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1.
Liver Int ; 43(2): 370-380, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36287108

RESUMO

BACKGROUND AND AIMS: Hypercholesterolemia is frequent in people with primary biliary cholangitis (PBC); however, it does not seem to confer an increased risk of cardiovascular disease. We aimed to evaluate the prevalence of peripheral arterial disease in PBC women and its association with the gut-liver axis and systemic inflammation. METHODS: Thirty patients affected by PBC and hypercholesterolemia were enrolled, with equal-sized groups of women with non-alcoholic fatty liver disease (NAFLD) and healthy controls (CTRL). All patients underwent Doppler ultrasound examination of peripheral arteries, assessment of flow-mediated dilation, quantification of circulating cytokines and vasoactive mediators and characterization of the gut microbiota. RESULTS: PBC patients had a higher prevalence of lower extremity arterial disease (LEAD) defined as atherosclerotic plaques in any of femoral, popliteal and/or tibial arteries compared with both NAFLD and CTRL women (83.3% vs. 53.3% and 50%, respectively; p = .01). Factors associated with LEAD at univariate analysis were VCAM-1 (p = .002), ICAM-1 (p = .003), and TNF-alpha (p = .04) serum levels, but only VCAM-1 (OR 1.1, 95% CI 1.0-1.1; p = .04) and TNF-alpha (OR 1.12, 95% CI 0.99-1.26; p = .04) were confirmed as independent predictors in the multivariate model. Gut microbiota analysis revealed that Acidaminococcus (FDR = 0.0008), Bifidobacterium (FDR = 0.001) and Oscillospira (FDR = 0.03) were differentially expressed among groups. Acidaminococcus, which was increased in PBC, was positively correlated with TNF-alpha serum levels. Down-regulation of metabolic pathways linked to fatty acid and butyrate metabolism, glyoxylate metabolism and branched-chain amino acids degradation was found in the functional gut metagenome of PBC women. CONCLUSIONS: LEAD is common in patients affected by PBC and is associated with inflammatory markers and alterations in the gut-liver axis.


Assuntos
Aterosclerose , Hipercolesterolemia , Cirrose Hepática Biliar , Hepatopatia Gordurosa não Alcoólica , Humanos , Feminino , Cirrose Hepática Biliar/complicações , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Fator de Necrose Tumoral alfa , Hipercolesterolemia/complicações , Prevalência , Molécula 1 de Adesão de Célula Vascular , Aterosclerose/epidemiologia , Aterosclerose/complicações , Extremidade Inferior
2.
Liver Int ; 41(6): 1320-1334, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33713524

RESUMO

BACKGROUND & AIM: Sarcopenia is frequent in cirrhosis and is associated with unfavourable outcomes. The role of the gut-liver-muscle axis in this setting has been poorly investigated. The aim of this study was to identify gut microbiota, metabolic and inflammatory signatures associated with sarcopenia in cirrhotic patients. METHODS: Fifty cirrhotic patients assessed for the presence of sarcopenia by the quantification of muscle mass and strength were compared with age- and sex-matched controls. A multiomic analysis, including gut microbiota composition and metabolomics, serum myokines and systemic and intestinal inflammatory mediators, was performed. RESULTS: The gut microbiota of sarcopenic cirrhotic patients was poor in bacteria associated with physical function (Methanobrevibacter, Prevotella and Akkermansia), and was enriched in Eggerthella, a gut microbial marker of frailty. The abundance of potentially pathogenic bacteria, such as Klebsiella, was also increased, to the detriment of autochthonous ones. Sarcopenia was associated with elevated serum levels of pro-inflammatory mediators and of fibroblast growth factor 21 (FGF21) in cirrhotic patients. Gut microbiota metabolic pathways involved in amino acid, protein and branched-chain amino acid metabolism were up-regulated, in addition to ethanol, trimethylamine and dimethylamine production. Correlation networks and clusters of variables associated with sarcopenia were identified, including one centred on Klebsiella/ethanol/FGF21/Eggerthella/Prevotella. CONCLUSIONS: Alterations in the gut-liver-muscle axis are associated with sarcopenia in patients with cirrhosis. Detrimental but also compensatory functions are involved in this complex network.


