF Type 1/metabolism , Sesquiterpenes/therapeutic use , Signal Transduction/drug effects , Xenograft Model Antitumor Assays
10.
Int J Biol Macromol ; 153: 892-901, 2020 Jun 15.
Article in English | MEDLINE | ID: mdl-32142843

ABSTRACT

A composite film composed of whey protein isolate (WPI) and psyllium seed gum (PSG) was investigated. Its physicochemical, mechanical and structural properties were determined at different ratios of WPI/PSG (1:0, 3:1, 1:1, 1:3, 0:1). WPI/PSG composite films had higher water contact angle and water vapor permeability, as well as lower oxygen permeability and light transmittance as compared with single WPI or PSG films. With the increase in PSG concentration, higher film brightness and whiteness index, and smaller total color difference were observed. The tensile strength and elastic modulus of the composite film at WPI/PSG ratio of 1:1 was the highest. Elongation at break of composite films was higher than that of the single films. WPI/PSG composite films were more effective than single films in reducing the surface cracks and degree of cracks. XRD revealed a typical semi-crystalline amorphous structure of the composite films. With the increase of the PSG content, higher diffraction peak strength and crystallinity of the films were observed. The results indicated that the properties of the WPI/PSG composite film were superior to that of PSG or WPI film alone. The composite film at WPI/PSG ratio of 1:1 resulted in the highest comprehensive physicochemical and mechanical performance.


Subject(s)
Chemical Phenomena , Edible Films , Mechanical Phenomena , Plant Gums/chemistry , Psyllium/chemistry , Seeds/chemistry , Whey Proteins/chemistry , Hydrophobic and Hydrophilic Interactions , Oxygen/chemistry , Permeability , Solubility , Water/chemistry
11.
Polymers (Basel) ; 12(2)2020 Feb 14.
Article in English | MEDLINE | ID: mdl-32074987

ABSTRACT

In this present study, the thermodynamic and thermal properties of glycerol and nisin-incorporated gum ghatti (GG, Anogeissus latifolia)-based films were determined. The films exhibited type III isotherm behaviors. Moisture content (MC) of films was increased with increasing water activity (aw) and decreased with higher temperature. The incorporation of glycerol and nisin increased the sorption ability of GG films. The net isosteric heat of adsorption (qst) and differential entropy (Sd) were decreased with increasing MC, showing an exponential negative correlation between them. Spreading pressure (φ) was increased with increasing aw, but decreased with higher temperature. This incorporation of glycerol and nisin increased the qst, Sd and φ of the GG films. The sorption behaviors were enthalpy-driven and non-spontaneous processes. The glass transition temperature (Tg), critical MC and aw of the films were decreased, and increased respectively with the incorporation of glycerol and nisin. This work provides a theoretical basis for the application of edible films in fresh food preservation.

12.
Fish Physiol Biochem ; 46(1): 383-394, 2020 Feb.
Article in English | MEDLINE | ID: mdl-31782040

ABSTRACT

In this study, the mechanism that VC inhibits lipid deposition through GSK-3ß/mTOR signaling was investigated in the liver of Danio rerio. The results indicated that 0.5- and 1.0-g/kg VC treatments activated mTOR signaling by inhibiting GSK-3ß expression. The mRNA expression of FAS, ACC, and ACL, as well as the content of TG, TC, and NEFA, was decreased by 0.5- and 1.0-g/kg VC treatments. Moreover, to confirm GSK-3ß playing a key role in regulating TSC2 and mTOR, GSK-3ß RNA was interfered and the activity of GSK-3ß was inhibited by 25- and 50-mg/L LiCl treatments, respectively. The results indicated that GSK-3ß inactivation played a significant role in inducing mTOR signaling and inhibiting lipid deposition. VC treatments could induce mTOR signaling by inhibiting GSK-3ß, and mTOR further participated in regulating lipid deposition by controlling lipid profile in the liver of zebrafish.


