Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0917798 (cerebral ischemia)
 17,036 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We report significant neurological abnormality at 18 months of age in 3 of 7 very low birth weight infants (less than or equal to 1,500 g), who during mechanical ventilation inadevertently became severely hypocarbic (arterial carbondioxide tension less than 2.0 kPa (15 mmHg)) at some time during the first 24 h of life. Although the number is small the outcome was significantly worse than the outcome in two fairly similar groups of infants selected as controls (p = 0.026). The infants in one of the control groups were also mechanically ventilated but remained normocapnic. Germinal layer haemorrhage (GLH) was more frequent among these infants compared with the severely hypocarbic infants (p = 0.022). The infants in the other control group was not mechanically ventilated. In all the severely hypocarbic infants the Bayley mental developmental index uncorrected for prematurity was at or below the median for the total sample (p = 0.01). The results suggest that neonatal cerebral ischaemia, for instance due to hypocarbia, is of greater prognostic significance than GLH.
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PMID:Severe hypocarbia in preterm infants and neurodevelopmental deficit. 244 Feb 26

Erythropoietin (Epo) is a hydrophobic sialoglycoproteic hormone produced by the kidney and responsible for the proliferation, maturation, and differentiation of the precursors of the erythroid cell line. Human recombinant erythropoietin (rHuEpo) is used to treat different types of anemia, not only in uremic patients but also in newborns with anemia of prematurity, in patients with cancer-related anemia or myeloproliferative disease, thalassemias, bone marrow transplants, or those with chronic infectious diseases. The pleiotropic functions of Epo are well known. It has been shown that this hormone can modulate the inflammatory and immune response, has direct hemodynamic and vasoactive effects, could be considered a proangiogenic factor because of its interaction with vascular endothelial growth factor, and its ability to stimulate mitosis and motility of endothelial cells. The multifunctional role of Epo has further been confirmed by the discovery in the central nervous system of a specific Epo/Epo receptor (EpoR) system. Both Epo and EpoR are expressed by astrocytes and neurons and Epo is present in the cerebrospinal fluid (CSF). Therefore, novel functions of Epo, tissue-specific regulation, and the mechanisms of action have been investigated. In this review we have tried to summarize the current data on the role of Epo on brain function. We discuss the different sites of cerebral expression and mechanisms of regulation of Epo and its receptor and its role in the development and maturation of the brain. Second, we discuss the neurotrophic and neuroprotective function of Epo in different conditions of neuronal damage, such as hypoxia, cerebral ischemia, and subarachnoid hemorrhage, and the consequent possibility that rHuEpo therapy could soon be used in clinical practice to limit neuronal damage induced by these diseases.
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PMID:The pleiotropic effects of erythropoietin in the central nervous system. 1263 27

Periventricular leukomalacia (PVL), the major substrate of cerebral palsy in survivors of prematurity, is defined as focal periventricular necrosis and diffuse gliosis in immature cerebral white matter. We propose that nitrosative and/or oxidative stress to premyelinating oligodendrocytes complicating cerebral ischemia in the sick premature infant is a key mechanism of injury interfering with maturation of these cells to myelin-producing oligodendrocytes and subsequent myelination. Using immunocytochemical markers in autopsy brain tissue from 17 PVL cases and 28 non-PVL controls, we found in the PVL cases: 1) selective regionalization of white matter injury, including preferential involvement of the deep compared to intragyral white matter; 2) prominent activation of microglia diffusely throughout the white matter; 3) protein nitration and lipid peroxidation in premyelinating oligodendrocytes in the diffuse component; 4) preferential death of premyelinating oligodendrocytes diffusely; and 5) virtual sparing of the overlying cerebral cortex, as demonstrated by markers of activated astrocytes and microglia. These data establish that PVL is primarily a white matter disease that involves injury to premyelinating oligodendrocytes, potentially through activation of microglia and release of reactive oxygen and nitrogen species. Agents that prevent nitrosative and oxidative stress may play a key role in ameliorating PVL in premature infants in the intensive care nursery.
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PMID:Nitrosative and oxidative injury to premyelinating oligodendrocytes in periventricular leukomalacia. 1276 84