Assuntos
Fragilidade , Microbioma Gastrointestinal , Sarcopenia , Humanos , Cirrose Hepática/complicações
3.
Hepatology ; 69(1): 107-120, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-29665135

RESUMO

The gut-liver axis plays a pivotal role in the pathogenesis of nonalcoholic fatty liver disease (NAFLD), which is the third leading cause of hepatocellular carcinoma (HCC) worldwide. However, the link between gut microbiota and hepatocarcinogenesis remains to be clarified. The aim of this study was to explore what features of the gut microbiota are associated with HCC in patients with cirrhosis and NAFLD. A consecutive series of patients with NAFLD-related cirrhosis and HCC (group 1, 21 patients), NAFLD-related cirrhosis without HCC (group 2, 20 patients), and healthy controls (group 3, 20 patients) was studied for gut microbiota profile, intestinal permeability, inflammatory status, and circulating mononuclear cells. We finally constructed a model depicting the most relevant correlations among these features, possibly involved in hepatocarcinogenesis. Patients with HCC showed increased levels of fecal calprotectin, while intestinal permeability was similar to patients with cirrhosis but without HCC. Plasma levels of interleukin 8 (IL8), IL13, chemokine (C-C motif) ligand (CCL) 3, CCL4, and CCL5 were higher in the HCC group and associated with an activated status of circulating monocytes. The fecal microbiota of the whole group of patients with cirrhosis showed higher abundance of Enterobacteriaceae and Streptococcus and a reduction in Akkermansia. Bacteroides and Ruminococcaceae were increased in the HCC group, while Bifidobacterium was reduced. Akkermansia and Bifidobacterium were inversely correlated with calprotectin concentration, which in turn was associated with humoral and cellular inflammatory markers. A similar behavior was also observed for Bacteroides. Conclusion: Our results suggest that in patients with cirrhosis and NAFLD the gut microbiota profile and systemic inflammation are significantly correlated and can concur in the process of hepatocarcinogenesis.


Assuntos
Carcinoma Hepatocelular/congênito , Carcinoma Hepatocelular/microbiologia , Microbioma Gastrointestinal , Inflamação/complicações , Cirrose Hepática/complicações , Neoplasias Hepáticas/complicações , Neoplasias Hepáticas/microbiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Liver Int ; 40(4): 878-888, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31951082

RESUMO

BACKGROUND & AIMS: Alcohol use disorder (AUD) represents the most common cause of liver disease. The gut microbiota plays a critical role in the progression of alcohol-related liver damage. Aim of this study was to characterize the gut microbial composition and function in AUD patients with alcohol-associated liver disease (AALD). METHODS: This study included 36 AUD patients (14 with cirrhosis) who were active drinkers and an equal number of matched controls. Stool microbial composition, serum levels of lipopolysaccharide, cytokines/chemokines and gut microbiota functional profile were assessed. RESULTS: AUD patients had a decreased microbial alpha diversity as compared to controls (0.092 vs 0.130, P = .047) and a specific gut microbial signature. The reduction of Akkermansia and the increase in Bacteroides were able to identify AUD patients with an accuracy of 93.4%. Serum levels of lipopolysaccharide (4.91 vs 2.43, P = .009) and pro-inflammatory mediators (tumour necrosis factor alpha 60.85 vs 15.08, P = .001; interleukin [IL] 1beta 4.43 vs 1.72, P = .0001; monocyte chemoattractant protein 1 225.22 vs 16.43, P = .006; IL6 1.87 vs 1.23, P = .008) were significantly increased in AUD patients compared to controls and in cirrhotic patients compared to non-cirrhotic ones (IL6 3.74 vs 1.39, P = .019; IL8 57.60 vs 6.53, P = .004). The AUD-associated gut microbiota showed an increased expression of gamma-aminobutyric acid (GABA) metabolic pathways and energy metabolism. CONCLUSIONS: AUD patients present a specific gut microbial fingerprint, associated with increased endotoxaemia, systemic inflammatory status and functional alterations that may be involved in the progression of the AALD and in the pathogenesis of AUD.


Assuntos
Alcoolismo , Microbioma Gastrointestinal , Hepatopatias Alcoólicas , Alcoolismo/complicações , Fezes , Humanos , Cirrose Hepática
5.
Clin Exp Rheumatol ; 38 Suppl 125(3): 73-84, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32865168

RESUMO

OBJECTIVES: Systemic sclerosis (SSc) is a rare multi-organ disorder with a prominent gastrointestinal (GI) involvement. Altered gut microbiota is now considered a pivotal factor associated with the development of immune-mediated and inflammatory diseases. We performed a 16S ribosomal RNA (rRNA) gene-sequencing analysis of fecal microbiota in a cohort of SSc patients and matched healthy controls (HCs), with the aim to obtain some hints about a possible role of dysbiosis in the onset, progression, and severity of the disease. METHODS: We analysed stool samples from 63 SSc patients with different disease duration, phenotype, and nutritional status and from 17 HCs through 16S ribosomal RNA (rRNA) gene-sequencing. RESULTS: Microbial richness was lower for patients with long-standing disease. A similar observation was made for patients with diffuse cutaneous SSc (dsSSc) compared to those with limited variant (lcSSc) and for patients who reported a recent weight loss. Consistent with previous reports, we noted a deviation of the intestinal microbial composition in patients with SSc compared to HCs, with a greater expression of Lactobacillus and Streptococcus and a depletion of Sutterella. Nutritional status, assessed using BMI as a surrogate, appeared to have a marked impact on the gut microbiota, with overweight patients showing lower richness compared both to underweight and normal-BMI patients. CONCLUSIONS: Our findings expand the current knowledge of gut microbiota in SSc and could be useful to identify patients who would most benefit from treatments aimed at restoring the eu-biosis.


