Molecular Characterization and Antimicrobial Susceptibilities of Corynebacterium pseudotuberculosis Isolated from Caseous Lymphadenitis of Smallholder Sheep and Goats.

Caseous lymphadenitis (CLA) is a bacterial infection caused by Corynebacterium pseudotuberculosis (C. pseudotuberculosis) that affects sheep and goats, leading to abscess formation in their lymph nodes. The present study aimed to isolate and identify C. pseudotuberculosis from CLA in smallholder sheep and goats, and determine the resistance patterns, virulence, and resistance genes of the isolates. Additionally, genotypic and phylogenetic analysis of the isolates was conducted using ERIC-PCR and DNA sequencing techniques. A cross-sectional study examined 220 animals (130 sheep and 90 goats) from 39 smallholder flocks for clinical signs of CLA. Fifty-four (24.54%) animals showed CLA-compatible lesions, confirmed by C. pseudotuberculosis isolation and PCR identification. Sheep had a lower infection rate of CLA (18.46%) compared with goats (33.3%). Antimicrobial susceptibility testing of 54 C. pseudotuberculosis isolates to 24 antimicrobial drugs revealed that they were 100% resistant to bacitracin and florfenicol, while none of the isolates were resistant to norfloxacin. A high resistance rate was observed for penicillin and erythromycin (92.6% each). Interestingly, 16.7% of C. pseudotuberculosis isolates recovered from sheep showed vancomycin resistance. Molecular characterization of C. pseudotuberculosis isolates revealed that PLD, PIP, and FagA virulence genes were present in all examined isolates. However, the FagB, FagC, and FagD genes were detected in 24 (100%), 20 (83%), and 18 (75%) of the sheep isolates, and 26 (87%), 26 (87%), and 18 (60%) of the goat isolates, respectively. The ß-lactam resistance gene was present in all isolates. Furthermore, 83% of the sheep isolates carried the aminoglycoside (aph(3″)-lb), chloramphenicol (cat1), and bacitracin (bcrA) resistance genes. Among the isolates recovered from goats, 73% were found to contain macrolides (ermX), sulfonamide (sul1), and bacitracin (bcrA) resistance genes. It is worrisome that the glycopeptide (vanA) resistance gene was detected in 8% of the sheep isolates as a first report. ERIC-PCR genotyping of 10 multi-drug-resistant C. pseudotuberculosis isolates showed a high similarity index of 83.6% between isolates from sheep and goats. Nucleotide sequence analysis of partial 16S rRNA sequences of C. pseudotuberculosis revealed 98.83% similarity with biovar Ovis of globally available reference sequences on the Genbank database. Overall, our findings might indicate that C. pseudotuberculosis infection in smallholders in Egypt might be underestimated despite the significant financial impact on animal husbandry and potential health hazards it poses. Moreover, this study highlights the importance of implementing a sustainable control strategy and increasing knowledge and awareness among smallholder breeders to mitigate the economic impact of CLA.

Influence of biosynthesized nanoparticles exposure on mortality, residual deposition, and intestinal bacterial dysbiosis in Cyprinus carpio.

Nanotechnology has revealed profound possibilities for the applications in applied sciences. The nanotechnology works based on nanoparticles. Among nanoparticles, silver nanoparticles largely introduced into aquatic environments during fabrication. Which cause severe contamination in the environment specially in freshwater fish. Therefore, the current study was a pioneer attempt to use the animal blood to fabricate AgNPs and investigate their toxicity in Cyprinus carpio (C. carpio) by recording mortality, tissue bioaccumulation, and influence on intestinal bacterial diversity. For this purpose, fish groups were exposed to different concentrations of B-AgNPs including 0.03, 0.06, and 0.09 mg/L beside the control group for 1, 10, and 20 days. Initially, the highest concentration caused mortality. The results revealed that B-AgNPs were significantly (p < 0.005) accumulated in the liver followed by intestines, gills, and muscles. In addition, the accumulation of B-AgNPs in the intestine led to bacterial dysbiosis in Cyprinus carpio. At the phylum level, Tenericutes, Bacteroidetes, and Planctomycetes were gradually decreased at the highest concentration of B-AgNPs (0.09 mg/L) on days 1, 10, and 20 days. The genera Cetobacterium and Luteolibactor were increased at the highest concentration on day 20. Moreover, the principal coordinate analysis (PCoA) based on Bray-Curtis showed that the B-AgNPs had led to a variation in the intestinal bacterial community. Based on findings, the B-AgNPs induced mortality, and residual deposition in different tissues, and had a stress influence on intestinal homeostasis by affecting the intestinal bacterial community in C. carpio which could have a significant effect on fish growth.

