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1.
Bioact Mater ; 38: 109-123, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38699239

RESUMO

Approximately 740 million symptomatic patients are affected by otitis media every year. Being an inflammatory disease affecting the middle ear, it is one of the primary causes of tympanic membrane (TM) perforations, often resulting in impaired hearing abilities. Antibiotic therapy using broad-spectrum fluoroquinolones, such as ciprofloxacin (CIP), is frequently employed and considered the optimal route to treat otitis media. However, patients often get exposed to high dosages to compensate for the low drug concentration reaching the affected site. Therefore, this study aims to integrate tissue engineering with drug delivery strategies to create biomimetic scaffolds promoting TM regeneration while facilitating a localized release of CIP. Distinct electrospinning (ES) modalities were designed in this regard either by blending CIP into the polymer ES solution or by incorporating nanoparticles-based co-ES/electrospraying. The combination of these modalities was investigated as well. A broad range of release kinetic profiles was achieved from the fabricated scaffolds, thereby offering a wide spectrum of antibiotic concentrations that could serve patients with diverse therapeutic needs. Furthermore, the incorporation of CIP into the TM patches demonstrated a favorable influence on their resultant mechanical properties. Biological studies performed with human mesenchymal stromal cells confirmed the absence of any cytotoxic or anti-proliferative effects from the released antibiotic. Finally, antibacterial assays validated the efficacy of CIP-loaded scaffolds in suppressing bacterial infections, highlighting their promising relevance for TM applications.

2.
Vaccines (Basel) ; 12(3)2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38543969

RESUMO

BACKGROUND: Despite the efforts of the World Health Organization, some childhood viral diseases, for which there is already an effective vaccine, have not yet been eradicated. Among these, we find varicella, mumps, measles, and rubella, which although in most cases have a benign course, can in some cases be responsible for infectious outbreaks, especially in nosocomial settings. The aim of this study was to verify the immunological situation of a cohort of trainee obstetricians in Campania regarding varicella, mumps, measles, and rubella to be used as an example for the evaluation of possible preventive strategies to avoid infectious outbreaks. METHODS: All the samples collected and sent to the laboratory were eligible for analysis and have been included in the study. Specific IgG for varicella, measles, mumps, and rubella were assayed on serum samples taken from 517 trainee obstetricians using the enzyme-linked immunosorbent assay (ELISA) technique. The seropositivity results were statistically analyzed by correlating them to age group and gender. RESULTS: The results obtained show that a percentage of trainee obstetricians tested do not have an effective immunological coverage against at least one of the vaccine-preventable diseases considered, especially for mumps. CONCLUSIONS: Therefore, it is proposed to extend surveillance to other professionals in contact with frail patients and increase awareness of vaccination campaigns.

3.
Foods ; 13(6)2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38540945

RESUMO

Lactococcus lactis is a lactic acid bacterium (LAB), generally recognized as safe, and has been widely used in the food industry, especially in fermented dairy products. Numerous studies have evaluated the technological and probiotic properties of lactococci; however, few studies have reported the probiotic characteristics of L. lactis strains isolated from dairy products. In this work, probiotic potential, including survival in simulated gastric juice, tolerance to bile salts, hydrophobicity, and auto- and co-aggregation, was evaluated in L. lactis strains from natural whey starter cultures. The results highlighted the potential probiotic properties of some strains under study, which showed high values of hydrophobicity and auto-aggregation and low values of co-aggregation with the tested pathogenic strains. In addition, studies of safety parameters, such as antibiotic susceptibility and haemolytic activity, confirmed the safety status of all strains under study. Finally, the four most promising strains were investigated for their ability to inhibit the enteroinvasive Escherichia coli (EIEC) and Salmonella Typhimurium adhesion to epithelial cells, using a model of co-cultured epithelial cells. The results demonstrated that L. lactis strains A3-A5-I4-I7 showed the ability to compete with pathogens as well as the ability to exert a protective effect on cells previously infected with E. coli or S. Typhimurium. The identification of new probiotic LAB strains from dairy products aims to produce novel functional foods.

