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1.
J Dairy Sci ; 107(8): 5393-5401, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38608944

RESUMEN

The diffusion of microplastics in the food supply chain is prompting public concern as their impact on human health is still largely unknown. The aim of this study was to qualitatively and quantitatively characterize microplastics in skim-milk powder samples (n = 16) from different European countries (n = 8) through Fourier-transform infrared microspectroscopy in attenuated total reflectance mode analysis. The present study highlights that the use of hot alkaline digestion has enabled the efficacious identification of microplastics in skim-milk powders used for cheesemaking across European countries. The adopted protocol allowed detection of 29 different types of polymeric matrices for a total of 536 plastic particles. The most abundant microplastics were polypropylene, polyethylene, polystyrene, and polyethylene terephthalate. Microplastics were found in skim-milk powders in 3 different shapes (fiber, sphere, and irregular fragments) and 6 different colors (black, blue, brown, fuchsia, green, and gray). Results demonstrate the presence of microplastics in all skim-milk powder samples, suggesting a general contamination. Results of the present study will help to evaluate the impact of microplastics intake on human health.


Asunto(s)
Microplásticos , Leche , Leche/química , Microplásticos/análisis , Animales , Polvos , Humanos , Espectroscopía Infrarroja por Transformada de Fourier
2.
Nature ; 546(7657): 280-284, 2017 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-28593963

RESUMEN

The discovery of new materials is hampered by the lack of efficient approaches to the exploration of both the large number of possible elemental compositions for such materials, and of the candidate structures at each composition. For example, the discovery of inorganic extended solid structures has relied on knowledge of crystal chemistry coupled with time-consuming materials synthesis with systematically varied elemental ratios. Computational methods have been developed to guide synthesis by predicting structures at specific compositions and predicting compositions for known crystal structures, with notable successes. However, the challenge of finding qualitatively new, experimentally realizable compounds, with crystal structures where the unit cell and the atom positions within it differ from known structures, remains for compositionally complex systems. Many valuable properties arise from substitution into known crystal structures, but materials discovery using this approach alone risks both missing best-in-class performance and attempting design with incomplete knowledge. Here we report the experimental discovery of two structure types by computational identification of the region of a complex inorganic phase field that contains them. This is achieved by computing probe structures that capture the chemical and structural diversity of the system and whose energies can be ranked against combinations of currently known materials. Subsequent experimental exploration of the lowest-energy regions of the computed phase diagram affords two materials with previously unreported crystal structures featuring unusual structural motifs. This approach will accelerate the systematic discovery of new materials in complex compositional spaces by efficiently guiding synthesis and enhancing the predictive power of the computational tools through expansion of the knowledge base underpinning them.

3.
Philos Trans A Math Phys Eng Sci ; 380(2224): 20210160, 2022 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-35400193

RESUMEN

The spread of COVID-19 has been thwarted in most countries through non-pharmaceutical interventions. In particular, the most effective measures in this direction have been the stay-at-home and closure strategies of businesses and schools. However, population-wide lockdowns are far from being optimal, carrying heavy economic consequences. Therefore, there is nowadays a strong interest in designing more efficient restrictions. In this work, starting from a recent kinetic-type model which takes into account the heterogeneity described by the social contact of individuals, we analyse the effects of introducing an optimal control strategy into the system, to limit selectively the mean number of contacts and reduce consequently the number of infected cases. Thanks to a data-driven approach, we show that this new mathematical model permits us to assess the effects of the social limitations. Finally, using the model introduced here and starting from the available data, we show the effectiveness of the proposed selective measures to dampen the epidemic trends. This article is part of the theme issue 'Kinetic exchange models of societies and economies'.


