Clostridioides difficile Infections: Prevention and Treatment Strategies.

Clostridioides difficile is the most common causative agent of antibiotic-associated diarrhea. This spore forming, obligate anaerobic, gram-positive bacillus is becoming responsible for an increasing number of infections worldwide, both in community and in hospital settings, whose severity can vary widely from an asymptomatic infection to a lethal disease. While discontinuation of antimicrobial agents and antibiotic treatment of the infection remain the cornerstone of therapy, more recent fecal microbiota transplantation has also been valid as a therapy. The use of probiotics, especially Saccharomyces boulardii CNCM I-745 have become valid forms of prevention therapy. Although there are studies in adults with microbiota-targeted new generation therapies and Clostridium difficile vaccines, there are no data in the paediatric age group yet.

Combined Effect of Nigella sativa and Kefir on the Live Performance and Health of Broiler Chickens Affected by Necrotic Enteritis.

Coccidiosis and necrotic enteritis (NE) are prevalent poultry ailments worldwide, leading to decreased live performance and elevated mortality rates without antibiotic usage. This study evaluated Nigella sativa (black cumin) seeds (BCS) and kefir as alternatives to antibiotics for broilers. An in vivo study over a 28-day period, using 384 Cobb 500 male broilers organized into six treatment groups as part of a completely randomized block experimental design was conducted. Each treatment group included eight replicates, with each replicate containing eight birds. The treatments included positive control, negative control, antibiotic control, 5% BCS in feed, 20% kefir in drinking water, and a combination of 5% BCS and 20% kefir. NE was induced in broilers by administering ~5000 oocysts of Eimeria maxima orally on day 14, followed by inoculation with about 108 CFU/mL of Clostridium perfringens (Cp) (strain Cp#4) on days 19, 20, and 21. Live performance metrics including feed intake, body weight gain, and feed conversion were assessed in broilers. Additionally, NE disease outcomes such as lesion scores, mortality rates, and Cp populations in cecum were determined during the study. The BCS, kefir, and the combination had no detrimental effect on broiler live performance. BCS-treated and combination groups had lower NE scores (p > 0.05) in comparison to the positive control and exhibited no significant difference (p > 0.05) from antibiotic control. Additionally, treatment groups and antibiotic control were not significantly different (p > 0.05) in mortality, whereas the BCS and kefir combination significantly reduced (p < 0.05) mortality to 14.1% compared to 31.3% for the positive control. C. perfringens vegetative cells significantly decreased (p < 0.05) in treatments with BCS, kefir, and their combination on days 22 and 28 compared to the positive control. On day 22, Cp sores were significantly lower (p < 0.05) for the kefir and combination treatments compared to the positive control. In conclusion, BCS and kefir successfully reduced C. perfringens infection and mortality without any detrimental impact on broiler live performance with the combined treatment being the most effective. These results suggest that BCS and kefir could serve as potential alternatives to antibiotics in managing NE.

Multiple Sclerosis and Clostridium perfringens Epsilon Toxin: Is There a Relationship?

Recent research has suggested a link between multiple sclerosis and the gut microbiota. This prospective pilot study aimed to investigate the composition of the gut microbiota in MS patients, the presence of Clostridium perfringens epsilon toxin in the serum of MS patients, and the influence of disease-modifying drugs (DMDs) on epsilon toxin levels and on the microbiota. Epsilon toxin levels in blood were investigated by two methods, a qualitative ELISA and a highly sensitive quantitative ELISA. Neither epsilon toxin nor antibodies against it were detected in the analyzed serum samples. 16S ribosomal RNA sequencing was applied to obtain insights into the composition of the gut microbiota of MS patients. No significant differences in the quantity, diversity, and the relative abundance of fecal microbiota were observed in the gut microbiota of MS patients receiving various DMDs, including teriflunomide, natalizumab, ocrelizumab, and fingolimod, or no therapy. The present study did not provide evidence supporting the hypothesis of a causal relationship between Clostridium perfringens epsilon toxin and multiple sclerosis.

Clostridial Myonecrosis: A Comprehensive Review of Toxin Pathophysiology and Management Strategies.

