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1.
ESMO Open ; 7(1): 100348, 2022 02.
Article in English | MEDLINE | ID: mdl-34942439

ABSTRACT

INTRODUCTION: The albumin-bilirubin (ALBI) grade is a novel indicator of the liver function. Some studies showed that the ALBI grade was a prognostic and predictive biomarker for the efficacy of chemotherapy in cancer patients. The association between the ALBI grade and outcomes in patients with non-small-cell lung cancer (NSCLC) treated with cancer immunotherapy, however, is poorly understood. METHODS: We retrospectively enrolled 452 patients with advanced or recurrent NSCLC who received anti-programmed cell death protein 1 (PD-1)-based therapy between 2016 and 2019 at three medical centers in Japan. The ALBI score was calculated from albumin and bilirubin measured at the time of treatment initiation and was stratified into three categories, ALBI grade 1-3, with reference to previous reports. We examined the clinical impact of the ALBI grade on the outcomes of NSCLC patients receiving anti-PD-1-based therapy using Kaplan-Meier survival curve analysis with log-rank test and Cox proportional hazards regression analysis. RESULTS: The classifications of the 452 patients were as follows: grade 1, n = 158 (35.0%); grade 2, n = 271 (60.0%); and grade 3, n = 23 (5.0%). Kaplan-Meier survival curve analysis showed that the ALBI grade was significantly associated with progression-free survival and overall survival. Moreover, Cox regression analysis revealed that the ALBI grade was an independent prognostic factor for progression-free survival and overall survival. CONCLUSION: The ALBI grade was an independent prognostic factor for survival in patients with advanced or recurrent NSCLC who receive anti-PD-1-based therapy. These findings should be validated in a prospective study with a larger sample size.


Subject(s)
Albumins , Bilirubin , Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Albumins/analysis , Bilirubin/analysis , Carcinoma, Non-Small-Cell Lung/diagnosis , Carcinoma, Non-Small-Cell Lung/drug therapy , Humans , Lung Neoplasms/diagnosis , Lung Neoplasms/drug therapy , Neoplasm Recurrence, Local , Prognosis , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Prospective Studies , Retrospective Studies
4.
Oncogene ; 36(29): 4201-4211, 2017 07 20.
Article in English | MEDLINE | ID: mdl-28346423

ABSTRACT

Mps One Binder Kinase Activator (MOB)1A/1B are core components of the Hippo pathway. These proteins, which coactivate LArge Tumour Suppressor homologue kinases, are also tumour suppressors. To investigate MOB1A/B's roles in normal physiology and lung cancer, we generated doxycycline (Dox)-inducible, bronchioalveolar epithelium-specific, null mutations of MOB1A/B in mice (SPC-rtTA/(tetO)7-Cre/Mob1aflox/flox/Mob1b-/-; termed luMob1DKO mice). Most mutants (70%) receiving Dox in utero (luMob1DKO (E6.5-18.5) mice) died of hypoxia within 1 h post-birth. Their alveolar epithelial cells showed increased proliferation, impaired YAP1/TAZ-dependent differentiation and decreased surfactant protein production, all features characteristic of human respiratory distress syndrome. Intriguingly, mutant mice that received Dox postnatally (luMob1DKO (P21-41) mice) did not develop spontaneous lung adenocarcinomas, and urethane treatment-induced lung tumour formation was decreased (rather than increased). Lungs of luMob1DKO (P21-41) mice exhibited increased detachment of bronchiolar epithelial cells and decreased numbers of the bronchioalveolar stem cells thought to initiate lung adenocarcinomas. YAP1/TAZ-NKX2.1-dependent expression of collagen XVII, a key hemidesmosome component, was also reduced. Thus, a MOB1-YAP1/TAZ-NKX2.1 axis is essential for normal lung homeostasis and expression of the collagen XVII protein necessary for alveolar stem cell maintenance in the lung niche.


