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91.
Capsicum are among the most extensively cultivated and consumed plant species in the world, because of their unique pungency, aroma and colour. The typical burning sensation caused by chili peppers is due to the occurrence of a group of alkaloids named capsaicinoids. In the present study, the production of solid callus and cell suspensions from hypocotyl explants of three different chili pepper cultivars (Capsicum annuum L. cv. Mazzolino, Capsicum chinense Jacq. cv. Naga Morich and Pimenta de Neyde), was optimised. In addition, C. chinense cv. Naga Morich cell suspensions were supplemented with biotic elicitors (methyl-jasmonate and chitosan) and with precursors and intermediates of capsaicin biosynthesis (vanillin, phenylalanine and valine), and both cells and media were analysed for capsaicinoid, polyphenol, flavonoid contents and for antioxidant activity. This is the first report regarding capsaicinoid elicitation with pure chitosan and with a combination of precursors of both phenylpropanoid and valine pathways. Overall, the highest capsaicinoid levels were detected in cell extracts from cultures treated with 10 μM methyl-jasmonate and with a combination of phenylalanine and valine amino acids (100 μM each). The present results confirm the possibility of using hypocotyl chili pepper cell suspensions to produce high amounts of health beneficial metabolites.  相似文献   
92.
Journal of Ethology - Facilitation is an ecological interaction in which the presence of one species (e.g., ecosystem engineers) alters the environment in a way that enhances growth, survival or...  相似文献   
93.

Objective

To assess decision-making in multiple sclerosis (MS) from third observer and patient perspectives.

Method

Audio recordings of first-ever consultations with a participating physician (88 outpatients, 10 physicians) at four tertiary MS care clinics in Italy, were rated by a third observer using the Observing Patient Involvement in Shared Decision Making (OPTION) and by patients using the Perceived Involvement in Care Scale (PICS).

Results

Mean patient age was 37.5, 66% were women, 72% had MS, and 28% had possible MS or other disease. Mean PICS subscale scores (range 0 poor, 100 best possible) were 71.9 (SD 24.3) for "physician facilitation" (PICS-F); 74.6 (SD 22.9) for "patient information exchange" (PICS-I); and only 22.5 (SD 16.2) for "patient decision making" (PICS-DM). Mean OPTION total score (0 poor, 100 best possible) was 29.6 (SD 10.3). Poorest OPTION scores were found for items assessing “preferred patient approach to receiving information” and “preferred patient level of involvement.” Highest scores were for “clinician drawing attention to identified problem”, “indicating need for decision making,” and “need to review the decision.” Consultation time, woman physician, patient-physician gender concordance and PICS-F were associated with higher OPTION total score; older physician and second opinion consultation were associated with lower OPTION score.

