Quantitation of Plasma Membrane Drug Transporters in Kidney Tissue and Cell Lines Using a Novel Proteomic Approach Enabled a Prospective Prediction of Metformin Disposition.

The successful prospective incorporation of in vitro transporter kinetics in physiologically based pharmacokinetic (PBPK) models to describe drug disposition remains challenging. Although determination of scaling factors to extrapolate in vitro to in vivo transporter kinetics has been facilitated by quantitative proteomics, no robust assessment comparing membrane recoveries between different cells/tissues has been made. HEK293 cells overexpressing OCT2, MATE1, and MATE2K or human kidney cortex were homogenized and centrifuged to obtain the total membrane fractions, which were subsequently subjected to liquid-liquid extraction followed by centrifugation and precipitation to isolate plasma membrane fractions. Plasma membrane recoveries determined by quantitation of the marker Na+/K+-ATPase in lysate and plasma membrane fractions were ≤20% but within 3-fold across different cells and tissues. A separate study demonstrated that recoveries are comparable between basolateral and apical membranes of renal proximal tubules, as measured by Na+/K+-ATPase and γ-glutamyl transpeptidase 1, respectively. The plasma membrane expression of OCT2, MATE1, and MATE2K was quantified and relative expression factors (REFs) were determined as the ratio between the tissue and cell concentrations. Corrections using plasma membrane recovery had minimal impact on REF values (<2-fold). In vitro transporter kinetics of metformin were extrapolated to in vivo using the corresponding REFs in a PBPK model. The simulated metformin exposures were within 2-fold of clinical exposure. These results demonstrate that transporter REFs based on plasma membrane expression enable a prediction of transporter-mediated drug disposition. Such REFs may be estimated without the correction of plasma membrane recovery when the same procedure is applied between different matrices. SIGNIFICANCE STATEMENT: Transporter REFs based on plasma membrane expression enable in vitro-in vivo extrapolation of transporter kinetics. Plasma membrane recoveries as determined by the quantification of sodium-potassium adenosine triphosphatase were comparable between the in vitro and in vivo systems used in the present study, and therefore had minimal impact on the transporter REF values.

Differential effects of dexamethasone and roflumilast on asthma in mice with or without short cigarette smoke exposure.

Appropriate drug treatment for smoking asthmatics is uncertain because most smokers with asthma are less sensitive to treatment with glucocorticoids compared with non-smokers with asthma. We hypothesized that roflumilast (Rof), a selective phosphodiesterases-4 inhibitor regarded as an add-on therapy for chronic obstructive pulmonary disease, might be more effective than glucocorticoids for improving asthma in smokers. To investigate this hypothesis, we compared the therapeutic effects of dexamethasone (Dex) and Rof in a mouse model of ovalbumin-induced asthma with or without concurrent cigarette smoke (CS) exposure for 2 weeks. We found that recurrent asthma attacks increased lung tissue resistance. CS exposure in asthmatic mice decreased the central airway resistance, increased lung compliance, and attenuated airway hyper-responsiveness (AHR). CS exposure in asthmatic mice also increased the number of neutrophils and macrophages in the bronchoalveolar fluid. Treatment with Dex in asthmatic mice without CS exposure reduced airway resistance, AHR and airway eosinophilia. In asthmatic mice with CS exposure, however, Dex treatment unexpectedly increased lung tissue resistance and restored AHR that had been otherwise suppressed. Dex treatment in asthmatic mice with CS exposure inhibited eosinophilic inflammation but conversely exacerbated neutrophilic inflammation. On the other hand, treatment with Rof in asthmatic mice without CS exposure reduced airway resistance and airway eosinophilia, although the inhibitory effect of Rof on AHR was unremarkable. In asthmatic mice with CS exposure, Rof treatment did not exacerbate lung tissue resistance but modestly restored AHR, without any significant effects on airway inflammation. These results suggest that CS exposure mitigates sensitivity to both Dex and Rof. In asthmatic mice with CS exposure, Dex is still effective in reducing eosinophilic inflammation but increases lung tissue resistance, AHR and neutrophilic inflammation. Rof is ineffective in improving lung function and inflammation in asthmatic mice with CS exposure. This study did not support our initial hypothesis that Rof might be more effective than glucocorticoids for improving asthma in smokers. However, glucocorticoids may have a detrimental effect on smoking asthmatics.

