PubMed Health⌕ Search

Biomedical subjects

M Laine

Publications and source records attributed to M Laine.

At least 19 recordsLinked to original sources
PubMed2006

Duration of the haemodynamic action of a 24-h infusion of levosimendan in patients with congestive heart failure.

AIMS: To determine the duration of haemodynamic and neurohormonal action of a 24-h infusion of levosimendan in heart failure. METHODS AND RESULTS: This was a double-blind, parallel group study in patients with New York Heart Association class II to IV heart failure. Twenty-two patients, with left ventricular ejection fraction <35% and pulmonary capillary wedge pressure (PCWP) above 12 mmHg, were randomised to receive either levosimendan (12 microg/kg followed by a continuous infusion of 0.1-0.2 microg/min) or placebo. Invasively measured cardiac output (CO) increased from 4.3 l/min to 5.4 l/min in the levosimendan group at 6 h. PCWP decreased from 20 mmHg to 15 mmHg in response to levosimendan. Echocardiographically measured maximal effect on PCWP occurred after 6 h, whereas CO reached its highest value at 24 h. The estimated duration of the decrease in PCWP was 7-9 days, and in CO was 12-13 days. Plasma NT-proANP and NT-proBNP levels reached their lowest values at days 3 and 2, and the treatment effect was estimated to last 16 and 12 days, respectively. The long-acting haemodynamic responses reflect levels of the active metabolites OR-1896 and OR-1855, maximal metabolite levels occurred at day 3. CONCLUSIONS: Levosimendan infusion achieved a rapid improvement in haemodynamic parameters in patients with congestive heart failure with maximal effects occurring 1-3 days after starting the infusion, effects were sustained for up to at least a week.

Atrial Natriuretic Factor↗
PubMed2005

CERAD test performances in amnestic mild cognitive impairment and Alzheimer's disease.

OBJECTIVES: The aim of the study was to examine the Consortium to Establish a Registry for Alzheimer's Disease (CERAD) test performances cross-sectionally in patients suffering from amnestic mild cognitive impairment (MCI) and mild Alzheimer's disease (AD). Moreover, we wanted to determine the sensitivity to amnestic MCI and mild AD, as well as the specificity of different CERAD subtests in our study groups. MATERIAL AND METHODS: Fifteen healthy elderly individuals, 15 amnestic MCI patients and 15 probable AD patients suffering from mild dementia were tested with the CERAD neurocognitive dementia screening test. RESULTS: Significant differences were found in all CERAD tests except Constructional praxis (copy) and Clock drawing between the controls and the AD group. The MCI group was differentiated from the controls only in the Wordlist learning test. In the language tests the sensitivity to MCI and AD was quite low and the specificity very high. In the savings scores the sensitivity to AD was high, but the specificity rather low. The Wordlist recognition test screened no false positives using the current cut-off score and the sensitivity to AD was 0.6, but only one MCI patient was detected using the current cut-off score. Raising the cut-off score also raised the sensitivity to MCI without dramatic loss of specificity. Cut-off scores for the Wordlist learning test and Wordlist delayed recall, which have been found to differentiate normal aging from dementia, are lacking in the Finnish CERAD. The current data indicates that the Wordlist learning test might be relatively sensitive to MCI. CONCLUSIONS: The results indicate that the Finnish CERAD test battery with its current cut-off scores has low sensitivity to MCI, and using it as a sole cognitive screening instrument for MCI and preclinical dementia might result in false negatives.

Aged↗
PubMed2005

Role of TNF-alpha and its receptors in pericoronitis.

The classic stimulus for cellular cytokine production is bacterial lipopolysaccharide (endotoxin). It was therefore hypothesized that tumor necrosis factor-alpha (TNF-alpha) may be responsible for pericoronitis. TNF-alpha and its receptors were detected by immunohistochemical staining in third molar pericoronitis in ten patients and ten healthy control samples. The percentage of TNF-alpha positive cells was high in pericoronitis (p = 0.0317). TNF receptors TNF-R1 and TNF-R2 were found in macrophage- and fibroblast-like cells, vascular endothelial cells in post-capillary venules, and basal epithelial cells in pericoronitis, but were only weakly expressed in controls. Increased expression of interleukin-1beta and vascular cell adhesion molecule-1 was found as a biological indicator of TNF-alpha ligand-receptor interaction. Explanted tissues acquired destructive potential upon TNF-alpha stimulation, whereas TNF-alpha blockers controlled it in inflamed tissues. These findings suggest that, in pericoronitis, inflammatory and resident cells produce and respond to potent pro-inflammatory cytokine TNF-alpha, with pathogenic and potential therapeutic relevance.

