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Y Anzai

Publications and source records attributed to Y Anzai.

At least 37 records · Page 2Linked to original sources
PubMed1994

Application of the random amplified polymorphic DNA using the polymerase chain reaction for efficient elimination of duplicate strains in microbial screening. II. Actinomycetes.

We evaluated the random amplified polymorphic DNA (RAPD) method using Streptomyces lavendulae and Streptomyces virginiae strains to eliminate duplicate actinomycete strains in our microbial screening program. The RAPD data were compared with phenotypic characteristics, DNA relatedness, HPLC analysis of metabolites and low-frequency restriction fragment analysis by pulsed-field gel electrophoresis. These results were consistent with each other. Therefore, we conclude that RAPD is a simple, efficient, and reliable method for the selection of actinomycete strains.

Base Sequence↗
PubMed1994

Dextran-coated superparamagnetic iron oxide, an MR contrast agent for assessing lymph nodes in the head and neck.

PURPOSE: To investigate dextran-coated superparamagnetic iron oxide particles (BMS 180549) as an MR contrast agent for assessing lymph nodes. METHODS: Five different doses ranging from 0.3 to 1.7 mg Fe/kg were evaluated in five healthy human male subjects as part of a phase 1 clinical study. T1-, T2-, and proton density-weighted spin-echo images as well as multiplanar gradient-echo and spoiled gradient-echo images were acquired before and 1 hour, 4 hours, and 24 hours after contrast administration. Image analysis was performed with visually selected regions of interest. Signal intensities were measured for neck lymph nodes and the adjacent muscle. Enhancement effects were evaluated as a function of dose, imaging time after contrast administration, and MR pulse sequence. RESULTS: The iron oxide particles were phagocytized by macrophages within the normal functioning lymph nodes, resulting in a dramatic decrease in signal intensity because of magnetic susceptibility effects. T2*-weighted gradient echo and T2-weighted spin echo showed significant decrease in the signal intensity of normal lymph nodes at 24 hours after contrast injection at a dose of 1.7 mg Fe/kg. No significant changes in lymph node signal intensity on T1-weighted spin-echo images were noted at any dose or imaging time point. CONCLUSIONS: This preliminary clinical evaluation demonstrates intravenous delivery of an iron-based contrast agent, resulting in negative enhancement of normal lymph nodes.

Adult↗
PubMed1994

[Nontraumatic femoral head necrosis: classification of bone scintigraphic findings and diagnostic value of SPECT following planar imaging].

This study was conducted to determine bone scintigraphic findings in nontraumatic femoral head avascular necrosis and diagnostic value of SPECT imaging following a conventional planar imaging. Forty-three femoral heads in twenty-six cases with idiopathic femoral head necrosis (n = 2), systemic lupus erythematosus (n = 22), aplastic anemia (n = 1), and renal transplantation (n = 1) were studied. The diagnosis for femoral head necrosis was based on magnetic resonance imaging as well as other diagnostic studies in all cases. Scintigraphic findings of planar and SPECT images were classified into six categories: normal (N); cold or decrease (C); partial increase with cold or decrease (PH+C); ring-like increase with a cold center (RH+C); partial increase (PH); diffuse and/or irregular increase (DH). Avascular necrosis was confirmed in twenty-four femoral heads, in which planar and SPECT images showed scintigraphic findings of N (n = 3, 2), C (n = 1, 3), PH+C (n = 2, 8), RH+C (n = 2, 3), PH (n = 9, 2), and DH (n = 7, 6), respectively. Femoral heads without avascular necrosis demonstrated planar and SPECT findings of N (n = 16, 12), C (n = 0, 6), and DH (n = 3, 1), respectively. When considering C, PH+C, and RH+C as diagnostic findings for avascular necrosis, sensitivities of planar and SPECT images were 21% and 58%, and specificities were 100% and 68%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

Stereolithographic model construction from CT for assessment and surgical planning in congenital aural atresia.

Surgical planning for the treatment of congenital aural atresia has depended greatly on the use of high resolution computerized tomography (CT) and, recently, three-dimensional CT for visual representation of the complex anatomy associated with this condition. Computerized plastic model construction, stereolithography, allows the digital data obtained through CT scanning to produce a life-size anatomically accurate plastic model of the structure scanned. When this technique is applied to congenital aural atresia there is good bony surface rendering as well as complete representation of the deeper structures contained within the temporal bone, including the middle ear cleft, ossicular mass, and fallopian canal. The surgeon can use this model to augment imaging in becoming familiar with the patient's unique anatomy and to practice a planned surgical procedure.

Adolescent↗
PubMed1993

Head and neck: initial clinical experience with fast spin-echo MR imaging.