Asunto(s)
COVID-19 , Control de Enfermedades Transmisibles , COVID-19/epidemiología , Humanos , Cinética , Modelos Teóricos , SARS-CoV-2
4.
J Math Biol ; 83(1): 4, 2021 06 26.
Artículo en Inglés | MEDLINE | ID: mdl-34173890

RESUMEN

We introduce a mathematical description of the impact of the number of daily contacts in the spread of infectious diseases by integrating an epidemiological dynamics with a kinetic modeling of population-based contacts. The kinetic description leads to study the evolution over time of Boltzmann-type equations describing the number densities of social contacts of susceptible, infected and recovered individuals, whose proportions are driven by a classical SIR-type compartmental model in epidemiology. Explicit calculations show that the spread of the disease is closely related to moments of the contact distribution. Furthermore, the kinetic model allows to clarify how a selective control can be assumed to achieve a minimal lockdown strategy by only reducing individuals undergoing a very large number of daily contacts. We conduct numerical simulations which confirm the ability of the model to describe different phenomena characteristic of the rapid spread of an epidemic. Motivated by the COVID-19 pandemic, a last part is dedicated to fit numerical solutions of the proposed model with infection data coming from different European countries.


Asunto(s)
COVID-19 , Modelos Teóricos , Pandemias , Control de Enfermedades Transmisibles , Humanos , Cinética
5.
Ecotoxicol Environ Saf ; 123: 81-8, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26232851

RESUMEN

Potential environmental impacts of engineered nanoparticles (ENPs) can be understood taking into consideration phytotoxicity. We reported on the effects of ionic (FeCl3), micro- and nano-sized zerovalent iron (nZVI) about the development of three macrophytes: Lepidium sativum, Sinapis alba and Sorghum saccharatum. Four toxicity indicators (seed germination, seedling elongation, germination index and biomass) were assessed following exposure to each iron concentration interval: 1.29-1570mg/L (FeCl3), 1.71-10.78mg/L (micro-sized iron) and 4.81-33,560mg/L (nano-iron). Exposure effects were also observed by optical and transmission electron microscopy. Results showed that no significant phytotoxicity effects could be detected for both micro- and nano-sized zerovalent irons, including field nanoremediation concentrations. Biostimulation effects such as an increased seedling length and biomass production were detected at the highest exposure concentrations. Ionic iron showed slight toxicity effects only at 1570mg/L and, therefore, no median effect concentrations were determined. By microscopy, ENPs were not found in palisade cells or xylem. Apparently, aggregates of nZVI were found inside S. alba and S. saccharatum, although false positives during sample preparation cannot be excluded. Macroscopically, black spots and coatings were detected on roots of all species especially at the most concentrated treatments.


Asunto(s)
Cloruros/toxicidad , Compuestos Férricos/toxicidad , Lepidium sativum/efectos de los fármacos , Sinapis/efectos de los fármacos , Sorghum/efectos de los fármacos , Fenómenos Químicos , Cloruros/química , Compuestos Férricos/química , Germinación/efectos de los fármacos , Lepidium sativum/crecimiento & desarrollo , Nanopartículas/química , Nanopartículas/toxicidad , Raíces de Plantas/efectos de los fármacos , Plantones/crecimiento & desarrollo , Sinapis/crecimiento & desarrollo , Sorghum/crecimiento & desarrollo
6.
Medicina (B Aires) ; 76(6): 369-372, 2016.
Artículo en Español | MEDLINE | ID: mdl-27959846

RESUMEN

Sickle cell syndrome HbS/ß thalassemia is an inheritable mendelian type disease where two affected alleles are simultaneously present, one from HbS (ßS) and the other from ß thalassemia. That situation is mainly linked to individuals who share African and Mediterranean ancestors. The mutation responsible for HbS is a point mutation, whereas for ß thalassemia, there are more than 200 mutations that cause different degrees of deficiency synthesis of ß globin chain, which justifies the clinical and genetic heterogeneity of this syndrome. It is presented a clinical case of a young adult man with limited resources that consulted by longstanding bone pain. The patient presented anemia with a marked microcytosis. Hemoglobin electrophoresis was performed, an abnormal peak in position of HbS and high HbA2 fraction were detected. These last results indicated two possible molecular alterations simultaneously, for this reason the molecular study was performed looking for the most common ß thalassemia mutations in our population and, the point mutation responsible for S hemoglobinopathy. Clinical data and biochemical laboratory allowed the diagnosis of sickle cell syndrome. The molecular study confirmed the syndrome carrying mutations IVS-I nt 110 G > A, responsible for ß thalassemia and, codon 6 A > T (GAG → GTG: Glu → Val) responsible for S hemoglobinophaty. Since it is a disease of high health impact, it is important to provide genetic counseling to the whole family.


