The emergence and rapid spread of multidrug resistant (MDR) Gram-negative bacteria have posed a serious threat to global health and security. Because of the time-consuming, high cost and high risk of ...developing new antibiotics, a significant method is to use antibiotic adjuvants to revitalize the existing antibiotics. The purpose of the study is to research the traditional Chinese medicine baicalin with the function of inhibiting the efflux pump and EDTA whether their single or combination can increase the activity of colistin against colistin-resistant Salmonella in vitro and in vivo, and to explore its molecular mechanisms. In vitro antibacterial experiments, we have observed that baicalin and EDTA alone could enhance the antibacterial activity of colistin. At the same time, the combination of baicalin and EDTA also showed a stronger synergistic effect on colistin, reversing the colistin resistance of all Salmonella strains. Molecular docking and RT-PCR results showed that the combination of baicalin and EDTA not only affected the expression of mcr-1, but also was an effective inhibitor of MCR-1. In-depth synergistic mechanism analysis revealed that baicalin and EDTA enhanced colistin activity through multiple pathways, including accelerating the tricarboxylic acid cycle (TCA cycle), inhibiting the bacterial antioxidant system and lipopolysaccharide (LPS) modification, depriving multidrug efflux pump functions and attenuating bacterial virulence. In addition, the combinational therapy of colistin, baicalin and EDTA displayed an obvious reduction in bacterial loads cfus of liver and spleen compared with monotherapy and 2-drug combination therapy. In conclusion, our study indicates that the combination of baicalin and EDTA as a novel colistin adjuvant can provide a reliable basis for formulating the therapeutic regimen for colistin resistant bacterial infection.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
ICE
Hpa1
was identified in the genome of a serovar 8
Haemophilus parasuis
ST288 isolate YHP170504 from a case of swine lower respiratory tract infection. The aim of the present study was to ...characterize the integrative conjugative element ICE
Hpa1
and its multiresistance region. Susceptibility testing was determined by broth microdilution and the complete ICE
Hpa1
was identified by WGS analysis. The full sequence of ICE
Hpa1
was analyzed with bioinformatic tools. The presence of ICE
Hpa1
, its circular intermediate and integration site were confirmed by PCR and sequence analysis. Transfer of ICE
Hpa1
was confirmed by conjugation. ICE
Hpa1
has a size of 68,922 bp with 37.42% GC content and harbors 81 genes responsible for replication and stabilization, transfer, integration, and accessory functions, as well as seven different resistance genes
bla
Rob–
3
,
tet
(B),
aphA1
,
strA
,
strB
,
aac(6)′-Ie-aph(2′)-Ia
, and
sul2
. Conjugation experiments showed that ICE
Hpa1
could be transferred to
H. parasuis
V43 with frequencies of 6.1 × 10
–6
. This is the first time a multidrug-resistance ICE has been reported in
H. parasuis
. Seven different resistance genes were located on a novel integrative conjugative element ICE
Hpa1
, which suggests that the ICE
Hpa1
is capable of acquiring foreign genes and serving as a carrier for various resistance genes.
The objective of this study was to explore the genetic and biological features of the
tet
(M)-harboring plasmid pTS14 in
Salmonella enterica
strain S14 isolated from a chicken fecal sample. Plasmid ...pTS14 was identified by conjugation, S1-pulsed-field gel electrophoresis (PFGE), Southern hybridization, and plasmid sequencing. The biological characteristics of pTS14 were assessed via stability, growth kinetics, and starvation survival experiments. Strain S14, belonging to ST3007, harbored a 119-kb
tet
(M)-bearing IncF2:A1:B1 conjugative plasmid pTS14. The plasmid pTS14 contained a novel transposon Tn
6709
with the genetic structure IS
26
-
tnpA1
-
tnpA2
-Δ
orf13
-
LP
-
tet
(M)-
tnpX
-Δ
tnpR
-IS
26
, and the resistance genes
tet
(B),
tet
(D),
strAB
,
sul2
, and
bla
TEM–1b
. In addition, pTS14 was found to be highly stable in the recipient strain
E. coli
J53. The transconjugant TS14 exhibited a higher survival ratio than
E. coli
J53 under permanent starvation-induced stress. The
tet
(M)-bearing IncF2 epidemic plasmid lineage may accelerate the dissemination of
tet
(M) and other genes by coselection, which could constitute a potentially serious threat to clinical treatment regimens.
