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2.
J Med Internet Res ; 25: e45767, 2023 09 19.
Artigo em Inglês | MEDLINE | ID: mdl-37725432

RESUMO

BACKGROUND: While scientific knowledge of post-COVID-19 condition (PCC) is growing, there remains significant uncertainty in the definition of the disease, its expected clinical course, and its impact on daily functioning. Social media platforms can generate valuable insights into patient-reported health outcomes as the content is produced at high resolution by patients and caregivers, representing experiences that may be unavailable to most clinicians. OBJECTIVE: In this study, we aimed to determine the validity and effectiveness of advanced natural language processing approaches built to derive insight into PCC-related patient-reported health outcomes from social media platforms Twitter and Reddit. We extracted PCC-related terms, including symptoms and conditions, and measured their occurrence frequency. We compared the outputs with human annotations and clinical outcomes and tracked symptom and condition term occurrences over time and locations to explore the pipeline's potential as a surveillance tool. METHODS: We used bidirectional encoder representations from transformers (BERT) models to extract and normalize PCC symptom and condition terms from English posts on Twitter and Reddit. We compared 2 named entity recognition models and implemented a 2-step normalization task to map extracted terms to unique concepts in standardized terminology. The normalization steps were done using a semantic search approach with BERT biencoders. We evaluated the effectiveness of BERT models in extracting the terms using a human-annotated corpus and a proximity-based score. We also compared the validity and reliability of the extracted and normalized terms to a web-based survey with more than 3000 participants from several countries. RESULTS: UmlsBERT-Clinical had the highest accuracy in predicting entities closest to those extracted by human annotators. Based on our findings, the top 3 most commonly occurring groups of PCC symptom and condition terms were systemic (such as fatigue), neuropsychiatric (such as anxiety and brain fog), and respiratory (such as shortness of breath). In addition, we also found novel symptom and condition terms that had not been categorized in previous studies, such as infection and pain. Regarding the co-occurring symptoms, the pair of fatigue and headaches was among the most co-occurring term pairs across both platforms. Based on the temporal analysis, the neuropsychiatric terms were the most prevalent, followed by the systemic category, on both social media platforms. Our spatial analysis concluded that 42% (10,938/26,247) of the analyzed terms included location information, with the majority coming from the United States, United Kingdom, and Canada. CONCLUSIONS: The outcome of our social media-derived pipeline is comparable with the results of peer-reviewed articles relevant to PCC symptoms. Overall, this study provides unique insights into patient-reported health outcomes of PCC and valuable information about the patient's journey that can help health care providers anticipate future needs. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): RR2-10.1101/2022.12.14.22283419.


Assuntos
COVID-19 , Mídias Sociais , Humanos , Processamento de Linguagem Natural , Reprodutibilidade dos Testes , Fadiga , Medidas de Resultados Relatados pelo Paciente
3.
J Immunol ; 208(3): 633-641, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-35031579

RESUMO

Calcitonin gene-related peptide (CGRP) can bias the outcome of Ag presentation to responsive T cells in vitro away from Th1-type immunity and toward the Th2 and Th17 poles through actions on endothelial cells (ECs). To test the in vivo significance of this observation, we engineered a mouse lacking functional CGRP receptors on ECs (EC receptor activity modifying protein 1 [RAMP1] knockout mice). On percutaneous immunization to 1-fluoro-2,4-dinitrobenzene, stimulated CD4+ T cells from draining lymph nodes showed significantly reduced IL-17A expression with significantly increased IFN-γ, IL-4, and IL-22 expression at the protein and mRNA levels compared with control mice. Retinoic acid receptor-related orphan receptor γ t mRNA was significantly reduced, while mRNAs for T-box expressed in T cells and GATA binding protein 3 were significantly increased. In addition, EC RAMP1 knockout mice had significantly reduced contact hypersensitivity responses, and systemic administration of a CGRP receptor antagonist similarly inhibited contact hypersensitivity in wild-type mice. These observations provide compelling evidence that CGRP is a key regulator of cutaneous immunity through effects on ECs and suggest a novel pathway for potential therapeutic manipulation.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina/genética , Dermatite de Contato/imunologia , Células Endoteliais/imunologia , Proteína 1 Modificadora da Atividade de Receptores/genética , Pele/imunologia , Animais , Apresentação de Antígeno/imunologia , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Dinitrofluorbenzeno/imunologia , Fator de Transcrição GATA3/metabolismo , Interferon gama/biossíntese , Interleucina-17/biossíntese , Interleucina-4/biossíntese , Interleucinas/biossíntese , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Membro 1 do Grupo F da Subfamília 1 de Receptores Nucleares/genética , Células Th1/imunologia , Células Th17/imunologia , Células Th2/imunologia , Interleucina 22
4.
J Am Acad Dermatol ; 86(5): 1072-1079, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-33515627

