Fernando Vazquez | Instituto Universitario Hospital Italiano (original) (raw)
Papers by Fernando Vazquez
![Research paper thumbnail of [Venous thromboembolic prophylaxis. Guidelines for adults in Argentina]](https://attachments.academia-assets.com/43989358/thumbnails/1.jpg)
](Medicina, 2013
The venous thromboembolic disease (VTD) in adults has a high morbidity and mortality. It can be a... more The venous thromboembolic disease (VTD) in adults has a high morbidity and mortality. It can be also associated to disabling chronic conditions. In spite of this, prophylaxis in healthcare assistance is still underused. In this article, the available evidence in thromboprophylaxis was analyzed to offer recommendations (1) or suggestions (2) classified according to different levels of evidence (A, B or C). Different medical scenarios and types of thromboprophylaxis were analyzed. In major orthopedic surgeries low molecular weight heparins, LMWH, inhibitors of the Xa and IIa factors are recommended (1B) to be started during hospitalization and continued for 35 days in hip replacement surgery and for 10 days in total knee replacement surgery. Knee arthroscopy and spine surgery do not require pharmacologic treatment (2B) unless the patient has other risks factors for thrombosis. In such cases, LMWH are recommended. Non-surgical patients who have at least one risk factor should receive L...
Medicina, 2004
Recurrent aseptic meningitis (RAM) infrequent in elderly patients and generally secondary to drug... more Recurrent aseptic meningitis (RAM) infrequent in elderly patients and generally secondary to drugs. Its association with rheumatologic diseases is also seldom reported in the elderly. Sjögren Syndrome (SS) sometimes affects the central nervous system, but the association between recurrent meningitis and SS is rare, specially in this age-group. We present an 88 year-old auto-valid patient, with a history of xerostomia, xerophthalmia, Raynaud, dysphagia, and recurrent parotid enlargement. In 2001 she developed a lymphocytic meningitis with a complete remission. A year later, she developed again an aseptic lymphocytic meningitis. We ruled out infectious causes. We found a FAN titer 1/160 with a nucleolar-mottled pattern, positive anti Ro and anti RNP antibodies and a positive lupus anticoagulant. We confirmed the ocular dryness and the lip biopsy was compatible with the diagnosis of SS. She had a good outcome with a complete remission without treatment in 10 days. We believe that this ...
International Journal of Environmental Research and Public Health, 2014
The purpose of this study was to identify subgroups of university students with the highest likel... more The purpose of this study was to identify subgroups of university students with the highest likelihood of remaining at elevated levels of depressive symptoms six months following the receipt of a depressive prevention intervention on the basis of known risk factors and participation in one of two depression prevention programs. Data from a randomized controlled trial evaluating depression prevention among 133 college students with elevated depressive symptoms were analyzed. Participants were randomized to a cognitive-behavioral or relaxation training group preventive intervention. Classification tree analysis showed that older age was the strongest risk factor for persistently elevated depression. Additional risk factors were: (1) for younger students, fewer daily pleasant activities; (2) for those with higher level of pleasant activities, higher level of stressful events; and (3) for those with higher level of stressful events, lower assertiveness. Results offer directions for prevention foci, identify specific subgroups of college students to target for depression prevention efforts, and suggest that research aim to help older, non-traditional students or graduating students manage the transition from college to the work force.
Clinical Lymphoma Myeloma and Leukemia, 2012
![Research paper thumbnail of [Venous thromboembolic prophylaxis. Guidelines for adults in Argentina]](https://attachments.academia-assets.com/44082988/thumbnails/1.jpg)
](The venous thromboembolic disease (VTD) in adults has a high morbidity and mortality. It can be a... more The venous thromboembolic disease (VTD) in adults has a high morbidity and mortality. It can be also associated to disabling chronic conditions. In spite of this, prophylaxis in healthcare assistance is still underused. In this article, the available evidence in thromboprophylaxis was analyzed to offer recommendations (1) or suggestions (2) classified according to different levels of evidence (A, B or C). Different medical scenarios and types of thromboprophylaxis were analyzed. In major orthopedic surgeries low molecular weight heparins, LMWH, inhibitors of the Xa and IIa factors are recommended (1B) to be started during hospitalization and continued for 35 days in hip replacement surgery and for 10 days in total knee replacement surgery. Knee arthroscopy and spine surgery do not require pharmacologic treatment (2B) unless the patient has other risks factors for thrombosis. In such cases, LMWH are recommended. Non-surgical patients who have at least one risk factor should receive L...
