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141.
The general accepted concept about the MRF as an unspecific ascending activating system concerns only one of its multiple functions. Investigations on more than 100 hooded rats of the Long-Evans strain with small bilateral symmetric lesions in dorsal, central and ventral subnuclei of the MRF brought out the following results pointing to further important functions: 1. Each lesion type produced a different syndrome of parameter changes of the spontaneous open field behavior with some common tendencies of reduced ambulatory and exploratory activities. 2. Visual placing responses were strongly reduced or totally abolished after lesions without tendencies of recovery. 3. Changes of locomotion and muscular tonus were quite different or even opposite in dorsal, central and ventral types of lesions. 4. In four tasks of postoperative active avoidance acquisition or retention and performance of preoperatively learned tasks the impairments were different related to the lesion type including a different loss in brightness discrimination. The results support the hypothesis that MRF subdivisions participate differently in information selection, tuning and coupling information with goal directed movements of different type. Lesions severely disturb the proper use of some information for a cue, especially visual cues when they are in the anterior part of the mesencephalon. 相似文献
142.
143.
The purpose of the presentation is to interconnect and illuminate certain parts of metabolism regarding stress signalling and defensive functions, including secondary metabolism in intact plants and plant tissue cultures. Increased cell/tissue levels of reactive oxygen species like H2O2, O2
- and ·OH and the metabolism of glutathione, are linked to defensive/secondary metabolism and tissue differentiation. Special attention is paid to nicotinamide. A hypothetical role of nicotinamide and its metabolites as stress signals is also put forward especially in connection with hypomethylation of DNA. A role of DNA hypomethylation, as a link between various types of stressors and the induction of plant devensive metabolism, is discussed. We suggest that nicotinamide or nicotinamide based substances may be of value within biotechnology for the production of valuable substances as well as for plant protection.Abbreviations BSO
buthionine sulfoximine
- CHS
chalcone synthase
- GSH
reduced glutathione
- GSSG
oxidized glutathione
- INA
isonicotinic acid
- NIC
nicotinamide
- PADPRP
poly(ADP-ribose)polymerase
- PAL
phenylalanine ammonia-lyase
- SA
salicylic acid
- SAM
S-adenosylmethionine
- SSB
single strand breakage 相似文献
144.
Eva Klingberg Mattias Lorentzon Jan G?thlin Dan Mellstr?m Mats Geijer Claes Ohlsson Elizabeth J Atkinson Sundeep Khosla Hans Carlsten Helena Forsblad-d’Elia 《Arthritis research & therapy》2013,15(6):R179
Introduction
Osteoporosis of the axial skeleton is a known complication of ankylosing spondylitis (AS), but bone loss affecting the peripheral skeleton is less studied. This study on volumetric bone mineral density (vBMD) and bone microarchitecture in AS was conducted to compare peripheral vBMD in AS patients with that in healthy controls, to study vBMD in axial compared with peripheral bone, and to explore the relation between vertebral fractures, spinal osteoproliferation, and peripheral bone microarchitecture and density.Methods
High-resolution peripheral quantitative computed tomography (HRpQCT) of ultradistal radius and tibia and QCT and dual-energy x-ray absorptiometry (DXA) of lumbar spine were performed in 69 male AS patients (NY criteria). Spinal radiographs were assessed for vertebral fractures and syndesmophyte formation (mSASSS). The HRpQCT measurements were compared with the measurements of healthy controls.Results
The AS patients had lower cortical vBMD in radius (P = 0.004) and lower trabecular vBMD in tibia (P = 0.033), than did the controls. Strong correlations were found between trabecular vBMD in lumbar spine, radius (rS = 0.762; P < 0.001), and tibia (rS = 0.712; P < 0.001).When compared with age-matched AS controls, patients with vertebral fractures had lower lumbar cortical vBMD (-22%; P = 0.019), lower cortical cross-sectional area in radius (-28.3%; P = 0.001) and tibia (-24.0%; P = 0.013), and thinner cortical bone in radius (-28.3%; P = 0.001) and tibia (-26.9%; P = 0.016).mSASSS correlated negatively with trabecular vBMD in lumbar spine (rS = -0.620; P < 0.001), radius (rS = -0.400; p = 0.001) and tibia (rS = -0.475; p < 0.001) and also with trabecular thickness in radius (rS = -0.528; P < 0.001) and tibia (rS = -0.488; P < 0.001).Adjusted for age, syndesmophytes were significantly associated with decreasing trabecular vBMD, but increasing cortical vBMD in lumbar spine, but not with increasing cortical thickness or density in peripheral bone. Estimated lumbar vBMD by DXA correlated with trabecular vBMD measured by QCT (rS = 0.636; P < 0.001).Conclusions
Lumbar osteoporosis, syndesmophytes, and vertebral fractures were associated with both lower vBMD and deteriorated microarchitecture in peripheral bone. The results indicate that trabecular bone loss is general, whereas osteoproliferation is local in AS. 相似文献145.
