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1.
Nature ; 631(8020): 378-385, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38961292

RESUMO

The execution of goal-oriented behaviours requires a spatially coherent alignment between sensory and motor maps. The current model for sensorimotor transformation in the superior colliculus relies on the topographic mapping of static spatial receptive fields onto movement endpoints1-6. Here, to experimentally assess the validity of this canonical static model of alignment, we dissected the visuo-motor network in the superior colliculus and performed in vivo intracellular and extracellular recordings across layers, in restrained and unrestrained conditions, to assess both the motor and the visual tuning of individual motor and premotor neurons. We found that collicular motor units have poorly defined visual static spatial receptive fields and respond instead to kinetic visual features, revealing the existence of a direct alignment in vectorial space between sensory and movement vectors, rather than between spatial receptive fields and movement endpoints as canonically hypothesized. We show that a neural network built according to these kinetic alignment principles is ideally placed to sustain ethological behaviours such as the rapid interception of moving and static targets. These findings reveal a novel dimension of the sensorimotor alignment process. By extending the alignment from the static to the kinetic domain this work provides a novel conceptual framework for understanding the nature of sensorimotor convergence and its relevance in guiding goal-directed behaviours.


Assuntos
Modelos Neurológicos , Movimento , Colículos Superiores , Percepção Visual , Animais , Feminino , Masculino , Objetivos , Cinética , Neurônios Motores/fisiologia , Movimento/fisiologia , Rede Nervosa/citologia , Rede Nervosa/fisiologia , Estimulação Luminosa , Desempenho Psicomotor/fisiologia , Reprodutibilidade dos Testes , Colículos Superiores/citologia , Colículos Superiores/fisiologia , Percepção Visual/fisiologia
2.
Nat Methods ; 20(12): 2058-2067, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37828153

RESUMO

Rapid advances in sequencing and analysis technologies have enabled the accurate detection of diverse forms of genomic variants represented as heterozygous, homozygous and mosaic mutations. However, the best practices for mosaic variant calling remain disorganized owing to the technical and conceptual difficulties faced in evaluation. Here we present our benchmark of 11 feasible mosaic variant detection approaches based on a systematically designed whole-exome-level reference standard that mimics mosaic samples, supported by 354,258 control positive mosaic single-nucleotide variants and insertion-deletion mutations and 33,111,725 control negatives. We identified not only the best practice for mosaic variant detection but also the condition-dependent strengths and weaknesses of the current methods. Furthermore, feature-level evaluation and their combinatorial usage across multiple algorithms direct the way for immediate to prolonged improvements in mosaic variant detection. Our results will guide researchers in selecting suitable calling algorithms and suggest future strategies for developers.


Assuntos
Benchmarking , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Software , Algoritmos , Mutação , Polimorfismo de Nucleotídeo Único
3.
Proc Natl Acad Sci U S A ; 120(37): e2308762120, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37669394

RESUMO

The medial prefrontal cortex (mPFC) and basolateral amygdala (BLA) are involved in the regulation of defensive behavior under threat, but their engagement in flexible behavior shifts remains unclear. Here, we report the oscillatory activities of mPFC-BLA circuit in reaction to a naturalistic threat, created by a predatory robot in mice. Specifically, we found dynamic frequency tuning among two different theta rhythms (~5 or ~10 Hz) was accompanied by agile changes of two different defensive behaviors (freeze-or-flight). By analyzing flight trajectories, we also found that high beta (~30 Hz) is engaged in the top-down process for goal-directed flights and accompanied by a reduction in fast gamma (60 to 120 Hz, peak near 70 Hz). The elevated beta nested the fast gamma activity by its phase more strongly. Our results suggest that the mPFC-BLA circuit has a potential role in oscillatory gear shifting allowing flexible information routing for behavior switches.


