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1.
Cell Rep ; 42(5): 112494, 2023 05 30.
Article in English | MEDLINE | ID: mdl-37167061

ABSTRACT

During inflammation, the skin deploys antimicrobial peptides (AMPs) yet during allergic inflammation it becomes more susceptible to Staphylococcus aureus. To understand this contradiction, single-cell sequencing of Il4ra-/- mice combined with skin microbiome analysis reveals that lower production of AMPs from interleukin-4 receptor α (IL-4Rα) activation selectively inhibits survival of antibiotic-producing strains of coagulase-negative Staphylococcus (CoNS). Diminished AMPs under conditions of T helper type 2 (Th2) inflammation enable expansion of CoNS strains without antibiotic activity and increase Staphylococcus aureus (S. aureus), recapitulating the microbiome on humans with atopic dermatitis. This response is rescued in Camp-/- mice or after topical steroids, since further inhibition of AMPs enables survival of antibiotic-producing CoNS strains. In conditions of Th17 inflammation, a higher expression of host AMPs is sufficient to directly inhibit S. aureus survival. These results show that antimicrobials produced by the host and commensal bacteria each act to control S. aureus on the skin.


Subject(s)
Methicillin-Resistant Staphylococcus aureus , Staphylococcal Infections , Humans , Animals , Mice , Staphylococcus aureus/metabolism , Antimicrobial Peptides , Skin/microbiology , Inflammation , Bacteria , Staphylococcus , Anti-Bacterial Agents/metabolism
2.
Article in English | MEDLINE | ID: mdl-35329209

ABSTRACT

Previous menthol studies have demonstrated ergogenic effects in endurance-based activity. However, there is a need for research in sports whose physiological requirements exceed maximal aerobic capacity. This study assessed the effects of 0.1% menthol mouth-rinsing upon a modified three-minute maximal test in the heat (33.0 ± 3.0 °C; RH 46.0 ± 5.0%). In a randomised crossover single blind placebo-controlled study, 11 participants completed three modified maximal tests, where each trial included a different mouth rinse: either menthol (MEN), cold water (WAT) or placebo (PLA). Participants were asked to rate their thermal comfort (TC), thermal sensation (TS) and rating of perceived exertion (RPE) throughout the test. Heart rate, core temperature, oxygen uptake (VO2), ventilation (VE) and respiratory exchange ratio (RER) were monitored continuously throughout the test, alongside cycling power variables (W; W/kg). A blood lactate (BLa) level was taken pre- and post- test. Small to moderate effects (Cohen's d and accompanying 90% confidence intervals) between solutions MEN, WAT and PLA were observed towards the end of the test in relation to relative power. Specifically, from 75-105 s between solutions MEN and WAT (ES: 0.795; 90% CI: 0.204 to 1.352) and MEN and PLA (ES: 1.059; 90% CI: 0.412 to 1.666), this continued between MEN and WAT (ES: 0.729; 90% CI: 0.152 to 1.276) and MEN and PLA (ES: 0.791; 90% CI: 0.202 to 1.348) from 105-135 s. Between 135-165 s there was a moderate difference between solutions MEN and WAT (ES: 1.058; 90% CI: 0.411 to 1.665). This indicates participants produced higher relative power for longer durations with the addition of the menthol mouth rinse, compared to cold water or placebo. The use of menthol (0.1%) as a mouth rinse showed small performance benefits for short duration high intensity exercise in the heat.


Subject(s)
Menthol , Mouthwashes , Bicycling/physiology , Hot Temperature , Humans , Polyesters , Single-Blind Method , Water
3.
JAMA Dermatol ; 2021 Jun 16.
Article in English | MEDLINE | ID: mdl-34132739