Resumen El mieloma múltiple (MM) es una enfermedad maligna caracterizada por una proliferación cl... more Resumen El mieloma múltiple (MM) es una enfermedad maligna caracterizada por una proliferación clonal de células plasmáticas atípicas en la médula ósea, que produce una inmunoglobulina (Ig) con estructura homogénea en la sangre y/o en la orina (cadenas livianas). El compromiso del parénquima hepático con masa ocupante en los pacientes con MM es excepcional. Describimos 3 casos clínicos conirmados histológicamente. La ecografía y la tomografía computarizada tienen una sensibilidad intermedia y las imágenes no son patognomónicas, por lo tanto es necesaria la conirmación a través de la biopsia. Se desconoce la implicancia pronóstica de este hallazgo.
Medicina
Resumen El mieloma múltiple (MM) es una enfermedad maligna caracterizada por una proliferación cl... more Resumen El mieloma múltiple (MM) es una enfermedad maligna caracterizada por una proliferación clonal de células plasmáticas atípicas en la médula ósea, que produce una inmunoglobulina (Ig) con estruc- tura homogénea en la sangre y/o en la orina (cadenas livianas). El compromiso del parénquima hepático con masa ocupante en los pacientes con MM es excepcional. Describimos 3 casos clínicos confirmados histológi- camente. La ecografía y la tomografía computarizada tienen una sensibilidad intermedia y las imágenes no son patognomónicas, por lo tanto es necesaria la confirmación a través de la biopsia. Se desconoce la implicancia pronóstica de este hallazgo. Palabras clave: mieloma múltiple, mieloma extramedular, mieloma hepático, compromiso hepático, gammapatía monoclonal Abstract Nodular hepatic lesions secondary to multiple myeloma. Multiple myeloma is characterized by the neoplastic proliferation of a single clone of plasma cells producing a monoclonal immunoglobulin. Myelomatous nod...
Medicina
Resumen La meningitis aséptica recurrente (MAR) en ancianos es rara y generalmente es secundaria ... more Resumen La meningitis aséptica recurrente (MAR) en ancianos es rara y generalmente es secundaria a drogas.
Since the introduction of computed tomography pulmonary angiography, isolated subsegmental pulmon... more Since the introduction of computed tomography pulmonary angiography, isolated subsegmental pulmonary embolism has become a commonly recognized clinical problem, but its clinical relevance remains unclear. The objective of the present study was to evaluate the extent to which the simplified Wells score discriminates between patients with varying levels of risk of complications after presenting with subsegmental pulmonary embolism. Retrospective cohort study. Patients included had subsegmental pulmonary embolism (1 or multiple emboli limited to subsegmental arteries). Primary explanatory variable was the simplified Wells score, categorized as high (>4) or low (≤4). The primary outcome was time to death or new venous thromboembolism. Kaplan-Meier techniques and Cox regression analysis were used to compare the survival experience of patients with high versus low Wells score with and without adjustment for active malignancy, age, Charlson score, previous venous thromboembolism, and previous major surgery in the last 30 days. Seventy-nine patients with subsegmental pulmonary embolism were included. Patients with a high Wells score had a 4-fold increased risk of the composite outcome (hazard ratio = 4.2, 95% confidence interval [CI] = 2.0-8.9, P < .001). Other covariates significantly associated with increased risk in univariate analyses included active malignancy, a low serum albumin, and an increased Charlson score. In multivariate Cox regression analyses adjusting for these other factors, a high Wells score remained significant (hazard ratio 5.5, 95% CI 2.4-12.6, P < .001). High Wells score is associated with death or new venous thromboembolism during follow-up among patients with subsegmental pulmonary embolism. ClinicalTrials.gov number, NCT01372514.
