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1.
Aging (Albany NY) ; 16(3): 1983-2004, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38301041

RESUMO

GV1001, which mimics the activity of human telomerase reverse transcriptase, protects neural cells from amyloid beta (Aß) toxicity and other stressors through extra-telomeric function, as noted in our prior in vitro studies. As per a recent phase II clinical trial, it improves cognitive function in patients with moderate to severe dementia. However, the underlying protective mechanisms remain unclear. This study aimed to investigate the effects of GV1001 on neurodegeneration, senescence, and survival in triple transgenic Alzheimer's disease (3xTg-AD) mice. GV1001 (1 mg/kg) was subcutaneously injected into old 3xTg-AD mice thrice a week until the endpoint for sacrifice, and survival was analysed. Magnetic resonance imaging (MRI) and Prussian blue staining (PBS) were performed to evaluate entry of GV1001 entrance into the brain. Diverse molecular studies were performed to investigate the effect of GV1001 on neurodegeneration and cellular senescence in AD model mice, with a particular focus on BACE, amyloid beta1-42 (Aß1-42), phosphorylated tau, volume of dentate gyrus, ß-galactosidase positive cells, telomere length, telomerase activity, and ageing-associated proteins. GV1001 crossed the blood-brain barrier, as confirmed by assessing the status of ferrocenecarboxylic acid-conjugated GV1001 using magnetic resonance imaging and PBS. GV1001 increased the survival of 3xTg-AD mice. It decreased BACE and Aß1-42 levels, neurodegeneration (i.e., reduced CA1, CA3 and dentate gyrus volume, decreased levels of senescence-associated ß-galactosidase positive cells, and increased telomere length and telomerase activity), and levels of ageing-associated proteins. We suggest that GV1001 exerts anti-ageing effects in 3xTg-AD mice by reducing neurodegeneration and senescence, which contributes to improved survival.


Assuntos
Doença de Alzheimer , Telomerase , Camundongos , Humanos , Animais , Peptídeos beta-Amiloides/metabolismo , Longevidade , Camundongos Transgênicos , Telomerase/metabolismo , Doença de Alzheimer/metabolismo , Envelhecimento , Modelos Animais de Doenças , beta-Galactosidase/metabolismo , Proteínas tau/metabolismo , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo
2.
Brain Behav Immun ; 115: 295-307, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37884161

RESUMO

GV1001 protects neural cells from amyloid-ß (Aß) toxicity and other stressors in in vitro studies and demonstrates clinically beneficial effects in patients with moderate to severe Alzheimer's disease (AD). Here, we investigated the protective effects and mechanism of action of GV1001 in triple transgenic AD (3xTg-AD) mice. We found that GV1001 improved memory and cognition in middle- and old-aged 3xTg-AD mice. Additionally, it reduced Aß oligomer and phospho-tau (Ser202 and Thr205) levels in the brain, and mitigated neuroinflammation by promoting a neuroprotective microglial and astrocyte phenotype while diminishing the neurotoxic ones. In vitro, GV1001 bound to gonadotropin releasing hormone receptors (GnRHRs) with high affinity. Levels of cyclic adenosine monophosphate, a direct downstream effector of activated GnRHRs, increased after GV1001 treatment. Furthermore, inhibition of GnRHRs blocked GV1001-induced effects. Thus, GV1001 might improve cognitive and memory functions of 3xTg-AD mice by suppressing neuroinflammation and reducing Aß oligomers levels and phospho-tau by activating GnRHRs and their downstream signaling pathways.


Assuntos
Doença de Alzheimer , Humanos , Camundongos , Animais , Pessoa de Meia-Idade , Idoso , Doença de Alzheimer/metabolismo , Camundongos Transgênicos , Receptores LHRH , Doenças Neuroinflamatórias , Proteínas tau/genética , Proteínas tau/metabolismo , Peptídeos beta-Amiloides/metabolismo , Hormônio Liberador de Gonadotropina , Modelos Animais de Doenças
3.
Pharmaceuticals (Basel) ; 16(1)2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36678619