Clostridial myonecrosis, commonly known as gas gangrene (GG), is a rapidly progressing and potentially fatal bacterial infection that primarily affects muscle and soft tissue. In the United States, the incidence of GG is roughly 1000 cases per year, while, in developing countries, the incidence is higher. This condition is most often caused by Clostridium perfringens, a Gram-positive, spore-forming anaerobic bacterium widely distributed in the environment, although other Clostridium species have also been reported to cause GG. The CP genome contains over 200 transport-related genes, including ABC transporters, which facilitate the uptake of sugars, amino acids, nucleotides, and ions from the host environment. There are two main subtypes of GG: traumatic GG, resulting from injuries that introduce Clostridium spores into deep tissue, where anaerobic conditions allow for bacterial growth and toxin production, and spontaneous GG, which is rarer and often occurs in immunocompromised patients. Clostridium species produce various toxins (e.g., alpha, theta, beta) that induce specific downstream signaling changes in cellular pathways, causing apoptosis or severe, fatal immunological conditions. For example, the Clostridium perfringens alpha toxin (CPA) targets the host cell's plasma membrane, hydrolyzing sphingomyelin and phosphatidylcholine, which triggers necrosis and apoptosis. The clinical manifestations of clostridial myonecrosis vary. Some patients experience the sudden onset of severe pain, swelling, and muscle tenderness, with the infection progressing rapidly to widespread tissue necrosis, systemic toxicity, and, if untreated, death. Other patients present with discharge, pain, and features of cellulitis. The diagnosis of GG primarily involves clinical evaluation, imaging studies such as X-rays, computer tomography (CT) scans, and culture. The treatment of GG involves surgical exploration, broad-spectrum antibiotics, antitoxin, and hyperbaric oxygen therapy, which is considered an adjunctive treatment to inhibit anaerobic bacterial growth and enhance the antibiotic efficacy. Early recognition and prompt, comprehensive treatment are critical to improving the outcomes for patients affected by this severe and life-threatening condition.

Isolation of a Virulent Clostridium perfringens Strain from Elaphurus davidianus and Characterization by Whole-Genome Sequence Analysis.

Clostridium perfringens (C. perfringens) is an important veterinary pathogen and a noteworthy threat to human and animal health. Recently, there has been a significant rise in the number of moose fatalities caused by this rare, endemic species in China. Currently, there is an increasing trend in conducting whole-genome analysis of C. perfringens strains originating from pigs and chickens, whereas fewer studies have been undertaken on Elaphurus davidianus-originating strains at the whole-genome level. Our laboratory has identified and isolated five C. perfringens type A from affected Elaphurus davidianus. The current study identified the most potent strain of C. perfringens, which originated from Elaphurus davidianus, and sequenced its genome to reveal virulence genes and pathogenicity. Our findings show that strain CX1-4 exhibits the highest levels of phospholipase activity, hemolytic activity, and mouse toxicity compared to the other four isolated C. perfringens type A strains. The chromosome sequence length of the CX1-4 strain was found to be 3,355,389 bp by complete genome sequencing. The current study unveils the genomic characteristics of C. perfringens type A originating from Elaphurus davidianus. It provides a core foundation for further investigation regarding the prevention and treatment of such infectious diseases in Elaphurus davidianus.

Dietary Clostridium butyricum and 25-Hydroxyvitamin D3 modulate bone metabolism of broilers through the gut-brain axis.

Leg disorders have become increasingly common in broilers, leading to lower meat quality and major economic losses. This study evaluated the effects of dietary supplementation with Clostridium butyricum (C. butyricum) and 25-hydroxyvitamin D3 (25-OH-D3) on bone development by comparing growth performance, tibial parameters, Ca and P contents of tibial ash, bone development-related indicators' level, and cecal short-chain fatty acids in Cobb broilers. All birds were divided into four treatment groups, which birds fed either a basal diet (Con), basal diet + 75 mg chlortetracycline/kg (Anti), basal diet + C. butyricum at 109 CFU/kg (Cb), basal diet + C. butyricum at 109 CFU/kg and 25-OH-D3 at 25 µg/kg (CbD), or basal diet + 25-OH-D3 at 25 µg/kg (CD). Our results suggest that the dietary supplementation in Cb, CbD, and CD significantly increased the body weight (BW) and average daily gain (ADG), and reduced the feed-to-weight ratio (F/G) at different stages of growth (P < 0.05). Dietary supplementation in Cb, CbD, and CD prolonged (P < 0.05) the behavioral responses latency-to-lie (LTL) time, reduced (P < 0.05) the levels of osteocalcin (BGP) and peptide tyrosine (PYY), and increased (P < 0.05) serotonin (5-HT) and dopamine (DA). Treatment with Cb increased (P < 0.05) the levels of acetic acid, isobutyric acid, butyric acid, and isovaleric acid compared with those in Con group. The cecal metagenome showed that Alistipes spp. were significantly more abundant in Cb, CbD, and CD groups (P < 0.05). A total of 12 metabolic pathways were significantly affected by supplementation, including the signaling pathways of glucagon, insulin, and PI3K-AKT; primary and secondary bile acid biosynthesis; and P-type Ca 2+ transporters (P < 0.05). Hence, the CbD supplementation modulates bone metabolism by regulating the mediators of gut-brain axis, which may inform strategies to prevent leg diseases and improve meat quality in broilers.

