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Biomedical subjects

S Tachibana

Publications and source records attributed to S Tachibana.

At least 19 recordsLinked to original sources

Simultaneous determination of testosterone metabolites in liver microsomes using column-switching semi-microcolumn high-performance liquid chromatography.

A sensitive and selective column-switching semi-microcolumn high-performance liquid chromatographic (HPLC) method has been developed for the simultaneous determination of testosterone and eight of its metabolites (6alpha-, 6beta-, 16alpha-, 16beta-, 7alpha-, 2alpha-, and 2beta-hydroxytestosterone, and androstenedione) in liver microsomes. After incubation for 10 min, testosterone and its metabolites were extracted from the microsomes with ethyl acetate, and the extract was evaporated to dryness. The residue was dissolved in the mobile phase and loaded onto the HPLC system. The analytes were first concentrated in a precolumn and subsequently transferred to the analytical column, where they were separated using linear gradient elution. A UV detector set at 254 nm was used to detect the analytes. This newly developed method clearly separated TES and the metabolites with high resolution and was found to be reproducible with intra- and interday variability of <10.7%. This method has been subsequently used to determine the testosterone hydroxylation activities catalyzed by 15 different recombinant CYP isozymes. The results confirmed the formation of stereoselectively hydroxylated metabolites by each CYP isozyme.

Animals↗

Neutral endopeptidase/CD10 and aminopeptidase N/CD13 gene expression as a prognostic factor in non-small cell lung cancer.

OBJECTIVES: Neutral endopeptidase modulates the growth of lung cancer, while aminopeptidase N degrades the extracellular matrix and is involved in cell motility. We studied the metastasis mechanism to detect novel metastasis-associated molecules and to evaluate them for clinical application. METHODS: We studied the relationship between the expression of neutral endopeptidase and aminopeptidase N by quantitative reverse transcript-polymerase chain reaction analysis in 132 patients with non-small cell lung cancer undergoing radical surgery from 1991 to 1996. RESULTS: Patients with neutral endopeptidase-positive and aminopeptidase N-negative tumors were defined as group A, those with neutral endopeptidase-positive and aminopeptidase N-positive or neutral endopeptidase-negative and aminopeptidase N-negative tumors as group B, and those with neutral endopeptidase-negative and aminopeptidase N-positive tumors as group C. The 5-year survival of group A patients (92.9%) was significantly better than that of group B patients (64.7%) and much better than that of group C patients (38.2%) (P = 0.0011). Neutral endopeptidase and aminopeptidase N thus have statistically significant P in overall survival in Cox regression (P = 0.019). CONCLUSION: Neutral endopeptidase and aminopeptidase N gene expressions are significant indicators of prognosis.

Adult↗

Usefulness of tc-99m MIBI SPECT in predicting multidrug resistance gene expression levels in non-small cell lung cancer--a preliminary report.

In this study we investigated whether Tc-99m hexakis 2-methoxy isobutyl isonitnile (Tc-99m MIBI) single-photon emission computed tomography (SPECT) has a correlation with the multidrug resistance (MDRI) and multidrug resistance-associated protein (MRP1) gene expression levels in non-small cell lung cancer (NSCLC). Fifteen patients with NSCLC were studied. SPECT images were obtained 15 (early) and 120 (delayed) min after injection of Tc-99m MIBI. We chose only one transverse section and set the region of interest over the tumor and out of the body. The mean counts in the tumor on early and delayed images were corrected by using those in the background and represented as Te and Td, respectively. Resected tumor specimens were frozen with liquid nitrogen and each positive control cell line was cultured. After the total ribonucleic acid (RNA) was extracted from specimens and cell lines, the complimentary deoxyribonucleic acid (cDNA) was amplified by the reverse transcription-polymerase chain reaction (RT-PCR) method. Each product was electrophoresed and fluorointensity was measured. The gene expression level was represented as the ratio of that of the positive control cell line. Te and Td indicated a significant correlation with the MDR1 gene expression level (p = 0.015 and p = 0.022), but not the gene of MRP1 (p = 0.100 and p = 0.145). In conclusion, Te and Td are useful parameters in predicting the MDRI gene expression level, but not MRPI in NSCLC.

Aged↗

Spinal tanycytic ependymomas.

