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1.
Microorganisms ; 12(4)2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38674752

RESUMO

Several studies have shown fluctuations in the maternal microbiota at various body sites (gut, oral cavity, and vagina). The skin microbiota plays an important role in our health, but studies on the changes during pregnancy are limited. Quantitative and qualitative variations in the skin microbiota in pregnant woman could indeed play important roles in modifying the immune and inflammatory responses of the host. These alterations could induce inflammatory disorders affecting the individual's dermal properties, and could potentially predict infant skin disorder in the unborn. The present study aimed to characterize skin microbiota modifications during pregnancy. For this purpose, skin samples were collected from 52 pregnant women in the first, second, and third trimester of non-complicated pregnancies and from 17 age- and sex-matched healthy controls. The skin microbiota composition was assessed by next generation sequencing (NGS) of the V3-V4 region of the bacterial rRNA 16S. Our results indicate that from the first to the third trimester of pregnancy, changes occur in the composition of the skin microbiota, microbial interactions, and various metabolic pathways. These changes could play a role in creating more advantageous conditions for fetal growth.

2.
BMC Microbiol ; 24(1): 48, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38302874

RESUMO

BACKGROUND: Pediatric chronic intestinal pseudo-obstruction (PIPO) is a rare disease characterized by symptoms and radiological signs suggestive of intestinal obstruction, in the absence of lumen-occluding lesions. It results from an extremely severe impairment of propulsive motility. The intestinal endocrine system (IES) jointly with the enteric nervous system (ENS) regulates secreto-motor functions via different hormones and bioactive messengers/neurotransmitters. The neurotransmitter 5-hydroxytryptamine (5-HT) (or serotonin) is linked to intestinal peristalsis and secretory reflexes. Gut microbiota and its interplay with ENS affect 5-HT synthesis, release, and the subsequent serotonin receptor activation. To date, the interplay between 5-HT and gut microbiota in PIPO remains largely unclear. This study aimed to assess correlations between mucosa associated microbiota (MAM), intestinal serotonin-related genes expression in PIPO. To this purpose, biopsies of the colon, ileum and duodenum have been collected from 7 PIPO patients, and 7 age-/sex-matched healthy controls. After DNA extraction, the MAM was assessed by next generation sequencing (NGS) of the V3-V4 region of the bacterial RNA 16 S, on an Illumina Miseq platform. The expression of genes implicated in serotoninergic pathway (TPH1, SLC6A4, 5-HTR3 and 5-HTR4) was established by qPCR, and correlations with MAM and clinical parameters of PIPO have been evaluated. RESULTS: Our results revealed that PIPO patients exhibit a MAM with a different composition and with dysbiosis, i.e. with a lower biodiversity and fewer less connected species with a greater number of non-synergistic relationships, compared to controls. qPCR results revealed modifications in the expression of serotonin-related intestinal genes in PIPO patients, when compared to controls. Correlation analysis do not reveal any kind of connection. CONCLUSIONS: For the first time, we report in PIPO patients a specific MAM associated to underlying pathology and an altered intestinal serotonin pathway. A possible dysfunction of the serotonin pathway, possibly related to or triggered by an altered microbiota, may contribute to dysmotility in PIPO patients. The results of our pilot study provide the basis for new biomarkers and innovative therapies targeting the microbiota or serotonin pathways in PIPO patients.


Assuntos
Microbioma Gastrointestinal , Pseudo-Obstrução Intestinal , Humanos , Criança , Serotonina/metabolismo , Projetos Piloto , Intestinos , Pseudo-Obstrução Intestinal/genética , Pseudo-Obstrução Intestinal/diagnóstico , Proteínas da Membrana Plasmática de Transporte de Serotonina
3.
Am J Gastroenterol ; 118(11): 2014-2024, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37307528

