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1.
Proc Natl Acad Sci U S A ; 121(18): e2320242121, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38657046

RESUMO

The brain's remarkable and efficient information processing capability is driving research into brain-inspired (neuromorphic) computing paradigms. Artificial aqueous ion channels are emerging as an exciting platform for neuromorphic computing, representing a departure from conventional solid-state devices by directly mimicking the brain's fluidic ion transport. Supported by a quantitative theoretical model, we present easy-to-fabricate tapered microchannels that embed a conducting network of fluidic nanochannels between a colloidal structure. Due to transient salt concentration polarization, our devices are volatile memristors (memory resistors) that are remarkably stable. The voltage-driven net salt flux and accumulation, that underpin the concentration polarization, surprisingly combine into a diffusionlike quadratic dependence of the memory retention time on the channel length, allowing channel design for a specific timescale. We implement our device as a synaptic element for neuromorphic reservoir computing. Individual channels distinguish various time series, that together represent (handwritten) numbers, for subsequent in silico classification with a simple readout function. Our results represent a significant step toward realizing the promise of fluidic ion channels as a platform to emulate the rich aqueous dynamics of the brain.

2.
Anal Chem ; 93(42): 14169-14177, 2021 10 26.
Artigo em Inglês | MEDLINE | ID: mdl-34644049

RESUMO

Diffusioosmosis (DO) results from ion transport near charged surfaces in the presence of electrolyte gradients and is critical in nanofluidic systems. However, DO has not yet been comprehensively studied because nanofabrication materials have limitations of low throughput and difficult quantification. Herein, we describe a self-assembled particle membrane (SAPM)-integrated microfluidic platform that can modulate the material properties (e.g., zeta-potential) and transport flux of nanopores. We quantify the effect of the zeta-potential on DO by measuring the electrical signals across three different nanopores/nanochannels of the SAPM. We then empirically quantify the effects of the temperature and ionic strength of the electrolytes on DO and reveal a nonlinear relationship with DO-driven ion transport; the ionic strengths govern the DO- or diffusion-effective ion transport phenomena. Finally, we demonstrate DO-driven electric power generation with enhanced performance as a potential application under optimized experimental conditions.


Assuntos
Nanoporos , Difusão , Eletrólitos , Transporte de Íons , Temperatura
3.
J Korean Med Sci ; 36(1): e5, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-33398942

RESUMO

BACKGROUND: To evaluate the patterns of distribution and clinical manifestations of ocular injuries referred to the level 1 trauma center of Pusan National University Hospital (PNUH) in Korea. METHODS: We analyzed 254 of 4,287 patients who were referred to the Department of Ophthalmology at the level 1 trauma center of the PNUH, from January 2016 through December 2018. Data on the incidence of ocular injuries, sex, age, monthly and seasonal distribution, day and time of injury, side of injury, cause, residence of patients, referral time to an ophthalmologist and subsequent examination time, final visual acuity (VA), and complications were obtained from medical records and retrospectively reviewed. The patients were grouped according to their main diagnosis using the Birmingham Eye Trauma Terminology System (BETTS) and Ocular Trauma Score (OTS). RESULTS: The incidence of ocular injuries with major trauma was higher in men (n = 207, 81.5%), the median age at time of injury was 54 years, and Pusan recorded the most cases. The incidences of ocular injury were 1.47/100,000, 1.57/100,000, 1.48/100,000 in 2016, 2017 and 2018, respectively. The most common cause was by a motorbike accident, followed by a pedestrian traffic accident and falls. According to the BETTS classification, open-globe injuries represented 4% of cases, closed-globe injuries represented 12.6%, and other injuries represented 83.1%. Open-globe injuries were significantly associated with low final VA (P = 0.01). In the OTS, 79.4% of patients received 4 or 5 points and 13.7% of patients received 1 or 2 points. The patients who received 1 or 2 points in the OTS score showed final VA below hand movement (P < 0.001), except for two patients. Lid laceration and low initial VA were highly correlated with poor final VA (P < 0.001). CONCLUSION: This is the first study on the epidemiology and clinical manifestations in trauma patients with ocular injuries at a level 1 trauma center. The incidences of ocular injuries with major trauma were about 1.47-1.57/100,000. BETTS, OTS, lid laceration and initial VA were associated with final VA. We expect our study to provide a basis of data for the evaluation, prevention, and management of ocular injuries in patients with systemic trauma.


