Biomedical subjects

I Chemale

Publications and source records attributed to I Chemale.

4 recordsLinked to original sources

PubMed2001

Increased serum S100beta protein concentrations following severe head injury in humans: a biochemical marker of brain death?

This study investigated S100beta protein as a biochemical serum marker of brain damage in severe head injury and brain death victims. Blood samples obtained from 15 patients with severe head injury admitted to the trauma intensive care unit (ICU), five patients with a diagnosis of brain death due to hemorrhage following cerebral aneurysm rupture, and five healthy individuals were investigated. The S100beta protein serum concentrations were analyzed with a immunoradiometric assay kit. The 15 patients with severe head injury were followed up for 6 months. Outcome was considered either death or recovery with ICU discharge. S100beta concentrations were closely related to brain damage. Among the severe head injury victims, higher S100beta concentrations were detected in those patients that progressed to death. The individuals with brain death had similar mean S100beta concentrations, irrespective of its cause (either trauma or vascular rupture). S100beta protein is a promising serum outcome predictor for severe head injury victims and may contribute to the early diagnosis of brain death.

Adolescent↗

PubMed2001

Neurochemical characterization of traumatic brain injury in humans.

Trauma is the leading cause of death in individuals between the ages of 1 and 44 years. And, in the case of severe head injury mortality can reach as high as 35-70%. Despite this fact, there has been little progress in the development of effective pharmacological agents to protect brain injured patients. To date, there is little data on the mechanisms involved in neuronal cellular insult after severe head injury, especially in humans. Glutamate acts both as a primary excitatory neurotransmitter and a potential neurotoxin within the mammalian brain. Evidence indicates that hyperactivity of the glutamate system contributes to neuronal death in brain trauma. Also, in animal models of neurotrauma, this neural injury is followed by gliosis which has been linked to the severity of brain injury. To investigate the glutamate system in brain trauma, we carried out [3H]glutamate and [3H]MK801 (a noncompetitive NMDA-receptor antagonist) binding and [3H]glutamate uptake assays in human cerebral cortex preparations obtained from severely brain injured and control victims. Additionally, to investigate gliosis following brain injury, we performed GFAP immunohistochemistry. There were no significant differences in [3H]glutamate binding (affinity or density of sites) between the control and head injured groups. In contrast, cerebral cortical [3H]MK801 binding revealed both a significant increase in the density of sites (Bmax) and a decrease in the dissociation constant (Kd) in the head injured group when compared to controls. There were no significant differences in [3H]glutamate uptake between groups. The injured brains presented an increased number of GFAP-positive astrocytes and more intense GFAP reaction in comparison to control brains. In the context of traumatic brain injury, our results encourage further investigation into compounds capable of selective modulation of NMDA receptor subtype in humans while also therapeutically manipulating glial cell responses following brain trauma.

Adolescent↗

PubMed1997

Guanine nucleotides are present in human CSF.

Several studies have shown that experimentally added guanine nucleotides (GN) may extracellularly modulate the glutamatergic system. However, there is no previous report of the extracellular occurrence of GN in the CNS. This study used HPLC to investigate the presence of GN in cerebrospinal fluid (CSF) samples of 26 patients. We demonstrated the extracellular presence of GN in the CNS. In human CSF, GMP was detected in a remarkably high concentration (236.20 microM). This evidence stimulates further investigation of extracellular GN modulation of neurotransmission, physiological mechanisms of action(s), and therapeutic potential(s) in the CNS.

Adenine Nucleotides↗

PubMed1986

Persistent primitive trigeminal artery aneurysm.

The trigeminal artery is the most common persistent carotid-basilar anastomotic channel observed in adult life, and its occurrence probably represents a defect in cerebrovascular development. It can be associated with other congenital abnormalities such as cerebral aneurysms, but only rarely do aneurysms of the primitive trigeminal artery itself arise. The authors present a new case of an aneurysm arising directly from the primitive trigeminal artery and discuss its significance and treatment.

Adult↗