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1.
Mol Syst Biol ; 19(5): e11294, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-36929731

RESUMEN

Type I interferons (IFN) induce powerful antiviral and innate immune responses via the transcription factor, IFN-stimulated gene factor (ISGF3). However, in some pathological contexts, type I IFNs are responsible for exacerbating inflammation. Here, we show that a high dose of IFN-ß also activates an inflammatory gene expression program in contrast to IFN-λ3, a type III IFN, which elicits only the common antiviral gene program. We show that the inflammatory gene program depends on a second, potentiated phase in ISGF3 activation. Iterating between mathematical modeling and experimental analysis, we show that the ISGF3 activation network may engage a positive feedback loop with its subunits IRF9 and STAT2. This network motif mediates stimulus-specific ISGF3 dynamics that are dependent on ligand, dose, and duration of exposure, and when engaged activates the inflammatory gene expression program. Our results reveal a previously underappreciated dynamical control of the JAK-STAT/IRF signaling network that may produce distinct biological responses and suggest that studies of type I IFN dysregulation, and in turn therapeutic remedies, may focus on feedback regulators within it.


Asunto(s)
Regulación de la Expresión Génica , Factores de Transcripción , Retroalimentación , Antivirales , Transducción de Señal
2.
Vaccine ; 42(7): 1812-1825, 2024 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-38368225

RESUMEN

This report introduces a Brighton Collaboration (BC) case definition for autoimmune hepatitis (AIH), which has been classified as a priority adverse event of special interest (AESI), as there were possible cases seen following COVID-19 vaccination. The case definition was developed by a group of subject matter and BC process experts to facilitate safety data comparability across pre- and post-licensure clinical trials, as well as pharmacovigilance activities in multiple settings with diverse resources and healthcare access. The usual BC case definition development process was followed in an expedited manner, and took two months to complete, including finalising the manuscript for publication, instead of the usual 1 year development time. It includes a systematic review of the literature and an expert consensus to define levels of diagnostic certainty for AIH, and provides specific guidelines for data collection and analysis. Histology, serological and biochemical tests and exclusion of alternate diagnosis were considered necessary to define the levels of certainty (definitive, probable and possible). AEFI reports of suspected AIH were independently classified by the WG members to test its useability and these classifications were used to finalise the case definition. The document underwent peer review by external AIH experts and a Reference Group of vaccine safety stakeholders in high-, low- and middle-income countries to ensure case definition useability, applicability, and scientific integrity. The expedited process can be replicated for development of other standardised case definitions for priority AESIs for endemics and epidemics. While applicable to cases reported following immunisation, the case definition is independent of lapsed time following vaccination and, as such, can also be used to determine background incidence for vaccinated and unvaccinated control groups in studies of causal association. While use of this case definition is also appropriate for the study of safety of other products including drugs, it is not meant to guide clinical case management.


Asunto(s)
Hepatitis Autoinmune , Humanos , Vacunas contra la COVID-19 , Vacunación/efectos adversos , Inmunización/efectos adversos , Recolección de Datos
3.
Lancet ; 379(9816): 617-24, 2012 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-22260988

