Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 23
Filtrar
Más filtros

Bases de datos
Tipo del documento
Intervalo de año de publicación
1.
Neth Heart J ; 31(1): 29-35, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35781784

RESUMEN

BACKGROUND: In their latest guidelines for infective endocarditis (IE) (2015), the European Society of Cardiology (ESC) introduced the implementation of the Endocarditis Team (ET) to facilitate the management of IE. This study presents our experiences and the diagnostic and therapeutic impact of the ET on the management of IE. METHODS: From 2016-2020, data of all patients with suspected IE referred to the ET were prospectively collected. The final diagnosis was defined by the ET as either rejected, possible or definite IE. Diagnostic impact was scored as any change in initial diagnosis, the frequency of additional diagnostic tests advised by the ET and any change in diagnosis after these tests. Therapeutic impact was scored as any change in antibiotic therapy or change from conservative to invasive therapy or vice versa. RESULTS: A total of 321 patients (median age 67 [55-77] years, 71% male) were enrolled. The final diagnosis was rejected IE in 47 (15%), possible IE in 34 (11%) and definite IE in 240 (75%) patients. A change of initial diagnosis was seen in 53/321(17%) patients. Additional microbiological tests were advised in 69/321 (21%) patients, and additional imaging tests in 136/321 (42%) patients, which resulted in subsequent change in diagnosis in 23/321 (7%) patients. Any change in antibiotic treatment was advised in 135/321 (42%) patients, and change from initial conservative to additional surgical treatment in 15/321 (5%) patients. CONCLUSION: The ET had a clear impact on the therapeutic policy for patients with suspected IE and is useful in the management of this life-threatening disease. Broad implementation is warranted.

2.
Neth Heart J ; 28(12): 628-636, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32909198

RESUMEN

Because the occurrence of infective endocarditis (IE) continues to be associated with high mortality, a working group was created by the Dutch Society of Cardiology to examine how the most recent European Society of Cardiology (ESC) guidelines for IE management could be implemented most effectively in the Netherlands. In order to investigate current Dutch IE practices, the working group conducted a country-wide survey. Based on the results obtained, it was concluded that most ESC recommendations could be endorsed, albeit with some adjustments. For instance, the suggested pre-operative screening and treatment of nasal carriers of Staphylococcus aureus as formulated in the ESC guideline was found to be dissimilar to current Dutch practice, and was therefore made less restrictive. The recently adapted ESC diagnostic criteria for IE were endorsed, while the practical employment of the relevant diagnostic techniques was simplified in an adapted flowchart. In addition, the presence of a multidisciplinary, so-called 'endocarditis team' in tertiary centres was proposed as a quality indicator. An adapted flowchart specifically tailored to Dutch practice for microbiological diagnostic purposes was constructed. Lastly, the working group recommended the Stichting Werkgroep Antibioticabeleid (SWAB; Dutch Working Party on Antibiotic Policy) guidelines for IE treatment instead of the antibiotic regimens proposed by the ESC.

3.
Clin Exp Immunol ; 196(3): 374-382, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-30697694

RESUMEN

Infective endocarditis (IE) is the cardiac disease with the highest rates of mortality. New biomarkers that are able to identify patients at risk for death are required to improve patient management and outcome. This study aims to investigate if cytokines, chemokines and growth factors measured at IE diagnosis can predict mortality. Patients with definite IE, according to the Duke's modified criteria, were included. Using high-performance Luminex assay, 27 different cytokines, chemokines and growth factors were analyzed. Machine learning techniques were used for the prediction of death and subsequently creating a decision tree, in which the cytokines, chemokines and growth factors were analyzed together with C-reactive protein (CRP). Sixty-nine patients were included, 41 (59%) male, median age 54 [interquartile range (IQR) = 41-65 years] and median time between onset of the symptoms and diagnosis was 12 days (IQR = 5-30 days). The in-hospital mortality was 26% (n = 18). Proinflammatory cytokines interkeukin (IL)-15 and C-C motif chemokine ligand (CCL4) were found to predict death, adding value to CRP levels. The decision tree predicted correctly the outcome of 91% of the patients at hospital admission. The high-risk group, defined as CRP ≥ 72 mg/dL, IL-15 ≥ 5·6 fg/ml and CCL4 ≥ 6·35 fg/ml had an 88% in-hospital mortality rate, whereas the patients classified as low-risk had a mortality rate of 8% (P = < 0·001). Cytokines IL-15 and CCL4 were predictors of mortality in IE, adding prognostic value beyond that provided by CRP levels. Assessment of cytokines has potential value for clinical risk stratification and monitoring in IE patients.