Asunto(s)
Anemia de Células Falciformes/genética , Hemoglobina Falciforme/genética , Mutación Puntual , Talasemia beta/genética , Adulto , Anemia de Células Falciformes/diagnóstico , Biomarcadores , Electroforesis Capilar , Humanos , Masculino , Biología Molecular , Reacción en Cadena de la Polimerasa , Síndrome , Talasemia beta/diagnóstico
7.
Meat Sci ; 217: 109626, 2024 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-39137452

RESUMEN

The diffusion of microplastics in meat products is an emerging topic, as their impact on animal and human health is still largely unknown. The present study aimed to preliminarily determine the number and the quality of microplastics diffusion in beef hamburgers (n = 10) through Fourier-transformed infrared micro-spectroscopy in attenuated total reflectance mode analysis. Microplastics were detected in all analyzed samples. The abundance of microplastics ranged from 200.00 to 30,300.00 MP/kg. Microplastics observed in the analyzed samples were mainly characterized by irregular shapes (95.99%), grey color (70.16%), and dimensions comprised between 51 and 100 µm (57.46%). Eighteen different polymers were detected, with polycarbonate (30,300.00 MP/kg), polyethylene (1580.00 MP/kg) and polypropylene (750.00 MP/kg) being the most abundant classes. Results demonstrate an extensive diffusion of microplastics in the analyzed samples, which may be originated from various sources, including animal body, industrial processing, and packaging. Findings from this study will aid in pinpointing the source of microplastics contamination, enabling the creation of targeted guidelines to mitigate microplastics spread in processed meat food.


Asunto(s)
Contaminación de Alimentos , Microplásticos , Animales , Bovinos , Microplásticos/análisis , Contaminación de Alimentos/análisis , Espectroscopía Infrarroja por Transformada de Fourier , Carne Roja/análisis , Embalaje de Alimentos/métodos , Productos de la Carne/análisis
8.
J Hosp Infect ; 151: 21-28, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-38945400

RESUMEN

BACKGROUND: Continuous fluid infusions delivered between therapies by piggy-back systems avoid disconnection and reconnection of central venous catheters (CVCs), thereby reducing opportunities for line contamination. However, the impact of continuous versus intermittent infusions on central line-associated bloodstream infections (CLABSIs) is unknown. AIM: To investigate the effect of temporary infusion interruption and line disconnection, with or without use of a 70% isopropyl alcohol cap (IPA-C) on CLABSI rates in haematology patients. METHODS: Quasi-experimental study in two haemato-oncology units. At baseline (P1, September 2020 to August 2021), continuous intravenous piggy-back infusions were mandatory. In a first intervention phase (P2, September 2021 to August 2022), infusion disconnections were implemented with use of a 70% isopropyl alcohol cap (IPA-C) for passive decontamination. In a second intervention phase (P3, September 2022 to August 2023), infusion disconnections continued without the use of IPA-C. Rates of CLABSI were compared across the three intervention periods using segmented Poisson regression. FINDINGS: A total of 11,039 catheter-days across 764 CVCs and 16,226 patient-days were included. Twenty-one CLABSIs were recorded across all intervention periods. Compared with P1, incidence rate ratios (IRRs) for CLABSI did not significantly change in P2 (IRR 0.76 (95% CI 0.27-2.15)) and P3 (IRR 0.79 (95% CI 0.28-2.22)). No CVCs were removed due to occlusion during the study period. Five of 21 CLABSIs were polymicrobial, and coagulase-negative staphylococci were isolated in 19/21 cases (90%). CONCLUSION: Interruption of continuous infusions in haemato-oncology patients with a CVC was not associated with a substantial change in CLABSI rates, whether or not an IPA-C was used.


