Emergence and Genomic Characterization of a spa Type t4407 ST6-SCCmec Type IVa Methicillin-Resistant Staphylococcus aureus Strain Isolated from Al-Karak Hospital, Jordan.

Background and Objectives: Methicillin-resistant Staphylococcus aureus (MRSA) is a major concern in Jordanian hospitals in terms of infection control. The purpose of this study was to identify the resistance patterns of Staphylococcus aureus strains isolated from surfaces of critical locations within the Al-Karak Governmental Hospital in 2019. Additionally, the study aimed to conduct whole-genome sequencing on the isolates. Materials and Methods: In February 2019, fourteen S. aureus strains were isolated from surfaces in critical sites in the Al-Karak Governmental Hospital. These isolates underwent antibiogram testing to determine their resistance profile. Genome sequencing using the Illumina MiSeq platform was applied to the extracted DNA from these isolates. The genomic data, including coding sequences, were analyzed to identify lineage, resistance genes, and plasmids. Results: The antibiogram results revealed that 11 of the 14 isolates were resistant to oxacillin, 6 to linezolid, and 1 to rifampicin, while none showed resistance to chloramphenicol. Eleven isolates were identified as MRSA, with a novel spa type (t4407) not previously reported in Jordan. High-quality sequencing data were obtained for only one isolate, i.e., A29, the genome showed 2,789,641 bp with a 32.7% GC content and contained 2650 coding sequences. Genomic analysis indicated the ST6 lineage, mecA gene (SCCmec type IVa(2B)), and a hybrid plasmid (pJOR_blaZ) carrying the blaZ gene for ß-lactam resistance. Genomic data were deposited in NCBI (CP104989). The A29 genome closely resembled an MRSA genome isolated from a Danish hospital in 2011. The SNP analysis revealed identical antimicrobial resistance genes in these two genomes. Conclusions: This study unveils the first genomic sequence of an MRSA isolate from Jordan, marked by distinctive genotypic traits. The findings enhance our understanding of the MRSA types circulating in Jordan and the region and substantiate the phenomenon of intercontinental MRSA transmission.

Protective role of iron oxide nanocomposites on disease index, and biochemical resistance indicators against Fusarium oxysporum induced-cucumber wilt disease: In vitro, and in vivo studies.

Recently nanocomposites have become a super-growth inducers as well as vital antifungal agents, which enhance plant growth and suppress plant diseases. A new strategy regarding the fabrication of humic acid (H) and boron (B) conjugated Fe2O3 nanocomposites was performed. Fe2O3 NP-B and Fe2O3 NP-H were synthesized in the presence of gamma-rays (as a direct reducing agent). Gamma-rays provoked reduction of metal ions due to the liberated reducing electrons, (e-aq), in aqueous solutions which can be considered as a direct reduction. Antifungal potential against Fusarium oxysporum, the causative agent of wilt disease in cucumber was determined. Disease index percent, metabolic resistance indicators in cucumber plant as response to promotion of systemic resistance (SR) were recorded. Results illustrated that both Fe2O3 NPs-B and Fe2O3 NPs-H nanocomposites had antifungal activity against F. oxysporumin vitro as well as in vivo. Results revealed that minimum inhibitory concentrations of Fe2O3 NPs-B and Fe2O3 NPs-H nanocomposites were 0.25 and 0.125 mM, respectively. Application of Fe2O3 NPs-B (0.25 mM) and Fe2O3 NPs-H (0.125 mM) appeared highly reduced the cucumber wilt disease symptoms incidence caused by F. oxysporum, and recorded disease severity by 83.33%. Fe2O3 NPs-B was the best treatment reducing disease indexes by 20.83% and gave highly protection against wilt disease by 75.0% and came next Fe2O3 NPs-H which reduced disease indexes by 25% and gave 69.99% protection against disease. Fe2O3 NPs-B and Fe2O3 NPs-H treatments improved morphological traits, photosynthetic pigments, osmolytes, total phenol and antioxidant enzymes activities in both infected and non-infected plants. The beneficial effects of the synthesized Fe2O3 NPs-B and Fe2O3 NPs-H nanocomposites were extended to increase not only the total phenol, and total soluble protein contents but also the activities of peroxidase (POD), and polyphenol oxidase (PPO) enzymes of the healthy and infected cucumber plants in comparison with control.

