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1.
Artigo em Inglês | MEDLINE | ID: mdl-38951363

RESUMO

PURPOSE: Micro-electrode recordings (MERs) are a key intra-operative modality used during deep brain stimulation (DBS) electrode implantation, which allow for a trained neurophysiologist to infer the anatomy in which the electrode is placed. As DBS targets are small, such inference is necessary to confirm that the electrode is correctly positioned. Recently, machine learning techniques have been used to augment the neurophysiologist's capability. The goal of this paper is to investigate the generalisability of these methods with respect to different clinical centres and training paradigms. METHODS: Five deep learning algorithms for binary classification of MER signals have been implemented. Three databases from two different clinical centres have also been collected with differing size, acquisition hardware, and annotation protocol. Each algorithm has initially been trained on the largest database, then either directly tested or fine-tuned on the smaller databases in order to estimate their generalisability. As a reference, they have also been trained from scratch on the smaller databases as well in order to estimate the effect of the differing database sizes and annotation systems. RESULTS: Each network shows significantly reduced performance (on the order of a 6.5% to 16.0% reduction in balanced accuracy) when applied out-of-distribution. This reduction can be ameliorated through fine-tuning the network on the new database through transfer learning. Although, even for these small databases, it appears that retraining from scratch may still offer equivalent performance as fine-tuning with transfer learning. However, this is at the expense of significantly longer training times. CONCLUSION: Generalisability is an important criterion for the success of machine learning algorithms in clinic. We have demonstrated that a variety of recent machine learning algorithms for MER classification are negatively affected by domain shift, but that this can be quickly ameliorated through simple transfer learning procedures that can be readily performed for new centres.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38874653

RESUMO

PURPOSE: Frontotemporal lobe dementia (FTD) results from the degeneration of the frontal and temporal lobes. It can manifest in several different ways, leading to the definition of variants characterised by their distinctive symptomatologies. As these variants are detected based on their symptoms, it can be unclear if they represent different types of FTD or different symptomatological axes. The goal of this paper is to investigate this question with a constrained cohort of FTD patients in order to see if the heterogeneity within this cohort can be inferred from medical images rather than symptom severity measurements. METHODS: An ensemble of convolutional neural networks (CNNs) is used to classify diffusion tensor images collected from two databases consisting of 72 patients with behavioural variant FTD and 120 healthy controls. FTD biomarkers were found using voxel-based analysis on the sensitivities of these CNNs. Sparse principal components analysis (sPCA) is then applied on the sensitivities arising from the patient cohort in order to identify the axes along which the patients express these biomarkers. Finally, this is correlated with their symptom severity measurements in order to interpret the clinical presentation of each axis. RESULTS: The CNNs result in sensitivities and specificities between 83 and 92%. As expected, our analysis determines that all the robust biomarkers arise from the frontal and temporal lobes. sPCA identified four axes in terms of biomarker expression which are correlated with symptom severity measurements. CONCLUSION: Our analysis confirms that behavioural variant FTD is not a singular type or spectrum of FTD, but rather that it has multiple symptomatological axes that relate to distinct regions of the frontal and temporal lobes. This analysis suggests that medical images can be used to understand the heterogeneity of FTD patients and the underlying anatomical changes that lead to their different clinical presentations.