4.
Tissue Eng Part A ; 30(7-8): 340-356, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37962275

RESUMO

In this study, we develop a bio-based and bioactive nanofibrous patch based on bacterial cellulose (BC) and chitin nanofibrils (CNs) using an ionic liquid as a solvent for BC, aimed at tympanic membrane (TM) repair. Electrospun BC nanofiber meshes were produced via electrospinning, and surface-modified with CNs using electrospray. The rheology of the BC/ionic liquid system was investigated. The obtained CN/BC meshes underwent comprehensive morphological, physicochemical, and mechanical characterization. Cytotoxicity tests were conducted using L929 mouse fibroblasts, revealing a cell viability of 97.8%. In vivo tests on rabbit skin demonstrated that the patches were nonirritating. Furthermore, the CN/BC fiber meshes were tested in vitro using human dermal keratinocytes (HaCaT cells) and human umbilical vein endothelial cells as model cells for TM perforation healing. Both cell types demonstrated successful growth on these scaffolds. The presence of CNs resulted in improved indirect antimicrobial activity of the electrospun fiber meshes. HaCaT cells exhibited an upregulated mRNA expression at 6 and 24 h of key proinflammatory cytokines crucial for the wound healing process, indicating the potential benefits of CNs in the healing response. Overall, this study presents a natural and eco-sustainable fiber mesh with great promise for applications in TM repair, leveraging the synergistic effects of BC and CNs to possibly enhance tissue regeneration and healing. Impact statement Repair of tympanic membrane perforations following chronic otitis media is a main clinical issue in otologic surgery, where the underlying infection obstacles self-healing. To address this challenge, our study proposes a bio-based patch made of nanoscale carbohydrate materials (i.e., bacterial cellulose electrospun fibers and chitin nanofibrils) processed via green solvents. The scaffold is nonirritating in vivo, and cytocompatible with fibroblasts, endothelial cells, and keratinocytes. In epithelial cells, it stimulates the expression of the antimicrobial peptide human beta defensin 2, with a pathway of cytokine expression compatible with the wound healing process. Therefore, it could be applied with unsolved infective pathology.


Assuntos
Líquidos Iônicos , Nanofibras , Perfuração da Membrana Timpânica , Camundongos , Animais , Humanos , Coelhos , Celulose/farmacologia , Membrana Timpânica , Quitina/farmacologia , Células Endoteliais , Nanofibras/química , Alicerces Teciduais/química
5.
Lasers Med Sci ; 39(1): 7, 2023 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-38097851

RESUMO

In recent years, some treatments for esthetic and pathologic skin conditions have increasingly been based on the use of non-ablative neodymium-doped yttrium aluminum garnet (Nd:YAG) laser due to its greater penetration ability than other types of lasers, few contraindications, minimal side effects, no damage for epidermidis and the rapid recovery of the treated patients. The skin is frequently exposed to many stressors such as radiation, toxic substances, metabolites, foods, mechanical insults, and allergen exposition that cause oxidative damage and have a decisive influence on the aging process. The imbalance between reactive oxygen species, reactive nitrogen species, and the malfunctioning of the antioxidant defense system promotes the establishment of an excessive inflammatory process, which can induce various diseases including cancer and neurodegenerative disorders. The present study investigated the cytoprotective function of Q-switched Nd:YAG laser against stress aging and cell injury in HaCaT cells. We evaluated the effect of the laser on antioxidant defenses, inflammation, metalloproteinases' expression, and the AhR-Nrf2 pathway. Q-switched Nd:YAG is able to upregulate the AhR pathway and the expression of IL-6 and TGF-ß, which are involved in wound repair process, and to downregulate the expression of MMP-2 and 9, so preventing the collagen degradation. Q-switched Nd:YAG can stimulate the cellular antioxidant defenses by activating the AhR-Nrf2 system.


