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J Bergman

Publications and source records attributed to J Bergman.

At least 55 records · Page 3Linked to original sources

High levels of dopamine activity in the basal ganglia of cigarette smokers.

OBJECTIVE: The authors' goal was to study presynaptic dopamine activity in smoking and nonsmoking human subjects in vivo. METHOD: [(18)F]Fluorodopa ([(18)F]DOPA) uptake K(i) values in the basal ganglia of nine smoking and 10 nonsmoking healthy men were measured with positron emission tomography. RESULTS: Significantly higher [(18)F]DOPA uptake was observed in both the putamen (average 17.3% higher) and the caudate (average 30.4% higher) of smokers than in those of nonsmokers. CONCLUSIONS: Smoking is related to greater dopamine activity in the human basal ganglia. Nicotine-induced dopamine activity may be a relevant mechanism in dependence on cigarette smoking.

Adult↗

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.

Aged↗

Transvaginal bladder neck suspension with Cooper's ligament fixation. Long-term urodynamic results.

OBJECTIVE: To evaluate the long-term urodynamic efficacy of transvaginal bladder neck suspension with Cooper's ligament fixation. STUDY DESIGN: Nineteen women underwent transvaginal bladder neck suspension with Cooper's ligament fixation. Patients underwent complete clinical and urodynamic testing before and four to five years after surgery. Cure was defined as absence of urine leakage with stress maneuvers at cystometric capacity and lack of symptoms of urine loss. RESULTS: A successful outcome was documented in 12/14 patients. One patient developed de novo detrusor instability, and two had stress incontinence. Five were lost to long-term follow-up. CONCLUSION: Transvaginal bladder neck suspension with Cooper's ligament fixation is an effective surgical option in the treatment of genuine stress incontinence.

Adult↗

Massive baclofen overdose.

A case is presented of a massive baclofen overdose with the highest blood baclofen concentrations currently reported. Interesting clinical features included profound hypotension, distributive shock and absent brainstem reflexes. Cerebral recovery was surprisingly slow but complete, and was then unexpectedly terminated by a sudden major splenic arterial haemorrhage followed by a severe haemorrhage of the aorta which proved to be due to cystic medial necrosis. This arterial anatomic abnormality and cause of death may have been coincidental, or may instead be a previously unreported complication of massive baclofen toxicity.

Journal Article↗

Protection against 12-O-tetradecanoylphorbol-13-acetate induced skin-hyperplasia and tumor promotion, in a two-stage carcinogenesis mouse model, by the 2,3-dimethyl-6(2-dimethylaminoethyl)-6H-indolo-[2,3-b]quinoxaline analogue of ellipticine.

The effects of topical applications of 2,3-dimethyl-6(2-dimethylaminoethyl)-6H-indolo-[2,3-b]quinoxaline (B-220), on 12-O-tetradecanoylphorbol-13-acetate (TPA) or benzoylperoxide (BPO) induced promotion of skin tumors and hyperplasia were studied in female SENCAR mice. Papillomas were induced by initiation with 7,12-dimethylbenz[a]anthracene (DMBA), followed by promotion biweekly with TPA or BPO. Administration of B-220 1 h before TPA promotion resulted in a prolonged latency period of tumor appearance and a significantly reduced (up to 15% of positive controls) papilloma yield at 20 weeks. Moreover, if B-220 treatment was terminated after 20 weeks and TPA treatment continued, papilloma development resumed indicating that initiated tumor cells were still present but were unable to grow with B-220 present. If B-220 pretreatment was not given during the first 10 weeks of TPA promotion, incidence at 20 weeks was not reduced but tumor multiplicity was still decreased. In addition a marked reduction of the TPA induced sustained epidermal hyperplasia was observed in the long term experiment. Neither the inflammatory response nor the increase in the number of apoptotic cells seen in short term experiment after a single TPA treatment were inhibited by B-220. B-220 administration before BPO promotion had no effect on the appearance of BPO induced papillomas or epidermal hyperplasia, suggesting that TPA and BPO promote tumor formation via at least partially different mechanisms. In experiments where B-220 was applied topically 1 h before DMBA initiation, little or no effect was seen. No morphological changes in mouse skin due to long term exposure (two times/week, 39 weeks) to B-220 were found. In conclusion, we present evidence that B-220 is a potent inhibitor of mouse skin tumor promotion by TPA, but has little effect on the initiation step or the survival of initiated cells.