3.
HIV Med ; 25(2): 212-222, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37775947

RESUMO

OBJECTIVES: The main objective of this analysis was to evaluate the impact of pre-existing drug resistance by next-generation sequencing (NGS) on the risk of treatment failure (TF) of first-line regimens in participants enrolled in the START study. METHODS: Stored plasma from participants with entry HIV RNA >1000 copies/mL were analysed using NGS (llumina MiSeq). Pre-existing drug resistance was defined using the mutations considered by the Stanford HIV Drug Resistance Database (HIVDB v8.6) to calculate the genotypic susceptibility score (GSS, estimating the number of active drugs) for the first-line regimen at the detection threshold windows of >20%, >5%, and >2% of the viral population. Survival analysis was conducted to evaluate the association between the GSS and risk of TF (viral load >200 copies/mL plus treatment change). RESULTS: Baseline NGS data were available for 1380 antiretroviral therapy (ART)-naïve participants enrolled over 2009-2013. First-line ART included a non-nucleoside reverse transcriptase inhibitor (NNRTI) in 976 (71%), a boosted protease inhibitor in 297 (22%), or an integrase strand transfer inhibitor in 107 (8%). The proportions of participants with GSS <3 were 7% for >20%, 10% for >5%, and 17% for the >2% thresholds, respectively. The adjusted hazard ratio of TF associated with a GSS of 0-2.75 versus 3 in the subset of participants with mutations detected at the >2% threshold was 1.66 (95% confidence interval 1.01-2.74; p = 0.05) and 2.32 (95% confidence interval 1.32-4.09; p = 0.003) after restricting the analysis to participants who started an NNRTI-based regimen. CONCLUSIONS: Up to 17% of participants initiated ART with a GSS <3 on the basis of NGS data. Minority variants were predictive of TF, especially for participants starting NNRTI-based regimens.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Soropositividade para HIV , HIV-1 , Humanos , Infecções por HIV/epidemiologia , HIV-1/genética , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Inibidores da Transcriptase Reversa/uso terapêutico , Soropositividade para HIV/tratamento farmacológico , Sequenciamento de Nucleotídeos em Larga Escala , Carga Viral , Farmacorresistência Viral/genética
4.
Int J Comput Assist Radiol Surg ; 19(2): 283-296, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37815676

RESUMO

PURPOSE: Point localisation is a critical aspect of many interventional planning procedures, specifically representing anatomical regions of interest or landmarks as individual points. This could be seen as analogous to the problem of visual search in cognitive psychology, in which this search is performed either: bottom-up, constructing increasingly abstract and coarse-resolution features over the entire image; or top-down, using contextual cues from the entire image to refine the scope of the region being investigated. Traditional convolutional neural networks use the former, but it is not clear if this is optimal. This article is a preliminary investigation as to how this motivation affects 3D point localisation in neuro-interventional planning. METHODS: Two neuro-imaging datasets were collected: one for cortical point localisation for repetitive transcranial magnetic stimulation and the other for sub-cortical anatomy localisation for deep brain stimulation. Four different frameworks were developed using top-down versus bottom-up paradigms as well as representing points as co-ordinates or heatmaps. These networks were applied to point localisation for transcranial magnetic stimulation and subcortical anatomy localisation. These networks were evaluated using cross-validation and a varying number of training datasets to analyse their sensitivity to quantity of training data. RESULTS: Each network shows increasing performance as the amount of available training data increases, with the co-ordinate-based top-down network consistently outperforming the others. Specifically, the top-down architectures tend to outperform the bottom-up ones. An analysis of their memory consumption also encourages the top-down co-ordinate based architecture as it requires significantly less memory than either bottom-up architectures or those representing their predictions via heatmaps. CONCLUSION: This paper is a preliminary foray into a fundamental aspect of machine learning architectural design: that of the top-down/bottom-up divide from cognitive psychology. Although there are additional considerations within the particular architectures investigated that could affect these results and the number of architectures investigated is limited, our results do indicate that the less commonly used top-down paradigm could lead to more efficient and effective architectures in the future.


Assuntos
Aprendizado Profundo , Humanos , Imageamento por Ressonância Magnética , Redes Neurais de Computação , Aprendizado de Máquina
5.
Artigo em Inglês | MEDLINE | ID: mdl-37406465

RESUMO

INTRODUCTION: Environmental factors in the operating room during cesarean sections are likely important for both women/birthing people and their babies but there is currently a lack of rigorous literature about their evaluation. The principal aim of this study was to systematically examine studies published on the physical environment in the obstetrical operating room during c-sections and its impact on mother and neonate outcomes. The secondary objective was to identify the sensors used to investigate the operating room environment during cesarean sections. METHODS: In this literature review, we searched MEDLINE a database using the following keywords: Cesarean section AND (operating room environment OR Noise OR Music OR Video recording OR Light level OR Gentle OR Temperature OR Motion Data). Eligible studies had to be published in English or French within the past 10 years and had to investigate the operating room environment during cesarean sections in women. For each study we reported which aspects of the physical environment were investigated in the OR (i.e., noise, music, movement, light or temperature) and the involved sensors. RESULTS: Of a total of 105 studies screened, we selected 8 articles from title and abstract in PubMed. This small number shows that the field is poorly investigated. The most evaluated environment factors to date are operating room noise and temperature, and the presence of music. Few studies used advanced sensors in the operating room to evaluate environmental factors in a more nuanced and complete way. Two studies concern the sound level, four concern music, one concerns temperature and one analyzed the number of entrances/exits into the OR. No study analyzed light level or more fine-grained movement data. CONCLUSIONS: Main findings include increase of noise and motion at specific time-points, for example during delivery or anaesthesia; the positive impact of music on parents and staff alike; and that a warmer theatre is better for babies but more uncomfortable for surgeons.


