Management consideration for patient with a large solitary fibrous tumor occupying the infratemporal fossa: A case report

The solitary fibrous tumor (SFT) was first described as a mesenchymal tumor of fibroblastic type, present in the pleura. The head and neck area is the third most common site of SFT occurrence. Numb chin syndrome (NCS) is a rare neurological symptom. The current report describes the case of a 39-year-old female patient referred to the present hospital with NCS, which was later observed to be due to a large SFT in the infratemporal fossa. Computed tomography and magnetic resonance images were taken and subsequent examination of these images revealed a space occupying mass (52×50×40 mm) in the infratemporal fossa. An open biopsy was performed on the lower part of the right auricula following angiography assisted vascular embolization of the maxillary artery. Pathological diagnosis was verified as SFT. Despite the tumor size and anatomical site, the SFT was successfully reduced in size by treatment with intensity modulated radiation therapy (IMRT) alone, with no recurrence. IMRT treatment of SFT may be effective as a future potential option for locally advanced head and neck SFT.

Gene expression analyses associated with malignant phenotypes of metastatic sub-clones derived from a mouse oral squamous cell carcinoma Sq-1979 cell line

To elucidate the genetic events that occur during the development of OSCC, the present study established a model of oral malignancy using a mouse oral squamous cell carcinoma (OSCC) Sq-1979 cell line. Sq-1979 cells were implanted into syngeneic C3H mice. Subsequently, 233 cells and metastatic sub-clones (L cells) from primary OSCC, as well as the metastasized lymph node tissues of Sq-1979-implanted mice were established. Compared with parental Sq-1979 and 233 cells, the majority of L cells exhibited a higher proliferation rate and transplantability, and conferred a lower survival rate on the implanted mice. To investigate the genetic background of L cells, preferentially expressed genes in L cells were identified by cDNA microarray and reverse transcription-polymerase chain reaction analyses. The expression of FYN-binding protein (Fyb), solute carrier family 16 member 13 (Slc16a13), keratin 7, transmembrane portion 173 and Slc44a3 mRNAs was significantly elevated in L cells compared with that in Sq1979 and 233 cells. The mRNA expression was also evaluated in human OSCC and leukoplakia (LP) tissues. Among the 5 aforementioned mRNAs, the expression of FYB and SLC16A13 was significantly higher in OSCC than in LP tissues. Furthermore, the expression of SLC16A13 mRNA was significantly elevated in highly invasive OSCCs, which were classified as grades 3 and 4 by the Yamamoto-Kohama (YK) classification of invasion, compared with those in lower grades (YK-1 and -2). The model proposed in the present study could thus describe essential marker genes for the diagnosis of oral malignancies.

Three-Dimensional Study of the Terminal Portion in Sprague-Dawley Rat Ejaculatory Ducts

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.

Producing Capabilities of Interferon-gamma and Interleukin-10 in Peripheral Blood from Oral Squamous Cell Carcinoma Patients

In order to evaluate the Th1 and Th2 responses of Oral Squamous Cell Carcinoma (OSCC) patients, we investigated the cytokine producing capability of peripheral blood (PB), and compared it with clinicopathological appearances of OSCC patients. The production of a Th1-type cytokine, interferon (IFN)-γ, from lipopolysaccharide (LPS)-stimulated PB correlated positively with the frequency of lymph node metastasis. We also investigated the production of a Th2-type cytokine, IL-10, however, no significant correlation was observed with the clinicopathological appearances. Our results suggested that the IFN-γ producing capability was specifically regulated and dependent on the regional metastatic potencies of OSCCs.

