Optimal Timing of Intravenous Acetaminophen Administration for Postoperative Analgesia

OBJECTIVE

Acetaminophen (APAP) is widely used as an analgesic for postoperative pain relief. However, the pharmacokinetic-pharmacodynamic (PK-PD) properties of intravenous APAP administration remain unclear. We developed a PK-PD model in adult volunteers.

METHODS

APAP (1 g) was intravenously administered to 15 healthy volunteers. The pain equivalent current (PEC) was then measured using the pulse current, corresponding to the quantitative value of pain perception. The PK model was developed using a 2-compartment model, and the PD model was developed using a linear model and an effect compartment model.

RESULTS

APAP plasma concentration peaked just administration, whereas PEC significantly increased at 90 minutes and lasted through the experimental period (300 minutes). APAP plasma concentrations and PEC were processed for use in the PK-PD model. The developed PK-PD model delineates the analgesic effect profile, which peaked at 188 minutes and lasted until 327 minutes.

CONCLUSION

We developed the PK/PD model for APAP administered intravenously. The analgesic effect can be expected ∼90 minutes after administration and to last >5 hours. It is suggested that APAP be administered ∼90 minutes prior to the onset of anticipated postoperative pain.

Evaluation of in vitro transdermal permeation, mass spectrometric imaging, and in vivo analgesic effects of pregabalin using a pluronic lecithin organogel formulation in mice

In clinical practice, pregabalin is orally administered for neuropathic pain, but causes severe central nervous system side effects, such as dizziness, which results in dose limitation or discontinuation. To reduce the central side effects of pregabalin, we developed four pregabalin preparations for transdermal application: 0.4% aqueous solution, pluronic lecithin organogel (PLO gel), hydrophilic cream, and lipophilic cream. Transdermal permeabilities of pregabalin among the four formulations were compared in vitro using hairless mouse skin. The longitudinal distribution of pregabalin within the skin was analyzed using mass spectrometric (MS) imaging. Furthermore, the in vivo analgesic effects of the formulations were evaluated using the von Frey filament test in a mouse model of diabetic neuropathy (DN). The PLO gel showed the highest permeability of pregabalin, followed by the aqueous solution, and no permeation was observed in the two cream formulations. The MS imaging analysis showed that pregabalin was distributed up to the dermis in the PLO gel 1 h after application, while the aqueous solution was distributed near the epidermis. A significant analgesic effect (p < .05) was observed 1.5 h after PLO gel application in the DN model mice, but the aqueous solution had no effect. This study indicated for the first time that pregabalin penetrated beyond the skin epidermis up to the dermis, from the PLO gel formulation, and that the application of this formulation exhibited an in vivo analgesic effect in the mouse model of DN.

Association Between Immune-related Adverse Events and Clinical Outcome Following Nivolumab Treatment in Patients With Metastatic Renal Cell Carcinoma

BACKGROUND/AIM

Immune-related adverse events (irAEs) are associated with the efficacy of immune-checkpoint inhibitors in patients with melanoma and non-small cell lung cancer. We therefore evaluated the relationship between irAEs and nivolumab efficacy against metastatic renal cell carcinoma.

PATIENTS AND METHODS

The medical records of 53 consecutive patients were reviewed and analyzed.

RESULTS

Median overall survival was significantly better in patients who showed irAEs at any time compared to patients without irAEs (p=0.013). We identified irAEs in 24 of 53 patients (45.3%), including four patients (7.5%) with grade 3 events. Multivariate analysis also revealed that risk factors for the onset of irAEs were positively associated with a platelet-to-lymphocyte ratio <156 before nivolumab treatment (p=0.006).

CONCLUSION

Development of irAEs was associated with survival outcomes of nivolumab treated patients with metastatic renal cell carcinoma.

The selective cytotoxicity of silver thiosulfate, a silver complex, on MCF-7 breast cancer cells through ROS-induced cell death

BACKGROUND

Silver is a transition metal that is known to be less toxic than platinum. However, only few studies have reported the anticancer effects of some silver complexes and their possibility as an alternative to platinum complex. This study investigated the anticancer effects of the silver thiosulfate complex (STS), [Ag(S₂O₃)₂]^3-, consisting of silver and sodium thiosulfate.

METHODS

In vitro cytotoxic activity of STS was investigated comparatively in human cancer cell lines (K562 and MCF-7) and normal human cells (mesenchymal stem cells and mammary epithelial cells). For its anticancer effects, cell cycle, mode of cell death, morphological changes, and accumulation of intracellular ROS and GSH were evaluated in MCF-7 to provide mechanistic insights.

RESULTS

STS showed a concentration-dependent cytotoxicity in MCF-7 cell, which was abolished by pretreatment with N-acetylcysteine, suggesting ROS accumulation by STS. Moreover, STS caused cell cycle arrest at the G1 phase, decrease in the GSH levels, and morphological changes in MCF-7. Direct measurement of ROS demonstrated the elevation of intracellular ROS accumulation in cancer cells treated with STS; however, neither cytotoxicity nor ROS accumulation was observed in normal human cells.

CONCLUSION

The results obtained here are the first evidence to show that STS exhibited an anticancer activity through ROS-induced mechanisms, and that its cytotoxicity is highly selective to cancer cells. The results of the present study warrant further investigation on the detailed mechanism of STS actions, as well as its in vivo effectiveness and safety for clinical application.

Effects of dosing frequency on the clinical efficacy of ampicillin/sulbactam in Japanese elderly patients with pneumonia: A single-center retrospective observational study

This study sought to investigate whether dosing frequency (the number of doses per day) affects the antimicrobial efficacy and safety of ampicillin/sulbactam (ABPC/SBT) in Japanese elderly pneumonia patients treated with ABPC/SBT at 6 g/day. This was a retrospective observational study that included hospitalized elderly patients (aged ≥75 years, 10 ml/min ≤CLcr <50 ml/min) who received 3 g every 12 h (BID; n = 61) or 1.5 g every 6 h (QID; n = 45) for the treatment of pneumonia. The primary endpoint was clinical response, assessed by measuring body temperature, white blood cell count, and C‐reactive protein levels. Pharmacokinetic and pharmacodynamic simulations were conducted insilico to rationalize the clinical findings. The clinical response rates (extremely effective and effective) in the BID and QID groups were 36.1% and 55.6%, respectively (p = .0459). QID tended to be more effective in patients with gram‐negative rods detected (p = .0563). According to the simulated minimum plasma ABPC concentrations at steady state for BID and QID were 2.5 and 7.3 μg/ml, respectively (p < .0001). Based on the simulated time above minimum inhibitory concentration (MIC), pharmacological (not clinical) efficacy was predicted to be higher with QID. Both groups had similar safety profiles. The main adverse event in both groups was liver damage. The present retrospective survey demonstrated that ABPC/SBT treatment for elderly patients with pneumonia and renal dysfunction was more effective with QID than with BID. Therefore, the QID regimen is worthy of consideration to improve the clinical outcomes of ABPC/SBT therapy in the present patient population.

