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1.
J Transl Med ; 22(1): 574, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38886736

RESUMO

BACKGROUND: The innate immunity acts during the early phases of infection and its failure in response to a multilayer network of co-infections is cause of immune system dysregulation. Epidemiological SARS-CoV-2 infections data, show that Influenza Virus (FLU-A-B-C) and Respiratory Syncytial Virus (RSV) are co-habiting those respiratory traits. These viruses, especially in children (mostly affected by 'multi-system inflammatory syndrome in children' [MIS-C] and the winter pandemic FLU), in the aged population, and in 'fragile' patients are causing alteration in immune response. Then, bacterial and fungal pathogens are also co-habiting the upper respiratory traits (e.g., Staphylococcus aureus and Candida albicans), thus contributing to morbidity in those COVID-19 affected patients. METHODS: Liquid chromatography coupled with high-resolution mass spectrometry using the quadrupole orbital ion trap analyser (i.e., UHPLC-Q-Orbitrap HRMS) was adopted to measure the polyphenols content of a new nutraceutical formula (Solution-3). Viral infections with SARS-CoV-2 (EG.5), FLU-A and RSV-A viruses (as performed in BLS3 authorised laboratory) and real time RT-PCR (qPCR) assay were used to test the antiviral action of the nutraceutical formula. Dilution susceptibility tests have been used to estimate the minimum inhibitory and bactericidal concentration (MIC and MBC, respectively) of Solution-3 on a variety of microorganisms belonging to Gram positive/ negative bacteria and fungi. Transcriptomic data analyses and functional genomics (i.e., RNAseq and data mining), coupled to qPCR and ELISA assays have been used to investigate the mechanisms of action of the nutraceutical formula on those processes involved in innate immune response. RESULTS: Here, we have tested the combination of natural products containing higher amounts of polyphenols (i.e., propolis, Verbascum thapsus L., and Thymus vulgaris L.), together with the inorganic long chain polyphosphates 'polyPs' with antiviral, antibacterial, and antifungal behaviours, against SARS-CoV-2, FLU-A, RSV-A, Gram positive/ negative bacteria and fungi (i.e., Candida albicans). These components synergistically exert an immunomodulatory action by enhancing those processes involved in innate immune response (e.g., cytokines: IFNγ, TNFα, IL-10, IL-6/12; chemokines: CXCL1; antimicrobial peptides: HBD-2, LL-37; complement system: C3). CONCLUSION: The prophylactic antimicrobial success of this nutraceutical formula against SARS-CoV-2, FLU-A and RSV-A viruses, together with the common bacteria and fungi co-infections as present in human oral cavity, is expected to be valuable.


Assuntos
Antivirais , COVID-19 , Imunidade Inata , SARS-CoV-2 , Humanos , Imunidade Inata/efeitos dos fármacos , Antivirais/farmacologia , COVID-19/imunologia , COVID-19/virologia , SARS-CoV-2/efeitos dos fármacos , SARS-CoV-2/imunologia , Anti-Infecciosos/farmacologia , Polifenóis/farmacologia , Suplementos Nutricionais
2.
Angew Chem Int Ed Engl ; 63(17): e202401541, 2024 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-38393988

RESUMO

Veillonella parvula, prototypical member of the oral and gut microbiota, is at times commensal yet also potentially pathogenic. The definition of the molecular basis tailoring this contrasting behavior is key for broadening our understanding of the microbiota-driven pathogenic and/or tolerogenic mechanisms that take place within our body. In this study, we focused on the chemistry of the main constituent of the outer membrane of V. parvula, the lipopolysaccharide (LPS). LPS molecules indeed elicit pro-inflammatory and immunomodulatory responses depending on their chemical structures. Herein we report the structural elucidation of the LPS from two strains of V. parvula and show important and unprecedented differences in both the lipid and carbohydrate moieties, including the identification of a novel galactofuranose and mannitol-containing O-antigen repeating unit for one of the two strains. Furthermore, by harnessing computational studies, in vitro human cell models, as well as lectin binding solid-phase assays, we discovered that the two chemically diverse LPS immunologically behave differently and have attempted to identify the molecular determinant(s) governing this phenomenon. Whereas pro-inflammatory potential has been evidenced for the lipid A moiety, by contrast a plausible "immune modulating" action has been proposed for the peculiar O-antigen portion.