Symmetrical lipomatosis of the tongue: Case report and literature review

Multiple symmetric lipomatosis is rare and characterized by diffuse growth and nonencapsulated lipomas. It is usually found in the posterior neck and upper trunk, and the entity is known as "benign symmetric lipomatosis," "Madelung disease," and "Launois-Bensaude syndrome." Symmetric lipomatosis of the tongue was first described by Desmond and is an extremely rare condition. A 74-year-old man complained of painless tongue swelling and difficulty speaking. Clinical findings revealed no tumor masses on the trunk, limbs, or head and neck region. Intraoral findings included soft yellowish masses with a smooth surface without erosions on the side of the tongue bilaterally. They were 30 mm in diameter. An incisional biopsy was taken from the mass, and the lipoma was diagnosed. The bilateral tongue lesions were resected under general anesthesia. Intraoperative findings revealed adipose tissues interspersed with lingual muscles and no capsulation. The lesion was finally diagnosed as symmetric lipomatosis of the tongue based on clinical findings and radiological and histologic examination.

Increase of peripheral blood CD57+ T-cells in patients with oral squamous cell carcinoma

BACKGROUND/AIM

The subset of T-cells positive for expression of cluster of differentiation (CD) 57 has been associated with various cancer phenotypes. However, the presence of CD57(+) T-cells in patients with oral squamous cell carcinoma (OSCC) has yet to be confirmed. In the present study, we examined the diagnostic significance of the presence of CD57(+) T-cells in peripheral blood (PB) from patients with OSCC.

MATERIALS AND METHODS

The subset of CD57(+) T-cells in PB was analyzed in 43 patients with OSCC by fluorescence-activated cell sorting (FACS) analysis.

RESULTS

The proportion of CD57(+) T-cells, including both CD8(+) and CD4(+) subsets, significantly increased with clinical stage, especially in parallel with tumor size.

CONCLUSION

Our results suggest that an increase in the population of CD57(+) T-cells is a potent prognostic marker and may also influence the systemic immunity of patients with OSCC.

Primary intraosseous carcinoma arising from an odontogenic cyst: A case report

Cyst-like lesions in the mandible rarely develop into malignancies, and the reported incidence is between 0.3 and 2%. The present study describes a rare case of primary intraosseous squamous cell carcinoma of the mandible arising from an odontogenic cyst. A 59-year-old female was referred to Asahi University Murakami Memorial Hospital (Gifu, Japan), with acute pain in the right molars. An initial examination revealed buccal swelling and paresthesia of the mental nerve. Following an intraoral examination, the oral mucosa was confirmed to be normal, however, percussion pain was experienced between the lower right first premolar and second molar. Panoramic radiography revealed a retained lower right wisdom tooth and an irregular radiolucent area between the lower right molar and a mandibular angle with unclear margins. Computed tomography revealed diffuse bone resorption and an extensive loss of cortical bone on the buccal and lingual sides. A biopsy was performed and the pathological diagnosis was of a squamous cell carcinoma arising from the epithelial lining of the odontogenic cyst. Radical dissection was subsequently performed, however, histopathological examination of the resected specimen revealed neither invasion into the surrounding tissues penetrating the periosteum nor lymph node metastasis at the right submandibular lesion. Following the pathological diagnosis of primary intraosseous carcinoma (PIOC), the patient received 6,000 Gy radiation as post-operative radiotherapy and chemotherapy with oral administration of tegafur, gimeracil and oteracil potassium. The patient is currently undergoing follow-up examinations. Although PIOC arising from an odontogenic cyst is rare, it should be considered as a differential diagnosis for radiolucency of the jaw bone, particularly in older patients exhibiting a history of cystic lesions.

Nanoscale patterning induced strain redistribution in ultrathin strained Si layers on oxide

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.

Profile of bilateral anterior cruciate ligament injuries: a retrospective follow-up study

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.

Enhanced adhesion of oxidized mouse polymorphonuclear leukocytes to macrophages by a cell-surface sugar-dependent mechanism

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.

[Prevalence of dental erosion caused by sulfuric acid fumes in a smelter in Japan]

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.

Complete two-dimensional separation for analysis of acidic compounds in plasma using column-switching reversed-phase liquid chromatography

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.

Bone reactions to titanium screw implants in ovariectomized animals

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.

Bone reactions around hydroxyapatite-coated implants in ovariectomized rats

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.