Assuntos
Lasers de Estado Sólido , Humanos , Lasers de Estado Sólido/uso terapêutico , Fator 2 Relacionado a NF-E2 , Antioxidantes , Queratinócitos/efeitos da radiação , Inflamação/radioterapia , Inflamação/patologia , Estresse Oxidativo
6.
J Fungi (Basel) ; 9(12)2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38132754

RESUMO

The skin serves as the first barrier against pathogen attacks, thanks to its multifunctional microbial community. Malassezia furfur is a commensal organism of normal cutaneous microflora but is also a cause of skin diseases. It acts on different cell pattern recognition receptors (TLRs, AhR, NLRP3 inflammasome) leading to cellular damage, barrier impairment, and inflammatory cytokines production. Lactobacillus spp. Is an endogenous inhabitant of healthy skin, and studies have proven its beneficial role in wound healing, skin inflammation, and protection against pathogen infections. The aim of our study is to demonstrate the ability of live Lactiplantibacillus plantarum to interfere with the harmful effects of the yeast on human keratinocytes (HaCat) in vitro. To enable this, the cells were treated with M. furfur, either alone or in the presence of L. plantarum. To study the inflammasome activation, cells require a stimulus triggering inflammation (LPS) before M. furfur infection, with or without L. plantarum. L. plantarum effectively counteracts all the harmful strategies of yeast, reducing the phospholipase activity, accelerating wound repair, restoring barrier integrity, reducing AhR and NLRP3 inflammasome activation, and, consequently, releasing inflammatory cytokines. Although lactobacilli have a long history of use in fermented foods, it can be speculated that they can also have health-promoting activities when topically applied.

7.
Pharmaceutics ; 15(11)2023 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-38004505

RESUMO

More sustainable and smart cosmeceuticals and nutraceuticals are necessary due to the ecological transition. In this study, a pullulan-based water solution containing chitin nanofibril-nano-lignin (CN-LG) complexes that encapsulate fish collagen polypeptide, allantoin and nicotinamide was electrospun onto a nonwoven substrate made of bamboo fibers to obtain a smart nanostructured bilayer system for releasing active molecules onto the skin or other body tissues. Infrared spectroscopy was used to characterize the composition of the bilayer system before and after rapid washing of the sample with distilled water and liquids mimicking physiological fluids. The viability of keratinocytes was studied as well as the antioxidant activity, protective activity towards UV light, metalloproteinase release of aged fibroblasts and the inhibitor activity against collagen degradation. Immunomodulatory tests were performed to investigate the anti-inflammatory activity of the bilayer system as well as its indirect antimicrobial activity. The results indicate that the bilayer system can be used in the production of innovative sustainable cosmeceuticals. In general, the adopted strategy can be extended to several smart treatments for fast release that can be commercialized as solid products, thus avoiding the use of preservatives and water.

8.
Pathogens ; 12(10)2023 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-37887704

RESUMO

Staphylococci, including Staphylococcus aureus and Staphylococcus epidermidis, are important human pathogens associated with potentially life-threatening infections. Their great biofilm-producing ability and the development of resistance mechanisms often account for therapeutic failure. Hence, the scientific community has devoted intensive efforts to the development of antimicrobial compounds active against both planktonic and sessile bacterial populations. Contextually, antimicrobial peptides (AMPs) are natural peptides produced by the innate immunity of every organism, representing a potential new therapeutic solution against human microbial pathogens. Our work focused on the in vitro activity of Oreoch-1, an AMP from the gills of Nile tilapia (Oreochromis niloticus), against standard and clinical S. aureus and S. epidermidis strains. Firstly, the cytotoxicity profile of Oreoch-1 was determined in human colon carcinoma cells. Secondly, its antibacterial spectrum was explored against staphylococcal strains to set up the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC). Our results highlighted an antibacterial activity in the range 6.25-25 µM, with a general bacteriostatic effect. Therefore, the biofilm-inhibitory property was assessed against S. aureus ATCC 25923 and S. epidermidis ATCC 35984, indicating a significant reduction in S. aureus biomass at sub-MIC concentrations. Overall, our study indicates Oreoch-1 as a promising new therapeutic weapon against staphylococcal infections.

9.
Microorganisms ; 11(9)2023 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-37764044

RESUMO

Urinary tract infections (UTIs) and catheter-associated UTIs (CAUTIs) are the principal hospital-acquired infections. Between these, bacterial prostatitis is believed to be the leading cause of recurrent UTIs in men under 50 years of age and is often unresponsive to antibiotic treatment. Proteus mirabilis is more commonly associated with UTIs in these abnormalities, especially in patients undergoing catheterization. Lactobacillus spp. are an important component of the human microbiota and occur in large quantities in foods. Probiotics are proposed as an alternative to antibiotic therapy in the treatment of urinary tract infections. In addition to their ability to produce antimicrobial metabolites, they have immunomodulatory activity and do not cause side effects. For this reason, the combination of probiotic microorganisms and conventional drugs was considered. The aim of this work was to select the most active Lactobacillus strains against two clinical isolates of P. mirabilis on bladder and prostatic epithelium, potentially exploitable to improve the clinical management of UTIs.