Assuntos
Microbioma Gastrointestinal , Escleroderma Sistêmico , Disbiose , Fezes , Humanos , Estado Nutricional , RNA Ribossômico 16S
6.
Alcohol Clin Exp Res ; 42(12): 2313-2325, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30320890

RESUMO

BACKGROUND: There is strong evidence that alcoholism leads to dysbiosis in both humans and animals. However, it is unclear how changes in the intestinal microbiota (IM) relate to ethanol (EtOH)-induced disruption of gut-liver homeostasis. We investigated this issue using selectively bred Sardinian alcohol-preferring (sP) rats, a validated animal model of excessive EtOH consumption. METHODS: Independent groups of male adult sP rats were exposed to the standard, home-cage 2-bottle "EtOH (10% v/v) versus water" choice regimen with unlimited access for 24 h/d (Group Et) for 3 (T1), 6 (T2), and 12 (T3) consecutive months. Control groups (Group Ct) were composed of matched-age EtOH-naïve sP rats. We obtained samples from each rat at the end of each experimental time, and we used blood and colon tissues for intestinal barrier integrity and/or liver pathology assessments and used stool samples for IM analysis with 16S ribosomal RNA gene sequencing. RESULTS: Rats in Group Et developed hepatic steatosis and elevated serum transaminases and endotoxin/lipopolysaccharide (LPS) levels but no other liver pathological changes (i.e., necrosis/inflammation) or systemic inflammation. While we did not find any apparent alteration of the intestinal colonic mucosa, we found that rats in Group Et exhibited significant changes in IM composition compared to the rats in Group Ct. These changes were sustained throughout T1, T2, and T3. In particular, Ruminococcus, Coprococcus, and Streptococcus were the differentially abundant microbial genera at T3. The KEGG Ortholog profile revealed that IM functional modules, such as biosynthesis, transport, and export of LPS, were also enriched in Group Et rats at T3. CONCLUSIONS: We showed that chronic, voluntary EtOH consumption induced liver injury and endotoxemia together with dysbiotic changes in sP rats. This work sets the stage for improving our knowledge of the prevention and treatment of EtOH-related diseases.


Assuntos
Consumo de Bebidas Alcoólicas/psicologia , Endotoxemia/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Hepatopatias Alcoólicas/microbiologia , Consumo de Bebidas Alcoólicas/genética , Animais , Colo/microbiologia , Fígado Gorduroso Alcoólico/microbiologia , Fígado Gorduroso Alcoólico/patologia , Intestinos/patologia , Lipopolissacarídeos/sangue , Fígado/patologia , Testes de Função Hepática , Masculino , RNA Ribossômico 16S , Ratos , Transaminases/sangue
7.
Dig Dis ; 36(1): 56-65, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-28683448

RESUMO

Few data exist on differences in gut microbiota composition among principal gastrointestinal (GI) diseases. We evaluated the differences in gut microbiota composition among uncomplicated diverticular disease (DD), irritable bowel syndrome (IBS) and inflammatory bowel diseases (IBD) patients. DD, IBS, and IBD patients along with healthy controls (CT) were enrolled in our Italian GI outpatient clinic. Stool samples were collected. Microbiota composition was evaluated through a metagenomic gene-targeted approach. GI pathology represented a continuous spectrum of diseases where IBD displayed one extreme, while CT displayed the other. Among Phyla, Biplot PC2/PC3 and dendogram plot showed major differences in samples from IBS and IBD. DD resembled species CT composition, but not for Bacteroides fragilis. In IBS, Dialister spp. and then Faecalibacterium prausnitzii were the most representative species. Ulcerative colitis showed a reduced concentration of Clostridium difficile and an increase of Bacteroides fragilis. In Crohn's disease, Parabacteroides distasonis was the most represented, while Faecalibacterium prausnitzii and Bacteroides fragilis were significantly reduced. Each disorder has its definite overall microbial signature, which produces a clear differentiation from the others. On the other hand, shared alterations constitute the "core dysbiosis" of GI diseases. The assessment of these microbial markers represents a parameter that may complete the diagnostic assessment.