Assuntos
Tonsila do Cerebelo , Complexo Nuclear Basolateral da Amígdala , Animais , Camundongos , Córtex Pré-Frontal , Citoplasma , Raios gama
4.
Nature ; 570(7759): 117-121, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31068692

RESUMO

Aneuploidy, which refers to unbalanced chromosome numbers, represents a class of genetic variation that is associated with cancer, birth defects and eukaryotic micro-organisms1-4. Whereas it is known that each aneuploid chromosome stoichiometry can give rise to a distinct pattern of gene expression and phenotypic profile4,5, it remains a fundamental question as to whether there are common cellular defects that are associated with aneuploidy. Here we show the existence in budding yeast of a common aneuploidy gene-expression signature that is suggestive of hypo-osmotic stress, using a strategy that enables the observation of common transcriptome changes of aneuploidy by averaging out karyotype-specific dosage effects in aneuploid yeast-cell populations with random and diverse chromosome stoichiometry. Consistently, aneuploid yeast exhibited increased plasma-membrane stress that led to impaired endocytosis, and this defect was also observed in aneuploid human cells. Thermodynamic modelling showed that hypo-osmotic-like stress is a general outcome of the proteome imbalance that is caused by aneuploidy, and also predicted a relationship between ploidy and cell size that was observed in yeast and aneuploid cancer cells. A genome-wide screen uncovered a general dependency of aneuploid cells on a pathway of ubiquitin-mediated endocytic recycling of nutrient transporters. Loss of this pathway, coupled with the endocytic defect inherent to aneuploidy, leads to a marked alteration of intracellular nutrient homeostasis.


Assuntos
Aneuploidia , Pressão Osmótica , Proteoma/genética , Proteoma/metabolismo , Saccharomyces cerevisiae/citologia , Saccharomyces cerevisiae/genética , Estresse Fisiológico , Membrana Celular/metabolismo , Membrana Celular/patologia , Proteínas de Ligação a DNA/metabolismo , Endocitose , Complexos Endossomais de Distribuição Requeridos para Transporte/metabolismo , Homeostase , Humanos , Cariótipo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Termodinâmica , Fatores de Transcrição/metabolismo , Transcriptoma/genética , Ubiquitina/metabolismo , Complexos Ubiquitina-Proteína Ligase/metabolismo
5.
J Neurosci ; 43(9): 1530-1539, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36669887

RESUMO

The velocity-storage circuit participates in the vestibulopostural reflex, but its role in the postural reflex requires further elucidation. The velocity-storage circuit differentiates gravitoinertial information into gravitational and inertial cues using rotational cues. This implies that a false rotational cue can cause an erroneous estimation of gravity and inertial cues. We hypothesized the velocity-storage circuit is a common gateway for all vestibular reflex pathways and tested that hypothesis by measuring the postural and perceptual responses from a false inertial cue estimated in the velocity-storage circuit. Twenty healthy human participants (40.5 ± 8.2 years old, 6 men) underwent two different sessions of earth-vertical axis rotations at 120°/s for 60 s. During each session, the participants were rotated clockwise and then counterclockwise with two different starting head positions (head-down and head-up). During the first (control) session, the participants kept a steady head position at the end of rotation. During the second (test) session, the participants changed their head position at the end of rotation, from head-down to head-up or vice versa. The head position and inertial motion perception at the end of rotation were aligned with the inertia direction anticipated by the velocity-storage model. The participants showed a significant correlation between postural and perceptual responses. The velocity-storage circuit appears to be a shared neural integrator for the vestibulopostural reflex and vestibular perception. Because the postural responses depended on the inertial direction, the postural instability in vestibular disorders may be the consequence of the vestibulopostural reflex responding to centrally estimated false vestibular cues.SIGNIFICANCE STATEMENT The velocity-storage circuit appears to participate in the vestibulopostural reflex, which stabilizes the head and body position in space. However, it is still unclear whether the velocity-storage circuit for the postural reflex is in common with that involved in eye movement and perception. We evaluated the postural and perceptual responses to a false inertial cue estimated by the velocity-storage circuit. The postural and perceptual responses were consistent with the inertia direction predicted in the velocity-storage model and were correlated closely with each other. These results show that the velocity-storage circuit is a shared neural integrator for vestibular-driven responses and suggest that the vestibulopostural response to a false vestibular cue is the pathomechanism of postural instability clinically observed in vestibular disorders.