10.
Neurol Sci ; 44(11): 4107-4110, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37498399

RESUMO

BACKGROUND: Evusheld (EVS) was authorized by FDA and EMA as pre-exposure prophylaxis (PrEP) in people at high risk of severe Covid-19 outcomes, including people with Multiple Sclerosis (pwMS) on B-cell depleting (BCD) therapies-such as Ocrelizumab (OCR). In this population, no data on possible adverse drug reactions (ADRs) to EVS, B-lymphocytes (CD20 +) counts pre- and post-EVS injection, and comparison of percentage increase of IgG antibodies directed against SARS-CoV-2 trimeric spike protein (anti-TSP IgG) post-EVS and Covid-19 vaccine was available. The aim of this study was to better characterize the efficacy and safety profile of EVS in pwMS on BCD agents. METHODS: 17 pwMS on OCR agreed to receive EVS as PrEP for Covid-19. Sera samples were collected before the first dose of Covid-19 vaccine (T0), 4 weeks after the second dose (T1), 4 weeks after third dose (T2), immediately before (T3) and 4 weeks after (T4) EVS. RESULTS: Covid-19 vaccine ADRs were mild-to-moderate, whereas no ADRs were reported after EVS injection. A significant increase of anti-TSP IgG was found only at T0-T1 (Z = -3.059, p = .002) and T3-T4 (Z = -3.621, p < .001) time-points. The median percentage increase between T3-T4 was significantly higher with respect to the T0-T1(Z = -3.296, p = .001) and T1-T2 (Z = -3.059, p = .002) time-points. CONCLUSIONS: These results further support EVS safety and efficacy in boosting anti-TSP IgG titers in pwMS on OCR, with a statistically greater increase than that observed after completion of a full Covid-19 vaccine cycle, plus a booster dose.

11.
J Fungi (Basel) ; 9(3)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36983463

RESUMO

Oral candidiasis (OC) is an opportunistic fungal infection of the oral mucosae, sustained by Candida albicans or other non-albican Candida species (NAC), usually eradicated by conventional antifungals of the classes of azoles, polyenes, or derivative from echinocandins. OC usually occurs under predisposing local or systemic factors. C. lusitaniae is an opportunistic strain that is rarely responsible for human infection and occurs mainly in severe immunocompromised states. The present work reported an unconventional case of OC in an otherwise healthy immunocompetent woman sustained by C. lusitaniae and a multi-resistant strain of C. albicans.

12.
Biomedicines ; 11(3)2023 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-36979844

RESUMO

Background: The integrity of the intestinal barrier is fundamental to gut health and homeostasis; its damage can increase intestinal permeability, with translocation of bacteria and/or endotoxins from gut, and the onset of various intestinal diseases. Lactobacillus spp. is one of the most common probiotics normally found in fermented foods and dairy products and is known for its anti-inflammatory and immunomodulatory properties and for its ability to protect and enhance the intestinal barrier functions. The aim of this work was to evaluate the ability of different strains of Lactobacillus spp. to improve in vitro the integrity of the intestinal barrier, to exert anti-inflammatory and immunomodulatory activity and to prevent Salmonella Typhimurium and enteroinvasive Escherichia coli (EIEC) infections. Methods: We analyzed the cellular expression of tight junctions, antimicrobial peptide HBD-2, pro-inflammatory cytokines and the inhibition of pathogens adhesion and invasion in a model of co-cultured epithelial cells treated with Lactobacillus spp. Results: L. brevis, L. reuteri and L. rhamnosus proved to be more effective in protecting the intestinal epithelium. Conclusions: These in vitro studies can help select strains particularly active in their intended use to obtain consortia formulations that can have as much maximum yield as possible in terms of patient benefit.

