Anti-Saccharomyces cerevisiae antibodies (ASCAs) are present in 50-60% of patients with Crohn's disease (CD) and in 20-25% of their healthy relatives (HRs). The yeast, Candida albicans, has been ...shown to generate ASCAs, but the presence of C. albicans in the digestive tract of CD patients and their HRs has never been investigated. Therefore, we studied C. albicans carriage in familial CD and its correlation with ASCAs.
Study groups consisted of 41 CD families composed of 129 patients and 113 HRs, and 14 control families composed of 76 individuals. Mouth swabs and stool specimens were collected for isolation, identification, and quantification of yeasts. Serum samples were collected for detection of ASCAs and anti-C. albicans mannan antibodies (ACMAs).
C. albicans was isolated significantly more frequently from stool samples from CD patients (44%) and their HRs (38%) than from controls (22%) (P<0.05). The prevalence of ACMAs was similar between CD patients, their HRs, and controls (22, 19, and 21%, respectively, P=0.845), whereas the prevalence of ASCAs was significantly increased in CD families (72 and 34% in CD and HRs, respectively, in contrast to 4% in controls, P<0.0001). AMCA levels correlated with C. albicans colonization in all populations. ASCA levels correlated with C. albicans colonization in HRs but not in CD patients.
CD patients and their first-degree HRs are more frequently and more heavily colonized by C. albicans than are controls. ASCAs correlate with C. albicans colonization in HRs but not in CD. In HRs, ASCAs could result from an altered immune response to C. albicans. In CD, a subsequent alteration in sensing C. albicans colonization could occur with disease onset.
Toxic metals (such as lead, cadmium, and, to a lesser extent, aluminum) are detrimental to health when ingested in food or water or when inhaled. By interacting with heavy metals, gut and ...food-derived microbes can actively and/or passively modulate (by adsorption and/or sequestration) the bioavailability of these toxins inside the gut. This "intestinal bioremediation" involves the selection of safe microbes specifically able to immobilize metals. We used inductively coupled plasma mass spectrometry to investigate the in vitro ability of 225 bacteria to remove the potentially harmful trace elements lead, cadmium, and aluminum. Interspecies and intraspecies comparisons were performed among the Firmicutes (mostly lactic acid bacteria, including
spp., with some
,
, and
representatives), Actinobacteria, and Proteobacteria. The removal of a mixture of lead and cadmium was also investigated. Although the objective of the study was not to elucidate the mechanisms of heavy metal removal for each strain and each metal, we nevertheless identified promising candidate bacteria as probiotics for the intestinal bioremediation of Pb(II) and Cd(II).
Intestinal fibrosis is a frequent complication of Crohn's disease. However, the factors that cause chronicity and promote fibrogenesis are not yet understood.
In the present study, we evaluated the ...profibrotic effects of adherent-invasive Escherichia coli (AIEC) LF82 strain and Candida albicans in the gut.
Colonic fibrosis was induced in C57BL/6 mice by administration of three cycles of 2.5% (w/v) dextran sulfate sodium (DSS) for 5 weeks. LF82 and C. albicans were administered orally once at the start of each week or each cycle, respectively. Expression of markers of myofibroblast activation was determined in TGF-β1-stimulated human intestinal epithelial cells (IECs).
LF82 administration exacerbated fibrosis in DSS-treated mice, revealed by increased colonic collagen deposition and expression of the profibrotic genes Col1a1, Col3a1, Fn1 and Vim. This was accompanied by enhanced gene expression of proinflammatory cytokines and chemokines, as well as more recruited inflammatory cells into the intestine. LF82 also potentiated TGF-β1-stimulated epithelial-mesenchymal transition and myofibroblast activation in IECs, by further inducing gene expression of the main mesenchymal cell markers FN1 and VIM and downregulating the IEC marker OCLN. Proinflammatory cytokines were overexpressed with LF82 in TGF-β1-stimulated IECs. Conversely, C. albicans did not affect intestinal fibrosis progression in DSS-treated mice or myofibroblast activation in TGF-β1-stimulated IECs.
These results demonstrate that AIEC strain LF82, but not C. albicans, may play a major profibrogenic role in the gut.
