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E Nurmi

Publications and source records attributed to E Nurmi.

At least 19 recordsLinked to original sources
PubMed2001

Personality traits and brain dopaminergic function in Parkinson's disease.

A distinctive personality type, characterized by introversion, inflexibility, and low novelty seeking, has been suggested to be associated with Parkinson's disease. To test the hypothesis that Parkinson's disease is associated with a specific dopamine-related personality type, the personality structures of 61 unmedicated Parkinson's disease patients and 45 healthy controls were examined. Additionally, in 47 Parkinson's disease patients, the dopaminergic function in the brain was directly measured with 6-[(18)F]fluoro-l-dopa ((18)F-dopa) positron emission tomography (PET) with MRI coregistration. The novelty-seeking personality score, supposedly associated with the parkinsonian personality, was slightly lower in the Parkinson's disease group compared with controls, but it did not have a significant relationship with (18)F-dopa uptake in any of the brain regions studied (r = -0.12 to 0.11, P > 0.15). The harm-avoidance personality score, associated with anxiety and depression, was clearly increased in patients with Parkinson's disease and it had a paradoxical, highly significant positive correlation with the (18)F-dopa uptake in the right caudate nucleus (r = 0.53, P = 0.04, Bonferroni corrected for 220 comparisons). Although the results of this study are not in disagreement with the concept of low-novelty-seeking personality type in Parkinson's disease, the personality type does not seem to be dopamine dependent. The correlation between the personality trait of harm avoidance and (18)F-dopa may reflect a specific feedback circuitry of neurotransmitters that is associated with negative emotionality in Parkinson's disease.

Aged↗
PubMed2001

[(18)F]FDOPA and [(18)F]CFT are both sensitive PET markers to detect presynaptic dopaminergic hypofunction in early Parkinson's disease.

The aim of this study was to compare two PET ligands, 6-[(18)F]fluoro-L-dopa ([(18)F]FDOPA) and (18)F-labeled CFT, 2beta-carbomethoxy-3beta-(4-[(18)F]-fluorophenyl)tropane ([(18)F]CFT), in detecting presynaptic dopaminergic hypofunction in early Parkinson's disease (PD). These ligands reflect different aspects of presynaptic dopaminergic function, since [(18)F]FDOPA mainly reflects 6-[(18)F]fluorodopamine (fluorodopamine) synthesis and storage whereas [(18)F]CFT uptake is related to dopamine transporter function. Eight de novo patients with PD who had never been on antiparkinsonian medication were investigated with [(18)F]FDOPA and [(18)F]CFT PET. Five healthy volunteers were studied as controls. In PD patients, both [(18)F]FDOPA and [(18)F]CFT uptakes were significantly reduced both in the contralateral and ipsilateral anterior and posterior putamen. The reduction was greatest in the contralateral posterior putamen (to 28% of control mean for [(18)F]FDOPA, P < 0.0001 and to 16% for [(18)F]CFT, P < 0.0001). Individually, all patients' [(18)F]FDOPA and [(18)F]CFT uptake values in the contralateral anterior and posterior putamen were below 3 SD of the control mean. In the caudate nucleus, the mean uptake of both tracers was significantly reduced both ipsilaterally and contralaterally, but less severely than in the putamen (to 69% of the control mean for [(18)F]FDOPA, P = 0.003 and to 60% for [(18)F]CFT, P = 0.001 contralaterally). Our results show that both [(18)F]FDOPA as well as [(18)F]CFT sensitively detect presynaptic dopaminergic hypofunction in early PD. They demonstrate a considerable reduction of tracer uptake that is greatest in the posterior putamen, followed by the anterior putamen and the caudate nucleus.

Aged↗
PubMed2001

Rate of progression in Parkinson's disease: a 6-[18F]fluoro-L-dopa PET study.

