Evaluation of the usefulness of plasma 4β-hydroxycholesterol concentration normalized by 4α-hydroxycholesterol for accurate CYP3A phenotyping

Plasma 4β-hydroxycholesterol (OHC) has drawn attention as an endogenous substrate indicating CYP3A activity. Plasma 4β-OHC is produced by hydroxylation by CYP3A4 and CYP3A5 and by cholesterol autoxidation. Plasma 4α-OHC is produced by cholesterol autoxidation and not affected by CYP3A activity. This study aimed to evaluate the usefulness of plasma 4β-OHC concentration minus plasma 4α-OHC concentration (4β-OHC-4α-OHC) compared with plasma 4β-OHC concentration and 4β-OHC/total cholesterol (TC) ratio in cross-sectional evaluation of CYP3A activity. Four hundred sixteen general adults were divided into 191 CYP3A5*1 carriers and 225 non-carriers. Twenty-six patients with chronic kidney disease (CKD) with CYP3A5*1 allele were divided into 14 with CKD stage 3 and 12 with stage 4-5D. Area under the receiver operating characteristic curve (AUC) for the three indices were evaluated for predicting presence or absence of CYP3A5*1 allele in general adults, and for predicting CKD stage 3 or stage 4-5D in patients with CKD. There was no significant difference between AUC of 4β-OHC-4α-OHC and AUC of plasma 4β-OHC concentration in general adults and in patients with CKD. AUC of 4β-OHC-4α-OHC was significantly smaller than that of 4β-OHC/TC ratio in general adults (p = 0.025), but the two indices did not differ in patients with CKD. In conclusion, in the present cross-sectional evaluation of CYP3A activity in general adults and in patients with CKD with CYP3A5*1 allele, the usefulness of 4β-OHC-4α-OHC was not different from plasma 4β-OHC concentration or 4β-OHC/TC ratio. However, because of the limitations in study design and subject selection of this research, these findings require verification in further studies.

Usefulness of Belimumab in Adult Patients With Systemic Lupus Erythematosus Evaluated Using Single Indexes: A Meta-Analysis and Systematic Review

Background

Belimumab is the first antibody drug approved for systemic lupus erythematosus (SLE), and is a fully human monoclonal antibody that inhibits soluble B lymphocyte stimulator protein. In clinical trials, a composite index was used to assess efficacy of belimumab. However, clinical guidelines on SLE treatment currently use single efficacy indexes.

Objective

The main objective of this study was to perform a meta-analysis to evaluate the efficacy of belimumab utilizing single indexes used in routine clinical practice, rather than the composite efficacy index used in clinical trials during the development phase. As a secondary endpoint, safety was also evaluated.

Methods

Several databases were searched to identify reports published up to December 1, 2021 on randomized controlled trials examining the efficacy of belimumab in adult patients with SLE. From the clinical trial data, efficacy was evaluated using single indexes including the SLE Disease Activity Index (SLEDAI), British Isles Lupus Assessment Group Index, and Physician Global Assessment. Safety was also assessed. Data were synthesized and analyzed using Review Manager 5.4. This study protocol was registered in the UMIN Clinical Trials Registry (Registration number: UMIN000052846).

Results

The search identified 12 reports that met the inclusion criteria. Five reports were included in efficacy evaluation and 9 in safety evaluation. The primary endpoint was SLEDAI. Significantly more belimumab-treated patients achieved a ≥4-point reduction in SLEDAI (relative risk 1.28; 95% confidence interval, 1.16-1.40; P < 0.00001) compared with placebo. Other efficacy endpoints were also improved significantly in the belimumab group. No difference in safety was found between belimumab and placebo.

Conclusions

The present meta-analysis evaluating clinical trial data using various single indexes recommended by clinical guidelines for SLE verifies that addition of belimumab to standard of care is efficacious for moderate-to-severe SLE.

Modulation of pain perception through transcranial alternating current stimulation and its nonlinear relationship with the simulated electric field magnitude

BACKGROUND

Oscillatory activities observed in multiple regions are closely associated with the experience of pain. Specifically, oscillatory activities within the theta- and beta-frequency bands, observed in the left dorsolateral prefrontal cortex (DLPFC), have been implicated in pain perception among healthy individuals and those with chronic pain. However, their physiological significance remains unclear.

METHODS

We explored the modulation of pain perception in healthy individuals by theta- and beta-band transcranial alternating current stimulation (tACS) over the left DLPFC and examined the relationship between the modulation effect and magnitude of the electric field elicited by tACS in the left DLPFC using computational simulation.

RESULTS

Our findings revealed that both theta- and beta-tACS increased the heat pain threshold during and after stimulation. Notably, the simulated electric field magnitude in the left DLPFC exhibited an inverted U-shaped relationship with the pain modulation effect for theta-tACS.

CONCLUSIONS

Our study findings suggested that there would be an optimal electric field strength to produce a high analgesic effect for theta-tACS.

SIGNIFICANCE

The application of theta- and beta-tACS interventions targeting the left DLPFC might facilitate the treatment of chronic pain. Furthermore, the attainment of effective pain modulation via theta-tACS over the DLPFC warrants the use of optimal stimulus intensity.

Rapid and simple quantification of belimumab in human plasma using ultra-high performance liquid chromatography with tandem mass spectrometry

OBJECTIVE

Belimumab is a monoclonal antibody against the B-lymphocyte stimulating factor and is approved for the treatment of patients with systemic lupus erythematosus (SLE) not responding adequately to existing therapies. In this study, we established and validated an assay for quantifying belimumab in human plasma.

METHODS

From the peptides generated by trypsin digestion of belimumab, in silico analysis was used to search for unique peptides to determine the surrogate peptides. Samples were trypsin digested, pretreated with solid phase extraction, and analyzed by ultra-high performance liquid chromatography with tandem mass spectrometry (UHPLC-MS/MS) to quantify the surrogate peptide in the samples. The assay was validated according to the Food and Drug Administration (FDA) bioanalytical method validation guidance. We used the established assay to quantify plasma belimumab concentrations in two SLE patients treated with belimumab.

RESULTS

Among the unique peptides identified by the in silico analysis, the peptide with the best peak shape when measured by UHPLC-MS/MS was selected as the surrogate peptide. The validation results of this assay met the acceptable criteria recommended by the FDA guidance. The lower limit of quantification (LLOQ) for belimumab was 2 µg/mL. Recovery rates and matrix effects when corrected for internal standards were 91.5-114.3 % and 96.9-108.4 %, respectively. Plasma concentrations of belimumab were measured in 12 samples from two belimumab-treated SLE patients. All concentrations were within the calibration range.

CONCLUSIONS

We have established and validated a method for measuring plasma belimumab concentrations using UHPLC/MS-MS. By measuring plasma belimumab concentrations in more patients, this method is expected to contribute to appropriate use of belimumab.

Relationship of plasma 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid concentration with OATP1B activity in patients with chronic kidney disease

Organic anion-transporting polypeptides (OATP)1B are drug transporters mainly expressed in the sinusoidal membrane. Many studies have suggested that OATP1B activity is affected by genetic factor, the uremic toxin 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF), and inflammatory cytokines, such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6). Coproporphyrin-I (CP-I) is spotlighted as a highly accurate endogenous substrate of OATP1B. We previously reported a positive correlation between plasma CMPF and CP-I concentrations in patients with chronic kidney disease (CKD). The present study evaluated the impact of genetic polymorphisms, CMPF, IL-6, TNF-α, and estimated glomerular filtration rate (eGFR) on individual differences in OATP1B activity in patients with CKD. Seventy-three patients with CKD who received kidney transplant at least 3 months earlier were analyzed. Plasma CP-I concentration was higher in OATP1B1*15 carriers than in non-carriers. In all patients, CP-I did not correlate significantly with CMPF, IL-6, TNF-α, or eGFR. However, when the dataset was cut off at CMPF concentration of 8 and 7 μg/mL, 4 μg/mL, 3 μg/mL or 2 μg/mL, CMPF correlated positively with CP-I, and correlation coefficient tended to be higher as plasma CMPF concentration was lower. In conclusion, OATP1B1*15 impacted OATP1B activity in patients with CKD, but IL-6 and TNF-α did not. However, the impact of CMPF on OATP1B activity was limited to low CMPF concentrations, and the effect could be saturated at high concentrations. When prescribing an OATP1B substrate drug for patients with CKD, the OATP1B1*15 carrier status and plasma CMPF concentration may need to be considered to decide the dose regimen.