Mathematical pharmacodynamic modeling for antimicrobial assessment of ceftazidime/colistin versus gentamicin/meropenem combinations against carbapenem-resistant Pseudomonas aeruginosa biofilm.

BACKGROUND: Carbapenem-resistant Pseudomonas aeruginosa (CRPA) represents an escalating healthcare hazard with high mortality worldwide, especially in presence of biofilm. The current study aimed to evaluate the anti-biofilm potentials of ceftazidime, colistin, gentamicin, and meropenem alone and in combinations against biofilm-forming CRPA. METHODS: Biofilm killing and checkerboard assay were performed to detect the effectiveness of combined antibiotics against biofilms and planktonic cells, respectively. The bacterial bioburden retrieved from the established biofilms following treatment with combined antibiotics was utilized to construct a three-dimensional response surface plot. A sigmoidal maximum effect model was applied to determine the pharmacodynamic parameters (maximal effect, median effective concentration, and Hill factor) of each antibiotic to create a mathematical three-dimensional response surface plot. RESULTS: Data revealed statistically significant (p < 0.05) superior anti-biofilm potential in the case of colistin followed by a lower effect in the case of gentamicin and meropenem, while ceftazidime exhibited the least anti-biofilm activity. The fractional inhibitory concentration index (FICI ≤ 0.5) indicated synergism following treatment with the combined antibiotics. An elevated anti-biofilm activity was recorded in the case of gentamicin/meropenem compared to ceftazidime/colistin. Synergistic anti-biofilm potentials were also detected via the simulated pharmacodynamic modeling, with higher anti-biofilm activity in the case of the in vitro observation compared to the simulated anti-biofilm profile. CONCLUSIONS: The present study highlighted the synergistic potentials of the tested antibiotic combinations against P. aeruginosa biofilms and the importance of the mathematical pharmacodynamic modeling in investigating the efficacy of antibiotics in combination as an effective strategy for successful antibiotic therapy to tackle the extensively growing resistance to the currently available antibiotics.

Modulating the transcriptomic profile of multidrug-resistant Klebsiella pneumoniae biofilm formation by antibiotics in combination with zinc sulfate.

BACKGROUND: Klebsiella pneumoniae is a significant healthcare-associated pathogen. We investigated the antimicrobial interaction pattern between zinc sulfate and antibiotics against K. pneumoniae biofilm on the phenotypic and genotypic levels. METHODS: Determining the minimum biofilm inhibitory concentrations and the transcriptomic profile of K. pneumoniae biofilm formation genes post-treatment were carried out to evaluate the effect on the phenotypic and genotypic levels, respectively. RESULTS: Zinc enhanced the antibiofilm potentials of cephalosporins, aminoglycosides, and ertapenem, whereas it antagonizes the effectiveness of fluoroquinolones and meropenem on the phenotypic level. On the molecular level, zinc enhanced the anti-biofilm efficacies of cephalosporins (cefotaxime, ceftriaxone, ceftazidime, cefpirome, and cefepime) via down-regulating the expression of biofilm-related genes by 18-, 38-, 5-, 77- and 2-folds, respectively. Zinc in combination with aminoglycosides (kanamycin, gentamicin, and amikacin) reduced the expression of biofilm-related genes by 40-, 2602- and 20-folds, respectively, and by 2-folds in combination with ertapenem. However, a reduction in the down-regulatory potentials of fluoroquinolones was recorded following combination with zinc by 2-, 2-, 15- and 14-folds, respectively, and an up-regulation in the expression levels of the tested genes by 2-folds in the case of zinc/meropenem combination. CONCLUSIONS: Results revealed variable interaction patterns between different antibiotics in combination with zinc. Current findings also shed light on the antibiofilm potentials of zinc/antibiotics combinations especially when combining zinc with fluoroquinolones or meropenem to avoid their antagonistic effects.

Promising advances in nanobiotic-based formulations for drug specific targeting against multidrug-resistant microbes and biofilm-associated infections.

