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31.
Linda Hernndez Duran David Thomas Wilson Mark Briffa Tasmin Lee Rymer 《Ecology and evolution》2021,11(7):2974
Spiders are useful models for testing different hypotheses and methodologies relating to animal personality and behavioral syndromes because they show a range of behavioral types and unique physiological traits (e.g., silk and venom) that are not observed in many other animals. These characteristics allow for a unique understanding of how physiology, behavioral plasticity, and personality interact across different contexts to affect spider''s individual fitness and survival. However, the relative effect of extrinsic factors on physiological traits (silk, venom, and neurohormones) that play an important role in spider survival, and which may impact personality, has received less attention. The goal of this review is to explore how the environment, experience, ontogeny, and physiology interact to affect spider personality types across different contexts. We highlight physiological traits, such as neurohormones, and unique spider biochemical weapons, namely silks and venoms, to explore how the use of these traits might, or might not, be constrained or limited by particular behavioral types. We argue that, to develop a comprehensive understanding of the flexibility and persistence of specific behavioral types in spiders, it is necessary to incorporate these underlying mechanisms into a synthesized whole, alongside other extrinsic and intrinsic factors. 相似文献
32.
Manuel Ferrer Francisco J. Plou Gloria Fuentes M. Angeles Cruces Lotte Andersen Ole Kirk 《Biocatalysis and Biotransformation》2013,31(1):63-71
Lipase from Thermomyces lanuginosus (formerly Humicola lanuginosa ) was immobilized using granulation by incubating low-particle-size silica with the lipase. Granules with a particle diameter in the range 0.3-1 u mm were obtained. The immobilized lipase was tested in the acylation of sucrose with vinyl laurate in mixtures of tert -amyl alcohol: dimethyl sulfoxide. Results were compared with immobilization of enzyme by adsorption on polypropylene (Accurel EP100), deposition on Celite by precipitation, and covalent attachment to Eupergit C. Granulated lipase converted >95% of sucrose into 6- O -lauroylsucrose in 6 u h. Accurel-lipase was also very active, converting 70% of sucrose into monoester in 2 u h. The residual activity of granules after five reaction cycles under the best reaction conditions was 72%; this value was considerably higher than the one observed for the same lipase adsorbed on Accurel (15% residual activity after five cycles). 相似文献
33.
Marli Dercksen Gerhard Koekemoer Marinus Duran Ronald J. A. Wanders Lodewyk J. Mienie Carolus J. Reinecke 《Metabolomics : Official journal of the Metabolomic Society》2013,9(4):765-777
Isovaleric acidemia (IVA, MIM 248600) can be a severe and potentially life-threatening disease in affected neonates, but with a positive prognosis on treatment for some phenotypes. This study presents the first application of metabolomics to evaluate the metabolite profiles derived from urine samples of untreated and treated IVA patients as well as of obligate heterozygotes. All IVA patients carried the same homozygous c.367 G > A nucleotide change in exon 4 of the IVD gene but manifested phenotypic diversity. Concurrent class analysis (CONCA) was used to compare all the metabolites from the original complete data set obtained from the three case and two control groups used in this investigation. This application of CONCA has not been reported previously, and is used here to compare four different modes of scaling of all metabolites. The variables important in discrimination from the CONCA thus enabled the recognition of different metabolic patterns encapsulated within the data sets that would not have been revealed by using only one mode of scaling. Application of multivariate and univariate analyses disclosed 11 important metabolites that distinguished untreated IVA from controls. These included well-established diagnostic biomarkers of IVA, endogenous detoxification markers, and 3-hydroxycaproic acid, an indicator of ketosis, but not reported previously for this disease. Nine metabolites were identified that reflected the effect of treatment of IVA. They included detoxification products and indicators related to the high carbohydrate and low protein diet which formed the hallmark of the treatment. This investigation also provides the first comparative metabolite profile for heterozygotes of this inherited metabolic disorder. The detection of informative metabolites in even very low concentrations in all three experimental groups highlights the potential advantage of the holistic mode of analysis of inherited metabolic diseases in a metabolomics investigation. 相似文献
34.
