Association between enterocyte injury and fluid balance in patients with septic shock: a post hoc exploratory analysis of a prospective observational study

Background

The required fluid volume differs among patients with septic shock. Enterocyte injury caused by shock may increase the need for fluid by triggering a systematic inflammatory response or an ischemia-reperfusion injury in the presence of intestinal ischemia/necrosis. This study aimed to evaluate the association between enterocyte injury and positive fluid balance in patients with septic shock.

Methods

This study was a post hoc exploratory analysis of a prospective observational study that assessed the association between serum intestinal fatty acid-binding protein, a biomarker of enterocyte injury, and mortality in patients with septic shock. Intestinal fatty acid-binding protein levels were recorded on intensive care unit admission, and fluid balance was monitored from intensive care unit admission to Day 7. The association between intestinal fatty acid-binding protein levels at admission and the infusion balance during the early period after intensive care unit admission was evaluated. Multiple linear regression analysis, with adjustments for severity score and renal function, was performed.

Results

Overall, data of 57 patients were analyzed. Logarithmically transformed intestinal fatty acid-binding protein levels were significantly associated with cumulative fluid balance per body weight at 24 and 72 h post-intensive care unit admission both before (Pearson’s r = 0.490 [95% confidence interval: 0.263–0.666]; P < 0.001 and r = 0.479 [95% confidence interval: 0.240–0.664]; P < 0.001, respectively) and after (estimate, 14.4 [95% confidence interval: 4.1–24.7]; P = 0.007 and estimate, 26.9 [95% confidence interval: 11.0–42.7]; P = 0.001, respectively) adjusting for severity score and renal function.

Conclusions

Enterocyte injury was significantly associated with cumulative fluid balance at 24 and 72 h post-intensive care unit admission. Enterocyte injury in patients with septic shock may be related to excessive fluid accumulation during the early period after intensive care unit admission.

Removal of a catheter mount and heat-and-moisture exchanger improves hypercapnia in patients with acute respiratory distress syndrome: A retrospective observational study

ABSTRACT

To avoid ventilator-associated lung injury in acute respiratory distress syndrome (ARDS) treatment, respiratory management should be performed at a low tidal volume of 6 to 8 mL/kg and plateau pressure of ≤30 cmH2O. However, such lung-protective ventilation often results in hypercapnia, which is a risk factor for poor outcomes. The purpose of this study was to retrospectively evaluate the effectiveness and safety of the removal of a catheter mount (CM) and using heated humidifiers (HH) instead of a heat-and-moisture exchanger (HME) for reducing the mechanical dead space created by the CM and HME, which may improve hypercapnia in patients with ARDS.This retrospective observational study included adult patients with ARDS, who developed hypercapnia (PaCO2 > 45 mm Hg) during mechanical ventilation, with target tidal volumes between 6 and 8 mL/kg and a plateau pressure of ≤30 cmH2O, and underwent stepwise removal of CM and HME (replaced with HH). The PaCO2 values were measured at 3 points: ventilator circuit with CM and HME (CM + HME) use, with HME (HME), and with HH (HH), and the overall number of accidental extubations was evaluated. Ventilator values (tidal volume, respiratory rate, minutes volume) were evaluated at the same points.A total of 21 patients with mild-to-moderate ARDS who were treated under deep sedation were included. The values of PaCO2 at HME (52.7 ± 7.4 mm Hg, P < .0001) and HH (46.3 ± 6.8 mm Hg, P < .0001) were significantly lower than those at CM + HME (55.9 ± 7.9 mm Hg). Measured ventilator values were similar at CM + HME, HME, and HH. There were no cases of reintubation due to accidental extubation after the removal of CM.The removal of CM and HME reduced PaCO2 values without changing the ventilator settings in deeply sedated patients with mild-to-moderate ARDS on lung-protective ventilation. Caution should be exercised, as the removal of a CM may result in circuit disconnection or accidental extubation. Nevertheless, this intervention may improve hypercapnia and promote lung-protective ventilation.

Anaphylactic shock in a patient with severe aortic stenosis treated with adrenaline and landiolol for circulatory management: A case report

RATIONALE

We present the first case of a patient with severe aortic stenosis who developed anaphylactic shock and was successfully treated with adrenaline and landiolol, a highly selective β1-receptor blocker, to prevent disruption of the myocardial oxygen supply-demand balance caused by tachycardia.

PATIENT CONCERNS

An 86-year-old woman was scheduled for simultaneous anterior-posterior fixation for a burst fracture of the 12th thoracic vertebra; 200 mg sugammadex, a neuromuscular blocking agent antagonist, was administered postoperatively, and she was extubated without complications. However, 6 min after extubation, her blood pressure decreased abruptly to 55/29 mm Hg, and her heart rate increased to 78 bpm. Then, we intervened with fluid loading, an increased dose of noradrenaline, and phenylephrine administration. However, her blood pressure did not increase.

DIAGNOSES

A general observation revealed urticaria on the lower leg; thus, we suspected anaphylactic shock due to sugammadex administration.

