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T Nishimura

Publications and source records attributed to T Nishimura.

At least 325 records · Page 18Linked to original sources
PubMed1998

Application of real-time confocal microscopy for observation of living cells in tissue specimens.

Measurement of intracellular Ca2+ concentration ([Ca2+]i) has been a fundamental technique in cell biology. However, most investigations have used cultured or isolated cells as an experimental model, and consequently can provide only limited insight into the mechanisms that operate in tissue in situ. Useful information may be obtained by studying intact tissue specimens. High-speed confocal microscopes that can acquire digital images at video rate have recently been developed. These confocal microscopes which can acquire data in real-time enable [Ca2+]i dynamics of individual cells in intact tissue specimens to be observed. The present paper examines the use of fluorescent microscopy and confocal microscopy for [Ca2+]i imaging of living tissue. We analyzed the dynamics of the duodenal gland, lacrimal gland, intestinal smooth muscles, arterioles, myenteric plexus, and dorsal root ganglion. In these specimens, individual cells exhibited different [Ca2+]i dynamics, and the responses to transmitters/modulators were heterogeneous. In conclusion, real-time imaging provides a useful tool for observing dynamic changes in cells in situ, and it may lead to improve understanding tissue physiology.

Biological Transport↗
PubMed1998

[An operative case of primitive neuroectodermal tumor in the posterior mediastinum].

A primitive neuroectodermal tumor (PNET) is very rare and the prognosis of this tumor is poor. A 32-year-old woman complaining of dysphagia and back pain was admitted to our hospital for the posterior mediastinal tumor. The tumor originated from the muscle layer of esophagus and en bloc resection of the tumor combined with the affected part of esophagus was performed. Histopathological diagnosis of the resected tumor was PNET. She received adjuvant chemotherapy. Eight months after the surgery, recurrent tumors in the right mediastinum and the retrooperitoneal space was resected completely. But after the second surgery, dissemination occurred recurrently. These recurrent tumors revealed high sensitivity for radio-therapy. However, she died of rapid recurrence 22 months after the first surgery. In Japan, our case is the second case of PNET in the posterior mediastinum and the first case of PNET arising from the muscle layer of esophagus.

Adult↗
PubMed1998

Combined thallium-201 myocardial with technetium-99m-HMPAO brain SPECT: myocardial ischemia induced by acetazolamide in severe coronary artery disease.

Since the perioperative mortality of coronary artery bypass surgery is high in patients with cerebrovascular disease, it is crucial to assess a cerebrovascular risk before operation. Acetazolamide (ACZ) was applied to brain SPECT to evaluate the vascular reserve, and ACZ stress brain imaging was useful for predicting perioperative cerebrovascular events. We performed 201Tl myocardial and 99mTc-hexamethyl-propyleneamine oxime (HMPAO) brain SPECT with ACZ stress simultaneously to a patient with severe coronary artery disease and experienced the abnormality of 201Tl myocardial imaging with ACZ, as did that with dipyridamole. Technetium-99m-HMPAO brain SPECT showed no defect. Brain SPECT with ACZ demonstrated the region of poor coronary vascular reserve, which suggested myocardial ischemia induced by ACZ in a patient with severe coronary artery disease.

Acetazolamide↗
PubMed1998

[The relationship between the pathways of the lymphatic drainage into the mediastinal nodes and the survival rate for N2 lung cancers underwent curative resection].

The pathways of the metastases to the mediastinal nodes were determined in each case of 68 N2 lung cancer patients undergoing mediastinal lymph node dissection. The relationship between the pathways of the metastases and the survival rate was examined in the 57 N2 lung cancer patients undergoing curative resection. The results were as follows: (1) The direct metastatic passage to the mediastinal nodes was observed in 32.1% in the right upper lobe. The survival rate of this group was 55.4% (4-year survival rate), and that of cases metastasized to the intrapulmonary and/or hilar nodes as well as mediastinal nodes was 42.4% (3-year survival rate). (2) The dominant lymphatic drainage from the middle lobe and the lower lobes flowed into the subcarinal nodes through the hilar nodes. 75% had involvement of the subcarinal nodes, and 33.3% had involvement of the upper mediastinal nodes. 5-year survival rate of the cases without the upper mediastinal nodes metastases was 59.0%, and that of cases metastasized to the upper mediastinal nodes was 26.7% (3-year survival rate). (3) The dominant lymphatic drainage from the left upper lobe flowed into the subaortic or paraaortic nodes. 5-year survival rate in the left upper lobe was 50.0%. It suggested that the cases metastasized to the mediastinal nodes via the direct passage in the right upper lobe, the cases in the left upper lobe, and the cases metastasized to the subcarinal nodes without the upper mediastinal nodes metastases in the middle lobe and the lower lobes had better prognosis.