RESUMO

L-ascorbic acid (Vit C) possesses a variety of dermatological functions in maintaining skin health and anti-aging properties. However, its topical application is challenging owing to its liability to light, oxygen, or heat. Therefore, in this study, a novel liposomal system, including a lipophilic neutral oil named a lipo-oil-some (LOS), was designed to improve the chemical stability and aid the skin absorption of Vit C. The vesicular systems were prepared using the ethanol injection method, employing phosphatidylcholine, cholesterol, dipalmitoyl-sn-glycerol-3-phosphoglycerol, and tricaprylin as neutral oil. The optimized LOS was characterized as follows: shape, multi-layered sphere; size, 981 nm; zeta potential, -58 mV; and Vit C encapsulation efficiency, 35%. The encapsulation of the labile compound into the novel system markedly enhanced photostability, providing over 10% higher Vit C remaining compared to Vit C solution or Vit C-loaded conventional liposome under a light intensity of 20,000 lx. On the other hand, the ex vivo skin permeation and accumulation of Vit C with the LOS system were comparable to those of smaller conventional liposomes (198 nm) in a Franz diffusion cell model mounted with porcine skin. Based on these findings, we concluded that the novel liposomal system could be utilized for skin delivery of Vit C with enhanced chemical stability.

5.
Medicine (Baltimore) ; 101(2): e28569, 2022 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-35029228

RESUMO

ABSTRACT: The purpose of our study was to differentiate arterial transit artifact from post-recanalization luxury perfusion on arterial spin labeling (ASL) image, and obtain the relationship between ASL signal intensity and clinical outcomes in patients with acute ischemic stroke.Thirty-five subjects with an acute middle cerebral artery (MCA) infarct were enrolled (18 with recanalized and 17 with non-recanalized MCAs). ASL images were obtained using pseudo-continuous ASL technique with 1600 ms (millisecond) of post-label delay within 3 days from symptom onset. Signal intensities on color ASL images were classified as high, intermediate, and poor grade visually. The ratio of maximum ASL signal between the ischemic area and contralateral side was calculated and compared between patients with and without MCA recanalization. Among patients with non-recanalized MCA, ASL signal ratios were compared between patients with and without hyperintense vessel sign on fluid attenuated inversion recovery (FLAIR). Also, correlation between the ASL signal ratio and National Institutes of Health Stroke Scale (NIHSS) score was evaluated.High or intermediate grade on color ASL images were more frequently found in patients with recanalized MCA (P < .01). Patients with non-recanalized MCA had higher ASL signal ratio in overall ASL signal grade (P = .010) and intermediate grade (P = .011). Among patients with non-recanalized MCA, those with hyperintense vessel sign on FLAIR had higher ASL signal ratios (P = .049). ASL signal ratio was negatively correlated with both initial (P = .023) and final (P = .003) NIHSS scores.The ASL signal ratio could help to differentiate between the pial collaterals and post-recanalization luxury perfusion. A higher ASL ratio was related with the hyperintense vessel sign on FLAIR and lower NIHSS score.


Assuntos
Isquemia Encefálica , Infarto da Artéria Cerebral Média , Acidente Vascular Cerebral , Circulação Cerebrovascular , Humanos , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Imageamento por Ressonância Magnética , Artéria Cerebral Média/diagnóstico por imagem , Marcadores de Spin
6.
PLoS One ; 16(8): e0255835, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34379652

RESUMO

The purposes of the study were to determine whether there are differences in texture analysis parameters between tonsil cancers and normal tonsils, and to correlate texture analysis with 18F-FDG PET/CT to investigate the relationship between texture analysis and metabolic parameters. Sixty-four patients with squamous cell carcinoma of the palatine tonsil were included. A ROI was drawn, including all slices, to involve the entire tumor. The contralateral normal tonsil was used for comparison with the tumors. Texture analysis parameters, mean, standard deviation (SD), entropy, mean positive pixels, skewness, and kurtosis were obtained using commercially available software. Parameters were compared between the tumor and the normal palatine tonsils. Comparisons were also performed among early tonsil cancer, advanced tonsil cancer, and normal tonsils. An ROC curve analysis was performed to assess discrimination of tumor from normal tonsils. Correlation between texture analysis and 18F-FDG PET/CT was performed. Compared to normal tonsils, the tumors showed a significantly lower mean, higher SD, higher entropy, lower skewness, and higher kurtosis on most filters (p<0.001). On comparisons among normal tonsils, early cancers, and advanced tonsil cancers, SD and entropy showed significantly higher values on all filters (p<0.001) between early cancers and normal tonsils. The AUC from the ROC analysis was 0.91, obtained from the entropy. A mild correlation was shown between texture parameters and metabolic parameters. The texture analysis parameters, especially entropy, showed significant differences in contrast-enhanced CT results between tumor and normal tonsils, and between early tonsil cancers and normal tonsils. Texture analysis can be useful as an adjunctive tool for the diagnosis of tonsil cancers.