INTERVENTIONS

We carefully administered 2 doses of 0.05 mg adrenaline and simultaneously administered landiolol at 60 μg/kg/min to suppress adrenaline-induced tachycardia. Adrenaline administration resulted in a rapid increase in blood pressure to 103/66 mm Hg and a maximum heart rate of 100 bpm, suppressing excessive tachycardia.

OUTCOMES

The patient's general condition was stable after the intervention, and circulatory agonists could be discontinued the following day. She was discharged from the intensive care unit on the fourth postoperative day.

LESSONS

Landiolol may help control the heart rate of patients with aortic stenosis and anaphylactic shock. The combined use of landiolol and adrenaline may improve patient outcomes; however, their efficacy and risks must be evaluated by studying additional cases.

Allergen-Related Coronary Vasospasm "Kounis Syndrome" Requiring Administration of Epinephrine and a Coronary Vasodilator

Kounis syndrome is an anaphylactic reaction leading to acute coronary syndrome. The acute treatment of anaphylaxis is epinephrine; however, epinephrine may cause coronary vasoconstriction, reduce coronary blood flow, increase myocardial oxygen demand, and worsen myocardial ischemia. On the other hand, coronary vasodilation, a treatment for acute coronary syndrome, can aggravate hypotension in patients with anaphylaxis. Herein, the authors report a case of type II Kounis syndrome, with vasospasm in a patient with coronary disease, requiring the administration of epinephrine and a coronary vasodilator for resuscitation. The authors administered intravenous epinephrine continuously from lower dosages and performed delicate titration. The coronary vasodilator nicorandil, which has little effect on hemodynamics, also was administered. These treatments improved hemodynamics without complications. Circulatory management that considers both anaphylaxis and coronary lesions is crucial to improve prognosis in this syndrome.

Association between endotoxemia and enterocyte injury and clinical course in patients with gram-positive septic shock: A posthoc analysis of a prospective observational study

Endotoxemia often occurs in patients with gram-positive infections. The possible mechanism is thought to be bacterial translocation after enterocyte hypoperfusion injury. However, the association between endotoxemia and enterocyte injury among patients with gram-positive septic shock has never been assessed. The aim of this study was to evaluate the association between endotoxemia and enterocyte injury in gram-positive septic shock patients and to evaluate the association among endotoxemia, subsequent clinical course, and other related factors.This was a posthoc analysis of a prospective observational study that evaluated the capability of intestinal fatty acid-binding protein (I-FABP), an indicator of enterocyte injury, to predict mortality. Among 57 patients in septic shock, those whose causative microorganisms were gram positive were included. The correlation between endotoxin activity (EA), which indicates endotoxemia, and I-FABP levels upon admission to the intensive care unit (ICU), the clinical course, and other related factors were evaluated.A total of 21 patients were examined. One-third of the patients presented with high EA levels at the time of ICU admission. However, there was no significant correlation between EA and I-FABP levels (Spearman ρ = 0.002, P = .993). Additionally, high EA levels were not associated with abdominal complications after ICU admission or mortality. Similarly, high EA levels were not associated with severity scores, inotropic scores, or lactate levels upon ICU admission, which were previously reported to be factors related to high EA levels.In this posthoc analysis, no correlation was observed between endotoxemia and enterocyte injury among patients in gram-positive septic shock. Additionally, high EA levels were not associated with the clinical course and reported factors related to endotoxemia. Although our results need to be validated in a large prospective cohort study, hypoperfusion enterocyte injury might not be a cause of endotoxemia in these patients. Thus, if there is no correlation between EA and I-FABP levels, other mechanisms that induce high EA levels among patients with gram-positive septic shock should be elucidated.

[A Case of Acetaminophen Poisoning Associated with Tramcet Overdose]

Tramcet is a mixture of tramadol and acetaminophen. Acetaminophen poisoning may be caused by excessive intake of Tramcet. A 17-year-old female took excessive quantity of Tramcet before noon. She reported it herself in the emergency room. Her main complaint was nausea and dizziness. Acetaminophen may cause liver damage with dose-dependent manner. Because there was a possibility of acetaminophen poisoning, we started oral acetylcysteine. She was discharged from hospital 5 days later without side effects of acetylecysteine and liver damage.

Comparative Efficacy of Levobupivacaine and Ropivacaine for Epidural Block in Outpatients with Degenerative Spinal Disease