RESUMO

INTRODUCTION: In the treatment of upper GI endoscopy-negative patients with heartburn and epigastric pain or burning, antacids, antireflux agents, and mucosal protective agents are widely used, alone or as add-on treatment, to increase response to proton-pump inhibitors, which are not indicated in infancy and pregnancy and account for significant cost expenditure. METHODS: In this randomized, controlled, double-blind, double-dummy, multicenter trial assessing the efficacy and safety of mucosal protective agent Poliprotect (neoBianacid, Sansepolcro, Italy) vs omeprazole in the relief of heartburn and epigastric pain/burning, 275 endoscopy-negative outpatients were given a 4-week treatment with omeprazole (20 mg q.d.) or Poliprotect (5 times a day for the initial 2 weeks and on demand thereafter), followed by an open-label 4-week treatment period with Poliprotect on-demand. Gut microbiota change was assessed. RESULTS: A 2-week treatment with Poliprotect proved noninferior to omeprazole for symptom relief (between-group difference in the change in visual analog scale symptom score: [mean, 95% confidence interval] -5.4, -9.9 to -0.1; -6.2, -10.8 to -1.6; intention-to-treat and per-protocol populations, respectively). Poliprotect's benefit remained unaltered after shifting to on-demand intake, with no gut microbiota variation. The initial benefit of omeprazole was maintained against significantly higher use of rescue medicine sachets (mean, 95% confidence interval: Poliprotect 3.9, 2.8-5.0; omeprazole 8.2, 4.8-11.6) and associated with an increased abundance of oral cavity genera in the intestinal microbiota. No relevant adverse events were reported in either treatment arm. DISCUSSION: Poliprotect proved noninferior to standard-dose omeprazole in symptomatic patients with heartburn/epigastric burning without erosive esophagitis and gastroduodenal lesions. Gut microbiota was not affected by Poliprotect treatment. The study is registered in Clinicaltrial.gov (NCT03238534) and the EudraCT database (2015-005216-15).


Assuntos
Antiulcerosos , Dispepsia , Esofagite , Úlcera Péptica , Humanos , Omeprazol/uso terapêutico , Azia/tratamento farmacológico , Azia/etiologia , Antiulcerosos/uso terapêutico , Esofagite/induzido quimicamente , Inibidores da Bomba de Prótons/uso terapêutico , Dispepsia/tratamento farmacológico , Úlcera Péptica/complicações , Dor Abdominal/tratamento farmacológico , Resultado do Tratamento , Método Duplo-Cego
4.
Front Med (Lausanne) ; 9: 921675, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35872763

RESUMO

Rheumatoid Arthritis (RA) is a chronic systemic autoimmune disease. Modifications of gut microbiota seem to be associated with the disease, but the impact of gut microbiota on therapies' outcome remains unclear. A role of T cells in RA pathogenesis has been addressed, particularly on the Th17/Treg cells balance. Our study aimed to evaluate in early RA (ERA) patients compared to a control group, fecal gut microbiota composition, short-chain fatty acids concentrations, and the levels of circulating Th17/Treg and their own cytokines, before and after 3 months of standard treatment (Methotrexate (MTX) plus glucocorticoids). Fecal microbiota characterization was carried out on 19 ERA patients and 20 controls matched for sex and age. Significant decreased biodiversity levels, and a partition on the base of the microbiota composition, between the ERA patients at baseline compared to controls, were observed. The co-occurrent analysis of interactions revealed a characteristic clustered structure of the microbial network in controls that is lost in ERA patients where an altered connection between microbes and clinical parameters/metabolites has been reported. Microbial markers such as Acetanaerobacterium elongatum, Cristiansella massiliensis, and Gracilibacter thermotolerans resulted significantly enriched in control group while the species Blautia gnavus emerged to be more abundant in ERA patients. Our results showed an alteration in Th17/Treg balance with higher Th17 levels and lower Treg levels in ERA group respect to control at baseline, those data improved after therapy. Treatment administration and the achievement of a low disease activity/remission appear to exert a positive pressure on the structure of intestinal microbiota with the consequent restoration of biodiversity, of the structure of microbial network, and of the abundance of taxa that became closer to those presented by the subject without the disease. We also found an association between Blautia gnavus and ERA patients characterized by a significant reduction of propionic acid level. Furthermore significant differences highlighted at baseline among controls and ERA patients are no more evident after treatment. These data corroborate the role played by gut microbiota in the disease and suggest that therapy aimed to restore gut microbiota would improve treatment outcome.

