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101.
102.
Infant facial features are thought to be powerful elicitors of caregiving behaviour. It has been widely assumed that men and women respond in different ways to those features, such as a large forehead and eyes and round protruding cheeks, colloquially described as 'cute'. We investigated experimentally potential differences using measures of both conscious appraisal ('liking') and behavioural responsivity ('wanting') to real world infant and adult faces in 71 non-parents. Overall, women gave significantly higher 'liking' ratings for infant faces (but not adult faces) compared to men. However, this difference was not seen in the 'wanting' task, where we measured the willingness of men and women to key-press to increase or decrease viewing duration of an infant face. Further analysis of sensitivity to cuteness, categorising infants by degree of infantile features, revealed that both men and women showed a graded significant increase in both positive attractiveness ratings and viewing times to the 'cutest' infants. We suggest that infant faces may have similar motivational salience to men and women, despite gender idiosyncrasies in their conscious appraisal. 相似文献
103.
Rusling DA Powers VE Ranasinghe RT Wang Y Osborne SD Brown T Fox KR 《Nucleic acids research》2005,33(9):3025-3032
We have achieved recognition of all 4 bp by triple helix formation at physiological pH, using triplex-forming oligonucleotides that contain four different synthetic nucleotides. BAU [2′-aminoethoxy-5-(3-aminoprop-1-ynyl)uridine] recognizes AT base pairs with high affinity, MeP (3-methyl-2 aminopyridine) binds to GC at higher pHs than cytosine, while APP (6-(3-aminopropyl)-7-methyl-3H-pyrrolo[2,3-d]pyrimidin-2(7H)-one) and S [N-(4-(3-acetamidophenyl)thiazol-2-yl-acetamide)] bind to CG and TA base pairs, respectively. Fluorescence melting and DNase I footprinting demonstrate successful triplex formation at a 19mer oligopurine sequence that contains two CG and two TA interruptions. The complexes are pH dependent, but are still stable at pH 7.0. BAU, MeP and APP retain considerable selectivity, and single base pair changes opposite these residues cause a large reduction in affinity. In contrast, S is less selective and tolerates CG pairs as well as TA. 相似文献
104.
Serotonin (5-HT) is an ancient chemical that plays a crucial functional role in almost every living organism. It regulates
platelet aggregation, activation of immune cells, and contraction of stomach and intestinal muscles. In addition, serotonin
acts as a neurotransmitter in the brain and the peripheral nervous system. These activities are initiated by the binding of
serotonin to 15 or more receptors that are pharmacologically classified into seven groups, 5-HT1 through 5-HT7. Each group is further divided into subgroups of receptors that are homologous but are encoded by discrete genes. With the
exception of the 5-HT3 receptor-a cation channel—all of the others are G protein-coupled receptors that potentially activate or inhibit a large
number of biochemical cascades. This review will endeavor to compare and contrast such signaling pathways with special attention
to their tissue-specific occurrence, their possible role in immediate effects on covalent modification of other proteins,
and relatively slower effects on gene expression, physiology and behavior. 相似文献
105.
Kumari P Sharma P Srivastava S Srivastava MM 《Journal of industrial microbiology & biotechnology》2005,32(11-12):521-526
Metal species released into the environment by technological activities tend to persist indefinitely, circulating and eventually accumulating throughout the food chain, thus becoming a serious threat to the environment. Environment pollution by toxic metals occurs globally through military, industrial, and agricultural processes and waste disposal. Bioremediation processes are the target of recent research and are considered low-cost, ecofriendly methods to alleviate the current problems of water decontamination, particularly for remote and rural areas. The present piece of work reports the unexploited sorption properties of the powdered seed of the plant Moringa oleifera (SMOS) for the removal of Arsenic [As(III) and As(V)] from aqueous solutions. Sorption studies, using standard practices, result in the standardization of optimum conditions such as biomass dosages (2.0 g), metal concentrations (25 ppm), contact time (60 min) and volume of the test solutions (200 ml) at pH 7.5, for As(III) and pH 2.5 for As(V). Maximum sorption for As(III) and As(V) species is 60.21 and 85.6%, respectively. Protein/Amino acid-Arsenic interactions are found to play an important role in the biosorption process using plant biomass SMOS. 相似文献
106.
The membrane-bound hyaluronan synthase (HAS) from Streptococcus equisimilis (seHAS), which is the smallest Class I HAS, has four cysteine residues (positions 226, 262, 281, and 367) that are generally conserved within this family. Although Cys-null seHAS is still active, chemical modification of cysteine residues causes inhibition of wild-type enzyme. Here we studied the effects of N-ethylmaleimide (NEM) treatment on a panel of seHAS Cys-mutants to examine the structural and functional roles of the four cysteine residues in the activity of the enzyme. We found that Cys226, Cys262, and Cys281 are reactive with NEM, but Cys367 is not. Substrate protection studies of wild-type seHAS and a variety of Cys-mutants revealed that binding of UDP-GlcUA, UDP-GlcNAc, or UDP can protect Cys226 and Cys262 from NEM inhibition. Inhibition of the six double Cys-mutants of seHAS by sodium arsenite, which can cross-link vicinyl sulfhydryl groups, also supported the conclusion that Cys262 and Cys281 are close enough to be cross-linked. Similar results indicated that Cys281 and Cys367 are also very close in the active enzyme. We conclude that three of the four Cys residues in seHAS (Cys262, Cys281, and Cys367) are clustered very close together, that these Cys residues and Cys226 are located at the inner surface of the cell membrane, and that Cys226 and Cys262 are located in or near a UDP binding site. 相似文献
107.