Microbiota in lymph nodes of cattle harvested in a Canadian meat processing plant.

Lymph nodes (LN) harboring bacteria, when being incorporated into ground beef, may impact the microbial safety and quality of such products. We tested two main foodborne pathogens Salmonella and Shiga toxin-producing Escherichia coli (STEC) and profiled the microbiota in LNs (n = 160) of cattle harvested at a Canadian abattoir, by conventional plating methods, PCR, and high throughput sequencing. LNs at two anatomical locations, subiliac and popliteal from 80 cattle were included. All cattle had bacteria detected in popliteal and/or subiliac LNs with the maximum bacterial load of 5.4 and 2.8 log10CFU/g in popliteal and subiliac LNs, respectively. Neither Salmonella nor STEC was found in LNs although STEC was detected in a significant percentage of samples from beef hides (50.6 %) by plating and/or PCR. Both 16S rRNA gene amplicon and metagenome sequencing found the predominance of Escherichia (13-34.6 % among bacterial community), Clostridium (12.6-20.6 %) and Streptococcus (9.7-10 %) in popliteal LNs. Metagenomic sequencing was able to identify the predominant taxa at species level with E. coli (13 %), Clostridium perfringens (11.1 %) and Streptococcus uberis (6 %) predominant in LNs. Low prevalence/abundance of Salmonella was found by metagenomic sequencing. In conclusion, the relatively high bacterial load and diversity in LNs may affect the shelf life of ground beef and high relative abundance of E. coli would warrant further monitoring.

Epidemiology of Clostridioides difficile infection at one hospital 10 years after an outbreak of the epidemic C. difficile strain BI/027: changing strain prevalence, antimicrobial susceptibilities, and patient antibiotic exposures.

In contrast to the epidemiology 10 years earlier at our hospital when the epidemic restriction endonuclease analysis (REA) group strain BI accounted for 72% of Clostridioides difficile isolates recovered from first-episode C. difficile infection (CDI) cases, BI represented 19% of first-episode CDI isolates in 2013-2015. Two additional REA group strains accounted for 31% of isolates (Y, 16%; DH, 12%). High-level resistance to fluoroquinolones and azithromycin was more common among BI isolates than among DH, Y, and non-BI/DH/Y isolates. Multivariable analysis revealed that BI cases were 2.47 times more likely to be associated with fluoroquinolone exposure compared to non-BI cases (95% confidence interval [CI]: 1.12-5.46). In addition, the odds of developing a CDI after third- or fourth-generation cephalosporin exposure was 2.83 times for DH cases than for non-DH cases (95% CI: 1.06-7.54). Fluoroquinolone use in the hospital decreased from 2005 to 2015 from a peak of 113 to a low of 56 antimicrobial days/1,000 patient days. In contrast, cephalosporin use increased from 42 to 81 antimicrobial days/1,000 patient days. These changes correlated with a decrease in geometric mean MIC for ciprofloxacin (61.03 to 42.65 mg/L, P = 0.02) and an increase in geometric mean MIC for ceftriaxone (40.87 to 86.14 mg/L, P < 0.01) among BI isolates. The BI strain remained resistant to fluoroquinolones, but an overall decrease in fluoroquinolone use and increase in cephalosporin use were associated with a decrease in the prevalence of BI, an increased diversity of C. difficile strain types, and the emergence of strains DH and Y.

Neonatal Tetanus Still Exists: A Case Report and Review of Literature.