RESUMO

Endocrine mucin-producing sweat gland carcinoma is a low-grade eyelid tumor. Small biopsies and insensitive immunohistochemistry predispose to misdiagnosis. We aimed to identify clarifying immunohistochemical markers, molecular markers, or both. Clinicopathologic data (22 cases) were reviewed. Immunohistochemistry (insulinoma-associated protein 1, BCL-2, mucin 2 [MUC2], mucin 4, androgen receptor, ß-catenin, and Merkel cell polyomavirus) and next-generation sequencing (Memorial Sloan Kettering integrated mutation profiling of actionable cancer targets, 468 genes) were performed (3 cases). Female patients (n = 15) and male patients (n = 7) (mean age 71.8 years; range 53-88 years) had eyelid or periorbital tumors (>90%) with mucin-containing solid or cystic neuroendocrine pathology. Immunohistochemistry (insulinoma-associated protein 1, BCL2, androgen receptor, retinoblastoma-associated protein 1, and ß-catenin) was diffusely positive (5/5), MUC2 partial, mucin 4 focal, and Merkel cell polyomavirus negative. Memorial Sloan Kettering integrated mutation profiling of actionable cancer targets identified 12 single-nucleotide variants and 1 in-frame deletion in 3 cases, each with DNA damage response or repair (BRD4, PPP4R2, and RTEL1) and tumor-suppressor pathway (BRD4, TP53, TSC1, and LATS2) mutations. Microsatellite instability, copy number alterations, and structural alterations were absent. Insulinoma-associated protein 1 and MUC2 are positive in endocrine mucin-producing sweat gland carcinoma. MUC2 positivity suggests conjunctival origin. Multistep pathogenesis involving DNA damage repair and tumor-suppressor pathways may be implicated.


Assuntos
Carcinoma de Apêndice Cutâneo , Insulinoma , Poliomavírus das Células de Merkel , Neoplasias Pancreáticas , Neoplasias Cutâneas , Neoplasias das Glândulas Sudoríparas , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Proteínas de Ciclo Celular , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mucina-2/genética , Mucina-2/metabolismo , Mucina-4/genética , Mucinas/metabolismo , Mutação , Proteínas Nucleares/genética , Proteínas Serina-Treonina Quinases , Receptores Androgênicos/genética , Proteínas Repressoras , Neoplasias Cutâneas/genética , Neoplasias das Glândulas Sudoríparas/diagnóstico , Neoplasias das Glândulas Sudoríparas/genética , Glândulas Sudoríparas/patologia , Fatores de Transcrição/genética , Proteínas Supressoras de Tumor , beta Catenina/genética
5.
IEEE Trans Biomed Eng ; 68(7): 2313-2325, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33784612

RESUMO

OBJECTIVE: Individuals with neurological disease or injury such as amyotrophic lateral sclerosis, spinal cord injury or stroke may become tetraplegic, unable to speak or even locked-in. For people with these conditions, current assistive technologies are often ineffective. Brain-computer interfaces are being developed to enhance independence and restore communication in the absence of physical movement. Over the past decade, individuals with tetraplegia have achieved rapid on-screen typing and point-and-click control of tablet apps using intracortical brain-computer interfaces (iBCIs) that decode intended arm and hand movements from neural signals recorded by implanted microelectrode arrays. However, cables used to convey neural signals from the brain tether participants to amplifiers and decoding computers and require expert oversight, severely limiting when and where iBCIs could be available for use. Here, we demonstrate the first human use of a wireless broadband iBCI. METHODS: Based on a prototype system previously used in pre-clinical research, we replaced the external cables of a 192-electrode iBCI with wireless transmitters and achieved high-resolution recording and decoding of broadband field potentials and spiking activity from people with paralysis. Two participants in an ongoing pilot clinical trial completed on-screen item selection tasks to assess iBCI-enabled cursor control. RESULTS: Communication bitrates were equivalent between cabled and wireless configurations. Participants also used the wireless iBCI to control a standard commercial tablet computer to browse the web and use several mobile applications. Within-day comparison of cabled and wireless interfaces evaluated bit error rate, packet loss, and the recovery of spike rates and spike waveforms from the recorded neural signals. In a representative use case, the wireless system recorded intracortical signals from two arrays in one participant continuously through a 24-hour period at home. SIGNIFICANCE: Wireless multi-electrode recording of broadband neural signals over extended periods introduces a valuable tool for human neuroscience research and is an important step toward practical deployment of iBCI technology for independent use by individuals with paralysis. On-demand access to high-performance iBCI technology in the home promises to enhance independence and restore communication and mobility for individuals with severe motor impairment.


