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1.
Brain Behav Immun ; 115: 394-405, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37858740

RESUMO

BACKGROUND: Infection burden (IB), although linked to neurodegeneration, including Alzheimer's Disease (AD), has not been examined against neurite orientation, dispersion, and density imaging (NODDI) measures. METHODS: Among 38,803 UK Biobank adults (Age:40-70 years), we tested associations of total IB (IBtotal, 47.5 %) and hospital-treated IB (IBhosp, 9.7 %) with NODDI measures (5-15 years later), including volume fraction of Gaussian isotropic diffusion (ISOVF), intra-cellular volume fraction (ICVF) and orientation dispersion (OD) indices, using multiple linear regression models. RESULTS: Total and hospital-treated infection burdens (IBtotal and IBhosp) were associated with increased ISOVF, indicating increased free-water component. IBtotal was positively associated with OD, indicating that at higher IBtotal there was greater fanning of neurites. This was more evident in the lower cardiovascular health group. IBhosp was associated with higher OD, and lower ICVF at higher AD polygenic risk. Together, these findings indicate that both total and hospital-treated infections have effects on NODDI outcomes in the direction of poor brain health. These effects were largely homogeneous across cardiovascular health and AD polygenic risk groups, with some effects shown to be stronger at poor cardiovascular health and/or higher AD risk. CONCLUSIONS: Total and hospital-treated infections were associated with poorer white matter microstructure (higher ISOVF or OD or lower ICVF), with some heterogeneity across cardiovascular health and AD risk. Longitudinal studies with multiple repeats on neuroimaging markers in comparable samples are needed.


Assuntos
Imagem de Tensor de Difusão , Substância Branca , Imagem de Tensor de Difusão/métodos , Neuritos , Bancos de Espécimes Biológicos , Encéfalo , Substância Branca/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética/métodos
2.
Sensors (Basel) ; 21(18)2021 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-34577530

RESUMO

Clinical classification models are mostly pathology-dependent and, thus, are only able to detect pathologies they have been trained for. Research is needed regarding pathology-independent classifiers and their interpretation. Hence, our aim is to develop a pathology-independent classifier that provides prediction probabilities and explanations of the classification decisions. Spinal posture data of healthy subjects and various pathologies (back pain, spinal fusion, osteoarthritis), as well as synthetic data, were used for modeling. A one-class support vector machine was used as a pathology-independent classifier. The outputs were transformed into a probability distribution according to Platt's method. Interpretation was performed using the explainable artificial intelligence tool Local Interpretable Model-Agnostic Explanations. The results were compared with those obtained by commonly used binary classification approaches. The best classification results were obtained for subjects with a spinal fusion. Subjects with back pain were especially challenging to distinguish from the healthy reference group. The proposed method proved useful for the interpretation of the predictions. No clear inferiority of the proposed approach compared to commonly used binary classifiers was demonstrated. The application of dynamic spinal data seems important for future works. The proposed approach could be useful to provide an objective orientation and to individually adapt and monitor therapy measures pre- and post-operatively.


Assuntos
Inteligência Artificial , Aprendizado de Máquina , Humanos , Postura , Máquina de Vetores de Suporte
3.
Cereb Cortex ; 26(7): 2970-81, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26045569

RESUMO

Cyclic AMP response element-binding protein (CREB) contributes to adaptation of mesocorticolimbic networks by modulating activity-regulated transcription and plasticity in neurons. Activity or expression changes of CREB in the nucleus accumbens (NAc) and orbital frontal cortex (OFC) interact with behavioral changes during reward-motivated learning. However, these findings from animal models have not been evaluated in humans. We tested whether CREB1 genotypes affect reward-motivated decisions and related brain activation, using BOLD fMRI in 224 young and healthy participants. More specifically, participants needed to adapt their decision to either pursue or resist immediate rewards to optimize the reward outcome. We found significant CREB1 genotype effects on choices to pursue increases of the reward outcome and on BOLD signal in the NAc, OFC, insula cortex, cingulate gyrus, hippocampus, amygdala, and precuneus during these decisions in comparison with those decisions avoiding total reward loss. Our results suggest that CREB1 genotype effects in these regions could contribute to individual differences in reward- and associative memory-based decision-making.


