Effect of a False Inertial Cue in the Velocity-Storage Circuit on Head Posture and Inertia Perception.

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.

Vestibular syncope.

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.

Heterogeneous Acrylic Resins with Bicontinuous Nanodomains as Low-Modulus Flexible Adhesives.

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.

The associations of adherence to the Mediterranean diet with chronic dizziness and imbalance in community-dwelling adults: KNHANES 2019-2021.

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.

Opsoclonus Induced by Head-Shaking in Vestibular Migraine.

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.

Effects of Baclofen on Central Paroxysmal Positional Downbeat Nystagmus.

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.

Disrupted Rotational Perception During Simultaneous Stimulation of Rotation and Inertia.

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.

Etiological distribution of isolated oculomotor nerve palsy: analysis of 633 patients and literature review.

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.

Ocular motor and vestibular dysfunction in central nervous system lymphoma.

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.

James Sharpe's Contributions to Neurology and Neuro-ophthalmology: A Posthumous Tribute 10 Years On.

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.

Association between body composition and subsequent cardiovascular diseases among 5-year breast cancer survivors.

BACKGROUND AND AIMS: Cardiovascular disease (CVD) remain one of the leading causes of mortality in breast cancer survivors. This study aimed to investigate the association between body composition and subsequent CVD in breast cancer survivors. METHODS AND RESULTS: A retrospective cohort study of more than 70 thousand 5-year breast cancer survivors aged 40 years or older was conducted using data from the National Health Insurance Service of South Korea. Based on the percentage of predicted lean body mass (pLBMP), appendicular skeletal muscle mass (pASMP), and body fat mass (pBFMP), which were calculated using prediction equations with anthropometric data and health habits, groups were equally divided into quartiles. The risk of CVD was evaluated using multivariate Cox proportional hazards regression. Compared to those with the lowest pLBMP and pASMP, those with the highest pLBMP and pASMP had a 38% and 42% lower risk of CVD, respectively. In contrast, those with the highest pBFMP had a 57% higher risk of CVD compared to those with the lowest pBFMP. Each 1 % increase in pLBMP and pASMP was associated with a decreased risk of CVD [pLBMP, adjusted hazard ratio (aHR): 0.96, 95% CI 0.94-0.98, p < 0.05; pASMP, aHR: 0.91, 95% CI 0.87-0.95, p < 0.05] while each 1 % increase in pBFMP was associated with the increased risk of CVD (aHR: 1.05, 95% CI 1.03-1.07, p < 0.01). CONCLUSION: In this cohort study, a high pLBMP, a high pASMP, and a low pBFMP were associated with a lower risk of CVD.

Association between antibiotic use and subsequent risk of prostate cancer: A retrospective cohort study in South Korea.

OBJECTIVES: Several studies suggest that antibiotic use may affect overall cancer incidence, but the association between antibiotics and prostate cancer is still unclear. This retrospective cohort study aimed to assess the association between antibiotics and the risk of prostate cancer. METHODS: A population-based retrospective cohort study was conducted using the Korean National Health Insurance Service (NHIS) database. 1 032 397 individuals were followed up from January 1, 2007, to December 31, 2019. Multivariable Cox hazards regression was utilized to calculate adjusted hazard ratios (aHRs) and 95% confidence intervals (CIs) for the risk of prostate cancer according to accumulative days of antibiotic use and the number of antibiotic classes used from 2002 to 2006. RESULTS: Individuals who used antibiotics for 180 or more days had a higher risk of prostate cancer (aHR, 1.46; 95% CI, 1.11-1.91) than those who did not use antibiotics. Also, individuals who used four or more kinds of antibiotics had a higher risk of prostate cancer (aHR, 1.18; 95% CI, 1.07-1.30) than antibiotic non-users. An overall trend was observed among participants who underwent health examinations. CONCLUSIONS: Our findings suggest that long-term use of antibiotics may affect prostate cancer incidence. Further studies are needed to improve understanding of the association between antibiotic use and prostate cancer incidence.

Scale for Ocular Motor Disorders in Ataxia (SODA) in Patients with Multiple System Atrophy.

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.

Ocular Motor Findings Aid in Differentiation of Spinocerebellar Ataxia Type 17 from Huntington's Disease.

