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1.
Front Oncol ; 13: 1221096, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37664032

RESUMEN

Introduction: Primary debulking surgery (PDS), interval debulking surgery (IDS), and platinum-based chemotherapy are the current standard treatments for advanced ovarian cancer (OC). The time to initiation of adjuvant chemotherapy (TTC) could influence patient outcomes. Methods: We conducted a multicenter retrospective cohort study of advanced (International Federation of Gynecology and Obstetrics (FIGO) stage III or IV) OC treated between 2014 and 2018 to assess progression-free survival (PFS) and overall survival (OS) in relation to TTC. All patients underwent a germline multigene panel for BRCA1/2 evaluation. Results: Among the 83 patients who underwent PDS, a TTC ≥ 60 days was associated with a shorter PFS (hazard ratio (HR) 2.02, 95% confidence interval (CI) 1.04-3.93, p = 0.038), although this association lost statistical significance when adjusting for residual disease (HR 1.52, 95% CI 0.75-3.06, p = 0.244, for TTC and HR 2.73, 95% CI 1.50-4.96, p = 0.001, for residual disease). Among 52 IDS patients, we found no evidence of an association between TTC and clinical outcomes. Ascites, type of chemotherapy, or germline BRCA1/2 mutational status did not influence TTC and were not associated with clinical outcomes in PDS or IDS patients. Discussion: In conclusion, longer TTC seems to negatively affect prognosis in patients undergoing PDS, especially those with residual disease.

2.
Int J Mol Sci ; 24(15)2023 Aug 04.
Artículo en Inglés | MEDLINE | ID: mdl-37569793

RESUMEN

Subjects with pathogenic (PV) and likely pathogenic (LPV) FLCN variants have an increased risk of manifesting benign and malignant disorders that are related to Birt-Hogg-Dubé syndrome (BHDS): an autosomal dominantly inherited disorder whose severity can vary significantly. Renal cell carcinoma (RCC) development in BHD (Birt-Hogg-Dubé) patients has a very high incidence; thus, identifying this rare syndrome at early stages and preventing metastatic spread is crucial. Over the last decade, the advancement of Next Generation Sequencing (NGS) and the implementation of multigene panels for hereditary cancer syndromes (HCS) have led to a subsequent focus on additional genes and variants, including those of uncertain significance (VUS). Here, we describe a novel FLCN variant observed in a subject manifesting disorders that were suspected to be related to BHDS and with a family history of multiple cancers.


Asunto(s)
Síndrome de Birt-Hogg-Dubé , Carcinoma de Células Renales , Neoplasias Renales , Síndromes Neoplásicos Hereditarios , Humanos , Síndrome de Birt-Hogg-Dubé/genética , Síndrome de Birt-Hogg-Dubé/patología , Carcinoma de Células Renales/genética , Neoplasias Renales/genética , Neoplasias Renales/patología , Proteínas Proto-Oncogénicas/genética , Proteínas Supresoras de Tumor/genética
3.
Cancers (Basel) ; 15(7)2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37046793

RESUMEN

PVs and LPVs in BRCA1/2 genes are correlated to a high risk of developing breast cancer and/or ovarian cancer (Hereditary Breast and Ovarian Cancer syndrome, HBOC); additionally, in recent years, an increasing number of BRCA 1/2 variants have been identified and associated with pancreatic cancer. Epidemiologic studies have highlighted that inherited factors are involved in 10% to 20% of PCs, mainly through deleterious variants of BRCA2. The frequency of BRCA1/2 germline alterations fluctuates quite a lot among different ethnic groups, and the estimated rate of PVs/LPVs variants in Italian HBOC families is not very accurate, according to different reports. The aim of our study is to describe the prevalence of a BRCA2 PV observed in a selected cohort of HBOC patients and their relatives, whose common origin is the eastern coast of Emilia Romagna, a region of Italy. This study provides insight into the frequency of the variant detected in this area and provides evidence of an increased risk of pancreatic and breast cancer, useful for genetic counseling and surveillance programs.