RESUMEN

BACKGROUND: Effective glycoconjugate vaccines against Neisseria meningitidis serogroups A, C, W-135, and Y have been developed, but serogroup B remains a major cause of severe invasive disease in infants and adolescents worldwide. We assessed immunogenicity and tolerability of a four-component vaccine (4CMenB) in adolescents. METHODS: We did a randomised, observer-blind, placebo-controlled, study at 12 sites in Santiago and Valparaíso, Chile. Adolescents aged 11-17 years received one, two, or three doses of 4CMenB at 1 month, 2 month, or 6 month intervals. Immunogenicity was assessed as serum bactericidal activity using human complement (hSBA) against three reference strains for individual vaccine antigens, and assessed by ELISA against the fourth strain. Local and systemic reactions were recorded 7 days after each vaccination, and adverse events were monitored throughout the study. Participants were initially randomised to five groups (3:3:3:3:1) during the primary phase to receive either one dose, two doses 1 or 2 months apart, or three doses of 4CMenB, or three doses of placebo, with an additional three groups generated for the booster phase. All subjects received at least one dose of 4CMenB. Geometric mean titres, proportions of participants with serum bactericidal antibody titres of 4 or more, and Clopper-Pearson 95% CIs were calculated. The study is registered with ClinicalTrials.gov, number NCT00661713. FINDINGS: Overall, 1631 adolescents (mean age 13·8 [SD 1·9] years) received at least one dose of 4CMenB. After two or three doses, 99-100% of recipients had hSBA titres of 4 or more against test strains, compared with 92-97% after one dose (p<0·0145) and 29-50% after placebo. At 6 months 91-100% of participants still had titres of 4 or more for each strain after two or three doses, but only 73-76% after one dose; seroresponse rates reached 99-100% for each strain after second or third doses at 6 months. Local and systemic reaction rates were similar after each 4CMenB injection and did not increase with subsequent doses, but remained higher than placebo. No vaccine-related serious adverse events were reported and no significant safety signals were identified. INTERPRETATION: On the basis of immunogenicity responses this study provides evidence for an adolescent 4CMenB vaccine schedule of two doses, 1-6 months apart, to provide protection against meningococcal B infection. The extent of this protection against meningococcus B variants circulating worldwide will be determined by national surveys. FUNDING: Novartis Vaccines and Diagnostics.


Asunto(s)
Infecciones Meningocócicas/prevención & control , Vacunas Meningococicas/efectos adversos , Vacunas Meningococicas/inmunología , Neisseria meningitidis Serogrupo B/inmunología , Adolescente , Análisis de Varianza , Niño , Chile , Femenino , Humanos , Masculino , Infecciones Meningocócicas/inmunología , Vacunas Meningococicas/administración & dosificación , Método Simple Ciego , Resultado del Tratamiento , Vacunación/métodos
4.
Bull Environ Contam Toxicol ; 91(5): 539-44, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23995851

RESUMEN

Arsenic release from the abandoned mines and its fate in a local stream were studied. Physicochemical parameters, metals/metalloids and arsenic species were determined. One of the mine drainages was found as a point source of contamination with 309 µg L(-1) of dissolved arsenic; this concentration declined rapidly to 10.5 µg L(-1) about 2 km downstream. Data analysis confirmed that oxidation of As(III) released from the primary sulfide minerals was favored by the increase of pH and oxidation reduction potential; the results obtained in multivariate approach indicated that self-purification of water was due to association of As(V) with secondary solid phase containing Fe, Mn, Ca.


Asunto(s)
Arsénico/análisis , Monitoreo del Ambiente , Minería , Ríos/química , Contaminantes Químicos del Agua/análisis , Sedimentos Geológicos/química , México , Plata
5.
STAR Protoc ; 4(4): 102656, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-37874680

RESUMEN

Muscle stem cells (MuSCs) are the building blocks for regenerating skeletal muscle after trauma. If we intend to maximize the therapeutic potential of MuSCs, we must further study their molecular and functional properties. Here, we present a protocol for the isolation of mouse MuSCs via a two-step enzymatic and mechanical dissociation of skeletal muscle coupled with fluorescence-activated cell sorting (FACS). FACS-isolated MuSCs can be used for various downstream applications including cell culture, cell transduction, immunofluorescence, and gene expression assays. For complete details on the use and execution of this protocol, please refer to Almada et al. (2021).1.


