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1.
Anat Histol Embryol ; 45(4): 285-90, 2016 Aug.
Article in English | MEDLINE | ID: mdl-26268523

ABSTRACT

In mammals, a pair of ejaculatory ducts exists in the urethra at the seminal colliculus. The detailed anatomical structures of the distal end of the ejaculatory ducts of Sprague-Dawley rats were investigated by the computer-assisted three-dimensional reconstruction analysis using light-microscopic serial sections. A three-dimensional reconstruction revealed that in adult rats, the ejaculatory sinus pair consists of two parts: the cranial section - a compartment region composed of a fusion of the ampullary gland duct and the seminal vesicle duct, and the caudal section - a grooved region composed of a long slitlike ejaculatory ostium that extends into the urethra on both sides of the seminal colliculus. But the sphincter structure was not observed. The long axis of the compartment region was approximately 58 µm in length, and that of the groove region was approximately 495 µm. Although many epithelial glands ducts were distributed throughout the ejaculatory sinuses, the prostate and coagulation gland ducts did not open in these sinuses. The urethra was composed of transitional epithelium, while the ejaculatory sinuses were composed of single to stratified cuboidal epithelium. The ejaculatory ducts continued to the ejaculatory ostium in male adult Sprague-Dawley rat were composed of the seminal vesicle ducts received the ampullary gland ducts.


Subject(s)
Ejaculatory Ducts/anatomy & histology , Imaging, Three-Dimensional/methods , Seminal Vesicles/anatomy & histology , Urethra/anatomy & histology , Animals , Male , Rats , Rats, Sprague-Dawley
3.
J Periodontal Res ; 47(5): 593-8, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22376058

ABSTRACT

BACKGROUND AND OBJECTIVE: Reactive oxygen species and free radicals are involved in the pathogenesis of periodontal disease. Previous studies have shown that the stage of the menstrual cycle is associated with the levels of gingival inflammation and discomfort. This study examined changes in salivary antioxidant activities, clinical parameters and bacterial levels during the menstrual cycle. MATERIAL AND METHODS: The study group consisted of 16 women with periodontitis and 12 healthy women. Clinical and bacterial measurements were performed for all subjects during the ovulatory and follicular phases. RESULTS: Salivary antioxidant activity during the ovulatory phase was significantly lower than during the follicular phase in the women with periodontitis. The antioxidant activity in all subjects during the ovulatory phase was negatively correlated with Prevotella intermedia (r = -0.430; p = 0.023) and total bacterial counts (r = -0.496; p = 0.007); however, these correlations were not significant for subjects in the follicular phase. CONCLUSION: This study showed that salivary antioxidant capacity decreased, while bleeding on probing and P. intermedia increased, over the course of the menstrual cycle in women with periodontitis. Antioxidant capacity could be involved in the pathogenesis of periodontitis.


Subject(s)
Antioxidants/metabolism , Menstrual Cycle/metabolism , Saliva/metabolism , Adult , Bacteria/isolation & purification , Bacterial Load , Dental Plaque Index , Female , Follicular Phase/metabolism , Free Radicals/metabolism , Gingival Hemorrhage/metabolism , Gingival Hemorrhage/microbiology , Humans , Ovulation/metabolism , Periodontal Pocket/metabolism , Periodontal Pocket/microbiology , Periodontitis/metabolism , Periodontitis/microbiology , Porphyromonas gingivalis/isolation & purification , Prevotella intermedia/isolation & purification , Reactive Oxygen Species/metabolism , Saliva/microbiology , Secretory Rate/physiology , Young Adult
4.
J Periodontal Res ; 45(5): 681-7, 2010 Oct.
Article in English | MEDLINE | ID: mdl-20572919

