Reactive Astrocyte Gliosis: Production of Inhibitory Molecules

The astrocytic cell responses to injury have been extensively studied in a variety of experimental models, and the term “astrogliosis” is often used to describe the astrocyte reactions to injury. Cells responding in these ways to injury are often referred to as “reactive astrocytes.” Glial scarring appears to be a critical feature of wound healing in the central nervous system (CNS), since elimination of the mitotically active contingent of reactive astrocytes leads to increase in the size of the wound. Reactive astrogliosis is a term coined for the morphological and functional events seen in astrocytes responding to CNS injury. The concept of reactive astrogliosis and its molecular and cellular definition in spinal cord injury (SCI) is still incomplete. Producing several inhibitory molecules discourages regeneration of axons in the injured spinal cord. This inhibition is compounded by the poor regenerative ability of most CNS axons. This is probably a more achievable therapeutic target than axon regeneration, and an effective treatment would be of assistance to the majority of patients with partial cord injuries. Of course, understanding about astrogliosis and producing mediators and inhibitory molecules such as signaling pathways help us to develop new treatment strategies for SCI

Genistein inhibits aggregation of exogenous amyloid-beta1-40 and alleviates astrogliosis in the hippocampus of rats. Brain Res

Abstract We addressed the question of whether injection of Aβ in the rat brain is associated with pathology in the hippocampus, and if genistein has any protective effect against the neuronal damage caused by Aβ 1-40 . Genistein is a plant-derived compound with a structure similar to that of the female sex hormone oestrogen and it was recently shown that pretreatment with a single dose of genistein ameliorated learning and memory deficits in an amyloid beta (Aβ) 1-40 rat model of Alzheimer's disease. Here, we report that injection of the amyloid peptide into the hippocampus of rats led to formation of Aβ 1-40 positive aggregates close to the lateral blade of the dentate gyrus (DGlb). We also observed the following in the hippocampus: extensive cell death in the DGlb (P < 0.0001), CA1 (P = 0.03), and CA3 (P = 0.002); an increased number of iNOS-expressing cells (P = 0.01) and gliosis. Genistein given to rats by gavage one hour before Key words: amyloid-beta, Alzheimer's disease, genistein, neuronal degeneration 1 1 Abbreviations: AD, Alzheimer's disease; iNOS, inducible nitric oxide synthase; nNOS, neuronal nitric oxide synthase; CA1, cornu ammonis 1; CA2, cornu ammonis 2; CA3, cornu ammonis 3; Aβ, amyloid beta; DGlb, lateral blade of dentate gyrus; DGmb, medial blade of dentate gyrus; GFAP, glial fibrillary acidic protein; CC, corpus callosum; MAP, mitogenactivated protein; NFĸB, nuclear factor kappa B; MnSOD, manganese superoxide dismutase; APP, amyloid precursor protein; CrEL, Cremophor E

Contra-lateral Auditory Brainstem Responses in Dyslexia

How to Cite This Article: Akbari M, Joghataei MT, Poorbakhat A, Jenabi MS. Contra-lateral auditory Brainstem Responses in Dyslexia. Iran J Child Neurol. Autumn 2016; 10(4): 10-15. AbstractObjectiveDyslexia is a neurological dysfunction (also known as a learning disability) that characterized by disability in reading in spite of normal intelligence. Bothe genetic and environmental risk factors are contributing into the condition.Diagnosis of dyslexia is based on examination and investigation of the patient’s memorial, spelling, visual, and reading skills. It is the most common learning disability, affecting 3%–10% of the school population. Modern neuroimaging techniques such as functional magnetic resonance imaging (fMRI) have shown a correlation between both functional and structural differences in the brains of children with reading difficulties. Hence, to address this issue, the auditory brainstem responses of children with dyslexia were investigated.  Materials &Methods Fifty two children with dyslexia (30 males, 22 females) were selected after examination by speech therapist. In addition, fifty two control children were included as well. The IPSI and contralateral ABR tests were conducted on both cases and controls. Click stimuli were used at 75 nHL intensity. The study focused on absolute latency of wave V in both groups. ResultsAbsolute latency of wave V in contralateral showed differences between children with dyslexia and control group, but no significant results were found in IPSI testing. ConclusionThe current data provide an evidence for brainstem and its function in signal processing and the role of brainstem nucleus on processing and delivering the information to each hemisphere.  References1. Lyon GR, Shaywitz SE, Shaywitz BA. 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Prevention of diagnostic errors in position of conus medullaris in adult patients

Background: Finding the safe location of spinal cord for cerebrospinal fluid (CSF) during surgical procedures is very important due to its various nature for each patient as well as its potential peripheral nervous system hazards. The aim of this study was to find the relationship between the location of conus medullaris (CM) and gender, age and body mass index (BMI) in order to minimize the potential diagnostic errors. Methods: Magnetic resonance imaging (MRI) with T1-weighted sagittal spin echo sequences of the lumbar spine was studied in 350 patients older than 20 years, whom had been referred for imaging in order to assess the potential causes of low back pain of the lumbar spine, and were referred to Shahid Chamran MRI center in Sanandaj, located in the west of Iran in 2014. The results were compared with international standards to reveal the potential errors. Results: In different age groups, the mean position was variable ranging from T12-L1 intervertebral disc to upper part of L1 middle third, not clinically significant. The inter canal position of the spinal cord was toward dorsal. No significant relationship was found between CM and gender, age as well as BMI. Similar relationship was found for the spinal cord position in spinal column. Conclusion: There is a safe region of 2–4 vertebral bodies and intervertebral spaces during spinal block. It means that the variation of CM position and its end level could be a guidance to realize that why neurological symptoms may vary in different patients

COVID-19 AND FEAR, WHICH COMES FIRST?

