PubMed Health⌕ Search

Biomedical subjects

K Salminen

Publications and source records attributed to K Salminen.

At least 19 recordsLinked to original sources
PubMed2002

High oxidized LDL and elevated plasma homocysteine contribute to the early reduction of myocardial flow reserve in healthy adults.

BACKGROUND: Impairment of coronary blood flow reserve has been shown to be an early manifestation of atherosclerosis and coronary artery disease (CAD). We studied more closely the contribution of various risk factors on early deterioration of coronary function. MATERIALS AND METHODS: Fifty-one young, apparently healthy adults, with normal or mildly elevated serum cholesterol levels but without other major risk factors for CAD, such as diabetes or hypertension, underwent positron emission tomography (PET) studies. Coronary flow reserve (CFR) was measured using O15-water. In addition to the classical risk factors, the role of several new risk indicators, such as low-density lipoprotein (LDL) oxidation, infection (Chlamydia pneumoniae antibodies), and inflammation parameters (adhesion molecules, ICAM, VCAM, selectin, and C-reactive protein), homocysteine and body iron stores were investigated. RESULTS: Elevated lipid and lipoprotein levels were not associated with reduced coronary reactivity. However, high autoantibody titers against oxidized LDL (oxLDL) were associated with 21% lower CFR than low oxLDL (P < 0.05). Furthermore, high homocysteine levels predicted low CFR (P < 0.05). The other measured parameters, Chlamydia pneumoniae antibody levels, C-reactive protein and adhesion molecule concentrations did not associate with myocardial blood flow. In a stepwise regression model, oxLDL (P = 0.03), homocysteine (P = 0.04) and triglycerides (P = 0.018) were significant predictors of CFR. CONCLUSIONS: The present study suggests an important role for oxidized LDL and plasma homocysteine on early impairment of coronary reactivity in young adults.

Adenosine↗
PubMed2000

Enterovirus RNA in serum is a risk factor for beta-cell autoimmunity and clinical type 1 diabetes: a prospective study. Childhood Diabetes in Finland (DiMe) Study Group.

Recent prospective studies have documented serologically an increased frequency of enterovirus infections in prediabetic children, indicating that these infections may initiate and accelerate the beta-cell damaging process several years before the clinical manifestation of type 1 diabetes. The aim of the present study was to establish whether these serological findings would be supported by the detection of enterovirus RNA in a unique prospective series of sera collected from prediabetic children 0-10 years before the manifestation of clinical type 1 diabetes. Reverse transcription followed by polymerase chain reaction employing highly conserved primers among enteroviruses were used to amplify enteroviral sequences. Viral RNA was found in 22% (11/49) of follow-up samples from prediabetic children but in only 2% (2/105) of those from controls (OR 14.9, P < 0.001). Persisting RNA positivity was not observed in any of these children. The presence of enterovirus RNA was associated with concomitant increases in the levels of autoantibodies against islet cells (OR 21.7, P < 0.01) and glutamic acid decarboxylase (OR 15.4, P < 0.05), but not in the levels of antibodies against insulin or the tyrosine phosphatase-like IA-2 protein. In contrast to the prediabetic children, those with newly diagnosed type 1 diabetes were negative for enterovirus RNA. The results thus complement previous serological data, suggesting that enterovirus infections are an important risk factor underlying type 1 diabetes and associated with the induction of beta-cell autoimmunity even years before symptoms appear.

Adolescent↗
PubMed1999

Beta-lactamase production in Prevotella intermedia, Prevotella nigrescens, and Prevotella pallens genotypes and in vitro susceptibilities to selected antimicrobial agents.

The present study investigated the beta-lactamase production of 73 Prevotella intermedia, 84 Prevotella nigrescens, and 14 Prevotella pallens isolates and their in vitro susceptibilities to six antimicrobial agents. The P. intermedia and P. nigrescens isolates were recovered from oral and extraoral samples obtained from subjects in two geographic locations from 1985 to 1995. The clonality of the beta-lactamase-positive and beta-lactamase-negative isolates and the clustering of the genotypes were studied by arbitrarily primed-PCR fingerprinting. beta-Lactamase production was detected in 29% of P. intermedia isolates, 29% of P. nigrescens isolates, and 57% of P. pallens isolates. No difference in the frequencies of beta-lactamase production by P. intermedia and P. nigrescens between isolates from oral and extraoral sites, between isolates obtained at different time periods, or between P. intermedia isolates from different geographic locations was observed. However, the P. nigrescens isolates from the United States were significantly more frequently (P = 0.015) beta-lactamase positive than those from Finland. No association between the genotypes and beta-lactamase production or between the genotypes and the sources of the isolates was found. The penicillin G MICs at which 90% of the isolates were inhibited were 8 microg/ml for P. intermedia, 8 microg/ml for P. nigrescens, and 16 microg/ml for P. pallens. For the beta-lactamase-negative isolates, the corresponding values were 0.031, 0.031, and 0.125 microg/ml, and for the beta-lactamase-positive isolates, the corresponding values were 16, 8, and 32 microg/ml. All isolates were susceptible to amoxicillin-clavulanate, cefoxitin, metronidazole, azithromycin, and trovafloxacin. The MICs of amoxicillin-clavulanate and cefoxitin were relatively higher for the beta-lactamase-positive population than for the beta-lactamase-negative population.

