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N Tomiyama

Publications and source records attributed to N Tomiyama.

At least 37 records · Page 2Linked to original sources
PubMed1999

Acute interstitial pneumonia: thin-section CT findings in 36 patients.

PURPOSE: To characterize the computed tomographic (CT) findings of acute interstitial pneumonia and to correlate the pattern and the extent of abnormalities with the time between symptom onset and CT. MATERIALS AND METHODS: The study included 36 patients (20 men, 16 women; age range, 22-83 years; mean age, 61 years) with histopathologically proved acute interstitial pneumonia who were identified retrospectively. The time between symptom onset and CT was 2-90 days (mean, 22 days; median, 17 days). The presence, extent, and distribution of various CT findings were evaluated. Disease duration and extent of each finding were compared by using the Spearman rank correlation coefficient. RESULTS: Areas with ground-glass attenuation, traction bronchiectasis, and architectural distortion were present in all 36 patients. Airspace consolidation was present in 33 patients (92%). The extent of areas of ground-glass attenuation (r = 0.45, P < .01) and the extent of traction bronchiectasis (r = 0.35, P < .05) correlated with disease duration. No other significant correlation was found between the CT findings and disease duration. CONCLUSION: A combination of ground-glass attenuation, airspace consolidation, traction bronchiectasis, and architectural distortion is seen in the majority of patients with acute interstitial pneumonia. The extent of ground-glass attenuation and traction bronchiectasis increases with disease duration.

Acute Disease↗
PubMed1999

In vitro characteristics and in vivo plasma disposition of cisplatin conjugated with oxidized and dicarboxymethylated dextrans.

In vitro release behavior and cytotoxic activity, and in vivo plasma disposition of newly synthesized macromolecular derivatives of cisplatin (CDDP) were investigated and compared with CDDP. The derivatives included oxidized dextran conjugate of CDDP (OX-Dex/CDDP) and dicarboxymethylated dextran conjugate of CDDP (DCM-Dex/CDDP). In vitro release of platinum complex from dextran conjugated CDDP was determined by an equilibrium dialysis method. These dextran conjugates showed sustained release of the platinum complex. In vitro release half-life for DCM-Dex/CDDP was significantly longer (4.5 times) than that for OX-Dex/CDDP. In vitro cytotoxic activity of CDDP and dextran conjugated CDDP against colon 26, mouse colon cancer cell line, was measured using the MTT assay method. OX-Dex/CDDP showed a similar cytotoxic activity to CDDP. However, both cytotoxic activities were markedly decreased when preincubated with the medium containing serum. On the other hand, DCM-Dex/CDDP retained residual cytotoxic activity at a significantly higher level than OX-Dex/CDDP after preincubation with the medium containing serum, although it showed the lowest cytotoxic activity. This indicated longer maintenance of the in vitro antitumor activity of DCM-Dex/CDDP in serum compared with OX-Dex/CDDP. Plasma disposition of CDDP and dextran conjugated CDDP was determined by intravenous administration to rats. Although the total platinum plasma concentration-time profile for OX-Dex/CDDP was similar to that for CDDP, its markedly higher profile was achieved when DCM-Dex/CDDP was administered. The values of the total platinum AUC and MRT, where AUC is the area under the platinum concentration-time curve and MRT is the mean residence time, for DCM-Dex/CDDP were 11.2 times and 4.8 times significantly higher than with OX-Dex/CDDP in plasma, respectively. DCM-Dex/CDDP also showed a significantly lower total clearance compared with OX-Dex/CDDP. These results from the in vivo experiments revealed that retention of DCM-Dex/CDDP in blood circulation was much greater than that for OX-Dex/CDDP. DCM-Dex/CDDP thus has potential as a macromolecular derivative of CDDP for passive tumor targeting.

Animals↗
PubMed1999

Differential diagnosis of lymphocytic interstitial pneumonia and malignant lymphoma on high-resolution CT.