Subject(s)
Lung Neoplasms/metabolism , Lung Neoplasms/pathology , Acyltransferases , Adaptor Proteins, Signal Transducing/genetics , Adaptor Proteins, Signal Transducing/metabolism , Animals , Cell Adhesion/physiology , Cell Cycle Proteins , Cell Differentiation/physiology , Cell Line, Tumor , Humans , Intracellular Signaling Peptides and Proteins , Lung Neoplasms/genetics , Mice , Nuclear Proteins/genetics , Nuclear Proteins/metabolism , Phosphoproteins/genetics , Phosphoproteins/metabolism , Signal Transduction , Thyroid Nuclear Factor 1 , Trans-Activators , Transcription Factors/genetics , Transcription Factors/metabolism , YAP-Signaling Proteins
7.
J Clin Pharm Ther ; 35(1): 79-85, 2010 Feb.
Article in English | MEDLINE | ID: mdl-20175815

ABSTRACT

OBJECTIVES: The aim of this study was to identify a target range for inosin-5'-monophosphate dehydrogenase (IMPDH) activity in maintenance therapy with tacrolimus (TCL), and to apply the measurement of IMPDH activity to the therapeutic drug monitoring for mycophenolate mofetil (MMF). METHODS: Eleven patients with renal transplants and 10 healthy volunteers were investigated. All patients were treated with a combination of TCL, steroid and MMF for 2 months after transplantation, and were in stable and good condition. IMPDH activity was determined indirectly by measuring xanthosine 5'-monophophate in cell lysates supplemented with IMP and beta-nicotine adenine dinucleotide using an high-performance liquid chromatography (HPLC) method. RESULTS: The within-run reproducibility of the assay was excellent, with relative standard deviation (RSD) values of 0.41-4.08%. The mean differences between the spiked concentrations of xanthosine 5'-monophophate and their real values (mean relative errors; MREs) were within a range of 2.66-8.89%, showing good accuracy. The interday RSD values were 1.51-6.12% and MREs ranged from 2.10% to 8.89%. Cell lysates showed a 5-6 nmol/L IC(50) mycophenolic acid (MPA) concentration. TCL, cyclosporine and prednisolone did not affect IMPDH activity. The peak MPA concentration was achieved at 1 h after dosing. IMPDH activity decreased to 75% and 67% at 1 and 2 h after dosing respectively. Therefore, the inhibition rates of MPA against IMPDH activity may be adequate at 25-40% in TCL maintenance therapy. CONCLUSION: Inosin-5'-monophosphate dehydrogenase activity in cell lysates could be reliably determined by HPLC. A 25-40% inhibition of IMPDH activity may be an appropriate range for preventing rejection with MPF but this requires further validation using larger studies with harder outcomes such as rejection episodes.


Subject(s)
Drug Monitoring/methods , Enzyme Inhibitors/pharmacokinetics , IMP Dehydrogenase/blood , Immunosuppressive Agents/pharmacokinetics , Mycophenolic Acid/analogs & derivatives , Prodrugs/pharmacokinetics , Tacrolimus/pharmacokinetics , Adult , Biomarkers, Pharmacological/blood , Chromatography, High Pressure Liquid , Drug Interactions , Drug Therapy, Combination , Enzyme Inhibitors/therapeutic use , Female , Humans , IMP Dehydrogenase/antagonists & inhibitors , Immunosuppressive Agents/blood , Immunosuppressive Agents/therapeutic use , Kidney Transplantation , Kinetics , Leukocytes, Mononuclear/chemistry , Leukocytes, Mononuclear/drug effects , Leukocytes, Mononuclear/enzymology , Male , Middle Aged , Mycophenolic Acid/blood , Mycophenolic Acid/pharmacokinetics , Mycophenolic Acid/therapeutic use , Prodrugs/therapeutic use , Reproducibility of Results , Ribonucleotides/analysis , Tacrolimus/blood , Tacrolimus/therapeutic use , Xanthine , Young Adult
8.
AJNR Am J Neuroradiol ; 31(5): 827-9, 2010 May.
Article in English | MEDLINE | ID: mdl-19892818

ABSTRACT

To determine how much the radiation dose can be reduced in multidetector row CTA using a QDS, we performed CTA at various exposure settings using a vascular phantom simulating various aneurysms with superimposed bone skull structures, and postprocessed the image data with QDS. Our results demonstrated that the radiation dose of CTA can be reduced by at least 25% and the image quality for visualizing aneurysms can be preserved by applying the QDS.


