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1.
New Microbiol ; 47(2): 164-171, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39023526

RESUMO

The study objective is to examine epidemiological and microbiological aspects of aerobic vaginitis in female patients admitted to University Hospital of Campania "L. Vanvitelli" over five years. The most represented strains were E. coli (n = 153), Citrobacter spp. increasing from 2020, E. faecalis (n = 149), S. haemolitycus (n = 61), and Candida albicans (n = 87). The susceptibility patterns of a selection of gram-negative and gram-positive representative bacterial isolates were examined. Carbapenems, aminoglycosides, and fosfomycin were most effective against gram-negative bacteria, whereas vancomycin, daptomycin, and linezolid exhibited greater efficacy against gram-positive bacteria. None of the E. coli and Citrobacter spp. isolates produced extended-spectrum beta-lactamases, and the S. haemolyticus strains were methicillin-resistant. In gram-positive isolates, gentamicin susceptibility increased in 2020 and 2021 compared to clindamycin; erythromycin showed high resistance rates in 2020. Our findings indicate that integrating proper microbiological cultures into clinical practice could improve the management of aerobic vaginitis. Moreover, they highlight the necessity of establishing a nationwide surveillance guideline to mitigate antimicrobial resistance. Improvement actions in antimicrobial diagnostic stewardship must be considered when seeking the appropriate diagnosis and treatment for aerobic vaginitis.


Assuntos
Antibacterianos , Gestão de Antimicrobianos , Testes de Sensibilidade Microbiana , Feminino , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Adulto , Farmacorresistência Bacteriana , Pessoa de Meia-Idade , Vaginose Bacteriana/microbiologia , Vaginose Bacteriana/tratamento farmacológico , Vaginose Bacteriana/diagnóstico , Adulto Jovem , Vaginite/microbiologia , Vaginite/tratamento farmacológico
2.
IDCases ; 36: e01959, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38681078

RESUMO

Magnusiomyces capitatus (M. capitatus) is an emerging opportunistic yeast in the Mediterranean region typically isolated from immunocompromised patients, usually affected by blood malignancies. We reported a rare case of M. capitatus infection, isolated from a drainage fluid in a patient affected by lung cancer recovered in the University Hospital of Campania "Luigi Vanvitelli", Naples, Italy. The isolate was identified by phenotypic methods, i.e., Gram and Lactophenol cotton blue (LCB) staining, and matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) analysis. We identified M. capitatus on the third day from Sabouraud Dextrose Agar supplemented with chloramphenicol and gentamicin. Antifungal susceptibility test revealed that 5-fluorocytosine was the most active drug against M. capitatus, followed by itraconazole and voriconazole, micafungin, amphotericin B and fluconazole, posaconazole, anidulafungin, and caspofungin. Our data showed the importance of an early cultural and fast microbiology diagnosis based on the characteristic morphologic features observed in Gram-stained smears of blood culture positive bottles, and the validation via MALDI-TOF MS. This dual approach has significant impact in the clinical management of infectious diseases and antibiotic stewardship, by integrating sample processing, fluid handling, and detection for rapid bacterial diagnosis.

3.
Sci Data ; 11(1): 220, 2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38374088

RESUMO

Tuberculosis (TB) is one of the deadliest infectious disorders in the world. To effectively TB manage, an essential step is to gain insight into the lineage of Mycobacterium tuberculosis (MTB) and the distribution of drug resistance. Although the Campania region is declared a cluster area for the infection, to contribute to the effort to understand TB evolution and transmission, still poorly known, we have generated a dataset of 159 genomes of MTB strains, from Campania region collected during 2018-2021, obtained from the analysis of whole genome sequence. The results show that the most frequent MTB lineage is the 4 according for 129 strains (81.11%). Regarding drug resistance, 139 strains (87.4%) were classified as multi susceptible, while the remaining 20 (12.58%) showed drug resistance. Among the drug-resistance strains, 8 were isoniazid-resistant MTB, 4 multidrug-resistant MTB, while only one was classified as pre-extensively drug-resistant MTB. This dataset expands the existing available knowledge on drug resistance and evolution of MTB, contributing to further TB-related genomics studies to improve the management of this disease.


