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441.
Esperanza González-Rojano Julio Marcotegui Leonor Laredo Luther Gwaza John Gordon Antonio Portolés Emilio Vargas Susana Morales-Alcelay Alfredo García-Arieta 《Chirality》2020,32(9):1169-1177
According to the Ibuprofen Product-Specific Bioequivalence Guidance of the European Medicines Agency, achiral bioanalytical methods are considered acceptable for demonstration of bioequivalence of ibuprofen-containing products. The aim of this investigation is to compare the bioequivalence outcomes obtained with individual R and S ibuprofen enantiomers and the sum of both enantiomers from bioequivalence studies in which new intravenous ibuprofen products were compared with oral ibuprofen products. Bioequivalence was assessed for S and R enantiomers of ibuprofen and the sum of both enantiomers, which was calculated to represent the results that would have been obtained with an achiral assay. The infusion rates of 15, 20, and 30 minutes modify the maximum concentration (Cmax) of the intravenous administrations. In contrast, the time when the maximum concentration is observed (Tmax) was insensitive to detect differences in input rate within this range of infusion times. The eutomer S-ibuprofen is the least sensitive analyte to detect differences in input rate; therefore, the regulatory acceptance of achiral bioanalytical methods for ibuprofen bioequivalence studies is justified because the sum of both enantiomers is more discriminative than the chiral methods where only the eutomer is used for regulatory decisions. 相似文献
442.
Free-living amoebae are widely distributed in aquatic environments and their hygienic, medical and ecological relationships to man are increasingly important. The purpose of this study was to isolate free-living amoebae from water-hyacinth root (Eichhornia crassipes) and the water of an urban lake in Mexico City. Five grams of wet root were seeded on non-nutritive agar with Enterobacter aerogenes (NNE). Water samples were concentrated by centrifugation at 1200g for 15 min and the pellet was seeded on NNE. Of the 16 isolated genera, 10 were detected in both habitats. The most frequent were Vannella in root and Acanthamoeba and Naegleria in water. The total number of isolates and genera isolated from root was higher than that isolated from water. The differences between root and water are probably due to the morphological characteristics of water-hyacinth root, which provides a large habitat and refuge area for many organisms. 相似文献
443.
Maria Glria Teixeira Lacita Menezes Skalinski Enny S. Paixo Maria da Conceio N. Costa Florisneide Rodrigues Barreto Gubio Soares Campos Silvia Ines Sardi Rejane Hughes Carvalho Marcio Natividade Martha Itaparica Juarez Pereira Dias Soraya Castro Trindade Brbara Pereira Teixeira Vanessa Morato Eloisa Bahia Santana Cristina Borges Goes Neuza Santos de Jesus Silva Carlos Antonio de Souza Teles Santos Laura C. Rodrigues Jimmy Whitworth 《PLoS neglected tropical diseases》2021,15(4)
BackgroundChikungunya is an arbovirus, transmitted by Aedes mosquitoes, which emerged in the Americas in 2013 and spread rapidly to almost every country on this continent. In Brazil, where the first cases were detected in 2014, it currently has reached all regions of this country and more than 900,000 cases were reported. The clinical spectrum of chikungunya ranges from an acute self-limiting form to disabling chronic forms. The purpose of this study was to estimate the seroprevalence of chikungunya infection in a large Brazilian city and investigate the association between viral circulation and living condition.Methodology/principal findingsWe conducted a population-based ecological study in selected Sentinel Areas (SA) through household interviews and a serologic survey in 2016/2017. The sample was of 1,981 individuals randomly selected. The CHIKV seroprevalence was 22.1% (17.1 IgG, 2.3 IgM, and 1.4 IgG and IgM) and varied between SA from 2.0% to 70.5%. The seroprevalence was significantly lower in SA with high living conditions compared to SA with low living condition. There was a positive association between CHIKV seroprevalence and population density (r = 0.2389; p = 0.02033).Conclusions/significanceThe seroprevalence in this city was 2.6 times lower than the 57% observed in a study conducted in the epicentre of the CHIKV epidemic of this same urban centre. So, the herd immunity in this general population, after four years of circulation of this agent is relatively low. It indicates that CHIKV transmission may persist in that city, either in endemic form or in the form of a new epidemic, because the vector infestation is persistent. Besides, the significantly lower seroprevalences in SA of higher Living Condition suggest that beyond the surveillance of the disease, vector control and specific actions of basic sanitation, the reduction of the incidence of this infection also depends on the improvement of the general living conditions of the population. 相似文献
444.