Fast spin-echo (FSE) is a new magnetic resonance (MR) imaging pulse sequence that employs echo trains of 180 degrees radio-frequency pulses to generate multiple refocused echoes during a single repetition-time interval. Phase encoding is reordered with the lowest spatial frequency views obtained in the echoes nearest the desired effective echo time. These techniques were used to examine 30 patients with pathologic conditions of the head and neck. The images were compared with closely matched conventional T2-weighted spin-echo (SE) images obtained during the same examination. Three unblinded readers evaluated 15 sets of both images for lesion conspicuity, motion artifact, diagnostic information, number of lesions seen, image quality, and sharpness of lesion borders. In all categories, FSE images were judged better than or equal to SE images, and in most cases FSE images were obtained in one-fourth to one-half the imaging time. In no case were lesions depicted on conventional T2-weighted SE images missed on FSE images; in fact, more lesions were seen on FSE images than on conventional T2-weighted SE images.

Adult↗
PubMed1993

Change induced by radiation therapy in FDG uptake in normal and malignant structures of the head and neck: quantitation with PET.

PURPOSE: To quantitate the changes induced in uptake of the glucose analog 2-[fluorine-18]fluoro-2-deoxy-D-glucose (FDG) in normal structures in the head and neck and compare these to the change in uptake in malignant structures in patients with head and neck tumors undergoing radiation therapy. MATERIALS AND METHODS: Eleven patients with biopsy-confirmed squamous cell carcinoma of the head and neck were studied before, during, and after a 6-week course of radiation therapy with positron emission tomography (PET)-FDG imaging. A ratio of FDG uptake in the structure compared with that in the cerebellum (termed metabolic ratio) within and outside of the field of radiation was determined in the adenoids; lingual and palatine tonsils; parotid, submandibular, and sublingual glands; and nasal turbinates, soft palate, and gingiva. RESULTS: The average metabolic ratio in the tonsils, nasal turbinates, soft palate, and gingiva did not change significantly with treatment. CONCLUSION: FDG uptake in normal structures does not change with radiation therapy. This fact is in marked contrast to the FDG uptake in squamous cell carcinomas in the head and neck, which decrease dramatically with treatment (P < .005).

Adenoids↗
PubMed1993

A novel megakaryocyte potentiator produced by MC-1 human lung cancer cell line.

The hematopoietic stimulating activity of a human lung cancer cell line, MC-1, was investigated. The protein fraction (MC-1 protein) was prepared from the serum-free culture supernatant of MC-1 cells using hydroxyapatite and concanavalin A-agarose columns. In serum-containing cultures, MC-1 protein stimulated colony formation by megakaryocyte colony-forming units (CFU), erythroid burst-forming units and granulocyte/macrophage (GM) CFU. The stimulating effect was strongest for megakaryocyte CFU. The factor having megakaryocyte colony-stimulating activity was shown to be a protein whose molecular weight was determined to be 23,000 daltons by gel filtration. By various analyses, this protein was shown to be molecularly different from the heretofore-identified cytokines that may affect megakaryocytopoiesis, i.e., interleukin-1 (IL-1), IL-2, IL-3, IL-6, IL-7, IL-11, granulocyte colony-stimulating factor (CSF), macrophage CSF, GM-CSF, leukemia inhibitory factor, stem cell factor and tumor necrosis factor. Under serum-free conditions, MC-1 protein augmented murine megakaryocyte colony formation in the presence of murine IL-3 and increased the acetylcholinesterase activity of purified murine megakaryocytes. It was also shown that MC-1 protein stimulated human megakaryocyte colony formation. It was concluded that MC-1 cells produce a megakaryocyte potentiator which is molecularly different from any heretofore-identified cytokines.

Animals↗
PubMed1993

Tetronothiodin, a novel cholecystokinin type-B receptor antagonist produced by Streptomyces sp. NR0489. I. Taxonomy, yield improvement and fermentation.

Streptomyces sp. NR0489 produces tetronothiodin, a novel brain-type cholecystokinin receptor antagonist. This species was differentiated from its related species S. gelaticus, S. griseolus and S. hydrogenans on the basis of their cultural characteristics, such as the utilization of carbohydrates and the presence or absence of various enzymatic activities. We applied the DNA-DNA hybridization method using photobiotin, which proved the genetic difference between the four species mentioned above. The yield improvement effort including single colony isolation, mutation, and protoplast regeneration together with medium optimization resulted in more than an 81-fold increase of the productivity of tetronothiodin as compared to that of the wild type strain.

DNA↗
PubMed1993

[In vitro study for hormones and growth factors dependent cell proliferation of endometrial adenocarcinoma cells].