Journal of Immunoassay and Immunochemistry
A chemiluminescent sandwich ELISA test has been developed for the detection and quantitation of p... more A chemiluminescent sandwich ELISA test has been developed for the detection and quantitation of pneumolysin. The test is based on a mouse monoclonal as the capture antibody and on rabbit polyclonal IgGs as detection antibodies, in combination with an anti-rabbit IgG alkaline phosphatase conjugate. The estimated detection limit of the purified recombinant toxin in phosphate-buffered saline with 0.05% Triton X-100 is around 5 pg ml(-1), with averaged intra- and inter-assay variation coefficients of 7% and 13.5%, respectively. The assay has been applied to the quantitation of pneumolysin in pneumococcal isolates, providing, for the first time, a direct measurement of the amount of the toxin produced by different strains, a variation has been found in their pneumolysin content. The test is highly specific as no other purified toxins or human pneumonia- or meningitis-associated bacteria yielded false-positive results. This specific and highly sensitive method could help in the diagnosis ...
Enfermedades Infecciosas y Microbiología Clínica
The morbidity and mortality rates associated with Streptococcus pneumoniae remain very high world... more The morbidity and mortality rates associated with Streptococcus pneumoniae remain very high worldwide. The virulence of this bacterium is largely dependent on its polysaccharide capsule, which is quite heterogeneous and represents a serious obstacle for designing effective vaccines. However, it has been demonstrated that numerous protein virulence factors are involved in the pathogenesis of pneumococcal disease. An important related finding from experimental animal models is that non-capsulated strains of pneumococci are protective against capsulated ones. Hence, new vaccine designs are focused on the surface proteins (e. g., PspA and PspC) and on the cytolysin, pneumolysin. Moreover, several virulence factors have potential value for pneumococcal diagnosis by urinalysis. In this paper, we review the virulence factors involved in bacteria-host interactions, and the new developments in vaccines and diagnostic methods.
Respiratory research
Intranasal inoculation of Streptococcus pneumoniae D39 serotype 2 causes fatal pneumonia in mice.... more Intranasal inoculation of Streptococcus pneumoniae D39 serotype 2 causes fatal pneumonia in mice. The cytotoxic and inflammatory properties of pneumolysin (PLY) have been implicated in the pathogenesis of pneumococcal pneumonia. To examine the role of PLY in this experimental model we performed ELISA assays for PLY quantification. The distribution patterns of PLY and apoptosis were established by immunohistochemical detection of PLY, caspase-9 activity and TUNEL assay on tissue sections from mice lungs at various times, and the results were quantified with image analysis. Inflammatory and apoptotic cells were also quantified on lung tissue sections from antibody treated mice. In bronchoalveolar lavages (BAL), total PLY was found at sublytic concentrations which were located in alveolar macrophages and leukocytes. The bronchoalveolar epithelium was PLY-positive, while the vascular endothelium was not PLY reactive. The pattern and extension of cellular apoptosis was similar. Anti-PLY ...
Infection and Immunity
We have produced a panel of monoclonal antibodies to pneumolysin, the membrane-damaging toxin fro... more We have produced a panel of monoclonal antibodies to pneumolysin, the membrane-damaging toxin from Streptococcus pneumoniae. We have used these antibodies to identify three regions of the toxin sequence that are involved in the lytic mechanism of this toxin. Two of these sites probably form the cell binding site of this toxin. Antibodies to the third site inhibit the lytic action of this toxin but not the binding of this toxin to cells. This site is engaged in the oligomerization process involved in the formation of pores in cell membranes. Two of these epitopes are also present in the related toxin perfringolysin O.
Clinical Microbiology and Infection
Streptococcus pneumoniae infections are often difficult to diagnose accurately, as it is not unco... more Streptococcus pneumoniae infections are often difficult to diagnose accurately, as it is not uncommon for clinical samples to be culture-negative, particularly after antibiotic administration. The rapid Binax NOW S. pneumoniae urinary antigen test lacks specificity in children, owing to pneumococcal antigen reactions in children who are nasopharyngeal carriers of S. pneumoniae. A western blot assay with a specific polyclonal antibody was developed for direct detection of the putative proteinase maturation protein A (PpmA) in urine samples from children with pneumococcal infections. The sensitivity and specificity of the assay were 66.7% and 100%, respectively. Previous antibiotic treatment or S. pneumoniae nasopharyngeal colonization did not affect PpmA antigenuria. Results also demonstrated the presence of PpmA cross-reactive epitopes in commensal bacteria that co-colonize the nasopharyngeal niche, although the non-pneumococcal cross-reactive protein(s) did not interfere with the d...
