973 research outputs found

    Survivability of entrapped Lactobacillus rhamnosus in liquid- and gel-core alginate beads during storge and simulated gastrointestinal conditions

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    L. rhamnosus cells were encapsulated in liquid-core (LCBR) and gel-core (GCBR) calcium alginate beads, and cell survivability under storage conditions and simulated gastrointestinal conditions were evaluated, and compared with that of non-encapsulated cells. The average external diameters of both beads (1.37 - 0.25 mm) were non-significantly dierent, and the average thickness of alginate gelled layer in LCBR was of 0.27 - 0.01 mm. The bacteria entrapped into LCBR tended to gather together forming clusters in the bulk of the liquid phase of the bead, whereas the bacteria entrapped into GCBR were compartmentalized in the gelled bead biopolymer matrix. LCBR showed significant lower hardness and chewiness, higher cohesiveness, and comparable springiness values than GCBR. Cells survivability under storage and simulated gastrointestinal conditions was significantly higher in LCBR than in GCBR and for the non-encapsulated free cells

    Microbiological contamination of conventional and reclaimed irrigation water: evaluation and management measures

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    The wide diversity of irrigation water sources (i.e., drinking water, groundwater, reservoir water, river water) includes reclaimed water as a requested measure for increasing water availability, but it is also a challenge as pathogen exposure may increase. This study evaluates the level of microbial contamination in different irrigation waters to improve the knowledge and analyses management measures for safety irrigation. Over a one-year period, the occurrence of a set of viruses, bacteria and protozoa, was quantified and the performance of a wetland system, producing reclaimed water intended for irrigation, was characterized. Human fecal pollution (HAdV) was found in most of the irrigation water types analysed. Hepatitis E virus (HEV), an emerging zoonotic pathogen, was present in groundwater where porcine contamination was identified (PAdV). The skin-carcinoma associated Merkel cell polyomavirus (MCPyV), was found occasionally in river water. Noroviruses were detected, as expected, in winter, in river water and reclaimed water. Groundwater, river water and reservoir water also harboured potential bacterial pathogens, like Helicobacter pylori, Legionella spp. and Aeromonas spp. that could be internalized and viable inside amoebas like Acanthamoeba castellanii, which was also detected. Neither Giardia cysts, nor any Cryptosporidium oocysts were detected. The wetland system removed 3 Log10 of viruses and 5 Log10 of bacteria, which resembled the river water quality. Irrigation waters were prone to variable contamination levels and according to the European guidance documents, the E. coli (EC) levels were not always acceptable. Sporadic detection of viral pathogens as NoV GII and HAdV was identified in water samples presenting lower EC than the established limit (100MNP/100 mL). When dealing with reclaimed water as a source of irrigation the analysis of some viral parameters, like HAdV during the peak irrigation period (summer and spring) or NoV during the coldest months, could complement existing water management tools based on bacterial indicators

    Antibody recognition of the glycoprotein g of viral haemorrhagic septicemia virus (VHSV) purified in large amounts from insect larvae

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    <p>Abstract</p> <p>Background</p> <p>There are currently no purification methods capable of producing the large amounts of fish rhabdoviral glycoprotein G (gpG) required for diagnosis and immunisation purposes or for studying structure and molecular mechanisms of action of this molecule (ie. pH-dependent membrane fusion). As a result of the unavailability of large amounts of the gpG from viral haemorrhagic septicaemia rhabdovirus (VHSV), one of the most dangerous viruses affecting cultured salmonid species, research interests in this field are severely hampered. Previous purification methods to obtain recombinant gpG from VHSV in <it>E. coli</it>, yeast and baculovirus grown in insect cells have not produced soluble conformations or acceptable yields. The development of large-scale purification methods for gpGs will also further research into other fish rhabdoviruses, such as infectious haematopoietic necrosis virus (IHNV), spring carp viremia virus (SVCV), hirame rhabdovirus (HIRRV) and snakehead rhabdovirus (SHRV).</p> <p>Findings</p> <p>Here we designed a method to produce milligram amounts of soluble VHSV gpG. Only the transmembrane and carboxy terminal-deleted (amino acid 21 to 465) gpG was efficiently expressed in insect larvae. Recognition of G21-465 by ß-mercaptoethanol-dependent neutralizing monoclonal antibodies (N-MAbs) and pH-dependent recognition by sera from VHSV-hyperimmunized or VHSV-infected rainbow trout (<it>Oncorhynchus mykiss</it>) was demonstrated.</p> <p>Conclusions</p> <p>Given that the purified G21-465 conserved some of its most important properties, this method might be suitable for the large-scale production of fish rhabdoviral gpGs for use in diagnosis, fusion and antigenicity studies.</p

