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T Sakamoto

Publications and source records attributed to T Sakamoto.

At least 181 records · Page 10Linked to original sources
PubMed2001

Interleukin-11 enhances cell survival of decidualized normal human endometrial stromal cells.

High expression of interleukin-11 (IL-11) and the IL-11 receptor alpha chain in developing decidual cells in mice has been reported, and mice lacking IL-11 receptor expression have been reported to show impaired implantation owing to defective decidualization. However, the direct effect of IL-11 on endometrial stromal cells has not been studied. In this study, we examined the direct effects of IL-11 on normal human endometrial stromal cells using an in vitro decidualization assay system. IL-11 enhanced cell viability and prolactin secretion of 8-Br-cAMP-induced decidualized cells but not of non-stimulated stromal cells. IL-11 dose-dependently enhanced the viability of stromal cells co-stimulated with 8-Br-cAMP and IL-11 without any significant effect on prolactin secretion from the cells. The extracellular matrix did not affect the effect of IL-11 on the viability of 8-Br-cAMP-stimulated stromal cells. These results indicate that IL-11 enhances the viability of 8-Br-cAMP-stimulated stromal cells and of decidualized stromal cells, and that the cell survival signals generated by IL-11 are independent of those generated by the extracellular matrix. IL-11 produced locally in decidual tissues may enhance the viability of decidualized stromal cells and possibly protect against cell damage during embryo implantation and trophoblastic invasion.

8-Bromo Cyclic Adenosine Monophosphate↗
PubMed2001

[A case of pulmonary lymphangioleiomyomatosis in an elderly woman].

We encountered a postmenopausal woman in whom pulmonary lymphangioleiomyomatosis was pathologically diagnosed. Cases of pulmonary lymphangioleiomyomatosis are rare in postmenopausal women. The patient was the oldest in whom such a case was reported in the literature. Pulmonary lymphangioleiomyomatosis should be on the list of differential diagnoses for cases of pulmonary cystic lesions, even in postmenopausal women.

Aged↗
PubMed2001

[Functional outcome of primary pontine hemorrhage: conservative treatment or stereotaxic surgery].

In this study we compared the outcome of patients with primary pontine hemorrhage (PPH) in those who underwent stereotaxic aspiration and those treated non-surgically. Out of 75 PPHs, 37 patients were selected. Their consciousness on admission was somnolent to semicoma (alert and deeply comatose cases were excluded). Patients admitted between 1988 and 1990, and between 1995 and 1996 underwent CT guided stereotaxic aspiration (18 cases: Surgical Group), and those admitted between 1991 and 1994 were treated conservatively (19 cases: Conservative Group). The outcome was analyzed three months after the onset from the viewpoint of level of consciousness and severity of paresis, according to the location of the hemorrhage. With regard to consciousness, 13 of 18 cases in the Surgical Group showed remarkable improvement, while only 8 of 19 cases in the Conservative Group did. The severity of paresis was evaluated only among the patients who could obey commands three months after the onset. Paresis improved in 7 of 13 patients in the Surgical Group, vs. in 3 of 8 patients in the Conservative Group (p < 0.05). According to the location of hemorrhage (CT classification), in the Unilateral tegmental type and the Massive type, the Surgical Group and the Conservative Group showed no difference. On the other hand, in the Bilateral tegmental type and the Basal tegmental type, surgery seemed to be more effective than conservative treatment. In conclusion, CT guided stereotaxic aspiration may improve not only the consciousness level but also the functional outcome.

Adult↗
PubMed2001

[Pathologic findings both before and after steroid therapy in a case of desquamative interstitial pneumonia].

A 62-year-old man was admitted to our hospital because of dyspnea on effort. Histological findings from video-assisted thoracoscopic surgical biopsy were desquamative interstitial pneumonia (DIP). Two months after the introduction of steroid therapy, the patient underwent right middle lobe lobectomy for primary lung cancer. The histologic findings in this lobe revealed non-specific interstitial pneumonia, not characteristic of DIP. This case was the first in which histologic examination revealed DIP both before and after steroid therapy.

Humans↗
PubMed2001

[Good response in case of hepatocellular carcinoma with portal tumor thrombs--a case report of interdisciplinary local therapy].

