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Biomedical subjects

Y Horiuchi

Publications and source records attributed to Y Horiuchi.

At least 37 records · Page 2Linked to original sources
PubMed2000

Measurement of serum low density lipoprotein-cholesterol in patients with hypertriglycemia.

Low density lipoprotein-cholesterol (LDL-c) concentration measured by a homogeneous enzymatic assay was reported to correlate well with the modified beta-quantification assay, especially in samples with high triglyceride (TG) concentration. In this study, we evaluated a homogeneous enzymatic assay, Cholestest-LDL assay system, in hypertriglycemic patient samples, and found that 56% (9/16) of serum samples with intermediate TG concentrations (2.27-4.52 mmol/L) showed more than 10% discrepancy with concentration by the modified beta-quantification assay. Such serum samples originated from patients with hyperglycemia of type II a (three cases), type II b (two cases), type III (one case), and type IV (six cases). Differential staining of cholesterol and triglyceride after agarose gel electrophoresis revealed that these serum samples contained significant amounts of intermediate fractions between pre-beta- and beta-lipoproteins. Since lipoprotein (a), which migrates between pre-beta- and beta-lipoproteins, is not correlated with the discrepancy, we believe the intermediate fraction consists of intermediate density lipoprotein (IDL) and a chylomicron remnant. A part of IDL and chylomicron remnant, which contain a significant amount of triglyceride, might be measured as LDL-c by the homogeneous enzymatic assay, but not by the modified beta-quantification assay.

Cholesterol, LDL↗
PubMed2000

Evaluation of the applicability of the bacterial endotoxin test to antibiotic products.

Fundamental conditions for applying the bacterial endotoxin test to antibiotic products were investigated so as not to affect the level of regulation by the rabbit pyrogen test. According to accuracy evaluation of test methods, the kinetic-turbidimetric and kinetic-colourimetric assays were shown to allow more accurate measurement and, therefore, more sensitive detection of interference to the bacterial endotoxin test than the gel-clot method. In total, 102 antibiotic products were evaluated on their interfering effect to show that the antibiotics could be categorized into three groups depending on intensity of the interference. Although the test was shown to be applicable even to the group showing the strongest interference, it was assumed to be crucial to use appropriate reagents and an accurate test method for avoiding approval of a pyrogenic product. Accordingly, lists of antibiotics are presented to provide limits of concentration for eliminating interference and endotoxin limits for approval to facilitate effective bacterial endotoxin tests.

Animals↗
PubMed2000

Difficulties in treating steroid withdrawal: intermittent ACTH and low dose systemic cyclosporin used to treat a senile erythroderma patient.

The tapering or termination of prolonged strong topical and/or systemic corticosteroid application for extensive generalized eczema has adverse effects on the body and thus presents a very difficult situation. The present case is that of a 68-year-old man with erythroderma following eczema, whose steroid withdrawal was successfully treated with intermittent ACTH and low dose systemic cyclosporin administration over a period of one year.

Adrenocorticotropic Hormone↗
PubMed2000

Myxomatous granulation as a feature of a subcutaneous pseudotumor.

This paper presents myxomatous granulation in the sacral area as a feature of a pseudotumor. The patient was an 86-year-old male with a pseudotumor in the sacral area that may possibly have been the result of prolonged bed confinement. The initial diagnosis was lipoma. Specimen examination disclosed granulation tissue with inflammatory mixed cellular infiltrates undergoing myxomatous change. Plasma cell infiltrates were frequently present.

Aged↗
PubMed2000

Normal kinematics of the interosseous membrane during forearm pronation-supination--a three-dimensional MRI study.

