Decoding cellular deformation from pseudo-simultaneously observed Rho GTPase activities.

Limitations in simultaneously observing the activity of multiple molecules in live cells prevent researchers from elucidating how these molecules coordinate the dynamic regulation of cellular functions. Here, we propose the motion-triggered average (MTA) algorithm to characterize pseudo-simultaneous dynamic changes in arbitrary cellular deformation and molecular activities. Using MTA, we successfully extract a pseudo-simultaneous time series from individually observed activities of three Rho GTPases: Cdc42, Rac1, and RhoA. To verify that this time series encoded information on cell-edge movement, we use a mathematical regression model to predict the edge velocity from the activities of the three molecules. The model accurately predicts the unknown edge velocity, providing numerical evidence that these Rho GTPases regulate edge movement. Data preprocessing using MTA combined with mathematical regression provides an effective strategy for reusing numerous individual observations of molecular activities.

[Determination of Flufenacet and Its Metabolites in Agricultural Products by LC-MS/MS].

A simultaneous analytical method based on LC-MS/MS was developed for the determination of flufenacet and its metabolites, [(4-fluorophenyl)(1-methylethyl) amino]oxo-acetic acid and [N-(4-fluorophenyl)-N-(1-methylethyl) acetamide]-2-sulfinylacetic acid, in agricultural products. The compounds were extracted from samples with methanol. The crude extracts were purified using Bond Elut C18 and InertSep GC/PSA, then determined by LC-MS/MS. The average recoveries (n=5) from 4 kinds of agricultural products (wheat, soybean, potato and tomato) spiked at the level of the MRLs or the uniform limits (0.01 µg/g) were 70.6-97.0%, and the relative standard deviations were less than 5%. The lower limits of quantitation of flufenacet and its metabolites were 0.01 µg/g.

Prodromal signs and symptoms of serious infections with tocilizumab treatment for rheumatoid arthritis: Text mining of the Japanese postmarketing adverse event-reporting database.

OBJECTIVE: To search for signs and symptoms before serious infection (SI) occurs in tocilizumab (TCZ)-treated rheumatoid arthritis (RA) patients. METHODS: Individual case safety reports, including structured (age, sex, adverse event [AE]) and unstructured (clinical narratives) data, were analyzed by automated text mining from a Japanese post-marketing AE-reporting database (16 April 2008-10 April 2015) assuming the following: treated in Japan; TCZ RA treatment; ≥1 SI; unable to exclude causality between TCZ and SIs. RESULTS: The database included 7653 RA patients; 1221 reports met four criteria, encompassing 1591 SIs. Frequent SIs were pneumonia (15.9%), cellulitis (9.9%), and sepsis (5.0%). Reports for 782 patients included SI onset date; 60.7% of patients had signs/symptoms ≤28 days before SI diagnosis, 32.7% had signs/symptoms with date unidentified, 1.7% were asymptomatic, and 4.9% had unknown signs/symptoms. The most frequent signs/symptoms were for skin (swelling and pain) and respiratory (cough and pyrexia) infections. Among 68 patients who had normal laboratory results for C-reactive protein, body temperature, and white blood cell count, 94.1% had signs or symptoms of infection. CONCLUSION: This study identified prodromal signs and symptoms of SIs in RA patients receiving TCZ. Data mining clinical narratives from post-marketing AE databases may be beneficial in characterizing SIs.

Effectiveness and safety of tocilizumab in achieving clinical and functional remission, and sustaining efficacy in biologics-naive patients with rheumatoid arthritis: The FIRST Bio study.

