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N Yamada

Publications and source records attributed to N Yamada.

At least 451 records · Page 25Linked to original sources
PubMed1995

[Contribution of carbohydrate antigens to endothelial E-selectin binding in cancer cells].

We first investigated the difference in carbohydrate antigens' expression between primary tumors and matched metastatic liver lesions of colorectal carcinomas, using immunohistochemical methods. Regarding the degree of expression, SLA, SLX and SPan-1 antigens were found to be expressed on a larger proportion of tumor cells in liver metastases than in primary tumors. Second, comparing the expression of carbohydrate antigens on highly metastatic colon cancer cell line to the parental line, the expression of SLA on the surface of highly metastatic variant was increased more intensively than the parental line. Finally, we investigated the contribution of carbohydrate antigens to endothelial E-selectin binding in colon and pancreatic cancer cells, and the results indicated that SLA might play a significant role in this binding. These findings suggest that the expression of carbohydrate antigens on the surface of cancer cells obviously contributed to E-selectin binding and also to metastatic potential.

Antigens, Tumor-Associated, Carbohydrate↗
PubMed1995

[An analysis on fat digestion in the upper small intestine after intragastric infusion of a test meal in patients with exocrine pancreatic insufficiency].

To clarify the mechanism of the fat maldigestion in 9 patients with exocrine pancreatic insufficiency, lipase activities, pH, and micellar lipids in the upper small intestinal contents were studied. The upper small intestinal pH was slightly less in patients with exocrine pancreatic insufficiency than in healthy controls. Lipase activities and micellar lipids were significantly reduced in patients with exocrine pancreatic insufficiency compared with in healthy controls. There was a significant correlation between serum cholesterol and micellar cholesterol concentrations. The results suggest that there is maldigestive state in the digestion-absorption process in patients with exocrine pancreatic insufficiency due to insufficiency of lipase secretion and that insufficiency of lipase secretion disturbs hydrolysis of triglyceride and prevents micelle formation and leads to reduced uptake of cholesterol into micellar phase and it is reflected in serum cholesterol.

Adult↗
PubMed1995

[A case of papillary muscle rupture associated with acute inferior myocardial infarction].

A sixty-year-old man was admitted to our hospital due to prolonged left anterior chest oppression and hypotention. The electrocardiogram revealed acute inferior myocardial infarction, confirmed by the coronary angiography which showed occluded right coronary artery (RCA) at the segment 4AV. The intra-coronary pro-urokinase infusion and coronary angioplasty successfully revascularized the occluded 4AV segment. Although the 4AV segment perfused small area, he developed severe pulmonary edema on the second hospital day. A transesophageal echocardiography revealed severe mitral regurgitation due to posterior mitral valve prolapse by the ruptured tendineae with a mobile mass. The damaged mitral valve was replaced by the prosthetic mechanical valve (SJM 25M), resulted in stable hemodynamic state. He discharged one month after the operation.

Acute Disease↗
PubMed1995

[Role of carbohydrate antigens in cell-cell and cell to extracellular matrix adhesion on pancreatic cancer].

We investigated the variable adhesiveness of pancreatic cancer cells by glycosylation inhibitor to elucidate the role of carbohydrate antigens in cell-cell and cell to extracellular matrix adhesion. Various carbohydrate antigens were strongly expressed on pancreatic cancer cell (SW1990) by ELISA, and these expression correlated to its in vitro invasiveness and in vivo metastatic potential. Cellular adhesion to Matrigel, laminin and collagen type IV and homotypic cellular aggregation in SW1990 were enhanced by reducing O-linked glycosylation with its inhibitor (Bzl-GalNAc), and these effect were reversed by additional purified mucins. These results suggested that O-linked glycoproteins on SW1990 cell surface may inhibit its adhesiveness to the substratum and aggregation properties by hindering surface receptors, and this variability of adhesiveness induced by altered glycosylation may have an another important role in highly metastatic potential of well glycosylated cancer cells.

Adenocarcinoma↗
PubMed1995

[The changes in nuclear DNA content in acquisition of a high capacity for metastasis of human cell lines].