Associations among plasma concentrations of regorafenib and its metabolites, adverse events, and ABCG2 polymorphisms in patients with metastatic colorectal cancers

PURPOSE

The association between the pharmacokinetics and pharmacodynamics of regorafenib, a multiple tyrosine kinase inhibitor, remains unclear. This study assessed the trough plasma concentrations (C_trough) of regorafenib and its N-oxide (M2) and N-oxide/desmethyl (M5) metabolites, and evaluated the associations among these levels, adverse events, and pharmacokinetic-related genetic polymorphisms in patients with metastatic colorectal cancer.

METHODS

The C_trough levels of regorafenib and its metabolites were assessed in a single-center, prospective, observational study, 7 days after the initial treatment. The correlation between those values and adverse events was then examined. In addition, the genetic polymorphisms of ABCG2, SLCO1B1, and UGT1A9 were determined and evaluated for associations with the levels of regorafenib, M2, and M5.

RESULTS

We analyzed 43 patients who received regorafenib 40-120 mg/day; among them, 35 patients started at 120 mg/day. With regard to bilirubin increase, the C_trough values of regorafenib were significantly higher in the group with grade ≥ 2 than in groups with grades 0 and 1 (p = 0.010). The M5 C_trough levels were significantly associated with the severity of hypertension or rash (p < 0.05). In a multivariate analysis, the M5 C_trough values and age were significant predictors of severe rash. Lastly, significant differences were noted in the M5 concentration-to-dose ratio values between the patients with ABCG2 421A/A and ABCG2 421C/A or C/C polymorphisms (p = 0.035).

CONCLUSION

This study showed that the C_trough of regorafenib was associated with bilirubin increase, and also clarified for the first time that the C_trough of M5 was significantly correlated with hypertension and severe rash.

Nonlinear Disposition and Metabolic Interactions of Cannabidiol Through CYP3A Inhibition In Vivo in Rats

Introduction: Cannabidiol (CBD) is known to affect the pharmacokinetics of other drugs through metabolic inhibition of CYP2C19 and CYP3A4. However, there is a lack of in vivo evidence for such drug interactions. Therefore, we investigated the saturability of CBD metabolism and CBD-drug interactions through inhibition of CYP3A in vivo. Materials and Methods: A nanoemulsion formulation of CBD (CBD-NE) was orally administered to rats at doses of 5, 10, 25, and 50 mg/kg, and plasma concentrations of CBD were measured by using liquid chromatography-tandem mass spectrometry (LC-MS/MS) to examine the dose-dependency of CBD exposure (area under the curve [AUC]). To examine the effect of a CYP3A inhibitor on CBD pharmacokinetics, rats were orally pretreated with 50 mg/kg ketoconazole (KCZ), a strong CYP3A inhibitor, before oral administration of CBD-NE at doses of 10 and 50 mg/kg, and plasma concentrations of CBD were measured using LC-MS/MS. Moreover, 13C-erythromycin was orally administered following administration of either NE (without CBD), as a control, or CBD-NE at 1, 10, and 50 mg/kg, and 13C-breath response was measured by using an infrared analyzer. Results: After administration of various doses of the nanoemulsified CBD formulation to rats, the exposure of CBD (i.e., the AUC calculated from the plasma concentration-time profile) increased in a greater than dose-proportional manner, especially at doses above 10 mg/kg. The AUC and maximum plasma concentration (Cmax) of CBD after oral administration of CBD-NE (10 mg/kg) increased approximately three times by the coadministration of KCZ. Moreover, according to the CBD-induced changes of 13C-breath response, the metabolism of 13C-erythromycin was shown to be inhibited by CBD at doses of 10 and 50 mg/kg, but not at 1 mg/kg. Conclusions: Nonlinear disposition and CYP-mediated drug interactions of CBD at doses exceeding 10 mg/kg were demonstrated for the first time in vivo in rats. Given the present results, it is proposed that caution for dose-dependent drug interactions should be considered for CBD.

[Rubric Assessment for Pharmacotherapy in Spiral Curriculum: Development and Usefulness Evaluation]

A requirement, which students must satisfy, for a diploma at the Showa University School of Pharmacy is the ability to "plan, practice, and assess pharmacotherapy". To continuously assess the ability of students to meet this requirement and to provide patients with proper pharmacotherapy during student clinical rotations, we formulated the "Rubric assessment for pharmacotherapy" and evaluated its usefulness in tutorial learning classes. Clinical pharmacy faculty members created the rubric based on the Subjective, Objective, Assessment, and Plan (SOAP) note guidelines of the university. Third- (2016) and fourth-year students (2017) were required to self-assess their SOAP notes to analyze six clinical cases using the rubric. The rubric consists of three domains: (1) Evaluation of patient condition, (2) Proposal of pharmacotherapy, and (3) Plan for an assessment of pharmacotherapy. The rubric comprises 31 subdomains and is evaluated according to four levels of performance. In this study, 978 rubric sheets that were used by students to evaluate their own SOAP notes were analyzed. We found that the students were able to continuously self-assess their performance using the rubric while continuously improving their achievement level (p<0.05). The results of this study suggest that rubric assessments may be used as a tool for supporting students to plan, practice, and assess pharmacotherapy.

AB0612 SHORT-TERM REVERSIBLE IMPROVEMENT IN EARLY-PHASE ELEMENTS OF NAILFOLD CAPILLARY ABNORMALITIES IN PATIENTS WITH SYSTEMIC SCLEROSIS BY INTRAVENOUS CYCLOPHOSPHAMIDE (IVCY)

Background:

Nailfold capillary abnormalities are one of representative signs in systemic sclerosis (SSc). However, previous reports about changes in nailfold capillary by immunosuppressive therapy have been limited. Especially, there have been no reports about short-term changes in nailfold capillary abnormalities.

Objectives:

To clarify whether intravenous cyclophosphamide (IVCY) treatment for SSc patients can improve nailfold capillary abnormalities in half a year.

