Effects of dental resin metabolites on estrogenic activity in vitro

Three monomers (Bis-GMA, UDMA, and TEGDMA) and five polymerization initiators (CQ, BPO, DMPT, DMAEMA, and ATU) commonly used in dental composite resins were tested for estrogenic activity using a reporter gene assay (yeast two-hybrid system) in vitro, and compared with bisphenol-A (BPA). Estrogenic activity was indicated by agonist and antagonist activity, with (+S9) and without (-S9) metabolic activation using rat liver cells. No estrogenic agonist activity was seen for each monomer and polymerization initiator in either the -S9 and +S9 tests in the concentration ranges examined in this study. On the other hand, estrogen antagonist activity was found with BPO and DMPT. BPO showed antagonist activity at a concentration of approximately 1800 nM with the -S9 test, but not with the +S9 test. With DMPT, antagonist activity was not seen with the -S9 test, but it was seen at a concentration of approximately 610 nM using the +S9 test. With BPA, the +S9 test indicated antagonist activity at a concentration of approximately 780 nM. The estrogen antagonist activities of DMPT and BPA appeared to be similar. CQ, DMAEMA, ATU, and the three monomers did not show antagonist activity as demonstrated by the -S9 or +S9 tests within the concentration range tested in this study.

Further study on the photochemistry of non-ortho substituted PCBs by UV irradiation in alkaline 2-propanol

The photochemical behaviors of six non-ortho substituted PCB congeners, i.e., 3,4-DiCB, 3,5-DiCB, 3,3',5-TriCB, 3,4,5-TriCB, 3,3',4,5-TetraCB, and 3,4,4',5-TetraCB, irradiated at 254 nm in alkaline 2-propanol were investigated. Besides the determination of the photodechlorination pathways of these compounds, the presence of photorearrangement was observed in the case of 3, 4-DiCB with its products being identified. The results indicate that dechlorination is much more important than rearrangement during the process of PCB photolysis.

Scavenging effect of nicorandil on free radicals and lipid peroxide in streptozotocin-induced diabetic rats

Free radicals and lipid peroxide (LPO), easily formed in the diabetic state, play an important role in the development of diabetic complications. Potentially, nicorandil may reduce the production of free radicals and LPO in various organs. In fact, increased LPO levels in the serum, kidney, and cardiac muscle of diabetic (DM) rats were reduced by nicorandil treatment (N treatment). Xanthine oxidase (XOD), which produces free radicals, was decreased in the liver and increased in the kidney of DM rats compared with control rats, and these changes were prevented by N treatment. The concentration of Cu, Zn-superoxide dismutase (SOD) decreased in the cardiac muscle and increased in the kidney of DM rats, and these changes returned to normal after N treatment. The decreased concentration of Mn-SOD in the liver, kidney, and cardiac muscle from DM rats was also reversed by N treatment. The changes in catalase and glutathione peroxidase (GSH-PX) activities in DM rats were not improved effectively by N treatment. Another K-adenosine triphosphate (K-ATP) channel opener, tilisolol hydrochloride, had an effect similar to that of nicorandil. The effects of nicorandil and tilisolol were studied only in DM rats. These data imply that N treatment, as an antioxidative therapy, may be beneficial in preventing diabetic complications due to lipoperoxidation and free radicals in DM rats.

Lipid peroxidation levels in rat cardiac muscle are affected by age and thyroid status

Free radicals, hydroxyperoxides and H(2)O(2) are all known to damage cell components. This study was designed to compare the concentrations of hydroxyperoxide and free radical scavengers in the cardiac muscles of old rats in the hyper- or hypothyroid condition, to determine whether rates of peroxidation would differ with age, thyroid status, or both. Rats were rendered hyper- or hypothyroid by administration of l-thyroxine or methimazole for 4 weeks. Among the old rats, the lipid peroxide (LPO) concentrations, measured as thiobarbituric acid (TBA) reactants, were significantly greater in the hyperthyroid than in the euthyroid state and the LPO concentrations measured as TBA+Fe(3+) reactants, which may be precursors of LPO, were significantly greater in the hyperthyroid state, whereas in young rats, the LPO concentrations measured by TBA or TBA+Fe(3+) methods did not differ significantly in the hyperthyroid state. In the euthyroid state, the concentration of LPO measured as TBA+Fe(3+) reactants was significantly reduced with age. Xanthine oxidase (XOD) activity also was markedly increased with age, being more pronounced in the hyperthyroid than in the euthyroid state. The Mn and Cu/Zn superoxide dismutase activities were greater in the hyperthyroid than in the euthyroid state. Glutathione peroxidase activity decreased with age in the euthyroid and, particularly, in the hyperthyroid state. Catalase activity was not affected in the old rats. Concentrations of alpha-tocopherol in the old rats were high in the hyperthyroid state and low in the hypothyroid state, whereas the levels of beta- and gamma-tocopherols in these rats were unchanged in both conditions as compared with the euthyroid state findings. Data suggest that the site of free radical generation differs in older rats, with additional shifts in the location of intracellular lipid peroxidation being noted during hyperthyroidism. Thus, as rats age, the reduction of the free radical scavenger system and the increase in LPO and XOD activities might induce myocardial dysfunction.