Assuntos
Lipopolissacarídeos , Antígenos O , Humanos , Lipopolissacarídeos/farmacologia , Lipopolissacarídeos/metabolismo , Antígenos O/metabolismo , Veillonella/metabolismo , Lipídeo A
3.
Chembiochem ; 24(10): e202300183, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37042436

RESUMO

Marine bacteria, which are often described as chemical gold, are considered an exceptional source of new therapeutics. Considerable research interest has been given to lipopolysaccharides (LPSs), the main components of the Gram-negative outer membrane. LPS and its lipid A portion from marine bacteria are known to exhibit a tricky chemistry that has been often associated with intriguing properties such as behaving as immune adjuvants or anti-sepsis molecules. In this scenario, we report the structural determination of the lipid A from three marine bacteria within the Cellulophaga genus, which showed to produce an extremely heterogenous blend of tetra- to hexa-acylated lipid A species, mostly carrying one phosphate and one D-mannose on the glucosamine disaccharide backbone. The ability of the three LPSs in activating TLR4 signaling revealed a weaker immunopotential by C. baltica NNO 15840T and C. tyrosinoxydans EM41T , while C. algicola ACAM 630T behaved as a more potent TLR4 activator.


Assuntos
Flavobacteriaceae , Gammaproteobacteria , Lipídeo A/química , Receptor 4 Toll-Like , Lipopolissacarídeos/química
4.
FASEB J ; 35(12): e22026, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34818435

RESUMO

Antibiotic resistance is becoming a severe obstacle in the fight against acute and chronic infectious diseases that accompany most degenerative illnesses from neoplasia to osteo-arthritis and obesity. Currently, the race is on to identify pharmaceutical molecules or combinations of molecules able to prevent or reduce the insurgence and/or progression of infectivity. Attempts to substitute antibiotics with antimicrobial peptides have, thus far, met with little success against multidrug-resistant (MDR) bacterial strains. During the last decade, we designed and studied the activity and features of human ß-defensin analogs, which are salt-resistant, and hence active also under high salt concentrations as, for instance, in cystic fibrosis. Herein, we describe the design, synthesis, and major features of a new 21 aa long molecule, peptide γ2. The latter derives from the γ-core of the ß-defensin natural molecules, a small fragment of these molecules still bearing high antibacterial activity. We found that peptide γ2, which contains only one disulphide bond, recapitulates most of the biological properties of natural human ß-defensins and can also counteract both Gram-positive and Gram-negative MDR bacterial strains and biofilm formation. Moreover, it has great stability in human serum thereby enhancing its antibacterial presence and activity without cytotoxicity in human cells. In conclusion, peptide γ2 is a promising new weapon also in the battle against intractable infectious diseases.


Assuntos
Antibacterianos/farmacologia , Peptídeos Antimicrobianos/farmacologia , Bactérias/crescimento & desenvolvimento , Biofilmes/crescimento & desenvolvimento , beta-Defensinas/química , Bactérias/efeitos dos fármacos , Biofilmes/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla , Humanos , Testes de Sensibilidade Microbiana
5.
BMC Infect Dis ; 21(1): 350, 2021 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-33853532

RESUMO

BACKGROUND: The SARS-CoV-2 infection has emerged as a rapidly spreading infection. Today it is relatively easy to isolate Covid-19 symptomatic cases, while remains problematic to control the disease spread by infected but symptom-free individuals. The control of this possible path of contagion requires drastic measures of social distancing, which imply the suspension of most activities and generate economic and social issues. This study is aimed at estimating the percentage of asymptomatic SARS-CoV-2 infection in a geographic area with relatively low incidence of Covid-19. METHODS: Blood serum samples from 388 healthy volunteers were analyzed for the presence of anti-SARS-CoV-2 IgG by using an ELISA assay based on recombinant viral nucleocapsid protein. RESULTS: We found that 7 out of 388 healthy volunteers, who declared no symptoms of Covid-19, like fever, cough, fatigue etc., in the preceding 5 months, have bona fide serum anti-SARS-CoV-2 IgG, that is 1.8% of the asymptomatic population (95% confidence interval: 0.69-2.91%). CONCLUSIONS: The estimated range of asymptomatic individuals with anti-SARS-CoV-2 IgG should be between 26,565 and 112, 350. In the same geographic area, there are 4665 symptomatic diagnosed cases.