Asunto(s)
Infecciones Relacionadas con Catéteres , Humanos , Infecciones Relacionadas con Catéteres/epidemiología , Infecciones Relacionadas con Catéteres/prevención & control , Infusiones Intravenosas , Femenino , Masculino , Persona de Mediana Edad , Neoplasias Hematológicas/complicaciones , Cateterismo Venoso Central/efectos adversos , Anciano , Catéteres Venosos Centrales/efectos adversos , Ensayos Clínicos Controlados no Aleatorios como Asunto , Sepsis/etiología , Sepsis/epidemiología
9.
Artículo en Inglés | MEDLINE | ID: mdl-36213149

RESUMEN

Fake news spreading, with the aim of manipulating individuals' perceptions of facts, is now recognized as a major problem in many democratic societies. Yet, to date, little has been understood about how fake news spreads on social networks, what the influence of the education level of individuals is, when fake news is effective in influencing public opinion, and what interventions might be successful in mitigating their effect. In this paper, starting from the recently introduced kinetic multi-agent model with competence by the first two authors, we propose to derive reduced-order models through the notion of social closure in the mean-field approximation that has its roots in the classical hydrodynamic closure of kinetic theory. This approach allows to obtain simplified models in which the competence and learning of the agents maintain their role in the dynamics and, at the same time, the structure of such models is more suitable to be interfaced with data-driven applications. Examples of different Twitter-based test cases are described and discussed.

10.
Catal Letters ; : 1-12, 2022 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-36320430

RESUMEN

Here we report some results on a 3 steps benzene caprolactam process via amination, aniline Hydroxymation and Beckmann rearrangement. The amination proceeds with hydroxylamine trifluoroacetate, with 97% of conversion and selectivity of 90%, catalyzed by V compounds. We achieve 98% of conversion and 95% of selectivity in the hydroxymation of aniline in the presence of hydroxylamine trifluoroacetate, sulfonic resin and Pd/C. While in the absence of the resin, hydrogenation of hydroxylamine trifluoroacetate occurs readily to the ammonium salt. The reaction occurs likely by the exchanged hydroxylamine and the aniline reduction intermediate. The use of hydroxylamine trifluoroacetate, instead of the chloride, favors the sustainability of the process by avoiding the ammonium chloride formation. The absence of salt except those derived from the trifluoroacetic acid allows a complete reuse of the trifluoroacetic acid and the only byproduct is ammonium nitrate obtained by resin regeneration. Beckmann rearrangement of the so produced cyclohexanone oxime occurs easily after diethyl ether evaporation and additions of a solution trifluoroacetic acid acetonitrile in high yield and selectivity. Graphical Abstract: New three steps caprolactam process via benzene amination and aniline hydrogenation. Supplementary Information: The online version contains supplementary material available at 10.1007/s10562-022-04207-9.

11.
Clin Microbiol Infect ; 27(2): 182-191, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32120036

RESUMEN

BACKGROUND: Rapid diagnostic tests (RDTs) for infectious diseases, with a turnaround time of less than 2 hours, are promising tools that could improve patient care, antimicrobial stewardship and infection prevention in the emergency department (ED) setting. Numerous RDTs have been developed, although not necessarily for the ED environment. Their successful implementation in the ED relies on their performance and impact on patient management. OBJECTIVES: The aim of this narrative review was to provide an overview of currently available RDTs for infectious diseases in the ED. SOURCES: PubMed was searched through August 2019 for available studies on RDTs for infectious diseases. Inclusion criteria included: commercial tests approved by the US Food and Drug Administration (FDA) or Conformité Européenne (CE) in vitro diagnostic devices with data on clinical samples, ability to run on fully automated systems and result delivery within 2 hours. CONTENT: A nonexhaustive list of representative commercially available FDA- or CE-approved assays was categorized by clinical syndrome: pharyngitis and upper respiratory tract infection, lower respiratory tract infection, gastrointestinal infection, meningitis and encephalitis, fever in returning travellers and sexually transmitted infection, including HIV. The performance of tests was described on the basis of clinical validation studies. Further, their impact on clinical outcomes and anti-infective use was discussed with a focus on ED-based studies. IMPLICATIONS: Clinicians should be familiar with the distinctive features of each RDT and individual performance characteristics for each target. Their integration into ED work flow should be preplanned considering local constraints of given settings. Additional clinical studies are needed to further evaluate their clinical effectiveness and cost-effectiveness.


