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S Date

Publications and source records attributed to S Date.

16 recordsLinked to original sources
PubMed1998

[Diagnosis of intraductal spread of breast cancer by high-resolution MR imaging: correlation between MR imaging and pathohistological findings].

The main purpose of this study was to investigate pathohistological factors that affect the MR findings of intraductal spread (IDS) of breast cancer. The subjects of the present study were 42 breast cancer patients who were examined by MR imaging. Fat-suppressed high-resolution T1-weighted spin-echo images [350/13/1 (TR/TE/excitations), 16-cm FOV, 5-mm section thickness, and 512 x 256 matrix] were obtained one minute after the intravenous administration of Gd-DTPA. In this protocol, contrast determination time was 1 min 48 sec. Of the 42 cases, IDS was found to be located more than 1 cm from the primary focus in 22 cases (52%). Rates of sensitivity, specificity and accuracy of MR imaging for the detection of IDS were 82%, 80%, and 81%, respectively. The probable cause of misdiagnosis was parenchymal enhancement due to severe fibrocystic disease and normal menstrual cycle. In 21 of 42 cases, the MR findings were precisely correlated with the pathohistologic findings of almost the same cross-section. The MR findings of IDS varied greatly with observation of linear, band-like, branch-like, plate-like and minute ring enhancements. These findings closely reflected the size, aggregation pattern, and distribution of intraductal lesions. In particular, minute ring enhancement was only observed in 4 comedo-type lesions. This pattern of enhancement is considered to reflect elevated intraductal cellular density with necrosis in the central region.

Adult↗
PubMed1996

Thoracic aortic aneurysm and aortic dissection: new endoscopic mode for three-dimensional CT display of aorta.

Three-dimensional (3D) endoscopic-mode software was used at helical computed tomography (CT) to evaluate distal aortic arch aneurysms (n = 12) and aortic dissections (n = 10); images were compared with two-dimensional (2D) axial source images. In distal aortic arch aneurysms, the 3D endoscopic mode depicted the relationship of the arterial orifices and the aneurysm, which is difficult to evaluate with 2D axial images alone. In aortic dissections, however, the 3D endoscopic mode did not provide additional information to that provided on the 2D axial source images.

Aged↗
PubMed1993

Multiple alignment of sequences on parallel computers.

A software package that allows one to carry out multiple alignment of protein and nucleic acid sequences of almost unlimited length and number of sequences is developed on C-DAC parallel computer--a transputer-based machine. The farming approach is used for data parallelization. The speed gains are almost linear when the number of transputers is increased from 4 to 64. The software is used to carry out multiple alignment of 100 sequences each of alpha-chain and beta-chain of hemoglobin and 83 cytochrome c sequences. The signature sequence of cytochrome c was found to be PGTKMXF. The single parameter, multiple alignment score, S, has been used to categorize proteins in different subfamilies and groups.

Algorithms↗
PubMed1992

Cleavage of hexokinase II to two domains by trypsin without significant change in catalytic activity.

Hexokinase II prepared from Ehrlich-Lettre hyperdiploid tumor cells (ELD cells) was subjected to a limited digestion by trypsin. After 60 min digestion, hexokinase II (100 kDa) was completely cleaved to two fragments with the molecular weight of about 60 kDa and 40 kDa as manifested in SDS-PAGE. It was noteworthy that the enzyme activity was observed even at the time when the native enzyme molecule was no more detectable. These fragments were separated by SDS-PAGE irrespective of the presence of a reducing agent, but neither by native PAGE nor by cellulose acetate membrane electrophoresis under the nondenaturing conditions. Neither kinetic parameters such as Km values for ATP and glucose nor an ability of binding to mitochondria were changed significantly by the tryptic digestion. These results indicate that an essential conformation of hexokinase II can be restored by the self-association of two fragments produced as a result of the cleavage by trypsin at the middle of the molecule. Affinity labeling with 2',3'-dialdehyde ATP followed by the trypsin digestion showed that ATP binding site resided in the 40 kDa fragment. Furthermore, the mode of the response in the incorporation of this ATP analog to hexose phosphate, moreover, was similar to that in the catalytic activity.

