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71.
72.
Agneta Nordberg Anders Lilja Hans Lundqvist Per Hartvig Kaarina Amberla Matti Viitanen Ulrika Warpman Monika Johansson Ewa Hellstrm-Lindahl Peter Bjurling Karl-Johan Fasth Bengt Lngstrm Bengt Winblad 《Neurobiology of aging》1992,13(6):747-758
Three patients with Alzheimer's disease, a 68-year-old woman with mild dementia and 2 men (aged 64 and 72 years) with moderate dementia were treated orally with the cholinesterase inhibitor tacrine (tetrahydroaminoacridine), 80 mg daily, for several months. The patients were investigated using positron emission tomography (PET) prior to, and after 3 weeks and 3 months of treatment. The PET studies involved a multi-tracer system consisting of [18F]-fluoro-deoxy-glucose (18F-FDG) (tracer for glucose metabolism); 11C-butanol (cerebral blood flow) and (S)(−)- and (R)(+)-[N-11C-methyl]-nicotine (nicotinic receptors; cholinergic neural activity). Tacrine treatment increased the uptake of 11C-nicotine to the brain. Significant reduced difference in uptake between the two enantiomers (S)(−)- and (R)(+)11C-nicotine was observed in the frontal and temporal cortices after tacrine treatment in all three patients. The kinetic analysis indicated increased binding of (S)(−)11C-nicotine in brain compatible with a restoration of nicotinic cholinergic receptors. The most pronounced effect was observed after 3 weeks and 3 months treatment in the patient with mild dementia. An increase in cerebral glucose utilization was found in the 68-year-old patient with mild dementia but also slightly in the 64-year-old man with moderate dementia when treated with tacrine for 3 months. Tacrine administration did not affect cerebral blood flow. The PET data obtained after 3 weeks of tacrine treatment was paralleled by improvement in neuropsychological performance. This study shows in vivo by PET neurochemical effects induced in brain by treatment with tacrine to Alzheimer patients. Intervention with tacrine in the early course of the disease might be necessary for clinical improvement. 相似文献
73.
Hassan AB Nikitina-Zake L Padyukov L Karlsson G Gupta M Lundberg IE Sanjeevi CB 《Human immunology》2003,64(2):290-296
In order to investigate major histocompatibility complex (MHC) class I chain-related gene A (MICA), tumor necrosis factor (TNFa), -308TNFA, and human leukocyte antigen (HLA-DR/DQ) polymorphisms in mixed connective tissue disease (MCTD), we analyzed 24 patients and 229 healthy controls from Sweden. MICA and TNFa typing was performed by polymerase chain reaction (PCR) and genotyping. HLA-DR and -DQ were genotyped using PCR-sequence specific primers (PCR-SSP) and PCR-sequence-specific oligonucleotide probe (PCR-SSOP), respectively. For analysis of -308TNFA polymorphisms we performed PCR with restriction endonuclease enzymes. We found that the MICA5.1-5.1 genotype was positively associated with MCTD. Shared epitope genes (DRB1*01 and DRB1*04) were also significantly positively associated with MCTD. Polymorphism of -308TNFA was not differently distributed in MCTD patients compared with controls. Furthermore, we demonstrated that frequencies of three estimated haplotypes were increased in MCTD patients compared with controls. Interestingly, the haplotype with MICA allele 4 together with DRB1*04 and TNF1 alleles gives the most specific pattern for MCTD patients compared with controls. Our study demonstrates a clear contribution of HLA loci in susceptibility to MCTD in the Swedish population. Susceptibility to MCTD may be linked to the MICA4/HLA-DRB1*04/TNF1 haplotype and MICA 5.1-5.1 genotype. Mixed connective tissue disease was also associated with shared epitope genes, which in RA has been associated with a more severe disease. Whether these genotypes affect the clinical phenotype of MCTD needs to be determined. 相似文献
74.
Evaluation of Etest MBL for detection of blaIMP-1 and blaVIM-2 allele-positive clinical isolates of Pseudomonas spp. and Acinetobacter spp 总被引:10,自引:0,他引:10
Lee K Yong D Yum JH Lim YS Bolmström A Qwärnström A Karlsson A Chong Y 《Journal of clinical microbiology》2005,43(2):942-944
The Etest MBL (AB BIODISK, Solna, Sweden) correctly differentiated all 57 isolates of Acinetobacter spp. and Pseudomonas aeruginosa with the bla(IMP-1) allele and 135 of 137 (98.5%) Acinetobacter spp. and Pseudomonas spp. isolates with the bla(VIM-2) allele. The Etest MBL was reliable for detecting the IMP-1- and VIM-2-producing Pseudomonas and Acinetobacter isolates. 相似文献
75.
