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1.
Adv Sci (Weinh) ; 10(33): e2303308, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37867236

RESUMEN

Argyrodite-type Li6 PS5 Cl (LPSCl) has attracted much attention as a solid electrolyte for all-solid-state batteries (ASSBs) because of its high ionic conductivity and good mechanical flexibility. LPSCl, however, has challenges of translating research into practical applications, such as irreversible electrochemical degradation at the interface between LPSCl and cathode materials. Even for Li-ion batteries (LIBs), liquid electrolytes have the same issue as electrolyte decomposition due to interfacial instability. Nonetheless, current LIBs are successfully commercialized because functional electrolyte additives give rise to the formation of stable cathode-electrolyte interphase (CEI) and solid-electrolyte interphase (SEI) layers, leading to supplementing the interfacial stability between electrolyte and electrode. Herein, inspired by the role of electrolyte additives for LIBs, trimethylsilyl compounds are introduced as solid electrolyte additives for improving the interfacial stability between sulfide-based solid electrolytes and cathode materials. 2-(Trimethylsilyl)ethanethiol (TMS-SH), a solid electrolyte additive, is oxidatively decomposed during charge, forming a stable CEI layer. As a result, the CEI layer derived from TMS-SH suppresses the interfacial degradation between LPSCl and LiCoO2 , thereby leading to the excellent electrochemical performance of Li | LPSCl | LiCoO2 , such as superior cycle life over 2000 cycles (85.0% of capacity retention after 2000 cycles).

2.
Adv Mater ; 34(49): e2205498, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36268986

RESUMEN

Dynamic manipulation of supramolecular self-assembled structures is achieved irreversibly or under non-physiological conditions, thereby limiting their biomedical, environmental, and catalysis applicability. In this study, microgels composed of azobenzene derivatives stacked via π-cation and π-π interactions are developed that are electrostatically stabilized with Arg-Gly-Asp (RGD)-bearing anionic polymers. Lateral swelling of RGD-bearing microgels occurs via cis-azobenzene formation mediated by near-infrared-light-upconverted ultraviolet light, which disrupts intermolecular interactions on the visible-light-absorbing upconversion-nanoparticle-coated materials. Real-time imaging and molecular dynamics simulations demonstrate the deswelling of RGD-bearing microgels via visible-light-mediated trans-azobenzene formation. Near-infrared light can induce in situ swelling of RGD-bearing microgels to increase RGD availability and trigger release of loaded interleukin-4, which facilitates the adhesion structure assembly linked with pro-regenerative polarization of host macrophages. In contrast, visible light can induce deswelling of RGD-bearing microgels to decrease RGD availability that suppresses macrophage adhesion that yields pro-inflammatory polarization. These microgels exhibit high stability and non-toxicity. Versatile use of ligands and protein delivery can offer cytocompatible and photoswitchable manipulability of diverse host cells.


Asunto(s)
Microgeles , Macrófagos
3.
Micromachines (Basel) ; 12(4)2021 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-33918390

RESUMEN

The development of a compliant neural probe is necessary to achieve chronic implantation with minimal signal loss. Although fiber-based neural probes fabricated by the thermal drawing process have been proposed as a solution, their long-term effect on the brain has not been thoroughly investigated. Here, we examined the mechanical interaction of thermally drawn fiber implants with neural tissue through computational and histological analyses. Specifically, finite element analysis and immunohistochemistry were conducted to evaluate the biocompatibility of various fiber implants made with different base materials (steel, silica, polycarbonate, and hydrogel). Moreover, the effects of the coefficient of friction and geometric factors including aspect ratio and the shape of the cross-section on the strain were investigated with the finite element model. As a result, we observed that the fiber implants fabricated with extremely softer material such as hydrogel exhibited significantly lower strain distribution and elicited a reduced immune response. In addition, the implants with higher coefficient of friction (COF) and/or circular cross-sections showed a lower strain distribution and smaller critical volume. This work suggests the materials and design factors that need to be carefully considered to develop future fiber-based neural probes to minimize mechanical invasiveness.