Antimicrobial agents and alternative strategies to combat bacterial infections have become urgent due to the rapid development of multidrug-resistant bacteria caused by the misuse and overuse of antibiotics, as well as the ineffectiveness of antibiotics against difficult-to-treat infectious diseases. Nanobiotics is one of the strategies being explored to counter the increase in antibiotic-resistant bacteria. Nanobiotics are antibiotic molecules encapsulated in nanoparticles or artificially engineered pure antibiotics that are ≤ 100 nm in size in at least one dimension. Formulation scientists recognize nanobiotic delivery systems as an effective strategy to overcome the limitations associated with conventional antibiotic therapy. This review highlights the general mechanisms by which nanobiotics can be used to target resistant microbes and biofilm-associated infections. We focus on the design elements, properties, characterization, and toxicity assessment of organic nanoparticles, inorganic nanoparticle and molecularly imprinted polymer-based nano-formulations that can be designed to improve the efficacy of nanobiotic formulation.

Combination therapy between prophylactic and therapeutic human papillomavirus (HPV) vaccines with special emphasis on implementation of nanotechnology.

Human papillomavirus (HPV) is the most prevalent sexually transmitted disease in the world. Even though preventive vaccines against HPV are effective, the effective treatment of HPV infections is much less satisfactory due to multi-drug resistance and secondary adverse effects. Nanotechnology was employed for the delivery of anti-cancer drugs to increase the effectiveness of the treatment and minimize the side effects. Nanodelivery of both preventive and therapeutic HPV vaccines has also been studied to boost vaccine efficacy. Overall, such developments suggest that the nanoparticle-based vaccine might emerge as the most cost-effective way to prevent and treat HPV cancer, assisted or combined with another nanotechnology-based therapy. This review focuses on the current knowledge on pathogenesis and vaccines against HPV, highlighting the current value and perspective regarding the widespread diffusion of HPV vaccines-based nanomaterials. The ongoing advancements in the design of vaccines-based nanomaterials are expanding their therapeutic roles against HPV.

Narrative review on century of respiratory pandemics from Spanish flu to COVID-19 and impact of nanotechnology on COVID-19 diagnosis and immune system boosting.

The rise of the highly lethal severe acute respiratory syndrome-2 (SARS-2) as corona virus 2019 (COVID-19) reminded us of the history of other pandemics that happened in the last century (Spanish flu) and stayed in the current century, which include Severe-Acute-Respiratory-Syndrome (SARS), Middle-East-Respiratory-Syndrome (MERS), Corona Virus 2019 (COVID-19). We review in this report the newest findings and data on the origin of pandemic respiratory viral diseases, reservoirs, and transmission modes. We analyzed viral adaption needed for host switch and determinants of pathogenicity, causative factors of pandemic viruses, and symptoms and clinical manifestations. After that, we concluded the host factors associated with pandemics morbidity and mortality (immune responses and immunopathology, ages, and effect of pandemics on pregnancy). Additionally, we focused on the burdens of COVID-19, non-pharmaceutical interventions (quarantine, mass gatherings, facemasks, and hygiene), and medical interventions (antiviral therapies and vaccines). Finally, we investigated the nanotechnology between COVID-19 analysis and immune system boosting (Nanoparticles (NPs), antimicrobial NPs as antivirals and immune cytokines). This review presents insights about using nanomaterials to treat COVID-19, improve the bioavailability of the abused drugs, diminish their toxicity, and improve their performance.

The antibacterial effect and the incidence of post-operative pain after the application of nano-based intracanal medications during endodontic retreatment: a randomized controlled clinical trial.