ABSTRACT

BACKGROUND AND OBJECTIVE: Sex hormones have been suggested to be important modifying factors that may influence the pathogenesis of periodontal disease. This study examined changes in volatile sulfur compounds (VSC) levels, clinical parameters and bacterial levels during the menstrual cycle. MATERIAL AND METHODS: The study group consisted of 10 female subjects with periodontitis and 12 periodontally healthy female subjects. Clinical and bacterial measurements were performed for all subjects during the ovulation and follicular phases of the menstrual cycle. RESULTS: Bleeding on probing (BOP) was significantly increased in the ovulation phase in periodontitis subjects but not in healthy subjects. The VSC levels in subjects with periodontitis increased 2.2-fold in the ovulation phase compared with the follicular phase. In the ovulation phase, VSC levels and BOP were significantly higher in subjects with periodontitis than in healthy subjects. The number, and salivary levels, of Prevotella intermedia in subjects with periodontitis were significantly higher in the ovulation phase than in the follicular phase. CONCLUSION: The present study indicated changes in VSC, BOP and P. intermedia during the menstrual cycles of women with periodontitis.


Subject(s)
Halitosis/metabolism , Menstrual Cycle/metabolism , Periodontitis/metabolism , Adult , Breath Tests , Case-Control Studies , DNA, Bacterial/analysis , Female , Halitosis/complications , Humans , Periodontal Index , Periodontitis/complications , Periodontitis/microbiology , Porphyromonas gingivalis/isolation & purification , Prevotella intermedia/isolation & purification , Saliva/microbiology , Statistics, Nonparametric , Sulfur Compounds/analysis , Young Adult
5.
Nanotechnology ; 21(13): 134013, 2010 Apr 02.
Article in English | MEDLINE | ID: mdl-20208119

ABSTRACT

We present a comparative study of the influence of the thickness on the strain behavior upon nanoscale patterning of ultrathin strained Si layers directly on oxide. The strained layers were grown on a SiGe virtual substrate and transferred onto a SiO(2)/Si substrate using wafer bonding and hydrogen ion induced exfoliation. The post-patterning strain was evaluated using UV micro-Raman spectroscopy for thin (20 nm) and thick (60 nm) nanostructures with lateral dimensions in the range of 80-400 nm. We found that about 40-50% of the initial strain is maintained in the 20 nm thick nanostructures, whereas this fraction drops significantly to approximately 2-20% for the 60 nm thick ones. This phenomenon of free surface induced relaxation is described using detailed three-dimensional finite element simulations. The simulated strain 3D maps confirm the limited relaxation in thin nanostructures. This result has direct implications for the fabrication and manipulation of strained Si nanodevices.

6.
J Microsc ; 229(Pt 2): 217-22, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18304075

ABSTRACT

Tip-enhanced Raman imaging of strained silicon reveals the property of nanoscale stress imposed on the lattice. Our approach relies on the highly localized excitation provided by a metallized tip. Surface sensitive detections in nanoscale are realized by a reflection-mode configuration combined with 442-nm excitation and a silver-coated silicon nitride tip. The background signals from an underlying silicon germanium layer and a tip are well suppressed. The quantitative stress analysis is made on the basis of the Raman shift of the Si-Si phonon mode. We succeeded in visualizing the localized stress with a spatial resolution down to 25 nm whereas a conventional micro Raman technique provides only a uniform image because of the averaging effect within a diffraction-limited focused spot.

7.
J Orthop Surg (Hong Kong) ; 12(2): 210-5, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15621909

ABSTRACT

PURPOSE: To assess the mechanism of injury of anterior cruciate ligaments, surgical results, and radiographic findings among patients with bilateral knee injuries, and to compare these features with those of patients sustaining unilateral injuries. METHODS: From 1977 to 1988, among 458 patients with injury of anterior cruciate ligament operated in our hospital, 11 were of bilateral injury, in whom 10 could be followed up. A laxity score was calculated to evaluate laxity of 7 joints. A notch width index was measured to show the narrowing of femoral notch. RESULTS: The mean follow-up duration was 3 years 3 months. All 10 patients with bilateral injury of anterior cruciate ligaments were female, and 90% had non-contact injuries. The mean (standard deviation) laxity score was significantly higher in the bilateral injury group than in the unilateral injury group (3.3 [1.4] versus 2.2 [1.4] points; p<0.05). The mean notch width index was significantly lower in the bilateral injury group than in the healthy group (0.278 [0.025] versus 0.294 [0.031]; p<0.05). The mean age at the time of the first injuries was significantly lower among the bilateral injury group than among the unilateral injury group (16.6 [2.1] years versus 19.8 [6.1]; p<0.05). The level of return to full sporting activities was low in the bilateral group. CONCLUSION: These results suggest that several factors are involved in the occurrence of the anterior cruciate injuries. Besides being younger at the time of the first injury, patients in bilateral injury group had higher mean laxity score and lower mean notch width index than unilateral injury group. Most of the injuries in bilateral group were of non-contact type.


