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1.
BMC Neurol ; 24(1): 200, 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38872109

RESUMO

BACKGROUND: In the United States, there are over seven million stroke survivors, with many facing gait impairments due to foot drop. This restricts their community ambulation and hinders functional independence, leading to several long-term health complications. Despite the best available physical therapy, gait function is incompletely recovered, and this occurs mainly during the acute phase post-stroke. Therapeutic options are limited currently. Novel therapies based on neurobiological principles have the potential to lead to long-term functional improvements. The Brain-Computer Interface (BCI) controlled Functional Electrical Stimulation (FES) system is one such strategy. It is based on Hebbian principles and has shown promise in early feasibility studies. The current study describes the BCI-FES clinical trial, which examines the safety and efficacy of this system, compared to conventional physical therapy (PT), to improve gait velocity for those with chronic gait impairment post-stroke. The trial also aims to find other secondary factors that may impact or accompany these improvements and establish the potential of Hebbian-based rehabilitation therapies. METHODS: This Phase II clinical trial is a two-arm, randomized, controlled, longitudinal study with 66 stroke participants in the chronic (> 6 months) stage of gait impairment. The participants undergo either BCI-FES paired with PT or dose-matched PT sessions (three times weekly for four weeks). The primary outcome is gait velocity (10-meter walk test), and secondary outcomes include gait endurance, range of motion, strength, sensation, quality of life, and neurophysiological biomarkers. These measures are acquired longitudinally. DISCUSSION: BCI-FES holds promise for gait velocity improvements in stroke patients. This clinical trial will evaluate the safety and efficacy of BCI-FES therapy when compared to dose-matched conventional therapy. The success of this trial will inform the potential utility of a Phase III efficacy trial. TRIAL REGISTRATION: The trial was registered as "BCI-FES Therapy for Stroke Rehabilitation" on February 19, 2020, at clinicaltrials.gov with the identifier NCT04279067.


Assuntos
Interfaces Cérebro-Computador , Terapia por Estimulação Elétrica , Transtornos Neurológicos da Marcha , Reabilitação do Acidente Vascular Cerebral , Humanos , Reabilitação do Acidente Vascular Cerebral/métodos , Terapia por Estimulação Elétrica/métodos , Transtornos Neurológicos da Marcha/reabilitação , Transtornos Neurológicos da Marcha/etiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/fisiopatologia , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Resultado do Tratamento , Método Simples-Cego , Marcha/fisiologia , Doença Crônica , Adulto
2.
Ann Biomed Eng ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38753110

RESUMO

This study aims to estimate the maximum power consumption that guarantees a thermally safe operation for a titanium-enclosed chest wall unit (CWU) subcutaneously implanted in the pre-pectoral area. This unit is a central piece of an envisioned fully-implantable bi-directional brain-computer interface (BD-BCI). To this end, we created a thermal simulation model using the finite element method implemented in COMSOL. We also performed a sensitivity analysis to ensure that our predictions were robust against the natural variation of physiological and environmental parameters. Based on this analysis, we predict that the CWU can consume between 378 and 538 mW of power without raising the surrounding tissue's temperature above the thermal safety threshold of 2  ∘ C. This power budget should be sufficient to power all of the CWU's basic functionalities, which include training the decoder, online decoding, wireless data transmission, and cortical stimulation. This power budget assessment provides an important specification for the design of a CWU-an integral part of a fully-implantable BD-BCI system.

3.
Phys Rev Lett ; 132(17): 171001, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38728703

RESUMO

Recently a dark matter-electron (DM-electron) paradigm has drawn much attention. Models beyond the standard halo model describing DM accelerated by high energy celestial bodies are under intense examination as well. In this Letter, a velocity components analysis (VCA) method dedicated to swift analysis of accelerated DM-electron interactions via semiconductor detectors is proposed and the first HPGe detector-based accelerated DM-electron analysis is realized. Utilizing the method, the first germanium based constraint on sub-GeV solar reflected DM-electron interaction is presented with the 205.4 kg·day dataset from the CDEX-10 experiment. In the heavy mediator scenario, our result excels in the mass range of 5-15 keV/c^{2}, achieving a 3 orders of magnitude improvement comparing with previous semiconductor experiments. In the light mediator scenario, the strongest laboratory constraint for DM lighter than 0.1 MeV/c^{2} is presented. The result proves the feasibility and demonstrates the vast potential of the VCA technique in future accelerated DM-electron analyses with semiconductor detectors.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38635379

