Astrocytic Response to Acutely- and Chronically-Implanted Microelectrode Arrays in the Marmoset (Callithrix jacchus) Brain

Microelectrode implants are an important tool in neuroscience research and in developing brain–machine interfaces. Data from rodents have consistently shown that astrocytes are recruited to the area surrounding implants, forming a glial scar that increases electrode impedance and reduces chronic utility. However, studies in non-human primates are scarce, with none to date in marmosets. We used glial fibrillary acidic protein (GFAP) immunostaining to characterize the acute and chronic response of the marmoset brain to microelectrodes. By using densitometry, we showed that marmoset astrocytes surround brain implants and that a glial scar is formed over time, with significant increase in the chronic condition relative to the acute condition animal.

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Changes in Plasma Glial Fibrillary Acidic Protein in Children Receiving Sevoflurane Anesthesia: A Preliminary Randomized Trial

Journal of Clinical Medicine ◽

10.3390/jcm10040662 ◽

2021 ◽

Vol 10 (4) ◽

pp. 662

Author(s):

Eun-Hee Kim ◽

Young-Eun Jang ◽

Sang-Hwan Ji ◽

Ji-Hyun Lee ◽

Sung-Ae Cho ◽

...

Keyword(s):

Glial Fibrillary Acidic Protein ◽

Randomized Trial ◽

Protein Concentration ◽

Pediatric Patients ◽

Neuronal Injury ◽

Acidic Protein ◽

Anesthesia Induction ◽

Sevoflurane Anesthesia ◽

Control Groups ◽

Over Time

We investigated changes in plasma glial fibrillary acidic protein concentration during sevoflurane anesthesia induction in children < 3 years old and determined the effect of co-administering dexmedetomidine. This preliminary randomized trial included 60 pediatric patients who received sevoflurane anesthesia for >3 h. Patients were assigned to dexmedetomidine or control groups at a 1:1 ratio. The primary outcome was changes in plasma glial fibrillary acidic protein concentration of dexmedetomidine and control groups over time. Fifty-five patients were included in the final analysis. The median (interquartile range (IQR)) of the plasma glial fibrillary acidic protein level was 387.7 (298.9–510.8) pg·mL−1 immediately after anesthetic induction, 302.6 (250.9–412.5) pg·mL−1 at 30 min, and 321.9 (233.8–576.2) pg·mL−1 at 180 min after the first sample. These values did not change over time (p = 0.759). However, plasma glial fibrillary acidic protein increased after 180 min of infusion of dexmedetomidine compared with values at 30 min infusion (p = 0.04, mean difference and 95% confidence interval of 221.6 and 2.2 to 441.0 pg·mL−1). In conclusion, three hours of sevoflurane anesthesia in pediatric patients < 3 years old did not provoke neuronal injury assessed by the plasma biomarker. Further studies regarding the effect of prolonged dexmedetomidine infusion on anesthetic neuronal injury are required.

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How Serious is the Hoarding Problem?

Hoarding ◽

10.1093/wentk/9780190946395.003.0006 ◽

2020 ◽

Author(s):

Gail Steketee ◽

Christiana Bratiotis

Keyword(s):

Mental Health ◽

Mental Health Problem ◽

Health Problem ◽

Chronic Condition ◽

Over Time

How do I know when my saving is really a problem? As we indicated in Chapter 2, hoarding is a chronic condition that is likely to worsen over time if left untreated. This initially private mental health problem can rapidly become a significant...

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Paraphimosis revisited: is chronic paraphimosis a predominantly third world condition?