Asunto(s)
Músculo Esquelético , Células Satélite del Músculo Esquelético , Ratones , Animales , Citometría de Flujo/métodos , Células Madre , Técnicas de Cultivo de Célula
6.
Plants (Basel) ; 12(18)2023 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-37765386

RESUMEN

Hexavalent chromium (Cr(VI)) contamination poses serious health and environmental risks. Chromium biosorption has been employed as an effective means of eradicating Cr(VI) contamination. However, research on chromium desorption from chromium-loaded biosorbents is scarce despite its importance in facilitating industrial-scale chromium biosorption. In this study, single- and two-stage chromium desorption from chromium-loaded Cupressus lusitanica bark (CLB) was conducted. Thirty eluent solutions were evaluated first; the highest single-stage chromium desorption efficiencies were achieved when eluent solutions of 0.5 M NaOH, 0.5 M H2SO4, and 0.5 M H2C2O4 were used. Subsequently, two-stage kinetic studies of chromium desorption were performed. The results revealed that using 0.5 M NaOH solution in the first stage and 0.5 M H2C2O4 in the second stage enabled the recovery of almost all the chromium initially bound to CLB (desorption efficiency = 95.9-96.1%) within long (168 h) and short (3 h) desorption periods at each stage. This study clearly demonstrated that the oxidation state of the recovered chromium depends on the chemical nature and concentration of the eluent solution. The results suggest the possible regeneration of chromium-loaded CLB for its subsequent use in other biosorption/desorption cycles.

7.
Chemosphere ; 320: 138081, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36758819

RESUMEN

This work reports a sensitive SERS substrate based on graphene oxide (GO) and quantum-sized ZrO2 nanoparticles (GO/ZrO2) for label-free determination of the organophosphate pesticide methyl parathion (MP). The enhanced light-matter interactions and the consequent SERS effect in these substrates resulted from the effective charge transfer (CT) mechanism attributed to synergistic contributions of three main factors: i) the strong molecular adherence of the MP molecules and the ZrO2 surface which allows the first layer-effect, ii) the relatively abundant surface defects in low dimensional ZrO2 semiconductor NPs, which act as intermediate electronic states that reduce the large bandgap barrier, and iii) the hindered charge recombination derived from the transference of the photoinduced holes to the GO layer. This mechanism allowed an enhancement factor of 8.78 × 104 for GO/ZrO2-based substrates, which is more than 5-fold higher than the enhancement observed for platforms without GO. A detection limit of 0.12 µM was achieved with an outstanding repeatability (variation ≤4.5%) and a linear range up to 10 µM, which is sensitive enough to determine the maximal MP concentration permissible in drinking water according to international regulations. Furthermore, recovery rates between 97.4 and 102.1% were determined in irrigation water runoffs, strawberry and black tea extracts, demonstrating the reliability of the hybrid GO/ZrO2 substrate for the organophosphate pesticides quantification in samples related to agri-food sectors and environmental monitoring.


Asunto(s)
Grafito , Insecticidas , Nanopartículas del Metal , Metil Paratión , Reproducibilidad de los Resultados , Nanopartículas del Metal/química , Grafito/química
8.
Hum Vaccin ; 7(5): 511-22, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21441782

RESUMEN

The safety and immunogenicity of the 10-valent pneumococcal nontypeable Haemophilus influenzae protein D conjugate vaccine (PHiD-CV, Synflorix™) were assessed in 240 healthy Chilean children randomized to receive 3 doses of PHiD-CV (PHiD-CV group) or hepatitis A vaccine (HAV control group) at 2-4-6 months of age. All were offered 1 HAV dose at 12 months (outside study). The PHiD-CV group received a second HAV dose at 18-21 months and PHiD-CV booster at 20-23 months. The HAV control group received 2 PHiD-CV catch-up doses at 18-21 and 20-23 months. Adverse events were recorded and pneumococcal antibody responses and opsonophagocytic activity (OPA) were measured. Both PHiD-CV vaccination schedules were well tolerated and immunogenic against the pneumococcal vaccine serotypes and protein D. The reactogenicity of PHiD-CV primary, booster and catch-up doses was in line with previous PHiD-CV studies, although generally higher than with HAV. For each vaccine serotype, the percentage of subjects with antibody concentrations ≥0.2 µg/ml (GSK's 22F-inhibition ELISA) was at least 93.2% following 3 PHiD-CV primary doses and at least 97.4% post-booster; percentages with OPA titers ≥8 were at least 91.7% post-booster. After 2-dose catch-up, at least 94.3% of children had antibody concentrations ≥0.2 µg/ml against each serotype except 6B (84.3%); at least 95.2% had OPA titers ≥8 except against serotypes 1, 5 and 6B. In conclusion, the safety profiles of 2 PHiD-CV vaccination schedules (3-dose primary plus booster and 2-dose catch-up) were in line with previous studies and PHiD-CV was immunogenic for all 10 vaccine serotypes and protein D.


