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1.
Eur J Obstet Gynecol Reprod Biol ; 280: 68-72, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36410244

RESUMEN

The aim of this work was to evaluate whether serum cytokines levels are associated with ovarian response in IVF. 149 patients were included in a retrospective study. Cytokines IL-2, IL-4, IL- 6, IL-8, IL-10, VEGF, IFNγ, TNFα, IL-1α, IL-1ß, MCP-1 and EGF were measured by sandwich immunoassay previously to ovarian stimulation. Performing hierarchical cluster analysis, we observed that the antral follicle count, the total oocytes recovered and the MII recovered are grouped in the same cluster as the cytokines IL-2-4-6-10-1α-1ß, IFNγ y TNFα. Then, we found that the ratio between IL and 6 and IL-10 was higher in low responder women (2.15 versus 1.55; p = 0.035). If we establish 0.9 as a cut-off for the IL-6/IL-10, we observed that above this value the risk of having a low response to ovarian stimulation was more than 3 times greater than below this value (22.9 % versus 6.0 %; p = 0.007). Also, the ratio IL-1ß/IL-4 was higher in patients with normal or suboptimal response (0.62 versus 0.34; p = 0.034) and any patient with low response had a value greater than 0.7 (p = 0.003). As a conclusion, the IL-6/IL-10 and IL-1ß/IL-4 ratios showed differences between normoresponder women and patients with low ovarian response.


Asunto(s)
Interleucina-4 , Interleucina-6 , Femenino , Animales , Factor de Necrosis Tumoral alfa , Folículo Ovárico , Interleucina-10 , Estudios Retrospectivos , Interleucina-2 , Fertilización In Vitro , Inducción de la Ovulación , Fertilización
2.
Sci Rep ; 12(1): 6807, 2022 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-35474343

RESUMEN

The factors that cause a preterm birth (PTB) are not completely understood up to date. Moreover, PTB is more common in pregnancies achieved by in-vitro fertilization (IVF) than in spontaneous pregnancies. Our aim was to compare the composition of vaginal microbiome at 12 weeks of gestation between women who conceived naturally or through IVF in order to study whether IVF PTB-risk could be related to vaginal microbiome composition. We performed an observational, prospective and multicentre study among two public hospitals and a fertility private clinic in Spain. Vaginal swabs from 64 pregnant women at 12 weeks of gestation were collected to analyse the microbiome composition by sequencing the V3-V4 region of the 16S rRNA. Our results showed that the vaginal microbiome signature at 12 weeks of pregnancy was different from women who conceived naturally or through IVF. The beta diversity and the genus composition were different between both cohorts. Gardnerella, Neisseria, Prevotella, and Staphylococcus genus were enriched genus in the vaginal microbiome from the IVF group, allowing us to create a balance model to predict both cohorts. Moreover, at species level the L. iners abundance was higher and L. gasseri was lower in the IVF group. As a conclusion, our findings were consistent with a proposed framework in which IVF pregnancy are related to risk for preterm birth (PTB) suggesting vaginal microbiome could be the reason to the relation between IVF pregnancy and risk for PTB.


Asunto(s)
Microbiota , Nacimiento Prematuro , Femenino , Fertilización In Vitro/efectos adversos , Humanos , Recién Nacido , Microbiota/genética , Embarazo , Nacimiento Prematuro/epidemiología , Estudios Prospectivos , ARN Ribosómico 16S/genética
3.
Food Chem ; 381: 132096, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-35094882

RESUMEN

Traditionally, edible flowers have been used as foods and for therapeutic purposes, today they have gained importance due to their bioactive compounds such as flavonols, anthocyanins or other phenolic compounds, which give them potential for biomedical applications. This work evaluated a methanolic extract of Tulbaghia violacea. Eleven individual phenolic compounds were found and quantified by mass spectrometry in the extract. Antioxidant activity tests (TEAC, FRAP and DPPH) and other characterization parameters were assayed (total phenolic content and total flavonoid content). In vitro studies showed antitumoral activity against ovarian tumoral cells mediated by the induction of non-dependent caspase cell death and by the activation of reactive oxygen species. The effect of the extract against features of Alzheimer disease was in vivo assayed in Caenorhabditis elegans. Tulbaghia extract led to a reduction in the 1-42 beta amyloid peptide formation and prevented oxidative stress. These results suggested that Tulbaghia violacea could be a new source of phenolic compounds for nutraceuticals and functional food development.