Assuntos
Biomarcadores/metabolismo , Doenças Diverticulares/microbiologia , Microbioma Gastrointestinal , Saúde , Doenças Inflamatórias Intestinais/microbiologia , Síndrome do Intestino Irritável/microbiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Análise de Componente Principal , Especificidade da Espécie
8.
Appl Environ Microbiol ; 82(22): 6633-6644, 2016 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-27590821

RESUMO

Besides being part of anti-Helicobacter pylori treatment regimens, proton pump inhibitors (PPIs) are increasingly being used to treat dyspepsia. However, little is known about the effects of PPIs on the human gastric microbiota, especially those related to H. pylori infection. The goal of this study was to characterize the stomach microbial communities in patients with dyspepsia and to investigate their relationships with PPI use and H. pylori status. Using 16S rRNA gene pyrosequencing, we analyzed the mucosa-associated microbial populations of 24 patients, of whom 12 were treated with the PPI omeprazole and 9 (5 treated and 4 untreated) were positive for H. pylori infection. The Proteobacteria, Firmicutes, Bacteroidetes, Fusobacteria, and Actinobacteria phyla accounted for 98% of all of the sequences, with Helicobacter, Streptococcus, and Prevotella ranking among the 10 most abundant genera. H. pylori infection or PPI treatment did not significantly influence gastric microbial species composition in dyspeptic patients. Principal-coordinate analysis of weighted UniFrac distances in these communities revealed clear but significant separation according to H. pylori status only. However, in PPI-treated patients, Firmicutes, particularly Streptococcaceae, were significantly increased in relative abundance compared to those in untreated patients. Consistently, Streptococcus was also found to significantly increase in relation to PPI treatment, and this increase seemed to occur independently of H. pylori infection. Our results suggest that Streptococcus may be a key indicator of PPI-induced gastric microbial composition changes in dyspeptic patients. Whether the gastric microbiota alteration contributes to dyspepsia needs further investigation. IMPORTANCE: Although PPIs have become a popular treatment choice, a growing number of dyspeptic patients may be treated unnecessarily. We found that patients treated with omeprazole showed gastric microbial communities that were different from those of untreated patients. These differences regarded the abundances of specific taxa. By understanding the relationships between PPIs and members of the gastric microbiota, it will be possible to envisage new strategies for better managing patients with dyspepsia.


Assuntos
Bactérias/isolamento & purificação , Dispepsia/microbiologia , Mucosa Gástrica/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Infecções por Helicobacter/microbiologia , Inibidores da Bomba de Prótons/uso terapêutico , Adulto , Idoso , Antibacterianos/uso terapêutico , Bactérias/classificação , Bactérias/genética , Bacteroidetes/classificação , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Dispepsia/tratamento farmacológico , Feminino , Firmicutes/classificação , Firmicutes/genética , Firmicutes/isolamento & purificação , Mucosa Gástrica/efeitos dos fármacos , Microbioma Gastrointestinal/genética , Genes de RNAr , Infecções por Helicobacter/tratamento farmacológico , Helicobacter pylori/efeitos dos fármacos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Pessoa de Meia-Idade , Omeprazol/uso terapêutico , Proteobactérias/classificação , Proteobactérias/genética , Proteobactérias/isolamento & purificação , Inibidores da Bomba de Prótons/efeitos adversos , RNA Ribossômico 16S/genética , Streptococcus/classificação , Streptococcus/genética , Streptococcus/isolamento & purificação
9.
Dig Dis ; 34(3): 269-78, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27027301

RESUMO

Antibiotics are mainly used in clinical practice for their activity against pathogens, but they also alter the composition of commensal gut microbial community. Rifaximin is a non-absorbable antibiotic with additional effects on the gut microbiota about which very little is known. It is still not clear to what extent rifaximin can be able to modulate gut microbiota composition and diversity in different clinical settings. Studies based on culture-dependent techniques revealed that rifaximin treatment promotes the growth of beneficial bacteria, such as Bifidobacteria and Lactobacilli. Accordingly, our metagenomic analysis carried out on patients with different gastrointestinal and liver diseases highlighted a significant increase in Lactobacilli after rifaximin treatment, persisting in the short time period. This result was independent of the disease background and was not accompanied by a significant alteration of the overall gut microbial ecology. This suggests that rifaximin can exert important eubiotic effects independently of the original disease, producing a favorable gut microbiota perturbation without changing its overall composition and diversity.