OBJECTIVE: Lymphoproliferative disorders span a spectrum from inflammatory lesions to malignant neoplasms. The purpose of this study was to compare high-resolution CT findings of lymphocytic interstitial pneumonia with those of malignant lymphoma of the chest. MATERIALS AND METHODS: The study included 17 patients with lymphocytic interstitial pneumonia and 44 patients with malignant lymphoma (35 with non-Hodgkin's lymphoma and nine with Hodgkin's disease). Without knowledge of the pathologic diagnosis, two chest radiologists evaluated the frequency and distribution of high-resolution CT findings in both groups of patients. RESULTS: Cysts were more common in patients with lymphocytic interstitial pneumonia (14/17, 82%) than in patients with malignant lymphoma (1/44, 2%) (p < .0001). Air-space consolidation was more commonly seen in patients with malignant lymphoma (29/44, 66%) than in patients with lymphocytic interstitial pneumonia (3/17, 18%) (p < .001). Large nodules (11-30 mm in diameter) were more common in patients with malignant lymphoma (41%) than in patients with lymphocytic interstitial pneumonia (6%). Pleural effusions (25%) were seen only in patients with malignant lymphoma. We found no statistically significant difference in the distribution of lung lesions between patients with lymphocytic interstitial pneumonia and patients with malignant lymphoma. CONCLUSION: On high-resolution CT, cysts are characteristic in patients with lymphocytic interstitial pneumonia, whereas consolidation, large nodules, and pleural effusions are characteristic in patients with malignant lymphoma. These findings on high-resolution CT help differentiate lymphocytic interstitial pneumonia from malignant lymphoma.

Adult↗
PubMed1999

[Mood congruency and incongruency effects on sentence writing].

This study investigated the influence of positive and negative moods on sentence writing. Short animated video clips, inducing either a positive or negative mood, were shown to 60 female undergraduates. Then, they wrote five sentences under one of two conditions: the sentences were to begin with "I" or "M" (a third person) as the subject. Main results were as follows: with the first person pronoun as the subject, the negative mood group showed a mood-congruency effect for the first sentence, and a mood-incongruency effect for the second to fifth sentence, with "M" as the sentence subject, the negative mood group showed a mood-incongruency effect for all the five sentences. The positive mood group showed a mood-congruency effect for all the sentences, regardless of "I" or "M" condition. Furthermore, under "I" condition, the students in the negative mood group reported their desire to change their mood. It is concluded that mood-incongruency effect on writing depended on the subject of the sentence.

Adult↗
PubMed1999

Feasibility of fluorodeoxyglucose dual-head gamma camera coincidence imaging in the evaluation of lung cancer: comparison with FDG PET.

UNLABELLED: The purpose of this study was to elucidate the feasibility of fluorodeoxyglucose gamma camera coincidence imaging (FDG GCI) in the evaluation of lung cancer in comparison with FDG PET. METHODS: Twenty-three patients with recently diagnosed lung cancer were examined with both FDG PET and FDG GCI on the same day. Pulmonary lesions were analyzed visually and semiquantitatively using the ratio of lesion-to-background counts (L/B ratio). The L/B ratio of FDG PET without attenuation correction (AC) was also calculated and compared. Nodal stations were only visually analyzed. RESULTS: FDG GCI and FDG PET could detect 22 and 23, respectively, of 23 pulmonary lesions by visual analysis (95.7% versus 100%). The L/B ratio of FDG GCI was 4.26 +/- 2.55, and significantly lower than that of FDG PET (9.29 +/- 4.95; P < 0.01). The L/B ratio of FDG PET was significantly higher with AC than that without AC (9.29 +/- 4.95 vs. 6.66 +/- 4.65; P < 0.01). When the L/B ratio threshold was set at 5.0 for FDG PET and 2.7 for FDG GCI, their sensitivity was 87.0% and 73.9%, respectively. Of the 3 and 6 patients with false-negative results on semiquantitative analysis, the lesions in 3 patients on FDG PET and 4 patients on FDG GCI were less than or equal to 2.0 cm in greatest diameter, respectively. In the assessment of mediastinal involvement, FDG PET was 77.8% sensitive, 78.6% specific and 78.3% accurate, whereas FDG GCI was 77.8% sensitive, 92.9% specific and 87.0% accurate. In the hilar regions, FDG PET was 100% sensitive, 84.2% specific and 87.0% accurate, whereas FDG GCI was 75.0% sensitive, 89.5% specific and 87.0% accurate. CONCLUSION: In this study, FDG GCI yielded results comparable to FDG PET on visual analysis to detect pulmonary lesions and lymph node metastases. However, the lesion-to-background contrasts of pulmonary lesions and nodal involvement were lower in FDG GCI than in FDG PET. Comparison between the L/B ratio of FDG PET with and without AC indicated that, with AC, FDG GCI would be closer to FDG PET in the evaluation of lung cancer.

Adenocarcinoma↗
PubMed1999

[Usefulness of helical scanning CT in assessment of left ventricular papillary muscle contractility].

