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Recurrent positivity in a patient with COVID-19 may be due to various reasons, not necessarily reinfection. There is concern about the occurrence frequency of reinfection. Five databases and a preprint/preprint repository were searched. All case reports, case series, and observational studies were included. Bias was assessed for each study with the Newcastle-Ottawa Scale tool and reported according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA-2020). After eligibility, 77 studies were included for qualitative synthesis (52 case reports, 21 case series, and four case-controls; 1131 patients included). Of these, 16 studies described a second contact with the SARS-CoV-2 positive case, five studies described healthcare profession-related infection, ten studies described that the source of reinfection was likely to be from the community, one study described travel-related infection, nine studies described vulnerability-related infection due to comorbidity. The mean number of days from discharge or negative test to reinfection ranged from 23.3 to 57.6 days across the different included studies. The risk of bias for all case report/series studies was moderate/high. For observational studies, the risk of bias was low. Reinfection of patients with COVID-19 occurs between the first and second month after the first infection, but beyond, and 90 days have been proposed as a point to begin to consider it. The main factor for reinfection is contact with COVID-19 positive cases.
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INTRODUCTION: Due to its high transmissibility, measures aimed at reducing the spread of SARS CoV2 have become mandatory. Different organizations have recommended performing polymerase chain reaction tests (PCR) as part of the preoperative screening of surgical patients. We aimed to determine the performance of PCR testing to detect asymptomatic carriers. METHODS: Observational study carried out at a tertiary care center. We compared the results of preoperative real-time reverse-transcription-PCR test (RT-PCR) performed on a cohort of patients pending surgery with the results we would have expected assuming the epidemiological data released by government offices. RESULTS: We registered no positives in the 2,722 preoperative RT-PCR tests performed in our health care area between epidemiological Weeks 18 to 21, meaning a cumulative incidence trending to zero. Assuming public epidemiological data, the probabilistic projection of potential asymptomatic individuals ranged from 0.27 × 10e-4 (according to official data of new cases diagnosed by PCR) to 4.69 × 10e-4 if we assumed cases confirmed by IgG test in our province. Assuming a RT-PCR sensitivity of 95%, to obtain a positive result we should perform 38,461 and 2,028 tests respectively. CONCLUSIONS: In scenarios of very low prevalence and despite high sensitivity scores, indiscriminate preoperative RT-PCR screening is of a questionable effectiveness for detecting asymptomatic carriers. Our findings evidence the difficulty of establishing reliable predictive models for the episodic and rapidly evolving incidence of infections such as has characterized the SARS CoV2 pandemic.
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Prueba de Ácido Nucleico para COVID-19 , COVID-19/diagnóstico , Portador Sano/diagnóstico , Pandemias , Cuidados Preoperatorios , SARS-CoV-2 , COVID-19/epidemiología , Prueba de Ácido Nucleico para COVID-19/estadística & datos numéricos , Portador Sano/epidemiología , Humanos , Incidencia , Prevalencia , Estudios Retrospectivos , España/epidemiologíaRESUMEN
Pt-S and Pt-N interactions resulting from the coordination of cisplatin, oxaliplatin and carboplatin to two synthetic peptides that differ from each other in one amino acid (Met or His) have been thoroughly studied in this work. The degree of Pt-binding was determined by inductively coupled plasma mass spectrometry after the separation of the Pt-complexes from the unreacted drugs by size exclusion chromatography. Cisplatin and oxaliplatin showed high affinity for the peptides from the first hours of incubation, although the peptides required longer incubation times to obtain the same platination degrees with cisplatin than with oxaliplatin. Once the reactions reached their maximum binding degrees, the complexes with oxaliplatin began to dissociate, revealing binding reversibility, while a pseudo steady-state was observed for cisplatin until the last day of incubation. Conversely, the equilibrium was not reached for carboplatin and the His-peptide after 30â¯days, showing a binding degree of 16%, versus 78% for the Met-peptide. The S-donor group also presented an important influence on the reactivity and the adduct formation. The reaction rate for the Met-peptide was faster than the hydrolysis of oxaliplatin and carboplatin, and all the drugs, except oxaliplatin, were able to coordinate up to 3 different donor groups, which were identified by nanospray mass spectrometry. Since structural characterization of metal-complexes often represents an analytical challenge during electrophoretic separations, the strength of Pt-Met and Pt-His bonds was also evaluated under these conditions. The nature of the electrophoretic agents and the incubation times used were the parameters that most affected the stability. Higher Pt losses were found for the Met-peptide (35-90%) than for the His-peptide (16-48%), indicating that Pt-Met bonds were kinetically preferred while Pt-His interactions were thermodynamically favored.