This contribution discusses the interatheriids from Quebrada Fiera, a Late Oligocene locality in the south of Mendoza Province. In addition, the taxonomic status of the Deseadan interatheres Plagiarthrus clivus, Argyrohyrax proavus, Argyrohyrax proavunculus, ?Argyrohyrax acuticostatus, Progaleopithecus fissurelatus, Progaleopithecus tournoueri, and Notohyrax conicus is discussed. We recognise in Quebrada Fiera A. proavus and Progaleopithecus sp. A possible third taxon is represented by one specimen that shows a combination of features that do not permit accurate assignment. These new remains, in combination with a systematic study of Deseadan interatheres, allow for a better definition of each recognised taxon, extended diagnoses, and clarification of some long-standing taxonomic misconceptions. Indeed, the priority of A. proavus over P. clivus is established, and the latter is proposed as a nomen dubium. Associated deciduous and permanent dentition and some limb bones provide new data on the ontogenetic variation and postcranial morphology of Argyrohyrax. Phylogenetic analysis supports the taxonomic determinations and places A. proavus in a basal position with respect to Archaeophylus or Progaleopithecus. Documented fossil records of Argyrohyrax and Progaleopithecus in Mendoza extend the known range to middle latitudes in central west Argentina; these taxa expand the list of mammals from Quebrada Fiera with Patagonian affinities. 相似文献
445.
Abdul Majid Khan Esperanza Cerdeño Muhammad Akbar Khan Muhammad Akhtar 《Annales de Paléontologie》2013
Unpublished rhinocerotid remains from the Lower and Middle Siwaliks of Pakistan are described in this paper and recognized as two species of Alicornops. Alicornops complanatum (Heissig) is identified in the Dhok Pathan Formation of the Middle Siwaliks and Alicornops laogouense Deng in the Kamlial Formation of the Lower Siwaliks. The Dhok Pathan Formation levels with A. complanatum are roughly correlated with the late Miocene-Pliocene European mammal zones MN10-15. In turn, levels with A. laogouense of the Kamlial Formation would correlate with the middle–late Aragonian (middle Miocene) European MN5. The recognition of the Chinese species A. laogouense in the Potwar Plateau represents the first discovery of this taxon in Pakistan and increases the geographical and stratigraphic distributions of this species, and adds to the rhinocerotid association from the Siwaliks. In turn, the presence of A. complanatum in the Siwaliks of Potwar Plateau also enlarges its geographic distribution in Pakistan, as it was previously known from the Bugti Hills of Balouchistan. The absence of Alicornops from the Siwaliks in the Chinji and Nagri formations (between late MN5 and MN9 zones) might be due to an inadequate fossil record, as other rhinocerotid species are known from Kamlial to Dhok Pathan formations. However, the two recorded species of Alicornops could also reveal two independent migration waves as supported by the appearance of other taxa in different formations. A summary of fossil Cenozoic rhinocerotids from different areas of Pakistan is also presented. 相似文献
446.
María Isabel González-Siso Alba Touri?o ángel Vizoso ángel Pereira-Rodríguez Esther Rodríguez-Belmonte Manuel Becerra María Esperanza Cerdán 《Microbial biotechnology》2015,8(2):319-330
In this paper, we report the metabolic engineering of the respiratory yeast Kluyveromyces lactis by construction and characterization of a null mutant (Δklndi1) in the single gene encoding a mitochondrial alternative internal dehydrogenase. Isolated mitochondria of the Δklndi1 mutant show unaffected rate of oxidation of exogenous NADH, but no oxidation of matrix NADH; this confirms that KlNdi1p is the only internal NADH dehydrogenase in K. lactis mitochondria. Permeabilized cells of the Δklndi1 mutant do not show oxidation of matrix NADH, which suggests that shuttle systems to transfer the NADH from mitochondrial matrix to cytosol, for being oxidized by external dehydrogenases, are not functional. The Δklndi1 mutation decreases the chronological life span in absence of nutrients. The expression of KlNDI1 is increased by glutathione reductase depletion. The Δklndi1 mutation shifts the K. lactis metabolism from respiratory to fermentative: the Δklndi1 strain shows reduced respiration rate and increased ethanol production from glucose, while it does not grow in non-fermentable carbon sources such as lactate. The biotechnological benefit of the Δklndi1 mutant for bioethanol production from waste cheese whey lactose was proved. 相似文献
447.
Mariana Ferreira-Duarte Tiago Rodrigues-Pinto Daniela Menezes-Pinto Marisa Esteves-Monteiro Salom Gonalves-Monteiro Sara Capas-Peneda Fernando Magro Patrícia Dias-Pereira Manuela Morato Margarida Duarte-Araújo 《Experimental Animals》2021,70(2):245
Reproducibility in animal research is crucial for its reliance and translational relevance. The 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced model of inflammatory bowel disease (IBD) is widely used but inconsistently and incompletely characterized throughout the literature. This hinders comparisons between studies and influences the low rate of translation of effective preclinical molecules. The purpose of this study was to categorize TNBS-induced colitis, based on macroscopic and microscopic scoring systems, and to identify basic routine parameters that could anticipate those categories. We retrospectively analysed male Wistar Rattus norvegicus (n=28 for the control group and n=87 for the TNBS group) and categorized TNBS-induced colitis in three phenotypes: Mild, Moderate and Severe colitis, as for human IBD. Also, we showed that the time course of food intake and fecal excretion (but not body weight, fluid intake or welfare scores) could foresee those categories. So, routine evaluation of food intake and fecal excretion may guide researchers in planning their experiments, selecting the animals with the severity of colitis that better matches their aims, or applying early humane endpoints to animals that will not be used in the experiments. In conclusion, categorizing TNBS-induced colitis enhances the reproducibility of data gathered with this experimental model and strengths its translational relevance. 相似文献
448.