4.
Int J Mol Sci ; 23(24)2022 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-36555431

RESUMEN

BRCA1 and BRCA2 are the most frequently mutated genes in ovarian cancer (OC) crucial both for the identification of cancer predisposition and therapeutic choices. However, germline variants in other genes could be involved in OC susceptibility. We characterized OC patients to detect mutations in genes other than BRCA1/2 that could be associated with a high risk of developing OC and permit patients to enter the most appropriate treatment and surveillance program. Next-generation sequencing analysis with a 94-gene panel was performed on germline DNA of 219 OC patients. We identified 34 pathogenic/likely pathogenic variants in BRCA1/2 and 38 in other 21 genes. The patients with pathogenic/likely pathogenic variants in the non-BRCA1/2 genes mainly developed OC alone compared to the other groups that also developed breast cancer or other tumors (p = 0.001). Clinical correlation analysis showed that the low-risk patients were significantly associated with platinum sensitivity (p < 0.001). Regarding PARP inhibitors (PARPi) response, the patients with pathogenic mutations in the non-BRCA1/2 genes had worse PFS and OS. Moreover, a statistically significantly worse PFS was found for every increase of one thousand platelets before PARPi treatment. To conclude, knowledge about molecular alterations in genes beyond BRCA1/2 in OC could allow for more personalized diagnostic, predictive, prognostic, and therapeutic strategies for OC patients.


Asunto(s)
Neoplasias de la Mama , Neoplasias Ováricas , Humanos , Femenino , Predisposición Genética a la Enfermedad , Proteína BRCA1/genética , Mutación , Neoplasias Ováricas/tratamiento farmacológico , Genes BRCA2 , Mutación de Línea Germinal , Neoplasias de la Mama/genética , Secuenciación de Nucleótidos de Alto Rendimiento
5.
Front Oncol ; 12: 835346, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35237525

RESUMEN

Birt-Hogg-Dubé syndrome (BHDS) is a rare autosomal dominant inherited disorder caused by a mutation in folliculin (FLCN) gene transmitted via germline autosomal dominant pattern. Patients with this syndrome have an increased susceptibility to renal cell carcinoma, lung cysts, spontaneous pneumothorax, and benign skin hamartomas, and its diagnosis is not easy and consequently underestimated. Several mutations have been identified in FLCN gene, among which the majority of alterations are frameshift (insertion/deletion), nonsense, or splice-site mutations that generally produce unfunctional truncated FLCN proteins. Our aim is to present a case of a BHDS family whose proband is a 56-year-old patient who has been experiencing multiple disorders, has an FLCN genetic mutation, and has also been identified to have a pathogenic variant in BRCA2 gene. Our further purpose is to emphasize the importance of the next-generation sequencing (NGS) approach to identify potential multiple germline mutations in complex and rare oncologic disorders, allowing strict and more targeted cancer screening programs.

6.
BMC Cancer ; 21(1): 611, 2021 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-34034685

RESUMEN

BACKGROUND: Pancreatic cancer (PC) is a major cause of cancer death. In an effort to improve treatment strategies and outcomes, DNA damage repair (DDR) pathways have been introduced as a new target in PC and in other cancers, through the exploitation of synthetic lethality. Furthermore, genes involved in DDR are among the major determinants of cancer susceptibility. In addition to the well-known BRCA1 and BRCA2 genes, a plethora of other targets in the same pathways are now emerging. METHODS: We analyzed samples from 60 patients, affected by PC and already tested for BRCA, using a panel with 24 other cancer susceptibility genes. RESULTS: We detected 8 pathogenic or likely pathogenic mutations (13.3% of samples analyzed), 4 of which were found in non-BRCA genes (2 in ATM, 1 each in PALB2 and RAD50). Furthermore, 4 pathogenic or likely pathogenic mutations were found in patients without a personal or familial history of cancer. CONCLUSIONS: Our results suggest that genetic testing with a comprehensive gene panel should be perfomed in all patients with PC, in order to allow screening for PC and other gene-related cancers in all at risk family members and to assess patients' eligibility for emerging therapeutic options.