9,10-Dimethyl-1,2-benzanthracene↗

Depressive symptoms and presynaptic dopamine function in neuroleptic-naive schizophrenia.

We have previously reported aberrations in the striatal presynaptic dopamine function in neuroleptic-naive schizophrenic patients compared to healthy controls (Hietala, J., Syvälahti, E., Vuorio, K. et al., 1995. Lancet 346, 1130-1131). In this extended study we explore whether the altered presynaptic dopamine function correlates with the clinical symptomatology in schizophrenia. Striatal dopamine synthesis capacity (6-[18F]fluorodopa (FDOPA) uptake, Ki values) was studied with positron emission tomography in 10 neuroleptic-naive schizophrenic patients and 13 healthy controls. The clinical symptomatology was characterized with the Positive and Negative Symptom Scale (PANSS). The patients had an increased FDOPA uptake in striatum and lacked the asymmetry in caudate FDOPA uptake (p = 0.0005), confirming our earlier results. Left striatal FDOPA uptake (Ki) values correlated negatively with depressive symptoms in a highly significant manner. On the other hand, paranoid symptomatology correlated positively with right putamen FDOPA uptake at a trend level (rho = 0.73, p < 0.02). The lack of asymmetry in caudate Ki values did not associate with any dimension of psychopathology. The major finding in this study is that depressive symptoms in neuroleptic-naive first-admission schizophrenia are associated with low presynaptic dopamine function. This link appears to be hemisphere-related and may have drug-treatment implications, e.g., in prediction of response to D2 receptor blocking antipsychotic drugs. A possible connection between paranoid symptomatology and subcortical hyperdopaminergia is suggested, but this remains to be further verified.

Adolescent↗

Striatal uptake of a novel PET ligand, [18F]beta-CFT, is reduced in early Parkinson's disease.

[18F] beta-CFT is a novel PET ligand for dopamine reuptake sites. In this study, [18F]beta-CFT uptake was studied in nine patients with early Parkinson's disease (PD) without antiparkinsonian medication and in six age-matched controls. The uptake of [18F]beta-CFT was calculated as a (region-cerebellum)/cerebellum ratio at 150-210 min after injection. The mean uptake in the putamen contralateral to the predominant symptoms (1.04+/-0.40, mean +/- SD; P<0.001) was reduced to 31% of the mean control value. In the "ipsilateral" putamen, the ratio in PD patients (1.50+/-0.50, P<0.001) was reduced to 45% of the control mean (3.33+/-0.61). Individually, all PD patients had [18F]beta-CFT uptake values below 2 SD from the control mean in the contralateral putamen. The decline in [18F]beta-CFT uptake in the caudate nucleus was milder than that seen in the putamen. The uptake was reduced contralaterally (2.19+/-0.47, P<0.01) to 67% and ipsilaterally (2.49+/-0.54, P<0.05) to 77% of the control mean (3.17+/-0.61). In the medial frontal cortex or dorsolateral prefrontal cortex, no significant difference in [18F]beta-CFT uptake between patients and controls was seen. In conclusion, [18F]beta-CFT is a powerful ligand to demonstrate presynaptic dopaminergic defect in PD and shows a clear separation of patient and control values.

Aged↗

Bladder neck suspension for stress urinary incontinence: how does it work?