[The role of discharge coordination nurses in a university hospital--changes in the role with timing of the discharge request]

We studied the role of discharge assisting nurses who coordinate discharge planning (DP). The requests for DP were ordered at different periods during the admission. The periods were mainly divided into three phases in which the DP was ordered from the wards, which were type 1: just before discharge, type 2: after the decision to discharge, and type 3: between admission and the decision to discharge. We analyzed 8 cases, DP ordered in the type 3 phase provided the most satisfactory outcome for patients' home lives, since the nurse, other medical staff and patients had sufficient time to prepare and provide the needed services.

CONCLUSION

It was clarified that type 3 provided the best outcome of discharge planning.

[Actual situations and problems of patients receiving home IVH--trial use of an assessment chart for outpatients]

In order to improve the quality of life (QOL) and continue nursing, we used an assessment chart to investigate the actual situations and problems of the patients receiving home intravenous hyperalimentation (IVH). From January, 1997 to June, 1999, we investigated 20 patients with home IVH. To 7 patients among them, we asked questions using Kurihara's assessment chart for QOL, plus our original questions concerning IVH. The mean age of the patients was 61 years old, and 19 of them had advanced cancers. Forty percent of the patients maintained the IVH all by themselves and 10% of the patients needed the support of their family. The remaining 50% of the patients left all to their family. There were 9 incidents of trouble during the maintenance of the IVH. Almost all patients from whom informed consent had been received were satisfied with the home IVH. On the contrary, all patients who had not given informed consent were not satisfied with the home IVH. According to the results of the assessment chart, even if the total points were low, the points for the IVH were high in the patients had given informed consent. The main reason for lower QOL was pain. The points for the families were lower than those for the patients. They sometimes complained of uneasiness and dissatisfaction with the support they received. We conclude that therapies to improve symptoms and mental state are necessary to satisfy the patients, and that it is important to support not only the patients but also their families.

Serum concentrations of carotenoids, alpha-tocopherol, fatty acids, and lipid peroxides among Japanese in Japan, and Japanese and Caucasians in the US

Serum concentrations of carotenoids, alpha-tocopherol, fatty acids, and thiobarbituric acid-reactive substances (TBARS) were measured in 217 Japanese residents of Japan, and in 99 Japanese and 100 Caucasian residents of the US, aged from 50 y to 74 y. In females, serum values of carotenoids such as beta-carotene (BC) and zeaxanthin & lutein (ZL) were highest among Japanese in Japan, followed by Japanese in the US and Caucasians in the US. In males, these values, except for serum BC values, were also highest among Japanese in Japan. Moreover, serum values of n-3 polyunsaturated fatty acids (n-3PUFAs) such as eicosapentaenoic acid and docosahexaenoic acid were significantly higher among Japanese in Japan than among Japanese and Caucasians in the US in both sexes. In contrast, serum values of n-6 polyunsaturated fatty acids such as linoleic acid and arachidonic acid were lowest among Japanese in Japan. For women, serum levels of n-9 unsaturated fatty acids were lowest among Japanese living in Japan. Serum TBARS values were highest among Japanese in Japan, followed by Japanese in the US and Caucasians in the US. A significant positive correlation was observed between serum values of TBARS and n-3 PUFAs among Japanese both in Japan and in the US. Serum TBARS values showed a significant inverse relationship with the serum values of BC and ZL among Japanese in Japan and with those of BC among Japanese in the US. These relationships were not always observed among Caucasians in the US. The results of this study suggest that the high TBARS values among Japanese in Japan may depend in part on lipid peroxidation induced in vitro by n-3PUFAs, while high reduction of lipid peroxidation could be expected among Japanese in Japan with high antioxidants such as BC and ZL. In conclusion, serum levels of nonprovitamin A carotenoids such as ZL may be a useful intake marker of vegetables. Dietary intakes of dark green vegetables and fish rich in n-3PUFAs might be more important in the prevention of some sites of cancer and of ischemic heart disease.