Evaluation of effects of indoxyl sulfate and parathyroid hormone on CYP3A activity considering the influence of CYP3A5 gene polymorphisms

AIMS

Indoxyl sulfate and parathyroid hormone (PTH), which accumulate in chronic kidney disease (CKD), have been reported to reduce cytochrome P450(CYP)3A activity. Homozygotes of the CYP3A5*3 allele have reduced CYP3A5 activity compared to carriers of at least one CYP3A5*1 allele. 4β-Hydroxycholesterol (4β-OHC) has been established as an endogenous substrate reflecting CYP3A activity. 4β-OHC is produced through hydroxylation by CYP3A4 and CYP3A5 and by autoxidation of cholesterol, whereas 4α-hydroxycholesterol (4α-OHC) is produced solely by autoxidation of cholesterol. This study focused on CKD patients and evaluated the effects of plasma indoxyl sulfate and intact-PTH concentrations on plasma 4β-OHC concentration, 4β-OHC/total cholesterol ratio and 4β-OHC-4α-OHC, with consideration of the influence of CYP3A5 polymorphism.

METHODS

Sixty-three CKD patients were analysed and divided into CYP3A5 carrier group (n = 26) and non-carrier group (n = 37).

RESULTS

Plasma indoxyl sulfate significantly correlated inversely with 4β-OHC concentration and with 4β-OHC-4α-OHC in both the CYP3A5*1 carrier group (r = -0.42, P = .034; r = -0.39, P = .050, respectively) and the non-carrier group (r = -0.45, P = .0054; r = -0.39, P = .019, respectively). However, multiple regression analysis did not identify plasma indoxyl sulfate concentration as a significant independent factor associated with any of the CYP3A activity indices. There was no significant correlation between plasma intact-PTH concentration and any of the CYP3A activity indices.

CONCLUSIONS

The present results suggest that plasma indoxyl sulfate and intact-PTH concentrations do not have clinically significant effects on CYP3A activity in patients with CKD.

Early Release Science of the exoplanet WASP-39b with JWST NIRSpec PRISM

Transmission spectroscopy1-3 of exoplanets has revealed signatures of water vapour, aerosols and alkali metals in a few dozen exoplanet atmospheres4,5. However, these previous inferences with the Hubble and Spitzer Space Telescopes were hindered by the observations' relatively narrow wavelength range and spectral resolving power, which precluded the unambiguous identification of other chemical species-in particular the primary carbon-bearing molecules6,7. Here we report a broad-wavelength 0.5-5.5 µm atmospheric transmission spectrum of WASP-39b8, a 1,200 K, roughly Saturn-mass, Jupiter-radius exoplanet, measured with the JWST NIRSpec's PRISM mode9 as part of the JWST Transiting Exoplanet Community Early Release Science Team Program10-12. We robustly detect several chemical species at high significance, including Na (19σ), H2O (33σ), CO2 (28σ) and CO (7σ). The non-detection of CH4, combined with a strong CO2 feature, favours atmospheric models with a super-solar atmospheric metallicity. An unanticipated absorption feature at 4 µm is best explained by SO2 (2.7σ), which could be a tracer of atmospheric photochemistry. These observations demonstrate JWST's sensitivity to a rich diversity of exoplanet compositions and chemical processes.

Positive correlation between organic anion transporter 1B function indicated by plasma concentration of coproporphyrin-I and blood concentration of cyclosporin A in real-world patients

AIMS

Cyclosporin A (CyA) has potent inhibitory activity on organic anion transporting polypeptide 1B (OATP1B), causing drug-drug interactions with its substrate drugs. 3-carboxy-4-methyl-5-propyl-2-furanpropionate (CMPF), a uraemic toxin, has also been suggested to inhibit OATP1B activity. Recent study has identified coproporphyrin-I (CP-I) as a specific endogenous substrate for OATP1B, which is useful to indicate OATP1B activity. We investigated the relationship of CP-I with CyA and CMPF concentrations in patients taking CyA.

METHODS

In total, 121 blood samples from 74 patients who took CyA and underwent routine therapeutic drug monitoring were divided into trough and peak samples.

RESULTS

CyA and CP-I concentrations were significantly higher in peak samples than in trough samples. A positive correlation between CP-I and CyA concentrations was found in all samples and in trough and peak samples, while no correlation was observed between CP-I and CMPF concentrations. Multiple regression analysis identified CyA and C-reactive protein concentrations as independent factors affecting CP-I concentration, with blood CyA concentration having markedly greater contribution to plasma CP-I concentration.

CONCLUSION

The present study suggests that CyA inhibits OATP1B activity in a concentration-dependent manner in clinical setting, and that dose adjustment of OATP1B substrate drugs coadministered with CyA according to plasma CMPF concentration may not be necessary.

Highly sensitive simultaneous quantification of indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid in human plasma using ultra-high performance liquid chromatography coupled with tandem mass spectrometry

Indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid are uremic toxins that accumulate in renal failure, and have been reported to decrease the activities of the drug metabolizing enzyme cytochrome P450 3A and the drug transporter organic anion transporting polypeptides 1B, respectively. In this study, we established and validated an assay for simultaneous quantification of indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid in human plasma. The samples were pretreated by SPE, and measured by UHPLC-MS/MS. The validation results for this assay were within the acceptable limits recommended by the US Food and Drug Administration, with a lower limit of quantification of 0.05 μg/mL for both indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid. Recovery rates of indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid corrected by internal standard were 100.7%-101.9% and 100.2%-101.3%, respectively. Matrix effects of indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid corrected by internal standard were 101.1%-105.5% and 97.0%-103.8%, respectively. The validated assay was used to analyze indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid concentrations in the plasma samples of healthy volunteers and patients with chronic kidney disease. All the measured plasma indoxyl sulfate and 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid concentrations were within the calibration ranges. This novel method may contribute to predict the activities of drug metabolizing enzymes and drug transporters in individual patients. This article is protected by copyright. All rights reserved.

Intravenous Administration of Dehydroxymethylepoxyquinomicin With Polymer Enhances the Inhibition of Pancreatic Carcinoma Growth in Mice

BACKGROUND/AIM

Pancreatic cancer, which exhibits resistance to cytotoxic and molecular targeted drugs, has an extremely poor prognosis. Nuclear factor-κB (NF-κB) is constitutively activated in many pancreatic cancer cases. Although the NF-κB inhibitor dehydroxymethylepoxyquinomicin (DHMEQ) has exhibited anti-cancer effects in pancreatic cancer models, its poor solubility limits its use to intraperitoneal administration.

MATERIALS AND METHODS

Poly(2-methacryloyloxyethyl phosphorylcholine-co-n-butyl methacrylate) (PMB) forms stable polymer aggregates with DHMEQ. The stability of DHMEQ aggregated with PMB in the human blood was measured by high-performance liquid chromatography-mass spectrometry (HPLC-MS) ex vivo. Anti-pancreatic cancer effects in AsPC-1 and MIA PaCa-2 pancreatic cancer cells were evaluated by cell growth inhibition assay in vitro and tumor growth inhibition assay in vivo.

RESULTS

DHMEQ aggregated with PMB (PMB-DHMEQ) remained detectable after 60 min of incubation in the human blood, whereas DHMEQ aggregated with carboxymethyl cellulose (CMC-DHMEQ) was barely detectable. PMB-DHMEQ significantly inhibited AsPC-1 and MIA PaCa-2 cell growth in vitro compared to CMC-DHMEQ. Intravenous administration of PMB-DHMEQ reduced the tumor volume and liver metastasis compared to untreated or CMC-DHMEQ-treated mice.

CONCLUSION

Aggregation with PMB improved the solubility of DHMEQ, and effectively inhibited pancreatic cancer cell growth both in vitro and in vivo.

