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1.
Rev Med Liege ; 79(5-6): 436-441, 2024 Jun.
Artículo en Francés | MEDLINE | ID: mdl-38869136

RESUMEN

Prematurity remains a leading cause of mortality and morbidity in neonates and children. Prevention of preterm birth and of its complications is a major public health issue. From before conception to long term follow up, many health actors are engaged in this preventive strategy with the same goal : to give the best quality of life for these vulnerable young patients. We will review different preventive aspects during antenatal and perinatal period, during NICU (Neonatal Intensive Care Unit) stay and after discharge. Prevention of prematurity's complications requires a global approach including respiratory, nutritional and infectious aspects among others. Neuroprotective strategies are a key point of this global approach.


La prématurité reste une cause majeure de mortalité et morbidité néonatales et infantiles. La prévention des naissances prématurées et de leurs complications est donc un enjeu majeur de santé publique. De la période pré-conceptionnelle au suivi à long terme de ces enfants, nombreux sont les acteurs impliqués dans un même objectif : offrir la meilleure qualité de vie à ces jeunes patients vulnérables. Nous reverrons ici différents aspects préventifs en période anténatale, périnatale, lors du séjour en néonatologie et lors du suivi après la sortie. La prévention des complications de la prématurité nécessite une prise en charge globale intégrée incluant, notamment, des aspects ventilatoires, nutritionnels, infectieux, néphrologiques et métaboliques. La neuroprotection est au centre des préoccupations et guide l'ensemble de l'approche.


Asunto(s)
Enfermedades del Prematuro , Recien Nacido Prematuro , Humanos , Recién Nacido , Enfermedades del Prematuro/prevención & control , Embarazo , Femenino , Nacimiento Prematuro/prevención & control
2.
Inorg Chem ; 61(17): 6508-6518, 2022 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-35438982

RESUMEN

In this work, we optimized the synthesis of HfO2 nanoparticles (NPs) with a nonaqueous sol-gel method assisted by microwave heating, with a direct surfactant-free extraction and stabilization in water. To tune the structural, morphological, and photophysical properties, we explored the influence of reaction time, heating temperature, and type and concentration of a salt precursor. The controlled size, shape, crystallinity associated with high stability, a good yield of production, and stabilization in water without any surfactant modification of these HfO2 NPs open possibilities for future optoelectronic and biomedical applications. The investigation of their optical properties, revealed a high absorption in the UV range and the presence of a large band gap, originating in transparency at visible wavelengths. Under UV excitation, photoluminescence (PL) shows three emission bands centered at 305, 381, and 522 nm and are assigned to the vibronic transition of an excited OH•* radical or to a self-trapped exciton, to threefold oxygen vacancies VO3 with recombination to the valence band, and to defect level, respectively. The presence of oxygen vacancies associated with PL properties is particularly attractive for optoelectronic, photocatalysis, scintillator, and UV photosensor applications. Finally, by changing the nature of the hafnium precursor salt, using hafnium ethoxide or hafnium acetylacetonate, low-crystallized and aggregated NPs were obtained, which requires further investigation.


Asunto(s)
Hafnio , Nanopartículas , Hafnio/química , Microondas , Nanopartículas/química , Oxígeno , Agua/química
3.
Int J Mol Sci ; 24(1)2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-36613484

RESUMEN

While it has long been mimicked by simple precipitation reactions under biologically relevant conditions, calcium phosphate biomineralization is a complex process, which is highly regulated by physicochemical factors and involves a variety of proteins and other biomolecules. Alkaline phosphatase (ALP), in particular, is a conductor of sorts, directly regulating the amount of orthophosphate ions available for mineralization. Herein, we explore enzyme-assisted mineralization in the homogeneous phase as a method for biomimetic mineralization and focus on how relevant ionic substitution types affect the obtained minerals. For this purpose, mineralization is performed over a range of enzyme substrate concentrations and fluoride concentrations at physiologically relevant conditions (pH 7.4, T = 37 °C). Refinement of X-ray diffraction data is used to study the crystallographic unit cell parameters for evidence of ionic substitution in the lattice, and infrared (IR) spectroscopy and X-ray photoelectron spectroscopy (XPS) are used for complementary information regarding the chemical composition of the minerals. The results show the formation of substituted hydroxyapatite (HAP) after 48 h mineralization in all conditions. Interestingly, an expansion of the crystalline unit cell with an increasing concentration of the enzyme substrate is observed, with only slight changes in the particle morphology. On the contrary, by increasing the amount of fluoride, while keeping the enzyme substrate concentration unchanged, a contraction of the crystalline unit cell and the formation of elongated, well-crystallized rods are observed. Complementary IR and XPS data indicate that these trends are explained by the incorporation of substituted ions, namely CO32- and F-, in the HAP lattice at different positions.


