No abstract available.
Animals ; Lipid Peroxides ; Mice* ; Skin*

Using lipid bilayer reconstitution technique, we investigated the oxidation effect of t-butyl hydrogen peroxide (tBHP) on the single channel activity of the sarcoplasmic reticulum (SR) calcium release channels isolated from canine latissimus dorsi muscles. When 0.7% tBHP was added in the cytosolic side, the channel activity became suppressed (n = 7), and it was recovered by changing the solution to the control solution. The suppression was due to the change in the gating mode of the channel: before tBHP the channel opened to four sub-conductance levels, but it opened to only one level after tBHP. These effects by tBHP were different from the previous finding using hydrogen peroxide (H2O2), which may be explained by different oxidation patterns between the two oxidants.
Animal ; Calcium Channels/drug effects* ; Dogs ; Hydrogen Peroxide/pharmacology ; Peroxides/pharmacology* ; Sarcoplasmic Reticulum/metabolism ; Sarcoplasmic Reticulum/drug effects* ; tert-Butylhydroperoxide

OBJECTIVE: The object of this study is to determine whether there is any association between birth to placenta weight ratio and oxidative stress. 34 pregnant women (who gave birth after 36 weeks of pregnancy by cesarean section without labor) were divided into three groups according to their birth to placenta weight ratio. The degree of lipid peroxidation in the placenta and the activity of superoxide dismutase which removes peroxide products were compared in three groups METHODS: In the 34 women who gave birth through cesarean section before labor, we classified the patients to three groups ; the first group (n=13) women whose birth to placenta weight ratio was equal to or above 5.0. The second group (n=14) whose ratio was between 4.3 and 5.0. The third group (n=7) whose ratio was less than 4.3. We measured malondialdehyde (MDA) as a indicative marker of lipid peroxidation through a Thibarbituric Acid (TBA) method, and the activity of superoxide dismutase (SOD) as a antioxidant defense system through a Bioxytech SOD-525 kit (OxisResearch, USA). Data were analyzed statistically using ANOVA test (SPSS for Windows 10.0) and students's t-test. RESULTS: In a group consisting of preeclampsia and FGR, the birth to placenta weight ratio had no significant difference. The mean MDA concentration of group 1 was 7.38+/-6.6 nmole/mg protein, which was significantly lower than both mean of group 2 (17.39+/-12.54 nmole/ mg protein) and group 3 (19.89+/-8.69 nmole/mg protein), There were no significant differences between group 2 and 3. The MDA/SOD ratio of group 1 was 1.01+/-0.97, which was significantly lower than those of group 2 and 3, which were 2.79+/-2.92 and 3.29+/-2.18, respectively. However, there were no significant differences between group 2 and 3. CONCLUSIONS: It is possible to assume that oxidative stress participates in the mechanism of decreased birth to placental weight ratio. Th decreased ratio is probably due to excessive lipid peroxides in placenta. To evaluate the association of birth to placental weight ratio with oxidative stress.
Cesarean Section ; Female ; Humans ; Lipid Peroxidation ; Lipid Peroxides ; Malondialdehyde ; Oxidative Stress ; Parturition ; Placenta ; Pre-Eclampsia ; Pregnancy ; Pregnant Women ; Superoxide Dismutase ; Superoxides

Effects of melatonin on hepatic glutathione-peroxidase (GSH-Px) and glutathione-reductase (GSH-reductase) activities were studied in Sprague-Dawley (SD) rats administered i.p. (10 mg/kg body weight) with melatonin during 15 days. The activity of cytosolic GSH-reductase in the liver was not changed by melatonin. However, melatonin injection increased significantly the activity of liver cytosolic GSH-Px activity compared with those in saline-treated rats. At the same time, plasma GSH-Px was also increased significantly in melatonin-treated rats. Since GSH-Px, a major antioxidative enzyme, removes H-2O-2 and lipid peroxides which are formed during lipid peroxidation from cellular membrane, such elevation of heptatic GSH-Px activity may contribute to the improvement of antioxidative effects under oxidative damage in the liver.
Animals ; Cytosol ; Lipid Peroxidation ; Lipid Peroxides ; Liver ; Melatonin* ; Membranes ; Plasma ; Rats ; Rats, Sprague-Dawley*

