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)

Carpal tunnel release is the most common hand operation performed in this country. In the absence of specific systemic diseases, the etiology and persistence of pain and dysfunction even after surgical decompression is poorly understood. The focus of this investigation was to investigate the biological factors present within the patients serum that may lead to increased sensitivity to pain. Tissue was collected from patients during surgery. The tissue was homogenized and the homogenate analyzed for the presence of IL-1, IL-6, prostaglandin E series (PGE2). The levels were compared with volunteers that had no evidence of carpal tunnel syndrome or pain. The results showed similar levels of IL-1 (range 42-26 ng/ml) in tissue homogenates, and a significant increase in levels of IL-6 and malionaldehyde bis-(diethyl acetal) in CTS patients in comparison to control tissues. This increase may be associated with oxidative changes occurring as a result of ischemia and reperfusion. Tissue homogenates were also evaluated for PGE2. The CTS tissues showed a five fold elevation in PGE2 compared to control tissues. Levels of PGE2 in CTS tissues were statistically different using a two-tailed student T-test. Increased levels of PGE2 can enhance vascular permeability at the site of injury, and can play an important role in activating adenylate cyclase which increases intracellular cyclic adenosine monophosphate (cAMP). This increase in cAMP levels can inhibit functional responses to other inflammatory stimuli. Increases in PGE2 can also cause sensitization of the nerve endings so that a normal stimulus that would not necessarily cause pain will now be experienced as painful. The results of this study demonstrate that arachidonic acid metabolites PGE2 may be responsible for both the pathological changes and clinical symptomatology in carpal tunnel syndrome.
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PMID:Biochemical and histological analysis of the flexor tenosynovium in patients with carpal tunnel syndrome. 973 66

Preterm labor is the final common pathway after several potential insults to the uterus or fetus. The preterm labor syndrome may be precipitated by several different pathophysiologic events, including intrauterine infection, uterine ischemia, uterine overdistention, hormonal disturbances, and other problems. Intrauterine infections (both clinically evident and subclinical) are associated with increased amniotic fluid concentrations of proinflammatory cytokines, and gestational tissues and the fetus are potential sources of these cytokines. In addition to culture-proven intrauterine infection, there may be an "intrauterine inflammatory response syndrome" that could account for cases of preterm labor in which no infectious organism can be identified. Because the immunologic and endocrinologic systems regulate each other extensively, there is potential for corticotropin-releasing hormone to regulate inflammatory responses and vice versa. The cytokine interleukin 1 stimulates production of corticotropin-releasing hormone, and corticotropin-releasing hormone in turn regulates cytokine production by immune effector cells. Because maternal stress is associated with preterm birth, abnormalities in the regulation of corticotropin-releasing hormone and the production of inflammatory cytokines may be a mechanism that could form the pathophysiologic basis for this association.
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PMID:Immunoendocrinology of preterm labor: the link between corticotropin-releasing hormone and inflammation. 991 28

Intercellular adhesion molecule-1 (ICAM-1) expression was studied with rat transient cerebral ischemic model. The results showed that the expression of ICAM-1 markedly increased after 1 h ischemia following 6 h reperfusion. Laser confocal microscope demonstrated that the FITC quantum on blood vessels after reperfusion was more than 47% compared to that of pure ischemia. MPO activity and light microscope observation showed that leukocytes accumulated in injured tissue 9 h after reperfusion. The local IL-1 content in brain tissue changed with different period of reperfusion time. Our data indicated that after brain ischemia-reperfusion injury ICAM-1 expression was in time-dependent increase, the local IL-1 secretion might up regulate the ICAM-1 expression, there were large amount of leukocytes accumulated in surrounding tissue, the increase of ICAM-1 expression was the prerequisite for leukocyte adhesion and migration.
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PMID:[The study of ICAM-1 expression after brain ischemia-reperfusion injury in rats]. 1007 95

There is a large body of evidence that the liver microcirculation has to be considered as a major target in hepatic ischemia/reperfusion injury. The nature of microvascular injury, which precedes manifestation of hepatic parenchymal tissue damage, includes both hypoxia due to lack of microvascular perfusion (i.e. no-reflow), and a reperfusion-associated inflammatory response, which includes the activation and dysfunction of leukocytes and Kupffer cells (the reflow paradox). No-reflow in sinusoids is thought to be caused by endothelial cell swelling and intravascular hemoconcentration, and involves also a deterioration of the balance between ET and NO. The reflow paradox is associated with: (i) the release and action of proinflammatory cytokines (TNF-alpha, IL-1) and oxygen radicals; (ii) the up-regulation of endothelial and leukocytic adhesion molecules (selectins, beta-integrins, ICAM-1); and (iii) the interaction of leukocytes with the endothelial lining of the hepatic microvasculature.
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PMID:Role of microcirculation in hepatic ischemia/reperfusion injury. 1043 6