Asunto(s)
Biomarcadores de Tumor/genética , Reparación del ADN , Detección Precoz del Cáncer/métodos , Pruebas Genéticas/métodos , Neoplasias Pancreáticas/diagnóstico , Ácido Anhídrido Hidrolasas/genética , Adulto , Anciano , Anciano de 80 o más Años , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteína BRCA1/genética , Proteína BRCA2/genética , Daño del ADN , Análisis Mutacional de ADN/estadística & datos numéricos , Proteínas de Unión al ADN/genética , Detección Precoz del Cáncer/estadística & datos numéricos , Proteína del Grupo de Complementación N de la Anemia de Fanconi/genética , Femenino , Pruebas Genéticas/estadística & datos numéricos , Humanos , Masculino , Anamnesis , Persona de Mediana Edad , Neoplasias Pancreáticas/genética
7.
Diagnostics (Basel) ; 10(5)2020 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-32365798

RESUMEN

Male breast cancer (MBC) is a rare tumor, accounting for less than 1% of all breast cancers. In MBC, genetic predisposition plays an important role; however, only a few studies have investigated in depth the role of genes other than BRCA1 and BRCA2. We performed a Next-Generation Sequencing (NGS) analysis with a panel of 94 cancer predisposition genes on germline DNA from an Italian case series of 70 patients with MBC. Moreover, we searched for large deletions/duplications of BRCA1/2 genes through the Multiplex Ligation-dependent Probe Amplification (MLPA) technique. Through the combination of NGS and MLPA, we identified three pathogenic variants in the BRCA1 gene and six in the BRCA2 gene. Besides these alterations, we found six additional pathogenic/likely-pathogenic variants in PALB2, CHEK2, ATM, RAD51C, BAP1 and EGFR genes. From our study, BRCA1 and BRCA2 emerge as the main genes associated with MBC risk, but also other genes seem to be associated with the disease. Indeed, some of these genes have already been implicated in female breast cancer predisposition, but others are known to be involved in other types of cancer. Consequently, our results suggest that novel genes could be involved in MBC susceptibility, shedding new light on their role in cancer development.

8.
Int J Colorectal Dis ; 34(11): 1999-2002, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31655866

RESUMEN

BACKGROUND: Lynch syndrome (LS) is associated with germline mutations in one of the mismatch repair genes or EPCAM. The majority of the causative alterations are point mutations. Large genomic rearrangements represent only 5-20%. Hypothetically, the allelic imbalance, like the loss of heterozygosity, may be another high penetrance risk factor. CASE PRESENTATION: We describe the case of a patient who developed 5 tumors during her lifetime and with a family history characterized by a high frequency of tumors associated with LS. The proband was tested for mutations and copy number alterations with a panel of hereditary cancer genes and by SNP array. She showed a 187 Kb duplication including EPCAM and the first 7 exons of MSH2, plus two loss of heterozygosity (LOHs) in chromosome 20 and one in chromosome X which include many tumor suppressor genes. CONCLUSION: We found a novel large EPCAM-MSH2 duplication associated with LS and the presence of LOHs in regions containing numerous tumor suppressors, raising the hypothesis that these alterations could contribute to cancer susceptibility. Our results underline the importance to deepen the knowledge of molecular mechanisms in order to determine the role in cancer predisposition of novel genetic alterations.


