Uterine sarcoma with posterior reversible encephalopathy syndrome associated with pazopanib.

WHAT IS KNOWN AND OBJECTIVE: Our objective is to report on a case of posterior reversible encephalopathy syndrome associated with pazopanib. CASE DESCRIPTION: A 64-year-old patient with uterine sarcoma developed PRES 3 days after pazopanib was initiated. After the discontinuation of pazopanib, the symptoms of PRES improved. WHAT IS NEW AND CONCLUSION: The first report worldwide to describe a patient with uterine sarcoma experiencing PRES caused by pazopanib. Patients with uterine sarcoma may experience PRES, even in the early phase of pazopanib therapy.

Hypertension and Proteinuria as Predictive Factors of Effects of Bevacizumab on Advanced Breast Cancer in Japan.

Bevacizumab (BV), an inhibitor of vascular endothelial growth factor, is used in combination with paclitaxel (PTX) to treat advanced breast cancer. Hypertension and proteinuria are characteristic adverse events of BV therapy. We assessed the potential of these adverse events as predictors of BV treatment responses. Our results revealed that groups that developed hypertension and proteinuria early (by day 56) had a stronger antitumor response (Fisher's exact test p<0.05). However, no significant difference was observed in progression-free survival (the Kaplan-Meier method and Log-rank test). As a reference, age, the treatment line, subtypes, liver and renal function, diabetes mellitus and hyperlipidemia history, body mass index, influencing concomitant medicine, average relative dose intensity and hematotoxicity did not significantly differ between groups with or without hypertension and with or without proteinuria. These results indicate the potential of the development of hypertension and proteinuria as predictors of improved outcomes with PTX plus BV therapy in patients with breast cancer. However, since both adverse events may preclude the continuation of treatment, their earlier management may be required.

Prediction Model of Serum Lithium Concentrations.

INTRODUCTION: Therapeutic drug monitoring is necessary for lithium, but clinical application of several prediction strategies is still limited because of insufficient predictive accuracy. We herein proposed a suitable model, using creatinine clearance (CLcr)-based lithium clearance (Li-CL). METHODS: Patients receiving lithium provided the following information: serum lithium and creatinine concentrations, time of blood draw, dosing regimen, concomitant medications, and demographics. Li-CL was calculated as a daily dose per trough concentration for each subject, and the mean of Li-CL/CLcr was used to estimate Li-CL for another 30 subjects. Serum lithium concentrations at the time of sampling were estimated by 1-compartment model with Li-CL, fixed distribution volume (0.79 L/kg), and absorption rate (1.5/hour) in the 30 subjects. RESULTS: One hundred thirty-one samples from 82 subjects (44 men; mean±standard deviation age: 51.4±16.0 years; body weight: 64.6±13.8 kg; serum creatinine: 0.78±0.20 mg/dL; dose of lithium: 680.2±289.1 mg/day) were used to develop the pharmacokinetic model. The mean±standard deviation (95% confidence interval) of absolute error was 0.13±0.09 (0.10-0.16) mEq/L. DISCUSSION: Serum concentrations of lithium can be predicted from oral dosage with high precision, using our prediction model.

Characterization of a recombinant Bacteroides fragilis sialidase expressed in Escherichia coli.

The human gut commensal Bacteroides fragilis produces sialidases that remove a terminal sialic acid from host-derived polysaccharides. Sialidase is considered to be involved in B. fragilis infection pathology. A native B. fragilis sialidase has been purified and characterized, and was shown to be post-translationally modified by glycosylation. However, the biochemical properties of recombinant B. fragilis sialidase expressed in a heterologous host remain uncharacterized. In this study, we examined the enzymatic properties of the 60-kDa sialidase NanH1 of B. fragilis YCH46, which was prepared as a recombinant protein (rNanH1) in Escherichia coli. In E. coli rNanH1 was expressed as inclusion bodies, which were separated from soluble proteins to allow solubilization of insoluble rNanH1 in a buffer containing 8 M urea and renaturation in refolding buffer containing 100 mM CaCl2 and 50 mM L-arginine. The specific activity of renatured rNanH1 measured using 4-methylumberiferyl-α-D-N-acetyl neuraminic acid as a substrate was 6.16 µmol/min/mg. The optimal pH of rNanH1 ranged from 5.0 to 5.5. The specific activity of rNanH1 was enhanced in the presence of calcium ions. rNanH1 preferentially hydrolyzed the sialyl α2,8 linkage and cleaved sialic acids from mucin and serum proteins (e.g., fetuin and transferrin) but not from α1-acid glycoprotein, which is similar to the previously observed biochemical properties for a native sialidase purified from B. fragilis SBT3182. The results and methods described in this study will be useful for preparing and characterizing recombinant proteins for other B. fragilis sialidase isoenzymes.