A 56-year-old male patient with chronic C type hepatitis had HCC which invaded right portal vein trunk (Vp3). In August 2000, we performed intrahepatic artery infusion chemotherapy with CDDP and 5-FU under subcutaneous interferon alpha treatment. In addition, we used chemoradiation therapy for portal tumor thrombus in HCC. As the result of such therapy, the size of HCC and portal tumor thrombus reduced and the level of PIVKA-II decreased. There were no side effects except fever due to interferon alpha treatment. In February 2001, we performed devascularization and RFA therapy for HCC in S7 of liver under laparoscope. The level of PIVKA-II was within the normal range. It is important to perform interdisciplinary therapy appropriate for the HCC status.

Antineoplastic Agents↗
PubMed2000

Fractionated stereotactic radiotherapy for vestibular schwannoma (VS): comparison between cystic-type and solid-type VS.

PURPOSE: To compare the effectiveness and complications of fractionated stereotactic radiotherapy (SRT) for cystic-type vestibular schwannoma (VS) with those of solid-type VS. METHODS AND MATERIALS: In 65 patients treated with fractionated SRT between 1991 and 1999, 20 were diagnosed with cystic VS, in which at least one-third of the tumor volume was a cystic component on magnetic resonance imaging (MRI), and 45 were diagnosed with solid VS. Thirty-six Gy to 50 Gy in 20-25 fractions was administered to the isocenter and approximately 80% of the periphery of the tumor. All cystic and solid components were included in the gross tumor volume. The mean follow-up period was 37 months, ranging from 6 to 97 months. RESULTS: The actuarial 3-year rate of no episode of enlargement greater than 2.0 mm was 55% for cystic-type and 75% for solid-type VS; the difference was statistically significant (p = 0.023). The actuarial 3-year tumor-reduction (reduction in tumor size greater than 2.0 mm) rates were 93% and 31%, respectively (p = 0.0006). The overall actuarial tumor control rate (no tumor growth greater than 2. 0 mm after 2 years or no requirement of salvage surgery) was 92% at 5 years in 44 patients with a follow-up period of 2 or more years. There was no difference in the class hearing preservation rate between cystic VS and solid VS. No permanent trigeminal or facial nerve palsy was observed in either group. CONCLUSION: Transient tumor enlargement occurs in cystic VS more frequently than in solid-type VS, but the subsequent tumor-reduction rate in cystic VS is better.

Actuarial Analysis↗
PubMed2000

Plasma levels of A- and B-type natriuretic peptides in patients with hypertrophic cardiomyopathy or idiopathic dilated cardiomyopathy.

We investigated the relation between left ventricular structure and the secretion patterns of A- and B-type natriuretic peptides (ANP and BNP) by comparing their plasma levels in patients with hypertrophic cardiomyopathy (HC) and patients with idiopathic dilated cardiomyopathy (IDC). The secretion of ANP and BNP was much higher in patients with HC than in those with IDC; this shows that left ventricular cavity size is a key factor that regulates the secretion of ANP and BNP.

Aged↗
PubMed2000

Polymer support assisted selective functionalization of azoles using a palladium-catalyzed coupling reaction

Regioselective palladium-catalyzed monoarylation of azoles was achieved using iodobenzoate immobilized on an insoluble polymer support. The positional selectivity for the coupling reaction was dramatically influenced by the presence of CuI. No diarylation was observed in either case. Unsymmetrical diarylation was also obtained with the polymer support using sequential coupling reactions.

Journal Article↗
PubMed2000

Early molecular and cellular events of oxidant-induced pulmonary fibrosis in rats.

To evaluate the early molecular events of oxidant-induced pulmonary fibrosis, rats were continuously exposed to 0.4 ppm ozone and 7 ppm nitrogen dioxide. The early responses to the combined gases could be divided into three phases. Acute pulmonary inflammation indicated by an increase in pulmonary edema as well as an influx of neutrophils into the airspaces first occurred on days 1 to 3 of the exposure. The pulmonary inflammation was reversed by day 8, and no biochemical or morphologic aspects of tissue responses were detected from days 15 to 45, suggesting that rats adapted to the stimuli during that period. Pulmonary fibrosis could be detected by an increase in the biomarker of lung collagen content at day 60 and by histopathologic evaluation by day 90. Enhanced expression of macrophage inflammatory protein-2 was observed only at day 1, whereas the pulmonary expression of transforming growth factor-beta was upregulated on days 60 and 90 of the exposure. Macrophage expressions of interleukin-1beta and interleukin-6 were enhanced during acute pulmonary inflammation; however, macrophage expression of tumor necrosis factor-alpha was elevated at both day 1 and days 60-90. Activation of nuclear factor-kappa B and increased expression of thioredoxin in the lungs was also observed at day 1 and days 60-90. The expression of antioxidant enzymes, such as manganeous superoxide dismutase and glutathione peroxidase, was not altered during exposure. These results indicate that macrophage activation and the expression of macrophage-derived cytokines may play an important role in the early pulmonary responses against the combined gases.