Asunto(s)
Cromosomas Humanos Par 20/genética , Cromosomas Humanos X/genética , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Molécula de Adhesión Celular Epitelial/genética , Duplicación de Gen , Pérdida de Heterocigocidad/genética , Proteína 2 Homóloga a MutS/genética , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Linaje
9.
Cancers (Basel) ; 11(9)2019 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-31514334

RESUMEN

The main gene involved in gastric cancer (GC) predisposition is CDH1, the pathogenic variants of which are associated with diffuse-type gastric cancer (DGC) and lobular breast cancer (LBC). CDH1 only explains a fraction (10-50%) of patients suspected of DGC/LBC genetic predisposition. To identify novel susceptibility genes, thus improving the management of families at risk, we performed a multigene panel testing on selected patients. We searched for germline pathogenic variants in 94 cancer-related genes in 96 GC or LBC Italian patients with early-onset and/or family history of GC. We found CDH1 pathogenic variants in 10.4% of patients. In 11.5% of cases, we identified loss-of-function variants in BRCA1, BRCA2, PALB2, and ATM breast/ovarian cancer susceptibility genes, as well as in MSH2, PMS2, BMPR1A, PRF1, and BLM genes. In 78.1% of patients, we did not find any variants with clear-cut clinical significance; however, 37.3% of these cases harbored rare missense variants predicted to be damaging by bioinformatics tools. Multigene panel testing decreased the number of patients that would have otherwise remained genetically unexplained. Besides CDH1, our results demonstrated that GC pathogenic variants are distributed across a number of susceptibility genes and reinforced the emerging link between gastric and breast cancer predisposition.

10.
Materials (Basel) ; 11(4)2018 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-29614037

RESUMEN

Complete eradication of bacterial infections is often a challenging task, especially in presence of prosthetic devices. Invasion of non-phagocytic host cells appears to be a critical mechanism of microbial persistence in host tissues. Hidden within host cells, bacteria elude host defences and antibiotic treatments that are intracellularly inactive. The intracellular invasiveness of bacteria is generally measured by conventional gentamicin protection assays. The efficiency of invasion, however, markedly differs across bacterial species and adjustments to the titre of the microbial inocula used in the assays are often needed to enumerate intracellular bacteria. Such changes affect the standardisation of the method and hamper a direct comparison of bacteria on a same scale. This study aims at investigating the precise relation between inoculum, in terms of multiplicity of infection (MOI), and internalised bacteria. The investigation included nine Staphylococcus aureus, seven Staphylococcus epidermidis, five Staphylococcus lugdunensis and two Enterococcus faecalis clinical strains, which are co-cultured with MG63 human osteoblasts. Unprecedented insights are offered on the relations existing between MOI, number of internalised bacteria and per cent of internalised bacteria. New parameters are identified that are of potential use for qualifying the efficiency of internalization and compare the behaviour of bacterial strains.

11.
Oncotarget ; 8(29): 47064-47075, 2017 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-28423363

RESUMEN

As new genes predisposing to breast (BC) and ovarian cancer (OC) are constantly emerging, the use of panels of genes analyzed by Next-Generation Sequencing (NGS) is increasing in clinical diagnostics. The identification of a large number of new germline mutations allows for deeper knowledge of cancer predisposition, although raising many questions about patient management.BC and OC patients recruited by our counseling service between 2012-2015 were included in this study. DNA was extracted from peripheral blood and a panel of 94 genes involved in hereditary tumors was analyzed by NGS. Patient clinical features of BC and OC and cancer family history were collected and compared to the patient genetic profile.A total of 255 women were analyzed, 57 of whom had a pathogenic mutation in BRCA1/2 genes, and 17 carried pathogenic mutations in other genes, such as PALB2, ATM, BRIP1, RAD51D, MSH6, PPM1D, RECQL4, ERCC3, TSC2, SLX4 and other Fanconi anemia genes.Patients with a pathogenic mutation in genes other than BRCA1 and BRCA2 showed no significant difference from the BRCA1/2-mutated carriers with respect to age at diagnosis and clinical features, suggesting that mutations in other genes could pose a high risk of cancer development.These patients had a much higher percentage of bilateral breast cancer (BBC) and a lower rate of OC than BRCA-mutated patients and patients with no pathogenic mutations: as a consequence, the surveillance protocol should be customized to the patient genetic characteristics.