Background: Levobupivacaine has less toxic potential on both the cardiovascular and central nervous system and has been widely used for postoperative epidural analgesia in surgical patients. However, there are few reports on the efficacy of epidural levobupivacaine in outpatients with lumbosacral radiculopathy. This study was carried out to evaluate the comparative efficacy of levobupivacaine and ropivacaine for epidural block in outpatients with degenerative spinal disease and sciatica. Objective: We studied 32 patients (19 men and 13 women) with degenerative spinal disease and sciatica. Study Design: The study was performed in a prospective, randomized, double blind, and crossover fashion. Setting: University medical facility. Methods: The epidural block was produced with a caudal approach (0.125% levobupivacaine or 0.2% ropivacaine, 15 mL). The upper level of analgesia, lumbosacral pain, motor blockade, and hemodynamic changes were evaluated by pin prick, visual analogue scale (VAS), Bromage scale, and arterial blood pressure and heart rate at 15, 30, 60, and 90 minutes after epidural block, respectively. The recovery time to mobilization, ambulation, and spontaneous micturition were measured. Results: There were no significant differences (P < 0.05) in the upper level of analgesia, VAS, and Bromage scale between 0.125% levobupivacaine and 0.2% ropivacaine throughout the time course. There were no significant differences in the recovery times to mobilization, ambulation, and spontaneous micturition between 0.125% levobupivacaine and 0.2% ropivacaine. There were no significant differences in arterial blood pressure and heart rate between the 2 trials throughout the time course. Conclusion: The results showed that 0.125% levobupivacaine and 0.2% ropivacaine for epidural block by a caudal approach provide similar lumbosacral pain relief, hemodynamic effects, and the degree and the recovery of motor blockade in outpatients with degenerative spinal disease and sciatica. Key words: Levobupivacaine, ropivacaine, outpatients, epidural block, degenerative spinal disease with sciatica

Comparative efficacy of levobupivacaine and ropivacaine for epidural block in outpatients with degenerative spinal disease

BACKGROUND

Levobupivacaine has less toxic potential on both the cardiovascular and central nervous system and has been widely used for postoperative epidural analgesia in surgical patients. However, there are few reports on the efficacy of epidural levobupivacaine in outpatients with lumbosacral radiculopathy. This study was carried out to evaluate the comparative efficacy of levobupivacaine and ropivacaine for epidural block in outpatients with degenerative spinal disease and sciatica.

OBJECTIVE

We studied 32 patients (19 men and 13 women) with degenerative spinal disease and sciatica.

STUDY DESIGN

The study was performed in a prospective, randomized, double blind, and crossover fashion.

SETTING

Treatment room for outpatients.

METHODS

The epidural block was produced with a caudal approach (0.125% levobupivacaine or 0.2% ropivacaine, 15 mL). The upper level of analgesia, lumbosacral pain, motor blockade, and hemodynamic changes were evaluated by pin prick, visual analogue scale (VAS), Bromage scale, and arterial blood pressure and heart rate at 15, 30, 60, and 90 minutes after epidural block, respectively. The recovery time to mobilization, ambulation, and spontaneous micturition were measured.

RESULTS

There were no significant differences (P < 0.05) in the upper level of analgesia, VAS, and Bromage scale between 0.125% levobupivacaine and 0.2% ropivacaine throughout the time course. There were no significant differences in the recovery times to mobilization, ambulation, and spontaneous micturition between 0.125% levobupivacaine and 0.2% ropivacaine. There were no significant differences in arterial blood pressure and heart rate between the 2 trials throughout the time course.

CONCLUSION

The results showed that 0.125% levobupivacaine and 0.2% ropivacaine for epidural block by a caudal approach provide similar lumbosacral pain relief, hemodynamic effects, and the degree and the recovery of motor blockade in outpatients with degenerative spinal disease and sciatica.

Astringency of bovine milk whey protein

Whey protein solutions at pH 3.5 elicited an astringent taste sensation. The astringency of whey protein isolate (WPI), the process whey protein (PWP) that was prepared by heating WPI at pH 7.0, and the process whey protein prepared at pH 3.5 (aPWP) were adjusted to pH 3.5 and evaluated by 2 sensory analyses (the threshold method and the scalar scoring method) and an instrumental analysis (taste sensor method). The taste-stimulating effects of bovine and porcine gelatin were also evaluated. The threshold value of astringency of WPI, PWP, and aPWP was 1.5, 1.0, and 0.7 mg/mL, respectively, whereas the gelatins did not give definite astringency. It was confirmed by the scalar scoring method that the astringency of these proteins increased with the increase in protein concentration, and these proteins elicited strong astringency at 10 mg/mL under acidic conditions. On the other hand, the astringency was not elicited at pH 3.5 by 2 types of gelatin. A taste sensor gave specific values for whey proteins at pH 3.5, which corresponded well to those obtained by the sensory analysis. Elicitation of astringency induced by whey protein under acidic conditions would be caused by aggregation and precipitation of protein molecules in the mouth.

Intracerebroventricular administration of endothelin-1 impairs the habituation of rats to a novel environment in conjunction with brain serotonergic activation