Methods:

Among patients diagnosed as having SSc according to the 2013 ACR/EULAR classification criteria at our hospital from May 2018 to December 2019, those who treated with IVCY for interstitial lung disease (ILD) were consecutively registered. All patients received IVCY six times. Nailfold capillary abnormalities on eight fingers including both second to the fifth fingers were observed with a nailfold videocapillaroscopy (NVC). Each finger was evaluated for enlarged capillary, giant capillaries, hemorrhage, loss of capillary, disorganization of the vascular array, and capillary ramification. Quantitative scoring was performed on a scale of 0 to 3 in accordance with the ratio of each of them. NVC tests were evaluated before IVCY treatment intervention and after IVCY. In all cases, the evaluation of NVC after IVCY treatment was performed 6 months after the administration day. Skin changes were evaluated by modified Rodnan’s total skin thickness score (mRSS) at performing NVC. Anti-centromere antibodies, anti-Scl-70 antibodies, anti-RNA polymerase III, and anti-RNP antibodies were measured. Pulmonary function tests (PFTs) including forced vital capacity (FVC) and diffusing capacity of the lung carbon monoxide (DLCO) were performed before and after IVCY. The statistical significance of the differences between means of two groups was evaluated by paired t-test. A p level of 0.05 or less was considered statistically significant.

Results:

Five patients were included. The mean age was 59 years and 4 patients were female (80%). High dose corticosteroids were used in 2 patients (40%). Anti-RNA polymerase III was positive in 2 patients (40%), anti-Scl-70 antibody was positive in 1 (20%), and negative test for any specific antibodies was in 2 (40%). Changes in NVC scores, which were total scores of 8 fingers, were as follows: Enlarged; 13.2±4.8 to 6.4±5.9 (p=0.018), Giant; 7.0±5.7 to 1.6±1.1 (p=0.0314), Hemorrhage; 8.4±6.2 to 3.2±2.3 (p=0.0274), Loss; 4.0±2.5 to 0.6±1.3 (p=0.0288), Disorganization; 0.6±0.9 to 1.0±1.0 (p=0.7065), Ramification; 0.6±0.9 to 0.8±1.8 (p=0.5730). (Table) After IVCY treatment, mRSS reduced in 4 cases (80%). Changes in mRSS scores were as follows: 18.8±8.3 to 12.4±13.3 (p=0.0677). The cases with improved mRSS and those with improved NVC findings were consistent. The mean FVC before and after IVCY was 2077 ml and 2062 ml, respectively. The mean DLCObefore and after IVCY was 9.88 mL/min/mmHg and 9.58 mL/min/mmHg, respectively.

Conclusion:

Nailfold capillary abnormalities in patients with SSc could be improved in half a year with IVCY. Especially, early phase elements including enlargement, giant, and hemorrhage were specifically reversible.

Table.No.(E)(G)(H)(L)(D)(R)mRSS121→1416→319→70→00→20→014→9212→34→26→14→02→11→015→1314→118→26→27→00→00→410→5410→46→18→34→30→22→025→1259→01→03→35→01→00→030→35mean ± SD13.2±4.87.0±5.78.4±6.24.0±2.50.6±0.90.6±0.918.8±8.36.4±5.91.6±1.13.2±2.30.6±1.31.0±1.00.8±1.812.4±13.3p-value0.0180.03140.02740.02880.70650.57300.0677

E: enlarged, G: giant, H: hemorrhage, L: loss, D: disorganization, R: ramification.

The table shows the total of eight points for each finding in the NVC test. The previously described values are before treatment and the later values are after treatment.

Disclosure of Interests:

Tomohiro Sugimoto: None declared, Shintaro Hirata Grant/research support from: Eli Lilly, Consultant of: Bristol-Myers Squibb, UCB, Paid instructor for: AbbVie, Eisai, Tanabe-Mitsubishi, Speakers bureau: AbbVie, Eisai, Tanabe-Mitsubishi, Astellas, Ayumi, Bristol-Myers Squibb, UCB, Chugai, Eli Lilly, Janssen, Kissei, Sanofi, Takeda, Hiroki Kohno: None declared, Hirofumi Watanabe: None declared, Yusuke Yoshida Grant/research support from: Astellas, Paid instructor for: Astellas, Tanabe Mitsubishi, Sanofi, Novartis, GlaxoSmithKline, Eli Lilly, Bristol-Myers Squibb, Chugai, Asahikasei, Eisai, Janssen, Speakers bureau: Astellas, Tanabe Mitsubishi, Sanofi, Novartis, GlaxoSmithKline, Eli Lilly, Bristol-Myers Squibb, Chugai, Asahikasei, Sho Mokuda: None declared, Eiji Sugiyama Grant/research support from: AbbVie, Astellas, Ayumi, Kissei, Pfizer, Sanofi, Takeda, Tanabe-Mitsubishi, Bristol-Myers Squibb, Chugai, Eisai, Eli Lilly, Speakers bureau: AbbVie, Astellas, Ayumi, Kissei, Pfizer, Sanofi, Takeda, Tanabe-Mitsubishi, Bristol-Myers Squibb, Chugai, Eisai, Eli Lilly, Actelion

AB0452 PREDICTIVE FACTORS FOR INSUFFICIENT RESPONSE TO INITIAL TREATMENT OR RECURRENCE IN PATIENTS WITH LUPUS ENTERITIS

Background:

Lupus enteritis (LE) is a rare but well-known complication of systemic lupus erythematosus (SLE). However, little knowledge about risk factors for insufficient response to initial treatment or recurrence have been reported.

Objectives:

To identify prognostic factors associated with poor response in patients with LE.

Methods:

Patients diagnosed as having LE at our hospital were consecutively registered from January 2009 to October 2019. The diagnosis of LE was made according to the criteria of BILAG 2004 which is defined as either vasculitis or inflammation of small or large bowel with supportive imaging and/or biopsy findings. Poor response was defined as insufficient response to initial therapy or relapse. We retrospectively compared clinical characteristics collected from medical records of the patients with good vs. poor response, using a non-parametric Wilcoxon signed-rank test for numerical variables and Fisher’s exact test for categorical variables.

Results:

A total of 12 patients (16 episodes) diagnosed with LE were reviewed. The median age was 44.5 years and 11 were females. Six patients had a history of SLE (median disease duration; 3.0 years), of which 4 had a history of LE prior to the study period. And in the remaining 6 patients, LE was the primary symptom (Table 1). The comorbidities were 4 lupus cystitis, 1 biopsy-proven lupus nephritis, 1 pseudo-obstruction and 1 protein-losing enteropathy. Computed Tomography (CT) imaging of all 16 episodes showed small bowel wall thickening. Dilatation of intestine was observed in 81.3%, ascites in 81.3%, comb sign in 80.0% and target sign in 62.5%. When comparing clinical characteristics between the groups revealed that CT findings were similar in both groups, however serum CH50 levels (median (interquartile ranges (IQR)) 37.2 (25.3-46.9) U/mL vs 17.6 (7.1-21.4) U/mL, p=0.0095) were significantly lower in poor response group. Furthermore, patients who initiated glucocorticoids (GCs) at a lower dose (less than or equal to 0.6mg/kg prednisolone equivalent dose (PEQ)) was significantly more frequent in poor response group (Table 2).