Humans↗
PubMed1998

[A case of pulmonary arteriovenous fistula beneath the surface of the lung].

A 19-year-old woman complaining of exertional dyspnea was admitted to our hospital with an abnormal shadow on the left side of the chest. Laboratory examination revealed polycythemia and hypoxemia. Pulmonary angiogram demonstrated a pulmonary arteriovenous fistula beneath the surface of the left S10. Partial resection of the left S10 was performed. The wall of the arteriovenous fistula was flimsy and seemed to rupture easily. The sister of this patient also had a peripheral pulmonary arteriovenous fistula and suffered from repeating epistaxis. Rendu-Osler-Weber disease was diagnosed in both, and the sister underwent partial resection of the right S7, which contained the fistula. Their postoperative courses were uneventful. Hemothorax and hemoptysis are lethal complications of arteriovenous fistulae. In order to avoid the rupture of fistulae, surgical resection is the most reliable treatment. Pulmonary arteriovenous fistulae beneath the surface of the lung should be resected.

Adolescent↗
PubMed1998

SPECT findings in mitochondrial encephalomyopathy.

UNLABELLED: We investigated the alterations in regional cerebral blood flow (rCBF) in mitochondrial encephalomyopathy (MEM), using [123I]N-isopropyl-p-iodoamphetamine (IMP) or 99mTc-hexamethyl propyleneamine oxime SPECT in 10 MEM patients. METHODS: Four of the patients had MEM with lactic acidosis and strokelike episodes (MELAS), 2 had Kearns-Sayre syndrome (KSS), 1 had myoclonic epilepsy with ragged red fibers (MERRF) and 3 had cytochrome C oxidase deficiency (CCOD). Cerebral perfusion reserve was obtained from 6 patients (3 MELAS, 1 MERRF, 1 KSS, 1 CCOD) for a comparative analysis using the split-dose 123I-IMP SPECT method before and after the injection of acetazolamide. RESULTS: All patients with MELAS showed focal hypoperfusion in the parietal and/or occipital lobes. Follow-up studies (3 MELAS patients) revealed extension or improvement in the abnormal perfusion. The hypoperfused lesions were correlated with abnormal CT/MRI findings. Perfusion was normal in 1 MERRF, 2 KSS and 3 CCOD patients, whereas CT/MRI findings in 1 MERRF, 1 KSS and 1 CCOD patient were abnormal. The cerebral perfusion reserve in 3 MELAS patients was decreased significantly compared with that in patients with other types of MEM (MELAS 7.4%, other MEM 33.8%; p < 0.05). CONCLUSION: The rCBF was altered specifically in patients with MELAS, suggesting that brain perfusion SPECT will be useful in diagnosing and assessing such patients. The decreased cerebral perfusion reserve in patients with MELAS may represent an important feature of the pathogenesis of the strokelike episodes. The SPECT findings of patients with other types of MEM (MERRF, KSS and CCOD) were normal.

Adolescent↗
PubMed1998

[Identification of aneuploids in uncultured amniotic fluid cells by interphase fluorescence in situ hybridization].

We report the diagnosis of aneuploids in uncultured amniotic fluid cells by the use of interphase fluorescence in situ hybridization (FISH). About a dozen of cases was studied to detect chromosome aneuploids (trisomies 13, 18 and 21, and monosomy X), especially those in the perinatal period. Results of FISH experiments in each specimen were compared with those of conventional chromosome analysis, and showed no discrepancy between them in most cases. FISH analysis revealed that four 18-trisomies had two different cells, one of which showed two fluorescence signals and the other three signals, the result indicating a maternal cell contamination. Thus, special attention should be paid when FISH analysis is adopted to the diagnosis in uncultured amniotic fluid cells in order to avoid misdiagnosis that may originate in maternal cell contamination.

Amniotic Fluid↗
PubMed1998

Basic and clinical studies on the measurement of tau protein in cerebrospinal fluid as a biological marker for Alzheimer's disease and related disorders: multicenter study in Japan.