Assuntos
Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Antituberculosos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Isoniazida/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia
4.
New Microbiol ; 45(4): 338-343, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36538299

RESUMO

The aim of this study was to describe the prevalence and epidemiology distribution of K. pneumoniae isolated at University Hospital of Campania "Luigi Vanvitelli," including the susceptibility evolution profile. Data on resistant phenotype strains, such as extended-spectrum-ß-lactamase (ESBL) producers and carbapenem-resistant K. pneumoniae (CRE) isolates, were also reported. K. pneumoniae strains were collected at the Complex Operative Unit (UOC) of Virology and Microbiology from different colonization and infection sites from January 2016 to December 2020. The highest rates of isolation were in urinary samples and in respiratory and wound swabs. Antibiotics susceptibility patterns showed more than 50% of the isolates resistant to cephalosporins, fluoroquinolones and penicillin. On the other hand, from 20% to 40% of K. pneumoniae strains were resistant to carbapenems and aminoglycosides. Based on our analysis, fosfomycin, ceftazidime/avibactam and ceftolozane/tazobactam are still therapeutic alternatives. Data analysis on carbapenem class evolution in 2016-2020 showed a significant increase in resistance rates (p<0.05). Increased rates in CRE and ESBL producing K. pneumoniae since 2017 were reported. Providing information on clinical characteristics and epidemiology data on contemporary K. pneumoniae evolution could help mitigate the spread of these isolates in our hospital and avert the endemic levels that have been observed in Southern Italy and in other European countries.


Assuntos
Fosfomicina , Infecções por Klebsiella , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Klebsiella pneumoniae/genética , Farmacorresistência Bacteriana , Carbapenêmicos/farmacologia , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/tratamento farmacológico
5.
New Microbiol ; 45(4)2022 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-36066216

RESUMO

Viral hepatitis still represents a significant worldwide public health issue, being an important cause of morbidity and mortality. The aim of our study is to evaluate the prevalence of Hepatitis B virus (HBV) markers from serologic analysis of hospitalized patients at University Hospital of Campania "Luigi Vanvitelli" and also to investigate the prevalence of HBV/HCV coinfection. We screened serum Anti-Hepatitis B surface antigen (HBsAg), antibody to HBsAg (anti-HBs), antibody to hepatitis B core antigen (anti-HBc), and antibody to Hepatitis C Virus (Anti-HCV) Anti-HCV from January to December 2020. Analyses of HBV serological profile based on age showed that the 51-60 age group was the most numerous and with the highest cases of HBsAg. The 61-70 age group recorded the highest prevalence of anti-HBc while age groups 0-10 years and 31-40 years the highest cases of anti-HBs. Antibody levels decline with time. In subjects older than 20 years, compared to vaccinated cohort individuals, anti-HBc seropositive prevalence increased linearly. This study underlined, in our geographic region, the decreased incidence of hepatitis B and high immunogenicity in the young population. Therefore, administration of HBV vaccine booster dose should be considered for the population rather than vaccination in the first year of life. In conclusion, our findings reaffirm the importance of health surveillance in hospitalized subjects, stressing the need to improve immunized subjects to increase the general population's health.