Three-dimensional data on the left ventricle at quasi-end-diastole and quasi-end-systole were acquired by helical scanning CT in 12 patients. Short axial images of the left ventricle and long axial images of the papillary muscle were created using multiplanar reconstruction. Left ventricular dimensions and the length of the papillary muscle were measured, and fractional shortening of the papillary muscle was calculated. There was a good correlation between left ventricular dimensions measured by echocardiogram and helical scanning CT (end-diastole: r = 0.94: end-systole: r = 0.86; fractional shortening of left ventricular dimension: r = 0.84). Papillary muscle fractional shortening was 6.3% in the ischemic group and 21.5% in the non-ischemic group (p < 0.005). Helical scanning CT is clinically useful for the assessment of left ventricular papillary muscle function.

Adult↗
PubMed1999

[Total intravenous anesthesia with propofol, fentanyl and ketamine for carotid endarterectomy under somatosensory evoked potential monitoring--combination with intraoperative hypothermia].

We reported anesthetic management combined with hypothermia for carotid endarterectomy under somatosensory evoked potential monitoring. Anesthesia was induced by propofol, fentanyl and ketamine, and maintained by infusion of propofol and ketamine and intermittent injections of fentanyl. Perioperative hypothermia was induced by gradually reducing the temperature of a circulating water mattress underneath the body to 15 degrees C. Additionally, somatosensory evoked potential monitoring was performed and recordings were obtained immediately after induction of anesthesia, and before as well as during cross-clamping of the internal carotid artery. Rectal temperature was reduced to 33.7 degrees C when cross-clamping of carotid artery was carried out, but major changes between before and during the procedure was not observed. All procedures were done uneventfully and gradual rewarming was accomplished by electric blanket. No neurological deficits were observed following recovery from anesthesia. Total intravenous anesthesia with propofol, fentanyl and ketamine may be useful for carotid endarterectomy under hypothermia and somatosensory evoked potential monitoring. This method may provide neuronal protection against ischemia injuries induced by cross-clamping of the carotid artery.

Aged↗
PubMed1998

Intrathoracic multicentric Castleman disease: CT findings in 12 patients.

PURPOSE: To assess the computed tomographic (CT) findings of intrathoracic involvement in multicentric Castleman disease. MATERIALS AND METHODS: The study comprised 12 patients with lymph node biopsy-proved Castleman disease and multicentric involvement. The patients were aged 23-58 years (mean age, 42.9 years; five men, seven women). Seven patients underwent open lung biopsy (n = 3) or transbronchial lung biopsy (n = 4), which demonstrated lymphocytic interstitial pneumonitis. RESULTS: All patients had systemic symptoms, polyclonal hypergammaglobulinemia, and bilateral hilar and mediastinal lymph node enlargement. The nodes showed mild to moderate enhancement after intravenous administration of contrast material. At thin-section CT, all 12 patients showed poorly defined centrilobular nodules. Thin-walled cysts were present in 10 patients, thickening of the bronchovascular bundles in 10, and interlobular septal thickening in nine. Less common findings were subpleural nodules, ground-glass attenuation, air-space consolidation, and bronchiectasis. CONCLUSION: Multicentric Castleman disease is characterized by the presence of systemic symptoms, bilateral hilar and mediastinal lymphadenopathy, and centrilobular nodular opacities. The pulmonary parenchymal findings are due to the associated lymphocytic interstitial pneumonitis.

Adult↗
PubMed1997

In-vivo microdialysis study of the distribution of cisplatin into brain tumour tissue after intracarotid infusion in rats with 9L malignant glioma.

Simultaneous brain microdialysis in tumour and non-tumour tissues has been used for kinetic determination of the local distribution of an anticancer agent, cisplatin, in rats. Rat brain was implanted with 9L malignant glioma and cisplatin (3.5 mg kg-1) was administered as a selective intracarotid infusion for 30 min to rats prepared for brain microdialysis. The amount of platinum in the dialysate collected from tumour and non-tumour brain tissues was determined by atomic absorption spectrophotometry, as representative of cisplatin. Total and free platinum concentrations in plasma were also measured. Free platinum is accumulated preferentially in the tumour tissue and the brain tumour distribution coefficient (the ratio of brain tumour platinum AUC to plasma free platinum AUC, where AUC is the area under the platinum concentration-time curve) was 0.69, although there was little distribution into normal brain tissue. Drug binding to plasma proteins was 65%. It is concluded that simultaneous microdialysis is an easy and available method for assessing in-vivo local pharmacokinetics and distribution of cisplatin in tumour and non-tumour tissues of the brain.