Assuntos
Traumatismos Oculares/patologia , Índices de Gravidade do Trauma , Acidentes de Trânsito , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Traumatismos Oculares/epidemiologia , Feminino , Humanos , Incidência , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , República da Coreia/epidemiologia , Estudos Retrospectivos , Centros de Traumatologia , Acuidade Visual , Adulto Jovem
4.
Sensors (Basel) ; 20(17)2020 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-32899366

RESUMO

This paper presents an autonomous energy harvester based on a textile-based enzymatic biofuel cell, enabling an efficient power management and on-demand usage. The proposed biofuel cell works by an enzymatic reaction with glucose in sweat absorbed by the specially designed textile for sustainable and efficient energy harvesting. The output power of the textile-based biofuel cell has been optimized by changing electrode size and stacking electrodes and corresponding fluidic channels suitable for following power management circuit. The output power level of single electrode is estimated less than 0.5 µW and thus a two-staged power management circuit using intermediate supercapacitor has been presented. As a solution to produce a higher power level, multiple stacks of biofuel cell electrodes have been proposed and thus the textile-based biofuel cell employing serially connected 5 stacks produces a maximal power of 13 µW with an output voltage of 0.88 V when load resistance is 40 kΩ. A buck-boost converter employing a crystal oscillator directly triggered by DC output voltage of the biofuel cell makes it possible to obtain output voltage of the DC-DC converter is 6.75 V. The efficiency of the DC-DC converter is estimated as approximately 50% when the output power of the biofuel cell is tens microwatts. In addition, LT-spice modeling and simulation has been presented to estimate power consumption of each element of the proposed DC-DC converter circuit and the predicted output voltage has good agreement with measurement result.


Assuntos
Fontes de Energia Bioelétrica , Eletrodos , Têxteis , Simulação por Computador , Eletricidade
5.
Anal Chem ; 91(9): 6162-6171, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30931565

RESUMO

Various microfluidic devices have overcome many disadvantages common to conventional bioreactor systems by enabling active manipulation of cell-culture conditions, monitoring of cellular responses in high-throughput mode, and extraction of target cells in a relatively rapid and low-cost manner. However, existing microfluidic devices still have limitations, including the complexity of their operation and a lack of availability of dynamic control of the chemical environment. Here, we present a novel microfluidic bioreactor array device capable of not only the stable and dynamic programing of cell-culture environments but also the selective extraction of target cells. This device comprises 64 microchambers in a 16 × 4 array format, and each microchamber is integrated with a robust and nanoporous membrane on one side and an H-shaped entrance on the other. The membrane made of self-assembled particles allowed continuous and sequential delivery of various nutrients containing gene inducers to compartmentalized microbial cells, thereby enabling dynamic cell culturing. Additionally, the H-shaped entrance was used for local and selective blocking of the microchamber by employing UV-curable material, thereby enabling the retrieval of target cells from the device while sequestering nontarget cells in the microchambers. Our results demonstrated that the targeted rare cells could be isolated and separated from a mixture of cells by repeating the extraction procedure. Therefore, we anticipate that this microfluidic bioreactor array device will be widely used for not only screening/extraction but also off-chip postanalyses of various microorganisms.


Assuntos
Reatores Biológicos , Técnicas de Cultura de Células , Separação Celular , Escherichia coli/citologia , Técnicas Analíticas Microfluídicas , Técnicas de Cultura de Células/instrumentação , Separação Celular/instrumentação , Escherichia coli/isolamento & purificação , Técnicas Analíticas Microfluídicas/instrumentação , Tamanho da Partícula , Porosidade , Propriedades de Superfície
6.
Nanotechnology ; 28(7): 075103, 2017 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-28028248

RESUMO

We report a simple and versatile method for in vitro fabrication of scaffold-free tissue-engineered constructs with predetermined cellular alignment, by combining magnetic cell levitation with thermoresponsive nanofabricated substratum (TNFS) based cell sheet engineering technique. The TNFS based nanotopography provides contact guidance cues for regulation of cellular alignment and enables cell sheet transfer, while magnetic nanoparticles facilitate the magnetic levitation of the cell sheet. The temperature-mediated change in surface wettability of the thermoresponsive poly(N-isopropylacrylamide), substratum enables the spontaneous detachment of cell monolayers, which can then be easily manipulated through use of a ring or disk shaped magnet. Our developed platform could be readily applicable to production of tissue-engineered constructs containing complex physiological structures for the study of tissue structure-function relationships, drug screening, and regenerative medicine.


