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Biomedical subjects

N Takeuchi

Publications and source records attributed to N Takeuchi.

412 records · Page 23Linked to original sources
PubMedDate not supplied

CT and MR appearances of parotid pseudotumors in Sjögren syndrome.

The radiologic findings in eight patients with parotid pseudotumors associated with Sjögren syndrome (CT in eight; MRI in two) were retrospectively analyzed and compared with the findings in three cases with malignant lymphomas. Diagnosis of pseudotumor was obtained by surgery in six cases and by fine-needle aspiration biopsy and radiologic follow-up in the remaining cases. Six cases (75%) had advanced disease and the remaining had early disease. Both solid (75%) and cystic (38%) masses were seen in the patients with pseudotumors. The masses were solitary in 25%, multiple in 75%, unilateral in 25%, and bilateral in 75%. All three lymphomas were solid masses. The lymphomatous masses were not reliably distinguished from the solid pseudotumors.

Adult↗
PubMedDate not supplied

CT findings in "pseudoalveolar" sarcoidosis.

To determine the specific high resolution CT (HRCT) features for "pseudoalveolar" sarcoidosis, we reviewed HRCT of 10 patients with pathologically proven sarcoidosis. On HRCT the lesions of pseudoalveolar sarcoidosis were shown as homogeneous or inhomogeneous opacities 1-4 cm in diameter located either along the bronchovascular bundles or in the lung periphery adjacent to the pleural surface. The margin was irregular, and numerous nodules 1-2 mm in diameter were observed in the surrounding lung. Air bronchograms were observed in 6 patients. In addition to these lesions, other CT abnormalities such as nodules, groundglass opacities, thickened bronchovascular bundles, and interlobular septa were found in all 10 cases. Good response of pseudoalveolar sarcoid lesions to administration of corticosteroid was observed in all three cases in which follow-up CT was available.

Adult↗
PubMedDate not supplied

Comparison of high resolution CT findings of sarcoidosis, lymphoma, and lymphangitic carcinoma: is there any difference of involved interstitium?

PURPOSE: The purpose of this study was to determine distinguishing features of three diseases that are distributed along the lymphatics. METHOD: CT scans of 40 patients with lymphangitic carcinomatosis, 41 with sarcoidosis, and 44 with malignant lymphoma were retrospectively reviewed. We evaluated the degree of involvement of the interlobular septa, bronchovascular structures, subpleural interstitium, and other CT findings. RESULTS: The number of thickened interlobular septa and the extent of involvement of the subpleural interstitium in lymphangitic carcinomatosis were higher than those in sarcoidosis and malignant lymphoma (p<0.0001). Nodules of >1 cm in diameter were more often seen in malignant lymphoma (41.0%) than in the other two diseases (p < 0.001). Bilateral distribution was more common in sarcoidosis (100%) than in the others (p<0.001). CONCLUSION: The major difference among lymphangitic carcinomatosis, sarcoidosis, and malignant lymphoma is the greater involvement of the interlobular septa and subpleural interstitium in lymphangitic carcinomatosis than in either sarcoidosis or malignant lymphoma.

Adult↗
PubMedDate not supplied

Effects of a cholesterol-rich-diet and a hypolipidemic drug (clofibrate, CPIB) on Leydig cells in rats stereological and biochemical analysis.

Although the plasma testosterone level of the cholesterol-fed animals was almost the same as that of the control animals, the concentration in the tissue of the testis of the cholesterol group was 50% higher than that of the control group. Stereological data showed that the smooth endoplasmic reticulum of Leydig cells of the cholesterol group decreased by respectively 38 and 32% in volume as well as in surface area, and also mitochondria decreased by respectively 27 and 22% in volume as well as in surface area of inner membrane, as compared with the control group. Lipid droplets decreased remarkably in number and volume. Consequently Leydig cells of the cholesterol group diminished their cell volume to 83% of that of the control. When clofibrate was administered, the testosterone concentration in the testis tissue increased to 2.3 times that of the control group, although the plasma testosterone level was almost the same. In the Leydig cells of animals treated with cholesterol plus clofibrate peroxisomes decreased significantly and lipid droplets increased noticeably, as compared with the cholesterol-fed animals. These results might suggest that the testosterone production rate will decrease if the animals are fed for a longer period on a cholesterol-rich diet or immediately after the chow turns to a low-cholesterol-diet, and that the peroxisomes in the Leydig cells differ in their functional roles from those in the liver.

Animals↗
PubMedDate not supplied

Striatonigral degeneration combined with olivopontocerebellar atrophy with subcortical dementia and hallucinatory state.

