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1.
Cell ; 185(6): 980-994.e15, 2022 03 17.
Article in English | MEDLINE | ID: mdl-35303428

ABSTRACT

The emergence of hypervirulent clade 2 Clostridioides difficile is associated with severe symptoms and accounts for >20% of global infections. TcdB is a dominant virulence factor of C. difficile, and clade 2 strains exclusively express two TcdB variants (TcdB2 and TcdB4) that use unknown receptors distinct from the classic TcdB. Here, we performed CRISPR/Cas9 screens for TcdB4 and identified tissue factor pathway inhibitor (TFPI) as its receptor. Using cryo-EM, we determined a complex structure of the full-length TcdB4 with TFPI, defining a common receptor-binding region for TcdB. Residue variations within this region divide major TcdB variants into 2 classes: one recognizes Frizzled (FZD), and the other recognizes TFPI. TFPI is highly expressed in the intestinal glands, and recombinant TFPI protects the colonic epithelium from TcdB2/4. These findings establish TFPI as a colonic crypt receptor for TcdB from clade 2 C. difficile and reveal new mechanisms for CDI pathogenesis.


Subject(s)
Bacterial Toxins , Clostridioides difficile , Bacterial Proteins/chemistry , Bacterial Toxins/chemistry , Clostridioides difficile/genetics , Lipoproteins/genetics
2.
Annu Rev Microbiol ; 74: 497-520, 2020 09 08.
Article in English | MEDLINE | ID: mdl-32680451

ABSTRACT

All bacteria must compete for growth niches and other limited environmental resources. These existential battles are waged at several levels, but one common strategy entails the transfer of growth-inhibitory protein toxins between competing cells. These antibacterial effectors are invariably encoded with immunity proteins that protect cells from intoxication by neighboring siblings. Several effector classes have been described, each designed to breach the cell envelope of target bacteria. Although effector architectures and export pathways tend to be clade specific, phylogenetically distant species often deploy closely related toxin domains. Thus, diverse competition systems are linked through a common reservoir of toxin-immunity pairs that is shared via horizontal gene transfer. These toxin-immunity protein pairs are extraordinarily diverse in sequence, and this polymorphism underpins an important mechanism of self/nonself discrimination in bacteria. This review focuses on the structures, functions, and delivery mechanisms of polymorphic toxin effectors that mediate bacterial competition.


Subject(s)
Bacteria/immunology , Bacterial Toxins/genetics , Bacterial Toxins/immunology , Gene Transfer, Horizontal , Microbial Interactions , Bacteria/genetics , Bacterial Proteins/metabolism , Bacterial Toxins/metabolism , Type VI Secretion Systems/genetics , Type VI Secretion Systems/immunology
3.
J Proteome Res ; 2024 Oct 31.
Article in English | MEDLINE | ID: mdl-39480487

ABSTRACT

The disruption of gut microbiota caused by antibiotics favors the intestinal colonization of Clostridioides difficile - a Gram-positive, spore-forming anaerobic bacterium that causes potentially fatal gastrointestinal infections. In an endeavor to elucidate the complexities of the gut-brain axis in the context of Clostridium difficile infection (CDI), a murine model has been used to investigate the potential effects of antibiotic administration and subsequent colonization by C. difficile, as well as the impact of three different 10-day treatments (metronidazole, probiotics, and fecal microbiota transplantation), on the cecal metabolome for the first time. This follows our previous research which highlighted the metabolic effect of CDI and these treatments in the brain and employs the same four different metabolomics-based methods (targeted GC-MS/MS, targeted HILIC-MS/MS, untargeted RP-LC-HRMS/MS and untargeted GC-MS). A total of 286 unique metabolites have been identified in the mouse cecal profiles and statistical analysis revealed that CDI, as well as the subsequent treatments, significantly alters cecal metabolites and lipids implicated in various biochemical pathways centered around amino acid metabolism, glycerophospholipid metabolism, and central carbon metabolism. To our knowledge, this study represents the first exploration of the effects of C. difficile-induced colitis and potential treatments on the cecal tissue metabolome.