Assuntos
Tonsila Palatina/diagnóstico por imagem , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias Tonsilares/diagnóstico , Idoso , Área Sob a Curva , Feminino , Fluordesoxiglucose F18/química , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Curva ROC , Compostos Radiofarmacêuticos/química , Sensibilidade e Especificidade , Neoplasias Tonsilares/patologia
7.
Int J Biol Macromol ; 183: 1732-1742, 2021 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-34051251

RESUMO

Oral montelukast (MTK) is prescribed to treat asthma or rhinitis, and is clinically investigated as new medication in the treatment of Alzheimer's dementia. Herein, in order to better patient's compliance, microsuspensions (MSs)-based oral liquid preparations of montelukast (MTK) were formulated with polymeric suspending agents including hypromellose (HPMC), and those drug-polymer interaction, physicochemical stability, dissolution, and in vivo pharmacokinetic profile was evaluated. When amorphous MTK particle was suspended in aqueous vehicle, it was readily converted into crystalline form and grown into aggregates, drastically lowering dissolution rate. However, the addition of HPMC polymer markedly suppressed the crystal growth, providing both improved drug stability and profound dissolution profile. Raman spectrometry denoted the inter-molecular hydrogen boding between MTK particle and HPMC polymer. The crystal growth or dissolution profile of MSs was markedly affected by pharmaceutical additives (sucrose or simethicone) in the preparations or storage temperature. The optimized HPMC-based MS exhibited over 80% higher bioavailability, compared to marketed granule (Singulair®) in rats. Therefore, novel MTK-loaded MS can be a promising liquid preparation, bettering oral absorption and patient's compliance.


Assuntos
Acetatos/administração & dosagem , Ciclopropanos/administração & dosagem , Derivados da Hipromelose/química , Quinolinas/administração & dosagem , Sulfetos/administração & dosagem , Acetatos/química , Acetatos/farmacocinética , Administração Oral , Animais , Cristalização , Ciclopropanos/química , Ciclopropanos/farmacocinética , Liberação Controlada de Fármacos , Estabilidade de Medicamentos , Ligação de Hidrogênio , Masculino , Quinolinas/química , Quinolinas/farmacocinética , Ratos , Solubilidade , Sulfetos/química , Sulfetos/farmacocinética , Suspensões
8.
Medicine (Baltimore) ; 100(21): e25823, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34032696

RESUMO

ABSTRACT: Sexual dysfunction is a common problem after cerebral infarction; however, little is known about sexual arousal in poststroke patients. Thus, this study aimed to investigate brain activation in response to visual sexual stimuli in patients with right middle cerebral artery (MCA) territory infarction using functional magnetic resonance imaging (fMRI). Using fMRI in 20 participants (11 right MCA infarction patients and 9 age-matched healthy controls), we assessed brain activation elicited by visual sexual stimuli (erotic images) and visual nonsexual stimuli (landscape images). In right MCA infarction patients, the left dorsolateral prefrontal cortex and the left frontal subgyral area were more strongly activated by visual sexual stimuli than by nonvisual sexual stimuli. Brain areas that were more activated by visual sexual stimuli in right MCA infarction patients than in controls included the right parahippocampal gyrus and the bilateral frontal subgyral area. These fMRI results suggest that brain activation patterns in response to visual sexual stimuli might be influenced by right MCA infarction. Further research is needed to explore the association between sexual dysfunction and brain activation in poststroke patients.