The development of a diagnostic marker for earlier and more accurate clinical diagnosis of Alzheimer's disease (AD) is essential to identify AD patients during life unequivocally. The purpose of this study was to investigate the basic performance and clinical significance of tau level measurement in the cerebrospinal fluid (CSF) using an enzyme-linked immunosorbent assay (ELISA) developed by Innogenetics. The ELISA system showed reliable reproducibility and good linearity. For clinical studies, the CSF samples from a variety of patients (n = 332) were examined. They were classified into the four groups: Alzheimer's disease (AD); neurodegenerative disease (ND); cerebrovascular diseases (VD); and a neurological control (NC) group. The CSF-tau levels for AD, ND, VD and NC were 426 +/- 234 pg/ml, 239 +/- 157 pg/ml, 216 +/- 136 pg/ml, and 188 +/- 103 pg/ml, respectively. The CSF-tau level of the AD group was significantly higher than that of the other groups (p < 0.001). The CSF-tau levels increased during follow-up. The measurement of the tau level in CSF is shown to be a useful marker to confirm a clinical diagnosis of AD.

Aged↗
PubMed1998

[A comparison of a 3 day course with a 2 week course of oral prednisolone in patients with chronic asthma].

To investigate an appropriate duration of short course of a oral prednisolone (PSL), we compare the results of a 3 day course of PSL (3D) with those of a 2 week course of PSL (2W) in 20 patients with chronic asthma. All subjects had been inhaling beclomethasone dipropionate (BDP, mean daily dose: 1325 micrograms), and had been self-monitoring their peak expiratory flow rate (PEF) for at least 6 months. Mean +/- SE of the best PSL-induced PEF in 2W (2W-best) was not different from that in 3D (397 +/- 29 and 356 +/- 23 L/min, respectively, p = 0.26). Mean weekly morning PEF/2W-best before and 1, 2, 3 and 4 weeks after PSL was 60, 76, 80, 76 and 76% in 2W, and 63, 73, 67, 67 and 65% in 3D, respectively. Both changes over the course of time were significant. The frequency of emergency room visits and/or unscheduled hospital visits was not significantly different between 2W and 3D. However, both the frequency of use of inhaled beta 2 agonists and the symptom score significantly decreased only in 2W. Seven patients (35%) did not need additional oral PSL during the 4-week period after initiating 3D, and among these patients, emergency room visits and/or unscheduled hospital visits were completely controlled. In conclusion, although the effect of 3D was inferior than that of 2W, it was a sufficient duration in 35% of the patients, and thus, may be appropriate as a initial duration of rescue course of oral steroids.

Administration, Oral↗
PubMed1998

[Two cases of solitary peripheral pulmonary arterial aneurysm].

We report two very rare cases of solitary peripheral pulmonary arterial aneurysm. Case 1: An 83-year-old man treated for myocardial infarction died of multiple organ failure and hemoptysis. Autopsy disclosed rupture of a pulmonary arterial aneurysm 1.5 cm in diameter in the right A3. Case 2: A 75-year-old man was found to have a pulmonary arterial aneurysm, 3 cm in diameter of the right A1. Surgical treatment was not indicated, because of severe pulmonary emphysema. The aneurysms in these two cases were idiopathic: (1) there were no histologic findings that would implicate specific chronic inflammation. (2) the period from the occurrence of secondary pulmonary hypertension to hemoptysis was short, and there was no (3) history of trauma.

Aged↗
PubMed1998

Iodine-123-iomazenil and iodine-123-iodoamphetamine SPECT in major cerebral artery occlusive disease.