4.
Clin Infect Dis ; 2024 Aug 24.
Article in English | MEDLINE | ID: mdl-39180326

ABSTRACT

OBJECTIVE: To evaluate the safety and efficacy of fecal microbiota, live-jslm (RBL; REBYOTA) - the first single-dose, broad consortia microbiota-based live biotherapeutic approved by the United States (US) Food and Drug Administration for preventing recurrent Clostridioides difficile infection (rCDI) in adults following standard-of-care (SOC) antibiotic treatment. DESIGN: PUNCH CD3-OLS was a prospective, phase 3, open-label study, conducted across the US and Canada. Participants were aged ≥18 years with documented rCDI and confirmed use of SOC antibiotics. Participants with comorbidities including inflammatory bowel disease and mild-to-moderate immunocompromising conditions could be enrolled. A single dose of RBL was rectally administered within 24-72h of antibiotic completion. The primary endpoint was the number of participants with RBL- or administration-related treatment-emergent adverse events (TEAEs). Secondary endpoints included treatment success and sustained clinical response, at 8 weeks and 6 months after RBL administration, respectively. RESULTS: Overall, 793 participants were enrolled, of whom 697 received RBL. TEAEs through 8 weeks after administration were reported by 47.3% of participants; most events were mild or moderate gastrointestinal disorders. Serious TEAEs were reported by 3.9% of participants. The treatment success rate at 8 weeks was 73.8%; in participants who achieved treatment success, the sustained clinical response rate at 6 months was 91.0%. Safety and efficacy rates were similar across demographic and baseline characteristic subgroups. CONCLUSIONS: RBL was safe and efficacious in participants with rCDI and common comorbidities. This is the largest microbiota-based live biotherapeutic study to date and findings support use of RBL to prevent rCDI in a broad patient population. CLINICAL TRIAL REGISTRATION: The study is registered at ClinicalTrials.gov (NCT03931941).

5.
Article in English | MEDLINE | ID: mdl-38871148

ABSTRACT

BACKGROUND & AIMS: Clostridioides difficile infection (CDI) is associated with high mortality. Fecal microbiota transplantation (FMT) is an established treatment for recurrent CDI, but its use for first or second CDI remains experimental. We aimed to investigate the effectiveness of FMT for first or second CDI in a real-world clinical setting. METHODS: This multi-site Danish cohort study included patients with first or second CDI treated with FMT from June 2019 to February 2023. The primary outcome was cure of C. difficile-associated diarrhea (CDAD) 8 weeks after the last FMT treatment. Secondary outcomes included CDAD cure 1 and 8 weeks after the first FMT treatment and 90-day mortality following positive C. difficile test. RESULTS: We included 467 patients, with 187 (40%) having their first CDI. The median patient age was 73 years (interquartile range [IQR], 58-82 years). Notably, 167 (36%) had antibiotic-refractory CDI, 262 (56%) had severe CDI, and 89 (19%) suffered from fulminant CDI. Following the first FMT treatment, cure of CDAD was achieved in 353 patients (76%; 95% confidence interval [CI], 71%-79%) at week 1. At week 8, 255 patients (55%; 95% CI, 50%-59%) maintained sustained effect. In patients without initial effect, repeated FMT treatments led to an overall cure of CDAD in 367 patients (79%; 95% CI, 75%-82%). The 90-day mortality was 10% (95% CI, 8%-14%). CONCLUSION: Repeated FMT treatments demonstrate high effectiveness in managing patients with first or second CDI. Forwarding FMT in CDI treatment guidelines could improve patient survival. CLINICALTRIALS: gov, Number: NCT03712722.

6.
Small ; 20(37): e2401374, 2024 Sep.
Article in English | MEDLINE | ID: mdl-38659396

ABSTRACT

The removal of uranyl ions (UO2 2+) from water is challenging due to their chemical stability, low concentrations, complex water matrix, and technical limitations in extraction and separation. Herein, a novel molybdenum disulfide/graphene oxide heterojunction (MoS2/GO-H) is developed, serving as an effective electrode for capacitive deionization (CDI). By combining the inherent advantages of electroadsorption and electrocatalysis, an innovative electroadsorption-electrocatalysis system (EES) strategy is introduced. This system utilizes interface polarization at the MoS2 and GO interface, creating an additional electric field that significantly influences carrier behavior. The MoS2/GO-H electrode, with its extraordinary adsorption capacity of 805.57 mg g-1 under optimal conditions, effectively treated uranium-laden wastewater from a mine, achieving over 90% removal efficiency despite the presence of numerous competing ions at concentrations significantly higher than UO2 2+. Employing density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulations, it is found that the MoS2/GO-H total charge density at the Fermi level, enhanced by interfacial polarization, surpasses that of separate MoS2 and GO, markedly boosting conductivity and electrocatalytic effectiveness.