Assuntos
Antibacterianos/farmacologia , Microbioma Gastrointestinal/efeitos dos fármacos , Rifamicinas/farmacologia , Antibacterianos/uso terapêutico , DNA Bacteriano/isolamento & purificação , Humanos , Lactobacillus/efeitos dos fármacos , Rifamicinas/administração & dosagem , Rifaximina
10.
Infect Immun ; 83(1): 364-71, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25385793

RESUMO

We previously showed that the mutant strain of Enterococcus faecalis lacking the transcriptional regulator SlyA is more virulent than the parental strain. We hypothesized that this phenotype was due to overexpression of the second gene of the slyA operon, ef_3001, renamed pmvE (for polyamine metabolism and virulence of E. faecalis). PmvE shares strong homologies with N(1)-spermidine/spermine acetyltransferase enzymes involved in the metabolism of polyamines. In this study, we used an E. faecalis strain carrying the recombinant plasmid pMSP3535-pmvE (V19/p3535-pmvE), which allows the induction of pmvE by addition of nisin. Thereby, we showed that the overexpression of PmvE increased the virulence of E. faecalis in the Galleria mellonella infection model, as well as the persistence within peritoneal macrophages. We were also able to show a direct interaction between the His-tagged recombinant PmvE (rPmvE) protein and putrescine by the surface plasmon resonance (SPR) technique on a Biacore instrument. Moreover, biochemical assays showed that PmvE possesses an N-acetyltransferase activity toward polyamine substrates. Our results suggest that PmvE contributes to the virulence of E. faecalis, likely through its involvement in the polyamine metabolism.


Assuntos
Acetiltransferases/metabolismo , Enterococcus faecalis/crescimento & desenvolvimento , Acetiltransferases/genética , Animais , Expressão Gênica , Lepidópteros , Ligação Proteica , Putrescina/metabolismo , Ressonância de Plasmônio de Superfície , Virulência
11.
BMC Infect Dis ; 14: 634, 2014 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-25480675

RESUMO

BACKGROUND: Mathematical or statistical tools are capable to provide a valid help to improve surveillance systems for healthcare and non-healthcare-associated bacterial infections. The aim of this work is to evaluate the time-varying auto-adaptive (TVA) algorithm-based use of clinical microbiology laboratory database to forecast medically important drug-resistant bacterial infections. METHODS: Using TVA algorithm, six distinct time series were modelled, each one representing the number of episodes per single 'ESKAPE' (E nterococcus faecium, S taphylococcus aureus, K lebsiella pneumoniae, A cinetobacter baumannii, P seudomonas aeruginosa and E nterobacter species) infecting pathogen, that had occurred monthly between 2002 and 2011 calendar years at the Università Cattolica del Sacro Cuore general hospital. RESULTS: Monthly moving averaged numbers of observed and forecasted ESKAPE infectious episodes were found to show a complete overlapping of their respective smoothed time series curves. Overall good forecast accuracy was observed, with percentages ranging from 82.14% for E. faecium infections to 90.36% for S. aureus infections. CONCLUSIONS: Our approach may regularly provide physicians with forecasted bacterial infection rates to alert them about the spread of antibiotic-resistant bacterial species, especially when clinical microbiological results of patients' specimens are delayed.


Assuntos
Algoritmos , Infecções Bacterianas/microbiologia , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/isolamento & purificação , Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Infecções Bacterianas/epidemiologia , Farmacorresistência Bacteriana , Feminino , Previsões/métodos , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Modelos Estatísticos , Vigilância da População , Staphylococcus aureus , Fatores de Tempo
12.
Antimicrob Agents Chemother ; 57(3): 1275-82, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23263007

RESUMO

Aspergillus fumigatus biofilms represent a problematic clinical entity, especially because of their recalcitrance to antifungal drugs, which poses a number of therapeutic implications for invasive aspergillosis, the most difficult-to-treat Aspergillus-related disease. While the antibiofilm activities of amphotericin B (AMB) deoxycholate and its lipid formulations (e.g., liposomal AMB [LAMB]) are well documented, the effectiveness of these drugs in combination with nonantifungal agents is poorly understood. In the present study, in vitro interactions between polyene antifungals (AMB and LAMB) and alginate lyase (AlgL), an enzyme degrading the polysaccharides produced as extracellular polymeric substances (EPSs) within the biofilm matrix, against A. fumigatus biofilms were evaluated by using the checkerboard microdilution and the time-kill assays. Furthermore, atomic force microscopy (AFM) was used to image and quantify the effects of AlgL-antifungal combinations on biofilm-growing hyphal cells. On the basis of fractional inhibitory concentration index values, synergy was found between both AMB formulations and AlgL, and this finding was also confirmed by the time-kill test. Finally, AFM analysis showed that when A. fumigatus biofilms were treated with AlgL or polyene alone, as well as with their combination, both a reduction of hyphal thicknesses and an increase of adhesive forces were observed compared to the findings for untreated controls, probably owing to the different action by the enzyme or the antifungal compounds. Interestingly, marked physical changes were noticed in A. fumigatus biofilms exposed to the AlgL-antifungal combinations compared with the physical characteristics detected after exposure to the antifungals alone, indicating that AlgL may enhance the antibiofilm activity of both AMB and LAMB, perhaps by disrupting the hypha-embedding EPSs and thus facilitating the drugs to reach biofilm cells. Taken together, our results suggest that a combination of AlgL and a polyene antifungal may prove to be a new therapeutic strategy for invasive aspergillosis, while reinforcing the EPS as a valuable antibiofilm drug target.