We present an autopsied case of striatonigral degeneration (SND) combined with olivopontocerebellar atrophy (OPCA) with subcortical dementia and hallucinatory state. A Japanese woman without a remarkable family history showed hand tremor at the age of 35 years, followed by bradykinesia, muscle rigidity, orthostatic hypotension, neurogenic bladder and pyramidal signs. No obvious cerebellar symptoms were found. Various antiparkinsonian drugs were administered, but were not markedly effective for the parkinsonism. She developed a mild dementia characterized by mild memory disturbance with preservation of orientation, slowing of thought processes, emotional lability toward sadness, impaired ability to manipulate acquired knowledge and poor calculating, and by the absence of aphasia, apraxia and agnosia. The features in this patient were consistent with those seen in subcortical dementia. She also had auditory hallucinations. MRI revealed hypointense T2 signals in the putamina and substantia nigra. T1-weighted MRI demonstrated atrophy of both the pons and cerebellum in addition to atrophy of the putamina and substantia nigra. EEG showed slowing of background activity. She died of cardiac failure at the age of 47. Autopsy disclosed brain stem tegmental atrophy, SND, OPCA and many glial cytoplasmic inclusions in the central nervous system, but well-preserved cerebrum. We discuss the relationship between the psychiatric symptoms and pathologic findings of brain stem tegmentum.

Autopsy↗
PubMedDate not supplied

Treatment of branch retinal arterial occlusion with sodium ozagrel, a thromboxane A2 synthetase inhibitor.

A 47-year-old woman with branch retinal arterial occlusion treated with sodium ozagrel is described. The patient presented with acute visual field loss in her right eye. Blood tests demonstrated the elevation of beta-thromboglobulin and platelet factor 4. Sodium ozagrel, a thromboxane A2 synthetase inhibitor, 160 mg daily was administered for 14 days. This treatment prevented exacerbation of retinal arterial thrombosis and produced a marked improvement in the visual field loss. Sodium ozagrel may be a useful drug in the treatment of acute retinal arterial occlusion thought to be caused by thrombosis.

Enzyme Inhibitors↗
PubMedDate not supplied

Methylation analysis of cell cycle control genes in adult T-cell leukemia/lymphoma.

Central to many cancers is the aberrant expression of genes that regulate the cell cycle including the cyclin-dependent kinase inhibitors known as p15INK4b and p16INK4a, p14ARF and the retinoblastoma (RB) protein. We performed a detailed analysis of the methylation status of these genes by methylation specific polymerase chain reaction (MSP) in tumor cells of 35 adult T-cell leukemia/lymphoma (ATL) patients. We found in nine of 35 cases (26%) at least one gene methylated. The frequency of p15INK4b methylation was 7 of 35 (20%). The incidence of methylation of p14ARF and p16INK4a was two of 35 (6%) and one of 35 (3%), respectively. The RB gene was not found to be methylated in any of the ATL samples. The data indicate that inactivation of these cell cycle regulatory genes by hypermethylation is important in the development of ATL.

Cell Cycle Proteins↗
PubMedDate not supplied

MRI of anterior mediastinal tumors.

To compare the abilities of MRI (magnetic resonance imaging) and CT to provide information about anterior mediastinal tumors, we retrospectively evaluated the MR (n = 28) and CT images (n = 25) of patients with anterior mediastinal tumors. T1-weighted and T2-weighted images were obtained with spin echo sequences using cardiac gating. Six of 12 thymomas and seven of nine teratomas showed characteristic findings by MRI, while four of the 10 thymomas and five of the eight teratomas were correctly diagnosed by CT. The other tumors did not show a characteristic MR appearance. All nine malignant tumors were correctly diagnosed as malignant lesions on MR images, while one false positive case and one false negative case were recorded on CT images. We conclude that MRI and CT provide nearly the same information for the evaluation of anterior mediastinal tumors. However, in some cases, only MRI can provide information about malignancy or a specific diagnosis.

Adolescent↗
PubMedDate not supplied

Computed tomography and ultrasonography in parotid tumors.

To determine the most appropriate radiographic approach to parotid tumors, computed tomography (CT) was performed in 65 patients with 33 benign tumors, 19 malignant tumors, 3 abscesses and 10 other lesions with a clinical appearance of tumor. In 22 of the 65 cases CT-sialography and in 26 ultrasonography (US) were also performed. The mass was well recognized on CT without sialography in all patients, and the lesion was also well evaluated in all those examined with US. At CT-sialography the tumor was well shown, but this method made it difficult to differentiate a benign from a malignant lesion, because the character of the delineation and the border of the tumor were difficult to evaluate. It is concluded that US and CT without sialography are satisfactory for evaluating the parotid tumor, and the indication for CT-sialography is limited to those cases in which the tumor is demonstrated on US, but is unclear on conventional CT.

Adenoma, Pleomorphic↗
PubMedDate not supplied

Spontaneous pneumothorax caused by metastatic hemangioendothelioma. Radiographic appearance and pathologic correlation.

A patient with hemangioendothelioma is described, who developed a metastatic pulmonary nodule, subsequently a bullous lesion contiguous to the nodule, and finally spontaneous pneumothorax. In such cases, newly formed bullous lesions may conceal originally visible metastatic foci and can be a potential source of spontaneous pneumothorax.