Double column-switching high-performance liquid chromatographic method for the determination of TAK-603 and its metabolites in human serum

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.

Disposition of the new antirheumatic agent ethyl 4-(3,4-dimethoxyphenyl)- 6,7-dimethoxy-2-(1,2,4-triazol-1-ylmethyl)quinoline-3-carboxylate (TAK-603) in rats and dogs

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.

High-performance liquid chromatographic determination of seratrodast and its metabolites in human serum and urine

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.

Disposition of the new antidiabetic agent pioglitazone in rats, dogs, and monkeys

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.

Studies on the metabolism of the new antidiabetic agent pioglitazone. Identification of metabolites in rats and dogs

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.

Characterization of conjugated metabolites of a new angiotensin II receptor antagonist, candesartan cilexetil, in rats by liquid chromatography/electrospray tandem mass spectrometry following chemical derivatization

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.

High-performance liquid chromatography using on-line solid-phase extraction: determination of furosemide in human serum

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).

Disposition of the new angiotensin II receptor antagonist candesartan cilexetil in rats and dogs

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.

Quantitation of a new potent angiotensin II receptor antagonist, TCV-116, and its metabolites in human serum and urine

A sensitive high-performance liquid chromatographic (HPLC) method is described for the determination of a new potent antihypertensive agent, TCV-116, and its two metabolites (M-I and M-II) in human serum or urine. After pre-treatment of the specimens, the analytes were determined using a column switching technique, except for the metabolites in urine which were determined by gradient elution mode HPLC. The quantitation limits for TCV-116, M-I and M-II were all 0.5 ng/ml in serum, and 0.5, 10 and 110 ng/ml in urine, respectively. The methods were applied to clinical trials of TCV-116.

High-performance liquid chromatographic determination of pioglitazone and its metabolites in human serum and urine

A high-performance liquid chromatographic (HPLC) method for the simultaneous determination of pioglitazone and its metabolites (M-I to M-V) in human serum and urine was developed. The method for serum involved the solid-phase and liquid-liquid extraction. Urine with and without enzymatic hydrolysis using beta-glucuronidase was treated with liquid-liquid extraction. The compounds in the extract were analyzed using HPLC with UV detection at 269 nm. The detection limits of pioglitazone, M-I, M-II, M-III, M-IV, and M-V in serum were 0.01-0.05 micrograms/ml, those in urine were 0.1-0.5 micrograms/ml, and those in urine after enzymatic hydrolysis were 0.3-0.5 micrograms/ml, respectively. The method was applied to the clinical trials of pioglitazone.

Histologic and microradiologic comparison of block and particulate cancellous bone and marrow grafts in reconstructed mandibles being considered for dental implant placement

PURPOSE

Patterns of healing were investigated in mandibles reconstructed with three different techniques to assess their readiness for implant placement.

PATIENTS AND METHODS

The subjects were 10 patients who had undergone mandibular reconstruction with either nonvascularized iliac block bone grafts (group 1; 3 patients), particulate cancellous bone and marrow (PCBM) grafts (group 2; 3 patients) for mandibular discontinuity, or PCBM grafts for mandibular marginal defects (group 3; 4 patients). Six (groups 2 and 3) or 12 months (group 1) after mandibular reconstruction, bone biopsy specimens were obtained for histologic examination with a trephine bur. As controls, bone specimens were obtained from ungrafted mandibles of patients undergoing dental implant placement. Undecalcified specimens were embedded in polyester resin and examined by routine light microscopy and microradiography.

RESULTS

The morphology of the specimens from group 1 was similar to that of group 2, but not to that of the control subjects. However, the morphology of specimens from group 3 was generally similar to that of control subjects.

CONCLUSION

These results suggest that mandibular reconstruction with PCBM grafts allows the placement of dental implants sooner than reconstruction with block bone grafts.