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Aspergillus fumigatus/efeitos dos fármacos , Proteínas de Bactérias/farmacologia , Biofilmes/efeitos dos fármacos , Ácido Desoxicólico/farmacologia , Hifas/efeitos dos fármacos , Polissacarídeo-Liases/farmacologia , Aspergillus fumigatus/crescimento & desenvolvimento , Aspergillus fumigatus/ultraestrutura , Biofilmes/crescimento & desenvolvimento , Combinação de Medicamentos , Sinergismo Farmacológico , Polissacarídeos Fúngicos/metabolismo , Hifas/crescimento & desenvolvimento , Hifas/ultraestrutura , Testes de Sensibilidade Microbiana , Microscopia de Força Atômica
13.
Clin Dev Immunol ; 2013: 403121, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23878583

RESUMO

Invasive candidiasis (IC) represents the leading fungal infection of humans causing life-threatening disease in immunosuppressed and neutropenic individuals including also the intensive care unit patients. Despite progress in recent years in drugs development for the treatment of IC, morbidity and mortality rates still remain very high. Historically, cell-mediated immunity and innate immunity are considered to be the most important lines of defense against candidiasis. Nevertheless recent evidence demonstrates that antibodies with defined specificities could act with different degrees showing protection against systemic and mucosal candidiasis. Mycograb is a human recombinant monoclonal antibody against heat shock protein 90 (Hsp90) that was revealed to have synergy when combined with fluconazole, caspofungin, and amphotericin B against a broad spectrum of Candida species. Furthermore, recent studies have established an important role for Hsp90 in mediating Candida resistance to echinocandins, giving to this antibody molecule even more attractive biological properties. In response to the failure of marketing authorization by the CHMP (Committee for Medicinal Products for Human Use) a new formulation of Mycograb, named Mycograb C28Y variant, with an amino acid substitution was developed in recent years. First data on Mycograb C28Y variant indicate that this monoclonal antibody lacked efficacy in a murine candidiasis model.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Antifúngicos/uso terapêutico , Candidíase Invasiva/tratamento farmacológico , Anticorpos Monoclonais Humanizados , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Humanos , Proteínas Recombinantes/uso terapêutico
14.
J Infect Dis ; 206(6): 952-60, 2012 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-22782954

RESUMO

Enterococcus faecalis is an established nosocomial pathogen, yet the pathogenesis of enterococcal infections, particularly of urinary tract infections (UTIs), remains to be fully elucidated. Fibronectin-binding proteins have been identified as potent adhesins in pathogenic Gram-positive cocci. Here, we characterized EfbA, which is encoded by the enterococcal orthologue of Streptococcus pneumoniae pavA. Similar to PavA, the anchorless EfbA protein was localized to the enterococcal cell outer surface and bound to immobilized human fibronectin. In addition to abrogated EfbA expression, deletion of the efbA gene eliminated EfbA from the cell surface and drastically reduced the enterococcal cell binding to immobilized fibronectin. The ΔefbA deletion mutant was highly attenuated vs wild-type in a murine ascending UTI model, consistent with an increased tropism for the kidney relative to the bladder. These results provide the first evidence that EfbA of E. faecalis plays a role in UTIs, probably contributing to the pathogenesis in this site.


Assuntos
Proteínas de Bactérias/metabolismo , Enterococcus faecalis/patogenicidade , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções Urinárias/microbiologia , Animais , Aderência Bacteriana , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Enterococcus faecalis/metabolismo , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Fibronectinas/metabolismo , Imunofluorescência , Deleção de Genes , Regulação Bacteriana da Expressão Gênica/fisiologia , Immunoblotting , Proteínas de Membrana/metabolismo , Camundongos , Microscopia Imunoeletrônica , Ligação Proteica , Proteínas Recombinantes , Virulência
15.
Explor Target Antitumor Ther ; 4(4): 716-726, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37711591