ABSTRACT

IMPORTANCE: Atopic dermatitis (AD) can be negatively affected by Staphylococcus aureus. The skin microbiome of AD is deficient in coagulase-negative Staphylococcus (CoNS) that can kill S aureus. OBJECTIVE: To evaluate if the antimicrobial-producing CoNS (CoNS-AM+) of a patient with AD can be autologously reintroduced to the same patient to inhibit survival of S aureus and improve clinical outcomes. DESIGN, SETTING, AND PARTICIPANTS: This double-blind, vehicle-controlled, single-center randomized clinical trial of 11 adult patients with moderate to severe AD who were randomized to receive either an autologous CoNS-AM+ (n = 5) or the vehicle (n = 6) was conducted between April 2016 and May 2018. The data were analyzed from May 2018 to July 2019. INTERVENTIONS: Autologous CoNS-AM+ was isolated from swabs that were obtained from the nonlesional skin of each patient with AD, expanded by culture, and then reapplied topically to the forearms at a concentration of 107 colony-forming units/g. MAIN OUTCOMES AND MEASURES: The primary end point of this study was to assess S aureus abundance after 1 week of application of autologous CoNS-AM+ on patients with AD by culture-based and DNA-based methods. The secondary end points were to assess the safety and clinical outcomes. RESULTS: Eleven patients (4 men [36.4%] and 7 women [63/6%]) were recruited based on the inclusion criteria. There were no serious adverse events in groups treated with autologous CoNS-AM+ or the vehicle. Staphylococcus aureus colonization on lesional skin at the end of treatment on patients who were treated with autologous CoNS-AM+ (mean of log10 ratio to baseline, -1.702; 95% CI, -2.882 to -0.523) was reduced by 99.2% compared with vehicle treatment (mean of log10 ratio to baseline, 0.671; 95% CI, -0.289 to 1.613; P = .01) and persisted for 4 days after treatment (CoNS-AM+: mean of log10 ratio to baseline, -1.752; 95% CI, -3.051 to -0.453; vehicle: mean of log10 ratio to baseline, -0.003; 95% CI, -1.083 to 1.076; P = .03). Importantly, local Eczema Area And Severity Index scores that were assessed at day 11 on patients who received CoNS-AM+ (mean of percentage change, -48.45; 95% CI, -84.34 to -12.55) were significantly improved compared with vehicle treatment (mean of percentage change, -4.52; 95% CI, -36.25 to 27.22; P = .04). CONCLUSIONS AND RELEVANCE: The data from this randomized clinical trial suggest that bacteriotherapy with an autologous strain of skin commensal bacteria can safely decrease S aureus colonization and improve disease severity. Although larger studies will be needed, this personalized approach for S aureus reduction may provide an alternative treatment for patients with AD beyond antibiotics, immunosuppression, and immunomodulation. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03158012.

4.
Nat Med ; 27(4): 700-709, 2021 04.
Article in English | MEDLINE | ID: mdl-33619370

ABSTRACT

Staphylococcus aureus colonizes patients with atopic dermatitis (AD) and exacerbates disease by promoting inflammation. The present study investigated the safety and mechanisms of action of Staphylococcus hominis A9 (ShA9), a bacterium isolated from healthy human skin, as a topical therapy for AD. ShA9 killed S. aureus on the skin of mice and inhibited expression of a toxin from S. aureus (psmα) that promotes inflammation. A first-in-human, phase 1, double-blinded, randomized 1-week trial of topical ShA9 or vehicle on the forearm skin of 54 adults with S. aureus-positive AD (NCT03151148) met its primary endpoint of safety, and participants receiving ShA9 had fewer adverse events associated with AD. Eczema severity was not significantly different when evaluated in all participants treated with ShA9 but a significant decrease in S. aureus and increased ShA9 DNA were seen and met secondary endpoints. Some S. aureus strains on participants were not directly killed by ShA9, but expression of mRNA for psmα was inhibited in all strains. Improvement in local eczema severity was suggested by post-hoc analysis of participants with S. aureus directly killed by ShA9. These observations demonstrate the safety and potential benefits of bacteriotherapy for AD.


