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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
2.
Intrathecal cholecystokinin interacts with morphine but not substance P in modulating the nociceptive flexion reflex in the rat 总被引:6,自引:0,他引:6
The effect of intrathecal (IT) cholecystokinin (CCK), substance P (SP) and morphine (MO) on spinal cord excitability was studied in decerebrate, spinalized rats. CCK had a weaker facilitatory effect on the nociceptive flexion reflex than SP. The possible functional significance of the coexistence of CCK and SP in neurons projecting to the spinal cord was tested by coadministration of the two peptides. At the doses tested no synergistic interaction on the reflex was found with CCK and SP. IT MO caused a brief enhancement followed by a prolonged depression of the reflex. A high dose of CCK injected prior to MO increased the facilitatory effect and decreased the depressive effect of the opiate on the reflex. The effect of desulfated (D) CCK was similar to CCK but at a higher dose. Naloxone (NAL) had a similar effect as CCK when administered prior to MO. The MO-induced depression of the reflex was readily reversed by NAL, but not by CCK. The results indicate that CCK may prevent the inhibitory effect of MO on spinal cord excitability to nociceptive stimulation, but does not reverse it. CCK may alter the balance of excitation-inhibition between various types of dorsal horn interneurons that are involved in the transmission of nociceptive information. 相似文献
3.
Summary The distribution of two seed proteins, namely conglutin and a legumin-like globulin, in developing and mature seeds ofLupinus albus L. has been examined by immunocytochemistry and the concomitant modifications of their constituent polypeptides followed by SDS-PAGE. Both proteins were found within vacuolar protein bodies in various tissues of the cotyledons, although with some differences in the distribution patterns. The legumin-like protein was found to be deposited within the large storage parenchyma cells of the cotyledons in a manner similar to that reported for other storage proteins; little or no immunolabelling was associated with the cotyledonary epidermal and vascular parenchyma cells. In contrast conglutin was present in all cell types.A precursor of the legumin-like protein accumulated transiently in the developing cotyledon, but was subsequently modified by proteolytic cleavage. The onset of such modification was concomitant with a transition in the predominant vacuolar forms within the storage parenchyma cells. No precursor molecules of conglutin have been detected in this study, thus indicating that this protein is deposited in the protein bodies in its mature form.Abbreviations LM
light microscopy
- EM
electron microscopy
- DAF
days after flowering
- SDS-PAGE
sodium dodecyl sulphate polyacrylamide gel electrophoresis
- GAR
goat antirabbit antiserum 相似文献
4.
Sergio Sgorbati Marisa Levi Elio Sparvoli Federica Trezzi Giovanni Lucchini 《Physiologia plantarum》1986,68(3):471-476
Cytometry and flow cytometry were used to study characteristics of fluorescence of the DNA-DAPI complex in nuclei released from different fresh and formaldehyde-fixed pea ( Pisum sativum L. cv. Lincoln) tissues. The two methods of isolation are compared and discussed as well as their possible use for quantitative analysis of DNA in plant tissues. With fixed tissues it is possible to obtain a number of nuclei sufficient for the flow cytometric analysis, even using small amounts of plant tissue. 相似文献
5.