Association between MR-proADM concentration and treatment intensity of antihypertensive agents in chronic kidney disease patients with insufficient blood pressure control

Response to antihypertensive drugs in patients with chronic kidney disease (CKD) has great interindividual variability. Adrenomedullin (ADM) is produced abundantly in hypertension, but clearance is very rapid. Mid-regional proADM (MR-proADM) produced from an ADM precursor is considered a surrogate biomarker for quantification of ADM. We investigated the association of MR-proADM with antihypertensive resistance in CKD patients with poor blood pressure (BP) control. This cross-sectional study analyzed 33 CKD patients with poor BP control defined as failure to achieve target BP despite at least two classes of antihypertensive drugs. Treatment intensity score was calculated to facilitate comparability of antihypertensive regimens across subjects taking different drugs. Plasma MR-proADM concentration was measured using ultra-performance liquid chromatography coupled with tandem mass spectrometry. Plasma MR-proADM concentration correlated with estimated glomerular filtration rate (eGFR) (r =  - 0.777, p < 0.001). Treatment intensity score correlated positively with plasma MR-proADM concentration (r = 0.355, p = 0.043), and the correlation was further enhanced after correction by weight (r = 0.538, p = 0.001). Single and multiple regression analysis identified MR-proADM concentration (p = 0.005) as independently associated with weight-corrected treatment intensity score. MR-proADM may be useful as a biomarker to determine the therapeutic intensity of antihypertensive drugs in CKD patients with poor BP control.

Influences of smoking on central blood pressure in hypertensive subjects

Background/Introduction

Smoking is known to induce systemic vascular damage, leading to cardiovascular diseases. Recent studies demonstrated that central blood pressure has a greater impact on cardiovascular events than brachial blood pressure.

Purpose

We investigated influences of habitual smoking on central systolic blood pressure (CSBP) in hypertensive subjects.

Methods

A total of 5630 subjects (male = 2622, 51.7±12.0 year-old at baseline), who visited our hospital for a physical check-up at least twice during the last 10 years and underwent CSBP measurement at each visit, were enrolled, and they were divided into three groups; normotensive (n=4634), non-treated hypertensive (n=91) and treated hypertensive subjects (n=905). Then, the influences of smoking on the average and yearly changes of CSBP (median follow-up 5 years) were analyzed. Brachial blood pressure (oscillometer) and radial artery pressure waveforms (tonometer) were recorded using an automated device, and the pressure corresponding to the second systolic peak of radial pressure waveforms was taken as CSBP (HEM-9000AI, Omron Healthcare, Kyoto). Hypertension was defined as brachial BP ≥140/90mmHg or the use of antihypertensive medications. A yearly change in CSBP was calculated in each subject by linear regression analysis using longitudinal data.

Results

The average CSBP was higher in habitual smokers than in non-smokers when analyzed in normotensive (109.1±11.7 vs. 107.6±12.8 mmHg, p&lt;0.001) and non-treated hypertensive subjects (150.7±14.8 vs. 142.8±16.7 mmHg, p&lt;0.05), whereas in hypertensive subjects under medication the average CSBP was lower in smokers than in non-smokers (124.6±12.4 vs. 127.8±13.6 mmHg, p&lt;0.01). Smoking status did not affect yearly changes of CSBP in normotensive (habitual smokers vs. non-smokers; 1.38±6.00 vs. 1.44±6.04 mmHg/year), treated hypertensive (−0.16±7.08 vs. −0.66±8.24 mmHg/year), and non-treated hypertensive subjects (4.09±15.1 vs. −0.53±10.3 mmHg/year).

Conclusions

Habitual smoking increases CSBP, however, antihypertensive medications counteract the unfavorable effects of smoking on CSBP. These results imply a new pathway underlying the development of cardiovascular diseases in smokers. Unfavorable changes in the cardiovascular system caused by smoking may quite slowly progress that short period of observation in the present study could not have detected enhanced yearly increases of CSBP by smoking.

Funding Acknowledgement

Type of funding sources: None.

Relationship between year-to-year blood pressure variability and target organ damage in the general population

Background/Introduction

Visit-to-visit blood pressure variability (BPV) is a strong predictor of cardiovascular events as well as target organ damage (TOD) in hypertension. However, effects of year-to-year BPV on the development of TOD have not been investigated in the general population.

Purpose

The present study was designed to investigate a possible relationship between year-to-year BPV and TOD in the general population.

Methods

Consecutive 5542 subjects (male=3771, 58.6±10.7 yea-old) who visited our hospital for an annual physical check-up for 5 years in a row during 2008 and 2013 were enrolled. The average, standard deviation (SD), coefficient of variation (CV), and average real variability (ARV) of systolic blood pressure (SBP) were calculated using data during the period. Other baseline data were obtained in 2013; left ventricular hypertrophy (LVH; Sokolow-Lyon voltage &gt;3.8 mV and/or Cornell product &gt;2440 mm ms) and kidney impairment (estimated glomerular filtration rate; eGFR&lt;60) were taken as TOD. Then, subjects without TOD at baseline (2013) (n=3801, male=2584, 57.4±10.4 yea-old) were followed up until 2019 (median = 5 years) and the impact of BPV on the development of TOD was investigated.

Results

The average, SD, CV and ARV of SBP were 123.8 mmHg, 8.04 mmHg, 6.50%, and 9.19 mmHg, respectively. At baseline, these parameters were higher in subjects with TOD than those without TOD (Table 1-A). During the follow-up of subjects without TOD at baseline, LVH and kidney impairment developed in 425 and 623 subjects (24.7 and 35.8 per 1000 person-year), respectively. In retrospective analysis, the average, SD, and ARV were higher in subjects with than without future TOD (Table 1-B). Although some indices of year-to-year BPV predicted future development of TOD in univariate Cox-hazard analysis, only the average of SBP predicted incident TOD after adjustment.

Conclusions

Year-to-year BPV is a marker of the incident TOD in the general population. However, these indices do not independently predict the onset of TOD and, thus, there may be unknown pathway that links TOD and BPV.

Funding Acknowledgement

Type of funding sources: None. Table 1. BP variability and TODTable 2. Cox-hazard analyses

Factors Influencing Plasma Coproporphyrin-I Concentration as Biomarker of OATP1B Activity in Patients With Rheumatoid Arthritis

Organic anion transporting polypeptides (OATPs) 1B are drug transporters mainly expressed in the sinusoidal membrane. In previous reports, genetic factor, 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid (CMPF), which is one of the uremic toxins, inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) decreased OATP1B1 activity in vitro, but in vivo effects of these factors have not been elucidated. Plasma coproporphyrin-I (CP-I) is spotlighted as a highly accurate endogenous substrate of OATP1B. This study focused on patients with rheumatoid arthritis (RA) and evaluated the influence of several factors comprising gene polymorphisms, uremic toxins, and inflammatory cytokines on OATP1B activity using plasma CP-I concentration. Thirty-seven outpatients with RA who satisfied the selection criteria were analyzed at the time of recruitment (baseline) and at the next visit. OATP1B1*15 carriers tended to have higher CP-I concentration compared with noncarriers. Plasma CP-I correlated positively with CMPF concentration, but did not correlate with IL-6 or TNF-α concentration. Multiple logistic regression analysis by stepwise selection identified plasma CMPF concentration and OATP1B1*15 allele as significant factors independently affecting plasma CP-I concentration at baseline and at the next visit, respectively. In conclusion, the present results suggest that inflammatory cytokines do not have clinically significant effects on OATP1B activity, whereas the effects of genetic polymorphisms and uremic toxins should be considered.

Relationship of hemoglobin level and plasma coproporphyrin-I concentrations as an endogenous probe for phenotyping OATP1B

Plasma coproporphyrin‐I (CP‐I) concentration is used as a sensitive and selective endogenous probe for phenotyping organic anion transporting polypeptides 1B (OATP1B) activity in many studies. CP‐I is produced in the process of heme synthesis, but the relationship between plasma CP‐I concentrations and heme synthesis activity is unknown. In this study, we evaluated the relationship between plasma CP‐I concentration and hemoglobin level as a biomarker of heme synthesis activity. The data of 391 subjects selected from the Japanese general population were analyzed. One hundred twenty‐six participants had OATP1B1*15 allele, 11 of whom were homozygous (OATP1B1*15/*15). Multiple regression analysis identified hemoglobin level as an independent variable associated with plasma CP‐I concentration (p < 0.0001). A significant positive correlation was observed between hemoglobin level and plasma CP‐I concentration in participants without OATP1B1*15 allele (n = 265; r_s = 0.35, p < 0.0001) and with OATP1B1*15 allele (n = 126; r_s =0.27, p = 0.0022). However, Kruskal–Wallis test showed no large difference in Kruskal–Wallis statistics between the distribution of plasma CP‐I concentrations and that of ratio of plasma CP‐I to hemoglobin among six OATP1B1 polymorphism groups. These findings suggest that the hemoglobin level seems to reflect biosynthesis of CP‐I. However, correction by hemoglobin level is not required when using basal plasma CP‐I concentration for phenotyping OATP1B activity.