Effect of endurance for adverse drug reactions on the preference for aggressive treatments in cancer patients.

PURPOSE: Cancer patients receiving chemotherapy will sometimes conceal their discomfort, but an excessive endurance for adverse drug reactions (ADRs) can lead to a poorer prognosis. The aim of this study was to clarify the association between ADR endurance and a preference of cancer patients for aggressive treatments. METHODS: A cross-sectional study was undertaken of inpatients under 75 years of age receiving injectable systemic chemotherapy or oral chronic medications at hospitals in Japan. Subjects were asked to respond to a validated questionnaire to assess the extent of their ADR endurance and whether they would choose a novel, more aggressive therapy if their life expectancy was estimated at 2 years. RESULTS: Study participants were separated into the chemotherapy group (n = 36) and the non-chemotherapy group (n = 78). In the chemotherapy group, patients who had moderate ADR endurance scores were more likely to choose the new therapy (0-33, 34-67, and 68-100 points: 0.0, 54.5, and 27.3 %; χ (2) test, p = 0.15). Additionally, every patient on long-term chemotherapy (≥3 years) had high ADR endurance scores but did not choose the new, riskier treatment. In the non-chemotherapy group, the proportion of those choosing the new therapy was linearly associated with higher ADR endurance scores (25.9, 38.2, and 64.7 %; p = 0.04). CONCLUSION: Cancer patients may prefer aggressive therapies, even when self-estimations of ADR endurance are not very high, especially if they have been receiving chemotherapy for a short period of time. These patients should be observed with great caution.

Developing population pharmacokinetic parameters for high-dose methotrexate therapy: implication of correlations among developed parameters for individual parameter estimation using the Bayesian least-squares method.

Bayesian estimation enables the individual pharmacokinetic parameters of the medication administrated to be estimated using only a few blood concentrations. Due to wide inter-individual variability in the pharmacokinetics of methotrexate (MTX), the concentration of MTX needs to be frequently determined during high-dose MTX therapy in order to prevent toxic adverse events. To apply the benefits of Bayesian estimation to cases treated with this therapy, we attempted to develop an estimation method using the Bayesian least-squares method, which is commonly used for therapeutic monitoring in a clinical setting. Because this method hypothesizes independency among population pharmacokinetic parameters, we focused on correlations among population pharmacokinetic parameters used to estimate individual parameters. A two-compartment model adequately described the observed concentration of MTX. The individual pharmacokinetic parameters of MTX were estimated in 57 cases using the maximum likelihood method. Among the available parameters accounting for a 2-compartment model, V1, k10, k12, and k21 were found to be the combination showing the weakest correlations, which indicated that this combination was best suited to the Bayesian least-squares method. Using this combination of population pharmacokinetic parameters, Bayesian estimation provided an accurate estimation of individual parameters. In addition, we demonstrated that the degree of correlation among population pharmacokinetic parameters used in the estimation affected the precision of the estimates. This result highlights the necessity of assessing correlations among the population pharmacokinetic parameters used in the Bayesian least-squares method.

Factors responsible for long-term survival in metastatic breast cancer.