Subject(s)
Anterior Cruciate Ligament Injuries , Athletic Injuries/surgery , Knee Injuries/surgery , Adolescent , Adult , Anterior Cruciate Ligament/surgery , Child , Female , Follow-Up Studies , Humans , Male , Middle Aged , Retrospective Studies , Risk Factors , Treatment Outcome
8.
Biol Pharm Bull ; 24(1): 19-26, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11201240

ABSTRACT

Mouse thioglycollate-induced peritoneal macrophages effectively, in the absence of serum, recognized mouse polymorphonuclear leukocytes (PMNs) mildly oxidized with diamide, superoxide (hypoxanthine/xanthine oxidase) or t-butyhydroperoxide, or modified with N-ethylmaleimide (NEM). The recognition reached a maximum when PMNs were treated wtih each of the reagents at relatively low concentrations, and the recognition was decreased on treatment with reagents at higher concentrations. Glutathione depletion in the diamide-oxidized PMNs may cause enhanced adhesion to macrophages. Sialylated sugar chains attached to a peptide chain in glycophorin A and sialylated poly-N-acetyllactosaminyl sugar chains in lactoferrin and band 3 glycoprotein effectively inhibited the increased adhesion of the diamide-oxidized PMNs. Enzymatic removal of sialyl residues and the degradation of poly-N-acetyllactosaminyl sugar chains by pretreatment of PMNs with neuraminidase or endo-beta-galactosidase, respectively, lost their increasing ability for macrophage adhesion after oxidation with diamide, superoxide or t-butylhydroperoxide. Clustered sialylated poly-N-acetyllactosaminyl sugar chains on the cell surface may be involved in the increased adhesion of the oxidized PMNs to macrophages.


Subject(s)
Carbohydrate Metabolism , Cell Adhesion , Macrophages/cytology , Neutrophils/cytology , Animals , Binding Sites , Cell Membrane/metabolism , Glutathione/metabolism , Humans , Macrophages/metabolism , Mice , Neutrophils/metabolism , Oxidation-Reduction
9.
Sangyo Eiseigaku Zasshi ; 41(4): 88-94, 1999 Jul.
Article in Japanese | MEDLINE | ID: mdl-10481859

ABSTRACT

The effect of occupational sulfuric acid exposure and other factors on teeth was explored in a cross-sectional study with blind dental examinations. Among 350 male workers in a copper-smelter in Japan, 28 had mild dental erosion with silky-glazed opaque appearance of the enamel and/or shallow concavities on the enamel. While opaqueness was observed in 20 and concavities found in 11 workers, only 3 had both signs, suggesting that the concave lesions were often accompanied with enough remineralization to keep the dental surface gloss, possibly due to acid exposure at a low level. The cases had a history of working in an electrolytic refining plant (36%), significantly more than in the non-cases (14%, p < 0.05). Some significant differences were found between the cases and the non-cases: the cases were older, had less dental plaque, less gingivitis, and more frequent toothbrushing habits. No significant differences were observed in possibly related dietary habits such as several types of acidic drinks. It was concluded that the present cases with dental erosion were most probably associated with occupational acid exposure. The risk ratio of cross-sectional prevalence of dental erosion for those with a history of electrolytic refining plant work was 3.0 (95% CI: 1.3-6.7) compared with those without a history of acid exposure. Whether the present work environment can still develop new cases of dental erosion remains to be studied.


