152 research outputs found

    Solar photoelectro-Fenton-like process with anodically-generated HClO in a flow reactor: Norfloxacin as a pollutant with a particular structure

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    The degradation and mineralization of the drug norfloxacin (NFX) has been assessed in a model solution, containing 15 mM NaCl +45 mM Na2SO4 at pH 3.0, using a flow plant with an FM01-LC filter-press reactor equipped with a Ti|Ir-Sn-Ru oxides anode to electrogenerate HClO from Cl- oxidation and a stainless-steel cathode. Unexpectedly, anodic oxidation with active chlorine (AO-HClO) outperformed electro-Fenton (EF-HClO), photoelectro-Fenton (PEF-HClO) and solar photoelectro-Fenton (SPEF-HClO) due to: (i) the formation of refractory complexes between iron ions and carboxyl group of NFX, and (ii) the conversion of HClO into less effective ¿OH upon its Fenton-like reaction with added Fe2+ catalyst. SPEF-HClO was superior among Fentonbased treatments because the ¿OH concentration was largely increased by the photolysis of Fe(III) species. At an initial NFX concentration in the range 0.103-0.146 mM, the optimum conditions for SPEF-HClO were 0.40 mM Fe2+ and 15 mA cm 2. A BDD anode allowed a higher production of ¿OH, accelerating the degradation and mineralization, with similar energy requirements as compared to trials with Ti|Ir-Sn-Ru oxides anode. The SPEFHClO process in urban wastewater was less powerful because of the parallel oxidation of natural organic matter. HClO, Fe2+ and Fetotal were quantified in both water matrices. The initial degradation sequence for NFX, proposed from 10 primary by-products identified by LC-MS/MS, revealed the occurrence of hydroxylation, chlorination and defluorination steps. Additionally, 5 stable by-products were detected by GC-MS

    Ectoparásitos en branquias de tilapias adultas (Oreochromis niloticus) del Sector Bello Horizonte de la Banda de Shilcayo, San Martín, Perú

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    The aim of this study was to determine the presence of ectoparasites in the gills of 73 adult tilapia (Oreochromis niloticus) from seven ponds located in the Bello Horizonte Sector, Banda de Shilcayo district, San Martín, Peru. Sampling was carried out between January and February 2021. Measurements of size, temperature and pH of the ponds were recorded and the measurements of the ponds and fish density were obtained from fish farms records. The fish were taken to the laboratory for the dissection of the gills and the collection and fixation of the ectoparasites. Results showed that 35.6% (26/73) of fish were infested with one or more ectoparasites. The presence of monogeneans of the genus Chclidogyrus sp, family Dactylogyridae (28.8%) and the protozoan Trichodina sp (11.0%) (8/73) was determined.El objetivo del presente estudio fue determinar la presencia de ectoparásitos en branquias de 73 tilapias adultas (Oreochromis niloticus) provenientes de siete pozas ubicadas en el Sector Bello Horizonte, distrito de la Banda de Shilcayo, San Martín, Perú. Se realizó el muestreo entre enero a febrero de 2021. Se realizaron mediciones de tamaño, temperatura y pH de las pozas y se obtuvieron las medidas de las pozas y densidad de los peces a partir de los registros de las piscigranjas. Los peces fueron llevados al laboratorio para la disección de las branquias y la colecta y fijación de los ectoparásitos. El 35.6% (26/73) de peces estuvieron infestados con uno o más ectoparásitos. Se determinó la presencia de monogeneos del género Chclidogyrus sp, familia Dactylogyridae (28.8%) y del protozoario Trichodina sp (11.0%) (8/73)

    Four Kinds of Hard: An Understanding of Cancer and Death among Latino Community Leaders

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    Early integration of palliative care after a diagnosis of cancer improves outcomes, yet such care for Latino populations is lacking in rural regions of the United States. We used a participatory action research design with Latino community leaders from emerging immigrant communities in North Carolina to explore sociocultural perspectives on cancer and death. Thematic analysis was conceptualized as Four Kinds of Hard represented by four themes: Receiving an Eviction Notice, Getting in the Good Book, Talking is (Sometimes) Taboo, and Seeing Their Pain Makes us Suffer. These themes captured fears of deportation, coping with cancer through faithfulness, ambivalence about advance care planning, and a desire to spare families from suffering. Findings suggest strategies to improve conversations about end-of-life wishes when facing advanced illness and death. This study demonstrates the importance of training Latino community leaders to improve palliative care and bridge service gaps for Latino families living in emerging rural communities.OA publication support through Carolina Consortium agreement with Sag