The occurrence of antibodies to human C-reactive protein (CRP) was analysed by enzyme-linked immunosorbent assay (ELISA) in 56 patient sera known to contain antibodies to double-stranded DNA (dsDNA) and in 16 sera from patients with primary Sj?gren's syndrome (SS), 15 rheumatoid arthritis, 31 Crohn's disease, and 37 ulcerative colitis. Eighty-seven per cent of the patients with anti-dsDNA antibodies had systemic lupus erythematosus (SLE) and the remaining had autoimmune hepatitis. The cut-off for positive anti-CRP test was set at the 95th percentile of 100 healthy blood donors. Twenty of 56 anti-dsDNA sera (36%) and two of 16 SS sera (13%) had antibodies reactive with human CRP, whereas all other samples were negative. Thirteen of 27 SLE patients (48%) were positive on at least one occasion. The sera containing anti-CRP antibodies only reacted with surface-bound antigen, but not with native CRP in solution. In conclusion, we found that autoantibodies to CRP are common in sera from patients with anti-dsDNA antibodies. It is not likely that this explains the relative failure of CRP response in patients with active SLE. However, it cannot be excluded that anti-CRP autoantibodies have other biological potentials of pathophysiological interest in SLE, for instance by binding to CRP deposited on cell and tissue surfaces. 相似文献
76.
Vonen Barthold Bertheussen Kjell Giæver Anton K. Florholmen Jon Burhol Per G. 《Methods in Cell Science》1992,14(2):45-50
Summary Serum contains insulin degrading components. We have evaluated the insulin and somatostatin secretion from isolated rat pancreatic islets during a 2-wk culture period using three different serum-containing media, and one serum-free medium with a synthetic serum replacement. Islets incubated in serum-free medium elicited significantly higher daily insulin and somatostatin secretions than islets incubated in the serum-containing media. After a 2-wk culture period, islets from the serum-free medium secreted significantly more insulin and somatostatin than islets cultured in other media when stimulated with 25 mmol/liter glucose together with 15 mmol/liter theophylline. We conclude that the serum-free medium is superior for long-term culture of rat pancreatic islets. 相似文献
77.
In a study of immunotherapy 41 children with seasonal rhinoconjunctivitis due to deciduous tree pollen allergy were monitored by means of symptom scoring, patient self-evaluation, conjunctival provocation tests and lymphocyte proliferation in vitro to the allergen. The lymphocyte responsiveness to birch pollen decreased significantly during the first year of immunotherapy. However, neither the lymphocyte responsiveness before treatment nor changes in lymphocyte reactivity during the immunotherapy correlated with the clinical efficacy of the therapy as evaluated by changes in symptom scores, self-evaluation or conjunctival provocation test changes in the individual patients. The results indicate the lymphocyte responsiveness to an allergen cannot be used to select patients for immunotherapy, i.e. to predict whether a patient would benefit from immunotherapy or not, or to evaluate the effects of immunotherapy after beginning the treatment. However, lymphocyte proliferation response to an allergen indicates clinical sensitivity. 相似文献
78.
The authors found tardive dyskinesia (TD) in 23.5% of 200 hospitalized schizophrenic patients, most of whom had received neuroleptic treatment for at least two years. The frequency and severity of TD increased with age, and the more advanced the age at which the patient started taking neuroleptics, the more likely it was that TD would develop. Severe TD was more common in men than in women. Prolonged treatment with neuroleptics or the use of antiparkinsonism drugs increased the risk of TD. 相似文献
79.
80.
Sister chromatid exchange (SCE) was studied in cultured lymphocytes from a limited series of 21 like-sexed twin pairs; 11 monozygotic (MZ) and 10 dizygotic (DZ) pairs. The 18 subjects, who were between 57 and 61 years old, had an SCE mean value () of 8.0 whereas the 24 subjects between 33 and 39 years of age had a mean of 6.8. The difference was statistically significant ( P <0.001). The effect of age appeared to be present in both sexes. No significant difference was found between females (%7.3) and males (%7.5), nor between smokers (%7.3) and non-smokers (%7.4). Drug users had a slightly higher mean (%7.9) than non-users (= 7.0) ( P < 0.05). This trend was found in each age group. The within-pair variance was slightly higher in DZ than in MZ pairs. The difference was not significant. We conclude that genetic factors are probably not a major source of subject variation in SCE mean value. 相似文献