Assuntos
Encéfalo/fisiopatologia , Infarto da Artéria Cerebral Média/complicações , Comportamento Sexual/fisiologia , Disfunções Sexuais Fisiológicas/fisiopatologia , Percepção Visual/fisiologia , Adulto , Idoso , Encéfalo/irrigação sanguínea , Encéfalo/diagnóstico por imagem , Mapeamento Encefálico , Estudos de Casos e Controles , Literatura Erótica , Humanos , Infarto da Artéria Cerebral Média/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estimulação Luminosa/métodos , Disfunções Sexuais Fisiológicas/etiologia
9.
Molecules ; 26(6)2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33809569

RESUMO

The incorporation of permeation enhancers in topical preparations has been recognized as a simple and valuable approach to improve the penetration of antifungal agents into toenails. In this study, to improve the toenail delivery of efinaconazole (EFN), a triazole derivative for onychomycosis treatment, topical solutions containing different penetration enhancers were designed, and the permeation profiles were evaluated using bovine hoof models. In an in vitro permeation study in a Franz diffusion cell, hydroalcoholic solutions (HSs) containing lipophilic enhancers, particularly prepared with propylene glycol dicaprylocaprate (Labrafac PG), had 41% higher penetration than the HS base. Moreover, the combination of hydroxypropyl-ß-cyclodextrin with Labrafac PG further facilitated the penetration of EFN across the hoof membrane. In addition, this novel topical solution prepared with both lipophilic and hydrophilic enhancers was physicochemically stable, with no drug degradation under ambient conditions (25 °C, for 10 months). Therefore, this HS system can be a promising tool for enhancing the toenail permeability and therapeutic efficacy of EFN.


Assuntos
Portadores de Fármacos/química , Casco e Garras/efeitos dos fármacos , Casco e Garras/metabolismo , Permeabilidade/efeitos dos fármacos , Triazóis/administração & dosagem , Triazóis/química , Administração Tópica , Animais , Antifúngicos/administração & dosagem , Antifúngicos/química , Bovinos , Difusão , Sistemas de Liberação de Medicamentos/métodos , Onicomicose/tratamento farmacológico , Propilenoglicol/química
10.
PLoS One ; 15(1): e0227747, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31978097

RESUMO

We developed a visual ranking system by combining the parenchymal perfusion deficits (PPD) and hyperintense vessel signals (HVS) on arterial spin labeling (ASL) imaging. This study aimed to assess the performance of this ranking system by correlating with subtypes classified based on dynamic susceptibility contrast (DSC) imaging for evaluating the perfusion disturbance observed in patients with ischemic stroke. 32 patients with acute or subacute infarcts detected by DSC imaging were reviewed. Each patient's brain was divided into 12 areas. ASL ranks were defined by the presence (+) or absence (-) of PPD/HVS as follows; I:-/-, II:-/+, III: +/+, and IV: +/-. DSC imaging findings were categorized based on cerebral blood flow (CBF) and time to peak (TTP) as normal (normal CBF/TTP), mismatched (normal CBF/delayed TTP), and matched (decreased CBF/delayed TTP). Two reviewers rated perfusion abnormalities in the total of 384 areas. The four ASL ranks correlated well with the DSC subtypes (Spearman's r = 0.82). The performance of ASL ranking system was excellent as indicated by the area under the curve value of 0.94 using either matched or mismatched DSC subtype as the gold standard and 0.97 using only the matched DSC subtype as the gold standard. The two methods were in good-to-excellent agreement (maximum κ-values, 0.86). Inter-observer agreement was excellent (κ-value, 0.98). Although the number of patients was small and the number of dropouts was high, our proposed, ASL-based visual ranking system represented by PPD and HVS provides good, graded estimates of perfusion disturbance that agree well with those obtained by DSC perfusion imaging.


Assuntos
Infarto Encefálico/diagnóstico , Encéfalo/diagnóstico por imagem , Artérias Cerebrais/fisiopatologia , Angiografia por Ressonância Magnética/métodos , Imagem de Perfusão/métodos , Idoso , Idoso de 80 Anos ou mais , Encéfalo/irrigação sanguínea , Infarto Encefálico/fisiopatologia , Artérias Cerebrais/diagnóstico por imagem , Volume Sanguíneo Cerebral/fisiologia , Circulação Cerebrovascular/fisiologia , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Marcadores de Spin
11.
Taehan Yongsang Uihakhoe Chi ; 81(5): 1184-1193, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36238025