BACKGROUND: Although survival of patients with metastatic breast cancer (MBC) has been significantly prolonged over the past decade due to improvement of anti-cancer therapeutics, only a few patients survive for more than 10 years. It has not been determined which patients can have long-term survival with treatment. METHODS: To determine prognostic factors responsible for long-term survival, we retrospectively compared clinicopathologic factors of patients with MBC who survived for 50 months or more after diagnosis with patients who did not. Of 70 patients with MBC who received chemotherapy between November 2005 and September 2011, 23 patients who survived for 50 months or more after diagnosis and 28 patients who died within 50 months after diagnosis were assessed for their clinicopathologic factors and outcomes. RESULTS: The proportion of patients with hormone receptor-positive (HR+) tumors was significantly higher and the proportion of patients with triple negative tumors (TN) was lower in long-term survivors than in non-long-term survivors (HR+: 87% versus 28.6%, P=0.000037; TN: 13.1% versus 53.6%, P=0.0028). Metastatic site, number of disease sites, prior chemotherapeutic regimens and human epidermal growth factor receptor-2 (HER2) status did not differ between the two groups. The proportion of patients who received metronomic regimens was significantly higher in long-term survivors than in non-long-term survivors (65.2% versus 35.7%, P=0.034) when the most effective regimen among regimens that were received in metastatic settings was compared between the two groups. Overall response rate was significantly higher (82.6% versus 17.9%, P<0.00001) and time to treatment failure after receiving the most effective regimen was longer in long-term survivors than in non-long-term survivors (26 versus 5 months, P=0.0001). The number of chemotherapeutic regimens for breast cancer and that for MBC did not differ between the two groups. CONCLUSIONS: Patients with luminal-type MBC who benefit at least once from chemotherapy including metronomic regimens, or patients who continued to receive the most effective regimen for more than two years can be expected to have long-term survival after diagnosis of MBC, regardless of the number of chemotherapeutic regimens they had received.

Effects of angiotensin II AT1-receptor blockade on high fat diet-induced vascular oxidative stress and endothelial dysfunction in Dahl salt-sensitive rats.

We examined the effects of angiotensin II AT1-receptor blockade with olmesartan on high fat (HF) diet-induced vascular oxidative stress and endothelial dysfunction in normal salt (NS) diet-fed Dahl salt-sensitive (DSS) rats. Treatment with NS + HF diet (32% crude fat, 0.3% NaCl) for 20 weeks significantly increased blood pressure in DSS rats. NS + HF diet-fed DSS rats also showed higher plasma levels of thiobarbituric acid-reactive substances, aortic superoxide production, and mRNA levels of p22(phox) and gp91(phox) in aortic tissues than NS diet-fed DSS rats. Furthermore, acetylcholine-induced vasorelaxation of aorta from NS + HF diet-fed DSS rats was significantly reduced. In NS + HF diet-fed DSS rats, treatment with olmesartan medoxomil (10 mg/kg per day, p.o.) and hydralazine (25 mg/kg per day, p.o.) similarly decreased blood pressure. However, in these animals, only olmesartan normalized plasma levels of thiobarbituric acid-reactive substances, vascular superoxide in aortic tissues, and acetylcholine-induced vasorelaxation. These data indicate that HF diet-induced hypertension is associated with vascular oxidative stress and endothelial dysfunction in NS diet-treated DSS rats. Inhibition of angiotensin II AT1 receptors may elicit beneficial effects on HF-induced hypertension and vascular injury in subjects that have genetically enhanced sodium-sensitive blood pressure.

Limited sampling strategy for the estimation of mycophenolic acid area under the concentration-time curve treated in Japanese living-related renal transplant recipients with concomitant extended-release tacrolimus.