    Pharmacokinetic/Pharmacodynamic Modeling of Antipyretic and Anti-Inflammatory Effects of Naproxen in the Rat

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    Pharmacokinetic/pharmacodynamic modeling was used to characterize the antipyretic and anti-inflammatory effects of naproxen in rats. An indirect response model was used to describe the antipyretic effects of naproxen after short intravenous infusions. The model assumes that basal temperature (T(a)) is maintained by the balance of fever mediators given by a constant (zero order) rate of synthesis (K(syn)), and a first order rate of degradation (K(out)). After an intraperitoneal injection of lipopolysaccharide, the change in T(a) was modeled assuming an increase in fever mediators described as an input rate function [IR(t)] estimated nonparametrically. An inhibitory E(max) model adequately described the inhibition of IR(t) by naproxen. A more complex model was used to describe the anti-inflammatory response of oral naproxen in the carrageenin-induced edema model. Before carrageenin injection, physiological conditions are maintained by a balance of inflammation mediators given by K(syn) and K(out) (see above). After carrageenin injection, the additional synthesis of mediators is described by IR(t) (see above). Such mediators induced an inflammatory process, which is governed by a first order rate constant (K(IN)) that can be inhibited by the presence of naproxen in plasma. The sigmoidal E(max) model also well described the inhibition of K(IN) by naproxen. Estimates for IC(50) [concentration of naproxen in plasma eliciting half of maximum inhibition of IR(t) or K(IN)] were 4.24 and 4.13 microg/ml, for the antipyretic and anti-inflammatory effects, respectively

    Maintaining RNA integrity in a homogeneous population of mammary epithelial cells isolated by Laser Capture Microdissection

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    Background: Laser-capture microdissection (LCM) that enables the isolation of specific cell populations from complex tissues under morphological control is increasingly used for subsequent gene expression studies in cell biology by methods such as real-time quantitative PCR (qPCR), microarrays and most recently by RNA-sequencing. Challenges are i) to select precisely and efficiently cells of interest and ii) to maintain RNA integrity. The mammary gland which is a complex and heterogeneous tissue, consists of multiple cell types, changing in relative proportion during its development and thus hampering gene expression profiling comparison on whole tissue between physiological stages. During lactation, mammary epithelial cells (MEC) are predominant. However several other cell types, including myoepithelial (MMC) and immune cells are present, making it difficult to precisely determine the specificity of gene expression to the cell type of origin. In this work, an optimized reliable procedure for producing RNA from alveolar epithelial cells isolated from frozen histological sections of lactating goat, sheep and cow mammary glands using an infrared-laser based Arcturus Veritas LCM (Applied Biosystems®) system has been developed. The following steps of the microdissection workflow: cryosectioning, staining, dehydration and harvesting of microdissected cells have been carefully considered and designed to ensure cell capture efficiency without compromising RNA integrity.[br/] Results: The best results were obtained when staining 8 μm-thick sections with Cresyl violet® (Ambion, Applied Biosystems®) and capturing microdissected cells during less than 2 hours before RNA extraction. In addition, particular attention was paid to animal preparation before biopsies or slaughtering (milking) and freezing of tissue blocks which were embedded in a cryoprotective compound before being immersed in isopentane. The amount of RNA thus obtained from ca.150 to 250 acini (300,000 to 600,000 μm2) ranges between 5 to 10 ng. RNA integrity number (RIN) was ca. 8.0 and selectivity of this LCM protocol was demonstrated through qPCR analyses for several alveolar cell specific genes, including LALBA (α-lactalbumin) and CSN1S2 (αs2-casein), as well as Krt14 (cytokeratin 14), CD3e and CD68 which are specific markers of MMC, lymphocytes and macrophages, respectively.[br/] Conclusions: RNAs isolated from MEC in this manner were of very good quality for subsequent linear amplification, thus making it possible to establish a referential gene expression profile of the healthy MEC, a useful platform for tumor biomarker discovery
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