Animals↗
PubMed1997

Characteristics of neurons with high-frequency discharge in the central nervous system and their relationship to chronic pain. Experimental and clinical investigations.

High-frequency extracellular unitary activity was recorded mainly in the ventral caudal nucleus of the thalamus in chronic-pain patients. These high-frequency discharge (hyperactive) neurons shows three types of discharge pattern with different interval histograms. Some of these hyperactive neurons were suppressed by the administration of a calcium antagonist (nicardipine). In an experimental study, chronic-pain models were made in rats according to the method of Lombard et al. (1979). From these animals, hyperactive neurons were recorded from the contralateral thalamic nuclei, lemniscus medialis. Hyperactive neurons were examined via electrical stimulation of and/or iontophoretic application. The results suggest that there is some relationship to the glutamatergic and GABAergic (probably GABAA) fibers or receptors.

Animals↗
PubMed1996

Modified petrosal approach using cosmetic osteoplastic craniotomy with NEURO-SAT guidance.

The petrosal approach has become a routine procedure for petroclival lesions, but there are some disadvantages such as the time-consuming craniotomy during surgery and depressed deformity of the mastoid area after surgery. To solve these disadvantages, we modified the petrosal approach. Before surgery, the three-dimensional points of the sigmoid sinus and semicircular canals are calculated on computed tomography scan and are input to a computer. A single temporooccipital bone flap is made, and the outer table of bone overlying the mastoid is preserved by forming a narrow groove with a small air drill and cutting the outer table with a chisel. After removing these two free bone flaps, mastoidectomy is performed guided by NEURO-SAT (neuronavigation by computer-assisted frameless stereotaxy). The mastoid bone can be drilled out safely and quickly. The two bone flaps are connected and replaced at the end of the procedure. Osteoplastic petrosal craniotomy guided by NEURO-SAT can achieve a quick craniotomy and satisfactory cosmetic result.

Abducens Nerve↗
PubMed1996

Detection of subtle interstitial abnormalities of the lungs on digitized chest radiographs: acceptable data compression ratios.

OBJECTIVE: To determine acceptable compression ratios for digital radiography, we evaluated the effect of data compression on the detection of subtle interstitial lung abnormalities using digitized chest radiographs. MATERIALS AND METHODS: Screen-film chest radiographs of 38 patients with subtle interstitial lung abnormalities and 40 patients with normal lung parenchyma were digitized (spatial resolution, 0.175 mm; 2000 x 2000 pixels; 10 bits per pixel) and compressed with the discrete cosine transform method at ratios of 10:1, 20:1, and 30:1. Five chest radiologists and five radiology residents examined the uncompressed and compressed digital images and rates the presence of interstitial lung abnormalities with a five-level scale of confidence. Results were analyzed by receiver operating characteristic methods. RESULTS: Overall, the interpretation of images with a compression ratio of 30:1 was significantly less accurate than that of uncompressed images (p < .05). For the five chest radiologists, interpretation of images with a compression ratio of 20:1 or 30:1 was significantly less accurate than that of uncompressed images (p < .05). However, for the five residents, no significant difference between interpretations of compressed and uncompressed images was noted (p > or = .05). CONCLUSION: These results suggest that a 10:1 data compression ratio does not influence the detection of subtle interstitial lung abnormalities. However, information that is lost with a 20:1 data compression ratio might be essential for interpretation by experienced chest radiologists.

Adult↗
PubMed1996

[A successfully operated case of tuberous sclerosis presenting with intractable epilepsy].

A 20-year-old male patient with tuberous sclerosis was admitted to our hospital complaining of intractable epilepsy. He had been suffering from frequent seizures despite anticonvulsant treatment since the age of 1 year. CT scan and magnetic resonance images showed multiple calcified lesions at the paraventricle and temporal lobe on both sides. Electroencephalogram showed left temporal lobe dominant spike waves. After deep electrodes were inserted into the left amygdala and hippocampus and subdural electrodes were placed on the left temporal cortex, clinical seizures were monitored by video and EEG. The primary focus was found in the amygdala. Left temporal lobectomy was carried out through the cranio-orbital zygomatic approach. Postoperatively, the patient has been seizure-free for one year. Despite multiple intracerebral lesions in tuberous sclerosis, resection of the primary epileptogenic focus is needed to solve the seizure problem if the focus is localized.

Adult↗
PubMed1995

Cloning and nucleotide sequencing of the membrane-bound L-sorbosone dehydrogenase gene of Acetobacter liquefaciens IFO 12258 and its expression in Gluconobacter oxydans.