Assuntos
Sinais (Psicologia) , Percepção de Movimento , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Movimentos Oculares , Postura/fisiologia , Reflexo , Percepção de Movimento/fisiologia , Reflexo Vestíbulo-Ocular/fisiologia
6.
Curr Opin Neurol ; 37(1): 66-73, 2024 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-38193502

RESUMO

PURPOSE OF REVIEW: This review considers recent observations on vestibular syncope in terms of clinical features, laboratory findings, and potential mechanisms. RECENT FINDINGS: Vestibular syncope, potentially associated with severe fall-related injuries, may develop multiple times in about one-third of patients. Meniere's disease and benign paroxysmal positional vertigo are the most common causes of vestibular syncope, but the underlying disorders remain elusive in 62% of cases with vestibular syncope. The postictal orthostatic blood pressure test exhibits a lower diagnostic yield. Vestibular function tests, such as cervical vestibular-evoked myogenic potentials and video head impulse tests, can reveal one or more abnormal findings, suggesting compensated or ongoing minor vestibular dysfunctions. The pathomechanism of syncope is assumed to be the erroneous interaction between the vestibulo-sympathetic reflex and the baroreflex that have different operating mechanisms and action latencies. The central vestibular system, which estimates gravity orientation and inertia motion may also play an important role in abnormal vestibulo-sympathetic reflex. SUMMARY: Vestibular disorders elicit erroneous cardiovascular responses by providing false vestibular information. The results include vertigo-induced hypertension or hypotension, which can ultimately lead to syncope in susceptible patients.


Assuntos
Hipertensão , Vestíbulo do Labirinto , Humanos , Síncope/diagnóstico , Síncope/etiologia , Vertigem Posicional Paroxística Benigna
7.
Small ; 20(43): e2403497, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38924649

RESUMO

Adhesives play a critical role in the assembly of electronic devices, particularly as devices become more diverse in form factors. Flexible displays require highly transparent and rapidly recoverable adhesives with a certain stiffness. In this study, novel structured adhesives are developed that incorporate bicontinuous nanodomains to fabricate flexible adhesives with low moduli. This structure is obtained via polymerization-induced microphase separation using a macro chain transfer agent (CTA). Phase separation is characterized using small-angle X-ray scattering, transmission electron microscopy, and dynamic mechanical analysis. By optimizing the length of the macro CTA, an adhesive with both hard and soft nanodomains is produced, resulting in exceptional flexibility (strain recovery = 93%) and minimal modulus (maximum stress/applied strain = 7 kPa), which overperforms traditional adhesives. The optimized adhesive exhibits excellent resilience under extensive strain, as well as strong adhesion and transparency. Furthermore, dynamic folding tests demonstrate the exceptional stability of the adhesive under various temperature and humidity conditions, which is attributed to its unique structure. In summary, the distinct bicontinuous phase structure confers excellent transparency, flexibility, and reduced stiffness to the adhesive, rendering it well-suited for commercial foldable displays and suggesting potential applications in stretchable displays and wearable electronics.

8.
J Transl Med ; 22(1): 522, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38822335

RESUMO

BACKGROUND: Dizziness and vertigo rank among the top 10 reasons for emergency and clinical referrals to neurologists. Chronic dizziness and imbalance not only reduce quality of life, but also increase mortality. While the Mediterranean diet has long been considered beneficial for human and planetary health, its effects on chronic dizziness or imbalance are understudied. We investigated the associations of adherence to the Mediterranean diet with chronic dizziness and imbalance. METHODS: This study used data from the Korea National Health and Nutrition Examination Survey 2019-2021 and included 4,183 adults aged 40 years and older with complete information from diet, dizziness, and neurotology questionnaires. The alternate Mediterranean diet score (aMed) for nine food groups was calculated from 24-hour dietary recall data. Based on questionnaire responses, chronic dizziness was categorized as either isolated or chronic dizziness with imbalance, characterized by a cluster of difficulties maintaining a standing position, walking, or falling. RESULTS: In a multivariable-adjusted model, the prevalence of chronic imbalance was lower in the top aMed tertile than in the bottom tertile (OR 0.37; 95% CI, 0.18-0.74; p-trend = 0.01). Among the individual aMed components, the intake of whole grains and nuts exhibited an inverse relationship with chronic imbalance (OR 0.50; 95% CI, 0.27-0.93 for whole grains; OR 0.55; 95% CI, 0.31-1.01 for nuts). The aMed score was not associated with isolated chronic dizziness. CONCLUSIONS: Greater adherence to the Mediterranean diet may reduce chronic imbalance, particularly with an adequate intake of whole grains and nuts.