7.
Eur J Clin Microbiol Infect Dis ; 43(4): 785-789, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38332395

ABSTRACT

Clostridioides difficile is a leading cause of healthcare-associated infections. The main objective was to assess the current landscape of CDI infection prevention and control (IPC) practices. An anonymous survey of IPC practices for CDI was conducted between July 25 and October 31, 2022. Precautions for symptomatic patients were applicable for 75.9% and were discontinued 48 h minimum after the resolution of diarrhea for 40.7% of respondents. Daily cleaning of CDI patients' rooms was reported by 23 (42.6%). There was unexpected heterogeneity in IPC practices regarding the hospital management of CDI.


Subject(s)
Clostridioides difficile , Clostridium Infections , Cross Infection , Humans , Clostridioides , Cross Infection/prevention & control , Diarrhea/prevention & control , Health Facilities , Clostridium Infections/prevention & control
8.
Environ Sci Technol ; 58(29): 13120-13130, 2024 Jul 23.
Article in English | MEDLINE | ID: mdl-38985512

ABSTRACT

While flow-electrode capacitive deionization (FCDI) is recognized as an attractive desalination technology, its practical implementation has been hindered by the ease of scaling and energy-intensive nature of the single-cell FCDI system, particularly when treating brackish water with elevated levels of naturally coexisting SO42- and Ca2+. To overcome these obstacles, we propose and design an innovative ion-selective metathesis FCDI (ISM-FCDI) system, consisting of a two-stage tailored cell design. Results indicate that the specific energy consumption per unit volume of water for the ISM-FCDI is lower (by up to ∼50%) than that of a conventional single-stage FCDI due to the parallel circuit structure of the ISM-FCDI. Additionally, the ISM-FCDI benefits from a conspicuous disparity in the selective removal of ions at each stage. The separate storage of Ca2+ and SO42- by the metathesis process in the ISM-FCDI (46.25% Ca2+, 14.25% SO42- in electrode 1 and 4.75% Ca2+, 35.25% SO42- in electrode 2) can effectively prevent scaling. Furthermore, configuration-performance analysis on the ion-selective migration suggests that the properties of the ion exchange membrane, rather than the carbon species, govern the selectivity of ion removal. This work introduces system-level enhancements aimed at enhancing energy conservation and scaling prevention, providing critical optimization of the FCDI for brackish water softening.


Subject(s)
Electrodes , Saline Waters , Water Purification , Water Purification/methods , Saline Waters/chemistry , Ions , Water Softening
9.
Ann Clin Microbiol Antimicrob ; 23(1): 35, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38664689

ABSTRACT

PURPOSE: The clinical significance of negative toxin enzyme immunoassays (EIA) for Clostridioides difficile infections (CDIs) is unclear. Our study aimed to investigate the significance of toxin EIA-negative in the diagnosis and prognosis of CDI. METHODS: All stool specimens submitted for C. difficile toxin EIA testing were cultured to isolate C. difficile. In-house PCR for tcdA, tcdB, cdtA, and cdtB genes were performed using C. difficile isolates. Stool specimens were tested with C. difficile toxins A and B using EIA kit (RIDASCREEN Clostridium difficile toxin A/B, R-Biopharm AG, Darmstadt, Germany). Characteristics and subsequent CDI episodes of toxin EIA-negative and -positive patients were compared. RESULTS: Among 190 C. difficile PCR-positive patients, 83 (43.7%) were toxin EIA-negative. Multivariate analysis revealed independent associations toxin EIA-negative results and shorter hospital stays (OR = 0.98, 95% CI 0.96-0.99, p = 0.013) and less high-risk antibiotic exposure in the preceding month (OR = 0.38, 95% CI 0.16-0.94, p = 0.035). Toxin EIA-negative patients displayed a significantly lower white blood cell count rate (11.0 vs. 35.4%, p < 0.001). Among the 54 patients who were toxin EIA-negative and did not receive CDI treatment, three (5.6%) were diagnosed with CDI after 7-21 days without complication. CONCLUSION: Our study demonstrates that toxin EIA-negative patients had milder laboratory findings and no complications, despite not receiving treatment. Prolonged hospitalisation and exposure to high-risk antibiotics could potentially serve as markers for the development of toxin EIA-positive CDI.