6.
Int J Microbiol ; 2021: 9033278, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34426740

RESUMO

Microbial biofilms pose a serious threat to patients requiring medical devices (MDs). Prolonged periods of implantation carry a high risk of device-related infections (DRIs). Patients with DRIs often have negative outcomes following the failure of antibiotic treatment. Resistant DRIs are mainly due to the MDs contamination by bacteria producing biofilm. The present study aimed to detect biofilm formation among MD bacterial isolates and to explore their antibiotic resistance profile. The study was conducted on 76 MDs, collected at University Hospital of Campania "Luigi Vanvitelli," between October 2019 and September 2020. Identification of isolates and antibiotic susceptibility testing were performed using Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) and Phoenix Becton Dickinson, respectively. Biofilm-forming abilities were assessed using the tissue culture plate (TCP) method. Among the 94 MDs isolated strains, 42.7% were Gram-positive, 40.3% Gram-negative, and 17% Candida species. Among 78 bacterial strains, 43.6% were non-biofilm producers while 56.4% produced biofilms. All biofilm producing isolates were sensitive to a limited spectrum of antibiotic classes. All moderate and strong biofilm producers and 81% of weak biofilm producers were Multidrug Resistance (MDR) strains. In contrast, among non-biofilm producers, only 11.8% were classified as MDR strains. Our results highlighted that Sulfamides and Glycopeptides for the major Gram-positive strains and Fluoroquinolones, Carbapenems, and Aminoglycosides for the most represented Gram-negative isolates could be the most suitable therapeutic choice for most biofilm-DRIs.

7.
Intervirology ; 62(1): 15-22, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31117080

RESUMO

Epstein-Barr virus (EBV) is a common herpesvirus that may cause asymptomatic infection or various diseases, such as mononucleosis, lymphoproliferative disorders and several cancers. Our objective was to estimate the prevalence of EBV among patients hospitalized in "Luigi Vanvitelli" University Hospital in the last 10 years. Our results showed that EBV seroprevalence in our geographical area was 65%. Seroprevalence increased gradually with age with no significant difference between females (49.42%) and males (50.58%). The seropositivity for primary infection was higher in patients about 5 years old, while seropositivity for past infection was predominant in patients of about 35 years old. These results underline that children in our country are still exposed to EBV. The development and the deeper use of an EBV vaccine in the early years of life could represent the solution for this infection.


Assuntos
Anticorpos Antivirais/sangue , Infecções Assintomáticas/epidemiologia , Infecções por Vírus Epstein-Barr/epidemiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Infecções por Vírus Epstein-Barr/diagnóstico , Feminino , Herpesvirus Humano 4 , Hospitais Universitários , Humanos , Lactente , Recém-Nascido , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Estudos Soroepidemiológicos , Adulto Jovem
8.
Antimicrob Agents Chemother ; 58(9): 5280-90, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24957834

RESUMO

The marine environment has been poorly explored in terms of potential new molecules possessing antibacterial activity. Antimicrobial peptides (AMPs) offer a new potential class of pharmaceuticals; however, further optimization is needed if AMPs are to find broad use as antibiotics. We focused our studies on a peptide derived from the epidermal mucus of hagfish (Myxine glutinosa L.), which was previously characterized and showed high antimicrobial activity against human and fish pathogens. In the present work, the activities of myxinidin peptide analogues were analyzed with the aim of widening the original spectrum of action of myxinidin by suitable changes in the peptide primary structure. The analysis of key residues by alanine scanning allowed for the design of novel peptides with increased activity. We identified the amino acids that are of the utmost importance for the observed antimicrobial activities against a set of pathogens comprising both Gram-negative and Gram-positive bacteria. Overall, optimized bactericidal potency was achieved by adding a tryptophan residue at the N terminus and by the simultaneous substitution of residues present in positions 3, 4, and 11 with arginine. These results indicate that the myxinidin analogues emerge as an attractive alternative for treating drug-resistant infectious diseases and provide key insights into a rational design for novel agents against these pathogens.