Adult↗
PubMed2004

Sustained cardiomyocyte apoptosis and left ventricular remodelling after myocardial infarction in experimental diabetes.

AIMS/HYPOTHESIS: Diabetes is known to reduce survival after myocardial infarction. Our aim was to examine whether diabetes is associated with enhanced cardiomyocyte apoptosis and thus interferes with the post-infarction remodelling process in myocardium in rat. METHODS: Four weeks after intravenous streptozotocin (diabetic groups) or citrate buffer (controls) injection, myocardial infarction was produced by ligation of left descending coronary artery. Level of cardiomyocyte apoptosis was quantified by TUNEL and caspase-3 methods. Collagen volume fraction and connective tissue growth factor were determined under microscope. Left ventricular dimensions were evaluated by echocardiography and planimetry. RESULTS: The number of apoptotic cardiomyocytes was equally high in diabetic and non-diabetic rats after 1 week from infarction. At 12 weeks after infarction the number of apoptotic cells was higher in the diabetic as compared to non-diabetic rats both in the border zone of infarction and in non-infarcted area. Correspondingly, left ventricular end diastolic diameter, relative cardiac weight, connective tissue growth factor-expression and fibrosis were increased in diabetic compared with non-diabetic rats with myocardial infarction. CONCLUSION/INTERPRETATION: Sustained cardiomyocyte apoptosis, left ventricular enlargement, increased cardiac fibrosis and enhanced profibrogenic connective tissue growth factor expression were detected after myocardial infarction in experimental diabetes. Apoptotic myocyte loss could be an important mechanism contributing to progressive dilatation of the heart and poor prognosis after myocardial infarction in diabetes.

Animals↗
PubMed2004

Sindbis viruses and other alphaviruses as cause of human arthritic disease.

Amongst the arthritis-causing arboviruses, i.e. those spread by insects, the alphavirus group is of special interest. These viruses occasionally cause vast outbreaks, such as O'nyong-nyong in Africa in 1959. In Fennoscandia, Sindbis-related Ockelbo, Pogosta, or Karelian fever viruses have been found to cause significant morbidity. The major symptoms in addition to joint inflammation are fever, fatigue, headache and rash. The joint symptoms may persist for weeks, even months. The diagnosis is based on the clinical picture and serology. The causative viruses are closely related but not identical. It appears that at least in Finland the Pogosta disease is more common than thought, and the symptoms may often be overlooked. Several factors related to the viruses, their hosts, and global environmental changes may affect the spread of these viruses. All over the world arbovirus-caused diseases have increased, because of global changes.

Alphavirus Infections↗
PubMed2004

Estrogen receptor-beta is the predominant estrogen receptor subtype in human oral epithelium and salivary glands.

Many studies have shown that the oral mucosa and salivary glands are sensitive to estrogen action. However, the expression of estrogen receptors (ERs) within these tissues is an area of controversy. ERs exist as two subtypes (ERalpha and ERbeta), and we hypothesized that the incongruity between ER expression and estrogen sensitivity may result from differential expression of ER subtypes in oral tissues. To test this hypothesis, we analyzed oral mucosal and salivary gland samples for ERalpha and ERbeta protein expression by immunohistochemistry from a cross-section of patients attending hospital for surgical problems of the head and neck. ERalpha was not detected in oral buccal and gingival epithelium or in salivary glands. In contrast, ERbeta was widely expressed at high levels in all oral tissues studied. Within these tissues, ERbeta was observed primarily in keratinocytes and salivary gland acinar and ductal cells. Our results demonstrating the expression of only the ERbeta subtype within oral tissues may explain the contradictory results from previous studies investigating ER expression in these tissues. Importantly, these results suggest that estrogens may act via ERbeta in oral tissues and explain the effect of hormonal changes on the oral mucosa as well as on saliva secretion and composition.