Asunto(s)
Enfermedades Transmisibles/diagnóstico , Pruebas Diagnósticas de Rutina/instrumentación , Pruebas Diagnósticas de Rutina/métodos , Automatización de Laboratorios , Enfermedades Transmisibles/tratamiento farmacológico , Enfermedades Transmisibles/etiología , Aprobación de Pruebas de Diagnóstico , Servicio de Urgencia en Hospital , Europa (Continente) , Humanos , Juego de Reactivos para Diagnóstico , Estados Unidos , United States Food and Drug Administration
12.
Microbiome ; 9(1): 28, 2021 01 24.
Artículo en Inglés | MEDLINE | ID: mdl-33487167

RESUMEN

BACKGROUND: Viral infections are common complications following allogeneic hematopoietic stem cell transplantation (allo-HSCT). Allo-HSCT recipients with steroid-refractory/dependent graft-versus-host disease (GvHD) are highly immunosuppressed and are more vulnerable to infections with weakly pathogenic or commensal viruses. Here, twenty-five adult allo-HSCT recipients from 2016 to 2019 with acute or chronic steroid-refractory/dependent GvHD were enrolled in a prospective cohort at Geneva University Hospitals. We performed metagenomics next-generation sequencing (mNGS) analysis using a validated pipeline and de novo analysis on pooled routine plasma samples collected throughout the period of intensive steroid treatment or second-line GvHD therapy to identify weakly pathogenic, commensal, and unexpected viruses. RESULTS: Median duration of intensive immunosuppression was 5.1 months (IQR 5.5). GvHD-related mortality rate was 36%. mNGS analysis detected viral nucleotide sequences in 24/25 patients. Sequences of ≥ 3 distinct viruses were detected in 16/25 patients; Anelloviridae (24/25) and human pegivirus-1 (9/25) were the most prevalent. In 7 patients with fatal outcomes, viral sequences not assessed by routine investigations were identified with mNGS and confirmed by RT-PCR. These cases included Usutu virus (1), rubella virus (1 vaccine strain and 1 wild-type), novel human astrovirus (HAstV) MLB2 (1), classic HAstV (1), human polyomavirus 6 and 7 (2), cutavirus (1), and bufavirus (1). CONCLUSIONS: Clinically unrecognized viral infections were identified in 28% of highly immunocompromised allo-HSCT recipients with steroid-refractory/dependent GvHD in consecutive samples. These identified viruses have all been previously described in humans, but have poorly understood clinical significance. Rubella virus identification raises the possibility of re-emergence from past infections or vaccinations, or re-infection. Video abstract.


Asunto(s)
Enfermedad Injerto contra Huésped/sangre , Enfermedad Injerto contra Huésped/virología , Secuenciación de Nucleótidos de Alto Rendimiento , Metagenómica , Esteroides , Adulto , Anciano , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Esteroides/efectos adversos , Esteroides/uso terapéutico , Adulto Joven
13.
Obes Surg ; 19(3): 339-44, 2009 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19083071

RESUMEN

BACKGROUND: Obesity is associated with cardiovascular risk factors (CVRFs), such as hypertension, hypertriglyceridemia, and low levels of high-density cholesterol (HDL-C). In obese patients with a body mass index (BMI) of >or=40 kg/m2 or 35-40 kg/m2 associated with CVRFs, weight loss may be achieved more effectively by bariatric surgery on reducing several CVRFs. Carotid intima-media thickness (C-IMT) is an indicator of early atherosclerosis, and may be correlated with CVRFs. Our objective was to correlate C-IMT with CVRFs before (baseline data) and after surgery, and to observe whether weight loss is followed by a regression of C-IMT. METHODS: Eighteen women who had undergone bariatric surgery participated in this study. Assessments were carried out on the baseline date, and 3, 6, and 12 months after surgery. Some of the CVRFs analyzed were: total cholesterol (TC) levels, HDL-C, triglycerides to HDL-C ratio (TG/HDL-C) and fasting plasma glucose. C-IMT was measured by B-mode ultrasound. RESULTS: A positive correlation was found between C-IMT and age and triglyceride level (p=0.002 and p=0.02, respectively). Six months after surgery, we found a significant reduction in C-IMT (p<0.05), which was significantly correlated with TG level and systolic pressure (p<0.05). CONCLUSION: The weight loss achieved with bariatric surgery resulted in regression of C-IMT. This regression could be observed 6 months following surgery, with an additional benefit at 12 months. Also, this finding was correlated with a reduction in triglyceride levels and systolic blood pressure.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Arteria Carótida Común/patología , Derivación Gástrica , Obesidad Mórbida/patología , Túnica Íntima/patología , Túnica Media/patología , Adulto , Índice de Masa Corporal , Arteria Carótida Común/diagnóstico por imagen , Estudios de Cohortes , Femenino , Humanos , Persona de Mediana Edad , Obesidad Mórbida/diagnóstico por imagen , Obesidad Mórbida/cirugía , Factores de Riesgo , Túnica Íntima/diagnóstico por imagen , Túnica Media/diagnóstico por imagen , Ultrasonografía , Pérdida de Peso
14.
G Ital Nefrol ; 26(6): 695-703, 2009.
Artículo en Italiano | MEDLINE | ID: mdl-19918752