Administration, Inhalation↗
PubMed2000

Preparation of completely 6-O-desulfated heparin and its ability to enhance activity of basic fibroblast growth factor.

Although regioselective removal of 6-O-sulfate groups of heparin has been undertaken by several researchers, complete 6-O-desulfation with little side reaction has not been attained successfully. In this work, a modified method with a certain silylating reagent, N-methyl-N-(trimethylsilyl)trifluoroacetamide, has been established to produce completely 6-O-desulfated heparin with few other chemical changes. The degrees of 6-O-desulfation were estimated by means of chemical disaccharide analyses and/or (13)C NMR spectra. Although the completely 6-O-desulfated heparin lost about 20% of 2-O-sulfate groups, any other chemical changes and depolymerization were not detected. The completely 6-O-desulfated heparin displayed strong inhibition of COS-1 cell adhesion to basic fibroblast growth factor (bFGF)-coated well in a dose-dependent manner, as was clarified by the competitive cell-adhesion assay. Furthermore, the completely 6-O-desulfated heparin was shown to promote in vitro A31 fibroblast proliferation in a dose-dependent manner in the presence of bFGF. These results suggest that signal transduction through bFGF/bFGF receptor in A31 cells occurs in the absence of 6-O-sulfate groups in heparin. The involvement of 6-O-sulfate group(s) of heparin/heparan sulfate in the promotion of bFGF mitogenic activity was reported by several groups. This discrepancy between our results and those of other groups would be due to the differences in molecular size of heparin/heparan sulfate derivatives and/or cell species used for the assay.

Animals↗
PubMed2000

Usefulness of mass screening for ovarian carcinoma using transvaginal ultrasonography.

BACKGROUND: International Federation of Gynecology and Obstetrics Stage I ovarian carcinoma, which has the worst prognosis among all types of gynecologic carcinoma, has a high cure rate as has been reported, but early diagnosis is difficult and to the authors' knowledge screening methods have not been established. Since 1989, the authors have performed transvaginal ultrasonography (TVS) as a form of screening for ovarian carcinoma. The purpose of the current study was to summarize and evaluate screening results for the last 10 years with respect to ovarian carcinoma diagnosis and risk factors. METHODS: Primary screening by TVS was performed in asymptomatic women who participated in annual uterine cervical carcinoma screening. Four scanning sections by TVS were established and all sonograms were recorded. Women with abnormal sonograms (a mass > 30 mm in greatest dimension or a mass with a mixed pattern) received secondary screening and closer examination with a tumor marker and an imaging diagnostic examination. Laparotomy was conducted on all masses with a greatest dimension of >/= 60 mm or on suspected malignant masses. Subject information-related risk factors also were recorded. RESULTS: Subjects were 183,034 women who participated in primary screening. Of these women, 51,550 were undergoing screening for the first time. The time required for primary screening was 1 minute per subject. Secondary screening was required for 5309 participants (10.3%) and surgery was performed on 324 participants. Twenty-two primary tumors and 2 metastatic tumors were detected for a diagnostic rate of 0.047%. Of the 22 primary tumors, 17 (77.3%) were classified as Stage I carcinoma, with tumor markers positive only for 5 (29.4%). The percentage of the total number of Stage I ovarian carcinoma cases increased after the induction of screening from 29.7% to 58.8%. CONCLUSIONS: These results are significant in that 77.3% of the primary ovarian carcinomas found during the current screening were of curable Stage I. Increased use of TVS screening for ovarian carcinoma may increase the chance for early diagnosis and decrease the mortality of the disease.

