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Biomedical subjects

T Hara

Publications and source records attributed to T Hara.

At least 757 records · Page 42Linked to original sources
PubMed1992

[Detection of mediastinal lymph node metastasis from lung cancer with positron emission tomography (PET) using 11C-methionine].

Twenty-five patients with primary non-small cell lung cancer underwent the positron emission tomography (PET) using 11C-methionine to detect the mediastinal lymph node metastasis. We introduced the positron angiography to recognize precisely the anatomical orientation of the mediastinal lymph nodes. The 11C-uptake of the lymph node was expressed with distribution absorption ratio (DAR). A total 107 lymph nodes were examined. The average DAR in metastatic lymph nodes (n = 28) was 3.89 while that of non-metastatic nodes (n = 79) was 2.38 indicating a significant difference (p < 0.001). The most adequate threshold for detection of metastasis was 3.3 with sensitivity of 100%, and specificity of 87.3% and overall accuracy of 89.7%. Metastasis of squamous cell carcinoma was diagnosed more accurately than that of adenocarcinoma. Thus, PET using 11C-methionine may offer a new method to detect the mediastinal lymph node metastasis from lung cancer.

Adult↗
PubMed1992

Effects of aging on renal response to parathyroid hormone in vitro.

Renal cortex homogenates from aged (greater than 5 y) rabbits showed decreased specific activities of brush border membrane enzymes compared to those from control young (6 m) rabbits but the specific enzyme activities of basolateral membrane, endoplasmic reticulum and mitochondria did not differ between the two groups. The stimulatory effects of parathyroid hormone (PTH) on the Ca(2+)-pump enzyme [(Ca(2+)+Mg2+)-ATPase] activity in kidney cortex homogenates were markedly less in aged rabbits, but the effect of cAMP on this enzyme activity was similar. Moreover, the production of cAMP induced by PTH was markedly less in the renal cortex homogenates from aged rabbits. From these results, we have proposed the following mechanism; aging--decrease in the response of cAMP to PTH in renal cortex--decrease in the stimulatory effect of PTH via cAMP on the Ca(2+)-pump enzyme--decreased reabsorption of Ca2+ from ureter--increased urinary Ca2+ secretion. This pathway may contribute to the worsening of senile osteoporosis.

Aging↗
PubMed1992

Metabolic aspects of endothelial cells cultured from rat aortae.

We measured the lactate production, oxygen uptake and ATP in aortic endothelial cells cultured from young Wistar female rats. For these experiments, thoracic aortae were removed from the animals, minced into small pieces and transferred onto culture plates, to which a growth factor was added. When the endothelial cells had proliferated, the original pieces were removed from the culture and the remaining cells were subcultured until the 3rd passage. Regarding the growth curves of the 3rd passage, a logarithmic growth phase (Pg) was found from the 2nd to the 7th days and a stationary phase (Ps) followed thereafter. The ATP levels in the Pg and Ps were unchanged. Rates of lactate production and oxygen uptake were higher in the Pg than in the Ps. Only in the Ps was an interrelationship between these estimations found, suggesting that the confluent state exhibits metabolic cooperation between the cells in culture.

Adenosine Triphosphate↗
PubMed1992

Accommodative intraocular lens with spring action--Part 2. Fixation in the living rabbit.

After cataracts in 10 eyes of 8 pigmented or albino rabbits had been removed by phacoemulsification, a specially designed 10.0 x 8.5-millimeter accommodative intraocular lens with spring action ("spring IOL") was implanted through a 4.5- to 5.0-millimeter "dumbbell" linear anterior capsular opening. The average follow up was 11 +/- 8 months. All the spring IOLs were almost completely fixed in the capsular bag, and the anterior and posterior capsules remained transparent. However, due to limitations specific to the rabbit, no accommodative power could be detected; also, we observed lens epithelial cells and subsequent fibrous production proceeding from the equatorial area into the area between the optics.

Accommodation, Ocular↗
PubMed1992

Intraocular lens implantation in an almost completely retained capsular bag with a 4.5- to 5.0-millimeter linear dumbbell opening in the human eye.

As a preliminary step in developing a capsular opening that will permit the firm fixation of the full-size intraocular lenses (IOLs) of the future in a completely retained capsular bag, conventional 11-millimeter long posterior chamber IOLs with 6-millimeter polymethylmethacrylate optics were implanted in almost completely retained capsular bags with a 4.5- to 5.0-millimeter linear dumbbell opening. Undergoing the procedure were 23 cataractous eyes of 23 patients (average age, 72 +/- 8 years). Average follow up was 15 +/- 2 months. The dumbbell opening was made with an automated electric trephine or manually. The Cavitron 10,000 was used for phacoemulsification. Lens epithelial cell removal was performed by cryopexy. All IOLs were fixed in the capsule satisfactorily. Although complete transparency was not retained in any of the eyes, postoperative visual acuity was better than 10/20 in 16 eyes (70%). There were no apparent complications other than anterior capsular opacification.

Aged↗
PubMed1992

Anterior capsular opacification after endocapsular cataract surgery.