The objective of this study was to compare urethral resistance as determined in pressure-flow studies before and after Burch retropubic urethropexy. Urethral resistance was retrospectively determined from pressure-flow studies in 178 patients before and 1 year after Burch retropubic urethropexy. Results of cotton swab tests, pressure transmission to the proximal urethra, and urethral functional length were also recorded. Results were analyzed statistically using the two-tailed paired t-test. Voiding studies in 176 patients were analyzed before and after Burch retropubic urethropexy. Mean urethral resistance increased significantly over preoperative values after successful surgery, from 0.051 to 0.099. The mean urethral resistance in patients in whom surgery failed to cure stress incontinence was unchanged from the preoperative value of 0.041. There was no direct correlation between stabilizing the bladder base, as evaluated by the cotton swab test, and cure of stress incontinence. When successful in curing genuine stress urinary incontinence, the Burch retropubic urethropexy increases urethral resistance. Creating bladder neck support without affecting urethral resistance does not, by itself, restore continence. Neurourol. Urodynam. 18:623-627, 1999.

Adult↗

The synthetic non-toxic drug 2,3-dimethyl-6(2-dimethylaminoethyl)-6H-indolo-(2,3-b)quinoxaline inhibits neutrophil production of reactive oxygen species.

The effects of the non-toxic drug 2,3-dimethyl-6(2-dimethylaminoethyl)-6H-indolo-(2,3-b)quinoxaline (B220) on the generation of reactive oxygen species froin human neutrophils were investigated. The data show that B220 inhibits neutrophil release of reactive oxygen species, as well as intracellular generation of reactive oxygen species. The inhibition is not achieved through direct oxygen radical scavenger activity of B220, and the drug has no immediate effects on the activity of the assembled oxidase. Radical production and release were inhibited by all agonists tested [i.e. the protein kinase C-activating phorbol ester phobol myristate acetate; the receptor-specific agonist N-formyl-methionyl-leucyl-phenylalanine (fMLP); and serum-opsonized yeast particles] in the presence of B220. The drug also inhibits phagocytosis and fMLP-induced mobilization of granules. However, based on the fact that the effects of B220 on phagocytosis and granule mobilization are much less significant than its effect on radical production, we suggest that the signal(s) affected by B220 is (are) located mainly downstream of the point at which the signals are generated to promote oxidase activation and phagocytosis or granule secretion, respectively.

Adult↗

Effects of the menstrual cycle on urodynamic work-up: should we change our practice?

The aim of this study was to compare urinary symptoms and urodynamic parameters during follicular and luteal phases of the menstrual cycle of women with lower urinary tract symptoms. Fifteen women were eligible and agreed to participate in the study. The subjects underwent urodynamic work-up, including filling urethrocystometry, urethral pressure profile and Valsalva leak-point pressure, cough stress test and subjective assessment of severity of symptoms in the mid-follicular and mid-luteal phases of the menstrual cycle. Mean age was 37 years (range 1843), mean parity 1 (range 0-3). Five women were found to have genuine stress urinary incontinence, 6 detrusor instability, 3 mixed incontinence and 1 urethral instability. Clinical diagnosis did not change and the urodynamic parameters were not statistically different in the two separate evaluations. A trend toward worsening of symptoms in the luteal phase in women with detrusor instability was identified. Our study suggests that the menstrual cycle does not significantly affect the work-up of women with lower urinary tract complaints.

Adolescent↗

Urodynamics changes in voiding after anti-incontinence surgery: an insight into the mechanism of cure.

OBJECTIVES: To measure the effect on voiding pressure and flow rate of three different operations for stress urinary incontinence. METHODS: In a previous study of cure rates, 289 women with genuine stress incontinence and genital prolapse were prospectively allocated in a randomized manner to one of three procedures: the Burch retropubic urethropexy, anterior repair, or the modified Pereyra procedure. In the current derivative study, we retrospectively evaluated the urodynamic indicators of voiding dysfunction in the original subjects preoperatively and at the 1-year postoperative follow-up visit. RESULTS: One hundred thirty-two charts were available for review. One year after surgery, pressure and flow during voiding were altered to more obstructive levels with the suspension procedures (Burch and modified Pereyra). The proportion of patients with obstructive and equivocal voiding patterns after the suspension procedures was significantly greater than after anterior repair. CONCLUSIONS: This post hoc comparison of randomized data shows a difference in postoperative voiding indexes between suspension procedures and anterior colporrhaphy. Successful bladder neck suspension depends on altering the pressure and flow during voiding to more obstructive levels. Suspension procedures alter the voiding pressure and flow toward obstruction to a greater extent than anterior repair.