Assuntos
Anticorpos Antivirais/sangue , Infecções Assintomáticas , COVID-19/epidemiologia , Adulto , Idoso , Humanos , Imunoglobulina G/sangue , Incidência , Itália/epidemiologia , Pessoa de Meia-Idade , Adulto Jovem
6.
Cell Microbiol ; 21(8): e13035, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31042331

RESUMO

We previously identified a Neisseria flavescens strain in the duodenum of celiac disease (CD) patients that induced immune inflammation in ex vivo duodenal mucosal explants and in CaCo-2 cells. We also found that vesicular trafficking was delayed after the CD-immunogenic P31-43 gliadin peptide-entered CaCo-2 cells and that Lactobacillus paracasei CBA L74 (L. paracasei-CBA) supernatant reduced peptide entry. In this study, we evaluated if metabolism and trafficking was altered in CD-N. flavescens-infected CaCo-2 cells and if any alteration could be mitigated by pretreating cells with L. paracasei-CBA supernatant, despite the presence of P31-43. We measured CaCo-2 bioenergetics by an extracellular flux analyser, N. flavescens and P31-43 intracellular trafficking by immunofluorescence, cellular stress by TBARS assay, and ATP by bioluminescence. We found that CD-N. flavescens colocalised more than control N. flavescens with early endocytic vesicles and more escaped autophagy thereby surviving longer in infected cells. P31-43 increased colocalisation of N. flavescens with early vesicles. Mitochondrial respiration was lower (P < .05) in CD-N. flavescens-infected cells versus not-treated CaCo-2 cells, whereas pretreatment with L. paracasei-CBA reduced CD-N. flavescens viability and improved cell bioenergetics and trafficking. In conclusion, CD-N. flavescens induces metabolic imbalance in CaCo-2 cells, and the L. paracasei-CBA probiotic could be used to correct CD-associated dysbiosis.


Assuntos
Lacticaseibacillus paracasei/química , Mitocôndrias/efeitos dos fármacos , Neisseria/efeitos dos fármacos , Fosforilação Oxidativa/efeitos dos fármacos , Probióticos/farmacologia , Trifosfato de Adenosina/agonistas , Trifosfato de Adenosina/metabolismo , Autofagossomos/efeitos dos fármacos , Autofagossomos/metabolismo , Autofagossomos/microbiologia , Autofagia/efeitos dos fármacos , Autofagia/genética , Células CACO-2 , Doença Celíaca/metabolismo , Doença Celíaca/microbiologia , Doença Celíaca/terapia , Meios de Cultivo Condicionados/farmacologia , Disbiose/metabolismo , Disbiose/microbiologia , Disbiose/terapia , Expressão Gênica , Gliadina/antagonistas & inibidores , Gliadina/farmacologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Interações Hospedeiro-Patógeno/genética , Humanos , Lacticaseibacillus paracasei/fisiologia , Proteína 2 de Membrana Associada ao Lisossomo/genética , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Proteínas Associadas aos Microtúbulos/genética , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/metabolismo , Neisseria/genética , Neisseria/crescimento & desenvolvimento , Neisseria/patogenicidade , Fragmentos de Peptídeos/antagonistas & inibidores , Fragmentos de Peptídeos/farmacologia , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Vesículas Transportadoras/efeitos dos fármacos , Vesículas Transportadoras/metabolismo , Vesículas Transportadoras/ultraestrutura , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
7.
G Ital Med Lav Ergon ; 42(2): 73-81, 2020 06.
Artigo em Italiano | MEDLINE | ID: mdl-32614536