Subject(s)
Angiography/methods , Body Burden , Radiation Dosage , Radiation Protection/methods , Radiographic Image Interpretation, Computer-Assisted/methods , Tomography, X-Ray Computed/methods , Algorithms , Angiography/instrumentation , Humans , Phantoms, Imaging , Reproducibility of Results , Sensitivity and Specificity , Signal Processing, Computer-Assisted , Tomography, X-Ray Computed/instrumentation
9.
AJNR Am J Neuroradiol ; 31(4): 620-5, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19942711

ABSTRACT

BACKGROUND AND PURPOSE: Optimal tube voltage and tube current settings are not well established. The purpose of our study was to investigate the image quality on 3D CT angiograms of the brain at various kilovoltage settings by evaluating the depiction of simulated intracranial lesions by using a vascular phantom. MATERIALS AND METHODS: An anthropomorphic vascular phantom with superimposed bone skull structures was designed to simulate various intracranial aneurysms with aneurysmal blebs. We performed CT angiography by using a 64-detector row CT scanner for various effective tube currents with 4 tube voltages of 80, 100, 120, and 135 kV(p). Simulated aneurysm enhancement and image noise were quantified; SNR and CNR were calculated. The depiction of the simulated aneurysms and blebs on 3D CT angiograms obtained with the volume-rendering technique was subjectively assessed. The effective dose was calculated on the basis of a CTDIw. The results of several protocols were compared by using the Student t test. RESULTS: At identical doses levels (CTDIw), the mean SNR and CNR at 100 kV(p) were significantly higher than those at 80, 120, and 135 kV(p); and the mean qualitative image score at 100 kV(p) was significantly superior to those at 80 and 135 kV(p). CONCLUSIONS: Our phantom study suggests that the tube voltage of 100 kV(p) is desirable for cerebral 3D CT angiograms, and the higher or lower kilovoltage settings may result in the degradation in diagnostic image quality.


Subject(s)
Cerebral Angiography/methods , Cone-Beam Computed Tomography/methods , Image Enhancement/methods , Image Processing, Computer-Assisted/methods , Imaging, Three-Dimensional/methods , Intracranial Aneurysm/diagnostic imaging , Phantoms, Imaging , Skull/diagnostic imaging , Tomography, Spiral Computed/methods , Artifacts , Humans , Radiometry/methods , Sensitivity and Specificity
10.
J Clin Pharm Ther ; 33(2): 159-63, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18315781

ABSTRACT

OBJECTIVES: The aim of this study was to develop a limited sampling strategy (LSS) for monitoring the use of mycophenolic acid (MPA) in maintenance therapy with tacrolimus (TCL) in renal transplant patients. METHODS: Eighteen adult patients receiving a first transplant were investigated. All patients were treated with a combination of TCL, steroid and mycophenolate mofetil (MMF). Besides the predose trough concentration (C(0)), whole blood samples were taken for measurement of the MPA concentration at 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 and 12 h for a 14-point 12-h pharmacokinetic (PK) profile. Using stepwise linear regression analysis, an abbreviated area under the concentration time curve (AUC) was calculated using all 14, and any combination of sampling points to give an estimating equation with up to three predictors. RESULTS: The equation derived from C(2), C(7) and C(12,) for AUC estimation: AUC = (2.05 x C(2)) + (8.51 xC(7)) + (2.29 x C(12)) + 4.24. was found to be optimal. Using this formula, there was an excellent correlation between the estimated 3-point AUC and AUC(0-12 h). To assess the agreement between the abbreviated methods and the full PK profile, we plotted the average AUC of the abbreviated estimates and the full PK profile. This Bland-Altman analysis indicated good agreement to within +/-2 SD and a prediction variability of 7.56 microg x h/mL. CONCLUSION: Our proposed three-sampling-point estimate of AUCs is clinically acceptable. However, the sampling times are inconvenient for outpatients, and is recommended only for monitoring MMF treatment of inpatients with suspected toxicity or at high risk of organ rejection.