Assuntos
Interfaces Cérebro-Computador , Encéfalo , Mãos , Humanos , Microeletrodos , Quadriplegia
6.
Sci Rep ; 11(1): 98, 2021 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-33431994

RESUMO

Intracortical brain-computer interfaces (iBCIs) allow people with paralysis to directly control assistive devices using neural activity associated with the intent to move. Realizing the full potential of iBCIs critically depends on continued progress in understanding how different cortical areas contribute to movement control. Here we present the first comparison between neuronal ensemble recordings from the left middle frontal gyrus (MFG) and precentral gyrus (PCG) of a person with tetraplegia using an iBCI. As expected, PCG was more engaged in selecting and generating intended movements than in earlier perceptual stages of action planning. By contrast, MFG displayed movement-related information during the sensorimotor processing steps preceding the appearance of the action plan in PCG, but only when the actions were instructed using auditory cues. These results describe a previously unreported function for neurons in the human left MFG in auditory processing contributing to motor control.


Assuntos
Estimulação Acústica , Córtex Auditivo/fisiopatologia , Movimento/fisiologia , Córtex Pré-Frontal/fisiopatologia , Quadriplegia/fisiopatologia , Adulto , Interfaces Cérebro-Computador , Sinais (Psicologia) , Eletrodos Implantados , Lobo Frontal/fisiopatologia , Humanos , Masculino , Microeletrodos , Neurônios/fisiologia , Tecnologia Assistiva
7.
Acta Neuropathol Commun ; 8(1): 80, 2020 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-32493417

RESUMO

BCOR has been recognized as a recurrently altered gene in a subset of pediatric tumors of the central nervous system (CNS). Here, we describe a novel BCOR-CREBBP fusion event in a case of pediatric infiltrating astrocytoma and further probe the frequency of related fusion events in CNS tumors. We analyzed biopsy samples taken from a 15-year-old male with an aggressive, unresectable and multifocal infiltrating astrocytoma. We performed RNA sequencing (RNA-seq) and targeted DNA sequencing. In the index case, the fused BCOR-CREBBP transcript comprises exons 1-4 of BCOR and exon 31 of CREBBP. The fused gene thus retains the Bcl6 interaction domain of BCOR while eliminating the domain that has been shown to interact with the polycomb group protein PCGF1. The fusion event was validated by FISH and reverse transcriptase PCR. An additional set of 177 pediatric and adult primary CNS tumors were assessed via FISH for BCOR break apart events, all of which were negative. An additional 509 adult lower grade infiltrating gliomas from the publicly available TCGA dataset were screened for BCOR or CREBBP fusions. In this set, one case was found to harbor a CREBBP-GOLGA6L2 fusion and one case a CREBBP-SRRM2 fusion. In a third patient, both BCOR-L3MBTL2 and EP300-BCOR fusions were seen. Of particular interest to this study, EP300 is a paralog of CREBBP and the breakpoint seen involves a similar region of the gene to that of the index case; however, the resultant transcript is predicted to be completely distinct. While this gene fusion may play an oncogenic role through the loss of tumor suppressor functions of BCOR and CREBBP, further screening over larger cohorts and functional validation is needed to determine the degree to which this or similar fusions are recurrent and to elucidate their oncogenic potential.


Assuntos
Astrocitoma/genética , Neoplasias Encefálicas/genética , Proteína de Ligação a CREB/genética , Proteínas de Fusão Oncogênica/genética , Proteínas Proto-Oncogênicas/genética , Proteínas Repressoras/genética , Adolescente , Adulto , Astrocitoma/patologia , Encéfalo/patologia , Neoplasias Encefálicas/patologia , Feminino , Humanos , Masculino , Adulto Jovem
8.
Cell Rep ; 31(5): 107581, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32375031

RESUMO

The offline "replay" of neural firing patterns underlying waking experience, previously observed in non-human animals, is thought to be a mechanism for memory consolidation. Here, we test for replay in the human brain by recording spiking activity from the motor cortex of two participants who had intracortical microelectrode arrays placed chronically as part of a brain-computer interface pilot clinical trial. Participants took a nap before and after playing a neurally controlled sequence-copying game that consists of many repetitions of one "repeated" sequence sparsely interleaved with varying "control" sequences. Both participants performed repeated sequences more accurately than control sequences, consistent with learning. We compare the firing rate patterns that caused the cursor movements when performing each sequence to firing rate patterns throughout both rest periods. Correlations with repeated sequences increase more from pre- to post-task rest than do correlations with control sequences, providing direct evidence of learning-related replay in the human brain.