    El pirocloro (H3O)NbWO6-nH2O como catalizador para la deshidratación de Fructosa a 5-hidroximetilfurfural (HMF)

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    5-hidroximetilfurfural (HMF) es una importante molécula plataforma en la síntesis de diversos productos químicos. En este trabajo, informamos la deshidratación de fructosa a HMF en un sistema bifásico que contiene H2O y MIBK-2-ButOH como fase orgánica y (H3O)NbWO6-nH2O con estructura pirocloro como catalizador. El pirocloro se preparó por química del estado sólido a partir del precursor KNbWO6, seguido de un intercambio iónico en ácido sulfúrico. Este sólido exhibió una alta acidez, demostrando ser activo como catalizador ácido en la deshidratación de fructosa a (HMF). El catalizador es muy estable, ya que no se observó lixiviación de especies de niobio y wolframio a la fase líquida. Los resultados mostraron que el catalizador tiene un efecto catalítico sinérgico positivo en la conversión de fructosa a HMF. El rendimiento más alto de HMF del 33 % se logró a 150 ° C durante 90 min.Fil: Mayer, Sergio Federico. Universidad Tecnológica Nacional. Facultad Regional Córdoba. Centro de Investigación en Nanociencia y Nanotecnología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Falcon, Horacio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigación y Tecnología Química. Universidad Tecnológica Nacional. Facultad Regional Córdoba. Centro de Investigación y Tecnología Química; ArgentinaFil: Poncio, Carlos Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Centro de Investigación y Tecnología Química. Universidad Tecnológica Nacional. Facultad Regional Córdoba. Centro de Investigación y Tecnología Química; ArgentinaFil: Ribotta, Pablo Daniel. Universidad Nacional de Córdoba. Secretaría de Ciencia y Tecnología. Instituto Superior de Investigación, Desarrollo y Servicio de Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba; ArgentinaFil: Perez, Susana. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Morales delaRosa, Silvia. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Campos Martín, José M.. Instituto de Ciencia de Materiales de Madrid; EspañaFil: Alonso, José Antonio. Consejo Superior de Investigaciones Científicas. Instituto de Catálisis y Petroleoquímica; EspañaFil: Fierro, José Luis G.. Instituto de Ciencia de Materiales de Madrid; EspañaXXI Congreso Argentino de Catálisis y X Congreso de Catálisis del MercosurSanta FeArgentinaSociedad Argentina de CatálisisInstituto de Investigaciones en Catálisis y PetroquímicaInstituto de Desarrollo Tecnológico para la Industria Químic

    Obstetric outcomes of sars-cov-2 infection in asymptomatic pregnant women

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    Altres ajuts: Fondo Europeo de Desarrollo Regional (FEDER)Around two percent of asymptomatic women in labor test positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in Spain. Families and care providers face childbirth with uncertainty. We determined if SARS-CoV-2 infection at delivery among asymptomatic mothers had different obstetric outcomes compared to negative patients. This was a multicenter prospective study based on universal antenatal screening for SARS-CoV-2 infection. A total of 42 hospitals tested women admitted for delivery using polymerase chain reaction, from March to May 2020. We included positive mothers and a sample of negative mothers asymptomatic throughout the antenatal period, with 6-week postpartum follow-up. Association between SARS-CoV-2 and obstetric outcomes was evaluated by multivariate logistic regression analyses. In total, 174 asymptomatic SARS-CoV-2 positive pregnancies were compared with 430 asymptomatic negative pregnancies. No differences were observed between both groups in key maternal and neonatal outcomes at delivery and follow-up, with the exception of prelabor rupture of membranes at term (adjusted odds ratio 1.88, 95% confidence interval 1.13-3.11; p = 0.015). Asymptomatic SARS-CoV-2 positive mothers have higher odds of prelabor rupture of membranes at term, without an increase in perinatal complications, compared to negative mothers. Pregnant women testing positive for SARS-CoV-2 at admission for delivery should be reassured by their healthcare workers in the absence of symptoms