RESUMO

SUMMARY: During COVID-19 pandemic crisis, Italian Government has approved Law Decree no. 18 of 17 march 2020, in which art. 15 allows enterprises to produce, import and commercialize surgical masks notwithstanding the current rules of product certification. It is just required that the interested enterprises send to the Italian National Institute of Health a selfcertification in which they declare the technical characteristics of the masks and that masks are produced according to the safety requirements. In this context, a technical-scientific unit was established at the University of Napoli Federico II to provide interested enterprises with state-of-the-art consultancy, testing and measurement services, adhering to rigorous scientific protocols. Characterization tests were carried out on 163 surgical masks and/or materials for their construction and they have enabled the identification of pre-screening criteria to simplify the procedure for evaluating surgical masks using methods for assessing the filtration efficiency of particles and aerosols. Based on experimental results, it has been observed that a filtration efficiency for particles with sizes larger that 650 nm (PFE>650) exceeding 35% might guarantees a bacterial filtration efficiency (BFE) higher than 95% while BFE values higher than 98% are obtained when the PFE>650 is larger than 40%. PFE measurement is extremely simpler with respect to BFE, the latter being time-consuming and requiring specific equipment and methods for its realization. Many tested materials have shown the capability to assure high filtration efficiencies but Spundonded-Meltblown-Spunbonded (SMS), that are layers of non-woven fabric with different weights of Meltblown, can simultaneously guarantee high particle filtration efficiencies with pressure drop values (breathability) in the limits to classify the surgical masks as Type II/IIR. In fact, the fabric products analyzed so far have not been able to simultaneously guarantee adequate BFE and breathability values. On the contrary, Spunbonds of adequate weights can virtually verify both requirements and accredit themselves as possible materials for the production of surgical masks, at least of Type I. Further studies are needed to verify the possibility of producing low-cost, reusable surgical masks that could meet the criteria of circular economy.


Assuntos
Infecções por Coronavirus/prevenção & controle , Filtração/instrumentação , Máscaras/normas , Pandemias/prevenção & controle , Pneumonia Viral/prevenção & controle , Têxteis/normas , COVID-19 , Desenho de Equipamento , Reutilização de Equipamento , Humanos , Itália , Teste de Materiais , Tamanho da Partícula
8.
Infect Immun ; 87(4)2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30718288

RESUMO

In serogroup C Neisseria meningitidis, the cssA (siaA) gene codes for an UDP-N-acetylglucosamine 2-epimerase that catalyzes the conversion of UDP-N-acetyl-α-d-glucosamine into N-acetyl-d-mannosamine and UDP in the first step in sialic acid biosynthesis. This enzyme is required for the biosynthesis of the (α2→9)-linked polysialic acid capsule and for lipooligosaccharide (LOS) sialylation. In this study, we have used a reference serogroup C meningococcal strain and an isogenic cssA knockout mutant to investigate the pathogenetic role of surface-exposed sialic acids in a model of meningitis based on intracisternal inoculation of BALB/c mice. Results confirmed the key role of surface-exposed sialic acids in meningococcal pathogenesis. The 50% lethal dose (LD50) of the wild-type strain 93/4286 was about four orders of magnitude lower than that of the cssA mutant. Compared to the wild-type strain, the ability of this mutant to replicate in brain and spread systemically was severely impaired. Evaluation of brain damage evidenced a significant reduction in cerebral hemorrhages in mice infected with the mutant in comparison with the levels in those challenged with the wild-type strain. Histological analysis showed the typical features of bacterial meningitis, including inflammatory cells in the subarachnoid, perivascular, and ventricular spaces especially in animals infected with the wild type. Noticeably, 80% of mice infected with the wild-type strain presented with massive bacterial localization and accompanying inflammatory infiltrate in the corpus callosum, indicating high tropism of meningococci exposing sialic acids toward this brain structure and a specific involvement of the corpus callosum in the mouse model of meningococcal meningitis.