Adult↗
PubMed2004

Hippocampal MRI volumetry in cognitively discordant monozygotic twin pairs.

OBJECTIVE: To investigate whether hippocampal atrophy, a proxy for incipient Alzheimer's disease, can be detected in non-demented monozygotic co-twins of demented twins by using volumetric magnetic resonance imaging (MRI). METHODS: Seven pairs of monozygotic female twins discordant for cognitive function (mean (SD) age 75 (4) years), and 10 age and education matched healthy controls (seven women, three men; mean age 73 (3) years) were studied with volumetric MRI. RESULTS: The mean normalised right hippocampal volume was 31% lower (p = 0.002) in the demented twins, and 6% lower (p = 0.45) in the non-demented twins than in the controls. In the left hippocampus, the mean normalised volume was 36% lower (p<0.001) in the demented twins, and 9% lower (p = 0.13) in the non-demented twins than in the controls. CONCLUSIONS: Significant hippocampal atrophy was detected in the demented twins compared with the controls. This is in line with previous imaging and pathological studies, with hippocampus showing the early changes in Alzheimer's disease. In the non-demented twins, only a minor, non-significant reduction was observed in the hippocampal volumes compared with the controls. This could reflect gene-environment interactions that have protected the non-demented twins longer than their demented co-twins and contributed to the relative preservation of their hippocampal volumes, or it could be a sign of preclinical Alzheimer's disease in the non-demented twins.

Aged↗
PubMed2003

Semantic decision making in early probable AD: a PET activation study.

We studied the neural correlates of semantic decision making in early probable Alzheimer disease patients and age-matched controls by measuring changes in relative cerebral blood flow by PET (oxygen-15) while they performed a category-specific word-matching task with either animal or artefact names. In comparison to a baseline (matching words by physical identity), semantic decision making elicited increased blood flow in the left frontal lobe (BA 6, 11, 47) and in the contralateral cerebellum in the controls. The only category-specific difference in controls was activation of the left supplementary motor area (BA 6) when making decisions on artefacts. In contrast, the patients recruited more extensive brain regions, encompassing areas in the left frontal lobe (BA 44, 45, 47), right occipital cortex (BA 18), midbrain, and the cerebellum bilaterally. Behaviorally, the patients performed the tasks with equal success albeit more slowly. No animal-artefact differences emerged in the patients' activation patterns, indicating that their activation increases reflected a generalized, presumably compensatory reaction to higher task demands in the face of a progressive neurological disease.

Aged↗
PubMed2003

Minor gland and whole saliva in postmenopausal women using a low potency oestrogen (oestriol).

Many women undergo hormone replacement therapy in order to relieve menopausal and postmenopausal symptoms. Oral discomfort is common among these symptoms and studies have shown that the stimulated whole saliva flow rate is increased after combined oestradiol and progesterone replacement therapy. There is, however, no data regarding the effect of other oestrogens or of oestrogen alone on whole and minor gland saliva. In the present study, the flow rate from minor salivary glands (buccal, labial and palatal) and the secretion rate and buffer capacity of whole saliva was examined in 18 postmenopausal women (61-76 years) prior to, and during 1 year of a low potency oestrogen (oestriol) use. The ability of whole saliva to aggregate and mediate bacterial adherence as well as subjective feelings of dry mouth was also examined. For comparison, the same variables were examined in nine peri- and postmenopausal, non-medicated women (reference group, 53-61 years). During hormone treatment, the labial saliva flow was significantly increased and the complaints of dry mouth reduced. Increased stimulated whole saliva flow was seen in both the hormone and reference groups. This was also true for the stimulated whole saliva buffer capacity, which was increased parallel to the flow rate. The secretion rates were generally lower in the hormone group compared to the reference group throughout the study period. Except for stimulated whole saliva, statistical analysis at baseline revealed no age-related reduction of the saliva flow rates. The ability of whole saliva to mediate aggregation of Actinomyces naeslundii was significantly decreased after hormone treatment. Thus, the present findings indicate that a low dose oestrogen (oestriol) may affect the flow rate of labial salivary glands and the bacterial aggregation activity of whole saliva.