13.
Antibiotics (Basel) ; 12(2)2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36830131

RESUMO

BACKGROUND: This study aims to evaluate the antimicrobial prescribing practices in hospital settings in Italy, focusing on the appropriateness of antibiotic use. METHODS: This study was carried out through a retrospective review of medical records of patients admitted in three public hospitals located in Campania Region (Italy) between 1 January and 31 December 2018. RESULTS: More than one third (34.2%) of patients received at least one inappropriate antibiotic prescription (antibiotic administered and not indicated). Being female, having a >1 Charlson comorbidity index score, and having a longer hospital stay were significant determinants of an inappropriate antibiotic prescription. Instead, patients who had had a non-urgent hospital admission, an infection on hospital admission, and a microbiological culture test during hospital stay were significantly less likely to have an inappropriate prescription. When the antibiotic prescriptions were analyzed, in 26.6% of cases they were not indicated, while among the 687 antibiotic prescriptions with indication, incorrect choice of antibiotics (36.8%) was the most common reason of the inappropriateness. CONCLUSIONS: The findings of the study indicate that the inappropriate use of antibiotics continues to be a relevant issue in the hospital setting and specific interventions are needed to encourage a wider utilization of diagnostic tools to practice targeted therapies and to counter the antimicrobial resistance.

14.
Clin Oral Investig ; 27(5): 2385-2394, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36719506

RESUMO

OBJECTIVES: The aim of the present randomized clinical trial (RCT) with a parallel arm design was to evaluate the clinical and microbiological efficacy of repeated ICG-aPDT as an adjunct to full-mouth subgingival debridement in the treatment of periodontitis. MATERIALS AND METHODS: Twenty-four periodontitis patients were treated with full-mouth ultrasonic subgingival debridement (FMUD). Initial sites with probing depth (PD) > 4 mm were randomly assigned to receive the test (ICG-aPDT with an 810 nm diode laser) or the control treatment (off-mode aPDT) one and four weeks after FMUD. Clinical parameters were registered after 3 and 6 months. The presence of the main periodontal pathogens in subgingival samples was assessed with real-time PCR. RESULTS: Both treatment modalities resulted in significant clinical improvements at 3 and 6 months. The only significant differences in favour of the test group were found at 6 months for a higher PD reduction in initial deep pockets (PD ≥ 6 mm) and a higher percentage of closed pockets (PD ≤ 4 mm/no bleeding on probing). Limited microbiological changes were observed in both groups after treatment with no inter-group difference, except for a more significant reduction in Aggregatibacter actinomycetemcomitans and Parvimonas micra levels in the test group at 3 months. CONCLUSION: The combination of repeated ICG-aPDT and FMUD provided no benefits except for selective clinical and microbiological improvements compared to FMUD alone. CLINICAL RELEVANCE: Based on the obtained results, only limited adjunctive effects could be found for the combined use of ICG-aPDT and FMUD. Further, well-designed RCT with larger sample sizes are required to confirm these findings. TRIAL REGISTRATION: ClinicalTrials.gov NCT04671394.


Assuntos
Anti-Infecciosos , Periodontite Crônica , Fotoquimioterapia , Humanos , Verde de Indocianina/uso terapêutico , Raspagem Dentária/métodos , Periodontite Crônica/tratamento farmacológico , Fotoquimioterapia/métodos , Anti-Infecciosos/uso terapêutico , Aplainamento Radicular/métodos
15.
Photochem Photobiol Sci ; 22(6): 1223-1231, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36656508

RESUMO

In this study, P-doped TiO2 photocatalysts with different molar percentages (in the range 0.071-1.25 mol %) of the non-metallic element were prepared and their photocatalytic activity under visible light irradiation was tested. All achieved samples were characterized by XRD, Raman, UV-Vis DRS and SEM-EDX techniques. XRD and Raman analysis showed that all doped photocatalysts were in anatase phase and evidenced that P ions were successfully incorporated into the TiO2 crystal lattice, affecting also the crystallinity degree of the P-doped TiO2 photocatalysts. Noticeably, the UV-Vis DRS spectra evidenced that the highest redshift in absorption edge was observed for the photocatalyst with the lowest P content (0.071PT), which showed also the lowest bandgap (2.9 eV). The photocatalytic performances of all P-doped TiO2 samples were compared with that of commercial TiO2 by evaluating the decolorization of methylene blue (MB) dye under visible light irradiation. Results showed that phosphorus doping strongly promoted photocatalytic activity in the presence of visible light. Furthermore, the most active photocatalyst in visible light tests (0.071PT) also showed better photocatalytic activity than commercial TiO2 in the decolorization of MB under simulated sunlight irradiation. Finally, 0.071PT photocatalyst was preliminarily tested against Escherichia coli (E. coli) under simulated solar light, showing an inactivation efficiency of 90% after 2 h of treatment time.