RESUMO

This work presents a bi-directional brain-computer interface (BD-BCI) including a high-dynamic-range (HDR) two-step time-domain neural acquisition (TTNA) system and a high-voltage (HV) multipolar neural stimulation system incorporating dual-mode time-based charge balancing (DTCB) technique. The proposed TTNA includes four independent recording modules that can sense microvolt neural signals while tolerating large stimulation artifacts. In addition, it exhibits an integrated input-referred noise of 2.3 µVrms from 0.1- to 250-Hz and can handle a linear input-signal swing of up to 340 mVPP. The multipolar stimulator is composed of four standalone stimulators each with a maximum current of up to 14 mA (±20-V of voltage compliance) and 8-bit resolution. An inter-channel interference cancellation circuitry is introduced to preserve the accuracy and effectiveness of the DTCB method in the multipolar-stimulation configuration. Fabricated in an HV 180-nm CMOS technology, the BD-BCI chipset undergoes extensive in-vitro and in-vivo evaluations. The recording system achieves a measured SNDR, SFDR, and CMRR of 84.8 dB, 89.6 dB, and >105 dB, respectively. The measurement results verify that the stimulation system is capable of performing high-precision charge balancing with ±2 mV and ±7.5 mV accuracy in the interpulse-bounded time-based charge balancing (TCB) and artifactless TCB modes, respectively.

5.
Int J Surg ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38518079

RESUMO

BACKGROUND: The microscopic middle ear surgery involves a limited operating space and numerous important anatomical structures in which good visualization is crucial, as even a small amount of bleeding can greatly affect the clarity of surgical field. This study aims to investigate whether intravenous 1gram of tranexamic acid can improve surgical visualization and further shorten the operation time in microscopic middle ear surgery. METHODS: This study is a prospective, randomized, double-blind, controlled trial conducted from December 2021 to December 2022, enrolling patients who were scheduled for microscopic modified radical mastoidectomy due to chronic otitis media. In addition to standard techniques to optimize the surgical field, participants were randomized into the TXA (tranexamic acid) group (1gram diluted to 20 mL normal saline) and the control group (20 mL normal saline). The primary outcome was assessed based on the clarity of the surgical field using the Modena Bleeding Score. Secondary outcomes included operation time, the surgeon satisfaction with the visual clarity, postoperative 24-hour coagulation parameters, and the incidence of adverse events. Student's t test, Chi-square test and ANOVA of repeated measures were used for statistical analyses. RESULTS: A total of 28 patients were enrolled in each group using a 1:1 randomized allocation with similar demographic characteristics, including 24 male and 32 female individuals, and the mean age is 45.6±11.9 years. The surgical visualization in the TXA group was significantly better than that of the control group (2.29±0.46 vs. 2.89±0.31, P<0.001) as assessed by the Modena Bleeding Score. Furthermore, the TXA group demonstrated a shorter operation time compared to the control group (88.61±10.9 vs. 105.2±15.9, P<0.001) and higher surgeon satisfaction with surgical field (7.82±0.55 vs. 6.50±0.64, P<0.001). No statistically significant differences were found in postoperative coagulation parameters in the two groups. No TXA-related adverse events or complications occurred during the 12-month follow-up. CONCLUSION: Intravenous 1gram of TXA can further significantly improve the visual clarity in the microscopic middle ear surgery and shorten the operation time based on other standard measures implemented.

9.
Bio Protoc ; 13(23): e4892, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38094251

RESUMO

Human mitochondrial DNA (mtDNA) encodes several components of oxidative phosphorylation responsible for the bulk of cellular energy production. The mtDNA is transcribed by a dedicated human mitochondrial RNA polymerase (POLRMT) that is structurally distinct from its nuclear counterparts, instead closely resembling the single-subunit viral RNA polymerases (e.g., T7 RNA polymerase). The initiation of transcription by POLRMT is aided by two initiation factors: transcription factor A, mitochondrial (TFAM), and transcription factor B2, mitochondrial (TFB2M). Although many details of human mitochondrial transcription initiation have been elucidated with in vitro biochemical and structural studies, much remains to be addressed relating to the mechanism and regulation of transcription. Studies of such mechanisms require reliable, high-yield, and high-purity methods for protein production, and this protocol provides the level of detail and troubleshooting tips that are necessary for a novice to generate meaningful amounts of proteins for experimental work. The current protocol describes how to purify recombinant POLRMT, TFAM, and TFB2M from Escherichia coli using techniques such as affinity column chromatography (Ni2+ and heparin), how to remove the solubility tags with TEV protease and recover untagged proteins of interest, and how to overcome commonly encountered challenges in obtaining high yield of each protein. Key features • This protocol builds upon purification methods developed by Patel lab (Ramachandran et al., 2017) and others with greater detail than previously published works. • The protocol requires several days to complete as various steps are designed to be performed overnight. • The recombinantly purified proteins have been successfully used for in vitro transcription experiments, allowing for finer control of experimental components in a minimalistic system.