Subject(s)
Metallurgy , Occupational Diseases/chemically induced , Occupational Diseases/epidemiology , Occupational Exposure , Sulfuric Acids/adverse effects , Tooth Erosion/chemically induced , Tooth Erosion/epidemiology , Adult , Aged , Humans , Japan/epidemiology , Male , Middle Aged , Prevalence
10.
Article in English | MEDLINE | ID: mdl-10225622

ABSTRACT

OBJECTIVE: The purpose of this study was to investigate the reactions of bone tissue after the placement of implants into the tibiae of osteopenic model rats. STUDY DESIGN: Commercially pure titanium screw implants were placed in the bilateral proximal tibial metaphyses 168 days after ovariectomy had been performed on 12-week-old female Wistar rats. For control purposes, implants were similarly placed in sham-ovariectomy rats. The healing process was examined histologically by means of undecalcified sections at various intervals from 7 to 168 days after implantation. Through use of an automated imaging analytic system, changes in relative bone mass and implant-bone contact were histomorphometrically evaluated. RESULTS: In the cortical bone area, only a slight difference in bone contact was noted with the implant until 28 days after implantation. However, ovariectomy significantly affected bone contact at 56 days after implantation. The rate of bone contact in the cancellous bone area and the relative bone mass around the implant were significantly lower in the test group than in the control group. CONCLUSIONS: It is considered that a decrease in bone mass causes a reduction in the contact area between implant and bone and may also cause a reduction in the supporting ability of the implant because of thinning of the surrounding bone tissue.


Subject(s)
Implants, Experimental , Osseointegration/physiology , Osteoporosis, Postmenopausal/physiopathology , Ovary/physiology , Animals , Body Weight , Bone Density , Estrogens/deficiency , Female , Humans , Male , Ovariectomy , Rats , Rats, Wistar , Tibia
11.
J Chromatogr B Biomed Sci Appl ; 726(1-2): 225-36, 1999 Apr 16.
Article in English | MEDLINE | ID: mdl-10348190

ABSTRACT

A complete two-dimensional separation technique for the determination of acidic compounds in plasma was developed by using column-switching reversed-phase liquid chromatography. This technique was based on solute peak enrichment at the top of the second column during heart-cutting and an ion-pair chromatographic separation in the second column using tetrabutylammonium ion, where different separation modes in the first and second columns and solute peak enrichment at the top of the second column during heart-cutting were achieved coincidentally. Retention behaviors of two solutes, zidovudine-beta-D-glucuronide (AZT-beta-D-Gluc) and probenecid, in the first and second column and solute peak enrichment at the top of the second column were investigated for establishment of the system. Different retention behaviors of the solutes in the first and second column, which were evaluated by changes in capacity factor versus acetonitrile concentration in the mobile phases, and peak enrichment could be accomplished by using ion-pair chromatography in the second column. System suitability was confirmed by assessing the number of theoretical plates (N) of the second column for the solutes after heart-cutting. The N values in the second column after column switching were almost same as those in the case that the solutes were directly injected onto the second column. These results indicate that complete two-dimensional separation should be achieved by using this system. Furthermore, this technique was applied to method development for the determination of AZT-beta-D-Gluc and probenecid in rat plasma. The peaks of each analyte in the plasma extract obtained by deproteinization were well separated from those of endogenous substances, and easy determination of the analytes could be accomplished at the ng/ml level only by changing the acetonitrile concentration in the mobile phases.