Conclusions

In line with findings in other settings, our third observer findings indicated limited patient involvement abilities of MS physicians during first consultations. Patient perceptions of physician skills were better than third observers’, although they correlated. Consultations with women physicians, and younger physicians, were associated with higher third observer and patient-based scores. Our findings reveal a need to empower Italian MS physicians with better communication and shared decision-making skills, and show in particular that attention to MS patient preferences for reception of information and involvement in health decisions, need to be improved.  相似文献   
94.
We previously reported that pre- and postsynaptic 5-hydroxytryptamine (5-HT) receptors effectively control glutamatergic transmission in adult rat cerebellum. To investigate where 5-HT acts in the glutamate ionotropic receptors/nitric oxide/guanosine 3',5'-cyclic monophosphate (cGMP) pathway, in the present study 5-HT modulation of the cGMP response to the nitric oxide donor S-nitroso-penicillamine (SNAP) was studied in adult rat cerebellar slices. While cGMP elevation produced by high-micromolar SNAP was insensitive to 5-HT, 1 microM SNAP, expected to release nitric oxide in the low-nanomolar concentration range, elicited cGMP production and endogenous glutamate release both of which could be prevented by activating presynaptic 5-HT1D receptors. Released nitric oxide appeared responsible for cGMP production and glutamate release evoked by 1 microM SNAP, as both the effects were mimicked by the structurally unrelated nitric oxide donor 2-(N,N-diethylamino)-diazenolate-2-oxide (0.1 microM). Dependency of the 1 microM SNAP-evoked release of glutamate on external Ca2+, sensitivity to presynaptic release-regulating receptors and dependency on ionotropic glutamate receptor functioning, suggest that nitric oxide stimulates exocytotic-like, activity-dependent glutamate release. Activation of ionotropic glutamate receptors/nitric oxide synthase/guanylyl cyclase pathway by endogenously released glutamate was involved in the cGMP response to 1 microM SNAP, as blockade of NMDA/non-NMDA receptors, nitric oxide synthase or guanylyl cyclase, abolished the cGMP response. To conclude, in adult rat cerebellar slices low-nanomolar exogenous nitric oxide could facilitate glutamate exocytotic-like release possibly from parallel fibers that subsequently activated the glutamate ionotropic receptors/nitric oxide/cGMP pathway. Presynaptic 5-HT1D receptors could regulate the nitric oxide-evoked release of glutamate and subsequent cGMP production.  相似文献   
95.
New silver(I) complexes have been synthesised from the reaction of AgNO3, monodentate PR3 (PR3 = P(o-tolyl)3, P(m-tolyl)3, P(p-tolyl)3, P(p-C6H4F), SeP(C6H5)3) or bidentate tertiary (dppe = bis(diphenylphosphane)ethane, dppf = 1,1′-bis(diphenylphosphane)ferrocene) phosphanes and potassium dihydrobis(3-nitro-1,2,4-triazolyl)borate, K[H2B(tzNO2)2]. These compounds have been characterized by elemental analyses, FT-IR, ESI-MS and multinuclear (1H and 31P) NMR spectral data. The adduct {[H2B(tzNO2)2]Ag[P(m-tolyl)3]2} has been characterized by single crystal X-ray studies. In the former, the H2B(tzNO2)2 acts as a monodentate ligand utilizing the coordinating capability of only one of the additional (exo-) ring nitrogens to complete the coordination array about the silver atom.  相似文献   
96.
Presynaptic regulation of acetylcholine release in the CNS   总被引:1,自引:0,他引:1  
The release of ACh appears to be under the control of autoreceptors localized on cholinergic nerve terminals. Moreover, the process can be regulated by transmitters other than ACh or by modulators either through receptor-mediated or carrier-mediated mechanisms. In this chapter we report on our recent results concerning the regulation of the release of ACh by ACh itself, 5-HT and GABA in the rat hippocampus. In particular it will be shown: 1) that the release of the cholinergic transmitter can be inhibited through muscarinic receptors of the M3 subtype; 2) that 5-HT can interact with ACh by depressing ACh release through the activation of receptors of the 5-HT1B subtype; 3) that the release of ACh can be enhanced by GABA by a novel mechanism involving a selective penetration of the amino acid into the cholinergic terminals.  相似文献   
97.
New copper(I) complexes have been synthesised from the reaction of CuCl with 4-(diphenylphosphane)benzoic acid and lithium tris(1H-pyrazol-1-yl)methanesulfonate, Li(SO(3))C(pz)(3), sodium hydrotris(3-trifluoromethyl-1H-pyrazol-1-yl)borate, NaHB[3-(CF(3))pz](3), potassium dihydrobis(1H-1,2,4-triazol-1-yl)borate, KH(2)B(tz)(2), hydrotris(1H-1,2,4-triazol-1-yl)borate, KHB(tz)(3), sodium hydrotris(1H-pyrazol-1-yl)borate, NaHB(pz)(3), potassium hydrotris(3,5-dimethyl-1H-pyrazol-1-yl)borate KHB(3,5-Me(2)Pz)(3) or potassium hydrotris(4-bromo-1H-pyrazol-1-yl)borate KHB(4-Brpz)(3). The complexes obtained have been characterized by elemental analyses and FT-IR in the solid state, and by NMR (1H and 31P[(1)H]) spectroscopy and conductivity measurements in solution. The solution data are consistent with partial dissociation of the sterically hindered complexes by way of breaking of Cu-P and Cu-N bonds. Electrospray mass spectrometry has been used to investigate the relative properties of the 4-(diphenylphosphane)benzoic acid and of the "scorpionate" ligands towards copper(I) ions. Chemiluminescence technique was used to evaluate the superoxide scavenging activity of these new copper complexes.  相似文献   
98.
Bacteriophages have been known to be present in the gut for many years, but studies of relationships between these viruses and their hosts in the intestine are still in their infancy. We isolated three bacteriophages specific for an enteroaggregative O104:H4 Escherichia coli (EAEC) strain responsible for diarrhoeal diseases in humans. We studied the replication of these bacteriophages in vitro and in vivo in a mouse model of gut colonization. Each bacteriophage was able to replicate in vitro in both aerobic and anaerobic conditions. Each bacteriophage individually reduced biofilms formed on plastic pegs and a cocktail of the three bacteriophages was found to be more efficient. The cocktail was also able to infect bacterial aggregates formed on the surface of epithelial cells. In the mouse intestine, bacteriophages replicated for at least 3 weeks, provided the host was present, with no change in host levels in the faeces. This model of stable and continuous viral replication provides opportunities for studying the long-term coevolution of virulent bacteriophages with their hosts within a mammalian polymicrobial ecosystem.  相似文献   
99.
The cardiac type 2 ryanodine receptor (RYR2) is activated by Ca2+-induced Ca2+ release (CICR). The inherent positive feedback of CICR is well controlled in cells, but the nature of this control is debated. Here, we explore how the Ca2+ flux (lumen-to-cytosol) carried by an open RYR2 channel influences its own cytosolic Ca2+ regulatory sites as well as those on a neighboring channel. Both flux-dependent activation and inhibition of single channels were detected when there were super-physiological Ca2+ fluxes (>3 pA). Single-channel results indicate a pore inhibition site distance of 1.2 ± 0.16 nm and that the activation site on an open channel is shielded/protected from its own flux. Our results indicate that the Ca2+ flux mediated by an open RYR2 channel in cells (∼0.5 pA) is too small to substantially regulate (activate or inhibit) the channel carrying it, even though it is sufficient to activate a neighboring RYR2 channel.  相似文献   
100.
Vegetative mycelial cells of Armillaria are expected to have diploid nuclei. Cells from a single mycelium therefore would not be expected to differ from one another for ecologically relevant quantitative traits. We isolated two sets of basidiome cell lines (from spores and stipe cells) and one set of vegetative cell lines (from an attached rhizomorph) from a single contiguous Armillaria gallica mycelium. We isolated a second set of vegetative cell lines from the soil 20 cm from the above basidiome-rhizomorph complex. In all four sets of cell lines in situ DAPI-DNA measurements showed cells are haploid and quantitative-trait analyses of cell lines grown at different water potentials revealed high levels of among-cell-line genetic variation for both growth and phenotypic plasticity. Haploidy and the existence of ecologically relevant genetic variation within vegetative individuals are unexpected and mean that a process similar to evolutionary adaptation could take place within the soma of a genetic individual. We believe this is a key to understanding how large A. gallica mycelia survive exposure to variation in ecological conditions during lives that potentially span several tree (host) generations.  相似文献   
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