Assuntos
Técnicas de Cultura de Células/métodos , Campos Magnéticos , Nanopartículas de Magnetita/química , Mioblastos/citologia , Engenharia Tecidual/métodos , Acrilamidas/química , Animais , Linhagem Celular , Nanopartículas de Magnetita/ultraestrutura , Imãs , Camundongos , Mioblastos/fisiologia , Molhabilidade
7.
Med Sci Monit ; 23: 1401-1412, 2017 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-28325888

RESUMO

BACKGROUND Primary intraventricular hemorrhage (PIVH) is an uncommon type of intracerebral hemorrhage. Owing to its rarity, the clinical and radiological factors affecting outcomes in patients with PIVH have not been widely studied. MATERIAL AND METHODS We retrospectively reviewed 112 patients (mean age 53 years) treated for PIVH at our institution from January 2004 to December 2014. Clinical and radiological parameters were analyzed 3 months after initial presentation to identify factors associated with clinical outcomes, as assessed by the Glasgow Outcome Scale (favorable ≥4, unfavorable <4). RESULTS Of the 99 patients who underwent angiography, causative vascular abnormalities were found in 46%, and included Moyamoya disease, arteriovenous malformation, and cerebral aneurysm. At 3 months after initial presentation, 64% and 36% of patients were in the favorable and unfavorable outcome groups, respectively. The mortality rate was 19%. However, most survivors had no or mild deficits. Age, initial Glasgow Coma Scale (GCS) score, simplified acute physiology score (SAPS II), modified Graeb score, and various radiological parameters reflecting ventricular dilatation were significantly different between the groups. Specifically, a GCS score of less than 13 (p=0.015), a SAPS II score of less than 33 (p=0.039), and a dilated fourth ventricle (p=0.043) were demonstrated to be independent predictors of an unfavorable clinical outcome. CONCLUSIONS In this study we reveal independent predictors of poor outcome in primary intraventricular hemorrhage patients, and show that nearly half of the patients in our study had predisposing vascular abnormalities. Routine angiography is recommended in the evaluation of PIVH to identify potentially treatable etiologies, which may enhance long-term prognosis.


Assuntos
Hemorragia Cerebral/complicações , Adulto , Angiografia , Hemorragia Cerebral/diagnóstico por imagem , Feminino , Escala de Coma de Glasgow , Hemorragia , Humanos , Aneurisma Intracraniano/complicações , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
8.
Eur Spine J ; 26(8): 2021-2030, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28180980

RESUMO

PURPOSE: Majority of the previous studies compared lumbar spinal stenosis (LSS) and lumbar disc herniation (LDH) patients for analyses of LFH. However, the separation of normal/hypertrophied LF has often been ambiguous and the severity of hypertrophic activity differed. Here, we present a novel analysis scheme for LFH in which myofibroblast is proposed as a major etiological factor for LFH study. METHODS: Seventy-one LF patient tissue samples were used for this study. Initially, mRNA levels of the samples were assessed by qRT-PCR: angiopoietin-like protein-2 (ANGPTL2), transforming growth factor-beta1 (TGF-ß1), vascular endothelial growth factor (VEGF), interleukin-6, collagen-1, 3, 4, 5, and 11, and elastin. Myofibroblasts were detected by immune stain using α-smooth muscle actin (αSMA) as a marker. To study the myofibroblast in TGF-ß pathway, LF tissues were analyzed for protein levels of αSMA/TGF-ß1 by Western blot. In addition, from LF cells cultured with exogenous TGF-ß1 conditioned medium, expression of αSMA/collagen-1 was assessed and the cell morphology was identified. RESULTS: The comparative analysis of mRNA expression levels (LSS vs LDH) failed to show significant differences in TGF-ß1 (p = 0.08); however, we found a significant positive correlation among ANGPTL2, VEGF, TGF-ß1, and collagen-1 and 3, which represent common trends in hypertrophic activity (p < 0.05). We detected myofibroblast in the patient samples by αSMA staining, and the protein levels of αSMA were positively correlated with TGF-ß1. In LF cell culture, exogenous TGF-ß1 upregulated αSMA/collagen-1 mRNA levels and facilitated trans-differentiation to myofibroblast. CONCLUSIONS: We conclude that the transition of fibroblast to myofibroblasts via TGF-ß pathway is a key linker between inflammation and fibrosis in LFH mechanism.