The aim of this study was to investigate the rate of progression in Parkinson's disease (PD) with 6-[(18)F]fluoro-L-dopa (FDOPA) positron emission tomography (PET). We investigated 21 patients with PD and eight healthy controls. Ten of the patients were de novo at the time of the first PET scan and antiparkinsonian medication was started thereafter, with a favourable response. A FDOPA PET scan was carried out twice at an approximately 5-year interval. The regions of interest were drawn on individual magnetic resonance imaging (MRI) images, matched with the PET images. At the first PET scan, in PD patients the mean k(i)(occ) (x 10(-3) min(-1)) in the anterior putamen was 5.6 +/- 2.7 (mean +/- S.D.; 55% of the control mean) and in the posterior putamen 4.5 +/- 2.4 (45% of the control mean). The k(i)(occ) value for the caudate nucleus was 7.5 +/- 2.1 (x 10(-3) min(-1); 76% of the control mean). The FDOPA uptake declined by the time of the second PET scan and the annual rate of decline was 8.3 +/- 6.3% (P < 0.001) of the baseline mean in the anterior putamen and 10.3 +/- 4.8% (P < 0.001) in the posterior putamen. In the caudate nucleus, FDOPA uptake decreased by 5.9 +/- 5.1% (P < 0.001) of the baseline mean per year. The estimated preclinical period was longest for the posterior putamen being 6.5 years. For the anterior putamen the preclinical period was 4.6 years. In the caudate nucleus, the estimated FDOPA uptake was at normal level at disease onset. In healthy controls, there was no significant decline in FDOPA uptake in any striatal subregion. Our results suggest that the disease process in PD first affects posterior putamen, followed by the anterior putamen and the caudate nucleus, but once started, the absolute rate of decline is the same. In healthy controls, no significant decline in FDOPA was detected.

Adult↗
PubMed2001

Increased frontal [(18)F]fluorodopa uptake in early Parkinson's disease: sex differences in the prefrontal cortex.

Previous imaging studies in Parkinson's disease have focused mainly on the striatum, a region with very high dopaminergic activity. Using modern high-sensitivity 3D [(18)F]fluorodopa (Fdopa)-PET, mesocortical monoamine projections can be studied. To study the frontal monoaminergic system in unmedicated early Parkinson's disease in vivo, we examined 20 early Parkinson's disease patients (10 women, 10 men) and 16 healthy subjects (nine women, seven men) with 3D Fdopa-PET, using standard region-of-interest-based analysis with MRI co-registration. Women with Parkinson's disease had 87% higher Fdopa uptake in the right dorsolateral prefrontal cortex (area 46) compared with men with Parkinson's disease, whereas there was no sex difference in the control group (sex x disease interaction, P = 0.03). The uptake in the right dorsolateral prefrontal cortex was 82% higher in men with Parkinson's disease and 219% higher in women with Parkinson's disease compared with control groups (effect of disease, P < 0.0001). Also in the left dorsolateral prefrontal cortex and in the medial frontal cortex, early Parkinson's disease patients had significantly (18-94%) higher Fdopa uptake compared with healthy controls. In the putamen, both men and women with Parkinson's disease had a significantly lower (27-46%) uptake compared with healthy controls. These results indicate that frontal monoaminergic activity is increased and that there is a sex difference in the prefrontal monoaminergic system in early Parkinson's disease. The reported sex difference may be linked to clinical sex differences in the symptoms and treatment response in Parkinson's disease.

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PubMed2000

Cognitive impairment and the brain dopaminergic system in Parkinson disease: [18F]fluorodopa positron emission tomographic study.