AI-based forecasting of ethanol fermentation using yeast morphological data.

Several industries require getting information of products as soon as possible during fermentation. However, the trade-off between sensing speed and data quantity presents challenges for forecasting fermentation product yields. In this study, we tried to develop AI models to forecast ethanol yields in yeast fermentation cultures, using cell morphological data. Our platform involves the quick acquisition of yeast morphological images using a nonstaining protocol, extraction of high-dimensional morphological data using image processing software, and forecasting of ethanol yields via supervised machine learning. We found that the neural network algorithm produced the best performance, which had a coefficient of determination of >0.9 even at 30 and 60 min in the future. The model was validated using test data collected using the CalMorph-PC(10) system, which enables rapid image acquisition within 10 min. AI-based forecasting of product yields based on cell morphology will facilitate the management and stable production of desired biocommodities.

Determining particle depth positions and evaluating dispersion using astigmatism PTV with a neural network.

Herein, a calibration procedure to determine the depth positions of particles in a microfluidic channel via astigmatism particle tracking velocimetry (APTV) has been described. A neural network model focusing on the geometrical parameters of distorted particle images was developed to calibrate APTV. To demonstrate the efficiency of this procedure, the Poiseuille flow and depth of the particles, and dispersions in the microchannel were studied. The depth positions were determined with an uncertainty of ±1µm. The present results suggest that the particle position dispersion could be a result of the degree of particle image deformation and its deviation.

Promoted performance of microbial fuel cells using Escherichia coli cells with multiple-knockout of central metabolism genes.

The effect of central metabolic activity of Escherichia coli cells acting as biocatalysts on the performance of microbial fuel cells (MFCs) was studied with glucose used as the energy source. Milliliter-scale two-chambered MFCs were used with 2-hydroxy-1,4-naphthoquinone (HNQ) as an electron mediator. Among the single-gene deletions examined, frdA, pdhR, ldhA, and adhE increased the average power output of the constructed MFC. Next, multiple-gene knockout mutants were constructed using P1 transduction. The Δ5 (ΔfrdAΔpdhRΔldhAΔadhEΔpta) strain showed the highest ave. power output (1.82 mW) and coulombic efficiency (21.3%). Our results show that the combination of multiple-gene knockout in E. coli cells leads to the development of an excellent catalyst for MFCs. Finally, preventing a decrease in the pH of the anodic solution was a key factor for improving the power output of the Δ5 strain, and a maximum ave. power output of 2.21 mW was achieved with 5% NaHCO3 in the buffer. The ave. power density of the constructed MFC was 0.27 mW/cm3, which is comparable to an enzymatic fuel cell of a Milliliter-scale using glucose dehydrogenase.

Translation of In Vitro Transport Inhibition Studies to Clinical Drug-Drug Interactions for Glecaprevir and Pibrentasvir.