Asunto(s)
Infecciones por Haemophilus/epidemiología , Infecciones por Haemophilus/prevención & control , Infecciones Neumocócicas/epidemiología , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas/efectos adversos , Vacunas Neumococicas/inmunología , Anticuerpos Antibacterianos/sangre , Preescolar , Chile/epidemiología , Femenino , Humanos , Inmunización Secundaria/métodos , Lactante , Masculino , Vacunas Neumococicas/administración & dosificación , Vacunación/métodos
9.
Front Digit Health ; 3: 615366, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34713093

RESUMEN

Language differences between patients and providers remains a barrier to accessing health care, especially mental health services. One potential solution to reduce inequities for patients that speak different languages and improve their access to care is through the delivery of healthcare through mobile technology. Given that the Latinx community serves as the largest ethnic minority in the United States, this two-phased review examines Spanish app development, feasibility and efficacy. Phase 1 explored the commercial marketplace for apps available in Spanish, while phase 2 involved a literature review of published research centered around the creation, functions, and usability of these apps using the PubMed and Google Scholar electronic databases. Of the apps available on the database, only 14.5% of them had Spanish operability. The literature search uncovered 629 results, of which 12 research articles that tested or described 10 apps met the inclusion criteria. Of the 10 apps studied in this literature review, only four apps were translated to Spanish. Our study reveals that despite increasing interest in Spanish-language apps to address mental health, the commercial marketplace is not currently meeting the demand.

12.
PLoS One ; 13(4): e0196428, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29698442

RESUMEN

The corncob is an agricultural waste generated in huge quantities during corn processing. In this paper, we tested the capacity of corncob particles for water purification by removing the azo dye Direct Yellow 27 (DY27) via biosorption. The biosorption process was investigated in terms of the kinetics, equilibria, and thermodynamics. Batch biosorption studies showed that the biosorption performance has strong inverse correlations to the solution pH and the corncob particle size, and it increases quickly with increasing contact time and initial dye concentration. The pseudo-second-order kinetic model provides the best fit to the experimental data, whereas the Redlich-Peterson isotherm model is most suitable for describing the observed equilibrium biosorption. The biosorption process is exothermic, spontaneous, and physisorption in character. Fourier transform infrared (FTIR) spectroscopy and confocal scanning laser microscopy (CSLM) studies suggest that lignocellulose and proteins play key roles in the biosorption of DY27 from aqueous solutions by corncob. Furthermore, after biosorption onto the corncob, the dye can be effectively desorbed using 0.1 M NaOH solution. Therefore, the corncob can be used as a promising biosorbent to remediate DY27-contaminated water and wastewater.


Asunto(s)
Compuestos Azo/química , Colorantes/química , Naftalenos/química , Purificación del Agua/métodos , Zea mays/química , Adsorción , Compuestos Azo/aislamiento & purificación , Colorantes/aislamiento & purificación , Concentración de Iones de Hidrógeno , Cinética , Microscopía Confocal , Microscopía Electrónica de Rastreo , Modelos Teóricos , Naftalenos/aislamiento & purificación , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier , Termodinámica , Zea mays/metabolismo
13.
J Agric Food Chem ; 54(9): 3440-4, 2006 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-16637705