4.
Neurosurgery ; 77(5): 709-17; discussion 717, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26197352

RESUMEN

BACKGROUND: Pulsatile tinnitus (PT) caused by venous sinus diverticulum is a relatively common, potentially incapacitating condition. Although treatment via an external approach or endovascular coiling has been reported, much remains unknown about the possible pathophysiological mechanisms and appropriate management of PT. OBJECTIVE: To review our case series of PT resulting from either sigmoid sinus diverticulum (SSD) or middle cranial fossa venous sinus diverticulum (MFD-VS) and to discuss the possible pathophysiological mechanisms and desirable treatment options. METHODS: Four PT patients with either SSD or MFD-VS were treated with transmastoid resurfacing. In 1 case, a revision operation was performed as a result of recurrence of PT 4.5 years after the initial operation. The medical records and temporal bone imaging findings were retrospectively reviewed. RESULTS: PT was resolved in all cases immediately after transmastoid resurfacing, but 1 patient in whom bone wax was used for initial resurfacing experienced PT 4.5 years later. The PT was successfully managed with revision resurfacing with autologous bone chips/bone cement. In the other cases, the resolution of PT lasted throughout a median follow-up of 5.75 years. Notably, 2 of 4 cases had preoperative low-frequency hearing loss (LFHL) and experienced immediate postoperative improvement in LFHL. CONCLUSION: PT resulting from either SSD or MFD-VS can be treated successfully with transmastoid resurfacing of the venous wall. Preoperative ipsilesional LFHL and the improvement of hearing threshold after surgical intervention may be preoperative and postoperative surrogate objective signatures of PT. To ensure the resolution of symptoms, secure reconstruction with firm materials and long-term follow-up are mandatory.


Asunto(s)
Senos Craneales/cirugía , Divertículo/cirugía , Procedimientos de Cirugía Plástica/métodos , Hueso Temporal/cirugía , Acúfeno/cirugía , Adulto , Anciano , Fosa Craneal Media/diagnóstico por imagen , Fosa Craneal Media/cirugía , Senos Craneales/diagnóstico por imagen , Divertículo/diagnóstico por imagen , Divertículo/epidemiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Radiografía , Estudios Retrospectivos , Hueso Temporal/diagnóstico por imagen , Acúfeno/diagnóstico por imagen , Acúfeno/epidemiología
5.
Korean J Audiol ; 18(2): 80-4, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25279230

RESUMEN

A speech discrimination test is a test using a list of 25 phonetically balanced monosyllables. It is often overlooked but significant enough for pure tone audiometry. Many physicians have performed pure tone audiometry but without a speech discrimination test. A 73-year-old woman visited our clinic complaining of sudden bilateral hearing loss. Pure tone audiometry showed only bilateral high frequency loss. However, speech discrimination had decreased markedly. We decided to follow-up after 1 week of Ginexin-F® (ginkgo leaf extract) and Nafril® (nafronyl oxalate). She felt a gait disturbance within 2 days. Magnetic resonance imaging revealed a left thalamic hemorrhage. After a 1 month hospitalization, the hematoma subsided, and speech discrimination recovered 3 months later. Acute hearing loss due to thalamic hemorrhage that recovered has never been reported. We report the first case of retrocochlear hearing loss that occurred with a thalamic hemorrhage in a patient who recovered.

6.
Drug Chem Toxicol ; 33(3): 291-301, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20429810

RESUMEN

This study was conducted to evaluate the potential reproductive toxicity of epichlorohydrin in a one-generation reproduction toxicity study in compliance with OECD Test Guideline 415. Twenty-four male and female rats per group were given epichlorohydrin by gavage at 0, 3.3, 10, and 30 mg/kg/day. Males were dosed for 10 weeks prior to and during mating. Females were dosed from 2 weeks before mating to day 21 of lactation. At 30 mg/kg, an increase in the incidence of clinical signs (i.e., nasal discharge, soft feces, depression, and piloerection), gross necropsy findings (i.e., cystic pustule of the epididymidis and enlargement of the kidney) and the weights of heart, liver, and epididymidis, a decrease in male fertility, and an increased incidence of histopathological changes of the testis, epididymidis, and kidney were observed. At 10 mg/kg, decreased male fertility and increased kidney weight and incidence of histopathological changes of the epididymidis were found. There was a slight, but nonsignificant, reduction in the male fertility index at the dose of 3.3 mg/ kg. Under these experimental conditions, the lowest-observed-adverse-effect level of epichlorohydrin was 3.3 mg/kg/day for parent animals and their offspring. The absolute toxic dose for parent animals and their offspring was estimated to be 10 mg/kg/day.


Asunto(s)
Epiclorhidrina/toxicidad , Reproducción/efectos de los fármacos , Animales , Animales Recién Nacidos , Conducta Animal , Peso Corporal , Exposición a Riesgos Ambientales , Epiclorhidrina/administración & dosificación , Femenino , Histocitoquímica , Masculino , Nivel sin Efectos Adversos Observados , Tamaño de los Órganos , Embarazo , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley
7.
Bull Environ Contam Toxicol ; 84(6): 667-71, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20431864

RESUMEN

This study investigated the effects of epichlorohydrin (ECH) on spermatogenesis and antioxidant system in rats. An increase in the incidence of clinical signs, gross pathology and histopathology findings in the epididymidis, and sperm abnormalities and a decrease in the testicular spermatid counts, epididymal sperm counts, and sperm motility were observed at 30 mg/kg/day. Oxidative stress in the epididymal tissue was detected at > or =3.3 mg/kg/day. The results show that graded doses of ECH elicit depletion of antioxidant defense system and that the adverse effects on male reproductive function in ECH-treated rats may be due to the induction of oxidative stress.