Subject(s)
Bacterial Proteins , Bacterial Toxins , Clostridioides difficile , Clostridium Infections , Feces , Humans , Clostridioides difficile/genetics , Feces/microbiology , Male , Female , Bacterial Toxins/analysis , Clostridium Infections/diagnosis , Clostridium Infections/drug therapy , Clostridium Infections/microbiology , Aged , Middle Aged , Bacterial Proteins/genetics , Bacterial Proteins/analysis , Enterotoxins/analysis , Aged, 80 and over , Anti-Bacterial Agents/therapeutic use , Immunoenzyme Techniques , Adult , Treatment Outcome , Polymerase Chain Reaction , Prognosis
10.
BMC Public Health ; 24(1): 1118, 2024 Apr 23.
Article in English | MEDLINE | ID: mdl-38654267

ABSTRACT

BACKGROUND: Many adolescents experience depression that often goes undetected and untreated. Identifying children and adolescents at a high risk of depression in a timely manner is an urgent concern. While the Children's Depression Inventory (CDI) is widely utilized in China, it lacks a localized revision or simplified version. With its 27 items requiring professional administration, the original CDI proves to be a time-consuming method for predicting children and adolescents with high depression risk. Hence, this study aimed to develop a shortened version of the CDI to predict high depression risk, thereby enhancing the efficiency of prediction and intervention. METHODS: Initially, backward elimination is conducted to identify various version of the short-form scales (e.g., three-item and five-item versions). Subsequently, the performance of five machine learning (ML) algorithms on these versions is evaluated using the area under the ROC curve (AUC) to determine the best algorithm. The chosen algorithm is then utilized to model the short-form scales, facilitating the identification of the optimal short-form scale based on predefined evaluation metrics. Following this, evaluation metrics are computed for all potential decision thresholds of the optimal short-form scale, and the threshold value is determined. Finally, the reliability and validity of the optimal short-form scale are assessed using a new sample. RESULTS: The study identified a five-item short-form CDI with a decision threshold of 4 as the most appropriate scale considering all assessment indicators. The scale had 81.48% fewer items than the original version, indicating good predictive performance (AUC = 0.81, Accuracy = 0.83, Recall = 0.76, Precision = 0.71). Based on the test of 315 middle school students, the results showed that the five-item CDI had good measurement indexes (Cronbach's alpha = 0.72, criterion-related validity = 0.77). CONCLUSIONS: This five-item short-form CDI is the first shortened and revised version of the CDI in China based on large local data samples.


Subject(s)
Depression , Machine Learning , Humans , Adolescent , Child , Female , Male , China , Depression/diagnosis , Reproducibility of Results , Psychiatric Status Rating Scales/standards , Psychometrics , Algorithms
11.
Adv Exp Med Biol ; 1435: 57-84, 2024.
Article in English | MEDLINE | ID: mdl-38175471

ABSTRACT

Clostridioides difficile infection (CDI) remains a significant cause of morbidity and mortality worldwide. Historically, two antibiotics (metronidazole and vancomycin) and a recent third (fidaxomicin) have been used for CDI treatment; convincing data are now available showing that metronidazole is the least efficacious agent. The European Society of Clinical Microbiology and Infectious Diseases (ESCMID) management guidance for CDI were updated in 2021. This guidance document outlines the treatment options for a variety of CDI clinical scenarios and for non-antimicrobial management (e.g., faecal microbiota transplantation, FMT). One of the main changes is that metronidazole is no longer recommended as first-line CDI treatment. Rather, fidaxomicin is preferred on the basis of reduced recurrence rates with vancomycin as an acceptable alternative. Recommended options for recurrent CDI now include bezlotoxumab as well as FMT.A 2017 survey of 20 European countries highlighted variation internationally in CDI management strategies. A variety of restrictions were in place in 65% countries prior to use of new anti-CDI treatments, including committee/infection specialist approval or economic review/restrictions. This survey was repeated in November 2022 to assess the current landscape of CDI management practices in Europe. Of 64 respondents from 17 countries, national CDI guidelines existed in 14 countries, and 11 have already/plan to incorporate the ESCMID 2021 CDI guidance, though implementation has not been surveyed in 6. Vancomycin is the most commonly used first-line agent for the treatment of CDI (n = 42, 66%), followed by fidaxomicin (n = 30, 47%). Six (9%) respondents use metronidazole as first-line agent for CDI treatment, whereas 22 (34%) only in selected low-risk patient groups. Fidaxomicin is more likely to be used in high-risk patient groups. Availability of anti-CDI therapy influenced prescribing in six respondents (9%). Approval pre-prescription was required before vancomycin (n = 3, 5%), fidaxomicin (n = 10, 6%), bezlotoxumab (n = 11, 17%) and FMT (n = 10, 6%). Implementation of CDI guidelines is rarely audited.Novel anti-CDI agents are being evaluated; it is not yet clear what will be the roles of these agents. The treatment of recurrent CDI is particularly troublesome, and several different live biotherapeutics are being developed, in addition to FMT.