Mishra S Kapoor N Mubarak Ali A Pardhasaradhi BV Kumari AL Khar A Misra K 《Free radical biology & medicine》2005,38(10):1353-1360
We have synthesized different bioconjugates of curcumin, which were tested for their pro- and antioxidant properties. In the present study five representative derivatives of curcumin, i.e., 4,4'-di-(O-acetyl) curcumin, 4,4'-di-(O-glycinoyl) curcumin, 4,4'-di-(O-glycinoyl-di-N-piperoyl) curcumin, 4,4'-di-(O-piperoyl) curcumin, and 4,4'-(O,O-cystinoyl)-3,3'-dimethoxydiphenyl-1,6-heptadiene-3,5-dione, were used for testing their apoptotic potential on tumor cells. Dipiperoyl and diglycinoyl derivatives showed higher apoptotic activity at lower concentrations, whereas diacetyl curcumin had slightly lower apoptotic activity on tumor cells. On the other hand, diglycinoyl-dipiperoyl and cystinoyl heptadiene derivatives had lost their apoptotic potential significantly. The apoptotic activity of these derivatives correlated very well with the generation of ROS by the tumor cells, whereas GSH levels remained unaltered. Our studies also indicate downregulation of Bcl-2 and participation of caspase-3 in the apoptotic death of tumor cells. 相似文献
108.
109.
ImmuPlus, a polyherbal commercial formulation was used to modulate the immune system of commercially important giant freshwater prawn M. rosenbergii. The prawns were fed with basal diet supplemented with ImmuPlus at 1g/kg feed for 4 weeks. Results showed that the phenoloxidase activity (PO), haemagglutination and lysozyme activities were significantly elevated in ImmuPlus-fed prawn up to 3 weeks of feeding and declined after 4 weeks of feeding. The total protein level in ImmuPlus-fed prawn raised up to 2nd week of feeding. Incorporation of ImmuPlus at the rate of 1g/kg feed in the diet of prawn for 3 weeks may be beneficial in raising the immune status of prawn. 相似文献
110.
Kohli E Gaspari M Raj HG Parmar VS Sharma SK van der Greef J Kumari R Gupta G Seema Khurana P Tyagi YK Watterson AC Olsen CE 《Biochimica et biophysica acta》2004,1698(1):55-66
The purification and characterization of the buffalo liver microsomal transacetylase (TAase) catalyzing the transfer of acetyl groups from a model acetoxy drug: 7,8-diacetoxy-4-methylcoumarin (DAMC) to GST3-3 has been described here. The enzyme was routinely assayed using DAMC and cytosolic GST as the substrates and was partially purified from microsomes of the buffalo liver. The enzyme was found to have approximate molecular of weight 65 kDa. The action of TAase and DAMC on liver cytosolic GST resulted in the formation of monoacetoxymonohydroxy-4-methylcoumarin (MAMHC) and 7,8-dihydroxy-4-methylcoumarin (DHMC), although the former was the major metabolite. The buffalo liver microsomal TAase exhibited hyperbolic kinetics and yielded K(m) (1667 microM) and V(max) (192 units) when the concentration of DAMC was varied keeping the concentration of GST constant. After having characterized the nature of the substrates and a product of the TAase-catalyzed reaction, we set out to identify the acetylated protein which is another product of the reaction. GST3-3 was used as a model protein substrate for the action of TAase using DAMC as the acetyl donor. The subunit of control and modified GST3-3 were separated by SDS-polyacrylamide gel electrophoresis (PAGE) and digested with trypsin. The tryptic peptides were extracted from the gel pieces and analyzed by matrix assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOFMS). The data search for calibrated and labeled mass peaks of peptides was performed on the Matrix Science Server using the search engine Mascot. The peptide maps so obtained covered 97% of the GST3-3 sequence. On comparison of MALDI peptide maps of modified and control GST, seven new peaks were recognized corresponding to the potentially acetylated peptides in peptide map. The mass value of each of them was 42 Da higher than the theoretical mass of a non-modified GST3-3 tryptic peptide, strongly suggesting acetylation. By examining the fragmentation patterns and by comparing experimental and predicted values for MS/MS daughter ions, the identity of the seven acetylated GST tryptic peptides could be confirmed by the application of LC/MS/MS. In the modified GST, N-terminal proline and six lysines (Lys(51), Lys(82), Lys(123), Lsy(181), Lys(191) and Lys(210)) were found to be acetylated. The structure of acetylated GST revealed that the lysines that underwent acetylation were peripheral in positions. 相似文献