OBJECTIVE: To evaluate effectiveness and safety of tocilizumab (TCZ) in biologic-naive Japanese patients with rheumatoid arthritis (RA) in real-world settings, and to analyze the relationship between disease duration and clinical outcomes. METHODS: The FIRST Bio study was a postmarketing surveillance study of intravenous TCZ in biologics-naive patients who had a prior inadequate response or were intolerant to ≥1 conventional synthetic disease-modifying antirheumatic drug (csDMARD). Effectiveness, safety, and concomitant csDMARD administration were assessed. RESULTS: Of the 839 patients analyzed, 72.3% completed 52 weeks of treatment. The Clinical Disease Activity Index (CDAI) remission rate at week 52 was 36.8%. Contributing factors for CDAI remission were younger age, early disease stage, and no comorbidities. Health Assessment Questionnaire Disability Index ≤0.5 was achieved in 65.1% of patients, and was significantly associated with disease duration. Discontinuation of concomitant methotrexate (MTX) and glucocorticoids (GCs) was possible in 19.3% and 34.1% of patients, respectively, without decreasing remission rate. The incidence (events/100 patient-years) of serious adverse events was 18.09, the most common being infection. CONCLUSION: These data validate the importance of TCZ treatment in the early stages of RA in biologic-naive patients to achieve increased effectiveness. The safety profile of TCZ was reconfirmed. Furthermore, TCZ therapy may allow discontinuation of concomitant MTX and GCs without affecting remission.

Drug free REmission/low disease activity after cessation of tocilizumab (Actemra) Monotherapy (DREAM) study.

OBJECTIVES: To investigate the duration of remission and low disease activity (LDA) after cessation of tocilizumab (TCZ) treatment in rheumatoid arthritis patients who showed remission or LDA as assessed by DAS28 in response to preceding TCZ monotherapy, and to explore the factors contributing to prolonged efficacy duration. METHODS: Disease activity was monitored for 56 weeks. The rate of continued efficacy was estimated by Kaplan-Meier curves. RESULTS: A total of 187 patients were eligible. At baseline of this study, median disease duration was 7.8 years, preceding TCZ treatment period was 4.0 years and DAS28 was 1.5. The rate of continued LDA at 52 weeks was 13.4 % according to the Kaplan-Meier estimate. 19 patients (10 %) were completely drug-free and 17 patients (9.1 %) fulfilled DAS28 remission at 52 weeks. Multivariate Cox regression analysis identified low serum IL-6 and normalisation of MMP-3 levels at cessation of TCZ as independent predictive markers for longer duration of LDA. In patients with low serum IL-6 (<12.9 pg/mL) and normal MMP-3 levels, the rate of continued LDA reached 38.0 % at 52 weeks. CONCLUSIONS: TCZ monotherapy may induce biologics-free remission or LDA without concomitant use of synthetic DMARDs. Serum levels of IL-6 and MMP-3 are useful markers for identifying patients who could discontinue TCZ without acute disease flare.

Retreatment efficacy and safety of tocilizumab in patients with rheumatoid arthritis in recurrence (RESTORE) study.

OBJECTIVES: To evaluate the safety and efficacy of retreatment with tocilizumab (TCZ) in patients who had participated in the DREAM study (Drug free remission/low disease activity after cessation of tocilizumab [Actemar] monotherapy study) and had experienced loss of efficacy. METHODS: Patients were retreated with TCZ or other disease modifying antirheumatic drugs (DMARDs). Disease activity was measured using the 28-joint disease activity score (DAS28) for 12 weeks. RESULTS: A total of 164 eligible patients, including 161 who experienced loss of efficacy within 52 weeks of the DREAM study, resumed treatment: 157 with TCZ and 7 with DMARDs and/or infliximab. Of TCZ-treated patients, 88.5 % (139 patients) achieved DAS28 <2.6 within 12 weeks, whereas among patients treated with DMARDs and/or infliximab only 14.3 % (1 patient) achieved DAS28 <2.6. Adverse events were observed in 70 TCZ-treated patients (44.0 %), but no serious infusion reactions were observed. CONCLUSIONS: Retreatment with TCZ was well-tolerated and effective in patients who had responded to the preceding TCZ monotherapy but had experienced loss of efficacy after cessation of TCZ.

Chemical propulsion using ionic liquids.