Table 1.

Baseline demographics and outcomes of LE patients

VariablesN=12DemographicsFemale (%)91.7Age (yrs), median (IQR)44.5 (34.0-47.5)SLE duration (yrs), median (IQR)3.0 (0-9.0)Baseline therapyPrednisolone (mg), median (IQR)7.0 (0-10.5)Cyclosporine (%)16.7Azathioprine (%)8.3Mycophenolate mofetil (%)8.3Tacrolimus (%)8.3OutcomesFollow-up period (yrs), median (IQR)4.0 (1.9-5.0)Poor response to initial therapy (%)33.3Recurrence (%)33.3Need for surgical intervention (%)8.3Death (%)0Table 2.

Comparison of baseline characteristics and initial treatment between LE patients with good vs. poor response

VariablesGood response(N=10)Poor response(N=6)p valueComorbiditiesLupus cystitis (%)30.033.31.0Lupus nephritis (%)016.70.38CT findingsMaximum external diameterof small intestine (mm), median (IQR)30.8 (22.2-37.9)25.3 (19.4-29.0)0.083Colon involvement (%)30.066.70.30Dilatation of intestine (%)90.066.70.52Ascites (%)90.066.70.52Comb sign (%)90.066.70.52Target sign (%)70.050.00.61Laboratoryfindingsanti-dsDNA Ab (IU/mL), median (IQR)5.4 (1.6-12.6)10.1 (3.8-111.5)0.17CH50 (U/mL), median (IQR)37.2 (25.3-46.9)17.6 (7.1-21.4)0.0095C4 (mg/dL), median (IQR)16.0 (10.5-27.3)10.0 (10.0-13.8)0.11C3 (mg/dL), median (IQR)66.0 (56.8-79.8)46.5 (33.0-58.3)0.10Initial treatmentLess than or equal to 0.6mg/kg PEQ (%)10.066.70.036Intravenous cyclophosphamide10.016.71.0

Conclusion:

Lower level of CH50 and initial treatment with GCs at a lower dose were identified as prognostic factors associated with poor response to initial therapy or recurrence in LE.

Disclosure of Interests: :

Yusuke Yoshida Grant/research support from: Astellas, Paid instructor for: Astellas, Tanabe Mitsubishi, Sanofi, Novartis, GlaxoSmithKline, Eli Lilly, Bristol-Myers Squibb, Chugai, Asahikasei, Eisai, Janssen, Speakers bureau: Astellas, Tanabe Mitsubishi, Sanofi, Novartis, GlaxoSmithKline, Eli Lilly, Bristol-Myers Squibb, Chugai, Asahikasei, Tomohiro Sugimoto: None declared, Hiroki Kohno: None declared, Hirofumi Watanabe: None declared, Sho Mokuda: None declared, Shintaro Hirata Grant/research support from: Eli Lilly, Consultant of: Bristol-Myers Squibb, UCB, Paid instructor for: AbbVie, Eisai, Tanabe-Mitsubishi, Speakers bureau: AbbVie, Eisai, Tanabe-Mitsubishi, Astellas, Ayumi, Bristol-Myers Squibb, UCB, Chugai, Eli Lilly, Janssen, Kissei, Sanofi, Takeda, Eiji Sugiyama Grant/research support from: AbbVie, Astellas, Ayumi, Kissei, Pfizer, Sanofi, Takeda, Tanabe-Mitsubishi, Bristol-Myers Squibb, Chugai, Eisai, Eli Lilly, Speakers bureau: AbbVie, Astellas, Ayumi, Kissei, Pfizer, Sanofi, Takeda, Tanabe-Mitsubishi, Bristol-Myers Squibb, Chugai, Eisai, Eli Lilly, Actelion

Development of a Novel Nano-emulsion Formulation to Improve Intestinal Absorption of Cannabidiol

BACKGROUND

Cannabidiol (CBD) is highly lipophilic, and its oral bioavailability is known to be very low in humans. In this study, we developed a novel nanoemulsion preparation of CBD (CBD-NE) to improve the poor solubility and absorption of CBD. The pharmacokinetic profiles of CBD in rats were evaluated after oral administrations of CBD oil and CBD-NE, and the effect of bile secretion on CBD absorption was also evaluated.

METHODS

The CBD-NE formulation developed in this study consisted of vitamin E acetate, ethanol, Tween-20, and distilled water (1.7/3.8/70/24.5, w/w%). A CBD oil formulation (CBD oil, control) 100 mg/kg or CBD-NE 50 mg/kg was orally administered to rats, and the blood samples were collected over time. Moreover, the CBD oil or CBD-NE was orally administered to bile-fistulated rats, and the pharmacokinetic profiles of CBD were also evaluated. CBD concentrations in plasma were measured using LC-MS/MS.

RESULTS

The particle size of CBD-NE was 35.3 ± 11.8 nm. Mean Tmax of CBD-NE was shortened significantly by the factor of 3 (from 8.00 to 2.40 h, p < 0.001) and AUC0-∞/dose increased by 65% (from 0.272 ± 0.045 to 0.448 ± 0.087 h L/kg) compared with CBD oil. AUC0-∞/dose and Cmax/dose after oral administration of CBD oil were significantly reduced by the factor of 27 and 23 (p < 0.05 and p < 0.01), respectively, in bile-fistulated rats compared with the untreated rats. In contrast, all pharmacokinetic parameters after oral administration of CBD-NE were not significantly different between the untreated and bile-fistulated rats. Therefore, these results demonstrated that conventional CBD oil formulation but not CBD-NE requires bile-mediated micelle formation.

CONCLUSIONS

The novel NE formulation developed in this study successfully improved the absorption of CBD regardless of bile secretion. The newly developed oral CBD-NE preparation could be useful to achieve a more stable and quicker onset of action by CBD.

Large-vessel vasculitis associated with PEGylated granulocyte-colony stimulating factor

A 71-year-old female with advanced endometrial cancer was treated with pegfilgrastim. She developed a fever within seven days, and contrast-enhanced computed tomography scans repeated within three days revealed rapidly progressive thickening of the aortic wall. When clinicians administer PEGylated granulocyte-colony stimulating factor (G-CSF) to cancer patients, drug-associated vasculitis should be suspected. This report discusses the manifestation of G-CSF-associated large-vessel vasculitis (LVV).