5.
Molecules ; 27(9)2022 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-35566306

RESUMO

The aim of this work was to optimize and characterize nanocomposite films based on gellan gum methacrylate (GG-MA) and silver nanoparticles (AgNPs) for application in the field of wound dressing. The films were produced using the solvent casting technique coupled with a photocuring process. The UV irradiation of GG-MA solutions containing glycerol as a plasticizer and different amounts of silver nitrate resulted in the concurrent crosslinking of the photocurable polymer and a reduction of Ag ions with consequent in situ generation of AgNPs. In the first part of the work, the composition of the films was optimized, varying the concentration of the different components, the GG-MA/glycerol and GG-MA/silver nitrate weight ratios as well as the volume of the film-forming mixture. Rheological analyses were performed on the starting solutions, whereas the obtained films were characterized for their mechanical properties. Colorimetric analyses and swelling studies were also performed in order to determine the AgNPs release and the water uptake capacity of the films. Finally, microbiological tests were carried out to evaluate the antimicrobial efficacy of the optimized films, in order to demonstrate their possible application as dressings for the treatment of infected hard-to-heal wounds, which is a demanding task for public healthcare.


Assuntos
Nanopartículas Metálicas , Nanocompostos , Antibacterianos , Bandagens , Glicerol , Prata , Nitrato de Prata , Solventes
6.
Oncol Lett ; 23(4): 132, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35261640

RESUMO

Violacein is a natural pigment, a pyrrolidone, and a bisindole derived from the condensation of two tryptophan molecules, which gives a blue violet color to several gram-negative violacein-producing bacteria. Violacein production provides a competitive advantage against antagonistic species or predators. In addition, the compound has antibacterial, antifungal, antiviral, and antioxidant activities. Several studies on colon, breast, and head and neck cancer lines have already demonstrated the anti-proliferative potential of violacein. Bladder cancer is one of the most common types of cancer in urology. The therapeutic approach is mainly based on surgery, chemotherapy, and immunotherapy. The aim of the present study was to evaluate the anti-proliferative activity of violacein against the human bladder cancer cell lines, HTB4 (T24) and HTB9 (5637), using low-grade and high-grade transitional cell carcinoma models, respectively, which has never been assayed before. For this purpose, the potential violacein anti-proliferative effect on T24 and 5637 cells was evaluated by studying the cell viability, proliferation, cell cycle, and caspase-3 activation. The results showed that violacein had anti-proliferative activity in the two cell lines, which was greater for the second-stage bladder cancer cell line (5637), and a different mode of action against the two cell lines.

7.
Microorganisms ; 9(12)2021 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-34946150

RESUMO

Chronic intestinal pseudo-obstruction (CIPO) is a rare clinical syndrome characterized by severe impairment of gastrointestinal (GI) motility, and its symptoms are suggestive of partial or complete intestinal obstruction in the absence of any lesion restricting the intestinal lumen. Diagnosis and therapy of CIPO patients still represent a significant challenge for clinicians, despite their efforts to improve diagnostic workup and treatment strategies for this disease. The purpose of this review is to better understand what is currently known about the relationship between CIPO patients and intestinal microbiota, with a focus on the role of the enteric nervous system (ENS) and the intestinal endocrine system (IES) in intestinal motility, underling the importance of further studies to deeply understand the causes of gut motility dysfunction in these patients.

8.
Sleep Med ; 87: 1-7, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34479058

RESUMO

Sleep plays a fundamental role in maintaining good psycho-physical health, it can influence hormone levels, mood, and weight. Recent studies, focused on the interconnection between intestinal microbiome and sleep disorders, have shown the growing importance of a healthy and balanced intestinal microbiome for the hosts health. Normally, gut microbiota and his host are linked by mutualistic relationship, that in some conditions, can be compromised by shifts in microbiota's composition, called dysbiosis. Both sleep problems and dysbiosis of the gut microbiome can lead to metabolic disorders and, in this review, we will explore what is present in literature on the link between sleep pathologies and intestinal dysbiosis.