Assuntos
Proteínas de Bactérias/genética , Meningite Meningocócica/microbiologia , Ácido N-Acetilneuramínico/metabolismo , Neisseria meningitidis Sorogrupo C/patogenicidade , Animais , Proteínas de Bactérias/metabolismo , Encéfalo/microbiologia , Encéfalo/patologia , Carboidratos Epimerases/genética , Carboidratos Epimerases/metabolismo , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Humanos , Meningite Meningocócica/mortalidade , Meningite Meningocócica/patologia , Camundongos , Camundongos Endogâmicos BALB C , Neisseria meningitidis Sorogrupo C/genética , Neisseria meningitidis Sorogrupo C/metabolismo , Virulência
9.
New Microbiol ; 40(2): 151-154, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28368078

RESUMO

This report describes a case of congenital toxoplasmosis in a newborn in Southern Italy. A pregnant mother had been admitted at the 20th week of her pregnancy on account of pharyngodynia and laterocervical lymphadenopathy. Although serological testing of the mother's serum documented a seroconversion with positive IgG and IgM anti-Toxoplasma antibodies during II trimester, the woman refused to perform prenatal diagnosis for congenital toxoplasmosis. Fetal ultrasound scan already showed mild asymmetrical triventricular hydrocephaly and cerebral calcifications. After birth, real-time PCR on cerebrospinal fluid and blood samples of the newborn showed a positive result for 529bp-repeat element DNA of T. gondii, In addition brain magnetic resonance imaging and computed tomography showed a characteristic diffuse brain tissue loss associated with hydrocephalus. For the first time molecular characterization of T. gondii isolate was performed directly from the newborn's CSF samples by using nested-PCR-RFLP of sag-2 and pk1 genes. The PCR-RLFP analysis revealed that the isolate belongs to the clonal type II, the predominant lineage causing human toxoplasmosis, as confirmed by DNA sequencing.


Assuntos
Toxoplasma/genética , Toxoplasmose Congênita/parasitologia , Adulto , Anticorpos Antiprotozoários/sangue , Sequência de Bases , Líquido Cefalorraquidiano/parasitologia , DNA de Protozoário/líquido cefalorraquidiano , DNA de Protozoário/química , Feminino , Genótipo , Técnicas de Genotipagem , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Recém-Nascido , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Gravidez , Toxoplasma/classificação , Toxoplasma/imunologia , Toxoplasmose Congênita/líquido cefalorraquidiano , Toxoplasmose Congênita/diagnóstico por imagem
10.
Am J Gastroenterol ; 111(6): 879-90, 2016 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27045926

RESUMO

OBJECTIVES: Celiac disease (CD)-associated duodenal dysbiosis has not yet been clearly defined, and the mechanisms by which CD-associated dysbiosis could concur to CD development or exacerbation are unknown. In this study, we analyzed the duodenal microbiome of CD patients. METHODS: The microbiome was evaluated in duodenal biopsy samples of 20 adult patients with active CD, 6 CD patients on a gluten-free diet, and 15 controls by DNA sequencing of 16S ribosomal RNA libraries. Bacterial species were cultured, isolated and identified by mass spectrometry. Isolated bacterial species were used to infect CaCo-2 cells, and to stimulate normal duodenal explants and cultured human and murine dendritic cells (DCs). Inflammatory markers and cytokines were evaluated by immunofluorescence and ELISA, respectively. RESULTS: Proteobacteria was the most abundant and Firmicutes and Actinobacteria the least abundant phyla in the microbiome profiles of active CD patients. Members of the Neisseria genus (Betaproteobacteria class) were significantly more abundant in active CD patients than in the other two groups (P=0.03). Neisseria flavescens (CD-Nf) was the most abundant Neisseria species in active CD duodenum. Whole-genome sequencing of CD-Nf and control-Nf showed genetic diversity of the iron acquisition systems and of some hemoglobin-related genes. CD-Nf was able to escape the lysosomal compartment in CaCo-2 cells and to induce an inflammatory response in DCs and in ex-vivo mucosal explants. CONCLUSIONS: Marked dysbiosis and an abundance of a peculiar CD-Nf strain characterize the duodenal microbiome in active CD patients thus suggesting that the CD-associated microbiota could contribute to the many inflammatory signals in this disorder.