Tumour necrosis factor α augments the inhibitory effects of CTLA-4-Ig on osteoclast generation from human monocytes via induction of CD80 expression

Cytotoxic T lymphocyte antigen-4-immunoglobulin (CTLA-4-Ig) exerts anti-rheumatic action via negative regulation of the co-stimulation process between antigen-presenting cells and T cells. CTLA-4-Ig also binds to CD80/CD86 on monocytes of osteoclast precursors. However, little is known about the effect of CTLA-4-Ig on osteoclastogenesis in rheumatoid arthritis (RA). In this study we evaluated the effects of CTLA-4-Ig on osteoclast generation from human blood monocytes (PBM) and rheumatoid synovial fluid monocytes (RSFM). Highly purified monocytes were cultured with receptor activator of nuclear factor kappa-B ligand (RANKL) and macrophage colony-stimulating factor (M-CSF) in the presence of CTLA-4-Ig. CTLA-4-Ig inhibited RANKL-induced osteoclast generation in PBM and RSFM, as determined by tartrate-resistant acid phosphatase (TRAP) staining and bone resorption assay using osteo assay surface plates. In addition, CTLA-4-Ig reduced the gene and protein expressions of nuclear factor of activated T cells, cytoplasmic 1 (NFATc1) and cathepsin K during osteoclastogenesis. Furthermore, CTLA-4-Ig significantly inhibited cell proliferation during osteoclastogenesis. Interestingly, the gene expression of indoleamine 2,3-dioxygenase-1, an inducer of apoptosis, was enhanced by CTLA-4-Ig. We next examined the effect of tumour necrosis factor (TNF)-α, a major inflammatory cytokine in rheumatoid synovium, on the expression of CD80 and CD86 by flow cytometric analysis. TNF-α potently induced the surface expression of CD80, which is known to have much higher affinity to CTLA-4-Ig than CD86, and this induction was observed at mRNA levels. Interestingly, freshly prepared rheumatoid synovial monocytes also expressed CD80 as much as TNF-α-treated PBM. Furthermore, TNF-α enhanced CTLA-4-Ig-induced inhibition of osteoclastogenesis and cell proliferation. Taken together, the TNF-α-induced CD80 may augment CTLA-4-Ig-induced inhibition of osteoclastogenesis, suggesting that CTLA-4-Ig potently inhibits osteoclast differentiation and protects bone destruction in rheumatoid inflamed joints.

Association of Hand-Foot Skin Reaction with Regorafenib Efficacy in the Treatment of Metastatic Colorectal Cancer

PURPOSE

Hand-foot skin reaction (HFSR) can deteriorate quality of life in patients receiving regorafenib. Cutaneous toxicity is a main adverse effect of multikinase inhibitors and has also been associated with clinical outcome. This study assessed the association between the antitumor efficacy of regorafenib and HFSR in patients with metastatic colorectal cancer (mCRC).

METHODS

Patients who received regorafenib at 160 mg/day during the first 3 weeks of each 4-week cycle were divided into subgroups based on whether they developed HFSR between May 2013 and October 2015. Estimates of overall survival and progression-free survival were calculated using the Kaplan-Meier method.

RESULTS

Ninety-seven patients received at least one dose of regorafenib in this retrospective study. Of these patients, 81.4% (n = 79) experienced HFSR of any grade, and 34.0% (n = 33) had grade 3 HFSR. Among those patients with HFSR at any time during the study, 68.0% (n = 66) underwent the first HFSR event (any grade) during cycle 1. Both overall survival and progression-free survival were improved in patients who had HFSR grade ≥2 at any time compared with those who had HFSR grade ≤1. Multivariate logistic regression analysis revealed a history of HFSR grade ≥2 induced by capecitabine as a significant risk factor for severe HFSR (grade ≥2).

CONCLUSIONS

Patients with mCRC treated using regorafenib who experienced severe HFSR showed better overall survival than patients without severe HFSR. Severe HFSR may offer an early surrogate marker for the efficacy of regorafenib in patients with mCRC.

The induced RNA-binding protein, HuR, targets 3'-UTR region of IL-6 mRNA and enhances its stabilization in periodontitis

RNA-binding proteins (RBPs) regulate mRNA stability by binding to the 3'-untranslated region (UTR) region of mRNA. Human antigen-R (HuR), one of the RBPs, is involved in the progression of diseases, such as rheumatoid arthritis, diabetes mellitus and some inflammatory diseases. Interleukin (IL)-6 is a major inflammatory cytokine regulated by HuR binding to mRNA. Periodontal disease (PD) is also an inflammatory disease caused by elevations in IL-6 following an infection by periodontopathogenic bacteria. The involvement of HuR in the progression of PD was assessed using in-vitro and in-vivo experiments. Immunohistochemistry of inflamed periodontal tissue showed strong staining of HuR in the epithelium and connective tissue. HuR mRNA and protein level was increased following stimulation with Porphyromonas gingivalis (Pg), one of the periodontopathogenic bacteria, lipopolysacchride (LPS)-derived from Pg (PgLPS) and tumour necrosis factor (TNF)-α in OBA-9, an immortalized human gingival epithelial cell. The luciferase activity of 3'-UTR of IL-6 mRNA was increased by TNF-α, Pg and PgLPS in OBA-9. Luciferase activity was also increased in HuR-over-expressing OBA-9 following a bacterial stimulation. Down-regulation of HuR by siRNA resulted in a decrease in mRNA expression and production of IL-6. In contrast, the over-expression of HuR increased IL-6 mRNA expression and production in OBA-9. The HuR inhibitor, quercetin, suppressed Pg-induced HuR mRNA expression and IL-6 production in OBA-9. An oral inoculation with quercetin also inhibited bone resorption in ligature-induced periodontitis model mice as a result of down-regulation of IL-6. These results show that HuR modulates inflammatory responses by regulating IL-6.

Reparative bone-like tissue formation in the tooth of a systemic sclerosis patient

AIM

To report a case of reparative bone-like tissue formation in the tooth of a patient with systemic sclerosis.

SUMMARY

A 58-year-old Japanese female patient with systemic sclerosis was referred because of tooth fracture. Cone beam computerized tomography (CBCT) revealed multiple root resorption and the unclear transition from alveolar bone to root profile. A sample from a fractured tooth was analysed histologically. Haematoxylin and eosin-stained sections revealed the irregular replacement of pulp and dentine by bone-like tissue. Calcinosis was noted in various parts of the body and a histological analysis identified it as dystrophic calcification on sclerosed fibrous connective tissue. Bite force and the occlusal area were markedly weaker than the means for female of the same age.

KEY LEARNING POINTS

CBCT may be more useful than dental radiography for diagnosing multiple root resorption in systemic sclerosis patients. When systemic sclerosis patients have calcinosis, their root status must be examined carefully. When root resorption is present in systemic sclerosis patients, reparative bone-like tissue formation in teeth needs to be taken into account prior to the initiation of dental treatment.