10.
Chronic Illn ; : 17423953231209377, 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-37960844

RESUMO

OBJECTIVES: While most individuals infected with COVID-19 recover completely within a few weeks, some continue to experience lingering symptoms. This study was conducted to identify and describe the clinical and subclinical manifestations of adult patients from the long-term effects of COVID-19. METHODS: The study analyzed 205 medical records of inpatients (age ≥ 16 years, ≥ 4 weeks post-COVID-19 recovery, and a negative SARS-CoV-2 status at enrollment) at Thong Nhat Hospital, Vietnam, from 6 September 2021 to 26 August 2022, using R language software. RESULTS: The majority of patients hospitalized with long COVID-19 symptoms (92.68%) had normal consciousness. The most common symptoms on admission were fatigue (59.02%), dyspnea (52.68%), and cough (42.93%). In total, 80% of patients observed respiratory symptoms, primarily dyspnea, while 42.44% reported neurological symptoms, with sleep disturbance being the most common. Noticeably, 42.93% of patients experienced respiratory failure in the post-COVID-19 period, resembling acute respiratory distress syndrome. DISCUSSION: These findings provide crucial insights into the epidemiology, clinical, and subclinical aspects of post-COVID-19 conditions, shedding light on the prevalence of common symptoms and the demographic distribution of affected patients. Understanding these manifestations is vital for patient well-being, improved clinical practice, and targeted healthcare planning, potentially leading to better patient care, management, and future interventions.

11.
Artigo em Inglês | MEDLINE | ID: mdl-37856256

RESUMO

The aim of this study is to estimate the maximum power consumption that guarantees the thermal safety of a skull unit (SU). The SU is part of a fully-implantable bi-directional brain computer-interface (BD-BCI) system that aims to restore walking and leg sensation to those with spinal cord injury (SCI). To estimate the SU power budget, we created a bio-heat model using the finite element method (FEM) implemented in COMSOL. To ensure that our predictions were robust against the natural variation of the model's parameters, we also performed a sensitivity analysis. Based on our simulations, we estimated that the SU can nominally consume up to 70 mW of power without raising the surrounding tissues' temperature above the thermal safety threshold of 1°C. When considering the natural variation of the model's parameters, we estimated that the power budget could range between 47 and 81 mW. This power budget should be sufficient to power the basic operations of the SU, including amplification, serialization and A/D conversion of the neural signals, as well as control of cortical stimulation. Determining the power budget is an important specification for the design of the SU and, in turn, the design of a fully-implantable BD-BCI system.


Assuntos
Interfaces Cérebro-Computador , Humanos , Temperatura Alta , Crânio , Cabeça , Próteses e Implantes
12.
J Neural Eng ; 20(5)2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37666246

RESUMO

Objective.Invasive brain-computer interfaces (BCIs) have shown promise in restoring motor function to those paralyzed by neurological injuries. These systems also have the ability to restore sensation via cortical electrostimulation. Cortical stimulation produces strong artifacts that can obscure neural signals or saturate recording amplifiers. While front-end hardware techniques can alleviate this problem, residual artifacts generally persist and must be suppressed by back-end methods.Approach.We have developed a technique based on pre-whitening and null projection (PWNP) and tested its ability to suppress stimulation artifacts in electroencephalogram (EEG), electrocorticogram (ECoG) and microelectrode array (MEA) signals from five human subjects.Main results.In EEG signals contaminated by narrow-band stimulation artifacts, the PWNP method achieved average artifact suppression between 32 and 34 dB, as measured by an increase in signal-to-interference ratio. In ECoG and MEA signals contaminated by broadband stimulation artifacts, our method suppressed artifacts by 78%-80% and 85%, respectively, as measured by a reduction in interference index. When compared to independent component analysis, which is considered the state-of-the-art technique for artifact suppression, our method achieved superior results, while being significantly easier to implement.Significance.PWNP can potentially act as an efficient method of artifact suppression to enable simultaneous stimulation and recording in bi-directional BCIs to biomimetically restore motor function.