Assuntos
Adaptação Psicológica/fisiologia , Encéfalo/fisiologia , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Tomada de Decisões/fisiologia , Recompensa , Adulto , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Circulação Cerebrovascular/fisiologia , Função Executiva/fisiologia , Feminino , Genótipo , Técnicas de Genotipagem , Humanos , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Oxigênio/sangue , Polimorfismo de Nucleotídeo Único , Adulto Jovem
4.
Eur Arch Psychiatry Clin Neurosci ; 264(2): 93-102, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23880959

RESUMO

Affective deficits are one common denominator of schizophrenia (SZ), bipolar disorder (BD) and obsessive compulsive disorder (OCD) with the amygdala indicated as one of the major structures involved in emotion regulation. Previous findings of differences in amygdala volume between healthy controls and patients with SZ, BD or OCD diverge with respect to the affected hemisphere, size and direction of the effect. Variability in the CACNA1C gene has been linked to BD, SZ as well as structural and functional variation in the amygdala in healthy people and patients with BD. We were interested to investigate whether amygdala volumes differ between hemispheres, diagnostic or genotype groups, and whether any interactive effects exist. We combined genotyping of SNP rs1006737 in CACNA1C with structural MRI measurements of relative gray matter (GM) amygdala volume in patients with SZ, BD or OCD as well as healthy controls (N Total = 72). The CACNA1C genotype showed a significant effect on relative GM amygdala volume in patients with SZ. There was a significant left versus right relative GM amygdala volume decrease in patients with SZ or BD. The effects of hemisphere and diagnosis (controls vs. patients with SZ) on relative GM amygdala volume were genotype specific. Our data suggest that the CACNA1C genotype may account for some heterogeneity in the effects of hemisphere and diagnosis on amygdala volume when comparing patients with SZ and controls and point to disturbed Ca(2+)-signaling as a plausible mechanism contributing to the pathology in patients with SZ.


Assuntos
Tonsila do Cerebelo/patologia , Canais de Cálcio/genética , Individualidade , Transtornos do Humor/complicações , Polimorfismo de Nucleotídeo Único/genética , Esquizofrenia , Adulto , Análise de Variância , Feminino , Lateralidade Funcional , Genótipo , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Esquizofrenia/complicações , Esquizofrenia/genética , Esquizofrenia/patologia , Estatística como Assunto , Adulto Jovem
5.
Front Bioeng Biotechnol ; 12: 1350135, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38419724

RESUMO

Objective: Biomechanical Machine Learning (ML) models, particularly deep-learning models, demonstrate the best performance when trained using extensive datasets. However, biomechanical data are frequently limited due to diverse challenges. Effective methods for augmenting data in developing ML models, specifically in the human posture domain, are scarce. Therefore, this study explored the feasibility of leveraging generative artificial intelligence (AI) to produce realistic synthetic posture data by utilizing three-dimensional posture data. Methods: Data were collected from 338 subjects through surface topography. A Variational Autoencoder (VAE) architecture was employed to generate and evaluate synthetic posture data, examining its distinguishability from real data by domain experts, ML classifiers, and Statistical Parametric Mapping (SPM). The benefits of incorporating augmented posture data into the learning process were exemplified by a deep autoencoder (AE) for automated feature representation. Results: Our findings highlight the challenge of differentiating synthetic data from real data for both experts and ML classifiers, underscoring the quality of synthetic data. This observation was also confirmed by SPM. By integrating synthetic data into AE training, the reconstruction error can be reduced compared to using only real data samples. Moreover, this study demonstrates the potential for reduced latent dimensions, while maintaining a reconstruction accuracy comparable to AEs trained exclusively on real data samples. Conclusion: This study emphasizes the prospects of harnessing generative AI to enhance ML tasks in the biomechanics domain.