The central parts of the opacified anterior capsules of nine eyes of nine patients after endocapsular phacoemulsification followed by posterior chamber intraocular lens implantation were removed after an average postoperative period of 25 months and examined by light and electron microscopy. The opacified materials were judged to be collagen. Transmission electron microscopy revealed fibers 50 to 60 nm in diameter, with approximately 65-nanometer periodic bands in five of the nine eyes. Most remaining cells showed multilayered proliferation and were rich in cytoplasmic microtubules and surface dendrites. These results indicate that postoperative anterior capsular opacification is composed of fibroblast-like cells, presumably transformed from lens epithelial cells and collagen.

Aged↗
PubMed1992

[Adrenal myelolipoma associated with Cushing's syndrome: a case report].

A 42-year-old woman was referred to our hospital for evaluation of severe hypertension. A right adrenal tumor was revealed by CT scan, and the elevation of cortisol and u-17OHCS was found. We made a diagnosis of adrenal adenoma with Cushing's syndrome and performed right adrenalectomy. However, a small myelolipoma (1.5 mm in diameter) was found beside the cortical adenoma by histopathological examination. Adrenal myelolipoma is not a rare disease now, because it is easily-detected as an incidental by CT scan. The present case of adrenal myelolipoma, however, is interesting and uncommon in its connection with functioning cortical adenoma. Only 3 cases have been previously reported so far in English and Japanese publications. We discuss the etiology of adrenal myelolipoma, and suggest that myelolipoma would develop in the course of regressive or necrotic degeneration of cortical cells by hormonal disorders, stress, circulatory disturbance or other unknown factors.

Adenoma↗
PubMed1991

High density lipoprotein cholesterol as a mechanistic probe for the side chain cleavage reaction.

Cholesterol side chain cleavage reaction catalyzed by purified cytochrome P-450scc was stimulated 4-5 fold when cholesterol in rat high density lipoprotein was used as a substrate as compared to the case where cholesterol plus 0.1% Emulgen 911 was used. In the case of the cholesterol-Emulgen system, the Vmax value of activity was not obtained even when a 20 times molar excess of adrenodoxin over the cytochrome was used. However, in the case of the lipoprotein, a 2-3 times molar excess of adrenodoxin over the cytochrome was enough to obtain the half value of Vmax. HPLC gel filtration experiments showed that the three enzymes were eluted from the column as a complex regardless of adding the lipoprotein as judged by the activity and the blotting analysis. However, the activity with the lipoprotein was detected significantly earlier than that in the absence. These and other lines of evidence suggest that the lipoprotein vesicles promote a complex formation among the three enzyme components and serve as a probe for emphasizing a significance of a cluster mechanism in the reaction.

Adrenal Cortex↗
PubMed1991

Purification and characterization of ATPase from Nitrobacter winogradskyi.

An ATPase was purified from Nitrobacter winogradskyi, and some of its molecular and enzymatic properties were determined. The enzyme was composed of two subunits of 64 and 59 kDa, respectively. The enzyme had its pH optimum at 9.5 and showed a specific activity of 7 units per mg protein. This activity was about 14% and 18% of that of F1-ATPases obtained from Escherichia coli and Sulfolobus acidocaldarius, respectively. The enzyme was 29% and 6% inhibited by 100 microM dicyclohexylcarbodiimide (DCCD) and 100 microM NaN3, respectively. It was not inhibited by 20 mM NaNO3.

Adenosine Triphosphatases↗
PubMed1991

Granulocyte colony-stimulating factor in cerebrospinal fluid from patients with meningitis.

Granulocyte colony-stimulating factor (G-CSF) in the cerebrospinal fluid from patients with meningitis was measured by our modified enzyme-linked immunosorbent assay for G-CSF. The minimal detection level was 20 pg/mL G-CSF. In patients with bacterial meningitis, the G-CSF levels in the cerebrospinal fluid were extremely elevated, showing a mean value of approximately 1,500 pg/mL. On the other hand, G-CSF levels in the cerebrospinal fluid from 67% patients with aseptic meningitis were moderately increased, showing a mean value of about 80 pg/mL, whereas G-CSF levels in 33% samples remained undetectable. The G-CSF levels and neutrophil counts in the cerebrospinal fluid were proven to be related by Spearman's rank correlation coefficient analysis (r = .724). These elevations of G-CSF levels at inflammation sites associated with bacterial meningitis may indicate that G-CSF plays an important role in the combat of bacterial infections.

Child↗
PubMed1991

Had-1, a uridine 5'-diphosphogalactose transport-defective mutant of mouse mammary tumor cell FM3A: composition of glycolipids, cell growth inhibition by lactosylceramide, and loss of tumorigenicity.

