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Jaana Rytkönen Veli-Pekka Ranta Merja Kokki Hannu Kokki Heidi Hautajärvi Valtteri Rinne Aki T. Heikkinen 《Biopharmaceutics & drug disposition》2020,41(1-2):72-88
Oxycodone is an opioid analgesic with several pharmacologically active metabolites and relatively narrow therapeutic index. Cytochrome P450 (CYP) 3A4 and CYP2D6 play major roles in the metabolism of oxycodone and its metabolites. Thus, inhibition and induction of these enzymes may result in substantial changes in the exposure of both oxycodone and its metabolites. In this study, a physiologically based pharmacokinetic (PBPK) model was built using GastroPlus™ software for oxycodone, two primary metabolites (noroxycodone, oxymorphone) and one secondary metabolite (noroxymorphone). The model was built based on literature and in house in vitro and in silico data. The model was refined and verified against literature clinical data after oxycodone administration in the absence of drug–drug interactions (DDI). The model was further challenged with simulations of oxycodone DDI with CYP3A4 inhibitors ketoconazole and itraconazole, CYP3A4 inducer rifampicin and CYP2D6 inhibitor quinidine. The magnitude of DDI (AUC ratio) was predicted within 1.5-fold error for oxycodone, within 1.8-fold and 1.3–4.5-fold error for the primary metabolites noroxycodone and oxymorphone, respectively, and within 1.4–4.5-fold error for the secondary metabolite noroxymorphone, when compared to the mean observed AUC ratios. This work demonstrated the capability of PBPK model to simulate DDI of the administered compounds and the formed metabolites of both DDI victim and perpetrator. However, the predictions for the formed metabolites tend to be associated with higher uncertainty than the predictions for the administered compound. The oxycodone model provides a tool for forecasting oxycodone DDI with other CYP3A4 and CYP2D6 DDI perpetrators that may be co-administered with oxycodone. 相似文献
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Mana Kogure Naho Tsuchiya Akira Narita Takumi Hirata Naoki Nakaya Tomohiro Nakamura Atsushi Hozawa Takehito Hayakawa Nagako Okuda Naoko Miyagawa Aya Kadota Takayoshi Ohkubo Yoshitaka Murakami Kiyomi Sakata Katsuyuki Miura Akira Okayama Tomonori Okamura Hirotsugu Ueshima 《Journal of epidemiology / Japan Epidemiological Association》2021,31(2):119
BackgroundMajor reasons for long-term care insurance certification in Japan are stroke, dementia, and fracture. These diseases are reported to be associated with calcium intake. This study examined the association between calcium intake and impaired activities of daily living (ADL) using the data from NIPPON DATA90, consisting of representative sample of the Japanese population.MethodsA population-based nested case-control study was performed. A baseline survey was conducted in 1990, followed by ADL surveys of individuals ≥65 years old in 2000. Individuals with impaired ADL and selected age- and sex-matched controls were then identified. We obtained 132 pairs. Calcium intake was energy-adjusted using the residual method. The association between calcium intake and impaired ADL was examined using conditional logistic regression models. To assess the accuracy of the estimates, we conducted bootstrap analyses.ResultsThe adjusted odds ratios (ORs) for impaired ADL compared with the group with a calcium intake of <476 mg/day were 0.72 (95% confidence interval [CI], 0.37–1.40) for the 476–606 mg/day group and 0.44 (95% CI, 0.21–0.94) for the ≥607 mg/day group in 2000 (P for linear trend = 0.03). After the bootstrap analyses, the inverse relationship unchanged (median OR per 100-mg rise in calcium intake, 0.87 [1,000 resamplings]; 95% CI, 0.76–0.97).ConclusionsAfter bootstrap analyses, calcium intake was inversely associated with impaired ADL 10 years after the baseline survey.Key words: bootstrap analyses, calcium intake, impaired activities of daily living, nested case-control study, NIPPON DATA90 相似文献
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Tatsuki Ueda Ayako Kumagai Shoichi Iriguchi Yutaka Yasui Tadayo Miyasaka Kengo Nakagoshi Kazuki Nakane Keigo Saito Mari Takahashi Aki Sasaki Shinsuke Yoshida Naoko Takasu Hiroshi Seno Yasushi Uemura Koji Tamada Tetsuya Nakatsura Shin Kaneko 《Cancer science》2020,111(5):1478-1490
The use of allogeneic, pluripotent stem‐cell‐derived immune cells for cancer immunotherapy has been the subject of recent clinical trials. In Japan, investigator‐initiated clinical trials will soon begin for ovarian cancer treatment using human leukocyte antigen (HLA)‐homozygous‐induced pluripotent stem cell (iPSC)‐derived anti–glypican‐3 (GPC3) chimeric antigen receptor (CAR)‐expressing natural killer/innate lymphoid cells (NK/ILC). Using pluripotent stem cells as the source for allogeneic immune cells facilitates stringent quality control of the final product, in terms of efficacy, safety and producibility. In this paper, we describe our methods for the stable, feeder‐free production of CAR‐expressing NK/ILC cells from CAR‐transduced iPSC with clinically relevant scale and materials. The average number of cells that could be differentiated from 1.8‐3.6 × 106 iPSC within 7 weeks was 1.8‐4.0 × 109. These cells showed stable CD45/CD7/CAR expression, effector functions of cytotoxicity and interferon gamma (IFN‐γ) production against GPC3‐expressing tumor cells. When the CAR‐NK/ILC cells were injected into a GPC3‐positive, ovarian‐tumor‐bearing, immunodeficient mouse model, we observed a significant therapeutic effect that prolonged the survival of the animals. When the cells were injected into immunodeficient mice during non–clinical safety tests, no acute systemic toxicity or tumorigenicity of the final product or residual iPSC was observed. In addition, our test results for the CAR‐NK/ILC cells generated with clinical manufacturing standards are encouraging, and these methods should accelerate the development of allogeneic pluripotent stem cell‐based immune cell cancer therapies. 相似文献