Sex steroid hormone dependent cell proliferation and inducing growth factors of endometrial carcinoma cells were investigated using in vitro culture systems. The cell proliferation of Ishikawa cells derived from well-differentiated endometrial adenocarcinoma which possess both estrogen and progesterone receptors were stimulated by either estradiol added to culture media or EGF and TGF-alpha acting through EGF receptors. These stimulatory effects of TGF-alpha were antagonized by the anti TGF-alpha and EGF-receptor antibodies. The cell proliferations of other endometrial cancer cells were also inhibited by those antibodies. All endometrial cancer cells secrete TGF-alpha into their culture media measured by TGF-alpha ELISA methods. The expression of TGF-alpha mRNA and secretion of TGF-alpha of Ishikawa cells were induced by estradiol but not of hormone independent HEC-50 cells. Thus suggest that estradiol dependent growth factor should be TGF-alpha in human endometrial carcinoma cells.

Carcinoma, Endometrioid↗
PubMed1993

Magnetic resonance imaging-guided needle biopsy of head and neck lesions.

The Council on Scientific Affairs of the California Medical Association presents the following inventory of items of progress in otolaryngology-head and neck surgery. Each item, in the judgment of a panel of knowledgeable physicians, has recently become reasonably firmly established, both as to scientific fact and important clinical significance. The items are presented in simple epitome, and an authoritative reference, both to the item itself and to the subject as a whole, is generally given for those who may be unfamiliar with a particular item. The purpose is to assist busy practitioners, students, researchers, and scholars to stay abreast of these items of progress in otolaryngology-head and neck surgery that have recently achieved a substantial degree of authoritative acceptance, whether in their own field of special interest or another. The items of progress listed below were selected by the Advisory Panel to the Section on Otolaryngology-Head and Neck Surgery of the California Medical Association, and the summaries were prepared under its direction.

Biopsy, Needle↗
PubMed1993

[A case of frontal lobe syndrome followed by serial 123I-IMP SPECT].

Single photon emission computed tomography (SPECT) studies with N-isopropyl-p-[123I]iodoamphetamine (IMP) were performed in a 58-year-old man with frontal lobe syndrome. He had abulia and personality changes suggesting frontal lobe impairment. Six follow-up SPECT studies were conducted during 18 months from the onset. On the first scan, no abnormal pattern of regional cerebral blood flow (rCBF) was found. On the second scan, a mild reduction of rCBF was observed in bilateral frontal lobes. Through the third to sixth scans, a progressed reduction of rCBF in bilateral frontal lobes was confirmed by a semi-quantitative regions-of-interest analysis. Contrarily, abulia was improved, and personality change was not progressed during that period. Magnetic resonance imaging on admission revealed only a small subdural hematoma and high intensity areas in the right frontal lobe, which were resolved at the time of the sixth SPECT scan. It is suggested that rCBF studies by SPECT is not necessary concordant with psychiatric symptoms, and has possible limitations in pathophysiological evaluation for psychiatric disorders.

Amphetamines↗
PubMed1992

Comparison of Indium-111-labeled leukocyte scintigraphy and Technetium-99m joint scintigraphy in rheumatoid arthritis and osteoarthritis.

This study was undertaken to evaluate the use of Indium-111-labeled leukocyte (111In-WBC) imaging compared with Technetium-99m pertechnetate (99mTcO4-) imaging in 19 patients with rheumatoid arthritis (RA) and 8 with osteoarthritis. Knee and wrist joints were evaluated for both radionuclides. The results indicated a good correlation of the clinical assessment of pain and swelling with joint uptake ratio (JUR) between 111In-WBC and 99mTcO4- in RA and osteoarthritis patients. We observed a discrepancy in both imagings in "burned out" cases. It was concluded that a JUR of 111In-WBC could distinguish active RA from inactive RA or osteoarthritis at a value of 1.15 and that the use of 111In-WBC was a more reliable procedure than 99mTcO4-.

Adult↗
PubMed1992

Effects of transforming growth factors and regulation of their mRNA levels in two human endometrial adenocarcinoma cell lines.

The effects of the transforming growth factor-beta 1 (TGF-beta 1) and epidermal growth factor (EGF) on the growth of cells from 2 endometrial cancer lines, Ishikawa and HEC-50 were evaluated by measuring rates of DNA synthesis and changes in cell numbers during culture. EGF at 17 and 1.7 nM concentrations consistently enhanced HEC-50 cell proliferation. TGF-beta 1 inhibited Ishikawa cell proliferation but, unexpectedly for epithelium-derived cells, stimulated HEC-50 cell growth. This effect is of interest as it indicates that endometrial cells can acquire an altered responsiveness to a growth inhibitor during the process of malignant transformation. Northern blot analyses showed expression of TGF-alpha, TGF-beta 1 and EGF receptors mRNA in both cell lines. Neither estradiol (E2) nor 4-hydroxytamoxifen (OHTam) affected mRNA levels for either TGF-alpha or TGF-beta in HEC-50 cells, a line unresponsive to E2 for proliferation. In Ishikawa cells, previously shown to respond to both E2 and OHTam by increasing proliferation rates, E2 increased TGF-alpha mRNA and reduced TGF-beta mRNA levels. OHTam lowered the levels of both mRNA species, although the effect was greater on TGF-beta than TGF-alpha mRNA. These data are consistent with, but do not prove, the existence of a possible autocrine regulation by TGF-alpha and TGF-beta of human cancer cell proliferation, which might be under E2 influence in Ishikawa cells.