Assuntos
Doença Celíaca/microbiologia , Duodeno/microbiologia , Disbiose/microbiologia , Metagenômica , Neisseria/isolamento & purificação , Actinobacteria/classificação , Actinobacteria/isolamento & purificação , Adulto , Biópsia , Células CACO-2 , Dieta Livre de Glúten , Ensaio de Imunoadsorção Enzimática , Feminino , Imunofluorescência , Humanos , Itália , Masculino , Microbiota , Neisseria/classificação , Proteobactérias/classificação , Proteobactérias/isolamento & purificação
11.
Antimicrob Agents Chemother ; 59(12): 7637-49, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26416867

RESUMO

Rifampin chemoprophylaxis against Neisseria meningitidis infections led to the onset of rifampin resistance in clinical isolates harboring point mutations in the rpoB gene, coding for the RNA polymerase ß chain. These resistant strains are rare in medical practice, suggesting their decreased fitness in the human host. In this study, we isolated rifampin-resistant rpoB mutants from hypervirulent serogroup C strain 93/4286 and analyzed their different properties, including the ability to grow/survive in different culture media and in differentiated THP-1 human monocytes and to compete with the wild-type strain in vitro. Our results demonstrate that different rpoB mutations (H553Y, H553R, and S549F) may have different effects, ranging from low- to high-cost effects, on bacterial fitness in vitro. Moreover, we found that the S549F mutation confers temperature sensitivity, possibly explaining why it is observed very rarely in clinical isolates. Comparative high-throughput RNA sequencing analysis of bacteria grown in chemically defined medium demonstrated that the low-cost H553Y substitution resulted in global transcriptional changes that functionally mimic the stringent response. Interestingly, many virulence-associated genes, including those coding for meningococcal type IV pili, porin A, adhesins/invasins, IgA protease, two-partner secretion system HrpA/HrpB, enzymes involved in resistance to oxidative injury, lipooligosaccharide sialylation, and capsular polysaccharide biosynthesis, were downregulated in the H553Y mutant compared to their level of expression in the wild-type strain. These data might account for the reduced capacity of this mutant to grow/survive in differentiated THP-1 cells and explain the rarity of H553Y mutants among clinical isolates.


Assuntos
RNA Polimerases Dirigidas por DNA/genética , Farmacorresistência Bacteriana Múltipla/genética , Regulação Bacteriana da Expressão Gênica , Aptidão Genética , Neisseria meningitidis/genética , Fatores de Virulência/genética , Adesinas Bacterianas/genética , Adesinas Bacterianas/metabolismo , Substituição de Aminoácidos , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Linhagem Celular , Meios de Cultura , RNA Polimerases Dirigidas por DNA/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Monócitos/efeitos dos fármacos , Monócitos/microbiologia , Mutação , Neisseria meningitidis/efeitos dos fármacos , Neisseria meningitidis/metabolismo , Porinas/genética , Porinas/metabolismo , Rifampina/farmacologia , Serina Endopeptidases/genética , Serina Endopeptidases/metabolismo , Transcrição Gênica , Fatores de Virulência/metabolismo
12.
New Microbiol ; 37(4): 567-71, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25387296

RESUMO

Cystic fibrosis is a genetic disorder associated with a polymicrobial lung infection where classical pathogens and newly identified bacteria may interact. Inquilinus limosus is an a-proteobacterium recently isolated in the airways of cystic fibrosis patient. We report the first case in Italy of I.limosus isolation from the sputum sample of a cystic fibrosis patient. The patient is a 20-years-old man with cystic fibrosis, regularly attending the Regional Care Center for Cystic Fibrosis at the Federico II University Hospital of Naples. Microbiological culture methods detected a mu- coid gram negative bacillus in the patient's sputum sample. The isolate exhibited a distinct antimicrobial suscep- tibility profile with a high MIC for several drugs. The MALDI-TOF mass spectrometry analysis indicated the bac- terium isolated as I. limosus, confirmed by 16s rDNA sequence analysis. The described clinical case demonstrates how the bacterial biodiversity in the airways of cystic fibrosis patients is still underestimated. Cystic fibrosis lung represents an ecological niche suitable for growth of a wide variety of unusual bacteria not commonly associated with human diseases, such as I. limosus. Therefore further studies are needed to evaluate the epidemiology and clinical implications of I. limosus in the physiopathology of cystic fibrosis lung infection.