Three cases of spinal tanycytic ependymoma are reported, a man aged 45 years and two women aged 36 and 55 years. Each patient developed gradual paraparesis over a few months prior to admission. Magnetic resonance imaging showed an enhancing, well-circumscribed tumor in the spinal cord in each case. Histologically, the tumors consisted of monotonous proliferation of long spindle cells with markedly eosinophilic cell processes; focally forming perivascular pseudorosettes. The tumor cells were strongly immunopositive for glial fibrillary acidic protein, S-100 protein and vimentin. Ultrastructurally, in addition to massive intermediate filaments, many tumor cells showed abundant microtubules. Well-developed desmosomes and microvilli/cilia-lined microlumina were occasionally observed. The tumors were grossly totally removed and the patients remain recurrence free at 9, 9, and 2 years postoperatively. Reviewing reported cases including our three cases, tanycytic ependymoma may occur frequently in spinal cord, especially in the cervical region of the spinal cord. Since histologically it resembles pilocytic astrocytoma and schwannoma, tanycytic ependymoma should be included in the differential diagnosis of benign spindle cell tumors of the central nervous system.

Adult↗

Hepatocellular carcinoma with a sarcomatous appearance: report of a case.

A 59-year-old man was admitted with general fatigue, an epigastric mass, and remittent fever. Radiological examinations disclosed a huge solid-to-cystic mass in the right lobe of the liver, and the mass severely compressed the right diaphragm, the inferior vena cava, and the right atrium. In addition, the patient suffered from chronic hepatitis; however, the serum alpha-fetoprotein, carcinoembryonic antigen, and PIVKA II levels were all within the normal ranges. The serum C-reactive protein level was 7.71mg/dl. With a clinical diagnosis of a malignant hepatic tumor invading the right diaphragm, surgery was performed. The tumor originated from segments IV and VII of the liver, was well defined, and grew extrahepatically. The tumor was resected using an ultrasonic cavitational aspirator together with the infiltrated right diaphragm. The resected tumor measured 23 x 13 x 23cm in size and weighed 3,700 g. Histologically, the tumor was found to consist of hepatocellular carcinomatous component and sarcomatous component. In the sarcomatous component, spindle-shaped cells which were positive for the immunohistochemical localization of vimentin, alpha-smooth muscle actin, and keratin were identified. The postoperative course was uneventful. The value of the serum C-reactive protein returned to within the normal range, and the patient became afebrile. The patient received a postoperative combination chemotherapy (etoposide, epirubicin, and cisplatin), and remains well with no signs of recurrence 12 months after the operation.

Carcinoma, Hepatocellular↗

The use of ultrasound for drug delivery.

Ultrasound has been in use for the last three decades as a modality for diagnostic imaging in medicine. Recent studies have shown that nonthermal ultrasound energy could be applied for targeting or controlling drug release. This new concept of therapeutic ultrasound combined with drugs has induced interest in various medical fields. Enhanced effects of thrombolytic agents such as urokinase and TPA with acoustic energy have been demonstrated. Ultrasound transducer-tipped catheters are being developed for treatment of cardiovascular diseases. Other devices with ultrasound transducers implanted in transdermal drug patches are also being evaluated for possible delivery of insulin through the skin. Echo contrast microbubbles could also be used to carry and release genes to various tissues and lesions. Chemical activation of drugs by ultrasound energy for treatment of cancers is another new field recently termed "sonodynamic therapy." Various examples of ultrasound application are under investigation that could lead to revolutionary drug delivery systems of the future.

Drug Delivery Systems↗

One-portal technique of endoscopic fasciotomy: Chronic compartment syndrome of the lower leg.

Many athletes complain of exercise-induced pain in the lower leg that can be caused by inflammatory diseases, peripheral nervous system disease, fatigue fracture, shin splint, and chronic compartment syndrome (CCS). CCS is the most typical exercise-induced condition and it often requires surgical decompression of the several compartments. There are already many techniques reported in the literature. Recently, an endoscopic technique for CCS was reported with which excellent results were achieved. We have modified it and developed a new technique for treating CCS of the lower leg. We report a case of CCS of the lower leg treated with 1-portal endoscopic fasciotomy. The technique helps to decrease damage to soft tissue and patients will immediately return to normal activities of daily living.

Adolescent↗

A case report of early idiopathic portal hypertension.