6.
Neuropsychobiology ; 67(2): 84-92, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23295962

RESUMO

BACKGROUND: Genetic susceptibility to schizophrenia (SZ) has been suggested to influence the cortical systems supporting working memory (WM) and face processing. Genetic imaging studies link the SZ risk variant rs1344706 on the ZNF804A gene to psychosis via alterations in functional brain connectivity during WM, but no work has looked at the effects of ZNF804A on WM with face-processing components. METHODS: We therefore investigated healthy controls that were genotyped for rs1344706 with a face WM task during functional magnetic resonance imaging. We suggested that variation at the rs1344706 locus would be associated with similar alterations as patients previously tested using the same WM task for faces. RESULTS: The rs1344706 risk allele was indeed associated with altered activation in the right dorsolateral prefrontal (rDLPFC) cortex. We established that the rDLPFC was activated in a task-dependent manner, suggesting that the differences in activation between rs1344706 genotype groups reflected alterations in task processing. Furthermore, we demonstrated that the rDLPFC region showed significant volumetric overlap with the rDLPFC which had previously been reported to be altered during task processing for patients with SZ. CONCLUSIONS: The findings support an association between rs1344706 and alterations in DLPFC activity during WM for faces. We further suggest that WM for faces may be a useful intermediate phenotype in the investigation of genetic susceptibility to psychosis.


Assuntos
Mapeamento Encefálico , Face , Fatores de Transcrição Kruppel-Like/genética , Memória de Curto Prazo/fisiologia , Polimorfismo de Nucleotídeo Único/genética , Córtex Pré-Frontal/fisiologia , Adulto , Análise de Variância , Emoções/fisiologia , Feminino , Lateralidade Funcional , Genótipo , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Oxigênio/sangue , Reconhecimento Visual de Modelos , Estimulação Luminosa , Córtex Pré-Frontal/irrigação sanguínea , Reconhecimento Psicológico/fisiologia , Adulto Jovem
7.
Data Brief ; 48: 109178, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37383806

RESUMO

Spinal function is substantially related to the motion of the particular vertebrae and the spine as a whole. For systematic assessment of individual motion, data sets are required which cover the kinematics comprehensively. Additionally, the data should enable a comparison of inter- and intraindividual variation of vertebral orientation in dedicated motion tasks like gait. For this purpose, this article provides surface topography (ST) data which were acquired while the individual test persons were walking on a treadmill at three different speed levels (2 km/h, 3 km/h, 4 km/h). In each recording, ten full walking cycles were included per test case to enable a detailed analysis of motion patterns. The provided data reflects asymptomatic and pain-free volunteers. Each data set contains the vertebral orientation in all three motion directions for the vertebra prominens down to L4 as well as the pelvis. Additionally, spinal parameters like balance, slope, and lordosis / kyphosis parameters as well as an assignment of the motion data to single gait cycles are included. The complete raw data set without any preprocessing is provided. This allows to apply a broad range of further signal processing and evaluation steps in order to identify characteristic motion patterns as well as intra- and inter-individual variation of vertebral motion.