Asunto(s)
Quimiocina CCL4/metabolismo , Endocarditis/diagnóstico , Interleucina-15/metabolismo , Adulto , Anciano , Biomarcadores/metabolismo , Proteína C-Reactiva/metabolismo , Toma de Decisiones Asistida por Computador , Endocarditis/inmunología , Endocarditis/mortalidad , Femenino , Mortalidad Hospitalaria , Humanos , Aprendizaje Automático , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo
4.
Transpl Infect Dis ; 15(6): E243-9, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24298985

RESUMEN

Treatment of cytomegalovirus (CMV) disease in transplant patients is challenging and, with antiviral resistance to first-line drugs, it remains uncertain which treatment algorithm to follow. Some data suggest that leflunomide, a pyrimidine synthesis inhibitor, can be used to treat resistant CMV infections. We report a 57-year-old CMV immunoglobulin-G (IgG)-seronegative woman, who received a bilateral lung transplant (LuTx) from a CMV IgG-positive donor with CMV primary disease. The CMV strain was genotypically resistant to ganciclovir, foscarnet, and cidofovir. After starting leflunomide as add-on therapy to a multidrug anti-CMV regimen, viral load declined substantially in 2 months without adverse events. This experience is discussed against the background of existing literature on the use of leflunomide as an anti-CMV agent in LuTx recipients.


Asunto(s)
Antivirales/uso terapéutico , Infecciones por Citomegalovirus/tratamiento farmacológico , Isoxazoles/uso terapéutico , Trasplante de Pulmón/efectos adversos , Citomegalovirus/efectos de los fármacos , Infecciones por Citomegalovirus/transmisión , Farmacorresistencia Viral , Quimioterapia Combinada , Femenino , Foscarnet/uso terapéutico , Ganciclovir/uso terapéutico , Humanos , Inmunoglobulinas/uso terapéutico , Leflunamida , Persona de Mediana Edad , Carga Viral
5.
BMJ Open ; 13(4): e068295, 2023 04 21.
Artículo en Inglés | MEDLINE | ID: mdl-37085305

RESUMEN

INTRODUCTION: A major knowledge gap in the treatment of complicated Staphylococcus aureus bacteraemia (SAB) is the optimal duration of antibiotic therapy. Safe shortening of antibiotic therapy has the potential to reduce adverse drug events, length of hospital stay and costs. The objective of the SAFE trial is to evaluate whether 4 weeks of antibiotic therapy is non-inferior to 6 weeks in patients with complicated SAB. METHODS AND ANALYSIS: The SAFE-trial is a multicentre, non-inferiority, open-label, parallel group, randomised controlled trial evaluating 4 versus 6 weeks of antibiotic therapy for complicated SAB. The study is performed in 15 university hospitals and general hospitals in the Netherlands. Eligible patients are adults with methicillin-susceptible SAB with evidence of deep-seated or metastatic infection and/or predictors of complicated SAB. Only patients with a satisfactory clinical response to initial antibiotic treatment are included. Patients with infected prosthetic material or an undrained abscess of 5 cm or more at day 14 of adequate antibiotic treatment are excluded. Primary outcome is success of therapy after 180 days, a combined endpoint of survival without evidence of microbiologically confirmed disease relapse. Assuming a primary endpoint occurrence of 90% in the 6 weeks group, a non-inferiority margin of 7.5% is used. Enrolment of 396 patients in total is required to demonstrate non-inferiority of shorter antibiotic therapy with a power of 80%. Currently, 152 patients are enrolled in the study. ETHICS AND DISSEMINATION: This is the first randomised controlled trial evaluating duration of antibiotic therapy for complicated SAB. Non-inferiority of 4 weeks of treatment would allow shortening of treatment duration in selected patients with complicated SAB. This study is approved by the Medical Ethics Committee VUmc (Amsterdam, the Netherlands) and registered under NL8347 (the Netherlands Trial Register). Results of the study will be published in a peer-reviewed journal. TRIAL REGISTRATION NUMBER: NL8347 (the Netherlands Trial Register).


