553 Hits in 1.7 sec

Sonography and MRI in the evaluation of painful arthritic shoulder

E. Alasaarela, R. Takalo, O. Tervonen, M. Hakala, I. Suramo
1997 Rheumatology  
We evaluated 31 painful shoulders of 30 patients with chronic arthritis by ultrasonography (US) and compared the results with those of magnetic resonance imaging (MRI). Both US and MRI revealed effusion in the subacromial-subdeltoid (SA-SD) bursa, biceps tendon sheath (BTS) and glenohumeral (GH) joint, but MRI was more accurate in depicting joint inflammation because of its ability to visualize synovial hypertrophy. US visualized biceps tendon ruptures equally well as MRI. MRI was better able
more » ... reveal full-thickness tear of the supraspinatus tendon, whereas US showed better other changes of the supraspinatus tendon (degeneration or partial-thickness tear). Both of the imaging methods were able to depict erosions of the humeral head, but the locations occasionally differed. Inexpensive and easily available US can be recommended as the first imaging method for the detection of soft-tissue changes in the arthritic shoulder, but in rotator cuff problems both methods may be needed.
doi:10.1093/rheumatology/36.9.996 pmid:9376998 fatcat:rv5rvul2yrhpbdukk5jmolh73u

The teleradiology system and changes in work practices

H Karasti, J Reponen, O Tervonen, K Kuutti
1998 Computer Methods and Programs in Biomedicine  
After the design and development of the teleradiology system, a work practice oriented approach was used to gain a more holistic understanding of the relationship between the emerging work practice and the newly implemented technology, and to provide information for redesigning the system. The approach which utilized ethnographically informed fieldwork and cooperative workshops was introduced. Cooperation, the chain of tasks, and articulation work of teleradiology work practice were described,
more » ... ith the focus on image interpretation in particular. From the point of view of radiologists' image interpretation work, a report was made on how these findings influenced the evaluation and redesign of the system. Furthermore, the problematics of distributed collaboration, reorganization of work, and education are emphasized.
doi:10.1016/s0169-2607(98)00047-9 pmid:9804001 fatcat:b44iqgjvrjgqjl3wrvszxbp36u

Circumferential measurement of thoracic wall using a standard respiratory belt

E. Rauvala, L. Jyrkinen, A. Koivula, K. Suominen, O. Tervonen
1996 Journal of digital imaging  
Respiratory gating during imaging to reduce imaging artifacts involves the gathering of image data only at the end of the respiratory cycle. This is commonly performed by a pneumatic respiratory belt to monitor thoracic wall motion during respiration. Such gating has been used for magnetic resonance, computerized tomographic, and nuclear medicine imaging. The goal of this study was to measure the performance of a standard belt used for gating imaging studies. The standard respiratory belt
more » ... provided with the Magnetom 42 SP MRI scanner (Siemens AG, Erlangen, Germany) was selected. The belt was connected to a microcontroller-based pressure measurement unit that was connected to the standard RS-232C serial port of a computer. The signal was compared with that of a strain gauge respiration transducer. The response of the system was tested in vitro both for isometric and isotonic Ioading. The data measured from the pneumatic belt was linear with different weights of 50 to 1,400 grams with a coefficient of determination (R 2) of 0.999. The system was linear for different amounts of stretching (R 2 of 0.998) within the first 45 mm, which is enough for normal breathing. In vivo the pneumatic system seemed more accurate in measuring the constant stretching in apnea than the strain gauge respiratory belt. The results show that it is possible to use a standard pneumatic belt for accurate measurement of thoracic wall movement during imaging and for other purposes as well.
doi:10.1007/bf03168860 pmid:8734577 fatcat:32hev3lsx5crzp4ga4cbvisezy