The effects of i.c.v. administration of endothelin-1, at a low dose that does not produce abnormal behaviors such as barrel-rolling, on the emotional state of rats exposed to a novel environment were examined. Changes in the emotional state of rats with a novel environment were evaluated in terms of changes in exploratory activity in the hole-board apparatus, i.e., locomotor activity as well as the number and duration of rearing and head-dipping behaviors. Rats treated with i.c.v. saline showed marked exploratory behaviors immediately after exposure to the hole-board apparatus, but these exploratory behaviors decreased rapidly with time. On the other hand, the habituation of rats to a novel environment was prolonged by the i.c.v. administration of endothelin-1 (0.3 and 1 pmol). Furthermore, we also found that i.c.v. administration of endothelin-1 (1 pmol) significantly increased the serotonin (5-hydroxytryptamine) turnover in some brain regions, i.e., the cerebral cortex, hippocampus and midbrain, and the inhibition of brain 5-hydroxytryptamine synthesis by treatment with p-chlorophenylalanine (200 mg/kg/day, s.c.) for 2 days suppressed the behavioral effects of endothelin-1 (1 pmol, i.c.v.). In addition, i.c.v. administration of endothelin-1 (1 pmol) did not affect the spontaneous motor activity of rats. The present study demonstrated that i.c.v. administration of low doses of endothelin-1 impairs the habituation of rats to a novel environment in conjunction with brain 5-hydroxytryptaminergic activation. These results suggest that the central endothelin system may play a significant role in mediating emotionality.

Changes of oligosaccharides and fatty acids in monkey hippocampus by synaptic potentiation

We measured the release of free fatty acids and structural changes of glycoprotein glycans induced by tetraethylammonium (TEA) salt in hippocampal slices of cynomolgus monkey brain. The release of free fatty acids in the hippocampal slices occurred after synaptic potentiation by TEA in a different manner from rat hippocampus. Arachidonic acid release in monkey hippocampus occurred much faster than that in rat. Several types of glycans of monkey hippocampal glycoproteins were determined depending on the duration time after TEA treatment. 5-Mannose was increased within 2 min, while polysialoglycans were increased after 5 min or later. Comparative study of glycans of monkey and rat hippocampal slices revealed the presence of relatively larger amount of sialo- and multi-anntenary glycans in rat than in monkey. These results indicate that the depolarizing stimulation of monkey hippocampal slices induced the change of glycoprotein glycan structures and release of free fatty acids in a different manner from rat hippocampus.

Effect of endotoxin-induced reactive oxygen species on sperm motility

OBJECTIVE

To define the mechanism of infection-induced damage of sperm.

DESIGN

The effect of lipopolysaccharide (LPS)-induced reactive oxygen species (ROS) on sperm motility and its modification by scavengers were investigated.

SETTING

Research laboratory of a university hospital.

PATIENT(S)

Normozoospermic semen samples were obtained from 37 healthy volunteers.

INTERVENTION(S)

The sperms were incubated in the presence of LPS with or without scavengers.

MAIN OUTCOME MEASURE(S)

Sperm motility was evaluated by a sperm quality analyzer (SQAIIB). ROS formation in semen samples was measured by a Berthold luminometer (LB953).

RESULT(S)

Motility of spermatozoa was decreased in the LPS-treated samples compared with that in the control groups. ROS was significantly higher in the LPS-treated groups than in the control groups. The addition of ROS scavengers restored the motility index and suppressed ROS production in the LPS-treated semen samples.

CONCLUSION(S)

These data suggest that endotoxin-induced excessive production of ROS is responsible for the decrease in sperm motility and that antioxidant therapy may be a therapeutic option for infertile men with bacterial genital tract infection.

Point mutation (-69 G-->A) in the promoter region of cholesteryl ester transfer protein gene in Japanese hyperalphalipoproteinemic subjects

Cholesteryl ester transfer protein (CETP) transfers cholesteryl ester (CE) from HDL to apolipoprotein (apo) B-containing lipoproteins and plays a crucial role in reverse cholesterol transport, which is a major protective system against atherosclerosis. Genetic CETP deficiency is the most common cause of a marked hyperalphalipoproteinemia (HALP) in the Japanese, and various mutations have been identified in the coding region as well as in the exon/intron boundaries in the CETP gene. In the present study, we identified a novel mutation in the promoter region of the CETP gene. This mutation was a G-to-A substitution at the -69 nucleotide of the promoter region (-69 G-->A), corresponding to the second nucleotide of the PEA3/ETS binding site (CGGAA) located upstream of the putative TATA box. Four (2.0%) of 196 unrelated subjects with a marked HALP (HDL cholesterol >/=2.59 mmol/L=100 mg/dL) were revealed to be heterozygous for the -69 G-->A mutation, and the allelic frequency of the mutant was 0.0102 in the subjects with a marked HALP. The subjects with the -69 G-->A mutation had low plasma CETP levels. Reporter gene assay showed that this mutation markedly reduced the transcriptional activities in HepG2 cells (8% of wild type). These results suggested that this mutation would be dominant negative. In conclusion, a novel -69 G-->A mutation in the CETP gene causes the decreased transcriptional activity leading to HALP.

Changes in antioxidative mechanisms in elderly patients with non-insulin-dependent diabetes mellitus. Investigation of the redox dynamics of alpha-tocopherol in erythrocyte membranes

BACKGROUND

Recently, it has been suggested that the onset and aggravation of diabetes are closely related to free radicals. Also, vitamin E is a lipophilic free radical scavenger that is localized mainly in biomembranes.

OBJECTIVE

The purpose of this study was to clarify the defensive mechanisms against oxidative stress by investigating the differences in the redox dynamics of alpha-tocopherol in plasma and erythrocyte membranes between elderly patients with non-insulin-dependent diabetes mellitus (NIDDM) and healthy elderly subjects.