Assuntos
Dieta Mediterrânea , Tontura , Vida Independente , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Doença Crônica , Adulto , República da Coreia/epidemiologia , Idoso , Inquéritos Nutricionais , Equilíbrio Postural , Cooperação do Paciente , Inquéritos e Questionários
9.
Cerebellum ; 23(2): 856-860, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37227606

RESUMO

Opsoclonus refers to saccadic oscillations without an intersaccadic interval occurring in multiple planes. Opsoclonus mostly indicates dysfunction of the brainstem or cerebellum. We report opsoclonus induced by horizontal head-shaking without other signs of brainstem or cerebellar dysfunction in two patients with vestibular migraine (VM). The development of opsoclonus after horizontal head-shaking indicates unstable or hyperactive neural circuits between the excitatory and inhibitory saccadic premotor burst neurons in these patients with VM.


Assuntos
Transtornos de Enxaqueca , Transtornos da Motilidade Ocular , Humanos , Movimentos Sacádicos , Tronco Encefálico , Cerebelo , Vertigem
10.
Cerebellum ; 23(5): 1892-1898, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38498146

RESUMO

Paroxysmal positional nystagmus frequently occurs in lesions involving the cerebellum, and has been ascribed to disinhibition and enhanced canal signals during positioning due to cerebellar dysfunction. This study aims to elucidate the mechanism of central positional nystagmus (CPN) by determining the effects of baclofen on the intensity of paroxysmal positional downbeat nystagmus due to central lesions. Fifteen patients with paroxysmal downbeat CPN were subjected to manual straight head-hanging before administration of baclofen, while taking baclofen 30 mg per day for at least one week, and two weeks after discontinuation of baclofen. The maximum slow phase velocity (SPV) and time constant (TC) of the induced paroxysmal downbeat CPN were analyzed. The positional vertigo was evaluated using an 11-point numerical rating scale (0 to 10) in 9 patients. After treatment with baclofen, the median of the maximum SPV of paroxysmal downbeat CPN decreased from 30.1°/s [interquartile range (IQR) = 19.6-39.0°/s] to 15.2°/s (IQR = 11.2-22.0°/s, Wilcoxon signed rank test, p < 0.001) with the median decrement ratio at 40.2% (IQR = 28.2-50.6%). After discontinuation of baclofen, the maximum SPV re-increased to 24.6°/s (IQR = 13.1-34.4°/s, Wilcoxon signed rank test, p = 0.001) with the median increment ratio at 23.5% (IQR = 5.2-87.9%). In contrast, the TCs of paroxysmal downbeat CPN remained unchanged at approximately 3.0 s throughout the evaluation. The positional vertigo also decreased with the medication (Wilcoxon signed rank test, p = 0.020), and remained unchanged even after discontinuation of medication (Wilcoxon signed rank test, p = 0.737). The results of this study support the prior presumption that paroxysmal CPN is caused by enhanced responses of the semicircular canals during positioning due to cerebellar disinhibition. Baclofen may be tried in symptomatic patients with paroxysmal CPN.


Assuntos
Baclofeno , Nistagmo Patológico , Humanos , Baclofeno/uso terapêutico , Baclofeno/administração & dosagem , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Nistagmo Patológico/tratamento farmacológico , Nistagmo Patológico/fisiopatologia , Adulto , Relaxantes Musculares Centrais/uso terapêutico , Agonistas dos Receptores de GABA-B/uso terapêutico , Agonistas dos Receptores de GABA-B/farmacologia
11.
Cerebellum ; 23(4): 1369-1376, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38117451