OBJECTIVE: This clinical trial aimed to evaluate the effect of nano-silver and nano-calcium hydroxide intracanal medicaments (ICM) during retreatment regarding their antibacterial effect and their effect on post-operative pain and flare-ups. MATERIALS AND METHODS: Sixty-nine patients scheduled for endodontic retreatment were included in this randomized clinical trial and randomly allocated to 3 equal groups (n = 23) according to the type of ICM used. The first microbial sampling (S1) representing the original microbiota was obtained after the removal of the old canal filling. After chemo-mechanical debridement, another sample (S2) was obtained representing the microbial state before ICM application. Patients were randomly allocated to receive either nano-silver (nano-Ag), nano-calcium hydroxide (nano-CH), or calcium hydroxide (CH) as ICM. Patients rated their pain pre-operatively and then after 6, 12, 24, 48, and 72 h. During the second visit (7 days later), the last microbial sample (S3) was obtained after removal of the ICM. Reduction of total bacterial and total E. faecalis counts and the biofilm-forming capability of the existing microbiota were determined. RESULTS: Results showed reduction in total bacterial count, total E. faecalis count and the biofilm-forming,capability of the existing microbiota after chemo-mechanical debridement (S1-S2) and after the application of ICM (S3-S2). However, the reduction after cleaning and shaping was significantly more pronounced (p < 0.001) compared to the effect of ICM application, with no difference between the 3 ICM (p > 0.05). Post-operative pain was significantly reduced at the 48- and 72-h intervals after the application of nano-Ag and nano-CH only (p < 0.001), with no significant difference between these two ICM (p > 0.05). The incidence of flare-ups in all groups was similar (p > 0.05). CONCLUSIONS: The antibacterial effect of the nano-Ag and nano-CH was equivalent to that of CH, but they contributed to better pain control. CLINICAL RELEVANCE: Nanoparticles may have a positive impact on post-endodontic pain.

Effect of scopoletin on phagocytic activity of U937-derived human macrophages: Insights from transcriptomic analysis.

Scopoletin is a botanical coumarin. Notably, scopoletin effect on phagocytic activity has not been addressed on transcriptomic level. Accordingly, this study investigated the effect of scopoletin on phagocytosis-linked gene transcription. Whole phagocytosis transcriptional profiling of stimulated U937-derived macrophages (SUDMs) in response to scopoletin as compared to non-treated SUDMs was studied. Regarding scopoletin effect on 92 phagocytosis-linked genes, 12 of them were significantly affected (p-value < .05). Seven genes were downregulated (CDC42, FCGR1A/FCGR1C, ITGA9, ITGB3, PLCE1, RHOD & RND3) and five were upregulated (DIRAS3, ITGA1, PIK3CA, PIK3R3 & PLCD1). Moreover, scopoletin enhanced phagocytic activity of SUDMs. The current results highlighted the potential use of scopoletin as immunity booster and as an adjuvant remedy in management of some autoimmune reactions. To the best of our knowledge, this is the first report that unravels the effect of scopoletin on phagocytosis via transcriptomic analysis.

Persisters of Klebsiella pneumoniae and Proteus mirabilis: A Common Phenomenon and Different Behavior Profiles.

Persisters of infectious agents are capable of surviving antibiotic treatment so the emergence of these subpopulations need to be overcome. In this study, we aimed to isolate, characterize and inhibit persister subpopulation in two clinical isolates Klebsiella pneumoniae and Proteus mirabilis. Different behavior profiles between the two isolates could be observed. The results of dose-dependent killing curve revealed that 2.3% (Klebsiella pneumoniae) versus 1.3% (Proteus mirabilis) persister cells could be recovered using 500 and 30 ug/ml ciprofloxacin, respectively. Upon resuscitation, persister cells exhibited only 65% versus 30% percentage growth and 5 versus 7 times cell elongation relative to Klebsiella pneumoniae and Proteus mirabilis, respectively. The levels of persister cells to ciprofloxacin of Klebsiella pneumoniae were dramatically decreased by about 79, 92, 97 and 83% in average by pre-exposure to hyperosmotic stress, temperature, different pHs, and hydrogen peroxide, respectively, while those of Proteus mirabilis were minimally decreased with corresponding reduction percentages of about 12%, 24 & 25%, and 0%. Regarding combating persisters, Klebsiella pneumoniae showed different response as compared to Proteus mirabilis. Among the tested sugars, the highest reduction of Klebsiella pneumoniae persister cells was obtained with pre-priming with sucrose while for Proteus mirabilis persister cells, the highest reduction was obtained with pre-priming with glucose. Using sodium salicylate with ciprofloxacin could eradicate persisters of Klebsiella pneumoniae at any tested concentration while for Proteus mirabilis it caused some reduction in persister cells at certain concentrations. Complete eradication of persisters was obtained by combining silver nitrate with ciprofloxacin for each test isolate.