Assuntos
Antibacterianos/farmacologia , Proteínas de Peixes/farmacologia , Oligopeptídeos/farmacologia , Antibacterianos/química , Dicroísmo Circular , Escherichia coli/efeitos dos fármacos , Proteínas de Peixes/síntese química , Proteínas de Peixes/química , Klebsiella pneumoniae/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Testes de Sensibilidade Microbiana , Oligopeptídeos/síntese química , Oligopeptídeos/química , Pseudomonas aeruginosa/efeitos dos fármacos , Salmonella typhi/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Relação Estrutura-Atividade
9.
Int J Nanomedicine ; 9: 2137-48, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24855352

RESUMO

The use of micelle aggregates formed from peptide amphiphiles (PAs) as potential synthetic self-adjuvant vaccines to treat Herpes simplex virus (HSV) infection are reported here. The PAs were based on epitopes gB409-505 and gD301-309, selected from HSV envelope glycoprotein B (gB) and glycoprotein D (gD), that had their N-terminus modified with hydrophobic moieties containing two C18 hydrocarbon chains. Pure and mixed micelles of gB and/or gD peptide epitopes were easily prepared after starting with the synthesis of corresponding PAs by solid phase methods. Structural characterization of the aggregates confirmed that they were sufficiently stable and compatible with in vivo use: critical micelle concentration values around 4.0 ⋅ 10(-7) mol ⋅ Kg(-1); hydrodynamic radii (RH) between 50-80 nm, and a zeta potential (ζ) around - 40 mV were found for all aggregates. The in vitro results indicate that both peptide epitopes and micelles, at 10 µM, triggered U937 and RAW 264.7 cells to release appreciable levels of cytokines. In particular, interleukin (IL)-23-, IL-6-, IL-8- or macrophage inflammatory protein (MIP)-2-, and tumor necrosis factor (TNF)-α-release increased considerably when cells were treated with the gB-micelles or gD-micelles compared with the production of the same cytokines when the stimulus was the single gB or gD peptide.


Assuntos
Citocinas/imunologia , Fatores Imunológicos/síntese química , Fatores Imunológicos/farmacologia , Macrófagos/imunologia , Peptídeos/farmacologia , Proteínas do Envelope Viral/química , Animais , Estudos de Viabilidade , Humanos , Macrófagos/efeitos dos fármacos , Camundongos , Micelas , Peptídeos/síntese química , Tensoativos/síntese química , Tensoativos/farmacologia , Células U937
10.
Chemistry ; 18(43): 13678-85, 2012 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-22968943

RESUMO

A poly(amide)-based dendrimer was synthesized and functionalized with the membrane-interacting peptide gH(625-644) (gH625) derived from the herpes simplex virus type 1 (HSV-1) envelope glycoprotein H, which has previously been shown to assist in delivering large cargoes across the cellular membrane. We demonstrate that the attachment of the gH625 peptide sequence to the termini of a dendrimer allows the conjugate to penetrate into the cellular matrix, whereas the unfunctionalized dendrimer is excluded from translocation. The peptide-functionalized dendrimer is rapidly taken into the cells mainly through a non-active translocation mechanism. Our results suggest that the presented peptidodendrimeric scaffold may be a promising material for efficient drug delivery.


Assuntos
Dendrímeros/química , Herpesvirus Humano 1/metabolismo , Proteínas do Envelope Viral/metabolismo , Sequência de Aminoácidos , Membrana Celular/metabolismo , Química Click , Dendrímeros/síntese química , Corantes Fluorescentes/química , Células HeLa , Humanos , Microscopia de Fluorescência , Dados de Sequência Molecular , Proteínas do Envelope Viral/química
11.
Int J Nanomedicine ; 7: 2361-71, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22654515

RESUMO

Haemophilus influenzae type b (Hib) is one of the leading causes of invasive bacterial infection in young children. It is characterized by inflammation that is mainly mediated by cytokines and chemokines. One of the most abundant components of the Hib outer membrane is the P2 porin, which has been shown to induce the release of several inflammatory cytokines. A synthetic peptide corresponding to loop L7 of the porin activates JNK and p38 mitogen-activated protein kinase (MAPK) pathways. We report a novel use of the complementary peptide approach to design a peptide that is able to bind selectively to the protein P2, thereby reducing its activity. This work provides insights into essential molecular details of P2 that may affect the pathogenesis of Hib infections where interruption of the signaling cascade could represent an attractive therapeutic strategy.