8.
Hum Mov Sci ; 88: 103054, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36621141

RESUMO

Spinal dynamics during gait have been of interest in research for many decades. Based on respective previous investigations, the pelvis is generally expected to be maximally forward rotated on the side of the reference leg at the beginning of each gait cycle and to reach its maximum counterrotation approximately at the end of the reference leg's stance phase. The pelvic-upper-thoracic-spine coordination converges towards an anti-phase movement pattern in high velocities during ambulation. The vertebral bodies around the seventh thoracic vertebra are considered to be an area of transition during human ambulation where no or at least little rotary motion can be observed. The respective cranial and caudal vertebrae meanwhile are expected to rotate conversely around this spinal point of intersection. However, these previous assumptions are based on scarce existing research, whereby only isolated vertebrae have been analyzed contemporaneously. Due to huge methodological differences in data capturing approaches, the results are additionally hardly comparable to each other and involved measurement procedures are often not implementable in clinical routines. Furthermore, none of the above-mentioned methods provided reference data for spinal motion during gait based on an appropriate number of healthy participants. Hence, the aim of this study was to present such reference data for spinal rotary motion of every vertebral body from C7 down to L4 and the pelvis derived from surface topographic back shape analyses in a cohort of 201 healthy participants walking on a treadmill at a given walking speed of 5 km/h. Additionally, the spine's functional movement behavior during gait should be described in the transverse plane based on data derived from this noninvasive, clinically suitable measurement approach and, in conclusion, the results shall be compared against those of previous research findings derived from other measurement techniques. Contrary to the previous functional understanding, the area of the mid-thoracic spine was found to demonstrate the largest amplitude of rotary motion of all investigated vertebrae and revealed an approximately counterrotated movement behavior compared to the rotary motion of the pelvis. In both directions, spinal rotation during gait seemed to be initiated by the pelvis. The overlying vertebrae followed in succession in the sense of an ongoing movement. Therefore, the point of intersection was not statically located in a specific anatomical section of the spine. Instead, it was found to be dynamic, ascending from one vertebra to the next from caudal to cranial in dependence of the pelvis's rotation initiation.


Assuntos
Marcha , Caminhada , Humanos , Valores de Referência , Vértebras Torácicas , Pelve , Rotação , Fenômenos Biomecânicos
9.
Hum Mov Sci ; 87: 103036, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36395570

RESUMO

Vertebral motion reveals complex patterns, which are not yet understood in detail. This applies to vertebral kinematics in general but also to specific motion tasks like gait. For gait analysis, most of existing publications focus on averaging characteristics of recorded motion signals. Instead, this paper aims at analyzing intra- and inter-individual variation specifically and elaborating motion parameters, which are consistent during gait cycles of particular persons. For this purpose, a study design was utilized, which collected motion data from 11 asymptomatic test persons walking at different speed levels (2, 3, and 4 km/h). Acquisition of data was performed using surface topography. The motion signals were preprocessed in order to separate average vertebral orientations (neutral profiles) from basic gait cycles. Subsequently, a k-means clustering technique was applied to figure out, whether a discrimination of test persons was possible based on the preprocessed motion signals. The paper shows that each test sequence could be assigned to the particular test person without additional prior information. In particular, the neutral profiles appeared to be highly consistent intra-individually (across the gait cycles as well as speed levels), but substantially different between test persons. A full discrimination of test persons was achieved using the neutral profiles with respect to flexion/extension data. Based on this, these signals can be considered as individual characteristics for the particular test persons.


Assuntos
Marcha , Coluna Vertebral , Humanos , Caminhada , Movimento (Física) , Análise da Marcha , Fenômenos Biomecânicos , Amplitude de Movimento Articular
10.
Life (Basel) ; 13(6)2023 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-37374174

RESUMO

The rise in the occurrence of musculoskeletal disorders, such as thoracic hyperkyphosis (THK) or lumbar hypolordosis (LHL), is a result of demographic changes. Exercise therapy is an effective approach that can reduce related disabilities and costs. To ensure successful therapy, an individualized exercise program adapted to the severity of the disorder is expedient. Nevertheless, appropriate classification systems are scarce. This project aimed to develop and evaluate a severity classification focused on exercise therapy for patients with THK or LHL. A multilevel severity classification was developed and evaluated by means of an online survey. Reference limits of spinal shape angles were established by data from video rasterstereography of 201 healthy participants. A mean kyphosis angle of 50.03° and an average lordosis angle of 40.72° were calculated as healthy references. The strength of the multilevel classification consisting of the combination of subjective pain and objective spinal shape factors was confirmed by the survey (70% agreement). In particular, the included pain parameters were considered relevant by 78% of the experts. Even though the results of the survey provide important evidence for further analyses and optimization options of the classification system, the current version is still acceptable as therapeutic support.