Subject(s)
Acids/blood , Chromatography, Liquid/methods , Animals , Calibration , Chromatography, Liquid/instrumentation , Probenecid/blood , Rats , Reproducibility of Results , Zidovudine/analogs & derivatives , Zidovudine/blood
12.
Article in English | MEDLINE | ID: mdl-10052367

ABSTRACT

OBJECTIVE: The purpose of this study was to investigate bone reaction after implantation in an estrogen-deficient state by examining the changes in bone reactions within tissue surrounding implants in ovariectomized rats. STUDY DESIGN: Ninety-six 12-week-old female Wistar rats were used in the study; they were divided into 2 groups, an ovariectomized group and a sham-operated group. Hydroxyapatite-coated implants were placed in the proximal metaphyses of the tibiae 21 days after surgery. The tibiae were examined histologically by undecalcified sections at various intervals from 7 to 168 days after surgery. RESULTS: In the cortical bone area of the ovariectomized rats, the procedure did not induce any apparent changes in bone volume around the implant or in bone contact with the implant in comparison with the sham-operated rats. In contrast, both bone volume around the implant and contact of the implant with new bone were significantly decreased in the cancellous bone area in the ovariectomized rats in comparison with the sham-operated rats. CONCLUSIONS: Ovariectomy did not seriously affect bone healing after the placement of implants in cortical bone areas, but it reduced the bone contact ratio and the bone in the cancellous bone area.


Subject(s)
Coated Materials, Biocompatible , Estrogens/deficiency , Implants, Experimental , Osseointegration/physiology , Acid Phosphatase/metabolism , Animals , Bone Density , Bone and Bones/physiology , Durapatite , Estrogens/physiology , Female , Isoenzymes/metabolism , Osteoclasts/enzymology , Osteogenesis/physiology , Ovariectomy , Rats , Rats, Wistar , Statistics, Nonparametric , Tartrate-Resistant Acid Phosphatase , Wound Healing/physiology
13.
J Chromatogr B Biomed Sci Appl ; 712(1-2): 161-7, 1998 Aug 07.
Article in English | MEDLINE | ID: mdl-9698238

ABSTRACT

A double column-switching high-performance liquid chromatographic (HPLC) method for the determination of concentrations for TAK-603 (T) and its metabolites, T-72258 (M-I) and T-72294 (M-III), in human serum was developed. The analytes were extracted with ethyl acetate from human serum samples treated with triethylamine and injected into the HPLC system. Separation of the analytes was performed on the HPLC system with double column-switching technique. The mobile phases A and B for the first column and the mobile phase C for the second column used were a mixture of methanol-10 mM aqueous ammonium acetate solution (1:1, v/v), methanol and a mixture of methanol-10 mM aqueous ammonium acetate solution (11:9, v/v), respectively. The eluate was monitored with a UV detector at a wavelength of 253 nm. The work-up procedure was reproducible and more than 90% of the analytes could be recovered from human serum. The lower limits of quantitation were all 1 ng/ml for the analytes when 0.5 ml of human serum was used. Standard curves were linear with a correlation coefficient (R) of more than 0.999 in the range of 1-500 ng/ml for T, M-I and M-III in human serum. The intra- and inter-day precision of the method for the various analytes were below 4.8%. The accuracy was good with the deviations between spiked and calculated concentrations of the analytes being within 11.0%. The method was successfully applied to analyze serum samples after an oral administration of T to healthy male volunteers.


Subject(s)
Antirheumatic Agents/blood , Quinolines/blood , Triazoles/blood , Administration, Oral , Antirheumatic Agents/administration & dosage , Antirheumatic Agents/pharmacokinetics , Chromatography, High Pressure Liquid , Drug Stability , Humans , Male , Quinolines/administration & dosage , Quinolines/pharmacokinetics , Reproducibility of Results , Sensitivity and Specificity , Spectrophotometry, Ultraviolet , Triazoles/administration & dosage , Triazoles/pharmacokinetics
14.
Arzneimittelforschung ; 48(7): 750-7, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9706376