Clostridium perfringens Associated with Foodborne Infections of Animal Origins: Insights into Prevalence, Antimicrobial Resistance, Toxin Genes Profiles, and Toxinotypes.

Several food-poisoning outbreaks have been attributed to Clostridium perfringens (C. perfringens) worldwide. Despite that, this crisis was discussed in a few studies, and additional studies are urgently needed in this field. Therefore, we sought to highlight the prevalence, antimicrobial resistance, toxin profiles, and toxinotypes of C. perfringens isolates. In this study, 50 C. perfringens isolates obtained from 450 different animal origin samples (beef, chicken meat, and raw milk) were identified by phenotypic and genotypic methods. The antimicrobial susceptibility results were surprising, as most of the isolates (74%) showed multidrug-resistant (MDR) patterns. The phenotypic resistance to tetracycline, lincomycin, enrofloxacin, cefoxitin/ampicillin, and erythromycin was confirmed by the PCR detections of tet, lnu, qnr, bla, and erm(B) genes, respectively. In contrast to the toxinotypes C and E, toxinotype A prevailed (54%) among our isolates. Additionally, we found that the genes for C. perfringens enterotoxin (cpe) and C. perfringens beta2 toxin (cpb2) were distributed among the tested isolates with high prevalence rates (70 and 64%, respectively). Our findings confirmed that the C. perfringens foodborne crisis has been worsened by the evolution of MDR strains, which became the prominent phenotypes. Furthermore, we were not able to obtain a fixed association between the toxinotypes and antimicrobial resistance patterns.

Genetic Relatedness, Antibiotic Resistance, and Effect of Silver Nanoparticle on Biofilm Formation by Clostridium perfringens Isolated from Chickens, Pigeons, Camels, and Human Consumers.

In this study, we determined the prevalence and toxin types of antibiotic-resistant Clostridium perfringens in chicken, pigeons, camels, and humans. We investigated the inhibitory effects of AgNPs on biofilm formation ability of the isolates and the genetic relatedness of the isolates from various sources determined using RAPD-PCR. Fifty isolates were identified using PCR, and all the isolates were of type A. The cpe and cpb2 genes were detected in 12% and 56% of the isolates, respectively. The effect of AgNPs on biofilm production of six representative isolates indicated that at the highest concentration of AgNPs (100 µg/mL), the inhibition percentages were 80.8-82.8%. The RAPD-PCR patterns of the 50 C. perfringens isolates from various sources revealed 33 profiles and four clusters, and the discriminatory power of RAPD-PCR was high. Multidrug-resistant C. perfringens isolates are predominant in the study area. The inhibition of biofilm formation by C. perfringens isolates was dose-dependent, and RAPD-PCR is a promising method for studying the genetic relatedness between the isolates from various sources. This is the first report of AgNPs' anti-biofilm activity against C. perfringens from chickens, pigeons, camels, and humans, to the best of our knowledge.

Mooseer (Allium hirtifolium) boosts growth, general health status, and resistance of rainbow trout (Oncorhynchus mykiss) against Streptococcus iniae infection.

