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BACKGROUND: Drug-drug interactions (DDIs) increase the incidence of adverse drug reactions (ADRs). In a previous report, we revealed that the incidence of potential DDIs due to the same CYP molecular species in one prescription exceeds 90% among patients taking six or more drugs and that CYP3A4 markedly influences the increase in the number of potential DDIs in clinical practice. However, the factors contributing to an increased number of potential DDIs in prescriptions from multiple clinical departments remain poorly clarified. METHODS: This observational study was performed at five pharmacies in Okayama Prefecture, Japan. Patients who visited these pharmacies from 11 April 2022 to 24 April 2022 were included, except those who had prescriptions only from a single clinical department. A stratified analysis was performed to determine the incidence of CYP3A4-related potential DDIs according to the number of drugs taken. Additionally, factors associated with an increase in the number of drugs involved in CYP3A4-related potential DDIs were identified using multiple linear regression analysis. In this study, potential DDIs for the prescription data subdivided by clinical department, containing two or more drugs, were used as control data. RESULTS: Overall, 372 outpatients who received prescriptions from multiple clinical departments were included in the current study. The number of drugs contributing to CYP3A4-related potential DDIs increased with an increase in the number of clinical departments. Notably, in cases taking fewer than six drugs, prescriptions from multiple clinical departments had a higher frequency of CYP3A4-related potential DDIs than those in prescriptions subdivided by clinical department. Multiple regression analysis identified "Cardiovascular agents", "Agents affecting central nervous system", and "Urogenital and anal organ agents" as the top three drug classes that increase CYP3A4-related potential DDIs. CONCLUSION: Collectively, these results highlight the importance of a unified management strategy for prescribed drugs and continuous monitoring of ADRs in outpatients receiving prescriptions from multiple clinical departments even if the number of drugs taken is less than six.

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INTRODUCTION: Pharmacists are needed as members of oncology teams. The Japanese Society of Hospital Pharmacists (JSHP) conducts a nationwide survey annually to analyze the actual situation and generate fundamental information about hospital pharmacy practice in Japan. Using data from this large-scale survey, we described pharmacists' involvement in cancer chemotherapy. We explored the factors related to the acceleration of pharmacists' tasks or involvement in clinical practice, primarily in oncology. METHODS: Data were obtained from annual surveys conducted by JSHP from 2015 to 2020. All variables were expressed as categorical variables and tabulated. The Chi-square and Fisher's exact tests were used to compare the categorical variables. The Cochran-Armitage trend test was used to identify significant trends. RESULTS: From 2015 to 2020, 22,362 responses were recorded. After applying the exclusion criteria, 20,906 were analyzed. The proportion of hospitals enrolling pharmacists with oncology-related certifications significantly increased in all hospitals providing cancer care. Multivariable logistic regression analysis indicated that a smaller number of beds per pharmacist significantly correlated with additional fees for outpatient pharmacy services (p = 0.0002 for trend). CONCLUSION: Hospitals charging increased fees for outpatient oncology pharmacy services were associated with a smaller number of beds per pharmacist, regardless of hospital size. A balance between the number of beds and pharmacists, particularly certified oncology pharmacists, is crucial for safe and high-quality cancer treatment.

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Interstitial lung disease (ILD) is a serious adverse event caused by the administration of immune checkpoint inhibitors (ICIs). However, only few large-scale studies have explored the association among ICI use, underlying cancer type, and ILD complications. This study aimed to analyze the association between the primary cancer type and ICI-induced ILD in a cross-sectional manner using the Japanese Adverse Drug Event Report (JADER) database. Nivolumab and pembrolizumab (anti-programmed cell death 1 (PD-1) antibodies) and durvalumab, avelumab, and atezolizumab (anti-programmed cell death ligand 1 (PD-L1) antibodies) were included as ICIs in this study. Adverse events were identified based on the preferred terms of Medical Dictionary for Regulatory Activities (MedDRA) version 27.0/J listed in the Standardized MedDRA Queries (SMQ) "interstitial lung disease." The reporting odds ratio was calculated to detect the association between ICI use and ILD complications, and a signal was detected if the lower limit of the 95% confidence interval exceeded 1. In the analysis of all cancer types, a signal was detected for all ICIs except avelumab. An association between ICI and ILD was detected for all cancer types with nivolumab. However, pembrolizumab exhibited a signal only in colorectal cancer. In contrast, anti-PD-L1 antibodies displayed signals in five cancer types, excluding head and neck cancer, which was not reported in JADER. Among these cancer types, atezolizumab exhibited a signal only in breast cancer. The results of this study will help guide the safe use of ICIs based on the underlying cancer type in terms of ILD complications.