Assuntos
Aprendizagem/fisiologia , Consolidação da Memória/fisiologia , Córtex Motor/fisiologia , Descanso/fisiologia , Eletroencefalografia/métodos , Humanos , Neurônios/fisiologia , Sono/fisiologia , Vigília/fisiologia
9.
Sci Rep ; 10(1): 1429, 2020 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-31996696

RESUMO

Hybrid kinetic and kinematic intracortical brain-computer interfaces (iBCIs) have the potential to restore functional grasping and object interaction capabilities in individuals with tetraplegia. This requires an understanding of how kinetic information is represented in neural activity, and how this representation is affected by non-motor parameters such as volitional state (VoS), namely, whether one observes, imagines, or attempts an action. To this end, this work investigates how motor cortical neural activity changes when three human participants with tetraplegia observe, imagine, and attempt to produce three discrete hand grasping forces with the dominant hand. We show that force representation follows the same VoS-related trends as previously shown for directional arm movements; namely, that attempted force production recruits more neural activity compared to observed or imagined force production. Additionally, VoS-modulated neural activity to a greater extent than grasping force. Neural representation of forces was lower than expected, possibly due to compromised somatosensory pathways in individuals with tetraplegia, which have been shown to influence motor cortical activity. Nevertheless, attempted forces (but not always observed or imagined forces) could be decoded significantly above chance, thereby potentially providing relevant information towards the development of a hybrid kinetic and kinematic iBCI.


Assuntos
Córtex Motor/fisiologia , Próteses Neurais , Quadriplegia/terapia , Volição/fisiologia , Fenômenos Biomecânicos , Engenharia Biomédica , Interfaces Cérebro-Computador , Doença Crônica , Força da Mão , Humanos , Imaginação , Masculino , Microeletrodos , Pessoa de Meia-Idade , Córtex Motor/cirurgia , Recuperação de Função Fisiológica , Transmissão Sináptica
10.
Ann Diagn Pathol ; 44: 151414, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31778951

RESUMO

The small guanosine triphosphatase Rho and its target Rho kinase are involved in a heterogeneous spectrum of cellular activities, many of which are integral to cytoskeletal organization. Furthermore, the Rho kinases result in NF kappa beta activation and hence the induction of various pro-inflammatory cytokines including TNF-alpha, IL-1B and IL-6. ROCK2 is a downstream protein, whose expression is indicative of Rho Kinase activation. Given the diverse effects of Rho-kinase, including a potentially critical role in augmenting inflammation, ROCK2 expression was examined in biopsies of select autoimmune connective tissue diseases as compared to control diagnoses. Select cases of lupus erythematosus, dermatomyositis, autoimmune sclerodermoid disorders and Kohlmeier-Degos disease (a distinctive vasculopathy that occurs in the other aforesaid conditions but also as a forme fruste microvascular and arteriopathic syndrome) were studied. Control biopsies included normal skin and cutaneous inflammatory conditions unrelated to collagen vascular disease/autoimmune disease. We found ROCK2 expression significantly increased in biopsies of lupus erythematosus, dermatomyositis, scleroderma and Kohlmeier-Degos disease. A pattern emerged of consistent marked ROCK2 upregulation in endothelium and variable expression in inflammatory cells and epithelium. While expression was undetectable in normal skin, it was found in inflamed skin unrelated to specific autoimmune disease. The staining pattern could approach that seen in study group cases but was less pronounced and preferentially upregulated in the endothelium, with a lesser extent of staining in the epidermis and inflammatory cells. Rho kinase is a driving factor in diverse cutaneous diseases especially autoimmune disease and Kohlmeier-Degos disease. This significantly upregulated pathway defines a potential target for biologic therapy.