Simultaneous quantification of arctigenin and its glucuronide conjugate in mouse plasma using ultra-high performance liquid chromatography coupled to tandem mass spectrometry

Arctigenin is a natural lignin and a main active component of Fructus arctii, the dried fruit of Arctium lappa. This compound was reported to have some biological activities such as anti-inflammatory, antioxidant, antiviral, renoprotective, and antitumor effects. Arctigenin is mainly metabolized to arctigenin-4'-O-glucuronide by UDP-glucuronosyltransferase. In this study, a simultaneous quantification method was established and validated for measuring arctigenin and arctigenin-4'-O-glucuronide in mouse plasma using ultra-high performance liquid chromatography with tandem mass spectrometry. The assay fulfilled the requirements of the United States Food and Drug Administration guideline for assay validation, with a lower limit of quantification of 2.00 ng/mL for arctigenin and 50.0 ng/mL for arctigenin-4'-O-glucuronide. The recovery rate and matrix effect ranged from 78.4 to 102.8% and 92.5 to 106.3%, respectively, for arctigenin, and 74.3 to 109.2% and 94.9 to 110.2% for arctigenin-4'-O-glucuronide. The method was applied to the measurement of plasma concentrations of arctigenin and arctigenin-4'-O-glucuronide in the plasma of mice after administration of arctigenin. All measured concentrations were within the calibration ranges. Our novel method may be useful to measure plasma arctigenin and arctigenin-4'-O-glucuronide concentrations, and contribute to evaluate the pharmacokinetics of arctigenin and arctigenin-4'-O-glucuronide in mice.

Effect of advancing age on dietary salt intakes: a 10-year follow-up study

Background/Introduction

The National Nutrition Survey in Japan indicated that dietary salt intake of the Japanese is gradually decreasing for the last several decades, while salt intakes are higher in elderly than young people. There is no survey on the alteration of salt intakes with advancing age in individuals.

Purpose

The present study investigated effects of aging on salt intakes in individuals.

Methods

A total of 2600 subjects (men; 1787, age; 30 to 79 years-old at 2008) who participated in our physical check-up program both in 2008 and 2018 were enrolled. Individual dietary salt intakes in 2008 and 2018, which were estimated using a spot urine by a previously reported method, were compared.

Results

The mean age and salt intakes at 2008 were 53.9±10.0 years and 12.2±3.2 g/day in men and 54.4±9.2 years and 8.3±2.1 g/day in women, respectively. Salt intake increased to 13.2±3.3 g/day in men and 8.8±2.2 g/day in women during the 10 years. Salt intakes were higher in hypertensive than normotensive subjects both at 2008 and 2018, but changes of blood pressure category were not associated with those of salt intakes during the 10 years (table). Changes in salt intakes in each decade are shown in Figure. Salt intakes in each decade increased with advancing age both in men and women until their 70s. Salt intakes in people in their 60s and 70s at 2018 were higher than those at 2008. Similar results were obtained in subjects without any anti-hypertensive medications (n=1667) (data not shown).

Conclusions

The observational follow-up study revealed that salt intakes in each individual increased after the interval of 10 years in both men and women. The results suggest that the sense of taste changes with advancing age in young adults as well as elderly persons, which may be related with alterations of lifestyle.

Age difference in changes of salt intake

Funding Acknowledgement

Type of funding source: None

What is the optimal blood pressure level for kidney in the general population?

Background/Introduction

Hypertension induces kidney dysfunction, and vice versa. Furthermore, kidney dysfunction can be a risk factor for cardiovascular diseases as well as end-stage of kidney disease. Although blood pressure (BP) control is necessary to prevent deterioration of kidney function, strict BP control may deteriorate kidney function.

Purpose

The present observational study investigated effects of BP levels on the incidence of chronic kidney disease (CKD) in the general population.

Methods

A total of 12,753 subjects with normal kidney function (estimated glomerular filtration rate [eGFR] ≥60 mL/min per 1.73 m2) (male 7,707, mean age 51.8 years) who visited our hospital for an annual physical check-up from April 2010 to March 2018 were enrolled. After baseline examination, subjects were followed up until March 2019 (median 1769 days) with the endpoint being the development of CKD (eGFR&lt;60 mL/min per 1.73 m2). The modified MDRD formula for Japanese was used to calculate eGFR. Hypertension was defined as BP ≥140/90mmHg or the use of antihypertensive medication.

Results

During the follow-up period, 1,604 subjects developed CKD (26.9 per 1,000 person-years) with the incidence being more frequent in hypertensive (n=3,098) than normotensive (n=9,655) subjects at enrollment (44.2 vs. 21.5 per 1,000 person-years, respectively; hazard ratio [95% confidence interval] from multivariate Cox proportional analysis 1.205 [1.061–1.369]). Hazard ratio of systolic BP at baseline was 1.006 [1.002–1.010] in a multivariate Cox proportional hazard regression model adjusted for possible risk factors. The incidence was lower in subjects without hypertension throughout the follow-up period (normotension group, n=7,866) than those who were diagnosed as having hypertension at least once during the period (hypertension group, n=4,887) (23.1 vs. 32.3 per 1,000 person-years, p&lt;0.001). In the normotension group, subjects with average BP &lt;120/80mmHg had lower incidence of CKD than in those with BP ≥120/80mmHg (17.2 vs. 36.1 per 1,000 person-years, p&lt;0.001). In contrast, in the hypertension group, the incidences of CKD in subjects with average BP &lt;120/80, 120–139/80–89 and ≥140/90mmHg were 34.3, 25.8, and 54.4 per 1,000 person-years, respectively (p&lt;0.001). Moreover, in hypertensive subjects under medication (n=2,002) with average BP &lt;120/80, 120–139/80–89 and ≥140/90mmHg, the incidence of CKD was 65.5, 41.3, and 64.3 per 1,000 person-years, respectively (p&lt;0.01).

Conclusions

The incidence of CKD was higher in hypertensive than in normotensive subjects. The lower BP was associated with the lower incidence of CKD in normotensive subjects, while strict BP control may increase the risk of CKD in hypertensive subjects.

Funding Acknowledgement

Type of funding source: None

Excessive salt intake is a significant predictor for future development of metabolic syndrome in the general population

Background/Introduction

Dietary salt consumption is one of the most important modifiable factors in our lifestyle and restriction of dietary salt results in the reduction of blood pressure in previous studies. Excessive salt intake causes cardiovascular diseases independently of its effects on blood pressure. Since metabolic syndrome also increases a risk of cardiovascular disease, there may be some association between salt intake and metabolic syndrome.

Purpose

The present study was designed to investigate a possible relationship between salt intake and future development of metabolic syndrome in the general population.

Methods

Consecutive 12,256 subjects without metabolic syndrome (male=7,053, 52.1±12.3 year-old) who visited our hospital for an annual physical check-up from April 2010 to March 2018 were enrolled. After baseline examination, subjects were followed up until March 2019 (median 1,582 days) with the endpoint being the development of metabolic syndrome. Metabolic syndrome was diagnosed according to the Japanese criteria (2005). Individual salt intake was estimated using a spot urine by a previously reported method.

Results

Salt intake was 11.9±3.0 g/day in male and 8.2±2.1 g/day in female subjects at baseline. During the follow-up period, 1,669 subjects developed metabolic syndrome (29.9 per 1,000 person-year) with the incidence being more frequent in male than female subjects (41.8 vs. 14.2 per 1,000 person-year). Non-adjusted hazard ratio (HR) (95% confidence interval [CI]) of salt intake for the development of metabolic syndrome was 1.157 (1.142–1.173). In analysis where subjects were divided into gender-specific quartiles according to the baseline salt intake, Kaplan-Meyer curve analysis revealed that the incidence of metabolic syndrome were increased across the quartiles (20.6, 25.0, 32.4, and 42.7 per 1,000 person-years; logrank p&lt;0.001). Multivariate Cox proportional hazard analysis adjusted for age, gender, body mass index, systolic blood pressure, heart rate, serum creatinine, uric acid, fasting plasma glucose, low-density lipoprotein cholesterol, triglyceride, hemoglobin and current smoking habit at baseline revealed that salt intake predicted the new onset of metabolic syndrome (HR: 1.036, 95% CI: 1.019–1.054).

Conclusions

Excessive salt intake is significantly associated with the new development of metabolic syndrome in the general population. The results suggest that salt restriction prevents metabolic syndrome as well as hypertension leading to cardiovascular diseases.