Asunto(s)
Allium , Antocianinas , Antocianinas/análisis , Antioxidantes/análisis , Antioxidantes/farmacología , Flores/química , Extractos Vegetales/química
4.
Antioxid Redox Signal ; 33(12): 860-881, 2020 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-32064905

RESUMEN

Significance: Cancer is related to redox biology from many points of view, such as initiation and promotion, metabolism and growth, invasion and metastasis, vascularization, or through the interaction with the immune system. In addition, this extremely complex relationship depends on the redox homeostasis of each cellular compartment, which might be used to fight cancer. Recent Advances: New ways of modulating specific and little explored aspects of redox biology have been revealed, as well as new delivery methods or uses of previously known treatments against cancer. Here, we review the latest experimental evidence regarding redox biology in cancer treatment and analyze its potential impact in the development of improved and more effective antineoplastic therapies. Critical Issues: A critical issue that deserves particular attention is the understanding that both extremes of redox biology (i.e., oxidative stress [OS] and reductive stress) might be useful or harmful in relation to cancer prevention and treatment. Future Directions: Additional research is needed to understand how to selectively induce reductive or OS adequately to avoid cancer proliferation or to induce cancer cell death.


Asunto(s)
Productos Biológicos/farmacología , Metales/farmacología , Neoplasias/etiología , Neoplasias/metabolismo , Oxidación-Reducción/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Animales , Cisteína/metabolismo , Glutatión/metabolismo , Homeostasis , Humanos , Mitocondrias/metabolismo , Metástasis de la Neoplasia , Estadificación de Neoplasias , Neoplasias/patología , Neoplasias/terapia , Especies Reactivas de Oxígeno/metabolismo
5.
Waste Manag ; 48: 143-155, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26589869

RESUMEN

Nanomaterials can provide plastics with great advantages on mechanical and active properties (i.e. release and capture of specific substances). Therefore, packaging is expected to become one of the leading applications for these substances by 2020. There are some applications already in the market. Nevertheless, there is still some areas under development. A key issue to be analyzed is the end-of-life of these materials once they become waste, and specifically when nanomaterials are used in biodegradable products. The present study evaluated the disintegration, biodegradability, and ecotoxicity of poly(lactic acid) films reinforced with the three following nanomaterials: (1) montmorillonite modified with an ammonium quaternary salt, (2) calcium carbonate and (3) silicon dioxide. Results on disintegration showed that films completely disintegrated into visually indistinguishable residues after 6-7weeks of incubation in composting environment. Moreover, no differences were observed in the evolution of the bioresidue with respect to color, aspect, and odor in comparison with the control. It was also observed that nanomaterials did not significantly reduce the level of biodegradability of PLA (p>0.05). In fact, biodegradation was higher, without finding significant differences (p>0.05), in all the nano-reinforced samples with respect to PLA after 130days in composting (9.4% in PLA+Nano-SiO2; 34.0% in PLA+Clay1; 48.0% in PLA+Nano-CaCO3). Finally, no significant differences (p>0.05) in ecotoxicity in plants were observed as a result of the incorporation of nanoparticles in the PLA matrix.


Asunto(s)
Ácido Láctico/metabolismo , Nanoestructuras , Polímeros/metabolismo , Suelo , Bentonita/metabolismo , Biodegradación Ambiental , Carbonato de Calcio/metabolismo , Ecotoxicología/métodos , Germinación , Lepidium sativum/crecimiento & desarrollo , Nanoestructuras/química , Poliésteres , Dióxido de Silicio/metabolismo
6.
Waste Manag ; 38: 41-8, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25649917