Asunto(s)
Contaminantes Ambientales/toxicidad , Epiclorhidrina/toxicidad , Epidídimo/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Animales , Antioxidantes/metabolismo , Epidídimo/enzimología , Epidídimo/metabolismo , Epidídimo/patología , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Peróxidos Lipídicos/metabolismo , Masculino , Ratas , Ratas Sprague-Dawley , Recuento de Espermatozoides , Motilidad Espermática/efectos de los fármacos , Espermatozoides/efectos de los fármacos , Espermatozoides/enzimología , Espermatozoides/metabolismo , Espermatozoides/patología , Pruebas de Toxicidad Crónica
8.
Toxicol Res ; 26(1): 67-74, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24278508

RESUMEN

The present study was conducted to obtain information on the effects of amitraz on reproductive and developmental parameters in rats. The test chemical was administered via the drinking water containing 0, 40, 120, and 360 ppm to male rats from 2 weeks before mating to the end of 14-day mating period and to females from 2 weeks before mating, throughout mating, gestation and up to lactational day 4. During the study period, clinical signs, body weights, food intake, organ weights, reproductive and littering findings, necropsy findings, sperm parameters, and histopathology were examined. At 360 ppm, decreases in the body weight gain, food consumption, and the number of live pups and an increase in the post-implantation loss were observed. In addition, decreases in the seminal vesicle weight and sperm motility were found in males. At 120 ppm, a decrease in the food consumption was found transiently in both males and females, but no reproductive and developmental toxicity was observed in both sexes. There were no signs of either general or reproductive and developmental toxicity in the 40 ppm group. Based on these results, it was concluded that the repeated oral administration of amitraz to rats resulted in a decrease in the food consumption at 120 ppm and decreases in the seminal vesicle weight, sperm motility, and the number of live pups and an increase in the post-implantation loss at 360 ppm in rats. Under these experimental conditions, the no-observed-adverse-effect level (NOAEL) of amitraz for general and reproduction/developmental toxicity was believed to be 120 ppm, and the no-observed-effect level (NOEL) of amitraz was believed to be 40 ppm in rats.

9.
Toxicol Res ; 25(4): 203-207, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32038839

RESUMEN

Present study was conducted to investigate potential effects of epichlorohydrin on testicular and epididymal function in male rats. The test chemical was administered to adult male rats by gavage at dose levels of 0, 3.125, 12.5, and 50 mg/kg/day for 7 days. Testicular and epididymal function were assessed by measurement of reproductive organ weight, testicular spermatid count, epididymal sperm count, motility and morphology, and histopathology in rats. At 50 mg/kg, a decrease in the sperm motility and an increase in the incidence of sperm abnormalities were observed. Histopatho-logical examinations revealed an increase in the incidence of histopathological changes including cell debris in the ducts, vacuolization of the epithelial cells, oligospermia, and epithelial disruption in the proximal caput epididymidis. At 12.5 mg/kg, an increase in the incidence of histopathological changes of the epididymidis was found. There were no treatment-related effects at 3.125 mg/kg. These results show that 7-day repeated oral administration of epichlorohydrin to male rats results in adverse effects on sperm motility, sperm morphology, and epididymal histology at ≥ 12.5 mg/kg/day.

10.
Toxicol Res ; 24(4): 263-271, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32038804

RESUMEN

Recently we reported that 2-bromopropane (2-BP) has maternal toxicity, embryotoxicity, and teratogenicity in Sprague-Dawley rats. The aims of this study are to examine the potential effects of 2-BP administration on pregnant dams and embryo-fetal development, and to investigate the effects of metabolic activation induced by phenobarbital (PB) on developmental toxicities of 2-BP. Pregnant rats received 1000 mg/kg/day subcutaneous 2-BP injections on gestational days (GD) 6 through 10 (Group II and Group IIII) or 11 through 15 (Group IV). Pregnant rats in Group III received an intraperitoneal PB injection once daily at 80 mg/kg/day on GD 3 through 5 for induction of the liver metabolic enzyme system. Control rats received vehicle injections only on GD 6 through 15. All dams underwent caesarean sections on GD 20 and their fetuses were examined for external, visceral, and skeletal abnormalities. Significant adverse effects on pregnant dams and embryo-fetal development were observed in all the treatment groups, and the maternal and embryo-fetal effects of 2-BP observed in Group II were higher than those seen in Group IV. Conversely, maternal and embryo-fetal developmental toxicities observed in Group III were comparable to those seen in Group II. These results suggest that the potential effects of 2-BP on pregnant dams and embryo-fetal development are more likely in the first half of organogenesis (days 6~10 of pregnancy) than in the second half and that the metabolic activation induced by PB pre-treatment did not modify the developmental toxic effects of 2-BP in rats.

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