We studied in vivo dynamic shape changes of the interosseous membrane (IOM) during forearm rotation using three-dimensional magnetic resonance imaging (3D-MRI), and simultaneously analysed 3D-motion of the forearm rotation. Wavy deformities were seen in the IOM in the pronated position, and similar small changes were also seen at maximum supination (average 82 degrees ) and in the neutral position. These dynamic changes mainly occurred in the membranous part of the IOM, whereas the tendinous part demonstrated minimal dynamic changes during rotation in all subjects. On the dorsal aspect, deformity around the dorsal oblique cord was seen at maximum pronation. From this 3D-MRI observation, the tendinous part is considered to be taut during rotation to provide stability between the radius and ulna, because of its straightness and less dynamic changes. The more deformable membranous part is important to allow for smooth rotation, since it lies at a distance from the rotation axis. Inelasticity developing in the membranous part from trauma may pre-dispose to pronation-supination contracture. The radius rotated around the ulna from maximum supination to 45 degrees pronation. At maximum pronation (average 75 degrees ), the radius translated average 1.8 mm palmarly and rotated average 4.0 degrees ulnarward on the ulna. Incongruity of the distal radioulnar joint, contraction of the pronator quadratus and torsion between the radius and ulna at maximum pronation may produce this irregular motion of the radius and cause the dynamic changes of the IOM.

Adult↗
PubMed2000

[Protective efficacy of BCG Tokyo 172 in the guinea pig model of pulmonary tuberculosis].

BCG Tokyo 172 strain was examined for its protective efficacy against pulmonary tuberculosis in a guinea pig model. Guinea pigs were vaccinated with an intradermal injection of 10(3) CFU of BCG Tokyo 172 strain. BCG Copenhagen 1331 was employed as a control strain. Eight weeks after the vaccination, the animals were infected with about 10 CFU of M. tuberculosis H37Rv by a respiratory route in an aerosol chamber. Five weeks after infection, the animals were euthanized and their spleens, lungs and livers were obtained for enumeration of M. tuberculosis H37Rv and histopathological examinations. The mean log10 CFU of M. tuberculosis H37Rv recovered from right lower lung lobes of guinea pigs vaccinated with BCG Tokyo 172 (frozen), BCG Tokyo 172 (freeze-dried), BCG Copenhagen 1331 (freeze-dried) and placebo were 4.72, 4.23, 4.35 and 5.76, respectively. The mean log10 CFU of the bacteria recovered from spleens were 2.11, 1.51, 1.37 and 5.90, respectively. There was a significant difference in bacterial recovery from both lung and spleen between the vaccinated and the non-vaccinated groups. No significant difference was seen among the groups vaccinated with different strains of BCG in any organ. The lungs exhibited just small granulomatous nodules and the spleens showed no granulomatous nodules in the BCG-vaccinated guinea pigs. On the other hand, the lungs and spleens from non-vaccinated guinea pigs showed much larger granulomatous nodules with central necrosis. These histopathological difference between the vaccinated and the non-vaccinated guinea pigs was consistent with the difference of bacterial growth between them. The results of this study have clearly indicated that BCG Tokyo 172 strain possesses a significant protective efficacy against M. tuberculosis as well as BCG Copenhagen 1331 strain. These results have also shown that the respiratory infection model in guinea pigs is very useful to evaluate efficacy of vaccines against pulmonary tuberculosis.

Animals↗
PubMed2000

[The Endotoxin 10,000 Reference Standard of the National Institute of Health Sciences (the Japanese Pharmacopoeia Endotoxin 10,000 Reference Standard) (Control 0001)].

To establish the fourth lot (Control 0001) of the Endotoxin 10,000 Reference Standard of the National Institute of Health Sciences (the Japanese Pharmacopoeia Endotoxin 10,000 Reference Standard), a candidate standard (CS) was prepared and then evaluated. The potency of the CS was assayed against USP Endotoxin Reference Standard (Lot G-1) and defined as containing approximately 20,000 endotoxin units (EU) per vial by a collaborative study in which 5 laboratories participated. Based on the results, the CS was authorized to be the fourth lot of the Endotoxin 10,000 Reference Standard containing 20,000 EU per vial.

Endotoxins↗
PubMed1999

A 58-kDa Shc protein is present in Xenopus eggs and is phosphorylated on tyrosine residues upon egg activation.