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Viinikangas A Lahti S Yuan S Pietilä I Freeman R Humphris G 《Acta odontologica Scandinavica》2007,65(4):236-240
OBJECTIVE: To evaluate the psychometric properties (criterion validity, construct validity, sensitivity, and specificity) of a single-item question screening for dental anxiety in a Finnish adult population. MATERIAL AND METHODS: A total of 823 subjects, ranging in age from 18 to 87 years, answered a questionnaire comprising sections assessing the respondents' demographic profile and dental attendance patterns. A single dental anxiety question and the Modified Dental Anxiety Scale (MDAS) were included. The final response rate was 85%. RESULTS: Eight percent of the sample was highly dentally anxious using the MDAS cut-off point of 19 or above. Twelve percent of the respondents rated themselves as "very scared" on the single-item question. The percentage agreement between the single-item question and the MDAS was 93; the Kappa coefficient was 0.63. Specificity of the single question was 0.95 while sensitivity was 0.80 using the MDAS dichotomous classification. The single-item question related to age (p<0.001), gender (p<0.001), and dental attendance (p<0.001), as predicted. CONCLUSIONS: The single question has good validity, specificity, and sensitivity and may be used with confidence to assess dental fear in such situations as national health surveys or in routine dental practice where a multi-item dental anxiety questionnaire is not feasible. 相似文献
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Resistance of core materials against torsional forces on differently conditioned titanium posts 总被引:2,自引:0,他引:2
STATEMENT OF THE PROBLEM: The separation of core materials from titanium posts, which have a low modulus of elasticity, has been identified as a problem in restorative dentistry. PURPOSE: This study evaluated the resistance to torsional forces of various core materials adapted to differently conditioned titanium posts. MATERIAL AND METHODS: Seven hundred and twenty specimens were tested consisting of: 6 core materials and 5 surface conditioning techniques for 2 kinds of opaquers with 10 specimens in each group (6 x 5 x 2 x 10=600) plus 6 core materials and 2 opaquers were tested and considered as control groups on nonconditioned titanium posts, each group containing 10 specimens (6 x 2 x 10=120). The custom-made pure titanium posts were conditioned with the following products: Silicoater Classical, Silicoater MD, Rocatec, Kevloc, and Siloc surface-conditioning systems. Subsequently, 6 core materials with different compositions (Durafill, Adaptic, Coradent, Ti-Core, Hytac Aplitip, and Photac-Fil Aplitip) were applied to titanium posts that were previously coated with 2 types of light-polymerized opaquers, either Artglass or Dentacolor. Sixty air-abraded titanium posts (250 microm, 30 seconds) were used as controls for each core material. Following thermocycling (5 degrees -55 degrees C, 30 seconds, 5,000 cycles), maximum torsional forces were determined with an electronic torque movement key. Data were statistically analyzed by 1-way analysis of variance followed by 2-way analysis of variance (P<.05). RESULTS: Significantly higher mean torsional forces were observed with respect to Siloc (20.4 Newton decimeter [dNm]), Silicoater Classical (18.6 dNm), Silicoater MD (18.2 dNm), and Rocatec (17.0 dNm) systems compared with the mean for the untreated control group (14.6 dNm) (P<.001). The Kevloc system (10.4 dNm) demonstrated no significant difference compared with the control group (P>.001). The Kevloc system in combination with the Artglass opaquer and Photac-Fil Aplitip (0.00 dNm) core material showed no resistance against torsional forces. Significant differences were observed between hybrid core materials and microfilled composite, compomer, or resin-modified glass ionomer core materials (P<.001). CONCLUSION:Within the limitations of this study, the resistance to torsional forces for the core materials on titanium posts increased with the use of chemical surface-conditioning techniques and varied in accordance with the opaquer type. Type of core material also significantly influenced the resistance after thermocycling. 相似文献
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According to the neutral zone concept, an appropriate denture form can be molded into a physiologic tooth arrangement by using a narrow rim bar occlusion, tissue conditioner, and a direct relining technique for both intaglio and cameo surfaces by using VLC reline resin. Denture stability can be obtained with this "border molding" technique, not only for edentulous patients but also for those with oral deformities. 相似文献
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Chieko Ishikawa Yuko Shigeta Takumi Ogawa Shinya Hirai Eriko Ando Tomoko Ikawa Shintaro Kasama Keisuke Ihara Noboru Kawamura Yukihiro Mizuno Shunji Fukushima Toshio Hosoi Jun Nejima C. Ohkubo 《Journal of Indian Prosthodontic Society》2010,10(1):57-63