Asunto(s)
Apatitas , Fluoruros , Fosfatos de Calcio/química , Durapatita/química , Difracción de Rayos X , Catálisis , Calcio/metabolismo
4.
Bioinformatics ; 36(2): 416-421, 2020 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-31350559

RESUMEN

MOTIVATION: The circulating recombinant form of HIV-1 CRF02-AG is the most frequent non-B subtype in Europe. Anti-HIV therapy and pathophysiological studies on the impact of HIV-1 tropism require genotypic determination of HIV-1 tropism for non-B subtypes. But genotypic approaches based on analysis of the V3 envelope region perform poorly when used to determine the tropism of CRF02-AG. We, therefore, designed an algorithm based on information from the gp120 and gp41 ectodomain that better predicts the tropism of HIV-1 subtype CRF02-AG. RESULTS: We used a bio-statistical method to identify the genotypic determinants of CRF02-AG coreceptor use. Toulouse HIV Extended Tropism Algorithm (THETA), based on a Least Absolute Shrinkage and Selection Operator method, uses HIV envelope sequence from phenotypically characterized clones. Prediction of R5X4/X4 viruses was 86% sensitive and that of R5 viruses was 89% specific with our model. The overall accuracy of THETA was 88%, making it sufficiently reliable for predicting the tropism of subtype CRF02-AG sequences. AVAILABILITY AND IMPLEMENTATION: Binaries are freely available for download at https://github.com/viro-tls/THETA. It was implemented in Matlab and supported on MS Windows platform. The sequence data used in this work are available from GenBank under the accession numbers MK618182-MK618417.


Asunto(s)
Infecciones por VIH , VIH-1 , Europa (Continente) , Genotipo , Proteína gp120 de Envoltorio del VIH , Receptores CCR5 , Receptores CXCR4 , Plata , Tropismo Viral
5.
J Antimicrob Chemother ; 74(3): 718-721, 2019 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-30535228

RESUMEN

OBJECTIVES: To determine how the load of rilpivirine-resistant variants (mutational load) influences the virological response (VR) of HIV-1-infected patients to a rilpivirine-based first-line regimen. PATIENTS AND METHODS: Four hundred and eighty-nine patients infected with HIV-1 whose reverse transcriptase gene had been successfully resistance genotyped using next-generation sequencing were given a first-line regimen containing rilpivirine. Variables associated with the VR at 12 months were identified using a logistic model. The results were used to build a multivariate model for each mutational load threshold and the R2 variations were analysed to identify the mutational load threshold that best predicted the VR. RESULTS: The mutational load at baseline was the only variable linked to the VR at 12 months (P  < 0.01). The VR at 12 months decreased from 96.9% to 83.4% when the mutational load was >1700 copies/mL and to 50% when the mutational load was > 9000 copies/mL. The threshold of 9000 copies/mL was associated with the VR at 12 months with an OR of 36.7 (95% CI 4.7-285.1). The threshold of 1700 copies/mL was associated with the VR at 12 months with an OR of 7.2 (95% CI 1.4-36.8). CONCLUSIONS: There is quantifiable evidence that determining a mutational load threshold can be used to identify those patients on a first-line regimen containing rilpivirine who are at risk of virological failure. The clinical management of HIV-infected patients can be improved by evaluating the frequency of mutant variants at a threshold of < 20% together with the plasma HIV-1 viral load at the time of resistance genotyping.


Asunto(s)
Farmacorresistencia Viral , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , VIH-1/genética , Mutación , Rilpivirina/uso terapéutico , Terapia Antirretroviral Altamente Activa , Femenino , Genoma Viral , Genotipo , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Rilpivirina/farmacología , Resultado del Tratamiento , Carga Viral
6.
Rev Med Virol ; 28(5): e1987, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29939461