A 58-kDa protein was detected in Xenopus egg lysate by SDS-PAGE and immunoblotting with an antibody raised against adaptor protein Shc, a well known tyrosine kinase substrate in numerous biological events. Tyrosine phosphorylation of the Xenopus Shc protein (p58 xShc) was found to increase 2.3 +/- 0.4-fold (n = 3) upon fertilization. Pretreatment of eggs with the tyrosine kinase inhibitor genistein effectively blocked the fertilization-dependent phosphorylation. Tyrosine phosphorylation of p58 xShc was also observed when eggs were activated parthenogenetically by an integrin-interacting RGDS-peptide which is known to cause egg activation accompanied by intracellular calcium release. On the other hand, other egg-activating treatments such as electrical shock and calcium ionophore, which directly induce the elevation of intracellular calcium, did not show such an effect. It is also suggested that the phosphorylated p58 xShc may play a role unique to the egg activation process because we found that there was no increase of Shc-Grb2 complex after fertilization. These results demonstrate that p58 xShc is a substrate of egg tyrosine kinases which may be activated by sperm-egg interaction and suggest that the phosphorylated p58 xShc may act upstream of the calcium-dependent pathway of egg activation.

Adaptor Proteins, Signal Transducing↗
PubMed1999

Fat suppression magnetic resonance imaging of the triangular fibrocartilage complex. Comparison with spin echo, gradient echo pulse sequences and histology.

Magnetic resonance imaging (MRI) of the triangular fibrocartilage complex (TFCC) of the wrist was performed in ten healthy volunteers using spin echo T1-weighted (SE-T1), fast spin echo T2-weighted (FSE-T2), gradient echo T2-weighted (GRE-T2) and fat suppression spin echo T1-weighted (FS-T1) images. The images were obtained in the coronal plane and were compared to the corresponding histological coronal sections obtained from five fresh frozen cadavers. In our analysis, the FS-T1 pulse sequence visualized the details of the TFCC best, followed by the GRE-T2 images. Delineation of the TFCC on the SE-T1 and the FSE-T2 was poor. The coronal morphology of the TFCC represented on the fat suppression image was almost identical to the corresponding histological sections. We conclude that the fat suppression MRI clearly shows the complex structure of the TFCC and is useful for the morphological evaluation of the TFCC.

Adult↗
PubMed1999

In vivo motion analysis of forearm rotation utilizing magnetic resonance imaging.

OBJECTIVE: To analyse in vivo normal forearm rotation utilizing the image processing method on axial magnetic resonance imaging. DESIGN: Rotatory motion and translation of the radius and rotation of the ulna were analysed in vivo, utilizing features of the bone image; axial centre of gravity and axis of the bone. METHODS: Axial magnetic resonance images at the proximal, middle and distal portion of the right forearms of 20 healthy volunteers were examined in five rotational positions, maximum pronation, 45 degrees pronation, neutral, 45 degrees supination and maximum supination. The axis of forearm rotation, the rotation angle of the radius, the rotation of the radius around its axial centre of gravity, and the rotation of the ulna around its axial centre of gravity were calculated on these axial MR images. RESULTS: The radius rotates in a near-circular ellipse around its rotational centre located on a line through the radial head and the ulnar head from maximum supination to 45 degrees pronation. There was discrepancy between the calculated maximum rotational angle of the radius and the pronation-supination angle showed on the goniometer. This discrepancy was due to motion at the radiocarpal, midcarpal and carpometacarpal joints. The rotation of the ulna ranges within 6 degrees. At maximum pronation, there was palmar translation of the radius. CONCLUSIONS: The forearm rotation is not a simple rotatory motion but a complex motion with rotation and translation. The palmar translation of the radius at maximum pronation may be caused by incongruity of the distal radioulnar joint and contraction of the pronator quadratus muscle. RELEVANCE: To date there exist few methods for the accurate and non-invasive assessment for motion analysis of the forearm rotation. Such a technique utilizing magnetic resonance image characteristics is, however, helpful to reveal accurate self- and relative-rotatory motion of both radius and ulna as well as the translation movement on forearm rotation in normal forearm.