Glycolipid compositions of mouse mammary tumor cell FM3A and its Newcastle disease virus-resistant mutant cell, Had-1, which was also characterized as a defective mutant of UDP-galactose transport to Golgi apparatus, have been studied. The major neutral glycolipid in FM3A was Gal beta 1-4Glc beta 1-1Cer (LacCer) (95%) and the rest was Glc beta 1-1Cer. The concentration of neutral glycolipids in Had-1 was only about one-fifth of that in FM3A. GlcB1-1Cer in Had-1 accounted for 79% of neutral glycolipids and the rest was LacCer, the content of which was decreased to 4% of that in FM3A. Ganglioside patterns of the two cell lines were similar, although gangliosides with N-glycolylneuraminic acid were increased in Had-1 cells compared with that in FM3A cells. The presence of NeuAc alpha 2-3-Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc beta 1-1Cer, NeuAc alpha 2-3Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4GlcNAc beta 1-3Gal beta 1-4Glc beta 1-2Cer, GM3, and GD3 was demonstrated by thin-layer chromatography immunostaining. 125I-Labeled Newcastle disease virus bound only poorly to gangliosides extracted from either FM3A or Had-1 cells on a high performance thin-layer chromatography plate. The effects of glycolipids on the growth of the two cell lines were also studied. Had-1 cells were more sensitive to glycolipids added exogenously than FM3A cells. Addition of GM3 had a stimulative effect on cell growth of Had-1. LacCer, Gal beta 1-3GalNAc beta 1-4Gal beta 1-4Glc beta 4-1Cer, and Glc beta 1-1Cer inhibited the growth of Had-1 cells. LacCer was the most potent inhibitor. LacCer immobilized on the culture plate also inhibited the growth of Had-1 cells. The inhibitory effect was recovered completely overcome by transferring the cells to LacCer-free medium. Had-1 cells were not tumorigenic in C3H/He mice, and furthermore the tumorigenic activity of FM3A cells was suppressed by the prior administration of Had-1 cells.

Animals↗
PubMed1991

Fourier transform infrared spectroscopic study on retinochrome and its primary photoproduct, lumiretinochrome.

Structural studies of retinochrome, and its photoproduct, lumiretinochrome, were done by Fourier transform infrared difference spectroscopy. The absorption bands in the carbonyl stretching region which shift in D2O show the changes in the protein part during the photoreaction. Strong absorption bands in the finger-print region show that the all-trans-retinal chromophore in retinochrome isomerizes to the 11-cis-retinal chromophore in lumiretinochrome upon illumination with yellow-green light at 83K.

Animals↗
PubMed1991

Specific uptake of asialofetuin-tacked liposomes encapsulating interferon-gamma by human hepatoma cells and its inhibitory effect on hepatitis B virus replication.

Asialofetuin-tacked liposomes (AF-liposomes) encapsulating interferon (IFN)-gamma were bound and internalized into a human hepatoma cell line, HepG2 cells, selectively through asialoglycoprotein receptor, but not non-tacked liposomes (N-liposomes). AF-liposomal IFN-gamma was more effective for inhibition of viral DNA replication in hepatitis B virus (HBV)-producing clone from HepG2 cells transfected with HBV-DNA than N-liposomal IFN-gamma. AF-liposomes may increase the therapeutic potential of IFN-gamma through asialoglycoprotein receptor in treating HBV-infected hepatocytes.

Asialoglycoprotein Receptor↗
PubMed1991

Free muscle transplantation combined with intercostal nerve crossing for reconstruction of elbow flexion and wrist extension in brachial plexus injuries.

Complete paralysis due to traumatic brachial plexus injury is extremely difficult to treat when the injury affects whole nerve roots and when motor function fails to show any signs of recovery. Seddon has suggested that arthrodesis of the shoulder and amputation at the humerus, combined with the use of a functional upper extremity prosthesis, was the most practical procedure available. Since 1965, in cases of irreparable lesions such as complete root avulsion type injuries, we have performed direct intercostal nerve crossing to the musculocutaneous nerve without free nerve graft to achieve elbow flexion. However, it is necessary to operate on the patient within 6 months following the injury to obtain good results. In the past there was no procedure for dealing with delayed cases of complete brachial plexus palsy. However, with the advent of microsurgical techniques, new approaches have become open to us. Since 1978, we have reconstructed the elbow flexor by the combined surgery of free muscle transplantation with intercostal nerve crossing in delayed cases of complete paralysis. This article introduces the operative technique and the results we have obtained.

Adolescent↗
PubMed1991

Detection of multidrug-resistant protein, P-glycoprotein in childhood leukaemia and lymphoma.

Flow cytometric detection of surface P-glycoprotein, a multidrug-resistant gene product, with a monoclonal antibody, MRK 16, was performed on cells obtained from 18 children with leukaemia and lymphoma. Of 18 patients examined, 1 with malignant lymphoma at relapse showed a significant increase in P-glycoprotein-positive cells and a strong resistance to chemotherapy. Overexpression of P-glycoprotein in a case with B-cell type malignant lymphoma was confirmed by immuno-precipitation and Northern hybridization analysis. The present study suggests that an increased expression of surface P-glycoprotein might be involved in multidrug resistance at least in a certain case of childhood leukaemia and lymphoma.

ATP Binding Cassette Transporter, Subfamily B, Mem↗