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BACKGROUND: Hospitals in Japan established the healthcare delivery system from FY 2018 to 2021 by acquiring an additional reimbursement for infection prevention (ARIP) of category 1 or 2. However, research on outcomes of ARIP applications related to the practice of hospital pharmacists is scarce. METHODS: This study assessed the activities performed by hospital pharmacists in hospitals with 100 to 299 beds, using ARIP acquirement as an indicator, using data from an annual questionnaire survey conducted in 2020 by the Japanese Society of Hospital Pharmacists on the status of hospital pharmacy departments. Out of the survey items, this study used those related to hospital functions, number of beds, number of pharmacists, whether the hospital is included in the diagnosis procedure combination (DPC) system, average length of stay, and nature of work being performed in the analysis. The relationship between the number of beds per pharmacist and state of implementation of pharmacist services or the average length of hospital stay was considered uncorrelated when the absolute value of the correlation coefficient was within 0-0.2, whereas the relationship was considered to have a weak, moderate, or strong correlation when the absolute value ranged at 0.2-0.4, 0.4-0.7, or 0.7-1, respectively. RESULTS: Responses were received from 3612 (recovery rate: 43.6%) hospitals. Of these, 210 hospitals meeting the criteria for ARIP 1 with 100-299 beds, and 245 hospitals meeting the criteria for ARIP 2 with 100-299 beds, were included in our analysis. There was a significant difference in the number of pharmacists, with a larger number in ARIP 1 hospitals. For the pharmacist services, significant differences were observed, with a more frequency in ARIP 1 hospitals in pharmaceutical management and guidance to pre-hospitalization patients, sterile drug processing of injection drugs and therapeutic drug monitoring. In DPC hospitals with ARIP 1 (173 hospitals) and 2 (105 hospitals), the average number of beds per pharmacist was 21.7 and 24.7, respectively, while the average length of stay was 14.3 and 15.4 d, respectively. Additionally, a weak negative correlation was observed between the number of pharmacist services with "Fairly well" or "Often" and the number of beds per pharmacist for both ARIP 1 (R = -0.207) and ARIP 2 (R = -0.279) DPC hospitals. Furthermore, a weak correlation (R = 0.322) between the average number of beds per pharmacist and the average length of hospital stay was observed for ARIP 2 hospitals. CONCLUSIONS: Our results suggest that lower beds per pharmacist might lead to improved pharmacist services in 100-299 beds DPC hospitals with ARIP 1 or 2. The promotion of proactive efforts in hospital pharmacist services and fewer beds per pharmacist may relate to shorter hospital stays especially in small and medium-sized hospitals with ARIP 2 when ARIP acquisition was used as an indicator. These findings may help to accelerate the involvement of hospital pharmacists in infection control in the future.

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The coronavirus disease 2019 (COVID-19) pandemic has considerably affected several social services. The Ministry of Health, Labour, and Welfare has partially revised the Pharmaceuticals and Medical Devices Law and established legislations on permanent online medication instructions. Based on these social needs, the development of human resources to provide online medication instructions is vital. Therefore, we developed a training program for providing online medication instructions in preparatory clinical education. Pharmacy students who had conducted medical interviews with standardized patients participated in the training. Educational outcomes were evaluated using an objective multiple-choice test and free description before and after practical training. The median number of correct answers on objective tests on the legislation on online medication instructions increased significantly. Based on the free description analysis, students were able to comprehend the influence of communication environment on the quality of medication instructions. Based on the results of the direct evaluation using objective testing and indirect evaluation by analyzing the free descriptions, they also acquired the skills necessary for providing online medication instructions. Therefore, this training program can contribute to mastering the provision of online medication instructions.