Assuntos
Escherichia coli , Luz , Escherichia coli/efeitos da radiação , Catálise , Titânio/química , Azul de Metileno
16.
Infect Dis Ther ; 12(2): 727-734, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36522526

RESUMO

BACKGROUND: The prevalence of certain multidrug-resistant organisms (MDROs), especially Gram-negative bacteria, is dramatically increasing in patient care settings, including pediatric and neonatal units. However, most of the new drugs available for the treatment of MDROs have not yet been studied in children and newborns. CASE REPORT: We report the clinical case of a preterm neonate, born at 31 weeks gestation + 1 day of age by emergency Cesarean Section (CS), with a bloodstream infection (BSI) due to a Verona integron-borne metallo-ß-lactamase (VIM)-producing Klebsiella pneumoniae. We successfully treated the infection with cefiderocol in an off-label regimen at the following dose: loading dose 60 mg/kg and then 40 mg/kg every 8 h in extended infusion for 9 days. The baby showed a quick clinical and biochemical improvement and tolerated well the treatment. Follow-up blood cultures at 48 h after the start of cefiderocol were negative. CONCLUSIONS: Antimicrobial-resistant pathogens are of increasing concern in neonatal settings. More studies in this unique population are necessary to better describe the pharmacokinetic and pharmacodynamic profile of the new drugs against MDROs, such as cefiderocol, and to define a proper effective dose.

17.
Front Bioeng Biotechnol ; 10: 1007004, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36394050

RESUMO

Several Levilactobacillus brevis strains have the potential to be used as probiotics since they provide health benefits due to the interaction of live cells, and of their secreted products, with the host (tissues). Therefore, the development of simple fermentation processes that improve cell viability to reduce industrial production costs, and at the same time the characterization and biological evaluation of cell-free postbiotics that can further promote application, are of great interest. In the present study, small scale batch fermentations on semi defined media, deprived of animal derived raw materials, were used to optimize growth of L. brevis SP48, reaching 1.2 ± 0.4 × 1010 CFU/ml of viable cells after 16 h of growth. Displacement, competition, and inhibition assays compared the effect, on Helicobacter pylori, of L. brevis cells to that of its partially purified potentially postbiotic fraction rich in exopolysaccharides and proteins. The expression of pro and anti-inflammatory biochemical markers indicated that both samples activated antimicrobial defenses and innate immunity in a gastric model. Moreover, these compounds also acted as modulators of the inflammatory response in a gut in vitro model. These data demonstrate that the high molecular weight compounds secreted by L. brevis SP48 can contrast H. pylori and reduce inflammation related to intestinal bowel disease, potentially overcoming issues related to the preservation of probiotic viability.

18.
Front Cell Infect Microbiol ; 12: 1009415, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36310877

RESUMO

Escherichia coli is one of the commensal species most represented in the intestinal microbiota. However, there are some strains that can acquire new virulence factors that enable them to adapt to new intestinal niches. These include enteroinvasive E. coli (EIEC) that is responsible for the bacillary dysentery that causes severe diarrheal symptoms in both children and adults. Due to the increasing onset of antibiotic resistance phenomena, scientific research is focused on the study of other therapeutic approaches for the treatment of bacterial infections. A promising alternative could be represented by antimicrobial peptides (AMPs), that have received widespread attention due to their broad antimicrobial spectrum and low incidence of bacterial resistance. AMPs modulate the immune defenses of the host and regulate the composition of microbiota and the renewal of the intestinal epithelium. With the aim to investigate an alternative therapeutic approach, especially in the case of antibiotic resistance, in this work we created a line of intestinal epithelial cells able to express high concentrations of AMP human ß-defensin-2 (HBD-2) in order to test its ability to interfere with the pathogenicity mechanisms of EIEC. The results showed that HBD-2 is able to significantly reduce the expression of the proinflammatory cytokines by intestinal epithelial cells, the invasiveness ability of EIEC and the expression of invasion-associated genes.