Hemangioendothelioma↗
PubMedDate not supplied

Primary ovarian lymphoma associated with Meigs' syndrome: a case report.

A case is presented of primary undifferentiated lymphocytic lymphoma, non-Burkitt, of the right ovary associated with Meigs' syndrome. The diagnosis was based upon the findings of tumor imprint cytology, histopathology and electron microscopy. The ultrastructural observations were the most diagnostic, revealing well-developed, rough endoplasmic reticulum and dilated cisternae in the cytoplasm of the tumor cells. An association of Meigs' syndrome with a rare ovarian lymphoma has not been previously reported. The abnormal-appearing mesothelial cells in the pleural effusion were proven to be reactive and not malignant by comparison with the tumor cells demonstrated by imprint cytology of this ovarian lymphoma.

Adult↗
PubMedDate not supplied

Chronic eosinophilic pneumonia: evolution of chest radiograms and CT features.

OBJECTIVE: Our object is to describe and compare the findings on plain chest radiographs and CT scans in patients with chronic eosinophilic pneumonia of varying duration, as judged by their clinical history. MATERIALS AND METHODS: We retrospectively reviewed the initial chest radiographs and initial CT scans that were obtained before treatment with corticosteroid in 17 patients with pathologically proven or clinically diagnosed chronic eosinophilic pneumonia. RESULTS: Eleven of the 17 patients showed predominantly peripheral patchy or confluent consolidation with or without ground-glass opacities on chest radiography. Sixteen patients, on the other hand, showed various types of abnormalities with peripheral predominance on CT. The seven patients in whom the initial CT was performed within 1 month after the onset of symptoms had dense confluent consolidation (7/7) with or without ground-glass opacities. When the initial CT was performed 1-2 months after onset of symptoms, inhomogeneous patchy consolidation or nodules (5/7) or ground-glass opacities (2/7) were observed. When the initial CT was performed > 2 months after the onset of symptoms, streaky or band-like opacities (1/3) or lobar atelectasis (1/3) was seen. CONCLUSION: Patients with chronic eosinophilic pneumonia show an evolution of CT features at varying time intervals after the onset of disease.

Adult↗
PubMedDate not supplied

Metastatic pulmonary calcification: early detection by high-resolution CT.

A 41-year-old man with a renal transplant was admitted with cough, fever, and dyspnea. Although chest radiography was normal, high-resolution CT demonstrated small hazy round opacities in the centrilobular regions throughout both lungs. The biopsy specimen revealed metastatic calcification in the alveolar septa and the walls of the bronchioles and arterioles. High-resolution CT may be useful for the early detection of metastatic pulmonary calcification when plain radiography is negative and therapy has the potential to reverse the process.

Adult↗
PubMedDate not supplied

Establishment of a daunorubicin-resistant cell line which shows multi-drug resistance by multifactorial mechanisms.

We established a daunorubicin (DNR)-resistant cell line derived from human leukemia cell line K562, (K562/D1-9), which also shows multidrug resistance (MDR). K562 cells were cultured with serially increasing concentrations up to 1.0 microM of DNR and then cloned by the limiting dilution method. K562/D1-9 cells were found to be 28 times more resistant to DNR than their its parent cells. Intracellular accumulation of DNR in K562/D1-9 was less than in the wild type, and P-glycoprotein (PGP) was overexpressed. Both DNR resistance and its intracellular accumulation were partially reversed by addition of verapamil to K562/D1-9 cells, but not to K562 cells. Topoisomerase II (Topo II) activity was decreased in K562/D1-9 cells. In contrast to other drugs, such as doxorubicin and vincristine, verapamil could not reverse drug resistance to VP-16 in the K562/D1-9 cell line, suggesting the importance of Topo II as the target of MDR. Protein kinase C (PKC) level was higher in K562/D1-9 than in K562. These findings suggested that the mechanism of MDR in this cell line might be multifactorial, including PGP, topo II and PKC. The K562/D1-9 cell line may be a good model for studying drug resistance in leukemia chemotherapy.

Antibiotics, Antineoplastic↗
PubMedDate not supplied

Usefulness of high-resolution CT for differential diagnosis of multi-focal pulmonary consolidation.

To determine whether high-resolution CT (HRCT) is useful for diagnosing patients with multi-focal pulmonary consolidation observed on chest radiography, we reviewed the HRCT scans of 80 patients with various kinds of diseases. The patients were divided into three groups: those with infectious diseases (group A, n = 28), those with non-infectious diseases in which the use of corticosteroids was the treatment of choice (group B, n = 33), and others (group C, n = 19). Centrilobular branching structure, small nodules within the consolidation, and segmental distribution were specific or more prevalent in group A. Ground-glass attenuation, air-bronchiologram, and non-segmental distribution were more prevalent in group B. Consolidation composed of central homogeneous area and its surrounding small nodules was specific for group C, especially for sarcoidosis. In conclusion, HRCT provides more useful information in diagnosing patients with multifocal consolidation than does chest radiography or conventional CT.

Adolescent↗