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Antineoplásicos/química , Carboplatino/química , Cisplatino/química , Histidina/química , Metionina/química , Oxaliplatino/química , Péptidos/química , Secuencia de Aminoácidos , Sitios de Unión , Estabilidad de Medicamentos , Cinética , Espectrometría de MasasRESUMEN
Composite material (AC-ZnO) was prepared by growing ZnO nanoparticles during the production of biomass based-activated carbon (AC) via the incorporation of zinc acetate in the process. Comprehensive analyses confirmed the presence of ZnO nanoparticles over the AC surface and described the particular nature of the composite adsorbent. Methylene blue (MB) equilibrium data fitted the Dubinin-Radushkevich model. The MB adsorption capacity was higher for the bare activated carbons (197.9-188.7 mg/g) than the activated carbons with ZnO nanoparticles (137.6-149.7 mg/g). The adsorption of the MB on the adsorbents is physical because the mean adsorption energy (E) is between 1.76 and 2.00 kJ/mol. Experiments that combine adsorption and photocatalysis were carried out with different loads of adsorbents and with and without UV-light exposure. Photocatalytic activity was identified mostly at the first stage of the adsorption process and, in the case of experiments with less load of the composite AC-ZnO, because the light obstruction effect of the activated carbon is more for higher loads. The ZnO grown over AC improves the adsorption of cations such as Pb, Al and Fe in aqueous phase (polluted river water) and provides antibacterial capacity against Escherichia coli and Salmonella typhimurium.
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Antibacterianos/farmacología , Escherichia coli/efectos de los fármacos , Nanopartículas del Metal/análisis , Salmonella typhimurium/efectos de los fármacos , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/química , Óxido de Zinc/análisis , Adsorción , Biomasa , Carbón Orgánico/análisis , FotólisisRESUMEN
Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) has been revealed as a convenient technique for trace elemental imaging in tissue sections, providing elemental 2D distribution at a quantitative level. For quantification purposes, in the last years several approaches have been proposed in the literature such as the use of CRMs or matrix matched standards. The use of Isotope Dilution (ID) for quantification by LA-ICP-MS has been also described, being mainly useful for bulk analysis but not feasible for spatial measurements so far. In this work, a quantification method based on ID analysis was developed by printing isotope-enriched inks onto kidney slices from rats treated with antitumoral Pt-based drugs using a commercial ink-jet device, in order to perform an elemental quantification in different areas from bio-images. For the ID experiments 194Pt enriched platinum was used. The methodology was validated by deposition of natural Pt standard droplets with a known amount of Pt onto the surface of a control tissue, where could be quantified even 50pg of Pt, with recoveries higher than 90%. The amount of Pt present in the whole kidney slices was quantified for cisplatin, carboplatin and oxaliplatin-treated rats. The results obtained were in accordance with those previously reported. The amount of Pt distributed between the medullar and cortical areas was also quantified, observing different behavior for the three drugs.