Glecaprevir and pibrentasvir are oral direct-acting antiviral agents approved in combination for treatment of chronic hepatitis C viral infection. In vitro studies identified the combination as potentially clinically relevant inhibitors of the efflux transporters P-glycoprotein (P-gp), breast cancer resistance protein (BCRP), and the hepatic uptake transporters organic anion transporting polypeptide (OATP) 1B1 and OATP1B3. Glecaprevir inhibited P-gp, BCRP, OATP1B1, and OATP1B3 with IC50 values of 0.33, 2.3, 0.017, and 0.064 µM, respectively. Pibrentasvir inhibited P-gp, BCRP, and OATP1B1 with IC50 values of 0.036, 14, and 1.3 µM, respectively. Neither agent inhibited organic cation transporter (OCT) 1, OCT2, organic anion transporter (OAT) 1, OAT3, multidrug and toxin extrusion (MATE) 1, or MATE2K. Open-label phase 1 clinical drug-drug interaction studies were conducted in healthy subjects to evaluate interaction potential of glecaprevir/pibrentasvir and coadministered selective substrates for P-gp (digoxin, dabigatran etexilate, and sofosbuvir), BCRP (rosuvastatin and sofosbuvir), and OATP1B1/3 (pravastatin and rosuvastatin). The pharmacokinetic maximum plasma concentration (C max) and area under the concentration-time curve (AUC) parameters were evaluated for probe substrates alone and in combination with glecaprevir/pibrentasvir. The C max central values increased by 72%, 105%, 123%, 462%, and 66% for digoxin, dabigatran, pravastatin, rosuvastatin, and sofosbuvir, respectively, and the AUC central values increased by 48%, 138%, 130%, 115%, and 125% for digoxin, dabigatran, pravastatin, rosuvastatin, and sofosbuvir, respectively. Exposure of sofosbuvir metabolite GS-331007 (nucleoside analog) was similar with or without glecaprevir/pibrentasvir. The outcomes of the clinical drug-drug interaction studies confirmed clinically relevant inhibition of P-gp, BCRP, and OATP1B1/3, and were used to provide dosing guidance for the concomitant use of glecaprevir/pibrentasvir with relevant transporter substrates.

Quality of life after living donor liver transplant for biliary atresia in Japan.

BACKGROUND: Health-related quality of life (HRQOL) is an important outcome in solid organ transplantation. This study evaluated and explored the factors of generic and transplant-specific HRQOL in Japanese pediatric and adolescent patients with biliary atresia (BA) after living donor liver transplant (LDLT). METHODS: A cross-sectional survey using anonymous questionnaires was completed between April and July 2015. Patient medical records were accessed. The Japanese version of Pediatric Quality of Life InventoryTM Generic Core Scales and Transplant Modules (child self-report and parent proxy-report) was administered. RESULTS: Participants consisted of 75 patients (mean age at survey, 9.6 years) and 74 parents. Japanese patients reported higher generic and transplant-specific HRQOL (total score) than that reported by US patients with BA after LT (US I; age at survey, 7.2 years) and by US patients after solid organ transplant (US II; age at survey, 11.3 years; LT, 53.8%; effect size, 0.55-0.96). Japanese parents, however, rated their children's generic HRQOL (total score) similar to that rated by the US I and II parents (0.13 and 0.30, respectively) and reported lower transplant-specific HRQOL (total score) than that reported by US II (0.26). Although the number of types of prescribed drugs was a common factor in HRQOL, most demographic and medical factors (e.g. child's age at survey and consultation frequency) varied with reporter (i.e. patients and parents). CONCLUSIONS: The levels and factors of generic and transplant-specific HRQOL of Japanese pediatric and adolescent patients with BA after LDLT varied with reporter (i.e. patients or parents).

A Qualitative Assessment of Adolescent Girls' Perception of Living with Congenital Heart Disease: Focusing on Future Pregnancies and Childbirth.

PURPOSE: Congenital heart disease (CHD) is the most common birth anomaly in Japan, occurring in approximately 10.6 of every 1,000 live births. Advancements in medical and surgical care have increased births by women diagnosed with CHD. The study's purpose was to examine the perceptions of pregnancy and childbirth among adolescent girls with CHD. DESIGN AND METHODS: Twelve semi-structured interviews were conducted, and the data were analyzed using a modified grounded-theory approach. RESULTS: Three categories and 16 subcategories were extracted. Adolescent girls with CHD reported feelings of distress and anxiety while struggling with their disease, and feared how their disease might negatively influence their future pregnancy. These concerns were related to a desire to become familiar with CHD. The girls also explored how their disease would be managed during pregnancy and childbirth. Overall, these perceptions were influenced by the girls' acceptance of their disease, and support from family, friends, and healthcare professionals. CONCLUSIONS: Healthcare professionals might assess adolescent girls' awareness of their disease before discussing pregnancy and childbirth risks. To encourage them to understand and cope with their disease, healthcare professionals might provide interventions tailored to the timing, stage, and degree of pregnancy and childbirth awareness. This could allow safer life planning, especially concerning pregnancy and childbirth decisions. PRACTICE IMPLICATIONS: To address adolescent girls' needs, healthcare professionals should continuously assess their awareness of pregnancy and childbirth as well as their psychological status, alongside CHD issues.