Enfermedades Infecciosas y Microbiología Clínica
Haemophilus spp. had been previously suggested as a potential pathogen in genitourinary infection... more Haemophilus spp. had been previously suggested as a potential pathogen in genitourinary infections that could be sexually transmitted. In order to check that suggestions we have determined the incidence, pathogenic role, possible sexual transmission and susceptibility to antibiotics in isolates of Haemophilus parainfluenzae and Haemophilus influenzae from genital tract infections. The microbiological samples were taken during a period of four years from patients attended in a Service of Sexual Transmission Diseases and the data were further reviewed. The study included 5,572 genital specimens from 2,182 women prostitutes with different genitourinary infections and from 825 men with urethritis. Microbiological samples were cultured in a non-specific media for genital pathogens and species of Haemophilus spp. and clinical circumstances of isolation were evaluated. Susceptibility tests were performed by using a standard microdilution test. Haemophilus spp. was isolated in 155 samples (...
Se determinó la prevalencia y los factores de riesgo asociados a la violencia contra la mujer en ... more Se determinó la prevalencia y los factores de riesgo asociados a la violencia contra la mujer en una muestra aleatoria estratificada de 1043 estudiantes universitarias españolas (media de edad de 22,2 años). A través de una entrevista realizada por psicólogas se recopiló información demográfica, académica y sobre violencia contra la mujer. La prevalencia de vida de la violencia fue del 15,2%; en el 41,5% de esos casos el maltratador ha sido la pareja, en el 50,9% algún otro hombre y en el 7,6% por ambas fuentes. La prevalencia en último año fue del 7,1%. Los factores de riesgo identificados fueron tener más de 19 años, ingresos familiares anuales superiores a 18.000 �, nivel cultural medio de la familia, residencia familiar urbana y presenciar malos tratos en la infancia o adolescencia. Se concluye que se deberían llevar a cabo campañas de sensibilización para prevenir la violencia contra mujer hacia las estudiantes universitarias y establecer servicios de orientación para aquellas ...
Clínica y Salud
Depression is one of the most common psychiatric disorders among adults and adolescents. Over the... more Depression is one of the most common psychiatric disorders among adults and adolescents. Over the past 12 years, a significant progress in depression prevention research has taking place although many studies in this field still exhibit serious flaws. This paper discusses issues such as the choice of prevention objectives, theoretical considerations, the identification of high-risk groups, and the design of both preventive programs and their evaluation.
Psychological Reports
A 554-member stratified random sample of students at a Spanish university (65.9% women; aged 18-3... more A 554-member stratified random sample of students at a Spanish university (65.9% women; aged 18-34 years) was screened for symptoms of depression using a new Castilian Spanish translation of the Center for Epidemiologic Studies Depression Scale (CES-D) that had been validated by back-translation. Mean CES-D score was 14.2 (SD = 10.3, range 0-54), with a significant difference between the scores of women (M = 15.5; SD = 10.9) and men (M = 11.8; SD = 8.4; t552 = 4.06, p < .0005). Some 33%, of the sample screened positive with the usual CES-D screening threshold of 16, and 16% with the threshold of 24 recommended by Clarke and coworkers. The symptoms most commonly experienced all or most of the time were hopelessness, given the maximum rating by 18.8% of students, difficulty in concentration (17.7%), fatigue (13.9%), inadequacy (13.0%), and disturbance of sleep (12.4%).
Depression is one of the commonest psychological disorders among adolescents and adults. In Spain... more Depression is one of the commonest psychological disorders among adolescents and adults. In Spain it affects more than 3 million patients. There have been significant advances in its diagnosis and treatment, but a problem of this magnitude requires preventive measures. In this communication we review the reasons for prevention and the various approaches that are possible, survey randomized clinical trials of measures aimed at preventing initial onset, analyse the variables governing the efficiency of these trials, and make recommendations for how future research in this field should be carried out. La depresión es uno de los trastornos psicológicos más comunes en la adolescencia y la adultez, afectando a más de 3 millones de personas en España. Aunque se ha hecho un progreso importante en el diagnóstico y en el desarrollo de tratamientos eficaces para la depresión, no es lo suficiente como para afrontar un problema de esta magnitud. Para atajar este problema, la prevención se hace i...