RESUMO

Aim: AT-rich interaction domain 1A (ARID1A) encodes a key component of the SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodeling complex that participates in gene expression. ARID1A alterations are quite common among cancer patients, although their role remains debated. The aim of this article was to study ARID1A-mutated cancer patients. Methods: Molecular and clinical data of cancer patients evaluated at Phase 1 Unit of Fondazione Policlinico Universitario A. Gemelli IRCCS were collected. Molecular analyses were performed using FoundationOne® CDx (Foundation Medicine Inc., Cambridge, MA, United States). Cancer patients with at least one molecular alteration in ARID1A gene were identified as ARID1A+. Results: Among the 270 patients undergoing molecular analysis, we found 25 (9%) with at least one pathogenic alteration in ARID1A. The vast majority of these patients were female (84%). The median age at diagnosis was 59; most of the cancers (15, 60%) were gynecological (especially endometrioid endometrial cancers and clear cell ovarian cancers), diagnosed at an early stage. Frameshift alterations in ARID1A were the most common (19/31, 61%) alterations. The median number of mutations in ARID1A+ population was higher compared to ARID1A- population (6 vs. 4), as well as tumor mutational burden (TMB) [20 mutations/megabase (mut/Mb) vs. 1.26 mut/Mb]. Phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha (PIK3CA), phosphatase and tensin homolog (PTEN), catenin beta 1 (CTNNB1), and lysine methyltransferase 2D (MLL2) mutations were enriched in ARID1A+ population. In this cohort, ARID1A did not display any relation with response to platinum chemotherapy. Cancers with double alterations in ARID1A (ARID1A2+) were all gynecological cancers (83% endometrioid endometrial cancers). Conclusions: This analysis provides clinical and molecular details about the phenotypes of ARID1A+ cancers, in particular the subgroup of gynecologic cancers. The high frequency of concurrent mutations in the phosphoinositide 3-kinase (PI3K) pathway among endometrioid endometrial cancers may support the proposal of a new treatment strategy based on the combination of ataxia telangiectasia and Rad3-related (ATR) inhibitor and PIK3CA inhibitor.

16.
Cancers (Basel) ; 15(6)2023 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-36980630

RESUMO

Trophoblast cell surface antigen-2 (Trop-2) is a glycoprotein that was first described as a membrane marker of trophoblast cells and was associated with regenerative abilities. Trop-2 overexpression was also described in several tumour types. Nevertheless, the therapeutic potential of Trop-2 was widely recognized and clinical studies with drug-antibody conjugates have been initiated in various cancer types. Recently, these efforts have been rewarded with the approval of sacituzumab govitecan from both the Food and Drug Administration (FDA) and European Medicines Agency (EMA), for metastatic triple-negative breast cancer patients. In our work, we briefly summarize the various characteristics of cancer cells overexpressing Trop-2, the pre-clinical activities of specific inhibitors, and the role of anti-Trop-2 therapy in current clinical practice. We also review the ongoing clinical trials to provide a snapshot of the future developments of these therapies.

17.
Sci Rep ; 13(1): 14775, 2023 09 07.
Artigo em Inglês | MEDLINE | ID: mdl-37679428

RESUMO

Gut microbiota is an emerging editable cardiovascular risk factor. We aim to investigate gut and coronary plaque microbiota, using fecal samples and angioplasty balloons from patients with acute coronary syndrome (ACS), chronic coronary syndrome (CCS) and control subjects. We examined bacterial communities in gut and coronary plaques by 16S rRNA sequencing and we performed droplet digital PCR analysis to investigate the gut relative abundance of the bacterial genes CutC/CntA involved in trimethylamine N-oxide synthesis. Linear discriminant analysis effect size (LEfSe) at the genus and species levels displayed gut enrichment in Streptococcus, Granulicatella and P. distasonis in ACS compared with CCS and controls; Roseburia, C. aerofaciens and F. prausnitzii were more abundant in controls than in patients. Principal component analysis (PCA) of 41 differentially abundant gut taxa showed a clustering of the three groups. In coronary plaque, LEfSe at the genus level revealed an enrichment of Staphylococcus and Streptococcus in ACS, and Paracoccus in CCS, whereas PCA of 15 differentially abundant plaque taxa exhibited clustering of ACS and CCS patients. CutC and CntA genes were more abundant in ACS and CCS than in controls while no significant difference emerged between ACS and CCS. Our results indicate that ACS and CCS exhibit a different gut and plaque microbial signature, suggesting a possible role of these microbiotas in coronary plaque instability.


Assuntos
Síndrome Coronariana Aguda , Angioplastia com Balão , Carnobacteriaceae , Humanos , RNA Ribossômico 16S/genética , Coração
18.
Cancers (Basel) ; 14(4)2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35205637