Assuntos
Microbioma Gastrointestinal , Doenças Metabólicas , Transtornos do Sono-Vigília , Disbiose/complicações , Humanos
9.
Artigo em Inglês | MEDLINE | ID: mdl-32962009

RESUMO

BACKGROUND: Wastewater treatment plants (WWTPs) are microbial factories aimed to reduce the amount of nutrients and pathogenic microorganisms in the treated wastewater before its discharge into the environment. We studied the impact of urban WWTP effluents on the abundance of antibiotic resistance genes (ARGs) and antibiotic-resistant Escherichia coli (AR-E. coli) in the last stretch of two rivers (Arrone and Tiber) in Central Italy that differ in size and flow volume. METHODS: Water samples were collected in three seasons upstream and downstream of the WWTP, at the WWTP outlet, and at sea sites near the river mouth, and analyzed for the abundance of ARGs by qPCR and AR-E. coli using cultivation followed by disk diffusion assays. RESULTS: For all studied genes (16S rRNA, intI1, sul1, ermB, blaTEM, tetW and qnrS), absolute concentrations were significantly higher in the Tiber than in the Arrone at all sampling sites, despite their collection date, but the prevalence of target ARGs within bacterial communities in both rivers was similar. The absolute concentrations of most ARGs were also generally higher in the WWTP effluent with median levels between log 4 and log 6 copies per ml but did not show differences along the studied stretches of rivers. Statistically significant site effect was found for E. coli phenotypic resistance to tetracycline and ciprofloxacin in the Arrone but not in the Tiber. CONCLUSIONS: In both rivers, diffuse or point pollution sources other than the studied WWTP effluents may account for the observed resistance pattern, although the Arrone appears as more sensitive to the wastewater impact considering its lower flow volume.


Assuntos
Resistência Microbiana a Medicamentos , Escherichia coli , Genes Bacterianos , Águas Residuárias , Antibacterianos , Resistência Microbiana a Medicamentos/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Itália , RNA Ribossômico 16S , Águas Residuárias/análise
10.
Artigo em Inglês | MEDLINE | ID: mdl-32760681

RESUMO

Microbiota are microorganismal communities colonizing human tissues exposed to the external environment, including the urogenital tract. The bacterial composition of the vaginal microbiota has been established and is partially related to obstetric outcome, while the uterine microbiota, considered to be a sterile environment for years, is now the focus of more extensive studies and debates. The characterization of the microbiota contained in the reproductive tract (RT) of asymptomatic and infertile women, could define a specific RT microbiota associated with implantation failure. In this pilot study, 34 women undergoing personalized hormonal stimulation were recruited and the biological samples of each patient, vaginal fluid, and endometrial biopsy, were collected immediately prior to oocyte-pick up, and sequenced. Women were subsequently divided into groups according to fertilization outcome. Analysis of the 16s rRNA V4-V5 region revealed a significant difference between vaginal and endometrial microbiota. The vaginal microbiota of pregnant women corroborated previous data, exhibiting a lactobacilli-dominant habitat compared to non-pregnant cases, while the endometrial bacterial colonization was characterized by a polymicrobial ecosystem in which lactobacilli were exclusively detected in the group that displayed unsuccessful in vitro fertilization. Overall, these preliminary results revisit our knowledge of the genitourinary microbiota, and highlight a putative relationship between vaginal/endometrial microbiota and reproductive success.


Assuntos
Infertilidade Feminina , Microbiota , Feminino , Humanos , Projetos Piloto , Gravidez , RNA Ribossômico 16S/genética , Vagina
11.
Nutrients ; 12(8)2020 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-32731403

RESUMO

The gut microbiota is a complex microbial ecosystem that coexists with the human organism in the intestinal tract. The members of this ecosystem live together in a balance between them and the host, contributing to its healthy state. Stress, aging, and antibiotic therapies are the principal factors affecting the gut microbiota composition, breaking the mutualistic relationship among microbes and resulting in the overgrowth of potential pathogens. This condition, called dysbiosis, has been linked to several chronic pathologies. In this review, we propose the use of the predator Bdellovibrio bacteriovorus as a possible probiotic to prevent or counteract dysbiotic outcomes and look at the findings of previous research.