Asunto(s)
Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Síndrome de Cáncer de Mama y Ovario Hereditario/genética , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor , Femenino , Genes BRCA1 , Genes BRCA2 , Pruebas Genéticas , Mutación de Línea Germinal , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Persona de Mediana Edad , Mutación , Linaje
12.
Int J Biol Markers ; 31(4): e461-e465, 2016 Dec 23.
Artículo en Inglés | MEDLINE | ID: mdl-27516001

RESUMEN

Li-Fraumeni syndrome (LFS) is an autosomal dominant disorder occurring at a young age that predisposes individuals to multiple forms of cancer and to a heterogeneous spectrum of malignancies. We describe the clinical history of a patient who had 5 primary malignant cancers and a familiar history consistent with LFS. We analyzed the genomic DNA of the proband and her relatives by next-generation sequencing (NGS) technology using an enrichment protocol for the simultaneous sequencing of 94 genes involved in hereditary cancers. Genetic analysis of the proband revealed a TP53 germline mutation in exon 5 determining a nucleotide alteration at codon 175 (R175H), a hot spot mutation site related to LFS and a reported pathogenic mutation. The proband daughter's and brother's DNA did not carry the TP53 mutation but they had some rare variants in common with the proband, in addition to other variants with a still unclear role. In conclusion, we identified a TP53 mutation in a patient with multiple primary tumors and a family history characterized by a severe susceptibility to cancer. The genetic analysis by targeted NGS led to the identification of the genetic background and to the exclusion of a cancer risk for the family members. Targeted NGS represents an efficient approach for the identification of mutations in families with a heterogeneous phenotype.


Asunto(s)
Mutación de Línea Germinal , Síndrome de Li-Fraumeni/genética , Proteína p53 Supresora de Tumor/genética , Adulto , Femenino , Genes p53/genética , Predisposición Genética a la Enfermedad , Humanos , Síndrome de Li-Fraumeni/patología
13.
J Biomed Mater Res A ; 104(3): 788-801, 2016 03.
Artículo en Inglés | MEDLINE | ID: mdl-26378773

RESUMEN

Septic failure is still the major complication of prosthetic implants. Entering host cells, bacteria hide from host immune defenses, shelter from extracellular antibiotics, and cause chronic infection. Staphylococcus aureus, the leading etiologic agent of orthopedic implant infections, is able to enter bone cells and induce osteoblast apoptosis, osteoclast recruitment, and highly destructive osteomyelitis. Staphylococcus epidermidis, Staphylococcus lugdunensis, and Enterococcus faecalis are opportunistic pathogens causative of implant-related infections. This study investigated the ability to internalize into osteoblastic MG63 cells of 22 S. epidermidis, 9 S. lugdunensis, and 21 E. faecalis clinical isolates from orthopedic implant infections. Isolates were categorized in clusters by ribotyping. Internalization assay was carried out by means of a microtiter plate-based method. S. epidermidis, S. lugdunensis, and E. faecalis strains turned out incompetent to enter osteoblasts, exhibiting negligible internalization into MG63 cells, nearly three orders of magnitude lower than that of S. aureus. Osteoblast invasion does not appear as a pathogenetic mechanism utilized by S. epidermidis, S. lugdunensis, or E. faecalis for infecting orthopedic implants. Moreover, it can be inferred that intracellularly active antimicrobials should not be necessary against implant infections caused by the three bacterial species. Finally, implications with the uptake of biomaterial microparticles by nonphagocytic cells are enlightened. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 788-801, 2016.


Asunto(s)
Enterococcus faecalis/fisiología , Osteoblastos/microbiología , Prótesis e Implantes/microbiología , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Relacionadas con Prótesis/patología , Staphylococcus epidermidis/fisiología , Staphylococcus lugdunensis/fisiología , Aminoglicósidos/farmacología , Línea Celular Tumoral , Recuento de Colonia Microbiana , Enterococcus faecalis/crecimiento & desarrollo , Enterococcus faecalis/aislamiento & purificación , Humanos , Osteoblastos/efectos de los fármacos , Ribotipificación , Staphylococcus epidermidis/crecimiento & desarrollo , Staphylococcus epidermidis/aislamiento & purificación , Staphylococcus lugdunensis/crecimiento & desarrollo , Staphylococcus lugdunensis/aislamiento & purificación
14.
J Biomed Mater Res A ; 103(4): 1447-58, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25046271