Assuntos
Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Domínio Catalítico/efeitos dos fármacos , Peptídeos/química , Peptídeos/metabolismo , Porinas/química , Porinas/metabolismo , Algoritmos , Cromatografia em Gel , Haemophilus influenzae , Humanos , Interleucina-6/metabolismo , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Modelos Biológicos , NF-kappa B/metabolismo , Peptídeos/farmacologia , Ligação Proteica , Salmonella typhimurium , Fator de Transcrição AP-1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Células U937
12.
Mol Biosyst ; 8(12): 3166-77, 2012 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-22710358

RESUMO

Bacterial derived lipoproteins constitute potent macrophage activators in vivo and are effective stimuli, enhancing the immune response especially with respect to low or non-immunogenic compounds. In the present study we have prepared branched lipopeptide constructs in which different (B- and T-cell) epitopes of Herpes simplex virus type 1, derived from glycoproteins B (gB) and D (gD), are linked to a synthetic lipid core. The ability of the lipid core peptide (LCP) constructs (LCP-gB and LCP-gD) to induce cytokine expression and activate the mitogen-activated protein kinase cascade has been evaluated and compared with the behaviour of the isolated epitopes and the lipid core. In this respect, the use of LCP technology coupled with the use of three different gB or gD peptide epitopes in the same branched constructs could represent an interesting approach in order to obtain efficient delivery systems in the development of a synthetic multiepitopic vaccine for the prevention of viral infections.


Assuntos
Imunização , Lipídeos/imunologia , Macrófagos/imunologia , Monócitos/imunologia , Peptídeos/imunologia , Animais , Antígenos de Bactérias/química , Antígenos de Bactérias/imunologia , Proteínas Quinases Dependentes de Cálcio-Calmodulina/antagonistas & inibidores , Linhagem Celular Tumoral , Citocinas/biossíntese , Citocinas/imunologia , Inibidores Enzimáticos/farmacologia , Epitopos de Linfócito B/imunologia , Epitopos de Linfócito T/imunologia , Flavonoides/farmacologia , Herpesvirus Humano 1/imunologia , Humanos , Imidazóis/farmacologia , Metabolismo dos Lipídeos , Ativação de Macrófagos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Proteínas Quinases Ativadas por Mitógeno/imunologia , Peptídeos/metabolismo , Peptídeos/farmacologia , Piridinas/farmacologia , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/metabolismo
13.
Mol Biosyst ; 8(4): 1108-20, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22311336

RESUMO

The failure of conventional vaccines or antimicrobials to combat newly emerging pathogens such as new influenza viruses or antibiotic-resistant bacteria provides significant challenges in the identification of innovative therapeutic approaches and targets for microbial infections. Such therapies, directed towards host-cell molecules, may represent alternative options where conventional approaches face difficulties. We will largely focus on those strategies that directly target the host inflammatory response, specifically those that result in the activation of the nuclear transcription factor (NF)-κB. NF-κB plays a central role in the cellular stress response and in inflammation by controlling the expression of a network of inducers and effectors that define responses to pathogens. Therefore, the modulation of NF-κB activation and its signaling pathway offer an exceptional therapeutical strategy that could benefit from targeting a single host regulatory pathway. The use of NF-κB inhibitors or enhancers will be possible only if modulation between the host's and pathogen's advantage can be reached. Since different pathogens have developed various mechanisms to alter the activation of NF-κB, the present review will mainly focus on the role of NF-κB in microbial infections, highlighting its importance as a therapeutic target and reviewing the current understanding of how NF-κB inhibition can be considered a potential paradigm for the development of novel antimicrobial therapies.