Correlation between antifungal resistance and virulence factors in Candida albicans recovered from vaginal specimens.

Candida albicans is considered as the leading species causing vulvovaginal candidiasis. Numerous virulence determinants and escalating resistance to antifungal therapy have contributed to its pathogenicity. However, correlation between resistance profiles and virulence patterns of C. albicans is not very well-investigated, which was the main focus of the current study. C. albicans isolates (n = 65) were recovered from vaginal swab specimens and identified to the species level. Antifungal susceptibilities of isolates were performed against (amphotericin B, nystatin, clotrimazole, fluconazole, voriconazole, and micafungin), and their minimum inhibitory concentrations (MICs) were determined according to Clinical and Laboratory Standards Institute (CLSI) guidelines. Virulence patterns including secreted hydrolases (phospholipase, aspartyl protease, and haemolysin), cell surface hydrophobicity, and biofilm production were evaluated. Associations between resistance profiles and virulence patterns of tested C. albicans isolates were analyzed. Isolates showed variable levels of resistance and virulence patterns. Furthermore, there are significant (p < 0.05) positive correlations between amphotericin B MICs and biofilm production. However, significant (p < 0.05) negative correlations are found between fluconazole and voriconazole MICs and cell surface hydrophobicity as well as biofilm production. Moreover, significant (p < 0.05) negative correlations are detected between voriconazole MICs and aspartyl protease production. This study revealed significant correlations between resistance profiles and virulence patterns of C. albicans isolates recovered from vulvovaginal specimens.

Influence of subinhibitory antifungal concentrations on extracellular hydrolases and biofilm production by Candida albicans recovered from Egyptian patients.

BACKGROUND: Extracellular hydrolases (phospholipase, aspartyl protease and haemolysin) and biofilm production are considered as major virulence factors of the opportunistic pathogenic fungus Candida albicans. However, the impact of antifungal therapy on such virulence attributes is not well investigated. The common antifungal agents may disturb the production of secreted hydrolases as well as biofilm formation. Accordingly, this study addressed the effect of subinhibitory concentrations (sub-MICs) of selected antifungal agents on some virulence factors of C. albicans clinical isolates. METHODS: C. albicans isolates (n = 32) were recovered from different clinical samples and their identification was confirmed to the species level. Antifungal susceptibility profiles of isolates were determined against (nystatin, fluconazole and micafungin) and minimum inhibitory concentrations (MICs) were interpreted according to Clinical and Laboratory Standards Institute guidelines. Virulence determinants comprising secreted hydrolases (phospholipase, aspartyl protease and haemolysin) and biofilm formation were investigated in the presence of the sub-MICs of the tested antifungal agents. RESULTS: Treatment of clinical C. albicans isolates with subinhibitory nystatin, fluconazole and micafungin concentrations significantly decreased production of extracellular hydrolases. Nystatin had the greatest inhibitory effect on phospholipase and aspartyl protease production. However, micafungin showed the highest reducing effect on the hemolytic activity of the treated clinical isolates. Moreover, nystatin and micafungin, but not fluconazole, had a noticeable significant impact on inhibiting biofilm formation of C. albicans clinical isolates. CONCLUSION: Our findings highlighted the significant influences of commonly prescribed antifungal agents on some virulence factors of C. albicans. Accordingly, antifungal therapy may modulate key virulence attributes of C. albicans.

Isolation and characterization of mercury-resistant bacteria from wastewater sources in Egypt.

An important mechanism for microbial resistance to mercury is its reduction into elemental mercury (facilitated by the merA gene). Thirty-eight microbial isolates from a variety of wastewater sources in Egypt were collected. Approximately 14 of the 38 isolates exhibited not only a high degree of tolerance to mercury (up to 160 ppm) but also a high degree of resistance to other tested heavy metals (Cu, Co, Ni, and Zn). From these 14, the 10 most resistant isolates were selected for further study and were found to include 9 Gram-negative and 1 Gram-positive bacterial strains. Multi-antibiotic-resistance profiles were detected for 6 out of the 10 selected isolates. All the tested Gram-negative isolates (n = 9) harbored a plasmid-encoded merA gene. The mercury removal effectiveness for the 10 selected isolates ranged between 50% and 99.9%, among which Stenotrophomonas maltophilia ADW10 recorded the highest rate (99.9%; at an initial mercury concentration of 20 ppm). To the best of our knowledge, this is the first study to (i) demonstrate the presence of a multimetal-resistant S. maltophilia bacterium with a high mercury tolerance capacity that would make it a suitable candidate for future bioremediation efforts in heavy-metal-polluted areas in Egypt and (ii) report Pseudomonas otitidis as one of the mercury-resistant bacteria.