Assuntos
Alphaproteobacteria/isolamento & purificação , Fibrose Cística/microbiologia , Alphaproteobacteria/classificação , Alphaproteobacteria/efeitos dos fármacos , Alphaproteobacteria/genética , Antibacterianos/uso terapêutico , Fibrose Cística/tratamento farmacológico , Humanos , Itália , Masculino , Adulto Jovem
13.
Microorganisms ; 12(3)2024 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-38543488

RESUMO

Grape pomace is the main by-product of vine-winery chains. It requires adequate treatment and disposal but is also an economically underused source of bioactive plant secondary metabolites. This study aimed to investigate the antibacterial effects of polyphenolic extracts from Aglianico (Vitis vinifera L.) grape pomace. In particular, hydroethanolic extracts obtained via an ultrasonic-assisted extraction technique were selected for antimicrobial tests. The extracts were screened for their antibacterial effects against foodborne pathogens that were both Gram-positive, in the case of Staphylococcus aureus and Bacillus cereus, and Gram-negative, in the case of Escherichia coli and Salmonella enterica subsp. enterica serovar Typhimurium, showing variable bacteriostatic and bactericidal effects. In addition, our results demonstrated that the tested grape pomace extracts can reduce the inhibitory concentration of standard antibiotics. Interestingly, selected extracts inhibited biofilm development by S. aureus and B. cereus. Overall, these new insights into the antibacterial properties of grape pomace extracts may represent a relevant step in the design of novel therapeutic tools to tackle foodborne diseases, and in the management of resistant biofilm-related infections.

14.
Front Microbiol ; 15: 1383027, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38711969

RESUMO

The improper use and abuse of antibiotics have led to an increase in multidrug-resistant (MDR) bacteria resulting in a failure of standard antibiotic therapies. To date, this phenomenon represents a leading public health threat of the 21st century which requires alternative strategies to fight infections such as the identification of new molecules active against MDR strains. In the last 20 years, natural extracts with biological activities attracted scientific interest. Following the One Health Approach, natural by-products represent a sustainable and promising alternative solution. Consistently, the aim of the present study was to evaluate the antimicrobial activity of hydro-alcoholic pomegranate peel extract (PPE) against MDR microorganisms belonging to Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp. "ESKAPE" group pathogens. Through semiquantitative and quantitative methods, the PPE showed effective antimicrobial activity against Gram-positive and Gram-negative MDR bacteria. The kinetics of bactericidal action of PPE highlighted that microbial death was achieved in a time- and dose-dependent manner. High concentrations of PPE exhibited antioxidant activity, providing a protective effect on cellular systems and red blood cell membranes. Finally, we report, for the first time, a significant intracellular antibacterial property of PPE as highlighted by its bactericidal action against the staphylococcal reference strain and its bacteriostatic effect against clinical resistant strain in the HeLa cell line. In conclusion, due to its characterized content of polyphenolic compounds and antioxidant activity strength, the PPE could be considered as a therapeutic agent alone or in conjunction with standard antibiotics against challenging infections caused by ESKAPE pathogens.

15.
BioTech (Basel) ; 13(2)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38804294

RESUMO

Bioaerosols and pathogens in indoor workplaces and residential environments are the primary culprits of several infections. Techniques for sanitizing air and surfaces typically involve the use of UV rays or chemical sanitizers, which may release chemical residues harmful to human health. Essential oils, natural substances derived from plants, which exhibit broad antimicrobial properties, could be a viable alternative for air and surface sanitation. The objective of this study has been to investigate the efficacy of thyme essential oil (TEO) in environmental sanitation processes. In Vitro assays through agar well diffusion, disk volatilization and tube dilution methods revealed significant antimicrobial activity of TEO 100% against foodborne and environmental isolates, with both bacteriostatic/fungistatic and bactericidal/fungicidal effects. Therefore, aqueous solutions of TEO 2.5% and 5% were formulated for air sanitation through nebulization and surface disinfection via direct contact. Bioaerosol samples and surface swabs were analyzed before and after sanitation, demonstrating the efficacy of aqueous solutions of TEO in reducing mesophilic and psychrophilic bacteria and environmental fungi levels in both air and on surfaces. The obtained results prove the antimicrobial potential of aqueous solutions of TEO in improving indoor air quality and surface cleanliness, suggesting thyme essential oil as an effective and safe natural sanitizer with minimal environmental impact compared to dangerous chemical disinfectants.