OBJECTIVE: To investigate the role of the brain dopaminergic system in cognitive impairment in patients with Parkinson disease (PD). DESIGN: We studied 28 patients with PD and 16 age-matched healthy control subjects using [18F] fluorodopa (fluorodopa F 18) positron emission tomography. Patients with PD showed a variable degree of cognitive impairment, which was assessed using the Mini-Mental State Examination and detailed neuropsychologic assessment, including tests sensitive for frontal lobe function. RESULTS: [18F] Fluorodopa uptake was reduced in the putamen (to 36% of the control mean; P<.001), the caudate nucleus (to 61% of the control mean; P<.001), and the frontal cortex (to 45% of the control mean; P<.001) in patients with PD compared with controls. There was no significant association between the degree of overall cognitive impairment of patients and [18F] fluorodopa uptake values. The influx constant (Ki(occ)) in the caudate nucleus had a negative association with performance in the attention-demanding Stroop interference task, especially with the interference time. The Ki(occ) in the frontal cortex had a positive correlation with performance in the digit span (backwards), verbal fluency, and verbal immediate recall tests. Thus, the better the patient performed in tasks demanding immediate and working memory and executive strategies, the better the [18F] fluorodopa uptake in the frontal cortex. In the putamen, no significant correlation was seen between the Ki(occ) value and any of the cognitive tests. The severity of the motor symptoms of PD and [18F]fluorodopa uptake showed a negative correlation in the putamen (r = -0.38; P = .04), and in the caudate nucleus a similar trend was seen (r = -0.36; P = .06). CONCLUSIONS: Reduced [18F]fluorodopa uptake in PD in the caudate nucleus (and frontal cortex) is related to impairment in neuropsychologic tests measuring verbal fluency, working memory, and attentional functioning reflecting frontal lobe function. This indicates that dysfunction of the dopamine system has an impact on the cognitive impairment of patients with PD. However, our results do not exclude the possibility of more generalized cognitive impairment in PD, the pathophysiology of which is probably different and more generalized.

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PubMed2000

Reproducibility and effect of levodopa on dopamine transporter function measurements: a [18F]CFT PET study.

The objective of this article was to study the reproducibility and effect of levodopa on dopamine transporter function measurements using 2beta-carbomethoxy-3beta-(4-[18F]fluorophenyl)tropane ([18F]CFT) positron emission tomography (PET). Seven de novo patients with Parkinson's disease (PD) were studied twice, before and after three months of levodopa medication. Eight healthy volunteer subjects participated in the reproducibility study. The [18F]CFT PET scan was done twice with an interval of approximately 2.5 months. The regions of interest (anterior and posterior putamen, caudate nucleus, and cerebellum) were drawn on individual magnetic resonance imaging (MRI) images, matched with the PET images, and copied onto the PET images. The [18F]CFT uptake was calculated as the region-cerebellum:cerebellum ratio at 180 to 210 minutes. Three-month levodopa treatment in PD patients had no significant effect on [18F]CFT uptake in any striatal subregion between the two PET scans. In PD patients, the percent change from baseline was 4.1% in the anterior putamen, 1.9% in the posterior putamen, and 4.0% in the caudate nucleus. No significant differences in [18F]CFT uptake between the first and second PET scan in any striatal subregion occurred in healthy controls. The intraclass correlation, indicating the reproducibility of the PET scan within subjects, was 0.94 for the anterior putamen, 0.86 for the posterior putamen, and 0.91 for the caudate nucleus. The percent change from baseline was 4.0% in the anterior putamen, 1.1% in the posterior putamen, and 2.8% in the caudate nucleus. Long-term levodopa treatment in PD patients had no effect on the [18F]CFT uptake in the striatum and the test-retest reproducibility was very high. These findings confirm [18F]CFT as a suitable ligand to monitor progression of PD.

Adult↗
PubMed2000

Progression in Parkinson's disease: a positron emission tomography study with a dopamine transporter ligand [18F]CFT.

We studied the rate of progression of striatal dopamine transporter function in Parkinson's disease (PD). Eight patients with early PD without antiparkinsonian medication and 7 healthy volunteers were investigated with [18F]CFT positron emission tomography (PET). The PET scan was carried out twice at an approximate 2-year interval. The uptake of [18F]CFT was calculated as a region-cerebellum:cerebellum ratio at 180 to 210 minutes after injection. At the first PET scan, the [18F]CFT uptake in PD patients in the putamen was 1.45 +/- 0.45 (mean +/- SD) (42% of the control mean) and 2.43 +/- 0.59 in the caudate nucleus (76% of the control mean). The ratios declined by the time of the second PET scan, and the rate of annual decline of the baseline mean in PD patients was 13.1% in the putamen and 12.5% in the caudate nucleus. In controls, the corresponding figures were 2.1% for the putamen and 2.9% for the caudate nucleus. The decline in [18F]CFT uptake was significantly higher in PD patients than in controls. Thus, dopamine transporter ligands such as [18F]CFT seem to be sensitive markers for the rate of progression in PD.