Assuntos
Deslocamento do Disco Intervertebral/etiologia , Ligamento Amarelo/patologia , Vértebras Lombares , Miofibroblastos/patologia , Estenose Espinal/etiologia , Actinas , Idoso , Biomarcadores/metabolismo , Western Blotting , Feminino , Humanos , Hipertrofia/complicações , Hipertrofia/metabolismo , Hipertrofia/patologia , Deslocamento do Disco Intervertebral/metabolismo , Deslocamento do Disco Intervertebral/patologia , Ligamento Amarelo/metabolismo , Masculino , Pessoa de Meia-Idade , Miofibroblastos/metabolismo , Estudos Prospectivos , Estenose Espinal/metabolismo , Estenose Espinal/patologia
9.
Nano Lett ; 16(4): 2189-97, 2016 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-26990504

RESUMO

A high current ionic diode is achieved using an asymmetric nanochannel network membrane (NCNM) constructed by soft lithography and in situ self-assembly of nanoparticles with uniform surface charge. The asymmetric NCNM exhibits high rectified currents without losing a rectification ratio because of its ionic selectivity gradient and differentiated electrical conductance. Asymmetric ionic transport is analyzed with diode-like I-V curves and visualized via fluorescent dyes, which is closely correlated with ionic selectivity and ion distribution according to variation of NCNM geometries.

10.
Med Sci Monit ; 21: 2638-46, 2015 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-26343784

RESUMO

BACKGROUND: Intracerebral hemorrhage (ICH) is a well-known condition, but ICH restricted to the thalamus is less widely studied. We investigated the prognostic factors of thalamic ICHs. MATERIAL AND METHODS: Seventy patients from January 2009 to November 2014 were retrospectively reviewed. Patients who demonstrated spontaneous ICH primarily affecting the thalamus on initial brain computed tomography (CT) were enrolled. Patients were categorized into 2 groups based on their Glasgow Outcome Scale (GOS) scores. Various presumptive prognostic factors were analyzed to investigate relationships between various clinical characteristics and outcomes. RESULTS: Of the enrolled patients, 39 showed a GOS of 4-5, and were categorized as the good outcome group, while another 31 patients showed a GOS of 1-3 and were categorized as the poor outcome group. Initial GCS score, calculated volume of hematoma, presence of intraventricular hemorrhage (IVH), coexisting complications, hydrocephalus, performance of external ventricular drainage, and modified Graeb's scores of patients with IVH were significantly different between the 2 groups. In multivariate analysis, among the factors above, initial GCS score (P=0.002, Odds ratio [OR]=1.761, Confidence interval [CI]=1.223-2.536) and the existence of systemic complications (P=0.015, OR=0.059, CI=0.006-0.573) were independently associated with clinical outcomes. Calculated hematoma volume showed a borderline relationship with outcomes (P=0.079, OR=0.920, CI=0.839-1.010). CONCLUSIONS: Initial GCS score and the existence of systemic complications were strong predictive factors for prognosis of thalamic ICH. Calculated hematoma volume also had predictive value for clinical outcomes.