Assuntos
Artefatos , Terapia por Estimulação Elétrica , Humanos , Eletrocorticografia , Eletroencefalografia , Amplificadores Eletrônicos
14.
J Wound Ostomy Continence Nurs ; 50(5): 375-380, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37467392

RESUMO

PURPOSE: The purpose of this study was to evaluate the Shieh Score's effectiveness in decreasing the rate of hospital-acquired pressure injuries when combined with an early warning notification system and standard order set of preventative measures. DESIGN: This was a prospective cohort study. SUBJECTS AND SETTING: This target population was nonpregnant, adult, hospitalized patients on inpatient and observation status at a tertiary hospital (Kaiser Permanente, Baldwin Park, California) during the 2020 year of the COVID-19 pandemic. METHODS: A new, risk assessment instrument, the Shieh Score, was developed in 2019 to predict hospitalized patients at high risk for pressure injuries. Data collection occurred between January 21, 2020, and December 31, 2020. When a hospital patient met the high-risk criteria for the Shieh Score, a provider-ordered pink-colored sheet of paper titled "Skin at Risk" was hung at the head of the bed and a standard order set of pressure injury preventative measures was implemented by nursing staff. RESULTS: Implementation of the program (Shieh Score, early warning system, and standard order set for preventive interventions) resulted in a 38% reduction in the annual hospital-acquired pressure injury rate from a mean incidence rate of 1.03 to 0.64 hospital-acquired pressure injuries per 1000 patient-days measured for the year 2020. CONCLUSION: The Shieh Score is a pressure injury risk assessment instrument, which effectively identifies patients at high risk for hospital-acquired pressure injuries and decreases the hospital-acquired pressure injury rate when combined with an early warning notification system and standard order set.


Assuntos
Úlcera por Pressão , Adulto , Humanos , Úlcera por Pressão/epidemiologia , Úlcera por Pressão/prevenção & controle , Úlcera por Pressão/etiologia , Estudos Prospectivos , Pandemias , Medição de Risco , Hospitais
16.
Artigo em Inglês | MEDLINE | ID: mdl-36821769

RESUMO

Objective: To better understand Takotsubo cardiomyopathy, a rare but life-threatening complication of acute substance withdrawal.Data Sources: A PubMed search was conducted to identify relevant case reports through 2021 using the medical subject headings alcohol withdrawal, opioid withdrawal, benzodiazepine withdrawal OR withdrawal AND Takotsubo OR stress cardiomyopathy.Study Selection: Case reports were included in the review if there was a diagnosis of Takotsubo cardiomyopathy in the setting of withdrawal from substances of abuse. Case reports were excluded if patients were withdrawing from other substances, actively intoxicated, or had myocardial ischemia.Data Extraction and Synthesis: Data were manually abstracted for the variables of interest, including demographics, symptoms, medical evaluation, and treatment. Descriptive statistics of the demographics, symptoms, medical evaluation, and treatment of Takotsubo cardiomyopathy were analyzed.Results: The mean (SD) age of patients experiencing withdrawal-associated Takotsubo cardiomyopathy was 50.8 years (15.2), and 64% of patients were female. The most common signs and symptoms were tachycardia (60%), changes in blood pressure (48%), altered mental status (48%), dyspnea (32%), nausea or vomiting (28%), and chest pain (28%). All patients with a reported electrocardiogram (92%) demonstrated ECG abnormalities; 76% had an elevated troponin level, and 24% had an elevated CK-MB level. Medications that could treat withdrawal and α2-agonists were utilized for 60% and 12% of patients, respectively. Ventilator support, cardiopulmonary resuscitation, and intra-aortic balloon pump were needed for 24%, 8%, and 8%, respectively, of patients with withdrawal-associated Takotsubo cardiomyopathy.Conclusions: Withdrawal-associated Takotsubo cardiomyopathy is a rare but potentially life-threatening complication of substance withdrawal. Clinicians should maintain a high degree of clinical suspicion for withdrawal-associated Takotsubo in patients with a history of substance use disorders or physical dependence on benzodiazepines or opioids, as the clinical presentation may be atypical.