Adenocarcinoma↗
PubMed1992

Three-dimensional CT scan reconstruction for the assessment of congenital aural atresia.

Major advances in medical computer graphics workstations have provided the capability to produce high quality three-dimensional image reconstructions from conventional thin-section computerized tomography (CT) scans with the ability to observe the imaged structure from any angle, with views and dimensions that are comparable to actual dissections. We have applied this technique to the temporal bone to assess congenital aural atresia in surgical planning for hearing reconstruction in six patients. The digital information produced by thin-section CT scanning allowed for the re-creation of multiplanar reformatted, shaded surface, and volumetric images. With this technique the surface landmarks of the temporal bone were readily visualized, the configuration of the atretic plate and middle ear in relation to the tegmen and glenoid fossa could be precisely assessed and the structure of the ossicular mass was easily analyzed. Most significantly, the facial nerve could be accurately and easily envisioned in its entire intratemporal course. Three-dimensional imaging is a highly desirable means for observing CT scan data to facilitate the surgical planning for correction of congenital aural atresia.

Adolescent↗
PubMed1991

Transforming growth factor gene expression in human endometrial adenocarcinoma cells: regulation by progestins.

In an attempt to understand the antiproliferative effects of progestins in endometrial cancer, we have examined the effects of the potent progestin, medroxyprogesterone acetate (MPA), on the cell proliferation and the expression of transforming growth factor (TGF) alpha and beta genes in human endometrial adenocarcinoma cell lines. The two cell lines used were Ishikawa, var 1, and HEC-50. In addition, the effects of exogenous TGF-alpha and anti-epidermal growth factor (EGF) receptor monoclonal antibody on cell proliferation were determined. Incubation of both cell lines with MPA resulted in a time- and dose-dependent inhibition of cell proliferation. Half-maximal growth inhibition was observed at 0.6 nM. In Ishikawa cells, the relative abundance of TGF-alpha was significantly reduced by MPA. A significant decrease in TGF-alpha mRNA was apparent 6 h after exposure to MPA and a further decrease was seen 12-24 h after addition of the progestin. The concentration of TGF-alpha immunoreactivity in conditioned medium of MPA-treated cells was also significantly reduced compared to control cultures. MPA had no effect on TGF-alpha expression by HEC-50 cells. EGF mRNA was not detected by Northern blot analysis in either cell type. MPA had no significant effect on EGF receptor mRNA abundance but resulted in a small increase in EGF receptor number in Ishikawa cells. Anti-EGF receptor monoclonal antibody (0.6-6 nM) inhibited Ishikawa cell growth but had no effect on HEC-50 cell proliferation. Exogenous TGF-alpha stimulated proliferation of both cell lines, but Ishikawa cells were significantly more sensitive to exogenous TGF-alpha than HEC-50 cells. Furthermore, TGF-alpha could reverse the growth inhibitory effects of MPA on Ishikawa cells. A decrease in TGF-beta mRNA abundance was also observed in MPA-treated Ishikawa and HEC-50 cells. This effect was of small magnitude, variable, and only observed after prolonged exposure to MPA. These observations are consistent with the hypothesis that the antiproliferative effects of progestins on Ishikawa cells are mediated by decreased expression and autocrine action of TGF-alpha. Since similar growth inhibition is also seen in the HEC-50 cells in which progestins have no effect on TGF-alpha expression, additional mechanisms are likely to be involved in the antiproliferative effects of progestins in human endometrial cancer.

Antineoplastic Agents↗
PubMed1991

Isolation and analysis of the mouse genomic sequence encoding Cu(2+)-Zn2+ superoxide dismutase.

Cu(2+)-Zn2+ superoxide dismutase (SOD-1) is a ubiquitously synthesized eukaryotic enzyme with a variety of important roles in mammalian development and physiology. With the goal of better understanding the structure and regulation of this gene, we have cloned and analyzed the genomic structure of the mouse SOD-1 gene. The murine sequence has an intron:exon organization very similar to that of the human gene, though significant diversion was observed in the promoter and 3' regions. These differences account for the observation that only a single transcript for SOD-1 is seen in mouse cells, while two transcripts are derived from the human gene. The cloning of mouse SOD-1 should allow elucidation of the regulatory characteristics of this element, as well as new and informative genetic engineering experiments.

Amino Acid Sequence↗