| 31. |
- Nilsson, Charlotta, et al.
(author)
-
Characterisation of a pre-cell hit detector to be used in single cell irradiation experiments at the Lund Nuclear Microprobe
- 2008
-
In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - Amsterdam : Elsevier BV. - 0168-583X .- 1872-9584. ; 266:21, s. 4808-4815
-
Journal article (peer-reviewed)abstract
- This paper describes the characterisation of an ultra-thin silicon semicondoctor Delta E detector to be used as a pre-cell ion hit detector in single ion experiments on individual, living cells. The characteristics of interest for this specific application are the hit detection efficiency, which has to be close to 100% to enable bombardment with either a single ion or a counted number of ions, the beam spreading, which should be as small as possible to maintain the targeting accuracy, and the vacuum tightness, since the detector is intended, if possible, to be used simultaneously as vacuum window. The hit detection efficiency was shown to be above 99% when detecting alpha particles or 2 MeV protons, the increase in beam size was about 1 mu m and the vacuum tightness was comparable to that of the Si3N4 wafer which is normally used as vacuum window, thus the Delta E detector fulfils the main criteria to function properly as a single ion hit detector. (C) 2008 Elsevier B.V. All rights reserved.
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| 32. |
- Nilsson, Christer, et al.
(author)
-
Distribution of peptidergic nerves in the choroid plexus, focusing on coexistence of neuropeptide Y, vasoactive intestinal polypeptide and peptide histidine isoleucine
- 1990
-
In: Regulatory Peptides. - : Elsevier BV. - 1873-1686 .- 0167-0115. ; 27:1, s. 11-26
-
Journal article (peer-reviewed)abstract
- Choroid plexus from rat, guinea-pig, rabbit and pig was investigated by light-microscopic immunohistochemistry and by radioimmunoassay for the presence of neuropeptides. A moderately dense supply of nerve fibers containing neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP), respectively, was found around blood vessels and in close relation to the secretory epithelium in both pig and rabbit, while lower densities of nerve fibers were found in rat and guinea-pig. Peptide concentrations ranged from 10-40 pmolequivalents/g (pmoleqv/g) for NPY and 0.5-6 pmoleqv/g for VIP in all four species. Peptide histidine isoleucine (PHI) immunoreactive nerve fibers were present in pig choroid plexus at a lower density than NPY and VIP but with a similar distribution. Low concentrations of substance P (0.3-3 pmoleqv/g) and calcitonin gene-related peptide (0.1-3 pmoleqv/g) were found to a varying degree in choroid plexus tissue from the different species, while immunohistochemical investigation was unable to detect any immunoreactive nerve fibers. NPY was often found to coexist with VIP and PHI in pig choroid plexus, while a lesser amount of nerve fibers showed coexistence of NPY and the noradrenaline synthetizing enzyme, dopamine-beta-hydroxylase. Surgical sympathetic denervation by excision of the superior cervical ganglion in the rabbit abolished NPY-containing nerve fibers, as revealed by immunohistochemistry, but only decreased NPY levels by one third, which may be due to different identity of the peptide being detected by the two techniques. It is concluded that NPY-containing nerve fibers have a dual origin in the choroid plexus and coexist with either noradrenaline or VIP/PHI.
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| 33. |
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| 34. |
- Nilsson, Christer, et al.
(author)
-
Epithelial cells purified from choroid plexus have receptors for vasoactive intestinal polypeptide
- 1991
-
In: Brain Research. - 1872-6240. ; 542:2, s. 241-247
-
Journal article (peer-reviewed)abstract
- Using the choroid plexus from pig a method has been developed to purify the epithelial cells from the underlying vascularized connective tissue stroma. An epithelial cell fraction was obtained that showed a purity of at least 95%, as determined by light microscopic analysis. The epithelial cells were investigated for the presence of binding sites for the neurotransmitter peptide, vasoactive intestinal polypeptide (VIP). Suspensions of epithelial cells were found to have high affinity binding sites for 125I-labelled VIP, with maximum binding obtained after 30 min incubation at 20 degrees C with a concentration of 50 micrograms cell protein per sample. Competition experiments with displacement of [125I]VIP binding by increasing concentrations of unlabeled VIP indicated the presence of a single class of binding sites with a Kd of 3 nM and a binding capacity of 970 pmol/g cell protein. Cross-linking of [125I]VIP to epithelial cells with disuccinimido dithiobis (propionate) (DSP), followed by SDS-polyacrylamide gel electrophoresis, demonstrated binding to a single 55 kD protein. The receptor was highly specific for VIP as binding was only inhibited in the presence of high concentrations of the related peptides helodermin, growth hormone-releasing factor, secretin, and peptide histidine isoleucine. This is the first demonstration of VIP-binding to choroid plexus epithelial cells.
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| 35. |
- Nilsson, Charlotta, et al.
