Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

One hundred forty-nine consecutive patients with tetralogy of Fallot, with or without pulmonary atresia, underwent Blalock-Taussig or Waterston operation for initial palliation. Of these patients, 45 were less than 6 months old, and 63 were less than 1 year old. The type of shunt, and the presence or absence of pulmonary atresia did not have a significant effect (p greater than 0.2) on hospital mortality. Parametric analysis showed a significant effect of age (p = 0.03), the risk of hospital death being 6% at 1 month of age, 4% at 3 months, 3% at 6 months, and 2.5% at 12 months. No late deaths occurred before the age of 3 years. Six patients (4.2% of the hospital survivors) required another operation before they were 3 years old. Severe arm ischemia occurred after a Blalock-Taussig shunt in 1 infant with Down's syndrome.
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PMID:Classic shunting operations as part of two-stage repair for tetralogy of Fallot. 37 53

Of 737 patients with Down syndrome, newborn to 22 years of age, 47 had a history of at least one seizure. Of those, 24 children had seizures with an identifiable etiology, usually related to a common medical complication of Down syndrome: neonatal hypoxia-ischemia, hypoxia from congenital heart disease, or infection. These acute medical illnesses may precipitate seizures in brains already predisposed to hyperexcitability because of abnormal neuronal development. It is recommended that all Down syndrome children with seizures undergo investigations to determine the etiology of the seizure.
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PMID:Seizures in children with Down syndrome: etiology, characteristics and outcome. 182 17

Two patients with Down's syndrome undergoing intracardiac operations had segmental and generalized myoclonic movements postoperatively and eventual brain death. Electroencephalography in 1 patient showed no seizure despite the presence of the myoclonic movements. Computed tomographic scan showed possible cerebellar hemorrhage. Ultrasound showed cerebral edema when the pupils became fixed and dilated. Because known postoperative neurologic complications could not fully explain the clinical course, and the myoclonic movements suggested spinal origin, we considered the possibility of atlantoaxial instability causing spinal cord damage related to perioperative head and neck positioning. Postmortem study on the second patient revealed 50% reduction of the spinal canal with hyperextension and 90-degree external rotation of the head and neck. In contrast, similar maneuvers in 3 infants without Down's syndrome resulted in only mild spinal canal narrowing. Although the myoclonic movements could be explained by spinal cord compression at the atlantoaxial level, the explanation for the eventual brain death is unclear. However, kinking of the vertebral arteries related to the positioning could have caused cerebellar ischemia, hemorrhage, and increased intracranial pressure. We believe that attention to the problem might bring further answers in the future.
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PMID:Perioperative spinal canal narrowing in patients with Down's syndrome. 183 20

In this review the chemistry and formation of oxygen radicals is surveyed. Various physiological protective mechanisms against oxygen radicals as well as the consequence of too much or too little oxygen radicals in diseases is discussed. In this respect attention is given to hypoxia/ischemia, bronchopulmonary dysplasia, retrolental fibroplasia, thalassaemia, Down's syndrome and chronic granulomatous disease. Finally some new developments in pharmacotherapeutic possibilities which might play a role in prevention or amelioration of free radical pathologies are mentioned.
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PMID:[Oxygen radicals: rescue or threat?]. 255 29

The current status of superoxide dismutase (SOD) is that it is an enzyme with diverse ramifications. This review attempts an understanding of SOD as a structural, functional, and biological entity. Accordingly, the review is in three parts. The first part discusses SOD in terms of protein structure, proceeding from primary to secondary and three-dimensional structure for the three forms of SOD: copper/zinc SOD, manganese SOD, and iron SOD. This is the order of structural knowledge of the enzyme. Iron SOD is an enzyme of prokaryotes and some higher plants. Manganese SOD is an enzyme of prokaryotes and eukaryotes. Copper/zinc SOD is an enzyme of eukaryotes and certain prokaryotes. The evolutionary relationships of the three forms of SOD, the status of the copper/zinc SOD gene in prokaryotes, and the cloning and sequencing of SOD genes are discussed. The second part of the review deals with the catalytic mechanism of SOD in the three forms of the enzyme. Structural and mechanistic conclusions from various spectroscopic studies are critically considered. A detailed picture is given of the active site of copper/zinc SOD. The third part is a review of SOD in the general context of oxygen toxicity. After consideration of the question of superoxide toxicity and superoxide pathology, several areas in which SOD has been investigated or used as a tool in a biochemical, pharmacological, or clinical context are discussed, including population genetics; trisomy 21; development and senescence; the nutritional copper, zinc, and manganese status; hemolysis and anemia; oxygen toxicity in the lung and nervous system; inflammation, autoimmune disease and chromosome breakage, ischemia and degenerative changes; radiation damage; and malignancy. A comprehensive picture is given of measurements of SOD activity in disease states, and the question of superoxide-related disease is considered at several points.
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PMID:Aspects of the structure, function, and applications of superoxide dismutase. 331 61

