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1.
It has long been debated whether the mind consists of specialized and independently evolving modules, or whether and to what extent a general factor accounts for the variance in performance across different cognitive domains. In this study, we used a hierarchical Bayesian model to re-analyse individual level data collected on seven primate species (chimpanzees, bonobos, orangutans, gorillas, spider monkeys, brown capuchin monkeys and long-tailed macaques) across 17 tasks within four domains (inhibition, memory, transposition and support). Our modelling approach evidenced the existence of both a domain-specific factor and a species factor, each accounting for the same amount (17%) of the observed variance. In contrast, inter-individual differences played a minimal role. These results support the hypothesis that the mind of primates is (at least partially) modular, with domain-specific cognitive skills undergoing different evolutionary pressures in different species in response to specific ecological and social demands. 相似文献
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Calcitonin gene-related peptide (CGRP) receptor activity was studied in WE-68 human Ewing's sarcoma cells. 125I-human CGRP bound in a time-dependent, reversible and saturable manner. Scatchard plots were compatible with the presence of a homogenous population of CGRP receptors with high affinity (Kd = 15 pM, and Bmax = 1.9 fmol/mg protein). The potency order of unlabeled peptides in the presence of radioligand, was: human CGRP-II greater than human CGRP = chick CGRP greater than rat CGRP = rat [Tyr0]CGRP greater than human [Tyr0] CGRP much greater than salmon calcitonin (CT) greater than rat [Tyr0]CGRP-(28-37). Each peptide except CT and [Tyr0]CGRP-(28-37) stimulated cyclic AMP generation in a concentration-dependent manner, and the relative potencies paralleled their relative ability in inhibiting 125I-human CGRP binding. We conclude that WE-68 Ewing's sarcoma cells express genuine CGRP receptors which upon activation lead to stimulation of cyclic AMP formation 相似文献
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Hydroxamate-Stimulated O(2) Uptake in Roots of Pisum sativum and Zea mays, Mediated by a Peroxidase : Its Consequences for Respiration Measurements 总被引:4,自引:4,他引:0 下载免费PDF全文
Low concentrations of salicylhydroxamic acid (<5 millimolar) stimulate O2 uptake in intact roots of Pisum sativum. We demonstrate that the hydroxamate-stimulated O2 uptake does not reside in the mitochondria. We also show that the hydroxamate-stimulated O2 uptake is due to the activation of a peroxidase catalyzing reduction of O2. This peroxidase, which can use both NADH and NADPH as a substrate, is stimulated by low concentrations of monophenols, e.g. salicylhydroxamic acid and 2-methoxyphenol. It is inhibited by high (20 millimolar) concentrations of salicylhydroxamic acid, cyanide, and scavengers of the superoxide free radical ion, e.g. ascorbate, gentisic acid, and catechol. In the presence of gentisic acid, O2 uptake by intact pea roots was no longer stimulated by low concentrations of salicylhydroxamic acid. The consequence of the present finding for in vivo respiration measurements is that the use of low concentrations of salicylhydroxamic acid and uncoupler is reliable only in the presence of a suitable superoxide free radical scavenger which prevents activation of the peroxidase. It also confirms that high concentrations of salicylhydroxamic acid (20-25 millimolar) can be safely used in short-term experiments to assess the activity of the alternative path in intact roots. 相似文献
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PurposeTP53, encoding the protein p53, is among the most frequently mutated genes in all cancers. A high frequency of 60 – 90% mutations is seen in esophageal squamous cell carcinoma (ESCC) patients. Certain p53 mutants show gain-of-function (GoF) oncogenic features unrelated to its wild type functions.MethodsThis study functionally characterized a panel of p53 mutants in individual ESCC cell lines and assayed for GoF oncogenic properties.ResultsThe ESCC cell line with endogenous p53R248Q expression showed suppressed tumor growth in an immunocompromised mouse model and suppressed colony growth in in vitro three-dimensional culture, when depleted of the endogenous p53 protein expression. This suppression is accompanied by suppressed cell cycle progression, along with reduced integrin expression and decreased focal adhesion kinase and extracellular-regulated protein kinase signaling and can be compensated by expression of a constitutively active mitogen-activated protein. P53R248Q enhances cell proliferation upon glutamine deprivation, as compared to other non-GoF mutants.ConclusionsIn summary, study of the functional contributions of endogenous p53 mutants identified a novel GoF mechanism through which a specific p53 mutant exerts oncogenic features and contributes to ESCC tumorigenesis. 相似文献