11.
Bioengineering (Basel) ; 10(9)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37760188

RESUMO

Adolescent idiopathic scoliosis (AIS) is a three-dimensional axial deviation of the spine diagnosed in adolescence. Despite a long daily sitting duration, there are no studies on whether scoliosis can be positively influenced by sitting on a seat wedge. For the prospective study, 99 patients with AIS were measured with the DIERS formetric III 4D average, in a standing position, on a level seat and with three differently inclined seat wedges (3°, 6° and 9°). The rasterstereographic parameters 'scoliosis angle' and 'lateral deviation RMS' were analysed. The side (ipsilateral/contralateral) on which the optimal correcting wedge was located in relation to the lumbar/thoraco-lumbar convexity was investigated. It was found that the greatest possible correction of scoliosis occurred with a clustering in wedges with an elevation on the ipsilateral side of the convexity. This clustering was significantly different from a uniform distribution (p < 0.001; chi-square = 35.697 (scoliosis angle); chi-square = 54.727 (lateral deviation RMS)). It should be taken into account that the effect of lateral seat wedges differs for individual types of scoliosis and degrees of severity. The possibility of having a positive effect on scoliosis while sitting holds great potential, which is worth investigating in follow-up studies.

12.
Clin Chem ; 58(2): 441-9, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22205695

RESUMO

BACKGROUND: Growth differentiation factor-15 (GDF-15) is a stress-responsive marker that might aid in the early diagnosis and risk stratification of patients with suspected acute myocardial infarction (AMI). METHODS: In a prospective, international multicenter study, GDF-15, high-sensitivity cardiac troponin T (hs-cTnT), and B-type natriuretic peptide (BNP) were measured in 646 unselected patients presenting to the emergency department with acute chest pain. The final diagnosis was adjudicated by 2 independent cardiologists. The primary prognostic end point was all-cause mortality during a median follow-up of 26 months. RESULTS: AMI was the adjudicated final diagnosis in 115 patients (18%). GDF-15 concentrations at presentation were significantly higher in AMI patients compared to patients with other diagnoses. The diagnostic accuracy of GDF-15 at presentation for the diagnosis of AMI as quantified by the area under the ROC curve (AUC) was lower (AUC 0.69, 95% CI 0.64-0.74) compared to hs-cTnT (AUC 0.96, 95% CI 0.94-0.98, P < 0.001) and BNP (AUC 0.74, 95% CI 0.69-0.80, P = 0.02). A total of 55 deaths occurred during follow-up. GDF-15 predicted all-cause mortality independently of and more accurately than hs-cTnT [AUC 0.85 (95% CI 0.81-0.90) vs 0.77 (95% CI 0.72-0.83), P = 0.002] and BNP (AUC 0.75, 95% CI 0.68-0.82, P = 0.007). Net reclassification improvement was 0.15 (P = 0.01), and the absolute integrated discrimination improvement was 0.07, yielding a relative integrated discrimination improvement of 0.36 (P = 0.07). CONCLUSIONS: GDF-15 predicts all-cause mortality in unselected patients with acute chest pain independently of and more accurately than hs-cTnT and BNP. However, GDF-15 does not seem to help in the early diagnosis of AMI.