In order to investigate locally produced mediators during the process of organ storage in liver transplantation, we collected the liver preservation solution effluent of 15 transplanted livers and compared it with serum samples taken preoperatively from donor and recipient, as well as 60 min after reperfusion. The mean ischemia time +/- SEM was 10 h 10 min +/- 53 min. Mean concentrations in University of Wisconsin preservation solution effluent were: interleukin-(IL-)1beta 154 +/- 77 pg/ml; IL-1 receptor antagonist (IL-1 ra) 1281 +/- 309 pg/ml; IL-6 412 +/- 90 pg/ml; and for tumor necrosis factor-(TNF-)alpha 74 +/- 21 pg/ml. Cytokine levels in the donors were lower than those detected in the effluent. All measured cytokines showed higher concentrations in the effluent compared to those of the recipient prior to the operation. With respect to a comparison of donor and recipient values, no correlation is evident. Likewise, the ischemic time does not correlate with effluent values. Further development of liver preservation concepts requires information about the state of the graft before reperfusion. Data on cytokine liberation may serve as a helpful tool for the further development of preservation concepts because they enable an estimation of cell activation during preservation.
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PMID:Local liberation of cytokines during liver preservation. 1046 Aug 71

Depression represents a major public health problem. It is estimated that 13-20% of the population has some depressive symptoms at any given time and about 5% of the population is assumed to suffer from major depression. Known pathological processes include ischemia, neoplasia, necrosis, apoptosis, infection, and inflammation. Of those, inflammation is the most compatible with the waxing and waning course of depression, and could explain the biology of this disorder that has a fluctuating course with severe episodes that can be followed by partial or complete remission. Over the years a body of evidence has been accumulated suggesting that major depression is associated with dysfunction of inflammatory mediators. Major depression commonly co-occurs with ischemic heart disease and decreased bone mineral density. Depressive symptoms are known to have a negative impact on cardiovascular prognosis, increasing the mortality rate of coronary artery disease. Several lines of evidence indicate that brain cytokines, principally interleukin-1beta (IL-1beta) and IL-1 receptor antagonist may have a role in the biology of major depression, and that they might additionally be involved in the pathophysiology and somatic consequences of depression as well as in the effects of antidepressant treatment. A particularly unique and novel aspect of the studies and views discussed here is their potential to lead to interventions which may reduce the morbidity and mortality risks for osteoporosis, cardiovascular disease, and behavioral symptoms in patients with major depression. We also discuss the emerging concept of peripheral and central cytokine compartments: their integration and differential regulation is a key element for the optimal functioning of the immune and nervous systems.
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PMID:The role of inflammatory mediators in the biology of major depression: central nervous system cytokines modulate the biological substrate of depressive symptoms, regulate stress-responsive systems, and contribute to neurotoxicity and neuroprotection. 1048 47

The proinflammatory cytokines IL-1 alpha, IL-1 beta, IL-6, and TNF-alpha are produced within the CNS, and, similar to the periphery, they have pleotrophic and overlapping functions. We have shown previously that TNF-alpha increases neuronal survival to a toxic influx of calcium mediated through neuronal N-methyl-d -aspartic acid (NMDA) glutamate-gated ion channels. This process, termed excitotoxicity, is a major contributor to neuronal death following ischemia or stroke. Neuroprotection by this cytokine requires both activation of the p55/TNF receptor type I and the release of TNF-alpha from neurons, and it is inhibited by the plant alkaloid nicotine. Here, we report that other inflammatory cytokines (IL-1 alpha, IL-1 beta, and IL-6) are also neuroprotective to excessive NMDA challenge in our system. Neuroprotection provided by IL-1 is distinct from TNF-alpha because it is inhibited by IL-1 receptor antagonist; it is not antagonized by nicotine, but it is inhibited by a neutralizing Ab to nerve growth factor (NGF). Similar to IL-1, IL-6-mediated neuroprotection is also antagonized by pretreatment with IL-1 receptor antagonist and it is not affected by nicotine. However, neutralizing anti-NGF only partially blocks IL-6-mediated protection. These studies support an important role for distinct but overlapping neuroprotective cytokine effects in the CNS.
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PMID:Inflammatory cytokines IL-1 alpha, IL-1 beta, IL-6, and TNF-alpha impart neuroprotection to an excitotoxin through distinct pathways. 1049 Sep 98

