Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0268318 (ICP)
 10,007 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The number of parameters (i.e., EEG or ICP-intracranial pressure) routinely monitored under clinical situations is limited. The brain function analyzer described in this paper enables simultaneous, continuous on-line monitoring of cerebral blood flow (CBF) and volume (CBV), intramitochondrial NADH redox state, extracellular K+ concentrations, DC potential, electrocorticography and ICP from the cerebral cortex. Brain function of 14 patients with severe head injury (GCS < or = 8), who were hospitalized in the neurosurgical or general intensive care unit was monitored using this analyzer. Leao cortical spreading depression (SD) has been reported in many experimental animals but not in the human cerebral cortex. In one of the patients monitored, spreading depression was observed. This is the first time that spontaneous repetitive cortical SD cycles have been recorded from the cerebral cortex of a patient suffering from severe head injury. Typical SD cycles appeared 4-5 h after the beginning of monitoring this patient. During the first 3-4 cycles the responses of this patient were very similar to the responses to SD recorded in normoxic experimental animals. Electrocorticography was depressed whereas extracellular K+ levels increased. The metabolic response to spreading depression was characterized by oxidation of intramitochondrial NADH concomitant to a large increase in CBF. During brain death, an ischemic depolarization, characterized by decrease in CBF and an irreversible increase in extracellular K+, was recorded.
 ...
PMID:Cortical spreading depression recorded from the human brain using a multiparametric monitoring system. 897 24

In order to evaluate the relationship between brain oxygen supply and demand (O2 balance) in real time, it is necessary to use a multiparametric monitoring approach. Cerebral blood flow (CBF) is a representative parameter of O2 supply. The extracellular level of K+ is a reliable indicator of O2 demand since more than 60% of the energy consumed by the brain is utilized by active transport processes. Mitochondrial NADH redox state can represent the balance between O2 supply and demand. In order to monitor the brain of experimental animals or patients, we constructed the multiparametric assembly (MPA) and the following parameters were monitored simultaneously and in real time: CBF, CBV, NADH redox state, extracellular K+, DC potential, EEG, tissue temperature and ICP. Animals were exposed to hypoxia, ischemia, hypercapnia, hyperoxia and spreading depression (SD) and the relative changes in CBF and NADH were calculated and found to be significant indicators of brain energy state. Monitoring these two parameters increases the possibility of differentiating between various pathophysiological states. Each added parameter increases the power of diagnosis and determination of the functional state of the brain. Preliminary results obtained in patients monitored in the ICU or in the OR show that the responses to hypercapnia, spreading depression or ischemia are similar to those measured in experimental animals.
 ...
PMID:Multiparametric monitoring of brain oxygen balance under experimental and clinical conditions. 958 30

The brain of neurosurgical patients are exposed to various manipulations in the ICU or during surgery. Under such conditions brain O2 balance may become negative and as a result brain vitality and function will deteriorate. In order to evaluate brain vitality in real time it is important to measure more than one parameter. The multiparametric monitoring system used in our previous study to monitor comatose patients (Mayevsky et al., Brain Res. 740: 268-274, 1996) was changed into a "simplified" tissue spectroscope for real time monitoring of brain O2 balance. Mitochondrial function was evaluated by monitoring the NADH redox state by surface fluorometry. Microcirculatory blood flow was assessed by laser Doppler flowmetry. The combined optical probe was located on the surface of the brain during various neurosurgical procedures and the responses were recorded and presented in real time to the surgeon. A total of 32 patients were monitored during various procedures. The results could be summarized as follows: 1. Hypercapnia led to 3 different types of responses. In two patients the 'stealing' like event was recorded. In the other 7 patients the responses to high CO2 was not detectable. In the last group of 6 patients a clear CBF elevation was recorded with variable response of mitochondrial NADH. 2. Our monitoring device was able to evaluate the efficacy of the STA-MCA anastomosis during aneurysm surgery. 3. A significant correlation was recorded between CBF and NADH redox state during changes in blood pressure, papaverine injection, spontaneous drop in blood supply to the brain or during releasing of high ICP levels. We conclude that in order to evaluate the metabolic state of the brain during neurosurgical procedures it is necessary to monitor both CBF and mitochondrial NADH by using the tissue spectroscope.
 ...
PMID:The evaluation of brain CBF and mitochondrial function by a fiber optic tissue spectroscope in neurosurgical patients. 1216 49

The 'Cushing Response' is a significant phenomenon associated with elevated ICP. The purpose of our study was to examine the effects of the intracranial hypertension level and duration on the cerebral tissue physiology, using a Multiprobe assembly (MPA). The parameters monitored simultaneously included ICP, CBF, mitochondrial NADH redox state, extracellular K+ and H+ levels, DC potential and ECoG, calculated CPP and blood pressure. Two groups of rats were used. In one group, ICP was elevated to 50-60 mmHg for 13-15 min and, in the second group, ICP was elevated to 20 mmHg for 30 min. The results show that ICP of 50-60 mmHg led to CPP reduction below the lower limits of autoregulation. However, ICP of 20 mmHg, even for a prolonged period of time is completely tolerated. Additionally, we found that the 'Cushing Response', developed in the moderate treatment (ICP = 20 mmHg) is beneficial, assuring high CBF levels under intracranial hypertension. Furthermore, CBF and CPP monitoring, apparently, are not sufficient for autoregulation assessment; more parameters are needed.
 ...
PMID:Effects of elevated ICP on brain function: can the multiparametric monitoring system detect the 'Cushing Response'? 1256 25

The copper(II) complexes of bis-thiosemicarbazones (Cu(btsc)) such as Cu(atsm) and Cu(gtsm) are neutral, lipophilic compounds that show promise as therapeutics for the treatment of certain neurological diseases and cancers. Although the effects of these compounds have been described at the cellular level, there is almost no information about their biochemical mode of action. In this work, we showed that Cu(atsm) and Cu(gtsm) displayed antimicrobial activities against the human obligate pathogen Neisseria gonorrhoeae that were more than 100 times more potent than Cu(NO3)2 salt alone. Treatment with Cu(btsc) also produced phenotypes that were consistent with copper poisoning, but the levels of intracellular copper were undetectable by ICP MS. We observed that Cu(btsc) interacted with proteins in the cell membrane. Systematic measurements of O2 uptake further demonstrated that treatment with both Cu(atsm) and Cu(gtsm) led to dose-dependent inhibition of respiratory electron transfer processes via succinate and NADH dehydrogenases. These dehydrogenases were not inhibited by a non-btsc source of Cu(II). The results led us to conclude that the biochemical mechanism of Cu(btsc) action is likely more complex than the present, simplistic model of copper release into the cytoplasm.
 ...
PMID:Antimicrobial effects of copper(II) bis(thiosemicarbazonato) complexes provide new insight into their biochemical mode of action. 2443 65