METHODS

Total, alpha-, beta-, gamma- and delta-tocopherol and alpha-tocopherolquinone concentrations were determined by high-performance liquid chromatography with a redox detection mode using a series of four coulometric working electrodes.

RESULTS

The alpha-tocopherolquinone/alpha-tocopherol ratio in plasma and erythrocyte membranes was not different between the two groups. Both the alpha-tocopherol concentrations in erythrocyte membranes and ratio of alpha-tocopherol in erythrocyte membranes to alpha- tocopherol in plasma was significantly lower in elderly NIDDM patients than in healthy subjects.

CONCLUSION

These findings suggest that alpha-tocopherol is used normally in both plasma and erythrocyte membranes and alpha-tocopherol uptake in erythrocyte membranes is significantly decreased in elderly NIDDM patients. The functional disorder of the antioxidative activity of alpha-tocopherol in erythrocyte membranes due to impairment of this transfer mechanism may be associated with the pathogenesis of NIDDM.

Singlet oxygen generation from phosphatidylcholine hydroperoxide in the presence of copper

This study pursued whether singlet oxygen ((1)O2) is generated from phosphatidylcholine hydroperoxide (PCOOH), the oxidized modification product of a major constituent of biomembranes and serum lipoproteins. The (1)O2 formation was detected, by utilizing the oxidation of 2,2,6,6-tetramethyl-4-piperidone (TMPD) by (1)O2 to yield 2,2,6,6-tetramethyl-4-piperidone-1-oxyl (TEMPONE), which generates electron spin resonance (ESR) signals. The TEMPONE signal was detected in human plasma with addition of PCOOH by ESR determination after introducing copper(II). The TEMPONE formation was proportional to the amounts of PCOOH added according to moles of active oxygen. The TEMPONE signal intensity was weakened significantly in the presence of beta-carotene and histidine in a concentration-dependent manner, but was not at all decreased by mannitol, Mn-superoxide dismutase and catalase. In addition, HPLC-chemiluminescence analysis demonstrated that incubation with the PCOOH/Cu(II) combination oxidized cholesterol, a relatively oxidation-resistant component, to the cholesterol hydroperoxide. These results reveal that (1)O2 is generated from PCOOH in contact with copper(II). In conclusion, this in-vitro study provides directly the (1)O2 formation in living organisms following the advancement of peroxidation of constitutive lipids.

Protective effect of Ninjin-yoei-to on damage to isolated hepatocytes following transient exposure to tert-butyl hydroperoxide

To establish a simple screening system for estimating efficacy of an agent for an oxidative-related lesion, we investigated the damage in isolated rat hepatocytes exposed to 75 microM tert-butyl hydroperoxide (t-BuOOH) and then subsequently incubated the cells in fresh medium. By electron spin resonance spectroscopy analysis using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), DMPO adducts of tert-butoxyl radicals and carbon center radicals were detected during the t-BuOOH exposure, and DMPO-OH formation was detected after t-BuOOH removal. In t-BuOOH-exposed cells, the level of phosphatidylcholine hydroperoxide (PCOOH), a peroxidative product of biomembranes in the hepatocytes, and the leakage of enzymes into the culture medium were significantly increased. An increase in acid phosphatase (AP) activity representing lysosome destabilization preceded the aspartate oxoglutarate aminotransferase (AST), alanine oxoglutarate aminotransferase (ALT) and lactate dehydrogenase (LDH) leakage. Ninjin-yoei-to added to the culture medium following the t-BuOOH exposure significantly inhibited the PCOOH formation and the leakage of AP, AST, ALT and LDH, concentration-dependently. Ninjin-yoei-to at 1 mg/ml in culture medium completely diminished these increases in enzyme activities down to the background levels found in control experiments and this reduction was greater than the most effective alpha-tocopherol concentration of 20 micromol/ml. Considering all of these results, it is likely Ninjin-yoei-to may exert its protective effect by antioxidative action and membrane stabilization.

Distribution of phospholipid transfer protein in human plasma: presence of two forms of phospholipid transfer protein, one catalytically active and the other inactive

Plasma phospholipid transfer protein (PLTP) plays an important role in the maintenance of plasma high-density lipoprotein (HDL) content and remodeling of HDL in the circulation. In the present study we have used different fractionation methods to investigate the distribution of PLTP in human plasma. A novel enzyme-linked immunosorbent assay developed during the study allowed for simultaneous assessment of both PLTP mass and activity in the fractions obtained. Size-exclusion chromatography and plasma fractionation by nondenaturing polyacrylamide gel electrophoresis (PAGE) yielded similar results demonstrating that PLTP associates in native plasma with two distinct particle populations, while ultracentrifugation with high salt leads to detachment of PLTP from lipoprotein particles and loss of a majority of its phospholipid transfer activity. Interestingly, analysis of the size-exclusion chromatography fractions demonstrated that PLTP exists in the circulation as an active population that elutes in the position of HDL corresponding to an average molecular mass of 160+/-40 kDa and an inactive form with an average mass of 520+/-120 kDa. The inactive fraction containing approximately 70% of the total PLTP protein eluted between HDL and low density lipoprotein (LDL). Thus, the two PLTP pools are associated with different types of lipoprotein particles, suggesting that the PLTP activity in circulation is modulated by the plasma lipoprotein profile and lipid composition.