Mycophenolate mofetil (MMF) is used for oral administration to prevent rejection in renal transplant recipients, and is rapidly converted into mycophenolic acid (MPA), the active metabolite, by hydrolysis in vivo. The area under the concentration-time curve (AUC(0-12 h)) of MPA is considered to be an effective pharmacokinetics parameter for predicting acute rejection. However, frequent blood sampling is required to calculate AUC(0-12 h), which imposes a burden on patients and providers. Therefore, we examined a limited sampling strategy (LSS) for estimation of MPA-AUC(0-12 h) using only a trough level (C0) and two points including C0 in Japanese living-related renal transplant recipients with concomitant extended-release tacrolimus (ER-TAC). The present study suggests that better estimation of MPA-AUC(0-12 h) can be obtained by using two points including C0 as compared with only C0 regardless of transplant progress. Furthermore, blood collection points showing the highest estimation of MPA-AUC(0-12 h) by adding to C0 were C4 at pre-transplantation (Tx) and 1 month post-Tx, and C6 at 3 months post-Tx. We conjecture that changes in renal function and serum albumin (Alb) accompanying transplant progress are aggravating factors in terms of estimation, because there was also a significant difference in the reciprocal of serum creatinine (1/Scr) and Alb between pre-Tx and post-Tx in this study. In conclusion, the present study provides useful information for effective and efficient monitoring of MPA levels in Japanese living-related renal transplant recipients.

[Development of a One-minute Educational Video for Eye-drop Instillation and Changes in Instillation Behavior after Watching the Video].

We created a one-minute video titled "a simple method of eye-drop instillation" (video) for online instillation guidance, to compare the instillation method before and after study participants watch the video and verify the usefulness of watching the video. Moreover, we prepared a document questionnaire to investigate instillation habits and clarify instillation behavior. Study participants were randomly recruited from among students and faculty members via a poster posted at Tokushima Bunri University. The instillation behavior of the study participants was videotaped before and after they watched the video created by the authors. The images were played in a super slow motion, to confirm success or failure in instillation, drop sites, and eye-opening method. Of the 109 participants in the study, the successful instillation rate before and after watching the video was 55.0% and 69.7%, respectively. The use rate of wet wipes for finger disinfection before instillation increased from 0.0% before watching the video to 74.3% after watching the video. After watching the video, the blinking rate after instillation decreased from 95.4 to 45.0%, the rate of pressing the nasolacrimal duct increased from 2.8 to 77.1%, and the rate of wiping the drug solution spilled around the eyes increased from 89.9 to 98.2%. According to the questionnaire, 72.5% of the participants instilled one drop, 22.0% instilled two drops, and 5.5% instilled three drops or more. Watching the video significantly increased the successful instillation rate and improved instillation behavior. Thus, the video created by the authors can be used for online instillation guidance.

Erythroid recovery affects tacrolimus levels after engraftment during stem cell transplantation.

Tacrolimus is commonly used in stem-cell transplants (SCT) for prophylaxis of graft-versus-host disease and is continuously administered throughout transplantation. The dose of tacrolimus is frequently decreased to maintain a desired concentration during the recovery of hemocytes after engraftment. If parameters which affect tacrolimus clearance are identified, it is of clinical use to estimate concentrations and aid dosing. The objective of this study was to identify which hematologic parameters affect tacrolimus clearance. Seventeen consecutive Japanese patients with hematological malignancies who received allogeneic SCT between March 2004 and January 2007 were enrolled in this study. Their steady-state concentrations were routinely measured and standardized as the concentration/dose (C/D) ratio ((ng/mL)/(mg/kg/d)). Multivariate analysis was performed to identify which hemocyte parameters affected the C/D ratio. Of the 13 patients, gradual dose reduction was required to combat elevated tacrolimus concentrations. The mean post-engraftment C/D ratio was higher than the pre-engraftment C/D ratio in each patient. The mean C/D ratio for all patients after engraftment was 1.56-fold higher (p=0.00004, range: 1.04-3.03) than that before engraftment. The variation ratio was calculated by dividing the C/D ratio by that on the engraftment day. Multivariate analysis revealed that the reticulocyte (RET) level (×10(3) count/µL) was the sole parameter influencing this ratio, and both parameters were expressed as: Variation ratio=0.004×RET+1.0. RET recovery of patients could influence the C/D ratio and tacrolimus clearance was affected by recipient original red blood cells, but not that of transfused red blood cells.

[A Pharmacist's Query Avoiding Exacerbation of Adverse Effects in a Patient with Acyclovir Encephalopathy: A Case Report].