Assuntos
Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/terapia , Tálamo/patologia , Idoso , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Drenagem , Feminino , Escala de Resultado de Glasgow , Humanos , Hidrocefalia/diagnóstico , Hidrocefalia/terapia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Razão de Chances , Prognóstico , Estudos Retrospectivos , Índice de Gravidade de Doença , Tálamo/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Resultado do Tratamento
11.
Eur Spine J ; 24 Suppl 4: S600-5, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25632838

RESUMO

INTRODUCTION: Benign Metastasizing Leiomyoma (BML) is a rare disease that results from metastasis of uterine leiomyoma to distant sites with benign pathologic features. Spine BML is very rare so the information of its features and pathophysiology is seldom known. MATERIALS AND METHODS: We experienced a case of 42-year-old woman who presented with right buttock and leg pain with paresthesia. She had a surgical history of uterine myomectomy. Magnetic resonance imaging (MRI) of the lumbar spine revealed a well-circumscribed mass lesion in the posterior compartment of the L4 vertebral body, with extension into the ventral epidural space and both foramina. The mass showed hypointensity on T1-, T2-weighted images and strong homogeneous enhancement on gadolinium enhanced T1-weighted images. Tumor removal was conducted, and permanent biopsy revealed the mass as leiomyoma. Nine previous spine BML reports, which are known for all, were reviewed along with our case. We collated the clinical information and MRI findings of spine BML to figure out its common denominators. RESULTS: Premenopausal women, previous history of uterine myoma, myomectomy/hysterectomy, and lung BML seemed to be predisposing clinical factors. For the imaging findings, posterior vertebral body invasion with bony destruction, neural foramen invasion, and canal encroachment were shown as common denominators. Especially in MRI findings, low T1 and T2 signal intensities with strong homogeneous enhancement were their common features. CONCLUSION: We gathered the fragmentary information of the spine BML for the first time, especially the MRI findings. Although spine BML is rare, it surely exists. Accordingly, spine surgeons should be suspicious of spine BML given its typical clinical history and MRI findings.


Assuntos
Leiomiomatose/diagnóstico , Neoplasias da Coluna Vertebral/diagnóstico , Adulto , Feminino , Humanos , Leiomiomatose/cirurgia , Vértebras Lombares , Imageamento por Ressonância Magnética/métodos , Neoplasias da Coluna Vertebral/cirurgia , Neoplasias Uterinas/patologia , Neoplasias Uterinas/cirurgia
12.
Biomicrofluidics ; 18(1): 011503, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38370510

RESUMO

Green energy conversion in aqueous systems has attracted considerable interest owing to the sustainable clean energy demand resulting from population and economic growth and urbanization, as well as the significant potential energy from water resources and other regenerative sources coupled with fluids. In particular, molecular motion based on intrinsic micro/nanofluidic phenomena at the liquid-solid interface (LSI) is crucial for efficient and sustainable green energy conversion. The electrical double layer is the main factor affecting transport, interaction between molecules and surfaces, non-uniform ion distribution, synthesis, stimulated reactions, and motion by external renewable resources in both closed nanoconfinement and open surfaces. In this review, we summarize the state-of-the-art progress in physical and chemical reaction-based green energy conversion in LSI, including nanoscale fabrication, key mechanisms, applications, and limitations for practical implementation. The prospects for resolving critical challenges in this field and inspiring other promising research areas in the infancy stage (studying chemical and biological dynamics at the single-molecule level and nanofluidic neuromorphic computing) are also discussed.

13.
Am J Case Rep ; 25: e942753, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38282341

RESUMO

BACKGROUND Kimura disease is a rare, chronic inflammatory disorder typically presenting as a painless mass in the head or neck and associated with elevated serum immunoglobulin E and blood and tissue eosinophilia. Generally benign, its management is not well-defined, but corticosteroids are a common initial treatment. We detail a case of refractory Kimura disease successfully managed with CVP (Cyclophosphamide, Vincristine, Prednisone) chemotherapy and no recurrence during 6 rounds of treatment. CASE REPORT A 64-year-old woman, previously diagnosed with Kimura disease, returned to the hospital with upper eyelid ptosis. Upon examination, a solid mass was palpable in her left upper eyelid. Peripheral blood tests confirmed elevated IgE levels at 356.0 IU/ml. An excisional biopsy showed infiltration of lymphocytes and eosinophils, consistent with Kimura disease. Despite undergoing corticosteroid treatment, surgical debulking, radiation, and immunosuppressant therapy, her condition worsened. Concerns were raised due to imaging features suggestive of lymphoma, although no malignancy was evident in subsequent biopsies. It was decided to manage the disease using CVP chemotherapy, leading to significant symptom improvement. There have been no recurrences during the 12-month follow-up period. CONCLUSIONS Kimura disease is typically benign and responsive to treatment, but it often recurs and can progress. When symptoms are not controlled with conventional treatments, including corticosteroids, immunosuppressants, radiation, and surgical debulking, chemotherapy may be a reasonable option even when no definite signs of malignancy is identified. Further research is needed to explore the utility of CHOP and CVP in managing uncontrolled Kimura disease.