Asunto(s)
Bacteriemia , Infecciones Estafilocócicas , Adulto , Humanos , Antibacterianos , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Bacteriemia/microbiología , Duración de la Terapia , Staphylococcus aureus , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto
6.
Eur J Clin Microbiol Infect Dis ; 30(6): 707-17, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21509478

RESUMEN

Autologous vaccines (short: autovaccines) have been used since the beginning of the 20th century to treat chronic staphylococcal infections, but their mechanisms of action are still obscure. This prospective pilot study involved four patients with furunculosis who were vaccinated with autologous formalin-killed Staphylococcus aureus cells. Vaccines were individually prepared from the infecting S. aureus strain and repeatedly injected subcutaneously in increasing doses over several months. We characterized the virulence gene repertoire and spa genotype of the infecting and colonising S. aureus strains. Serum antibody responses to secreted and surface-bound bacterial antigens were determined by two-dimensional immunoblotting and flow-cytometry based assays (Luminex). All patients reported clinical improvement. Molecular characterization showed that all strains isolated from one patient over time belonged to the same S. aureus clone. Already before treatment, there was robust antibody binding to a broad range of staphylococcal antigens. Autovaccination moderately boosted the IgG response to extracellular antigens in two patients, while the antibody response of the other two patients was not affected. Similarly, vaccination moderately enhanced the antibody response against some staphylococcal surface proteins, e.g. ClfA, ClfB, SdrD and SdrE. In summary, autovaccination only slightly boosted the pre-existing serum antibody response, predominantly to bacterial surface antigens.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Autovacunas/inmunología , Forunculosis/inmunología , Forunculosis/microbiología , Infecciones Estafilocócicas/inmunología , Vacunas Estafilocócicas/inmunología , Staphylococcus aureus/inmunología , Adulto , Autovacunas/administración & dosificación , Electroforesis en Gel Bidimensional , Femenino , Formaldehído , Humanos , Immunoblotting , Inmunoglobulina G/sangre , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Suero/química , Infecciones Estafilocócicas/microbiología , Vacunas Estafilocócicas/administración & dosificación , Staphylococcus aureus/aislamiento & purificación , Vacunas de Productos Inactivados/administración & dosificación , Vacunas de Productos Inactivados/inmunología , Adulto Joven
7.
Eur J Clin Microbiol Infect Dis ; 30(4): 521-6, 2011 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21086008

RESUMEN

Presently, several pneumococcal proteins are being evaluated as potential vaccine candidates. Here, we gather novel insights in the immunogenicity of PLY, PsaA, PspA, PspC, NanA, Hyl, PpmA, SlrA, Eno, IgA1-protease, PdBD, BVH-3, SP1003, SP1633, SP1651, SP0189 and SP0376. We developed a multiplex bead-based immunoassay (xMAP(®) Technology, Luminex Corporation) to simultaneously quantify antibodies against these 17 pneumococcal proteins in serum. The median fluorescence intensity (MFI) values obtained for human pooled serum with the multiplex assay were between 82% and 111% (median 94%) of those obtained with the singleplex assays. For IgG, the coefficient of variation (CV) in serum ranged from 2% to 9%, for IgA, the CV ranged from 3% to 14% and for IgM, the CV ranged from 11% to 15%. Using this immunoassay, we showed that anti-pneumococcal antibody levels exhibited extensive inter-individual variability in young children suffering from invasive pneumococcal disease. All proteins, including the proteins with, as yet, unknown function, were immunogenic. In conclusion, the multiplex Streptococcus pneumoniae immunoassay based on proteins is reproducible. This assay can be used to monitor anti-S. pneumoniae antibody responses in a material- and time-saving manner.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Proteínas Bacterianas/inmunología , Infecciones Neumocócicas/inmunología , Streptococcus pneumoniae/inmunología , Proteínas Bacterianas/genética , Niño , Preescolar , Citometría de Flujo , Humanos , Inmunoensayo/métodos , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Meningitis Neumocócica/inmunología , Meningitis Neumocócica/microbiología , Infecciones Neumocócicas/microbiología , Polisacáridos Bacterianos/genética , Polisacáridos Bacterianos/inmunología , Reproducibilidad de los Resultados
8.
Eur J Clin Microbiol Infect Dis ; 29(5): 509-18, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20186449