Lavender aqueous extracts are widely used in the Moroccan traditional medicine for their antibacterial properties. However, previous research have generally focused on investigating the antibacterial ...activity of lavender essential oils. The aim of this study is to evaluate the antibacterial activity of the Moroccan
(Mill.) Cav. aqueous extract, alone, as well as in combination with extracts of other plant species known for their antibacterial activity:
Spenn.,
Vahl. and
Benth. We have tested the antibacterial activity of
,
,
and
aqueous extracts individually and in combination against 34 strains using the agar dilution method. The combination effect was evaluated using the fractional inhibitory concentration (FIC). Polyphenol and tannin contents were determined using Folin-Ciocalteu reagent, and then some phenolic compounds were identified using UHPLC-MS. All the extracts displayed a large spectrum of antibacterial activity, especially against staphylococci, streptococci,
and
. The minimum inhibitory concentration (MIC) values reached 0.15 ± 0.00 mg/mL for
tested with
and 0.20 ± 0.07 mg/mL for
tested with
or
. Association of the
extract with
,
and
showed synergistic effects (FIC ≤ 1). Moreover, the association of
with
was active against most of the Gram-negative strains resistant to the individual extracts. Determination of polyphenol and tannin contents showed the richness of the studied plants in these compounds. Additionally, chromatographic analysis demonstrated the high presence of rosmarinic acid in all the studied plant extracts. To our knowledge, this is the first study that shows the enhancing effect of the antibacterial activity of
aqueous extract combined with
,
and
. These results confirm the effectiveness of the plant mixtures commonly used by traditional healers in Morocco and suggest that
might be used as an antibacterial agent either alone or, more efficiently, in combination with
,
and
.
A preliminary ethnopharmacological survey, achieved in French Polynesia, led to the collection of the most cited plants among 63 species used to treat “infectious” diseases, with a description of ...their medicinal uses. Bibliographical investigations and antimicrobial screening permitted the selection of the botanical species Syzygium malaccense (Myrtaceae) for phytochemical analysis. Leaves of Syzygium malaccense were usually used in mixture with rhizomes of Curcuma longa to treat infectious diseases such as cystitis. The methanolic plant extracts were tested in vitro with an agar microdilution method on 33 bacteria strains and 1 yeast to obtain their Minimal Inhibitory Concentration (MIC), and cytotoxicity against HepG2 cells were evaluated. Antimicrobial synergistic effects of methanolic plant extracts from leaves of Syzygium malaccense and rhizomes from Curcuma longa were also evaluated. The bio-guided isolation of leaf extract from Syzygium malaccense led to the identification of seven alkyl-salicylic acids (anacardic acids or ginkgolic acids C15:0, C15:1, C17:0, C17:1, C17:2, C17:3 and C19:1) described for the first time in this species. All compounds were tested against Staphylococcus aureus (18.75 < MIC < 75.0 µg/mL), Streptococcus pyogenes (2.34 < MIC < 18.75 µg/mL) and Pseudomonas aeruginosa (MIC = 150 µg/mL), and their structure−activity relationships were discussed. The methanolic extract and salicylic derivatives from S. malaccense showed an interesting antimicrobial activity against Gram+ bacteria, without toxicity on hepG2 cells at 400 μg/mL. Moreover, these antibacterial compounds have already been studied for their anti-inflammatory activity, which supports the therapeutic interest of S. malaccense against infectious diseases.
Diabetic foot ulcers (DFU) are among the most common complications in diabetic patients and affect 6.8% of people worldwide. Challenges in the management of this disease are decreased blood ...diffusion, sclerotic tissues, infection, and antibiotic resistance. Hydrogels are now being used as a new treatment option since they can be used for drug delivery and to improve wound healing. This project aims to combine the properties of hydrogels based on chitosan (CHT) and the polymer of β cyclodextrin (PCD) for local delivery of cinnamaldehyde (CN) in diabetic foot ulcers. This work consisted of the development and characterisation of the hydrogel, the evaluation of the CN release kinetics and cell viability (on a MC3T3 pre-osteoblast cell line), and the evaluation of the antimicrobial and antibiofilm activity (
and
). The results demonstrated the successful development of a cytocompatible (ISO 10993-5) injectable hydrogel with antibacterial (99.99% bacterial reduction) and antibiofilm activity. Furthermore, a partial active molecule release and an increase in hydrogel elasticity were observed in the presence of CN. This leads us to hypothesise that a reaction between CHT and CN (a Schiff base) can occur and that CN could act as a physical crosslinker, thus improving the viscoelastic properties of the hydrogel and limiting CN release.