Medicina, 2013
The venous thromboembolic disease (VTD) in adults has a high morbidity and mortality. It can be a... more The venous thromboembolic disease (VTD) in adults has a high morbidity and mortality. It can be also associated to disabling chronic conditions. In spite of this, prophylaxis in healthcare assistance is still underused. In this article, the available evidence in thromboprophylaxis was analyzed to offer recommendations (1) or suggestions (2) classified according to different levels of evidence (A, B or C). Different medical scenarios and types of thromboprophylaxis were analyzed. In major orthopedic surgeries low molecular weight heparins, LMWH, inhibitors of the Xa and IIa factors are recommended (1B) to be started during hospitalization and continued for 35 days in hip replacement surgery and for 10 days in total knee replacement surgery. Knee arthroscopy and spine surgery do not require pharmacologic treatment (2B) unless the patient has other risks factors for thrombosis. In such cases, LMWH are recommended. Non-surgical patients who have at least one risk factor should receive L...
Medicina, 2004
Recurrent aseptic meningitis (RAM) infrequent in elderly patients and generally secondary to drug... more Recurrent aseptic meningitis (RAM) infrequent in elderly patients and generally secondary to drugs. Its association with rheumatologic diseases is also seldom reported in the elderly. Sjögren Syndrome (SS) sometimes affects the central nervous system, but the association between recurrent meningitis and SS is rare, specially in this age-group. We present an 88 year-old auto-valid patient, with a history of xerostomia, xerophthalmia, Raynaud, dysphagia, and recurrent parotid enlargement. In 2001 she developed a lymphocytic meningitis with a complete remission. A year later, she developed again an aseptic lymphocytic meningitis. We ruled out infectious causes. We found a FAN titer 1/160 with a nucleolar-mottled pattern, positive anti Ro and anti RNP antibodies and a positive lupus anticoagulant. We confirmed the ocular dryness and the lip biopsy was compatible with the diagnosis of SS. She had a good outcome with a complete remission without treatment in 10 days. We believe that this ...
International Journal of Environmental Research and Public Health, 2014
The purpose of this study was to identify subgroups of university students with the highest likel... more The purpose of this study was to identify subgroups of university students with the highest likelihood of remaining at elevated levels of depressive symptoms six months following the receipt of a depressive prevention intervention on the basis of known risk factors and participation in one of two depression prevention programs. Data from a randomized controlled trial evaluating depression prevention among 133 college students with elevated depressive symptoms were analyzed. Participants were randomized to a cognitive-behavioral or relaxation training group preventive intervention. Classification tree analysis showed that older age was the strongest risk factor for persistently elevated depression. Additional risk factors were: (1) for younger students, fewer daily pleasant activities; (2) for those with higher level of pleasant activities, higher level of stressful events; and (3) for those with higher level of stressful events, lower assertiveness. Results offer directions for prevention foci, identify specific subgroups of college students to target for depression prevention efforts, and suggest that research aim to help older, non-traditional students or graduating students manage the transition from college to the work force.
Clinical Lymphoma Myeloma and Leukemia, 2012
The venous thromboembolic disease (VTD) in adults has a high morbidity and mortality. It can be a... more The venous thromboembolic disease (VTD) in adults has a high morbidity and mortality. It can be also associated to disabling chronic conditions. In spite of this, prophylaxis in healthcare assistance is still underused. In this article, the available evidence in thromboprophylaxis was analyzed to offer recommendations (1) or suggestions (2) classified according to different levels of evidence (A, B or C). Different medical scenarios and types of thromboprophylaxis were analyzed. In major orthopedic surgeries low molecular weight heparins, LMWH, inhibitors of the Xa and IIa factors are recommended (1B) to be started during hospitalization and continued for 35 days in hip replacement surgery and for 10 days in total knee replacement surgery. Knee arthroscopy and spine surgery do not require pharmacologic treatment (2B) unless the patient has other risks factors for thrombosis. In such cases, LMWH are recommended. Non-surgical patients who have at least one risk factor should receive L...