RESUMEN

Expanding knowledge on the humoral immune response in Staphylococcus aureus-infected patients is a mandatory step in the development of vaccines and immunotherapies. Here, we present novel insights into the antibody responses following S. aureus bacteremia. Fifteen bacteremic patients were followed extensively from diagnosis onwards (median 29 days, range 9-74). S. aureus strains (median 3, range 1-6) and serial serum samples (median 16, range 6-27) were collected. Strains were genotyped by pulsed-field gel electrophoresis (PFGE) and genes encoding 19 staphylococcal proteins were detected by polymerase chain reaction (PCR). The levels of IgG, IgA, and IgM directed to these proteins were determined using bead-based flow cytometry. All strains isolated from individual patients were PFGE-identical. The genes encoding clumping factor (Clf) A, ClfB, and iron-responsive surface-determinant (Isd) A were detected in all isolates. Antigen-specific IgG levels increased more frequently than IgA or IgM levels. In individual patients, different proteins induced an immune response and the dynamics clearly differed. Anti-ClfB, anti-IsdH, and anti-fibronectin-binding protein A IgG levels increased in 7 of 13 adult patients (p < 0.05). The anti-IsdA IgG level increased in 12 patients (initial to peak level: 1.13-10.72 fold; p < 0.01). Peak level was reached 7-37 days after diagnosis. In a bacteremic 5-day-old newborn, antistaphylococcal IgG levels declined from diagnosis onwards. In conclusion, each bacteremic patient develops a unique immune response directed to different staphylococcal proteins. Therefore, vaccines should be based on multiple components. IsdA is immunogenic and, therefore, produced in nearly all bacteremic patients. This suggests that IsdA might be a useful component of a multivalent staphylococcal vaccine.


Asunto(s)
Bacteriemia/inmunología , Infecciones Estafilocócicas/inmunología , Staphylococcus aureus/inmunología , Adulto , Anciano , Anticuerpos Antibacterianos/sangre , Anticuerpos Antibacterianos/inmunología , Bacteriemia/microbiología , Preescolar , Análisis por Conglomerados , Electroforesis en Gel de Campo Pulsado , Femenino , Humanos , Inmunidad Humoral/inmunología , Isotipos de Inmunoglobulinas/sangre , Isotipos de Inmunoglobulinas/inmunología , Recién Nacido , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/genética , Estadísticas no Paramétricas , Virulencia/genética
9.
PLoS One ; 15(9): e0239751, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32991591

RESUMEN

BACKGROUND: Antimicrobial stewardship (AMS) programs promote appropriate use of antimicrobials and reduce antimicrobial resistance. Technological developments have resulted in smartphone applications (apps) facilitating AMS. Yet, their impact is unclear. OBJECTIVES: Systematically review AMS apps and their impact on prescribing by physicians treating in-hospital patients. DATA SOURCES: EMBASE, MEDLINE (Ovid), Cochrane Central, Web of Science and Google Scholar. STUDY ELIGIBILITY CRITERIA: Studies focusing on smartphone or tablet apps and antimicrobial therapy published from January 2008 until February 28th 2019 were included. PARTICIPANTS: Physicians treating in-hospital patients. INTERVENTIONS: AMS apps. METHODS: Systematic review. RESULTS: Thirteen studies met the eligibility criteria. None was a randomized controlled trial. Methodological study quality was considered low to moderate in all but three qualitative studies. The primary outcomes were process indicators, adherence to guidelines and user experience. Guidelines were more frequently accessed by app (53.0% - 89.6%) than by desktop in three studies. Adherence to guidelines increased (6.5% - 74.0%) significantly for several indications after app implementation in four studies. Most users considered app use easy (77.4%->90.0%) and useful (71.0%->90%) in three studies and preferred it over guideline access by web viewer or booklet in two studies. However, some physicians regarded app use adjacent to colleagues or patients unprofessional in three qualitative studies. Susceptibility to several antimicrobials changed significantly post-intervention (from 5% decrease to 10% - 14% increase) in one study. CONCLUSIONS: Use of AMS apps seems to promote access to and knowledge of antimicrobial prescribing policy, and increase adherence to guidelines in hospitals. However, this has been assessed in a limited number of studies and for specific indications. Good quality studies are necessary to properly assess the impact of AMS apps on antimicrobial prescribing. To improve adherence to antimicrobial guidelines, use of AMS apps could be considered.


Asunto(s)
Antiinfecciosos/uso terapéutico , Programas de Optimización del Uso de los Antimicrobianos/métodos , Aplicaciones Móviles , Médicos/psicología , Pautas de la Práctica en Medicina/normas , Programas de Optimización del Uso de los Antimicrobianos/normas , Adhesión a Directriz/tendencias , Hospitales , Humanos
10.
Neth J Med ; 77(3): 116-118, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-31012429

RESUMEN

Invasive meningococcal disease is associated with significant mortality. Classic presentation consists of high fever, headache and neck stiffness. Neisseria meningitidis serogroup W may present with atypical symptoms, which complicates recognition. Furthermore, it is associated with a high case fatality rate.