Overexpressed recombinant quorum quenching lactonase reduces the virulence, motility and biofilm formation of multidrug-resistant Pseudomonas aeruginosa clinical isolates.

The increasing occurrence of resistance among Pseudomonas aeruginosa clinical isolates necessitates finding alternatives to antibiotics for controlling the infection of such pathogenic bacteria. In this study, lactonase gene ahl-1 from Bacillus weihenstephanensis isolate-P65 was successfully cloned and expressed in Escherichia coli BL21 (DE3) under the control of T7 promoter for utilizing its quorum quenching activity against three multidrug-resistant (MDR) P. aeruginosa clinical isolates. The biological activity of the overexpressed lactonase enzyme (Ahl-1), tested using a synthetic signal and Chromobacterium violaceum CV026 as a biosensor, displayed good catalytic activity using hexanoyl homoserine lactone (HHL) as a substrate and Chromobacterium violaceum (CV026) as a biosensor (77.2 and 133 nm min-1 for the crude and the purified Ahl-lactonase enzymes, respectively). Upon challenging its ability to inhibit the virulence of three MDR P. aeruginosa clinical isolates, recombinant Ahl-1 successfully prevented the accumulation of acylhomoserine lactone signals resulting in a significant reduction in the investigated virulence determinants; protease (from 40 up to 75.5%), pyocyanin (48-75.9%), and rhamnolipids (52.7-63.4%) (P value < 0.05). Ahl-1 also displayed significant inhibitory activities on the swarming motility and biofilm formation of the three tested MDR P. aeruginosa clinical isolates (P value < 0.05). Consequently, Ahl-1 lactonase enzyme in this study is considered a promising therapeutic agent to inhibit P. aeruginosa pathogenicity with no fear of emergence of resistance.

Genetic diversity of Shiga toxin-producing Escherichia coli O157 : H7 recovered from human and food sources.

The aim of this study was to identify an epidemiological association between Shiga toxin-producing Escherichia coli O157 : H7 strains associated with human infection and with food sources. Frequency distributions of different genetic markers of E. coli O157 : H7 strains recovered from human and food sources were compared using molecular assays to identify E. coli O157 : H7 genotypes associated with variation in pathogenic potential and host specificity. Genotypic characterization included: lineage-specific polymorphism assay (LSPA-6), clade typing, tir (A255T) polymorphism, Shiga toxin-encoding bacteriophage insertion site analysis and variant analysis of Shiga toxin 2 gene (stx2a and stx2c) and antiterminator Q genes (Q933 and Q21). The intermediate lineage (LI/II) dominated among both food and human strains. Compared to other clades, clades 7 and 8 were more frequent among food and human strains, respectively. The tir (255T) polymorphism occurred more frequently among human strains than food strains. Q21 and Q933 + Q21 were found at significantly higher frequencies among food and human strains, respectively. Moreover, stx2a and stx2a+c were detected at significantly higher frequencies among human strains compared to food strains. Bivariate analysis revealed significant concordance (P<0.05) between the LSPA-6 assay and the other typing methods. Multivariable regression analysis suggested that tir (255T) was the most distinctive genotype that can be used to detect bacterial clones with potential risk for human illness from food sources. This study supported previous reports of the existence of diversity in genetic markers among different isolation sources by including E. coli O157 : H7 strains from both food and human sources. This might enable tracking genotypes with potential risk for human illness from food sources.

The in vivo and in vitro induction of anterior chamber associated immune deviation to myelin antigens in C57BL/6 mice.