Subject(s)
Dermatitis, Atopic/microbiology , Dermatitis, Atopic/therapy , Skin/microbiology , Staphylococcus hominis/physiology , Administration, Topical , Adolescent , Adult , Aged , Aged, 80 and over , Animals , Bacterial Proteins/metabolism , Bacteriocins/pharmacology , Colony Count, Microbial , Humans , Inflammation/complications , Inflammation/pathology , Mice, Inbred BALB C , Microbial Sensitivity Tests , Microbial Viability/drug effects , Middle Aged , Peptides, Cyclic/metabolism , Reproducibility of Results , Skin/drug effects , Skin/pathology , Staphylococcal Infections/microbiology , Staphylococcal Infections/therapy , Staphylococcus aureus/drug effects , Staphylococcus aureus/growth & development , Staphylococcus aureus/physiology , Transcription, Genetic/drug effects , Treatment Outcome , Virulence Factors/metabolism , Young Adult
5.
Health Technol Assess ; 25(11): 1-58, 2021 02.
Article in English | MEDLINE | ID: mdl-33632377

ABSTRACT

BACKGROUND: Anaemia affects 30-50% of patients before they undergo major surgery. Preoperative anaemia is associated with increased need for blood transfusion, postoperative complications and worse patient outcomes after surgery. International guidelines support the use of intravenous iron to correct anaemia in patients before surgery. However, the use of preoperative intravenous iron for patient benefit has not been assessed in the setting of a formal clinical trial. OBJECTIVES: To assess if intravenous iron given to patients with anaemia before major abdominal surgery is beneficial by reducing transfusion rates, postoperative complications, hospital stay and re-admission to hospital, and improving quality of life outcomes. DESIGN: A multicentre, double-blinded, randomised, controlled, Phase III clinical trial, with 1 : 1 randomisation comparing placebo (normal saline) with intravenous iron (intravenous ferric carboxymaltose 1000 mg). Randomisation and treatment allocation were by a secure web-based service. SETTING: The study was conducted across 46 hospitals in England, Scotland and Wales between September 2013 and September 2018. PARTICIPANTS: Patients aged > 18 years, undergoing elective major open abdominal surgery, with anaemia [Hb level of > 90 g/l and < 120 g/l (female patients) and < 130 g/l (male patients)] who could undergo randomisation and treatment 10-42 days before their operation. INTERVENTION: Double-blinded study comparing placebo of normal saline with 1000 mg of ferric carboxymaltose administered 10-42 days prior to surgery. MAIN OUTCOME MEASURES: Co-primary end points were risk of blood transfusion or death at 30 days postoperatively, and rate of blood transfusions at 30 days post operation. RESULTS: A total of 487 patients were randomised (243 given placebo and 244 given intravenous iron), of whom 474 completed the trial and provided data for the analysis of the co-primary end points. The use of intravenous iron increased preoperative Hb levels (mean difference 4.7 g/l, 95% confidence interval 2.7 to 6.8 g/l; p < 0.0001), but had no effect compared with placebo on risk of blood transfusion or death (risk ratio 1.03, 95% confidence interval 0.78 to 1.37; p = 0.84; absolute risk difference +0.8%, 95% confidence interval -7.3% to 9.0%), or rates of blood transfusion (rate ratio 0.98, 95% confidence interval 0.68 to 1.43; p = 0.93; absolute rate difference 0.00, 95% confidence interval -0.14 to 0.15). There was no difference in postoperative complications or hospital stay. The intravenous iron group had higher Hb levels at the 8-week follow-up (difference in mean 10.7 g/l, 95% confidence interval 7.8 to 13.7 g/l; p < 0.0001). There were a total of 71 re-admissions to hospital for postoperative complications in the placebo group, compared with 38 re-admissions in the intravenous iron group (rate ratio 0.54, 95% confidence interval 0.34 to 0.85; p = 0.009). There were no differences between the groups in terms of mortality (two per group at 30 days post operation) or in any of the prespecified safety end points or serious adverse events. CONCLUSIONS: In patients with anaemia prior to elective major abdominal surgery, there was no benefit from giving intravenous iron before the operation. FUTURE WORK: The impact of iron repletion on recovery from postoperative anaemia, and the association with reduced re-admission to hospital for complications, should be investigated. LIMITATIONS: In the preoperative intravenous iron to treat anaemia in major surgery (PREVENTT) trial, all patients included had anaemia and only 20% had their anaemia corrected before surgery. The definition and causality of iron deficiency in this setting is not clear. TRIAL REGISTRATION: Current Controlled Trials ISRCTN67322816 and ClinicalTrials.gov NCT01692418. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25 No. 11. See the NIHR Journals Library website for further project information.