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Espectrometría de Masas , Imagen Molecular , Platino (Metal)/metabolismo , Animales , Riñón/metabolismo , Ratas , Reproducibilidad de los ResultadosRESUMEN
This paper studies the use of two activated carbon samples made of cocoa pod husk (CPH-AC) and one commercial activated carbon sample in the adsorption of As(V), Cd(II) and Pb(II) from multicomponent synthetic solutions and from the Puyango-Tumbes River water, a river located in northwest Peru. The characterization of the activated carbon samples was conducted. The CPH-AC samples exhibited a specific surface area (SBET) between 709 and 1117 m2/g and a pH point of zero charge (pHPZC) between 4.4 ± 0.2 and 5 ± 0.2, while the commercial material gave an SBET value of 775 m2/g and a pHPZC value of 7.6 ± 0.1. All the evaluated samples displayed the capacity to adsorb As(V), Cd(II) and Pb(II) from both aqueous systems. The adsorption efficiency for Pb was outstanding reaching the value of 89%. A pseudo-second order kinetic model was satisfactorily applied for most of the activated carbon samples.
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Arsénico/química , Cadmio/química , Carbón Orgánico/química , Plomo/química , Contaminantes Químicos del Agua/química , Adsorción , Cacao/química , Concentración de Iones de Hidrógeno , Ríos/químicaRESUMEN
In this study, a chicken meat containing AgNPs (candidate reference material Nanolyse 14) has been used as a model matrix to study the fate and behaviour of AgNPs upon oral ingestion following an in vitro model that included saliva, gastric and intestinal digestions. The behaviour of a 40nm AgNPs standard solution during the three digestion steps was also evaluated. Sample preparation conditions were optimised to prevent AgNPs oxidation and/or aggregation and to ensure the representativeness of the reported results. Total silver released from the test sample and the evaluated AgNP standard was determined by inductively coupled plasma mass spectrometry (ICPMS). The presence of both AgNPs and dissolved silver in the extracts was confirmed by single particle (SP)-ICPMS analysis. AgNPs were sized and the particle number concentration determined in the three digestion juices. Experimental results demonstrated differentiated behaviours for AgNP from the standard solution and the meat sample highlighting the relevance of using physiological conditions for accurate risk assessment. In the most realistic scenario assayed (i.e., spiked chicken meat analysis), only 13% of the AgNPs present in the reference material would reach the intestine wall. Meanwhile, other bioaccessible dissolved forms of silver would account for as much as 44% of the silver initially spiked to the meat paste.
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Digestión/efectos de los fármacos , Contaminación de Alimentos/análisis , Tracto Gastrointestinal/efectos de los fármacos , Nanopartículas del Metal/química , Productos Avícolas/análisis , Plata/química , Animales , Pollos , Tracto Gastrointestinal/metabolismo , Humanos , Espectrometría de Masas , Tamaño de la PartículaRESUMEN
BACKGROUND: The present study aims to analyze diagnostic concordance between the DSM-IV and the DSM-5 for posttraumatic stress disorder (PTSD) diagnostic criteria and their different groups of symptoms. Furthermore, analyses are conducted to establish the features of participants with no concordant diagnoses. METHOD: The study assessed 166 people over 18 who had experienced at least one traumatic event. PTSD diagnosis was established using the Global Scale for Posttraumatic Stress (EGEP), a self-report measure to assess PTSD. RESULTS: The presence of cognitive avoidance was a determinant in the PTSD DSM-5 diagnosis (86% positive predictive value). The analysis of the non-concordant individuals revealed that individuals who were diagnosed according to the DSM-IV criteria but not the DSM-5 criteria were primarily indirect victims. Conversely, individuals who were diagnosed with the DSM-5 criteria and not with the DSM-IV criteria presented cognitive avoidance and alterations in cognition not included in the DSM-IV criteria. CONCLUSIONS: A within-subjects concordance analysis showed high agreement for PTSD diagnosis between the two classifications. Differences between the diagnoses are due to the new definition of C (avoidance) and D (negative alterations in cognitions and mood) in the DSM-5.