Resumen El mieloma múltiple (MM) es una enfermedad maligna caracterizada por una proliferación cl... more Resumen El mieloma múltiple (MM) es una enfermedad maligna caracterizada por una proliferación clonal de células plasmáticas atípicas en la médula ósea, que produce una inmunoglobulina (Ig) con estructura homogénea en la sangre y/o en la orina (cadenas livianas). El compromiso del parénquima hepático con masa ocupante en los pacientes con MM es excepcional. Describimos 3 casos clínicos conirmados histológicamente. La ecografía y la tomografía computarizada tienen una sensibilidad intermedia y las imágenes no son patognomónicas, por lo tanto es necesaria la conirmación a través de la biopsia. Se desconoce la implicancia pronóstica de este hallazgo.
Medicina
Resumen El mieloma múltiple (MM) es una enfermedad maligna caracterizada por una proliferación cl... more Resumen El mieloma múltiple (MM) es una enfermedad maligna caracterizada por una proliferación clonal de células plasmáticas atípicas en la médula ósea, que produce una inmunoglobulina (Ig) con estruc- tura homogénea en la sangre y/o en la orina (cadenas livianas). El compromiso del parénquima hepático con masa ocupante en los pacientes con MM es excepcional. Describimos 3 casos clínicos confirmados histológi- camente. La ecografía y la tomografía computarizada tienen una sensibilidad intermedia y las imágenes no son patognomónicas, por lo tanto es necesaria la confirmación a través de la biopsia. Se desconoce la implicancia pronóstica de este hallazgo. Palabras clave: mieloma múltiple, mieloma extramedular, mieloma hepático, compromiso hepático, gammapatía monoclonal Abstract Nodular hepatic lesions secondary to multiple myeloma. Multiple myeloma is characterized by the neoplastic proliferation of a single clone of plasma cells producing a monoclonal immunoglobulin. Myelomatous nod...
Medicina
Resumen La meningitis aséptica recurrente (MAR) en ancianos es rara y generalmente es secundaria ... more Resumen La meningitis aséptica recurrente (MAR) en ancianos es rara y generalmente es secundaria a drogas.
Since the introduction of computed tomography pulmonary angiography, isolated subsegmental pulmon... more Since the introduction of computed tomography pulmonary angiography, isolated subsegmental pulmonary embolism has become a commonly recognized clinical problem, but its clinical relevance remains unclear. The objective of the present study was to evaluate the extent to which the simplified Wells score discriminates between patients with varying levels of risk of complications after presenting with subsegmental pulmonary embolism. Retrospective cohort study. Patients included had subsegmental pulmonary embolism (1 or multiple emboli limited to subsegmental arteries). Primary explanatory variable was the simplified Wells score, categorized as high (&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt;4) or low (≤4). The primary outcome was time to death or new venous thromboembolism. Kaplan-Meier techniques and Cox regression analysis were used to compare the survival experience of patients with high versus low Wells score with and without adjustment for active malignancy, age, Charlson score, previous venous thromboembolism, and previous major surgery in the last 30 days. Seventy-nine patients with subsegmental pulmonary embolism were included. Patients with a high Wells score had a 4-fold increased risk of the composite outcome (hazard ratio = 4.2, 95% confidence interval [CI] = 2.0-8.9, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001). Other covariates significantly associated with increased risk in univariate analyses included active malignancy, a low serum albumin, and an increased Charlson score. In multivariate Cox regression analyses adjusting for these other factors, a high Wells score remained significant (hazard ratio 5.5, 95% CI 2.4-12.6, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; .001). High Wells score is associated with death or new venous thromboembolism during follow-up among patients with subsegmental pulmonary embolism. ClinicalTrials.gov number, NCT01372514.