Assuntos
Infecções Bacterianas/tratamento farmacológico , NF-kappa B/antagonistas & inibidores , Viroses/tratamento farmacológico , Animais , Infecções Bacterianas/microbiologia , Humanos , Inflamação/microbiologia , Inflamação/terapia , NF-kappa B/metabolismo , Transdução de Sinais/efeitos dos fármacos , Viroses/virologia
14.
Microbiol Immunol ; 55(5): 347-56, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21288261

RESUMO

During neuropathological conditions such as infections and degenerative diseases, astrocytes can be activated by infiltrating immune cells. Activated astrocytes can produce chemokines, cytokines and adhesion molecules. In this study, the production of IL-6 and adhesion molecules intercellular adhesion molecule-1 (ICAM-1), vascular cellular adhesion molecule-1 (VCAM-1) and E-selectin by human astroglioma cells stimulated with Gram-negative surface components was investigated. Haemophilus influenzae type b porin P2 and its selected active peptide, loop L7, were found to induce MEK1-MEK2/ mitogen-activated protein kinase phosphorylation in U87-MG cells as demonstrated by ELISA, and up-regulate cellular adhesion molecule and interleukin-6 (IL-6) production as shown by RT-PCR and ELISA. Using two potent and selective inhibitors of MEK activation by Raf-1 (PD-098059) and p38 (SB-203580), it was also demonstrated that both ERK1/2 and p38 pathways play key roles in the production of IL-6 as well as in ICAM-1, VCAM-1 and E-selectin expression by Hib porin.


Assuntos
Astrócitos/metabolismo , Proteínas de Bactérias/imunologia , Moléculas de Adesão Celular/metabolismo , Haemophilus influenzae/imunologia , Interleucina-6/metabolismo , Porinas/imunologia , Regulação para Cima , Astrócitos/imunologia , Proteínas de Bactérias/farmacologia , Moléculas de Adesão Celular/genética , Linhagem Celular , Selectina E/genética , Selectina E/metabolismo , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Interleucina-6/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosforilação , Porinas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
15.
Intervirology ; 53(6): 381-9, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20606459

RESUMO

OBJECTIVES: The deciphering of intracellular signaling pathways that are activated by the interaction between viral fusion peptides and cellular membranes are important for the understanding of both viral replication strategies and host defense mechanisms. METHODS: Fusion peptides of several enveloped viruses belonging to different virus families were prepared by standard 9-fluorenylmethoxycarbonyl polyamine solid-phase synthesis and used to stimulate U937 cells in vitro to analyze the phosphorylation patterns of the signaling pathways (PKC, Src, Akt, and MAPK pathways). Immunoprecipitation and Western blotting were carried out by using phosphospecific antibodies. All samples were also assayed for the presence of IL-10 and IFN-beta by ELISA and activation of nuclear factors (AP-1 and NF-kappaB). RESULTS: We have demonstrated that hydrophobic domains of fusion proteins are able to induce several transduction pathways that lead to cytokine (IFN-beta and IL-10) production, an event that appears to be dependent on early activation of AP-1 and NF-kappaB. CONCLUSIONS: The results obtained on the signaling activity of fusion peptides from different viruses enabled us to shed some light on the complex mechanism of viral entry and more precisely we focused on the exact signaling event induced by hydrophobic domains characteristic of fusion peptides interacting with the cell membrane.


Assuntos
Interações Hospedeiro-Patógeno , Interferon beta/biossíntese , Interleucina-10/biossíntese , Transdução de Sinais , Ativação Transcricional , Proteínas Virais de Fusão/imunologia , Western Blotting , Linhagem Celular , Ensaio de Imunoadsorção Enzimática , Humanos , Imunoprecipitação , Monócitos/imunologia , Proteínas Virais de Fusão/síntese química
16.
J Interferon Cytokine Res ; 29(12): 791-800, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19929574