Assuntos
Escherichia coli , beta-Defensinas , Criança , Humanos , Peptídeos Antimicrobianos , beta-Defensinas/farmacologia , Células CACO-2 , Diarreia/microbiologia , Escherichia coli/genética , Fatores de Virulência/genética
19.
J Neurol ; 269(12): 6185-6192, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35879563

RESUMO

BACKGROUND: The assessment of the safety and the humoral response to a third booster dose of the BNT162b2 mRNA COVID-19 vaccine is relevant in patients with Multiple Sclerosis (pwMS) treated with Ocrelizumab (OCR) or Fingolimod (FNG). METHODS: Serum samples were collected from Healthy controls (HCs) and pwMS treated with OCR or FNG at the following time-points: before the first of two vaccine doses (T0); 8 (T1), 16 (T2), 24 (T3) weeks after the first dose; within 8 weeks before (T0b) and after (T1b) the booster dose. IgG antibodies to SARS-CoV-2 trimeric spike protein (Anti-TSP IgG) were quantified and expressed as binding antibody units (BAU)/mL. RESULTS: 40 HCs, 28 pwMS on OCR and 19 on FNG were included. At T0b 12 (42.9%) pwMS on OCR and 6 (31.6%) on FNG were still positive while, at T1b 16 (57.14%) pwMS on OCR and 16 (84.2%) on FNG, passed the threshold of positivity. The increase of Anti-TSP IgG levels at T1b was higher for: (i) HCs with respect to OCR (p < 0.001) and FNG (p = 0.032) groups; (ii) pwMS on FNG compared with pwMS on OCR (p < 0.001). No socio-demographic, clinical or laboratory variables were able to predict the anti-TSP IgG increase between T0b and T1b. Neither clinical relapses nor severe adverse events were reported in pwMS after each dose of vaccine. CONCLUSIONS: The third booster dose of BNT162b2 mRNA vaccine to OCR- and FNG-treated pwMS revives the humoral response, independently of any clinical variable, and manifests a good safety and tolerability profile.


Assuntos
COVID-19 , Esclerose Múltipla , Humanos , Cloridrato de Fingolimode/efeitos adversos , Esclerose Múltipla/tratamento farmacológico , Vacina BNT162 , Vacinas contra COVID-19/efeitos adversos , RNA Mensageiro , COVID-19/prevenção & controle , SARS-CoV-2 , Imunoglobulina G , Anticorpos Antivirais , Vacinas de mRNA
20.
Biotechnol Rep (Amst) ; 34: e00732, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35686014

RESUMO

Probiotics are living microorganisms that give beneficial health effects while consumed, and each strain possesses diverse and unique properties and also different technological characteristics that affect its ability to be produced at large scale. Limosilactobacillus fermentum is a widely studied member of probiotics, however, few data are available on the development of fermentation and downstream processes for the production of viable biomasses for potential industrial applications. In the present study a novel L. fermentum strain was isolated from buffalo milk and used as test example for biotechnological process development. The strain was able to produce up to 109 CFU/mL on a (glucose based) semi-defined medium deprived of animal-derived raw materials up to the pilot scale (150 L), demonstrating improved results compared to commonly used, although industrially not suitable, media rich of casein and beef extract. The study of strain behavior in batch experiments indicated that the highest concentration of viable cells was reached after only 8 h of growth, greatly shortening the process. Moreover, initial concentrations of glucose in the medium above 30 g/L, if not supported by higher nitrogen concentrations, reduced the yield of biomass and increased production of heterolactic fermentation by-products. Biomass concentration via microfiltration on hollow fibers, and subsequent spray-drying allowed to recover about 5.7 × 1010CFU/gpowder of viable cells, indicating strain resistance to harsh processing conditions. Overall, these data demonstrate the possibility to obtain and maintain adequate levels of viable L. fermentum cells by using a simple approach that is potentially suitable for industrial development. Moreover, since often exopolysaccharides produced by lactobacilli contribute to the strain's functionality, a partial characterization of the EPS produced by the newly identified L. fermentum strain was carried out. Finally, the effect of L. fermentum versus H. pylori in a gastric epithelial cell model was evaluated demonstrating its ability to stimulate the response of the immune system and displace the infective agent.

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