Hypercapnia Accelerates Adipogenesis: A Novel Role of High CO2 in Exacerbating Obesity.

Obesity is a major risk factor for the development of obstructive sleep apnea (OSA) and obesity hypoventilation syndrome (OHS), which manifest as intermittent hypercapnia and sustained plus intermittent hypercapnia, respectively. In this study, we investigated whether CO2 affects adipocyte differentiation (adipogenesis) and maturation (hypertrophy). Human visceral or subcutaneous preadipocytes were grown to confluence and then induced to differentiate to adipocytes under hypocapnia, normocapnia, and hypercapnia with or without hypoxia. Adipogenesis was also induced under intermittent or sustained hypercapnia. Differentiated adipocytes were maintained to maturity under normocapnia or hypercapnia. Our main findings are as follows: (1) hypercapnia accelerated adipogenesis in visceral and subcutaneous preadipocytes, whereas hypocapnia inhibited adipogenesis; (2) hypercapnia did not affect adipocyte hypertrophy; (3) hypercapnia-accelerated adipogenesis was independent of extracellular acidosis, oxygen concentration, or either intermittent or sustained exposure to high CO2; and (4) the mechanisms underlying hypercapnia-accelerated adipogenesis involved increased production of cyclic adenosine monophosphate (cAMP) via soluble adenylyl cyclase, leading to the activation of protein kinase A and exchanger protein directly activated by cAMP, which, in turn, activated proadipogenic transcription factors, such as cAMP response element binding protein, CCAAT/enhancer binding protein ß, and peroxisome proliferator-activated receptor γ. This study reveals a novel role of high CO2 in promoting adipogenesis, which provides mechanistic clues to a pathoetiological interaction between OSA/OHS and obesity. Our data suggest a vicious cycle of disease progression via the following mechanism: OSA/OHS → hypoventilation → hypercapnia → increased adipogenesis → increased fat mass → exacerbated OSA/OHS.

Improvement of metabolic disorders by an EP2 receptor agonist via restoration of the subcutaneous adipose tissue in pulmonary emphysema.

Chronic obstructive pulmonary disease (COPD) is often associated with co-morbidities. Metabolic disorders like hyperlipidemia and diabetes occur also in underweight COPD patients, although the mechanism is uncertain. Subcutaneous adipose tissue (SAT) plays an important role in energy homeostasis, since restricted capacity to increase fat cell number with increase in fat cell size occurring instead, is associated with lipotoxicity and metabolic disorders. The aim of this study is to show the protective role of SAT for the metabolic disorders in pulmonary emphysema of a murine model. We found ectopic fat accumulation and impaired glucose homeostasis with wasting of SAT in a murine model of elastase-induced pulmonary emphysema (EIE mice) reared on a high-fat diet. ONO-AE1-259, a selective E-prostanoid (EP) 2 receptor agonist, improved angiogenesis and subsequently adipogenesis, and finally improved ectopic fat accumulation and glucose homeostasis with restoration of the capacity for storage of surplus energy in SAT. These results suggest that metabolic disorders like hyperlipidemia and diabetes occured in underweight COPD is partially due to the less capacity for storage of surplus energy in SAT, though the precise mechanism is uncertained. Our data pave the way for the development of therapeutic interventions for metabolic disorders in emphysema patients, e.g., use of pro-angiogenic agents targeting the capacity for storage of surplus energy in the subcutaneous adipose tissue.

Validation of a total IC50 method which enables in vitro assessment of transporter inhibition under semi-physiological conditions.