Introduction of antigens into the anterior chamber (AC) of the eye generates a specific systemic form of tolerance that is termed AC-associated immune deviation (ACAID). Experimental autoimmune encephalomyelitis (EAE) is an animal model of the human CNS demyelinating diseases, including multiple sclerosis (MS) and acute disseminated encephalomyelitis. We investigated whether the encephalitogenic antigens myelin oligodendrocyte glycoprotein (MOG35-55) or myelin basic protein (MBP) induce ACAID in the EAE-prone C57BL/6 mice. We hypothesized that injection of MOG35-55/MBP induces antigen-specific tolerance whether via the AC route, the adoptive transfer of in vitro-generated MOG35-55-specific/MBP-specific ACAID antigen presenting cells (APCs), or the adoptive transfer of MOG35-55-specific/MBP-specific ACAID T regulatory cells (Tregs). ACAID is characterized by the specific impairment of delayed-type hypersensitivity (DTH) responses. Thus, DTH assays were used to test for ACAID following the AC injection of MOG35-55/MBP, or the intravenous injection of MOG35-55-specific/MBP-specific ACAID APCs. The functional local adoptive transfer (LAT) assays were used to examine the putative regulatory functions of in vitro generated MOG35-55-specific/MBP-specific Tregs. This report is the first to demonstrate the in vivo and in vitro induction of MOG35-55-specific/MBP-specific ACAID-mediated tolerance in C57BL/6 mice. These findings highlight the need for novel immunotherapeutic strategies for MS and optic neuritis.

Characterization of vitamin D3 biotransformation by the cell lysate of Actinomyces hyovaginalis CCASU-A11-2.

A former work conducted in our Lab, lead to in a effective scale up of vitamin D3 bioconversion into calcitriol by Actinomyces (A.) hyovaginalis isolate CCASU-A11-2 in Lab fermenter (14 L) resulting in 32.8 µg/100 mL of calcitriol. However, the time needed for such a bioconversion process was up to 5 days. Therefore, the objective of this study was to shorten the bioconversion time by using cell-free lysate and studying different factors influencing bioconversion. The crude cell lysate was prepared, freeze-dried, and primarily fractionated into nine fractions, of which, only three fractions, 50, 100, and 150 mM NaCl elution buffers showed 22, 12, and 2 µg/10 mL, calcitriol production, respectively. Ammonium sulfate was used for protein precipitation, and it did not affect the bioconversion process except at a concentration of 10%w/v. Secondary fractionation was carried out using 80 mL of the 50 mM NaCl elution buffer and the results showed the 80 mL eluent volume was enough for the complete elution of the active protein. The pH 7.8, temperature 28 °C, and 6 h reaction time were optimum for maximum calcitriol production (31 µg/10 mL). In conclusion, the transformation of vitamin D3 into calcitriol was successfully carried out within 6 h and at pH 7.8 and 28 °C using fractionated cell lysate. This process resulted in a 10-fold increase in calcitriol as compared to that produced in our previous study using a 14 L fermenter (32.8 µg/100 mL). Therefore, cell-free lysate should be considered for industrial and scaling up vitamin D3 bioconversion into calcitriol.

Incidence, identification and antibiotic resistance of Salmonella spp. in the well waters of Tadla Plain, Morocco.

Concerns about challenges with water availability in the Tadla Plain region of Morocco have grown as a result of groundwater contamination brought on by human activity, climate change, and insufficient groundwater management. The objective of the study is to measure the number of resistant bacteria in the groundwater of Beni Moussa and Beni Aamir, as well as to evaluate the level of water pollution in this area. 200 samples were therefore gathered from 43 wells over the course of four seasonal campaigns in 2017 and 2018. Additionally, the samples were examined to determine whether Salmonella species were present and if they were resistant to the 16 antibiotics that were tested. Salmonella spp. have been identified in 31 isolated strains in total, accounting for 18.02% of all isolated strains. Data on antibiotic resistance show that 58.1% of Salmonella spp. strains are multidrug-resistant (MDR); 38.7% of Salmonella strains are tolerant to at least six antibiotics, 19.4% to at least nine antibiotics, 9.7% to four to seven antibiotics, 6.5% to at least eleven antibiotics, and the remaining 3.2% to up to twelve antibiotics. A considerable level of resistance to cefepime (61.29%), imipenem (54.84%), ceftazidime (45.16%), ofloxacin (70.97%), and ertapenem (74.19%) was found in the data. Consequently, it is important to monitor and regulate the growth of MDR in order to prevent the groundwater's quality from declining.