Assuntos
Doenças Autoimunes/enzimologia , Papulose Atrófica Maligna/enzimologia , Transdução de Sinais , Dermatopatias/enzimologia , Quinases Associadas a rho/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Doenças Autoimunes/patologia , Pré-Escolar , Feminino , Regulação Enzimológica da Expressão Gênica , Humanos , Lactente , Inflamação , Masculino , Papulose Atrófica Maligna/patologia , Pessoa de Meia-Idade , Dermatopatias/patologia , Adulto Jovem , Quinases Associadas a rho/genética
11.
Sci Rep ; 9(1): 8881, 2019 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-31222030

RESUMO

Decoders optimized offline to reconstruct intended movements from neural recordings sometimes fail to achieve optimal performance online when they are used in closed-loop as part of an intracortical brain-computer interface (iBCI). This is because typical decoder calibration routines do not model the emergent interactions between the decoder, the user, and the task parameters (e.g. target size). Here, we investigated the feasibility of simulating online performance to better guide decoder parameter selection and design. Three participants in the BrainGate2 pilot clinical trial controlled a computer cursor using a linear velocity decoder under different gain (speed scaling) and temporal smoothing parameters and acquired targets with different radii and distances. We show that a user-specific iBCI feedback control model can predict how performance changes under these different decoder and task parameters in held-out data. We also used the model to optimize a nonlinear speed scaling function for the decoder. When used online with two participants, it increased the dynamic range of decoded speeds and decreased the time taken to acquire targets (compared to an optimized standard decoder). These results suggest that it is feasible to simulate iBCI performance accurately enough to be useful for quantitative decoder optimization and design.


Assuntos
Biorretroalimentação Psicológica , Interfaces Cérebro-Computador , Modelos Neurológicos , Algoritmos , Calibragem , Humanos , Desempenho Psicomotor
12.
J Neurophysiol ; 121(4): 1428-1450, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30785814

RESUMO

Intracortical brain-computer interfaces (BCIs) can enable individuals to control effectors, such as a computer cursor, by directly decoding the user's movement intentions from action potentials and local field potentials (LFPs) recorded within the motor cortex. However, the accuracy and complexity of effector control achieved with such "biomimetic" BCIs will depend on the degree to which the intended movements used to elicit control modulate the neural activity. In particular, channels that do not record distinguishable action potentials and only record LFP modulations may be of limited use for BCI control. In contrast, a biofeedback approach may surpass these limitations by letting the participants generate new control signals and learn strategies that improve the volitional control of signals used for effector control. Here, we show that, by using a biofeedback paradigm, three individuals with tetraplegia achieved volitional control of gamma LFPs (40-400 Hz) recorded by a single microelectrode implanted in the precentral gyrus. Control was improved over a pair of consecutive sessions up to 3 days apart. In all but one session, the channel used to achieve control lacked distinguishable action potentials. Our results indicate that biofeedback LFP-based BCIs may potentially contribute to the neural modulation necessary to obtain reliable and useful control of effectors. NEW & NOTEWORTHY Our study demonstrates that people with tetraplegia can volitionally control individual high-gamma local-field potential (LFP) channels recorded from the motor cortex, and that this control can be improved using biofeedback. Motor cortical LFP signals are thought to be both informative and stable intracortical signals and, thus, of importance for future brain-computer interfaces.


Assuntos
Interfaces Cérebro-Computador , Ritmo Gama , Córtex Motor/fisiopatologia , Quadriplegia/fisiopatologia , Adulto , Eletrodos Implantados/efeitos adversos , Eletrodos Implantados/normas , Retroalimentação Fisiológica , Humanos , Movimento , Quadriplegia/reabilitação
13.
PLoS One ; 13(11): e0204566, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30462658

RESUMO

General-purpose computers have become ubiquitous and important for everyday life, but they are difficult for people with paralysis to use. Specialized software and personalized input devices can improve access, but often provide only limited functionality. In this study, three research participants with tetraplegia who had multielectrode arrays implanted in motor cortex as part of the BrainGate2 clinical trial used an intracortical brain-computer interface (iBCI) to control an unmodified commercial tablet computer. Neural activity was decoded in real time as a point-and-click wireless Bluetooth mouse, allowing participants to use common and recreational applications (web browsing, email, chatting, playing music on a piano application, sending text messages, etc.). Two of the participants also used the iBCI to "chat" with each other in real time. This study demonstrates, for the first time, high-performance iBCI control of an unmodified, commercially available, general-purpose mobile computing device by people with tetraplegia.