With the increasing and inappropriate use of colistin, the emerging colistin-resistant isolates have been frequently reported during the last few decades. Therefore, new potential targets and ...adjuvants to reverse colistin resistance are urgently needed. Our previous study has confirmed a marked increase of colistin susceptibility (16-fold compared to the wild-type Salmonella strain) of
overexpression strain JSΔ
Δ
::
/p
(simplified as JSΔΔ/p
). To searching for potential new drug targets, the transcriptome and metabolome analysis were carried out in this study. We found that the more susceptible strain JSΔΔ/p
displayed striking perturbations at both the transcriptomics and metabolomics levels. The virulence-related genes and colistin resistance-related genes (CRRGs) were significantly downregulated in JSΔΔ/p
. There were significant accumulation of citrate, α-ketoglutaric acid, and agmatine sulfate in JSΔΔ/p
, and exogenous supplement of them could synergistically enhance the bactericidal effect of colistin, indicating that these metabolites may serve as potential adjuvants for colistin therapy. Additionally, we also demonstrated that AcrB and CpxR could target the ATP and reactive oxygen species (ROS) generation, but not proton motive force (PMF) production pathway to potentiate antibacterial activity of colistin. Collectively, these findings have revealed several previously unknown mechanisms contributing to increased colistin susceptibility and identified potential targets and adjuvants for potentiating colistin treatment of Salmonella infections.
Emergence of multidrug-resistant (MDR) Gram-negative (G
) bacteria have led to the reconsideration of colistin as the last-resort therapeutic option for health care-associated infections. Finding new drug targets and strategies against the spread of MDR G
bacteria are global challenges for the life sciences community and public health. In this paper, we demonstrated the more susceptibility strain JSΔΔ/p
displayed striking perturbations at both the transcriptomics and metabolomics levels and revealed several previously unknown regulatory mechanisms of AcrB and CpxR on the colistin susceptibility. Importantly, we found that exogenous supplement of citrate, α-ketoglutaric acid, and agmatine sulfate could synergistically enhance the bactericidal effect of colistin, indicating that these metabolites may serve as potential adjuvants for colistin therapy. These results provide a theoretical basis for finding potential new drug targets and adjuvants.
The appearance and prevalence of multidrug-resistance (MDR) Gram-negative bacteria (GNB) have limited our antibiotic capacity to control bacterial infections. The clinical efficacy of colistin (COL), ...considered as the "last resort" for treating GNB infections, has been severely hindered by its increased use as well as the emergence and prevalence of mobile colistin resistance (MCR)-mediated acquired drug resistance. Identifying promising compounds to restore antibiotic activity is becoming an effective strategy to alleviate the crisis of increasing MDR. We first demonstrated that the combination of berberine (BBR) and EDTA substantially restored COL sensitivity against COL-resistant
and
. Molecular docking indicated that BBR can interact with MCR-1 and the efflux pump system AcrAB-TolC, and BBR combined with EDTA downregulated the expression level of
and
. Mechanically, BBR combined with EDTA could increase bacterial membrane damage, inhibit the function of multidrug efflux pump, and promote oxidative damage, thereby boosting the action of COL. In addition, transcriptome analysis found that the combination of BBR and EDTA can accelerate the tricarboxylic acid cycle, inhibit cationic antimicrobial peptide (CAMP) resistance, and attenuate
virulence. Notably, the combination of BBR and EDTA with COL significantly reduced the bacterial load in the liver and spleen of a mice model infected with
. Our findings revealed that BBR and EDTA can be used as adjuvants collectively with COL to synergistically reverse the COL resistance of bacteria.