Styrene inhibits monoamine oxidase A, but not monoamine oxidase B in monkey brain mitochondria

The effects of styrene on mitochondrial monoamine oxidase (MAO) activity in rat and monkey brains were compared in vitro. After preincubation at 25 degrees C for 20 min with 1 mM styrene monomer MAO-A activity in monkey brain was inhibited potently using 5-HT (for MAO-A substrate), but MAO-B activity in monkey brain and platelets were slightly inhibited using beta-PEA (for MAO-B substrate). Styrene monomer also competitively inhibited MAO-A activity in a dose-dependent manner. MAO-A in monkey brain was inhibited by styrene in ascending order of potency: styrene trimer>styrene dimer>styrene monomer. In contrast styrene monomer slightly inhibited both MAO-A and MAO-B activities in rat brain mitochondria. In the present study styrene monomer potently inhibits MAO-A activity, but not MAO-B activity, in monkey brain mitochondria in vitro. These results indicate the inhibiting action of styrene differs depending on animal species and MAO isoforms.

Measurement of human plasma phospholipid transfer protein by sandwich ELISA

BACKGROUND

Plasma phospholipid transfer protein (PLTP) plays a central role in the remodeling of HDLs. Reliable and accurate methods for assaying PLTP concentration are required.

METHODS

A sandwich ELISA for PLTP has been developed, using two monoclonal antibodies against recombinant human PLTP (rhPLTP) expressed in Chinese hamster ovary cells. The ELISA allows for the quantification of PLTP in the range 0.625-15.0 ng/assay (1.2-30.0 mg/L). Intra- and interassay CVs were <3.0% and <4.2% respectively. The assay was used to quantify plasma PLTP concentrations in 132 Japanese subjects (75 males and 57 females).

RESULTS

PLTP concentrations were 12.0 +/- 3. 0 mg/L (mean +/- SD; range, 4.9-20.5 mg/L). No sex difference was observed. Plasma PLTP concentration was positively correlated with HDL-cholesterol (r = 0.72; P: <0.001), apolipoprotein (apo) A-I (r = 0.62; P: <0.001) and HDL(2)-cholesterol (r = 0.72; P: <0.001), and was negatively correlated with triacylglycerol (r = -0.45; P: <0. 001). There was no correlation with plasma apo A-II. These results agree with other evidence that plasma PLTP is associated with large apo A-I-containing lipoproteins. There was no correlation (r = -0. 01) between plasma PLTP and plasma phosphatidylcholine transfer activity (range, 3.5-10.5 micromol. mL(-1). h(-1)), suggesting that PLTP may exist in active and inactive forms.

CONCLUSION

This new ELISA will be of value for further studies of PLTP in health and disease.

A sandwich enzyme-linked immunosorbent assay for human serum paraoxonase concentration

Serum paraoxonase (PON) is associated with plasma high density lipoproteins, and prevents the oxidative modification of low density lipoproteins. We have developed a sensitive sandwich enzyme-linked immunosorbent assay (ELISA), using two monoclonal antibodies against PON, to measure serum PON concentration. The concentration of PON in healthy Japanese subjects was 59.3 +/- 1.3 microgram/mL (mean +/- SEM; n = 87). Serum PON concentrations in relation to the PON 192 genetic polymorphism were: 69.5 +/- 2.9 microgram/mL in the QQ genotype; 63.0 +/- 1.9 microgram/mL in the QR genotype; and 52.8 +/- 1.7 microgram/mL in the RR genotype. Concentrations were significantly lower in the RR than in the QQ genotype (P < 0.01). Serum paraoxonase specific activity was higher in RR than in QQ subjects (18.6 +/- 0.40 vs. 2. 56 +/- 0.05 nmol/min/microgram, P < 0.01), but arylesterase specific activity was unrelated to genotype. PON concentration was positively associated (P < 0.001) with both serum arylesterase activity and, after adjusting for the effect of the position 192 polymorphism, with serum paraoxonase activity. Subjects with angiographically verified coronary heart disease had significantly lower PON concentrations than the healthy controls (52.0 +/- 2.3 microgram/mL; n = 35, P < 0.01). This association was independent of the position 192 genotype. Our new ELISA should be of value for epidemiologic and clinical studies of serum PON concentration. immunosorbent assay for human serum paraoxonase concentration.