Periventricular leukomalacia (PVL) is a lesion of the immature cerebral white matter in the perinatal period and associated predominantly with prematurity and cerebral ischemia/reperfusion as well as inflammation due to maternofetal infection. It consists of focal necrosis in the periventricular region and diffuse gliosis with microglial activation and premyelinating oligodendrocyte (pre-OL) injury in the surrounding white matter. We previously showed nitrotyrosine in pre-OLs in PVL, suggesting involvement of nitrosative stress in this disorder. Here we hypothesize that inducible nitric oxide synthase (iNOS) expression is increased in PVL relative to controls. Using immunocytochemistry in human archival tissue, the density of iNOS-expressing cells was determined in the cerebral white matter of 15 PVL cases [29-51 postconceptional (PC) weeks] and 16 control cases (20-144 PC weeks). Using a standardization score of 0-3, the density of iNOS-positive cells was significantly increased in the diffuse component of PVL (score of 1.8 +/- 0.3) cases compared to controls (score of 0.7 +/- 0.3) (P = 0.01). Intense iNOS expression occurred in reactive astrocytes in acute through chronic stages and in activated microglia primarily in the acute stage, suggesting an early role for microglial iNOS in PVL's pathogenesis. This study supports an important role for iNOS-induced nitrosative stress in the reactive/inflammatory component of PVL.
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PMID:Nitrosative stress and inducible nitric oxide synthase expression in periventricular leukomalacia. 1941 11

Creatine plays a central role in energy metabolism and is synthesized in the liver, kidney and pancreas. In healthy patients, it is transported via the blood stream to the muscles, heart and brain with high and fluctuating energy demands by the molecule creatine transporter. Creatine, although naturally synthesized in the human body, can be ingested in the form of supplements and is commonly used by athletes. The purpose of this review was to assess the clinical applications of creatine supplementation on paediatrics. Creatine metabolism disorders have so far been described at the level of two synthetic steps, guanidinoacetate N-methyltransferase (GAMT) and arginine: glycine amidinotransferase (AGAT), and at the level of the creatine transporter 1(CrT1). GAMT and AGAT deficiency respond positively to substitutive treatment with creatine monohydrate whereas in CrT1 defect, it is not able to replenish creatine in the brain with oral creatine supplementation. There are also data concerning the short and long-term therapeutic benefit of creatine supplementation in children and adults with gyrate atrophy (a result of the inborn error of metabolism with ornithine delta- aminotransferase activity), muscular dystrophy (facioscapulohumeral dystrophy, Becker dystrophy, Duchenne dystrophy and sarcoglycan deficient limb girdle muscular dystrophy), McArdle's disease, Huntington's disease and mitochondria-related diseases. Hypoxia and energy related brain pathologies (brain trauma, cerebral ischemia, prematurity) might benefit from Cr supplementation. This review covers also the basics of creatine metabolism and proposed mechanisms of action.
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PMID:Clinical applications of creatine supplementation on paediatrics. 1975 Nov 79

There is an ongoing need for clinically relevant models of perinatal infection and hypoxia-ischemia (HI) in which to test therapeutic interventions for infants with the neurological sequela of prematurity. Ferrets are ideal candidates for modeling the preterm human brain, as they are born lissencephalic and develop gyrencephalic brains postnatally. At birth, ferret brain development is similar to a 13 week human fetus, with postnatal-day (P) 17 kits considered to be equivalent to an infant at 32-36 weeks' gestation. We describe an injury model in the P17 ferret, where lipopolysaccharide administration is followed by bilateral cerebral ischemia, hypoxia, and hyperoxia. This simulates the complex interaction of prolonged inflammation, ischemia, hypoxia, and oxidative stress experienced in a number of neonates who develop brain injury. Injured animals display a range of gross injury severity, with morphological changes in the brain including narrowing of multiple cortical gyri and associated sulci. Injured animals also show slowed reflex development, slower and more variable speed of locomotion in an automated catwalk, and decreased exploration in an open field. This model provides a platform in which to test putative therapies for infants with neonatal encephalopathy associated with inflammation and HI, study mechanisms of injury that affect cortical development, and investigate pathways that provide resilience in unaffected animals.
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PMID:A Ferret Model of Inflammation-sensitized Late Preterm Hypoxic-ischemic Brain Injury. 3181 8