RESUMO

A clinical scale fully dedicated to evaluating ocular motor abnormalities is required for now. We investigated the utility of a recently developed Scale for Ocular motor Disorders in Ataxia (SODA) in patients with multiple system atrophy (MSA). We prospectively assessed SODA in consecutive patients with MSA between August 2021 and August 2023 at the Korea University Medical Center. The results of the clinical exam-based SODA were compared with those measured using video-oculography (VOG-guided SODA). We also compared the findings with other established clinical scales targeting patients with MSA, including the Unified Multiple System Atrophy Rating Scale (UMSARS) I-II, Movement Disorder Society-Unified Parkinson's Disease Rating Scale motor part (UPDRS-III), Scale for Assessment of Rating of Ataxia (SARA), Composite Autonomic Symptom Score-31 (COMPASS-31), and Composite Autonomic Severity Score (CASS). Twenty patients were enrolled in our study (17 with cerebellar-type MSA and three with Parkinson-type MSA). Scores ranged from 1 to 14 (median [interquartile range (IQR)] = 8 [5-10]). Among the subscales, saccades had a median score of 2.5 (IQR = 1-3), followed by ocular pursuit (1 [0-1]), nystagmus (1 [0-2]), saccadic intrusions (1 [0-1]), vestibulo-ocular reflex (VOR) (0.5 [0-1]), ocular alignment (0 [0-1]), and VOR cancellation (1 [0-1]). The clinical-exam-based SODA (p = 0.020) and VOG-guided SODA (p = 0.034) positively correlated with disease duration. No correlation was found between clinical exam-based SODA and other scales. Skew deviation, gaze-evoked nystagmus, VOR cancellation, and smooth pursuit had the highest precision among the items. Ocular misalignment and spontaneous and positional nystagmus were frequently false positive and were poorly detected with clinical exam-based SODA. Six patients with repeated evaluation exhibited higher scores, along with deterioration documented on other clinical scales. The SODA can reliably predict neurodegeneration as an additional clinical surrogate in MSA.


Assuntos
Ataxia , Medições dos Movimentos Oculares , Atrofia de Múltiplos Sistemas , Transtornos da Motilidade Ocular , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Ataxia/complicações , Medições dos Movimentos Oculares/normas , Reações Falso-Positivas , Seguimentos , Atrofia de Múltiplos Sistemas/complicações , Nistagmo Fisiológico , Transtornos da Motilidade Ocular/complicações , Transtornos da Motilidade Ocular/diagnóstico , Transtornos da Motilidade Ocular/fisiopatologia , Acompanhamento Ocular Uniforme , Reflexo Vestíbulo-Ocular , Reprodutibilidade dos Testes , Movimentos Sacádicos , Sensibilidade e Especificidade
12.
Cerebellum ; 23(5): 2003-2011, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38702560

RESUMO

Two vestibular signals, rotational and inertial cues, converge for the perception of complex motion. However, how vestibular perception is built on neuronal behaviors and decision-making processes, especially during the simultaneous presentation of rotational and inertial cues, has yet to be elucidated in humans. In this study, we analyzed the perceptual responses of 20 participants after pairwise rotational experiments, comprised of four control and four test sessions. In both control and test sessions, participants underwent clockwise and counterclockwise rotations in head-down and head-up positions. The difference between the control and test sessions was the head re-orientation relative to gravity after rotations, thereby providing only rotational cues in the control sessions and both rotational and inertial cues in the test sessions. The accuracy of perceptual responses was calculated by comparing the direction of rotational and inertial cues acquired from participants with that predicted by the velocity-storage model. The results showed that the accuracy of rotational perception ranged from 80 to 95% in the four control sessions but significantly decreased to 35 to 75% in the four test sessions. The accuracy of inertial perception in the test sessions ranged from 50 to 70%. The accuracy of rotational perception improved with repetitive exposure to the simultaneous presentation of both rotational and inertial cues, while the accuracy of inertial perception remained steady. The results suggested a significant interaction between rotational and inertial perception and implied that vestibular perception acquired in patients with vestibular disorders are potentially inaccurate.


Assuntos
Percepção de Movimento , Vestíbulo do Labirinto , Humanos , Rotação , Masculino , Feminino , Percepção de Movimento/fisiologia , Adulto Jovem , Adulto , Vestíbulo do Labirinto/fisiologia , Sinais (Psicologia) , Movimentos da Cabeça/fisiologia , Orientação/fisiologia
13.
Eur J Neurol ; 31(6): e16261, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38411317