RESUMO

Purpose: This study was performed to evaluate the relationship between callosal microbleeds and anoxic brain injury. Materials and Methods: Twenty-seven patients with anoxic brain injuries were analyzed and retrospectively compared to the control group of patients without a history of anoxic brain injury using Fisher's exact test regarding comorbidities and cerebral microbleeds. The patient group was subdivided according to the presence of callosal microbleeds. Fisher's exact test was used to compare the presence of typical MRI findings of anoxic brain injury, use of cardiopulmonary resuscitation, and prognosis. The Mann-Whitney U test was used to compare the interval between the occurrence of anoxic brain injury to MRI acquisition. Results: The prevalence of cerebral microbleeds in the patient group was 29.6%, which was significantly higher than that in the control group at 3.7% (p = 0.012). All cerebral microbleeds in the patient group were in the corpus callosum. Compared with the callosal microbleed-absent group, the callosal microbleed-present group showed a tendency of good prognosis (6/8 vs. 11/19), fewer typical MRI findings of anoxic brain injury (2/8 vs. 10/19), and more cardiopulmonary resuscitation (6/8 vs. 12/19), although these differences did not reach statistical significance (p = 0.35, p = 0.19, and p = 0.45, respectively). Conclusion: Callosal microbleeds may be an adjunctive MRI marker for anoxic brain injury.

12.
Opt Express ; 27(10): 14695-14704, 2019 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-31163914

RESUMO

A terahertz continuous wave system is demonstrated for thickness measurement using Gouy phase shift interferometry without frequency sweep. One arm of the interferometer utilizes a collimated wave as a reference, and the other arm applies a focused beam for sample investigation. When the optical path difference (OPD) of the arms is zero, a destructive interference pattern is produced. Interference signal intensity changes induced by the OPD changes can be easily predicted by calculations. By minimizing the difference between the measured and the calculated signal against the OPD, the thicknesses of sub-100-µm-thick samples are determined at 625 GHz.

13.
Mol Neurobiol ; 56(11): 7617-7630, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31081524

RESUMO

Stem cell therapy is considered to be a promising future treatment for intractable neurological diseases, although all the clinical trials using stem cells have not yet shown any good results. Early passage mesenchymal stem cells (MSCs) have been used in most clinical trials because of the issues on safety and efficacy. However, it is not easy to get plenty of cells enough for the treatment and it costs too much. Lots of late passage MSCs can be obtained at lower cost but their efficacy would be a big hurdle for clinical trials. If late passage MSCs with better efficacy could be used in clinical trials, it could be a new and revolutionary solution to reduce cost and enhance easier clinical trials. In the present study, it was investigated whether late passage MSCs could be induced into glia-like cells (ghMSCs); ghMSCs had better efficacy and they protected neurons and the brain from ischemia, and insulin-like growth factor binding protein-4 (IGFBP-4) played a critical role in beneficial effect of ghMSCs. ghMSCs were induced from MSCs and treated in in vitro and in vivo models of ischemia. They effectively protected neurons from ischemia and restored the brain damaged by cerebral infarction. These beneficial effects were significantly blocked by IGFBP-4 antibody. The current study demontsrated that late passage hMSCs can be efficiently induced into ghMSCs with better neuroprotective effect on ischemic stroke. Moreover, the results indicate that IGFBP-4 released from ghMSCs may serve as one of the key neuronal survival factors secreted from ghMSCs.


Assuntos
Isquemia Encefálica/metabolismo , Proteína 4 de Ligação a Fator de Crescimento Semelhante à Insulina/metabolismo , Células-Tronco Mesenquimais/metabolismo , Neuroglia/metabolismo , Neuroproteção , Acidente Vascular Cerebral/metabolismo , Animais , Apoptose/efeitos dos fármacos , Células Cultivadas , Infarto Cerebral/patologia , Meios de Cultivo Condicionados/farmacologia , Ativação Enzimática , Glucose/deficiência , Humanos , Fator de Crescimento Insulin-Like I/metabolismo , Fator de Crescimento Insulin-Like II/metabolismo , Masculino , Modelos Biológicos , Neurônios/metabolismo , Oxigênio , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos Sprague-Dawley , Receptor IGF Tipo 1/metabolismo , Proteína X Associada a bcl-2/metabolismo
14.
Clin Otolaryngol ; 44(3): 336-342, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30729710