Changes in superoxide dismutase activities and concentrations and myeloperoxidase activities in leukocytes from patients with diabetes mellitus

To investigate whether the two free-radical scavengers, Cu, Zn- and Mn-superoxide dismutase (SOD), are changed in leukocytes of diabetic patients, and the alteration of these enzymes correlates with the diabetic state, we measured the activity and concentration of these enzymes in leukocytes from diabetic patients. Both Cu, Zn-SOD and Mn-SOD activities in neutrophils and lymphocytes were significantly lower in patients with non-insulin-dependent diabetes mellitus than in healthy controls. The concentrations of these enzymes in leukocytes from diabetic patients, however, did not differ from those in controls. Cu, Zn-SOD and Mn-SOD activities in neutrophils inversely correlated with HbA(1c) concentrations. Myeloperoxidase activity in leukocytes was significantly reduced in NIDDM patients. These findings suggest that changes in these enzymes may affect the susceptibility to infection and immunocompetence of patients with diabetes.

Contribution of serum albumin to the transport of orally administered L-tryptophan into liver of rats with L-tryptophan depletion

The role of serum albumin in the transport of orally administered L-tryptophan (Trp) into rat tissues was examined using analbuminemic and Sprague-Dawley (SD) rats with and without alpha-methyl-DL-tryptophan (AMT)-induced Trp depletion. Trp was orally administered to rats 16 h after AMT or 0.85% NaCl administration, when liver tryptophan 2,3-dioxygenase and protein synthetic activities in AMT-treated rats were similar to those of 0.85% NaCl-treated rats. After oral Trp administration, regardless of the presence or absence of Trp depletion, free serum Trp concentrations were similar in the analbuminemic and SD rats, while total serum Trp concentrations were lower in analbuminemic rats than in SD rats. Although liver, brain, and muscle Trp concentrations after oral Trp administration under Trp depletion were lower in analbuminemic rats than in SD rats, the ratio of the liver Trp concentration in analbuminemic rats to that in SD rats was smaller than that of the brain or muscle Trp concentration. These results suggest that variations in serum albumin levels could affect the transport of orally administered Trp into the liver of rats with Trp depletion.

Effects of thyroid hormone on the sorbitol pathway in streptozotocin-induced diabetic rats

Sorbitol accumulation plays an important role in diabetic complications involving the kidney, nerves, retina, lens and cardiac muscle. To investigate the influence of thyroid hormone on the sorbitol pathway, we studied the effects of thyroid hormone on polyol metabolism in normal and diabetic rats. Rats were divided into three groups: controls, streptozotocin (STZ)-induced diabetic euthyroid rats (DM) and STZ-induced diabetic hyperthyroid (thyroxine-injected) rats (DM+HT). The sorbitol (Sor) concentrations in the kidney, liver and sciatic nerve (2.53+/-0.74, 0.97+/-0.16 and 24.0+/-5.1 nmol/mg protein, respectively) of the DM rats were significantly higher than those (1.48+/-0.31, 0.58+/-0.13 and 3. 1+/-0.6 nmol/mg protein) of the control rats. The Sor concentrations in the kidney and sciatic nerve of the DM+HT rats (1.26+/-0.29 and 9. 40+/-1.2 nmol/mg protein) were significantly lower than those in the DM rats. These values were reduced in the liver, unchanged in the kidney, and increased in the sciatic nerve from the hyperthyroid rats without diabetes. Thyroid hormone reduced the aldose reductase (AR) activities in the kidney, liver and sciatic nerve of the DM rats, and similarly reduced AR in the kidney and liver, but not in the sciatic nerve, of the non-diabetic rats. The sorbitol dehydrogenase (SDH) activities were decreased by thyroid hormone in the kidney and liver but not the sciatic nerve of DM rats. In the non-diabetic rats, this enzyme activity was decreased in liver, but not in kidney or sciatic nerve. A positive correlation between the Sor concentration and AR activity was observed in the kidney and liver but not in the sciatic nerve from control, DM and DM+HT rats. A negative correlation was observed between the Sor concentration and SDH activities in the same organs. These data suggest that thyroid hormone affects the sorbitol pathway, but the detailed mechanism whereby this hormone reduces the sorbitol content (especially in diabetic rats) remains to be clarified.