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BACKGROUND/AIM: Advanced glycation end products (AGEs) accumulate in the body with increasing age. However, their excessive accumulation may lead to various inflammatory and chronic diseases. While it is common for older adults to experience various comorbidities, there is a scarcity of published literature documenting the specific impact of ageing and comorbidities on AGEs in this population. The present study aimed to retrospectively evaluate the correlation among AGEs in the skin, calendar age, and comorbidities in older adults. PATIENTS AND METHODS: Accumulated AGEs in the skin were assessed by non-invasive measurement of skin autofluorescence (SAF) inside the forearm. This retrospective study included individuals who underwent SAF measurements at Shujitsu University Community Pharmacy with or without a prescription from October 2019 to October 2021. Subsequently, the associations between SAF, calendar age, comorbidities, and blood test parameters were investigated. RESULTS: SAF showed a positive correlation with calendar age for all enrolled participants; the correlation weakened for participants aged ≥50 years and plateaued for those aged ≥60 years. Furthermore, we observed a significant increase in SAF among all participants with comorbidities compared to those without comorbidities. By contrast, among participants aged ≥50 years, SAF did not show a significant association with comorbidities. However, SAF was significantly positively correlated with white blood cell (WBC) counts in these aged populations. CONCLUSION: The non-invasive assessment of SAF holds promise in evaluating changes in the physical condition associated with WBC counts among older adults.

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BACKGROUND: Information sharing among medical professionals is important for providing quality medical care. The purpose of the present study was to elucidate the actual status of information sharing between hospitals and other healthcare delivery facilities by surveying information sharing among the pharmaceutical departments of Japanese hospitals in 2020 conducted by the Japanese Society of Hospital Pharmacists. METHODS: Responses were received from 3612 (43.6%) of the 8278 target medical institutions between May 2020 and August 2020. RESULTS: The proportions of hospitals that shared information with community pharmacies, other hospitals, and long-term nursing homes were 40.6%, 36.4%, and 27.3%, respectively. While tracing reports were the most common tool used by hospitals for information sharing with community pharmacies (54.3%), drug summaries were used for sharing information with other hospitals and long-term nursing homes (77.4% and 78.0%, respectively). The proportion of hospitals sharing information with community pharmacies and other hospitals showed a tendency to increase as the number of hospital beds increased. No relationship could be established between the number of hospital beds and the proportion of hospitals sharing information with long-term nursing homes. CONCLUSION: Information between hospitals and community pharmacies was shared primarily using tracing reports, whereas information between hospitals and other hospitals and long-term nursing homes was primarily shared via drug summaries.

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WHAT IS KNOWN AND OBJECTIVE: Adverse drug reactions (ADRs) are one of the primary reasons for hospitalization. The spontaneous reporting of ADRs by healthcare professionals is important for issuing post-marketing drug safety measures. The Japanese Society of Hospital Pharmacists (JSHP) conducts a nationwide survey annually. Using data from this large-scale survey, we identified the characteristics of hospitals that reported ADRs to regulatory authorities and pharmaceutical companies. METHODS: Data were obtained from annual surveys conducted by JSHP from 2015 to 2020. All variables were expressed as categorical variables and tabulated. The Chi-square test was used to compare the categorical variables. The Cochran-Armitage trend test was used to identify significant trends in the proportion of hospitals reporting ADRs. RESULTS AND DISCUSSION: From 2015 to 2020, 22,362 responses were recorded. There was a significant increase in the proportion of hospitals that reported ADRs with an increase in number of beds and pharmacists (p < 0.0001). The proportion of hospitals reporting ADRs to regulatory authorities was also significantly higher in those charging an additional fee for pharmacist-performed ward operations and in those with an ADR data management section than in hospitals without these attributes (p < 0.0001). WHAT IS NEW AND CONCLUSION: Hospitals that submitted ADR reports to the regulatory authorities and pharmaceutical companies charged an additional fee for pharmacist-performed ward operations, had a central ADR data management section, and had fewer beds per pharmacist. This trend was similar, regardless of the size of the hospital.