Assuntos
Cesárea , Obstetrícia , Recém-Nascido , Gravidez , Humanos , Feminino , Salas Cirúrgicas , Temperatura , Mães
6.
Int J Comput Assist Radiol Surg ; 18(7): 1269-1277, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37249748

RESUMO

PURPOSE: Many neurosurgical planning tasks rely on identifying points of interest in volumetric images. Often, these points require significant expertise to identify correctly as, in some cases, they are not visible but instead inferred by the clinician. This leads to a high degree of variability between annotators selecting these points. In particular, errors of type are when the experts fundamentally select different points rather than the same point with some inaccuracy. This complicates research as their mean may not reflect any of the experts' intentions nor the ground truth. METHODS: We present a regularised Bayesian model for measuring errors of type in pointing tasks. This model is reference-free; in that it does not require a priori knowledge of the ground truth point but instead works on the basis of the level of consensus between multiple annotators. We apply this model to simulated data and clinical data from transcranial magnetic stimulation for chronic pain. RESULTS: Our model estimates the probabilities of selecting the correct point in the range of 82.6[Formula: see text]88.6% with uncertainties in the range of 2.8[Formula: see text]4.0%. This agrees with the literature where ground truth points are known. The uncertainty has not previously been explored in the literature and gives an indication of the dataset's strength. CONCLUSIONS: Our reference-free Bayesian framework easily models errors of type in pointing tasks. It allows for clinical studies to be performed with a limited number of annotators where the ground truth is not immediately known, which can be applied widely for better understanding human errors in neurosurgical planning.


Assuntos
Teorema de Bayes , Humanos , Probabilidade , Incerteza
8.
J Med Imaging (Bellingham) ; 9(4): 045001, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35836671

RESUMO

Purpose: Deep brain stimulation (DBS) is an interventional treatment for some neurological and neurodegenerative diseases. For example, in Parkinson's disease, DBS electrodes are positioned at particular locations within the basal ganglia to alleviate the patient's motor symptoms. These interventions depend greatly on a preoperative planning stage in which potential targets and electrode trajectories are identified in a preoperative MRI. Due to the small size and low contrast of targets such as the subthalamic nucleus (STN), their segmentation is a difficult task. Machine learning provides a potential avenue for development, but it has difficulty in segmenting such small structures in volumetric images due to additional problems such as segmentation class imbalance. Approach: We present a two-stage separable learning workflow for STN segmentation consisting of a localization step that detects the STN and crops the image to a small region and a segmentation step that delineates the structure within that region. The goal of this decoupling is to improve accuracy and efficiency and to provide an intermediate representation that can be easily corrected by a clinical user. This correction capability was then studied through a human-computer interaction experiment with seven novice participants and one expert neurosurgeon. Results: Our two-step segmentation significantly outperforms the comparative registration-based method currently used in clinic and approaches the fundamental limit on variability due to the image resolution. In addition, the human-computer interaction experiment shows that the additional interaction mechanism allowed by separating STN segmentation into two steps significantly improves the users' ability to correct errors and further improves performance. Conclusions: Our method shows that separable learning not only is feasible for fully automatic STN segmentation but also leads to improved interactivity that can ease its translation into clinical use.

9.
Hum Brain Mapp ; 43(16): 4835-4851, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35841274

RESUMO

Extracting population-wise information from medical images, specifically in the neurological domain, is crucial to better understanding disease processes and progression. This is frequently done in a whole-brain voxel-wise manner, in which a population of patients and healthy controls are registered to a common co-ordinate space and a statistical test is performed on the distribution of image intensities for each location. Although this method has yielded a number of scientific insights, it is further from clinical applicability as the differences are often small and altogether do not permit for a high-performing classifier. In this article, we take the opposite approach of using a high-performing classifier, specifically a traditional convolutional neural network, and then extracting insights from it which can be applied in a population-wise manner, a method we call voxel-based diktiometry. We have applied this method to diffusion tensor imaging (DTI) analysis for Parkinson's disease (PD), using the Parkinson's Progression Markers Initiative database. By using the network sensitivity information, we can decompose what elements of the DTI contribute the most to the network's performance, drawing conclusions about diffusion biomarkers for PD that are based on metrics which are not readily expressed in the voxel-wise approach.