The papaya leaf has many biochemical components such as glycoside, proteins, polyphenol, alkaloid, flavonoid, fatty acid, phytosterol, triglyceride, etc. They have the different chemical, physical and biological characters. The fixed material and processing, preparation methods influence strongly to proteins, sugar, polyphenol and flavonoid content and their antioxidation character
Peroxides ; blood

Chronic heart failure is the end stage of heart diseases caused by multiple causes. Myocardial cell injury is the key cause of cardiac function deterioration. Ferroptosis, an iron-dependent programmed death mode, is characterized by iron overload and excessive accumulation of lipid peroxides. Studies have demonstrated that inhibiting ferroptosis has a protective effect on myocardial cells. The theory of "harmful hyperactivity and responding inhibition" is an important rule developed by physicians to explain the generation and restriction of the five elements and the pathological imbalance of the human body, and can guide medication. Correlating with the nature, humans need to rely on the law of responding inhibition to maintain the harmony of five Zang-organs and the steady state of Fu-organs. The pathogenesis of ferroptosis in chronic heart failure highly coincides with the process of failing to "inhibition and hyperactivity becoming harmful". The initial factor of ferroptosis is the deficiency of heart Qi, which results in the inability to maintain the balance of cardiomyocyte redox system. The involvement of the five Zang-organs leads to the loss of distribution of body fluid and blood. As a result, the phlegm turbidity, blood stasis, and water retention in the meridians occur, which are manifested as the accumulation of iron and lipid peroxides, which is the aggravating factor of ferroptosis. The two factors interact with each other, leading to the spiral development and thus aggravating heart failure. According to the traditional Chinese medicine(TCM) pathogenesis of ferroptosis, the authors try to treat the chronic heart failure by stages in accordance with the general principle of restraining excess and alleviating hyperactivity. The early-stage treatment should "nourish heart Qi, regulate the five Zang-organs, so as to restrain excess". The middle-stage treatment should "active blood, resolve phlegm, dispel pathogen, and eliminate turbidity", so as to alleviate hyperactivity. The late-stage treatment should "warm Yang, replenish Qi, active blood, and excrete water". Following the characteristics of pathogenesis, the TCM intervention can reduce iron accumulation and promote the clearance of lipid peroxide, thus inhibiting ferroptosis and improving cardiac function.
Humans ; Ferroptosis ; Lipid Peroxides ; Medicine, Chinese Traditional ; Heart Failure/drug therapy* ; Chronic Disease ; Iron ; Water

This study investigated the clinical effectiveness and safety of sealed bleaching compared to conventional in-office bleaching using a randomized clinical trial of split arch design. Ten participants received a chairside bleaching treatment on the upper anterior teeth, and each side was randomly designated as sealed or control side. A mixture of Brite powder (PacDent, Walnut, USA), 3% hydrogen peroxide and carbamide peroxide (KoolWhite, PacDent, Walnut, USA) were used as bleaching agent. The control side was unwrapped and the experimental side was covered with a linear low density polyethylene (LLDPE) wrap for sealed bleaching. The bleaching gel was light activated for 1 hour. The tooth shades were evaluated before treatment, after treatment, and at one week check up by means of a visual shade (VS) assessment using a value oriented shade guide and a computer assisted shade assessment using a spectrophotometer (SP). The data were analyzed by paired t-test. In the control and sealed groups, the visual shade scores after bleaching treatment and at check up showed statistically significant difference from the preoperative shade scores (p < .05). The shade scores of the sealed group were significantly lighter than the control immediately after bleaching and at the check-up appointment (p < 0.05). Compared to prebleaching status, the DeltaE values at post-bleaching condition were 4.35 +/- 1.38 and 5.08 +/- 1.34 for the control and sealed groups, respectively. The DeltaE values at check up were 3.73 +/- 1.95 and 4.38 +/- 2.08 for the control and sealed groups. DeltaE values were greater for the sealed group both after bleaching (p < .05) and at check up (p < .05). In conclusion, both DeltaE and shade score changes were greater for the sealed bleaching group than the conventional bleaching group, effectively demonstrating the improvement of effectiveness through sealing.
Hydrogen Peroxide ; Juglans ; Light ; Peroxides ; Polyethylene ; Tooth ; Urea