Porphyromonas gingivalis infection exacerbates the onset of rheumatoid arthritis in SKG mice

Epidemiological studies have linked periodontitis to rheumatoid arthritis (RA). Porphyromonas gingivalis (Pg) was reported recently to produce citrullinated protein (CP) and increase anti-cyclic CP antibody (ACPA), both of which have been identified as causative factors of RA. In the present study, we determined the effects of Pg infection on the exacerbation of RA in a mouse model. RA model mice (SKG mice) were established by an intraperitoneal (i.p.) injection of laminarin (LA). Mice were divided into six groups, Ctrl (PBS injection), LA (LA injection), Pg/LA (Pg + LA injection), Pg (Pg injection), Ec/LA (Escherichia coli and LA injection) and Ec (E. coli injection). In order to evaluate RA, joint swelling by the arthritis score, bone morphology by microcomputed tomography (microCT), haematoxylin and eosin staining, ACPA, matrix metalloproteinase-3 (MMP-3) and cytokine level in serum by enzyme-linked immunosorbent assay were determined. Osteoclast differentiation from bone marrow mononuclear cells (BMCs) was examined to clarify the underlying mechanisms of RA. The presence of Pg and CP in joint tissue was also investigated. The arthritis score was threefold higher in the Pg/LA group than in the LA group. Severe bone destruction was observed in joint tissue of the Pg/LA group. A microCT analysis of the Pg/LA group revealed a decrease in bone density. ACPA, MMP-3, interleukin (IL)-2, IL-6, CXCL1 and macrophage inflammatory protein (MIP)-1α levels from the Pg/LA group were the highest. The osteoclastogenesis of BMCs was enhanced in the Pg/LA group. Furthermore, large amounts of Pg components and CP were detected in the Pg/LA group. In conclusion, Pg infection has the potential to exacerbate RA.

Hypoglycemic and Antioxidant Activities of the Water Extract of Aquilaria crassna Leaves in Streptozotocin-Nicotinamide-Induced Type-2 Diabetic Mice

Antidiabetic effect of the water extract of Aquilaria crassna (A. crassna) leaves was recently claimed by some diabetic patients in Thailand, whereas its experimental evidence has not been published yet. The present study was therefore conducted to investigate pharmacological activities of the water extract of A. crassna leaves, focusing on its antioxidative and hypoglycemic effects in vitro and in vivo using streptozotocin (STZ)-nicotinamide (NA)-induced type 2 diabetic (DM) mice. An antioxidant activity of the herb extract was confirmed using a 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) radical scavenging assay, and its IC50 on DPPH inhibition was determined to be 34.6 μg/mL. The extract also inhibited α-glucosidase in a concentration-dependent manner with the IC50 of 36.3 μg/mL. An enzyme-kinetic analysis using a Lineweaver-Burk plot indicated that the inhibition of α-glucosidase by the herb extract is an uncompetitive type with the inhibition constant (K(i)) of 39.8 μg/mL. An intragastric pretreatment of 1,000 mg/kg A. crassna in STZ-NA-induced type-2 DM significantly lowered the blood glucose at 30 and 60 min after an oral loading of 2 g/kg glucose (p < 0.05 and p < 0.01, respectively), as compared with the untreated-diabetic control. After 4 weeks-daily administration of 500 and 1,000 mg/kg A. crassna extract, the blood glucose levels were significantly reduced by about 66% and 86%, respectively, as compared with the untreated-diabetic control (p < 0.01). However, the expression of GLUT4 in skeletal muscle, detected by ELISA, was not significantly changed with the herb extract. In conclusion, our findings are the first to clearly demonstrate the hypoglycemic effects of A. crassna and to propose the α-glucosidase inhibition as an antidiabetic mechanism of the herb activity.

Simultaneous optimization of limited sampling points for pharmacokinetic analysis of amrubicin and amrubicinol in cancer patients

AIM

Limited sampling points for both amrubicin (AMR) and its active metabolite amrubicinol (AMR-OH) were simultaneously optimized using Akaike's information criterion (AIC) calculated by pharmacokinetic modeling.

METHODS

In this pharmacokinetic study, 40 mg/m(2) of AMR was administered as a 5-min infusion on three consecutive days to 21 Japanese lung cancer patients. Blood samples were taken at 0, 0.08, 0.25, 0.5, 1, 2, 4, 8 and 24 h after drug infusion, and AMR and AMR-OH concentrations in plasma were quantitated using a high-performance liquid chromatography. The pharmacokinetic profile of AMR was characterized using a three-compartment model and that of AMR-OH using a one-compartment model following a first-order absorption process. These pharmacokinetic profiles were then integrated into one pharmacokinetic model for simultaneous fitting of AMR and AMR-OH. After fitting to the pharmacokinetic model, 65 combinations of four sampling points from the concentration profiles were evaluated for their AICs. Stepwise regression analysis was applied to select the sampling points for AMR and AMR-OH to predict the area under the concentration-time curves (AUCs) at best.

RESULTS

Of the three combinations that yielded favorable AIC values, 0.25, 2, 4 and 8 h yielded the best AUC prediction for both AMR (R(2) = 0.977) and AMR-OH (R(2) = 0.886). The prediction error for AUC was less than 15%.

CONCLUSION

The optimal limited sampling points of AMR and AMR-OH after AMR infusion were found to be 0.25, 2, 4 and 8 h, enabling less frequent blood sampling in further expanded pharmacokinetic studies for both AMR and AMR-OH.

Representation of older patients in clinical trials for drug approval in Japan

To examine how target patients seen in clinical practice are represented in clinical trials for approved drugs in Japan, we compared the age distribution of older patients enrolled in confirmatory clinical trials for regulatory approval with that of the estimated actual patient population. Drugs for 6 chronic conditions common among older patients (diabetes mellitus, hypertension, rheumatoid arthritis, non-small cell lung cancer, depression and Alzheimer's disease) launched by 2012 in Japan were selected. The disparity in age distribution between patients in trials and patients seen in clinical practice varied depending on the disease, but older patients, especially those aged 75 or older, were generally underrepresented in clinical trials for regulatory approval in Japan. Under-representation of older patients in hypertension trials was particularly marked compared to other conditions, despite the similarity in age distribution of patients seen in clinical practice. One factor causing this disparity may be an upper age limit in clinical trial protocols. More effort is needed to properly characterize the benefits and risks of drugs for older patients. This should include the active enrollment of older patients in clinical trials, the establishment of better assessment tools such as pharmacometric approaches, and the appropriate planning and conducting of post-marketing surveys and studies.