RESUMEN

The incorporation of Se to fungi has been studied, focusing on element distribution among different cellular compartments and, in particular, polysaccharide structures contained in cell walls. Se-enriched mycelia of Pleurotus ostreatus were obtained in submerged cultures. The incorporation of selenium from the growth medium to mycelia was observed with the relative distribution between cytosol plus cell membranes fraction (CCM) and cell walls fraction (CW) of about 44 and 56%, respectively. CCM fractions were analyzed by size exclusion chromatography with on-line UV (280 nm) and ICP-MS detection (80Se). The results obtained showed selenium binding to components of different molecular masses (about 24% of total selenium coeluted with the compounds of molecular mass > 10 kDa). A polysaccharide-containing fraction of mycelia was treated alternatively with Tris-HCl at pH 7.5 or with chitinase. Better solubility and increased contribution of low molecular mass compounds were observed in chitinase extracts (UV detection), confirming the degradation of polysacharides by the enzyme. The total area under the ICP-MS chromatogram of chitinase extract was 2 times higher with respect to the area for Tris-HCl extract. Furthermore, the relative contribution of selenium in the low molecular mass fraction (molecular mass < 1 kDa) in chitinase extract was 72% as compared to 45% in Tris-HCl extract (based on peak area measurements with respect to total area under the chromatogram). The results obtained suggest selenium binding to chitin-containing polysaccharide structures in fungi cell walls.


Asunto(s)
Membrana Celular/química , Pared Celular/química , Citosol/química , Micelio/ultraestructura , Pleurotus/química , Selenio/análisis , Cromatografía en Gel , Micelio/química
14.
Rev Chilena Infectol ; 33(3): 304-6, 2016 Jun.
Artículo en Español | MEDLINE | ID: mdl-27598280

RESUMEN

Inclusion of the 10-valent pneumococcal conjugated vaccine (PCV10) in the Chilean infant vaccination Program in 2011 was followed by a reduction of hospital admissions and pneumonia-related deaths in this age group. However, a progressive increase of serotype 19A pneumococcal isolates (not included in PCV10) has been observed. According to the analysis of pneumococcal strains performed by the national reference laboratory of the Institute of Public Health as part of a national surveillance on invasive pneumococcal infections, the relative proportion of serotype 19A isolates increased from <5% before 2010 to 12-23% in years 2014-2015. Serotype 19A represented 4-8% of the isolates in the pre-vaccine era among children less than 2 years, increasing to 25% during 2014. This increase has been documented in two-thirds of the national territory. Aimong children <5 years of age, 25% of 19A serotype isolates from non-meningeal infections were penicillin resistant wheras from meningeal infections near 100% were penicillin resistant. Genetic analysis indicates that 48% of these 19A strains belong to clonal complex 320, recognized for its pandemic potential and high antimicrobial resistance. Among children, most invasive infections secondary to serotype 19A have occurred in patients fully vaccinated with PCV10. These epidemiological changes indicate an increase in invasive pneumococcal infections by serotype 19A in Chile and the need to control this problem by changing the current PCV10 for the PCV13 vaccine containing serotype 19A.


Asunto(s)
Comités Consultivos/normas , Infecciones Neumocócicas/prevención & control , Vacunas Neumococicas/uso terapéutico , Streptococcus pneumoniae/clasificación , Vacunación/normas , Niño , Chile , Farmacorresistencia Bacteriana , Humanos , Serogrupo
15.
J Agric Food Chem ; 53(13): 5138-43, 2005 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-15969488