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Drug-drug interactions (DDIs) are responsible for an increase in the incidence of adverse drug reactions. Although CYP is known to be involved in metabolic processes, the DDIs among three or more drugs that involve the same CYP molecular species have not been fully investigated. In this study, we retrospectively examined the relationship between the number of drugs and potential DDIs in metabolic processes involving CYPs in patients who picked up their prescribed drugs at 11 pharmacies in the Kojima Branch of the Okayama Pharmaceutical Association. We found that 66.5% of the 924 patients had potential DDIs; more than half of the patients who took six or more drugs had potential DDIs among three or more drugs. The mean number of CYP3A4-related drugs involved in potential DDIs was 3.52±1.56 in patients who took seven drugs, suggesting the need for careful monitoring of specific symptoms and blood test results for the early detection of adverse drug reactions caused by DDIs among three or more drugs.

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BACKGROUND: Pharmaceutical intervention enables safe and effective pharmacotherapy by avoiding of adverse drug reactions (ADRs) and efficacy attenuations. Many prescriptions require optimization, and pharmaceutical interventions are inextricably associated with the prevention of potential drug-related problems (DRPs). Although the analysis and understanding of pharmaceutical interventions can lead to improvement in prescription, the analysis of routine pharmaceutical interventions in Japan in insufficient. Thus, we conducted this study to understand potential DRPs by analyzing routine pharmaceutical interventions made by pharmacists in Japan. METHODS: Pharmacists register the details of pharmaceutical interventions (excluding personal patient information) in a web-based database. We classified data of pharmaceutical interventions into 13 DRP types, 43 DRP subtypes, and 10 intervention categories (e.g., avoidance of serious ADRs and renal dosing recommendations). These data were analyzed with a focus on renal dysfunction and polypharmacy. RESULTS: During the study period, 2376 pharmaceutical interventions were performed. Overall, 68.2% of pharmaceutical interventions were for patients aged over 65 years. The most frequently detected potential DRP was overdosage, followed by omission of prescription, contraindications, and duplication of a drug with similar effect. The main cause of contraindication and overdosage was renal function deterioration, and that of polypharmacy was duplication of a drug with similar effect. Using our original evidence-based approach, we found that 2376 pharmaceutical interventions prevented ADRs for 1678 drugs, with potential cost savings of up to USD 2,657,820. CONCLUSIONS: Our results indicate that the analysis of routine pharmaceutical interventions is beneficial for detecting potential DRPs. Our findings also show that, in an aging society, pharmacists have an important role in providing medication safety, with potential cost savings.

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Ulcerative colitis (UC) is a refractory disease that causes chronic inflammation or ulceration in the mucosa of the large intestine with multiple relapses. Although several drugs, including 5-aminosalicylic acid, steroids, immunosuppressants, and infliximab, are used for UC therapy, patients suffer from side effects of these drugs, and a new safer therapeutic agent is desired. Eucommia ulmoides OLIV. leaf extract (ELE) has an anti-inflammatory effect. Therefore, we examined the effect of ELE on UC using a chronic dextran sulfate sodium (DSS)-induced colitis model in mice. Chronic DSS-induced colitis was triggered by alternately repeating 5 days' DSS and 7 days' water administration in mice for 29 d. The severity of DSS-induced colitis was evaluated by daily body weight and bloody stool score, and colon length and myeloperoxidase (MPO) activity in colon tissue on day 29. ELE (3 or 9%) was administered in combination by feeding for 29 d, and the effect on colitis was evaluated. The mice given DSS exhibited chronic colitis symptoms with body weight loss, increased bloody stool score and MPO activity, and shortened colon length. Administration of 3 or 9% ELE suppressed the body weight loss, bloody stool score, colon shortening, and MPO activity in a dose-dependent manner. Histological analysis showed that the ELE-treated mice had less damages and leukocyte infiltration in the mucosal layer of the large intestine compared to DSS alone group. These results suggested that ELE has the potential to prevent the development of DSS-induced colitis and a therapeutic effect on UC in a safe manner.