Subject(s)
Clostridium Infections , Metronidazole , Humans , Fidaxomicin , Vancomycin , Anti-Bacterial Agents/therapeutic use , Clostridium Infections/drug therapy
12.
Adv Exp Med Biol ; 1435: 85-99, 2024.
Article in English | MEDLINE | ID: mdl-38175472

ABSTRACT

Clostridioides difficile infection (CDI) is one of the most common healthcare-associated infections and one of the leading causes of morbidity and mortality in hospitalized patients in the world. Although several antibiotics effectively treat CDI, some individuals may not respond to these drugs and may be cured by transplanting stool from healthy donors. FMT has demonstrated extraordinary cure rates for the cure of CDI recurrences.Moreover, FMT has also been investigated in other disorders associated with the alteration of gut microbiota, such as inflammatory bowel disease (IBD), where the alterations of the gut microbiota ecology have been theorized to play a causative role. Although FMT is currently not recommended to cure IBD patients in clinical practice, several studies have been recently carried out with the ultimate goal to search new therapeutic options to patients.This review summarizes data on the use of FMT for the treatment of both CDI and IBD, with a special attention to highlight studies conducted in European countries.


Subject(s)
Cross Infection , Inflammatory Bowel Diseases , Humans , Fecal Microbiota Transplantation , Feces , Anti-Bacterial Agents , Inflammatory Bowel Diseases/therapy
13.
Proc Natl Acad Sci U S A ; 118(40)2021 10 05.
Article in English | MEDLINE | ID: mdl-34599102

ABSTRACT

Listeriolysin S (LLS) is a thiazole/oxazole-modified microcin (TOMM) produced by hypervirulent clones of Listeria monocytogenes LLS targets specific gram-positive bacteria and modulates the host intestinal microbiota composition. To characterize the mechanism of LLS transfer to target bacteria and its bactericidal function, we first investigated its subcellular distribution in LLS-producer bacteria. Using subcellular fractionation assays, transmission electron microscopy, and single-molecule superresolution microscopy, we identified that LLS remains associated with the bacterial cell membrane and cytoplasm and is not secreted to the bacterial extracellular space. Only living LLS-producer bacteria (and not purified LLS-positive bacterial membranes) display bactericidal activity. Applying transwell coculture systems and microfluidic-coupled microscopy, we determined that LLS requires direct contact between LLS-producer and -target bacteria in order to display bactericidal activity, and thus behaves as a contact-dependent bacteriocin. Contact-dependent exposure to LLS leads to permeabilization/depolarization of the target bacterial cell membrane and adenosine triphosphate (ATP) release. Additionally, we show that lipoteichoic acids (LTAs) can interact with LLS and that LTA decorations influence bacterial susceptibility to LLS. Overall, our results suggest that LLS is a TOMM that displays a contact-dependent inhibition mechanism.


Subject(s)
Bacteriocins/metabolism , Cell Membrane/metabolism , Hemolysin Proteins/metabolism , Listeria monocytogenes/metabolism , Adenosine Triphosphate/metabolism , Cytoplasm/metabolism
14.
Euro Surveill ; 29(6)2024 Feb.
Article in English | MEDLINE | ID: mdl-38333935

ABSTRACT

BackgroundCommunity-associated Clostridioides difficile infections (CA-CDI) have increased worldwide. Patients with CDI-related symptoms occurring < 48 hours after hospitalisation and no inpatient stay 12 weeks prior are classified as CA-CDI, regardless of hospital day attendances 3 months before CDI onset. Healthcare-associated (HA) CDIs include those with symptom onset ≥ 48 hours post hospitalisation.AimTo consider an incubation period more reflective of CDI, and changing healthcare utilisation, we measured how varying surveillance specifications to categorise patients according to their CDI origin resulted in changes in patients' distribution among CDI origin categories.MethodsNew CDI cases between 2012-2021 from our hospital were reviewed. For patients with CA-CDI, hospital day attendances in the 3 months prior were recorded. CA-CDI patients with hospital day attendances and recently discharged CDI patients (RD-CDI; CDI onset 4-12 weeks after discharge) were combined into a new 'healthcare-exposure' category (HE-CDI). Time from hospitalisation to disease onset was varied and the midpoint between optimal and balanced cut-offs was used instead of 48 hours to categorise HA-CDI.ResultsOf 1,047 patients, 801 (76%) were HA-CDI, 205 (20%) CA-CDI and 41 (4%) were RD-CDI. Of the CA-CDI cohort, 45 (22%) met recent HE-CDI criteria and, when reassigned, reduced CA-CDI to 15%. Sensitivity analysis indicated a day 4 cut-off for assigning HA-CDI. Applying this led to 46 HA-CDI reassigned as CA-CDI. Applying both HE and day 4 criteria led to 72% HA-CDI, 20% CA-CDI, and 8% HE-CDI (previously RD-CDI).ConclusionCDI surveillance specifications reflecting healthcare exposure and an incubation period more characteristic of C. difficile may improve targeted CDI prevention interventions.