Neonatal tetanus (NT) remains the leading cause of death in underdeveloped countries, although it is relatively rare in developed countries. Umbilical stump sepsis in newborns born to unvaccinated mothers is a major risk factor for NT. The World Health Organization describes NT as an infection that affects infants who lose the ability to suck between 3 and 28 days of age, becoming rigid and having spasms. Limited resources in underdeveloped countries have made the management of NT difficult. In this report, we describe a fatal case of NT in a newborn born to a mother who had not received any tetanus toxoid-containing vaccine. This study aims to make neonatal health professionals aware of the symptoms of NT so that they can diagnose it early and provide the appropriate care to save lives, and stress the importance of tetanus vaccination and maintaining hygienic conditions throughout pregnancy and childbirth to prevent this disease.

Antibiotic resistance of enteropathogenic bacteria in a teaching hospital in North Khuzestan during a three-year period.

Introduction: Gastrointestinal infections affect many people annually. The most common bacterial agents involved in these infections are enteropathogenic bacteria and in the continuation of using broad-spectrum antibiotics, Clostridium difficile-associated diarrhea is involved, especially in hospitalized patients. The aim of the present study was to investigate the pattern of antibiotic resistance among enteropathogenic bacteria. Materials and Methods: In this cross-sectional study, 163 samples of patients with diarrhea in Dezful Ganjavian Hospital were examined. The samples were cultured in MacConkey, Hektoen enteric agar and GN broth, and cycloserine cefoxitin fructose agar media and incubated under standard conditions. In order to identify enteropathogenic bacteria, biochemical tests and serological confirmatory tests were used. Antibiotic resistance pattern of the isolates was investigated by Kirby-Bauer disk diffusion susceptibility test. Results: The frequency of pathogenic bacteria includes 41.1% of Shigella flexneri, followed by 41.1% of S. sonnei, 6.7% of Enteropathogenic E. coli, 5.5% of Salmonella enterica Serogroup B, and 5.5% of Shigella dysenteriae. The results revealed a total of 46 patients with orders regarding C. difficile culture, no C. difficile was isolated from the samples. The studied isolates showed the highest resistance to trimethoprim-sulfamethoxazole, and ceftriaxone (88.3%), and the most effective antibiotic in the treatment of patients was ciprofloxacin with 86% sensitivity. Conclusion: Susceptibility to antibiotics was different among the isolates, which shows that the early identification of the infection agent and the selection of the correct antibiotic treatment are effective in improving the gastrointestinal infection and preventing the spread of the infection.

Clostridium butyricum regulates intestinal barrier function via trek1 to improve behavioral abnormalities in mice with autism spectrum disorder.

BACKGROUND: Autism Spectrum Disorder (ASD) is a complex neurodevelopmental disorder that has been found to be associated with dysregulation of gastrointestinal functions and gut microbial homeostasis (the so-called "gut-brain axis"). ASD is often accompanied by poor performances in social interaction and repetitive behaviors. Studies on the gut-brain axis provide novel insights and candidate targets for ASD therapeutics and diagnosis. Based on the ASD mice model, this work aims to reveal the mechanisms behind the interaction of intestinal barrier function and probiotics in ASD mouse models. RESULTS: We found an altered intestinal barrier in both BTBR T+ Itpr3tf/J (BTBR) and valproic acid (VPA) mice, including increased intestinal permeability, decreased expression of intestinal tight junction proteins (claudin1, claudin3, and occludin), and increased levels of IL-6, TNF-α, and IFN-γ. Based on intestinal microbial alternation, C. butyricum can drive reduced expression of histone deacetylases 1 (HDAC1) and enhanced intestinal barrier function, significantly promoting behavioral abnormalities of ASD in BTBR mice. In parallel, we confirmed that C. butyricum was involved in the regulation of intestinal function by the Trek1 channel, indicating that it is a target of C. butyricum/butyric acid to improve intestinal barrier function in ASD mice. CONCLUSIONS: Our finding provides solid evidence for the gut microbiota involved in ASD through the brain-gut axis. In addition, the probiotics C. butyricum hold promise to improve gut health and ameliorate behavioral abnormalities associated with ASD.

Adjuvant Treatment with Celecoxib after Collagenase Injection for Dupuytren Contracture: A Double-Blind Randomised Controlled Trial.