In patients undergoing major surgery, anaemia (low blood count) is a common problem. Anaemia is often a consequence of the disease necessitating surgery and can make people feel tired and unwell. Anaemia increases the need for a blood transfusion at the time of surgery, and patients with anaemia have more complications from surgery, prolonged hospital stay and delayed recovery. Iron deficiency is the most common cause of anaemia. An iron infusion has been shown to be effective to rapidly treat anaemia, but it is not known if this is effective in treating anaemia in the presurgical setting, and whether or not this may benefit patients. The main aim of this study was to assess if intravenous iron can treat anaemia in patients before major surgery and if this will reduce the need for blood transfusion, make patients feel better and, consequently, help them do better during and after surgery. A total of 487 patients with anaemia were recruited from 46 UK hospitals before major abdominal surgery. Patients were randomly allocated to receive an infusion of iron or placebo 10 days to 6 weeks before their surgery. Patients were followed up at 8 weeks and 6 months after their surgery. Intravenous iron increased the blood count in patients before surgery. There was no difference in blood transfusion rates or patient deaths between those who received intravenous iron and those who received placebo. Similarly, there was no difference in the patients' postoperative complications or length of hospital stay. Patients who received iron had a higher blood count at 8 weeks and 6 months post operation and there were fewer re-admissions to hospital for complications. In conclusion, for patients undergoing major surgery, giving intravenous iron to treat anaemia before the operation did not reduce the need for blood transfusion. Further work is needed to evaluate whether or not there is any benefit after discharge from hospital.


Subject(s)
Anemia , Iron , Abdomen/surgery , Elective Surgical Procedures , Female , Humans , Male , Quality of Life
6.
J Allergy Clin Immunol ; 147(3): 955-966.e16, 2021 03.
Article in English | MEDLINE | ID: mdl-32634452

ABSTRACT

BACKGROUND: Staphylococcus aureus and Staphylococcus epidermidis are the most abundant bacteria found on the skin of patients with atopic dermatitis (AD). S aureus is known to exacerbate AD, whereas S epidermidis has been considered a beneficial commensal organism. OBJECTIVE: In this study, we hypothesized that S epidermidis could promote skin damage in AD by the production of a protease that damages the epidermal barrier. METHODS: The protease activity of S epidermidis isolates was compared with that of other staphylococcal species. The capacity of S epidermidis to degrade the barrier and induce inflammation was examined by using human keratinocyte tissue culture and mouse models. Skin swabs from atopic and healthy adult subjects were analyzed for the presence of S epidermidis genomic DNA and mRNA. RESULTS: S epidermidis strains were observed to produce strong cysteine protease activity when grown at high density. The enzyme responsible for this activity was identified as EcpA, a cysteine protease under quorum sensing control. EcpA was shown to degrade desmoglein-1 and LL-37 in vitro, disrupt the physical barrier, and induce skin inflammation in mice. The abundance of S epidermidis and expression of ecpA mRNA were increased on the skin of some patients with AD, and this correlated with disease severity. Another commensal skin bacterial species, Staphylococcus hominis, can inhibit EcpA production by S epidermidis. CONCLUSION: S epidermidis has commonly been regarded as a beneficial skin microbe, whereas S aureus has been considered deleterious. This study suggests that the overabundance of S epidermidis found on some atopic patients can act similarly to S aureus and damage the skin by expression of a cysteine protease.