Journal of Immunoassay and Immunochemistry
A chemiluminescent sandwich ELISA test has been developed for the detection and quantitation of p... more A chemiluminescent sandwich ELISA test has been developed for the detection and quantitation of pneumolysin. The test is based on a mouse monoclonal as the capture antibody and on rabbit polyclonal IgGs as detection antibodies, in combination with an anti-rabbit IgG alkaline phosphatase conjugate. The estimated detection limit of the purified recombinant toxin in phosphate-buffered saline with 0.05% Triton X-100 is around 5 pg ml(-1), with averaged intra- and inter-assay variation coefficients of 7% and 13.5%, respectively. The assay has been applied to the quantitation of pneumolysin in pneumococcal isolates, providing, for the first time, a direct measurement of the amount of the toxin produced by different strains, a variation has been found in their pneumolysin content. The test is highly specific as no other purified toxins or human pneumonia- or meningitis-associated bacteria yielded false-positive results. This specific and highly sensitive method could help in the diagnosis ...
Enfermedades Infecciosas y Microbiología Clínica
The morbidity and mortality rates associated with Streptococcus pneumoniae remain very high world... more The morbidity and mortality rates associated with Streptococcus pneumoniae remain very high worldwide. The virulence of this bacterium is largely dependent on its polysaccharide capsule, which is quite heterogeneous and represents a serious obstacle for designing effective vaccines. However, it has been demonstrated that numerous protein virulence factors are involved in the pathogenesis of pneumococcal disease. An important related finding from experimental animal models is that non-capsulated strains of pneumococci are protective against capsulated ones. Hence, new vaccine designs are focused on the surface proteins (e. g., PspA and PspC) and on the cytolysin, pneumolysin. Moreover, several virulence factors have potential value for pneumococcal diagnosis by urinalysis. In this paper, we review the virulence factors involved in bacteria-host interactions, and the new developments in vaccines and diagnostic methods.
Respiratory research
Intranasal inoculation of Streptococcus pneumoniae D39 serotype 2 causes fatal pneumonia in mice.... more Intranasal inoculation of Streptococcus pneumoniae D39 serotype 2 causes fatal pneumonia in mice. The cytotoxic and inflammatory properties of pneumolysin (PLY) have been implicated in the pathogenesis of pneumococcal pneumonia. To examine the role of PLY in this experimental model we performed ELISA assays for PLY quantification. The distribution patterns of PLY and apoptosis were established by immunohistochemical detection of PLY, caspase-9 activity and TUNEL assay on tissue sections from mice lungs at various times, and the results were quantified with image analysis. Inflammatory and apoptotic cells were also quantified on lung tissue sections from antibody treated mice. In bronchoalveolar lavages (BAL), total PLY was found at sublytic concentrations which were located in alveolar macrophages and leukocytes. The bronchoalveolar epithelium was PLY-positive, while the vascular endothelium was not PLY reactive. The pattern and extension of cellular apoptosis was similar. Anti-PLY ...
Infection and Immunity
We have produced a panel of monoclonal antibodies to pneumolysin, the membrane-damaging toxin fro... more We have produced a panel of monoclonal antibodies to pneumolysin, the membrane-damaging toxin from Streptococcus pneumoniae. We have used these antibodies to identify three regions of the toxin sequence that are involved in the lytic mechanism of this toxin. Two of these sites probably form the cell binding site of this toxin. Antibodies to the third site inhibit the lytic action of this toxin but not the binding of this toxin to cells. This site is engaged in the oligomerization process involved in the formation of pores in cell membranes. Two of these epitopes are also present in the related toxin perfringolysin O.
Clinical Microbiology and Infection
Streptococcus pneumoniae infections are often difficult to diagnose accurately, as it is not unco... more Streptococcus pneumoniae infections are often difficult to diagnose accurately, as it is not uncommon for clinical samples to be culture-negative, particularly after antibiotic administration. The rapid Binax NOW S. pneumoniae urinary antigen test lacks specificity in children, owing to pneumococcal antigen reactions in children who are nasopharyngeal carriers of S. pneumoniae. A western blot assay with a specific polyclonal antibody was developed for direct detection of the putative proteinase maturation protein A (PpmA) in urine samples from children with pneumococcal infections. The sensitivity and specificity of the assay were 66.7% and 100%, respectively. Previous antibiotic treatment or S. pneumoniae nasopharyngeal colonization did not affect PpmA antigenuria. Results also demonstrated the presence of PpmA cross-reactive epitopes in commensal bacteria that co-colonize the nasopharyngeal niche, although the non-pneumococcal cross-reactive protein(s) did not interfere with the d...