Subject(s)
Clostridioides difficile , Clostridium Infections , Community-Acquired Infections , Cross Infection , Humans , Community-Acquired Infections/epidemiology , Ireland/epidemiology , Clostridium Infections/diagnosis , Clostridium Infections/epidemiology , Cross Infection/epidemiology , Cross Infection/diagnosis , Tertiary Care Centers , Delivery of Health Care , Patient Acceptance of Health Care , Referral and Consultation
15.
Anaerobe ; 90: 102917, 2024 Oct 10.
Article in English | MEDLINE | ID: mdl-39393610

ABSTRACT

INTRODUCTION: In the past decade, the incidence of community-acquired Clostridioides difficile infection (CA-CDI) has increased, suggesting a role for community reservoirs such as animals in its spread. OBJECTIVE: This study aimed to isolate and characterize C. difficile strains from domestic dogs at veterinary clinics to enhance our understanding of C. difficile epidemiology in Rio de Janeiro. MATERIAL AND METHODS: For this study 90 stool samples from dogs were collected and cultured in a selective medium (Clostridioides difficile Brucella agar - CDBA) for isolation. Species were identified by MALDI-TOF MS, with confirmation provided by PCR targeting the tpi gene. The antibiotic susceptibility test of the strains was performed using five antibiotics: vancomycin, metronidazole, moxifloxacin, rifampicin, and erythromycin. Strains resistant to metronidazole were further analyzed for the presence of the plasmid pCD-METRO using PCR. The presence of toxin genes (tcdA, tcdB, and cdtB) was investigated, alongside ribotyping and tcdC sequencing analyses. The strains were also tested for biofilm formation and motility. RESULTS: C. difficile was isolated in 15.5 % (14/90) of the samples. Among the strains analyzed, 87.71 % (12/14) tested positive for both toxin genes tcdA and tcdB and belonged to ribotypes 106 (10/14) and 014/020 (2/14). The remaining 14.3 % (2/14) were non-toxigenic and were identified as ribotype 010. Regarding the antibiotic profile, 42.85 % (6/14) of the strains exhibited resistance to at least one antibiotic, including vancomycin (1/14) and metronidazole (1/14). The metronidazole-resistant strain was also positive for the plasmid pCD-METRO. All strains exhibited both biofilm formation and motility. Among the 12 toxigenic strains sequenced for the tcdC gene, two exhibited a deletion in the same region as the epidemic strain, NAP1 (RT027). CONCLUSION: Our study found some overlap between C. difficile ribotypes isolated from dogs and from cases of CDI in humans, and the C. difficile prevalence was higher in dogs with diarrhea (p = 0.034).

16.
Anaerobe ; 89: 102896, 2024 Oct.
Article in English | MEDLINE | ID: mdl-39127403

ABSTRACT

INTRODUCTION: Clostridioides difficile is the main cause of antibiotic-associated diarrhea in humans and is a major enteropathogen in several animal species. In newborn piglets, colonic lesions caused by C. difficile A and B toxins (TcdA and TcdB, respectively) cause diarrhea and significant production losses. OBJECTIVE: The present study aimed to develop two recombinant vaccines from immunogenic C-terminal fragments of TcdA and TcdB and evaluate the immune response in rabbits and in breeding sows. Two vaccines were produced: bivalent (rAB), consisting of recombinant fragments of TcdA and TcdB, and chimeric (rQAB), corresponding to the synthesis of the same fragments in a single protein. Groups of rabbits were inoculated with 10 or 50 µg of proteins adjuvanted with aluminum or 0.85 % sterile saline in a final volume of 1 mL/dose. Anti-TcdA and anti-TcdB IgG antibodies were detected in rabbits and sows immunized with both rAB and rQAB vaccines by ELISA. The vaccinated sows were inoculated intramuscularly with 20 µg/dose using a prime-boost approach. RESULTS: Different antibody titers (p ≤ 0.05) were observed among the vaccinated groups of sows (rAB and rQAB) and control. Additionally, newborn piglets from vaccinated sows were also positive for anti-TcdA and anti-TcdB IgGs, in contrast to control piglets (p ≤ 0.05). Immunization of sows with the rQAB vaccine conferred higher anti-TcdA and anti-TcdB responses in piglets, suggesting the superiority of this compound over rAB. CONCLUSION: The synthesized recombinant proteins were capable of inducing antibody titers against C. difficile toxins A and B in sows, and were passively transferred to piglets through colostrum.