Subject(s)
Bacterial Proteins/metabolism , Cysteine Proteases/metabolism , Dermatitis, Atopic/microbiology , Microbiota , Skin/microbiology , Staphylococcal Skin Infections/microbiology , Staphylococcus epidermidis/enzymology , Animals , Antimicrobial Cationic Peptides/metabolism , Cells, Cultured , DNA, Bacterial/genetics , Dermatitis, Atopic/pathology , Desmoglein 1/metabolism , Humans , Keratinocytes/microbiology , Keratinocytes/pathology , Mice , Mice, Inbred C57BL , Severity of Illness Index , Skin/pathology , Staphylococcal Skin Infections/pathology , Cathelicidins
7.
Lancet ; 396(10259): 1353-1361, 2020 10 24.
Article in English | MEDLINE | ID: mdl-32896294

ABSTRACT

BACKGROUND: Preoperative anaemia affects a high proportion of patients undergoing major elective surgery and is associated with poor outcomes. We aimed to test the hypothesis that intravenous iron given to anaemic patients before major open elective abdominal surgery would correct anaemia, reduce the need for blood transfusions, and improve patient outcomes. METHODS: In a double-blind, parallel-group randomised trial, we recruited adult participants identified with anaemia at preoperative hospital visits before elective major open abdominal surgery at 46 UK tertiary care centres. Anaemia was defined as haemoglobin less than 130 g/L for men and 120 g/L for women. We randomly allocated participants (1:1) via a secure web-based service to receive intravenous iron or placebo 10-42 days before surgery. Intravenous iron was administered as a single 1000 mg dose of ferric carboxymaltose in 100 mL normal saline, and placebo was 100 mL normal saline, both given as an infusion over 15 min. Unblinded study personnel prepared and administered the study drug; participants and other clinical and research staff were blinded to treatment allocation. Coprimary endpoints were risk of the composite outcome of blood transfusion or death, and number of blood transfusions from randomisation to 30 days postoperatively. The primary analysis included all randomly assigned patients with data available for the primary endpoints; safety analysis included all randomly assigned patients according to the treatment received. This study is registered, ISRCTN67322816, and is closed to new participants. FINDINGS: Of 487 participants randomly assigned to placebo (n=243) or intravenous iron (n=244) between Jan 6, 2014, and Sept 28, 2018, complete data for the primary endpoints were available for 474 (97%) individuals. Death or blood transfusion occurred in 67 (28%) of the 237 patients in the placebo group and 69 (29%) of the 237 patients in the intravenous iron group (risk ratio 1·03, 95% CI 0·78-1·37; p=0·84). There were 111 blood transfusions in the placebo group and 105 in the intravenous iron group (rate ratio 0·98, 95% CI 0·68-1·43; p=0·93). There were no significant differences between the two groups for any of the prespecified safety endpoints. INTERPRETATION: Preoperative intravenous iron was not superior to placebo to reduce need for blood transfusion when administered to patients with anaemia 10-42 days before elective major abdominal surgery. FUNDING: UK National Institute of Health Research Health Technology Assessment Program.


Subject(s)
Abdomen/surgery , Administration, Intravenous , Anemia/drug therapy , Iron/administration & dosage , Preoperative Care , Aged , Double-Blind Method , Elective Surgical Procedures , Female , Humans , Male , Treatment Outcome , United Kingdom
8.
Cell Rep ; 30(9): 2923-2933.e7, 2020 03 03.
Article in English | MEDLINE | ID: mdl-32130897

ABSTRACT

Netherton syndrome (NS) is a monogenic skin disease resulting from loss of function of lymphoepithelial Kazal-type-related protease inhibitor (LEKTI-1). In this study we examine if bacteria residing on the skin are influenced by the loss of LEKTI-1 and if interaction between this human gene and resident bacteria contributes to skin disease. Shotgun sequencing of the skin microbiome demonstrates that lesional skin of NS subjects is dominated by Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S. epidermidis). Isolates of either species from NS subjects are able to induce skin inflammation and barrier damage on mice. These microbes promote skin inflammation in the setting of LEKTI-1 deficiency due to excess proteolytic activity promoted by S. aureus phenol-soluble modulin α as well as increased bacterial proteases staphopain A and B from S. aureus or EcpA from S. epidermidis. These findings demonstrate the critical need for maintaining homeostasis of host and microbial proteases to prevent a human skin disease.