ABSTRACT

The disposition of ethyl 4-(3,4-dimethoxyphenyl)-6,7-dimethoxy-2-(1,2,4- triazol-1-ylmethyl) quinoline-3-carboxylate (CAS 158146-85-1, TAK-603) after single oral dosing of 14C-labeled TAK-603 ([14C]TAK-603) at 10 mg/kg to rats and dogs was studied. In rats, the concentration of unchanged drug in plasma reached a peak (Cmax, 0.31 microgram/ml) 2 h (Tmax) after dosing of TAK-603 and declined biphasically with apparent half-lives (t 1/2 alpha, t 1/2 beta) of 1.5 and 3.6 h. In dogs, Tmax, Cmax, T 1/2 alpha, and t 1/2 beta were 1.7 h, 0.36 microgram/ml, 1.2, and 10.8 h, respectively. [14C]TAK-603 dosed orally was absorbed quantitatively in rats, while the extent of absorption in dogs was 54%. The bioavailability of TAK-603 was 53% and 42% in rats and dogs, respectively. In rats, 14C was distributed widely in various tissues, with relatively high concentrations in the liver, adrenal gland, and gut. The elimination of 14C from the thyroid was slower than that from other tissues. Unchanged TAK-603 and its pharmacologically active metabolite, M-I, which has the same potency as TAK-603, were distributed in articular soft tissues and synovial fluids, as target tissues, in rats and dogs, respectively. After oral administration of [14C]TAK-603, most of the 14C dosed was excreted within 48 h in rats and within 96 h in dogs. In both animals, a greater amount of the 14C dosed was excreted in feces than in urine. In biliary duct cannulated rats given [14C]TAK-603 intraduodenally, 69% of the dose was excreted in bile, and biliary 14C in part underwent enterohepatic circulation.


Subject(s)
Antirheumatic Agents/pharmacokinetics , Quinolines/pharmacokinetics , Triazoles/pharmacokinetics , Administration, Oral , Animals , Bile/metabolism , Blood Cells/metabolism , Blood Proteins/metabolism , Cartilage, Articular/metabolism , Dogs , Injections, Intravenous , Joints/metabolism , Male , Protein Binding , Rats , Rats, Wistar , Species Specificity , Synovial Fluid/metabolism , Tissue Distribution
15.
Arzneimittelforschung ; 47(1): 22-8, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9037439

ABSTRACT

Metabolic studies of pioglitazone (CAS 105355-27-9, AD-4833), a new agent, in rats and dogs using liquid chromatography/tandem mass spectrometry and 1H-nuclear magnetic resonance led to characterization of the following metabolites; the parent compound, (+/-)-5-(p-hydroxybenzyl)-2-4-thiazolidinedione (M-I), (+/-)-5-[p-[2-(5-ethyl-2-pyridyl)-2-hydroxyethoxy]benzyl] -2,4-thiazolidinedione (M-II), (+/-)- 5-[p-[2-(5-acetyl-2-pyridyl)ethoxy]benzyl]2,4-thiazolidinedione (M-III), (+/-)-5-[p-[2-[5-(1-hydroxyethyl)-2- pyridyl]ethoxy]benzyl]-2,4-thiazolidinedione (M-IV), (+/-)-5-[p-[2-(5- carboxymethyl-2-pyridyl)ethoxy]- benzyl]-2,4-thiazolidinedione (M-V), and (+/-)-5-[p-[2-(5-carboxy-2- pyridyl)ethoxy]benzyl]-2,4-thiazolidinedione (M-VI). Pioglitazone is considered to be metabolized by cleavage of aliphatic C-O bond to lead to M-I, hydroxylation of aliphatic methylene groups to form M-II and M-IV, oxidation of M-IV to give M-III, oxidation of the ethyl group to form M-V, and oxidative loss of the terminal carbon to lead to M-IV. Furthermore, part of metabolites exist as conjugated form. Among the conjugates, M-IV conjugated with sulfuric acid and M-V conjugated with taurine were identified.