RESUMEN

Hepatitis E virus genotype 3 (HEV-3) can lead to chronic infection in immunocompromised patients, and ribavirin is the treatment of choice. Recently, mutations in the polymerase gene have been associated with ribavirin failure but their frequency before treatment according to HEV-3 subtypes has not been studied on a large data set. We used single-molecule real-time sequencing technology to sequence 115 new complete genomes of HEV-3 infecting French patients. We analyzed phylogenetic relationships, the length of the polyproline region, and mutations in the HEV polymerase gene. Eighty-five (74%) were in the clade HEV-3efg, 28 (24%) in HEV-3chi clade, and 2 (2%) in HEV-3ra clade. Using automated partitioning of maximum likelihood phylogenetic trees, complete genomes were classified into subtypes. Polyproline region length differs within HEV-3 clades (from 189 to 315 nt). Investigating mutations in the polymerase gene, distinct polymorphisms between HEV-3 subtypes were found (G1634R in 95% of HEV-3e, G1634K in 56% of HEV-3ra, and V1479I in all HEV-3efg, clade HEV-3ra, and HEV-3k strains). Subtype-specific polymorphisms in the HEV-3 polymerase have been identified. Our study provides new complete genome sequences of HEV-3 that could be useful for comparing strains circulating in humans and the animal reservoir.


Asunto(s)
Variación Genética , Genotipo , Virus de la Hepatitis E/clasificación , Virus de la Hepatitis E/genética , Hepatitis E/epidemiología , Hepatitis E/virología , Animales , Francia/epidemiología , Genoma Viral , Humanos , Mutación , Filogenia , Secuenciación Completa del Genoma
7.
Molecules ; 24(5)2019 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-30857260

RESUMEN

A polyol method was used to obtain ultrasmall ZnO nanoparticles (NPs) doped with iron ions and coated with a low molecular weight fucoidan in order to perform in vivo MR and ex vivo fluorescence imaging of athrothrombosis. During the synthesis, the early elimination of water by azeotropic distillation with toluene allowed us to produce NPs which size, determined by XRD and TEM, decreased from 7 nm to 4 nm with the increase of iron/zinc ratios from 0.05 to 0.50 respectively. For the highest iron content (NP-0.50) NPs were evidenced as a mixture of nanocrystals made of wurtzite and cubic phase with a molar ratio of 2.57:1, although it was not possible to distinguish one from the other by TEM. NP-0.50 were superparamagnetic and exhibited a large emission spectrum at 470 nm when excited at 370 nm. After surface functionalization of NP-0.50 with fucoidan (fuco-0.50), the hydrodynamic size in the physiological medium was 162.0 ± 0.4 nm, with a corresponding negative zeta potential of -48.7 ± 0.4 mV, respectively. The coating was evidenced by FT-IR spectra and thermogravimetric analysis. Aqueous suspensions of fuco-0.50 revealed high transverse proton relaxivities (T2) with an r2 value of 173.5 mM-1 s-1 (300 K, 7.0 T) and remained stable for more than 3 months in water or in phosphate buffer saline without evolution of the hydrodynamic size and size distribution. No cytotoxic effect was observed on human endothelial cells up to 48 h with these NPs at a dose of 0.1 mg/mL. After injection into a rat model of atherothrombosis, MR imaging allowed the localization of diseased areas and the subsequent fluorescence imaging of thrombus on tissue slices.


Asunto(s)
Medios de Contraste/química , Compuestos Férricos/química , Nanopartículas/química , Óxido de Zinc/química , Imagen por Resonancia Magnética , Polisacáridos/química
8.
J Antimicrob Chemother ; 73(5): 1152-1157, 2018 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-29444253

RESUMEN

Objectives: To evaluate the diagnostic performance of the Vela next-generation sequencing (NGS) system in conjunction with the Sentosa SQ HIV Genotyping Assay for genotyping HIV-1. Methods: Plasma RNA was extracted and templates prepared with the Sentosa SX instrument before sequencing the HIV-1 polymerase on the Sentosa SQ301 Sequencer (PGM IonTorrent). The Vela NGS System was compared with direct sequencing and the 454 GS-FLX (Roche) and MiSeq (Illumina) systems for genotypic resistance testing on clinical samples. Results: The Vela NGS system detected majority resistance mutations in subtype B and CRF02-AG samples at 500 copies/mL and minority variants with a sensitivity of 5% at 100 000 copies/mL. The Vela NGS system and direct sequencing identified resistance mutations with 97% concordance in 46 clinical samples. Vela identified 1/20 of the 1%-5% mutations identified by 454, 5/12 of the 5%-20% mutations and 60/61 of the >20% mutations. Vela identified 3/14 of the 1%-5% mutations identified by MiSeq, 0/2 of the 5%-20% mutations and 47/47 of the >20% mutations. The resistance mutation quantifications by Vela and 454 were concordant (bias: 2.31%), as were those by Vela and MiSeq (bias: 1.06%). Conclusions: The Vela NGS system provides automated nucleic acid extraction, PCR reagent distribution, library preparation and bioinformatics analysis. The analytical performance was very good when compared with direct sequencing, but was less sensitive than two other NGS platforms for detecting minority variants.