17.
Antibiotics (Basel) ; 12(3)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36978352

RESUMO

Nowadays, the wide spread of foodborne illness and the growing concerns about the use of synthetic food additives have shifted the focus of researchers towards essential oils (EOs) as possible antimicrobials and preservatives of natural origin. Thanks to their antimicrobial properties against pathogenic and food spoilage microorganisms, EOs have shown good potential for use as alternative food additives, also to counteract biofilm-forming bacterial strains, the spread of which is considered to be among the main causes of the increase in foodborne illness outbreaks. In this context, the aim of this study has been to define the antibacterial and antibiofilm profile of thyme (Thymus vulgaris L.) essential oil (TEO) against widespread foodborne pathogens, Salmonella enterica subsp. enterica serovar Typhimurium and Bacillus cereus. TEO chemical composition was analyzed through gas chromatography-mass spectrometry (GC-MS). Preliminary in vitro antibacterial tests allowed to qualitatively verify TEO efficacy against the tested foodborne pathogens. The subsequent determination of minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) values allowed to quantitatively define the bacteriostatic and bactericidal effects of TEO. To evaluate the ability of essential oils to inhibit biofilm formation, a microplate assay was performed for the bacterial biofilm biomass measurement. Results suggest that TEO, rich in bioactive compounds, is able to inhibit the growth of tested foodborne bacteria. In addition, the highlighted in vitro anti-biofilm properties of TEO suggest the use of this natural agent as a promising food preservative to counteract biofilm-related infections in the food industry.

19.
Diagnostics (Basel) ; 12(8)2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35892509

RESUMO

This study provides updated information on the prevalence and co-infections caused by genital microorganisms and pathogens: Mycoplasma genitalium, Mycoplasma hominis, Ureaplasma parvum, Ureaplasma urealyticum, Trichomonas vaginalis, and Gardnerella vaginalis, by retrospectively analyzing a cohort of patients living in the Naples metropolitan area, Campania region, Southern Italy. To investigate the genital infections prevalence in clinical specimens (vaginal/endocervical swabs and urines) collected from infertile asymptomatic women and men from November 2018 to December 2020, we used a multiplex real-time PCR assay. Of the 717 specimens collected, 302 (42.1%) resulted positive for at least one of the targets named above. Statistically significant differences in genital prevalence of selected microorganisms were detected in both women (62.91%) and men (37.08%). G. vaginalis and U. parvum represented the most common findings with an 80.2% and 16.9% prevalence in vaginal/endocervical swabs and first-voided urines, respectively. Prevalence of multiple infections was 18.18% and 8.19% in women and men, respectively. The most frequent association detected was the co-infection of G. vaginalis and U. parvum with 60% prevalence. Our epidemiological analysis suggests different infection patterns between genders, highlighting the need to implement a preventative screening strategy of genital infections to reduce the complications on reproductive organs.

20.
Microorganisms ; 10(12)2022 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-36557699

RESUMO

Foodborne diseases continue to represent an important public health issue. The control of food spoilage and pathogenic microorganisms is achieved mainly by synthetic chemicals, unfortunately associated to several undesirable aspects. The growing requirement for new and safe alternative strategies has resulted in the research of agents from natural sources with antimicrobial properties, such as essential oils (EOs). This study's purpose was to define the antibacterial profile of thyme (Thymus vulgaris) and cloves (Syzygium aromaticum) essential oils against both Gram-positive and Gram-negative important foodborne pathogenic bacteria. Gas chromatography mass spectrometry analysis was performed for EOs' chemical composition. Qualitative in vitro antimicrobial assays (i.e., agar well diffusion method and disk-volatilization method) allowed for verification of the efficacy of EOs, used individually and in binary combination and both in liquid and vapor phase, against Staphylococcus aureus and Escherichia coli food isolates. Minimal inhibitory concentrations and minimal bactericidal concentration values have been used to quantitatively measure the antibacterial activity of EOs, while the fractional inhibitory concentration index has been considered as a predictor of in vitro antibacterial synergistic effects. The microbiological tests suggest that thyme and cloves EOs, rich in bioactive compounds, are able to inhibit the growth of tested foodborne bacteria, especially in vapor phase, also with synergistic effects. Results provide evidence to consider the tested essential oils as promising sources for development of new, broad-spectrum, green food preservatives.

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