Funding Acknowledgement

Type of funding source: None

Substantially Increased Plasma Coproporphyrin-I Concentrations Associated With OATP1B1*15 Allele in Japanese General Population

Coproporphyrin-I (CP-I) in plasma is a sensitive and specific endogenous probe for phenotyping organic anion transporting polypeptides 1B (OATP1B, encoded by SLCO1B). A few small-scale studies suggested that plasma CP-I concentration is affected by OATP1B1 polymorphism, but detailed studies are lacking. In this large-scale study, we measured plasma CP-I concentrations in 391 subjects from the Japanese general population, and evaluated the relationship between plasma CP-I concentrations and OATP1B1 polymorphisms to further assess the utility of plasma CP-I concentrations as an endogenous OATP1B probe. Plasma CP-I concentrations were 0.45 ± 0.12, 0.47 ± 0.16, 0.47 ± 0.20, 0.50 ± 0.15, 0.54 ± 0.14, and 0.74 ± 0.31 ng/mL in participants with OATP1B1*1b/*1b (n = 103), *1a/*1b (n = 122), *1a/*1a (n = 40), *1b/*15 (n = 74), *1a/*15 (n = 41), and *15/*15 (n = 11), respectively, showing an ascending rank order with significant difference (P < 0.0001). Post hoc analysis revealed significant increases in plasma CP-I concentration in OATP1B1*1b/*15 (P = 0.036), *1a/*15 (P = 0.0005), and *15/*15 (P = 0.0003) groups compared with the OATP1B1*1b/*1b group. There was no significant difference among OATP1B genotypes in plasma concentration of 3-carboxy-4-methyl-5-propyl-2-furanpropanoic acid, a uremic toxin reported to decrease OATP1B activity in vivo. These findings confirm the utility of plasma CP-I concentrations as an endogenous biomarker for phenotyping of OATP1B activity. Plasma CP-I concentration is potentially useful for the study of drug-drug interactions via OATP1B or individual dose adjustment of OATP1B substrates.

Clear evidence for element partitioning effects in a Ti-6Al-4V alloy by the first-principles phase field method

Ti-6 wt% Al-4 wt% V (Ti64) is an α + β titanium alloy, in which the alloying components strongly affect the mechanical properties. In this report, element partitioning effects in Ti64 are investigated by using the first-principles phase field (FPPF) method, which has recently been proposed by our group. In the FPPF method, the local free energy is calculated using a cluster expansion method in combination with density functional theory and the temperature effect is incorporated using potential renormalization theory. We have succeeded in identifying enrichment of Al (V) in the α (β) phase, i.e., the clear evidence for the element partitioning effects of Al and V, without using any thermodynamical parameter. The transformation of the β phase and the α phase in microstructure is investigated by varying the V and Al concentrations by a small amount. Our results are in excellent agreement with the recent experimental results, showing the validity of the FPPF method for ternary alloys.

1415Dose antihypertensive medication improve accelerated age-dependent decline of GFR in hypertension?

Background/Introduction

An impairment of kidney function is a risk not only for end stage renal disease but also for cardiovascular events. Hypertension is known to accelerate an age-dependent decline in glomerular filtration rate (GFR).

Purpose

Effects of antihypertensive medications on yearly changes of estimate GFR (eGFR) in hypertensive patients were investigated.

Methods

Consecutive 5110 subjects (male=3196, 52.3±11.3 year-old) who participated in our physical check-up program during 2010 and 2012 were enrolled and followed up for 5 years. The average and the yearly change of eGFR during the 5 years were calculated in each individual and the both values were compared in hypertensive and normotensive subjects. Effect of antihypertensive medication on eGFR was also investigated. The modified Modification of Diet in Renal Disease study formula for the Japanese population was used for calculating eGFR.

Results

In hypertensive subjects (n=1408), the baseline and the average of eGFR were smaller (74.8±14.6 vs. 80.4±13.6, p<0.001 and 72.1±13.2 vs. 77.9±11.9 mL/min per 1.73 m2, p<0.001, respectively) and the yearly decline of eGFR was greater (0.96±1.41 vs. 0.84±1.19 mL/min per 1.73 m2 per year, p<0.01) than in normotensive subjects (n=3702). The baseline and the average of eGFR were smaller in hypertensive patients with (n=1234) than without (n=174) antihypertensive medication (74.3±14.6 vs. 78.3±13.8, p<0.001 and 71.7±13.2 vs. 74.9±12.7 mL/min per 1.73 m2, p<0.01, respectively). Although the yearly decline of eGFR in hypertensive patients with medication tended to be smaller than the decline in those without medication (0.94±1.41 vs. 1.09±1.42 mL/min per 1.73 m2 per year), this did not reach a statistical significance (p=0.213). Neither the number, classes of antihypertensive medications nor systolic blood pressure during the follow-up period did affect the average or yearly decline of eGFR in hypertensive patients.

Conclusions

As compared to normotensive subjects, eGFR was reduced and a yearly decrease in eGFR during the 5 years was accelerated in hypertensive patients. Although antihypertensive medication may reduce an accelerated age-dependent decline of kidney function in hypertension, observational period in this study was too short to clarify such beneficial effects of antihypertensive medications.

P1545Predictve factor for major adverse cardiovascular events in health check-up participants

Background/Introduction

Health check-up has been carried out for individual health management. One of its main objectives is the early detection and prevention of major adverse cardiovascular event (MACE).

Purpose

We investigated predictive factors for MACE among clinical test items in health check-up program.

Methods

A total of 13522 subjects (male=8140, 52.8±12.3 year-old at baseline), who visited our hospital for a health check-up between 2008 and 2015, were enrolled. After the baseline examination, they were followed up until December 2016 (median 1827 days) with the endpoint being the incident of MACE. The outcome was confirmed using a questionnaire at health check-up, medical record, telephone, or letter. Possible association between MACE and clinical test items including gender, age, waist circumference, blood pressure, kidney function, fasting plasma glucose, lipid profile, hemoglobin, electrocardiogram (ECG), smoking habit and alcohol consumption was investigated.

Results

During the follow-up period, MACE occurred in 196 subjects (3.03 per 1000 person-year), with the incidence being more frequent in male than female subjects (4.07 vs. 1.42 per 1000 person-year). Multivariate Cox-hazard analysis demonstrated that male gender (hazard ratio [HR] = 2.457, 95% confidence intervals [CI] = 1.498–4.028), age (HR = 1.056, 95% CI = 1.040–1.071), waist circumference (HR = 1.023, 95% CI = 1.004–1.042), systolic blood pressure (HR = 1.015, 95% CI = 1.005–1.024), hemoglobin (HR = 0.868, 95% CI = 0.758–0.994) and Sokolow–Lyon voltage in the ECG (HR = 1.227, 95% CI = 1.033–1.458) were significant predictors for MACE. However, in a model where B-type natriuretic peptide (BNP) was also added as an independent variable, BNP (HR = 2.593, 95% CI = 1.602–4.196) was the strongest predictor for MACE.

Conclusions

In participants underwent health check-up, systolic blood pressure and hemoglobin as well as age and gender were the risk factors of MACE. Appropriate control of blood pressure and treatment of anemia may be useful for the prevention of MACE. Measurement of BNP may give us additional important information associated with future MACE.

Effect of clinical signs, endocrinopathies, timing of surgery, hyperlipidemia, and hyperbilirubinemia on outcome in dogs with gallbladder mucocele

Gallbladder mucocele (GBM) is a common extra-hepatic biliary syndrome in dogs with death rates ranging from 7 to 45%. Therefore, the aim of this study was to identify the association of survival with variables that could be utilized to improve clinical decisions. A total of 1194 dogs with a gross and histopathological diagnosis of GBM were included from 41 veterinary referral hospitals in this retrospective study. Dogs with GBM that demonstrated abnormal clinical signs had significantly greater odds of death than subclinical dogs in a univariable analysis (OR, 4.2; 95% CI, 2.14-8.23; P<0.001). The multivariable model indicated that categorical variables including owner recognition of jaundice (OR, 2.12; 95% CI, 1.19-3.77; P=0.011), concurrent hyperadrenocorticism (OR 1.94; 95% CI, 1.08-3.47; P=0.026), and Pomeranian breed (OR, 2.46; 95% CI 1.10-5.50; P=0.029) were associated with increased odds of death, and vomiting was associated with decreased odds of death (OR, 0.48; 95% CI, 0.30-0.72; P=0.001). Continuous variables in the multivariable model, total serum/plasma bilirubin concentration (OR, 1.03; 95% CI, 1.01-1.04; P<0.001) and age (OR, 1.17; 95% CI, 1.08-1.26; P<0.001), were associated with increased odds of death. The clinical utility of total serum/plasma bilirubin concentration as a biomarker to predict death was poor with a sensitivity of 0.61 (95% CI, 0.54-0.69) and a specificity of 0.63 (95% CI, 0.59-0.66). This study identified several prognostic variables in dogs with GBM including total serum/plasma bilirubin concentration, age, clinical signs, concurrent hyperadrenocorticism, and the Pomeranian breed. The presence of hypothyroidism or diabetes mellitus did not impact outcome in this study.