Asunto(s)
Automatización de Laboratorios/métodos , Farmacorresistencia Viral , Técnicas de Genotipaje/métodos , Infecciones por VIH/virología , VIH-1/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Pruebas de Sensibilidad Microbiana/métodos , Biología Computacional/métodos , Genes Virales , Genotipo , VIH-1/efectos de los fármacos , VIH-1/aislamiento & purificación , Mutación , ARN Viral/genética , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genética
9.
J Med Virol ; 90(9): 1486-1492, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29750364

RESUMEN

The present study compares the performances of an in-house sequencing protocol developed on MiSeq, the Sanger method, and the 454 GS-FLX for detecting and quantifying drug-resistant mutations (DRMs) in the human immunodeficiency virus polymerase gene (reverse transcriptase [RT] and protease [PR]). MiSeq sequencing identified all the resistance mutations detected by bulk sequencing (n = 84). Both the MiSeq and 454 GS-FLX platforms identified 67 DRMs in the RT and PR regions, but a further 25 DRMs were identified by only one or other of them. Pearson's analysis showed good concordance between the percentage of drug-resistant variants determined by MiSeq and 454 GS-FLX sequencing (ρ = .77, P < .0001). The MiSeq platform is as accurate as the 454 GS-FLX Roche system for determining RT and PR DRMs and could be used for monitoring human immunodeficiency virus type 1 drug resistance.


Asunto(s)
Variación Genética , Infecciones por VIH/virología , VIH-1/clasificación , VIH-1/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Mutación , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genética , Farmacorresistencia Viral , Proteasa del VIH/genética , Transcriptasa Inversa del VIH/genética , VIH-1/aislamiento & purificación , Humanos
10.
Eur J Pediatr ; 175(12): 1933-1942, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27678511

RESUMEN

Less invasive surfactant therapies (LIST) use surfactant instillation through a thin tracheal catheter in spontaneously breathing infants. This review and meta-analysis investigates respiratory outcomes for preterm infants with respiratory distress syndrome treated with LIST rather than administration of surfactant through an endotracheal tube. Randomised controlled trial (RCT) full texts provided outcome data for bronchopulmonary dysplasia (BPD), death or BPD, early CPAP failure, invasive ventilation requirements and usual neonatal morbidities. Relative risks (RR) from pooled data, with subgroup analyses, were obtained from a Mantel-Haenszel analysis using a random effect model. Six RCTs evaluated LIST: 4 vs InSurE and 1 each vs delayed or immediate intubation for surfactant. LIST resulted in decreased risks of BPD (RR = 0.71 [0.52-0.99]; NNT = 21), death or BPD (RR = 0.74 [0.58-0.94]; NNT = 15) and early CPAP failure or invasive ventilation requirements (RR = 0.67 [0.53-0.84]; NNT = 8 and RR = 0.69 [0.53-0.88]; NNT = 6). Compared to InSurE, LIST decreased the risks of BPD or death (RR = 0.63 [0.44-0.92]; NNT = 11) and of early CPAP failure (RR = 0.71 [0.53-0.96]; NNT = 11). Common neonatal morbidities were not different. CONCLUSIONS: Respiratory management with LIST decreases the risks of BPD and BPD or death, and the need for invasive ventilation. This strategy appears safe, but long-term follow-up is lacking. What is Known: • Initial management of preterm infants with CPAP decreases the risk of death or BPD, but many still require surfactant or invasive ventilation. • Surfactant can be instilled through a tracheal thin catheter while the infant breathes on CPAP, but improvement in BPD is inconsistent between studies. What is New: • Less invasive surfactant therapy (LIST) strategies decrease the risks of BPD, of death or BPD, and of CPAP failure compared to strategies where surfactant is administered through an endotracheal tube. • LIST strategies decrease the risks of the composite outcome of BPD or death and of early CPAP failure when compared to "intubation-surfactant-extubation" approaches.