Subject(s)
Netherton Syndrome/microbiology , Netherton Syndrome/pathology , Peptide Hydrolases/metabolism , Skin/microbiology , Skin/pathology , Staphylococcus aureus/enzymology , Staphylococcus epidermidis/enzymology , Adolescent , Adult , Animals , Bacterial Toxins/metabolism , Child , Colony Count, Microbial , Epidermis , Female , Humans , Male , Mice, Inbred C57BL , Microbiota , Middle Aged , Netherton Syndrome/enzymology , Phenols , Solubility
9.
Cell Rep ; 30(1): 61-68.e4, 2020 01 07.
Article in English | MEDLINE | ID: mdl-31914398

ABSTRACT

Staphylococcus aureus is a major human bacterial pathogen responsible for deep tissue skin infections. Recent observations have suggested that rapid, localized digestion of hyaluronic acid in the extracellular matrix (ECM) of the dermis may influence bacterial invasion and tissue inflammation. In this study we find that cell migration-inducing protein (Cemip) is the major inducible gene responsible for hyaluronan catabolism in mice. Cemip-/- mice failed to digest hyaluronan and had significantly less evidence of infection after intradermal bacterial challenge by S. aureus. Stabilization of large-molecular-weight hyaluronan enabled increased expression of cathelicidin antimicrobial peptide (Camp) that was due in part to enhanced differentiation of preadipocytes to adipocytes, as seen histologically and by increased expression of Pref1, PPARg, and Adipoq. Cemip-/- mice challenged with S. aureus also had greater IL-6 expression and neutrophil infiltration. These observations describe a mechanism for hyaluronan in the dermal ECM to regulate tissue inflammation and host antimicrobial defense.


Subject(s)
Host-Pathogen Interactions , Hyaluronic Acid/metabolism , Hyaluronoglucosaminidase/metabolism , Staphylococcal Infections/microbiology , Staphylococcus aureus/physiology , Adipogenesis , Animals , Dermis/microbiology , Dermis/pathology , Hyaluronoglucosaminidase/deficiency , Inflammation/pathology , Mice, Inbred C57BL , Mice, Knockout
10.
Sci Adv ; 4(2): eaao4502, 2018 02.
Article in English | MEDLINE | ID: mdl-29507878

ABSTRACT

We report the discovery that strains of Staphylococcus epidermidis produce 6-N-hydroxyaminopurine (6-HAP), a molecule that inhibits DNA polymerase activity. In culture, 6-HAP selectively inhibited proliferation of tumor lines but did not inhibit primary keratinocytes. Resistance to 6-HAP was associated with the expression of mitochondrial amidoxime reducing components, enzymes that were not observed in cells sensitive to this compound. Intravenous injection of 6-HAP in mice suppressed the growth of B16F10 melanoma without evidence of systemic toxicity. Colonization of mice with an S. epidermidis strain producing 6-HAP reduced the incidence of ultraviolet-induced tumors compared to mice colonized by a control strain that did not produce 6-HAP. S. epidermidis strains producing 6-HAP were found in the metagenome from multiple healthy human subjects, suggesting that the microbiome of some individuals may confer protection against skin cancer. These findings show a new role for skin commensal bacteria in host defense.


Subject(s)
Skin Neoplasms/microbiology , Staphylococcus epidermidis/physiology , Adenine/analogs & derivatives , Adenine/chemistry , Adenine/metabolism , Adenine/pharmacology , Animals , Cell Line, Tumor , Cell Proliferation/drug effects , Female , Humans , Melanoma, Experimental/pathology , Membrane Proteins/metabolism , Mice , Skin/drug effects , Skin/microbiology , Skin Neoplasms/pathology , Staphylococcus epidermidis/drug effects , Staphylococcus epidermidis/isolation & purification , Ultraviolet Rays
13.
PLoS One ; 12(6): e0180156, 2017.
Article in English | MEDLINE | ID: mdl-28666002