Flood Peter J. Duran Alain Barton Mark Mercado-Molina Alex E. Trexler Joel C. 《Hydrobiologia》2020,847(7):1571-1586
Hydrobiologia - Non-native species can simultaneously affect ecological structures, functions, and services of the invaded ecosystem. In this paper, we report that the study of non-native... 相似文献
35.
Jorge Soriano María García-Díaz Margarita Mora Maria Lluïsa Sagristá Santi Nonell Angeles Villanueva Juan Carlos Stockert Magdalena Cañete 《Biochimica et Biophysica Acta (BBA)/General Subjects》2013
Background
The cell death pathway activated after photodynamic therapy (PDT) is controlled by a variety of parameters including the chemical structure of the photosensitizer, its subcellular localization, and the photodynamic damage induced. The present study aims to characterize a suitable m-THPPo liposomal formulation, to determine its subcellular localization in HeLa cells and to establish the cell death mechanisms that are activated after photodynamic treatments.Methods
Liposomes containing m-THPPo were prepared from a mixture of DPPC and DMPG at a 9:1 molar ratio. In order to procure the best encapsulation efficiency, the m-THPPo/lipid molar ratio was considered. HeLa cells were incubated with liposomal m-THPPo and the subcellular localization of m-THPPo was studied. Several assays such as TUNEL, annexin V/propidium iodide and Hoechst-33258 staining were performed after photodynamic treatments. The apoptotic initiation was assessed by cytochrome c and caspase-2 immunofluorescence.Results
m-THPPo encapsulated in liposomes showed a decrease of the fluorescence and singlet oxygen quantum yields, compared to those of m-THPPo dissolved in tetrahydrofuran. Liposomal m-THPPo showed colocalization with LysoTracker® and it induced photoinactivation of HeLa cells by an apoptotic mechanism. In apoptotic cells no relocalization of cytochrome c could be detected, but caspase-2 was positive immediately after photosensitizing treatments.Conclusions
Photodynamic treatment with liposomal m-THPPo leads to a significant percentage of apoptotic morphology of HeLa cells. The activation of caspase-2, without the relocalization of cytochrome c, indicates a mitochondrial-independent apoptotic mechanism.General significance
These results provide a better understanding of the cell death mechanism induced after liposomal m-THPPo photodynamic treatment. 相似文献36.
37.
Hansel Gómez Mae Chappé Pedro A Valiente Tirso Pons María de Los Angeles Chávez Jean-Louis Charli Isel Pascual 《Journal of biosciences》2013,38(3):461-469
Dipeptidyl peptidase IV (DPP-IV) is an ectopeptidase with many roles, and a target of therapies for different pathologies. Zinc and calcium produce mixed inhibition of porcine DPP-IV activity. To investigate whether these results may be generalized to mammalian DPP-IV orthologues, we purified the intact membrane-bound form from rat kidney. Rat DPP-IV hydrolysed Gly-Pro-p-nitroanilide with an average Vmax of 0.86±0.01 μmol min–1mL–1 and KM of 76±6 μM. The enzyme was inhibited by the DPP-IV family inhibitor l-threo-Ile-thiazolidide (Ki=64.0±0.53 nM), competitively inhibited by bacitracin (Ki=0.16±0.01 mM) and bestatin (Ki=0.23±0.02 mM), and irreversibly inhibited by TLCK (IC50 value of 1.20±0.11 mM). The enzyme was also inhibited by divalent ions like Zn2+ and Ca2+, for which a mixed inhibition mechanism was observed (Ki values of the competitive component: 0.15±0.01 mM and 50.0±1.05 mM, respectively). According to bioinformatic tools, Ca2+ ions preferentially bound to the β-propeller domain of the rat and human enzymes, while Zn2+ ions to the α-β hydrolase domain; the binding sites were essentially the same that were previously reported for the porcine DPP-IV. These data suggest that the cationic susceptibility of mammalian DPP-IV orthologues involves conserved mechanisms. 相似文献
38.
