Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0243026 (sepsis)
 52,417 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cu,Zn-superoxide dismutase (SOD1) acts as a peroxidase in the presence of H2O2 at high pH (pH > 9). The high pH species of H2O2, HO2-, was previously implicated as the reactive species. However, recent EPR studies of the enzyme performed in the physiological pH range 7.4-7.6 with the spin trap 5,5'-dimethyl-1-pyrolline-N-oxide attributed the intense EPR signal of 5, 5'-dimethyl-1-pyrolline-N-oxide-OH obtained from SOD1 and H2O2 to the peroxidase activity of the enzyme. The present study establishes that this intense signal is obtained only in the presence of bicarbonate. To explore the critical role of HCO3-, a comprehensive EPR investigation of the radical production and redox state of the active site copper was performed. The results indicate that HCO3- competes with other anions for the anion-binding site of SOD1 (Arg141) but does not bind directly to the copper. Structurally different anions that bind to Arg141 did not stimulate, but rather blocked, peroxidase function, ruling out an effect due to mere anion binding. However, the structurally similar anions HSeO3- and HSO3- mimic HCO3- in stimulating peroxidase function. These data suggest that HCO3- bound to Arg141 anchors the neutral H2O2 molecule at the active site copper, enabling its redox cleavage. Thus, SOD1 acquires peroxidase activity at physiological pH only in the presence of HCO3- or structurally similar anions. Alterations in pH that shift the HCO3-/CO2 equilibrium as occur in disease processes such as ischemia, sepsis, or shock would modulate the peroxidase function of SOD1.
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PMID:Bicarbonate is required for the peroxidase function of Cu, Zn-superoxide dismutase at physiological pH. 988 Apr 90

Near-infrared spectroscopy (NIRS) is a non-invasive method for monitoring oxygen availability and utilization by the tissues. In intact skeletal muscle, NIRS allows semi-quantitative measurements of haemoglobin plus myoglobin oxygenation (tissue O2 stores) and the haemoglobin volume. Specialized algorithms allow assessment of the oxidation-reduction (redox) state of the copper moiety (CuA) of mitochondrial cytochrome c oxidase and, with the use of specific tracers, accurate assessment of regional blood flow. NIRS has demonstrated utility for monitoring changes in muscle oxygenation and blood flow during submaximal and maximal exercise and under pathophysiological conditions including cardiovascular disease and sepsis. During work, the extent to which skeletal muscles deoxygenate varies according to the type of muscle, type of exercise and blood flow response. In some instances, a strong concordance is demonstrated between the fall in O2 stores with incremental work and a decrease in CuA oxidation state. Under some pathological conditions, however, the changes in O2 stores and redox state may diverge substantially.
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PMID:Near-infrared spectroscopy for monitoring muscle oxygenation. 1075 98

This is a report of a 54-year-old schizophrenic patient with a 15-year history of ingesting metal objects (pica). He presented with severe anemia (hemoglobin of 3 g/dl and hematocrit of 8.3%) and leukopenia (white blood count of 1,300/mm3). Work-up revealed copper deficiency (copper level of <0.05 microg/ml) and elevated zinc levels (280 microg/ml). The zinc toxicity was produced by the zinc content in the coins ingested by the patient over a period of many years. He was initially treated with -acetylcysteine and sodium bicarbonate followed by intravenous copper sulfate. He was also placed on Adolph's meat tenderizer and pancreatin thrice a day orally to loosen the massive amount of metallic objects including coins in his bowel and allow them to pass out in his feces. He was also continued on oral copper sulfate. His copper levels began to rise and reached a maximum of 0.72 microg/ml, and his zinc level fell to 153 microg/ml. However, as he refused surgery to remove the metal objects from his bowel and continued to ingest more coins, there was continued absorption of zinc, which later overcame the efforts to reduce the zinc level and increase copper levels in his blood. He finally succumbed to sepsis and multiorgan failure. Autopsy revealed a coin mass in the stomach weighing 1,870 grams in addition to a sigmoid volvulus caused by another coin bezoar in the colon.
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PMID:Case report of sideroblastic anemia caused by ingestion of coins. 1142 Dec 92