Manju Basu Shu-Ai Weng Hongyu Tang Farhat Khan Federica Rossi Subhash Basu 《Glycoconjugate journal》1996,13(3):423-432
The galactosyltransferase, GalT-4, which catalyses the biosynthesisin vitro of neolactotetraosylceramide, nLcOse4Cer (Gal1-4GleNAc1-3Gal1-4Glc-Cer) from lactotriaosylceramide, LcOse3Cer (GlcNAc1-3Gal1-4Glc-Cer), and UDP-galactose has been purified 107 500-fold from a mineral oil induced mouse T-lyphoma P-1798, using affinity columns. The purified enzyme is partially stabilized in the presence of phospholipid liposomes. Two closely migrating protein bands of apparent molecular weights 56 kDa and 63 kDa were observed after sodium dodecyl sulfate polyacrylamide gel electrophoresis of highly purified mouse GalT-4. These two protein bands, when subjected to limited proteolysis, resulted in three peptides with identical mobilities indicating amino acid sequence identity between the proteins. Both protein bands from P-1798 gave a positive immunostain when tested with polyclonal antibody against bovine lactose synthetase (UDP-Gal:Glc 4-galactosyltransferase) following Western blot analysis on nitrocellulose paper. The enzyme has a pH optimum between 6.5 and 7.0 and like all other galactosyltransferases, GalT-4 has absolute requirements for divalent cation (Mn2+). TheK
m values for the substrate LcOse3Cer and donor UDP-galactose are 110 and 250 µm, respectively. Substrate competition studies with LcOse3Cer and either asialo-agalacto-1-acid glycoprotein orN-acetylglucosamine revealed that these reactions might be catalysed by the same protein. The only other glycolipid which showed acceptor activity toward the purified GalT-4 was iLcOse5Cer (GlcNAc1-1-3Gal1-4Lc3), the precursor for polylactosamine antigens. However, competition studies with these two active substrates using the most purified enzyme fraction, revealed that these two reactions might be catalysed by two different proteins since the experimental values were closer to the theoretical values calculated for two enzymes. Interestingly however, it seems that the GalT-4 from P-1798 has an absolute requirement for anN-acetylglucosamine residue in the substrate since the lyso-derivative (GlcNH21-3Gal1-4Glc-sphingosine) of the acceptor glycolipid LcOse3Cer is completely inactive as substrate while theK
m andV
max of the reacetylated substrate (GlcNac1-3Gal1-4Glc-acetylsphingosine) was comparable with LcOse3Cer. Autoradiography of the radioactive product formed by purified P-1798 GalT-4 confirmed the presence of nLcOse4Cer, as the product cochromatographed with authentic glycolipid. The monoclonal antibody IB-2, specific for nLcOse4Cer, also produced a positive immunostained band on TLC as well as giving a positive ELISA when tested with radioactive product obtained using a highly purified enzyme from mouse P-1798 T-lymphoma.Abbreviations EDTA
ethylenediamine tetraacetate
- ME
-mercaptoethanol
- PEG
polyethylene glycol
- PBS
phosphate buffered saline
- Suc
sucrose
- Mn2+
manganese
- Gal
galactose
- GlcNAc
N-acetylglucosamine
- UDP-Gal
Uridine diphosphate galactose
- Ab
antibody
- SDS
sodium dodecyl sulphate
- PAGE
polyacrylamide gel electrophoresis
- ECB
embryonic chicken brain
- Cer
ceramide
- nLc4 or NlcOse4Cer
Gal1-4GleNac1-3Gal1-4Glc-Cer, neoLactotetraosylceramide
- Lc3 or LcOse3Cer
GlcNac1-3Gal1-4Glc-Cer, lactotriaosylceramide
- iLc5
iLcOse5Cer, GlcNAc1-3nLcOse4Cer
- nLc6
nLcOse6Cer, Gal1-4iLcOse5Cer
- SA–Gal–1AGP
asialo-agalacto1-acid glycoprotein
- TLC
thin layer chromatography 相似文献
6.
Summary Polyclonal antibodies directed against polypeptide epitopes of conglutin , a glycosylated lectin in lupin seed, have been used to identify and quantify this protein in root extracts of germinating lupins. The highest conglutin content was found in protein extracts of root elongation zones after 5 to 7 days germination. Root conglutin showed the same subunit composition, glycosylation pattern, isoelectric point, and lectin activity as the cotyledonary one. Immunolocalization experiments on root thin sections demonstrated that conglutin is chiefly present in the intercellular spaces of the cortical parenchyma, where it forms large aggregates. Labelling of the Golgi complexes and the area between the plasmalemma and cell wall revealed the conglutin pathway from post-synthetic processing to excretion via the secretory system.Abbreviations EDTA
ethylene diamino tetraacetic acid
- IEF
isoelectric focusing
- LRW
London resin white
- NC
nitrocellulose
- PAGE
polyacrylamide gel electrophoresis
- pI
isoelectric point
- Pi
inorganic phosphate
- SDS
sodium dodecylsulphate
- TEM
transmission electron microscopy 相似文献
7.
Federica Rossi Rita Baraldi Osvaldo Facini Bartolomeo Lereari 《Plant Cell, Tissue and Organ Culture》1993,32(2):145-151
The morphogenic effect of different light wavelengths on in vitro rooting of Prunus insititia GF655-2 in relation to the presence of napthaleneacetic acid (NAA) in the culture medium was investigated. Results of experiments in which plantlets were rooted in NAA enriched medium showed that the presence of auxin induced rooting even in the dark after an initial lag period. Illumination of the cultures with Red light was as effective in promoting rooting as treatment with 0.5 M NAA; Red was more active in stimulating rooting in the short term than was NAA. The pattern of root formation resulting from the addition of NAA appeared to dominate development under White, Blue and Far Red treatments. Although it was possible to correlate the rooting response to the phytochrome photoequilibrium induced by the light treatments used, there arises a possible interference of specific Blue absorbing photoreceptors.Abbreviations B
Blue
- FR
Far Red
- HIR
High Irradiance Response
- Pfr
active (far-red absorbing) form of phytochrome
- Ptot
total phytochrome
- R
Red
- W
White
- NAA
-naphtaleneacetic acid
- BA
benzyladenine
- IAA
indole 3-acetic acid 相似文献
8.