Temperature has a major influence on cardiac natriuretic peptide in salmon

V. Tervonen, K. Kokkonen, H. Vierimaa, H. Ruskoaho, O. Vuolteenaho
2001 Journal of Physiology  
Tervonen & O. Vuolteenaho, unpublished results) . Due to the fragility of the tissue, however, the atrial preparation is much more awkward to use than the ventricular preparation.  ...  Tervonen and others 204 J. Physiol. 536.1 Figure 5 .  ... 
doi:10.1111/j.1469-7793.2001.00199.x pmid:11579169 fatcat:7kdgix3a4bfdlnvritmzbujykm

Structural dynamics of tight junctions modulate the properties of the epithelial barrier

Aapo Tervonen, Teemu O. Ihalainen, Soile Nymark, Jari Hyttinen, Michael Koval
2019 PLoS ONE  
[33] was considerably smaller than the originally measured values (460 vs. 5650 O cm 2 ) [84] .  ...  The obtained TER values for these cell radii of 15 and 20 μm were 4820 and 7310 O cm 2 , respectively.  ...  Writing -original draft: Aapo Tervonen. Writing -review & editing: Aapo Tervonen, Teemu O. Ihalainen, Soile Nymark, Jari Hyttinen.  ... 
doi:10.1371/journal.pone.0214876 pmid:30964903 pmcid:PMC6456171 fatcat:wcsqzw4warc7jmk7bznro5hx5u

Non-invasive semi-quantitative and quantitative ultrasonography findings in knee osteoarthritis: preliminary study

J. Podlipská, J.M. Koski, E. Liukkonen, O. Tervonen, J. Arokoski, S. Saarakkala
2014 Osteoarthritis and Cartilage  
Liukkonen x, O. Tervonen x , y, J. Arokoski k, S. Saarakkala y , x. y Univ. of Oulu, Oulu, Finland; z Mikkeli Central Hosp., Mikkeli, Finland; x Oulu Univ. Hosp., Oulu, Finland; k Kuopio Univ.  ... 
doi:10.1016/j.joca.2014.02.519 fatcat:fq2hla3qf5c7tnnsktqzmzlnp4

Topographical variation of T2 relaxation time in the young adult knee cartilage at 1.5T

I. Hannila, S. Susanna Räinä, O. Tervonen, R. Ojala, M.T. Nieminen
2009 Osteoarthritis and Cartilage  
Objective: To assess the normal topographical variation of T2 relaxation time of articular cartilage in different compartments of the knee joint and at different tissue depths in young healthy adults. Methods: Twenty asymptomatic young adult volunteers (age range, 21e27 years; mean age, 22.5 years), were studied at 1.5 T. Both axial and sagittal multi-slice multi-echo spin echo measurements were performed to determine the T2 relaxation time of cartilage in the femoral, tibial and patellar
more » ... tments. The cartilage surfaces were divided into 24 segments and each segment was divided into deep and superficial regions-of-interest (ROIs) of equal thickness. The reproducibility for ROI analysis was assessed for five patients by determining the interclass correlation coefficient (ICC) and the root-mean-square coefficient of variation (CV RMS ). Results: Cartilage T2 was significantly dependent on joint topography, compartment and tissue depth. For all joint surfaces, superficial T2 values were systematically higher as compared to deep tissue. The data showed a trend toward higher T2 values at the load bearing area of the femoral condyles. The interobserver error varied significantly among different locations and showed mostly good reproducibility with mean ICC of 0.70 and a CV RMS of 5.0%. Conclusion: The normal variation in cartilage T2 within a joint is significant and should be acknowledged when pathology-related T2 changes are investigated. The knowledge on normal variation can be used for power and sample size calculations in further studies, and the T2 values as control data in future patient studies.
doi:10.1016/j.joca.2009.05.011 pmid:19501682 fatcat:rohzmpxnk5b77kzf2hpjjhqisq

Characteristics of first-time varenicline users – A cross-sectional study in Finnish quitters