Electron transfer from iron or copper ions to oxygen is an important example of cellular free radical initiation. Oxygen derived free radicals have been implicated as mediators of cellular injury in several model systems. To evaluate the importance of iron, copper and zinc levels on lipid peroxidation in peritonitis, we measured peritoneum malondialdehyde (MDA) as a marker of lipid peroxidation, zinc, copper, and iron levels during an animal model of intraperitoneal sepsis. Additionally the effects of the free radical scavenger alpha-tocopherol administration was studied. The peritoneum MDA, iron, copper and zinc levels were increased after induction of peritonitis with Escherichia Coli. The treatment with alpha-tocopherol was decreased the peritoneum MDA, iron and copper levels significantly, except the zinc level (p < 0.001, p < 0.001, p < 0.001, respectively). Additionally the alpha-tocopherol treatment for three days prior to injection of E.Coli more decreased MDA, copper and iron levels than that of the treatment with alpha-tocopherol at the time of injection of E. Coli (p < 0.001, p < 0.001, p<0.001, respectively). Our results indicated that copper, iron and zinc had important effects on peroxidation events in E. Coli induced peritonitis, and alpha-tocopherol treatment can improve the oxidant status.
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PMID:Trace element levels in the experimental peritonitis. 1178 75

Activated protein C (APC) is useful in the treatment of sepsis. Ischemia and acidosis, which often accompany sepsis, cause the release of copper from loosely bound sites. We investigated (i) whether physiological concentrations of copper inhibit APC anticoagulant activity and (ii) if any copper-induced APC inhibition is reversible by human serum albumin (HSA) or a high-affinity copper-binding analogue of the human albumin N-terminus, d-Asp-d-Ala-d-His-d-Lys (d-DAHK). APC activity after 30 min of incubation with CuCl2 (10 microM) was decreased 26% below baseline. HSA, both alone and when combined with various ratios of CuCl2, increased APC activity significantly above baseline. d-DAHK alone and 2:1 and 4:1 ratios of d-DAHK:CuCl2 also increased APC activity. APC contained 1.4 microM copper, which helps explain the increased APC activity with HSA and d-DAHK alone. These in vitro results indicate that copper inhibits APC activity and that albumin and d-DAHK reverse the copper-induced APC deactivation.
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PMID:Copper inhibits activated protein C: protective effect of human albumin and an analogue of its high-affinity copper-binding site, d-DAHK. 1182 Jul 75

This article offers a protocol for reducing high case fatality rates from malnutrition. Most child deaths from malnutrition occur in the first few days of treatment. Treatment should involve stabilization followed by rehabilitation. The article describes the treatment procedures for hypoglycemia, hypothermia, dehydration, and missed infections and discusses feeding during the stabilization and rehabilitation phases of treatment. All severely malnourished children have excess body sodium but high intracellular and low plasma levels. Malnourished children have deficiencies of potassium and magnesium that may take 2 weeks to correct. Edema is partly due to deficiencies in potassium and magnesium. A high sodium intake can be corrected by rehydrating with a modified oral rehydration solution and the special starter formula. Family food should be prepared without salt. Magnesium and potassium should be added directly to foods. All severely malnourished children have vitamin and mineral deficiencies. Deficiencies may include vitamin A, zinc, copper, selenium, and folic acid. Multivitamin supplements can correct for micronutrient deficiencies. It is advised that zinc should not be ignored, since it is responsible for repair of intestinal mucosa, halting diarrhea, healing of ulcerated skin lesions, restoration of appetite, improved immune function, and lean tissue synthesis. Iron should not be given until growth starts, infections are controlled, and antioxidant status is improved (usually 1 week after admission). Early introduction of iron poses a risk of enhancing pathogen increases and stimulating production of toxic free radicals. Relapses can be reduced by training parents how to feed their child frequently with energy and nutrient dense foods. The regimen was tested in a South African project and found to reduce mortality from 30% to 20%. After greater hospital attention to treatment of sepsis and hypoglycemia, case fatality declined to 6%.
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PMID:Severe malnutrition in children: high case-fatality rates can be reduced. 1232 Dec 37