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BACKGROUND: Pharmacists in Japan currently play a key role in patient hospital care. Their responsibilities include filling prescriptions, checking a patient's medication history, and providing appropriate information to other health care workers. More importantly, pharmacists' interventions can also result in reductions in adverse drug reactions (ADRs) and, ultimately, in cost savings. This study aimed to determine the economic value of such interventions at a hospital in Japan. METHODS: At a single Japanese hospital, we analyzed 1452 pharmaceutical interventions by pharmacists, including recommending antibiotic dosage regimens, attending ward rounds with multidisciplinary health providers, providing drug information, and reporting ADRs. We classified the interventions into 13 categories. Using data from the PreAVOID Report by the Japanese Society of Hospital Pharmacists, along with previous studies, we estimated the cost savings of the interventions. RESULTS: Various savings could be realized through appropriate interventions by hospital pharmacists. Based on the amount paid by the Pharmaceuticals and Medical Devices Agency, we calculated the cost savings associated with preventing serious ADRs as 21,400 USD ($) per case. The cost savings for recommendations related to transvenous antimicrobial therapy amounted to $1900 per patient. Pharmacists' interventions were able to prevent 12 cases of serious ADRs. CONCLUSIONS: Determining the economic value of pharmacists' interventions is an important means of appraising the current role of hospital pharmacists. Our evaluation demonstrates the positive economic effects of pharmacists' interventions in a hospital setting.

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BACKGROUND: Pharmaceutical interventions by community and hospital pharmacists can improve medication safety and result in financial savings. Their effect has not been fully explored in Japan. OBJECTIVE: To evaluate the economic and safety contributions of various pharmaceutical interventions by community and hospital pharmacists in Japan. SETTING: Two hospitals and eight community pharmacies in Ehime Prefecture, Japan, in 2014-2015. METHOD: Pharmacists entered data about pharmaceutical interventions via the internet, and the data were divided into 11 types of interventions. The economic impact was estimated based on the rate of avoidance of serious adverse drug reactions and the monetary cost of these reactions in the Japanese compensation system. The cost saving from adjusting prescriptions to take account of unused prescription drugs was calculated using drug prices from the national health insurance scheme. Main OUTCOME MEASURE: The number of pharmaceutical interventions and their economic impact. RESULTS The total cost savings from 500 to 509 pharmaceutical interventions by community and hospital pharmacists were US$207,126.6 and US$592,840, respectively. Community pharmacists mainly intervened to correct prescription errors. They also adjusted 135 prescriptions to take account of unused prescription drugs. This potentially improved patients' adherence and contributed to effective use of medication. Pharmaceutical interventions by hospital pharmacists facilitated avoidance of 10 serious adverse drug reactions, and included 42 transvenous antimicrobial therapy interventions, 88 interventions in cancer chemotherapy, and 47 monitoring recommendations. Hospital pharmacists helped improve patients' quality of life using more aggressive interventions besides correcting prescription errors. Over half of pharmaceutical interventions by community and hospital pharmacists contributed to avoidance of adverse drug reactions. CONCLUSION: These results suggest the importance of pharmaceutical interventions by both community and hospital pharmacists in reducing increasing medical expenses and contributing to safety and effectiveness of medication. They also suggest that community and hospital pharmacists have different roles.