We report a haemodialysis patient with end-stage renal failure whom a pharmacist aided in the management of acyclovir (ACV) encephalopathy, which may have been related to valacyclovir hydrochloride (VACV) administered without sufficient dose reduction. The patient 78 years was admitted with a tentative diagnosis of varicella zoster viral meningitis. A pharmacist suspected ACV encephalopathy related to excessive VACV administration and raised a query with the attending physician. According to the pharmacist's proposal, ACV administration was discontinued and continuous hemodiafiltration (CHDF) was performed. On day 5 of hospitalisation, the consciousness disorder was improved. In this report, we showed the detailed CHDF conditions of the present case, and the contribution of a pharmacist to treating and avoiding ACV encephalopathy was discussed.

Enzymological analysis of the tumor suppressor A-C1 reveals a novel group of phospholipid-metabolizing enzymes.

A-C1 protein is the product of a tumor suppressor gene negatively regulating the oncogene Ras and belongs to the HRASLS (HRAS-like suppressor) subfamily. We recently found that four members of this subfamily expressed in human tissues function as phospholipid-metabolizing enzymes. Here we examined a possible enzyme activity of A-C1. The homogenates of COS-7 cells overexpressing recombinant A-C1s from human, mouse, and rat showed a phospholipase A½ (PLA½) activity toward phosphatidylcholine (PC). This finding was confirmed with the purified A-C1. The activity was Ca²âº independent, and dithiothreitol and Nonidet P-40 were indispensable for full activity. Phosphatidylethanolamine (PE) was also a substrate and the phospholipase A1 (PLA1) activity was dominant over the PLA2 activity. Furthermore, the protein exhibited acyltransferase activities transferring an acyl group of PCs to the amino group of PEs and the hydroxyl group of lyso PCs. As for tissue distribution in human, mouse, and rat, A-C1 mRNA was abundantly expressed in testis, skeletal muscle, brain, and heart. These results demonstrate that A-C1 is a novel phospholipid-metabolizing enzyme. Moreover, the fact that all five members of the HRASLS subfamily, including A-C1, show similar catalytic properties strongly suggests that these proteins constitute a new class of enzymes showing PLA½ and acyltransferase activities.

Effects of exposure to a time-varying 1.5 T magnetic field on the neurotransmitter-activated increase in intracellular Ca(2+) in relation to actin fiber and mitochondrial functions in bovine adrenal chromaffin cells.

BACKGROUND: It has been reported that exposure to electromagnetic fields influences intracellular signal transduction. We studied the effects of exposure to a time-varying 1.5 T magnetic field on membrane properties, membrane cation transport and intracellular Ca(2+) mobilization in relation to signals. We also studied the mechanism of the effect of exposure to the magnetic field on intracellular Ca(2+) release from Ca(2+) stores in adrenal chromaffin cells. METHODS: We measured the physiological functions of ER, actin protein, and mitochondria with respect to a neurotransmitter-induced increase in Ca(2+) in chromaffin cells exposed to the time-varying 1.5 T magnetic field for 2h. RESULTS: Exposure to the magnetic field significantly reduced the increase in [Ca(2+)]i. The exposure depolarized the mitochondria membrane and lowered oxygen uptake, but did not reduce the intracellular ATP content. Magnetic field-exposure caused a morphological change in intracellular F-actin. F-actin in exposed cells seemed to be less dense than in control cells, but the decrease was smaller than that in cytochalasin D-treated cells. The increase in G-actin (i.e., the decrease in F-actin) due to exposure was recovered by jasplakinolide, but inhibition of Ca(2+) release by the exposure was unaffected. CONCLUSIONS AND GENERAL SIGNIFICANCE: These results suggest that the magnetic field-exposure influenced both the ER and mitochondria, but the inhibition of Ca(2+) release from ER was not due to mitochondria inhibition. The effect of eddy currents induced in the culture medium may indirectly influence intracellular actin and suppress the transient increase in [Ca(2+)]i.

High-level production and purification of clostripain expressed in a virulence-attenuated strain of Clostridium perfringens.