Asunto(s)
Presión de las Vías Aéreas Positiva Contínua/métodos , Intubación Intratraqueal/métodos , Surfactantes Pulmonares/administración & dosificación , Síndrome de Dificultad Respiratoria del Recién Nacido/terapia , Displasia Broncopulmonar/prevención & control , Terapia Combinada , Humanos , Recién Nacido , Recien Nacido Prematuro , Ensayos Clínicos Controlados Aleatorios como Asunto
11.
Antimicrob Agents Chemother ; 60(3): 1608-14, 2015 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-26711757

RESUMEN

Hepatitis E virus (HEV) can lead to chronic infection in solid-organ transplant patients. Ribavirin is efficient for treatment of chronically infected patients. Recently, the1634R mutation in the HEV polymerase has been associated with treatment failure. However, it is unclear if this mutation can be used as a prognostic marker of treatment outcome. We studied the prevalence of the 1634R mutation in the HEV polymerase of patients starting ribavirin therapy, the influence of the 1634R variants on the viral response, the frequency of the 1634R mutation in patients whose treatment failed, and its impact on ribavirin retreatment. We analyzed pretreatment samples from 63 solid-organ transplant patients with chronic hepatitis E using deep sequencing; 42 patients had a sustained virologic response (SVR), and 21 were non-SVR patients. We detected the 1634R variant by deep sequencing in 36.5% (23/63) of the patients (proportions, 1.3 to 100%). The 1634R variant was detected in 31.0% (13/42) of baseline plasma samples from patients with SVR and in 47.6% (10/21) in the other patients (P = 0.2). The presence of this mutation did not influence the initial decrease in viral RNA. Lastly, a second prolonged ribavirin treatment led to SVR in 70% of the patients who initially did not have SVR, despite the presence of the 1634R variant. We conclude that the presence of the 1634R variant at ribavirin initiation does not lead to absolute ribavirin resistance. Although its proportion increased in patients whose treatment failed, the presence of the 1634R variant did not compromise the response to a second ribavirin treatment.


Asunto(s)
Antivirales/uso terapéutico , Virus de la Hepatitis E/efectos de los fármacos , Virus de la Hepatitis E/genética , Hepatitis E/tratamiento farmacológico , ARN Polimerasa Dependiente del ARN/genética , Ribavirina/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Secuencia de Bases , Niño , Femenino , Marcadores Genéticos , Hepatitis E/virología , Humanos , Masculino , Persona de Mediana Edad , Mutación/genética , ARN Viral/genética , Análisis de Secuencia de ARN , Resultado del Tratamiento , Adulto Joven
12.
Int J Biol Macromol ; 254(Pt 2): 127695, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37913877

RESUMEN

The use of water-dispersible and sustainable Pd nanocatalysts to reduce toxic heavy metal ions and catalyze important organic reactions has profound significance for the environmental remediation and the catalytic industry. In this work, a novel water-dispersible and recyclable Pd@LNPs nanoreactor composed of Pd nanoparticle cluster core and LNPs shell was developed in microwave reactor in aqueous solution. It turned out that Pd nanoparticles grew uniformly and stably inside LNPs nanosphere due to the coordinated binding and interaction between Pd and the functional groups in LNPs, which was significantly different from surface loading. The green and biodegradable LNPs nanospheres are not only used as reducing agents for Pd (II) and nanocarriers, but also act as individual nanocontainers to provide favorable sites for reactions and effectively control the entry and release of reactants and products. Furthermore, the excellent and efficient catalytic properties of Pd@LNPs were exhibited by CC coupling reactions and the reduction of Cr(VI) and 4-nitrophenol. The Pd@LNPs prepared in this study have the advantages of excellent dispersion, great recyclability, high turnover frequency and better green sustainability metrics. It will have a great significance for the development of the potential high-value of lignin and the progress in the field of bio-nanocatalysts.


Asunto(s)
Nanopartículas , Nanosferas , Paladio/química , Nanotecnología
13.
Neonatology ; 119(2): 137-150, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35124678