Assuntos
Alcoolismo , Síndrome de Abstinência a Substâncias , Cardiomiopatia de Takotsubo , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Cardiomiopatia de Takotsubo/diagnóstico , Cardiomiopatia de Takotsubo/etiologia , Síndrome de Abstinência a Substâncias/complicações , Alcoolismo/complicações , Eletrocardiografia/efeitos adversos , Agonistas de Receptores Adrenérgicos alfa 2
18.
Acad Pediatr ; 23(6): 1247-1251, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36587733

RESUMO

OBJECTIVE: We longitudinally explored frequency of disordered eating among transgender and nonbinary (TGNB) adolescents and explored trends by gender identity and gender-affirming care. METHODS: Participants completed an abbreviated version of the Eating Disorder Examination Questionnaire (EDE-Q) at baseline, 3, 6, and 12 months after establishing care in a gender clinic. We analyzed descriptive statistics and multivariate linear regression analyses. RESULTS: Of the 91 TGNB adolescent participants, 61% were transmasculine, 30% transfeminine, and 7% nonbinary/gender-fluid. Among TGNB adolescents, disordered eating thoughts/behaviors were frequently endorsed with 26% of participants engaging in any occurrence of binge eating, 27% limiting the amount of food they ate, and 30% excluding foods from their diet. Forty percent of participants reported any occurrence of at least 1 disordered eating behavior and 17% at least 3 behaviors. Abbreviated EDE-Q responses did not differ significantly by sex assigned at birth, gender identity, gender-affirming medications, or time spent receiving gender-affirming care. There was a significant effect of age (P value = .003) on abbreviated EDE-Q scores. CONCLUSIONS: There were no significant changes in disordered eating after initiating gender-affirming medical care, possibly due to the limited study time frame of 12 months. Given the high prevalence of disordered eating behaviors, clinicians should consider screening all TGNB adolescents for disordered eating thoughts/behaviors throughout gender-affirming care. Future longitudinal research should recruit larger samples with a diverse range of gender identities and survey disordered eating thoughts/behaviors at least one year after starting gender-affirming medications.


Assuntos
Transtornos da Alimentação e da Ingestão de Alimentos , Pessoas Transgênero , Recém-Nascido , Humanos , Masculino , Adolescente , Feminino , Identidade de Gênero , Estudos Longitudinais , Transtornos da Alimentação e da Ingestão de Alimentos/epidemiologia , Inquéritos e Questionários
19.
Phys Rev Lett ; 129(22): 221301, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36493436

RESUMO

We present improved germanium-based constraints on sub-GeV dark matter via dark matter-electron (χ-e) scattering using the 205.4 kg·day dataset from the CDEX-10 experiment. Using a novel calculation technique, we attain predicted χ-e scattering spectra observable in high-purity germanium detectors. In the heavy mediator scenario, our results achieve 3 orders of magnitude of improvement for m_{χ} larger than 80 MeV/c^{2} compared to previous germanium-based χ-e results. We also present the most stringent χ-e cross-section limit to date among experiments using solid-state detectors for m_{χ} larger than 90 MeV/c^{2} with heavy mediators and m_{χ} larger than 100 MeV/c^{2} with electric dipole coupling. The result proves the feasibility and demonstrates the vast potential of a new χ-e detection method with high-purity germanium detectors in ultralow radioactive background.


Assuntos
Eletricidade , Elétrons
20.
Phys Rev Lett ; 129(22): 221802, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36493447

RESUMO

A search for exotic dark matter (DM) in the sub-GeV mass range has been conducted using 205 kg day data taken from a p-type point contact germanium detector of the CDEX-10 experiment at China's Jinping underground laboratory. New low-mass dark matter searching channels, neutral current fermionic DM absorption (χ+A→ν+A) and DM-nucleus 3→2 scattering (χ+χ+A→ϕ+A), have been analyzed with an energy threshold of 160 eVee. No significant signal was found; thus new limits on the DM-nucleon interaction cross section are set for both models at the sub-GeV DM mass region. A cross section limit for the fermionic DM absorption is set to be 2.5×10^{-46} cm^{2} (90% C.L.) at DM mass of 10 MeV/c^{2}. For the DM-nucleus 3→2 scattering scenario, limits are extended to DM mass of 5 and 14 MeV/c^{2} for the massless dark photon and bound DM final state, respectively.


Assuntos
Núcleo Celular , Fótons
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