Assuntos
Bdellovibrio bacteriovorus , Disbiose/microbiologia , Disbiose/terapia , Microbioma Gastrointestinal , Probióticos/uso terapêutico , Ecossistema , Trato Gastrointestinal/microbiologia , Humanos , Simbiose
12.
Microorganisms ; 8(5)2020 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-32414211

RESUMO

Respiratory Syncytial Virus (RSV) is the leading cause of bronchiolitis, and the severity may be influenced by the bacterial ecosystem. Our aim was to analyze the nasal microbiota from 48 infants affected by bronchiolitis from RSV virus and 28 infants with bronchiolitis but negative for the virus. Results showed a significantly lower biodiversity in the RSV-positive group with respect to the RSV-negative group, a specific microbial profile associated with the RSV-positive group different from that observed in the negative group, and significant modifications in the relative abundance of taxa in the RSV-positive group, as well as in the RSV-A group, with respect to the negative group. Furthermore, microbial network analyses evidenced, in all studied groups, the presence of two predominant sub-networks characterized by peculiar inter- and intra-group correlation patterns as well as a general loss of connectivity among microbes in the RSV-positive group, particularly in the RSV-A group. Our results indicated that infants with more severe bronchiolitis disease, caused by RSV-A infection, present significant perturbations of both the nasal microbiota structure and the microbial relationships. Patients with a milder bronchiolitis course (RSV-B-infected and patients who have cleared the virus) presented less severe alterations.

14.
Microorganisms ; 8(1)2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31861852

RESUMO

In Crohn's disease (CD) patients, intestinal dysbiosis with an overgrowth of Proteobacteria, mainly Escherichia coli, has been reported. A new pathotype of E. coli, the adherent-invasive Escherichia coli strain (AIEC), has been isolated from the mucosae of CD patients. AIEC strains play an important role in CD pathogenesis, increasing intestinal mucosa damage and inflammation. Several studies have been undertaken to find possible strategies/treatments aimed at AIEC strain reduction/elimination from CD patients' intestinal mucosae. To date, a truly effective strategy against AIEC overgrowth is not yet available, and as such, further investigations are warranted. Bdellovibrio bacteriovorus is a predator bacterium which lives by invading Gram-negative bacteria, and is usually present both in natural and human ecosystems. The aim of this study was to evaluate a novel possible strategy to treat CD patients' mucosae when colonized by AIEC strains, based on the utilization of the Gram-negative predatory bacteria, B. bacteriovorus. The overall results indicate that B. bacteriovorus is able to interfere with important steps in the dynamics of pathogenicity of AIEC strains by its predatory activity. We indicate, for the first time, the possibility of counteracting AIEC strain overgrowth by exploiting what naturally occurs in microbial ecosystems (i.e., predation).

15.
New Microbiol ; 42(4): 221-224, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31609455

RESUMO

This short communication reports the preliminary results of Fecal Microbial Transplantation (FMT) impact on microbiota, microbial translocation (MT), and immune activation in four recurrent Clostridium difficile infection (R-CDI) patients. After FMT a restore of gut microbiota composition with a significant increase of fecal acetyl-putrescine and spermidine and fecal acetate and butyrate, a decrease of immune activation of T cells CD4+ and CD8+levels, and of LPS binding protein (LBP) level, were observed. Preliminary results indicate that FMT seems to be helpful not only as a CDI radical cure, with an impact on fecal microbiota and metabolome profiles, but also on MT and immune activation.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Transplante de Microbiota Fecal , Microbioma Gastrointestinal , Metaboloma , Linfócitos T , Idoso , Idoso de 80 Anos ou mais , Infecções por Clostridium/imunologia , Infecções por Clostridium/microbiologia , Infecções por Clostridium/terapia , Fezes/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Linfócitos T/imunologia , Resultado do Tratamento
16.
Artigo em Inglês | MEDLINE | ID: mdl-30087270