Development and validation of column-switching high-performance liquid chromatographic methods for the determination of a potent AII receptor antagonist, TCV-116, and its metabolites in human serum and urine

Column-switching HPLC methods have been developed and validated for the determination of a new antihypertensive prodrug, TCV-116 (I), and its metabolites, CV-11974 (II) and CV-15959 (III), in human serum and urine. Initial sample cleanup was achieved by extracting the analytes into an organic solvent. After chromatographing on an ODS column with a mobile phase consisting of acetonitrile and an acidic phosphate buffer, the zone of the analyte's retention was heart-cut onto a second ODS column with a mobile phase of acetonitrile and a phosphate buffer at a higher pH. Complete separation of the analytes and the endogenous peaks was accomplished by the two-dimensional chromatography. Good precision and linearity of the calibration standards, as well as the inter-day and intra-day precision and accuracy of quality control samples, were achieved. The limit of quantitation (LOQ), using 0.5 ml of serum, was 2 ng/ml for I, 0.8 ng/ml for II, and 0.5 ng/ml for III. The LOQ for urine sample was 10 ng/ml for II and III. Stability of the analytes during storage, extraction, and chromatography processes was established. The results illustrate the versatile application of column switching to method development of multiple analytes in various biological matrices. The methods have been successfully used for the analyses of I and its metabolites in thousands of clinical samples to provide pharmacokinetic data.

Sensitive determination of methotrexate in monkey plasma by high-performance liquid chromatography using on-line solid-phase extraction

A high-performance liquid chromatographic method was developed for the sensitive determination of methotrexate (MTX) in monkey plasma using direct injection and on-line solid-phase extraction. After application of a 100-microliters aliquot of plasma to a pre-treatment column, the column was washed with 0.02 M phosphate buffer (pH 7) to eliminate plasma proteins and endogenous substances, and subsequently the adsorbed MTX was eluted. The MTX fraction was transferred to an analytical column by a column-switching (heart-cutting) technique, and MTX was analyzed using ion-pair chromatography with tetrabutylammonium bromide. More than 50 injections could be performed onto one pretreatment column. The accuracy, precision, reproducibility and linearity were satisfactory over a wide range of MTX concentrations (5-1000 ng/ml). The quantitation limit was 5 ng/ml with a signal-to-noise ratio of 5. The method was suitable for the pharmacokinetic study of MTX in monkey.

Sensitive high-performance liquid chromatographic determination of EM523, a new erythromycin derivative, in human plasma and urine with ultraviolet detection using column switching

A sensitive high-performance liquid chromatographic (HPLC) method using column switching is described for the determination of EM523 (I), a new erythromycin derivative, in human plasma and urine. The analyte was extracted from alkalinized plasma or urine with a mixture of n-hexane and acetone. After the evaporation of the organic layer, the reconstituted residue was injected into the HPLC system and separated on the first column. After column switching, the heart-cut fraction contamination the analyte was further separated on the second column and monitored by ultraviolet absorbance at 210 nm. The detection limits were 1 ng/ml in plasma and 10 ng/ml in urine. The method was applied to the clinical trials of I.

Sensitive high-performance liquid chromatographic determination of 2,2'-[(2-aminoethyl)imino]diethanol bis(butylcarbamate) and its metabolites in human serum following pre-column derivatization with o-phthalaldehyde and stabilization of the derivatives

A high-performance liquid chromatographic method for the sensitive determination of 2,2'-[(2-aminoethyl)imino]diethanol bis(butylcarbamate) (I) and its metabolites in human serum has been developed. The method was based on a pre-column derivatization with o-phthalaldehyde. The derivatives were stabilized at least for 24 h at 4 degrees C by using N-acetyl-L-cysteine as a thiol and by eliminating the excess o-phthalaldehyde in the reaction mixture by solvent extraction and the addition of an ammonium salt after the reaction. The recoveries and reproducibilities in human serum spiked with I and its two metabolites were satisfactory, and the responses were linear over a wide range of analyte concentrations. The detection limits of I and its metabolites, II and III, in serum were 0.5, 4 and 2 ng/ml, respectively, at a signal-to-noise ratio of 5. The method was satisfactorily applied to the clinical study of I.