Assuntos
Imagem de Tensor de Difusão , Doença de Parkinson , Humanos , Imagem de Tensor de Difusão/métodos , Doença de Parkinson/diagnóstico por imagem , Encéfalo/diagnóstico por imagem , Redes Neurais de Computação
10.
Neuroimage Clin ; 35: 103079, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35700600

RESUMO

Disinhibition is a core symptom of many neurodegenerative diseases, particularly frontotemporal dementia, and is a major cause of stress for caregivers. While a distinction between behavioural and cognitive disinhibition is common, an operational definition of behavioural disinhibition is still missing. Furthermore, conventional assessment of behavioural disinhibition, based on questionnaires completed by the caregivers, often lacks ecological validity. Therefore, their neuroanatomical correlates are non-univocal. In the present work, we used an original behavioural approach in a semi-ecological situation to assess two specific dimensions of behavioural disinhibition: compulsivity and social disinhibition. First, we investigated disinhibition profile in patients compared to controls. Then, to validate our approach, compulsivity and social disinhibition scores were correlated with classic cognitive tests measuring disinhibition (Hayling Test) and social cognition (mini-Social cognition & Emotional Assessment). Finally, we disentangled the anatomical networks underlying these two subtypes of behavioural disinhibition, taking in account the grey (voxel-based morphometry) and white matter (diffusion tensor imaging tractography). We included 17 behavioural variant frontotemporal dementia patients and 18 healthy controls. We identified patients as more compulsive and socially disinhibited than controls. We found that behavioural metrics in the semi-ecological task were related to cognitive performance: compulsivity correlated with the Hayling test and both compulsivity and social disinhibition were associated with the emotion recognition test. Based on voxel-based morphometry and tractography, compulsivity correlated with atrophy in the bilateral orbitofrontal cortex, the right temporal region and subcortical structures, as well as with alterations of the bilateral cingulum and uncinate fasciculus, the right inferior longitudinal fasciculus and the right arcuate fasciculus. Thus, the network of regions related to compulsivity matched the "semantic appraisal" network. Social disinhibition was associated with bilateral frontal atrophy and impairments in the forceps minor, the bilateral cingulum and the left uncinate fasciculus, regions corresponding to the frontal component of the "salience" network. Summarizing, this study validates our semi-ecological approach, through the identification of two subtypes of behavioural disinhibition, and highlights different neural networks underlying compulsivity and social disinhibition. Taken together, these findings are promising for clinical practice by providing a better characterisation of inhibition disorders, promoting their detection and consequently a more adapted management of patients.


Assuntos
Demência Frontotemporal , Atrofia/patologia , Imagem de Tensor de Difusão , Lobo Frontal/patologia , Demência Frontotemporal/patologia , Humanos , Testes Neuropsicológicos
12.
J Addict Med ; 16(3): 340-345, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34510089

RESUMO

OBJECTIVES: To determine recent trends in: (1) human immunodeficiency virus (HIV) diagnoses, (2) the proportion of patients newly diagnosed with HIV with injection drug use (IDU) and (3) patients' patterns of healthcare utilization in the year before diagnosis at an urban, academic medical center. METHODS: We performed a cross sectional study of patients newly diagnosed with HIV at a healthcare system in southern New Jersey between January 1st, 2014 and December 31st, 2019. Patients 18 years or older with HIV diagnosed during the study period were included. Demographics, comorbidities, HIV test results, and healthcare utilization data were collected from the electronic medical record. RESULTS: Of 192 patients newly diagnosed with HIV, 36 (19%) had documented IDU. New HIV diagnoses doubled from 22 to 47 annual cases between 2014 and 2019. The proportion of patients with newly diagnosed HIV and documented IDU increased from 9% in 2014 to 32% in 2019, chi-square test for linear trend P value = 0.001. Eighty-nine percent of patients with IDU had at least one contact with the healthcare system in the year before diagnosis compared to 63% of patients without IDU, P value 0.003. The median (interquartile range IQR) number of healthcare visits was 7 [2 - 16] for patients with IDU versus 1 [0 - 3] for patients without IDU, P < 0.001. CONCLUSIONS: We observed an increase in new HIV diagnoses with an increase in the proportion of newly diagnosed patients with IDU. Patients with newly diagnosed HIV and IDU had high rates of health care utilization in the year before diagnosis presenting an opportunity for intervention.