Subject(s)
Ascorbic Acid , Glycogen Synthase Kinase 3 beta/metabolism , TOR Serine-Threonine Kinases/metabolism , Zebrafish Proteins/metabolism , Zebrafish/physiology , Animals , Lipid Metabolism , Lipids , Liver , Signal Transduction , beta Catenin
13.
Mol Biol Rep ; 47(1): 477-488, 2020 Jan.
Article in English | MEDLINE | ID: mdl-31664595

ABSTRACT

In this study, two laccase isoenzymes (Lac1 and Lac2) from the culture supernatant of Trametes hirsuta MX2 were purified, and the genes (Lac1 and Lac2) coding the isoenzymes were cloned. Both Lac1 and Lac2 contained an open reading frame of 1563 bp with an identity of 79%. The two isoenzymes showed significant biochemical differences. The maximal activities of Lac1 and Lac2 were at pH 2.5 with 2-2'-azino-di-(3-ethylbenzthiazoline sulfonic acid) (ABTS), and the optimal temperatures for the activities of Lac1 and Lac2 were 60 and 50 °C, respectively. Lac1 exhibited excellent resistance to acidic conditions and retained 62.17% of its initial activity at pH 2.5 after a 72-h incubation. Lac2 was more thermostable than Lac1 with half-lives (t1/2) of 9.58 and 3.12 h at 50 and 60 °C, respectively; the t1/2 of Lac1 were only 4.19 and 0.88 h, respectively. Both Lac1 and Lac2 isoenzymes have a strong tolerance to Mg2+, Mn2+, Cu2+, and EDTA (50 mM). At a low concentration of 0.05 U mL-1, the enzymes could decolorize towards Remazol Brilliant Blue R, Acid Red 1, Crystal Violet, and Neutral Red in the presence of ABTS. These unusual properties demonstrated that the two laccases have strong potential for specific industrial applications.


Subject(s)
Coloring Agents , Fungal Proteins , Laccase , Trametes , Cloning, Molecular , Coloring Agents/analysis , Coloring Agents/chemistry , Coloring Agents/metabolism , Enzyme Stability , Fungal Proteins/chemistry , Fungal Proteins/genetics , Fungal Proteins/isolation & purification , Fungal Proteins/metabolism , Hydrogen-Ion Concentration , Isoenzymes , Laccase/chemistry , Laccase/genetics , Laccase/isolation & purification , Laccase/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Trametes/enzymology , Trametes/genetics
14.
BMC Genomics ; 20(1): 480, 2019 Jun 11.
Article in English | MEDLINE | ID: mdl-31185888

ABSTRACT

BACKGROUND: Plasmids play an vital role in driving the rapid global spread of antimicrobial resistance and adaptation to changing ambient conditions. It has been suggested that the presence of plasmids can pose tremendous impacts on the host physiology. However, little is known regarding the contributions of carbapenemase-encoding plasmid carriage on the physiology and pathogenicity of hypervirulent K. pneumoniae (hvKP). RESULTS: Here we performed a transcriptomic analysis of hvKP with or without carbapenemase-encoding plasmid p24835-NDM5. The results had shown 683 genes with differential expression (false discovery rate, ≤0.001; > 2-fold change), of which 107 were up-regulated and 576 were down-regulated. Gene groups with functions relating to carbohydrate metabolism and multidrug efflux system were increased in genes with increased expression, and those relating to capsule biosynthesis and virulence factors were increased in the genes with decreased expression. In agreement with these changes, survival rate of TfpNDM-hvKP in the presence of normal human serum decreased, and competitive index (CI values) indicated significant fitness defects in the plasmid-carrying hvKP strain when co-cultured with its plasmid-free isogenic ancestor and the ATCC control. Moreover, the p24835-NDM5-containing hvKP strain retained its high neutrophil-mediated phagocytosis and murine lethality. CONCLUSION: These data indicate that hvKP responds to carbapenemase-encoding plasmid by altering the expression of genes involved in carbohydrate metabolism, antibiotic resistance, capsule biosynthesis and virulence expression. Apart from antibiotic resistance selective advantages, carbapenemase-encoding plasmid carriage may also lead to virulence change or adaption to specific habitats in hvKP strain.


Subject(s)
Bacterial Proteins/genetics , Gene Expression Profiling , Klebsiella pneumoniae/genetics , Phenotype , Plasmids/genetics , beta-Lactamases/genetics , Adult , Animals , Anti-Bacterial Agents/pharmacology , Biofilms/growth & development , Carbohydrate Metabolism/genetics , Humans , Kinetics , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/metabolism , Klebsiella pneumoniae/pathogenicity , Mice , Neutrophils/drug effects , Neutrophils/immunology , Phagocytosis , Virulence
15.
J Sci Food Agric ; 99(10): 4781-4792, 2019 Aug 15.
Article in English | MEDLINE | ID: mdl-30953363