RESUMO

BACKGROUND AND PURPOSE: The etiological distribution of oculomotor nerve palsy has varied amongst the studies. This study aimed to define the clinical features and underlying etiologies of isolated oculomotor nerve palsy by recruiting patients from all departments in a referral-based university hospital. METHODS: The medical records of 672 patients who had a confirmed diagnosis of isolated oculomotor nerve palsy at all departments of Seoul National University Bundang Hospital, Seongnam, South Korea, from 2003 to 2020 were reviewed. A proportion of the etiology of isolated oculomotor nerve palsy was also compared with that of patients pooled from the previous studies that were searched on PubMed in May 2022. RESULTS: The most common etiology was microvascular (n = 168, 26.5%), followed by vascular anomalies (n = 110, 17.4%), neoplastic (n = 86, 13.6%), inflammatory (n = 79, 12.5%), idiopathic (n = 60, 9.5%) and traumatic (n = 53, 8.4%). Neurologists were mainly involved in the management of microvascular and inflammatory oculomotor nerve palsies whilst ophthalmologists mainly participated in the care of idiopathic, neoplastic and traumatic palsies. Neurosurgeons mostly took care of oculomotor nerve palsy due to vascular anomalies. CONCLUSIONS: The proportion of etiologies of isolated oculomotor nerve palsy may differ according to the specialties involved in the management. The results of previous studies on the etiological distribution of isolated oculomotor nerve palsy should be interpreted with this consideration.


Assuntos
Doenças do Nervo Oculomotor , Humanos , Doenças do Nervo Oculomotor/etiologia , Doenças do Nervo Oculomotor/epidemiologia , Pessoa de Meia-Idade , Adulto , Masculino , Feminino , Idoso , Adolescente , Adulto Jovem , Criança , Idoso de 80 Anos ou mais , Pré-Escolar , República da Coreia/epidemiologia
14.
Eur J Neurol ; 31(5): e16242, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38344918

RESUMO

BACKGROUND AND PURPOSE: Diagnosis of lymphoma involving the central nervous system (CNS) is challenging. This study aimed to explore the abnormal vestibular and ocular motor findings in CNS lymphoma. METHODS: A retrospective search of the medical records identified 30 patients with CNS lymphoma presenting ocular motor and vestibular abnormalities from four neurology clinics of university hospitals in South Korea (22 men, age range 14-81 years, mean 60.6 ± 15.2). The demographic and clinical features and the results of laboratory, radiological and pathological evaluation were analyzed. RESULTS: Patients presented with diplopia (13/30, 43%), vestibular symptoms (15/30, 50%) or both (2/30, 7%). In 15 patients with diplopia, abnormal ocular motor findings included ocular motor nerve palsy (n = 10, 67%), internuclear ophthalmoplegia (n = 2, 13%), external ophthalmoplegia (n = 2, 13%) and exophoria (n = 1, 7%). The vestibular abnormalities were isolated in 14 (82%) of 17 patients with vestibular symptoms and included combined unilateral peripheral and central vestibulopathy in three from lesions involving the vestibular nuclei. CNS lymphoma involved the brainstem (53%), cerebellum (33%), leptomeninges (30%), deep gray nuclei (23%) or cranial nerves (17%). Two patients showed the "double-panda" sign by involving the midbrain. CONCLUSIONS: This study expands the clinical and radiological spectra of CNS lymphoma. Neuro-ophthalmological and neuro-otological evaluation may guide the early diagnosis of CNS lymphoma.


Assuntos
Diplopia , Transtornos da Motilidade Ocular , Masculino , Humanos , Adolescente , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Estudos Retrospectivos , Transtornos da Motilidade Ocular/diagnóstico , Movimentos Oculares , Cerebelo , Paralisia
15.
Can J Neurol Sci ; 51(1): 117-121, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36710572

RESUMO

Dr. Sharpe was a leading eye movement researcher who had also been the editor of this journal. We wish to mark the 10th anniversary of his death by providing a sense of what he had achieved through some examples of his research.