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Ulcerative colitis (UC) involves chronic inflammation of the large intestine. Several agents are used to treat UC, but adverse side effects are remaining problems. We examined the effect of tropisetron as a new type of drug for UC using a dextran sulfate sodium (DSS)-induced model of colitis in mice. We developed a DSS-induced model of colitis and calculated the Disease Activity Index and colon length. We measured myeloperoxidase activity and determined the protein level and mRNA level of cytokines in the colon. DSS-induced colitis was ameliorated by administration of tropisetron and PNU282987. Pre-administration of methyllycaconitine diminished the suppressive effect of tropisetron upon DSS-induced colitis. These findings suggested that α7 nicotinic acetylcholine receptors (α7 nAChRs) were related to the suppressive effect of tropisetron on DSS-induced colitis. Additionally, stimulation of α7 nAChRs decreased the colon level of interleukin-6 and interferon-γ upon DSS administration. Furthermore, stimulation of α7 nAChRs decreased macrophage infiltration, with expression of α7 nAChR increased by DSS administration. These results suggest that the underlying mechanism of this suppressive effect on DSS-induced colitis is via stimulation of α7 nAChRs and involves suppression of expression of pro-inflammatory cytokines. Tropisetron could be a new type of therapeutic agent for UC.

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Idiopathic pulmonary fibrosis (IPF) is thought to involve inflammatory infiltration of leukocytes, lung injury induced by reactive oxygen species (ROS), in particular superoxide anion, and fibrosis (collagen deposition). No treatment has been shown to improve definitively the prognosis for IPF patients. Superoxide dismutase (SOD) catalyzes the dismutation of superoxide anion to hydrogen peroxide, which is subsequently detoxified by catalase. Lecithinized SOD (PC-SOD) has overcome clinical limitations of SOD, including low tissue affinity and low stability in plasma. In this study, we examined the effect of PC-SOD on bleomycin-induced pulmonary fibrosis. Severity of the bleomycin-induced fibrosis in mice was assessed by various methods, including determination of hydroxyproline levels in lung tissue. Intravenous administration of PC-SOD suppressed the bleomycin-induced increase in the number of leukocytes in bronchoalveolar lavage fluid. Bleomycin-induced collagen deposition and increased hydroxyproline levels in the lung were also suppressed in animals treated with PC-SOD, suggesting that PC-SOD suppresses bleomycin-induced pulmonary fibrosis. The dose-response profile of PC-SOD was bell-shaped, but concurrent administration of catalase restored the ameliorative effect at high doses of PC-SOD. Intratracheal administration or inhalation of PC-SOD also attenuated the bleomycin-induced inflammatory response and fibrosis. The bell-shaped dose-response profile of PC-SOD was not observed for these routes of administration. We consider that, compared with intravenous administration, inhalation of PC-SOD may be a more therapeutically beneficial route of administration due to the higher safety and quality of life of the patient treated with this drug.

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The main purpose of this study is to compare two different feedback controllers for the stabilization of quiet standing in humans, taking into account that the intrinsic ankle stiffness is insufficient and that there is a large delay inducing instability in the feedback loop: 1) a standard linear, continuous-time PD controller and 2) an intermittent PD controller characterized by a switching function defined in the phase plane, with or without a dead zone around the nominal equilibrium state. The stability analysis of the first controller is carried out by using the standard tools of linear control systems, whereas the analysis of the intermittent controllers is based on the use of Poincaré maps defined in the phase plane. When the PD-control is off, the dynamics of the system is characterized by a saddle-like equilibrium, with a stable and an unstable manifold. The switching function of the intermittent controller is implemented in such a way that PD-control is 'off' when the state vector is near the stable manifold of the saddle and is 'on' otherwise. A theoretical analysis and a related simulation study show that the intermittent control model is much more robust than the standard model because the size of the region in the parameter space of the feedback control gains (P vs. D) that characterizes stable behavior is much larger in the latter case than in the former one. Moreover, the intermittent controller can use feedback parameters that are much smaller than the standard model. Typical sway patterns generated by the intermittent controller are the result of an alternation between slow motion along the stable manifold of the saddle, when the PD-control is off, and spiral motion away from the upright equilibrium determined by the activation of the PD-control with low feedback gains. Remarkably, overall dynamic stability can be achieved by combining in a smart way two unstable regimes: a saddle and an unstable spiral. The intermittent controller exploits the stabilizing effect of one part of the saddle, letting the system evolve by alone when it slides on or near the stable manifold; when the state vector enters the strongly unstable part of the saddle it switches on a mild feedback which is not supposed to impose a strict stable regime but rather to mitigate the impending fall. The presence of a dead zone in the intermittent controller does not alter the stability properties but improves the similarity with biological sway patterns. The two types of controllers are also compared in the frequency domain by considering the power spectral density (PSD) of the sway sequences generated by the models with additive noise. Different from the standard continuous model, whose PSD function is similar to an over-damped second order system without a resonance, the intermittent control model is capable to exhibit the two power law scaling regimes that are typical of physiological sway movements in humans.