Asunto(s)
Diarrea/microbiología , Infecciones Meningocócicas/complicaciones , Infecciones Meningocócicas/microbiología , Neisseria meningitidis Serogrupo W-135 , Sepsis/microbiología , Diagnóstico Diferencial , Diarrea/diagnóstico , Femenino , Humanos , Infecciones Meningocócicas/diagnóstico , Sepsis/diagnóstico , Adulto Joven
11.
Clin Cancer Res ; 3(5): 805-15, 1997 May.
Artículo en Inglés | MEDLINE | ID: mdl-9815753

RESUMEN

CD44 forms a group of transmembranous glycoproteins formed by alternative splicing of a single mRNA. The expression of v6 exon-containing variants correlates with metastasis and poor prognosis in a number of malignancies. The distribution and prognostic value of CD44s, CD44v5, and CD44v6 were studied immunohistochemically in the radical prostatectomy specimens of 97 patients with prostate cancer and in 12 lymph node metastases. The mean follow-up period was 84 months. The percentage of CD44-immunoreactive cells was scored semiquantitatively. CD44 mRNA expression was studied in nine prostate cancer and eight benign prostatic hyperplasia (BPH) samples by reverse transcriptase-PCR. Benign prostatic glands almost always expressed CD44s, CD44v6, and, at a lower intensity, CD44v5. CD44 scores decreased from low- to high-grade prostatic intraepithelial neoplasia. CD44s, CD44v5, and CD44v6 were expressed in 86, 23, and 69% of the adenocarcinomas, respectively. Gleason sum score (GSS) and pT stage were correlated inversely with CD44s and CD44v6 scores. CD44 was not found in the lymph node metastatic tumor cells. At the mRNA level, 89% of the tumors and all BPH samples expressed CD44s. CD44v6-v10 mRNA was present in 44 and 75% of the tumors and BPH samples, respectively. Loss of CD44s and CD44v6 predicted an adverse prognosis at univariate analysis. The independent prognosticators identified by multivariate analysis were: GSS, pT stage, and CD44s for clinical progression; GSS and CD44s for prostate-specific antigen progression; and GSS for tumor-specific survival. Loss of CD44s expression in prostate adenocarcinoma predicts a poor prognosis, independent of stage and grade.


Asunto(s)
Receptores de Hialuranos/genética , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/cirugía , Transcripción Genética , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Exones , Humanos , Receptores de Hialuranos/análisis , Inmunohistoquímica , Metástasis Linfática , Masculino , Estadificación de Neoplasias , Valor Predictivo de las Pruebas , Pronóstico , Prostatectomía/métodos , Hiperplasia Prostática/genética , Hiperplasia Prostática/patología , Hiperplasia Prostática/cirugía , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/mortalidad , Isoformas de Proteínas/análisis , Isoformas de Proteínas/genética , ARN Mensajero/genética , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Análisis de Supervivencia , Factores de Tiempo
13.
Br J Pharmacol ; 141(5): 842-50, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-14769779

RESUMEN

1. The purine nucleotide adenosine-5'-triphosphate (ATP) exerts pronounced effects on the cardiovascular system. The mechanism of action of the vasodilator response to ATP in humans has not been elucidated yet. The proposed endothelium-derived relaxing factors (EDRFs) were studied in a series of experiments, using the perfused forearm technique. 2. Adenosine 5'-triphosphate (0.2, 0.6, 6 and 20 nmol dl(-1) forearm volume min(-1)) evoked a dose-dependent forearm vasodilator response, which could not be inhibited by separate infusion of the nonselective COX inhibitor indomethacin (5 microg dl(-1) min(-1), n=10), the blocker of Na(+)/K(+)-ATPase ouabain (0.2 microg dl(-1) min(-1), n=8), the blocker of K(Ca) channels tetraethylammonium chloride (TEA, 0.1 microg dl(-1) min(-1), n=10), nor by the K(ATP)-channel blocker glibenclamide (2 microg dl(-1) min(-1), n=10). All blockers, except glibenclamide, caused a significant increase in baseline vascular tone. The obtained results might be due to compensatory actions of unblocked EDRFs. Combined infusion of TEA, indomethacin and l-NMMA (n=6) significantly increased the baseline forearm vascular resistance. The ATP-induced relative decreases in forearm vascular resistance were 48+/-5, 67+/-3, 88+/-2, and 92+/-2% in the absence and 23+/-7, 62+/-4, 89+/-2, and 93+/-1% in the presence of the combination of TEA, indomethacin and l-NMMA (P<0.05, repeated-measures ANOVA, n=6). A similar inhibition was obtained for sodium nitroprusside (SNP, P<0.05 repeated-measures ANOVA, n=6), indicating a nonspecific interaction due to the blocker-induced vasoconstriction. 3. ATP-induced vasodilation in the human forearm cannot be inhibited by separate infusion of indomethacin, ouabain, glibenclamide or TEA, or by a combined infusion of TEA, indomethacin, and l-NMMA. Endothelium-independent mechanisms and involvement of unblocked EDRFs, such as CO, might play a role, and call for further studies.