Tropical Doctor ◽

10.1258/td.2007.006212 ◽

2008 ◽

Vol 38 (1) ◽

pp. 40-42 ◽

Cited By ~ 4

Author(s):

M Rangarajan ◽

S M Jayakar

Keyword(s):

Chronic Condition ◽

Third World ◽

New Classification ◽

The Third ◽

Long Term Follow Up ◽

Initial Injury ◽

Acute Condition

Paraphimosis is an acute condition characterized by all the signs of inflammation. Here we describe a ‘chronic’ variant of paraphimosis where patients often present many days after the initial injury. The aim of this study is to identify and possibly classify this new variation of paraphimosis – the chronic condition. We studied 68 patients with this condition between 1997 and 2005. In all, the prepuce was fibrous and bunched up behind the glans penis and, in some cases, with ulcerations. All patients were treated by excision of the fibrous flap and circumcision, under local anaesthesia. Patients were discharged on the same dayon which the excision was done. Follow-up was on the third, seventh and ninetieth days. Long-term follow-up was possible in only 22 patients. This technique of modified circumcision was effective in treating this condition and we think a new classification of paraphimosis is warranted – acute and chronic.

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Abnormal Reaction to Central Nervous System Injury in Mice Lacking Glial Fibrillary Acidic Protein and Vimentin

The Journal of Cell Biology ◽

10.1083/jcb.145.3.503 ◽

1999 ◽

Vol 145 (3) ◽

pp. 503-514 ◽

Cited By ~ 239

Author(s):

Milos Pekny ◽

Clas B. Johansson ◽

Camilla Eliasson ◽

Josefina Stakeberg ◽

Åsa Wallén ◽

...

Keyword(s):

Spinal Cord ◽

Central Nervous System ◽

Nervous System ◽

Glial Fibrillary Acidic Protein ◽

Intermediate Filament ◽

Glial Scar ◽

Scar Formation ◽

Brain Lesions ◽

Acidic Protein ◽

The Central Nervous System

In response to injury of the central nervous system, astrocytes become reactive and express high levels of the intermediate filament (IF) proteins glial fibrillary acidic protein (GFAP), vimentin, and nestin. We have shown that astrocytes in mice deficient for both GFAP and vimentin (GFAP−/−vim−/−) cannot form IFs even when nestin is expressed and are thus devoid of IFs in their reactive state. Here, we have studied the reaction to injury in the central nervous system in GFAP−/−, vimentin−/−, or GFAP−/−vim−/− mice. Glial scar formation appeared normal after spinal cord or brain lesions in GFAP−/− or vimentin−/− mice, but was impaired in GFAP−/−vim−/− mice that developed less dense scars frequently accompanied by bleeding. These results show that GFAP and vimentin are required for proper glial scar formation in the injured central nervous system and that some degree of functional overlap exists between these IF proteins.

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Brain-machine interfaces using thin-film silicon microelectrode arrays

2004 IEEE International Symposium on Circuits and Systems (IEEE Cat. No.04CH37512) ◽

10.1109/iscas.2004.1329691 ◽

2004 ◽

Author(s):

D.R. Kipke

Keyword(s):

Thin Film ◽

Microelectrode Arrays ◽

Brain Machine Interfaces ◽

Thin Film Silicon

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New approaches for the implementation of minimally invasive microelectrode arrays designed for brain-machine interfaces

Proceedings of the 25th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (IEEE Cat. No.03CH37439) ◽

10.1109/iembs.2003.1280987 ◽

2004 ◽

Cited By ~ 1

Author(s):

S. Martel ◽

T. Fofonoff

Keyword(s):

Minimally Invasive ◽

Microelectrode Arrays ◽

Brain Machine Interfaces ◽

New Approaches

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Dimethyl fumarate as a safe and effective therapy for recalcitrant psoriasis in comorbid patients

Dermatology Reports ◽

10.4081/dr.2021.9091 ◽

2021 ◽

Author(s):

Martina Burlando ◽

Mattia Fabio Molle ◽

Emanuele Cozzani ◽

Aurora Parodi

Keyword(s):

Systemic Therapy ◽

Clinical Remission ◽

Chronic Condition ◽

Treatment Options ◽

Dimethyl Fumarate ◽

Severe Psoriasis ◽

Biological Therapies ◽

Biological Drugs ◽

Effective Choice ◽

Over Time

Psoriasis is a chronic condition for which multiple therapies are currently available. In particular, in cases of moderate-severe psoriasis, traditional systemic drugs or the new biological drugs can be administered. However, the treatment of patients who require systemic therapy and have multiple comorbidities can be particularly complex. Some treatment options may be in fact contraindicated or may lose effectiveness over time, reducing the options available to the dermatologists. In such circumstances, dimethyl fumarate may represent a safe and effective choice, also in patients who have already attempted biological therapies. In this regard, we report the case of a patient with moderatesevere psoriasis treated over time with various therapies (including topicals, phototherapy, traditional and biological drugs) that were discontinued due to ineffectiveness or incompatibility caused by the occurrence of concomitant diseases, who finally achieved clinical remission with dimethyl fumarate.