Chemical propulsion generates motion by directly converting locally stored chemical energy into mechanical energy. Here, we describe chemically driven autonomous motion generated by using imidazolium-based ionic liquids on a water surface. From measurements of the driving force of a locomotor loaded with an ionic liquid and observations of convection on the water surface originating from the ionic liquid container of the locomotor, the driving mechanism of the motion is found to be due to the Marangoni effect that arises from the anisotropic distribution of ionic liquids on the water surface. The maximum driving force and the force-generation duration are determined by the surface activity of the ionic liquid and the solubility of the ionic liquid in water, respectively. Because of the special properties of ionic liquids, a chemical locomotor driven by ionic liquids is promising for realizing autonomous micromachines and nanomachines that are safe and environmentally friendly.

Assessment of the validity of the 28-joint disease activity score using erythrocyte sedimentation rate (DAS28-ESR) as a disease activity index of rheumatoid arthritis in the efficacy evaluation of 24-week treatment with tocilizumab: subanalysis of the SATORI study.

As tocilizumab (TCZ) greatly inhibits inflammatory markers, methods of evaluating rheumatoid arthritis (RA) disease activity that include inflammatory markers may overestimate the effect of TCZ treatment. We have evaluated the impact of inflammatory markers on the efficacy of TCZ by comparing the efficacy indicated by the 28-joint disease activity score using erythrocyte sedimentation rate (DAS28-ESR) with that indicated by the clinical and simplified disease activity indexes (CDAI and SDAI, respectively) and the American College of Rheumatology (ACR) core set criteria in a double-blind study of TCZ-the SATORI study. The Spearman correlation coefficient between DAS28-ESR and CDAI was comparable between that at week 24 and that at baseline [correlation coefficient at baseline and week 24 was 0.823 (p < 0.0001) and 0.818 (p < 0.0001), respectively]. A large difference between the DAS28 remission rate and CDAI remission rate was observed at week 24. However, these results are comparable to those of a previous study conducted with non-TCZ-treated patients. Moreover, the same results were obtained in the comparison between the DAS28-ESR and SDAI, even though the SDAI includes an inflammatory parameter as a component. These results confirm that the DAS28-ESR has a validity comparable to that of other methods in terms of evaluating the RA treatment efficacy of TCZ, despite its strong inflammatory marker-inhibiting effects.

Safety and efficacy profiles of tocilizumab monotherapy in Japanese patients with rheumatoid arthritis: meta-analysis of six initial trials and five long-term extensions.

We present safety and efficacy data from Japanese clinical studies on monotherapy with tocilizumab (TCZ), a humanized anti-interleukin 6 receptor monoclonal antibody, in which 601 patients with moderate to severe rheumatoid arthritis, with a total of 2188 patient-years (pt-yr) exposure, were enrolled. The median treatment duration was 3.8 years. The incidence of adverse events (AEs), including abnormal laboratory test results, was calculated as 465.1 per 100 pt-yr. The most common serious adverse events (SAEs) were infections (6.22 per 100 pt-yr). There was no increase in the frequency of AEs or SAEs with long-term treatment. Abnormalities in the laboratory test results, such as increases in lipid parameters or abnormal liver function parameters, were common, but most were mild and there were no SAEs related to them. At baseline, 546 patients (90.8%) were taking corticosteroids; of these, 77.8% were able to decrease their corticosteroid dose during the study period, while 35.2% discontinued corticosteroids altogether. In the patients treated longer than 5 years, 91.3, 73.0, and 51.3% met the ACR20, ACR50, and ACR70 response criteria, respectively, and 59.7% met the DAS remission criterion (DAS28 <2.6) at 5 years. In conclusion, based on these results, TCZ has shown good tolerability and high efficacy during long-term treatment.

Mechanisms and pathologic significances in increase in serum interleukin-6 (IL-6) and soluble IL-6 receptor after administration of an anti-IL-6 receptor antibody, tocilizumab, in patients with rheumatoid arthritis and Castleman disease.