Development of canine X-chromosome inactivation pattern analysis for the detection of cell clonality by incorporating the examination of the SLIT and NTRK-like family member 4 (SLITRK4) gene

X-chromosome inactivation pattern (XCIP) analysis can be used to assess the clonality of cell populations of various origin by distinguishing the methylated X chromosome from the unmethylated X chromosome. In this study, the utility of XCIP analysis was improved by incorporating the examination of AC dinucleotide repeats in SLIT and NTRK-like family member 4 (SLITRK4) gene into the previously reported CAG repeat examination of androgen receptor (AR) gene in dogs. The rate of heterozygosity when both genes were analysed (125/150, 83.3%) was higher than AR gene examination alone (86/150, 57.3%). Blood samples from heterozygous dogs in either AC-1 or AC-2 of SLITRK4 gene were examined for the corrected inactivation allele ratio (CIAR), resulting in the determination of a reference range of CIAR <3.8 in non-neoplastic cell/tissue samples. Using this analytical method, 49% (21/43) of neoplastic tissue samples from dogs showed a CIAR >3.8, indicating the presence of a clonal population. Through the present study, the availability of canine XCIP analysis was improved by incorporating the examination of the SLITRK4 gene, providing a highly useful laboratory examination system for the detection of the clonality of various cell/tissue samples in dogs.

Abstract P4-01-23: Clinical significance of serum PSA in breast cancer patients

Background: Recent preclinical data suggest that estrogen receptor (ER) positive breast cancer (BC), may switch from dependence on ER to androgen receptor (AR) as possible mechanism of resistance to ER-targeted endocrine therapy. AR dependency has also been suggested in a subset of ER-, AR+ BC. Based on these findings, clinical trials testing AR-targeting therapies in BC have been conducted. However, predictive markers for response to this type of therapies remain to be elucidated. PSA is the product of an androgen-responsive gene produced also in BC, and serum PSA (sPSA) could be detected in BC patients by a highly sensitive assay. Hypothesis:If sPSA reflects AR dependency of BC, it might be useful as a predictive marker for response to AR-targeting therapy. Methods:In this study, we investigated whether tumor-derived sPSA could be detected in BC patient, and if it might reflect tumor biology. In metastatic breast cancer (MBC) patients continuously observed, sPSA was evaluated monthly by CLEIA method (detection sensitivity ≥ 3 ng/L). Similarly, sPSA was evaluated at arbitrary points in non-BC control and point analysis BC group enrolled regardless of clinicopathological factor or treatment history. In the observational group, the relationship between change in disease condition and sPSA was analyzed. Next, correlations between sPSA and various clinicopathological factors were analyzed using combined data of point analysis group and initial sPSA value of observation group. In this study, 146 BC (26 observation group and 120 point analysis group) and 99 control were enrolled. Results: In the observational analysis, 5 cases showed sPSA change well reflected the disease condition, but not in other 5 cases. In remaining 16 cases, sPSA was undetectable or the observation period was insufficient (&lt;4m). In the point analysis, sPSA was detected in 28.3% and 28.1% in control and BC respectively. Although in pre-menopausal state, there was no significant difference in sPSA between control and BC (4.4 ± 6.98 ng/L vs 3.7 ± 5.5 ng/L), in post-menopausal state, sPSA was significantly higher in BC compared with control (0.7 ± 2.5 ng/L vs 64.6 ± 357.4 ng/L; P&lt;0.05). In analysis limited to post-menopausal BC, sPSA was higher in MBC (de-novo stage 4 and recurrence) compared with non-MBC (Stage0-3) (106.0 ± 457.2 ng/L vs 2.1 ± 8.5 ng/L; P&lt;0.05). Similarly, sPSA was higher in low ki-67 (&lt;20%) cases compared with high ki-67 (≥20%) (105.7 ± 510.8 ng/L vs 30.5 ± 173.7 ng/L; p&lt;0.05). There was no significant difference in sPSA due to histological type, ER or HER2 status and nuclear grade. In correlation analysis of quantitative data limited to post-menopausal MBC, sPSA was negatively correlated with Ki-67 (rS=-0.35, p&lt;0.05) and positively correlated with treatment line of previous endocrine therapy (rS=0.27, p&lt;0.05). It did not correlate with age, disease free interval, number of metastatic organs or treatment line of previous chemotherapy. Conclusion:Our data suggest that sPSA may be tumor-derived at least in post-menopausal MBC and may reflect some kind of tumor biological properties. These all findings justify further studies of the efficacy of sPSA as a predictive marker in AR-targeted therapy.

Citation Format: Hanamura T, Ohno K, Houkibara S, Murasawa H, Nakamura T, Watanabe H, Kaizuka M, Sawano S, Koyama H, Ito K-i. Clinical significance of serum PSA in breast cancer patients [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P4-01-23.

Double-layered antibiotic-loaded cement spacer as a novel alternative for managing periprosthetic joint infection: an in vitro study

BACKGROUND

Previous studies comparing antibiotic-loaded calcium phosphate cement to polymethylmethacrylate cement reported that although the former has higher elution volumes over a longer period, it is mechanically weak when used alone. To counter this problem, a double-layered antibiotic-loaded cement spacer in which calcium phosphate cement is coated with polymethylmethacrylate cement was created.

METHODS

In this study, we compared the double-layered spacer to the polymethylmethacrylate cement spacer in terms of eluent antibiotic concentration, bioactivity against methicillin-resistant Staphylococcus aureus, and mechanical strength. Double-layered and polymethylmethacrylate cement spacers that were loaded with vancomycin (VCM) were prepared and immersed in phosphate buffer for 84 days. To facilitate VCM elution from calcium phosphate cores in double-layered spacers, we also drilled multiple holes into the calcium phosphate layer from the spacer surface.

RESULTS

We found that VCM concentrations in double-layered spacer eluents were higher than those in polymethylmethacrylate cement spacer eluents. The double-layered spacer also had higher bioactivity than the polymethylmethacrylate cement spacer. Although the polymethylmethacrylate cement spacer eluent lost the ability to inhibit bacterial growth on day 56, the double-layered spacer eluent maintained this ability for the duration of our study. Finally, the double-layered spacer retained high mechanical strength throughout the study period.

CONCLUSIONS

The beneficial biomechanical and drug-eluting properties of the double-layered spacer might qualify it to serve as a promising biomaterial that could be used for managing periprosthetic joint infections.

Factors involved in phenoconversion of CYP3A using 4β-hydroxycholesterol in stable kidney transplant recipients

BACKGROUND

Phenoconversion is a phenomenon whereby some genotypic extensive metabolizers transiently exhibit drug metabolizing enzyme activity at similar level as that of poor metabolizers. Renal failure is known to decrease CYP3A activity in humans. Indoxyl sulfate, parathyroid hormone (PTH), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) have been reported to cause CYP3A downregulation in renal failure. We measured plasma concentrations of the above compounds in stable kidney transplant recipients, and evaluated their relations with phenoconversion of CYP3A evaluated by plasma concentration of 4β-hydroxycholesterol, a biomarker of CYP3A activity. Phenoconversion was defined as a genotypic extensive/intermediate metabolizer exhibiting CYP3A activity below the cutoff value that discriminates extensive/intermediate from poor metabolizers.

METHODS

Sixty-three Japanese kidney transplant recipients who underwent transplantation more than 180 days prior to the study were included. Morning blood samples were collected, and CYP3A5 polymorphism as well as plasma concentrations of 4β-hydroxycholesterol, indoxyl sulfate, intact-PTH, IL-6 and TNF-α were determined.