Differentiation of spinocerebellar ataxia type 17 (SCA17) from Huntington's disease (HD) is often challenging since they share the clinical features of chorea, parkinsonism, and dystonia. The ocular motor findings remain to be elucidated in SCA17, and may help differentiating SCA17 from HD. We retrospectively compared the ocular motor findings of 11 patients with SCA17 with those of 10 patients with HD. In SCA17, abnormal ocular motor findings included impaired smooth pursuit (9/11, 82%), dysmetric saccades (9/11, 82%), central positional nystagmus (CPN, 7/11, 64%), abnormal head-impulse tests (4/11, 36%), and horizontal gaze-evoked nystagmus (GEN, 3/11, 27%). Among these, CPN was more frequently observed in SCA17 than in HD (7/11 (64%) vs. 0/10 (0%), p = 0.004) while saccadic slowing was more frequently observed in HD than in SCA17 (8/10 (80%) vs. 2/11 (18%), p = 0.009). Of six patients with follow-up evaluation, five later developed bilateral saccadic hypermetria (n = 4), GEN (n = 1), CPN (n = 1), bilaterally abnormal smooth pursuit (n = 1), and hyperactive head-impulse responses (n = 1) along with a clinical decline. Ocular motor abnormalities can be utilized as a diagnostic marker for differentiation of SCA17 from HD as well as a surrogate marker for clinical decline in SCA17.

Etiologic distribution of isolated abducens nerve palsy: Analysis of 807 patients and literature review.

BACKGROUND AND PURPOSE: The etiologies of abducens nerve palsy have shown a large variability among studies. This study aimed to establish the clinical features and underlying etiologies of isolated abducens nerve palsy by recruiting patients from all departments in a referral-based university hospital. METHODS: We reviewed the medical records of 807 patients with a confirmed diagnosis of isolated abducens nerve palsy at all departments of Seoul National University Bundang Hospital, Seongnam, Republic of Korea, from 2003 to 2020. We also compared the proportion of etiology with that of the patients pooled from the previous studies. RESULTS: The most common etiology was microvascular (n = 296, 36.7%), followed by idiopathic (n = 143, 17.7%), neoplastic (n = 115, 14.3%), vascular anomalies (n = 82, 10.2%), inflammatory (n = 76, 9.4%), and traumatic (n = 35, 4.3%). Patients were mostly managed by ophthalmologists (n = 576, 71.4%), followed by neurologists (n = 479, 59.4%), emergency physicians (n = 278, 34.4%), neurosurgeons (n = 191, 23.7%), and others (n = 72, 8.9%). The proportion of etiology significantly differed according to the age and sex of the patients and the specialties involved in the management (p < 0.001). Compared to the pooled data from the previous reports, the current study showed a higher prevalence of microvascular cause but a lower occurrence of traumatic and neoplastic causes. CONCLUSIONS: The results of previous studies on etiologic distribution of isolated abducens nerve palsy should be interpreted with consideration of the demographic features of patients recruited and the specialties involved.

Risk of future stroke in patients with a diagnosis of peripheral vertigo in the emergency department.

BACKGROUND AND PURPOSE: The temporal characteristics of stroke risks were evaluated in emergency department patients who had a diagnosis of peripheral vertigo. It was also attempted to reveal the stroke risk factor amongst those with peripheral vertigo. METHODS: This is a parallel-group cohort study in a tertiary referral hospital. After assigning each of 4367 matched patients to the comparative set of peripheral vertigo and appendicitis-ureterolithiasis groups and each of 4911 matched patients to the comparative set of peripheral vertigo and ischaemic stroke groups, the relative stroke risk was evaluated. In addition, to predict the individual stroke risk in patients with peripheral vertigo, any association between the demographic factors and stroke events was evaluated in the peripheral vertigo group. RESULTS: The peripheral vertigo group had a higher stroke risk than the appendicitis-ureterolithiasis group (hazard ratio 1.73, 95% confidence interval 1.18-2.55) but a lower risk than the ischaemic stroke group (hazard ratio 0.30, 95% confidence interval 0.24-0.37). The stroke risk of the peripheral vertigo group was just below that of small vessel stroke. The stroke risk of the peripheral vertigo group differed markedly by time: higher within 7 days, moderate between 7 days and 1 year, and diminished thereafter. Old age (>65 years), male gender and diabetes mellitus were the risk factors for stroke in the peripheral vertigo group. CONCLUSION: Patients with a diagnosis of peripheral vertigo in the emergency department showed a moderate future stroke risk and so a stroke preventive strategy tailored to the timing of symptom onset and individual risk is required.

Cultural and other beliefs as barriers to pediatric solid organ transplantation.

Organ shortage for transplantation is a global problem for both adult and pediatric recipients and this is particularly apparent in certain areas of the world and within specific communities. Cultural and religious beliefs can influence both a decision by a potential donor and/or their family to donate as well as a potential recipient's or their family's decision to accept the need for transplantation, agree to be listed and accept an organ. Globally, there are cultural and religious diversities that can present significant challenges for the transplant professional, particularly those whose practice is based in multicultural communities. In the pediatric population, in particular, barriers to organ transplantation related to culture and religion have not been well-described, with resulting implications for how they should or could be effectively addressed. Therefore, this review was undertaken to elucidate cultural and religious barriers to pediatric organ transplantation and, where feasible, to identify facilitators and strategies for overcoming these barriers.