RESUMEN

Huitlacoche is the ethnic name of the young fruiting bodies of Ustilago maydis, a common parasite of maize. In Mexico and other Latin American countries, this fungus has been traditionally appreciated as a local delicacy. In this work a metallomics approach was used with the determination of eight elements in huitlacoche by electrothermal atomic absorption spectrometry as one facet of this approach. The results obtained indicated relatively lower concentrations of commonly analyzed metals, as referred to the data reported for other mushroom types. This effect was ascribed to different accessibilities of elements, depending on fungus substrate (lower from plant than from soil). Subcellular fractionation was accomplished by centrifugation of cell homogenates suspended in Tris-HCl buffer. Recoveries of the fractionation procedure were in the range of 71-103%. For six elements (Cr, Cu, Fe, Mn, Ni, and Pb), the mean relative contributions in cytosol, cell walls, and mixed membrane fraction were 50.7, 48.2, and 1.1% respectively. To attain the molecular weight distribution of compounds containing target elements as an additional aspect of the metallomics approach, the fungus extract (1% sodium dodecyl sulfate in Tris-HCl, 30 mmol L(-)(1), pH 7.0) was analyzed by size exclusion chromatography with UV and ICP-MS detection. With spectrophotometric detection (280 nm), the elution of high molecular weight compounds was observed in the form of one peak (MW > 10 kDa), and several lower peaks appeared at higher retention times (MW < 10 kDa). On ICP-MS chromatograms, a coelution of (59)Co, (63)Cu, (57)Fe, (202)Hg, (60)Ni, and (80)Se with the first peak on the UV chromatogram was clearly observed, indicating that a fraction of each element incorporated with high molecular weight compounds (12.7, 19.8, 33.7, 100, 19.4, and 45.8%, respectively, based on the peak area measurements). From a comparison of (80)Se and (33)S chromatograms (for sulfur analysis, the extract was obtained in the absence of SDS), both elements coeluted with the first UV peak, but their lower molecular weight compounds were apparently different. These findings may contribute to a better understanding of the accumulation of elements in mushrooms.


Asunto(s)
Oligoelementos/análisis , Ustilago/química , Fraccionamiento Celular , Cromatografía en Gel , Espectrometría de Masas , Peso Molecular , Espectrofotometría Atómica , Ustilago/ultraestructura
16.
Biol Trace Elem Res ; 106(3): 265-77, 2005 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16141474

RESUMEN

In this work, the distribution of nine metals in two types of cultivated mushroom had been investigated. For Agaricus bisporus, the biomass was separated into caps and stalks, and for Pleurotus ostreatus, the entire mushrooms were taken for analysis. Electrothermal atomic absorption spectrometry was used for total element determination in acid digests. For accuracy checking, the certified reference material (NIST 1,571, citrus leaves) was analyzed. The results obtained for the two fungi species were within the ranges of concentration reported previously by other authors. Subcellular fractionation was accomplished by centrifugation of cell homogenates, which had been suspended in Tris-HCl buffer. In the first centrifugation (7,300 g, 4 degrees C, 10 min), cell walls were separated (pellet I), and the second centrifugation (147,000g, 4 degrees C, 60 min) yielded mixed membrane fraction (pellet II) and cytosol (supernatant II). Recoveries of the fractionation procedure were in the range 70--100% (with the exception of Fe). For all elements studied, the highest relative contributions were found in cytosol fractions of the fruiting bodies (63--72%, 49--76%, 44--93%, 26--87 pc, 55--85%, 50--68%, 41--78%, 39--78%, 54--67% respectively for Al, Bi, Cd, Cr, Cu, Fe, Mn, Ni, and Pb. Lower contributions were found in cell walls (respectively 22--32%, 24--44%, 6.1--47%, 12--52%, 7.3-- 37%, 7.9--32%, 19--52%, 20--42%, and 25--38%) and only minute amounts in the mixed membrane fraction (3.0--5.8%, 0.7--7.0%, 0.7--8.3%, 1.0--22%, 7.5--14%, 16--24%, 1.1--19%, and 5.1--7.7%). The results obtained indicate that small water-soluble molecules were the primary forms of nine elements in two mushroom species studied. On the other hand, the evidence has been provided on elements binding to larger, water-insoluble molecules contained in the structures of cell wall and membranes. The relative distribution was both element and fungi dependent. Thus, in P. ostreatus, total element levels were higher than in A. bisporus, with the preference for their accumulation in cytosol. On the contrary, total element content in the latter fungi was lower; however, a clear tendency toward more efficient element incorporation to the water-insoluble structures was observed (no apparent differences between stalks and caps).


