Publications by authors named "Usenius J"

Exercise is thought to increase the diameter of the conduit arteries supplying the muscles involved. We studied the effects of a physically active vs inactive lifestyle on artery diameters in monozygotic (MZ) twin pairs discordant over 30 years for leisure-time physical activity habits. In a population-based co-twin control study design, six middle-aged (50-65 years) same-sex MZ twin pairs with long-term discordance for physical activity were comprehensively identified from the Finnish Twin Cohort (TWINACTIVE study).

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Background And Objective: Exercise is thought to reduce high-risk body fat, but intervention studies are frequently limited by short follow-ups and observational studies by genetic selection. Therefore, we studied the effects of a physically inactive vs active lifestyle on high-risk (visceral, liver and intramuscular) fat in twin pairs discordant for leisure-time physical activity habits for over 30 years.

Design: A longitudinal population-based twin study.

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We examined the relationships between morphology and muscle-tendon dynamics of the quadriceps femoris muscle of 11 men using velocity-encoded phase-contrast magnetic resonance imaging (MRI). Thigh muscle electromyography and joint range of motion were first measured outside the MRI scanner during knee extension-flexion tasks that were performed at a rate of 40 times/min with elastic bands providing peak resistance of 5.2 kp (SD 0.

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Current methods of clinical assessment of muscle coordination and function after stroke do not provide information on deep muscles. The objective of this study was to examine how stroke affects both superficial and deep muscles' coordination and whether muscle function improves after rehabilitation. Muscle function, coordination, and activity of quadriceps femoris (QF) and hamstrings were evaluated in 10 stroke patients with mild hemiparesis and in 6 controls using velocity-encoded cine phase-contrast magnetic resonance imaging (VE-PC MRI), surface electromyography (sEMG), and maximal voluntary isometric contraction torque (MVC).

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Cosmetic breast implants have become increasingly popular throughout the world. However, there is insufficient knowledge about the frequency and severity of local complications such as rupture and capsular contracture. A pilot study of 25 Finnish women with 50 cosmetic breast implants was organized to determine the feasibility of conducting a magnetic resonance imaging (MRI)-based study of rupture incidence.

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Blood oxygenation level-dependent (BOLD) magnetic resonance imaging (MRI) has been recently used to quantify cerebral blood volume (CBV) and oxygen extraction ratio (OER). In the present study, we have exploited the intravascular BOLD model to assess gray matter (GM) OER at hemispheric level using parenchymal T(2) and CBV data at 1.5 T, obtained by single spin echo and dynamic susceptibility contrast (DSC) perfusion MRI, respectively.

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Objective: In this experimental study, we wanted to evaluate the informative value of dynamic magnetic resonance imaging in pelvic floor anatomy during pelvic floor muscle contractions in asymptomatic women and women with urinary continence dysfunction.

Study Design: Eight outpatients with stress urinary symptoms and eight asymptomatic women were scanned with a 1.5 T GE Signa CV/i high-speed scanner with real time fluorescopic imaging possibilities.

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The characteristics of blood oxygenation level-dependent (BOLD) fMRI and magnetoencephalographic (MEG) responses to vibrotactile stimuli in humans were studied and compared. The stimuli, presented with interstimulus intervals (ISIs) ranging from 1 to 5 s, yielded highly reproducible MEG responses, with current dipoles in the primary somatosensory (SI) cortex in all subjects. BOLD fMRI responses to similar stimuli showed substantial intrasubject variation in the activation sites around the SI cortex.

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Objectives: To investigate the consequences of rally driving on lumbar degenerative changes.

Background: Vehicular driving is suspected to accelerate disc degeneration through whole-body vibration, leading to back problems. However, in an earlier well-controlled study of lumbar MRI findings in monozygotic twins, significant effects of lifetime driving on disc degeneration were not demonstrated.

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A real-time automated way of quantifying metabolites from in vivo NMR spectra using an artificial neural network (ANN) analysis is presented. The spectral training and test sets for ANN containing peaks at the chemical shift ranges resembling long echo time proton NMR spectra from human brain were simulated. The performance of the ANN constructed was compared with an established lineshape fitting (LF) analysis using both simulated and experimental spectral data as inputs.