RESUMEN

High-volume hemofiltration (HVHF) and coupled plasma filtration adsorption (CPFA) have shown potential to improve the treatment of sepsis in animals, but there have been no studies comparing these two treatments in humans. Our aim was to compare the hemodynamic effects of HVHF and CPFA in septic shock patients with acute kidney injury (AKI) undergoing continuous renal replacement therapy (CRRT). We performed a cross-over study enrolling patients with septic shock and AKI who were receiving CRRT. Patients were treated with pulse HVHF and continuous veno-venous hemofiltration (CVV H) on day 1 and CPFA and CVV H on day 2 or vice versa. HVHF was performed for 8-10 hours with a replacement fluid rate of 85 mL/kg/h. CPFA was performed for 8-10 hours with a plasma flow rate of 15%. CVV H was performed for the rest of the day with a replacement fluid rate of 35 mL/kg/h. The primary endpoints were changes in mean arterial pressure, vasopressor requirement (expressed as vasopressor score, VS), and noradrenaline dose after pulse HVHF and CPFA. The two treatments were compared using nonparametric tests. We enrolled 8 patients (median age 70.5 years, SOFA 12.5, SAPS II 69.5). There was a trend towards a reduction in VS with HVHF and CPFA (HVHF p=0.13, CPFA p<0.05). There was no significant difference between the two treatments in terms of percentage change in VS score (p=0.22). The data from this pilot study provide no evidence for a difference in hemodynamic effects between pulse HVHF and CPFA in patients with septic shock already receiving CRRT. A larger sample size is needed to adequately explore this issue.


Asunto(s)
Hemofiltración/métodos , Choque Séptico/terapia , Adsorción , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos
15.
Clin Microbiol Infect ; 25(4): 422-430, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30641229

RESUMEN

BACKGROUND: Viral aetiologies are the most common cause of central nervous system (CNS) infections. Approximately one-half of CNS infections remain of undetermined origin. High-throughput sequencing (HTS) brought new perspectives to CNS infection investigations, allowing investigation of viral aetiologies with an unbiased approach. HTS use is still limited to specific clinical situations. OBJECTIVES: The aim of this review was to evaluate the contribution and pitfalls of HTS for the aetiologic identification of viral encephalitis, meningoencephalitis, and meningitis in CNS patient samples. SOURCES: PubMed was searched from 1 January 2008 to 2 August 2018 to retrieve available studies on the topic. Additional publications were included from a review of full-text sources. CONTENT: Among 366 studies retrieved, 29 used HTS as a diagnostic technique. HTS was performed in cerebrospinal fluid and brain biopsy samples of 307 patients, including immunocompromised, immunocompetent paediatric, and adult cases. HTS was performed retrospectively in 18 studies and prospectively in 11. HTS led to the identification of a potential causal virus in 41 patients, with 11 viruses known and ten not expected to cause CNS infections. Various HTS protocols were used. IMPLICATIONS: The additional value of HTS is difficult to quantify because of various biases. Nevertheless, HTS led to the identification of a viral cause in 13% of encephalitis, meningoencephalitis, and meningitis cases in which various assays failed to identify the cause. HTS should be considered early in clinical management as a complement to routine assays. Standardized strategies and systematic studies are needed for the integration of HTS in clinical management.