Assuntos
Dor no Peito/diagnóstico , Fator 15 de Diferenciação de Crescimento/sangue , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Angina Instável/diagnóstico , Biomarcadores/sangue , Dor no Peito/mortalidade , Diagnóstico Precoce , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mortalidade , Infarto do Miocárdio/diagnóstico , Peptídeo Natriurético Encefálico/sangue , Prognóstico , Estudos Prospectivos , Medição de Risco , Troponina T/sangue
13.
Nucleic Acids Res ; 38(9): e106, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20139417

RESUMO

Recombinase-mediated cassette exchange (RMCE) exploits the possibility to unidirectionally exchange any genetic material flanked by heterotypic recombinase recognition sites (RRS) with target sites in the genome. Due to a limited number of available pre-fabricated target sites, RMCE in mouse embryonic stem (ES) cells has not been tapped to its full potential to date. Here, we introduce a universal system, which allows the targeted insertion of any given transcriptional unit into 85 742 previously annotated retroviral conditional gene trap insertions, representing 7013 independent genes in mouse ES cells, by RMCE. This system can be used to express any given cDNA under the control of endogenous trapped promoters in vivo, as well as for the generation of transposon 'launch pads' for chromosomal region-specific 'Sleeping Beauty' insertional mutagenesis. Moreover, transcription of the gene-of-interest is only activated upon Cre-recombinase activity, a feature that adds conditionality to this expression system, which is demonstrated in vivo. The use of the RMCE system presented in this work requires one single-cloning step followed by one overnight gateway clonase reaction and subsequent cassette exchange in ES cells with efficiencies of 40% in average.


Assuntos
DNA Complementar/biossíntese , Marcação de Genes/métodos , Recombinases/metabolismo , Animais , Cinamatos/farmacologia , DNA Nucleotidiltransferases/metabolismo , Marcadores Genéticos , Vetores Genéticos , Higromicina B/análogos & derivados , Higromicina B/farmacologia , Integrases/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Mutagênese Insercional , Regiões Promotoras Genéticas , Recombinação Genética , Transposases/metabolismo
14.
Hum Mov Sci ; 81: 102919, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34979480

RESUMO

Analysis of spinal motion is considered to be important to assess function of the human spine. Surface topography (ST) is a method to record the vertebral orientation in 3D. Such measurements can be performed in static but also in dynamic situations like gait or other motion tasks. However, dynamic ST measurements are hard to interpret due to their complexity. The main goal of this paper is to provide comprehensive visualization tools which allow a more intuitive and comprehensive interpretation n of such measurements. In particular, juxtaposition and superimposition techniques are utilized to emphasize differences in motion characteristics. The method was applied to a test series of 12 healthy volunteers walking on a treadmill at various speed levels. It could be shown that the visualization tools are helpful to compare different motion sequences including an analysis of intra- and interindividual variation. Based on these techniques, it could be shown that the profiles of vertebral orientation remain considerable constant when one person was walking at different speed levels whereas they differed substantially between the different individuals. In contrast, the motion amplitudes contained high intra- and interindividual variation, i.e. between speed levels and different test persons. In summary, the paper demonstrates that appropriate visualization tools are helpful to interpret ST measurements and cope with the complexity of these data sets. In particular, they can be used to compare different motion sequences in a more comprehensive way.


Assuntos
Marcha , Coluna Vertebral , Fenômenos Biomecânicos , Teste de Esforço , Humanos , Movimento (Física) , Caminhada
15.
Bioengineering (Basel) ; 9(12)2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36551015

RESUMO

Visual examinations are commonly used to analyze spinal posture. Even though they are simple and fast, their interrater reliability is poor. Suitable alternatives should be objective, non-invasive, valid and reliable. Videorasterstereography (VRS) is a corresponding method that is increasingly becoming established. However, there is a lack of reference data based on adequate numbers of participants and structured subgroup analyses according to sex and age. We used VRS to capture the spinal posture of 201 healthy participants (aged 18-70 years) divided into three age cohorts. Three-dimensional reference data are presented for the global spine parameters and for every vertebral body individually (C7-L4) (here called the specific spine parameters). The vertebral column was found to be systematically asymmetric in the transverse and the coronal planes. Graphical presentations of the vertebral body posture revealed systematic differences between the subgroups; however, large standard deviations meant that these differences were not significant. In contrast, several global parameters (e.g., thoracic kyphosis and lumbar lordosis) indicated differences between the analyzed subgroups. The findings confirm the importance of presenting reference data not only according to sex but also according to age in order to map physiological posture changes over the life span. The question also arises as to whether therapeutic approximations to an almost symmetrical spine are biomechanically desirable.