Colistin is last-resort antibiotic used to treat serious clinical infections caused by MDR bacterial pathogens. The recent emergence of transferable plasmid-mediated COL resistance gene
has raised the specter of a rapid worldwide spread of COL resistance. Coupled with the fact of barren antibiotic development pipeline nowadays, a critical approach is to revitalize existing antibiotics using antibiotic adjuvants. Our research showed that berberine combined with EDTA effectively reversed COL resistance both
and
through multiple modes of action. The discovery of berberine in combination with EDTA as a new and safe COL adjuvant provides a therapeutic regimen for combating Gram-negative bacteria infections. Our findings provide a potential therapeutic option using existing antibiotics in combination with antibiotic adjuvants and address the prevalent infections caused by MDR Gram-negative pathogens worldwide.
As traditional techniques for microscopic identification of Chinese medicines currently lack objective and high-quality reference images, here we developed a systemic procedure to be used in ...microscopic identification of Chinese medicines, which would lead to more objective, effective and accurate identification process.
Spatholobi Caulis (Jixueteng in Chinese) was used as the specimen in the development of such procedure. Jixueteng samples were microscopically examined in bright- and dark-field microscopy. Microscopic images were obtained by regular, EDF, and image stitching techniques.
The microscopic images of the characteristics in pulverized Jixueteng were captured, thanks to EDF imaging and image stitching techniques which allowed the detailed and full sighting of each characteristic to be obtained simultaneously. Different layers in anatomical transverse section, including cork, phelloderm, cortex, phloem, cambium, xylem and pith, were distinctively observed. Moreover, by comparing images of bright- and dark-field microscopy, birefringent and non- birefringent components could readily be distinguished.
With application of the developed procedure, high-definition, panoramic and microscopic images were acquired, which could be used as the reference images for microscopic identification of Chinese medicines.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
Objective: Cynanchum stauntonii and Cynanchum glaucescens are botanical species of Baiqian (Cynanchi Stauntonii Rhizoma et Radix) in Chinese Pharmacopoeia, in which, however, there are no microscopic ...identification. Therefore, we provided the morphological and microscopic identification of the crude drug for updating Chinese Pharmacopoeia.
Methods: Twelve batches of C. stauntonii and three batches of C. glaucescens and their crude drugs were taxonomically, morphologically, and microscopically examined.
Results: Taxonomically, C. stauntonii had narrowly lanceolate leaves with acuminate apex and 5mm long petiole; Whereas C. glaucescens was oblong-lanceolate or oblong with rounded or acute apex in leaves, and had very short or no petiole. Morphologically, rhizomes of C. stauntonii and C. glaucescens both had hollow pith, but the hollow pith occupied about a half of the rhizome's diameter in C. stauntonii, whereas only a very small proportion of the overall diameter in C. glaucescens. Moreover, microscopic observation showed the difference in the proportion of xylem and in rhizome transverse-sections of the two species along with the difference in the size of the pith. Finally, laticifers and rhizome epidermal secretory cells were present in the powders of C. stauntonii, but absent from C. glaucescens.
Conclusion: Based on observation of morphological and microscopic characteristics, the two species can be distinguished by the size of the pith, proportion of xylem of rhizomes, and crude drug powder characters such as laticifers and secretory cells.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
We investigated the clinical characteristics of patients with acute aortic dissection (AAD) and miR-590-3p levels in serum, tissue, and vascular smooth muscle cells. The effect of miR-590-3p on the ...vascular smooth muscle cell phenotype was assessed, and the regulation of lysyl oxidase by miR-5903p was determined. C57BL/6 mice were used to investigate the incidence of AAD and effects of miR-5903p on AAD. The miR-590-3p levels were measured in the aortae of mice, and hematoxylin and eosin staining and Masson staining were performed to identify the morphological features of the aorta. Comparative analysis revealed significant differences in clinical characteristics between patients with AAD and healthy control subjects, with most patients with AAD exhibiting concomitant hypertension and nearly 50% having atherosclerosis. Lysyl oxidase was a direct target of miR-590-3p. Lysyl oxidase overexpression inhibited switching of the vascular smooth muscle cell phenotype from contractile to synthetic, but miR-590-3p overexpression significantly reversed this change. In the mouse model, miR-590-3p upregulation increased the incidence of AAD to 93.3%, and its incidence decreased to 13.3% after miR-590-3p inhibition. Hematoxylin and eosin and Masson staining revealed that the miR-590-3p agomiR group had a greater loss of the contractile phenotype in the dissected aortic wall and an increased number of muscle fibers in the aortic wall, which contributed to thickening of the aortic wall and the formation of a false lumen in aortic dissection. miR-590-3p might be pivotal in the pathogenesis of AAD. Thus, targeting miR-590-3p or its downstream pathways could represent a therapeutic approach for AAD.