Animals↗
PubMed1992

Activity and distribution of phosphoinositidase C in rat sciatic nerve.

The hydrolysis of phosphatidylinositol-4,5-bisphosphate (PIP2) by rat sciatic nerve cytosolic phosphoinositidase C [phosphoinositide-specific phospholipase C (PIC)] was studied at neutral pH and at ionic concentrations that approximate intracellular conditions. The principal water-soluble product formed was shown to be inositol trisphosphate by anion exchange chromatography. The maximum hydrolysis rate (2.5 nmol/min/mg protein) was achieved at less than 100 nM Ca2+. Hydrolysis was markedly increased to 15 nmol/min/mg protein by inclusion of K+ in the reaction mixture. In the presence of 200 mM K+, the optimum Ca2+ was increased to approximately 600 nM. Higher Ca2+ concentrations progressively inhibited PIP2 hydrolysis. Mg2+ also inhibited the reaction, but the presence of equimolar amounts of ATP and Mg2+ had no effect. Appreciable degradation of phosphatidylinositol-4-phosphate (PIP) also occurred in the nanomolar Ca2+ range, whereas breakdown of phosphatidylinositol (PI) required millimolar Ca2+. The presence of PIP but not PI inhibited PIP2 hydrolysis. Upon subcellular fractionation of nerve, more than 50% of recovered PIC activity was in the cytosol and about 20% was located in a myelin-enriched fraction. Using PIP2 as substrate, PIC activities in nerves from normal and streptozotocin-induced diabetic animals were not different. However, the myelin-associated enzyme from diabetic animals was more labile to freezing and thawing.

Animals↗
PubMed1987

Cloning and characterization of Streptococcus mutans LM7 plasmid pAM7.

The 5.6-kilobase-pair cryptic plasmid, pAM7, of Streptococcus mutans LM7 was cloned into Escherichia coli plasmids or a shuttle plasmid to examine whether the plasmid encodes bacteriocin. Plasmid pAM7 encoded proteins with molecular weights of 30,000, 22,000, and 12,000, but none of them appeared to be bacteriocin.

Bacterial Proteins↗
PubMed1986

Immune complex containing herpesvirus antigen in a patient with acute retinal necrosis.

A 21-year-old man with acute retinal necrosis showed a marked increase in the convalescent titer to herpes simplex type 1 virus, especially in the aqueous humor obtained by anterior chamber paracentesis. Using an enzyme-linked immunosorbent assay, we tried to detect the herpesvirus antigen in the circulating immune complex obtained from this patient. The immune complex contained an antigen or antigens that reacted with antiherpes simplex type 1 antibody.

Acute Disease↗
PubMed1980

A survey of 3,000 examinations by transrectal ultrasonotomography.

As a routine examination for intrapelvic organs, transrectal ultrasonotomography was performed 3,000 times on 2,331 patients from June 1976 to February 1980. In this series, 57 patients were diagnosed as prostatic cancer by transrectal ultrasonotomography and 54 (94.7%) of them were finally diagnosed as cancer by biopsy. Three hundred twenty-six patients were diagnosed as suspected prostatic cancer, and cancer was confirmed also by biopsy in 12 (3.7%) of them. Among 1,741 patients with various prostatic diseases on whom cancer was ruled out by transrectal ultrasonotomography, there were 2 (0.1%) false-negative cancer cases.

Adolescent↗
PubMed1979

Ultrasonic real-time guidance for percutaneous puncture.

Real-time scanning was applied to the sonically guided puncture technique. A special puncture attachment connected to the ultrasound sector scanner was developed for this purpose. A puncture needle is introduced into the scanning plane through the canal in the attachment. Excellent real-time images of both the target lesion and the needle can be clearly seen on the oscilloscope during the puncture procedure. Puncture not only for cystic structures but also for solid masses can be made easily and safely by this new technique. Successful applications of the technique have been carried out for renal cyst puncture, percutaneous antegrade pyelography, percutaneous nephrostomy, percutaneous renal biopsy, and perineal prostatic biopsy.

Kidney Diseases↗