Asunto(s)
Adenosina Trifosfato/farmacología , Músculo Esquelético/irrigación sanguínea , Músculo Esquelético/efectos de los fármacos , Vasodilatación/efectos de los fármacos , Adolescente , Adulto , Análisis de Varianza , Relación Dosis-Respuesta a Droga , Femenino , Antebrazo/irrigación sanguínea , Humanos , Indometacina/farmacología , Masculino , Ouabaína/farmacología , Vasodilatación/fisiología
15.
Clin Microbiol Infect ; 17(3): 343-8, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20370801

RESUMEN

The Staphylococcus aureus immune evasion cluster (IEC), located on ß-haemolysin-converting bacteriophages (ßC-Φs), encodes the immune-modulating proteins chemotaxis inhibitory protein, staphylococcal complement inhibitor (SCIN), staphylococcal enterotoxin A and staphylokinase. Its precise role in S. aureus colonization is unclear. We studied the presence of the IEC-carrying bacteriophages in human and animal S. aureus isolates, using PCR for the gene encoding SCIN (scn). Human isolates were obtained by collecting serial nasal swabs from 21 persistent carriers. S. aureus strains from 19 (90%) persistent carriers contained an IEC that was present and indistinguishable in 95% of cases at all five sampling moments over a 3-month period. Of the 77 infectious animal strains included in the study, only 26 strains (34%) were IEC-positive. Integration of these IEC-positive strains into an amplified fragment length polymorphism genotype database showed that 24 of 53 (45%) strains were human-associated and only two of 24 (8%) were 'true' animal isolates (p < 0.001). The high prevalence and stability of IEC-carrying ßC-Φs in human strains suggested a role for these ßC-Φs in human nasal colonization. To test this hypothesis, 23 volunteers were colonized artificially with S. aureus strain NCTC 8325-4 with or without the IEC type B-carrying ßC-Φ13. Intranasal survival was monitored for 28 days after inoculation. The strain harbouring ßC-Φ13 was eliminated significantly faster (median 4 days; range 1-14 days) than the strain without ßC-Φ13 (median 14 days; range 2-28 days; p 0.011). In conclusion, although IEC-carrying ßC-Φs are highly prevalent among human colonizing S. aureus strains, they are not essential in the first stages of S. aureus nasal colonization.


Asunto(s)
Genes Virales , Evasión Inmune/genética , Mucosa Nasal/microbiología , Infecciones Estafilocócicas/virología , Fagos de Staphylococcus/genética , Staphylococcus aureus/virología , Adulto , Animales , Proteínas Bacterianas/genética , Toxinas Bacterianas/metabolismo , Recuento de Colonia Microbiana , Enterotoxinas/genética , Femenino , Proteínas Hemolisinas/metabolismo , Humanos , Masculino , Metaloendopeptidasas/genética , Persona de Mediana Edad , Familia de Multigenes , Mascotas , Esfingomielina Fosfodiesterasa/metabolismo , Staphylococcus aureus/genética , Staphylococcus aureus/aislamiento & purificación , Adulto Joven
16.
Clin Microbiol Infect ; 17(12): 1840-4, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21883660