RESUMO

OBJECTIVE: The aim of this study was to investigate the clinical significance of 4-hour delayed-enhanced 3.0 Tesla (3T) 3D-fluid-attenuated inversion recovery (FLAIR) MR imaging in sudden sensorineural hearing loss (SSNHL). STUDY DESIGN: Case series with comparisons. SETTING: Tertiary referral centre. PARTICIPANTS: Eighty-seven idiopathic SSNHL patients were enrolled between January 2015 and December 2016 and received high dose steroid therapy and intratympanic steroid injections as salvage treatment. INTERVENTION: Pre-contrast, 10-minute and 4-hour delayed-enhanced 3D-FLAIR MR images were obtained using double-dose IV gadolinium. MAIN OUTCOME MEASURES: The results of treatment were evaluated according to Siegel's criteria 3 months after the start of treatment. Where possible lesion-side laterality of the inner ear was identified based on the MR images, the associations between MR findings and other clinical parameters were analysed, and the relationships between hearing recovery and MR image findings were assessed. RESULTS: Lesion-side laterality was identified on MRI in 52 (59.7%), 18 (20.1%) and 8 (9.2%) patients, based on 4-hour delayed, 10-minute delayed, and pre-contrast images, respectively. The hearing recovery rate was significantly lower in the patients with lesion-side laterality on 4-hour delayed images (P < 0.001). In a multivariate analysis, lesion-side laterality on 4-hour delayed images was associated with poor prognosis (OR = 5.6) after adjusting other prognostic factors including initial hearing level, lesion-side laterality on 10-min delayed images and presence of vertigo. In addition, as the extent of enhancement in the inner ear increased the probability of hearing recover decreased (P = 0.001). CONCLUSIONS: Contrast enhancement of inner ear structures can be seen on 4-hour delayed-enhanced 3T 3D-FLAIR MR images in idiopathic SSNHL. Asymmetric lesion-side enhancement of the inner ear may be associated with a poor prognosis.


Assuntos
Orelha Interna/patologia , Perda Auditiva Neurossensorial/diagnóstico , Perda Auditiva Súbita/diagnóstico , Audição/fisiologia , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Feminino , Seguimentos , Perda Auditiva Neurossensorial/fisiopatologia , Perda Auditiva Súbita/fisiopatologia , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Reprodutibilidade dos Testes , Fatores de Tempo
15.
Korean J Pediatr ; 62(4): 131-137, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30360041

RESUMO

PURPOSE: Respiratory syncytial virus (RSV) infection can cause various neurological complications. This study aimed to investigate the RSV-associated neurologic manifestations that present with seizures. METHODS: We retrospectively reviewed the medical records of patients aged less than 15 years with laboratory-confirmed RSV infections and seizures between January 2011 and December 2016 in a regional hospital in South Korea. RESULTS: During this period, 1,193 patients with laboratory-confirmed RSV infection were identified. Of these, 35 (35 of 1,193, 2.93%; boys, 19; girls, 16; mean age: 20.8±16.6 months) presented with seizures. Febrile seizure was the most common diagnosis (27 of 35, 77.1%); simple febrile seizure in 13 patients (13 of 27, 48.1%) and complex febrile seizure in 14 (14 of 27, 51.9%). Afebrile seizures without meningitis or encephalopathy were observed in 5 patients (5 of 35, 14.3%), seizures with meningitis in 2 (2 of 35, 5.7%), and seizure with encephalopathy in 1 (1 of 35, 2.9%) patient. Lower respiratory symptoms were not observed in 8 patients. In a patient with encephalopathy, brain diffusion-weighted magnetic resonance imaging revealed transient changes in white matter, suggesting cytotoxic edema as the mechanism underlying encephalopathy. Most patients recovered with general management, and progression to epilepsy was noted in only 1 patient. CONCLUSION: Although febrile seizure is the most common type of seizure associated with RSV infection, the proportion of patients with complex febrile seizure was higher than that of general febrile seizure. Transient cytotoxic edema may be a pathogenic mechanism in RSV-related encephalopathy with seizures.