Background: In patients with a high recurrence risk after treatment for Dupuytren contracture (DC) by Collagenase Clostridium histolyticum (CCH), adjuvant medical therapy may improve the outcome. Non-steroidal anti-inflammatory drugs have been used in the treatment of similar fibroproliferative processes. The aim of this study was to investigate if adjuvant anti-inflammatory medication could improve the outcome of CCH treatment for DC. Methods: In a prospective double blinded randomised trial, the effect of adjuvant peroral celecoxib on the outcome of DC treated with CCH was investigated in 32 patients with a high fibrosis diathesis. Primary outcome was the increase in Total Passive Extension Deficit (TPED)/ray. Secondary outcomes were the TPED of the individual finger joints, Tubiana index, Disability of Arm, Shoulder and Hand score (DASH) and visual analogue scale (VAS) for pain and satisfaction. Results: A significantly greater improvement in the celecoxib group for TPED and metacarpophalangeal contracture was found. For the proximal interphalangeal joint, the effect was much less pronounced. The VAS for pain and satisfaction were better at 6 and 12 weeks in the celecoxib group. The other outcome parameters did not significantly differ between both groups. Conclusions: Adjuvant peroral administration of celecoxib might improve the gain in TPED after treatment with CCH in patients with DC and a high fibrosis diathesis, with a beneficial effect up to 24 months. Level of Evidence: Level II (Therapeutic).

Encapsulation protocol for fecal microbiota transplantation.

Introduction: Clostridioides difficile infections (CDI) continue to pose a challenge for clinicians. Fecal microbiota transplantation (FMT) is an effective treatment option in CDI. Furthermore, recent and ongoing studies suggest potential benefits of FMT in other diseases as well. Methods: We would like to present a novel protocol for encapsulation of lyophilized fecal material. Our method provides with better compliance as well as improved flexibility, storage and safety. Results: FMT was conducted in 28 patients with an overall success rate of 82,14% using apsules containing lyophilized stool. 16 of patients were given capsules with lessened bacteria counts. The success rate in this group was 93,75%. Discussion: The results highlight the still unanswered questions about the mechanism of action and contribute to a wider use of FMT in the clinical praxis and in research.

Recent developments on sustainable biobutanol production: a novel integrative review.

Renewable and sustainable biofuel production, such as biobutanol, is becoming increasingly popular as a substitute for non-renewable and depleted petrol fuel. Many researchers have studied how to produce butanol cheaply by considering appropriate feedstock materials and bioprocess technologies. The production of biobutanol through acetone-butanol-ethanol (ABE) is highly sought after around the world because of its sustainable supply and lack of competition with food. The purpose of this study is to present the current biobutanol production research and to analyse the biobutanol research conducted during 2006 to 2023. The keyword used in this study is "Biobutanol," and the relevant data was extracted from the Web of Science database (WoS). According to the results, institutions and scholars from the People's Republic of China, the USA, and India have the highest number of cited papers across a broad spectrum of topics including acetone-butanol-ethanol (ABE) fermentation, biobutanol, various pretreatment techniques, and pervaporation. The success of biobutanol fermentation from biomass depends on the ability of the fermentation operation to match the microbial behaviour along with the appropriate bioprocessing strategies to improve the entire process to be suitable for industrial scale. Based on the review data, we will look at the biobutanol technologies and appropriate strategies that have been developed to improve biobutanol production from renewable biomass.

Broiler chicken distal jejunum microbial communities are more responsive to coccidiosis or necrotic enteritis challenge than dietary anti-interleukin-10 in a model using Salmonella Typhimurium- Eimeria maxima- Clostridium perfringens coinfection.

Dietary anti-interleukin (IL)-10 antibodies may protect broiler performance during coccidiosis by inhibiting Eimeria host-evasion pathways; however, anti-IL-10's effects on microbial communities during coccidiosis and secondary Clostridium perfringens (necrotic enteritis) challenge is unknown. The study objectives were to assess the jejunal microbiota of broilers fed anti-IL-10 during E. maxima ± C. perfringens challenge. Two replicate studies using Ross 308 chicks placed in wire-floor cages (32 cages/ replicate study; 20 chicks/ cage) were conducted, with chicks assigned to diets ± 0.03% anti-IL-10 for 25 d. In both replicate studies, challenge-designated chicks were inoculated with 1 × 108Salmonella Typhimurium colony forming units (CFU) at placement. On d14, S. Typhimurium-inoculated chicks were gavaged with 15,000 sporulated Eimeria maxima M6 oocysts and half the E. maxima-challenged chicks received 1×108C. perfringens CFUs on d 18 and 19. Six chicks/ treatment were euthanized for distal jejunum content collection at baseline (d 14), 7 d post-inoculation (pi) with E. maxima/ 3 dpi with C. perfringens (peak) or 11 dpi with E. maxima/ 7 dpi with C. perfringens (post-peak) for 16S rRNA gene amplicon sequencing. Sequences were quality screened (Mothur V.1.43.0) and clustered into de novo operation taxonomical units (OTU; 99% similarity) using the SILVA reference database (v138). Alpha diversity and log-transformed relative abundance data were analyzed in SAS 9.4 with replicate study, diet, challenge, and timepoint main effects plus associated interactions (P ≤ 0.05). Few baseline changes were observed, but E. maxima ± C. perfringens challenge reduced Romboutsia and Staphylococcus relative abundance 4- to 800-fold in both replicate studies (P ≤ 0.008). At peak challenge with secondary C. perfringens, feeding anti-IL-10 instead of the control diet reduced Clostridium sensu stricto 1 relative abundance 13- and 1,848-fold in both replicate studies (P < 0.0001); however, OTUs identified as C. perfringens were not affected by dietary anti-IL-10. These results indicate that anti-IL-10 does not affect the jejunal microbiota of unchallenged broilers, while coccidiosis or necrotic enteritis challenge generally contributed to greater microbiota alterations than diet.