Day/night variation of 5-hydroxyindole acetic acid concentration in rat cerebrospinal fluid after acute and long-term administration of a selective serotonin reuptake inhibitor, fluvoxamine

When 30 mg/kg, p.o. of fluvoxamine, a selective serotonin reuptake inhibitor, was administered, significant increases of 3-methoxy-4-hydroxyphenylglycol (MHPG) and 5-hydroxy indole-3-acetic acid (5-HIAA) contents in rat cerebrospinal fluid (CSF) were observed from two days after administration of fluvoxamine in both the light and dark periods and in the dark period of the light/dark cycle, respectively. In long-term treatment with 15 mg/kg, p.o. of fluvoxamine, the level of MHPG in CSF exhibited no difference, whereas the levels of 5-HIAA showed a significant increase during the light periods. These results suggest that fluvoxamine enhances the 5-HT system, but only with long-term treatment.

Mutations in the hepatocyte nuclear factor-4alpha gene in Japanese with non-insulin-dependent diabetes: a nucleotide substitution in the polypyrimidine tract of intron 1b

Mutations of the hepatocyte nuclear factor 4 alpha (HNF-4alpha) gene have been demonstrated in maturity-onset diabetes of the young (MODY) 1 families. To investigate the possibility that the HNF-4alpha gene contributes to the onset of non-insulin-dependent diabetes mellitus (NIDDM) in Japanese patients, we screened all exons and flanking introns of this gene for mutations in 100 patients with NIDDM diagnosed after 25 years of age. We identified two missense mutations: M49V in exon 1c and T1301 in exon 4; and two nucleotide substitutions in introns: cytosine to thymidine at -5 nt in intron 1b and adenine to thymidine at -21 nt in intron 5. We screened an additional 220 diabetic subjects for the polymorphism in intron 1b. The c/t substitution in intron 1b was associated with NIDDM. This substitution in the polypyrimidine tract, an important cis-acting element directing intron removal, is likely to influence pre-mRNA splicing of this gene. T1301 in exon 4 was observed in only two diabetic subjects. This mutation could influence the conformation of this peptide, resulting in changes in ligand binding domain function. M49V in exon 1c was found in both diabetic and non-diabetic subjects; isoforms HNF-4alpha 4, 5, and 6 with this mutation may impair glucose metabolism in tissue. In contrast to the primary cause of nonsense and missense mutations of the HNF-4alpha gene in MODY1, the nucleotide substitution in intron 1b may partially contribute to development of NIDDM in combination with other genetic and environmental factors.

Antioxidant and hepatoprotective actions of the medicinal herb Artemisia campestris from the Okinawa Islands

The antioxidant action of Artemisia campestris was examined in vitro and in vivo. A water extract of A. campestris showed a strong scavenging action of 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydroxyl and superoxide anion radicals. When the extract was given intraperitoneally to mice prior to carbon tetrachloride (CCl4) treatment, CCl4-induced liver toxicity, as seen by an elevation of serum aspartate aminotransferase and alanine aminotransferase activities, was significantly reduced. Depression of the elevation of serum enzyme levels after CCl4-treatment was also observed by oral administration of the extract. In that case, CCl4-derived lipid peroxidation in the liver was decreased by the extract treatment. These results suggest that the extract of A. campestris scavenges radicals formed by CCl4 treatment resulting in protection against CCl4-induced liver toxicity.

[Effects of breeding conditions on neurochemical cholinergic and monoaminergic markers in aged rat brain]

We investigated the effects of breeding conditions on neurochemical markers, muscarinic receptor (mAChR), beta-adrenoreceptor (beta-AdrR), imipramine binding sites (IMBS), choline acetyltransferase (ChAT), acetylcholinesterase (AChE) and monoamine oxidase (MAO) activity in aged rat brains. An increase of affinity (Kd) and the decrease in the number (Vmax) of mAChR were found in the individual aged rats. Concerning IMBS, Kd and Vmax values increased in the individual aged rats. However, no significant changes were observed in the beta-AdrR. The increases of ChAT and MAO activity were found in the aggregated aged rats to compare with in the individual aged rats, while AChE activity decreased in the aggregated aged rats. These changes were also particularly seen in the forebrain of aged rats. These results indicate that the functions of the central nervous system may be reduced in the individual aged rats to compare with in the aggregated aged rats under the breeding conditions.

A new variant of apolipoprotein E (apo E Maebashi) in lipoprotein glomerulopathy

We have previously reported an 8-year-old girl with lipoprotein glomerulopathy. Assessment of serum apolipoprotein E (apo E) in this patient showed a discrepancy between phenotype and genotype, suggesting that she may have a variant of apo E. The present report concerns our analysis of DNA sequences of the apo E gene in the patient: nine base pairs were found to be deleted from exon 4. This mutation would appear to encode a new apo E variant lacking three amino acids. This variant may be associated with the pathogenesis of lipoprotein glomerulopathy.