Assuntos
Ondas Encefálicas , Interfaces Cérebro-Computador , Computadores de Mão , Quadriplegia , Software , Adulto , Eletrodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
IEEE Trans Biomed Eng ; 65(9): 2066-2078, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29989927

RESUMO

OBJECTIVE: Recent reports indicate that making better assumptions about the user's intended movement can improve the accuracy of decoder calibration for intracortical brain-computer interfaces. Several methods now exist for estimating user intent, including an optimal feedback control model, a piecewise-linear feedback control model, ReFIT, and other heuristics. Which of these methods yields the best decoding performance? METHODS: Using data from the BrainGate2 pilot clinical trial, we measured how a steady-state velocity Kalman filter decoder was affected by the choice of intention estimation method. We examined three separate components of the Kalman filter: dimensionality reduction, temporal smoothing, and output gain (speed scaling). RESULTS: The decoder's dimensionality reduction properties were largely unaffected by the intention estimation method. Decoded velocity vectors differed by <5% in terms of angular error and speed vs. target distance curves across methods. In contrast, the smoothing and gain properties of the decoder were greatly affected (> 50% difference in average values). Since the optimal gain and smoothing properties are task-specific (e.g. lower gains are better for smaller targets but worse for larger targets), no one method was better for all tasks. CONCLUSION: Our results show that, when gain and smoothing differences are accounted for, current intention estimation methods yield nearly equivalent decoders and that simple models of user intent, such as a position error vector (target position minus cursor position), perform comparably to more elaborate models. Our results also highlight that simple differences in gain and smoothing properties have a large effect on online performance and can confound decoder comparisons.


Assuntos
Interfaces Cérebro-Computador , Intenção , Córtex Motor/fisiologia , Processamento de Sinais Assistido por Computador , Algoritmos , Calibragem , Simulação por Computador , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Modelos Neurológicos , Movimento/fisiologia , Quadriplegia/reabilitação
15.
J Neurophysiol ; 120(1): 343-360, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29694279

RESUMO

Restoring communication for people with locked-in syndrome remains a challenging clinical problem without a reliable solution. Recent studies have shown that people with paralysis can use brain-computer interfaces (BCIs) based on intracortical spiking activity to efficiently type messages. However, due to neuronal signal instability, most intracortical BCIs have required frequent calibration and continuous assistance of skilled engineers to maintain performance. Here, an individual with locked-in syndrome due to brain stem stroke and an individual with tetraplegia secondary to amyotrophic lateral sclerosis (ALS) used a simple communication BCI based on intracortical local field potentials (LFPs) for 76 and 138 days, respectively, without recalibration and without significant loss of performance. BCI spelling rates of 3.07 and 6.88 correct characters/minute allowed the participants to type messages and write emails. Our results indicate that people with locked-in syndrome could soon use a slow but reliable LFP-based BCI for everyday communication without ongoing intervention from a technician or caregiver. NEW & NOTEWORTHY This study demonstrates, for the first time, stable repeated use of an intracortical brain-computer interface by people with tetraplegia over up to four and a half months. The approach uses local field potentials (LFPs), signals that may be more stable than neuronal action potentials, to decode participants' commands. Throughout the several months of evaluation, the decoder remained unchanged; thus no technical interventions were required to maintain consistent brain-computer interface operation.


Assuntos
Esclerose Lateral Amiotrófica/reabilitação , Interfaces Cérebro-Computador , Comunicação , Quadriplegia/reabilitação , Reabilitação do Acidente Vascular Cerebral/métodos , Acidente Vascular Cerebral/fisiopatologia , Esclerose Lateral Amiotrófica/complicações , Esclerose Lateral Amiotrófica/fisiopatologia , Tronco Encefálico/fisiopatologia , Potenciais Evocados , Humanos , Quadriplegia/fisiopatologia , Acidente Vascular Cerebral/etiologia , Reabilitação do Acidente Vascular Cerebral/instrumentação
16.
J Neural Eng ; 15(2): 026007, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29363625

RESUMO

OBJECTIVE: Brain-computer interfaces (BCIs) can enable individuals with tetraplegia to communicate and control external devices. Though much progress has been made in improving the speed and robustness of neural control provided by intracortical BCIs, little research has been devoted to minimizing the amount of time spent on decoder calibration. APPROACH: We investigated the amount of time users needed to calibrate decoders and achieve performance saturation using two markedly different decoding algorithms: the steady-state Kalman filter, and a novel technique using Gaussian process regression (GP-DKF). MAIN RESULTS: Three people with tetraplegia gained rapid closed-loop neural cursor control and peak, plateaued decoder performance within 3 min of initializing calibration. We also show that a BCI-naïve user (T5) was able to rapidly attain closed-loop neural cursor control with the GP-DKF using self-selected movement imagery on his first-ever day of closed-loop BCI use, acquiring a target 37 s after initiating calibration. SIGNIFICANCE: These results demonstrate the potential for an intracortical BCI to be used immediately after deployment by people with paralysis, without the need for user learning or extensive system calibration.