UNLABELLED: Iodine-123-iomazenil (IMZ) is a SPECT ligand for central-type benzodiazepine receptors, which are located only on neurons. We evaluated the feasibility of using IMZ SPECT for identifying neuronal damage in patients with the chronic phase of thrombotic cerebral ischemia. METHODS: We studied 15 patients with angiographically-confirmed unilateral severe occlusive lesions (occlusion or > 70% stenosis) in the carotid system. IMZ SPECT images obtained 180 min after injection of 167-222 MBq IMZ were analyzed. The regional cerebral blood flow and perfusion reserve were evaluated for comparison with IMZ SPECT findings, using the split-dose 123I-iodoamphetamine (IMP) SPECT method, coupled with intravenous injection of 1 g acetazolamide. On both SPECT images, the count ratio of the affected to the nonaffected whole MCA territory (A/NA ratio) and of the contralateral to the ipsilateral cerebellar cortex (C/I ratio) were determined. RESULTS: The A/NA ratio with IMZ was significantly higher than that with IMP (94.5% +/- 6.2% versus 91.4% +/- 6.6%, p < 0.005), although a significantly positive correlation was found between these two ratios (r = 0.854, p < 0.0001). The C/I ratio with IMP was decreased significantly in 5 patients compared with that in normal subjects, whereas the C/I ratio with IMZ was decreased in only 1 patient. There was no significant correlation between the A/NA ratio with IMZ and the perfusion reserve in the affected MCA territory. In 2 of 5 patients with a decreased A/NA ratio (<90%) with IMZ, decreased blood flow with preserved perfusion reserve and cerebral hemispheric atrophy were observed, which suggested the influence of neuronal loss due to chronic ischemia. CONCLUSION: These findings indicate that IMZ SPECT, which provides new information regarding neuronal damage after ischemic insult to the brain, is useful for evaluating thrombotic cerebral ischemia.

Amphetamines↗
PubMed1998

Surgical outcome on combined procedures of lens extraction, intraocular lens implantation, and vitrectomy during removal of the epiretinal membrane.

BACKGROUND AND OBJECTIVE: The authors evaluated the outcome of combined procedures of lens extraction, intraocular lens implantation, and vitrectomy during procedures for the removal of the epiretinal membrane, and attempt to clarify which factors affected the outcome of surgery. PATIENTS AND METHODS: Surgery for the removal of the epiretinal membrane was performed and a 2-year follow-up program was maintained for 32 eyes at the authors' clinic during the past 5 years. The combined procedure was undertaken in 15 eyes, whereas a simple vitrectomy was performed in 17 eyes. Results were analyzed by postoperative ophthalmoscopic and slit-lamp examinations for visual acuity and complications. RESULTS: Six months after surgery, visual acuity improved similarly in both groups. But, 2 years after surgery, 11 eyes (65%) that underwent a simple vitrectomy showed decreased visual acuity due to the advancement of cataracts. The postoperative visual acuity at 6 months correlated to preoperative visual acuity, and the advancement of cataracts tended to correlate inversely to the age of the patients. Major complications did not occur in any of the cases. CONCLUSION: Earlier surgical management is better for treatment of the epiretinal membrane, and a combined procedure has advantages in cost reduction and is less troublesome, especially for elderly patients.

Adult↗
PubMed1998

Fluorine-18-fluorodeoxyglucose PET identification of cardiac metastasis arising from uterine cervical carcinoma.

Cardiac metastasis of uterine cervical carcinoma is rare. We describe a patient with a past history of uterine cervical carcinoma who presented with metastasis to the heart, lungs and distant lymph nodes 3 yr after surgery and chemotherapy. Since the patient complained of chest pain and demonstrated electrocardiogram abnormalities, we performed echocardiography, electron beam CT and MRI, which revealed a tumor in the right ventricular wall. The tumor was assessed by 67Ga scintigraphy and 18F-fluorodeoxyglucose (FDG) PET scanning. The mean differential 18F-FDG uptake ratio of the tumor was 7.9, suggesting malignancy, which was later confirmed by myocardial biopsy. Information about the extent of the tumor and partial necrosis within it was provided by 18F-FDG PET. Although both radionuclide imaging techniques also detected metastatic lesions in the lungs and lymph nodes, 18F-FDG PET scanning detected small lesions more sensitively than 67Ga scintigraphy.

Adult↗
PubMed1998

[Evaluation of clinical utility of 99mTc-MIBI scintigraphy in the localization of thyroid, breast and lung/mediastinum tumors--a report of multicenter phase III clinical trials].

Phase III clinical study in 136 patients diagnosed or strongly suspected of thyroid, lung/mediastinum or breast cancer was performed to determine clinical utility of 99mTc-MIBI in the localization of tumors, and the results in 135 were evaluated. Except taste peculiar in 43 patients and nausea in one, no adverse events were reported. Seven abnormal changes in vital signs and 27 in clinical laboratories were noted, which were all judged as having no or unlikely relationship to the agent. Out of 177 malignant lesions, 156 (88%) were detected with 99mTc-MIBI regardless of their histology or location. Of 6 benign tumors, 3 were detected. Fifteen sites of false positive in 11 malignant tumor patients and 5 sites in 6 patients with non-tumor disease were observed. Our study indicates that 99mTc-MIBI is a safe and excellent agent for the localization of tumors. Especially, the fact that 99mTc-MIBI detected remote metastatic lesions with high sensitivity is a great advantage over the other conventional imaging modalities.