ABSTRACT

BACKGROUND: Drying efficiency and quality maintenance are the major concerns of both manufactures and consumers. Heat pump drying (HPD) is suitable for heat sensitive foodstuffs due to its ability to independently control the drying operation parameters. However, lower drying rate and energy efficiency in the later period of HPD are the bottlenecks that restrain its application. A novel approach using hydrocolloids as pretreatment coatings prior to drying was designed to solve these problems. The effects of sodium alginate (SA) coating, drying temperatures and air velocities on the drying characteristics and quality attributes of scallop adductors were evaluated. RESULTS: Drying took place in the falling rate period. Drying time decreased with increasing temperature, air velocity and SA coating. The Two Term model and the Wang and Singh model gained the best fit for thin-layer drying of scallop adductors and SA film, respectively. Effective moisture diffusivity increased with temperature, velocity and SA coating and were in the range 7.352-14.620 × 10-11 , 9.890-17.100 × 10-11 and 2.348-4.604 × 10-10  m2  s-1 for uncoated scallop adductors, SA coated scallop adductors and SA films, respectively. The activation energies for SA films, coated and uncoated scallop adductors were 17.07, 20.78 and 26.17 kJ mol-1 , respectively. Dried scallop adductors with SA coating pretreatment exhibited a significant lower value of shrinkage rate and hardness, and higher value of toughness than uncoated ones at 30 °C and 2.0 m s-1 (P < 0.05). CONCLUSION: Hydrocolloid coating is a promising pretreatment in improving HPD efficiency and enhancing quality attributes of dried scallop adductors. © 2019 Society of Chemical Industry.


Subject(s)
Alginates/analysis , Food Preservation/methods , Food Preservatives/analysis , Pectinidae/chemistry , Animals , Color , Desiccation , Food Preservation/instrumentation , Hardness , Hot Temperature
16.
Oxid Med Cell Longev ; 2015: 703709, 2015.
Article in English | MEDLINE | ID: mdl-26185593

ABSTRACT

Acrylamide (ACR) has been classified as a neurotoxic agent in animals and humans. Melatonin (MT) has been shown to be potentially effective in preventing oxidative stress related neurodegenerative disorders. In this study, whether MT exerted a protective effect against ACR-induced oxidative damage was investigated. Results in cells showed that reactive oxygen species (ROS) and malondialdehyde (MDA) significantly increased after ACR treatment for 24 h. MT preconditioning or cotreatment with ACR reduced ROS and MDA products, whereas the inhibitory effect of MT on oxidant generation was attenuated by blocking the MT receptor. Increased DNA fragmentation caused by ACR was significantly decreased by MT coadministration. In vivo, rats at 40 mg/kg/day ACR by gavage for 12 days showed weight loss and gait abnormality, Purkinje cell nuclear condensation, and DNA damage in rat cerebellum. MT (i.p) cotreatment with ACR not only recovered weight and gait of rats, but also decreased nuclear condensation and DNA damage in rat cerebellum. Using MDA generation, glutathione (GSH) level, superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) activities in rat cerebellum as indicators, MT alleviated ACR-induced lipid peroxidation and depressed antioxidant capacity. Our results suggest that MT effectively prevents oxidative damage induced by ACR.


Subject(s)
Acrylamide/toxicity , Brain/drug effects , Melatonin/pharmacology , Oxidative Stress/drug effects , Animals , Brain/metabolism , Brain/pathology , Cell Survival/drug effects , DNA Damage/drug effects , Glutathione/metabolism , Glutathione Peroxidase/metabolism , Lipid Peroxidation/drug effects , Male , Malondialdehyde/metabolism , PC12 Cells , Rats , Rats, Sprague-Dawley , Reactive Oxygen Species/metabolism , Superoxide Dismutase/metabolism
17.
Sci Rep ; 5: 8725, 2015 Mar 04.
Article in English | MEDLINE | ID: mdl-25735640