RESULTS

Significantly higher plasma 4β-hydroxycholesterol concentration was observed in recipients with CYP3A5*1 allele (n = 23) compared to those without the allele (n = 40), and the cut-off value was 40.0 ng/mL. Ten recipients with CYP3A5*1 allele exhibited CYP3A activity below 40.0 ng/mL (phenoconversion). Only plasma indoxyl sulfate concentration was significantly higher in recipients with CYP3A phenoconversion compared to those without phenoconversion.

CONCLUSIONS

These findings suggest that higher plasma indoxyl sulfate concentration may be involved in CYP3A phenoconversion. Dose adjustment of drugs metabolized by CYP3A may be needed in patients with CYP3A5*1 allele and high blood indoxyl sulfate.

Apolipoprotein E Gene Polymorphisms Affect the Efficacy of Thiazolidinediones for Alzheimer's Disease: A Systematic Review and Meta-Analysis

Although several studies have evaluated the efficacy of thiazolidinediones (TZD) for the treatment of Alzheimer's disease (AD), investigation of the impact of apolipoprotein E (ApoE) gene polymorphisms on the efficacy of TZD remains insufficient. We investigated the impact by conducting a systematic review and meta-analysis. MEDLINE, Cochrane Library, and Japana Centra Revuo Medicina were searched to identify relevant studies based on eligibility criteria. Mean differences (MD) of Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-Cog) total score with 95% confidence intervals (CI) were calculated for subgroups stratified by ApoE genotype. To evaluate the impact of ApoE gene polymorphisms, meta-regression analysis was also conducted to calculate the regression coefficient (Coef) of ApoE expression status with 95% CI. Three randomized controlled studies comparing rosiglitazone and placebo, with a total of 2381 subjects met the eligibility criteria. ApoE expression status was reported in 983 individuals (ApoE4-positive, 141; ApoE4-negative, 842). When compared to placebo, rosiglitazone significantly decreased ADAS-Cog score in ApoE4-negative individuals (MD, -1.37; 95% CI, -2.09 to -0.65), but significantly increased ADAS-Cog score in ApoE4-positive individuals (MD, 2.18; 95% CI, 0.52 to 3.85). The meta-regression analysis showed a significant association between efficacy and ApoE expression status (Coef, 3.55; 95% CI, 1.42 to 5.68). Although the present results should be interpreted with caution because of the limited number of studies, our findings suggest that ApoE gene polymorphisms impact the efficacy of rosiglitazone for AD patients. This finding would provide useful information for the development of new agents for AD.

Improving the Quality of Life of Patients With Severe Dysphagia by Surgically Closing the Larynx

OBJECTIVES:

The aim of this study was to elucidate the utility of the Kano method with surgical closure of the larynx by cricoid cartilage removal in improving quality of life in patients with severe dysphagia and their caregivers.

METHODS:

Nine patients with severe dysphagia who underwent the Kano method were evaluated for oral intake and activities of daily living using the functional oral intake scale and the Barthel index, respectively, as indices of quality of life. Additionally, nutritional status, inflammation, and postoperative complications were assessed. Furthermore, 7 family caregivers were queried regarding frequency of sputum suction, mood of family caregivers, and postoperative satisfaction.

RESULTS:

Functional oral intake scale and Barthel index scores as well as inflammation improved significantly after surgery ( P < .05). There were no severe complications or other complications requiring surgical intervention. The frequency of sputum suction was reduced postoperatively ( P < .05). The mood of family caregivers was significantly improved and satisfaction level was high postoperatively.

CONCLUSIONS:

Surgical closure of the larynx is an appropriate choice for patients with irreversible severe dysphagia and impaired articulation or vocal function because quality of life is improved for both patients and family caregivers and the satisfaction of family caregivers is sufficient.

An Unusual Invasive Ectopic Thymoma in the Thyroid and Anterior Mediastinum

An 81-year-old woman with a 2-year history of dysphagia detected a cervical mass. Computed tomography showed a thyroid tumor extending through the superior and anterior mediastinum. Analysis of an incisional biopsy specimen revealed a thymoma. Total resection of the thyroid and mediastinal tumor was performed. The thymoma invaded the anterior tracheal wall and left brachiocephalic vein. Pathologic examination revealed thymoma type B1 concomitant with B2 and B3 (World Health Organization classification), Masaoka IVb, and T3 N2 M0-IVb, with cervical lymph node metastasis. Clinicians must be cautious during radical operations for invasive ectopic thymomas.

Extensive first-principles molecular dynamics study on Li encapsulation into C60 and its experimental confirmation

The aim of increasing the production ratio of endohedral C₆₀ by impinging foreign atoms against C₆₀ is a crucial matter of the science and technology employed towards industrialization of these functional building block materials. Among these endohedral fullerenes, Li⁺@C₆₀ exhibits a wide variety of physical and chemical phenomena and has the potential to be applicable in areas spanning the medical field to photovoltaics. However, currently, Li⁺@C₆₀ can be experimentally produced with only ∼1% ratio using the plasma shower method with a 30 eV kinetic energy provided to the impinging Li⁺ ion. From extensive first-principles molecular dynamics simulations, it is found that the maximum production ratio of Li⁺@C₆₀ per hit is increased to about 5.1% (5.3%) when a Li⁺ ion impinges vertically on a six-membered ring of C₆₀ with 30 eV (40 eV) kinetic energy, although many C₆₀ molecules are damaged during this collision. On the contrary, when it impinges vertically on a six-membered ring with 10 eV kinetic energy, the production ratio remains at 1.3%, but the C₆₀ molecules are not damaged at all. On the other hand, when the C₆₀ is randomly oriented, the production ratio reduces to about 3.7 ± 0.5%, 3.3 ± 0.5%, and 0.2 ± 0.03% for 30 eV, 40 eV, and 10 eV kinetic energy, respectively. Based on these observations we demonstrate the possibility of increasing the production ratio by fixing six-membered rings atop C₆₀ using the Cu(111) substrate or UV light irradiation. In order to assess the ideal experimental production ratio, the ⁷Li solid NMR spectroscopy measurement is also performed for the multilayer randomly oriented C₆₀ sample irradiated by Li⁺ using the plasma shower method combined with inductively coupled plasma atomic emission spectroscopy (ICP-AES). Time-of-flight mass spectroscopy measurements are also performed to cross check whether Li⁺@C₆₀ molecules are produced in the sample. The resulting experimental estimate, 4% for 30 eV incident kinetic energy, fully agrees with our simulation results mentioned above, suggesting the consistency and accuracy of our simulations and experiments.

Induction of Diabetes Abolishes the Antithrombotic Effect of Clopidogrel in Apolipoprotein E-Deficient Mice

Patients with acute coronary syndrome with diabetes mellitus (DM) exhibit an impaired platelet inhibitory response to clopidogrel which is only partially understood. DM was induced by the administration of streptozotocin (STZ) to 9-week-old mice. The antithrombotic effects of clopidogrel (10 mg/kg/d, orally × 5 days) were determined using a FeCl ₃ -induced thrombosis model employing wild-type (WT), apolipoprotein E (apoE)-deficient, and diabetic apoE-deficient mice at 21 weeks. Antiplatelet effects were determined using flow cytometry. The antithrombotic effects of clopidogrel were similar in WT and apoE-deficient mice but were attenuated in diabetic apoE-deficient mice with the percent inhibition of thrombus area (µm ² ) by clopidogrel being 85.5% (WT mice), 75.0% (apoE-deficient mice), and 1.9% (diabetic apoE-deficient mice). The time to first occlusion and lumen stenosis also reflected a significant loss of the antithrombotic effects of clopidogrel in diabetic apoE-deficient mice. Ex vivo platelet activation, which was assessed using ADP-induced expression of activated glycoprotein IIb/IIIa, was completely inhibited by clopidogrel in these three groups of mice. In contrast, the effect of clopidogrel on the ex vivo expression of platelet P-selectin induced by protease-activated receptor 4–activating peptide was diminished in diabetic apoE-deficient mice compared with that in WT and apoE-deficient mice. These data suggest that diabetic apoE-deficient mice may serve as a useful model to better understand the impaired responses to clopidogrel in patients with DM, which may partially reflect a reduction of the effect of clopidogrel on thrombin-induced platelet activation.