RESUMEN

The aim of this paper is to analyse the effects of the presence of printed electronics on the paper waste streams and specifically on paper recyclability. The analysis is based on a case study focussed on envelopes for postal and courier services provided with these intelligent systems. The smart printed envelope of the study includes a combination of both conventional (thin flexible batteries and resistors) and printed electronic components (conductive track layout based on nanosilver ink). For this purpose, a comparison between envelopes with and without these components (batteries, resistors and conductive track layouts) was carried out through pilot scale paper recycling tests. The generation of rejects during the recycling process as well as the final quality of the recycled paper (mechanical and optical properties) were tested and quantitatively evaluated. The results show that resistors are retained during the screening process in the sieves and consequently they cannot end up in the final screened pulp. Therefore, mechanical and optical properties of the recycled paper are not affected. Nevertheless, inks from the conductive track layouts and batteries were partially dissolved in the process water. These substances were not totally retained in the sieving systems resulting in slight changes in the optical properties of the final recycled paper (variations are 7.2-7.5% in brightness, 8.5-10.7% in whiteness, 1.2-2.2% in L(∗) values, 3.3-3.5% in opacity and 16.1-27% in yellowness). These variations are not in ranges able to cause problems in current paper recycling processes and restrict the use of recycled paper in current applications. Moreover, real impacts on industrial recycling are expected to be even significantly lower since the proportion of paper product with printed circuits in the current paper waste streams are much lower than the ones tested in this work. However, it should be underlined the fact that this situation may change over the next years due to the future developments in printed electronics and the gradual penetration of these types of devices in the market.


Asunto(s)
Papel , Impresión/métodos , Reciclaje , Administración de Residuos , Electrónica , Proyectos Piloto , Servicios Postales
7.
Waste Manag ; 34(12): 2647-55, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25263216

RESUMEN

Packaging is expected to become the leading application for nano-composites by 2020 due to the great advantages on mechanical and active properties achieved with these substances. As novel materials, and although there are some current applications in the market, there is still unknown areas under development. One key issue to be addressed is to know more about the implications of the nano-composite packaging materials once they become waste. The present study evaluates the extrusion process of four nanomaterials (Layered silicate modified nanoclay (Nanoclay1), Calcium Carbonate (CaCO3), Silver (Ag) and Zinc Oxide (ZnO) as part of different virgin polymer matrices of polyethylene (PE), Polypropylene (PP) and Polyethyleneterephtalate (PET). Thus, the following film plastic materials: (PE-Nanoclay1, PE-CaCO3, PP-Ag, PET-ZnO, PET-Ag, PET-Nanoclay1) have been processed considering different recycling scenarios. Results on recyclability show that for PE and PP, in general terms and except for some minor variations in yellowness index, tensile modulus, tensile strength and tear strength (PE with Nanoclay1, PP with Ag), the introduction of nanomaterial in the recycling streams for plastic films does not affect the final recycled plastic material in terms of mechanical properties and material quality compared to conventional recycled plastic. Regarding PET, results show that the increasing addition of nanomaterial into the recycled PET matrix (especially PET-Ag) could influence important properties of the recycled material, due to a slight degradation of the polymer, such as increasing pinholes, degradation fumes and elongation at break. Moreover, it should be noted that colour deviations were visible in most of the samples (PE, PP and PET) in levels higher than 0.3 units (limit perceivable by the human eye). The acceptance of these changes in the properties of recycled PE, PP and PET will depend on the specific applications considered (e.g. packaging applications are more strict in material quality that urban furniture or construction products).


Asunto(s)
Nanoestructuras/análisis , Embalaje de Productos , Reciclaje/métodos
8.
Microbiology (Reading) ; 157(Pt 1): 189-198, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20929956

RESUMEN

Streptococcus pneumoniae expressing serogroup 6 capsules frequently causes pneumococcal infections and the evolutionary origins of the serogroup 6 strains have been extensively studied. However, these studies were performed when serogroup 6 had only two known members (serotypes 6A and 6B) and before the two new members (serotypes 6C and 6D) expressing wciN(ß) were found. We have therefore reinvestigated the evolutionary origins of serogroup 6 by examining the profiles of the capsule gene loci and the multilocus sequence types (MLSTs) of many serogroup 6 isolates from several continents. We confirmed that there are two classes of cps locus sequences for serogroup 6 isolates. In our study, class 2 cps sequences were limited to a few serotype 6B isolates. Neighbour-joining analysis of cps sequence profiles showed a distinct clade for 6C and moderately distinct clades for class 1 6A and 6B sequences. The serotype 6D cps profile was found within the class 1 6B clade, suggesting that it was created by recombination between 6C and 6B cps loci. Interestingly, all 6C isolates also had a unique wzy allele with a 6 bp deletion. This suggests that serotype switching to 6C involves the transfer of a large (>4 kb) gene segment that includes both the wciN(ß) allele and the 'short' wzy allele. The MLST studies of serotype 6C isolates suggest that the 6C cps locus is incorporated into many different pneumococcal genomic backgrounds but that, interestingly, 6C cps may have preferentially entered strains of the same genomic backgrounds as those of serotype 6A.