16.
Comput Methods Biomech Biomed Engin ; 25(7): 821-831, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34587827

RESUMO

Surface topography systems enable the capture of spinal dynamic movement; however, it is unclear whether vertebral dynamics are unique enough to identify individuals. Therefore, in this study, we investigated whether the identification of individuals is possible based on dynamic spinal data. Three different data representations were compared (automated extracted features using contrastive loss and triplet loss functions, as well as simple descriptive statistics). High accuracies indicated the possible existence of a personal spinal 'fingerprint', therefore enabling subject recognition. The present work forms the basis for an objective comparison of subjects and the transfer of the method to clinical use cases.


Assuntos
Aprendizado de Máquina , Redes Neurais de Computação , Humanos , Movimento (Física) , Movimento , Coluna Vertebral/diagnóstico por imagem
17.
Neuropsychobiology ; 64(2): 93-101, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21701227

RESUMO

BACKGROUND: Dysfunctional working memory (WM) has been recognized as one of the most consistent deficits in schizophrenia. Studies that investigated the neural correlates of WM-related pathology by comparing patients with schizophrenia and control participants have produced controversial results, reporting task-related hyper- or hypoactivity in frontoparietal networks. METHOD: We addressed this question by comparing BOLD signals for accurate responses during a WM task for emotional faces between a homogeneous group of high-performing patients and a control group. RESULTS: Our results confirm previous findings of left prefrontal hyperactivity contrasted with hypoactivity in right prefrontal cortex to support WM performance. We also extend previous work by reporting enhanced activity in higher visual areas of patients during encoding and maintenance. CONCLUSION: Our findings and those of the literature can be integrated into a model, where preserved visual cognition in high-functioning patients with hypofrontality is explained by activation of contralateral homologue areas combined with enhanced recruitment of sensory areas.


Assuntos
Encéfalo/irrigação sanguínea , Transtornos da Memória/etiologia , Transtornos da Memória/patologia , Memória de Curto Prazo/fisiologia , Esquizofrenia Paranoide/complicações , Adulto , Análise de Variância , Mapeamento Encefálico , Emoções , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Oxigênio/sangue , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa , Tempo de Reação , Adulto Jovem
18.
J Periodontol ; 92(8): 1163-1170, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33155276

RESUMO

BACKGROUND: This practice-based retrospective study evaluated a screening method for diabetes mellitus (DM) in patients with Stage III or IV periodontitis using the FINDRISC questionnaire. METHODS: Patients with Stage III or IV periodontitis who received FINDRISC screening in a German private dental practice were recruited. Individuals with positive FINDRISC scores (≥12, FINDRISC+) were referred for diabetological examination. Several general and periodontal findings from the patients' documentation were recorded and analyzed. RESULTS: A total of 179 patients (52.65 ± 11.49 years) were included. In DM screening, 24.6% (n = 44) patients were FINDRISC+, including all patients with currently known DM (21 of 21). Of the remaining FINDRISC+ patients, 82.6% (19 of 23) visited their general practitioner, and 63.2% (12 of 19, 7.6% of total cohort) had an HbA1c ≥5.7%. Accordingly, 75% of the FINDRISC+ patients were diabetologically conspicuous (HbA1c ≥ 5.7%), including those with already known DM. Patients with previously unknown DM showed higher mean age, more missing teeth, a higher periodontitis stage (more Stage IV) and more frequently teeth with suppuration compared with the diabetologically inconspicuous individuals (P <0.01). CONCLUSION: The FINDRISC questionnaire is appropriate for patients with Stage III or IV periodontitis and can be recommended in dental practice setting.