Adult↗

Cerebral blood flow and glucose metabolism in long-term survivors of childhood acute lymphoblastic leukaemia.

Central nervous system treatment for childhood acute lymphoblastic leukaemia (ALL) has been reported to cause changes in cerebral blood flow and glucose metabolism. Little is known about the association of these functional changes with neuropsychological defects and structural changes. The aim of the present study was to assess the relationship between changes in regional cerebral blood flow and glucose utilisation in long-term survivors of ALL, and the association of these functional abnormalities with neurocognitive and structural defects. 8 survivors of childhood ALL were studied with single photon emission tomography (SPECT) using Tc99m-ethyl cysteinate dimer (ECD) as tracer and with positron emission tomography (PET) using 18F-fluorodeoxyglucose (FDG) as tracer. 8 healthy controls also underwent FDG-PET. All subjects also underwent magnetic resonance imaging and neuropsychological assessment 5 years after cessation of the therapy. Focal cerebral blood flow abnormalities were found in ECD-SPECT in 5 of the 8 survivors. Glucose utilisation appeared normal in the corresponding regions. However, glucose utilisation was decreased in thalamus and cerebellum in the survivors of ALL as compared with healthy controls. 3 patients had severe and 5 patients mild neurocognitive difficulties. The changes in cerebral blood flow and FDG uptake did not correspond neuroanatomically with the neurocognitive defects. Focal defects in cerebral blood flow in long-term survivors of ALL are not associated with changes in local cerebral glucose utilisation. Neurocognitive difficulties are not consistently associated with either changes in cerebral blood flow or with decreased glucose utilisation. Therefore, based on the present set of studies FDG-PET and ECD-SPECT cannot yet be recommended for the evaluation of long-term neurocognitive defects associated with treatment of ALL.

Adolescent↗

Uncoupling of fatty acid and glucose metabolism in malignant lymphoma: a PET study.

Increased use of glucose through glycolysis is characteristic for neoplastic growth while the significance of serum-free fatty acids for regulation of energy metabolism in cancer is poorly understood. We studied whether serum-free fatty acids (FFA) interfere with glycolytic metabolism of lymphoproliferative neoplasms as assessed with 2-F18-fluoro-2-deoxy-D-glucose ([F18]FDG) and positron emission tomography (PET). Twelve patients with newly diagnosed non-Hodgkin's lymphoma (n = 9) or Hodgkin's disease (n = 3) participated in this study before start of oncologic treatment. Each patient underwent two [F18]FDG PET studies within 1 week after overnight fast: once during high fasting serum FFA concentrations and once after reduction of serum FFA by administration of acipimox. Acipimox is a nicotinic acid derivative that inhibits lipolysis in peripheral tissues and induces a striking reduction in circulating FFA concentration. In all cases, dynamic PET imaging over the tumour area was performed for 60 min after injection of [F18]FDG. Both graphical analysis (rMR(FDG)) and single scan approach (SUV) were used to compare tumour uptake of [F18]FDG under high fasting FFA concentrations and after pharmacologically decreased FFA concentrations. Serum FFA concentrations were reduced significantly from 0.92+/-0.42 mmol I(-1)at baseline to 0.26+/-0.31 mmol I(-1) after acipimox administration (P = 0.0003). Plasma glucose, serum insulin and lactate concentrations were similar during both approaches. The retention of glucose analogue [F18]FDG in tumour was similar between baseline and acipimox studies. Median rMR(FDG) of a total of 12 involved lymph nodes in 12 patients was 21.9 micromol 100 g(-1) min(-1) (range 8.7-82.5) at baseline and 20.1 micromol 100 g(-1) min(-1)(range 10.7-81.7) after acipimox. The respective values for median SUV were 7.8 (range 3.6-18.6) and 6.0 (range 4.1-20.2). As expected, [F18]FDG uptake in myocardium was clearly enhanced by acipimox due to reduction of circulating FFAs. In conclusion, blood fatty acids appear to have minor significance for [F18]FDG uptake in lymphoma. This suggests that glucose utilization is uncoupled of FFA metabolism and indicates that glucose-free fatty acid cycle does not operate in lymphomatous tissue. Glucose appears to be the preferred substrate for energy metabolism in tumours, in spite of the high supply of FFAs in the fasting state. Although acipimox and other anti-lipolytic drugs have potential for treatment of catabolic state induced by cancer, they are not likely to interfere with tumour energy metabolism which is fuelled by glucose.