Hanna E. Tervonen, Juha H. O. Turunen, Christine L. Baker, Juha Laine, Kari Linden
2017 BMC Public Health  
Varenicline is an efficacious medicine for smoking cessation (SC) but little is known about the characteristics of varenicline users. This study examined the characteristics of first-time (naïve) varenicline users in Finland and compared those who had previously used SC pharmacotherapy to those who were trying SC pharmacotherapy for the first time. Methods: A cross-sectional survey was conducted in Finnish community pharmacies between February 2014 and January 2015. Pharmacy customers
more » ... a varenicline starter package for the first time ever were asked to complete a questionnaire or to participate in a structured interview conducted by the pharmacist (identical questions). The questionnaire included questions about demographic characteristics, smoking habits, previous cessation attempts and factors associated with varenicline use. Results: Altogether 98 people completed the survey. The majority were daily smokers (96%, n = 94), with a history of over 10 years of regular smoking (94%, n = 92), and a strong/very strong nicotine dependence (67%, n = 66). Half of the participants (54%, n = 53) were trying a SC pharmacotherapy for the first time. Demographic characteristics and smoking habits were similar between first-time and previous users of SC medications (p > 0.05). Health centers (42%, n = 41) and occupational health care clinics (37%, n = 36) were the most common sources of varenicline prescriptions. The majority of participants received the prescription for varenicline after mentioning their desire for quitting to a physician (70%, n = 69). Conclusions: Considering the relatively large proportion of SC naïve medicine users among new users of varenicline, smokers who have previously been reluctant to quit smoking, to use other pharmacological SC interventions, or perhaps unaware of these options may be interested in attempting cessation with varenicline. Most participants made the initiative to discuss their smoking with the physician, which led to varenicline prescribing. This suggests that physicians may not satisfactorily recognize their patients' nicotine dependence and desire to quit, and they should more actively support patients' smoking cessation.
doi:10.1186/s12889-017-4248-1 pmid:28420395 pmcid:PMC5395864 fatcat:tdxwwitpvbbjfcjtzxaxm3yfqi

Parents' received and expected information about their child's radiation exposure during radiographic examinations

Heljä T Oikarinen, Anne M Perttu, Helena M Mahajan, Leila H Ukkola, Osmo A Tervonen, Aino-Liisa I Jussila, Anja O Henner
2018 Pediatric Radiology  
Despite regulations, insufficient information is provided to adult patients prior to their radiologic examinations. Information regarding paediatric patients has not been systematically studied. To survey parents' experience and wishes for information in connection with their child's radiographic examination. We provided a questionnaire to consenting parents of children younger than 12 years old at a university hospital. The questionnaire asked parents about the information obtained from the
more » ... errer prior to the radiograph, the chance to discuss with the referrer and their wishes regarding future information. Forty-one parents responded to the survey. Twenty-five children were referred for radiography of extremities, the others for dental, body and skull examinations. Altogether 34/41 (83%, 95% confidence interval [CI] 69-91%) parents said they received adequate information on the purpose of the examination, 8/35 (23%, 95% CI 12-39%) on other options and 3/41 (7%, 95% CI 3-19%) on radiation dose. Ten of 41 parents (24%, 95% CI 12-40%) said they were aware of radiation exposure. The number of previous radiology examinations was not sufficiently discussed. The communication was scored as mean 6.5 (95% CI 5.8-7.1) on a scale from 4 (poor) to 10 (excellent). Thirty-eight of 40 (95%, 95% CI 84-99%) of parents expected information on the purpose, 35/40 (88%, 95% CI 74-95%) on radiation dose and 31/40 (78%, 95% CI 63-88%) on other options. Symbols of radiation and corresponding period of natural background radiation are preferred to convey the dose. A referrer is the preferred source of information. Parents did not feel adequately informed prior to their child's radiographic examination. Parents expect more information about the purpose, dose and alternative tests.
doi:10.1007/s00247-018-4300-z pmid:30426180 pmcid:PMC6334726 fatcat:fzenrtjlwncp7kwwjb2v2q5vge

Justification of CT examinations in young adults and children can be improved by education, guideline implementation and increased MRI capacity

P Tahvonen, H Oikarinen, E Pääkkö, A Karttunen, R Blanco Sequeiros, O Tervonen
2013 British Journal of Radiology  
Objective: To determine whether the justification of CT examinations performed on young patients can be improved by various interventions and whether these have an effect on the total number of CTs performed. Methods: Specific interventions-education, guideline implementation and increased MRI capacity-were introduced at the Oulu University Hospital, Oulu, Finland, following a previous study demonstrating unjustified use of CT examination in young patients. In the present study, the
more » ... n of 177 CT examinations of the lumbar and cervical spine, head, abdomen, nasal sinuses and trauma performed on patients aged under 35 years in 2009 was analysed retrospectively by looking at requests and corresponding patient files. The indications of the examinations were compared with the referral guidelines recommended by the European Commission. Results from our previously published similar study carried out before the interventions were used as a reference.
doi:10.1259/bjr.20130337 pmid:23934962 pmcid:PMC3755402 fatcat:knxvz65ozvesxifln6z3myy7hm

Par6G suppresses cell proliferation and is targeted by loss-of-function mutations in multiple cancers

E Marques, J I Englund, T A Tervonen, E Virkunen, M Laakso, M Myllynen, A Mäkelä, M Ahvenainen, T Lepikhova, O Monni, S Hautaniemi, J Klefström
2015 Oncogene  
D 3 s h R H O A s h N U M B -A s h M O E S I N s h T S C 2 s h E Z R I N s h C D C 4 2 -B s h P A R D 6 B s h P A R Growth control Synthetic lethal Cell cycle  ...  ErbB2 challenged MCF10A Ki67 % (Fold change) Proliferative activity (d18 acinar structures) (Myc ON relative to Myc OFF) 2 1.8 1 0.8 s h S c r a s h M P P 5 -A s h M P P 5 -B s h T M O  ... 
doi:10.1038/onc.2015.196 pmid:26073086 pmcid:PMC4800288 fatcat:sjnfwg64pjfn7hdywkrpgugmce

In vivo quantification of delayed gadolinium enhancement in the nucleus pulposus of human intervertebral disc

Jaakko L. Niinimäki, Outi Parviainen, Jyrki Ruohonen, Risto O. Ojala, Mauno Kurunlahti, Jaro Karppinen, Osmo Tervonen, Miika T. Nieminen
2006 Journal of Magnetic Resonance Imaging  
INTRODUCTION Diffusion through the end plates is the primary nutritional pathway of intervertebral disks. Deterioration of this pathway is known to be an important factor in the process of disk degeneration [1] Transfer of nutrients through the end plate can be simulated in vivo by measuring transfer of intravenously administered paramagnetic contrast agent into the nucleus pulposus of intervertebral disk from circulation. Previous animal and human studies have investigated disk enhancement
more » ... g paramagnetic contrast agents [2] [3] [4] [5] , however, these studies have only assessed signal intensity changes. The present study was conducted to quantify the delayed enhancement of the nucleus pulposus in vivo using a non-ionic contrast agent and T1 relaxation time measurements before and after contrast agent injection. Finally, the quantitative enhancement data were correlated with the Pfirrmann visual grading of disk degeneration [6] . METHODS Twenty male volunteers (mean age 49±5, range 40-55 ) were studied. A routine spine examination was conducted at 1.5T (two GE Signa 1.5T scanners, Milwaukee, WI), including T2-weighted sagittal images, that were used to score the intervertebral disk degeneration according to the Pfirrmann grading [6] . For T1 relaxation time measurements of intervertebral disks (between L1 and S1 vertebrae) a series of sagittal single slice inversion recovery measurements were conducted (TR=3400ms, TI=100, 200, 400, 800, 1600 and 3200ms, 4-mm slice thickness, in-plane resolution of 0.78mm). This was followed by an intravenous injection of 0.2mM/kg of non-ionic GdDTPA-DMA (Omniscan, Amersham Health AS, Oslo, Norway) and a T1 measurement series 90min after the injection. For each disk, T1 relaxation times were averaged from elliptical regions of interest (45±4mm 2 ) that were manually segmented into the nucleus pulposus. RESULTS Altogether 93 disks were analyzed. A statistically significant decrease in T1 relaxation time of nucleus pulposus was observed as a result of contrast agent intake (Wilcoxon signed ranks test, p<0.0001) ( Fig. 1 and 2) , the percentual change of T1 relaxation time for individual disks ranging between 0 and 60%. The T1 relaxation times varied between 440-980ms (mean 780 ± 120ms) and 350-940ms (690 ± 160ms) before and after the injection, respectively. A positive trend was observed between the change in the T1 relaxation rate (∆R1) and the Pfirrmann grading of disk degeneration (Fig. 3) . A statistically significant difference in ∆R1 was observed between samples in all Phirrmann grades except between grades II and III (Mann-Whitney U test, p<0.0001-0.02). DISCUSSION For a single compartment model the change in the R1 relaxivity rate (∆R1) is directly proportional to the contrast agent concentration within the pulposus if a constant relaxivity (R) is assumed, i.e. [GdDTPA-BMA] = R ∆R1. Absolute concentrations could be estimated if relaxivity of the gadolinium complex in the disk was known. A previous study suggests that the relaxivity between the pulposus and annulus may be different [7] . Since there is considerable variation in the T1 relaxation time without contrast agent it may not be possible to quantify the enhancement without a T1 measurement prior to contrast agent administration. Contrast agent intake is a dynamic process which is likely to depend on the nutritional pathway (blood vessels -vertebral sinusoids -endplate -annulus fibrosusnucleus pulposus) and the diffusional properties of these tissues. A previous study reported a decreased enhancement (signal intensity change) in degenerated disks minutes after contrast agent injection. The present results with a longer delay are not consistent with this finding, and it is anticipated that a longer delay may be less sensitive to short time-scale differences in contrast agent intake between normal and degenerated disks. Further studies are necessary to understand the observed relationship between the significant increase of ∆R1 (reflecting contrast agent concentration) and disk degeneration. Iatridis et al. suggested that the dGEMRIC-technique (delayed Gadolinium Enhanced MRI of Cartilage), designed to indirectly quantify the fixed charge density by using an ionic contrast agent, could possibly be applied for the intervertebral disk [7] . The present results show considerable variation in the diffusion of contrast agent into the disks that may provide a competing mechanism for contrast agent intake and therefore may cause inaccuracy to the dGEMRIC measurement of the disk. The present results suggest that delayed enhancement of the interverbral disk may be used to study the nutritional pathway into the disk. The quantative method to measure disk enhancement may be a sensitive parameter to assess degeneration, and may provide a means to investigate the etiology of degenerative disk disease. 200 400 600 800 1000 before after T1 (ms) II (n=19) III (n=28) IV (n=42) V (n=4) 0.0 0.2 0.4 0.6 0.8 1.0 1.2 1.4 p<0.0001 p<0.001 ∆R1 (s -1 ) Pfirrmann grade REFERENCES 1. Boos N et al.
doi:10.1002/jmri.20693 pmid:16929532 fatcat:g2tmhoikv5holpu6ubk6bkkb5e

Infra-Slow EEG Fluctuations Are Correlated with Resting-State Network Dynamics in fMRI

T. Hiltunen, J. Kantola, A. Abou Elseoud, P. Lepola, K. Suominen, T. Starck, J. Nikkinen, J. Remes, O. Tervonen, S. Palva, V. Kiviniemi, J. M. Palva
2014 Journal of Neuroscience  
Ongoing neuronal activity in the CNS waxes and wanes continuously across widespread spatial and temporal scales. In the human brain, these spontaneous fluctuations are salient in blood oxygenation level-dependent (BOLD) signals and correlated within specific brain systems or "intrinsic-connectivity networks." In electrophysiological recordings, both the amplitude dynamics of fast (1-100 Hz) oscillations and the scalp potentials per se exhibit fluctuations in the same infra-slow (0.01-0.1 Hz)
more » ... quency range where the BOLD fluctuations are conspicuous. While several lines of evidence show that the BOLD fluctuations are correlated with fast-amplitude dynamics, it has remained unclear whether the infra-slow scalp potential fluctuations in full-band electroencephalography (fbEEG) are related to the resting-state BOLD signals. We used concurrent fbEEG and functional magnetic resonance imaging (fMRI) recordings to address the relationship of infra-slow fluctuations (ISFs) in scalp potentials and BOLD signals. We show here that independent components of fbEEG recordings are selectively correlated with subsets of cortical BOLD signals in specific task-positive and task-negative, fMRI-defined resting-state networks. This brain system-specific association indicates that infra-slow scalp potentials are directly associated with the endogenous fluctuations in neuronal activity levels. fbEEG thus yields a noninvasive, high-temporal resolution window into the dynamics of intrinsic connectivity networks. These results support the view that the slow potentials reflect changes in cortical excitability and shed light on neuronal substrates underlying both electrophysiological and behavioral ISFs.
doi:10.1523/jneurosci.0276-13.2014 pmid:24403137 pmcid:PMC6608153 fatcat:h4gdcucxmnedfmth4w3swxz76y

Diagnostic performance of semi-quantitative knee ultrasonography – Comparison with magnetic resonance imaging osteoarthritis knee score (MOAKS): Data from the Oulu osteoarthritis study

J. Podlipská, A. Guermazi, E. Liukkonen, E. Lammentausta, J. Niinimäki, M.T. Nieminen, O. Tervonen, J.M. Koski, S. Saarakkala
2015 Osteoarthritis and Cartilage  
Jackson z, O. Almagor y, F. Roemer x, A. Guermazi k, M. Crema k, M.C. Nevitt ¶, M. Hochberg #, K. Kwoh yy, C.B. Eaton zz, J. Bathon xx, J.S.  ... 
doi:10.1016/j.joca.2015.02.154 fatcat:zbc5pwpcfrby3f6uy5gvpuja6e

Spectral entropy indicates electrophysiological and hemodynamic changes in drug-resistant epilepsy – A multimodal MREG study

H. Helakari, J. Kananen, N. Huotari, L. Raitamaa, T. Tuovinen, V. Borchardt, A. Rasila, V. Raatikainen, T. Starck, T. Hautaniemi, T. Myllylä, O. Tervonen (+5 others)
2019 NeuroImage: Clinical  
Epilepsy causes measurable irregularity over a range of brain signal frequencies, as well as autonomic nervous system functions that modulate heart and respiratory rate variability. Imaging dynamic neuronal signals utilizing simultaneously acquired ultra-fast 10 Hz magnetic resonance encephalography (MREG), direct current electroencephalography (DC-EEG), and near-infrared spectroscopy (NIRS) can provide a more comprehensive picture of human brain function. Spectral entropy (SE) is a nonlinear
more » ... thod to summarize signal power irregularity over measured frequencies. SE was used as a joint measure to study whether spectral signal irregularity over a range of brain signal frequencies based on synchronous multimodal brain signals could provide new insights in the neural underpinnings of epileptiform activity.
doi:10.1016/j.nicl.2019.101763 pmid:30927607 pmcid:PMC6444290 fatcat:3xnz6n7fnvgqtc7mnis6t3jkde
« Previous Showing results 1 — 15 out of 553 results