Asunto(s)
Agaricus/química , Metales/análisis , Pleurotus/química , Metales/química , Solubilidad , Espectrofotometría Atómica
17.
PLoS One ; 10(9): e0137086, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26352933

RESUMEN

The present study investigated the kinetics, equilibrium and thermodynamics of chromium (Cr) ion biosorption from Cr(VI) aqueous solutions by Cupressus lusitanica bark (CLB). CLB total Cr biosorption capacity strongly depended on operating variables such as initial Cr(VI) concentration and contact time: as these variables rose, total Cr biosorption capacity increased significantly. Total Cr biosorption rate also increased with rising solution temperature. The pseudo-second-order model described the total Cr biosorption kinetic data best. Langmuir´s model fitted the experimental equilibrium biosorption data of total Cr best and predicted a maximum total Cr biosorption capacity of 305.4 mg g(-1). Total Cr biosorption by CLB is an endothermic and non-spontaneous process as indicated by the thermodynamic parameters. Results from the present kinetic, equilibrium and thermodynamic studies suggest that CLB biosorbs Cr ions from Cr(VI) aqueous solutions predominantly by a chemical sorption phenomenon. Low cost, availability, renewable nature, and effective total Cr biosorption make CLB a highly attractive and efficient method to remediate Cr(VI)-contaminated water and wastewater.


Asunto(s)
Cromo/química , Cupressus/metabolismo , Contaminantes Químicos del Agua/química , Purificación del Agua , Adsorción , Cromo/toxicidad , Cupressus/química , Cinética , Termodinámica , Aguas Residuales , Agua/química , Contaminantes Químicos del Agua/toxicidad , Contaminación del Agua
18.
Pediatr Infect Dis J ; 21(12): 1115-23, 2002 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-12488660

RESUMEN

BACKGROUND: Nine- and 11-valent pneumococcal conjugate vaccines under development may control pediatric pneumococcal disease in nonindustrialized countries. Because these vaccines are expensive, population-based surveillance of pneumococcal disease in children <36 months of age was undertaken in Santiago, Chile to provide health authorities with reliable data on the burden of invasive pneumococcal disease and causative serotypes, including those in outpatients with high fever. METHODS: Automated blood culture machines were introduced into 9 hospitals that admit 85% of all hospitalized children in Santiago. Acutely ill pediatric febrile ambulatory patients are attended at 8 emergency rooms (ERs) and 36 urgent primary care services. After a 12-month pilot study in 3 ERs, health authorities collected blood cultures from children <36 months of age with high fever seen in the ER as standard practice. isolates were serotyped. RESULTS: Blood cultures of 18 (1.2%) of 1,503 outpatients 6 to 35 months of age with high fever in the pilot study yielded S. In the ensuing 24 months 236 children <36 months old were hospitalized with invasive pneumococcal disease (incidence, 33.9 cases/10(5) children), and 188 bacteremias were detected among ambulatory ER patients with high fever (incidence, 27.0 cases/10(5) children). Although serotypes were similar among hospitalized and ambulatory cases (except 18C, which was more common in the latter), case fatality was 9.5% in hospitalized (21 of 236) 0% in ambulatory cases (0 of 188) (P = <0.0001). High level resistance to penicillin (25.8% vs 10.1%) and cefotaxime (19.5% vs 6.2%) was observed more often among pneumococcal isolates from hospitalized than among ambulatory cases (P < 0.001). CONCLUSIONS: ER surveillance detected approximately one case of pneumococcal bacteremia among febrile ambulatory patients for each hospitalized invasive case. Because 71% of cases were caused by vaccine serotypes (and 87% by vaccine serogroups), 9- and 11-valent pneumococcal conjugate vaccines could prevent most invasive pediatric pneumococcal disease in Chile.