RESUMEN

Anti-infective properties of biomedical materials are often achieved by loading or coating them with powerful bactericides. Undesirably, these bioactive molecules can damage the host cells at the biomaterial-tissues interface and, sometimes, even determine systemic toxic effects. The search for biomaterials able to actively resist infection while displaying a safe cytocompatibility profile toward eukaryotic cells is being progressively developed. Poly-(D,L)lactic acid (PLA) is a broadly used resorbable material with established biocompatibility properties. The dissolving surfaces of a biodegradable material tend to be per se elusive for bacteria. Here, films of pristine PLA, of PLA blended with vitamin E (VitE) and PLA blended with vitamin E acetate (VitE ac) were challenged in vitro with the biofilm-producers Staphylococcus epidermidis RP62A and Staphylococcus aureus ATCC25923. The bacterial adhesion properties of the different materials were investigated on small film disc specimens by a method based on microtiter plates. Adherent bacteria were quantified by both CFU plating and bioluminescence. Significant decrease in bacterial adhesion and biofilm accumulation was found on the surface of both the enriched polymers. These findings, together with the favorable intrinsic properties of PLA and the desirable bioactivities conferred by VitE, point up the VitE-blended PLA polymers as gentle anti-infective biomaterials.


Asunto(s)
Antiinfecciosos/farmacología , Adhesión Bacteriana/efectos de los fármacos , Materiales Biocompatibles/farmacología , Ácido Láctico/farmacología , Polímeros/farmacología , Vitamina E/farmacología , Mediciones Luminiscentes , Poliésteres , Staphylococcus aureus/efectos de los fármacos , Staphylococcus epidermidis/efectos de los fármacos , Vitamina E/química
15.
Int J Artif Organs ; 35(10): 800-16, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23065889

RESUMEN

Biomaterial-associated infections have an enormous impact in terms of morbidity of the patients and costs to national health systems. Perioperative antibiotics and aseptic procedures have not proved sufficient to eradicate the occurrence of this type of infections which often lead to devastating effects. Adjunctive strategies for preventing the establishment of infections are increasingly being centered on the development of new biomaterials with anti-infective properties. The creation of new anti-infective biomaterials can be obtained by alternative approaches oriented to achieve either bacteria-repellent surfaces or bioactive surfaces expressing self-sterilizing properties when not even able to treat pre-existing infections in the surrounding tissues. Here, we offer a short overview of the currently available in vitro methods that can be used to investigate and assess the performance of anti-infective biomaterials, with special emphasis on those whose mechanism of action is based on bacteria-repellent surfaces.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Materiales Biocompatibles , Ensayo de Materiales/métodos , Prótesis e Implantes , Infecciones Relacionadas con Prótesis/prevención & control , Animales , Bacterias/crecimiento & desarrollo , Adhesión Bacteriana/efectos de los fármacos , Técnicas Bacteriológicas , Materiales Biocompatibles/efectos adversos , Biopelículas/efectos de los fármacos , Biopelículas/crecimiento & desarrollo , Humanos , Prótesis e Implantes/efectos adversos , Prótesis e Implantes/microbiología , Diseño de Prótesis , Infecciones Relacionadas con Prótesis/microbiología , Propiedades de Superficie
16.
Int J Artif Organs ; 34(9): 832-9, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22094563