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PubMed1998

Effects of growth-promoting antimicrobials on inhibition of Yersinia enterocolitica O:3 by porcine ileal microflora.

The survival of Yersinia enterocolitica serotype O:3 was examined in an in vitro model of the porcine ileum in the presence of normal ileal microflora using a medium supplemented with the growth-promoting antimicrobials avoparcin, spiramycin, tylosin, carbadox and olaquindox, or without any antimicrobials, at 39 degrees C for 5 d. Growth of Y. enterocolitica was inhibited in all trials in the following order: avoparcin < carbadox < spiramycin < no feed additives < tylosin < olaquindox. The media supplemented with avoparcin, carbadox and spiramycin supported the survival of Y. enterocolitica up to 5 d. When incubated with the normal ileal microflora without any growth-promoting antimicrobials, Y. enterocolitica could not be isolated after 4 d. With olaquindox and tylosin, Y. enterocolitica was not detected after 3 d.

Animals↗
PubMed1996

Note: inhibition of the growth of Yersinia enterocolitica O:3 by the microflora of porcine caecum and ileum in an in vitro model.

The growth of Yersinia enterocolitica O:3 was tested in an in vitro model of the porcine intestine at the physiological temperature of 39 degrees C of growing pigs. The model supported a stable population of Y. enterocolitica at a level 10(8)-10(9) cells ml-1. Plasmid profile analysis and the Ca(2+)-dependent proportion of the population suggested that the great majority of the Y. enterocolitica population retained the 70 kb virulence plasmid, pYV, throughout the experimental period of 5 d. The growth of Y. enterocolitica was substantially inhibited by the ileal and the caecal flora compared to the growth of the bacterium alone. Yersinia enterocolitica was not isolated after 3 d of cultivation.

Animals↗
PubMed1994

Selective solid-phase extraction of urinary 2,3-dinor-6-ketoprostaglandin F1 alpha for determination with radioimmunoassay.

This paper describes a method for selective two-step solid-phase extraction of urinary 2,3-dinor-6-ketoprostaglandin F1 alpha for reliable determination with radioimmunoassay. In the immunoreactivity profile of non-selectively extracted urine after HPLC separation, over 90% of the total 2,3-dinor-6-ketoprostaglandin F1 alpha immunoreactivity consisted of interfering material coeluting with 6-ketoprostaglandin F1 alpha and 2,3-dinor-6-ketoprostaglandin F1 alpha. Among the alkyl silica sorbents studied (methyl, butyl, octyl, and octadecyl), an efficient separation of 2,3-dinor-6-ketoprostaglandin F1 alpha from 6-ketoprostaglandin F1 alpha and the lowest immunoreactive concentration of analyte were achieved in extraction on the methyl silica sorbent by elution of 2,3-dinor-6-ketoprostaglandin F1 alpha with chloroform: hexane (85:15, v/v) from the cartridge. The proportion of specific immunoreactivity could be further increased by two-step extraction of sample on methyl silica cartridges, first at pH 3 and then at pH 10 using diethyl ether:hexane (85:15, v/v) and chloroform as eluent, respectively. After this, a high correlation was found with concentrations of samples determined by radioimmunoassay using three different antisera. A significant correlation of values was also observed between samples measured by radioimmunoassay and those measured by GC-MS. The values of 12-h excretion of 2,3-dinor-6-ketoprostaglandin F1 alpha in eight volunteers (268 +/- 204 ng/g creatinine, mean +/- SD) as well as the inhibitory effect of acetylsalicylic acid (74 +/- 12%) are in accordance with those reported in the literature. This selective extraction procedure provides a high validity in radioimmunoassay without requiring subsequent TLC or HPLC purification.

6-Ketoprostaglandin F1 alpha↗
PubMed1994

Association af changes in the bacterial ecology of bovine mastitis with changes in the use of milking machines and antibacterial drugs.