Assuntos
Infecções por HIV , Abuso de Substâncias por Via Intravenosa , Estudos Transversais , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , Humanos , Aceitação pelo Paciente de Cuidados de Saúde , Abuso de Substâncias por Via Intravenosa/epidemiologia
13.
Artif Intell Med ; 122: 102198, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34823832

RESUMO

Deep Brain Stimulation (DBS) is an increasingly common therapy for a large range of neurological disorders, such as abnormal movement disorders. The effectiveness of DBS in terms of controlling patient symptomatology has made this procedure increasingly used over the past few decades. Concurrently, the popularity of Machine Learning (ML), a subfield of artificial intelligence, has skyrocketed and its influence has more recently extended to medical domains such as neurosurgery. Despite its growing research interest, there has yet to be a literature review specifically on the use of ML in DBS. We have followed a fully systematic methodology to obtain a corpus of 73 papers. In each paper, we identified the clinical application, the type/amount of data used, the method employed, and the validation strategy, further decomposed into 12 different sub-categories. The papers overall illustrated some existing trends in how ML is used in the context of DBS, including the breath of the problem domain and evolving techniques, as well as common frameworks and limitations. This systematic review analyzes at a broad level how ML have been recently used to address clinical problems on DBS, giving insight into how these new computational methods are helping to push the state-of-the-art of functional neurosurgery. DBS clinical workflow is complex, involves many specialists, and raises several clinical issues which have partly been addressed with artificial intelligence. However, several areas remain and those that have been recently addressed with ML are by no means considered "solved" by the community nor are they closed to new and evolving methods.


Assuntos
Estimulação Encefálica Profunda , Inteligência Artificial , Estimulação Encefálica Profunda/métodos , Humanos , Aprendizado de Máquina , Procedimentos Neurocirúrgicos/métodos
14.
Int J Comput Assist Radiol Surg ; 16(8): 1361-1370, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34216319

RESUMO

PURPOSE: Deep Brain Stimulation (DBS) is a proven therapy for Parkinson's Disease (PD), frequently resulting in an enhancement of motor function. Nonetheless, several undesirable side effects can occur after DBS, which can worsen the quality of life of the patient. Thus, the clinical team has to carefully select patients on whom to perform DBS. Over the past decade, there have been some attempts to relate pre-operative data and DBS clinical outcomes, with most focused on the motor symptomatology. In this paper, we propose a machine learning-based method able to predict a large number of DBS clinical outcomes for PD. METHODS: We propose a multimodal pipeline, referred to as PassFlow, which predicts 84 clinical post-operative clinical scores. PassFlow is composed of an artificial neural network to compress clinical information, an image processing method from the state-of-the-art to extract morphological biomarkers our of T1 imaging, and an SVM to perform the regressions. We validated PassFlow on 196 PD patients who undergone a DBS. RESULTS: PassFlow showed correlation coefficients as high as 0.71 and were able to significantly predict 63 out of the 84 scores, outperforming a comparative linear method. The number of metrics that are predicted with this pre-operative information was also found to be correlated with the number of patients with this information available, indicating that the PassFlow method is still actively learning. CONCLUSION: We presented a novel, machine learning-based pipeline to predict a variety of post-operative clinical outcomes of DBS for PD patients. PassFlow took into account various bio-markers, arising from different data modalities, showing high correlation coefficients for some scores from pre-operative data only. It indicates that many clinical outcomes of DBS can be predicted agnostic to the specific simulation parameters, as PassFlow has been validated without such stimulation-related information.


Assuntos
Estimulação Encefálica Profunda/métodos , Aprendizado de Máquina , Doença de Parkinson/terapia , Qualidade de Vida , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico
15.
Int J Comput Assist Radiol Surg ; 16(8): 1371-1379, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34117594