Augmented ocular vestibular-evoked myogenic potentials in postural orthostatic tachycardia syndrome.

PURPOSE: To delineate the association between otolith function and changes in mean orthostatic blood pressure (BP) and heart rate (HR) in patients with postural orthostatic tachycardia syndrome (POTS). METHODS: Forty-nine patients with POTS were prospectively recruited. We analyzed the results of ocular vestibular-evoked myogenic potentials (oVEMPs) and cervical vestibular-evoked myogenic potentials (cVEMPs), as well as head-up tilt table tests using a Finometer. The oVEMP and cVEMP responses were obtained using tapping stimuli and 110 dB tone-burst sounds, respectively. We measured maximal changes in 5-s averaged systolic BP (SBP), diastolic BP (DBP), and heart rate (HR) within 15 s and during 10 min after tilting. We compared the results with those of 20 age- and sex-matched healthy participants. RESULTS: The n1-p1 amplitude of oVEMPs was larger in patients with POTS than in healthy participants (p = 0.001), whereas the n1 latency (p = 0.280) and interaural difference (p = 0.199) did not differ between the two. The n1-p1 amplitude was a positive predictor for POTS (odds ratio 1.07, 95% confidence interval 1.01-1.13, p = 0.025). Body weight (p = 0.007) and n1-p1 amplitude of oVEMP (p = 0.019) were positive predictors for ΔSBP15s in POTS, whereas aging was a negative predictor (p = 0.005). These findings were not observed in healthy participants. CONCLUSIONS: Augmented utricular inputs may be associated with a relative predominance of sympathetic over vagal control of BP and HR, especially for an early response during orthostasis in patients with POTS. Overt sympathoexcitation due to exaggerated utricular input and lack of readaptation may be associated with the pathomechanism of POTS.

Spatiotemporally controlled drug delivery via photothermally driven conformational change of self-integrated plasmonic hybrid nanogels.

BACKGROUND: Spatiotemporal regulation is one of the major considerations for developing a controlled and targeted drug delivery system to treat diseases efficiently. Light-responsive plasmonic nanostructures take advantage due to their tunable optical and photothermal properties by changing size, shape, and spatial arrangement. RESULTS: In this study, self-integrated plasmonic hybrid nanogels (PHNs) are developed for spatiotemporally controllable drug delivery through light-driven conformational change and photothermally-boosted endosomal escape. PHNs are easily synthesized through the simultaneous integration of gold nanoparticles (GNPs), thermo-responsive poly (N-isopropyl acrylamide), and linker molecules during polymerization. Wave-optic simulations reveal that the size of the PHNs and the density of the integrated GNPs are crucial factors in modulating photothermal conversion. Several linkers with varying molecular weights are inserted for the optimal PHNs, and the alginate-linked PHN (A-PHN) achieves more than twofold enhanced heat conversion compared with others. Since light-mediated conformational changes occur transiently, drug delivery is achieved in a spatiotemporally controlled manner. Furthermore, light-induced heat generation from cellular internalized A-PHNs enables pinpoint cytosolic delivery through the endosomal rupture. Finally, the deeper penetration for the enhanced delivery efficiency by A-PHNs is validated using multicellular spheroid. CONCLUSION: This study offers a strategy for synthesizing light-responsive nanocarriers and an in-depth understanding of light-modulated site-specific drug delivery.

Ultrasound-guided thread lifting for the prevention of parotid gland and diagnosing parotid duct complications.

BACKGROUND: Thread lifting is a common minimally invasive plastic surgery procedure. Parotid gland injury caused by thread lifting is a known complication; however, visual evidence of this complication is lacking. OBJECTIVES: This study aimed to present cases of parotid gland injury by thread lifting shown using ultrasound and to discuss the importance of ultrasound detection of the location of the parotid gland before thread insertion. METHODS: This study included eight patients diagnosed with parotid gland perforation and one with parotid duct injury due to threads from November 2020 to October 2022. RESULTS: Six patients showed tenderness and swelling, three were asymptomatic, and one with duct injury showed severe swelling and pain. Although the severity and duration of symptoms have differed, we confirmed the progress of improvement with conservative treatment and confirmed ultrasound findings progressed. CONCLUSIONS: Using ultrasound to detect the parotid gland's location before thread lifting might reduce the chance of parotid duct injury. Identifying immediate parotid duct or gland injury with ultrasound can help to act quickly for delayed pain or swelling and reduce the likelihood of additional complications.