Clostripain (CLO) produced by Clostridium histolyticum is an arginine-specific endopeptidase with the potential for applicability to diverse medical and industrial uses. In this study, we developed an expression system allowing high-level production and efficient purification of recombinant CLO (rCLO). Our expression system comprises pCLO, an rCLO expressing vector, and Clostridium perfringens 13Δ6, an in-frame deletion strain as to six genes encoding major virulence factors and secretory proteins. rCLO was purified from the culture supernatant of C. perfringens 13Δ6/pCLO by ammonium sulfate precipitation, hydroxyapatite chromatography, and affinity chromatography on benzamidine-Sepharose. From 200 ml of culture supernatant 4.5 mg of purified rCLO was obtained. N-Terminal amino acid sequencing and molecular mass determination of the purified rCLO and commercially available CLO revealed that the two enzymes have identical subunits, a 38.1-kDa heavy chain and a 15.0-kDa light chain, indicating that rCLO is processed in the same manner as CLO. Analysis of the enzymatic activities toward N-benzoyl-L-arginine p-nitroanilide and acyl-L-lysine p-nitroanilide showed that rCLO and CLO exhibit strict specificity for arginine at the P1 position, and that the specific activity of the former is approximately 2-fold higher than that of the latter. These results indicate that the new method involving a virulence-attenuated C. perfringens strain is useful for preparing large amounts of high-grade rCLO.

Relationship between Epidermal Growth Factor Receptor Mutations and Adverse Events in Non-Small Cell Lung Cancer Patients treated with Afatinib.

Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors such as afatinib are used for non-small cell lung cancer (NSCLC) and show varying efficacy depending on EGFR gene mutation. Few studies have examined the relationship between EGFR gene mutations and the adverse events of afatinib in NSCLC. This retrospective study included 32 Japanese patients with NSCLC with EGFR gene mutation who were treated with afatinib between May 2014 and August 2018 at Kagawa University Hospital. Among the 32 Japanese patients with NSCLC treated with afatinib, 19 patients were positive for exon 19 deletion mutation (Del 19) and 13 patients were negative for Del 19. The incidence of grade ≥ 2 skin rash was slightly higher in patients positive for Del 19 (42.1% vs. 7.7%, P = 0.050). No significant differences were detected in other adverse events between the two patient groups. Patients positive for Del 19 also showed significantly longer median progression-free survival (288 vs. 84 days, P = 0.049). Our study indicates a higher incidence of skin rash associated with afatinib treatment in Japanese patients with NSCLC positive for Del 19 compared with patients without Del 19. The Del 19 positive patient group also showed better progression-free survival. J. Med. Invest. 68 : 125-128, February, 2021.

Involvement of acid ceramidase in the degradation of bioactive N-acylethanolamines.

Bioactive N-acylethanolamines (NAEs) include palmitoylethanolamide, oleoylethanolamide, and anandamide, which exert anti-inflammatory, anorexic, and cannabimimetic actions, respectively. The degradation of NAEs has been attributed to two hydrolases, fatty acid amide hydrolase and NAE acid amidase (NAAA). Acid ceramidase (AC) is a lysosomal enzyme that hydrolyzes ceramide (N-acylsphingosine), which resembles NAAA in structure and function. In the present study, we examined the role of AC in the degradation of NAEs. First, we demonstrated that purified recombinant human AC can hydrolyze various NAEs with lauroylethanolamide (C12:0-NAE) as the most reactive NAE substrate. We then used HEK293 cells metabolically labeled with [14C]ethanolamine, and revealed that overexpressed AC lowered the levels of 14C-labeled NAE. As analyzed with liquid chromatography-tandem mass spectrometry, AC overexpression decreased the amounts of different NAE species. Furthermore, suppression of endogenous AC in LNCaP prostate cells by siRNA increased the levels of various NAEs. Lastly, tissue homogenates from mice genetically lacking saposin D, a presumable activator protein of AC, showed much lower hydrolyzing activity for NAE as well as ceramide than the homogenates from wild-type mice. These results demonstrate the ability of AC to hydrolyze NAEs and suggest its physiological role as a third NAE hydrolase.