Asunto(s)
Cápsulas Bacterianas/genética , Vías Biosintéticas/genética , Streptococcus pneumoniae/genética , Técnicas de Tipificación Bacteriana , Secuencia de Bases , Análisis por Conglomerados , ADN Bacteriano/química , ADN Bacteriano/genética , Evolución Molecular , Orden Génico , Transferencia de Gen Horizontal , Sitios Genéticos , Genotipo , Humanos , Datos de Secuencia Molecular , Tipificación de Secuencias Multilocus , Filogenia , Recombinación Genética , Alineación de Secuencia , Análisis de Secuencia de ADN , Serotipificación , Streptococcus pneumoniae/clasificación
11.
Pediatr Infect Dis J ; 20(10): 959-67, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11642630

RESUMEN

BACKGROUND: Since 1993 the Pan American Health Organization has coordinated a surveillance network with the National Reference Laboratories of Argentina, Brazil, Chile, Colombia, Mexico and Uruguay aimed at monitoring capsular types and antimicrobial susceptibility of Streptococcus pneumoniae causing invasive disease in children <6 years of age. METHODS: The surveillance system included children 6 years of age and younger with invasive disease caused by S. pneumoniae. The identification, capsular typing and susceptibility to penicillin of the isolates were conducted using a common protocol, based on standard methodologies. RESULTS: By June, 1999, 4,105 invasive pneumococcal isolates had been collected mainly from pneumonia (44.1%) and meningitis (41.1%) cases. Thirteen capsular types accounting for 86.1% of the isolates (14, 6A/6B, 5, 1, 23F, 19F, 18C, 19A, 9V, 7F, 3, 9N and 4) remained the most common types during the surveillance period. Diminished susceptibility to penicillin was detected in 28.6% of the isolates, 17.3% with intermediate and 11.3% with high level resistance. Resistance varied among countries and increased during this period in Argentina, Colombia and Uruguay. Serotypes 14 and 23F accounted for 66.6% of the resistance. CONCLUSION: These surveillance data clearly demonstrate the potential impact of the introduction of a conjugate vaccine on pneumococcal disease and the need for more judicious use of antibiotics to slow or reverse the development of antimicrobial resistance.


Asunto(s)
Resistencia a las Penicilinas , Penicilinas/administración & dosificación , Infecciones Neumocócicas/tratamiento farmacológico , Streptococcus pneumoniae/efectos de los fármacos , Niño , Preescolar , Femenino , Humanos , Lactante , Modelos Logísticos , Masculino , México , Penicilinas/uso terapéutico , Vigilancia de la Población , Garantía de la Calidad de Atención de Salud , Control de Calidad , Serotipificación , América del Sur , Streptococcus pneumoniae/clasificación
12.
J Clin Microbiol ; 39(6): 2197-205, 2001 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11376057

RESUMEN

Four hundred ninety-nine methicillin-resistant Staphylococcus aureus (MRSA) isolates recovered from 1996 to 1998 from 22 hospitals in five countries of Latin America-Argentina, Brazil, Chile, Uruguay and Mexico-were examined for antimicrobial susceptibility and clonal type in order to define the endemic clones in those hospitals. The hybridization of ClaI restriction digests with the mecA- and Tn554-specific DNA probes combined with pulsed-field gel electrophoresis of chromosomal SmaI digests (ClaI-mecA::ClaI-Tn554::PFGE clonal types) documented not only the predominance and persistence of the Brazilian clone (XI::B::B) in Brazil (97%) and Argentina (86%) but also its massive dissemination to Uruguay (100%). Moreover, a close relative of the Brazilian clone (XI::kappa::B) was highly represented in Chile (53%) together with a novel clone (47%) (II::E'::F) resistant to pencillin, oxacillin, ciprofloxacin, chloramphenicol, clindamycin, erythromycin, and gentamicin. A unique clonal type (I::NH::M) was detected in Mexico among pediatric isolates and was resistant to penicillin, oxacillin, and gentamicin only. This study clearly documented the very large capacity for geographic expansion and the persistence of the Brazilian clone, contributing not only to the increasing uniformity of the MRSA in South America but worldwide as well.