Subject(s)
Animals, Newborn , Antibodies, Bacterial , Bacterial Toxins , Bacterial Vaccines , Clostridioides difficile , Clostridium Infections , Swine Diseases , Vaccines, Synthetic , Animals , Female , Swine , Rabbits , Clostridium Infections/prevention & control , Clostridium Infections/veterinary , Clostridium Infections/immunology , Bacterial Vaccines/immunology , Bacterial Vaccines/administration & dosage , Bacterial Vaccines/genetics , Pregnancy , Vaccines, Synthetic/immunology , Vaccines, Synthetic/administration & dosage , Clostridioides difficile/immunology , Clostridioides difficile/genetics , Antibodies, Bacterial/blood , Bacterial Toxins/immunology , Bacterial Toxins/genetics , Swine Diseases/prevention & control , Swine Diseases/immunology , Bacterial Proteins/immunology , Bacterial Proteins/genetics , Enterotoxins/immunology , Enterotoxins/genetics
17.
Anaerobe ; 86: 102836, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38428802

ABSTRACT

OBJECTIVES: The aim was to assess the impact of the SARS-CoV-2 pandemic on the prevalence, relative incidence (RI), incidence density (ID), ratio of rate incidence (RRI), rate of incidence density (RID), and relative risks (RR) of healthcare-onset Clostridioides difficile infection (HO-CDI) as well as its correlation with the antibiotic consumption. METHODS: Demographic and analytical data of adult patients exhibiting diarrhoea and testing positive for C. difficile were systematically collected from a tertiary care hospital in Madrid (Spain). The periods analysed included: prepandemic (P0), first pandemic-year (P1), and second pandemic-year (P2). We compared global prevalence, RI of HO-CDI per 1,000-admissions, ID of HO-CDI per 10,000-patients-days, RRI, RID, and RR. Antibiotic consumption was obtained by number of defined daily dose per 100 patient-days. RESULTS: In P0, the prevalence of HO-CDI was 7.4% (IC95%: 6.2-8.7); in P1, it increased to 8.7% (IC95%: 7.4-10.1) (p = 0.2), and in P2, it continued to increase to 9.2% (IC95%: 8-10.6) (p < 0.05). During P1, the RRI was 1.5 and RID was 1.4. However, during P2 there was an increase in RRI to 1.6 and RID to 1.6. The RR also reflected the increase in HO-CDI: at P1, the probability of developing HO-CDI was 1.5 times (IC95%: 1.2-1.9) higher than P0, while at P2, this probability increased to 1.6 times (IC95%: 1.3-2.1). There was an increase in prevalence, RI, ID, RR, RRI, and RID during the two postpandemic periods respect to the prepandemic period. During P2, this increase was greater than the P1. Meropenem showed a statistically significant difference increased consumption (p < 0.05) during the pandemic period. Oral vancomycin HO-CDI treatment showed an increase during the period of study (p > 0.05). CONCLUSIONS: Implementation of infection control measures during the SARS-CoV-2 pandemic did not appear to alleviate the burden of HO-CDI. The escalation in HO-CDI cases did not exhibit a correlation with overall antibiotic consumption, except for meropenem.


Subject(s)
COVID-19 , Clostridioides difficile , Clostridium Infections , Cross Infection , Tertiary Care Centers , Clostridioides difficile/genetics , Clostridioides difficile/isolation & purification , Clostridium Infections/diagnosis , Clostridium Infections/epidemiology , Clostridium Infections/microbiology , Humans , COVID-19/epidemiology , Diarrhea/epidemiology , Vancomycin/administration & dosage , Cross Infection/diagnosis , Cross Infection/epidemiology , Cross Infection/microbiology , Spain/epidemiology , Retrospective Studies , Incidence , Disease Outbreaks , Prevalence , Anti-Bacterial Agents/administration & dosage , Risk , Pandemics/statistics & numerical data , Infection Control/statistics & numerical data , Meropenem/administration & dosage , Middle Aged , Aged , Aged, 80 and over
18.
Anaerobe ; 87: 102842, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38552897

ABSTRACT

Late anti-toxin-B humoral immunity acquired after treatment is important for preventing recurrent Clostridioides difficile infection. We prospectively-measured anti-toxin-B IgG and neutralization titers at diagnosis as potential early predictors of recurrence. High anti-toxin-B-IgG/neutralizing antibodies were associated with short-lasting protection within 6-weeks, however, no difference in recurrence risk was observed by 90-days post-infection.