Interleukin-1beta (IL-1beta) is expressed after cerebral ischemia and blocking its action reduces subsequent ischemic brain injury. However, the mechanisms by which IL-1beta affects ischemic brain are not understood. To investigate the role of IL- 1beta in regulation of tumor necrosis factor-alpha (TNF-alpha) and intercellular adhesion molecule-1 (ICAM-1) during focal cerebral ischemia, the authors studied mutant mice deficient in the IL-1 converting enzyme (ICE) gene (ICE knockout [KO] mice). Ninety-four adult male ICE KO and wild-type mice underwent 3, 6, 12, and 24 hours of permanent middle cerebral artery occlusion using the suture method. Expression of TNF-alpha and ICAM-1 protein in ischemic brain was examined using immunohistochemistry and Western blot analysis. Neither ICE KO nor wild-type mice had significant differences in CBF and body temperature measurements during the ischemic procedure. TNF-alpha expression increased in the ipsilateral hemisphere after 3 hours of occlusion, peaked at 12 hours and decreased at 24 hours of ischemia in both ICE KO and wild-type mice. ICAM-1 immunohistochemistry showed that the number of ICAM-1-positive vessels in the ischemic hemisphere was reduced in ICE KO mice (P < .05). Western blot analysis showed that ICAM-1 protein expression was significantly attenuated in the ipsilateral hemisphere in the ICE KO mice, which paralleled the immunohistochemistry results. The authors' results indicate that TNF-alpha expression is increased in both ICE KO and wild-type mice suggesting that TNF-alpha expression is not related to or upregulated by IL-1beta . ICAM-1 expression is significantly reduced in the ICE KO mice suggesting that IL-1beta plays an important role in the upregulation of adhesion molecules during focal cerebral ischemia.
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PMID:Expression of tumor necrosis factor-alpha and intercellular adhesion molecule-1 after focal cerebral ischemia in interleukin-1beta converting enzyme deficient mice. 1053 35

IL-1 and TNF-alpha are known to be pleiotropic cytokines associated with various inflammatory conditions such as small intestinal injury after ischemia-reperfusion. FR167653 has been characterized as a potent suppressant of IL-1 and TNF-alpha production. The effect of FR167653 on intestinal reperfusion injury was investigated in a warm ischemia model of the canine gut. Sixteen mongrel dogs were divided into two groups: a control group and a FR group to which FR167653 was administered. Both the superior mesenteric artery and vein were clamped for 2 hr. Arterial pH, hepatic venous hemoglobin oxygen saturation, intramucosal pH, and the survival rate were well maintained in the FR group in comparison with the control group after reperfusion. FR167653 inhibited the expression of IL-1beta mRNA. Histologically, ischemia-reperfusion injury was more severe in the control group than the FR group. This study suggests that FR167653 inhibits proinflammatory cytokines and ameliorates ischemia-reperfusion injury of the small intestine.
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PMID:Effect of FR167653 on small bowel ischemia-reperfusion injury in dogs. 1057 84

In vivo administration of low doses of lipopolysaccharide (LPS) to rodents can protect these animals from subsequently administrated, usually lethal doses of endotoxin or LPS. In this study we tested the effects of LPS pretreatment on ischemia/reperfusion injury in the kidney. Male C57/B1 mice were pretreated with different doses of LPS or phosphate-buffered saline on days -4 and -3. The right kidney was removed, and the vessels of the left kidney were clamped for 30 or 45 minutes on day 0. Creatinine levels and survival of animals were monitored. To test the involvement of cytokines, additional animals were harvested before ("time 0") and 15 minutes, 1, 2, 8, and 16 hours after reperfusion for histology, immunohistochemistry, terminal deoxynucleotidyltransferase-mediated UTP end-labeling assay, and reverse transcriptase-polymerase chain reaction analysis (including tumor necrosis factor (TNF)-alpha, interleukin (IL)-1, IL-6, inducible nitric oxide synthase (iNOS), and interferon (IFN)-gamma messenger RNA (mRNA)). In controls, renal ischemia of 30 minutes was nonlethal, whereas 73% of the animals died within 48 +/- 18 hours, after 45 minutes of ischemia. All different doses of LPS protected the animals from lethal renal ischemia/reperfusion injury. Starting at similar levels, serum creatinine increased significantly in controls but not in LPS-pretreated animals over time. As early as 2 hours after reperfusion, tubular cell damage was significantly more pronounced in controls than in LPS-treated mice. In controls, tubules deteriorated progressively until 8 hours of reperfusion. At this time, more than 50% of tubular cells were destroyed. This destruction was accompanied by a pronounced leukocytic infiltration, predominantly by macrophages. In contrast, LPS pretreatment prevented the destruction of kidney tissue and infiltration by leukocytes. The terminal deoxynucleotidyltransferase-mediated UTP end-labeling assay revealed significantly more apoptotic cells in controls compared with LPS-pretreated animals. IL-1, IFN-gamma, and iNOS mRNA expression did not differ between the groups throughout the time points examined. However, the expression of TNF-alpha mRNA was significantly increased at 2 hours and IL-6 mRNA was significantly down-regulated before ischemia and shortly after reperfusion in the LPS-pretreated kidneys. Therefore, we found that sublethal doses of LPS induced cross-tolerance to renal ischemia/reperfusion injury. Our data suggest that increased TNF-alpha and reduced IL-6 mRNA expression might be responsible. However, more studies are needed to decipher the exact mechanism.
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PMID:Lipopolysaccharide pretreatment protects from renal ischemia/reperfusion injury : possible connection to an interleukin-6-dependent pathway. 1062 77


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