RESUMEN

BACKGROUND: Surfactant therapy is the cornerstone of respiratory distress syndrome management. "Less-invasive surfactant administration (LISA)" is now recommended for spontaneously breathing preterm infants. Analgosedation remains controversial as 52% of European neonatologists do not use any. This systematic review aims to describe the efficacy and safety of different drugs for analgosedation during LISA. METHODS: MEDLINE via Ovid, Embase, Scopus, and Cochrane Library of Trials were searched independently by 2 reviewers for studies on sedation or analgesia for LISA, without filters or limits. RESULTS: Eight studies (1 randomized controlled trial) recruiting 945 infants were included. Infant pain was significantly reduced, with more infants evaluated as comfortable. Failure, defined as need for intubation or for a second dose of surfactant, was not different between sedated and unsedated groups. Analgosedation was associated with a higher occurrence of desaturation and need for positive pressure ventilation during procedure, but the need for mechanical ventilation within 24 or 72 h of life was not significantly different. There does not seem to be any difference in clinical tolerance and complications (e.g., hypotension, mortality, air leaks, etc.). Procedural conditions were evaluated as good or excellent in 83% after sedation. DISCUSSION AND CONCLUSION: Analgesia or sedative drugs increase infant comfort and allow good procedural conditions, with a limited impact on the clinical evolution. Questions remain about the best choice of drugs and dosages, with the constraint to maintain spontaneous breathing and have a rapid offset. Further good quality studies are needed to provide additional evidence to supplement those limited existing data.


Asunto(s)
Surfactantes Pulmonares , Síndrome de Dificultad Respiratoria del Recién Nacido , Humanos , Lactante , Recién Nacido , Recien Nacido Prematuro , Surfactantes Pulmonares/uso terapéutico , Respiración Artificial/métodos , Síndrome de Dificultad Respiratoria del Recién Nacido/tratamiento farmacológico , Tensoactivos
14.
Int J Biol Macromol ; 222(Pt B): 1830-1839, 2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36191789

RESUMEN

In order to further develop the potential applications of lignin biomass, the research on lignin nanoparticles (LNPs) and their nanocomposites has attracted increasing attention. In this study, a facile and no chemical modification approach to prepare stable alkali lignin nanospheres is presented. The nanospheres around 85-125 nm were prepared through the π-π interactions between molecules in the self-assembly process. Lignin alkali was dissolved in ethylene glycol at different initial concentrations and subsequently ultrasound and dialysis treatment were conducted to prepare LNPs. The prepared LNPs had zeta potentials between -20 mV and -40 mV, and they were electrostatically stable over the pH range of 3 to 12 in aqueous solution. The chemical structure of LNPs was not significantly modified compared to lignin. Meanwhile the increased content of carboxyl and aliphatic hydroxyl groups in the LNPs structure was observed. Furthermore, the thermal stability and solubility in organic solvents (ethanol, acetone and THF) of LNPs were enhanced compared to those of lignin. In vitro cell viability evaluation indicated that the prepared LNPs had no cytotoxicity and excellent biocompatibility with mouse fibroblast. Therefore, we proposed here the production of high-quality and renewable LNPs, which will provide a novel perspective for multifunctional applications of bio-based nanomaterials.


Asunto(s)
Lignina , Nanopartículas , Ratones , Animales , Lignina/química , Álcalis , Diálisis Renal , Nanopartículas/química , Biomasa
15.
J Clin Virol ; 122: 104229, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31809945

RESUMEN

BACKGROUND: Patients on antiretroviral therapy could benefit from HIV-1 DNA resistance genotyping for exploring virological failure with low viral load or to guide treatment simplification. Few new generation sequencing data are available. OBJECTIVE: To check that the automated deep sequencing Sentosa platform (Vela DX) detected minority resistant variants well enough for HIV DNA genotyping. STUDY DESIGN: We evaluated the Sentosa SQ HIV genotyping assay with automated extraction on 40 DNA longitudinal samples from treatment-experienced patients by comparison with Sanger sequencing. HIV drug resistance was interpreted using the ANRS algorithm (v29) at the threshold of 20 % and 3 %. RESULTS: The Sentosa SQ HIV genotyping assay was 100 % successful to amplify and sequence PR and RT and 86 % to amplify and sequence IN when the HIV DNA load was >2.5 log copies/million cells. The Sentosa and Sanger sequencing were concordant for predicting PR-RT resistance at the threshold of 20 % in 14/18 samples successfully sequenced. A higher level of resistance was predicted by Sentosa in three samples and by Sanger in one sample. The prevalence of resistance was 7 % to PI, 59 % to NRTI, 31 % to NNRTI and 20 % to integrase inhibitors using the Sentosa SQ genotyping assay at the threshold of 3 %. Seven additional mutations <20 % were detected using the Sentosa assay. CONCLUSION: Automated DNA extraction and sequencing using the Sentosa SQ HIV genotyping assay accurately predicted HIV DNA drug resistance by comparison with Sanger. Prospective studies are needed to evaluate the clinical interest of HIV DNA genotyping.