Aged↗
PubMed2003

Age, education and test performance on the Finnish CERAD.

OBJECTIVES: The purpose of this study was to clarify the effects of age and education on CERAD (Consortium to Establish a Registry for Alzheimer's Disease) test performances. MATERIAL AND METHODS: We present preliminary data on CERAD test results for a sample of elderly normal Finns (n = 40, age 58-85 years). RESULTS: Our results show no significant correlation between age and CERAD test results. Significant differences were found between subjects with low versus high education in nine CERAD test scores. The mean scores in the low-education group were near the cut-off point in the naming test, whereas the mean scores of the high-education group nearly reached the ceiling on six test scores. These differences were evident in the wordlist learning test, which has previously been argued to be unaffected by educational level. Savings scores were unaffected by education. CONCLUSION: The results underline the importance of taking into account the educational level of persons with subjective memory complaints when screening with CERAD for mild cognitive impairment and preclinical Alzheimer's disease.

Age Factors↗
PubMed2003

Hippocampal dopamine D2 receptors correlate with memory functions in Alzheimer's disease.

Post mortem studies have revealed a loss of dopamine D2 receptors in the temporal lobes in Alzheimer's disease (AD). Moreover, the role of hippocampal D2 receptors on memory performance has been suggested in experimental studies. However, there are no previous in vivo studies on extrastriatal D2 receptors in AD. Our aim was to examine in vivo whether hippocampal or temporal cortical dopamine D2 receptors are affected in AD and whether D2 receptor availability is associated with the memory dysfunction seen in AD. Fourteen patients with probable AD and 11 age- and sex-matched controls were studied with positron emission tomography using a dopamine D2/D3 receptor antagonist [(11)C]FLB 457. The D2 receptor binding potentials (BPs) were measured in extrastriatal brain regions and a neuropsychological investigation was performed on the patients with AD. In AD, the D2 receptor availability was reduced in the hippocampus: by 34% (P = 0.03) in the right hippocampus and by 14% (P = 0.78) in the left hippocampus as compared with controls. Multiple linear regression analysis showed that the BP in the right hippocampus had a significant positive association with verbal memory performance (Wechsler Memory Scale - Revised) (P = 0.001) and picture naming (the Boston Naming Test) (P = 0.002). Our findings suggest a role for temporal lobe D2 receptors in the memory and naming performance in AD, and suggest that studies to evaluate the efficiency of dopaminergic medication on patients with early AD might be warranted.

Aged↗
PubMed2003

The prevalence of antibodies against Sindbis-related (Pogosta) virus in different parts of Finland.

OBJECTIVE: To study the occurrence of Sindbis-related (Pogosta) disease in Finland by serological means. METHODS: A total of 2250 serum samples from five different areas were included in the study. Four hundred samples were collected from healthy blood donors and 1850 samples from patients who were suspected to have some viral infection. Antibodies of IgG and IgM classes against Pogosta virus were measured. RESULTS: Eleven per cent of 2250 samples were positive for IgG and 0.6% were positive for IgM class antibodies against Pogosta virus. The antibody prevalence in Finland was almost equally distributed, being highest in western Finland (17%) and lowest in southern and northern Finland (9%). Of all samples with IgG class antibodies, 25% were taken from children under 10 yr of age. CONCLUSIONS: The prevalence of antibodies against Pogosta virus was much higher than we expected. Additionally, they were detected from all locations studied and not only in eastern Finland, which has been thought to be the main endemic area for this disease. Pogosta disease has been considered to affect mainly middle-aged persons, but our results indicate a high prevalence also among children.

Adolescent↗
PubMed2002

Striatal dopamine transporter and extrapyramidal symptoms in frontotemporal dementia.