RESUMO

PURPOSE: Deep brain stimulation (DBS) is a common treatment for a variety of neurological disorders which involves the precise placement of electrodes at particular subcortical locations such as the subthalamic nucleus. This placement is often guided by auditory analysis of micro-electrode recordings (MERs) which informs the clinical team as to the anatomic region in which the electrode is currently positioned. Recent automation attempts have lacked flexibility in terms of the amount of signal recorded, not allowing them to collect more signal when higher certainty is needed or less when the anatomy is unambiguous. METHODS: We have addressed this problem by evaluating a simple algorithm that allows for MER signal collection to terminate once the underlying model has sufficient confidence. We have parameterized this approach and explored its performance using three underlying models composed of one neural network and two Bayesian extensions of said network. RESULTS: We have shown that one particular configuration, a Bayesian model of the underlying network's certainty, outperforms the others and is relatively insensitive to parameterization. Further investigation shows that this model also allows for signals to be classified earlier without increasing the error rate. CONCLUSION: We have presented a simple algorithm that records the confidence of an underlying neural network, thus allowing for MER data collection to be terminated early when sufficient confidence is reached. This has the potential to improve the efficiency of DBS electrode implantation by reducing the time required to identify anatomical structures using MERs.


Assuntos
Adaptação Fisiológica/fisiologia , Algoritmos , Percepção Auditiva/fisiologia , Estimulação Encefálica Profunda/métodos , Eletrodos Implantados , Doença de Parkinson/terapia , Teorema de Bayes , Humanos , Masculino , Núcleo Subtalâmico
16.
Int J Comput Assist Radiol Surg ; 16(7): 1077-1087, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34089439

RESUMO

PURPOSE: Transcranial magnetic stimulation (TMS) is a growing therapy for a variety of psychiatric and neurological disorders that arise from or are modulated by cortical regions of the brain represented by singular 3D target points. These target points are often determined manually with assistance from a pre-operative T1-weighted MRI, although there is growing interest in automatic target point localisation using an atlas. However, both approaches can be time-consuming which has an effect on the clinical workflow, and the latter does not take into account patient variability such as the varying number of cortical gyri where these targets are located. METHODS: This paper proposes a multi-resolution convolutional neural network for point localisation in MR images for a priori defined points in increasingly finely resolved versions of the input image. This approach is both fast and highly memory efficient, allowing it to run in high-throughput centres, and has the capability of distinguishing between patients with high levels of anatomical variability. RESULTS: Preliminary experiments have found the accuracy of this network to be [Formula: see text] mm, compared to [Formula: see text] mm for deformable registration and [Formula: see text] mm for a human expert. For most treatment points, the human expert and proposed CNN statistically significantly outperform registration, but neither statistically significantly outperforms the other, suggesting that the proposed network has human-level performance. CONCLUSIONS: The human-level performance of this network indicates that it can improve TMS planning by automatically localising target points in seconds, avoiding more time-consuming registration or manual point localisation processes. This is particularly beneficial for out-of-hospital centres with limited computational resources where TMS is increasingly being administered.


Assuntos
Encéfalo/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Imageamento por Ressonância Magnética/métodos , Doenças do Sistema Nervoso/terapia , Redes Neurais de Computação , Estimulação Magnética Transcraniana/métodos , Humanos , Doenças do Sistema Nervoso/diagnóstico , Reprodutibilidade dos Testes
17.
Front Microbiol ; 12: 640408, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33995300

RESUMO

Klebsiella is a genus of Gram-negative bacteria known to be opportunistic pathogens that may cause a variety of infections in humans. Highly drug-resistant Klebsiella species, especially K. pneumoniae, have emerged rapidly and are becoming a major concern in clinical management. Although K. pneumoniae is considered the most important pathogen within the genus, the true clinical significance of the other species is likely underrecognized due to the inability of conventional microbiological methods to distinguish between the species leading to high rates of misidentification. Bacterial whole-genome sequencing (WGS) enables precise species identification and characterization that other technologies do not allow. Herein, we have characterized the diversity and traits of Klebsiella spp. in community-onset infections by WGS of clinical isolates (n = 105) collected during a prospective sepsis study in Sweden. The sequencing revealed that 32 of the 82 isolates (39.0%) initially identified as K. pneumoniae with routine microbiological methods based on cultures followed by matrix-assisted laser desorption-time of flight mass spectrometry (MALDI-TOF MS) had been misidentified. Of these, 23 were identified as Klebsiella variicola and nine as other members of the K. pneumoniae complex. Comparisons of the number of resistance genes showed that significantly fewer resistance genes were detected in Klebsiella oxytoca compared to K. pneumoniae and K. variicola (both values of p < 0.001). Moreover, a high proportion of the isolates within the K. pneumoniae complex were predicted to be genotypically multidrug-resistant (MDR; 79/84, 94.0%) in contrast to K. oxytoca (3/16, 18.8%) and Klebsiella michiganensis (0/4, 0.0%). All isolates predicted as genotypically MDR were found to harbor the combination of ß-lactam, fosfomycin, and quinolone resistance markers. Multi-locus sequence typing (MLST) revealed a high diversity of sequence types among the Klebsiella spp. with ST14 (10.0%) and ST5429 (10.0%) as the most prevalent ones for K. pneumoniae, ST146 for K. variicola (12.0%), and ST176 for K. oxytoca (25.0%). In conclusion, the results from this study highlight the importance of using high-resolution genotypic methods for identification and characterization of clinical Klebsiella spp. isolates. Our findings indicate that infections caused by other members of the K. pneumoniae complex than K. pneumoniae are a more common clinical problem than previously described, mainly due to high rates of misidentifications.