Asunto(s)
Resistencia a la Meticilina/genética , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Staphylococcus aureus/clasificación , Staphylococcus aureus/efectos de los fármacos , Antibacterianos/farmacología , Elementos Transponibles de ADN/genética , ADN Bacteriano/análisis , Desoxirribonucleasas de Localización Especificada Tipo II/metabolismo , Electroforesis en Gel de Campo Pulsado , Humanos , América Latina/epidemiología , Pruebas de Sensibilidad Microbiana , Hibridación de Ácido Nucleico , Staphylococcus aureus/genética
13.
Microb Drug Resist ; 7(4): 391-401, 2001.
Artículo en Inglés | MEDLINE | ID: mdl-11822779

RESUMEN

The impact of invasive pneumococcal invasive disease is increased by the emergence of antibiotic resistance. We report regional and temporal variations in antibiotic resistance for 4,105 invasive Streptococcus pneumoniae isolates collected from Latin American children <5 years, between 1993 and 1999. Reduced susceptibility to penicillin was detected in 1,182 isolates (28.8%); 36% of these were resistant (> or = 2 microg/ml), including 12.6% with MIC > or = 4 microg/ml, occurring primarily in serotypes 14 and 23F. Reduced susceptibility to third-generation cephalosporins was detected in 12.1% of the collection. Mexico had the highest proportion of reduced susceptibility to penicillin (51.6%) and to third-generation cephalosporins (22%), whereas Brazil had the lowest at 20.9% and 0.7%, respectively. Isolates cultured from patients with pneumonia were more likely to have reduced susceptibility to third-generation cephalosporins than isolates from patients with meningitis (p < 0.0001). Susceptibility to trimethoprim-sulfamethoxazole, chloramphenicol, erythromycin, and vancomycin was tested by disk diffusion for 2.899 isolates. Reduced susceptibility was observed for 45.6%, 11.5%, 6.9%, and 0%, respectively. Thirty-one percent of the strains were resistant to > or = 2 drugs. High levels of antibiotic resistance in Latin America emphasize the need for the development of and adherence to rational antibiotic use guidelines. On-going surveillance will monitor the impact of these programs.


Asunto(s)
Resistencia a Medicamentos , Infecciones Neumocócicas/epidemiología , Infecciones Neumocócicas/metabolismo , Streptococcus pneumoniae/efectos de los fármacos , Factores de Edad , Resistencia a las Cefalosporinas , Niño , Resistencia a Múltiples Medicamentos , Femenino , Hospitales Pediátricos , Humanos , América Latina/epidemiología , Masculino , Pruebas de Sensibilidad Microbiana , Resistencia a las Penicilinas , Infecciones Neumocócicas/tratamiento farmacológico , Control de Calidad , Serotipificación , Resistencia betalactámica
14.
Rev Panam Salud Publica ; 8(3): 185-95, 2000 Sep.
Artículo en Español | MEDLINE | ID: mdl-11036429

RESUMEN

Community-acquired pneumonia is one of the leading causes of infant morbidity and mortality. Studies conducted in developing countries indicate that the most serious symptoms of pneumonia are associated with bacterial causes, mainly Streptococcus pneumoniae, followed by Haemophilus influenzae type b. Managing those infections in children under two years of age is hindered by the lack of appropriate vaccines and by the decreased susceptibility of S. pneumoniae to penicillin and other antibiotics. In 1993, at the initiative of the Regional System for Vaccines of the Pan American Health Organization, and with funding from the Canadian International Development Agency, a study was designed to identify the S. pneumoniae capsular types that cause invasive disease in Latin American children under 5 years of age. The objective of the study was to determine the ideal composition of a conjugate vaccine that could be used in Latin America, and the penicillin susceptibility of the S. pneumoniae isolates. The initiative was undertaken in Argentina, Brazil, Chile, Colombia, Mexico, and Uruguay. This report analyzes the information that the participating countries generated on pneumococcal pneumonia. A total of 3,393 children were found with systemic S. pneumoniae infections, of which 1,578 corresponded to pneumonias. The analysis focused on 1,409 cases of pneumonia in Argentina, Brazil, Colombia, Mexico, and Uruguay. Of the children, 63.8% of them were under two years of age. Twelve prevalent capsular types were identified, of which serotypes 14, 5, and 1 were the three most common in the majority of the countries. At the beginning of the study the highest level of penicillin resistance was found in Mexico (47.0%), and the lowest in Colombia (12.1%). Over the 1993-1998 period, resistance to penicillin increased in the five countries. Penicillin resistance was associated with a small number of capsular serotypes, mainly 14 and 23F. The first of those serotypes was resistant to penicillin and to trimethoprim-sulfamethoxazole, and the second was multiresistant. The frequency of resistance to trimethoprim-sulfamethoxazole was high in all of the countries; Argentina had the highest level, 58.0%. A decrease in susceptibility to chloramphenicol was uncommon, except in Colombia, where there was a resistance level of 23.4%. Resistance to erythromycin was low in all the countries, and all the isolates were susceptible to vancomycin.