Subject(s)
Immunosuppressive Agents/pharmacokinetics , Kidney Transplantation , Mycophenolic Acid/analogs & derivatives , Mycophenolic Acid/blood , Prodrugs/pharmacokinetics , Tacrolimus/therapeutic use , Adult , Area Under Curve , Drug Therapy, Combination , Female , Humans , Immunosuppressive Agents/therapeutic use , Male , Mycophenolic Acid/pharmacokinetics , Mycophenolic Acid/therapeutic use , Prodrugs/therapeutic use
11.
Kyobu Geka ; 59(10): 913-5, 2006 Sep.
Article in Japanese | MEDLINE | ID: mdl-16986687

ABSTRACT

Heartstring is a useful device. However, the device failure at the time of loading the seal into the delivery device is a troublesome issue. To avoid this problem, we invent a new method using 2 tourniquets made of 5 mm-wide woven Teflon tapes and plastic tubes. Using our method, the loading procedure became easier and more reliable.


Subject(s)
Coronary Artery Bypass/instrumentation , Tourniquets , Anastomosis, Surgical/instrumentation , Coronary Artery Bypass/methods , Humans
12.
Kidney Int ; 70(2): 391-8, 2006 Jul.
Article in English | MEDLINE | ID: mdl-16760903

ABSTRACT

Chronic hemodialysis (HD) patients increase erythrocyte susceptibility to hemolysis and impair cell survival. We explored whether electrolyte-reduced water (ERW) could palliate HD-evoked erythrocyte impairment and anemia. Forty-three patients undergoing chronic HD were enrolled and received ERW administration for 6 month. We evaluated oxidative stress in blood and plasma, erythrocyte methemoglobin (metHb)/ferricyanide reductase activity, plasma metHb, and proinflammatory cytokines in the chronic HD patients without treatment (n=15) or with vitamin C (VC)- (n=15), vitamin E (VE)-coated dialyzer (n=15), or ERW treatment (n=15) during an HD course. The patients showed marked increases (15-fold) in blood reactive oxygen species, mostly H(2)O(2), after HD without any treatment. HD resulted in decreased plasma VC, total antioxidant status, and erythrocyte metHb/ferricyanide reductase activity and increased erythrocyte levels of phosphatidylcholine hydroperoxide (PCOOH) and plasma metHb. Antioxidants treatment significantly palliated single HD course-induced oxidative stress, plasma and RBC PCOOH, and plasma metHb levels, and preserved erythrocyte metHb /ferricyanide reductase activity in an order VC>ERW>VE-coated dialyzer. However, ERW had no side effects of oxalate accumulation easily induced by VC. Six-month ERW treatment increased hematocrit and attenuated proinflammatory cytokines profile in the HD patients. In conclusion, ERW treatment administration is effective in palliating HD-evoked oxidative stress, as indicated by lipid peroxidation, hemolysis, and overexpression of proinflammatory cytokines in HD patients.


Subject(s)
Anemia/prevention & control , Erythrocytes/cytology , Hemodialysis Solutions/chemistry , Kidney Failure, Chronic/therapy , Renal Dialysis/methods , Adult , Aged , Aged, 80 and over , Anemia/blood , Anemia/etiology , Antioxidants/administration & dosage , Ascorbic Acid/administration & dosage , Biomarkers , Cell Survival , Electrolysis , Erythrocytes/metabolism , Female , Hematocrit , Hemodialysis Solutions/adverse effects , Humans , Kidney Failure, Chronic/blood , Kidney Failure, Chronic/complications , Male , Membranes, Artificial , Methemoglobin/metabolism , Middle Aged , Oxidative Stress/drug effects , Reactive Oxygen Species/metabolism , Renal Dialysis/adverse effects , Vitamin E/administration & dosage , Water/chemistry
13.
Bone Marrow Transplant ; 36(12): 1071-5, 2005 Dec.
Article in English | MEDLINE | ID: mdl-16247437

ABSTRACT

Hepatic veno-occlusive disease (VOD) is a severe complication of hematopoietic stem cell transplantation (SCT). When monitored with hand-held color Doppler ultrasonography during day -7 to +35 around SCT, reversed blood flow in the segmental branches of the portal vein was detected in nine of 56 patients who had undergone SCT. Three of nine patients had clinical evidence of VOD, but six patients did not fulfill the criteria for diagnosis of VOD initially. Two patients progressed to clinical VOD at a later date and the reversed portal flow disappeared with or without treatment for VOD in the other four patients. Monitoring for reversed portal flow with color Doppler ultrasonography may be a useful tool for the early diagnosis of VOD, and may improve prognosis by allowing early initiation of treatment.