We report herein a case (46 years, female) of very early idiopathic portal hypertension. During an examination for in situ uterine cervical cancer, splenomegaly and hypersplenism were incidentally found. CT and MRI showed a nonatrophic liver with dilated portal veins and marked splenomegaly. The portal venous blood flow was increased, while portal venous blood pressure was not high. The spleen (1,220 g) showed hyperplasia of white pulp and congestion. The lobular architecture of the liver was well-preserved, and the subcapsular regions were not atrophic or dropped out. The portal tracts were not fibrotic, and portal veins were neither stenotic nor sclerotic. Instead, lymphoid cell infiltrations were found in about half the portal tracts, and there was subendothelial mononuclear cell infiltration of small portal vein branches. The hepatic lobules showed non-specific reactive change. This case suggests that early hepatic changes recognizable histologically in this disease are lymphoid cell infiltration of the portal tract and of subendothelial regions of portal vein branches, and nonspecific lobular hepatitis. These hepatic changes, as well as marked splenomegaly, may represent an altered immunophenomenon of this disease.

Carcinoma in Situ↗

Clinical significance of CD151 gene expression in non-small cell lung cancer.

Transmembrane 4 superfamily (TM4SF) is a recently described gene family, and TM4SF members are known to play roles in the signal transduction pathways and to regulate cell activation, development, proliferation, and motility. MRP-1/CD9, KAI1/CD82, and ME491/CD63, members of the TM4SF, have been reported to suppress tumor progression or metastasis. Previously, we showed that MRP-1/CD9 suppressed cell motility and metastatic potential to lungs. Moreover, reduction of MRP-1/CD9 and KAI1/CD82 gene expression was found to be a factor in a poor prognosis for patients with non-small cell lung cancer. However, among TM4SF, CD151 is identical to an existing gene, PETA-3, which may promote tumor metastasis of malignant cells, and its expression may be involved in the malignant progression of cancer. The function of CD151 is opposite that of the metastasis suppressor genes, MRP-1/CD9 and KAI1/CD82. On the basis of these results, we used reverse transcription-PCR and immunohistochemical techniques for a retrospective study of CD151 gene expression in tumor tissues from 145 lung cancer patients; 72 tumors were stage I, 29 stage II, 27 stage IIIA, and 17 stage IIIB. Whereas 86 patients had tumors positive for the CD151 gene, 59 had tumors that were negative for the CD151 gene. The overall survival rate of patients with CD151-positive tumors was much lower than that of CD151-negative patients (51.9% versus 73.1%; P = 0.013). Our findings suggest that high CD151 gene expression in lung cancer may be associated with a poor prognosis. Assessment of CD151 could be instrumental for improvements in lung cancer diagnosis and therapies.

Antigens, CD↗

Structural factors for the formation of propellane-type products in the solvolysis of bicyclic bridgehead compounds

Methanolyses of 2-oxobicyclo[3.3.1]non-1-yl triflate, 3, 3-dimethyl-2-oxobicyclo[3.3.1]non-1-yl triflate, and 2-oxobicyclo[4. 3.1]dec-1-yl mesylate gave the corresponding propellanone in 12%, 20%, or 3.2% yield, respectively, beside substitution or rearranged products under typical conditions. No propellane-type product was obtained in the solvolyses of 1-bromobicyclo[3.3.1]nonane, 2-methylidenebicyclo[3.3.1]non-1-yl heptafluorobutyrate, and 3, 3-dimethyl-2-thioxobicyclo[3.3.1]non-1-yl tosylate. The factors that permit the formation of the propellane-type product from the intermediate bridgehead cations are examined with the aid of theoretical calculations at PM3 and B3LYP/6-31G.

Journal Article↗

Enlarged median nerve in idiopathic carpal tunnel syndrome.

To delineate change in median nerve size in carpal tunnel syndrome (CTS), we compared ultrasonograms of nerve cross-sections from patients (201 wrists of 125 women with idiopathic CTS) and controls (200 dominant wrists of 200 women). Major and minor axes, cross-sectional area, and the flattening ratio (major axis/minor axis) were measured at four levels: 1, distal edge of the flexor retinaculum; 2, center of the hook of the hamate; 3, wrist crease; and 4, distal one-third level of the forearm. Axes and areas were greater in the patients at levels 1, 2, and 3. The flattening ratio was greater in the controls at levels 1 and 2, and in the patients at level 3. When the groups were combined, there were linear correlations between the cross-sectional nerve area and electrophysiologic severity at levels 1, 2, and 3. These findings indicate that idiopathic CTS is characterized by severity-correlated intracarpal enlargement of the median nerve and not by compressive deformation, such as a reduction in the caliber of the nerve.