Cloning and expression of the gene encoding Acetobacter liquefaciens IFO 12258 membrane-bound L-sorbosone dehydrogenase (SNDH) were studied. A genomic library of A. liquefaciens IFO 12258 was constructed with the mobilizable cosmid vector pVK102 (mob+) in Escherichia coli S17-1 (Tra+). The library was transferred by conjugal mating into Gluconobacter oxydans OX4, a mutant of G. oxydans IFO 3293 that accumulates L-sorbosone in the presence of L-sorbose. The transconjugants were screened for SNDH activity by performing a direct expression assay. One clone harboring plasmid p7A6 converted L-sorbosone to 2-keto-L-gulonic acid (2KGA) more rapidly than its host did and also converted L-sorbose to 2KGA with no accumulation of L-sorbosone. The insert (25 kb) of p7A6 was shortened to a 3.1-kb fragment, in which one open reading frame (1,347 bp) was found and was shown to encode a polypeptide with a molecular weight of 48,222. The SNDH gene was introduced into the 2KGA-producing strain G. oxydans IFO 3293 and its derivatives, which contained membrane-bound L-sorbose dehydrogenase. The cloned SNDH was correctly located in the membrane of the host. The membrane fraction of the clone exhibited almost stoichiometric formation of 2KGA from L-sorbosone and L-sorbose. Resting cells of the clones produced 2KGA very efficiently from L-sorbosone and L-sorbose, but not from D-sorbitol; the conversion yield from L-sorbosone was improved from approximately 25 to 83%, whereas the yield from L-sorbose was increased from 68 to 81%. Under fermentation conditions, cloning did not obviously improve the yield of 2KGA from L-sorbose.

Acetobacter↗
PubMed1995

Cloning and Nucleotide Sequencing of the Membrane-Bound l-Sorbosone Dehydrogenase Gene of Acetobacter liquefaciens IFO 12258 and Its Expression in Gluconobacter oxydans.

Volume 61, no. 2, p. 419, column 1, lines 15-19: this sentence should read as follows. "The alcohol dehydrogenase and glucose dehydrogenase have a common region reported to be related to pyrroloquinoline quinone binding (2, 10), but SNDH does not contain such a region, indicating that SNDH is not a quinoprotein." Page 419, column 2, line 12: "(Table 4)" should read "(Table 3)." [This corrects the article on p. 413 in vol. 61.].

Journal Article↗
PubMed1995

Hashimoto thyroiditis: correlation of MR imaging signal intensity with histopathologic findings and thyroid function test results.

PURPOSE: To assess the clinical usefulness of magnetic resonance (MR) imaging of the thyroid gland in Hashimoto thyroiditis. MATERIALS AND METHODS: Signal intensity ratios on spin-echo T1-, proton-density-, and T2-weighted images were measured prospectively in 37 patients with Hashimoto thyroiditis (33 women, four men; mean age, 51 years) and in 10 patients with thyroid lymphoma (six women, four men; mean age, 68 years). Signal intensity ratios were correlated with histopathologic findings and thyroid function test results with stepwise regression analysis. Diagnosis of lymphoma with signal intensity ratios was compared with morphologic diagnosis by using receiver operating characteristic curves. RESULTS: A proton-density-weighted signal intensity ratio of 1.54 or higher indicated hypothyroidism (R = .445, P = .008; 29% sensitivity [two of seven patients]). A T2-weighted signal intensity ratio of 5.08 or higher suggested advanced glandular destruction (R = .677, P < .001). Diagnosis by each observer was better than diagnosis with signal intensity ratios. CONCLUSION: MR imaging results can reflect thyroid function and histopathologic findings in the thyroid gland and help discriminate malignant lymphoma from Hashimoto thyroiditis.

Adult↗
PubMed1995

[The effects of mood and content on sentence memory in children].

This study examined the influence of positive and negative moods on memory in children. Short video clips, happy or sad, were shown to 394 third-grade children to manipulate their mood. Then sentences with positive or negative items were given for a learning task. The sentences had people's name, food or animal as their subject. Cued recall was then assessed with sentence subjects as cues. A mood-congruent effect was observed (a) when children learned sentences about foods or animals in a happy mood, and recalled them with food or animal cues; and (b) when they learned sentences about people's names in a sad mood, and recalled them with food or animal cues. A mood-incongruent effect was found (c) when they learned sentences about people's names in a sad mood, and recalled them with people's name cues. Interestingly, children recalled negative items more frequently than positive ones when they learned sentences with people's names. However, children appeared to be able to suppress such a negativity bias if they could control their mood.

Affect↗