Sequencing approaches to identify distal jejunum microbial community composition and function in broiler chickens fed anti-interleukin-10 during coccidiosis and necrotic enteritis challenge.

Strategies to counteract interleukin (IL)-10-mediated immune evasion by Eimeria spp. during coccidiosis- like anti-IL-10 antibodies- may protect broiler chicken health and reduce incidence of secondary necrotic enteritis (Clostridium perfringens) via undetermined mechanisms. Objectives were to use sequencing techniques to evaluate jejunal microbial community composition and function in anti-IL-10-fed broilers during coccidiosis and necrotic enteritis. On d0, Ross 308 chicks were placed in 32 cages (15 chicks/ cage) for a 25-d study and randomly assigned to diets ± 0.03% anti-IL-10. Six chicks/ diet were euthanized for distal jejunum content and tissue collection on d 14 (baseline) before inoculating the remainder with saline or 15,000 E. maxima oocysts (M6 strain). Half the chicks challenged with E. maxima were challenged with C. perfringens (1×108 colony forming units) on d 18 and 19. Follow-up samples (6 chicks/treatment) were collected at 7 and 11 d postinoculation (pi) for the E. maxima-only group, or 3 and 7 dpi for the E. maxima + C. perfringens group with 3/7 dpi being designated as peak and 7/11dpi as postpeak challenge. DNA was extracted from digesta for microbiota composition analysis (16S rRNA gene sequencing) while RNA was extracted from tissue to evaluate the metatranscriptome (RNA sequencing). Alpha diversity and genus relative abundances were analyzed using the diet or challenge main effects with associated interactions (SAS 9.4; P ≤ 0.05). No baseline microbial changes were associated with dietary anti-IL-10. At peak challenge, a diet main effect reduced observed species 36.7% in chicks fed anti-IL-10 vs. control; however, the challenge effect reduced observed species and Shannon diversity 51.2-58.3% and 33.0 to 35.5%, respectively, in chicks challenged with E. maxima ± C. perfringens compared to their unchallenged counterparts (P ≤ 0.05). Low sequencing depth limited metatranscriptomic analysis of jejunal microbial function via RNA sequencing. This study demonstrates that challenge impacted the broiler distal jejunum microbiota more than anti-IL-10 while future research to characterize the microbial metatranscriptome may benefit from investigating other intestinal compartments.

The Barrier Disruption and Pyroptosis of Intestinal Epithelial Cells Caused by Perfringolysin O (PFO) from Clostridium perfringens.

Clostridium perfringens (C. perfringens), a Gram-positive bacterium, produces a variety of toxins and extracellular enzymes that can lead to disease in both humans and animals. Common symptoms include abdominal swelling, diarrhea, and intestinal inflammation. Severe cases can result in complications like intestinal hemorrhage, edema, and even death. The primary toxins contributing to morbidity in C. perfringens-infected intestines are CPA, CPB, CPB2, CPE, and PFO. Amongst these, CPB, CPB2, and CPE are implicated in apoptosis development, while CPA is associated with cell death, increased intracellular ROS levels, and the release of the inflammatory factor IL-18. However, the exact mechanism by which PFO toxins exert their effects in the infected gut is still unidentified. This study demonstrates that a C. perfringens PFO toxin infection disrupts the intestinal epithelial barrier function through in vitro and in vivo models. This study emphasizes the notable influence of PFO toxins on intestinal barrier integrity in the context of C. perfringens infections. It reveals that PFO toxins increase ROS production by causing mitochondrial damage, triggering pyroptosis in IPEC-J2 cells, and consequently resulting in compromised intestinal barrier function. These results offer a scientific foundation for developing preventive and therapeutic approaches against C. perfringens infections.