1. Accurate predictions of clinical transporter-mediated drug-drug interactions (DDI) from in vitro data can be challenging when compounds have poor solubility and/or high nonspecific binding. Additionally, current DDI predictions for compounds with high plasma-protein binding assume that the unbound fraction in plasma is 0.01, if the experimental value is less than 0.01 or cannot be determined. This approach may result in an overestimation of DDI risk. To overcome these challenges, it may be beneficial to conduct inhibition studies under physiologically relevant conditions. 2. Here, IC50 values, determined in the presence of 4% bovine serum albumin approximating human plasma albumin concentrations, were successfully used to predict DDI for uptake transporters, OATP1B1/1B3, OCT1/2, OAT1/3 and MATE1/2K. 3. The IC50 values of reference inhibitors with 4% bovine serum albumin, considered total IC50, were comparable to the predicted values based on nominal IC50 values determined under protein-free conditions and unbound fraction in plasma. Calculation of R-total and Cmax/IC50,total values using total plasma exposure and total IC50 values explained the clinical DDI or absence of it for these inhibitors. 4. These results suggest that IC50 determinations in the presence of 4% albumin can be used, in the context of clinical total exposure, to predict DDI involving uptake transporters.

Development of the Japanese version of the Pediatric Quality of Life Inventory™ Transplant Module.

BACKGROUND: Health-related quality of life (HRQOL) is an important outcome in pediatric solid organ transplantation. Considering the emerging problems after transplantation, an evaluation of transplant-specific aspects of HRQOL is essential, but no validated HRQOL measure is available in Japan. The aim of this study was therefore to develop the Japanese version of the Pediatric Quality of Life Inventory™ (PedsQL) Transplant Module Child Self-Report and to investigate its feasibility, reliability, and validity. METHODS: Based on the PedsQL linguistic validation process, the Japanese version of the PedsQL Transplant Module was developed through translation and cognitive interviews (patient testing). The scale's reliability and validity were investigated, using statistical analyses of field tests of the target population. RESULTS: Eighty-seven pairs of pediatric liver-transplant recipients and their parents participated in the field test. The pediatric patients completed the measure in 3-7 min, and the rate of missing items was low (0.27%). Excellent internal consistency and test-retest reliability were confirmed. Known-groups validity, concurrent validity, and convergent and discriminant validity also were confirmed. CONCLUSIONS: Excellent feasibility, reliability, and validity of this Japanese self-report version of the PedsQL Transplant Module Child Self-Report were verified. As a measure of transplant-specific aspects of HRQOL in Japanese pediatric patients who have undergone organ transplants, the Japanese version of the PedsQL Transplant Module is appropriate for use in clinical and research settings.

Health-related quality of life in parents of pediatric solid organ transplant recipients in Japan.

Few studies have examined HRQOL in pediatric Tx recipients' parents. This study investigated HRQOL in these parents and relationships between HRQOL and perceived burden of nurturing, family functioning, and social support. Self-report anonymous questionnaires and a survey of medical records were completed between September and December 2013. The SF-36v2, which evaluates physical, psychological, and social health, was used to measure HRQOL. While values for physical and psychological health were higher than standard values (Cohen's d = 0.34 and 0.17, respectively), social health scores were lower (d = 0.21). "Parental consultation unrelated to donation" (standardized partial regression coefficient: ß = -0.52) was associated with physical health. "Family functioning" and "Commuting time between home and primary follow-up hospital" (ß = 0.57 and -0.31) were related to psychological health. "Total score for perceived burden of nurturing" (ß = -0.31) was related to social health. Regarding parental HRQOL, while physical and psychological health was favorable, social health was impaired. In clinical practice, interventions targeting parents' physical conditions and facilitation of community and family understanding and support to share recipients' nurturing are important in improving parental HRQOL.

Parents' quality of life and family functioning in pediatric organ transplantation.

Solid organ transplantation is an important treatment option for pediatric patients in end-stage organ failure. The impact of pediatric organ transplantation on parents' quality of life and family functioning has been found to be substantial, but findings on this topic have not previously been consolidated. Thirty-one studies were selected for analysis after a database search on this topic. We present future research questions and suggestions to improve clinical practice based on the integration of this knowledge.