Asunto(s)
Neumonía Neumocócica/epidemiología , Preescolar , Humanos , Lactante , América Latina , Pruebas de Sensibilidad Microbiana , Vigilancia de la Población , Serotipificación , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/efectos de los fármacos
15.
Acta Virol ; 44(1): 35-9, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10989690

RESUMEN

In the summer 1999, a measles outbreak occurred in Uruguai. During this outbreak 58 cases were recorded, 36 of which were laboratory confirmed as positive for measles virus (MV) IgM. The cases occurred in touristic places (Montevideo and Maldonado) predominantly among health facilities and tourist service personnel. Urine specimens collected between days 1 and 4 after the onset of the rash from seven cases were analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and nested PCR with primers specific for the carboxyl-terminal region of the nucleoprotein (N) gene. Three of these specimens/cases were positive for MV. Sequencing of 300 nucleotides (nt) of PCR products corresponding to a part of the carboxyl-terminal region of the MV N gene detected in these specimens MV of D6 genotype. The same nucleotide sequences and the same genotype were also previously observed for MV isolates from the 1997 epidemic in Brazil and the 1998 epidemic in Argentina, demonstrating that the D6 genotype was, and may be still circulating in South America.


Asunto(s)
Sarampión/epidemiología , Morbillivirus/aislamiento & purificación , Adulto , Secuencia de Aminoácidos , Anticuerpos Antivirales/sangre , Clonación Molecular , Secuencia de Consenso , Brotes de Enfermedades , Genotipo , Humanos , Inmunoglobulina M/sangre , Sarampión/sangre , Sarampión/virología , Epidemiología Molecular , Datos de Secuencia Molecular , Nucleoproteínas/análisis , Nucleoproteínas/genética , Reacción en Cadena de la Polimerasa , ARN Viral/análisis , Uruguay/epidemiología
16.
Int J Infect Dis ; 4(2): 91-5, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10737845

RESUMEN

OBJECTIVES: Since 1987, the Reference Laboratory of the Ministry of Health of Uruguay has been monitoring infections due to Streptococcus pneumoniae in patients under 5 years of age, in those between 5 to 14 years of age, and in adults. The purpose of the present study was to retrospectively analyze a 10-year collection of invasive S. pneumoniae isolates from children 5 to 14 years of age and adults. METHODS: The Reference Children's Hospital, Pasteur Hospital, and two private hospitals in Montevideo as well as four hospitals located in other representative areas of the country participated in the pneumococcal surveillance program. Based on the information available at the Microbiology Department of the Central Public Health Laboratory (demographic data, date and site of isolate, and clinical diagnosis), all patients with an invasive pneumococcal disease were recorded. Pneumonia was clinically and radiologically diagnosed and etiology was assessed by isolation of S. pneumoniae from blood or pleural fluid. All specimens were collected at the Emergency Service. Capsular serotyping and antimicrobial susceptibilities were determined for each isolate. RESULTS: During the 10-year period, 228 invasive S. pneumoniae were identified and included in the study (blood, n = 129; cerebrospinal fluid [CSF], n = 73; pleural fluid, n = 20; peritoneal fluid, n = 3; synovial fluid, n = 1; pericardic fluid, n = 1; abscess, n = 1). The most frequent clinical presentations were pneumonia (n = 71) and meningitis (n = 69). Thirty-five adults had an underlying condition including, four with malignancies, four with lupus, two with human immunodeficiency virus (HIV)-infected, and two patients in hemodialysis among others. Eighteen of the 228 patients died (7.9% fatality rate), but only four of these had an underlying condition. Eleven fatal cases were attributable to meningitis (2 children, 9 and 11 years old; 9 adults, mean age, 59 y). Four patients with pneumonia and three with sepsis died, including a splenectomized woman. Nine different capsular serotypes (1, 5, 7, 9, 12, 15, 19A, 20, and 23A) were identified among the 18 fatal cases. Resistance to penicillin, generally combined with trimethoprim-sulfamethoxazole, fluctuated annually, not surpassing 10%. CONCLUSIONS: The study results indicated that 96% of the serotypes involved in severe pneumococcal diseases were included in the 23-valent vaccine and that S. pneumoniae resistance to penicillin was moderate.