Quantification of nuclear DNA content in cancer is considered a prognostic factor, and several investigators have demonstrated that aneuploid tumors are more aggressive than diploid tumors. In this report, we investigated the relationship between metastatic capacity and nuclear DNA content using gastric and colon cancer cell lines. We established a highly peritoneal metastatic cell line (2M-D3) from a gastric cancer cell line (2M) and a highly liver metastatic cell line (LM-H3) from colon cancer cell line (LM) in our laboratory. Both the highly metastatic cell lines have more capacity for growth and metastasis, but lower nuclear DNA content and chromosome numbers than these parental cell lines. The results indicated that metastatic capacity was inversely proportional to nuclear DNA content. We cannot provide a satisfactory explanation for this inverse correlation between metastatic capacity and nuclear DNA content, but it is supposed that each cancer cell may have suitable and stable nuclear DNA content in metastasis.

Animals↗
PubMed1995

Mucopolysaccharidosis IVA: identification of a common missense mutation I113F in the N-Acetylgalactosamine-6-sulfate sulfatase gene.

Mucopolysaccharidosis IVA is an autosomal recessive lysosomal storage disorder caused by a deficiency of N-acetylgalactosamine-6-sulfate sulfatase. The recent isolation and characterization of cDNA and genomic sequences encoding GALNS has facilitated identification of the molecular lesions that cause MPS IVA. We identified a common missense mutation among Caucasian MPS IVA patients. The mutation was originally detected by SSCP, and successive sequencing revealed an A-->T transversion at nt 393. This substitution altered the isoleucine at position 113 to phenylalanine (I113F) in the 622 amino acid GALNS protein and was associated with a severe phenotype in a homozygote. Compound heterozygotes with one I113F-allele mutation have a wide range of clinical phenotypes. Transfection experiments in GALNS-deficient fibroblasts revealed that the mutation drastically reduces the enzyme activity of GALNS. Allele-specific oligonucleotide or SSCP analysis indicated that this mutation accounted for 22.5% (9/40) of unrelated MPS IVA chromosomes from 23 Caucasian patients, including 6 consanguineous cases. Of interest, the I1e 113-->Phe substitution occurred in only Caucasian MPS IVA patients and in none of the GALNS alleles of 20 Japanese patients. These findings identify a frequent missense mutation among MPS IVA patients of Caucasian ancestry, that results in severe MPS IVA when homoallelic, and will facilitate molecular diagnosis of most such patients and identification of heterozygous carriers. In addition to this common mutation, 10 different point mutations and 2 small deletions were detected, suggesting allelic heterogeneity in GALNS gene.

Base Sequence↗
PubMed1995

[A case of predominantly right-temporal lobe atrophy with disturbance of identifying familiar faces].

A right-handed 72-year-old man (I.K.) who complained of difficulty identifying familiar faces was investigated on a series of tests of face perception (face matching, recognition of age and sex, and meaning of facial expressions), facial identity (faces of families and famous persons as retrograde ones and his doctor's faces as anterograde ones) and other neuropsychological abilities. His scores of face perception tests were normal or mildly disturbed. His memory performances measured with WMS-R and Rey-Osterrieth figure were normal. But he could identify none of anterograde and retrograde faces and failed to experience any familiarity with those faces. In addition, he could not recognize none of voices of family members and a doctor, despite of being able to recognize about the age and sex of voice. On the other hand, he could describe personalities of his family members and doctors, but knew none of famous people. Memory for personal events in the recent and remote past was well preserved, while that for social events was severely disturbed in both past. In addition to impairment of identification of familiar faces, he had severe problems with identifying famous common buildings and animals. He also presented Gogi (word meaning) aphasia and impairment of semantic memory for some common objects. Tyrrell et al. reported a similar case and McNeil et al. examined the patient on covert recognition of face in detail. On their task, he showed no covert effects and they attributed the result to impairment of face recognition units themselves. Their way of thinking seems to give an explanation of I.K.'s disturbance of anterograde and retrograde memory for faces.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1995

[Establishment of a new scirrhous gastric cancer cell line OCUM-2M from a primary gastric tumor].

We report on the establishment and characterization of a scirrhous gastric cancer cell line, designated OCUM-2M, derived from a 49-year-old Japanese female. OCUM-2M was derived from a primary tumor of stomach taken by total gastrectomy. The cell line grew singly or in clusters in the cultured medium. The cell line continued to multiply for more than one year. Doubling time was 37.3 hours, chromosomal mode was 70. The DNA ploidy pattern was aneuploid and DNA index was 1.59. It produced several tumor-associated antigens such as CEA, CA19-9, SLX and SPan-1. The cell line was transplantable in athymic BALB/c nude mice, and histological findings of the xenografted tumor showed poorly differentiated adenocarcinoma. The growth of OCUM-2M was stimulated following the addition of EGF, b-FGF and KGF, and decreased following the addition of TGF-beta 1. This cell line is useful in vitro and in vivo systems for studies of the biology of scirrhous gastric carcinoma.