Adult↗
PubMed1997

Manipulation of Th1/Th2 balance in vivo by adoptive transfer of antigen-specific Th1 or Th2 cells.

We have investigated the possibility that the Th1/Th2 balance in vivo may be modulated by adoptive transfer of Th1 or Th2 cells induced in vitro. Thl cells were induced from I-Ad-binding OVA323-339-specific T-cell receptor-transgenic (TCR-Tg) mouse spleen cells by culturing with OVA323-339 peptide and antigen presenting cells (APC) in the presence of IL-2, IL-12 and anti-IL-4 mAb. Th2 cells were induced from TCR-Tg mouse spleen cells by culturing with IL-2, IL-4 and anti-IL-12 mAb in addition to OVA323-339 plus APC. Immunomodulating activities of both Th1 and Th2 cells were determined by their effect on delayed type hypersensitivity (DTH) responses or cytokine production. No significant DTH responses (footpad swelling) were observed in untreated BALB/c mice following a single injection of OVA323-339-pulsed syngeneic spleen cells. However, adoptive transfer of Th1 cells into BALB/c mice induced strong dose dependent DTH responses in response to I-Ad-bound OVA323-339 but not unrelated peptide. In contrast, only slight DTH responses were detected in BALB/c mice transferred with Th2 cells. In parallel with the DTH responses, increased levels of serum IFN-gamma were demonstrated in mice adoptively transferred with Th1, while no significant increase was observed in Th2-transferred mice. In vitro analysis also demonstrated that both spleen cells and popliteal lymph node cells prepared from Th1-transferred mice showed Th1-type cytokine production, while cells obtained from Th2-transferred mice revealed Th2-dominant cytokine production. Such immune deviation induced by antigen-specific Th1 cells was demonstrated up to three months after cell transfer. Therefore, it may be possible to manipulate the Th1/Th2 balance in vivo by adoptive transfer of antigen-specific Th1 or Th2 cells.

Adoptive Transfer↗
PubMed1997

Actions of barium on rapidly inactivating potassium current in bullfrog sympathetic neurons.

Whole-cell/voltage-clamp recordings were made from dissociated bullfrog sympathetic neurons to examine the inhibitory actions of barium (0.01-3 mM) on a rapidly inactivating A-type potassium current (IA). The IC50 value was about 0.9 mM. Barium (1 mM) approximately halved the maximum amplitude of IA (approximately 1.7 nA near 0 mV) without significantly affecting a voltage for the 50%-activation (approximately -40 mV) and that for the 50%-inactivation (approximately -90 mV), nor did it affected the time course of IA. The results suggest that the barium block is independent of the kinetics of the A-channels in bullfrog sympathetic neurons.

Animals↗
PubMed1997

Screening of fungal beta-xylanases for production of acidic xylooligosaccharides using in situ reduced 4-O-methylglucuronoxylan as substrate.

Fungal beta xylanases were screened for production of acidic xylooligomers from 4-O-methylglucuronoxylan. In situ reduced hardwood xylan was used as substrate because the products of neutral- and acidic-branched xylooligomers help define substrate specificity of the enzymes. Borohydride reduction in situ transformed 30% of 4-O-methyl-alpha-D-glucopyranosyluronic acid residues into 4-O-methyl-alpha-D-glucopyranosyl residues and reduced C-1 end groups in the xylan backbones. A total of ten beta-xylanase fractions from four fungi were partially purified by chromatography by anion exchange and molecular sieving, and graded qualitatively for enzymatic hydrolysis of the substrate. The yield of acidic xylooligomers was highly affected by whether alpha-glucuronidases were present in the beta-xylanase fractions. Some fractions gave free 4-O-methyl-alpha-D-glucopyranosyluronic acid, but none of the enzyme fractions could release free 4-O-methyl-alpha-D-glucose. Among the beta-xylanase fractions studied, xylanase II of Trichoderma viride was the best producer of aldotetraouronic acid [2-O-(4-O-methyl-alpha-D-glucopyranosyluronic acid)-D-xylotriose]. The results obtained suggested that there was a difference in the steric hindrance of the branch point on fungal beta-xylanases between 4-O-methyl-alpha-D-glucopyranosyl and 4-O-alpha-D-glucopyranosyluronic acid residues.

Basidiomycota↗