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Manual Diagnóstico y Estadístico de los Trastornos Mentales , Trastornos por Estrés Postraumático/diagnóstico , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Silver migration from a commercial baby feeding bottle and a food box containing AgNPs, as confirmed by SEM-EDX analysis, was evaluated using food simulant solutions [i.e., water, 3% (v/v) acetic acid, and 10% and 90% (v/v) ethanol]. Silver release was investigated at temperatures in the 20-70°C range using contact times of up to 10 days. Migration of silver from the food box was in all cases 2 to 3 orders of magnitude higher than that observed for the baby bottle, although the total silver content in the original box material was half of that found in the baby bottle. As expected, for both food containers, silver migration depended on both the nature of the tested solution and the applied conditions. The highest release was observed for 3% acetic acid at 70°C for 2h, corresponding to 62ngdm(2) and 1887ngdm(-2) of silver for the baby bottle and the food box, respectively. Single particle-inductively coupled plasma mass spectrometry (SP-ICPMS) was used to characterise and quantify AgNPs in the food simulants extracts. Sample preparation was optimized to preserve AgNPs integrity. The experimental parameters affecting AgNPs detection, sizing and quantification by SP-ICPMS were also optimised. Analyses of water and acidic extracts revealed the presence of both dissolved silver and AgNPs. Small AgNPs (in the 18-30nm range) and particle number concentrations within the 4-1510 10(6)L(-1) range were detected, corresponding to only 0.1-8.6% of the total silver released from these materials. The only exception was AgNPs migrated into water at 40°C and 70°C from the food box, which accounted for as much as 34% and 69% of the total silver content, respectively.
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Embalaje de Alimentos/métodos , Espectrometría de Masas/métodos , Nanopartículas del Metal/química , Plásticos/química , Plata/análisis , Ácido Acético/química , Contaminación de Alimentos/análisis , Humanos , Nanopartículas del Metal/ultraestructura , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Reproducibilidad de los Resultados , Plata/química , Temperatura , Factores de Tiempo , Agua/químicaRESUMEN
Canine norovirus (NoV) and astrovirus (AstV) were studied in 20 domestic sewage samples collected in two cities in Uruguay. Four samples were characterized as canine AstV after phylogenetic analysis clustering with strains detected in Italy and Brazil in 2008 and 2012, respectively. One sample was characterized as canine NoV and clustered with a strain detected in Hong Kong and recently classified as GVII. This study shows the occurrence of a canine NoV GVII strain for the first time in the American continent and also warns about possible zoonotic infection, since canine strains were detected in domestic sewage.
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Infecciones por Astroviridae/veterinaria , Infecciones por Caliciviridae/veterinaria , Enfermedades de los Perros/virología , Mamastrovirus/aislamiento & purificación , Norovirus/aislamiento & purificación , Aguas del Alcantarillado/virología , Animales , Infecciones por Astroviridae/virología , Infecciones por Caliciviridae/virología , Perros , Mamastrovirus/genética , Datos de Secuencia Molecular , Norovirus/genética , Filogenia , UruguayRESUMEN
AIMS: The aim of this study was to investigate the presence of the recently identified human astrovirus (HAstV) and to increase the knowledge of the molecular epidemiology of classical HAstV detected in Uruguay. METHODS AND RESULTS: Recently identified and classical HAstV genotypes were investigated by RT-PCR targeting the ORF1b and ORF2 genome regions in 20 samples obtained between September 2011 and April 2013 in two cities of the eastern region of Uruguay. Four of 20 samples (20%) were identified as MLB-1 genotype and it was found a new MLB-1 classification through the segregation of the worldwide reported MLB-1 strains in two genetic lineages proposed and named: MLB-1a and MLB-1b. Fourteen (70%) samples were positive for classical HAstV and 12 of them were successfully sequenced and genotyped as: HAstV-1 (n = 10), HAstV-2 and HAstV-5 (one sample each). CONCLUSION: These results constitute the first report in the Latin American region concerning the molecular detection and characterization of MLB-1 HAstV strains in environmental samples. SIGNIFICANCE AND IMPACT OF THE STUDY: This study highlights the benefits of an environmental surveillance to study emerging enteric viruses circulating in human societies.