Cigarette smoke (CS) protects against intestinal inflammation during ulcerative colitis. Immunoregulatory mechanisms sustaining this effect remain unknown. The aim of this study was to assess the ...effects of CS on experimental colitis and to characterize the intestinal inflammatory response at the cellular and molecular levels. Using the InExpose® System, a smoking device accurately reproducing human smoking habit, we pre-exposed C57BL/6 mice for 2 weeks to CS, and then we induced colitis by administration of dextran sodium sulfate (DSS). This system allowed us to demonstrate that CS exposure improved colonic inflammation (significant decrease in clinical score, body weight loss and weight/length colonic ratio). This improvement was associated with a significant decrease in colonic proinflammatory Th1/Th17 cytokine expression, as compared to unexposed mice (TNF (p=0.0169), IFNγ (p<0.0001), and IL-17 (p=0.0008)). Smoke exposure also induced an increased expression of IL-10 mRNA (p=0.0035) and a marked recruitment of iNKT (invariant Natural Killer T; CD45+ TCRβ+ CD1d tetramer+) cells in the colon of DSS-untreated mice. Demonstration of the role of iNKT cells in CS-dependent colitis improvement was performed using two different strains of NKT cells deficient mice. Indeed, in Jα18KO and CD1dKO animals, CS exposure failed to induce significant regulation of DSS-induced colitis both at the clinical and molecular levels. Thus, our study demonstrates that iNKT cells are pivotal actors in the CS-dependent protection of the colon. These results highlight the role of intestinal iNKT lymphocytes and their responsiveness to environmental stimuli. Targeting iNKT cells would represent a new therapeutic way for inflammatory bowel diseases.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This study consisted of developing a dressing loaded with silver (Ag) and ibuprofen (IBU) that provides a dual therapy, antibacterial and antalgic, intended for infected painful wounds. Therefore, ...non-woven polyethyleneterephtalate (PET) textiles nonwovens were pre-treated by cyclodextrin crosslinked with citric acid by a pad/dry/cure process. Then, textiles were impregnated in silver solution followed by a thermal treatment and were then coated by Layer-by-Layer (L-b-L) deposition of a polyelectrolyte multilayer (PEM) system consisting of anionic water-soluble poly(betacyclodextrin citrate) (PCD) and cationic chitosan. Finally, ibuprofen lysinate (IBU-L) was loaded on the PEM coating. We demonstrated the complexation of IBU with native βCD and PCD by phase solubility diagram and 1H NMR. PEM system allowed complete IBU-L release in 6 h in PBS pH 7.4 batch (USP IV). On the other hand, microbiological tests demonstrated that loaded silver induced bacterial reduction of 4 Log10 against S. aureus and E. coli and tests revealed that ibuprofen lysinate loading did not interfere with the antibacterial properties of the dressing.
The aim of our study was to explore the potential value of metallic (Ag, Cu, and Zn) salts, polymer/metallic nanoparticles, and chlorhexidine (CHX) for improving the antimicrobial activity of calcium ...hydroxide (CH) against E. faecalis and C. albicans, associated with persistent endodontic infections. A first screening was performed by determining minimum inhibitory/bactericidal concentrations (MIC/MBC). Antimicrobial activity of the CH paste mixed with metallic salts, chitosan or cyclodextrin polymer metallic nanoparticles was compared to the antimicrobial activity of CH paste alone and CH + CHX using a time-kill kinetics assay. The effect of the antimicrobials on the rheological and the key mechanical properties were also examined. Copper and zinc were discarded because of their MIC/MBC values and silver because of its kill time curve profile. Except for a slower setting time after 24 h and a higher weight loss after 1 week of incubation, the mechanical behavior of the CH paste was unaffected by the addition of CHX. Polymeric/metallic nanoparticles failed to potentiate the antimicrobial effect of CH. By contrast, CHX increased this effect and thus could help eradicate E. faecalis associated with persistent root canal infections without altering the desired key physical properties of the CH paste.
Endo-periodontal lesions are challenging clinical situations where both the supporting tissues and the root canal of the same tooth are infected. In the present study, chlorhexidine (CHX)-loaded ...calcium hydroxide (CH) pastes were used as intracanal medications (ICMs). They were prepared and tested on pathogens found in both the root canal and the periodontal pocket. Exposure to 0.5% and 1% CHX-loaded ICMs decreased the growth of Porphyromonas gingivalis and was effective in eradicating or inhibiting an Enterococcus faecalis biofilm. CH was injected into the root canal of extracted human teeth immersed in deionized water. CHX-loaded ICMs resulted in the transradicular diffusion of active components outside the tooth through the apex and the lateral dentinal tubules, as shown by the release of CHX (from 3.99 µg/mL to 51.28 µg/mL) and changes in pH (from 6.63 to 8.18) and calcium concentrations (from 2.42 ppm to 14.67 ppm) after 7 days. The 0.5% CHX-loaded ICM was non-toxic and reduced the release of IL-6 by periodontal cells stimulated by P. gingivalis lipopolysaccharides. Results indicate that the root canal may serve as a reservoir for periodontal drug delivery and that CHX-based ICMs can be an adjuvant for the control of infections and inflammation in endo-periodontal lesions.
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