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A number of clinical studies have shown that non-steroidal anti-inflammatory drugs (NSAIDs) exacerbate inflammatory bowel disease; however the molecular mechanism whereby this occurs remains unclear. NSAIDs inhibit cyclooxygenase (COX), which has subtypes COX-1 and COX-2. In this study, we have examined the effect of various types of NSAIDs on the development of dextran sulfate sodium (DSS)-induced colitis, an animal model of inflammatory bowel disease. The DSS-induced colitis was worsened by administration of non-selective NSAIDs but not by COX-1 or COX-2 selective inhibitors. However, administration of a combination of both COX-1- and COX-2-selective inhibitors exacerbated the colitis. The intestinal level of PGE(2) dramatically decreased in response to administration of COX-1- and COX-2-selective inhibitors, and exogenously administered PGE(2) suppressed the exacerbation of colitis by NSAIDs. The expression of mucin proteins, which protect the intestinal mucosa, was suppressed by non-selective NSAIDs and this expression was restored by PGE(2), both in vivo and in vitro. Intestinal mucosal cell growth was inhibited by non-selective NSAIDs and this cell growth was restored by PGE(2), both in vivo and in vitro. This study provides evidence that inhibition of both COX-1 and COX-2 and the resulting dramatic decrease in the intestinal level of PGE(2) is responsible for NSAID-dependent exacerbation of DSS-induced colitis. Furthermore, expression of mucin proteins and intestinal mucosal cell growth seems to be involved in this exacerbation and its suppression by PGE(2).

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Ulcerative colitis (UC) involves intestinal mucosal damage induced by reactive oxygen species (ROS), in particular, superoxide anion. Superoxide dismutase (SOD) catalyzes dismutation of superoxide anion to hydrogen peroxide, which is subsequently detoxified by catalase. Lecithinized SOD (PC-SOD) is a new modified form of SOD that has overcome previous clinical limitations of SOD. In this study, we examined the action of PC-SOD using an animal model of UC, dextran sulfate sodium (DSS)-induced colitis. DSS-induced colitis was ameliorated by daily intravenous administration of PC-SOD. Unmodified SOD produced a similar effect but only at more than 30 times the concentration of PC-SOD. In vivo electron spin resonance analysis confirmed that the increase in the colonic level of ROS associated with development of colitis was suppressed by PC-SOD administration. The dose-response profile of PC-SOD was bell-shaped, but simultaneous administration of catalase restored the ameliorative effect at high doses of PC-SOD. Accumulation of hydrogen peroxide was observed with the administration of high doses of PC-SOD, an effect that was suppressed by the simultaneous administration of catalase. We also found that either a weekly intravenous administration or daily oral administration of PC-SOD conferred protection. These results suggest that PC-SOD achieves its ameliorative effect against colitis through decreasing the colonic level of ROS and that its ineffectiveness at higher doses is because of the accumulation of hydrogen peroxide. Furthermore, we consider that intermittent or oral administration of PC-SOD can be applied clinically to improve the quality of life of UC patients.

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