Assuntos
Neurologia , Oftalmologia , Humanos , Masculino , Oftalmologia/história
16.
J Biomech Eng ; 146(11)2024 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-39037619

RESUMO

In orthopedic surgery, precise bone screw insertion is crucial for stabilizing fractures, necessitating a preliminary cortical bone drilling procedure. However, this process can induce temperatures exceeding 70 °C due to the low thermal conductivity of cortical bone, potentially leading to thermal osteonecrosis. Furthermore, significant cutting forces and torque pose risks of tool breakage and bone damage, underlining the need for high precision and optimal processing parameters. Traditionally, drilling relies on the surgeon's experience and often results in imprecise outcomes due to inconsistent feed rates. Therefore, this study proposes the use of a 6-axis robot for controlled drilling, offering precise control over angular velocities and consistent feed rates. Additionally, explore the use of cryogenic liquid nitrogen (LN2) as a novel cooling method compared to conventional saline solutions, examining its efficacy under various cutting conditions. The results demonstrate that LN2 cooling conditions lead to a reduction in thrust and torque under specific processing conditions, and facilitate smoother chip evacuation. Additionally, LN2 significantly lowers the peak temperature around the drilling site, thus minimizing the risk of thermal osteonecrosis. Consequently, the use of a 6-axis robot provides consistent feed rates, and LN2 cooling achieves optimal processing conditions, enabling a more controlled and effective drilling process.


Assuntos
Osso Cortical , Osso Cortical/cirurgia , Animais , Procedimentos Cirúrgicos Robóticos/instrumentação , Nitrogênio/química , Robótica/instrumentação , Temperatura Baixa , Fenômenos Mecânicos , Torque , Procedimentos Ortopédicos/instrumentação , Procedimentos Ortopédicos/métodos
17.
Neurocrit Care ; 40(2): 674-688, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37523110

RESUMO

BACKGROUND: Family caregivers of patients with severe acute brain injury (SABI) admitted to intensive care units (ICUs) with coma experience heightened emotional distress stemming from simultaneous stressors. Stress and coping frameworks can inform psychosocial intervention development by elucidating common challenges and ways of navigating such experiences but have yet to be employed with this population. The present study therefore sought to use a stress and coping framework to characterize the stressors and coping behaviors of family caregivers of patients with SABI hospitalized in ICUs and recovering after coma. METHODS: Our qualitative study recruited a convenience sample from 14 US neuroscience ICUs. Participants were family caregivers of patients who were admitted with ischemic stroke, intracerebral hemorrhage, subarachnoid hemorrhage, traumatic brain injury, or hypoxic-ischemic encephalopathy; had experienced a comatose state for > 24 h; and completed or were scheduled for tracheostomy and/or gastrostomy tube placement. Participants were recruited < 7 days after transfer out of the neuroscience ICU. We conducted live online video interviews from May 2021 to January 2022. One semistructured interview per participant was recorded and subsequently transcribed. Recruitment was stopped when thematic saturation was reached. We deductively derived two domains using a stress and coping framework to guide thematic analysis. Within each domain, we inductively derived themes to comprehensively characterize caregivers' experiences. RESULTS: We interviewed 30 caregivers. We identified 18 themes within the two theory-driven domains, including ten themes describing practical, social, and emotional stressors experienced by caregivers and eight themes describing the psychological and behavioral coping strategies that caregivers attempted to enact. Nearly all caregivers described using avoidance or distraction as an initial coping strategy to manage overwhelming emotions. Caregivers also expressed awareness of more adaptive strategies (e.g., cultivation of positive emotions, acceptance, self-education, and soliciting social and medical support) but had challenges employing them because of their heightened emotional distress. CONCLUSIONS: In response to substantial stressors, family caregivers of patients with SABI attempted to enact various psychological and behavioral coping strategies. They described avoidance and distraction as less helpful than other coping strategies but had difficulty engaging in alternative strategies because of their emotional distress. These findings can directly inform the development of additional resources to mitigate the long-term impact of acute psychological distress among this caregiver population.


Assuntos
Cuidadores , Capacidades de Enfrentamento , Humanos , Cuidadores/psicologia , Coma , Adaptação Psicológica , Unidades de Terapia Intensiva
18.
J Korean Med Sci ; 39(29): e214, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39079683