Assuntos
Interfaces Cérebro-Computador , Neuroestimuladores Implantáveis , Córtex Motor/fisiologia , Quadriplegia/terapia , Adulto , Interfaces Cérebro-Computador/tendências , Calibragem , Feminino , Humanos , Neuroestimuladores Implantáveis/tendências , Masculino , Pessoa de Meia-Idade , Quadriplegia/fisiopatologia , Fatores de Tempo
17.
Am J Dermatopathol ; 40(4): 259-264, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28654463

RESUMO

BACKGROUND: Melanoma is a potentially lethal form of skin cancer for which the current standard therapy is complete surgical removal of the primary tumor followed by sentinel lymph node biopsy when indicated. Histologic identification of metastatic melanoma in a sentinel node has significant prognostic and therapeutic implications, routinely guiding further surgical management with regional lymphadenectomy. While melanocytes in a lymph node can be identified by routine histopathologic and immunohistochemical examination, the distinction between nodal nevus cells and melanoma can be morphologically problematic. Previous studies have shown that malignant melanoma can over-express metabolic genes such as fatty acid synthase (FASN) and acetyl-CoA carboxylase (ACC). This immunohistochemical study aims to compare the utility of FASN and ACC in differentiating sentinel lymph nodes with metastatic melanomas from those with benign nodal nevi in patients with cutaneous melanoma. MATERIALS AND METHODS: Using antibodies against FASN and ACC, 13 sentinel lymph nodes from 13 patients with metastatic melanoma and 14 lymph nodes harboring benign intracapsular nevi from 14 patients with cutaneous malignant melanoma were examined. A diagnosis of nodal melanoma was based on cytologic atypia and histologic comparison with the primary melanoma. All nodal nevi were intracapsular and not trabecular. Immunohistochemistry for Melan-A, S100, human melanoma black 45 (HMB45), FASN, and ACC were performed. The percentage of melanocytes staining with HMB45, FASN, and ACC was determined and graded in 25% increments; staining intensity was graded as weak, moderate, or strong. RESULTS: All metastatic melanomas tested had at least 25% tumor cell staining for both FASN and ACC. Greater than 75% of the tumor cells stained with FAS in 7/13 cases and for ACC in 5/12 cases. Intensity of staining was variable; strong staining for FASN and ACC was observed in 69% and 50% of metastatic melanoma, respectively. HMB45 was negative in 40% of nodal melanoma cases all of which stained with FASN and ACC. Capsular nevi were uniformly negative for FASN, ACC, and HMB45 immunoreactivity. CONCLUSIONS: All metastatic melanoma cases involving sentinel lymph nodes were positive for FASN and ACC while no staining was observed in intracapsular nevi. These findings suggest that FASN and ACC could be used as valuable ancillary stains in the distinction between nodal nevi and metastatic melanoma.


Assuntos
Acetil-CoA Carboxilase/biossíntese , Ácido Graxo Sintase Tipo I/biossíntese , Metástase Linfática/diagnóstico , Melanoma/diagnóstico , Neoplasias Cutâneas/diagnóstico , Acetil-CoA Carboxilase/análise , Biomarcadores Tumorais/análise , Diagnóstico Diferencial , Ácido Graxo Sintase Tipo I/análise , Humanos , Linfonodos/patologia , Metástase Linfática/patologia , Melanoma/enzimologia , Melanoma/patologia , Nevo Pigmentado/diagnóstico , Nevo Pigmentado/patologia , Biópsia de Linfonodo Sentinela , Neoplasias Cutâneas/enzimologia , Neoplasias Cutâneas/patologia , Melanoma Maligno Cutâneo
18.
Ann Diagn Pathol ; 31: 23-29, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29146054