Assuntos
Hiperplasia Angiolinfoide com Eosinofilia , Doença de Kimura , Feminino , Humanos , Pessoa de Meia-Idade , Doença de Kimura/tratamento farmacológico , Hiperplasia Angiolinfoide com Eosinofilia/diagnóstico , Hiperplasia Angiolinfoide com Eosinofilia/tratamento farmacológico , Hiperplasia Angiolinfoide com Eosinofilia/patologia , Prednisona/uso terapêutico , Vincristina/uso terapêutico , Corticosteroides/uso terapêutico
14.
Int J Technol Assess Health Care ; 29(3): 244-53, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23769210

RESUMO

OBJECTIVES: The aim of this study was to systematically assess the long-term (≥ 6 months) benefits of epidural steroid injection therapies for patients with low back pain. METHODS: We identified randomized controlled trials by database searches up to October 2011 and by additional hand searches without language restrictions. Randomized controlled trials on the effects of epidurals for low back pain with follow-up for at least 6 months were included. Outcomes considered were pain relief, functional improvement in 6 to 12 months after epidural steroid injection treatment and the number of patients who underwent subsequent surgery. Meta-analysis was performed using a random-effects model. RESULTS: Twenty-nine articles were selected. The meta-analysis suggested that a significant treatment effect on pain was noted at 6 months of follow-up (weighted mean difference [WMD], -0.41; 95 percent confidence interval [CI], -0.66 to -0.16), but was no longer statistically significant after adjusting for the baseline pain score (WMD, -0.19; 95 percent CI, -0.61 to 0.24). Epidural steroid injection did not improve back-specific disability more than a placebo or other procedure. Epidural steroid injection did not significantly decrease the number of patients who underwent subsequent surgery compared with a placebo or other treatments (relative risk, 1.02; 95 percent CI, 0.83 to 1.24). CONCLUSIONS: A long-term benefit of epidural steroid injections for low back pain was not suggested at 6 months or longer. Introduction of selection bias in the majority of injection studies seems apparent. Baseline adjustment is essential when we evaluate pain as a main outcome of injection therapy.


Assuntos
Anestesia Epidural , Anti-Inflamatórios/administração & dosagem , Glucocorticoides/administração & dosagem , Humanos , Dor Lombar/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde , Radiculopatia
15.
J Cerebrovasc Endovasc Neurosurg ; 25(3): 245-252, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36851817

RESUMO

Carotid-cavernous fistulas, characterized by abnormal arteriovenous communication within the cavernous sinus (CS), can be classified as direct or indirect. Direct fistulas are defined as a direct connection between the internal carotid artery (ICA) and CS, whereas indirect fistulas result from an abnormal connection between the CS and dural arterial branches. The first-line treatment for both types of fistulas is endovascular intervention, most commonly accomplished through the transarterial and transvenous approaches of the conventional pathway, including the ICA, inferior and superior petrosal sinuses, or basilar plexus. Nonetheless, a retrograde approach through the superior ophthalmic vein may be necessary for individuals in whom conventional endovascular treatment fails. Herein, the current principles of surgical indication and technique are presented, along with case studies.