Endoscopic Cytology for the Diagnosis of Chronic Enteritis and Intestinal Lymphoma in Dogs

Although cytology is a rapid diagnostic procedure in dogs, the cytologic criteria of endoscopic biopsies for chronic enteritis and intestinal lymphoma are not well defined. An immediate diagnosis using cytology would benefit patients by enabling prompt initiation of therapy. The objective of this study was to investigate the correlation between the results of endoscopic cytology and histopathology. In this study, 167 dogs with clinical signs of chronic gastrointestinal disease were included. On the basis of histopathology, the following diagnoses were determined: lymphocytic-plasmacytic enteritis in 93 dogs; eosinophilic enteritis in 5 dogs; small cell intestinal lymphoma in 45 dogs; and large cell intestinal lymphoma in 24 dogs. Two clinical pathologists retrospectively evaluated the endoscopic cytology of squash-smear preparations. The cytologic diagnoses of inflammation, small cell lymphoma, and large cell lymphoma were based on the severity of lymphocyte infiltration, the size of infiltrated lymphocytes, and eosinophil/mast cell infiltration. The clinical severity score was significantly increased along with the degree of lymphocyte infiltration evaluated by cytology. The cytologic diagnosis was in complete agreement with the histopathologic diagnosis in 136 of 167 (81.4%) cases. For the differentiation between enteritis and lymphoma, endoscopic cytology had a sensitivity of 98.6%, a specificity of 73.5%, a positive predictive value of 72.3%, and a negative predictive value of 98.6%. The log-rank test and Cox regression analysis showed that the results of cytology predicted the prognosis. These results suggest that endoscopic cytology is a useful technique to aid diagnosis of intestinal inflammation and lymphoma in dogs.

Increased number of IgG4-positive plasma cells in chronic rhinosinusitis

CONCLUSION

High levels of IgG4-positive plasma cells were observed in tissue samples from ∼30% of patients with chronic rhinosinusitis who satisfied the comprehensive diagnostic criteria for IgG4-related disease. Detection of increased numbers of IgG4-positive plasma cells in the nasal cavity or paranasal sinuses might not be sufficient to make a diagnosis of IgG4-related rhinosinusitis, and a comprehensive evaluation is required.

OBJECTIVES

This study aimed to clarify the clinicopathological characteristics of IgG4-positive plasma cells in patients with chronic rhinosinusitis.

METHOD

This study examined nasal mucosal specimens from 35 patients and assigned them to high-IgG4 and low-IgG4 groups based on infiltration of IgG4-positive plasma cells. It compared the pathological characteristics of the two groups, including the presence of fibrosis, phlebitis, hyperplasia of the nasal glands and infiltration of inflammatory cells.

RESULTS

No cases of chronic rhinosinusitis showed storiform fibrosis or obliterative phlebitis. The mean number of IgG4-positive plasma cells in samples from all patients was 29.8 ± 40.3/high-power field. Eleven of the 35 cases (31.4%) were classified as high-IgG4. Hyperplasia of the nasal glands was observed significantly more frequently in the high-IgG4 group than in the low-IgG4 group (p = .03).

Analysis of serum corticosteroid-induced alkaline phosphatase isoenzyme in dogs with hepatobiliary diseases

OBJECTIVE

To reveal the relationship between canine corticosteroid-induced alkaline phosphatase isoenzyme activity and hepatobiliary diseases.

MATERIALS AND METHODS

Retrospective analysis of the relationship between serum corticosteroid-induced alkaline phosphatase activity and diagnosis, serum cortisol concentration and alanine transferase activity in dogs with hepatobiliary diseases. Dogs with a history of glucocorticoid administration were excluded.

RESULTS

Seventy-two dogs with hepatobiliary diseases were analysed. The serum corticosteroid-induced alkaline phosphatase concentration was increased in dogs with hepatobiliary diseases. There was no correlation between serum cortisol concentration and serum corticosteroid-induced alkaline phosphatase percentage or activity.

CLINICAL SIGNIFICANCE

Dogs with hepatobiliary disease can exhibit high serum alkaline phosphatase activity even if the dogs have not been administrated glucocorticoids and the serum cortisol concentration is normal.

Evaluation of the severity of ulcerative colitis using endoscopic dual red imaging targeting deep vessels

Background and study aims Colonoscopies can predict long-term prognoses in patients with ulcerative colitis (UC). Recently, a new imaging technology has been developed that uses 3 types of illumination with center wavelengths of 540 nm, 600 nm, and 630 nm. The use of both the 600-nm and 630-nm lights (Dual red imaging; DRI) is critical for identifying blood vessels in deeper tissue. The aim of this study was to evaluate the usefulness of DRI for assessing the severity of inflammation in patients with UC. Patients and methods A total of 43 UC patients were retrospectively enrolled to evaluate the endoscopic severity of 112 colon segments, and Mayo endoscopic scores, DRI scores and the severity of inflammation on a visual analogue scale (VAS) were compared. The Mayo endoscopic scores, DRI scores, and histologic scores were evaluated, and the interobserver agreement on DRI scores among 5 investigators was also assessed. The usefulness of DRI scores for predicting prognoses was also assessed in patients with clinical remission. Results The DRI scores were closely correlated with the VAS for the severity of colonic inflammation (r = 0.96) and the histologic scores (r = 0.72 - 0.8). The DRI scores had a higher rate of interobserver agreement (κ values = 0.63 - 0.88) than the Mayo endoscopic scores (κ values = 0.44 - 0.59). Inter-observer agreement between 4 non-experts was also excellent (mean κ value = 0.76, range 0.63 - 0.82). The expected time until recurrence was significantly longer in patients with lower DRI scores (P < 0.01). Conclusion DRI can be used in patients with mild to moderate endoscopic severity because it targets the deep vascular pattern. The prognosis of UC can be predicted by assessing deep vessels using DRI.

Endoscopic Severity Predicts Long-Term Prognosis in Crohn's Disease Patients with Clinical Remission

INTRODUCTION

Mucosal healing has emerged as a desirable treatment goal in clinical practice for patients with Crohn's disease (CD). The aim of this study was to assess the relationship between endoscopic activity and the long-term prognosis of CD using simple endoscopic score for Crohn's disease (SESCD) and Rutgeerts' score.

METHODS

We conducted a cohort study in clinical practice at a single center. Among CD patients who underwent colonoscopy between July 2008 and June 2011 at our hospital, 131 patients with clinical remission were selected, and the patients were divided into 2 groups: a non-surgical group (n = 84) and a surgical group (n = 47). The primary endpoint of this study was to assess the associations between variables and clinical relapse after endoscopic procedures. The cut-off levels of SESCD or Rutgeerts' score for the prediction of relapse were also assessed in patients with clinical remission.

RESULTS

In the non-surgical group, SESCD and C-reactive protein at baseline were significantly higher in patients who had clinical recurrence than in patients who maintained remission. A factor of SESCD ≤2 was independently associated with sustained remission, even in patients with clinical remission. In the surgical group, patients with Rutgeerts' scores ≤1 had significantly prolonged clinical remission compared to patients with Rutgeerts' scores ≥3.

CONCLUSION

A cut-off value of SESCD ≤2 and a Rutgeerts' score ≤1 enabled the prediction of long-term prognosis. These cut-off values could be used in clinical trials of endoscopic remission from the point of view of the clinical outcomes of CD.

Genetic and epigenetic aberrations of p16 in feline primary neoplastic diseases and tumor cell lines of lymphoid and non-lymphoid origins

The p16 gene acts as a tumor suppressor by regulating the cell cycle and is frequently inactivated in human and canine cancers. The aim of this study was to characterize genetic and epigenetic alterations of the p16 in feline lymphoid and non-lymphoid malignancies, using 74 primary tumors and 11 tumor cell lines. Cloning of feline p16 and subsequent sequence analysis revealed 11 germline sequence polymorphisms in control cats. Bisulfite sequencing analysis of the p16 promoter region in a feline lymphoma cell line revealed that promoter methylation was associated with decreased mRNA expression. Treatment with a demethylating agent restored mRNA expression of the silenced p16. PCR amplification and sequencing analysis detected homozygous loss (five tumors, 6.7%) and a missense mutation (one tumor, 1.4%) in the 74 primary tumors analyzed. Methylation-specific PCR analysis revealed promoter methylation in 10 primary tumors (14%). Promoter methylation was frequent in B cell lymphoid tumors (7/21 tumors, 33%). These genetic and epigenetic alterations were also observed in lymphoma and mammary gland carcinoma cell lines, but not detected in non-neoplastic control specimens. These data indicate that molecular alterations of the p16 locus may be involved in the development of specific types of feline cancer, and warrant further studies to evaluate the clinical value of this evolutionarily-conserved molecular alteration in feline cancers.