RESUMEN

Implant-related infections are difficult to treat because they are very often associated with biofilm-forming micro-organisms capable of resisting host immune defenses and surviving conventional antibiotic treatments. In Staphylococcus epidermidis biofilm-forming strains, the polysaccharide intercellular adhesin (PIA), whose expression is encoded by the icaADBC operon, is recognized as a main staphylococcal accumulation mechanism. Nevertheless, various observations have shown that PIA expression is dispensable and a variety of additional/alternative accumulation mechanisms, including extracellular DNA (eDNA) and several other factors of proteic nature, can compensate for icaADBC low expression or even for its absence. A suggestive hypothesis points to the possibility that changes in biofilm extracellular matrix composition can be induced in different environmental niches. In this study we aimed at investigating the relationship between the exopolysaccharide and eDNA biofilm components, screening 55 S. epidermidis clinical isolates by means of a simple fluorescence-based microtiter-plate assay. Our findings indicate the existence of a certain degree of correlation, although not a strict one, between eDNA and the exopolysaccharide component. The presence of exopolysaccharide greatly varied even in strains belonging to the same strain type determined by automated riboprinting.


Asunto(s)
Biopelículas/crecimiento & desarrollo , ADN Bacteriano/metabolismo , Polisacáridos Bacterianos/metabolismo , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/metabolismo , Desoxirribonucleasa I/metabolismo , Humanos , Italia , Microscopía Fluorescente , Ribotipificación , Staphylococcus epidermidis/clasificación , Staphylococcus epidermidis/genética , Staphylococcus epidermidis/crecimiento & desarrollo , Staphylococcus epidermidis/aislamiento & purificación
17.
Int J Artif Organs ; 34(9): 840-6, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22094564

RESUMEN

Biofilm formation is broadly recognized as an important virulence factor in many bacterial species implicated in implant-related opportunistic infections. In spite of a long history of research and many investigative efforts aimed at elucidating their chemical composition, structure, and function, the nature of bacterial biofilms still remains only partly revealed. Over the years, different extracellular polymeric substances (EPS) have been described that contribute functionally and structurally to the organization of biofilms. Recently extracellular DNA (eDNA) has emerged as a quantitatively conspicuous and potentially relevant structural component of microbial biofilms of many microbial species, Staphylococcus aureus and S. epidermidis among them. The present study aims at comparatively investigating the amount of eDNA present in the biofilm of 55 clinical isolates of S. epidermidis from postsurgical and biomaterial-related orthopedic infections. Quantification of eDNA was performed by a non-destructive method directly on bacterial biofilms formed under static conditions on the plastic surface of 96-well plates.


Asunto(s)
Biopelículas/crecimiento & desarrollo , ADN Bacteriano/metabolismo , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/metabolismo , Desoxirribonucleasa I/metabolismo , Fluorometría , Humanos , Italia , Polisacáridos Bacterianos/metabolismo , Ribotipificación , Staphylococcus epidermidis/clasificación , Staphylococcus epidermidis/genética , Staphylococcus epidermidis/crecimiento & desarrollo , Staphylococcus epidermidis/aislamiento & purificación
18.
Future Microbiol ; 6(11): 1329-49, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22082292

RESUMEN

Infection is still the major complication of orthopedic implants and projections based on the actual trend indicate that total hip and knee arthroplasties and their consequent infection burden are destined to greatly increase. Staphylococcus aureus and Staphylococcus epidermidis are the leading etiologic agents of orthopedic implant infection. Here we report on epidemiology of implant-related Staphylococcus infections in orthopedics, also referring to our experience, and focus on the crucial role of bacterial adhesins and on their ability to direct the pathogenesis process. Bacteria initiate implant infection by adhering to biomaterials. In the early steps of infection, adhesins mediate the specific interaction between microbial cells and the extracellular matrix proteins filming biomaterial surface. Then adhesin-mediated anchorage allows bacteria to cling to the biomaterial surface and to produce a biofilm that favors their ability to resist antibiotics. With the aim to prevent implant-related infections, anti-infective and infection-resistant biomaterials are being developed. The research for novel therapeutic strategies is incited by the emergence of antibiotic-resistant bacteria. Vaccines against the adhesins or antisense molecules against virulence genes can open a future in combating implant infections.