Microscale patchiness of plankton within a sharp pycnocline 总被引:1,自引:0,他引:1
Tiselius Peter; Nielsen Gitte; Nielsen Torkel Gissel 《Journal of plankton research》1994,16(5):543-554
Microscale distributions of plankton around the pycnocline werestudied over a 24 h period in the southern Kattegat, using agradient sampler which collects 20 samples over a 3 m depthinterval. Moderately elevated concentrations of phyto- and zooplanktonwere observed at the pycnocline. Microscale variance was highestfor adult copepods. Nauplii and copepodites were equally wellrepresented by sampling with ordinary vertical 5 1 water bottlesas with the horizontal 1.5 1 bottles of the gradient sampler.Adult copepods were underestimated by the vertical bottles.No vertical migration of dinoflagellates was observed over the3 m interval covered by the gradient sampler. Microscale correlationsbetween copepods and phytoplankton within the gradient samplerwere weak. Copepodites (mainly Oithona sp.) and the dinoflagellateProrocentrum micans showed the best correlation. 相似文献
146.
Siiri Hirmo Sørge Kelm Roland Schauer Bo Nilsson Torkel Wadström 《Glycoconjugate journal》1996,13(6):1005-1011
Helicobacter pylori is a human pathogen associated with gastritis and peptic ulcer. Adhesion properties ofH. pylori to various structures have been described in the literature, including evidence for sialic acid-binding. To study the specificity and frequency of sialic acid-binding, fourteenH. pylori strains were investigated using haemagglutination with derivatized erythrocytes carrying sialic acids only on defined glycans and using haemagglutination inhibition assays. From these studiesH. pylori strains can be grouped into sialic acid-dependent and sialic acid-independent classes. The sialic acid-dependent strains require -2,3-linked sialic acid for haemagglutination. The potential roles of sialic acid-dependent adhesions forH. pylori-related infections are discussed.Abbreviations Sia
sialic acids
- Neu5Ac
N-acetyl-neuraminic acid
- Neu5Gc
N-glycolylneuraminic acid
- Neu5Fm
N-formylneuraminic acid
- Neu5TFA
N-trifluoroacetylneuraminic acid
- RBC
human red blood cells (erythrocytes) 相似文献
147.
Pär Aleljung Hans-Olof Nilsson Xin Wang Patrik Nyberg Torsten Mörner Ibrahim Warsame Torkel Wadström 《FEMS immunology and medical microbiology》1996,13(4):303-309
Abstract Immunocompetent and immunodeficient BALB/cA mice were fed orally with 108 colony forming units of 2-day-old spiral or coccoid (12 days old) Helicobacter pylori strain NCTC 11637. Immunocompetent BALB/cA mice were also fed orally with decreasing numbers of spiral or coccoid forms of H. pylori . The gastrointestinal colonisation process was monitored for 34 days post-infection by heparin magnetic separation and subsequent enzyme immunoassay (EIA) for the detection of the H. pylori cells. Both mice types were colonised with H. pylori . The coccoid form of H. pylori gave higher EIA absorbance values and more efficient colonisation in the mice than the spiral form. Immunocompetent BALB/cA mice fed with the coccoid form of H. pylori exhibited an acute inflammation process in histopathological samples from the stomachs. In conclusion, H. pylori can infect both immunocompetent as well as immunodeficient BALB/cA mice and coccoids (viable but non-culturable) obtained after 12 days of culturing can infect BALB/cA mice. 相似文献
148.