RESUMO

BACKGROUND: Dizziness/vertigo is one of the most common symptoms for which people seek healthcare. However, the healthcare expenditure attributable to dizziness/vertigo in South Korea remains poorly understood. We investigated the healthcare costs due to six major disorders causing dizziness/vertigo using claims data. METHODS: The healthcare costs were evaluated using all the claims data submitted to the Health Insurance Review and Assessment Service from January 1 to December 31, 2022. The six major vestibular disorders included for analysis were benign paroxysmal positional vertigo (BPPV), psychogenic/persistent postural perceptual dizziness (PPPD), vascular vertigo/dizziness (VVD), vestibular migraine (VM), Meniere's disease (MD), and vestibular neuritis (VN). RESULTS: During the 1-year study period, 4.1% of adults aged 20 or older visited hospitals due to dizziness/vertigo in South Korea. Compared to the general population, the patients with dizziness/vertigo were more often elderly, female, and residents of small towns. The total healthcare cost for the six major vestibular disorders was ₩547.8 billion (approximately $406.5 million). BPPV incurred the highest annual healthcare cost (₩183.5 billion, 33.5%), followed by VVD (₩158.8 billion, 29.0%), MD (₩82.2 billion, 15.0%), psychogenic/PPPD (₩60.3 billion, 11.0%), VN (₩32.9 billion, 6.0%), and VM (₩30.1 billion, 5.5%). The mean healthcare cost per hospital visit due to dizziness/vertigo was ₩96,524 (95% confidence interval, ₩96,194-₩96,855), 30% higher than the average (₩73,948) of the overall healthcare cost per hospital visit over the same period. CONCLUSION: Owing to higher healthcare costs for dizziness/vertigo and increased prevalence of dizziness/vertigo in the aged population, healthcare costs due to dizziness/vertigo will increase rapidly in South Korea. Thus, a guideline for cost-effective management of dizziness/vertigo should be established to reduce the healthcare costs due to these common symptoms.


Assuntos
Tontura , Custos de Cuidados de Saúde , Vertigem , Humanos , República da Coreia , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Idoso , Adulto Jovem , Vertigem Posicional Paroxística Benigna , Doença de Meniere/economia , Neuronite Vestibular , Transtornos de Enxaqueca/economia , Revisão da Utilização de Seguros
19.
J Clin Nurs ; 2024 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-38853351

RESUMO

AIM: To investigate the influence of self-management, self-efficacy, depression and social support by disease stage on quality of life in patients undergoing haemodialysis in South Korea. DESIGN: A cross-sectional survey design was used. Participants completed self-report questionnaires. METHODS: A convenience sample of 409 patients undergoing haemodialysis were recruited to complete self-report questionnaires. T-tests, ANOVA, multiple comparisons with Dunnett's T3 post hoc test, Pearson's correlation coefficients and hierarchical linear multiple regression were conducted using IBM SPSS version 25.0. RESULTS: The crisis stage group had the highest mean quality of life score (M = 83.92). Factors influencing quality of life were social support and depression in the crisis stage and depression, self-efficacy and self-management in the stable stage, explaining 38.5% and 51.5% of the total variation each. In the downward stage, only depression was a significant predictor of quality of life, explaining 55.9% of it. CONCLUSION: Long-term intervention to decrease depression regardless of disease stage to improve quality of life in haemodialysis patients is required. Nursing interventions should include increasing social support to promote patients' quality of life in the crisis stage and improving self-efficacy and self-management in the stable stage. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: Based on quality of life predictors, the development and implementation of patient-centered nursing interventions considering the patient's disease stage can improve haemodialysis patients' quality of life. IMPACT: There is minimal research on patients' quality of life considering disease stage. Depression was a significant factor of haemodialysis patients' quality of life in all stages, while social support was significant in the crisis stage and self-efficacy and self-management was significant in the stable stage. REPORTING METHOD: This study was reported according to the STROBE checklist. PATIENT OR PUBLIC CONTRIBUTION: Validated interviewer-administered questionnaires were completed by patients undergoing haemodialysis in this study.

20.
Opt Express ; 31(2): 2833-2845, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785288

RESUMO

Here, we unlock the properties of the recently introduced on-chip hollow-core microgap waveguide in the context of optofluidics which allows for intense light-water interaction over long lengths with fast response times. The nanoprinted waveguide operates by the anti-resonance effect in the visible and near-infrared domain and includes a hollow core with defined gaps every 176 µm. The spectroscopic capabilities are demonstrated by various absorption-related experiments, showing that the Beer-Lambert law can be applied without any modification. In addition to revealing key performance parameters, time-resolved experiments showed a decisive improvement in diffusion times resulting from the lateral access provided by the microgaps. Overall, the microgap waveguide represents a pathway for on-chip spectroscopy in aqueous environments.

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