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Infecciones por Astroviridae/virología , Mamastrovirus/aislamiento & purificación , Aguas del Alcantarillado/virología , Secuencia de Bases , Monitoreo del Ambiente , Gastroenteritis/virología , Genotipo , Humanos , Mamastrovirus/clasificación , Mamastrovirus/genética , Epidemiología Molecular , Datos de Secuencia Molecular , Filogenia , Uruguay/epidemiologíaRESUMEN
The aim of this study was to determine the molecular epidemiology of classical human astrovirus (HAstV) strains in sewage samples from four Uruguayan cities: Bella Unión, Salto, Paysandú, and Fray Bentos, located in the Northwestern region of the country. Overall, 96 sewage samples were collected biweekly between March 2011 and February 2012 and were subject to ultracentrifugation methodology in order to concentrate the viruses. RT-PCR directed to the ORF2 genome region was performed followed by sequencing and phylogenetic analysis. Forty-three (45 %) out of 96 analyzed samples were positive for HAstV (Mamastrovirus 1) and 31 of them were successfully sequenced being 21 (49 %) of them classified as HAstV-1 genotype (1a lineage) and 10 (23 %) as HAstV-2 genotype (eight strains belonging to the 2d lineage and two strains to the 2c lineage). The 1a lineage circulated throughout the year, while the 2d lineage only in the coldest months (June to October). Strikingly, the 2c lineage was detected only in Salto city during March 2011. In this city it was observed the highest frequency of HAstV and the greatest genetic diversity, probably due to its role as high touristic spot with an important influx of visitants from others regions of Uruguay and also from other countries. This study constitutes the first report in Uruguay that describes the phylogenetic diversity and genotype distribution of HAstV strains circulating in the Northwestern region evidencing a high frequency and also the presence of several different lineages.
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This study evaluated the feasibility of asymmetric flow field flow fractionation coupled with inductively coupled plasma mass spectrometry (AF4-ICP-MS) for separation, characterization and quantification of silver nanoparticles (AgNPs) in complex nutraceutical and beverage samples. For improved determination, different analysis conditions were proposed depending on the NP size, i.e. below 20 nm and in the 20-60 nm range. After optimization of the different experimental parameters affecting the AF4 separation process and the analyte detection, the proposed methods showed a wide dynamic linear range (i.e., in the 10-1000 µg L(-1)) and limits of detection below 28 ng L(-1). A previous probe ultrasonication for 90 s (corresponding to 45 pulses of 2 s) of the tested samples resulted in complete AgNPs disaggregation. As a result, a fast accurate determination was achieved (complete analysis was done in ca. 37 min). The practicality of the proposed methodology for the intended determination was demonstrated by successful determination of the AgNPs present in a variety of nutraceuticals and a beverage at concentration levels in the 0.7-29.5×10(3) µg L(-1) range. A good agreement was observed among these concentration data and those determined by more conventional sample preparation techniques, such as ultracentrifugation and acid digestion. Also, the estimated NP sizes using AF4 compared satisfactorily with those determined by image techniques, i.e. transmission electron microscopy (TEM). All together demonstrated the utility of this novel analytical methodology for the analysis of AgNPs of different size in complex matrices.