16.
Neuroradiology ; 61(3): 265-274, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30415319

RESUMO

PURPOSE: White matter hyperintensities (WMH) and cerebral microbleeds (CMBs) are known to be associated with small vessel diseases (SVD) and neuroinflammation. The purpose was to investigate the relationship between CMBs and WMH in patients with systemic lupus erythematosus (SLE). METHODS: Thirty-one SLE patients with WMH and 27 SLE patients with normal brain MRI were compared. The presence, location, and grading of CMBs were assessed using susceptibility-weighted images. WMH volume was quantitatively measured. Clinical characteristics and serologic markers were compared. We also performed two separate subgroup analyses after (1) dividing WMH into inflammatory lesion vs. SVD subgroups and (2) dividing WMH into those with vs. without CMB subgroups. RESULTS: The WMH group showed more frequent CMBs than the normal MR group (p < 0.001). The WMH group showed higher SLE disease activity index, longer disease duration, and a higher incidence of antiphospholipid syndrome than the normal MR group (p = 0.02, 0.04, and 0.04, respectively). There was a moderate correlation between WMH volume and CMB grading (r = 0.49, p = 0.006). Within the WMH group, the inflammatory lesion subgroup showed more frequent CMBs and larger WMH volume than the SVD subgroup (p < 0.001 and 0.02, respectively). The WMH with CMB subgroup had larger WMH volume than the WMH without CMB subgroup (p = 0.004). CONCLUSION: In patients with SLE, CMBs could be related to large-volume WMH and inflammatory lesions. CMBs along with severe WMH could be used as an imaging biomarker of vasculitis in patients with SLE.


Assuntos
Hemorragia Cerebral/diagnóstico por imagem , Lúpus Eritematoso Sistêmico/diagnóstico por imagem , Substância Branca/diagnóstico por imagem , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Hemorragia Cerebral/patologia , Criança , Feminino , Humanos , Lúpus Eritematoso Sistêmico/patologia , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Substância Branca/patologia
17.
Nanotechnology ; 29(47): 47LT01, 2018 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-30211691

RESUMO

Rectifiers have been used to detect electromagnetic waves with very low photon energies. In these rectifying devices, different methods have been utilized, such as adjusting the bandgap and the doping profile, or utilizing the contact potential of the metal-semiconductor junction to produce current flow depending on the direction of the electric field. In this paper, it is shown that the asymmetric application of nano-electrodes to a metal-semiconductor-metal (MSM) structure can produce such rectification characteristics, and a terahertz (THz) wave detector based on the nano-MSM structure is proposed. Integrated with a receiving antenna, the fabricated device detects THz radiation up to a frequency of 1.5 THz with responsivity and noise equivalent power of 10.8 V/W and [Formula: see text] respectively, estimated at 0.3 THz. The unidirectional current flow is attributed to the thermionic emission of hot carriers accelerated by the locally enhanced THz field at the sharp end of the nano-electrode. This work not only demonstrates a new type of THz detector but also proposes a method for manipulating ultrafast charge-carrier dynamics through the field enhancement of the nano-electrode, which can be applied to ultrafast photonic and electronic devices.

18.
Laryngoscope ; 128(8): 1946-1951, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29330961

RESUMO

OBJECTIVE: To investigate the clinical significance of 4-hour delayed-enhanced 3.0 Tesla three-dimensional (3D) fluid-attenuated inversion recovery (FLAIR) magnetic resonance (MR) imaging in acute vestibular neuritis. STUDY DESIGN: A prospective observational study. METHODS: Twenty-nine vestibular neuritis patients were enrolled between January 2017 and June 2017. Vestibular function tests, comprising the caloric and video head impulse tests and vestibular-evoked myogenic potential measurements, were performed. Precontrast, 10-minute, and 4-hour delayed-enhanced 3D-FLAIR MR images using double-dose IV gadolinium were obtained. After laterality and extent of inner ear enhancement were defined, the patients were divided into groups based on the patterns of enhancement, and clinical parameters were analyzed according to the groups. RESULTS: Twenty patients (20 of 29, 69.0%) had obviously asymmetric enhancement of the affected inner ear structures on 4-hour delayed images, whereas only three patients (10.3%) had marked enhancement on 10-minute delayed images. The duration of spontaneous nystagmus (DurSN) was significantly longer in the patients with enhancement, especially with enhancement of the whole inner ear, including the vestibule and semicircular canals (P < 0.033). Spontaneous nystagmus resolved within 12 days in patients without laterality of enhancement, and within 16 days in ipsilesional enhancement confined to the inner auditory canal and fundus. Other results of vestibular function tests did not reveal any significant associations with MR enhancement. CONCLUSIONS: Contrast enhancement of the vestibular nerve and inner ear structures can be identified on 4-hour delayed-enhanced 3T 3D-FLAIR MR images in acute vestibular neuritis. The extent of inner ear enhancement may be associated with the DurSN. LEVEL OF EVIDENCE: 4. Laryngoscope, 1946-1951, 2018.