Adenocarcinoma, Scirrhous↗
PubMed1995

[Pharmacokinetics of subconjunctivally injected drugs in the anterior segment of rabbit eyes].

We injected 12.5, 25, 50 and 100 microliters portions of a combined solution of 2.5% sodium fluorescein (FL), 2.5% cefmenoxim hemihydrochloride (CMX), and 0. 25% chloramphenicol (CP) subconjunctivally into rabbit eyes by various methods. Drug levels were monitored in the tears and aqueous humor and measured via high performance liquid chromatography. In the tear fluid, the concentrations of CP decreased more rapidly with time than FL and CMX. The drugs penetrated the rabbit's eyes better when injected subconjunctivally than when administered by sub-Tenon's injection. After subconjunctival injection through the eyelid, the drug concentration in the tears decreased with time in almost the same way as for injection through the conjunctival membrane. There was little difference between the presence and absence of a puncture hole in the conjunctiva. When the whole cornea was sealed with cyanoacrylate glue to block transcorneal absorption, the FL concentration in the aqueous humor was 30% of that in the control and the CP concentration was less than 10% of that in the control. About 70% of FL penetrating the eyes was derived from the transcorneal route but most of the CP was derived from the transcorneal route. FL in 1% or 0. 25% sodium hyarulonate (HA) and saline was injected subconjunctivally, and the concentrations of FL in the cornea and vitreous humor were measured. FL in 0.25% HA penetrated rabbit eyes better than that in 1% HA. These findings suggest that by dissolving the drug in an adequate concentration of HA solution, better penetration of drugs into the eye can be obtained.

Animals↗
PubMed1995

[Care for patients with Pick's disease--by using their preserved procedural memory].

Pick's disease are more often complicated than Alzheimer's disease by behavioral disturbances such as social misconduct and stereotypy, that are troublesome and clinically difficult to manage. The purpose of this study was to investigate the possibility of improvement in care for patients with Pick's disease by using their presumably preserved procedural memory. Four inpatients and two outpatients with Pick's disease were studied. Case 1: A 54-year-old right-handed retired clerk presented with a 3-year history of increasing restlessness, word-finding difficulty and impaired comprehension of nominal terms. He was forced to retire from his work because of his social misconduct and incommunicability. On admission he wandered about the ward irritably, did not enter into any conversation, and destroyed all keys in the ward by putting a pencil into keyholes. Neuroradiological examination revealed circumscribed bilateral frontotemporal atrophy which was more marked on the left side. However, he has become more adaptive to the life in the ward and his expression has become peaceful since he began to play othello games with other patients and his doctors. Case 2: A 71-year-old right-handed housewife had progressively altered in her personality and behavior over 4 years. She was restless and showed striking palilalia with marked right frontotemporal atrophy when initially evaluated 2 years after her initial symptoms. Subsequently, her verbal output decreased. She ate large amounts of food and her overweight became a serious problem in her care at home. On admission she wandered about the ward irritably, ate meals of other patients, and put on a quilt on their head. However, these troublesome behavior disappeared when she was bent on knitting that was her former hobby. Case 3: A 63-year-old right handed physician presented with a 5-year history of increasing word-finding difficulty and impaired comprehension of nominal terms. His conversation was limited to continuous repetition of a few phrases. He wandered into several hospitals around his house in fixed order every day. On examination, he was mildly disinhibited and distractible with circumscribed bilateral frontotemporal atrophy which was more marked on the left side. Wandering away from home overnight necessitated admission to the hospital. In the ward he wandered about and tried to open each door restlessly and irritably. However, he has become calm and his expression has become peaceful since he was conducted to measure blood pressures of his nurses. Case 4: A 65-year-old right-handed retired office worker.(ABSTRACT TRUNCATED AT 400 WORDS)

Aged↗
PubMed1995

Serum aldolase level is a useful indicator of disease activity in eosinophilic fasciitis.

The serum levels of muscle enzymes have been considered normal in patients with eosinophilic fasciitis (EF). We observed elevated serum aldolase levels in 3 patients with EF. Serum creatinine kinase levels were within the normal range. We measured the aldolase levels longitudinally. In all patients, the levels decreased to the normal range after oral corticosteroid treatment, and skin sclerosis improved. Afterwards, serum aldolase levels increased again, with the recurrence of skin sclerosis. These observations suggest that serum aldolase level may be a useful indicator of disease activity.