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We present a novel method to integrate in vivo nuclear magnetic resonance spectroscopy (MRS) information into the clinical diagnosis of brain tumours. Water-suppressed 1H MRS data were collected from 33 patients with brain tumours and 28 healthy controls in vivo. The data were treated in the time domain for removal of residual water and a region from the frequency domain (from 3.

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We describe a young woman who developed left ventricular failure and pulmonary edema during fulminant onset of multiple sclerosis. One of the numerous plaques was located in the left inferior cerebellar peduncle near the dorsal motor vagal and solitary tract nuclei. Within two days pulmonary edema had cleared, and within three days left ventricular function was normal.

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Purpose: External radiation therapy for brain tumors exposes healthy areas of brain to considerable doses of radiation. This may cause cognitive and psychological impairment, which indicate neuronal dysfunction. 1H-magnetic resonance spectroscopy (MRS) was used to study brain metabolites in the adjacent regions 0.

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We present here a combination of time-domain signal analysis procedures for quantification of human brain in vivo 1H NMR spectroscopy (MRS) data. The method is based on a separate removal of a residual water resonance followed by a frequency-selective time-domain line-shape fitting analysis of metabolite signals. Calculation of absolute metabolite concentrations was based on the internal water concentration as a reference.

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Prophylactic efficacy and safety of a low molecular weight heparin (LMWH) and those of conventional unfractionated heparin (UH) were investigated in a randomized study. Totally, 167 consecutive patients undergoing total hip replacement were allocated to two groups. Patients in the LMWH-group (n = 83) received a fixed dose of enoxaparin 40 mg once daily, starting 12 hours preoperatively and continuing for 10 days.

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We have studied 14 patients with different grades of astrocytomas using 1H NMR spectroscopy in vivo. Typically, astrocytomas exhibited a low N-acetylaspartate peak, a prominent signal from choline group-containing compounds, and lactate in the 1H NMR spectra in vivo. The uncorrected choline/creatine + phosphocreatine peak area ratios were higher in tumors than in normal brain tissue.

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We used proton magnetic resonance spectroscopy (1H MRS) to determine concentrations of N-acetylaspartate (NAA), creatine and choline in vivo (63 MHz) and in vitro (400 MHz) in seven patients undergoing surgical treatment of intractable temporal lobe epilepsy (TLE). Nine healthy volunteers were used as controls for in vivo MRS. NAA concentrations in vivo on the ipsilateral and contralateral sides were 6.

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Objective: The aim of the present study was to investigate quantitative metabolite patterns in human brain tumors by 1H nuclear MR spectroscopy (1H MRS).

Materials And Methods: Single voxel 1H MRS was used in studying metabolites in 23 primary brain tumors in vivo. The T2 relaxation times and saturation factors were determined for N-acetylaspartate (NAA), total creatine (Cr), choline-containing compounds (Cho), and water, which was used as an internal standard in computations of metabolite concentrations in vivo.

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Autologous (149 patients) and heterologous (101 patients) bone grafts were used for fusion in 250 patients with anterior cervical surgery. A stable fusion was achieved in 98% of patients in both groups and there was no significant difference in the clinical outcome. Donor site complications (severe pain, haematoma) were seen in one sixth of the patients with autologous bone grafts.

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A total of 135 patients with a fresh tibial shaft fracture and with no other significant injuries underwent primary conservative treatment. Data on their smoking habits were obtained from hospital records and by questionnaire. Although the smokers had better prospects for healing of the fracture at the outset than non-smokers (lower mean age and less fractures caused by high-energy injuries), the smokers were found to have a significantly longer mean time to clinical union and a higher incidence of delayed union.

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We report the first patient in Finland and Scandinavia with a deficiency of adenine phosphoribosyltransferase (APRT). About 30 clinically affected patients have been reported in the literature. APRT deficiency is an enzyme disorder which is inherited autosomally in a recessive manner.

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