    Centromere protein A dynamics in human pluripotent stem cell self-renewal, differentiation and DNA damage

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    Human pluripotent stem cells (hPSCs) hold significant promise for use in regenerative medicine, or as a model to understand human embryo development. However, the basic mechanisms required for proliferation and self-renewal of hPSCs have not been fully uncovered. Proliferation in all eukaryotes is dependent upon highly regulated expression of the histone H3 variant Centromere protein A (CENP-A). In the current study, we demonstrate that hPSCs have a unique messenger ribonucleic acid (mRNA) reserve of CENP-A not found in somatic fibroblasts. Using short hairpin RNA technology to reduce but not ablate CENP-A, we show that CENP-A-depleted hPSCs are still capable of maintaining a functional centromeric mark, whereas fibroblasts are not. However, upon induction of differentiation or DNA damage, hPSCs with depleted CENP-A arrest in G2/M and undergo apoptosis. Analysis of CENP-A dynamics following DNA damage in hPSCs reveals that 60 min after irradiation, CENP-A is found in multiple small nuclear foci that are mutually exclusive to γH2AX as well as CENP-C. Furthermore, following irradiation, hPSCs with depleted CENP-A mount a normal apoptotic response at 6 h; however at 24 h, apoptosis is significantly increased in CENP-A-depleted hPSCs relative to control. Taken together, our results indicate that hPSCs exhibit a unique mechanism for maintaining genomic integrity by possessing the flexibility to reduce the amount of CENP-A required to maintain a functional centromere under self-renewing conditions, and maintaining a reserve of CENP-A mRNA to rebuild the centromere following differentiation or DNA damage

    Multicentre, randomised, single-blind, parallel group trial to compare the effectiveness of a Holter for Parkinson's symptoms against other clinical monitoring methods: study protocol

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    Introduction In recent years, multiple studies have aimed to develop and validate portable technological devices capable of monitoring the motor complications of Parkinson's disease patients (Parkinson's Holter). The effectiveness of these monitoring devices for improving clinical control is not known. Methods and analysis This is a single-blind, cluster-randomised controlled clinical trial. Neurologists from Spanish health centres will be randomly assigned to one of three study arms (1:1:1): (a) therapeutic adjustment using information from a Parkinson?s Holter that will be worn by their patients for 7 days, (b) therapeutic adjustment using information from a diary of motor fluctuations that will be completed by their patients for 7 days and (c) therapeutic adjustment using clinical information collected during consultation. It is expected that 162 consecutive patients will be included over a period of 6 months. The primary outcome is the efficiency of the Parkinson?s Holter compared with traditional clinical practice in terms of Off time reduction with respect to the baseline (recorded through a diary of motor fluctuations, which will be completed by all patients). As secondary outcomes, changes in variables related to other motor complications (dyskinesia and freezing of gait), quality of life, autonomy in activities of daily living, adherence to the monitoring system and number of doctor?patient contacts will be analysed. The noninferiority of the Parkinson's Holter against the diary of motor fluctuations in terms of Off time reduction will be studied as the exploratory objective. Ethics and dissemination approval for this study has been obtained from the Hospital Universitari de Bellvitge Ethics Committee. The results of this study will inform the practical utility of the objective information provided by a Parkinson's Holter and, therefore, the convenience of adopting this technology in clinical practice and in future clinical trials. We expect public dissemination of the results in 2022.Funding This work is supported by AbbVie S.L.U, the Instituto de Salud Carlos III [DTS17/00195] and the European Fund for Regional Development, 'A way to make Europe'
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