Francesca Vittoria Sbrana Benedetta Fiordi Jessica Bordini Daniela Belloni Federica Barbaglio Luca Russo Lydia Scarfò Paolo Ghia Cristina Scielzo 《Journal of cellular and molecular medicine》2023,27(4):576-586
Chronic Lymphocytic Leukaemia (CLL) is the most common adult B-cell leukaemia and despite improvement in patients' outcome, following the use of targeted therapies, it remains incurable. CLL supportive microenvironment plays a key role in both CLL progression and drug resistance through signals that can be sensed by the main components of the focal adhesion complex, such as FAK and PYK2 kinases. Dysregulations of both kinases have been observed in several metastatic cancers, but their role in haematological malignancies is still poorly defined. We characterized FAK and PYK2 expression and observed that PYK2 expression is higher in leukaemic B cells and its overexpression significantly correlates with their malignant transformation. When targeting both FAK and PYK2 with the specific inhibitor defactinib, we observed a dose–response effect on CLL cells viability and survival. In vivo treatment of a CLL mouse model showed a decrease of the leukaemic clone in all the lymphoid organs along with a significant reduction of macrophages and of the spleen weight and size. Our results first define a possible prognostic value for PYK2 in CLL, and show that both FAK and PYK2 might become putative targets for both CLL and its microenvironment (e.g. macrophages), thus paving the way to an innovative therapeutic strategy. 相似文献
9.
Francesca Gherardi Federica Tarducci Marco Vannini 《Ethology : formerly Zeitschrift fur Tierpsychologie》1988,77(4):300-316
Locomotor activity in a field population of the freshwater crab, Potamon fluviatile, was studied during the breeding season by means of radio-telemetry and by direct counts of active animals along a transect of the stream. The basic pattern of crabs' locomotor activity can be described as a sequence of short distance movements around the shelters (foraging movements), followed by rarer long distance displacements (wandering movements). Whilst direct counting showed that the crabs exhibit a broadly nocturnal rhythm in foraging movements, no daily periodicity in wandering activity was revealed by telemetry. There is sexual difference in these latter excursions: females move farther along the stream and into the surrounding terrestrial habitat than do males. This behaviour is in contrast to observations made during the non-breeding season and is probably related to the stage of female reproduction. 相似文献
10.
Margherita Sosio Giuseppe Amati Carmela Cappellano Edoardo Sarubbi Federica Monti Stefano Donadio 《Molecular microbiology》1996,22(1):43-51
SecA protein, the ATPase promoting translocation of proteins across the Escherichia coli inner membrane, contains two ATP-binding domains that differ greatly in their affinity for bound nucleotide. In order to define more precisely the location of the high-affinity nucleotide-binding site, oligonucleotide-directed mutagenesis was used to introduce cysteine residues into the SecA sequence, and a cysteine-specific cleavage reagent was employed to generate defined peptides of SecA protein after photocross-linking with [α-32P]-ATP. This analysis revealed that the nucleotide was cross-linked between amino acid residues 75 and 97 of SecA protein. The biochemical function of the high affinity ATP-binding domain was explored by subcellular fractionation studies which demonstrated that SecA proteins defective in this region were found almost exclusively in their integral membrane form, while SecA proteins with defects in the low-affinity ATP-domain showed a normal distribution of cytosolic, peripheral and integral membrane forms. Interestingly, the SecA51(Ts) protein that has a Leu to Pro substitution at amino acid residue 43 bound ATP with high affinity, but its fractionation pattern and translocation ATPase activity were similar to those of proteins with defects in the high-affinity ATP-binding site. These results delimit more precisely the high-affinity ATP-binding domain of SecA, indicate the importance of the early amino-terminal region of SecA protein in the functioning of this domain, and demonstrate the role of this domain in regulating penetration of SecA protein into the inner membrane. Our results lead to a simple model for the regulation of a cycle of SecA insertion into, and de-insertion from, the inner membrane by the activity of the high-affinity ATP-binding domain. 相似文献