Adult↗

Video-assisted blebectomy using a flexible scope and a bleb implement.

We describe herein our new technique of performing video-assisted thoracic surgery (VATS) using a flexible scope and a bleb implement which allows for a reduction in the risk of overlooking small and flat blebs in patients with a spontaneous pneumothorax (SP). This technique was performed in 26 consecutive patients with a SP. A skin incision about 18 mm long was made in the area over which the patients had specified preoperatively, and meticulous observation of the apex and superior segment was performed using a bleb implement. Partial pneumonectomy with endoscopic staplers and laser ablation were carried out for pleural lesions. We found that VATS combined with a flexible scope and a bleb implement resulted in better visibility for detection and removal of any small and flat blebs.

Equipment Design↗

The synergistic effects of hyperthermia and anticancer drugs on induction of apoptosis.

We studied the synergistic effects of hyperthermia and anticancer drugs on induction of apoptosis in lung cancer cells (LK-2 and LU-65A) using in situ end-labeling of DNA, the DNA fragmentation assay, and transmission electron microscopy. A few apoptotic cells were detected only when both cell lines were heated at relatively high temperature (44 degrees C). Moderate numbers of apoptotic cells were observed when both cell lines were incubated with high concentrations (30 or 40 microM) of anticancer drug. Compared with hyperthermia or anticancer drug alone, the combined treatment induced many apoptotic cells in both cell lines, even in the cells treated with lower concentrations (6 or 8 microM) of anticancer drugs following mild hyperthermia (43 degrees C). In regard to kinetics of apoptotic cells induced by treatment, the maximum induction of apoptosis by the combined treatment was higher than that of hyperthermia or anticancer drug alone in both cell lines, although the time of the peak of apoptotic index differed among the three treatments. Therefore, "hyperthermo-chemotherapy" may reduce the required dosage of anticancer drug and decrease the temperature of hyperthermia on induction of apoptosis.

Antineoplastic Agents↗

Median nerve compression by a radially inserted palmaris longus tendon after release of the antebrachial fascia: A complication of carpal tunnel release.

We describe a case that had recurrent median nerve compression after release of the antebrachial fascia in carpal tunnel release. The nerve was compressed by a palmaris longus tendon that was inserted radially into the thenar fascia. After decompression (detachment of the tendon) the patient had symptom relief. Release of the antebrachial fascia in the presence of this tendon variant carries a risk of median nerve compression by the tendon.

Carpal Tunnel Syndrome↗

Involvement of polyamines in the chilling tolerance of cucumber cultivars.

The possible involvement of polyamines (PAs) in the chilling tolerance of cucumber (Cucumis sativus L. cv Jinchun No. 3 and cv Suyo) was investigated. Plants with the first expanded leaves were exposed to 3 degrees C or 15 degrees C in the dark for 24 h (chilling), and then transferred to 28 degrees C/22 degrees C under a 12-h photoperiod for another 24 h (rewarming). Chilling-tolerant cv Jinchun No. 3 showed a marked increase of free spermidine (Spd) in leaves, once during chilling and again during rewarming. Putrescine increased significantly during rewarming, but the increase of spermine was slight. Any of these PAs did not increase in chilling-sensitive cv Suyo during either period. PA-biosynthetic enzyme activities appear to mediate these differences between cultivars. Pretreatment of Spd to cv Suyo prevented chill-induced increases in the contents of hydrogen peroxide in leaves and activities of NADPH oxidases and NADPH-dependent superoxide generation in microsomes and alleviated chilling injury. Pretreatment of methylglyoxal-bis-(guanylhydrazone), a PA biosynthesis inhibitor, to chilled cv Jinchun No. 3 prevented Spd increase and enhanced microsomal NADPH oxidase activity and chilling injury. The results suggest that Spd plays important roles in chilling tolerance of cucumber, probably through prevention of chill-induced activation of NADPH oxidases in microsomes.

Adaptation, Physiological↗