Adult↗

[18F]FDG-PET and whole-scalp MEG localization of epileptogenic cortex.

PURPOSE: To evaluate combined [18F]fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) and 122-channel whole-scalp magnetoencephalography (MEG) in lateralizing the epileptogenic cortex in patients whose routine presurgical evaluations gave discordant results about the location of the epileptic focus. METHODS: Nine patients (five women, four men) aged 13-40 years were studied. Subdural EEG (SEEG) was recorded from eight patients. Six patients were operated on. RESULTS: In seven of nine patients, PET and MEG agreed in localizing the epileptogenic cortex. When PET and MEG were in congruence, SEEG agreed with the findings. In five of six operated-on patients, PET and MEG results were congruent, and the outcome of the operation was successful. Two patients had discordant PET and MEG results. In one patient, PET showed bitemporal hypometabolism, whereas MEG showed epileptiform activity in the right parietal lobe. The surgical outcome of the palliative temporal lobectomy was poor. Another patient had unilateral temporal hypometabolism in PET and bitemporal activity in MEG. She was not operated on. CONCLUSIONS: In most patients, PET and MEG were congruent in locating the epileptogenic cortex. Thus the combination of these techniques may provide useful support for the localization of the seizure onset and reduce the need for invasive procedures.

Adolescent↗

Usefulness of a dopamine transporter PET ligand [(18)F]beta-CFT in assessing disability in Parkinson's disease.

OBJECTIVES: The usefulness of a novel dopamine transporter PET ligand, [(18)F]beta-CFT in assessing disability in Parkinson's disease was studied. METHODS: Twenty seven patients with Parkinson's disease in different disability stages (of which nine were patients with early disease) and nine healthy controls were studied. The regions of interest were drawn on a magnetic resonance image resliced according to the PET image. RESULTS: There was a significant reduction in [(18)F]beta-CFT uptake in the posterior putamen (to 18% of the control mean, p<0.00001), anterior putamen (28%, p<0.00001), and caudate nucleus (51%, p<0.00001) in the total population of patients with Parkinson's disease. The reduction in [(18)F]beta-CFT uptake was more pronounced with more severe disability of the patients, the correlations between the total motor score of the unified Parkinson's disease rating scale (UPDRS) and [(18)F]beta-CFT uptake being significant in the posterior putamen (r=-0.62 p=0.0005), anterior putamen (r=-0.64, p=0.0003), and the caudate nucleus (r=-0.62, p=0.0006). There was a significant negative correlation with putaminal [(18)F]beta-CFT uptake and the hypokinesia and rigidity scores, but not with the tremor score of the UPDRS motor part. In nine patients with early disease and without any antiparkinsonian medication the reduction in the [(18)F]beta-CFT uptake (average of ipsilateral and contralateral side) was reduced in the total putamen to 34% of the mean control value (p<0.00001). The corresponding figures in the other brain areas were: posterior putamen 21% (p<0.00001), anterior putamen 43% (p<0.00001), and caudate nucleus 76% (p<0.01). The reductions in [(18)F]beta-CFT uptake were more severe in the contralateral than in the ipsilateral side. Individually, [(18)F]beta-CFT uptake in the putamen in all patients was below 3 SD from the control mean. CONCLUSIONS: [(18)F]beta-CFT is a sensitive marker of nigrostriatal dopaminergic dysfunction in Parkinson's disease and can be used in the diagnosis, assessment of disease severity, and follow up of patients.

Aged↗

Myocardial blood flow, oxygen consumption, and fatty acid uptake in endurance athletes during insulin stimulation.