Assuntos
Imageamento Tridimensional , Imageamento por Ressonância Magnética/métodos , Neuronite Vestibular/diagnóstico por imagem , Doença Aguda , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Testes de Função Vestibular
19.
Biomaterials ; 155: 80-91, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29169040

RESUMO

In vivo tracking of transplanted stem cells has been a central aim of stem cell therapy. Although many tracking systems have been introduced, no method has yet been validated for clinical applications. We developed a novel sophisticated peptide (GV1001) that mimics hTERT (human telomerase reverse transcriptase) and analysed its ability to track and protect stem cells after transplantation. Ferrocenecarboxylic acid-conjugated GV1001 (Fe-GV1001) efficiently penetrated stem cells with no adverse effects. Moreover, Fe-GV1001 improved the viability, proliferation, and migration of stem cells under hypoxia. After Fe-GV1001-labelled stem cells were transplanted into the brains of rats after stroke, the labelled cells were easily tracked by MRI. Our findings indicate that Fe-GV1001 can be used for the in vivo tracking of stem cells after transplantation into the brain and can improve the efficacy of stem cell therapy by sustaining and enhancing stem cell characteristics under disease conditions.


Assuntos
Compostos Ferrosos/química , Fragmentos de Peptídeos/química , Telomerase/química , Animais , Humanos , Células-Tronco Mesenquimais/efeitos dos fármacos , Metalocenos , Células-Tronco Neurais/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Ratos , Transplante de Células-Tronco
20.
Int J Rheum Dis ; 21(3): 761-766, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27453474

RESUMO

We describe two cases of non-aneurysmal subarachnoid hemorrhage (SAH) and multifocal stenosis of the intracranial arteries. The patients' histories together with magnetic resonance angiography, vessel wall imaging and transcranial Doppler (TCD) indicated that the SAH was due to vasculitis or reversible cerebral vasoconstriction syndrome (RCVS). Differential diagnosis of vasculitis and RCVS is important because the treatment strategies are different: immunosuppressants in vasculitis and calcium channel blockers in RCVS. Vessel wall magnetic resonance imaging and TCD can be helpful in differentiating them.


Assuntos
Doenças Arteriais Cerebrais/etiologia , Artérias Cerebrais/fisiopatologia , Lúpus Eritematoso Sistêmico/complicações , Hemorragia Subaracnóidea/etiologia , Vasoconstrição , Adulto , Angiografia Cerebral/métodos , Doenças Arteriais Cerebrais/diagnóstico por imagem , Doenças Arteriais Cerebrais/tratamento farmacológico , Doenças Arteriais Cerebrais/fisiopatologia , Artérias Cerebrais/diagnóstico por imagem , Artérias Cerebrais/efeitos dos fármacos , Angiografia por Tomografia Computadorizada , Diagnóstico Diferencial , Feminino , Humanos , Imunossupressores/uso terapêutico , Lúpus Eritematoso Sistêmico/diagnóstico , Lúpus Eritematoso Sistêmico/tratamento farmacológico , Angiografia por Ressonância Magnética , Valor Preditivo dos Testes , Hemorragia Subaracnóidea/diagnóstico por imagem , Hemorragia Subaracnóidea/tratamento farmacológico , Hemorragia Subaracnóidea/fisiopatologia , Resultado do Tratamento , Vasoconstrição/efeitos dos fármacos , Vasodilatadores/uso terapêutico , Adulto Jovem
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