•Silent myocardial infarction is more common in female than age-matched men patients.•Glutamate mediate depressor response to cardiac analgesia and peripheral nociception.•BRx afferent pathway plays ...key role in neuronal transmission of cardiac nociception.•Ah-type BRNs participate in sex differences between blood pressure and cardiac pain.
Silent myocardial infarction (MI) is critical for clinical practice with increasing risk for women and the cause remains a medical mystery. Upon the discovery of female-specific Ah-type baroreceptor neurons (BRNs), we hypothesize that glutamate mediates depressor response through afferent-specific expression of particular glutamate receptors (mGluRs) leading descending inhibition of cardiac nociception. In vivo, tail-flick reflex and electromyography were assessed to evaluate glutamate-mediated blood pressure regulation, peripheral and cardiac nociception. The results showed that glutamate decreased mean arterial pressure (MAP) and increased peripheral nociception. Interestingly, glutamate-mediated capsaicin-induced cardiac nociception was strongly reduced in female rats compared with males. Furthermore, Nodose (NG) microinjection of mGluR7 agonist significantly increased MAP in males and slightly decreased that in females. Even though mGluR8 direct activation intensified baroreceptor activation, the sensitivity was similar between sexes. In vitro, the expression profiles of mGluRs were investigated using Western blot and identified BRNs using single-cell qRT-PCR under ischemic conditions. Glutamate in serum, NG and nucleus tractus solitary (NTS) was raised significantly in the model rats of both sexes vs. sham-controls. Female-specific expression of mGluR7 in the baroreflex afferent pathway, especially higher expression in Ah-type BRNs, contributes significantly to cardiac analgesia, which may explain that the pathogenesis of silent MI occurs mainly in female patients. Therefore, higher expression of mGluR7 in female-specific subpopulation of Ah-type BRNs plays a critical role in cardiac analgesia and peripheral nociception.
Full text
Available for:
GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Abstract Background and Aim Helicobacter pylori infection is linked to various gastrointestinal conditions, such as chronic active gastritis, peptic ulcers, and gastric cancer. Traditional treatment ...options encounter difficulties due to antibiotic resistance and adverse effects. Therefore, the aim of this study was to explore the effectiveness of a new treatment plan that combines vonoprazan (VPZ), amoxicillin, and bismuth for the eradication of H. pylori . Methods A total of 600 patients infected with H. pylori were recruited for this multicenter randomized controlled trial. Patients treated for H. pylori elimination were randomly assigned at a 1:1 ratio to receive 14 days of vonoprazan‐based triple therapy (vonoprazan + amoxicillin + bismuth, group A) or standard quadruple therapy (esomeprazole + clarithromycin + amoxicillin + bismuth, group B). Compliance and adverse effects were tracked through daily medication and side effect records. All patients underwent a 13C/14C‐urea breath test 4 weeks after treatment completion. Results Intention‐to‐treat (ITT) and per‐protocol (PP) analyses revealed no substantial differences in H. pylori eradication rates between groups A and B (ITT: 83.7% vs 83.2%; PP: 90.9% vs 89.7%). However, significant differences were observed in the assessment of side effects (13.7% vs 28.6%, P < 0.001). Specifically, group A had significantly fewer “bitter mouths” than group B did (3.7% vs 16.2%, P < 0.001). Conclusion Triple therapy comprising vonoprazan (20 mg), amoxicillin (750 mg), and bismuth potassium citrate (220 mg) achieved a PP eradication rate ≥90%, paralleling standard quadruple therapy, and had fewer adverse events and lower costs (¥306.8 vs ¥645.8) for treatment‐naive patients.
Full text
Available for:
BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
PDF