Asunto(s)
Bacteriemia/epidemiología , Infecciones Neumocócicas/epidemiología , Streptococcus pneumoniae/aislamiento & purificación , Distribución por Edad , Atención Ambulatoria , Antibacterianos/administración & dosificación , Bacteriemia/diagnóstico , Bacteriemia/terapia , Preescolar , Chile/epidemiología , Terapia Combinada , Farmacorresistencia Microbiana , Servicio de Urgencia en Hospital , Femenino , Fluidoterapia/métodos , Hospitalización , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Pruebas de Sensibilidad Microbiana , Proyectos Piloto , Infecciones Neumocócicas/diagnóstico , Infecciones Neumocócicas/terapia , Vigilancia de la Población , Probabilidad , Factores de Riesgo , Índice de Severidad de la Enfermedad , Distribución por Sexo , Análisis de Supervivencia , Población Urbana
19.
Hum Vaccin Immunother ; 9(11): 2304-10, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23811804

RESUMEN

We previously demonstrated the immunogenicity and tolerability of the serogroup B meningococcal vaccine, 4CMenB (Bexsero), in 11-17 y-olds randomized to receive 1, 2, or 3 doses at 1, 2, or 6 mo intervals. Participants in this extension study provided an additional blood sample 18-24 mo after last vaccine dose, to assess persistence of serum bactericidal activity with human complement (hSBA), and to compare with age-matched 4CMenB-naïve controls. In the original study, one month after one 4CMenB dose, 93% of subjects had seroprotective hSBA titers (≥4) against indicator serogroup B strains for individual vaccine antigens (fHbp, NadA and NZOMV), increasing to ~100% after two or three doses. After 18-24 mo, 62-73% of subjects given one dose had titers ≥4 against the three antigens, significantly lower rates than after two (77-94%) or three (86-97%) doses. Only proportions with titers ≥ 4 against NZOMV were significantly different between the two (77%) and three (90%, p < 0.0001) dose groups. These results confirm that two doses of 4CMenB, administered 1 to 6 mo apart, provide good levels of bactericidal activity against serogroup B meningococci, which were sustained at least 18-24 mo in over 64% of adolescents for all three tested vaccine-related antigens.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Vacunas Meningococicas/administración & dosificación , Vacunas Meningococicas/inmunología , Neisseria meningitidis/inmunología , Adolescente , Actividad Bactericida de la Sangre , Niño , Proteínas del Sistema Complemento/inmunología , Femenino , Humanos , Masculino , Adulto Joven
20.
Rev Chilena Infectol ; 29(3): 307-11, 2012 Jun.
Artículo en Español | MEDLINE | ID: mdl-23096469

RESUMEN

In Chile, an increased number of notifications of cases of whooping cough was detected at the beginning of October 2010, and maintained through 2012. Accumulated cases during 2011 were 2,581 (15.0 per 100,000), which is greater than the number of cases registered during the period 2008-2010 (2,460 cases). On the other hand, the local sanitary authority introduced a modification of pertussis vaccination schedule (starting 2012), which consists in the replacement of the second booster of pertussis vaccine (DTwP, administered to 4-year-old children) as well as diphtheria-tetanus toxoid (dT, administered to second grade scholars) for an acellular pertussis vaccine with reduced antigenic content (dTpa), which will be administrated to first grade scholars. The Consultive Committee of Immunizations considers that the modification is adequate, since it extends the age of protection, reducing at least in theory the infection in older scholars and adolescents -who are significant sources of transmission of Bordetella pertussis to infants- using an adequate vaccine formulation (acellular pertussis vaccine). The available evidence regarding vaccination in special groups (adolescents and adults, health-care workers and pregnant women) and cocooning strategy are commented.


Asunto(s)
Conferencias de Consenso como Asunto , Vacunas contra Difteria, Tétanos y Tos Ferina Acelular/normas , Vacunación Masiva/métodos , Tos Ferina/prevención & control , Adolescente , Adulto , Preescolar , Chile/epidemiología , Femenino , Humanos , Esquemas de Inmunización , Lactante , Masculino , Evaluación de Resultado en la Atención de Salud , Embarazo , Tos Ferina/epidemiología , Adulto Joven
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