Automated high-performance liquid chromatographic method for the simultaneous determination of cefotiam and delta 3-cefotiam in human plasma using column switching

An automated high-performance liquid chromatographic method using column switching was established for the simultaneous determination of cefotiam (I) and delta 3-cefotiam (II) in human plasma after oral administration of cefotiam hexetil dihydrochloride. The method allowed the determination of analytes in plasma by the direct injection of diluted specimen with phosphate buffer. The analytes were enriched onto the C18 short pretreatment column by 0.05 M phosphate buffer (pH 7.7), while proteins and endogenous hydrophilic substances in plasma were washed off to waste. The enriched analytes were then back-flushed onto the analytical C18 column, separated by a mixture of 0.05 M phosphate buffer (pH 7.7)-acetonitrile (88:12, v/v) and detected by the ultraviolet absorbance at 254 nm. Recoveries from spiked plasma were quantitative, and the coefficients of variation were below 4%. The lower detection limits in plasma were 10 ng/ml for both I and II. Concentrations of I and II in plasma determined by the present method were in good agreement with those obtained by the conventional deproteinization method.

Column-switching techniques for high-performance liquid chromatography of ibuprofen and mefenamic acid in human serum with short-wavelength ultraviolet detection

Column-switching techniques for high-performance liquid chromatography of two acidic drugs, ibuprofen and mefenamic acid, in human serum with short-wavelength ultraviolet detection are described. The method involved extraction of the analyte from acidified serum followed by the chromatographic analysis using column switching. Three ODS columns were used each with different mobile phase, utilizing the difference of ion-pair formation or of ionization caused by pH change. The method offered high sensitivity and selectivity, with short-wavelength ultraviolet detection at 221 nm for ibuprofen and at 219 nm for mefenamic acid. The detection limits were 0.5 ng/ml (2.4 pmol/ml) for ibuprofen and 0.1 ng/ml (0.4 pmol/ml) for mefenamic acid using 1 ml of serum, both at a signal-to-noise ratio of 3. With some modifications, the principle of the method would be applicable to other acidic compounds in biological fluids.

Clinical course and roentgenographic changes of osteonecrosis in the femoral condyle under conservative treatment

The history of osteonecrosis in the femoral condyle of the knee was observed in 15 knees in 14 patients, averaging 62.8 years in age (range, 23-79 years). There were nine women and five men. The average follow-up period was 4.9 years (range, one to 12 years). Spontaneous osteonecrosis was found in 11 patients and steroid-induced osteonecrosis in three. The medial femoral condyles were involved in 13 knees and the lateral femoral condyles in two. The maximum width of the lesion was measured on anteroposterior roentgenograms and an osteonecrotic lesion less than 10 mm wide was rated as small. Cases of small osteonecrotic lesions displayed no remarkable changes with respect to stages and limb alignment. The average size of the steroid-induced osteonecrotic lesions was significantly larger than that of the spontaneous type. The size of the osteonecrotic lesions at the follow-up examination was compared to that observed at the initial diagnosis in 12 knees. Eight of these lesions displayed increases in dimension of more than 18% over the initial size at diagnosis.

High-performance liquid chromatographic determination of phenylpropanolamine in human plasma and urine, using column switching combined with ion-pair chromatography

A highly sensitive and selective high-performance liquid chromatographic method with ultraviolet detection at 205 nm, without prior derivatization, is described for the determination of phenylpropanolamine in human plasma and urine. The method involved extraction of plasma or urine at a basic pH with diethyl ether, and chromatographic analysis using column switching combined with ion-pair chromatography. In the first octadecylsilica column, the drug was preseparated from endogenous substances in samples by ion-pair chromatography. After column switching, in the second octadecylsilica column, the heart-cut fraction containing the analyte was further separated by reversed-phase chromatography. The detection limits were 0.4 ng/ml in plasma and 8 ng/ml in urine, both at a single-to-noise ratio of 3. The method was applied to the determination of the drug in plasma and urine after oral administration of 25 mg of phenylpropanolamine hydrochloride in water to a healthy human volunteer.