We have previously demonstrated reduced myocardial glucose uptake rates in hearts of endurance athletes, which could be due to increased use of alternative fuels or reduced energy demands. In the present study myocardial blood flow, oxygen consumption, and free fatty acid uptake were measured with [(15)O]H(2)O, [(15)O]O(2), [(18)F]FTHA, and positron emission tomography (PET) in 9 endurance athletes and 11 sedentary men during euglycemic hyperinsulinemia. Compared with sedentary men, athletes had 33% lower myocardial blood flow, 27% lower oxygen consumption, and 20% lower estimated myocardial work per gram of tissue. Myocardial fatty acid uptake rates were not significantly different in endurance athletes (0.83 +/- 0.29) and sedentary men (1.0 +/- 0.31 micromol. 100 g(-1). min(-1), P = 0.232). In conclusion, myocardial blood flow and oxygen consumption per unit mass of myocardium are reduced at rest in endurance athletes. This can be explained by reduced energy requirements per gram of tissue due to anatomic and physiological changes of the athlete's heart.

Adult↗

Anxious attachment and severity of depressive symptomatology in women.

The present research evaluated a conceptual model that links anxious attachment to depressive symptomatology in women. Four hundred and twenty women completed the following measures: Socio-demographic questionnaire, the Centre for Epidemiological Studies Depression Scale (CES-D), the Reciprocal Attachment Questionnaire, the Social Support Questionnaire, the Rosenberg Self-Esteem Scale and the Global Assessment of Recent Stress Scale. Results indicate that feared loss of the attachment figure, intense proximity seeking and lack of use of the attachment figure were predictive of depressive symptomatology. We also found that lower levels of self-esteem and higher levels of recent stress were predictive of depressive symptomatology. The implications of these findings for the understanding of symptoms of depression in women is discussed.

Adult↗

Impaired free fatty acid uptake in skeletal muscle but not in myocardium in patients with impaired glucose tolerance: studies with PET and 14(R,S)-[18F]fluoro-6-thia-heptadecanoic acid.

Free fatty acids (FFAs) are an important substrate for myocardial and skeletal muscle metabolism, and increased availability and oxidation of FFA are suggested to be associated with insulin resistance. This study was undertaken to assess whether myocardial or muscle uptake of FFA is altered in patients with impaired glucose tolerance (IGT). Eight healthy men (control group; age 48+/-1 years, BMI 25+/-1 kg/m2, mean +/- SE) and eight men with IGT (glucose-intolerant group; age 49+/-1 years, BMI 29+/-1 kg/m2) were studied in the fasting state. Myocardial oxygen consumption and blood flow and myocardial and femoral muscle FFA uptake rates were measured with positron emission tomography (PET) and [15O]O2, [15O]H2O, [15O]CO, and 14(R, S)-[18F]fluoro-6-thia-heptadecanoic acid ([18F]FTHA), a fatty acid tracer trapped into the cell after undergoing initial steps of beta-oxidation. Serum glucose and insulin concentrations were higher in the glucose-intolerant group during the PET study, but FFA concentrations were comparable between the groups. No differences between the groups were observed in the myocardial blood flow, oxygen consumption, fractional FTHA uptake rates, or FFA uptake indices (5.6+/-0.4 vs. 5.2+/-0.4 pmol x 100 g(-1) x min(-1), glucose-intolerant versus control, NS). In the femoral muscle, fractional FTHA uptake (0.0062+/-0.0003 vs. 0.0072+/-0.0003 min(-1), P = 0.044) and FFA uptake indices (0.30+/-0.02 vs. 0.43+/-0.04 min(-1), P = 0.020) were significantly lower in the glucose-intolerant group than in the control group. In conclusion, when studied at the fasting state and normal serum FFA concentrations, subjects with IGT have similar myocardial but lowered femoral muscle FFA uptake. This finding argues against the hypothesis that an increased oxidation of serum FFA, via the competition of glucose and FFA as fuel sources, is the primary cause for impaired peripheral glucose utilization and insulin resistance commonly observed in IGT.

Coronary Circulation↗