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1.
Int J Mol Sci ; 24(8)2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-37108734

RESUMO

Extremely low frequency electromagnetic field (ELF-EMF) exists widely in public and occupational environments. However, its potential adverse effects and the underlying mechanism on nervous system, especially behavior are still poorly understood. In this study, zebrafish embryos (including a transfected synapsin IIa (syn2a) overexpression plasmid) at 3 h post-fertilization (hpf) were exposed to a 50-Hz magnetic field (MF) with a series of intensities (100, 200, 400 and 800 µT, respectively) for 1 h or 24 h every day for 5 days. Results showed that, although MF exposure did not affect the basic development parameters including hatching rate, mortality and malformation rate, yet MF at 200 µT could significantly induce spontaneous movement (SM) hypoactivity in zebrafish larvae. Histological examination presented morphological abnormalities of the brain such as condensed cell nucleus and cytoplasm, increased intercellular space. Moreover, exposure to MF at 200 µT inhibited syn2a transcription and expression, and increased reactive oxygen species (ROS) level as well. Overexpression of syn2a could effectively rescue MF-induced SM hypoactivity in zebrafish. Pretreatment with N-acetyl-L-cysteine (NAC) could not only recover syn2a protein expression which was weakened by MF exposure, but also abolish MF-induced SM hypoactivity. However, syn2a overexpression did not affect MF-increased ROS. Taken together, the findings suggested that exposure to a 50-Hz MF inhibited spontaneous movement of zebrafish larvae via ROS-mediated syn2a expression in a nonlinear manner.


Assuntos
Campos Magnéticos , Peixe-Zebra , Animais , Campos Eletromagnéticos/efeitos adversos , Larva/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Peixe-Zebra/metabolismo , Sinapsinas
2.
Bioelectromagnetics ; 37(4): 244-55, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27061713

RESUMO

Magnetic field exposure is an accepted safe and effective modality for nerve injury. However, it is clinically used only as a supplement or salvage therapy at the later stage of treatment. Here, we used a planarian Girardia sinensis decapitated model to investigate beneficial effects of early rotary non-uniform magnetic fields (RMFs) exposure on central nervous regeneration. Our results clearly indicated that magnetic stimulation induced from early RMFs exposure significantly promoted neural regeneration of planarians. This stimulating effect is frequency and intensity dependent. Optimum effects were obtained when decapitated planarians were cultured at 20 °C, starved for 3 days before head-cutting, and treated with 6 Hz 0.02 T RMFs. At early regeneration stage, RMFs exposure eliminated edema around the wound and facilitated subsequent formation of blastema. It also accelerated cell proliferation and recovery of neuron functionality. Early RMFs exposure up-regulated expression of neural regeneration related proteins, EGR4 and Netrin 2, and mature nerve cell marker proteins, NSE and NPY. These results suggest that RMFs therapy produced early and significant benefit in central nervous regeneration, and should be clinically used at the early stage of neural regeneration, with appropriate optimal frequency and intensity.


Assuntos
Sistema Nervoso Central/fisiologia , Campos Magnéticos , Regeneração Nervosa , Planárias/fisiologia , Rotação , Animais , Biomarcadores/metabolismo , Regulação da Expressão Gênica , Temperatura , Fatores de Tempo
3.
Audiol Res ; 13(5): 821-832, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37887853

RESUMO

There are several pathologies that can change the anatomy of the otic capsule and that can distort the bone density of the bony structures of the inner ear, but otosclerosis is one of the most frequent. Similar behavior has been shown in patients affected by osteogenesis imperfecta (OI), a genetic disorder due to a mutation in the genes coding for type I (pro) collagen. In particular, we note that otosclerosis and OI can lead to bone resorption creating pericochlear cavitations in contact with the internal auditory canal (IAC). In this regard, we have collected five cases presenting this characteristic; their audiological data and clinical history were analyzed. This feature can be defined as a potential cause of a third-window effect, because it causes an energy loss during the transmission of sound waves from the oval window (OW) away from the basilar membrane.

4.
J Med Imaging (Bellingham) ; 3(2): 025501, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27284549

RESUMO

Stereoscopic medical videos are recorded, e.g., in stereo endoscopy or during video recording medical/dental operations. This paper examines quality issues in the recorded stereoscopic medical videos, as insufficient quality may induce visual fatigue to doctors. No attention has been paid to stereo quality and ensuing fatigue issues in the scientific literature so far. Two of the most commonly encountered quality issues in stereoscopic data, namely stereoscopic window violations and bent windows, were searched for in stereo endoscopic medical videos. Furthermore, an additional stereo quality issue encountered in dental operation videos, namely excessive disparity, was detected and fixed. The conducted experiments prove the existence of such quality issues in stereoscopic medical data and highlight the need for their detection and correction.

5.
Indian J Otolaryngol Head Neck Surg ; 54(3): 198-203, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23119892

RESUMO

Bell's palsv or acute idiopathic lower motor neuron facial palsy is a common cause of facial palsy seen in clinical practice. The cause of this disease is not exactly known though there arc many theories regarding Ils etiology. In this article, we present the theory of "Tertiary is chacmia " in eases of pertinent Bell's palsy. Our concept of Tertiary ischaemia is further supported by histological findings of the nerve sheath biopsy taken during surgical decompression In eases of Bell' s palsy. The procedure, of performing posterior tympanotomy and improving the exposure of the middle ear structures therein is also explained.

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