RESUMO

BACKGROUND: Lymphocytic thrombophilic arteritis is a recently recognized subcuticular larger vessel vasculitis characterized by striking vascular luminal thrombosis. METHODS: The clinical features, histopathology and phenotypic profile of ten patients with lymphocytic thrombophilic arteritis were explored in an attempt to better define the entity from a clinical and pathophysiologic perspective. RESULTS: The patients were all female (mean age of 43) presenting with generally asymptomatic lower and upper extremity hyperpigmented macules. A consistent picture diagnostic of a connective tissue disease syndrome was not seen. The disease was not progressive although it was typically persistent. The morphology was characterized by a temporally heterogeneous subcutaneous arteritis targeting the endothelium and intima with changes ranging from incipient intimal expansion by hyaluronic acid to concentric intimal fibrin deposition to one of an end stage acellular intraluminal obliterative fibrous arteriopathy. The infiltrate was predominated by lymphocytes and histiocytes. The intimal elastic lamina was intact in most cases. All tested cases showed intimal and endothelial C5b-9 deposition, an upregulated type I interferon microenvironment and marked upregulation of the inducible interferon gamma 16 protein. CONCLUSIONS: Lymphocytic thrombophilic arteritis is a unique form of C5b-9 mediated arteritic endotheliopathy where the brunt of the changes involves the endothelium and intima and that is morphologically distinct from the transmural arteritis of benign cutaneous polyarteritis nodosa.


Assuntos
Arterite/patologia , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Interferon Tipo I/metabolismo , Tela Subcutânea/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Arterite/metabolismo , Feminino , Humanos , Inflamação/metabolismo , Inflamação/patologia , Linfócitos/patologia , Pessoa de Meia-Idade , Tela Subcutânea/metabolismo
19.
Am J Case Rep ; 18: 422-426, 2017 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-28420865

RESUMO

BACKGROUND The reciprocal translocation t(1;22)(p13;q13) involving the RBM15 and MKL1 genes is an uncommon abnormality that occurs in a subset of acute myeloid leukemia with megakaryocytic differentiation (AMKL). Variant translocations have been infrequently described in this subtype of leukemia. CASE REPORT We describe the case of a 3-month-old girl who presented with progressive abdominal distension, vomiting, and fever. Although there was no morphologic evidence of leukemia in the bone marrow, cytogenetic and metaphase fluorescence in situ hybridization analysis identified an insertion of p13p31 bands of chromosome 1 onto the long arm of chromosome 22, resulting in the karyotype: 46,XX,ins(22;1)(q13;p13p31). Subsequent liver biopsy demonstrated extensive involvement by AMKL. CONCLUSIONS AMKL can present with fewer than 20% blasts in the peripheral blood or bone marrow, necessitating careful evaluation for extramedullary disease. In other situations, bone marrow fibrosis can result in difficult marrow aspirations and a falsely decreased blast count. This case report highlights the critical role of careful cytogenetic and FISH testing in the diagnosis of AMKL.


Assuntos
Cromossomos Humanos Par 1 , Cromossomos Humanos Par 22 , Leucemia Megacarioblástica Aguda/genética , Translocação Genética , Feminino , Humanos , Lactente , Cariotipagem
20.
Transl Oncol ; 10(3): 442-449, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28448960

RESUMO

Distinguishing synchronous and metachronous primary lung adenocarcinomas from adenocarcinomas with intrapulmonary metastasis is essential for optimal patient management. In this study, multiple lung adenocarcinomas occurring in the same patient were evaluated using comprehensive histopathologic evaluation supplemented with molecular analysis. The cohort included 18 patients with a total of 52 lung adenocarcinomas. Eleven patients had a new diagnosis of multiple adenocarcinomas in the same lobe (n=5) or different lobe (n=6). Seven patients had a history of lung cancer and developed multiple new tumors. The final diagnosis was made in resection specimens (n=49), fine needle aspiration (n=2), and biopsy (n=1). Adenocarcinomas were non-mucinous, and histopathologic comparison of tumors was performed. All tumors save for one were subjected to ALK gene rearrangement testing and targeted Next Generation Sequencing (NGS). Using clinical, radiologic, and morphologic features, a confident conclusion favoring synchronous/metachronous or metastatic disease was made in 65% of patients. Cases that proved challenging included ones with more than three tumors showing overlapping growth patterns and lacking a predominant lepidic component. Genomic signatures unique to each tumor were helpful in determining the relationship of multiple carcinomas in 72% of patients. Collectively, morphologic and genomic data proved to be of greater value and achieved a conclusive diagnosis in 94% of patients. Assessment of the genomic profiles of multiple lung adenocarcinomas complements the histological findings, enabling a more comprehensive assessment of synchronous, metachronous, and metastatic lesions in most patients, thereby improving staging accuracy. Targeted NGS can identify genetic alterations with therapeutic implications.

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