Subject(s)
Antibodies, Bacterial , Bacterial Toxins , Clostridioides difficile , Clostridium Infections , Immunoglobulin G , Recurrence , Clostridium Infections/immunology , Clostridium Infections/prevention & control , Humans , Immunoglobulin G/blood , Immunoglobulin G/immunology , Bacterial Toxins/immunology , Clostridioides difficile/immunology , Antibodies, Bacterial/blood , Antibodies, Bacterial/immunology , Male , Middle Aged , Female , Aged , Bacterial Proteins/immunology , Prospective Studies , Antibodies, Neutralizing/immunology , Antibodies, Neutralizing/blood , Adult , Aged, 80 and over
19.
J Environ Manage ; 353: 120133, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38308985

ABSTRACT

Enhanced phytoextraction of metal-polluted soils using EDTA is phasing out in favor of biodegradable chelants. However, these are too short-lived to be effective in the acclimated biodegrading soil environment established in long-term phytoextraction operations. We hypothesize that full-scale EDTA-enhanced phytoextraction can be both effective and environmentally safe, provided that soil leaching is prevented while EDTA persists in the soil profile. This was tested for 4 years in two sealed, well-monitored constructed lagoons (70-m3 each) packed with Cd-contaminated dredged sediment. Fast-growing, high-biomass, salinity-resistant eucalypts were planted in June 2010. Under controlled deficit irrigation, the 3-year average EC was 14.2 dS m-1. Summer leakage accounted for ∼1.2 % of the overall irrigation water and was prescribed for monitoring the composition of the soil solution. Altogether, 486 leachate and 261 suction-cap solutions were collected at average intervals of 5.5 days. EDTA was intermittently applied with summer irrigation, in multiple low doses at average seasonal concentrations of 1.1-9.2 mM. The soil solution EDTA biodegraded quickly after those applications were stopped. This cessation was timed well before the start of the rainy season. Spontaneous EDTA leaching during the three winters accounted for <0.02 % of the total 423 mol/basin applied. Prescribed summer leaching constituted ∼1 % of this total. Peak heavy metal (HM) concentrations in the leachate and suction-cap solutions (e.g., Cd, up to 18.5 and 14 mg L-1, respectively) were observed soon after EDTA application. Winter HM concentrations were not significantly different from the background. As the amounts of EDTA diminished, HM also disappeared from the soil solution, probably by adsorption. Eucalyptus occidentalis was by far the most efficient Cd sink of the five species tested,. The results of this study strongly support our hypothesis that EDTA-enhanced phytoextraction can be both effective and environmentally safe.


Subject(s)
Metals, Heavy , Soil Pollutants , Edetic Acid , Cadmium , Soil Pollutants/analysis , Biodegradation, Environmental , Metals, Heavy/analysis , Soil , Chelating Agents
20.
Molecules ; 29(20)2024 Oct 18.
Article in English | MEDLINE | ID: mdl-39459302

ABSTRACT

Porous carbon with a high surface area and controllable pore size is needed for energy storage. It is still a significant challenge to produce porous carbon in an economical way. Nitrogen-doped porous carbon (N-PC) was prepared through carbonization of a mixture of waste PET-derived metal-organic frameworks (MOFs) and ammonium. The obtained N-PC exhibits a large surface area and controlled pore size. When utilized as an electrode material for supercapacitors, the N-PC exhibits a specific capacitance of 224 F g-1, significantly surpassing that of commercial activated carbon (AC), which has a capacitance of 111 F g-1. In the subsequent capacitive deionization (CDI) tests, the N-PC demonstrated a maximum salt adsorption capacity of 19.9 mg g-1 at 1.2 V in a NaCl electrolyte (0.5 g L-1), and the salt adsorption capacity increased to 24.7 mg g-1 at 1.4 V. The N-PC electrode also exhibited superior regeneration. The present work not only presents a potential approach to develop cost-effective electrodes for seawater purification but also paves the way for recycling of waste plastics into high value-added products.

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