Objective.To study the role of endogenous carbon monoxide (CO) in endotoxin shock. Methods. The changes of CO levels and the effects of zinc protoporphyrin IX (ZnPP),an inhibitor of hemeoxygenase (HO), in endotoxin sh...Objective.To study the role of endogenous carbon monoxide (CO) in endotoxin shock. Methods. The changes of CO levels and the effects of zinc protoporphyrin IX (ZnPP),an inhibitor of hemeoxygenase (HO), in endotoxin shock and the efficacy of hemin,an inducer of HO were investigated. Results.The plasma CO levels were found to be significantly increased during the course of endotoxin shock. Injection of ZnPP was shown to abrogate the endotoxininduced hypotension and metabolic derangements markedly. Administration of hemin to healthy rabbits revealed the hypotension and metabolic derangements similar to the animals given endotoxin. Conclusion.CO is a newly found endogenously produced mediator which may play an important role in the pathogenesis of endotoxin shock.展开更多
Objectives: To test the utility of zinc protoporphyrin to heme ratio (ZnPPH) as an indicator of iron status in premature infants and to evaluate the effect of oral iron supplements on oxidative injury. We hypothesized...Objectives: To test the utility of zinc protoporphyrin to heme ratio (ZnPPH) as an indicator of iron status in premature infants and to evaluate the effect of oral iron supplements on oxidative injury. We hypothesized that iron sulfate supp-lementation would decrease the ZnPPH in preterm infants. Study design: Infants eligible for this prospective study were: hospitalized, 24 to 32 weeks of gestation, 7 to 60 days old, feeding≥70mLkgd, with a ZnPPH ≥the mean for age. Iron dose was determined by the ZnPPH. Iron status and oxidative injury were evaluated at study entry and completion. Concurrent control subjects met entry criteria but were not enrolled and were not treated with iron during the study interval. Statistical evaluation included repeated measures analysis of variance and Z-score conversions. Results: Entry ZnPPH of iron-treated subjects (n = 16) and control subjects (n = 16) were not different. The ZnPPH of iron-treated infants was lower at study end (P < .05) but did not change in control infants. Iron treatment (3 to 12 mgkgday)-was not associated with changes in conventional measures of iron status nor in measures of oxidative injury. Conclusions: Iron sulfate supplementation (3-12 mgkgd) decreases ZnPPH, is tolerated, and is not associated with increased oxidative injury.展开更多
In order to develop a new field of the enzyme design using steroid template and explore the hydrophobic action of enzyme model, we investigated, for the first time, the catalytic properties of steroid-metalloporphyrin...In order to develop a new field of the enzyme design using steroid template and explore the hydrophobic action of enzyme model, we investigated, for the first time, the catalytic properties of steroid-metalloporphyrins towards oxidation of isopropylbenzene. It has been found out that the catalytic activities of metalloporphyrins have been greatly increased because of the presence of the hydrophobic plane of steroids. This fact reveals the展开更多
文摘Objective.To study the role of endogenous carbon monoxide (CO) in endotoxin shock. Methods. The changes of CO levels and the effects of zinc protoporphyrin IX (ZnPP),an inhibitor of hemeoxygenase (HO), in endotoxin shock and the efficacy of hemin,an inducer of HO were investigated. Results.The plasma CO levels were found to be significantly increased during the course of endotoxin shock. Injection of ZnPP was shown to abrogate the endotoxininduced hypotension and metabolic derangements markedly. Administration of hemin to healthy rabbits revealed the hypotension and metabolic derangements similar to the animals given endotoxin. Conclusion.CO is a newly found endogenously produced mediator which may play an important role in the pathogenesis of endotoxin shock.
文摘Objectives: To test the utility of zinc protoporphyrin to heme ratio (ZnPPH) as an indicator of iron status in premature infants and to evaluate the effect of oral iron supplements on oxidative injury. We hypothesized that iron sulfate supp-lementation would decrease the ZnPPH in preterm infants. Study design: Infants eligible for this prospective study were: hospitalized, 24 to 32 weeks of gestation, 7 to 60 days old, feeding≥70mLkgd, with a ZnPPH ≥the mean for age. Iron dose was determined by the ZnPPH. Iron status and oxidative injury were evaluated at study entry and completion. Concurrent control subjects met entry criteria but were not enrolled and were not treated with iron during the study interval. Statistical evaluation included repeated measures analysis of variance and Z-score conversions. Results: Entry ZnPPH of iron-treated subjects (n = 16) and control subjects (n = 16) were not different. The ZnPPH of iron-treated infants was lower at study end (P < .05) but did not change in control infants. Iron treatment (3 to 12 mgkgday)-was not associated with changes in conventional measures of iron status nor in measures of oxidative injury. Conclusions: Iron sulfate supplementation (3-12 mgkgd) decreases ZnPPH, is tolerated, and is not associated with increased oxidative injury.
基金Project supported by the National Natural Science Foundation of China
文摘In order to develop a new field of the enzyme design using steroid template and explore the hydrophobic action of enzyme model, we investigated, for the first time, the catalytic properties of steroid-metalloporphyrins towards oxidation of isopropylbenzene. It has been found out that the catalytic activities of metalloporphyrins have been greatly increased because of the presence of the hydrophobic plane of steroids. This fact reveals the