18.
Artif Intell Med ; 114: 102051, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33875162

RESUMO

Medical questionnaires are a valuable source of information but are often difficult to analyse due to both their size and the high possibility of them having missing values. This is a problematic issue in biomedical data science as it may complicate how individual questionnaire data is represented for statistical or machine learning analysis. In this paper, we propose a deeply-learnt residual autoencoder to simultaneously perform non-linear data imputation and dimensionality reduction. We present an extensive analysis of the dynamics of the performance of this autoencoder regarding the compression rate and the proportion of missing values. This method is evaluated on motor and non-motor clinical questionnaires of the Parkinson's Progression Markers Initiative (PPMI) database and consistently outperforms linear coupled imputation and reduction approaches.


Assuntos
Compressão de Dados , Doença de Parkinson , Bases de Dados Factuais , Progressão da Doença , Humanos , Doença de Parkinson/diagnóstico , Inquéritos e Questionários
19.
Age Ageing ; 50(4): 1064-1068, 2021 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-33837764

RESUMO

Heart failure (HF) can be considered a disease of older people. It is a leading cause of hospitalisation and is associated with high rates of morbidity and mortality in the over-65s. In 2012, an editorial in this journal detailed the latest HF research and guidelines, calling for greater integration of geriatricians in HF care. This current article reflects upon what has been achieved in this field in recent years, highlighting some future challenges and promising areas. It is written from the perspective of one such integrated team and explores the new role of cardiogeriatrician, working in a multidisciplinary team to deliver and improve care to increasingly complex, older, frail patients with multiple comorbidities who present with primary cardiology problems, especially decompensated HF. Geriatric liaison has improved the care of frail patients in orthopaedics, cancer services, stroke, acute medicine and numerous community settings. We propose that this vital role should now be extended to cardiology teams in general and to HF in particular.


Assuntos
Cardiologia , Insuficiência Cardíaca , Idoso , Comorbidade , Geriatras , Insuficiência Cardíaca/diagnóstico , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/terapia , Hospitalização , Humanos
20.
AIDS Care ; 33(11): 1507-1513, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33103919

RESUMO

This prospective cohort study enrolled people living with HIV initiating antiretroviral therapy (ART) containing the integrase inhibitors, dolutegravir (DTG) or elvitegravir (EVG) and administered the Montreal Cognitive Assessment (MoCA) at baseline and again after approximately six months to compare changes in MoCA scores. The proportion of patients found to have cognitive impairment, as indicated by a MoCA score <26/30, on each agent were also compared and comparisons were made between changes in each domain assessed by the MoCA (visuospatial/executive, naming, attention, language, abstraction, delayed recall, and orientation). Thirty-five evaluable participants were enrolled, 18 on DTG and 17 on EVG. The median [interquartile range(IQR)] age was 44 (32 to 54) years, 63% were male, 57% were African American. The median (IQR) MoCA score at baseline was 25 (23 to 27) with no difference between groups (p=0.249). The median (IQR) change in MoCA score was 0 (-1 to 2) for DTG and 1 (0 to 3) for EVG (p = 0.183). Of those on DTG, 8 (44%) had MoCA scores <26 on follow-up compared to 11 (65%) on EVG (p = 0.229). There were no significant differences in changes in any of the individual MoCA domains.


Assuntos
Infecções por HIV , Inibidores de Integrase de HIV , HIV-1 , Adulto , Infecções por HIV/tratamento farmacológico , Inibidores de Integrase de HIV/uso terapêutico , Compostos Heterocíclicos com 3 Anéis , Humanos , Masculino , Pessoa de Meia-Idade , Oxazinas , Piperazinas , Estudos Prospectivos , Piridonas , Quinolonas
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