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Bebidas/análisis , Suplementos Dietéticos/análisis , Fraccionamiento de Campo-Flujo/métodos , Espectrometría de Masas/métodos , Nanopartículas del Metal/química , Plata/química , Nanopartículas del Metal/ultraestructura , Microscopía Electrónica de Transmisión , Tamaño de la PartículaRESUMEN
In this work, a methodology based on a reducing IEF separation in combination with a FASP tryptic digestion able to maintain the integrity of cisplatin-protein complexes has been developed. The method is based on OFFGEL-IEF under conditions provided by the thiol-free reducing agent TBP, which allowed the separation of cisplatin-binding proteins in liquid fractions. The FASP procedure is applied as an intermediate stage between the IEF separation and MS analysis where the proteins are retained and concentrated in a commercially available ultrafiltration device. The filter unit acts as a proteomic reactor for detergent removal, buffer exchange, chemical modification (reduction and alkylation) and protein digestion. Finally, purified peptides are recovered by centrifugation. This procedure provides efficiencies comparable to standard in-solution digestion and the risk of platinum-complexes loss is minimized due to the fact that reagents employed along the process are subsequently eliminated before the following step. The stability of platinum-protein complexes under the FASP tryptic digestion, either using TBP or DTT as reducing agents, was maintained, allowing the identification of several platinum-containing peptides from cisplatin-HSA. This methodology was applied to the separation of platinum-enriched protein fractions obtained by SEC-ICP-MS in a kidney tissue extract from a rat treated with cisplatin, followed by further identification by nLC-ESI-LTQ-MS/MS after FASP tryptic digestion of selected platinum-containing liquid fractions.
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Antineoplásicos/metabolismo , Cromatografía en Gel/métodos , Cisplatino/metabolismo , Riñón/metabolismo , Proteínas/metabolismo , Espectrometría de Masas en Tándem/métodos , Animales , Antineoplásicos/aislamiento & purificación , Cisplatino/aislamiento & purificación , Humanos , Unión Proteica , Proteínas/aislamiento & purificación , RatasRESUMEN
The analysis of the complexes between metal-based chemotherapeutic drugs and proteins in biological samples, such as cisplatin or oxaliplatin, can be a challenge due to metal strong reactivity towards S-donor molecules such as dithiothreitol (DTT) or ß-mercaptoethanol (BME), usually employed as reducing agents in electrophoretic separations and proteolytic digestions for LC-MS/MS analysis.â¢This protocol describes the use of the thiol-free reducing trialkylphosphines, such as tributylphosphine (TBP) and tris(2-carboxyethyl)phosphine (TCEP) as suitable reagents for the preservation of the metal-protein complexes during OFFGEL-IEF and SDS-PAGE separations, respectively.â¢Moreover, the filter-aided sample preparation (FASP) method is presented as an advantageous option to perform tryptic in-solution digestions of metal-protein complexes in combination with OFFGEL-IEF separations.â¢The FASP procedure allows including previous reduction and alkylation steps in addition to proteolysis, ensuring the preservation of the metal-protein complexes. The limited time that proteins remain in contact with the reducing agent, either TBP or even DTT, during FASP could be a key factor for its extraordinary performance on the digestion of metal-protein complexes.
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In this work, the reactivity of the citostatic drugs such as oxaliplatin, cisplatin and carboplatin towards proteins and the stability of Pt-protein complexes along their storage were evaluated. Neither native-PAGE nor nrSDS-PAGE seems to be suitable for the separation of carboplatin-binding proteins. A reducing electrophoretic separation procedure able to maintain the integrity of oxaliplatin-protein complexes has been developed. The method is based on SDS-PAGE under conditions provided by the thiol-free reducing agent tris (2-carboxyethyl) phosphine (TCEP), which allowed the separation of oxaliplatin-binding proteins in narrow bands with almost quantitative recoveries. Different amounts of platinum-bound protein bands covering the range 0.3-2.0 µg were excised and mineralised for platinum determination, showing good linearity. Limits of detection for a mixture of five standard proteins (transferrin, albumin, carbonic anhydrase, myoglobin and cytochrome c) incubated with oxaliplatin were within the range 11.0-44.0 pg of platinum, which were satisfactory for their application to biological samples. The suitability of the TCEP-based SDS-PAGE for the separation of platinum-enriched protein fractions of a kidney cytosol from a rat treated with oxaliplatin was demonstrated. The identification of high Pt to protein ratio cytosolic fractions was carried out by separating the cytosolic platinum-binding proteins by SEC-ICP-MS. Several cytosolic renal proteins were identified in those gel bands containing platinum-enriched protein fractions using nLC-ESI-LTQ-MS/MS after in-gel digested with trypsin. In addition, fractions containing platinum-enriched proteins with lower theorical molecular weight were directly analysed by nLC-ESI-LTQ-MS/MS after in-solution tryptic digestion allowing protein identification.