Subject(s)
Hematopoietic Stem Cell Transplantation/adverse effects , Hematopoietic Stem Cell Transplantation/methods , Hepatic Veno-Occlusive Disease/diagnostic imaging , Hepatic Veno-Occlusive Disease/diagnosis , Hypertension, Portal/diagnosis , Portal Vein/diagnostic imaging , Ultrasonography, Doppler/methods , Adolescent , Adult , Aged , Child , Disease Progression , Female , Humans , Hypertension, Portal/diagnostic imaging , Liver Diseases/diagnosis , Liver Diseases/diagnostic imaging , Male , Middle Aged , Time Factors , Treatment Outcome , Ultrasonography/methods , Ursodeoxycholic Acid/pharmacology
14.
Pharmacopsychiatry ; 36(5): 192-6, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14571354

ABSTRACT

The aim of the present study was to seek a CYP2D6 genotypic-phenotypic discordance possibility in Japanese patients under psychotropic drug treatment where the CYP2D6 status and pharmacodynamic responses differ from those in Caucasian psychiatric patients. Ninety drug-free, healthy volunteers and 14 patients undergoing psychotropic drug treatment were phenotyped for their individual CYP2D6 activity using dextromethorphan as a probe, and then the metabolic ratio (MR) was calculated. For the genotyping, eight mutant alleles of the CYP2D6 genes were identified. Serum concentrations of two frequently co-medicated psychotropic drugs, biperiden and levomepromazine, were determined by GC/MS. Genotyping revealed no poor metabolizers (PMs) enrolled in our study. Healthy volunteers exhibited an identical phenotype-genotype concordance, whereas 7 of the 14 patients had significantly high (p < 0.05) MRs compared with genotype-matched volunteers. Three of the patients who had the extensive metabolizer (EM) genotype had extremely high MRs and were classified as phenotypic PMs. Five patients plus all of the seven high MR patients were treated with levomepromazine and/or biperiden, respectively. Their mean serum steady-state concentrations were 27.4 and 7.6 ng/ml, respectively. A CYP2D6 phenotype-genotype mismatch (phenocopying) can occur in Japanese psychiatric patients receiving clinical doses of some psychotropic drugs where the prevalence of PMs is low and the pharmacodynamic responses to those drugs are enhanced compared to Caucasian patients.


Subject(s)
Antipsychotic Agents/therapeutic use , Cytochrome P-450 CYP2D6/metabolism , Mental Disorders , Adult , Alleles , Antipsychotic Agents/blood , Female , Genotype , Humans , Male , Mental Disorders/drug therapy , Mental Disorders/ethnology , Mental Disorders/genetics , Middle Aged , Phenotype , Point Mutation/genetics
15.
Adv Space Res ; 31(7): 1833-7, 2003.
Article in English | MEDLINE | ID: mdl-14503524

ABSTRACT

In order to control the material circulation in the Closed Ecology Experiment Facilities (CEEF), it is necessary to clarify material flow in the Closed Plant Experiment Facility (CPEF) of CEEF. We tried to grow rice plants and measure the nitrogen contents in rice plant and nutrient solution in plant cultivation bed to trace the material balance in CPEF. The measurements were carried out under the condition of 750 ppm (v/v) CO2 at 26/19 degrees C in the plant cultivation room. The measurements showed the absorbed nitrogen amount in plant was less than the outflow nitrogen amount from nutrient solution. This difference between absorbed and outflow quantity reached to 17%.