Asunto(s)
Farmacorresistencia Viral/genética , Técnicas de Genotipaje/métodos , VIH-1/genética , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Automatización de Laboratorios , Infecciones por VIH/virología , VIH-1/efectos de los fármacos , Humanos , Estudios Longitudinales , Mutación , ARN Viral/sangre , Carga Viral
16.
Front Microbiol ; 11: 1, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32082274

RESUMEN

Recombinant strains of hepatitis E virus (HEV) with insertions of human genomic fragments or HEV sequence duplications in the sequence encoding the polyproline region (PPR) were previously described in chronically infected patients. Such genomic rearrangements confer a replicative advantage in vitro but little is known about their frequency, location, or origin. As the sequences of only a few virus genomes are available, we analyzed the complete genomes of 114 HEV genotype 3 strains from immunocompromised (n = 85) and immunocompetent (n = 29) patients using the single molecular real-time sequencing method to determine the frequency, location, and origin of inserted genomic fragments, plus the proportions of variants with genomic rearrangements in each virus quasispecies. We also examined the amino acid compositions and post-translational modifications conferred by these rearrangements by comparing them to sequences without human gene insertions or HEV gene duplications. We found genomic rearrangements in 7/114 (6.1%) complete genome sequences (4 HEV-3f, 1 HEV-3e, 1 HEV-3 h, and 1 HEV-3chi-new), all from immunocompromised patients, and 3/7 were found at the acute phase of infection. Six of the seven patients harbored virus-host recombinant variants, including one patient with two different recombinant variants. We also detected three recombinant variants with genome duplications of the PPR or PPR + X domains in a single patient. All the genomic rearrangements (seven human fragment insertions of varying origins and three HEV genome duplications) occurred in the PPR. The sequences with genomic rearrangements had specific characteristics: increased net load (p < 0.001) and more ubiquitination (p < 0.001), phosphorylation (p < 0.001), and acetylation (p < 0.001) sites. The human fragment insertions and HEV genome duplications had slightly different characteristics. We believe this is the first description of HEV strains with genomic rearrangements in patients at the acute phase of infection; perhaps these strains are directly transmitted. Clearly, genomic rearrangements produce a greater net load with duplications and insertions having different features. Further studies are needed to clarify the mechanisms by which such modifications influence HEV replication.

17.
Ultrason Sonochem ; 52: 280-285, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30555040

RESUMEN

The ultrasound (US) assisted extraction of bio-compounds from different fruit skins (apples, bananas and persimmons) was studied. The aqueous suspensions of skins were treated by US with different energy inputs (0.033-0.299 kW·h/kg) and total time of aqueous extraction was up to 2700 s. The ionic, Zi, and total polyphenol, Zp, extraction indexes of the liquid extracts were analyzed. From microscopic images the cell wall disintegration index, Zm, was determined. Increase in US energy input caused the increase of values of Zi, Zp and Zm. The correlations between extraction parameters and the disintegration index, Zm, were discussed.


Asunto(s)
Fraccionamiento Químico/métodos , Frutas/química , Polifenoles/aislamiento & purificación , Ondas Ultrasónicas , Frutas/citología , Polifenoles/análisis , Agua/química
18.
Nanomaterials (Basel) ; 9(12)2019 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-31795284

RESUMEN

The framework of this work was to develop an emulsion-based edible film based on a chitosan nanoparticle matrix with cellulose nanocrystals (CNCs) as a stabilizer and reinforcement filler. The chitosan nanoparticles were synthesized based on ionic cross-linking with sodium tripolyphosphate and glycerol as a plasticizer. The emulsified film was prepared through a combination system of Pickering emulsification and water evaporation. The oil-in-water emulsion was prepared by dispersing beeswax into an aqueous colloidal suspension of chitosan nanoparticles using high-speed homogenizer at room temperature. Various properties were characterized, including surface morphology, stability, water vapor barrier, mechanical properties, compatibility, and thermal behaviour. Experimental results established that CNCs and glycerol improve the homogeneity and stability of the beeswax dispersed droplets in the emulsion system which promotes the water-resistant properties but deteriorates the film strength at the same time. When incorporating 2.5% w/w CNCs, the tensile strength of the composite film reached the maximum value, 74.9 MPa, which was 32.5% higher than that of the pure chitosan film, while the optimum one was at 62.5 MPa, and was obtained by the addition of 25% w/w beeswax. All film characterizations demonstrated that the interaction between CNCs and chitosan molecules improved their physical and thermal properties.