Adult↗
PubMed1995

Ultrahigh-resolution low-voltage SEM reveals ultrastructure of the glucan network formation from fission yeast protoplast.

The refined field emission SEM, S-900 LV which gives better resolution especially at low voltages below 5 kV was developed for ultrahigh resolution scanning electron microscopy. A visualization test at x 300,000 was made using a gold-evaporated magnetic tape, and the resolution was found to be about 1 nm at 2.5 kV. The ultrastructure of the cell wall, especially the reverting glucan network, from the protoplast of Schizosaccharomyces pombe was studied using this improved ultrahigh-resolution low-voltage SEM (UHR-LVSEM). The results with uncoated reverting protoplasts observed with this microscope revealed that the network was originally formed as secreted particles scattered on the protoplast surface and these were subsequently stretched to microfibrils about 2 nm thick. The microfibrils were twisted around each other and joined together so that they developed into 8-nm-thick fibrils, forming a ribbon-shaped network of glucans about 16-nm-thick which covered the entire protoplast surface. The UHR-LVSEM images of reverting protoplasts treated with glucanase confirmed that the particles scattered on the protoplast surface in the initial stage of regeneration were glucan in nature.

Animals↗
PubMed1995

[Chronological analysis of eosinophil infiltration in mite-allergen induced dermatitis in atopic patients].

To elucidate the active process of eosinophil infiltration in atopic dermatitis (AD), we performed patch testing using crude mite allergens on normal-appearing skin in adult AD patients with high levels of mite-specific IgE antibodies and analyzed positive reaction sites chronologically by histological and immunohistological methods. Positive reactions were observed in 6 out of 9 AD patients (66.7%), whereas none of 7 non-AD control subjects showed positive reactions. Skin biopsies were obtained from positive reaction sites at 2,6,12,24 and 48 hours after allergen challenge. Eosinophils were seen within postcapillary venules at 2 hours, followed by increased perivascular eosinophil infiltration at 6 hours which peaked at 24 and 48 hours. Epidermal eosinophilic spongiosis was also observed at 48 hours. The majority of infiltrating eosinophils showed positive reactions for BMK-13 and 15-59% of them were EG2 positive activated eosinophils. BMK-13, EG2 and anti-EP positive reactions were scattered throughout connective tissue and their areas were time-dependently increased. These findings suggest that eosinophil transmigration and activation play an important role in initiating early AD lesions induced by transepidermal mite allergen permeation.

Adult↗
PubMed1995

Increased expression of sialyl Lewis A and sialyl Lewis X in liver metastases of human colorectal carcinoma.

Sialyl Lewis A (SLA) and sialyl Lewis X (SLX) have been shown to be specific ligands for endothelial leukocyte adhesion molecule-1 (ELAM-1), and may be involved in the process of adhesion between cancer cells and endothelium. We used immunohistochemical methods to study the expression of SLA, SLX and CEA in both primary tumors and matched metastatic liver lesions of colorectal carcinomas. Specimens from primary tumors and matched liver metastases from 24 patients with colorectal carcinomas were studied immunohistochemically. The degree of expression of CEA in liver metastases was similar to that in primary tumors, but SLA and SLX were expressed on a larger proportion of tumor cells in liver metastases than in primary tumors. Our findings suggest that colorectal carcinoma cells expressing SLA and/or SLX form metastatic liver tumors. They also suggest that expression of SLA and SLX in primary of colorectal carcinoma can be used as a prognostic indicator of metastasis.

Adult↗
PubMed1995

Synthesis of alpha-anomeric homopyrimidine oligo DNA phosphorothioates and their physicochemical and biochemical properties.

alpha-Anomeric 2'-deoxycytidine and thymidine were synthesized in a stereospecific manner. With these nucleosides, pyrimidine homooligomers having either exclusively phosphodiester or phosphorothioate linkages were prepared using phosphoramidite method. All tested alpha-DNA.RNA complex was found to be inert toward the action of RNase H, even when phosphorothioate analogs were used as the DNA component. Among the alpha-anomeric homooligomers, alpha-oligocytidilate phosphorothioate exhibited potent inhibitory effect towards the action of RNase H on a DNA.RNA complex.

Antiviral Agents↗