Asunto(s)
Infecciones Neumocócicas/microbiología , Streptococcus pneumoniae/clasificación , Streptococcus pneumoniae/efectos de los fármacos , Adolescente , Adulto , Anciano , Antibacterianos/farmacología , Técnicas de Tipificación Bacteriana , Niño , Preescolar , Farmacorresistencia Microbiana , Femenino , Humanos , Masculino , Meningitis Neumocócica/epidemiología , Meningitis Neumocócica/microbiología , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Infecciones Neumocócicas/complicaciones , Infecciones Neumocócicas/epidemiología , Neumonía Neumocócica/epidemiología , Neumonía Neumocócica/microbiología , Estudios Retrospectivos , Serotipificación , Streptococcus pneumoniae/aislamiento & purificación , Uruguay/epidemiología
17.
Pediatrics ; 103(2): 409-13, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9925833

RESUMEN

OBJECTIVES: To assess differences in risk factors, clinical presentation, and course of illness between children infected with penicillin-sensitive and drug-resistant Streptococcus pneumoniae (DRSP). DESIGN: A retrospective cohort study conducted in Uruguay and Argentina using information from a hospital-based surveillance system. Hospitalized children 5 years of age and younger who had S pneumoniae isolated from a normally sterile site between June 1993 and October 1996 were eligible. Hospital records were linked with surveillance data. Both stratified univariate analysis and logistic regression was completed. RESULTS: Of the 380 children eligible for the study, 274 records (72%) were available for review. Ninety-nine children (36%) had DRSP; 46 showed intermediate susceptibility (minimum inhibitory concentration, 0.12-1.0 microg/mL) and 53 showed high-level resistance (minimum inhibitory concentration >/=2.0 microg/mL). Children with meningitis were less likely to have DRSP than those with other forms of invasive disease (relative risk = 0. 5; 95% confidence interval [CI], 0.2-0.9). Risk factors associated with DRSP were use of penicillin or ampicillin in the 3 months before illness (odds ratio = 2.9; 95% CI, 1.5-5.7) and possession of private medical coverage (odds ratio = 2.4; 95% CI, 1.2-5.0). Response to therapy, including response to penicillin or ampicillin among children with nonmeningeal invasive disease, course of illness, and clinical outcome did not differ significantly between children infected with penicillin-susceptible or penicillin-resistant isolates. CONCLUSION: In this study, previous use of penicillin or ampicillin and private medical coverage were associated with having DRSP. Children with nonmeningeal invasive disease responded equally well to penicillin regardless of the penicillin susceptibility of their pneumococcal isolate.


Asunto(s)
Resistencia a las Penicilinas , Infecciones Neumocócicas/tratamiento farmacológico , Streptococcus pneumoniae/efectos de los fármacos , Ampicilina/uso terapéutico , Preescolar , Femenino , Humanos , Lactante , Seguro de Salud , Modelos Logísticos , Masculino , Oportunidad Relativa , Penicilinas/uso terapéutico , Estudios Retrospectivos , Factores de Riesgo
18.
Microb Drug Resist ; 4(3): 219-24, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9818973

RESUMEN

Since 1987, Streptococcus pneumoniae (SPN) has been monitored in pediatric and adult populations. In 1994, the SIREVA/PAHO surveillance allowed the assessment of a dramatic increase of penicillin resistance, mainly associated to SPN type 14 also resistance to trimethoprim/sulfamethoxazole. To determine the genetic relatedness of the resistant isolates, analysis of SmaI digests of 61 isolates was performed by pulsed field gel electrophoresis (PFGE). Twelve different profiles were identified. The type 14 resistant SPN (n = 47) displayed a common B pattern, with 15 genetically related subtypes (1-6 bands of difference), with B1 the predominant one (51%). One of the subtypes (B12) was indistinguishable from a French isolate (M13P). This strain represented a South European clone, identified in the late 1980s, that also included serogroup 9 isolates. The type 23F isolates (n = 3) were identical with a representative strain of the well-characterized intercontinental type 23F clone. Neither the type 14 penicillin-susceptible (n = 4) nor the resistant SPN of other serotypes (n = 10) belonged to the B pattern. In summary, the results suggest that the dramatic increase of penicillin resistance in Uruguay depends on the introduction and spread of a type 14 clone, apparently imported from the south of Europe. Follow-up of this phenomenon is mandatory from the point of view of epidemiology and is also a priority for biologic research.