Reduction of activity, but no decrease in concentration, of erythrocyte Cu,Zn-superoxide dismutase by hyperglycaemia in diabetic patients

Cu,Zn-superoxide dismutase(SOD) activity in erythrocytes is affected by various diseases, including diabetes mellitus (DM). We investigated changes in the Cu,Zn-SOD activity compared to changes in the Cu,Zn-SOD concentration in erythrocytes obtained from patients with Type 2 (non-insulin-dependent) diabetes mellitus. Cu,Zn-SOD activity in erythrocytes was significantly lower in Type 2 DM patients than in healthy non-diabetic subjects. The activity correlated negatively with HbA1c, but not with other indicators of metabolic control, such as fasting blood glucose or plasma cholesterol or triglyceride. However, there was no statistically significant difference in erythrocyte concentration of Cu,Zn-SOD between diabetic and control samples. Concentration did not correlate with enzymatic activity or HbA1c. These findings indicate that the inactivation of Cu,Zn-SOD activity in erythrocytes of Type 2 DM patients by hyperglycaemia may be slow, because there is a negative correlation between the enzyme activities and HbA1c levels, but not fasting blood glucose levels. This is consistent with glycosylation of the active site of Cu,Zn-SOD, without any effect of hyperglycaemia on the concentration of Cu,Zn-SOD.

Improved fluorometric enzymatic sorbitol assay in human blood

Samples for use in the fluorometric enzymatic assay of sorbitol in erythrocytes are normally prepared using HClO4 and K2CO3. We have replaced these reagents with NaOH and ZnSO4. Human whole blood, erythrocyte and plasma samples prepared with NaOH and ZnSO4 are colorless and clear, while erythrocyte samples prepared with HClO4 and K2CO3 are a pale yellow-brown color. The sorbitol dehydrogenase reaction in the supernatant of the mixture of NaOH and ZnSO4 is inhibited, but ethylenediaminetetraacetate completely eliminates this effect. The sorbitol assay in erythrocytes prepared with NaOH and ZnSO4 shows higher sensitivity and reproducibility than did that with HClO4 and K2CO3. Recovery of sorbitol added to erythrocytes is similar in both assay methods. Concentrations of whole blood and erythrocyte sorbitol assayed by the present method are significantly higher in diabetics than in normals. Poorly controlled diabetics had higher whole blood and erythrocyte sorbitol than well-controlled diabetics. Whole blood sorbitol concentrations differed more between diabetic and normal subjects than did erythrocyte sorbitol concentrations.

Changes in free radical scavengers and lipid peroxide in thyroid glands of various thyroid disorders

To clarify whether the changes of free radicals and its scavengers are induced by thyroid disorders, we measured levels of free radical scavengers and checked O2 radical generating systems in the human thyroid gland. Thyroid specimens from patients with Graves' disease, follicular adenoma, and papillary and follicular carcinomas contained significantly higher concentrations of xanthine oxidase (XOD) and gluthathione peroxidase (GSH-PX), compared to those in the normal thyroid tissue. Catalase concentration was significantly lower in thyroid specimens from patients with Graves' disease and significantly lower in thyroid specimens from patients with follicular adenoma, compared to those in the normal thyroid tissue. Cu/Zn superoxide dismutase (Cu/Zn SOD) concentration was significantly lower in the specimens from follicular adenoma and papillary carcinoma and Mn SOD concentration was significantly higher in the specimens from papillary carcinoma than those in the normal thyroid tissue. The lipid peroxide concentration, expressed as malondialdehyde (MDA) concentration, was significantly higher in the specimens from papillary carcinoma than those in the normal thyroid tissue. These findings suggest that the levels of free radicals are increased and are scavenged and catalyzed in the thyroid of Graves' disease, whereas free radicals and lipid peroxide are not completely scavenged in papillary carcinoma tissues, suggesting that these substances affect some role in cell function of thyroid tumors.

Role of the prosthetic groups of NADPH-cytochrome P450 reductase in 3-hydroxyanthranilamide-catalyzed, NADPH-dependent superoxide anion production

The role of the prosthetic groups (FAD and FMN) of NADPH-cytochrome P450 reductase (P450 reductase)in 3-hydroxyanthranilamide (3-OH An.Amide)-catalyzed, NADPH-dependent superoxide anion (O2-) production via the reductase was examined using the native and FMN-depleted preparations of P450 reductase which was partially purified from rat liver microsomes. NADPH-dependent O2-production by the FMN-depleted preparation was about 10% of that by the native preparation. 3-OH An. Amide-catalyzed, NADPH-dependent O2-production by the FMN-depleted preparation was less than 10% of that by the native preparation. FMN supplementation returned O2-production to near normal. We observed the same results for NADPH oxidation and hydrogen peroxide formation. O2-production, NADPH oxidation, and hydrogen peroxide formation were inhibited by native superoxide dismutase (SOD), but not by boiled, denatured SOD. These results indicate that the prosthetic groups, especially FMN, of P450 reductase play a critical role in 3-OH An.Amide-catalyzed, NADPH-dependent O2-production via the reductase.