Bioconversion of vitamin D3 into calcitriol by Actinomyces hyovaginalis isolate CCASU- A11-2.

Vitamin D3 is a fat-soluble prohormone that is activated inside the liver to produce 25-hydroxyvitamin D3 (calcidiol), and in the kidney to produce the fully active 1α, 25-dihydroxy vitamin D3 (calcitriol). A previous work piloted in our laboratory, resulted in a successful recovery of a local soil-promising Actinomyces hyovaginalis isolate CCASU-A11-2 capable of converting vitamin D3 into calcitriol. Despite the rising amount of research on vitamin D3 bioconversion into calcitriol, further deliberate studies on this topic can significantly contribute to the improvement of such a bioconversion process. Therefore, this work aimed to improve the bioconversion process, using the study isolate, in a 14 L laboratory fermenter (4 L fermentation medium composed of fructose (15 g/L), defatted soybean (15 g/L), NaCl (5 g/L), CaCO3 2 g/L); K2HPO4, (1 g/L) NaF (0.5 g/L) and initial of pH 7.8) where different experiments were undertaken to investigate the effect of different culture conditions on the bioconversion process. Using the 14 L laboratory fermenter, the calcitriol production was increased by about 2.5-fold (32.8 µg/100 mL) to that obtained in the shake flask (12.4 µg/100 mL). The optimal bioconversion conditions were inoculum size of 2% v/v, agitation rate of 200 rpm, aeration rate of 1 vvm, initial pH of 7.8 (uncontrolled); addition of vitamin D3 (substrate) 48 h after the start of the main culture. In conclusion, the bioconversion of vitamin D3 into calcitriol in a laboratory fermenter showed a 2.5-fold increase as compared to the shake flask level where, the important factors influencing the bioconversion process were the aeration rate, inoculum size, the timing of substrate addition, and the fixed pH of the fermentation medium. So, those factors should be critically considered for the scaling-up of the biotransformation process.

Mannose-binding lectin gene polymorphism in psoriasis and vitiligo: an observational study and computational analysis.

Introduction: Psoriasis and vitiligo are inflammatory autoimmune skin disorders with remarkable genetic involvement. Mannose-binding lectin (MBL) represents a significant immune molecule with one of its gene variants strongly linked to autoimmune diseases. Therefore, in this study, we investigated the role of the MBL variant, rs1800450, in psoriasis and vitiligo disease susceptibility. Methods: The study comprised performing in silico analysis, performing an observational study regarding psoriasis patients, and performing an observational study regarding vitiligo patients. Various in silico tools were used to investigate the impact of the selected mutation on the function, stability, post-translational modifications (PTMs), and secondary structures of the protein. In addition, a total of 489 subjects were enrolled in this study, including their demographic and clinicopathological data. Genotyping analysis was performed using real-time PCR for the single nucleotide polymorphism (SNP) rs1800450 on codon 54 of the MBL gene, utilizing TaqMan genotyping technology. In addition, implications of the studied variant on disease susceptibility and various clinicopathological data were analyzed. Results: Computational analysis demonstrated the anticipated effects of the mutation on MBL protein. Furthermore, regarding the observational studies, rs1800450 SNP on codon 54 displayed comparable results in our population relative to global frequencies reported via the 1,000 Genomes Project. This SNP showed no significant association with either psoriasis or vitiligo disease risk in all genetic association models. Furthermore, rs1800450 SNP did not significantly correlate with any of the demographic or clinicopathological features of both psoriasis and vitiligo. Discussion: Our findings highlighted that the rs1800450 SNP on the MBL2 gene has no role in the disease susceptibility to autoimmune skin diseases, such as psoriasis and vitiligo, among Egyptian patients. In addition, our analysis advocated the notion of the redundancy of MBL and revealed the lack of significant impact on both psoriasis and vitiligo disorders.