In large-scale aquaculture, the fast growth rate of fish is positively influenced by feed additives such as medicinal plants. This is however; infectious disease may reduce fish growth and cause devastating economic loss. The present study investigated in vitro antibacterial efficacy of Mooseer (Allium hirtifolium) extract against Streptococcus iniae and its in vivo effects on growth, biochemical parameters, innate immunity of rainbow trout (Oncorhynchus mykiss). Therefore, six experimental diets were designed to include different levels of Mooseer from zero (as control), 5, 10, 15, 20, and 25 g per kg diet respectively referred to as M1 to M5. Results from the antibacterial evaluation showed that Mooseer extract inhibits S. iniae growth with MIC and MBC values of 128 and 256 µg ml-1. Appreciable results were obtained in the groups supplemented with Mooseer. Mooseer enhanced growth performance, and modulated serum biochemical and immunological parameters (total protein, albumin, triglyceride, glucose, cortisol, cholesterol, lysozyme, Ig, ACH50, ALP, and protease activity), and liver enzymes (ALT, AST and ALP). The greatest effects were found for higher doses of Mooseer supplementation (M4 and M5). Meanwhile, results from the survival rate of fish challenged with S. iniae showed higher survival in M2 and M4 treatments. The present findings suggest the beneficial use of Mooseer in rainbow trout diet, with 20 g kg-1 inclusion as the recommended dose.

Antimicrobial and antibiofilm potentials of cinnamon oil and silver nanoparticles against Streptococcus agalactiae isolated from bovine mastitis: new avenues for countering resistance.

BACKGROUND: Streptococcus agalactiae (S. agalactiae) is a contagious pathogen of bovine mastitis. It has financial implications for the dairy cattle industry in certain areas of the world. Since antimicrobial resistance increases in dairy farms, natural antimicrobials from herbal origins and nanoparticles have been given more attention as an alternative therapy. Hence, this study reported the antimicrobial and antibiofilm potentials of cinnamon oil, silver nanoparticles (AgNPs), and their combination against multidrug-resistant (MDR) S. agalactiae recovered from clinical bovine mastitis in Egypt. RESULTS: Our findings revealed that 73% (146/200) of the examined milk samples collected from dairy cows with clinical mastitis were infected with Streptococci species. Of these, 9.59% (14/146) were identified as S. agalactiae and categorized as MDR. S. agalactiae isolates expressed four virulence genes (Hyl, cylE, scpB, and lmb) and demonstrated an ability to produce biofilms. Cinnamon oil showed high antimicrobial (MICs ≤0.063 µg /mL) and antibiofilm (MBIC50 = 4 µg/mL) potentials against planktonic and biofilms of S. agalactiae isolates, respectively. However, AgNPs showed reasonable antimicrobial (MICs ≤16 µg/mL) and relatively low antibiofilm (MBIC50 = 64 µg/mL) activities against screened isolates. Synergistic antimicrobial or additive antibiofilm interactions of cinnamon oil combined with AgNPs were reported for the first time. Scanning electron microscope (SEM) analysis revealed that biofilms of S. agalactiae isolates treated with cinnamon oil were more seriously damaged than observed in AgNPs cinnamon oil combination. Moreover, reverse transcriptase quantitative polymerase chain reaction (RT-qPCR) showed that cinnamon oil exerted a remarkable down-regulation of pili biosynthesis genes (pilA and pilB) and their regulator (rogB) against S. agalactiae biofilms, meanwhile the AgNPs cinnamon oil combination demonstrated a lower efficacy. CONCLUSIONS: This is an in vitro preliminary approach that documented the antibiofilm potential of cinnamon oil and the inhibitory activity of cinnamon oil and its combination with AgNPs against MDR S. agalactiae recovered from clinical mastitis. Further in vivo studies should be carried out in animal models to provide evidence of concept for implementing these alternative candidates in the treatment of dairy farms infected by streptococcal mastitis in the future.

Drug Repurposing: Dipeptidyl Peptidase IV (DPP4) Inhibitors as Potential Agents to Treat SARS-CoV-2 (2019-nCoV) Infection.

The current outbreak of severe acute respiratory distress syndrome (SARS) or nCOVID-19 pandemic, caused by the coronavirus-2 (CoV-2), continues to wreak havoc globally. As novel vaccines are being discovered and developed, small molecule drugs still constitute a viable treatment option for SARS-CoV-2 infections due to their advantages such as superior patient compliance for oral therapies, reduced manufacturing costs and ease of large scale distribution due to better stability and storage profiles. Discovering new drugs for SARS-CoV-2 infections is a time consuming and expensive proposition. In this regard, drug repurposing is an appealing approach which can provide rapid access to therapeutics with proven record of safety and efficacy. We investigated the drug repurposing potential of a library of dipeptidyl peptidase 4 (DPP4) inhibitors which are currently marketed for type-2 diabetes as treatment option for SARS-CoV-2 infections. These computational studies led to the identification of three marketed DPP4 inhibitors; gemigliptin, linagliptin and evogliptin as potential inhibitors of SARS-CoV-2 Mpro viral cysteine protease. In addition, our computational modeling shows that these drugs have the potential to inhibit other viral cysteine proteases from the beta coronavirus family, including the SAR-CoV Mpro and MERS-CoV CLpro suggesting their potential to be repurposed as broad-spectrum antiviral agents.