Subject(s)
Ecological Systems, Closed , Life Support Systems , Nitrogen/analysis , Oryza/metabolism , Ammonia/chemical synthesis , Biomass , Culture Media/chemistry , Facility Design and Construction , Fertilizers , Moon , Nitrates/chemical synthesis , Nitrogen/chemistry , Nitrogen/metabolism , Oryza/chemistry , Oryza/growth & development
16.
J Clin Pharm Ther ; 28(1): 17-22, 2003 Feb.
Article in English | MEDLINE | ID: mdl-12605614

ABSTRACT

OBJECTIVE: To develop a simple analytical method for monitoring serum and urine concentrations of mycophenolic acid (MPA), an active metabolic constituent of the immunosuppressive pro-drug mycophenolate mofetil, and its glucuronide. METHODS: Serum samples were prepared by solid-phase extraction (SPE), while urine samples were simply diluted with water. Serum was added to an SPE cartridge, then washed twice with 5% methanol solution. The analytes were eluted with methanol containing benzoic acid as internal standard for mycophenolic acid glucuronide (MPAG). The resultant eluate was directly injected into a high-performance liquid chromatograph (HPLC) to determine MPAG. For the assay of MPA, the remaining eluate was dried under nitrogen and resolved in a mixture of acetonitrile and 20 mM phosphate buffer (pH 3.0). RESULTS: The present methods were reproducible and accurate based on the intra- and inter-assay, and had detection limits of 0.225 microg/mL for MPA and 9.0 microg/mL for MPAG. The present methods enabled us to monitor the time course of changes in the concentrations of MPA and MPAG in serum and urine in a patient with a renal transplant during 12 h after ingestion of mycophenolate mofetil. CONCLUSION: The HPLC method described should be useful for the routine monitoring of serum and urine concentrations of MPA and MPAG during immunosuppressive medication for renal transplantation.


Subject(s)
Immunosuppressive Agents/blood , Immunosuppressive Agents/urine , Mycophenolic Acid/analogs & derivatives , Mycophenolic Acid/blood , Mycophenolic Acid/urine , Administration, Oral , Chromatography, High Pressure Liquid/methods , Drug Monitoring , Glucuronates/blood , Glucuronates/urine , Glucuronides , Humans , Kidney Transplantation , Mycophenolic Acid/pharmacokinetics , Prodrugs/pharmacokinetics , Reproducibility of Results , Sensitivity and Specificity
17.
Article in English | MEDLINE | ID: mdl-12383476

ABSTRACT

A column-switching high-performance liquid chromatographic analysis was established to monitor the serum concentration of mycophenolic acid, the active metabolite from mycophenolate mofetil administered for the prophylaxis of acute organ rejection in renal transplantation. The system consisted of two pumps for solvent delivery, a column-switching valve, a precolumn, and a reversed-phase analytical column. The present method enabled us to determine MPA by injecting serum samples directly into HPLC without any pretreatment. The mobile phases with different amounts of organic solvent were delivered to the precolumn and analytical column by separate lines, and samples were applied to the precolumn. The column switching valves were switched automatically following the processes for the elimination of protein and the drug analysis. The peak heights of MPA were linearly related to the concentrations (r=0.999) in the range of 0.1-20 micro g/ml, and the limit of quantification was 0.1 micro g/ml (S/N ratio=3). This method was accurate and reproducible on the basis of the results of recovery (94.0-98.0%) and small coefficient of variations of intra and inter-assay (less than 8.3%).


Subject(s)
Chromatography, High Pressure Liquid/methods , Mycophenolic Acid/blood , Chromatography, High Pressure Liquid/instrumentation , Humans , Reproducibility of Results , Sensitivity and Specificity
18.
J Mater Sci Mater Med ; 13(2): 169-73, 2002 Feb.
Article in English | MEDLINE | ID: mdl-15348639

ABSTRACT

The purpose of this research was to investigate the possible orthodontic application of the hollow super-elastic Ti-Ni alloy wire, which was thought not only to deliver much lower and more continuous orthodontic force than conventional Ti-Ni wires, but also be able to be applied as a compound wire when combined with another wire. The examinations of bending properties were performed by the three-point bending test. The following results were obtained. 1. The hollow wire had lower load in the super-elastic range, smaller load-deflection rate and stress hysteresis in comparison with the conventional wire of the same diameter. 2. The load of the hollow wire was controllable by heat treatment. The stress hysteresis was further decreased by a two-step heat treatment. 3. The compound wire formed by inserting other types of wires into the hollow core exhibited changes in various bending properties such as increased load or load-deflection rate, according to the types and diameters of the inserted wire. The hollow wire delivers much lighter and more continuous orthodontic force, and, through heat treatment or deployment as a compound wire, it is possible to alter various bending properties. Therefore, this hollow wire was evaluated as a promising candidate for orthodontic application.