ABSTRACT

Insertion sequence elements (IS elements) are proposed to play major roles in shaping the genetic and phenotypic landscapes of prokaryotic cells. Recent evidence has raised the possibility that environmental stress conditions increase IS hopping into new sites, and often such hopping has the phenotypic effect of relieving the stress. Although stress-induced targeted mutations have been reported for a number of E. coli genes, the glpFK (glycerol utilization) and the cryptic bglGFB (ß-glucoside utilization) systems are among the best characterized where the effects of IS insertion-mediated gene activation are well-characterized at the molecular level. In the glpFK system, starvation of cells incapable of utilizing glycerol leads to an IS5 insertion event that activates the glpFK operon, and enables glycerol utilization. In the case of the cryptic bglGFB operon, insertion of IS5 (and other IS elements) into a specific region in the bglG upstream sequence has the effect of activating the operon in both growing cells, and in starving cells. However, a major unanswered question in the glpFK system, the bgl system, as well as other examples, has been why the insertion events are promoted at specific locations, and how the specific stress condition (glycerol starvation for example) can be mechanistically linked to enhanced insertion at a specific locus. In this paper, we show that a specific DNA structural feature (superhelical stress-induced duplex destabilization, SIDD) is associated with "stress-induced" IS5 insertion in the glpFK, bglGFB, flhDC, fucAO and nfsB systems. We propose a speculative mechanistic model that links specific environmental conditions to the unmasking of an insertional hotspot in the glpFK system. We demonstrate that experimentally altering the predicted stability of a SIDD element in the nfsB gene significantly impacts IS5 insertion at its hotspot.


Subject(s)
DNA Transposable Elements , DNA/chemistry , Nucleic Acid Conformation , Transcriptional Activation , Alleles , Base Sequence , DNA/genetics , Escherichia coli/genetics , Mutation , Operon , Promoter Regions, Genetic
15.
BMJ Open ; 7(4): e014872, 2017 04 18.
Article in English | MEDLINE | ID: mdl-28420664

ABSTRACT

INTRODUCTION: Preoperative anaemia is linked to poor postsurgical outcome, longer hospital stays, greater risk of complications and mortality. Currently in the UK, some sites have developed anaemia clinics or pathways that use intravenous iron to correct iron deficiency anaemia prior to surgery as their standard of care. Although intravenous iron has been observed to be effective in a variety of patient settings, there is insufficient evidence in its use in cardiac and vascular patients. The aim of this study is to observe the impact and effect of anaemia and its management in patients undergoing cardiac and vascular surgery. In addition, the UK Cardiac and Vascular Surgery Interventional Anaemia Response (CAVIAR) Study is also a feasibility study with the aim to establish anaemia management pathways in the preoperative setting to inform the design of future randomised controlled trials. METHODS AND ANALYSIS: The UK CAVIAR Study is a multicentre, stepped, observational study, in patients awaiting major cardiac or vascular surgery. We will be examining different haematological variables (especially hepcidin), functional capacity and patient outcome. Patients will be compared based on their anaemia status, whether they received intravenous iron in accordance to their hospital's preoperative pathway, and their disease group. The primary outcomes are the change in haemoglobin levels from baseline (before treatment) to before surgery; and the number of successful patients recruited and consented (feasibility). The secondary outcomes will include changes in biomarkers of iron deficiency, length of stay, quality of life and postoperative recovery. ETHICS AND DISSEMINATION: The study protocol was approved by the London-Westminster Research Ethics Committee (15/LO/1569, 27 November 2015). NHS approval was also obtained with each hospital trust. The findings of the study will be published in peer-reviewed journals. TRIAL REGISTRATION NUMBER: Clinical Trials registry (NCT02637102) and the ISRCTN registry (ISRCTN55032357).


Subject(s)
Anemia/therapy , Blood Transfusion/statistics & numerical data , Cardiac Surgical Procedures , Iron/therapeutic use , Postoperative Complications/therapy , Preoperative Care/methods , Vascular Surgical Procedures , Administration, Intravenous , Anemia/metabolism , Anemia, Iron-Deficiency/metabolism , Anemia, Iron-Deficiency/therapy , Exercise Test , Ferritins/metabolism , Hemoglobins/metabolism , Hepcidins/metabolism , Humans , Postoperative Complications/metabolism , United Kingdom , Walk Test
17.
Vascular ; 23(6): 630-6, 2015 Dec.
Article in English | MEDLINE | ID: mdl-25819513