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Surfactant protein-A (SP-A) belongs to a family of collagen-containing C-type lectins called collectins. SP-A is expressed by renal tubule epithelial cells. We investigated the distribution of SP-A in renal cell carcinomas (RCC) using immunohistochemical techniques and western blotting. We used 35 formalin fixed, paraffin embedded (FFPE) RCC tissue samples. We compared results with clinico-pathological parameters of RCC including age, sex, Fuhrman grade, tumor volume, tumor node metastasis (TNM) and clinical stage. SP-A was localized in the glomerulus and renal tubule epithelium in nontumor tissue and strong SP-A immunoreactivity was observed in tumor tissue. SP-A was expressed in the RCC tumor cells (64%) and nontumor cells (34%) in males and RCC tumor cells (90%) and nontumor cells (30%) in females. There was a significant correlation between SP-A immunoreactivity in tumor cells and gender, age, tumor diameter, Fuhrman grade and tumor diameter. Western blot analysis supported the immunohistochemical findings. We present evidence for involvement of SP-A in RCC and suggest that increased SP-A expression in RCC is associated with favorable prognosis. 相似文献
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Ricardo Moreira Borges Samuel Santos Valença Alan Aguiar Lopes Nancy dos Santos Barbi Antonio Jorge Ribeiro da Silva 《Phytochemistry letters》2013,6(1):96-100
Five triterpenoidal saponins were isolated from the roots of Chiococca alba (L.) Hitchc. (Rubiaceae). Two of the saponins, chiococcasaponin III (3-O-β-d-glucopyranurosyl-3β-hydroxyolean-12,15-dien-28-oic acid 28-O-β-d-xylopyranosyl (1 → 4)-α-l-rhamnopyranosyl (1 → 2)-α-l-arabinopyranosyl ester) and chiococcasaponin IV (3-O-β-d-glucopyranurosyl-3β-hydroxyolean-12,15-dien-28-oic acid 28-O-α-l-rhamnopyranosyl (1 → 2)-α-l-arabinopyranosyl ester) were new and their structures were elucidated on the basis of extensive application of NMR techniques and high resolution electrospray mass spectrometry together with acid hydrolysis product analysis. As part of our investigations on the chemical profile and pharmacological activity of the roots of C. alba, we report the results of the evaluation of the activity of the saponin fractions against in vitro lipopolysaccharide-induced inflammation. The results found, strongly support the fractions I, III and IV as having anti-inflammatory properties. 相似文献
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In a three-hour bioassay, we tested the palatability and feeding preferences of Uresiphita maorialis (kōwhai moth) for Sophora tetraptera, Sophora microphylla and Sophora prostrata. Palatability tests showed no differences among the Sophora species. Feeding preferences, on the other hand, showed that S. tetraptera and S. microphylla leaves are preferred over S. prostrata leaves. Our results support our field observations in Wellington city parks and gardens showing that S. tetraptera and S. microphylla plants frequently have higher densities of larvae than S. prostrata. 相似文献
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Emilay B.T. Diogo Gleiston G. Dias Bernardo L. Rodrigues Tiago T. Guimarães Wagner O. Valença Celso A. Camara Ronaldo N. de Oliveira Mauro G. da Silva Vitor F. Ferreira Yen Galdino de Paiva Marilia O.F. Goulart Rubem F.S. Menna-Barreto Solange L. de Castro Eufrânio N. da Silva Júnior 《Bioorganic & medicinal chemistry》2013,21(21):6337-6348
In our continued search for novel trypanocidal compounds, twenty-six derivatives of para- and ortho-naphthoquinones coupled to 1,2,3-triazoles were synthesized. These compounds were evaluated against the infective bloodstream form of Trypanosoma cruzi, the etiological agent of Chagas disease. Compounds 17–24, 28–30 and 36–38 are described herein for the first time. Three of these novel compounds (28–30) were found to be more potent than the standard drug benznidazole, with IC50/24 h values between 6.8 and 80.8 μM. Analysis of the toxicity to heart muscle cells led to LC50/24 h of <125, 63.1 and 281.6 μM for 28, 29 and 30, respectively. Displaying a selectivity index of 34.3, compound 30 will be further evaluated in vivo. The electrochemical properties of selected compounds were evaluated in an attempt to find correlations with trypanocidal activity, and it was observed that more electrophilic quinones were generally more potent. 相似文献