ABSTRACT

Exhaled nitric oxide (eNO) is a useful biomarker of various physiological conditions, including asthma and other pulmonary diseases. Herein a fast and sensitive analytical method has been developed for the quantitative detection of eNO based on extractive electrospray ionization mass spectrometry (EESI-MS). Exhaled NO molecules selectively reacted with 2-phenyl-4, 4, 5, 5-tetramethylimidazoline-1-oxyl-3-oxide (PTIO) reagent, and eNO concentration was derived based on the EESI-MS response of 1-oxyl-2-phenyl-4, 4, 5, 5-tetramethylimidazoline (PTI) product. The method allowed quantification of eNO below ppb level (~0.02 ppbv) with a relative standard deviation (RSD) of 11.6%. In addition, eNO levels of 20 volunteers were monitored by EESI-MS over the time period of 10 hrs. Long-term eNO response to smoking a cigarette was recorded, and the observed time-dependent profile was discussed. This work extends the application of EESI-MS to small molecules (<30 Da) with low proton affinity and collision-induced dissociation efficiency, which are usually poorly visible by conventional ion trap mass spectrometers. Long-term quantitative profiling of eNO by EESI-MS opens new possibilities for the research of human metabolism and clinical diagnosis.


Subject(s)
Exhalation , Nitric Oxide/analysis , Smoking , Spectrometry, Mass, Electrospray Ionization/methods , Algorithms , Breath Tests/methods , Cyclic N-Oxides/chemistry , Humans , Imidazoles/chemistry , Models, Chemical , Nitric Oxide/chemistry
18.
J Nanosci Nanotechnol ; 13(6): 4247-51, 2013 Jun.
Article in English | MEDLINE | ID: mdl-23862481

ABSTRACT

In this paper, we report a preparation of CuZn dendritic microstructures through a tunable template-free electrochemical approach. By simply tunning the applied depositing current, the morphology of the product can be well controlled. The growth mechanism of CuZn dendritic alloys was also verified. The experimental results suggest that the growth of the grass-like structures obtained at 5 mA is driven by diffusion limited aggregation, while the driving force of the formation of CuZn dendrites obtained at 10 mA and 15 mA is gas bubbling worked as the dynamic template. The contact angle test shows the modified CuZn dendritic products possess superhydrophobic property. Additionally, through annealing of CuZn alloys in argon as the protective gas, derivative Cu/ZnO composite materials can be produced.


Subject(s)
Copper/chemistry , Zinc/chemistry , Electrochemical Techniques , Microscopy, Electron, Scanning , Wettability
19.
Zhonghua Gan Zang Bing Za Zhi ; 21(2): 111-5, 2013 Feb.
Article in Chinese | MEDLINE | ID: mdl-23663882

ABSTRACT

OBJECTIVE: To observe the effects of Wnt3a on proliferation and, activation of hepatic stellate cells (HSCs) and their the expression of the transforming growth factor beta (TGFb) and /Smad signaling factors of rat hepatic stellate cells line in vitro using a rat HSC line. METHODS: Synchronized HSC-T6 cells were stimulated with various concentrations of recombinant Wnt3a (50, 100, 200, 250 and 300 ng/mL). Unstimulated cells served as controls. Edu Effects on proliferation were determined by EdU (5-ethynyl-2'-deoxyuridine) incorporation assay and fluorescence microscopy.analysis was used to observe the proliferation of the hepatic stellate cells stimulated by different concentration of recombinant Wnt3a, and the Effects on the protein expression of TGFb/Smad signaling factors was assessed by western blot detection (gray-value analysis) of alpha-smooth muscle actin (a-SMA), a-SMA, TGFb1, Smad3, and and Smad7; glyceraldehyde 3-phosphate dehydrogenase (GAPDH) was detected as the normalization control in the hepatic stellate cells was observed by Western blot analysis .The correlation was also observed. The significance of inter-group differences was assessed by one-way ANOVA, and correlations were determined using bivariate statistical modeling. RESULTS: In general, HSC The proliferation of hepatic stellate cells increased after the addition of in response to Wnt3a stimulation for 24 h, reaching its peak at the maximum proliferation rate was observed with the 200 ng/mL Wnt3a concentration (63.00+/-2.30%), and it increased dramatically compared with those in which was significantly higher than the proliferation rates of the unstimulated control cells, and the cells stimulated with 50, 100 and 150 ng/mLl group (P less than 0.05), but the increase was not significantly different from that in the compared cells stimulated with 250 and 300 ng/mLl group,it had no obvious increase(P more than 0.05).; The Wnt3a stimulation also led to time-dependent increases in the protein expressions of a-SMA, TGFb1, and Smad3 increased with the addition of Wnt3a and the extension of time . For all three, The maximal amount of increased protein expression all reached to the was maximal produced by stimulation when hepatic stellate cells were treated by with 300 ng/mLl Wnt3a for 48 h hours,and the rations of(normalized gray- values:s of a-SMA, 1.0860+/-0.0101; TGFb1, 1.0346+/-0.0118; Smad3, to GAPDH were 1.0860+/-0.0101, 1.0346+/-0.0118, 1.0306+/-0.0122)respectively. However in contrast, the Wnt3a stimulation led to concentration- and time-dependent decreases in Smad7 expression varied inversely, with to them with the minimal ration of it to GAPDH the maximal decrease occurring with 300 ng/mL Wnt3a for 48 h (0.7736+/-0.0139) after being treated by 300 ng/ml Wnt3a for 48h. The comparison was remarkably discrepant, (P less than 0.05).There were positive correlations between a-SMA expression and was found to be positively correlated to TGFb1, Smad3 (r=0.968, P less than 0.05) and; Smad3 (r=0.997, P less than 0.01), but a-SMA and Smad7 had negatively correlated to Smad7 ion(r=0.960, P less than 0.05). CONCLUSION: Wnt3a can increase the stimulates proliferation as well as and activation of rat the hepatic stellate cells HSCs , and upregulate modifies the expression of TGFb/Smad signaling factors, of the hepatic stellate cells, and which may promote the hepatic fibrosis.