RESUMO

(1) Background: Drug development in oncology is changing rapidly. The aim of the present study was to provide an insight into the features of anti-tumor drugs approved in Europe; (2) Methods: We included all the indications for solid tumors issued by the European Medicines Agency (EMA) between 2015 and 2020. We extracted data from European Public Assessments Reports (EPAR), including drug name, mechanism of action, setting, features of pivotal clinical trials, primary end-points, quality of life (QoL); (3) Results: In the explored period, EMA issued 132 new indications (81 indications' extensions) for 62 oncology drugs. In about half of indications (47%), the approval was biomarker-based. Immune check point inhibitors (ICIs) and signal transduction inhibitors were the two most representative drug categories (62%). Most of the indications were for the advanced setting (91%) and front-line therapy (66%). The most common tumor types were non-small cell lung cancer (24%), breast (16%), and melanoma (10%). Two thirds of the indications (73%) were approved based on phase III trials. Overall survival (OS) represented the primary end-point only in 39% of indications, mainly limited to advanced setting (98%) and ICI trials (80%). Almost all (94%) cell cycle and DNA repair mechanism inhibitors were approved based on progression free survival (PFS) data. In pivotal trials with signal transduction inhibitors, objective response rate (ORR) was the prevalent (45%) primary end-point. QoL was never considered as primary end-point; (4) Conclusions: In this analysis, we intended to offer an updated picture of the recent drug development in oncology. Most of the efforts led to broadening indications of pre-existing molecules, with signal transduction inhibitor and ICIs contending the leadership. Twenty-seven percent of the indication were approved without a phase III trial. The majority of drugs entered the market without evidence of OS or QoL benefit but based on surrogate outcomes.

19.
Hepatol Commun ; 6(6): 1492-1501, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35261212

RESUMO

The gut microbiota is a well-known prognostic factor and a modulator of treatment sensitivity in patients with cancers treated with immune checkpoint inhibitors. However, data on hepatocellular carcinoma (HCC) are lacking. This study aimed to evaluate the prognostic role of the gut microbiota and changes produced by immunotherapy on the intestinal environment in patients with cirrhosis and HCC. Eleven patients treated with Tremelimumab and/or Durvalumab were included in the analysis. All study participants underwent gut microbiota profiling, quantification of fecal calprotectin, serum levels of zonulin-1, lipopolysaccharide binding protein (LBP), and programmed death-ligand 1 (PD-L1) at baseline and at each treatment cycle until the third cycle, then every three cycles until treatment discontinuation or last visit. The 6 patients who achieved disease control (DC) showed lower pretreatment fecal calprotectin (median, 12.5; interquartile range [IQR], 5-29 vs. median, 116; IQR, 59-129 µg/g; P = 0.047) and PD-L1 serum levels (median, 0.08; IQR, 0.07-0.09 vs. median, 1.04; IQR, 0.17-1.95 ng/mL; P = 0.02) than nonresponders. The relative abundance of Akkermansia (log2 fold change [FC], 2.72; adjusted P [Padj] = 0.012) was increased, whereas that of Enterobacteriaceae (log2 FC, -2.34; Padj = 0.04) was reduced in the DC group. During treatment, fecal calprotectin showed a temporal evolution opposite to the Akkermansia to Enterobacteriaceae ratio and gut microbiota alpha diversity, but similar to zonulin-1 and LBP. Bifidobacterium had a stable behavior in patients with a long follow-up, while Akkermansia was more variable. Akkermansia and Bifidobacterium showed similar temporal patterns and causative relationships with Prevotella, Veillonella, Ruminococcus, Roseburia, Lachnospira, Faecalibacterium, and Clostridium. Conclusion: A favorable composition of the gut microbiota and low intestinal inflammation are associated with achieving DC. The intestinal environment changes dynamically during therapy.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Akkermansia , Antígeno B7-H1 , Carcinoma Hepatocelular/tratamento farmacológico , Disbiose/microbiologia , Humanos , Inibidores de Checkpoint Imunológico/uso terapêutico , Complexo Antígeno L1 Leucocitário , Neoplasias Hepáticas/tratamento farmacológico
20.
New Microbiol ; 34(3): 281-6, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21811748

RESUMO

The combinatorial phage display library approach to antibody repertoire cloning offers a powerful tool for the isolation of specific antibodies to defined target antigens. Panning strategy is often a very critical point for selecting antibody displayed on the surface of bacteriophages. Most selection strategies described to date have relied on the availability of purified and often recombinant antigen, providing the possibility to perform selections on a well defined antigen source. However, when the antigen is difficult to purify by means of laborious and time-consuming chromatography procedures, panning of phage antibody libraries has to be performed on complex antigen sources such as cell surfaces or tissue sections, or even by in vivo selection methods. This provides a series of technical and experimental complications. In the present work, we successfully generated a mouse monoclonal antibody fragment from a phage display library directed against protein E7 of HPV18 avoiding antigen purification as for immunizing mice as for antibody library selection. Our work demonstrates the feasibility of phage antibody selections on antigens transferred to a nitrocellulose membrane as solid support, using one-dimensional polyacrylamide gel electrophoresis system as the only practice to separate a given antigen present in bacterial crude cell lysate.


Assuntos
Anticorpos Monoclonais/imunologia , Antígenos/química , Colódio/química , Biblioteca de Peptídeos , Animais , Anticorpos Monoclonais/isolamento & purificação , Western Blotting , Eletroforese em Gel de Poliacrilamida , Células HeLa , Papillomavirus Humano 18 , Humanos , Camundongos
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