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Carboplatino/química , Cisplatino/química , Compuestos Organoplatinos/química , Fragmentos de Péptidos/análisis , Fosfinas/química , Platino (Metal)/análisis , Animales , Anhidrasas Carbónicas/química , Cisplatino/administración & dosificación , Citocromos c/química , Electroforesis en Gel de Poliacrilamida , Riñón/química , Riñón/efectos de los fármacos , Límite de Detección , Mioglobina/química , Oxaliplatino , Unión Proteica , Proteolisis , Ratas , Albúmina Sérica/química , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrometría de Masas en Tándem , Transferrina/química , Tripsina/químicaRESUMEN
Group A rotaviruses (RV-A) are the leading cause of viral gastroenteritis in children worldwide and genotype G9P[8] is one of the five most common genotypes detected in humans. In order to gain insight into the degree of genetic variability of G9P[8] strains circulating in Cameroon, stool samples were collected during the 1999-2000 rotavirus season in two different geographic regions in Cameroon (Southwest and Western Regions). By RT-PCR, 15 G9P[8] strains (15/89=16.8%) were identified whose genomic configurations was subsequently determined by complete or partial gene sequencing. In general, all Cameroonian G9 strains clustered into current globally-spread sublineages of the VP7 gene and displayed 86.6-100% nucleotide identity amongst themselves and 81.2-99.5% nucleotide identity with global G9 strains. The full genome classification of all Cameroonian strains was G9-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1 but phylogenetic analysis of each gene revealed that the strains were spread across 4 or more distinct lineages. An unusual strain, RVA/Human-wt/CMR/6788/1999/G9P[8], which shared the genomic constellation of other Cameroonian G9P[8] strains, contained a novel G9 subtype which diverged significantly (18.8% nucleotide and 19% amino acid distance) from previously described G9 strains. Nucleotide and amino acid alignments revealed that the 3' end of this gene is highly divergent from other G9 VP7 genes suggesting that it arose through extensive accumulation of point mutations. The results of this study demonstrate that diverse G9 strains circulated in Cameroon during 1999-2000.
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Infecciones por Rotavirus/virología , Rotavirus/clasificación , Rotavirus/genética , Secuencia de Aminoácidos , Antígenos Virales/genética , Camerún , Proteínas de la Cápside/genética , Preescolar , Genoma Viral , Humanos , Lactante , Datos de Secuencia Molecular , Filogenia , Alineación de SecuenciaRESUMEN
Among non-cancer effects of arsenic, cardiovascular diseases have been well documented; however, few are known about the arsenic fate in cardiovascular tissues. We studied the analytic bioinorganic arsenic behaviour in cardiovascular tissues from an arsenic exposure coronary heart disease patient group from Antofagasta-Chile against a small unexposed arsenic coronary heart patient group. Total arsenic concentrations were measured in pieces of cardiovascular tissues of the arsenic-exposed and unexposed coronary heart patient groups by hydride generation atomic absorption spectrometry (HG-AAS); speciation analysis was made by high performance liquid chromatography-inductively coupled plasma-mass spectrometry (HPLC-ICP-MS). Pieces of auricle (AU), mammary artery (MAM), saphenous vein (SAP) and fat residuals (FAT) were considered in this study. The arsenic concentrations in AU and MAM tissues were significantly different between both groups of patients. Also, it was demonstrated that the AU is an 'As(3+) target tissue.' Otherwise, linking of the total concentrations of arsenic with conditional variables and variables related to medical geology factors allowed us to infer that the latter are more important for the cardiovascular risk of arsenic exposure in the Antofagasta region. Knowledge of total arsenic and the prevalence of the trivalent ion (As(3+)) in the AU of patients could contribute to understanding the effect of arsenic on cardiovascular diseases.