Pharmacokinetics and polymorphic oxidation of dextromethorphan in a Japanese population

The plasma concentration and cumulative urinary excretion over 34 h of dextromethorphan, free and conjugated dextrorphan, and 3-hydroxymorphinan were determined in seven healthy Japanese subjects after oral administration of 30 mg dextromethorphan hydrobromide. Conjugated metabolites were extensively present, whereas no detectable dextromethorphan or free metabolites were observed in the plasma of any subject. On average, 72% of the dose was excreted in urine within 34 h. This was detected mainly as conjugated metabolites with only slight traces of dextromethorphan and free metabolites. From the time-courses of the metabolic ratio (the ratio of urinary output of dextromethorphan to dextrorphan), the metabolic ratios seemed to become constant 7.5 h after oral administration. Phenotyping was performed using metabolic ratios in 75 unrelated healthy Japanese subjects (43 males and 32 females). The logarithmic metabolic ratio was bimodally distributed and one subject (1.3%) was identified as a poor metabolizer.

[Studies on the behavior of lipid peroxide in reperfusion induced arrhythmia]

Lipid peroxidation of the cell membrane is one of the most important factors of reperfusion induced arrhythmia (RIA). To determine the role of lipid peroxidation in RIA, lipid peroxide (LPO) and superoxide dismutase (Total, Mn-SOD) were examined in this experiment. Thirty-four male Donryu strain rats (250-350 g body weight) were studied. After left thoracotomy and 5-minute ligature of LAD coronary artery, reperfusion was done under artificial ventilation with room air. The electrocardiogram (ECG) was recorded via standard limb leads. Twenty-four rats were divided into 5 groups and the heart tissue and blood samples were collected 1. preligature 2. after 1-minute ligature 3. after 4-minute ligature 4. 1-minute after declamping and 5. 10-minute after declamping. To examine the correlation between LPO and duration of RIA, samples from another 10 rats were collected as soon as RIA disappeared. LPO, SOD, CPK, and MDH (malate dehydrogenase) were measured in all samples. The total SOD level in heart tissue decreased after reperfusion (p less than 0.05). The heart tissue LPO (t-LPO) decreased after ligature (p less than 0.05), but each value in 2. to 5. was lower than 1., and no increase was found after reperfusion. A negative correlation of R = 0.87 (p less than 0.01) was found between t-LPO and RIA duration, but a positive correlation of R = 0.79 (p less than 0.01) was found between t-LPO and CPK. Moreover, the LPO level was lower in the RIA occurrence group than in the non-occurrence group (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

[Detection methods of free radical related substances and the system for their elimination]

Lipid peroxide and SOD were selected as free radical related substances and system for their elimination, and detection was evaluated. NADPH-Cytochrome c reductase-Neotetrazolium (NT) method (Mic-NT method) and Xanthine oxidase-Nitrotetrazolium Blue method (XOD-NTB method) are current detection methods of SOD activities. They are based on the O2-specific reaction. Minimum detectable amount of SOD by the Mic-NT method and XOD-NTB method was about 15 ng and 200 ng, respectively. On the other hand, an XOD-NH2OH method which detects SOD activities based on the O2-specific oxidation reaction showed the minimum detectable amount of 2.5 ng. Consequently, SOD-detecting sensitivity of these methods was found to be in the following order: XOD-NH2OH method greater than Mic-NT method greater than XOD-NTB method. In addition, albumin caused a positive error in all three methods. With a monoclonal antibody-aided SOD-analyzing method (EIA method), the minimum detectable amount of SOD was 0.2 ng. The isoenzymes of SOD (Cu, Zn-SOD and Mn-SOD) could be detected separately by 1. deactivating Cu, Zn-SOD with CN- or H2O2 and regarding the remaining activity as Mn-SOD and 2. by deactivating Mn-SOD selectively through pretreatment of the sample with SDS and regarding the remaining activity as Cu, Zn-SOD. TBA method (Yagi's method) has been used frequently for the measurement of serum lipid peroxide.(ABSTRACT TRUNCATED AT 250 WORDS)