Asunto(s)
Resistencia a las Penicilinas/genética , Streptococcus pneumoniae/efectos de los fármacos , Electroforesis en Gel de Campo Pulsado , Humanos , Pruebas de Sensibilidad Microbiana , Fenotipo , Streptococcus pneumoniae/genética
19.
Clin Infect Dis ; 26(6): 1355-61, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-9636862

RESUMEN

Protein-polysaccharide conjugate vaccines against Streptococcus pneumoniae promise to be an effective public health intervention for children, especially in an era of increasing antimicrobial resistance. To characterize the distribution of capsular types in Latin America, surveillance for invasive pneumococcal infection in children < or = 5 years of age was done in six countries between February 1993 and April 1996. Fifty percent of 1,649 sterile-site isolates were from children with pneumonia, and 52% were isolated from blood. The 15 most common of the capsular types prevalent throughout the region accounted for 87.7% of all isolates. Overall, 24.9% of isolates had diminished susceptibility to penicillin: 16.7% had intermediate resistance and 8.3% had high-level resistance. Three customized vaccine formulas containing 7, 12, and 15 capsular types were found to have regional coverages of 72%, 85%, and 88%, respectively. This study emphasizes the need for local surveillance for invasive pneumococcal disease prior to the development and evaluation of protein-polysaccharide conjugate vaccines for children.


Asunto(s)
Infecciones Neumocócicas/epidemiología , Vacunas Bacterianas/uso terapéutico , Preescolar , Humanos , Lactante , América Latina/epidemiología , Resistencia a las Penicilinas , Penicilinas/uso terapéutico , Infecciones Neumocócicas/tratamiento farmacológico , Infecciones Neumocócicas/prevención & control
20.
Braz J Infect Dis ; 2(3): 128-134, 1998 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-11103000

RESUMEN

HIV-infected children are more likely than other children to develop pneumonia, which in these children is often recurrent or persistent. The main reservoir of the major pathogens is the nasopharynx, but to date no data has been published on the frequency and biologic characteristics of S.pneumoniae, H.influenzae and respiratory viruses found in the upper respiratory tract of children born to human immunodeficiency virus-infected mothers. To document these aspects, 105 children was monitored by pharyngeal swab (PS) and nasopahryngeal aspirates (NPA) who attended an outpatient clinic for HIV-infection evaluation. Bacterial identification was performed by standard procedures. Serotype, biotype and beta-lactamase production was investigated in H.influenzae isolates. S.pneumoniae serotypes were recognized by "quellung" and the susceptibility to 4 antibiotics was assessed. Respiratory syncytial viruses, parainfluenza, influenza A and B, and adenoviruses were diagnosed by indirect immunofluorescence and/or viral isolation in cell cultures. Twenty-nine children were identified as infected by HIV as a result of maternal-child transmission. Seventy children born to HIV-positive mothers but who were not HIV-infected served as controls. Of 269 PS, 110 110 S. pneumoniae and 92 H.influenzae were identified. Also 31 viruses were detected in 188 NPA. After stratifying by age no differences were observed in the frequency of bacterial colonization or in the presence of viruses in the upper respiratory tract of the two groups. Some biologic characteristics of the agents were noteworthy such as the frequency of colonization by S.pneumoniae serotype 14, the predominance of H.influenzae biotype I and the high frequency of viruses in NPA of asymptomatic children. Of note, although colonization frequencies were similar, children presenting with acute respiratory illness (ARI) were more likely to have bacteria isolated if they also had HIV-infection than if they were HIV-negative. It is concluded that HIV-infection in infants as a result of maternal virus transmission have a similar frequency of bacteria and virus colonization of their respiratory tract, but a higher frequency of ARI and perhaps a higher frequency of types of bacteria with special characteristics.

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