Epinephrine is known to be rapidly oxidized during sepsis. Ischemia and acidosis, which often accompany sepsis, are associated with the release of weakly bound cupric ions from plasma proteins. We investigated whether copper promotes oxidation of epinephrine at both physiological and acidic pH and whether D-Asp-D-Ala-D-His-D-Lys (D-DAHK), a human albumin (HSA) N-terminus synthetic peptide with a high affinity for cupric ions, attenuates this oxidation. Epinephrine alone [100 microM] or with CuCl(2) [10 microM], and with CuCl(2) [10 microM] and D-DAHK [20 microM] at pH 7.4, 7.0, 6.5, and 6.0 were incubated for 1h at 37 degrees C. Epinephrine oxidation was measured by the spectrophotometric quantification of its oxidation product, adrenochrome. We found that adrenochrome increased, suggesting copper-induced oxidation of epinephrine. At pH 7.4, 7.0, 6.5, and 6.0, adrenochrome increased by 47%, 53%, 24%, and 6% above baseline, respectively. D-DAHK attenuated the copper-induced oxidation of epinephrine to baseline levels. These in vitro results indicate that copper-induced epinephrine oxidation is greatest at the physiological pH 7.4 as well as in severe acidosis, pH 7.0, and that D-DAHK completely inhibits this oxidation.
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PMID:Copper-induced oxidation of epinephrine: protective effect of D-DAHK, a synthetic analogue of the high affinity copper binding site of human albumin. 1272 20

Endogenous copper can play an important role in postischemic reperfusion injury, a condition associated with endothelial cell activation and increased interleukin 8 (IL-8) production. Excessive endothelial IL-8 secreted during trauma, major surgery, and sepsis may contribute to the development of systemic inflammatory response syndrome (SIRS), adult respiratory distress syndrome (ARDS), and multiple organ failure (MOF). No previous reports have indicated that copper has a direct role in stimulating human endothelial IL-8 secretion. Increased IL-8 in the culture medium of human umbilical vein (HUVEC), lung microvascular, and iliac artery endothelial cells was observed 24 h after the addition of 10 to 50 microM CuCl2 (cupric ions). HUVEC IL-8 induction by copper was higher than by 50 pg/mL tumor necrosis factor-alpha, whereas 50 pg/mL IL-1beta and 1 ng/mL platelet-activating factor did not stimulate IL-8 production or release. HUVEC IL-8 mRNA increased 3 h after CuCl2 stimulation and remained elevated after 24 h, implying sustained transcriptional activation. Copper did not stimulate HUVECs to secrete other cytokines. Cu(II) appeared to be the primary copper ion responsible for the observed increase in IL-8 because a specific high-affinity Cu(II)-binding peptide, d-Asp-d-Ala-d-His-d-Lys (d-DAHK), completely abolished this effect in a dose-dependent manner. These results suggest that Cu(II) may induce endothelial IL-8 by a mechanism independent of known Cu(I) generation of reactive oxygen species. Furthermore, in vivo studies are warranted to determine if copper is involved in the pathogenesis of systemic inflammation and if Cu(II) chelation can reduce this IL-8-induced endothelial inflammatory response.
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PMID:Copper stimulates the synthesis and release of interleukin-8 in human endothelial cells: a possible early role in systemic inflammatory responses. 1286 60