Anti-Bacterial Agents↗
PubMed1999

beta-lactamase production and antimicrobial susceptibility of oral heterogeneous Fusobacterium nucleatum populations in young children.

Oral Fusobacterium nucleatum populations from 20 young, healthy children were examined for beta-lactamase production. Ten children (50%) harbored, altogether, 25 beta-lactamase-positive F. nucleatum isolates that were identified as F. nucleatum subsp. polymorphum, F. nucleatum subsp. nucleatum, and F. nucleatum subsp. vincentii (J. L. Dzink, M. T. Sheenan, and S. S. Socransky, Int. J. Syst. Bacteriol. 40:74-78, 1990). In vitro susceptibility of these beta-lactamase-producing and 26 non-beta-lactamase-producing F. nucleatum isolates was tested with penicillin G, amoxicillin-clavulanic acid, tetracycline hydrochloride, metronidazole, trovafloxacin, and azithromycin. Except for penicillin G, the antimicrobials exhibited good activity against all F. nucleatum isolates.

Amoxicillin-Potassium Clavulanate Combination↗
PubMed1999

Diagnosis of enterovirus and rhinovirus infections by RT-PCR and time-resolved fluorometry with lanthanide chelate labeled probes.

Detection of enteroviruses and rhinoviruses has traditionally been based on laborious and time-consuming virus isolation. Recently, rapid and sensitive assays for detecting enterovirus and rhinovirus genomic sequences by reverse transcription-polymerase chain reaction (RT-PCR) have been introduced. An RT-PCR assay is described that amplifies both enteroviral and rhinoviral sequences, followed by liquid-phase hybridization carried out in a microtiter plate format. In the hybridization assay, amplicons are identified by enterovirus- or rhinovirus-specific probes carrying lanthanide chelate labels, which can be detected simultaneously by time-resolved fluorometry. The sensitivity and specificity of the RT-PCR-hybridization method were evaluated with a representative collection of enteroviruses and rhinoviruses and tested further its applicability to the clinical setting with cerebrospinal fluid samples and nasopharyngeal aspirates. The RT-PCR assay amplified all enteroviruses and rhinoviruses tested, and all but one amplicon gave a positive result in the subsequent hybridization assay. The RT-PCR-hybridization method was more sensitive than virus isolation for the detection of enteroviruses and rhinoviruses in the clinical samples. High sensitivity, rapidity, and easy performance make the assay suitable for the routine diagnosis of enterovirus and rhinovirus infections.

Animals↗
PubMed1998

Functional food science and the cardiovascular system.

Cardiovascular disease has a multifactorial aetiology, as is illustrated by the existence of numerous risk indicators, many of which can be influenced by dietary means. It should be recalled, however, that only after a cause-and-effect relationship has been established between the disease and a given risk indicator (called a risk factor in that case), can modifying this factor be expected to affect disease morbidity and mortality. In this paper, effects of diet on cardiovascular risk are reviewed, with special emphasis on modification of the plasma lipoprotein profile and of hypertension. In addition, dietary influences on arterial thrombotic processes, immunological interactions, insulin resistance and hyperhomocysteinaemia are discussed. Dietary lipids are able to affect lipoprotein metabolism in a significant way, thereby modifying the risk of cardiovascular disease. However, more research is required concerning the possible interactions between the various dietary fatty acids, and between fatty acids and dietary cholesterol. In addition, more studies are needed with respect to the possible importance of the postprandial state. Although in the aetiology of hypertension the genetic component is definitely stronger than environmental factors, some benefit in terms of the development and coronary complications of atherosclerosis in hypertensive patients can be expected from fatty acids such as alpha-linolenic acid, eicosapentaenoic acid and docosahexaenoic acid. This particularly holds for those subjects where the hypertensive mechanism involves the formation of thromboxane A2 and/or alpha 1-adrenergic activities. However, large-scale trials are required to test this contention. Certain aspects of blood platelet function, blood coagulability, and fibrinolytic activity are associated with cardiovascular risk, but causality has been insufficiently proven. Nonetheless, well-designed intervention studies should be initiated to further evaluate such promising dietary components as the various n-3 and n-6 fatty acids and their combination, antioxidants, fibre, etc. for their effect on processes participating in arterial thrombus formation. Long-chain polyenes of the n-3 family and antioxidants can modify the activity of immunocompetent cells, but we are at an early stage of examining the role of immune function on the development of atherosclerotic plaques. Actually, there is little, if any, evidence that dietary modulation of immune system responses of cells participating in atherogenesis exerts beneficial effects. Although it seems feasible to modulate insulin sensitivity and subsequent cardiovascular risk factors by decreasing the total amount of dietary fat and increasing the proportion of polyunsaturated fatty acids, additional studies on the efficacy of specific fatty acids, dietary fibre, and low-energy diets, as well as on the mechanisms involved are required to understand the real function of these dietary components. Finally, dietary supplements containing folate and vitamins B6 and/or B12 should be tested for their potential to reduce cardiovascular risk by lowering the plasma level of homocysteine.