RESUMO

A microbial ecosystem in which bacteria no longer live in a mutualistic association is called dysbiotic. Gut microbiota dysbiosis is a condition related with the pathogenesis of intestinal illnesses (irritable bowel syndrome, celiac disease, and inflammatory bowel disease) and extra-intestinal illnesses (obesity, metabolic disorder, cardiovascular syndrome, allergy, and asthma). Dysbiosis status has been related to various important pathologies, and many therapeutic strategies aimed at restoring the balance of the intestinal ecosystem have been implemented. These strategies include the administration of probiotics, prebiotics, and synbiotics; phage therapy; fecal transplantation; bacterial consortium transplantation; and a still poorly investigated approach based on predatory bacteria. This review discusses the various aspects of these strategies to counteract intestinal dysbiosis.


Assuntos
Disbiose/prevenção & controle , Microbioma Gastrointestinal , Disbiose/microbiologia , Transplante de Microbiota Fecal , Humanos , Consórcios Microbianos , Terapia por Fagos , Prebióticos/administração & dosagem , Probióticos/administração & dosagem , Probióticos/uso terapêutico , Simbióticos/administração & dosagem
17.
Sci Rep ; 8(1): 8210, 2018 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-29844325

RESUMO

In liver cirrhosis (LC), impaired intestinal functions lead to dysbiosis and possible bacterial translocation (BT). Bacteria or their byproducts within the bloodstream can thus play a role in systemic inflammation and hepatic encephalopathy (HE). We combined 16S sequencing, NMR metabolomics and network analysis to describe the interrelationships of members of the microbiota in LC biopsies, faeces, peripheral/portal blood and faecal metabolites with clinical parameters. LC faeces and biopsies showed marked dysbiosis with a heightened proportion of Enterobacteriaceae. Our approach showed impaired faecal bacterial metabolism of short-chain fatty acids (SCFAs) and carbon/methane sources in LC, along with an enhanced stress-related response. Sixteen species, mainly belonging to the Proteobacteria phylum, were shared between LC peripheral and portal blood and were functionally linked to iron metabolism. Faecal Enterobacteriaceae and trimethylamine were positively correlated with blood proinflammatory cytokines, while Ruminococcaceae and SCFAs played a protective role. Within the peripheral blood and faeces, certain species (Stenotrophomonas pavanii, Methylobacterium extorquens) and metabolites (methanol, threonine) were positively related to HE. Cirrhotic patients thus harbour a 'functional dysbiosis' in the faeces and peripheral/portal blood, with specific keystone species and metabolites related to clinical markers of systemic inflammation and HE.


Assuntos
Translocação Bacteriana , Amplificação de Genes , Encefalopatia Hepática/metabolismo , Inflamação/metabolismo , Cirrose Hepática/metabolismo , Metabolômica , Microbiota , Carbono/metabolismo , Ácidos Graxos/metabolismo , Fezes/microbiologia , Encefalopatia Hepática/microbiologia , Humanos , Cirrose Hepática/microbiologia , Metagenômica , Metano/metabolismo , Microbiota/genética , RNA Ribossômico 16S/genética
18.
New Microbiol ; 41(2): 145-152, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29498744

RESUMO

The present study aimed to characterize the behavior of Bdellovibrio bacteriovorus in the presence of Staphylococcus aureus. B. bacteriovorus was co-cultured with S. aureus or Pseudomonas aeruginosa or Streptococcus mutans, in planktonic and sessile conditions. Co-cultures were studied by Field-Emission Scanning Electron Microscopy (FESEM), Scanning Transmission Electron Microscopy (STEM), turbidimetry, quantitative PCR (qPCR), and sequencing of gene Bd0108 of B. bacteriovorus. Results indicated that B. bacteriovorus comparably inhibited planktonic growth of P. aeruginosa and S. aureus, but not of S. mutans. FESEM and STEM showed that B. bacteriovorus interacts with S. aureus affecting its cell wall and membrane. Sequencing of gene Bd0108 did not reveal any of the mutations that can arise from the host-interaction (hit) locus. Although some Gram-negative species are reported to be B. bacteriovorus prey, it seems that in case of nutrient deficiency this predatory bacterium can also take advantage of some Gram-positive species. B. bacteriovorus behaviour in the presence of S. aureus is relevant for its possible therapeutic use in several pathologies, like cystic fibrosis in which S. aureus and P. aeruginosa frequently coexist as infectious agents.


