ABSTRACT
Objective:To summarize the abnormalities in brain magnetic resonance imaging (MRI) and clinical manifestations of children with infantile spasms (IS) in the course of Vigabatrin (VGB) treatment.Methods:The imaging features of children with IS who took VGB orally and presented with brain MRI changes in Peking University First Hospital between September 2016 and June 2018 were analyzed retrospectively.Their use of VGB and the imaging findings were followed up.Meanwhile, the imaging and clinical features of 83 cases described in literature were summarized.Results:(1) Ten children diagnosed as IS were included.The average duration of VGB treatment at the time of imaging changes was 4.1 months, the average age was 11.8 months, and the average maximum dose was 90.6 mg/(kg·d). Brain MRI showed hyperintensities in bilateral thalamus, brainstem, basal ganglia and dentate nucleus diffusion-weight imaging (DWI), with or without T2WI, and T2 fluid attenuated inversion recovery(FLAIR) or slight hyperintensities.Brain MRI repeated in 5 patients 7-12 months later revealed that the original abnormal signals completely disappeared.Among them, 4 patients stopped using VGB and 1 patient continued to take VGB.(2) Literature review: 83 cases with IS treated with VGB from 16 literatures were reviewed, and the incidence of abnormal brain MRI was 22%-32%.The average age at initial VGB treatment was 8.0 months, and the average dose of VGB was 157.1 mg/(kg·d) when the brain MRI abnormalities were found.The MRI imaging showed high DWI signals in bilateral symmetrical thalamus, brainstem, basal ganglia (mainly pallidum) and dentate nucleus.During the follow-up of the 41 cases, no imaging abnormality was observed in 36 cases, improvement in 4 cases, and no significant change in 1 case.When MRI abnormalities were identified, 12.0%(10/83 cases) of the patients presented new clinical symptoms mainly in the extrapyramidal system, and the clinical symptoms of all children disappeared during the follow-up.Conclusions:During the course of VGB treatment of infantile spasms, brain MRI may suggest hyperintensities of DWI in the thalamus, brainstem, basal ganglia and dentate nucleus, but most are reversible.
ABSTRACT
Acoustic resolution photoacoustic microscopy (ARPAM) combines the advantages of high optical contrast, and high ultrasonic spatial resolution and penetration. However, in photoacoustic microscopy (PAM), the information from deep regions can be greatly affected by the shallow targets, and most importantly, the irreconcilable conflict between the lateral resolution and depth of fields has always be a major factor that limits the imaging quality. In this work, an ARPAM system was developed, in which a non-coaxial arrangement of light illumination and acoustic detection was adopted to alleviate the influence of the tissue surface on the deep targets, and a novel focal zone integral algorithm was applied with multiple axial scanning to improve the lateral resolution. Phantom experiment results show that, the build system can maintain a consistent high lateral resolution of 0.6 mm over a large range in axial direction, which is close to the theoretical calculations. The following tumor imaging results on nude mice indicate that, the proposed method can provide more in-depth information compared with the conventional back detection ARPAM method. With the development of fast repetition lasers and image scanning technologies, the proposed method may play an important role in cerebral vascular imaging, cervical cancer photoacoustic endoscopic detection, and superficial tumor imaging.
ABSTRACT
Mitochondria homeostasis is essential to cell activities,while mitochondrial dysfunction is involved in the pathogenesis of many muscular diseases,such as congenital myopathy and muscular dystrophy.However,its detailed mechanism has not been clarified.Mitofusin-2 (Mfn2) is located in the outer mitochondrial membranes and endoplasmic reticulum(ER) mitochondrial contact sites.Recently,researchers have found that in addition to its participation in tethering mitochondiia to mitochondria and ER to mitochondria,Mfn2 regulates mitochondrial dynamics and multiple cellular processes including oxidative stress,Ca2 + signaling pathways,energy metabolism,and PINK1/Parkin induced mitophagy,playing an important role in maintaining the mitochondrial quality control.And abnormal expression of Mfn2 also related to many kinds of pathological states.Here we review its molecular structure and recent advances in the role of Mfn2 in maintaining mitochondrial homeostasis in skeletal muscle.