Virginia Souza-Egipsy Angeles Aguilera Eva Mateo-Martí José Angel Martín-Gago Ricardo Amils 《Geomicrobiology journal》2013,30(8):692-706
This study examines fossil microorganisms found in iron-rich deposits in an extreme acidic environment, the Tinto River in SW Spain. Both electron microscopy (SEM and TEM) and non-destructive in situ microanalytical techniques (EDS, EMP and XPS) were used to determine the role of permineralization and encrustation in preserving microorganisms forming biofilms in the sediments. Unicellular algae were preserved by silica permineralization of their cell walls. Bacterial biofilms were preserved as molds by epicellular deposition of schwertmannite around them. In the case of fungi and filamentous algae, we observed permineralization of cell structures by schwertmannite in the sediments. The extracellular polymeric matrix around the cells was also preserved through permineralization of the fibrillar component. The process of permineralization and deposition of iron-rich precipitates present in the acidic waters of Rio Tinto served to preserve many microfossils in an oxidizing environment, in which organic compounds would not normally be expected to persist. Studies of microbial fossil formation mechanisms in modern extreme environments should focus on defining criteria to identify inorganic traces of microbial life in past environments on Earth or other planets. 相似文献
39.
Zaida Araujo Francesca Giampietro María de los Angeles Bochichio Andrea Palacios Jenifer Dinis Jaime Isern Jacobus Henry de Waard Elsa Rada Rafael Borges Carlos Fernández de Larrea Angel Villasmil Magnolia Vanegas Jose Antonio Enciso-Moreno Manuel Alfonso Patarroyo 《Memórias do Instituto Oswaldo Cruz》2013,108(2):131-139
The goal of this study was to demonstrate the usefulness of an enzyme-linked immunosorbent assay (ELISA) for the serodiagnosis of pulmonary tuberculosis (PTB) and extrapulmonary TB (EPTB). This assay used 20 amino acid-long, non-overlapped synthetic peptides that spanned the complete Mycobacterium tuberculosis ESAT-6 and Ag85A sequences. The validation cohort consisted of 1,102 individuals who were grouped into the following five diagnostic groups: 455 patients with PTB, 60 patients with EPTB, 40 individuals with non-EPTB, 33 individuals with leprosy and 514 healthy controls. For the PTB group, two ESAT-6 peptides (12033 and 12034) had the highest sensitivity levels of 96.9% and 96.2%, respectively, and an Ag85A-peptide (29878) was the most specific (97.4%) in the PTB groups. For the EPTB group, two Ag85A peptides (11005 and 11006) were observed to have a sensitivity of 98.3% and an Ag85A-peptide (29878) was also the most specific (96.4%). When combinations of peptides were used, such as 12033 and 12034 or 11005 and 11006, 99.5% and 100% sensitivities in the PTB and EPTB groups were observed, respectively. In conclusion, for a cohort that consists entirely of individuals from Venezuela, a multi-antigen immunoassay using highly sensitive ESAT-6 and Ag85A peptides alone and in combination could be used to more rapidly diagnose PTB and EPTB infection. 相似文献
40.
María de los Angeles Ribas Antúnez Blanca Girón Iraima Monsalvez Luis Morier Gretel Acosta Yahisel Tejero Yanislet Cordero Dainelyd Piedra 《Memórias do Instituto Oswaldo Cruz》2013,108(2):255-256
Rabies is a neurotropic disease that is often lethal. The early diagnosis of rabies infection is important and requires methods that allow for the isolation of the virus from animals and humans. The present study compared a modified shell vial (MSV) procedure using 24-well tissue culture plates with the mouse inoculation test (MIT), which is considered the gold standard for rabies virus isolation. Thirty brain samples (25 positive and 5 negative by the fluorescent antibody test) obtained from different animal species at the National Institute of Hygiene Rafael Rangel in Caracas, Venezuela, were studied by the MIT and MSV assays. Nine samples (36%) were positive at 24 h, 10 (40%) were positive at 48 h and six (24%) were positive at 72 h by the MSV assay. With the MIT assay, 76% were positive at six days post inoculation and 12% were positive at 12 and 18 days post inoculation. One sample that was negative according to the MSV assay was positive with MIT on the 12th day. The MSV procedure exhibited a sensitivity of 96.2%, a specificity of 100%, a positive predictive value of 100% and a negative predictive value 80%. This procedure allowed for rapid rabies virus detection. MIT can be employed as an alternative method in laboratories without tissue culture facilities. 相似文献