Adult↗
PubMed2000

Adenoviral vector-mediated GDNF gene transfer prevents death of adult facial motoneurons.

We examined neuroprotective effects of an adenoviral vector encoding glial cell line-derived neurotrophic factor (AxCAhGDNF) on the lesioned adult rat facial motoneurons. After facial nerve avulsion, animals locally injected into the facial canal with AxCALacZ (adenovirus encoding beta-galactosidase gene) or AxCAhGDNF showed expression of beta-galactosidase activity or intense immunolabeling for GDNF in lesioned facial motoneurons, respectively. The treatment with AxCAhGDNF after avulsion significantly prevented the loss of lesioned facial motoneurons, ameliorated choline acetyltransferase immunoreactivity, and suppressed the activity of nitric oxide synthase in these neurons. These results indicate that the adenovirus-mediated gene transfer of GDNF may prevent the degeneration of motoneurons in adult humans with peripheral nerve injury and motor neuron diseases.

Adenoviridae↗
PubMed2000

Direct observation of processive movement by individual myosin V molecules.

Myosin V is an unconventional myosin thought to move processively along actin filaments. To have hard evidence for the high processivity, we sought to observe directly the movement by individual native chick brain myosin V (BMV) molecules with fluorescent calmodulin. Single BMV molecules did exhibit highly processive movement along actin filaments fixed to a coverslip. BMV continued to move up to the barbed end of its actin track, and did not readily detach from action. The barbed end, therefore, got brighter with time, because of a constant stream of BMV traffic. The maximum speed of the processive movement was 1 microm/s, and the maximum actin-activated ATPase rate was 2.4 s(-1). These values apparently imply that BMV travels a great distance, 400 nm, per an ATPase cycle.

Actins↗
PubMed2000

Rescue of lesioned adult rat spinal motoneurons by adenoviral gene transfer of glial cell line-derived neurotrophic factor.

Glial cell line-derived neurotrophic factor (GDNF) has been shown to protect cranial and spinal motoneurons, that suggests potential uses of GDNF in the treatment of spinal cord injury and motor neuron diseases. We examined neuroprotective effect of human GDNF encoded by an adenovirus vector (AxCAhGDNF) on the death of lesioned adult rat spinal motoneurons. The seventh cervical segment (C7) ventral and dorsal roots and dorsal root ganglia of adult Fisher 344 rats were avulsed, and AxCAhGDNF, AxCALacZ (adenovirus encoding beta-galactosidase gene) or PBS was inoculated in C7 vertebral foramen. One week after the avulsion and treatment with AxCALacZ, the animals showed expression of beta-galactosidase activity in lesioned spinal motoneurons. Animals avulsed and treated with AxCAhGDNF showed intense immunolabeling for GDNF in lesioned spinal motoneurons and expression of virus-induced human GDNF mRNA transcripts in the lesioned spinal cord tissue. Nissl-stained cell counts revealed that the treatment with AxCAhGDNF significantly prevented the loss of lesioned ventral horn motoneurons 2 to 8 weeks after avulsion, as compared to AxCALacZ or PBS treatment. Furthermore, the AxCAhGDNF treatment ameliorated choline acetyltransferase immunoreactivity in the lesioned motoneurons after avulsion. These results indicate that the adenovirus-mediated gene transfer of GDNF may prevent the degeneration of motoneurons in adult humans with spinal cord injury and motor neuron diseases.

Adenoviridae↗
PubMed2000

Rapid morphological oscillation of mitochondrion-rich cell in estuarine mudskipper following salinity changes.

Morphological changes in the chloride cells or mitochondrion-rich (MR) cells in the skin under the pectoral fin of the estuarine mudskipper (Periophthalmus modestus) were examined in relation to intertidal salinity oscillation in river mouth. MR cells were distinguished between those in contact with the water (cells labeled with both mitochondrial probe DASPEI and Concanavalin-A, an apical surface marker of MR cells) and those that are not (DASPEI-positive only). After transfer of the fish from seawater to freshwater, no difference in the total MR cell density was observed, but the subpopulation of MR cells that are Concanavalin-A-positive decreased dramatically within 30 min. After 6 hr in freshwater, the fish were returned to seawater; the number of Con-A-positive MR cells increased to the initial levels rapidly. Thus, in seawater, mudskippers seem to open the apical crypts of the MR cells to secrete salt; in freshwater, they close the crypt of the MR cells tentatively, and tolerate hypotonicity until the rising tide. This unique response of chloride cells may also be seen in gills of other estuarine species.