16.
Micromachines (Basel) ; 14(7)2023 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-37512622

RESUMO

Ion current rectification (ICR) is the ratio of ion current by forward bias to backward bias and is a critical indicator of diode performance. In previous studies, there have been many attempts to improve the performance of this ICR, but there is the intrinsic problem for geometric changes that induce ionic rectification due to fabrication problems. Additionally, the high ICR could be achieved in the narrow salt concentration range only. Here, we propose a multi-layered bipolar ionic diode based on an asymmetric nanochannel network membrane (NCNM), which is realized by soft lithography and self-assembly of homogenous-sized nanoparticles. Owing to the freely changeable geometry based on soft lithography, the ICR performance can be explored according to the variation of microchannel shape. The presented diode with multi-layered configuration shows strong ICR performance, and in a broad range of salt concentrations (0.1 mM~100 mM), steady ICR performance. It is interesting to note that when each anion-selective (AS) and cation-selective (CS) NCNM volume was similar to each optimized volume in a single-layered device, the maximum ICR was obtained. Multi-physics simulation, which reveals greater ionic concentration at the bipolar diode junction under forward bias and less depletion under backward in comparison to the single-layer scenario, supports this tendency as well. Additionally, under different frequencies and salt concentrations, a large-area hysteresis loop emerges, which indicates fascinating potential for electroosmotic pumps, memristors, biosensors, etc.

17.
Front Endocrinol (Lausanne) ; 14: 1079628, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36817584

RESUMO

Introduction: The primary treatment for active thyroid eye disease (TED) is immunosuppressive therapy with intravenous steroids. In this study, we attempted to predict responsiveness to steroid treatment in TED patients using eXtreme Gradient Boosting (XGBoost). Factors associated with steroid responsiveness were also statistically evaluated. Methods: Clinical characteristics and laboratory results of 89 patients with TED who received steroid treatment were retrospectively reviewed. XGBoost was used to explore responsiveness to steroid treatment, and the diagnostic performance was evaluated. Factors contributing to the model output were investigated using the SHapley Additive exPlanation (SHAP), and the treatment response was investigated statistically using SPSS software. Results: The eXtra Gradient Boost model showed high performance, with an excellent accuracy of 0.861. Thyroid-stimulating hormone, thyroid-stimulating immunoglobulin (TSI), and low-density lipoprotein (LDL) cholesterol had the highest impact on the model. Multivariate logistic regression analysis showed that less extraocular muscle limitation and high TSI levels were associated with a high risk of poor intravenous methylprednisolone treatment response. As a result of analysis through SHAP, TSH, TSI, and LDL had the highest impact on the XGBoost model. Conclusion: TSI, extraocular muscle limitation, and LDL cholesterol levels may be useful in predicting steroid treatment response in patients with TED. In terms of machine learning, XGBoost showed relatively robust and reliable results for small datasets. The machine-learning model can assist in decision-making for further treatment of patients with TED.


Assuntos
Oftalmopatia de Graves , Humanos , Oftalmopatia de Graves/tratamento farmacológico , Estudos Retrospectivos , Músculos Oculomotores , Imunoglobulinas Estimuladoras da Glândula Tireoide , Metilprednisolona/uso terapêutico
18.
ACS Appl Mater Interfaces ; 15(1): 2409-2418, 2023 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-36562122

RESUMO

Mass transport through nanopores occurs in various natural systems, including the human body. For example, ion transport across nerve cell membranes plays a significant role in neural signal transmission, which can be significantly affected by the electrolyte and temperature conditions. To better understand and control the underlying nanoscopic transport, it is necessary to develop multiphysical transport models as well as validate them using enhanced experimental methods for facile nanopore fabrication and precise nanoscale transport characterization. Here, we report a nanopore-integrated microfluidic platform to characterize ion transport in the presence of electrolyte and temperature gradients; we employ our previous self-assembled particle membrane (SAPM)-integrated microfluidic platform to produce various nanopores with different pore sizes. Subsequently, we quantify pore-size-dependent ionic transport by measuring the short circuit current (SCC) and open circuit voltage (OCV) across various nanopores by manipulating the electrolyte and temperature gradients. We establish three simple theoretical models that heavily depend on pore size, electrolyte concentration, and temperature and subsequently validate them with the experimental results. Finally, we anticipate that the results of this study would help clarify ion transport phenomena at low-temperature conditions, not only providing a fundamental understanding but also enabling practical applications of cryo-anesthesia in the near future.