Adolescent↗
PubMed1999

Three-dimensional magnetic resonance imaging of the interosseous membrane of forearm: a new method using fuzzy reasoning.

We now report newly developed three-dimensional magnetic resonance imaging (3D-MRI) system which is based on semiautomatic tissue extraction from the axial MR images utilizing the fuzzy reasoning calculation method and 3D-image reconstruction with surface rendering. We also studied normal in vivo dynamic changes of the interosseous membrane (IOM) of forearm during rotation using this 3D-MRI. Serial axial MRI of right forearms of five healthy volunteers was obtained in five rotational positions, and extraction and 3D-reconstruction of the radius, ulna, and IOM was made using the system. Extraction results were well with the fuzzy reasoning method. 3D-MRI of the radius and ulna, IOM were reconstructed from these images respectively, and their 3D-shapes were almost identical to the anatomic shape. 3D-MRI showed there were wavy deformities on the IOM in pronation position in the all five subjects and dorsiflexion on the most dorsal portion of the IOM at maximum supination in three forearms. In neutral position, the IOM of all five volunteers was almost flat. From anatomic orientation, these dynamic changes of the IOM mainly occurred at the membranous portion, which is soft, thin, and elastic. Otherwise, the tendinous portion which is a thick and strong complex of 5 to 10 bundles run from proximal one third of the radius to distal one fourth of the ulna, demonstrated minimal dynamic changes on the 3D-MRI. Therefore, the tendinous portion is considered to be taut during rotation to provide stability between the radius and the ulna, while the membranous portion is easy to deform and allowing smooth rotation. Furthermore, because of wide-use, our 3D-MRI system is useful for in vivo analysis of soft tissue kinesiology in normal and abnormal musculoskeletal systems.

Adult↗
PubMed1999

In vivo MR studies of dynamic changes in the interosseous membrane of the forearm during rotation.

In vivo dynamic changes in the interosseous membrane (IOM) during forearm rotation were studied using magnetic resonance imaging (MRI). The right forearms of 20 healthy volunteers were examined in five different rotational positions. Axial slices were obtained at the proximal quarter, the middle and the distal quarter of the forearm. The changes in shape of the IOM during rotation were observed in an axial MR plane. For each image, we measured the interosseous distance and the length of the interosseous membrane. Images of the tendinous and membranous parts of the IOM could be differentiated by thickness. There were minimal dynamic changes in the tendinous part on the MRI while the membranous part showed numerous changes during rotation. The interosseous distance and the length of the interosseous membrane were maximum from a neutral to a slightly supinated position. The tendinous part is considered to be taut during rotation to provide stability between the radius and the ulna, but the membranous part which is soft, thin and elastic, allows smooth rotation.

Elasticity↗
PubMed1999

Dynamic changes in the shape of the triangular fibrocartilage complex during rotation demonstrated with high resolution magnetic resonance imaging.

We studied in vivo dynamic changes in the triangular fibrocartilage complex (TFCC) in ten healthy volunteers using high-resolution magnetic resonance imaging (MRI). A custom made surface coil, which was specially designed to allow movements of the wrist in all directions, was used in this study. MR images in the axial and coronal planes were acquired at maximum pronation, in the neutral position and at maximum supination. During pronation and supination, little deformity of the disc proper was seen on axial sections. In contrast, the ulnar side of the TFCC around the ulnar styloid process showed obvious dynamic changes. The ulnar head translated palmarly to the radius in supination and dorsally in pronation, while there was little change in the position of the fovea of the ulna in relation to the radius. Considering the three-dimensional structure of the TFCC, these findings suggest that the disc proper is strong enough to support the ulnar carpus with little deformity during rotation and that the triangular ligament twists at its origin. During rotation there is friction between the proximal side of the disc proper and the ulnar head. On coronal sections, the disc proper became thinner in pronation due to increased ulnar variance.

Adult↗