RESUMEN

It remains largely unknown which factors determine the clinical outcome of human metapneumovirus (HMPV) infections. The aim of the present study was to analyse whether exposure to bacterial pathogens can influence HMPV infections. From 57 children, serum samples and colonization data for Haemophilus influenzae, Moraxella catarrhalis, Staphylococcus aureus and Streptococcus pneumoniae were collected at 1.5, 6, 14 and 24 months of age. Seroconversion rates to HMPV were determined and related to bacterial carriage. Frequent nasopharyngeal carriage (≥2 times in the first 2 years of life) of S. pneumoniae, but not of the other three pathogens, was associated with increased seroconversion rates of infants to HMPV at the age of 2 years (frequently vs. less exposed, 93% vs. 59%; p <0.05). Subsequently, the susceptibility of well-differentiated normal human bronchial epithelial cells (wd-NHBE) pre-incubated with bacterial pathogens to in vitro HMPV infection was evaluated. Pre-incubation of wd-NHBE with S. pneumoniae resulted in increased susceptibility to infection with HMPV-enhanced green fluorescent protein (EGFP), as determined by enumeration of EGFP-positive cells. This was not the case for cells pre-incubated with H. influenzae, M. catarrhalis on S. aureus. We conclude that exposure to S. pneumoniae can modulate HMPV infection.


Asunto(s)
Anticuerpos Antivirales/sangre , Portador Sano , Susceptibilidad a Enfermedades , Metapneumovirus/aislamiento & purificación , Infecciones por Paramyxoviridae/epidemiología , Infecciones Neumocócicas/complicaciones , Streptococcus pneumoniae/patogenicidad , Preescolar , Haemophilus influenzae/aislamiento & purificación , Haemophilus influenzae/patogenicidad , Humanos , Lactante , Metapneumovirus/inmunología , Moraxella catarrhalis/aislamiento & purificación , Moraxella catarrhalis/patogenicidad , Nasofaringe/microbiología , Infecciones por Paramyxoviridae/inmunología , Infecciones por Paramyxoviridae/virología , Staphylococcus aureus/aislamiento & purificación , Staphylococcus aureus/patogenicidad , Streptococcus pneumoniae/aislamiento & purificación
17.
Clin Microbiol Infect ; 16(8): 1312-7, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19832714

RESUMEN

In order to develop novel antistaphylococcal strategies, understanding the determinants of carriage and how humans respond to Staphylococcus aureus exposure is essential. Here, the primary S. aureus-specific humoral immune response and its association with nasal colonization was studied in young children. Sera from 57 colonized or non-colonized children, serially collected at birth and at 6, 14 and 24 months, were analysed for IgG, IgA and IgM binding to 19 staphylococcal proteins, using flow cytometry-based technology. The antibody responses showed extensive inter-individual variability. On average, the levels of antistaphylococcal IgA and IgM increased from birth until the age of 2 years (p <0.05), whereas the levels of IgG decreased (p <0.001). Placentally transferred maternal IgG did not protect against colonization. In colonized children, IgG and IgA levels for a number of proteins were higher than in non-colonized children. At both 14 and 24 months, the levels of IgG against chemotaxis inhibitory protein of S. aureus (at 24 months; median fluorescence intensity, 4928 vs. 24, p <0.05), extracellular fibrinogen-binding protein (987 vs. 604, p <0.05), and iron-responsive surface determinant H (62 vs. 5, p <0.05) were significantly higher in colonized children. The levels of IgA against CHIPS, IsdH and IsdA were higher (p <0.05). Therefore, CHIPS, Efb, IsdA and IsdH seem to play a role in nasal colonization of young children.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Portador Sano/inmunología , Mucosa Nasal/microbiología , Infecciones Estafilocócicas/inmunología , Staphylococcus aureus/inmunología , Factores de Edad , Antígenos Bacterianos/inmunología , Proteínas Bacterianas/inmunología , Portador Sano/microbiología , Preescolar , Proteínas Inactivadoras de Complemento/inmunología , Citometría de Flujo/métodos , Humanos , Inmunidad Materno-Adquirida , Inmunoglobulina A/sangre , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Lactante , Recién Nacido , Receptores de Superficie Celular/inmunología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/aislamiento & purificación
18.
Urol Res ; 25(6): 373-84, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9443645

RESUMEN

Understaging is commonly associated with therapeutic failure of surgical intervention in apparently localized prostate cancers. Methods that specifically detect prostate cancer cells in the circulation may be able to identify metastatic cancers and thus aid in the selection of the most adequate therapy. The high sensitivity and specificity of the reverse transcriptase-polymerase chain reaction (RT-PCR) encouraged various groups to investigate the mRNA expression of prostate-specific markers in the peripheral blood of patients with prostate cancer. However, probably due to methodological differences, many contradictory results have been obtained with the markers studied so far: prostate-specific antigen (PSA) and prostate-specific membrane antigen (PSM). For this reason, clinical decisions should not be based yet on RT-PCR results. Future research and long-term follow-up on the patients may point out whether RT-PCR assays, following appropriate standardization, will have an additive value in prostate cancer staging and in prediction of tumor progression.