(author)
-
Evaluation of a pre-cell hit detector for the future single ion hit facility in Lund
- 2006
-
In: Nuclear Instruments & Methods in Physics Research. Section B: Beam Interactions with Materials and Atoms. - : Elsevier BV. - 0168-583X .- 1872-9584. ; 249:1-2, s. 924-927
-
Journal article (peer-reviewed)abstract
- Currently, a single ion hit facility, for irradiation of single cells with single, light MeV ions is under development at the Lund Nuclear Microprobe. In this paper, a novel approach to the ion detection issue is presented. A silicon detector, a type utilized at other facilities for post-cell ion detection, has been investigated as a possible option for pre-cell hit detection. If proven successful, this detector could possibly also be used simultaneously as vacuum window. The first experiments carried out on the 9 mu m thick silicon detector, with an area of 4 mm(2), have been aimed at investigations of signal-to-noise ratio and efficiency. The results thus far reveal a low noise level and a noise distribution, which is well separated from the signal peak. However, the efficiency remains a problem, since at present it is far from the required 100%.
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| 36. |
- Nilsson, Christer, et al.
(author)
-
Neuroendocrine regulatory mechanisms in the choroid plexus-cerebrospinal fluid system
- 1992
-
In: Brain research. Brain research reviews. ; 17:2, s. 109-138
-
Research review (peer-reviewed)abstract
- The CSF is often regarded as merely a mechanical support for the brain, as well as an unspecific sink for waste products from the CNS. New methodology in receptor autoradiography, immunohistochemistry and molecular biology has revealed the presence of many different neuroendocrine substances or their corresponding receptors in the main CSF-forming structure, the choroid plexus. Both older research on the sympathetic nerves and recent studies of peptide neurotransmitters in the choroid plexus support a neurogenic regulation of choroid plexus CSF production and other transport functions. Among the endocrine substances present in blood and CSF, 5-HT, ANP, vasopressin and the IGFs have high receptor concentrations in the choroid plexus and have been shown to influence choroid plexus function. Finally, the choroid plexus produces the growth factor IGF-II and a number of transport proteins, most importantly transthyretin, that might regulate hormone transport from blood to brain. These studies suggest that the choroid plexus-CSF system could constitute an important pathway for neuroendocrine signalling in the brain, although clearcut evidence for such a role is still largely lacking.
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| 37. |
- Nilsson, Christer, et al.
(author)
-
The neuropeptides vasoactive intestinal polypeptide, peptide histidine isoleucine and neuropeptide Y modulate [3H]noradrenaline release from sympathetic nerves in the choroid plexus
- 1990
-
In: European Journal of Pharmacology. - 1879-0712. ; 181:3, s. 247-252
-
Journal article (peer-reviewed)abstract
- The neurotransmitter peptides vasoactive intestinal polypeptide (VIP), peptide histidine isoleucine (PHI) and neuropeptide Y (NPY) are located in nerve fibers supplying the pig choroid plexus, which receives an abundant sympathetic innervation. We characterized the release of [3H]noradrenaline ([3H]NA) from this tissue elicited by electrical field stimulation and studied the effects of the above-mentioned peptides on this release. The release of [3H]NA was found to be almost exclusively of neurogenic origin, despite there being a marked non-neuronal uptake of [3H]NA into the epithelium of the choroid plexus. NPY significantly decreased the release of [3H]NA by approximately 10% while VIP and PHI enhanced release by up to 25 and 35%, respectively, indicating a possible synergistic role of the two latter peptides and NA in the choroid plexus.
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| 38. |
- Nilsson, Christer, et al.
(author)
-
Transitorisk global amnesi - godartat tillstånd som även kan drabba unga
- 2005
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In: Läkartidningen. - 0023-7205. ; 102:24, s. 7-1905
-
Journal article (peer-reviewed)abstract
- Transient global amnesia (TGA) occurs mostly in middle-aged and elderly individuals, and is generally believed to be very rare in individuals less than 40 years of age. We present three cases of TGA in young persons (16-22 years). They all had a medical history and presented symptoms fulfilling the criteria for TGA. Physical examinations and investigations were all normal. All three presented their symptoms while playing football. Reviewing the literature the suggested causes are partly different for TGA in old and young people, respectively. The present report confirms that TGA may also occur in younger individuals. We propose that single TGA is a benign condition also in younger persons and that the investigation should be similar to that of TGA in older age groups.
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| 39. |
- Nilsson, Jan-Henrik, et al.
(author)
-
Dining in the Skies. A historical account of hospitality in aviation
- 2019
-
In: Fika, Hygge and Hospitality : The cultural complexity of service organisation in the Öresund Region - The cultural complexity of service organisation in the Öresund Region. - 2001-9874. - 9789170613029 ; 39, s. 107-129
-
Book chapter (peer-reviewed)
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| 40. |
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