Enfermedades Infecciosas y Microbiología Clínica
Haemophilus spp. had been previously suggested as a potential pathogen in genitourinary infection... more Haemophilus spp. had been previously suggested as a potential pathogen in genitourinary infections that could be sexually transmitted. In order to check that suggestions we have determined the incidence, pathogenic role, possible sexual transmission and susceptibility to antibiotics in isolates of Haemophilus parainfluenzae and Haemophilus influenzae from genital tract infections. The microbiological samples were taken during a period of four years from patients attended in a Service of Sexual Transmission Diseases and the data were further reviewed. The study included 5,572 genital specimens from 2,182 women prostitutes with different genitourinary infections and from 825 men with urethritis. Microbiological samples were cultured in a non-specific media for genital pathogens and species of Haemophilus spp. and clinical circumstances of isolation were evaluated. Susceptibility tests were performed by using a standard microdilution test. Haemophilus spp. was isolated in 155 samples (...
Se determinó la prevalencia y los factores de riesgo asociados a la violencia contra la mujer en ... more Se determinó la prevalencia y los factores de riesgo asociados a la violencia contra la mujer en una muestra aleatoria estratificada de 1043 estudiantes universitarias españolas (media de edad de 22,2 años). A través de una entrevista realizada por psicólogas se recopiló información demográfica, académica y sobre violencia contra la mujer. La prevalencia de vida de la violencia fue del 15,2%; en el 41,5% de esos casos el maltratador ha sido la pareja, en el 50,9% algún otro hombre y en el 7,6% por ambas fuentes. La prevalencia en último año fue del 7,1%. Los factores de riesgo identificados fueron tener más de 19 años, ingresos familiares anuales superiores a 18.000 �, nivel cultural medio de la familia, residencia familiar urbana y presenciar malos tratos en la infancia o adolescencia. Se concluye que se deberían llevar a cabo campañas de sensibilización para prevenir la violencia contra mujer hacia las estudiantes universitarias y establecer servicios de orientación para aquellas ...
Clínica y Salud
Depression is one of the most common psychiatric disorders among adults and adolescents. Over the... more Depression is one of the most common psychiatric disorders among adults and adolescents. Over the past 12 years, a significant progress in depression prevention research has taking place although many studies in this field still exhibit serious flaws. This paper discusses issues such as the choice of prevention objectives, theoretical considerations, the identification of high-risk groups, and the design of both preventive programs and their evaluation.
Psychological Reports
A 554-member stratified random sample of students at a Spanish university (65.9% women; aged 18-3... more A 554-member stratified random sample of students at a Spanish university (65.9% women; aged 18-34 years) was screened for symptoms of depression using a new Castilian Spanish translation of the Center for Epidemiologic Studies Depression Scale (CES-D) that had been validated by back-translation. Mean CES-D score was 14.2 (SD = 10.3, range 0-54), with a significant difference between the scores of women (M = 15.5; SD = 10.9) and men (M = 11.8; SD = 8.4; t552 = 4.06, p < .0005). Some 33%, of the sample screened positive with the usual CES-D screening threshold of 16, and 16% with the threshold of 24 recommended by Clarke and coworkers. The symptoms most commonly experienced all or most of the time were hopelessness, given the maximum rating by 18.8% of students, difficulty in concentration (17.7%), fatigue (13.9%), inadequacy (13.0%), and disturbance of sleep (12.4%).
Depression is one of the commonest psychological disorders among adolescents and adults. In Spain... more Depression is one of the commonest psychological disorders among adolescents and adults. In Spain it affects more than 3 million patients. There have been significant advances in its diagnosis and treatment, but a problem of this magnitude requires preventive measures. In this communication we review the reasons for prevention and the various approaches that are possible, survey randomized clinical trials of measures aimed at preventing initial onset, analyse the variables governing the efficiency of these trials, and make recommendations for how future research in this field should be carried out. La depresión es uno de los trastornos psicológicos más comunes en la adolescencia y la adultez, afectando a más de 3 millones de personas en España. Aunque se ha hecho un progreso importante en el diagnóstico y en el desarrollo de tratamientos eficaces para la depresión, no es lo suficiente como para afrontar un problema de esta magnitud. Para atajar este problema, la prevención se hace i...