19.
Front Endocrinol (Lausanne) ; 14: 1153312, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37223049

RESUMO

Design: Retrospective study. Purpose: The purpose of this retrospective study was to assess the changes in thyroid-stimulating hormone receptor (TSH-R) antibody levels following treatment in patients with moderate-to-severe and active Graves' orbitopathy (GO) and to investigate the correlation between these antibodies and treatment response. Methods: The subjects of this study comprised of patients newly diagnosed with moderate-to-severe and active GO within the age range of 19 to 79 years. All participants underwent intravenous methylprednisolone (IVMP) therapy for a duration of 12 weeks. Patients with a clinical activity score (CAS) decrease to or less than 3 and no symptom recurrence for at least 3months after the last dose of IVMP were classified as "Group 1". Those with a CAS equal to or greater than 4 were classified as "Group 2". TSH-R antibody levels were measured prior to and following IVMP treatment and treatment response was evaluated after the completion of IVMP therapy. All patients were monitored for a minimum of 6 months post-treatment, with ocular examinations and laboratory tests at the initial visit being included in the analysis. Results: The medical records of the 96 patients with GO were retrospectively reviewed. Seventy-five patients (78.1%) were response and 21 (21.9%) were non-responsive to IVMP treatment. A higher TSH-R antibody (TRAb) and thyroid-stimulating antibody (TSAb) following treatment were associated with a high risk of no treatment response (P = 0.017; P = 0.047, respectively). TRAb and TSAb levels before treatment were significantly related to TRAb and TSAb levels after treatment (P < 0.001, respectively). The cut-off values for the prediction of poor treatment response of the TRAb and TSAb before and after treatment were 8.305 IU/L, 5.035 IU/L and 449.5%, 361%, respectively (P = 0.027, P =0.001 and P = 0.136, P = 0.004, respectively). Conclusion: It was observed that elevated levels of TRAb and TSAb prior to IVMP treatment were positively correlated with post-treatment levels of these antibodies. Furthermore, in cases of non-response to IVMP therapy, a diminished decline in both antibodies was observed, and elevated levels of TRAb and TSAb post-treatment were found to be a significant predictor of poor treatment outcome. Measurement of TRAb and TSAb throughout the course of treatment in moderate-to-severe and active cases of GO may offer valuable insights into treatment prognosis and aid in the decision-making process regarding the potential need for increased IVMP dosage or alternative therapeutic strategies.


Assuntos
Oftalmopatia de Graves , Humanos , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Prognóstico , Oftalmopatia de Graves/diagnóstico , Oftalmopatia de Graves/tratamento farmacológico , Estudos Retrospectivos , Receptores da Tireotropina , Metilprednisolona/uso terapêutico , Tireotropina
20.
Neurosurgery ; 2023 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-37991350

RESUMO

BACKGROUND AND OBJECTIVES: Ossification of the posterior longitudinal ligament (OPLL) is a potentially catastrophic disease. Laminoplasty (LP) is a common surgical intervention, but postoperative kyphosis progression is a major complication, for which various risk factors have been identified and used in surgical decision-making. Our focus is on the ability of OPLL with specific morphological traits, designated as the true continuous segment (TCS), to stabilize alignment and prevent postoperative kyphosis after LP. METHODS: This retrospective case-control study included patients who underwent cervical LP for OPLL treatment with a minimum 1-year follow-up. Demographic, operative, and radiographic parameters were analyzed. TCS is defined as a continuous segment of OPLL that spans the disk space more than half of the adjacent vertebral body height without crack, or OPLL segment attached to both upper and lower adjacent vertebral bodies by bridging, or obvious interbody autofusion, and is identified from preoperative computed tomography. A subgroup analysis for preoperatively lordotic patients, divided into 2 groups based on cervical alignment at the final follow-up, was conducted to identify risk factors for kyphosis progression. Difference analysis, linear regression analysis for loss of lordosis (LoL), and logistic regression analysis for kyphosis progression were used. RESULTS: A total of 84 patients were identified. Among them, 78 patients with preoperatively lordotic alignment were divided into 2 groups: those who maintained lordotic alignment (n = 60) and those who progressed to kyphosis (n = 18). Regression analyses revealed a significant protective effect of TCS count against LoL and postoperative kyphosis, with a TCS count of 3 or more conclusively preventing kyphosis (sensitivity 1.000, specificity 0.283, area under the curve 0.629). CONCLUSION: For patients with OPLL, TCS was shown to protect against the LoL after LP. Therefore, TCS should be identified and considered when planning surgical treatment for OPLL.

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