Asunto(s)
Antígenos de Superficie , Biomarcadores de Tumor/sangre , Células Neoplásicas Circulantes , Reacción en Cadena de la Polimerasa , Neoplasias de la Próstata/patología , Carboxipeptidasas/sangre , Glutamato Carboxipeptidasa II , Humanos , Masculino , Antígeno Prostático Específico/sangre , Neoplasias de la Próstata/sangre
19.
Int J Cancer ; 80(3): 439-43, 1999 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-9935187

RESUMEN

Down-regulation of the cell-surface adhesion molecule CD44 has been suggested to play an important role in tumor progression and metastasis of prostate cancer. CD44 is encoded by a gene that contains a CpG-rich region (CpG island) in its 5' regulatory sequence. We tried to assess whether hypermethylation of this region is the mechanism responsible for CD44 transcriptional inactivation. A panel of prostatic-carcinoma cell lines, Du145, LNCaP, PC3, PC346C and TSU, was analyzed for CD44 mRNA and protein expression. Du145, PC3 and TSU were positive for CD44, whereas in LNCaP and PC346C both CD44 mRNA and protein expression was suppressed. Methylation-sensitive restriction-enzyme analysis of genomic DNA showed that, in contrast to the CD44-positive cell lines, the CD44-negative lines were hypermethylated in the CD44 promoter CpG island. Furthermore, treatment of a PC346C culture with the demethylating agent 5-azacytidine resulted in re-expression of CD44 mRNA. It is concluded that hypermethylation of the CD44 5' promoter region is one of the mechanisms by which CD44 expression is down-regulated in prostatic-carcinoma cell lines.


Asunto(s)
Islas de CpG/fisiología , Metilación de ADN , ADN de Neoplasias/metabolismo , Receptores de Hialuranos/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias de la Próstata/metabolismo , Antimetabolitos Antineoplásicos/farmacología , Azacitidina/farmacología , Regulación hacia Abajo , Humanos , Receptores de Hialuranos/genética , Masculino , Proteínas de Neoplasias/genética , Neoplasias de la Próstata/genética , ARN Mensajero/metabolismo , Células Tumorales Cultivadas
20.
Biochem J ; 315 ( Pt 3): 901-8, 1996 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-8645175

RESUMEN

Transglutaminases (TGases) are calcium-dependent enzymes catalysing the post-translational cross-linking of proteins. In the prostate at least two TGases are present, the ubiquitously expressed tissue-type TGase (TGC), and a prostate-restricted TGase (TGP). This paper deals with the molecular cloning and characterization of the cDNA encoding the human prostate TGase (hTGP). For this purpose we have screened a human prostate cDNA library with a probe from the active-site region of TGC. The largest isolated cDNA contained an open reading frame encoding a protein of 684 amino acids with a predicted molecular mass of 77 kDa as confirmed by in vitro transcription-translation and subsequent SDS/PAGE. The hTGP gene was tissue-specifically expressed in the prostate, yielding an mRNA of approx. 3.5 kb. Furthermore, a 3-fold androgen-induced upregulation of hTGP mRNA expression has been demonstrated in the recently developed human prostate cancer cell line, PC346C. Other well established human prostate cancer cell lines, LNCaP and PC-3, showed no detectable hTGP mRNA expression on a Northern bolt. The gene coding for prostate TGase was assigned to chromosome 3.


Asunto(s)
Andrógenos/metabolismo , Próstata/enzimología , Transglutaminasas/metabolismo , Secuencia de Aminoácidos , Animales , Secuencia de Bases , Mapeo Cromosómico , Cromosomas Humanos Par 3/genética , Clonación Molecular , Cricetinae , Sondas de ADN/genética , ADN Complementario/genética , Femenino , Regulación Enzimológica de la Expresión Génica , Humanos , Células Híbridas , Masculino , Ratones , Datos de Secuencia Molecular , Neoplasias de la Próstata/enzimología , Neoplasias de la Próstata/genética , Homología de Secuencia de Aminoácido , Distribución Tisular , Transglutaminasas/genética , Células Tumorales Cultivadas
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA