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Alina Leminen Miika Leminen Teija Kujala Yury Shtyrov 《Cortex; a journal devoted to the study of the nervous system and behavior》2013
We investigated neural distinctions between inflectional and derivational morphology and their interaction with lexical frequency using the mismatch negativity (MMN), an established neurophysiological index of experience-dependent linguistic memory traces and automatic syntactic processing. We presented our electroencephalography (EEG) study participants with derived and inflected words of variable lexical frequencies against their monomorphemic base forms in a passive oddball paradigm, along with acoustically matched pseudowords. Sensor space and distributed source modelling results showed that at 100–150 msec after the suffix onset, derived words elicited larger responses than inflected words. Furthermore, real derived words showed advantage over pseudo-derivations and frequent derivations elicited larger activation than less frequent ones. This pattern of results is fully in line with previous research that explained lexical MMN enhancement by an activation of strongly connected word-specific long-term memory circuits, and thus suggests stronger lexicalisation for frequently used complex words. At the same time, a strikingly different pattern was found for inflectional forms: higher response amplitude for pseudo-inflections than for real inflected words, with no clear frequency effects. This is fully in line with previous MMN results on combinatorial processing of (morpho)syntactic stimuli: higher response to ungrammatical morpheme strings than grammatical ones, which does not depend on the string's surface frequency. This pattern suggests that, for inflectional forms, combinatorial processing route dominates over whole-form storage and access. In sum, our results suggest that derivations are more likely to form unitary representations than inflections which are likely to be processed combinatorially, and imply at least partially distinct brain mechanisms for the processing and representation of these two types of morphology. These dynamic mechanisms, underpinned by perisylvian networks, are activated rapidly, at 100–150 msec after the information arrives at the input, and in a largely automatic fashion, possibly providing neural basis for the first-pass morphological processing of spoken words. 相似文献
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Rheumatoid arthritis in identical twins: a clinical and immunogenetic study of eight concordant pairs derived from a nationwide twin panel 总被引:1,自引:0,他引:1
P J?rvinen M Koskenvuo S Koskimies K Kotaniemi K Aho 《Scandinavian journal of rheumatology》1991,20(3):159-164
The nationwide Finnish Twin Cohort was linked with the national Sickness Insurance Register. Eight identical twin pairs concordant for rheumatoid arthritis (RA) fulfilling the American Rheumatism Association criteria were identified. All 16 cases were known to be seropositive. Four pairs had at least one additional first-degree relative with RA, and the prevalence of RA among all the first-class relatives was 9%. HLA-typing was performed for 15 patients representing the eight pairs; six pairs carried the DR4 allele, and three of these pairs were putative homozygotes. Nodules and Sj?gren syndrome occurred fairly frequently (in 7 of 16 and 6 of 13 cases examined, respectively), but concordance within pairs was no higher than that expected by chance. The course of the disease was fulminant in one patient and in several others the disease had led to marked joint destructions. The findings pointed out to some intrapair similarity in the progression of the joint damage and in the type of complications caused by gold. 相似文献
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Juho-Antti Junno Markus Paananen Jaro Karppinen Tuija Tammelin Jaakko Niinimäki Eveliina Lammentausta Markku Niskanen Miika T. Nieminen Marjo-Riitta Järvelin Jani Takatalo Osmo Tervonen Juha Tuukkanen 《The spine journal》2013,13(2):184-189
Background contextReduced vertebral strength is a clear risk factor for vertebral fractures. Men and women with vertebral fractures often have reduced vertebral size and bone mineral density (BMD). Vertebral strength is controlled by both genetic and developmental factors. Malnutrition and low levels of physical activity are commonly considered to result in reduced bone size during growth. Several studies have also demonstrated the general relationship between BMD and physical activity in the appendicular skeleton.PurposeIn this study, we wanted to clarify the role of physical activity on vertebral bodies. Vertebral dimensions appear to generally be less pliant than long bones when lifetime changes occur. We wanted to explore the association between physical activity during late adolescence and vertebral strength parameters such as cross-sectional size and BMD.Study designThe association between physical activity and vertebral strength was explored by measuring vertebral strength parameters and defining the level of physical activity during adolescence.Patient sampleThe study population consisted of 6,928 males and females who, at 15 to 16 and 19 years of age, responded to a mailed questionnaire inquiring about their physical activity. A total of 558 individuals at the mean age of 21 years underwent magnetic resonance imaging (MRI) scans.MethodsWe measured the dimensions of the fourth lumbar vertebra from the MRI scans of the Northern Finland Birth Cohort 1986 and performed T2* relaxation time mapping, reflective of BMD. Vertebral strength was based on these two parameters. We analyzed the association of physical activity on vertebral strength using the analysis of variance.Results and conclusionsWe observed no association between the level of physical activity during late adolescence and vertebral strength at 21 years. 相似文献
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An evaluation of the challenges to developing tumor BRCA1 and BRCA2 testing methodologies for clinical practice
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Miika Ahdesmäki Sally Luke Paul M. Waring Andrew Wallace Ronnie Wright Benno Röthlisberger Katja Ludin Sabine Merkelbach‐Bruse Carina Heydt Marjolijn J.L. Ligtenberg Arjen R. Mensenkamp David Gonzalez de Castro Thomas Jones Ana Vivancos Olga Kondrashova Patrick Pauwels Christine Weyn Eric Hahnen Jan Hauke Richie Soong Zhongwu Lai Brian Dougherty T. Hedley Carr Justin Johnson John Mills J. Carl Barrett 《Human mutation》2018,39(3):394-405
Ovarian cancer patients with germline or somatic pathogenic variants benefit from treatment with poly ADP ribose polymerase (PARP) inhibitors. Tumor BRCA1/2 testing is more challenging than germline testing as the majority of samples are formalin‐fixed paraffin embedded (FFPE), the tumor genome is complex, and the allelic fraction of somatic variants can be low. We collaborated with 10 laboratories testing BRCA1/2 in tumors to compare different approaches to identify clinically important variants within FFPE tumor DNA samples. This was not a proficiency study but an inter‐laboratory comparison to identify common issues. Each laboratory received the same tumor DNA samples ranging in genotype, quantity, quality, and variant allele frequency (VAF). Each laboratory performed their preferred next‐generation sequencing method to report on the variants. No false positive results were reported in this small study and the majority of methods detected the low VAF variants. A number of variants were not detected due to the bioinformatics analysis, variant classification, or insufficient DNA. The use of hybridization capture or short amplicon methods are recommended based on a bioinformatic assessment of the data. The study highlights the importance of establishing standards and standardization for tBRCA testing particularly when the test results dictate clinical decisions regarding life extending therapies. 相似文献
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Vasara AI Nieminen MT Jurvelin JS Peterson L Lindahl A Kiviranta I 《Clinical orthopaedics and related research》2005,(433):233-242
Our main hypothesis was that indentation stiffness of the repair tissue approaches the values of adjacent cartilage 1 year after autologous chondrocyte transplantation. We also wanted to investigate the differences between osteochondritic lesions and full-thickness lesions. Thirty patients with cartilage lesions were operated on with autologous chondrocyte transplantation. The repair was evaluated arthroscopically, indentation stiffness was measured, and clinical evaluations were done. The stiffness of the repair tissue improved to 62% (mean 2.04 +/- 0.83 N, mean +/- SD) of adjacent cartilage (3.58 +/- 1.04 N). Fifty-three percent of the patients graded their knee as excellent or good and 47% of the patients graded their knee as fair at the followup. In six patients the normalized stiffness was at least 80%, suggesting hyaline-like repair. The indentation stiffness of the osteochondritis dissecans lesion repairs (1.45 +/- 0.46 N; n = 7) was less than that of the nonosteochondritis dissecans lesion repair sites (2.37 +/- 0.72 N; n = 19). Gadolinium-enhanced magnetic resonance imaging of the cartilage (dGEMRIC) during followup of four patients suggested proteoglycan replenishment, although all grafts showed low indentation values. Low stiffness values may indicate incomplete maturation or predominantly fibrous repair. The indentation analysis showed that the repair tissue stiffness could, in some cases, reach the same level as the adjacent cartilage, but there was a large variation among the grafts. 相似文献
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Chronic obstructive pulmonary disease (COPD) is one of the leading causes of morbidity and mortality worldwide. In Finland, the current prevalence of COPD is unknown. This population-based study aimed to assess the prevalence of COPD in Finland in adults 21-70 years of age by using internationally accepted criteria for COPD, and to evaluate risk factors for COPD. A random sample (n = 959) of questionnaire responders was invited to participate in a clinical study, which included a structured interview, skin-prick tests, and spirometry. Complete data were received from 683 subjects. According to the criteria of the British Thoracic Society and the Global Initiative for Chronic Obstructive Lung Disease, the prevalence of COPD was 5.4% and 9.4% respectively. The risk of COPD increased significantly with age, amount of smoking, and family history of obstructive airways disease, but not with skin-prick positive allergy, recreational skiing, or outdoor work. The smoking-adjusted risk of clinically relevant COPD did not differ significantly between men and women. Among subjects with a smoking history of more than 40 pack-years, the prevalence of COPD was over 50%. Early start age of smoking was a strong risk factor. 相似文献
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The known association between physical activity and low blood pressure may be influenced by inherited characteristics. Skeletal muscle consists of type I (slow-twitch) and type II (fast-twitch) muscle fibers, with proportions highly variable between individuals and mostly determined by genetic factors. A high percentage of type I fibers (type I%) has been associated with low blood pressure in cross-sectional studies. We investigated whether type I percentage predicts future blood pressure levels and explains part of the association between physical activity and blood pressure. At baseline, in 1984, muscle fiber-type distribution, physical activity, and body mass index (BMI) were determined in 64 healthy men (age, 32 to 58 years). At follow-up, in 2003, blood pressure, physical activity, and BMI were determined in these men. In subjects without antihypertensive medication (n=43), type I percentage accounted for 5%/18% of the variation in systolic/diastolic blood pressure. A high type I percentage predicted, independent of both baseline (in 1984) and follow-up (in 2003), physical activity, BMI, and low systolic and diastolic blood pressure. Adjusted for all baseline covariates, a 20-unit higher type I percentage predicted a 11.6-mm Hg lower systolic blood pressure (P=0.018) and a 5.0-mm Hg lower diastolic blood pressure (P=0.018). High levels of physical activity in 1984 predicted low diastolic blood pressure, but this association was lost when type I percentage was included into the model. A high proportion of type I fibers in skeletal muscle is an independent predictor of low blood pressure and explains part of the known association between high levels of physical activity and low blood pressure. 相似文献