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Arsénico/toxicidad , Enfermedades Cardiovasculares/inducido químicamente , Sistema Cardiovascular/metabolismo , Exposición a Riesgos Ambientales/efectos adversos , Contaminantes Químicos del Agua/toxicidad , Adulto , Anciano , Arsénico/aislamiento & purificación , Arsénico/farmacocinética , Enfermedades Cardiovasculares/epidemiología , Enfermedades Cardiovasculares/metabolismo , Chile/epidemiología , Cromatografía Líquida de Alta Presión , Exposición a Riesgos Ambientales/análisis , Humanos , Persona de Mediana Edad , Espectrofotometría Atómica , Contaminantes Químicos del Agua/aislamiento & purificación , Contaminantes Químicos del Agua/farmacocinéticaRESUMEN
Group A rotaviruses (RV-A) are the major cause of gastroenteritis in infants and young children around the world. Each year RV-A causes approximately 11 million episodes of severe diarrhea, with an estimated of 611,000 deaths. Epidemiologic surveys have identified P[8]G1, P[4]G2, P[8]G3, P[8]G4, and P[8]G9 as the most common global genotypes associated with diarrhea in children up to 5-year old. Surveillance studies and documentation of RV-A G and P genotypes is necessary for a comprehensive evaluation of the evolution of new strains, and assessing the capability of vaccines to provide heterotypic protection. It is known that reassortments are the driving force for genetic diversity through sudden changes in RV-A genome. In this study, we identified two unusual P/G combinations, P[8]G8 and P[4]G8, occurring in Rio de Janeiro during 2002. Results obtained in this study suggest that P[8]G8 RV-A strain originated from a reassortment event that occurred between RV-A P[4]G8 and P[8]G9 strains circulating in Rio de Janeiro in the same year. G8 strains identified in this study, as well as G8 strains detected in Recife by Montenegro et al. [Montenegro et al. (2007) J Med Virol 79: 335-340], showed a close genetic relationship with strains from Africa, where this genotype have become prevalent.
Asunto(s)
Diarrea/epidemiología , Virus Reordenados/aislamiento & purificación , Infecciones por Rotavirus/epidemiología , Rotavirus/aislamiento & purificación , Brasil/epidemiología , Diarrea/virología , Humanos , Epidemiología Molecular , Filogenia , ARN Viral/genética , Virus Reordenados/clasificación , Virus Reordenados/genética , Rotavirus/clasificación , Rotavirus/genética , Infecciones por Rotavirus/virología , Población UrbanaRESUMEN
OBJECTIVE: To compare the experience and attitude of obstetricians in Europe towards late termination of pregnancy and the factors affecting their responses. DESIGN: Cluster sampling cross-sectional survey. All neonatal intensive care unit (NICU)-associated maternity units were recruited (census sampling) in Luxembourg, the Netherlands and Sweden. In France, Germany, Italy, Spain and the UK, units were selected at random. In every recruited unit, all obstetricians with at least 6 months' experience were invited to participate. SETTING: NICU-associated maternity units in eight European countries. POPULATION: Obstetricians with at least 6 months' clinical experience. METHODS: An anonymous, self-administered questionnaire was used. Multinomial logistic analysis was used to identify factors predicting the obstetricians' views about modifying the law governing late termination in their country. MAIN OUTCOME MEASURE: Obstetricians' experience of late termination of pregnancy and views about national policies. RESULTS: One hundred and five units and 1530 obstetricians participated (response rates 70 and 77% respectively). The most common indications for late termination were congenital anomalies and women's physical health. Feticide was not common except in France, Luxembourg and the UK. Active euthanasia of a liveborn was practiced in France and the Netherlands. Obstetricians in Germany were more likely to feel that late termination should be more severely restricted, the opposite was true in Spain and the Netherlands. In Italy, there was dissatisfaction with current status, but opinion was divided, reflecting views on both sides of the debate. CONCLUSIONS: This research outlines current practice in a difficult and sensitive area and suggests the need for more discussion and support for all those who were involved.