Subject(s)
Hypoglycemic Agents/pharmacokinetics , Thiazoles/pharmacokinetics , Thiazolidinediones , Administration, Oral , Animals , Bile/metabolism , Biotransformation , Chromatography, Liquid , Dogs , Intubation, Gastrointestinal , Magnetic Resonance Spectroscopy , Male , Mass Spectrometry , Pioglitazone , Rats , Rats, Sprague-Dawley
16.
Arzneimittelforschung ; 47(1): 29-35, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9037440

ABSTRACT

The disposition of pioglitazone (CAS 105355-27-9, AD-4833) was studied after oral administration to rats, dogs, and monkeys using 14C-labeled drug. After oral dosing, pioglitazone was well absorbed from the gastrointestinal tract at an extent of 96, 95, and 90% in rats, dogs, and monkeys, respectively. In rats, the concentration of pioglitazone in plasma reached a peak (Cmax 0.71 micrograms/ml) at 4 h (tmax) after dosing and declined with a half-life (t1/2) of 2.6 h. In dogs, tmax, Cmax and t1/2 were 0.5 h 0.32 micrograms/ml and 2.1 h, and those for monkeys were 4.3 h, 0.43 micrograms/ml and 5.3 h, respectively. The drug was metabolized mainly to M-I to M-VI including the pharmacologically active metabolites (M-II, III and IV). The pharmacologically active compounds (total of the unchanged compound and the above three active metabolites) accounted for 87, 71, and 73% of the radioactivity in plasma of rats, dogs and monkeys, respectively. The radioactivity was widely distributed in tissues after oral administration to rats, and decreased to the very low concentration within 24 to 72 h after dosing. Radioactivity dose was almost completely excreted in urine and feces.


Subject(s)
Hypoglycemic Agents/pharmacokinetics , Thiazoles/pharmacokinetics , Thiazolidinediones , Administration, Oral , Animals , Area Under Curve , Biotransformation , Dogs , Half-Life , Hypoglycemic Agents/administration & dosage , In Vitro Techniques , Injections, Intravenous , Intestinal Absorption , Macaca fascicularis , Male , Pioglitazone , Rats , Rats, Sprague-Dawley , Thiazoles/administration & dosage , Tissue Distribution
17.
J Chromatogr B Biomed Sci Appl ; 704(1-2): 325-31, 1997 Dec 19.
Article in English | MEDLINE | ID: mdl-9518166

ABSTRACT

A high-performance liquid chromatographic (HPLC) method was developed for the simultaneous determination of seratrodast, a new antiasthmatic drug, and its metabolites (M-I to M-III) in human serum and urine. The method for serum and urine with and without enzymatic hydrolysis using beta-glucuronidase involved liquid-liquid extraction and chemical oxidation with iron(III) chloride. The compounds in the extract were analyzed using HPLC with UV detection at 266 nm. The detection limits of seratrodast, M-I, M-II and M-III in serum and urine were 5-10 and 5-20 ng/ml, respectively, and those of deconjugated compounds in urine were 10-50 ng/ml. The method was applicable for human serum and urine from clinical trials.


Subject(s)
Anti-Asthmatic Agents , Benzoquinones/blood , Benzoquinones/urine , Chromatography, High Pressure Liquid/methods , Heptanoic Acids/blood , Heptanoic Acids/urine , Benzoquinones/metabolism , Chlorides , Ferric Compounds , Glucuronidase , Heptanoic Acids/metabolism , Humans , Hydrolysis , Microchemistry , Oxidation-Reduction , Prostaglandin Antagonists , Quality Control , Sensitivity and Specificity
18.
J Mass Spectrom ; 31(8): 873-8, 1996 Aug.
Article in English | MEDLINE | ID: mdl-8799313

ABSTRACT

Combined liquid chromatography and electrospray mass spectrometry (LC/ESI-MS) and tandem mass spectrometry (MS/MS) were used for the characterization of the conjugated metabolites (glucuronides) of a new angiotensin II receptor antagonist, candesartan cilexetil (TCV-116; (+/-)-1-(cyclohexyloxycarbonyloxy)ethyl 2-ethoxy-1-¿[2'-(1H-tetrazol-5-yl)biphenyl- 4-yl]methyl¿-1H-benzimidazole-7-carboxylate) in the plasma and bile of rats given the drug. The glucuronides of the active component, M-I (candesartan), in rat plasma and bile were positional isomers with respect to the binding site of glucuronic acid. The site of glucuronidation in M-I was not directly identified by mass spectrometry. However, the structure of the isomers could be elucidated by the MS/MS analysis of dimethylated glucuronides prepared by the reaction of glucuronide isomers with diazomethane: N-glucuronide of M-I (M-I-NG) in the plasma and acyl glucuronide (M-I-AG) in the bile. The results obtained in this study indicated that LC/ESI-MS/MS analysis provides the detailed structure of conjugated metabolite by simple chemical derivatization.