The prevalence of severe dementia in the United States is about 1.3 million cases, of which at least 50 to 60% are of the Alzheimer type. Severe dementia of the Alzheimer type is found rarely in a clearly dominant pattern, although often one or more relatives are affected. Down's syndrome in adults is often associated with Alzheimer changes. The diagnosis is a clinicopathological one; there is a considerable error rate in the clinical diagnosis early in the course of the disease, especially in regard to dementia in depression. The differential diagnosis involves a great many disorders, including multi-infarct dementia, tumors, subdural hematomas, and others. Physiological aspects of Alzheimer's disease include a diffusely slow electroencephalogram, reduced cerebral blood flow, and particular patterns noted on positron emission tomographic scanning. The latter technique has also demonstrated that oxygen extraction is normal in Alzheimer's disease, thus excluding ischemia from possible pathogenetic factors. Morphological changes, that is, the presence of plaques and tangles, are widely distributed in neocortex, paleocortex, and many deep gray areas down through the pontine tegmentum, but largely exclude the basal ganglia, thalamus, and substantia nigra. Numerous plaques without neocortical tangles are found in many demented persons older than 75 years. A severe loss of large neocortical neurons is characteristic of the disease. The chemical nature of the paired helical filaments that make up the neurofibrillary tangle has not yet been ascertained. Neurons are markedly deficient in the basal forebrain nuclei, and this deficiency may account for the severe diminution of choline acetyltransferase and acetylcholine in the neocortex and paleocortex. Muscarinic cholinergic receptors are present in normal amounts. Norepinephrine is reduced in some cases, and somatostatin in most. Substance P is low in severe cases. The etiology of the disorder is unknown and the role of aluminum is disputed. Management of patients with Alzheimer's disease is difficult, and neuroleptics are to be used with great caution because of their side effects. Substrate therapy has not been effective; physostigmine improves memory but is not suitable for general use. Trophic factors, gangliosides, and aluminum chelation are being investigated for use in pharmacological intervention.
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PMID:Senile dementia of the Alzheimer type. 613 75

A collaborative study was performed to determine the different types and mechanisms of intestinal abnormalities during gestation. Cases had to fulfill one or more of the following three criteria: (1) meconium ileus, (2) intestinal stenosis or atresia, and (3) meconium peritonitis. Esophageal atresia, anorectal atresia, and abdominal wall defects were excluded. One hundred two cases were reviewed from the autopsies of 42 induced abortions, 22 stillborns, and the surgical findings in 38 neonates. Meconium ileus was detected mainly during the second trimester (28/38), and was associated with cystic fibrosis (15), fetal blood deglutition (4), infection (6), or multiple-abnormalities (10), in which three chromosomal aberrations were found. Intestinal stenosis or atresia was more commonly detected during the third trimester of gestation (46/56). Sixteen of the 30 duodenal malformations were associated with trisomy 21, whereas in the 26 small intestinal atresias, signs of distress or ischemia were most frequently detected. Only 8 of 25 meconium peritonitis cases were isolated. A total of 20 cystic fibrosis cases could be proved. In this series, functional abnormalities were observed predominantly in the second trimester and associated mainly with cystic fibrosis or amniotic fluid abnormalities. Anatomic lesions were commonly detected later on and associated with ischemic conditions, chromosomal aberrations, and even cystic fibrosis.
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PMID:Meconium ileus and intestinal atresia in fetuses and neonates. 896 29

The major neurodegenerative disorders include Alzheimer's disease, amyotrophic lateral sclerosis, Parkinson's disease, and multiple sclerosis. Although their etiology and pathogenesis are unknown, numerous recent studies suggest that oxygen-derived free radicals play an important role. Furthermore, these reactive oxygen species are probably important in brain ischemia and reperfusion, Down's syndrome, and the mitochondrial encephalopathies. In this review, evidence for oxygen-derived free radicals in the pathogenesis of these disorders is discussed.
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PMID:Reactive oxygen species and the neurodegenerative disorders. 899 53

The pathophysiology of organ system failure in sepsis, in particular the effects of septic shock on the central nervous system, are still incompletely understood. Lipopolysaccharide (LPS) from Gram-negative bacteria affects the permeability of the blood-brain barrier and causes the activation of brain microglia. A growing body of research supports involvement of activated brain microglia in brain pathologies caused by infectious diseases, trauma, tumors, ischemia, Alzheimer's disease, Parkinson's disease, Down's syndrome, multiple sclerosis and AIDS. Those seminal studies that have contributed to the characterization of the in vivo and in vitro effects of LPS on microglia function, mediator generation and receptor expression are presented within a historical perspective. In particular, all those in vitro studies on O2-, H2O2 and NO. generation by either unprimed or primed microglia have been extensively reviewed. The apparent controversial effect of LPS on microglia O2- is discussed. Because treatment modalities for septic shock have not significantly affected the current high mortality, alternative strategies with antioxidants are currently being investigated. Reduction of microglia O2- generation is proposed as a possible complementary strategy to antioxidative therapy for septic shock and CNS pathologies that involve activated microglia.
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PMID:Therapeutic implications of microglia activation by lipopolysaccharide and reactive oxygen species generation in septic shock and central nervous system pathologies: a review. 981

During the past 15 years a variety of inflammatory proteins has been identified in the brains of patients with Alzheimer's disease (AD) postmortem. There is now considerable evidence that in AD the deposition of amyloid-beta (A beta) protein precedes a cascade of events that ultimately leads to a local "brain inflammatory response." Here we reviewed the evidence (i) that inflammatory mechanisms can be a part of the relevant etiological factors for AD in patients with head trauma, ischemia, and Down's syndrome; (ii) that in cerebral A beta disorders the clinical symptoms are determined to a great extent by the site of inflammation; and (iii) that a brain inflammatory response can explain some poorly understood characteristics of the clinical picture, among others the susceptibility of AD patients to delirium. The present data indicate that inflammatory processes in the brain contribute to the etiology, the pathogenesis, and the clinical expression of AD.
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PMID:Inflammation and Alzheimer's disease: relationships between pathogenic mechanisms and clinical expression. 987 71


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