Assuntos
Diabetes Mellitus Tipo 2 , Periodontite , Diabetes Mellitus Tipo 2/diagnóstico , Humanos , Programas de Rastreamento , Periodontite/diagnóstico , Periodontite/epidemiologia , Estudos Retrospectivos , Inquéritos e Questionários
19.
Comput Methods Biomech Biomed Engin ; 24(3): 299-307, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33135504

RESUMO

Modern technologies enable to capture multiple biomechanical parameters often resulting in relational data. The current work proposes a generally applicable method comprising automated feature extraction, ensemble feature selection and classification to best capture the potentials of the data also for generating new biomechanical knowledge. Its benefits are demonstrated in the concrete biomechanically and medically relevant use case of gender classification based on spinal data for stance and gait. Very good results for accuracy were obtained using gait data. Dynamic movements of the lumbar spine in sagittal and frontal plane and of the pelvis in frontal plane best map gender differences.


Assuntos
Algoritmos , Marcha/fisiologia , Descoberta do Conhecimento , Postura/fisiologia , Caracteres Sexuais , Automação , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
20.
J Orthop Surg Res ; 16(1): 703, 2021 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-34863230

RESUMO

BACKGROUND: Deviations from a conventional physiologic posture are often a cause of complaint. According to current literature, the upright physiological spine posture exhibits inclinations in the sagittal plane but not in the coronal and transverse planes, but individual vertebral body positions of asymptomatic adults have rarely been described using surface topography. Therefore, this work aims to form a normative reference dataset for the thoracic and lumbar vertebral bodies and for the pelvis in all three planes in asymptomatic women. METHODS: In a prospective, cross-sectional, monocentric study, 100 pain-free asymptomatic women, aged 20-64 years were enrolled. Habitual standing positions of the trunk were measured using surface topography. Data were analyzed in all three planes. Age sub-analysis was: 1) ages ≤ 40 years and 2) ages ≥ 41 years. Two-sample t-tests were used for age comparisons of the vertebral bodies, vertebra prominence (VP)-L4, and global parameters. One-sample t-tests were used to test deviations from symmetrical zero positions of VP-L4. RESULTS: Coronal plane: on average, the vertebral bodies were tilted to the right between the VP and T4 (maximum: T2 - 1.8° ± 3.2), while between T6 and T11 they were tilted to the left (maximum: T7 1.1° ± 1.9). T5 and L2 were in a neutral position, overall depicting a mean right-sided lateral flexion from T2 to T7 (apex at T5). Sagittal plane: the kyphotic apex resided at T8 with - 0.5° ± 3.6 and the lumbar lordotic apex at L3 with - 2.1° ± 7.4. Transverse plane: participants had a mean vertebral body rotation to the right ranging from T6 to L4 (maximum: T11 - 2.2° ± 3.5). Age-specific differences were seen in the sagittal plane and had little effect on overall posture. CONCLUSIONS: Asymptomatic female volunteers standing in a habitual posture displayed an average vertebral rotation and lateral flexion to the right in vertebral segments T2-T7. The physiological asymmetrical posture of women could be considered in spinal therapies. With regard to spinal surgery, it should be clarified whether an approximation to an absolutely symmetrical posture is desirable from a biomechanical point of view? This data set can also be used as a reference in clinical practice. TRIAL REGISTRATION: This study was registered with WHO (INT: DRKS00010834) and approved by the responsible ethics committee at the Rhineland-Palatinate Medical Association (837.194.16).


Assuntos
Pelve , Adulto , Estudos Transversais , Feminino , Humanos , Vértebras Lombares/diagnóstico por imagem , Pelve/diagnóstico por imagem , Estudos Prospectivos , Amplitude de Movimento Articular
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