Blood Coagulation↗
PubMed1992

A double-blind, parallel-group comparison of flosequinan and enalapril in the treatment of chronic heart failure.

The effects of flosequinan and enalapril on exercise capacity (bicycle exercise duration), quality-of-life symptomatology (visual analogue scales) and New York Heart Association (NYHA) grading, were compared in 61 patients with chronic heart failure (NYHA, grade III). Bicycle exercise duration improved similarly with flosequinan (+27%) and enalapril (+18%); in patients completing the study, flosequinan produced a significantly greater increase in exercise time at week 12, compared with enalapril (P = 0.02). Improvements in visual analogue scores relating to general health, energy and vitality, ability to perform physical activities and breathing performance, were equivalent for both drugs. Changes in NYHA classification showed that 27 (55%) of 49 patients completing the study had improved by at least one NYHA grade (15 (68%) patients on flosequinan; 12 (44%) on enalapril). The overall safety and tolerability of the two treatments was similar; 18 patients reported adverse effects while on flosequinan, compared with 19 patients on enalapril. Neither treatment was associated with any clinically important changes in haematological or biochemical variables, although some treatment-related effects were observed. This study confirms that flosequinan achieved similar efficacy to enalapril in the symptomatic relief of chronic heart failure. The effect of flosequinan on survival in chronic heart failure has not been tested; pending such studies, our data suggest that it may prove a useful alternative therapy in patients where ACE inhibitors are contraindicated or poorly tolerated.

Adult↗
PubMed1988

Secretory morphology of the intermediate lobe of the rat pituitary incubated in vitro.

The ultrastructure of the incubated intermediate lobe of the rat pituitary and the morphological effect of isoproterenol stimulation on its cells were studied under in vitro conditions. The general structure of isolated neurointermediate lobes maintained for 2-3 h in vitro was well preserved, and the presence of intact nerve terminals establishing synaptic contacts with the glandular cells of the intermediate lobe was confirmed. Removal of the intermediate lobe from central inhibition leads to increased hormonal secretion, which was reflected by large Golgi areas and the appearance of secretory images. However, no obvious degranulation or peripheral migration of the secretory granules after 2-3 h in vitro was seen. The secretory granules varied in electron density; totally electron-lucent granules were regularly observed and exocytotic phenomena were shown. In addition, more extensive invaginations suggesting secretion by compound exocytosis were seen. A three-fold increase in the beta-endorphin secretion during a 4-min stimulation with 10(-6) M isoproterenol did not induce any morphometrically detectable changes in the incubated cells. This indicates that only a minor fraction of the total granule content is mobilized during an acute increase in secretory activity.

Animals↗
PubMed1988

Response of plasma endorphins, prolactin and catecholamines in women to intense heat in a sauna.

Concentrations of immunoreactive beta-endorphin (ir beta-E), corticotropin, cortisol, prolactin and catecholamines in plasma were followed in 11 healthy women during and after exposure to intense heat in a Finnish sauna bath, and compared to those in a similar control situation without exposure to heat. Heat stress significantly increased prolactin and norepinephrine secretion; the percentage increases from the initial plasma concentrations varied from 113 to 1280% (mean 510%) and from 18 to 150% (mean 86%), respectively. The response of the plasma levels of epinephrine, ir beta-E, corticotropin and cortisol to heat exposure was variable. Compared to the control situation, no statistically significant effect of heat exposure on the plasma levels of these hormones was found.

Adrenocorticotropic Hormone↗