Emergence of genetic diversity and multi-drug resistant Clostridium perfringens from wild birds.

BACKGROUND: Clostridium perfringens (C. perfringens) is an important zoonotic microorganism that can cause animal and human infections, however information about the prevalence status in wild birds of this pathogenic bacterium is currently limited. RESULT: In this study, 57 strains of C. perfringens were isolated from 328 fecal samples of wild birds. All the isolates were identified as type A and 70.18% of the isolates carried the cpb2 gene. Antimicrobial susceptibility testing showed that and 22.80% of the isolates were classified as multidrug-resistant strains. The MLST analysis of the 57 isolates from wild birds was categorized into 55 different sequence types (STs) and clustered into eight clonal complexes (CCs) with an average of 20.1 alleles and the Simpson Diversity index (Ds) of 0.9812, and revealed a high level of genetic diversity within the C. perfringens populations. Interestingly, the isolates from swan goose were clustered in the same CC while isolates from other bird species were more scattered suggesting that a potential difference in genetic diversity among the C. perfringens populations associated with different bird species. CONCLUSION: C. perfringens exhibits a wide range of host adaptations, varying degrees of antimicrobial resistance, and a high degree of genetic diversity in wild birds. Understanding the prevalence, toxin type, antimicrobial resistance, and genetic diversity of C. perfringens in wildlife populations is essential for developing effective strategies for disease control and management.

The first isolation of Clostridium massiliodielmoense from a dead beef cow in Japan and pitfalls to be aware of in identifying the Clostridium species.

Clostridium sp. was detected in the organs of a cow with black watery diarrhea in Japan. Results identifying this species were inconsistent; Clostridium novyi type A infection was suggested by PCR assay targeting Clostridium fliC region (fliC-multiplex PCR), while 16S rRNA gene sequencing identified the isolated bacteria as Clostridium massiliodielmoense. Sequencing of fliC-multiplex PCR products from the isolates revealed the presence of fliC region in C. massiliodielmoense, which had 92.7% nucleotide similarity to that of C. novyi type A JCM 1406T, leading to the false positive detection of C. novyi by the PCR. This is the first C. massiliodielmoense isolation from clinical specimens, suggesting the need for further research on its pathogenicity and improvement in fliC-multiplex PCR.

Ecological and evolutionary dynamics of CRISPR-Cas systems in Clostridium botulinum: Insights from genome mining and comparative analysis.

Understanding the prevalence and distribution of CRISPR-Cas systems across different strains can illuminate the ecological and evolutionary dynamics of Clostridium botulinum populations. In this study, we conducted genome mining to characterize the CRISPR-Cas systems of C. botulinum strains. Our analysis involved retrieving complete genome sequences of these strains and assessing the diversity, prevalence, and evolution of their CRISPR-Cas systems. Subsequently, we performed an analysis of homology in spacer sequences from identified CRISPR arrays to investigate and characterize the range of targeted phages and plasmids. Additionally, we investigated the evolutionary trajectory of C. botulinum strains under selective pressures from foreign invasive DNA. Our findings revealed that 306 strains possessed complete CRISPR-Cas structures, comprising 58% of the studied C. botulinum strains. Secondary structure prediction of consensus repeats indicated that subtype II-C, with longer stems compared to subtypes ID and IB, tended to form more stable RNA secondary structures. Moreover, protospacer motif analysis demonstrated that strains with subtype IB CRISPR-Cas systems exhibited 5'-CGG-3', 5'-CC-3', and 5'-CAT-3' motifs in the 3' flanking regions of protospacers. The diversity observed in CRISPR-Cas systems indicated their classification into subtypes IB, ID, II-C, III-B, and III-D. Furthermore, our results showed that systems with subtype ID and III-D frequently harbored similar spacer patterns. Moreover, analysis of spacer sequences homology with phage and prophage genomes highlighted the specific activities exhibited by subtype IB and III-B against phages and plasmids, providing valuable insights into the functional specialization within these systems.