[Investigation of Successful Eyedrop Instillation Rates and Analysis of Drop Positions Using High-speed Digital Video Recording System].

We investigated the success rates of eyedrop instillation and the distance between the cornea and the dropper tip in 100 volunteers using high-speed digital video recording. Past eyedrop adherence studies assumed that instillation occurred without failure. The ideal distance between the cornea and dropper tip remained unclear, although the general estimate was approximately 2.54 cm (1 inch). This study was approved by the Institutional Review Boards of all participating medical institutions, and all volunteers provided written, informed consent. Successful instillation was defined as when 1 drop fell accurately into the eye on the first attempt. The instillation of ≥2 drops or drops delivered outside the eye was considered a failure. The distance between the eye and dropper tip was measured using still images from a paused digital video camera and a digital ruler. Forty percent of the volunteers instilled eyedrops without instructions from ophthalmologists, pharmacists, or other healthcare workers. When the images were analyzed, the success rate of the first instillation was 70.1%. When the eye was arbitrarily divided into 9 sections, most of the drop sites were the iris or the center of the eye. The distance between the dropper tip and cornea was 2.62±1.75 (median 2.20) cm. These results indicate that the generally recommended distance is usually followed. The successful instillation rate based on the distance from the dropper tip to the cornea was 77% at 1.6±0.88 cm and 54.9% at 4.8±1.25 cm.

Relationship between epidermal growth factor receptor mutations and skin rash in non-small cell lung cancer patients.

Several reports have investigated relationships between epidermal growth factor receptor (EGFR) mutations and the efficacy of EGFR-tyrosine kinase inhibitors (TKIs) in EGFR-mutant non-small cell lung cancer; however, there have been insufficient analyses of relationships between EGFR mutations and adverse reactions. This study investigated the relationships between EGFR mutations and skin rash. We first compared skin rash grades between different mutations, then tested factors possibly affecting skin rash by multivariate analysis. The main outcome measure was the significant difference in incidence of skin rash between each group with different mutations. Our study suggested that the risk of skin rash is low in patients with exon 19 deletion mutations who are taking EGFR-TKIs, whereas it is high in those with exon 21 point mutations. These results will be useful indicators for instructions regarding daily examinations, skin care, and use of oral antibiotics or topical steroids in patients taking EGFR-TKIs with skin rash.

Dose adjustment of phenytoin for comedication in Japanese patients with epilepsy.

This study sought a suitable physiological parameter related to daily phenytoin (PHT) dose (D) providing a steady-state serum concentration (Ct) and analyzed the influences of coadministered antiepileptic drugs on Ct quantitatively to adjust PHT dose. Data were derived from a total of 368 patients with epilepsy treated with multiple oral administrations of PHT. Phenobarbital, carbamazepine, valproic acid, zonisamide, clonazepam, and ethosuximide were coadministered. For the administration of PHT alone, 4 types of parameter, that is, total body weight, total body water volume, body surface area, and extracellular water volume (VECW) were examined. Then, a Michaelis-Menten kinetic model was postulated including VECW, which was assumed to detect the effect of the coadministered drug quantitatively. Adopting VECW as a transforming factor, the concentration to dose (L:D) ratio [Ct/(D/VECW)] was independent of the patient's age and gender in relation to Ct and expressed as Ct/(D/VECW) = 0.0245 x Ct + 0.076. Analysis clarified that ratios were estimated as 0.90, 0.91, 0.89, and 0.84 for phenobarbital, carbamazepine, valproic acid, and zonisamide, respectively, to maintain the same Ct concentration of PHT. Influences were not detected as the number (> or =2) of coadministered drugs increased, regardless of factor type. PHT clearance changed in an age-dependent manner and was usually poorly correlated with weight-based doses. VECW was more closely correlated with age-dependent changes in physiological parameters such as clearance. VECW was considered to remove the influence of age on clearance, and estimated ratios could be used for all age groups. In the case of the addition or removal of concomitant treatment with antiepileptic drugs in the same patient, the daily PHT dose was calculated using the value of each ratio or its reciprocal. Our results could be helpful in determining PHT dosing.