Today people have a few unanswered questions in their mind, such as "Do negative emotions will co-survive with the COVID-19 pandemic? Which one is worse? Which one will disappear quicker? Is there any connection between negative emotions and being infected by COVID-19 or the severity of infected individual\u27s symptoms ? How are we supposed to live with COVID-19 and adapt our emotional system to the virus for more than one upcoming year? These uncertainties could result in massive pressure on people. While there is no clear consensus regarding what establishes psychological stress on an individual, the effect of negative affect and psychological stress on increased susceptibility to disease due to altered immune functions is well established. Here we are going through the possible effect of emotions associated with the present pandemic on COVID-19 course of disease and severity of symptoms

Mesenchymal Stem Cell Therapies for Paraplegia: Preclinical and Clinical Studies

Paraplegia is the damage or loss of function in motor and/or sensory abilities. This insult can be observed in the thoracic, lumbar, or sacral parts of spinal column. Besides, paraplegia may be occurring because of any injuries or diseases of the lower segments or peripheral nerves or by cerebral palsy (CP). This damage can be seen as a result of a tumor or blood clot on the spinal cord. By now, there is not any curative treatment for paraplegia. Using mesenchymal stem cells (MSCs) in the treatment of spinal cord injury is a promising tested strategy because of their simplicity of isolation/preservation and their properties. Several preclinical studies in this field can be found; however, MSCs showed weak and conflicting outcomes in trials. In this chapter book, we will discuss about the therapeutic role of these cells in the treatment of paraplegia, with emphasis on their characterization, relevance, boundaries, and prospect views

COVID-19 AND FEAR, WHICH COMES FIRST?

Today people have a few unanswered questions in their mind, such as "Do negative emotions will co-survive with the COVID-19 pandemic? Which one is worse? Which one will disappear quicker? Is there any connection between negative emotions and being infected by COVID-19 or the severity of infected individual\u27s symptoms ? How are we supposed to live with COVID-19 and adapt our emotional system to the virus for more than one upcoming year? These uncertainties could result in massive pressure on people. While there is no clear consensus regarding what establishes psychological stress on an individual, the effect of negative affect and psychological stress on increased susceptibility to disease due to altered immune functions is well established. Here we are going through the possible effect of emotions associated with the present pandemic on COVID-19 course of disease and severity of symptoms

Evaluating a new verbal working memory-balance program: a double-blind, randomized controlled trial study on Iranian children with dyslexia

Abstract: Background: It is important to improve verbal Working Memory (WM) in reading disability, as it is a key factor in learning. There are commercial verbal WM training programs, which have some short-term effects only on the verbal WM capacity, not reading. However, because of some weaknesses in current verbal WM training programs, researchers suggested designing and developing newly structured programs that particularly target educational functions such as reading skills. In the current double-blind randomized clinical trial study, we designed a new Verbal Working Memory-Balance (VWM-B) program which was carried out using a portable robotic device. The short-term effects of the VWM-B program, on verbal WM capacity, reading skills, and postural control were investigated in Iranian children with developmental dyslexia. Results: The effectiveness of the VWM-B program was compared with the VWM-program as a traditional verbal WM training. In comparison with VWM-program, the participants who received training by the VWM-B program showed superior performance on verbal WM capacity, reading skills, and postural control after a short-term intervention. Conclusions: We proposed that the automatized postural control resulting from VWM-B training had a positive impact on improving verbal WM capacity and reading ability. Based on the critical role of the cerebellum in automatizing skills, our findings support the cerebellar deficit theory in dyslexia. Trial registration: This trial was (retrospectively) registered on 8 February 2018 with the Iranian Registry of Clinical Trials (IRCT20171219037953N1)

Clinimetrics of the Freezing of Gait Questionnaire for Parkinson Disease During the "off" State

Introduction: Freezing of gait, a common PD motor symptom, could increase the risk of falling. This study aimed to investigate the clinimetric attributes of the Freezing of Gait Questionnaire (FOGQ) for people with Parkinson disease in the "off" state. Methods: A total of 115 patients with Parkinson disease (PD; mean age, 60.25 years) were included. Acceptability, internal consistency (by the Cronbach alpha, and test-retest by Intraclass Correlation [ICC]), and reliability of the Persian-translated version of the FOGQ were examined. Dimensionality was estimated by Exploratory Factor Analysis (EFA). Fall efficacy scale-international, unified Parkinson disease rating scale-II, Berg balance scale, functional reach test, and Parkinson disease questionnaire-39 were applied to determine the convergent validity. Diagnostic accuracy for obtaining optimal cutoff point, separating faller and non-faller groups, was analyzed by Receiver Operating Characteristics (ROC) curve analysis and Area Under the Curve (AUC). All tests were carried out in an "off" state. Results: The Cronbach alpha was high (α=0.92). The test-retest showed high reliability (ICC=0.89). The FOGQ was unidimensional according to the EFA and had acceptable convergent validity with moderate to high correlation with other clinical scales. The optimal cutoff point to discriminate fallers from non-fallers during the "off" state was 9/10, with an AUC of 0.92. Conclusion: Our results suggest that the FOGQ has appropriate reliability, validity, and discriminative ability for measuring FOG in patients with PD during the "off" state.S