Changes in monoamine metabolites concentrations in rat cerebrospinal fluid after acute and long-term administration of a selective serotonin reuptake inhibitor, trazodone

In order to clarify the mechanism of the antidepressive effects of trazodone, a selective serotonin reuptake inhibitor, we investigated the dynamics of monoamine metabolites in cerebrospinal fluid (CSF) of free-moving conscious rats by acute and long-term treatment with trazodone. When 100 mg kg-1 p.o. of trazodone were administered, a significant increase of 3-methoxy-4-hydroxyphenylglycol (MHPG) concentration was soon observed in the light period of the light/dark cycle, and a significant decrease of dihydroxy phenyl acetic acid (DOPAC) concentration was observed during the 2 days after administration of trazodone; in contrast, the homovanilic acid (HVA) level was increased. However, we detected no significant changes in the 5-hydroxy indole-3-acetic acid (5-HIAA) concentration during the 3 days. In the case of long-term treatment with 50 mg kg-1, p.o. of trazodone, the levels of MHPG, DOPAC and HVA exhibited no difference when compared with values obtained during saline treatment in either the light or dark period, whereas the levels of 5-HIAA showed a significant increase during the light period. These findings suggest that a long-term treatment with trazodone enhances the serotonergic neurons.

Age-related changes in alpha-tocopherol dynamics with relation to lipid hydroperoxide content and fluidity of rat erythrocyte membrane

Age-related changes in alpha-tocopherol dynamics in plasma and erythrocyte membranes of 10- to 120-week-old rats were investigated by high-performance liquid chromatography (HPLC) with redox detection mode. Furthermore, changes in lipid hydroperoxide content and fluidity of erythrocyte membrane with age were assessed using chemiluminescence-HPLC and Fourier transform infrared spectrophotometer, respectively. A slight increase in the alpha-tocopherolquinone/alpha-tocopherol ratio in erythrocyte membrane and a decrease in the alpha-tocopherol in erythrocyte membrane/alpha-tocopherol in plasma ratio were observed. A significant increase in lipid hydroperoxide content and a marked decrease in the fluidity of erythrocyte membrane were seen with age. These findings suggest that alpha-tocopherol uptake in erythrocyte membrane declines, and utilization rate of alpha-tocopherol in erythrocyte membrane increases age-dependently. These changes, which enhanced lipid peroxidation and consequently reduced membrane fluidity, may be caused by the impairment of this transfer mechanism.

The inhibition of monoamine oxidase activity by various antidepressants: differences found in various mammalian species

The effects of the antidepressant drugs zimeldine, imipramine, maprotiline or nomifensine on mitochondrial monoamine oxidase (MAO) activity in mouse, rat, dog and monkey brains were compared in vitro. Mouse, rat, dog and monkey brain MAO-B activities were inhibited by zimeldine more potently than MAO-A activity. Imipramine inhibited MAO-B more potently than MAO-A activity in mouse and rat brains. When dog and monkey brains were investigated, MAO-A activity was inhibited more potently than MAO-B activity at high concentrations of imipramine, while at low concentrations, MAO-B activity was more potently inhibited. Maprotiline and nomifensine inhibited mouse and rat brain MAO-B activity more potently than MAO-A activity, while the inverse was true for dog and monkey brains. All four drugs are competitive inhibitors of MAO-A, but noncompetitive inhibitors of MAO-B in all animal brains. The respective Ki values of these reagents for monkey brain MAO-A and MAO-B were low compared to those of mouse, rat and dog. These results indicate that monkey brain MAOs are more sensitive to antidepressant drugs than those in rodent brain.

Monitoring of radical scavenging activity of peroral administration of the Kampo medicine Sho-saiko-to in rats

The Kampo medicine Sho-saiko-to scavenged superoxide anion radicals (O2-), hydroxyl radicals (*OH) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) radicals in a dose-dependent fashion. We attempted to investigate the transition of free radical scavenging activity in plasma after oral administration of Sho-saiko-to in rats. From the response-time profile, kinetic parameters including values for Ka (absorption rate constant), Tmax (peak concentration time), T1/2 (half life) and MRT (mean residence time) of radical scavenging activity in plasma could be calculated for the O2-, *OH and DPPH radicals. These parameters calculated from the dynamics of antioxidation are considered a very meaningful procedure to examine the effects of Sho-saiko-to.

[Alterations in neurotransmitter, amino acid and free radical related substances in cerebrospinal fluid in patients with cerebrovascular diseases]

Acetylcholinesterase (AChE), choline, monoamine and its metabolite, amino acid and superoxide dismutase (SOD) levels were measured in cerebrospinal fluid (CSF) in patients with cerebrovascular diseases. Patients were classified into the following four groups; controls: normal subjects without neurological disease, group A: cerebral hemorrhage, group B: cerebral infarction, group C: patients with mental impairment, including those in groups A and B, and a low score on Hasegawa's Dementia Rating Scale. CSF AChE level of groups A, B and C was decreased significantly, while choline concentration from patients showed a increase compared with that of control cases. CSF alanine concentration showed a tendency to increase, while glycine and glutamate tended to decrease. CSF epinephrine, norepinephrine or 3-methoxy-4-hydroxyphenylethylen glycol concentrations of groups A, B and C did not exhibit a significant difference from that in control cases. Some cases with cerebrovascular diseases showed low concentrations of both CSF 5-hydroxyindole acetic acid and homovanillic acid. However, dihydroxyphenyl acetic acid concentration was higher than in control cases. The CSF SOD level was not significantly from that in control cases. The changes in neurochemical substances in the CSF support their use as markers of cerebrovascular disease-related change.