Subject(s)
Cell Proliferation/drug effects , Hepatic Stellate Cells/drug effects , Smad Proteins/metabolism , Transforming Growth Factor beta/metabolism , Wnt3A Protein/pharmacology , Animals , Cells, Cultured , Hepatic Stellate Cells/cytology , Hepatic Stellate Cells/metabolism , Rats , Signal Transduction
20.
Gene ; 508(2): 157-64, 2012 Oct 25.
Article in English | MEDLINE | ID: mdl-22903029

ABSTRACT

Toll-like receptors (TLRs) and the nuclear factor-kappa B (NF-κB) signaling transduction pathway play important roles in the pathogenesis of several chronic inflammatory diseases, but its function in oral lichen planus (OLP) remains unclear. In this study, we examined the expression of TLR4 and NF-κB-p65 and inflammatory cytokines TNF-α and IL-1ß by immunohistochemistry in OLP tissues, and found that TLR4 and NF-κB-p65 were significantly upregulated in OLP compared to normal oral mucosa (P<0.05). We used keratinocytes HaCaT stimulated with lipopolysaccharide (LPS) to simulate the local OLP immune environment to some extent. RT-PCR and immunoblotting analyses showed significant activation of TLR4 and NF-κB-p65 in the circumstance of LPS-induced inflammatory response. The high expression of TLR4 and NF-κB-p65 are correlated with expression of cytokines TNF-α and IL-1ß (P<0.05). We further showed that NF-κB could act as an anti-apoptotic molecule in OLP. We conclude that TLR4 and the NF-κB signaling pathway may interact with the perpetuation of OLP. Steroids and cyclosporine are effective in the treatment of symptomatic OLP. However, there was some weak evidence for the mechanism over Dexamethasone (DeX) and Cyclosporine A (CsA) for the palliation of symptomatic OLP. In the present study, we found that Dexamethasone and Cyclosporine A negatively regulated NF-κB signaling pathway under LPS simulation in HaCaT cells by inhibiting TLR4 expression, on the other hand, Cyclosporine A could inhibit HaCaT cell proliferation by the induction of the apoptosis of HaCaT cells to protect OLP from the destruction of epidermal cells effectively.


Subject(s)
Cyclosporine/pharmacology , Dexamethasone/pharmacology , Lichen Planus, Oral/drug therapy , Lichen Planus, Oral/metabolism , NF-kappa B/metabolism , Signal Transduction/drug effects , Toll-Like Receptor 4/metabolism , Anti-Inflammatory Agents/pharmacology , Apoptosis/drug effects , Blotting, Western , Cell Proliferation/drug effects , Cells, Cultured , Flow Cytometry , Humans , Immunoenzyme Techniques , Immunosuppressive Agents/pharmacology , Interleukin-1beta/metabolism , Keratinocytes/cytology , Keratinocytes/drug effects , Keratinocytes/metabolism , Lichen Planus, Oral/genetics , Lipopolysaccharides/pharmacology , Mouth Mucosa/cytology , Mouth Mucosa/drug effects , Mouth Mucosa/metabolism , NF-kappa B/genetics , RNA, Messenger/genetics , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Toll-Like Receptor 4/genetics , Tumor Necrosis Factor-alpha/metabolism
SELECTION OF CITATIONS
SEARCH DETAIL
...