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Role of laminin bioavailability in the astroglial permissivity for neuritic outgrowth

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652002000400009 ◽

2002 ◽

Vol 74 (4) ◽

pp. 683-690 ◽

Cited By ~ 14

Author(s):

MARCIENNE TARDY

Keyword(s):

Glial Fibrillary Acidic Protein ◽

Neurite Outgrowth ◽

Axonal Regeneration ◽

Glial Scar ◽

Reactive Astrocytes ◽

Adult Brain ◽

Morphological Response ◽

Phenotypic Changes ◽

Neuritic Outgrowth

The mechanisms involved in the failure of an adult brain to regenerate post-lesion remain poorly understood. The reactive gliosis which occurs after an injury to the CNS and leads to the glial scar has been considered as one of the major impediments to neurite outgrowth and axonal regeneration. A glial scar consists mainly of reactive, hypertrophic astrocytes. These reactive cells acquire new properties, leading to A non-permissive support for neurons. Astrogial reactivity is mainly characteriized by a high overexpression of the major component of the gliofilaments, the glial fibrillary acidic protein (GFAP). This GFAP overexpression is related to the astroglial morphological response to injury. We hypothesized that modulation of GFAP synthesis, reversing the hypertrophic phenotype, might also reverse the blockage of neuritic outgrowth observed after a lesion. In this article, we review findings of our group, confirming our hypothesis in a model of lesioned neuron-astrocyte cocultures. We demonstrate that permissivity for neuritic outgrowth is related to phenotypic changes induced in reactive astrocytes transfected by antisense GFAP-mRNA. We also found that this permissivity was related to a neuron-regulated extracellular laminin bioavailability.

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DOES ONSET OF CHRONIC CONDITIONS MODERATE THE IMPACT OF RELATIONAL LIFE EVENTS ON DEPRESSED MOOD?

Innovation in Aging ◽

10.1093/geroni/igz038.970 ◽

2019 ◽

Vol 3 (Supplement_1) ◽

pp. S260-S260

Author(s):

Aaron M Ogletree ◽

Rosemary Blieszner ◽

Rachel Pruchno ◽

Jyoti Savla ◽

Laura P Sands

Keyword(s):

Mental Health ◽

Older Adults ◽

Depressive Symptoms ◽

Life Events ◽

Chronic Conditions ◽

Chronic Condition ◽

Process Model ◽

Mixed Effect ◽

The Impact ◽

Over Time

Abstract More than 62% of adults aged 65+ have more than one chronic condition; this number increases to more than 82% for those 85+. Older adults simultaneously experience changes in their relationships due to negative relational life events, including illness, injury, or death of a loved one. Stressors occurring in tandem can overload psychological resources and increase risk for poor mental health. Informed by the stress process model, we assessed the influence of relational life events on depressive symptoms over time and evaluated the moderating effects of chronic condition onset. Self-reports of four stressful life events, five chronic conditions, and depressive symptoms as measured by the CES-D came from 2,948 older adults participating in the ORANJ BOWL panel. Using longitudinal multilevel mixed effect modeling, we examined trajectories of depressive symptoms across three waves. While depressive symptoms increased over time, they were greater for people who experienced more relational life events and the onset of more chronic conditions. Participants who reported experiencing all four relational life events but no chronic conditions had an average CES-D score of 5.28 (p<.0001); average CES-D score increased to 12.72 (p<.0001) for those who reported four life events and the onset of four or more new chronic conditions during the study period. In summary, chronic condition onset moderated the relationship between life events and depressive symptoms. Findings highlight the need for practitioner awareness of increased mental health risks for people experiencing stressors in multiple domains of life.

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