Clinical factors associated with negative urinary antigen tests implemented for the diagnosis of community-acquired pneumococcal pneumonia in adult patients.

OBJECTIVE: This study investigated clinical factors associated with negative urinary antigen tests (UAT) implemented for the diagnosis of pneumococcal community-acquired pneumonia (CAP) in adult patients. SUBJECTS AND METHODS: We reviewed the medical records of 755 adult patients who completed the UAT in our hospital between 2009 and 2012. Of these, we evaluated 63 patients with bacteriologically confirmed definite pneumococcal CAP (33 were UAT-positive, and 30 were UAT-negative). RESULTS: There was no significant difference between the UAT-positive and the UAT-negative patients regarding age, dehydration, respiratory failure, orientation, blood pressure (ADROP) score (the CAP severity score proposed by the Japanese Respiratory Society), gender, white blood cell counts, liver/kidney function tests, or urinalysis. However, serum C-reactive protein (CRP) concentrations were 31% lower in the UAT-negative patients than in the UAT-positive patients (p = 0.02). Furthermore, the prothrombin time-international normalized ratio was 50% higher in the UAT-negative patients than in the UAT-positive patients, although the difference did not reach statistical significance (p = 0.06). The prevalence of comorbidities was similar in both UAT-positive and UAT-negative patients. However, warfarin had been prescribed in 8 (27%) of the UAT-negative patients compared to only 1 (3%) of the UAT-positive patients (odds ratio = 11.6; p = 0.01). CONCLUSIONS: These results suggested that low serum CRP concentrations and the use of warfarin increased the possibility with which false-negative UAT results occurred in these patients with pneumococcal CAP.

Promotion of adipogenesis by an EP2 receptor agonist via stimulation of angiogenesis in pulmonary emphysema.

Body weight loss is a common manifestation in patients with chronic obstructive pulmonary disease (COPD), particularly those with severe emphysema. Adipose angiogenesis is a key mediator of adipogenesis and use of pro-angiogenic agents may serve as a therapeutic option for lean COPD patients. Since angiogenesis is stimulated by PGE2, we examined whether ONO-AE1-259, a selective E-prostanoid (EP) 2 receptor agonist, might promote adipose angiogenesis and adipogenesis in a murine model of elastase-induced pulmonary emphysema (EIE mice). Mice were intratracheally instilled with elastase or saline, followed after 4 weeks by intraperitoneal administration of ONO-AE1-259 for 4 weeks. The subcutaneous adipose tissue (SAT) weight decreased in the EIE mice, whereas in the EIE mice treated with ONO-AE1-259, the SAT weight was largely restored, which was associated with significant increases in SAT adipogenesis, angiogenesis, and VEGF protein production. In contrast, ONO-AE1-259 administration induced no alteration in the weight of the visceral adipose tissue. These results suggest that in EIE mice, ONO-AE1-259 stimulated adipose angiogenesis possibly via VEGF production, and thence, adipogenesis. Our data pave the way for the development of therapeutic interventions for weight loss in emphysema patients, e.g., use of pro-angiogenic agents targeting the adipose tissue vascular component.

In vitro OATP1B1 and OATP1B3 inhibition is associated with observations of benign clinical unconjugated hyperbilirubinemia.