The use of 13C-erythromycin as an in vivo probe to evaluate CYP3A-mediated drug interactions in rats

(14)C-erythromycin breath test has been utilized to evaluate the extent of CYP3A activity in vivo. However, its radioactivity sometimes impedes its clinical application. In this study, we employed erythromycin labeled with (13)C ((13)C-EM), a nonradioactive stable isotope, as an in vivo probe of breath test to evaluate CYP3A-mediated drug interactions in rats. A physiologically based pharmacokinetic (PBPK) model to describe (13)CO(2) exhalation altered by drug interactions was newly constructed. Rats received an intravenous or oral administration of (13)C-EM with or without a CYP3A inhibitor or inducer, that is, ketoconazole (KCZ) or dexamethasone (DEX), respectively. Breath samples were taken at designated times, measured with an infrared spectrophotometer, and the Δ(13) CO(2) value (‰) in each sample was obtained. The C(max) and AUC(0-t) of Δ(13) CO(2) were significantly decreased with KCZ and increased with DEX. The PBPK model in this study successfully described the (13)CO(2) exhalation after (13)C-EM administration in the absence and presence of drug interactions. In conclusion, this study proposed a simple and rapid in vivo methodology to utilize (13)C-EM for the quantitative analysis of CYP3A inhibition and induction. This method using small animals may be useful in early drug development processes.

Comparison of physicians' compliance, clinical efficacy, and drug cost before and after introduction of Asthma Prevention and Management Guidelines in Japan (JGL2003)

BACKGROUND

This study investigated the variations in the clinical efficacy and drug cost following the introduction of the Asthma Prevention and Management Guidelines in Japan (JGL2003).

METHODS

The medical charts of fifty outpatients treated continuously for asthma, aged 16-50 years, from October 2002 to October 2004 at Showa University Hospital were analyzed for physicians' compliance with asthma guidelines, symptom severity, episodes in various occasions, prescriptions and drug costs.

RESULTS

Physicians' compliance with the guidelines, which were defined as the number of patient visits treated in conformity with the JGL over the total number of patient visits, was found to be high before (89.4%) and after (90.3%) the introduction of JGL2003, without a statistical difference. On the other hand, the distribution of asthma symptom severity varied significantly (P<0.0001). Fewer patients were recognized as having more severe asthma symptoms after the introduction of JGL2003. Significantly more patients with severe asthma symptoms were detected in the physicians' noncompliant group than in the compliant group (P<0.0001). The number of patients prescribed with oral corticosteroids, long-acting beta2-agonists containing patches, long-acting oral beta2-agonists, short-acting inhaled beta2-agonists, sustained-released theophylline and leukotriene receptor antagonists decreased after the introduction of JGL2003. Furthermore, the total annual drug cost per patient decreased significantly by an average of 16,259 yen (P=0.006).

CONCLUSIONS

The JGL2003 was judged to have improved criteria, which thus resulted in the high compliance of physicians with the guidelines, in the remission of asthma symptoms and in the reduction in the total annual drug cost per patient.

Desirable pharmacokinetic properties of (13)C-uracil as a breath test probe of gastric emptying in comparison with (13)C-acetate and (13)C-octanoate in rats

OBJECTIVE

To investigate the possible use of a (13)C-uracil breath test for gastric emptying by evaluating the pharmacokinetic properties of (13)C-uracil in a breath test in rats, in comparison with (13)C-acetate and (13)C-octanoate, traditional (13)C-probes for gastric emptying.

MATERIAL AND METHODS

Absorption of the (13)C-probes from different parts of the gastrointestinal tract was evaluated in fasted rats. (13)C-Uracil breath tests for gastric emptying were carried out in conditions where delayed gastric emptying was induced by clonidine, quinpirole, and propantheline, and in a postoperative ileus model. Following oral administration, we measured residual (13)C-uracil in the stomach and correlated the amount with the breath response.

RESULTS

All the (13)C-probes employed were well absorbed from the intestine after intraduodenal administration. After intragastric administration, (13)C-uracil was not absorbed from the stomach, but (13)C-acetate and (13)C-octanoate were partly absorbed from the stomach. The cumulative (14)C-uracil recovery (%) at 168 h was 92.3, 6.3, or 0.5%, from expired gases, urine, and feces, respectively. Delta(13)C values in (13)C-uracil breath tests were decreased in conditions characterized by delayed gastric emptying. A highly negative correlation was observed between the breath response and the residual ratio of (13)C-uracil in the stomach after oral administration of (13)C-uracil, indicating that (13)C-uracil can be used as an in vivo probe for evaluating gastric emptying in a quantitative manner.

CONCLUSIONS

This study showed that (13)C-uracil has desirable pharmacokinetic properties as an in vivo probe of gastric emptying. It is thus suggested that the (13)C-uracil breath test may be useful for the measurement of gastric emptying in humans.

[Dose estimation for renal-excretion drugs in neonates and infants based on physiological development of renal function]

We established dose estimation formulae for renal-excretion drugs using the glomerular filtration rate (GFR), tubular secretion clearance (Sc), and unbound fraction of drug in plasma (fp) as a renal function index of physiological development in neonates and infants not more than 2 years of age. A dose ratio of (DC/DA)=clearance ratio of (CLC/CLA) congruent with(fpC.GFRC)/(fpA.GFRA) for neonates and infants/adults was applied to drugs with fp.GFR>Sc, while DC/DA=CLC/CLA congruent with(beta.BSAC+fpC.GFRC)/(beta.BSAA+fpA.GFRA) was applied to drugs with Sc>fp.GFR using the coefficient of each drug (beta) and body surface area (BSA). Validity of the estimation formulae was investigated in drugs with fp.GFR>Sc such as vancomycin (VCM), arbekacin (ABK), fosfomycin (FOM) and norfloxacin (NFLX), and in drugs with Sc>fp.GFR such as digoxin (DGX) and amoxicillin (AMPC). First, we compared the clearance ratio (CLC/ CLA) of VCM, ABK, and DGX estimated by our method with those calculated using the Japanese population clearance values and those estimated allometrically (BSAC/BSAA). Next, we compared the established doses of all drugs investigated with the doses for neonates and infants calculated from the conventional dose estimation methods for children and our estimation formulae, and evaluated our method. As a result, favorable consistency was observed in the CL ratio for all drugs, and the doses of VCM, FOM, NFLX and AMPC calculated from our estimation formulae approximated the established doses. In conclusion, the validity of the dose estimation method using pharmacokinetic factors related to physiological development (i.e., GFR, fp, Sc) for renal-excretion drugs in neonates and infants was demonstrated.