OBJECTIVE: To evaluate dopaminergic function in patients with frontotemporal dementia (FTD). BACKGROUND: Patients with FTD not only show typical behavioral and cognitive deficits but extrapyramidal symptoms, most commonly rigidity and akinesia. The pathophysiologic basis of these symptoms is unclear. METHODS: The authors investigated 12 patients (mean age = 67.2 +/- 7.2 years, range = 52 to 76 years) with FTD using a cocaine analogue [11C]CFT as a ligand with PET. The results were compared with those of 15 healthy control subjects (mean age = 49.7 years, range = 23 to 70 years) using analysis of covariance to adjust for difference in age. A dynamic 80-minute study was performed, and (region - cerebellum)/cerebellum ratios were calculated for the caudate nucleus and putamen. The severity of extrapyramidal symptoms was evaluated by the motor part of the Unified Parkinson's Disease Rating Scale (UPDRS). RESULTS: The mean age-adjusted [11C]CFT uptake value in the putamen in patients with FTD was reduced to 82% of the control value (p = 0.017), with the corresponding figure for caudate [11C]CFT uptake being 86% (p = 0.007). The motor UPDRS scores of patients with FTD showed a negative correlation with [11C]CFT uptake in both the putamen (r = -0.76, p = 0.004) and caudate nucleus (r = -0.70, p = 0.01). CONCLUSIONS: Nigrostriatal dopaminergic function is impaired in FTD, with the projections to the putamen and caudate nucleus being affected to the same degree. The reduction in the binding of the dopamine transporter ligand [11C]CFT is related to the severity of extrapyramidal symptoms of the patients.

Adult↗
PubMed2001

Molecular pathogenesis of a disease: structural consequences of aspartylglucosaminuria mutations.

A deficiency of functional aspartylglucosaminidase (AGA) causes a lysosomal storage disease, aspartylglucosaminuria (AGU). The recessively inherited disease is enriched in the Finnish population, where 98% of AGU alleles contain one founder mutation, AGU(Fin). Elsewhere in the world, we and others have described 18 different sporadic AGU mutations. Many of these are predicted to interfere with the complex intracellular maturation and processing of the AGA polypeptide. Proper initial folding of AGA in the endoplasmic reticulum (ER) is dependent on intramolecular disulfide bridge formation and dimerization of two precursor polypeptides. The subsequent activation of AGA occurs autocatalytically in the ER and the protein is transported via the Golgi to the lysosomal compartment using the mannose-6-phosphate receptor pathway. Here we use the three-dimensional structure of AGA to predict structural consequences of AGU mutations, including six novel mutations, and make an effort to characterize every known disease mutation by dissecting the effect of mutations on intracellular stability, maturation, transport and the activity of AGA. Most mutations are substitutions replacing the original amino acid with a bulkier residue. Mutations of the dimer interface prevent dimerization in the ER, whereas active site mutations not only destroy the activity but also affect maturation of the precursor. Depending on their effects on the AGA polypeptide the mutations can be categorized as mild, moderate or severe. These data contribute to the expanding body of knowledge pertaining to molecular pathogenesis of AGU.

Amino Acid Sequence↗
PubMed2001

Resumming Long-Distance Contributions to the QCD Pressure.

The strict coupling constant expansion for the free energy of hot QCD plasma shows bad convergence at all reasonable temperatures, and does not agree well with its 4D lattice determination. This has recently led to various refined resummations, whereby the agreement with the lattice result should improve, at the cost of a loss of a formal agreement with the coupling constant expansion and particularly with its large infrared sensitive "long-distance" contributions. We show here how to resum the dominant long-distance effects by using a 3D effective field theory, and determine their magnitude by simple lattice Monte Carlo simulations.

Journal Article↗
PubMed2001

GSM phone signal does not produce subjective symptoms.

The influence of pulsed radiofrequency (RF) electromagnetic fields of digital GSM mobile phones (902 MHz, 217 Hz pulse modulation) on subjective symptoms or sensations in healthy subjects were studied in two single-blind experiments. The duration of the RF exposure was about 60 min in Experiment 1 and 30 min in Experiment 2. Each subject rated symptoms or sensations in the beginning of the experimental session and at the end of both the exposure and the nonexposure conditions. The symptoms rated were headache, dizziness, fatigue, itching or tingling of the skin, redness on the skin, and sensations of warmth on the skin. The results did not reveal any differences between exposure and non-exposure conditions, suggesting that a 30-60 min exposure to this RF field does not produce subjective symptoms in humans.

Adolescent↗