RESUMO

Biological membranes are described as a mosaic of different domains where interactions between membrane components induce the formation of subdomains with different characteristics and functions. Lipids play an important role in the formation of lipid-enriched microdomains where they dynamically associate to form platforms important for membrane protein sorting and construction of signaling complexes. Cholesterol confined in lipid domains is a crucial component required by microorganisms, directly or indirectly, to enter or exit the intracellular compartment. Cellular activation mediated by superficial bacterial component may be modified by local cholesterol depletion. Therefore, new perspectives for unconventional therapeutic intervention in Gram-negative infections may be envisaged. We tested this hypothesis by using methyl-beta-cyclodextrin (mbetaCD) as a cholesterol-complexing agent to alter the U937 plasma membrane cholesterol content. Our results demonstrate that cholesterol depletion of U937 cells inhibited Salmonella enterica serovar Typhimurium porins-mediated phosphorylation of Src kinase family, protein kinase C (PKC), JNK, and p38, while cholesterol repletion restored the phosphorylation. Lipopolysaccharide (LPS) extracted from the same bacterial strain has been used as a control. Our data demonstrate that the lack of activation of signal transduction pathway observed following cholesterol depletion differently modulates the release of interleukin-6 (IL-6) or tumor necrosis factor-alpha (TNF-alpha), suggesting that Src, associated to lipid domains, may represent an important pathway in Gram-negative-induced cellular signal.


Assuntos
Colesterol/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Porinas/metabolismo , Proteína Quinase C/metabolismo , Salmonella typhi/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo , Quinases da Família src/metabolismo , Colesterol/deficiência , Inibidores Enzimáticos/farmacologia , Humanos , Interleucina-6/antagonistas & inibidores , Interleucina-6/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , L-Lactato Desidrogenase/metabolismo , Lipopolissacarídeos/farmacologia , Fosforilação , Proteína Quinase C/antagonistas & inibidores , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/metabolismo , Células U937 , beta-Ciclodextrinas/farmacologia , Proteínas Quinases p38 Ativadas por Mitógeno/antagonistas & inibidores , Quinases da Família src/antagonistas & inibidores
17.
Eur Cytokine Netw ; 20(3): 140-7, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19825524

RESUMO

Interleukin-6 (IL-6) is a pleiotropic cytokine and plays an active role in inflammatory and immune responses, contributing to a multitude of physiological and pathophysiological processes. In this study, we address the molecular mechanism of IL-6 transcriptional induction and propose a correlation between activated NF-kappaB localization and IL-6 expression. In particular, we detected, by ChIP assay, that occupation of the IL-6 gene promoter site is dependent on activated NF-kappaB. In fact, after porin stimulation, the NF-kappaB p65 subunit is activated, translocates to the nucleus and binds to the IL-6 promoter sequence.Elucidation of the host signaling pathways and identification of the transcription factors that contribute to IL-6 expression, may aid in the understanding of host susceptibility to gram-negative infections and in identifying new therapeutic strategies in a variety of infectious diseases.


Assuntos
Núcleo Celular/genética , Interleucina-6/genética , Porinas/farmacologia , Regiões Promotoras Genéticas , Salmonella typhimurium/química , Sequência Consenso/genética , Densitometria , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Interleucina-6/metabolismo , NF-kappa B/metabolismo , Ligação Proteica/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células U937
18.
Cytokine ; 41(3): 279-85, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18206384

RESUMO

The expression of inducible nitric oxide synthase (iNOS) is a critical factor in both physiological and pathological functions. The present study examined the role of mitogen-activated protein kinases (MAPKs) in the regulation of iNOS and proinflammatory cytokine production in RAW 264.7 cells in response to Salmonella enterica serovar Typhimurium porins. By use of Western blotting for iNOS detection and enzyme-linked immunosorbent assay (ELISA) for quantization of cytokine secretion, selective pharmacological inhibitors of MAPK pathways were tested for dissecting the molecular mechanisms underlying the mediation of these signaling in porins-stimulated murine macrophages. S. enterica serovar Typhimurium porins activated iNOS expression, NO production and interleukin (IL)-6, IL-8 and tumor necrosis factor-alpha (TNF-alpha) release. Treatment of cells with SB203580 and SP600125 (inhibitors of p38 and JNK, respectively) significantly affected porin-stimulated iNOS and NO production. Concomitant decrease in the proinflammatory cytokine secretion was detected. These data confirm the importance of the MAPKs cascade in macrophage activation by bacterial product opening up new strategies for therapy of septic shock.