1. Transient benign unconjugated hyperbilirubinemia has been observed clinically with several drugs including indinavir, cyclosporine, and rifamycin SV. Genome-wide association studies have shown significant association of OATP1B1 and UGT1A1 with elevations of unconjugated bilirubin, and OATP1B1 inhibition data correlated with clinical unconjugated hyperbilirubinemia for several compounds. 2. In this study, inhibition of OATP1B3 and UGT1A1, in addition to OATP1B1, was explored to determine whether one measure offers value over the other as a potential prospective tool to predict unconjugated hyperbilirubinemia. OATP1B1 and OATP1B3-mediated transport of bilirubin was confirmed and inhibition was determined for atazanavir, rifampicin, indinavir, amprenavir, cyclosporine, rifamycin SV and saquinavir. To investigate the intrinsic inhibition by the drugs, both in vivo Fi (fraction of intrinsic inhibition) and R-value (estimated maximum in vivo inhibition) for OATP1B1, OATP1B3 and UGT1A1 were calculated. 3. The results indicated that in vivo Fi values >0.2 or R-values >1.5 for OATP1B1 or OATP1B3, but not UGT1A1, are associated with previously reported clinical cases of drug-induced unconjugated hyperbilirubinemia. 4. In conclusion, inhibition of OATP1B1 and/or OATP1B3 along with predicted human pharmacokinetic data could be used pre-clinically to predict potential drug-induced benign unconjugated hyperbilirubinemia in the clinic.

Translation and Testing the Reliability and Validity of a Japanese Version of the Paternal Antenatal Attachment Scale (PAAS-J).

Background and Purpose: This study aimed to translate and validate a Japanese version of the Paternal Antenatal Attachment Scale (PAAS-J). Methods: The PAAS-J was translated through a pilot study and a survey of fathers with pregnant partners. Results: The survey involved 189 fathers. A confirmatory factor analysis was performed, but the model fit was poor. Therefore, an exploratory factor analysis (EFA) was performed. Based on the results of the EFA, three items with low interitem correlations and factor loadings were deleted, and a 13-item scale consisting of 2 domains was created. Coefficient alpha was .80. The intraclass correlation coefficient of the retest method was .80, confirming its reliability. Conclusions: The PAAS-J was found to be reliable and valid.

Effective treatment of steroid-resistant immune checkpoint inhibitor pneumonitis with mycophenolate mofetil.

Insufficient evidence is available for treating steroid-resistant immune checkpoint inhibitor pneumonitis (CIP). Although guidelines recommend the use of immunosuppressants, the efficacy of mycophenolate mofetil (MMF) has not been sufficiently verified. We report two cases of steroid-resistant CIP treated with MMF. Both patients responded to initial treatment with prednisolone (PSL), but the CIP flared up repeatedly as the steroids were gradually tapered off. Upon receiving MMF in addition to PSL, their subjective symptoms improved, and the shadows gradually disappeared, allowing for a reduction in the steroid dose. Ultimately, no CIP recurrence was observed despite discontinuing PSL and MMF. Both cases were completely resolved by treatment with MMF. This indicates that MMF may be effective in treating steroid-resistant CIP. In the future, the effects and safety of MMF should be investigated in large-scale clinical trials targeting patients with steroid-resistant CIP.

Prognostic significance of antifibrotic agents in idiopathic pulmonary fibrosis after initiation of long-term oxygen therapy.

BACKGROUND AND AIM: Idiopathic pulmonary fibrosis (IPF) is a fatal and progressive interstitial lung disease with varying degrees of hypoxemia. Long-term oxygen therapy (LTOT) is frequently used to treat hypoxemia, however the prognostic factors for better survival in IPF patients after initiation of LTOT remain unknown. METHODS: We retrospectively investigated favorable factors of survival in consecutive 55 IPF patients with chronic respiratory failure who were introduced LTOT. RESULTS: The 6-, 12-, 18-, and 24-month survival rates in IPF patients after introduction of LTOT were 70.9%, 49.0%, 45.2%, and 32.3%, respectively. Univariate analysis demonstrated that low Glasgow Prognostic Score (GPS) (hazard ratio [HR] 0.482, p=0.043) and treatment with antifibrotic agents (HR 0.401, p=0.013) were associated with favorable survival, while multivariate analysis revealed that treatment with antifibrotic agents was the independent predictor (HR 0.449, p=0.032). Moreover, IPF patients treated with antifibrotic agents with LTOT had significantly longer survival than those without antifibrotic agents (p = 0.0106). CONCLUSION: In IPF patients who were introduced LTOT, treatment with antifibrotic agents was the independent factor for favorable survival. Treatment with antifibrotic agents may improve prognosis of IPF even after initiation of LTOT.