Hamid-Reza Amini Felipe Ascencio Ariel Cruz-Villacorta Eduardo Ruiz-Bustos Torkel Wadström 《FEMS immunology and medical microbiology》1996,16(3-4):163-172
Abstract Western blot analysis (immunoblotting) of cell surface-associated proteins from Helicobacter pylori confirmed our previous findings that binding of human IgG is a common property (among H. pylori strains). Purification of the IgG-binding proteins (IGBP) was achieved by two purification steps, affinity chromatography on IgG-Sepharose and nickel chelate affinity chromatography. SDS-PAGE and immunoblotting analysis revealed a 60 kDa protein with affinity for peroxidase labeled human IgG. Solid phase binding assays showed that IgG binds to an immobilized protein (IGBP). The 60 kDa IGBP binds human IgG1 , IgG3 and IgM. Binding could be inhibited by the kappa chain of the human IgG, but not with its Fc fragment, nor with IgA or IgM. In addition, rabbit polyclonal antibodies raised against the 60 kDa IGBP blocked IgG binding. Monoclonal antibodies, specific to the Hsp60 heat shock protein of H. pylori recognized the 60 kDa IGBP as revealed by immunoblotting analysis, both in crude preparations and in the purified fractions. 相似文献
149.
Well-defined laboratory strains as well as 72 clinical strains ofStaphylococcus aureus isolated from bovine mastitis were investigated for surface hydrophobicity by the salt aggregation test (SAT).Staphylococcus aureus strain Cowan 1, rich in protein A and fibronectin-binding surface proteins, was found to show high surface hydrophobicity, whereas strain Wood 46, deficient in these surface proteins, showed low surface hydrophobicity. SAT showed a significant difference in surface hydrophobicity (P<0.001) between protein A-positive and A-negative strains measured by 2-test analysis. Comparison of SAT values with results obtained from hydrophobic interaction chromatography (HIC) showed a good correlation (P<0.025). A high-level protein-A-producing mutant (SA 113prA-3) showed increased surface hydrophobicity as compared with the parent strain (SA 113), whereas ten protein-A-negative mutants showed low surface hydrophobicity in SAT. Of the 72 clinical isolates tested by SAT, 47 (65%) showed autoaggregating properties, i.e., the strains aggregated even in isotonic buffers. Tween 80 (1% vol/vol) and ethylene glycol (50% vol/vol) prevented autoaggregation of some hydrophobic strains aggregating in phosphate-buffered saline. However, 2M of a chaotropic agent (NaSCN) was more efficient in preventing autoaggregation of the strains tested. Heating of cell suspensions to 80°C or 100°C as well as trypsin andStreptomyces griseus protease treatment generally caused a decrease in the cell surface hydrophobicity. This indicates that protein A, fibronectin-binding proteins, and probably other as yet unidentified proteins contribute to the high surface hydrophobicity of most strains isolated from bovine mastitis. 相似文献
150.
Amanda Jefferson Helen Leonard Aris Siafarikas Helen Woodhead Sue Fyfe Leanne M. Ward Craig Munns Kathleen Motil Daniel Tarquinio Jay R. Shapiro Torkel Brismar Bruria Ben-Zeev Anne-Marie Bisgaard Giangennaro Coppola Carolyn Ellaway Michael Freilinger Suzanne Geerts Peter Humphreys Mary Jones Jane Lane Gunilla Larsson Meir Lotan Alan Percy Mercedes Pineda Steven Skinner Birgit Syhler Sue Thompson Batia Weiss Ingegerd Witt Engerstr?m Jenny Downs 《PloS one》2016,11(2)