[Basic study on the chemosensitivity test by miniaturized improved nucleic acid precursor incorporation assay (MINI assay)]

Miniaturized improved nucleic acid precursor incorporation assay (MINI assay) has been developed by Kern D. H. and Tanigawa N. et al since 1985. We investigated in vitro effects of mitomycin C (MMC), cisplatin (CDDP) and bleomycin (BLM) against A 549 lung cancer cells and HeLa cells by MINI assay.

RESULTS

3H-thymidine (3H-TdR) uptake in the positive control was 734.2 cpm +/- 10 cpm. The cut-off level for in vitro sensitivity was defined as more than 80% inhibition of 3H-TdR uptake in the drug treated cells compared to the positive controls. A 549 cells were sensitive to MMC (81.6%), CDDP (78.6%), but not to BLM (-57%). HeLa cells were sensitive to MMC (91%), CDDP (79.4%), but not to BLM (43%). MINI assay could be done with fewer cells than other methods and the results were obtained within 5 days. This method was considered to be useful for the chemosensitivity test with human tumors.

Determination of manidipine and its pyridine metabolite in human serum by high-performance liquid chromatography with ultraviolet detection and column switching

A highly sensitive and selective high-performance liquid chromatographic method using column switching is described for the determination of the dihydropyridine calcium antagonist manidipine (I),2-[4-(diphenylmethyl)-1-piperazinyl]ethyl methyl (+/- )-1,4-dihydro-2,6-dimethyl-4-(m-nitrophenyl)-3,5- pyridinedicarboxylate, and its pyridine metabolite (II), 2-[4-(diphenylmethyl)-1-piperazinyl]ethyl methyl 2,6-dimethyl-4-(m-nitrophenyl)-3,5-pyridinedicarboxylate, in human serum. The method is based on the combination of the column-switching technique and ion-pair chromatography. In the first ODS column, I and II are preseparated from endogenous substances in serum with a mobile phase containing sodium nonane sulphonate as an ion-pair reagent. After column switching, in the second ODS column, the heart-cut fraction containing I and II is further separated from the co-eluted substances through the first column with a mobile phase containing no ion-pair reagent. By using microbore columns with a diameter of 2.1 mm, the sensitivity is almost double that given by conventional bore columns with a diameter of 4.6 mm. The method offers high sensitivity and selectivity with short-wavelength ultraviolet detection at 230 nm. The detection limits of both I and II are 0.1 ng/ml using 1 ml of serum. The method is suitable for the pharmacokinetic study of I.2HCl after oral administration to man.

Sensitive high-performance liquid chromatographic determination of ionic drugs in biological fluids with short-wavelength ultraviolet detection using column switching combined with ion-pair chromatography: application to basic compounds

A highly sensitive and selective high-performance liquid chromatographic method with short-wavelength UV detection is described for the determination of ionic compounds in biological fluids, which was applied to two basic compounds, 2-(3-[4-(4-fluorophenyl)-1-piperazinyl]propyl)-6,7,8,9-tetrahydro-2H-nap htho [2,3-b][1,4]oxazin-3(4H)-one (I) and methyl 2-(4-diphenylmethyl-1-piperazinyl)ethyl (+/-)-1,4-dihydro-2,6-dimethyl-4-(m-nitrophenyl)-3,5-pyridinedicarboxyla te (II), in human serum. The method is based on the combination of the column-switching technique and ion-pair chromatography. In the first ODS column, the analyte is pre-separated from endogenous substances in serum by ion-pair chromatography. After column switching, in the second ODS column the heart-cut fraction containing the analyte is further separated by non-ion-pair chromatography from coeluted endogenous substances from the first ODS column. The proposed method offered high sensitivity and selectivity with UV detection at 215 nm for I and 230 nm for II. The detection limits were 0.2 ng/ml for both I and II using 1 ml of serum. The principle of the proposed method would be applicable to both acidic and basic compounds in biological fluids with a suitable ion-pair reagent.