Asunto(s)
Encefalitis Viral/virología , Secuenciación de Nucleótidos de Alto Rendimiento , Meningitis Viral/virología , Meningoencefalitis/virología , Virus/clasificación , Virus/genética , Adolescente , Adulto , Anciano , Encéfalo/patología , Niño , Preescolar , Encefalitis Viral/diagnóstico , Femenino , Humanos , Lactante , Masculino , Meningitis Viral/diagnóstico , Meningoencefalitis/diagnóstico , Persona de Mediana Edad , Virus/aislamiento & purificación , Adulto Joven
16.
Biosens Bioelectron ; 24(2): 260-5, 2008 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-18487040

RESUMEN

A photoelectrochemical signal chain sensitive to the presence of superoxide radicals was developed on the basis of CdSe/ZnS quantum dots which were immobilized on gold electrodes using a dithiol compound. The conditions of photo current generation under illumination have been characterized with respect to the dependence on the applied electrode potential, the wavelength of the light beam and the stability of the measurement. Because of photoexcitation electron-hole pair generation is enforced in the nanoparticles enhancing the conductivity of the quantum dot layer. This was independently verified by impedance measurements. In order to observe direct electron transfer with the redox protein cytochrome c different surface modifications of the quantum dots were investigated-mercaptopropionic acid, mercaptosuccinic acid and mercaptopyridine. Varying superoxide concentrations in solution can be detected by an enhanced conversion of superoxide-reduced cytochrome c and thus by an enhanced photo current at the quantum dot modified electrode. The electrode was found to be sensitive to higher nanomolar concentrations of the radical.


Asunto(s)
Electroquímica/instrumentación , Oro/química , Óptica y Fotónica/instrumentación , Puntos Cuánticos , Superóxidos/análisis , Diseño de Equipo , Análisis de Falla de Equipo , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Soluciones
18.
J Leukoc Biol ; 66(3): 462-70, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10496317

RESUMEN

Migration from sites of antigen encounter to lymphoid organs is essential to the strong immunogenic function of dendritic cells (DC). In the skin, migration proceeds through dermal lymphatic vessels and is regulated in an incompletely understood way by inflammatory mediators. We studied the effects of tumor necrosis factor alpha (TNF-alpha) and interleukin-1beta (IL-1beta) in mouse skin organ cultures by direct enumeration of migrating DC and by immunohistochemistry. (1) Neutralizing antibodies to TNF-alpha and IL-1beta inhibited migration of DC, also in human skin explants (TNF-alpha). (2) TNF-alpha at low concentrations (50 U/mL) and IL-1beta (50-3000 U/mL) augmented migration to about 150% of spontaneous migration. (3) High concentrations of TNF-alpha (5000 U/mL) inhibited migration by approximately 50%. (4) DC migration from skin explants of TNF-alpha/lymphotoxin-alpha double-deficient mice and TNF-receptor type 1 and 2 double knockout mice was not impaired. (5) TNF-alpha effects were neutralized by anti-IL-1beta, and vice versa. We conclude that in normal animals both TNF-alpha and IL-1beta are required for DC migration to occur. In the complete absence of one cytokine (TNF-alpha), however, backup mechanisms step in.


Asunto(s)
Quimiotaxis/efectos de los fármacos , Células Dendríticas/efectos de los fármacos , Interleucina-1/farmacología , Células de Langerhans/efectos de los fármacos , Piel/citología , Factor de Necrosis Tumoral alfa/farmacología , Animales , Anticuerpos Monoclonales/farmacología , Medios de Cultivo Condicionados/química , Células Dendríticas/citología , Relación Dosis-Respuesta a Droga , Interacciones Farmacológicas , Humanos , Interleucina-1/antagonistas & inhibidores , Células de Langerhans/citología , Linfotoxina-alfa/genética , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Ratones Noqueados , Técnicas de Cultivo de Órganos , Receptores del Factor de Necrosis Tumoral/deficiencia , Receptores del Factor de Necrosis Tumoral/genética , Receptores del Factor de Necrosis Tumoral/fisiología , Factor de Necrosis Tumoral alfa/administración & dosificación , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Factor de Necrosis Tumoral alfa/deficiencia , Factor de Necrosis Tumoral alfa/genética
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