Assuntos
Bdellovibrio bacteriovorus/fisiologia , Pseudomonas aeruginosa/virologia , Staphylococcus aureus/virologia , Streptococcus mutans/virologia , Técnicas de Cocultura , Microscopia Eletrônica de Varredura
19.
Ann Stomatol (Roma) ; 8(2): 59-70, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29299190

RESUMO

AIMS: The present study aimed to investigate microbial patterns associated with disease progression and coinfection by different Herpesviruses in generalized aggressive periodontitis (GAP). METHODS: Microbiological samples were obtained from active (AS) and non-active (n-AS) sites in 165 subjects affected by GAP and were analyzed for 40 bacterial species by the Checkerboard DNA-DNA Hybridization technique and for Herpes simplex 1 (HSV-1), Human Cytomegalovirus (CMV), and Epstein Bar virus (EBV) by PCR.Common Factor Analysis and Multiple Regression Analysis were applied to disclose specific microbial patterns associated with the three viruses. RESULTS: Herpesviruses were detected in 37.6% of subjects. Detection of each of the searched viruses was associated with specific patterns of subgingival biofilm in AS. Logistic regression analyses evidenced several virus/bacteria associations: i) EBV with Aggregatibacter actinomycetemcomitans; ii) CMV with A. actinomycetemcomitans, Veillonella parvula, Parvimonas micra and Fusobacterium nucleatum subsp. polymorphum; iii) HSV-1 with Porphyromonas gingivalis, Tannerella forsythia, Fusobacterium periodonticum and Staphylococcus aureus. CONCLUSIONS: Microbiological data suggest that Herpesviruses are probably not mere spectators of disease progression and that specific patterns of subgingival plaque are correlated with the presence of different Herpesviruses.

20.
N Biotechnol ; 37(Pt A): 80-89, 2017 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-27576102

RESUMO

Although in recent years several methods have been studied and developed to obtain different types of nanosized drug delivery systems, the set up of suitable procedures and materials remains highly expensive, their preparation is time consuming and often not feasible for a scale-up process. Furthermore, the sterilisation and storage of nanocarrier formulations represents a complicated but mandatory step for their effective use. In our previous work we assessed the use of an autoclaving process to achieve, in one simple step, sterile self-assembled hyaluronan-cholesterol (HA-CH) and hyaluronan-riboflavin (HA-Rfv) nanohydrogels (NHs). In the present work, the effect of the high temperature on HA-CH has been studied in detail. HA-CH suspensions were characterised in terms of size and polydispersity by Dynamic Light Scattering at different temperatures and conditions; the HA-CH chemical structure and its molecular weight were assessed via FT-IR and GPC analysis after the sterilising cycle in an autoclave at 121°C for 20min. The obtained NHs were then observed with TEM and AFM microscopy, in both dry and liquid conditions. The Young's modulus of the NHs was determined, evidencing the soft nature of these nanosystems; the critical aggregation concentration (c.a.c) of the nanosuspension was also assessed. Thereafter, alginate lyase (AL) was conjugated to NHs, with the aim of developing a useful system for therapies against bacterial infections producing alginate biofilms. The conjugation efficiency and the enzymatic activity of AL were determined after immobilisation. The AL-NHs system showed the ability to depolymerise alginate, offering an opportunity to be a useful nanosystem for the treatment of biofilm-associated infections.


Assuntos
Portadores de Fármacos/química , Nanoestruturas/química , Polissacarídeo-Liases/administração & dosagem , Alginatos/metabolismo , Infecções Bacterianas/metabolismo , Infecções Bacterianas/microbiologia , Infecções Bacterianas/terapia , Biofilmes , Biotecnologia , Colesterol/química , Sistemas de Liberação de Medicamentos , Humanos , Ácido Hialurônico/química , Hidrogéis , Nanoestruturas/ultraestrutura , Polissacarídeo-Liases/metabolismo
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