19.
J Mater Sci Mater Med ; 13(2): 197-202, 2002 Feb.
Article in English | MEDLINE | ID: mdl-15348643

ABSTRACT

The purpose of this research was to devise a method for transforming the cross-section of the hollow super-elastic Ti-Ni alloy round wire and to examine the changes in its bending properties for clinical orthodontic application. The specimen wires were pressed with the use of heated pliers to transform the cross-sectional shape. As a result, transformation of the wire cross-section with super-elasticity was possible. As a verified by cantilever test and three-point bending test of the transformed specimens, a two-dimensional orthodontic force, which was different in each bending direction, was obtained. The hollow wire showed considerably high load level in the long axis along with markedly low load level in the short axis, which was mainly caused by the change in the moment of inertia by transforming the cross-section. It was revealed that, by transforming the wire cross-section of the hollow super-elastic Ti-Ni alloy round wires, anisotropic orthodontic force in bending properties could be obtained with super-elasticity.

20.
Eur J Clin Pharmacol ; 57(6-7): 485-92, 2001 Sep.
Article in English | MEDLINE | ID: mdl-11699613

ABSTRACT

BACKGROUND: Little is known about differences in the disposition kinetics and pharmacological effects on gastrin levels between lansoprazole and rabeprazole given in a repeated dosing scheme with respect to the polymorphic CYP2C19. AIM: To provide preliminary information that should be considered when prescribing proton-pump inhibitors (PPIs) for the treatment of acid-related diseases with reference to the CYP2C/9 genotypic status. METHODS: Helicobacter pylori-negative healthy volunteers were divided into the following three groups (n = 5 each) on the basis of genotyping for CYP2C19: homozygous (hmEMs) and heterozygous extensive metabolizers (htEMs), and poor metabolizers (PMs). All received once-daily 30-mg doses of lansoprazole or 10-mg doses of rabeprazole during an 8-day course in a crossover manner. RESULTS: The relative values for the area under the serum concentration-time curve (AUC) of lansoprazole and rabeprazole in the hmEMs, htEMs, and PMs after the final doses were 1:1.7:3.9 and 1:1.7:3.8, respectively. The relative AUCs of gastrin in the hmEMs, htEMs, and PMs were 1.6:2.6:3.1 for lansoprazole and 1.6:2.6:2.9 for rabeprazole, respectively. CONCLUSION: The disposition kinetic behavior of the two PPIs is co-segregated with CYP2C19. The magnitude of CYP2C19-dependent drug availability in the systemic circulation and resulting gastrin response appears to be fairly similar between the two drugs within the same CYP2C19 genotypic groups after a multiple-dosing regimen.


Subject(s)
Anti-Ulcer Agents/pharmacokinetics , Aryl Hydrocarbon Hydroxylases , Benzimidazoles/pharmacokinetics , Cytochrome P-450 Enzyme System/metabolism , Gastrins/blood , Mixed Function Oxygenases/metabolism , Omeprazole/analogs & derivatives , Omeprazole/pharmacokinetics , 2-Pyridinylmethylsulfinylbenzimidazoles , Adenosine Triphosphatases/antagonists & inhibitors , Adult , Anti-Ulcer Agents/chemistry , Anti-Ulcer Agents/metabolism , Area Under Curve , Benzimidazoles/chemistry , Cross-Over Studies , Cytochrome P-450 CYP2C19 , Cytochrome P-450 Enzyme System/genetics , Female , Genotype , Humans , Lansoprazole , Male , Mixed Function Oxygenases/genetics , Omeprazole/chemistry , Omeprazole/metabolism , Polymorphism, Genetic , Proton Pump Inhibitors , Proton-Translocating ATPases/antagonists & inhibitors , Rabeprazole
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