Subject(s)
Angiotensin II/metabolism , Angiotensin Receptor Antagonists , Benzimidazoles/analysis , Biphenyl Compounds/analysis , Tetrazoles , Animals , Benzimidazoles/chemistry , Benzimidazoles/pharmacokinetics , Bile/chemistry , Biotransformation , Biphenyl Compounds/chemistry , Biphenyl Compounds/pharmacokinetics , Chromatography, Liquid , Glucuronates/analysis , Male , Mass Spectrometry , Methylation , Rats , Rats, Wistar
19.
J Chromatogr B Biomed Appl ; 682(2): 343-8, 1996 Jul 12.
Article in English | MEDLINE | ID: mdl-8844429

ABSTRACT

An on-line solid-phase extraction technique based on column switching (heart-cutting) was developed for direct injection analysis of furosemide in human serum. In order to minimize the influence of deterioration in pre-treatment column efficiency, which was caused by protein precipitation with repeated injections of serum, furosemide was completely enriched at the top of the analytical column by ion-pair formation with tetra-n-butylammonium ion during heart-cutting. The robustness of the established on-line solid-phase extraction system was confirmed under routine conditions. As a result, almost comparable chromatograms could be obtained even though 50 repeated injections of a 100-microliter volume of serum were carried out using one pre-treatment column. The linearity of the calibration curves was demonstrated by the correlation coefficient which was greater than 0.99999 (5-1000 ng/ml). The relative errors and C.V. of quality control samples were within 4.00 and 5.88%, respectively (furosemide concentrations: 5, 100 and 1000 ng/ml).


Subject(s)
Chromatography, High Pressure Liquid/methods , Diuretics/blood , Furosemide/blood , Humans , Reference Standards , Reproducibility of Results
20.
Arzneimittelforschung ; 46(6): 594-600, 1996 Jun.
Article in English | MEDLINE | ID: mdl-8767349

ABSTRACT

The disposition of candesartan cilexetil (CAS 145040-37-5, TCV-116) was studied after oral administration of 14C-labeled drug to rats and dogs. Candesartan cilexetil was absorbed from the small intestine and hydrolyzed completely to the pharmacologically active metabolite M-I during absorption process. In the plasma of these animals, an appreciable amount of M-I was present with no detectable concentration of unchanged drug. The M-I concentration in rat plasma attained a peak (Cmax, 0.280 microgram/ml) 2.3 h (Tmax after dosing and then declined with an apparent half-life (t1/2) of 3.8 h. In dogs, Tmax, Cmax, and t1/2 of M-I were 1.3 h, 0.012 microgram/ml, and 4.3 h, respectively. The bioavailabilities of M-I in rats and dogs were 28 and 5%, respectively. M-I was distributed widely in the tissues including the blood vessels as target tissues, was metabolized partially to the glucuronide and M-II, and was eliminated predominantly into the feces via biliary excretion. The elimination of M-I from the blood vessels was slower than that from the plasma. The sustained antihypertensive effect of this drug seemed to be due to the slow elimination of M-I from the blood vessels. With daily oral dosing for 14 days, no appreciable amounts of drug-related compounds were accumulated in rat body.


Subject(s)
Angiotensin II/metabolism , Angiotensin Receptor Antagonists , Benzimidazoles/pharmacology , Biphenyl Compounds/pharmacology , Tetrazoles , Animals , Bile/metabolism , Biological Availability , Dogs , Feces/chemistry , Half-Life , Intestinal Absorption , Male , Rats , Rats, Wistar , Tissue Distribution
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