The results of mastitis bacteriology made by the National Veterinary and Food Research Institute in Finland during the past 50 years (1.15 million samples) are viewed in relation to simultaneous changes in dairy cow management. Although intensive preventive measures have been applied for decades, the prevalence of bovine mastitis has not decreased. Instead, pathogenic bacteria are becoming progressively less susceptible to the available therapy. In part this must be due to the emergence of antibiotic resistant strains of bacteria, but it seems that the bacterial spectrum has also changed. The incidence of Streptococcus agalactiae (group B streptococci) has decreased, while in contrast, the incidence of staphylococci, initially Staphylococcus aureus and later coagulase-negative staphylococci, has increased. Results suggest that external pressure, like changes in animal husbandry, including antimicrobial treatments and introduction of modern milking machines, act as selective forces on the bacterial species which cause bovine mastitis.

Animals↗
PubMed1992

Use of competitive exclusion to protect newly-hatched chicks against intestinal colonisation and invasion by Salmonella enteritidis PT4.

1. The recommended dose of a commercial competitive exclusion (CE) product (BROILACT) was given orally to newly-hatched broiler chicks to protect them against oral challenge by Salmonella enteritidis PT4. 2. In 5 replicate trials, half of the birds thus treated and half from untreated control groups were examined for salmonellas at 5 d and the other half at 12 d after challenge. 3. Caecal contents were examined quantitatively while heart, liver and spleen samples were examined qualitatively by enrichment. 4. The treatment effectively prevented both colonisation of the caeca and invasion of the other organs by S. enteritidis PT4; the average number of salmonellas was less than 10 colony forming units (cfu)/g of caecal contents in the treated birds and more than 10 million cfu/g in the untreated birds. 5. Infection of organs other than the caeca was completely prevented by protective treatment, whereas 38% of the untreated birds were still infected at the end of the trial.

Animal Husbandry↗
PubMed1991

The growth of salmonellae in tomatoes.

The growth of Salmonella enteritidis, S. infantis and S. typhimurium in tomatoes was studied at 7,22 and 30 degrees C. The pH values of tomatoes varied from 3.99 to 4.37 before incubation and from 3.90 to 4.36 after incubation at different temperatures. No growth was observed at 7 degrees C. S. enteritidis, S. infantis and S. typhimurium grew from cell densities of 1.2 x 10(1), 0.7 x 10(1) per g to 2.0 x 10(6), 2.3 x 10(6) and 7.1 x 10(6) per g, respectively, at 22 degrees C in 24 h. At 30 degrees C, the number of bacteria was about one logarithmic unit higher than at 22 degrees C after the same incubation time. The results of this study demonstrated a possible risk of tomatoes as vehicles of Salmonella spp.

Food Microbiology↗
PubMed1991

Pilot-scale testing of the competitive exclusion method in chickens.

1. The efficacy of a commercial competitive exclusion (CE) product, BROILACT, was tested in pilot-scale trials involving groups of 100 broiler chicks. 2. Each group was challenged with Salmonella infantis through contact with infected seeder birds and numbers of salmonellae in the caecal contents were determined weekly. 3. The performance of the birds was also monitored over a 5-week period. 4. The results showed a gradual decline of the infection, even in the untreated groups, and a dose-dependent response to treatment. 5. The treatment had no significant effect on the performance of the birds.

Animals↗
PubMed1990

Fate of Listeria monocytogenes in orally dosed chicks.

The fate of Listeria monocytogenes in chicks perorally dosed with these bacteria at 2 days of age was determined by bacterial enumeration, immunoperoxidase staining and histological examination of the liver, muscle and gastrointestinal tract. Results revealed listerial egress from the digestive tract and elimination of the organism from the body in most of the chicks within 9 days post-inoculation. L. monocytogenes was isolated from the caecum of only one of 10 chicks examined at 4 weeks post-inoculation. Results indicate that chickens are not likely to be common reservoirs of L. monocytogenes. Intestinal carriage of L. monocytogenes by poultry may frequently be transient, resulting from ingestion of Listeria-contaminated feed and soil.

Animals↗
PubMed1988

The inhibition of the growth of Bacillus cereus in liver sausage.

The growth of Bacillus cereus is a problem in liver sausage especially when the sausages are stored at high temperatures. Even concentrations of greater than 10(6)/g have been detected. In this study we found that when combining glucono-delta-lactone, sodium erythorbate and citric acid with sodium nitrite and salt the growth of B. cereus could be delayed or totally inhibited.

Animals↗