Homozygous CDA*3 is a major cause of life-threatening toxicities in gemcitabine-treated Japanese cancer patients

Among 242 Japanese pancreatic cancer patients, three patients (1.2%) encountered life-threatening toxicities, including myelosuppression, after gemcitabine-based chemotherapies. Two of them carried homozygous CDA*3 (CDA208G>A [Ala70Thr]), and showed extremely low plasma cytidine deaminase activity and gemcitabine clearance. Our results suggest that homozygous *3 is a major factor causing gemcitabine-mediated severe adverse reactions among the Japanese population.

A new statistical screening approach for finding pharmacokinetics-related genes in genome-wide studies

Biomedical researchers usually test the null hypothesis that there is no difference of the population mean of pharmacokinetics (PK) parameters between genotypes by the Kruskal-Wallis test. Although a monotone increasing pattern with a number of alleles is expected for PK-related genes, the Kruskal-Wallis test does not consider a monotonic response pattern. For detecting such patterns in clinical and toxicological trials, a maximum contrast method has been proposed. We show how that method can be used with pharmacogenomics data to a develop test of association. Further, using simulation studies, we compare the power of the modified maximum contrast method to those of the maximum contrast method and the Kruskal-Wallis test. On the basis of the results of those studies, we suggest rules of thumb for which statistics to use in a given situation. An application of all three methods to an actual genome-wide pharmacogenomics study illustrates the practical relevance of our discussion.

Proposal for a new clinical entity, IgG4-positive multiorgan lymphoproliferative syndrome: analysis of 64 cases of IgG4-related disorders

BACKGROUND

Mikulicz's disease (MD) has been considered as one manifestation of Sjögren's syndrome (SS). Recently, it has also been considered as an IgG(4)-related disorder.

OBJECTIVE

To determine the differences between IgG(4)-related disorders including MD and SS.

METHODS

A study was undertaken to investigate patients with MD and IgG(4)-related disorders registered in Japan and to set up provisional criteria for the new clinical entity IgG(4)-positive multiorgan lymphoproliferative syndrome (IgG(4)+MOLPS). The preliminary diagnostic criteria include raised serum levels of IgG(4) (>135 mg/dl) and infiltration of IgG(4)(+) plasma cells in the tissue (IgG(4)+/IgG+ plasma cells >50%) with fibrosis or sclerosis. The clinical features, laboratory data and pathologies of 64 patients with IgG(4)+MOLPS and 31 patients with typical SS were compared.

RESULTS

The incidence of xerostomia, xerophthalmia and arthralgia, rheumatoid factor and antinuclear, antiSS-A/Ro and antiSS-B/La antibodies was significantly lower in patients with IgG(4)+MOLPS than in those with typical SS. Allergic rhinitis and autoimmune pancreatitis were significantly more frequent and total IgG, IgG(2), IgG(4) and IgE levels were significantly increased in IgG(4)+MOLPS. Histological specimens from patients with IgG(4)+MOLPS revealed marked IgG(4)+ plasma cell infiltration. Many patients with IgG(4)+MOLPS had lymphocytic follicle formation, but lymphoepithelial lesions were rare. Few IgG(4)+ cells were seen in the tissue of patients with typical SS. Thirty-eight patients with IgG(4)+MOLPS treated with glucocorticoids showed marked clinical improvement.

CONCLUSION

Despite similarities in the involved organs, there are considerable clinical and pathological differences between IgG(4)+MOLPS and SS. Based on the clinical features and good response to glucocorticoids, we propose a new clinical entity: IgG(4)+MOLPS.

Effect of hematocrit on pharmacokinetics of tacrolimus in adult living donor liver transplant recipients

OBJECTIVE

Plasma drug concentrations are generally considered to reflect efficacy and pharmacokinetics more directly than those in whole blood. However, whole blood has been selected as the matrix to monitor concentrations of tacrolimus (FK506), because it is difficult to accurately measure plasma FK506 concentrations. Because FK506 highly and saturably binds in blood cells, a change in hematocrit value (Hct) may affect FK506 pharmacokinetics. Therefore, we investigated effects of Hct on FK506 pharmacokinetics.

METHODS

First, we analyzed data on FK506 distribution among human blood cells in vitro. Briefly, we employed an equation, which describes saturable binding of FK506 to blood cells, and simulated plasma FK506 concentrations and clearances using the above equation with respect to a variable Hct. Subsequently, we retrospectively analyzed dosages and whole blood FK506 concentrations to predict plasma FK506 concentrations in living donor transplant recipients.

RESULTS

In the simulation study, the Hct changed plasma FK506 concentrations and clearances based in whole blood. In living donor liver transplant recipients, whole blood FK506 concentrations were maintained within a therapeutic range, while the Hct varied after transplantation. The correlation of Hct with the ratio of dose/trough concentrations of FK506 (D/C) in plasma (D/Cp) (R = -0.23, n = 343) was weaker than that for D/C in whole blood (D/CWB) (R = -0.53, n = 343).

CONCLUSION

Hct may be an important factor affecting the pharmacokinetics of FK506 in living donor liver transplantation recipients. It may be necessary to take Hct into consideration in the FK506 dosing regimen, especially when the Hct is low.

Cooperative induction of 15-lipoxygenase in rheumatoid synovial cells by IL-4 and proinflammatory cytokines

OBJECTIVE

To clarify the role of interleukin-4 (IL-4) in the expression of 15-lipoxygenase (15-LOX), whose metabolities are known to suppress the inflammatory reaction, in freshly prepared rheumatoid synovial cells.

METHODS

Adherent synovial cells were prepared by enzymatic digestion of synovia obtained from patients with rheumatoid arthritis (RA). Protein expression of 15-LOX was determined by Western blot analysis. The messenger RNAs of 15-LOX were determined by reverse transcription and the polymerase chain reaction (RT-PCR).

RESULTS

Freshly prepared rheumatoid synovial cells did not express 15-LOX at either the mRNA or protein levels. IL-4 induced the protein expression of 15-LOX after 24 hours of culture. Although interleukin-1 alpha (IL-1 alpha) and tumor necrosis factor alpha (TNF alpha), major inflammatory cytokines in rheumatoid synovia, did not induce the expression of 15-LOX, IL-4 and these inflammatory cytokines synergistically enhanced the protein expression of 15-LOX. The synergistic effect was also observed at the level of mRNA.

CONCLUSIONS

We demonstrate that IL-4 cooperated with the inflammatory cytokines IL-1 alpha and TNF alpha to enhance the expression of 15-LOX in rheumatoid synovial cells. Since 15-LOX metabolites have potent anti-inflammatory actions, our data suggest that IL-4 might downregulate rheumatoid inflammation via the induction of 15-LOX and its metabolites.