This clinical study evaluated the whitening effect and safety of polymer based-pen type BlancTis Forte (NIBEC) containing 8.3% carbamide peroxide. Twenty volunteers used the BlancTis Forte whitening agent for 2 hours twice a day for 4 weeks. As a control, Whitening Effect Pen (LG) containing 3% hydrogen peroxide was used by 20 volunteers using the same protocol. The change in shade (DeltaE*, color difference) was measured using Shadepilot(TM) (DeguDent) before, during, and after bleaching (2 weeks, 4 weeks, and post-bleaching 4 weeks). A clinical examination for any side effects (tooth hypersensitivity or soft tissue complications) was also performed at each check-up. The following results were obtained. 1. Both the experimental and control groups displayed a noticeable change in shade (DeltaE) of over 2. No significant differences were found between the two groups (p > 0.05), implying that the two agents have a similar whitening effect. 2. The whitening effect was mainly due to changes in a and b values rather than in L value (brightness). The experimental group showed a significantly higher change in b value, thus yellow shade, than the control (p < 0.05). 3. None of the participants complained of tooth hypersensitivity or soft tissue complications, confirming the safety of both whitening agents.
Bleaching Agents ; Hydrogen Peroxide ; Hypersensitivity ; Peroxides ; Polymers ; Tooth ; Urea

OBJECTIVETo examine changes of blood oxidative-antiovidative level in schizophrenic patients and its relationship with clinical symptoms.

METHODSForty-six Chinese patients met DSM-IV (Diagnostic and Statistical Manual of Mental Disorders-IV) criteria for schizophrenia and fifty age- and sex-matched healthy controls were enrolled in the present study. Baseline psychiatric symptom severity was assessed with brief psychiatric rating scale, positive and negative syndrome scale on the blood draw day. Fresh blood samples were collected to measure levels of nitric oxide and lipid peroxide in plasma as well as activities of superoxide dismutase, catalase and glutathione peroxidase in red blood cells by spectrophotometric assays simultaneously.

RESULTSComparison of the biochemical parameters indicated that the level of nitric oxide and lipid peroxide increased in patient group, which represented a positive correlation with positive scale scores; while the activities of three critical enzymes decreased and showed a negative linear correlation.

CONCLUSIONThis study showed that there are dysregulation of free radical metabolism and poor activities of the antioxidant defense systems in schizophrenic patients. Excess free radicals formation may play a critical role in the etiology of schizophrenia. Using antioxidants might be an effective therapeutic approach to partially alleviate or prevent the symptoms of schizophrenia.

Adolescent ; Adult ; Antioxidants ; metabolism ; Female ; Free Radicals ; Humans ; Lipid Peroxides ; metabolism ; Male ; Middle Aged ; Nitric Oxide ; metabolism ; Schizophrenia ; etiology ; metabolism

OBJECTIVETo observe effects of ginsenoside-Rb (G-Rb) on total cholesterol, lipoprotein cholesterol metabolism and anti-oxidation in experimental hyperlipidemia rats.

METHODHyperlipidemia rats were respectively given G-Rb 50, 100, 200 mg x kg(-1) x d(-1) ig for twelve days. Total cholesterol, lipoprotein cholesterol and lipid peroxidation (LPO) contents, prostacycline (PGI2), thromboxane (TXA2), superoxide dismutase (SOD) and blood viscosity were measured. Fat accumulation in liver was also observed.

RESULTTriglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-c) in serum, TXA2 in plasma, LPO in serum and liver, and blood viscosity were decreased significantly. High density lipoprotein cholesterol (HDLc) in serum, PGI2 in plasma and SOD in serum and liver were significantly increased by G-Rb (100, 200 mg x kg(-1)) in experimental hyperlipidemia rats. In addition, G-Rb could decrease TC/HDL-c, LDLc/HDL-c ratio, increase PGI2/TXA2 ratio and inhibit fat accumulation in liver.

CONCLUSIONG-Rb could have anti-arteriosclerosis effect by improving cholesterol and lipoprotein-cholesterol metabolism, suppressing lipid peroxidation, increasing anti-oxidase activity and PGI2/TXA2 ratio.

Animals ; Antioxidants ; pharmacology ; Female ; Ginsenosides ; pharmacology ; Hyperlipidemias ; metabolism ; Lipid Peroxides ; metabolism ; Liver ; metabolism ; Male ; Rats ; Rats, Wistar