Assuntos
Citocinas/metabolismo , Macrófagos/enzimologia , Proteínas Quinases Ativadas por Mitógeno/fisiologia , Óxido Nítrico Sintase Tipo II/metabolismo , Porinas/metabolismo , Salmonella typhimurium , Animais , Antracenos/farmacologia , Imidazóis/farmacologia , Ativação de Macrófagos , Macrófagos/efeitos dos fármacos , Camundongos , Proteínas Quinases Ativadas por Mitógeno/antagonistas & inibidores , Óxido Nítrico/metabolismo , Porinas/farmacologia , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia
19.
Immunobiology ; 209(10): 729-35, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15969449

RESUMO

The aim of this study was to evaluate a possible relationship between lymphomonocyte expression of heat shock proteins (HSP) 60/27 and plasma levels of pro-inflammatory cytokines (tumor necrosis factor-alpha and interleukin-6) and markers of antioxidant/oxidative status [glutathione (GSH), alpha glutathione-S-transferase activity (alpha GST), malonyldialdeyde (MDA), 4-hydroxinonenal (4-HNE), and S-nitrosothiols (S-NO)] in patients with chronic liver diseases. Entered into the study were 47 subjects: 10 healthy controls, 16 patients with HCV-related chronic hepatitis (CH), and 16 patients with HCV-related and 5 with alcohol-related liver cirrhosis (10 Child A and 11 Child B+C). HSP60 was clearly expressed only in 5% of patients and lowly in the control group. HSP27 was clearly expressed in 46.7% of CH and 71.4% of cirrhotic patients but was lowly present in healthy subjects. A significant difference was found between patients with a low expression of HSP27 (negative patients) and those with a high HSP27 expression (positive patients) of plasma levels both of antioxidants (GSH, p < 0.05), and of markers of enhanced production of free radicals and cytokines (alpha GST, TNF-alpha and IL-6, p < 0.05; MDA, 4-HNE and S-NO, p < 0.01) as well as for alcohol use and degree of liver impairment. The present data are the first showing that, particularly in conditions of enhanced oxidative stress, lymphomonocytes from liver disease patients present an increased expression of HSP27.


Assuntos
Regulação da Expressão Gênica , Proteínas de Choque Térmico/metabolismo , Hepatopatias/metabolismo , Proteínas de Neoplasias/metabolismo , Adulto , Idoso , Consumo de Bebidas Alcoólicas , Antioxidantes/metabolismo , Biomarcadores/sangue , Western Blotting , Doença Crônica , Feminino , Proteínas de Choque Térmico HSP27 , Humanos , Masculino , Pessoa de Meia-Idade , Chaperonas Moleculares , Oxirredução
20.
New Microbiol ; 28(1): 89-92, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15782631

RESUMO

The diagnosis of cutaneous Mycobacterium marinum infection is frequently presumptive, as detection by conventional methods is difficult. We describe a patient with granulomatous skin lesions on the right dorsal hand and forearm. Histological examinations were presumptive for mycobacterium lesions. We identified Mycobacterium marinum directly in the patient's lesional skin biopsy combining polymerase chain reaction (PCR) amplification using Mycobacterium genus-specific primers, and subsequent restriction enzyme analysis enabling identification to the species level. The symptoms were no longer present after specific therapy, thereby confirming the initial diagnosis.


Assuntos
Infecções por Mycobacterium não Tuberculosas/microbiologia , Mycobacterium marinum/isolamento & purificação , Dermatopatias Bacterianas/diagnóstico , Adulto , Enzimas de Restrição do DNA , DNA Bacteriano/análise , Humanos , Itália , Masculino , Mycobacterium , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Mycobacterium marinum/classificação , Reação em Cadeia da Polimerase , Dermatopatias Bacterianas/tratamento farmacológico , Dermatopatias Bacterianas/microbiologia
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