Adaptation, Physiological↗
PubMed2000

Low dose propofol as a supplement to ketamine-based anesthesia during intraoperative monitoring of motor-evoked potentials.

STUDY DESIGN: Motor-evoked potentials (MEPs) were analyzed using transcranial electrical stimulation during spinal surgery in patients under ketamine-based anesthesia, with and without propofol. OBJECTIVE: To investigate the effects of propofol on MEPs and ketamine-induced adverse effects during spinal surgery in patients under ketamine-based anesthesia. SUMMARY OF BACKGROUND DATA: Intraoperative monitoring of transcranial motor-evoked responses provides a method for monitoring the functional integrity of descending motor pathways. However, because these responses are sensitive to suppression by most anesthetic agents, anesthetic technique is limited during the monitoring of MEPs. Ketamine has been reported to have little effect on MEPs but may produce adverse effects such as psychedelic effect and hypertension. Recently, it has been reported that propofol may be able to inhibit ketamine-induced adverse effects. METHODS: Intraoperative monitoring of MEPs was performed in 58 patients who underwent elective spinal surgery. Anesthesia was maintained with nitrous oxide-fentanyl-ketamine without or with low-dose (1-3 mg/kg/hr) of propofol (K group; n = 34, KP group; n = 24, respectively). Transcranial stimulation with single or paired pulses or a train of three or five pulses (interstimulus interval, 2 msec) were delivered to the scalp, and compound muscle action potentials were recorded from the left and right tibialis anterior muscles. To investigate the dose effects of propofol on MEPs, propofol was administered at an infusion rate of 6, 4, and 2 mg/kg/hr and then discontinued in 14 patients. RESULTS: Results of MEPs were comparable between the K and KP groups. The incidence of postoperative psychedelic effect was significantly less in the KP group (14%) than in the K group (41%). Although propofol inhibited MEPs dose dependently, the use of a train of pulses for stimulation could overcome such inhibition. CONCLUSIONS: If a train of pulses were used for transcranial stimulation, low-dose propofol can be effectivelyused as a supplement to ketamine-based anesthesia during intraoperative monitoring of myogenic MEPs. Addition of propofol significantly reduced the ketamine-induced psychedelic effects.

Adolescent↗
PubMed2000

Suppression of tumor angiogenesis and growth by gene transfer of a soluble form of vascular endothelial growth factor receptor into a remote organ.

Antiangiogenic therapy shows promise as a strategy for cancer treatment. We constructed an adenovirus (AdVEGF-ExR) expressing the entire extracellular domain of the human vascular endothelial growth factor (VEGF) receptor (flt-1) fused to the Fc portion of human IgG. The soluble receptor secreted from AdVEGF-ExR-infected cells bound to VEGF and inhibited VEGF-induced DNA synthesis in endothelial cells. When human lung cancer cell line H157, which produces not only VEGF but also fibroblast growth factor 2 and interleukin 8 at substantial levels, was infected with AdVEGF-ExR, cell growth in vitro was not affected. However, when H157 cells infected with AdVEGF-ExR were injected s.c. into nude mice, tumor formation stopped on the 10th day after reaching a certain size (about 100 mm3), and tumor size declined gradually thereafter. When AdVEGF-ExR was injected into skeletal muscle and uninfected H157 cells were injected s.c., the soluble receptor was detectable in the circulating blood for 3 weeks, tumor growth ceased after 10 days, and tumor size declined thereafter. Histological examination revealed that intratumor angiogenesis was markedly suppressed, and apoptosis was enhanced. Using the same experimental protocol, a significant suppression of tumor growth was also seen in four of five other lung cancer cell lines, some of which secreted VEGF at nominal levels, at least under normoxic conditions in vitro. Our results demonstrate that adenovirus-mediated expression of a soluble VEGF receptor in a remote organ could inhibit tumor angiogenesis and enhance apoptosis and thereby suppress tumor growth in vivo. Adenovirus-mediated overexpression of a soluble VEGF receptor in a remote organ may have the potential to be a feasible and effective strategy for cancer treatment.

Adenoviruses, Human↗