Total parenteral nutrition (TPN)-induced liver injury is a common complication in neonates managed with newborn intensive care. In several of these cases, irreversible and even fatal liver damage may develop, with patients dying of liver failure. In spite of multiple studies over several years, the pathogenesis of TPN-induced liver damage remains poorly understood. Clinical data from 24 neonates with clinical history of receiving TPN who died at Yale-New Haven Children's Hospital and had autopsies performed, were collected by medical record review without knowledge of liver pathology findings. Liver histological sections from these patients were evaluated for multiple parameters without knowledge of the clinical course. Continuous data were analyzed by Wilcoxon signed-rank test and Mann-Whitney test, and dichotomous data by Fisher's exact test; P < 0.05 was considered significant. Different histopathological abnormalities with varying degrees of severity were observed. A progression in the severity of histopathological changes in relation to duration of TPN administration (DTPN) was found. While patients with DTPN of < 2 wk had no fibrosis or only mild degrees of fibrosis, patients with more than 6 wk of DTPN developed moderate-to-severe fibrosis. Similar results were observed for cholestasis and bile duct proliferation. We did not find significant differences for birth weight, gestational age, occurrence of necrotizing enterocolitis, sepsis, or enteral feedings between the group with normal-to-mild liver changes ( n = 16), and the group with moderate-to-severe liver changes ( n = 8). On the other hand, DTPN was significantly different between these two groups ( P = 0.008). Also, patients small for gestational age ( P = 0.003) and patients with bronchopulmonary dysplasia ( P = 0.001) were more commonly seen in the group with moderate-to-severe histopathological findings. Intracellular copper was detected in 12.5% of patients with moderate-to-severe liver changes, and was found in 50% of patients with normal-to-mild liver findings ( P = 0.04). Detection of copper from tissue sections also decreased with DTPN, being observed in 57% of patients with < 2 wk DTPN and in none of the patients with > 12 wk DTPN. Our findings confirm the known significant relationship between the duration of TPN and liver injury. While previously described associations with birth weight, gestational age, enteral feedings, necrotizing enterocolitis, and sepsis were not noted, our study suggests that poor intrauterine growth may be a significant clinical risk factor for TPN-induced liver injury. In addition, our findings suggest that copper may have a protective effect against the development of TPN-induced liver damage.
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PMID:Total parenteral nutrition induced liver pathology: an autopsy series of 24 newborn cases. 1554 67

Protein C (PC) is an essential blood factor in the human blood coagulation cascade. PC can help achieve blood hemostasis in many deadly disease conditions such as sepsis, cancer, HIV, etc.; reduced oxygen transport due to blood agglutination within the body can cause tissue death and organ failure as a result of low oxygen transport. Our goal is to produce large quantities of low cost zymogen PC for the treatment and prevention of blood clotting resulting from many disease states, as well as provide an effective therapy for PC deficiency. Current studies show that Immobilized Metal Affinity Chromatography (IMAC) has high specificity and can be used for difficult separations among homologous proteins at relatively low cost compared to current methods, such as Immunoaffinity Chromatography. Thus, we are investigating the optimization of IMAC for the separation and purification of PC from Cohn fraction IV-I. Molecular interactions within the chromatography column involve many parameters that include: the use and type of chromatographic gel and buffer solution, the pH, temperature, metal ion, chelator, and the sequence and structure of the protein itself. These parameters all influence the protein's interaction with the column. Experimental equilibrium isotherms show that PC has primary and secondary binding characteristics, demonstrating that the interaction is not just a simple process of one protein binding to one metal ion. Understanding the thermodynamics of interfacial interaction between proteins and surface-bound Cu2+ is essential to optimizing IMAC for PC purification, as well as for separation of other proteins in general. Hence we are undertaking theoretical and experimental studies of IDA-Cu/PC adsorption. The differences in structures of PC and other critical homologous blood factors are examined using the protein visualization program Cn3D. A better understanding of the interfacial phenomena will help determine the most effective conditions to achieve our goal.
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PMID:Protein C production: metal ion/protein interfacial interaction in immobilized metal affinity chromatography. 1659 76


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