Asunto(s)
Infecciones Relacionadas con Prótesis/epidemiología , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/fisiología , Staphylococcus epidermidis/fisiología , Adhesinas Bacterianas/metabolismo , Adhesión Bacteriana , Biopelículas/crecimiento & desarrollo , Humanos , Procedimientos Ortopédicos/efectos adversos , Staphylococcus aureus/crecimiento & desarrollo , Staphylococcus aureus/patogenicidad , Staphylococcus epidermidis/crecimiento & desarrollo , Staphylococcus epidermidis/patogenicidad , Factores de Virulencia/metabolismo
19.
Int J Artif Organs ; 33(9): 575-81, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20963724

RESUMEN

Staphylococcus warneri is a coagulase negative Staphylococcus (CNS) commonly present in the flora of human epithelia and mucosal membranes. Over the last two decades, similarly to other CNS species, S. warneri has been reported as a new emerging pathogen, capable of causing serious infections usually in association with the presence of implant materials, but, at times, even in the absence of a foreign body and in patients considered immunocompetent. At present, there is still a lack of scientific data on the pathogenesis and epidemiology of this species. The present study investigated a collection of 26 clinical isolates derived from orthopedic infections, some associated with implant materials and others not. Automated ribotyping showed the existence of 5 distinct ribogroups. Except for the least numerous ribogroup consisting of a single isolate, all other ribogroups included at least one strain obtained from an infection not associated with implant materials, suggesting that putative virulence factors necessary for infections even in the absence of a foreign body could be transversal to most ribogroup categories. Orthopedic infections were found to involve S. warneri strains with low antibiotic resistance potential, differing in this respect from the strains isolated at neonatal intensive care units, where this species has been described to figure among the principal causative agents and exhibit an alarming profile of antibiotic resistance.


Asunto(s)
Procedimientos Ortopédicos/efectos adversos , Infecciones Relacionadas con Prótesis/microbiología , Staphylococcus/clasificación , Infección de la Herida Quirúrgica/microbiología , Antibacterianos/farmacología , ADN Bacteriano/aislamiento & purificación , Pruebas Antimicrobianas de Difusión por Disco , Farmacorresistencia Bacteriana , Humanos , Procedimientos Ortopédicos/instrumentación , Infecciones Relacionadas con Prótesis/tratamiento farmacológico , ARN Ribosómico/aislamiento & purificación , Ribotipificación , Staphylococcus/efectos de los fármacos , Staphylococcus/genética , Staphylococcus/aislamiento & purificación , Staphylococcus/patogenicidad , Infección de la Herida Quirúrgica/tratamiento farmacológico , Virulencia
20.
J Biomed Mater Res A ; 94(3): 825-32, 2010 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-20336749

RESUMEN

Staphylococcus aureus is the leading etiologic agent of orthopedic implant infections. It is endowed with the accessory gene regulator (agr) locus that modulates expression of many virulence genes. Four allelic groups of agr have been recognized within this bacterial species. Here, 200 S. aureus isolates from orthopedic implant infections, typed at the start depending on their agr group, were screened for the presence of adhesin and leukotoxin genes. Interestingly, specific virulence gene patterns emerged in association with agr groups. The most frequently observed agr groups, agr I and agr II, were associated with the presence of sdrE, fib (agr II more than agr I), fnbB (agr I more than agr II), and lukE/lukD (agr II more than agr I). The third more frequent agr group, agr III, differed clearly from agr I and II, exhibiting high prevalence of bbp, generally not harbored by agr I and II, and copresence of bbp with cna, whereas high prevalence of the tandem sdrE/fib marked definitely agr II (91% of agr II isolates), and, though less strictly, agr I, in which prevailed the peculiar fib/fnbB pattern. The only four isolates belonging to agr IV showed full copresence of bbp with fib. Results point out distinct patterns of virulence genes, which underlie distinct evolutive strategies associated to agr groups in S. aureus causing orthopedic implant infections.


Asunto(s)
Proteínas Bacterianas/genética , Polimorfismo Genético , Prótesis e Implantes , Infecciones Relacionadas con Prótesis/microbiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidad , Transactivadores/genética , Adhesinas Bacterianas/genética , Toxinas Bacterianas/genética , Humanos
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