Efflux Pump Inhibitors, Alpha-Tocopherol and Aspirin: Role in Campylobacter jejuni and Campylobacter coli Fluoroquinolone Resistance.

This study aimed to investigate how efflux pump activity contributes to high fluoroquinolone (FQ) resistance in Campylobacter jejuni and Campylobacter coli isolates and to evaluate the modulatory effects of α-tocopherol and aspirin on FQ phenotypic resistance profiles. Minimum inhibitory concentration (MIC) values were obtained for different FQ agents following exposure to different efflux pump inhibitors (EPIs), including PaßN (50 µg/mL), which targets the cmeABC efflux system, and chlorpromazine (45 µg/mL) and verapamil (120 µg/mL), which target the MFS efflux system. The modulatory effects of aspirin (100 and 200 µg/mL) and α-tocopherol (4 and 10 µg/mL) on FQ resistance profiles were examined. PaßN had no effect on the MIC values of all FQ agents, while MFS efflux system inhibitors reduced the resistance level of different FQ agents and achieved an effect nearly comparable with that of α-tocopherol (10 µg/mL). Aspirin exerted a dose-dependent excitatory effect on phenotypic resistance profiles, and this may raise concerns about its usage in both veterinary and clinical settings. While an efflux system other than cmeABC may play a role in FQ resistance in Campylobacter species, lipophilic substances may represent a new approach for controlling efflux pump activities.

Anti-inflammatory indomethacin analogs endowed with preferential COX-2 inhibitory activity.

Aim: The undeniable indomethacin potency has always suffered serious obstacles such as gastric damage. Continuous attempts to develop potent yet safe indomethacin analogs have never ceased. Results: Herein are new indole derivatives 4a-h and 5a-c, which were synthesized via Fisher indole reaction, evaluated for both their in vivo anti-inflammatory activities using rat paw edema method and their in vitro cyclooxygenase inhibitory activities. Then ulcerogenic liability, physicochemical parameters and molecular docking modeling were performed for the most potent ones. Conclusion: Promising results were obtained, where compound 4f was the best anti-inflammatory agent and preferential COX-2/COX-1 inhibitor (90.5% edema inhibition, selective index = 65.71, ulcer index = 7.3), if compared with indomethacin (86.7% edema inhibition, selective index = 0.079, ulcer index = 20.20).

ERIC-PCR Genotyping of Some Campylobacter jejuni Isolates of Chicken and Human Origin in Egypt.

The public health importance of the genus Campylobacter is attributed to several species causing diarrhea in consumers. Poultry and their meat are considered the most important sources of human campylobacteriosis. In this study, 287 samples from chicken (131 cloacal swabs, 39 chicken skin, 78 chicken meat, and 39 cecal parts) obtained from retail outlets as well as 246 stool swabs from gastroenteritis patients were examined. A representative number of the biochemically identified Campylobacter jejuni isolates were identified by real-time PCR, confirming the identification of the isolates as C. jejuni. Genotyping of the examined isolates (n = 31) by enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) revealed a high discriminatory index of ERIC-PCR (D = 0.948), dividing C. jejuni isolates of chicken and human origins into 18 profiles and four clusters. The 18 profiles obtained indicated the heterogeneity of C. jejuni. Dendrogram analysis showed that four clusters were generated; all human isolates fell into clusters I and III. These observations further support the existence of a genetic relationship between human and poultry isolates examined in the present study. In conclusion, the results obtained support the speculation that poultry and poultry meat have an important role as sources of infection in the acquisition of Campylobacter infection in humans.