Interleukin-6 (IL-6) plays pathologic roles in immune-inflammatory diseases such as rheumatoid arthritis (RA) and Castleman disease. By inhibiting IL-6 receptors (IL-6Rs), tocilizumab (a humanized anti-IL-6R antibody) ameliorates the symptoms of these diseases and normalizes acute-phase proteins, including C-reactive protein (CRP). We found that tocilizumab treatment increased serum levels of IL-6 and soluble IL-6R (sIL-6R). To investigate the pathologic significance of these increases, we analyzed the kinetics of serum IL-6 and sIL-6R and the proportion of sIL-6R saturated with tocilizumab after tocilizumab administration in patients with RA and Castleman disease and then compared the results with the CRP values. Serum IL-6 and sIL-6R markedly increased after tocilizumab administration in both RA and Castleman disease. As long as free tocilizumab was detectable, sIL-6R was saturated with tocilizumab and IL-6 signaling was completely inhibited. We concluded that it is likely that sIL-6R increased because its elimination half-life was prolonged by the formation of tocilizumab/sIL-6R immune complex, and that free serum IL-6 increased because IL-6R-mediated consumption of IL-6 was inhibited by the unavailability of tocilizumab-free IL-6R. We also concluded that the increased level of free IL-6 during tocilizumab treatment closely reflects the actual endogenous IL-6 production and true disease activity.

Toxicity, pharmacokinetics, and dose-finding study of repetitive treatment with the humanized anti-interleukin 6 receptor antibody MRA in rheumatoid arthritis. Phase I/II clinical study.

OBJECTIVE: To evaluate the safety and pharmacokinetics of multiple infusions of a humanized anti-interleukin-6 (IL-6) receptor antibody, MRA, in patients with rheumatoid arthritis (RA). METHODS: In an open label trial, 15 patients with active RA were intravenously administered 3 doses (2, 4, or 8 mg/kg) of MRA biweekly for 6 weeks, and pharmacokinetics were assessed. Patients continued on MRA treatment for 24 weeks, and were then assessed for safety and efficacy. RESULTS: The treatment was well tolerated at all doses with no severe adverse event. Increased total serum cholesterol was detected as an MRA related reaction in 10/15 (66%) patients. There was no statistically significant difference in the frequency of adverse events among the 3 dose groups. There were no new observations of antinuclear antibody or anti-DNA antibody, and no anti-MRA antibody was detected. The T1/2 increased with repeated doses and as the dose increased. T1/2 after the 3rd dose of 8 mg/kg reached 241.8 +/- 71.4 h. In 12/15 (80%) patients whose serum MRA was detectable during the treatment period, objective inflammatory indicators such as C-reactive protein, erythrocyte sedimentation rate, and serum amyloid A were completely normalized at 6 weeks, although there was no statistically significant difference in efficacy among the 3 dose groups. Nine of 15 patients achieved ACR 20 at 6 weeks. At 24 weeks, 13 patients achieved ACR 20 and 5 achieved ACR 50. CONCLUSION: Repetitive treatment with MRA was safe and normalized acute phase response in patients with RA. Optimal dosing schedule was not defined in this small study, but maintenance of serum MRA concentration seemed important to achieve efficacy.

Polyglutamation of a novel antifolate, MX-68, is not necessary for its anti-arthritic effect.

N-[[4-[(2,4-diaminopteridin-6-yl)methyl]-3,4-dihydro-2H-1,4-benzothiazin-7-yl]-carbonyl]-L-homoglutamic acid (MX-68), a derivative of methotrexate, was chemically designed to resist polyglutamation and to have a high affinity for dihydrofolate reductase, in an attempt to reduce the side effects of methotrexate. We confirmed that MX-68 did not undergo polyglutamation and investigated the pharmacological activities of MX-68 compared with methotrexate. (1) In vitro: MX-68 inhibited the activity of dihydrofolate reductase to the same degree as methotrexate-tetraglutamate. MX-68 treatment produced a similar anti-proliferative effect to that of methotrexate. However, the intracellular concentration of MX-68 was much lower than the sum of the levels of methotrexate and its polyglutamate, and the effects of MX-68 disappeared when it was removed from the culture medium. (2) In vivo: Oral administration of MX-68 suppressed the development of collagen-induced arthritis in mice and adjuvant-induced arthritis in rats, in a similar fashion to that of methotrexate. These results indicate that polyglutamation is not essential for the anti-arthritic effect of antifolates.