19.
AIDS ; 33(13): 1977-1985, 2019 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-31259760

RESUMEN

OBJECTIVE: To study the long-term evolution of the transmitted CXCR4-using viruses. CCR5-using viruses (R5 viruses) predominate during primary HIV-1 infections (PHI) while CXCR4-using viruses are isolated in less than 10% of PHI. DESIGN: Six patients infected with an R5X4 virus, detected by a sensitive phenotypic assay during PHI, were matched with six patients infected with a pure R5 virus for sex, Fiebig stage, time of antiretroviral initiation and duration of follow-up. METHODS: We used MiSeq ultra-deep sequencing to determine the composition of the virus quasispecies during PHI and at the end of follow-up (median time of follow-up: 12.5 years). RESULTS: X4 viruses were detected by genetic analysis in three of six samples from the R5X4 group, accounting for 1.3-100% of the virus quasispecies, during PHI, and in four of six samples (accounting for 6.7-100%) at the end of follow-up. No X4 virus was detected in the R5 group during PHI and in only one patient (accounting for 1.2%) at the end of follow-up. The complexity of the virus quasispecies at the stage of PHI was higher in the R5X4 group than in the R5 group. Complexity increased from PHI to the end of follow-up in the R5 group but remained stable in the R5X4 group. CONCLUSION: CXCR4-using viruses persisted in the peripheral blood mononuclear cells of several patients on suppressive antiretroviral therapy for a median duration of 12.5 years after PHI. The genetic complexity of HIV-1 evolved differently post-PHI in patients infected with R5X4 viruses from those infected with R5 viruses.


Asunto(s)
Evolución Molecular , Infecciones por VIH/virología , VIH-1/genética , Receptores CXCR4/metabolismo , Tropismo Viral , Productos del Gen env del Virus de la Inmunodeficiencia Humana/genética , Fármacos Anti-VIH/uso terapéutico , Recuento de Linfocito CD4 , Femenino , Infecciones por VIH/tratamiento farmacológico , VIH-1/fisiología , Interacciones Huésped-Patógeno , Humanos , Masculino , Datos de Secuencia Molecular , Receptores CCR5/metabolismo
20.
Resuscitation ; 120: 20-25, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-28860014

RESUMEN

BACKGROUND: Starting resuscitation before clamping the umbilical cord at birth may progressively increase pulmonary blood flow while umbilical venous blood flow is still contributing to maintenance of oxygenation and left ventricle preload. OBJECTIVE: To evaluate the feasibility, safety, and effects of intact cord resuscitation (ICR) on cardiorespiratory adaptation at birth in newborn infants with CDH. STUDY DESIGN: Prospective, observational, single-center pilot study. METHODS: Physiologic variables and outcomes were collected prospectively in 40 consecutive newborn infants with an antenatal diagnosis of isolated CDH. RESULTS: Infants were managed with immediate cord clamping (ICC group) from 1/2012 to 5/2014 or the cord was clamped after initiation of resuscitation maneuvers (ICR group) from 6/2014 to 4/2016 (20 in each group). Ante- and postnatal markers of CDH severity were similar between groups. Resuscitation before cord clamping was possible for all infants in the ICR group. No increase in maternal or neonatal adverse events was observed during the period of ICR. The pH was higher and the plasma lactate concentration was significantly lower at one hour after birth in the ICR than in the ICC group (pH=7.17±0.1 vs 7.08±0.2; lactate=3.6±2.3 vs 6.6±4.3mmol/l, p<0.05). Mean blood pressure was significantly higher in the ICR than in the ICC group at H1 (52±7.7 vs 42±7.5mmHg), H6 (47±3.9 vs 40±5.6mmHg) and H12 (44±2.9 vs 39±3.3mmHg) (p<0.05). CONCLUSION: Commencing resuscitation and initiating ventilation while the infant is still attached to the placenta is feasible in infants with CDH. The procedure may support the cardiorespiratory transition at birth in infants with CDH.


Asunto(s)
Parto Obstétrico/métodos , Hernias Diafragmáticas Congénitas , Resucitación/métodos , Cordón Umbilical , Adulto , Puntaje de Apgar , Estudios de Factibilidad , Femenino , Edad Gestacional , Humanos , Recién Nacido , Intubación Intratraqueal/métodos , Masculino , Proyectos Piloto , Embarazo , Estudios Prospectivos , Seguridad , Factores de Tiempo , Adulto Joven
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