ABSTRACT

INTRODUCTION: Aortoiliac arterial occlusive disease is frequently encountered in the management of lower limb vascular insufficiency. We report our experience with covered balloon-expandable stents for treatment of TASC D lesions of the abdominal aorta and common iliac arteries. METHODS: A retrospective study of 30 patients who underwent aortoiliac stenting with the Atrium Advanta V12 from March 2010 to September 2012 was conducted. Patient demographic data, clinical signs and symptoms and procedural details were recorded. Outcomes assessed were primary patency, secondary patency, technical success, complications, limb salvage and survival. RESULTS: Median age was 67 years (range 48-84) and 40% of patients underwent treatment for critical limb ischaemia. Median follow-up was 13 months (range 3-38 months). Stent configuration comprised of long iliac stents in 20 patients, a large diameter aortic stent with iliac stenting in six patients, and aortic stent alone in four patients. Radiological success was achieved in 100% and the complication rate was 6%. Primary patency at 6, 12 and 24 months was 97%, 90% and 79%, respectively. Four cases of in-stent stenosis were reported, with three of these undergoing re-interventions resulting in a secondary patency rate of 97% at the end of follow-up. One patient death occurred within the follow-up period. DISCUSSION: This case series demonstrates that treatment of complex aortoiliac occlusive disease with covered balloon-expandable stents can have acceptable results with good patency and good clinical outcome. Secondary patency rates are comparable to open surgical revascularisation, with lower morbidity.


Subject(s)
Angioplasty, Balloon/instrumentation , Aorta, Abdominal , Aortic Diseases/therapy , Arterial Occlusive Diseases/therapy , Iliac Artery , Stents , Aged , Aged, 80 and over , Angiography, Digital Subtraction , Angioplasty, Balloon/adverse effects , Angioplasty, Balloon/mortality , Aorta, Abdominal/diagnostic imaging , Aorta, Abdominal/physiopathology , Aortic Diseases/diagnosis , Aortic Diseases/mortality , Aortic Diseases/physiopathology , Aortography , Arterial Occlusive Diseases/diagnosis , Arterial Occlusive Diseases/mortality , Arterial Occlusive Diseases/physiopathology , Constriction, Pathologic , Female , Humans , Iliac Artery/diagnostic imaging , Iliac Artery/physiopathology , Kaplan-Meier Estimate , Limb Salvage , Male , Middle Aged , Prosthesis Design , Recurrence , Retrospective Studies , Risk Factors , Time Factors , Treatment Outcome , Vascular Patency
18.
Pharmaceuticals (Basel) ; 6(4): 546-56, 2013 Apr 12.
Article in English | MEDLINE | ID: mdl-24276124

ABSTRACT

The effect of an allosteric modulator of the adenosine A1 receptors was investigated using an ischaemia-reperfusion protocol in murine isolated hearts. Isolated hearts were perfused with Kreb-Henseleit solution gassed with carbogen gas (95% O2 and 5% CO2) in Langendorff mode and electrically paced at 480 bpm. Following 20 min equilibration and 20 min global normothermic ischaemia, the allosteric modulator VCP333 (1 µM) or the adenosine A1 receptor partial agonist VCP102 (10 µM) were infused after 5 min of reperfusion for 15 min. Upon termination of the drug treatment, reperfusion continued for a further 40 min. At the end of 60 min reperfusion, treatment with VCP333 or VCP102 improved the recovery of the left ventricular developed pressure when compared to control group responses (p < 0.05). Neither compound affected end diastolic pressure, coronary flow rates or dP/dtmax values when compared to control tissues during reperfusion (p > 0.05). The infusion of VCP102 or VCP333 during reperfusion reduced cardiac troponin I efflux to 6.7% and 25% respectively of control heart efflux (p < 0.05). This data indicates that the allosteric modulator of the adenosine A1 receptor (VCP333) has similar characteristics to the adenosine receptor partial agonist VCP102 as it improves cardiac function and reduces myocardial cell death following an ischaemic episode.

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