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Biomedical subjects

N Kashiwagi

Publications and source records attributed to N Kashiwagi.

At least 37 records · Page 2Linked to original sources

Avascular necrosis and the Pavlik harness. The incidence of avascular necrosis in three types of congenital dislocation of the hip as classified by ultrasound.

We analysed the incidence of avascular necrosis in 101 hips of 90 infants with congenital dislocation treated with Pavlik harness and followed up for more than one year. Using ultrasonography in the flexed-abducted position the hips were classified as type A when the femora head was displaced posteriorly, but within the socket and making contact with the posterior inner wall of the acetabulum; type B when it was in contact with the posterior margin of the acetabulum, with its centre at this level or anterior to it; and type C when it was displaced out of the socket, with its centre posterior to the posterior rim of the acetabulum. Eighty-seven hips were reduced by the harness (86%), and seven of these developed avascular necrosis (8%). All 69 hips with type-A dislocation were reduced and only one (1.4%) showed slight avascular necrosis. Eighteen (78.3%) of 23 hips with type-B dislocation were reduced, and six developed avascular necrosis (33.3%). In one hip, the femoral head was severely damaged. None of the nine hips with type-C dislocation was reduced in the harness. We concluded that the Pavlik harness is indicated for type-A but not for type-B or type-C dislocations.

Contraindications↗

[Blood flow measurement of portal vein with fast cine phase contrast MR imaging under breath-holding].

Flow measurements of the right portal vein were performed in seven healthy volunteers with the segmented k-space fast gradient-echo phase-contrast (fcard-PC) sequence under breath-holding. The mean velocity and the flow rate of the right portal vein at maximal expiration, 14.3 +/- 4.4cm/sec and 457 +/- 218 ml/min, were significantly greater (p < 0.01) than those at maximal inspiration: 11.8 +/- 3.8cm/sec (mean +/- SD) and 364 +/- 191ml/min, respectively. Fcard-PC enabled flow measurements to be obtained under breath-holding. Using this technique, we demonstrated portal venous flow changes according to respiratory phase.

Adult↗

Genetic analysis of hydatidiform moles utilizing the oligonucleotide-DNA typing of the HLA-DRB gene.

The genetic origin of hydatidiform moles was analysed utilizing HLA-DNA typing. Using HLA-DR type-specific oligonucleotide probes, the DRB types of seven moles were determined and compared with the parental DRB types to determine the paternal and/or maternal origin of the moles. In four cases, the molar tissues showed single DRB types of paternal origin, although in one, the molar DRB type was also possessed by the mother. These four moles were, therefore, considered to be androgenetic in origin. Chromosomal karyotyping was carried out for three of these cases and confirmed the DR-DNA typing results. Two moles demonstrated a DRB-type triplet, which strongly suggested triploidy. Although one mole showed a heterozygous DRB type, karyotyping indicated triploidy (69, XXX) and suggested that this mole was caused by dispermy-fertilization, in which both of the sperms had the same DRB type. Although the majority (about 80%) of partial hydatidiform moles have been reported to be triploid as a result of dispermy, four of the moles analysed in this study (cases 1, 2, 3 and 4), diagnosed as partial macroscopically and/or histopathologically, were found to be androgenetic in origin using karyotyping and DR-DNA typing. Therefore, HLA-DR DNA typing, combined in some cases with karyotyping, provides an accurate method for diagnosing androgenesis and triploidy in complete and partial hydatidiform moles.

DNA Probes, HLA↗

Tissue transmigration of CZON (Cosmosin) to middle ear mucosa, maxillary sinus mucosa, and palatine tonsils.

The concentration of CZON was determined by HPLC in surgical patients with chronic otitis media, sinusitis, and tonsillitis. One gram of CZON was injected intravenously prior to surgery. The time course of the mean tissue CZON level was as follows: In the middle ear mucosa, 3.7 micrograms/g at 15 min, 7.2 micrograms/g at 30 min, and 2.9 micrograms/g at 1 hr (the half life: 21.3 min). In the maxillary sinus mucosa, 10.5 micrograms/g at 15 min, 11.8 micrograms/g at 30 min, and 2.8 micrograms/g at 1 hr (the half life: 17.5 min). In the tonsils, 14.9 micrograms/g at 15 min, 9.3 micrograms/g at 30 min, and 2.0 micrograms/g at 1 hr (the half life: 13.2 min). The concentration was high in the maxillary sinus mucosa and the tonsils, but was low in the middle ear mucosa. In the formers the transfer ratio reached its peak 15 to 30 min after administration, but in the latter the peak was reached 30 to 60 min after administration. The order of the transfer ratio at each region was above 25%. The tissue concentration exceeded the MIC80s of frequent isolates from these infections. CZON is considered to be a highly useful drug in the treatment of these infections.

Adolescent↗

Lymphocyte membrane modifications induced by HIV infection.

Novel carbohydrate antigen expressions were observed on T lymphocytes from HIV infected patients using flowcytometric analysis with four mAbs; BM-1, ACFH-18, FH-2 and C-6. These carbohydrate antigens were also expressed on oncogenic transformed cells but were either not expressed or were weakly expressed in lymphocyte populations from healthy subjects. A dramatic change in glycosylation was induced on CD8+T cells from HIV infected patients. The glycosylation change correlated with the progression of the disease. The incidence of Ley antigen expression on CD8+T cells increased as the disease progressed with the ongoing impairment of immune function. The phenotype change that occurred with Ley antigen expression might reflect the abnormal activation of T lymphocytes of some specific, but unknown, population of CD8+T cells. Thus, carbohydrate changes on the cell surface may induce immunological abnormality and accelerate the damage within the CD4+T cell subset, resulting in an impairment of the antigen specific immune system.

Adult↗

Phenotypic characteristics of bone marrow cells in patients with rheumatoid arthritis.

OBJECTIVE: Our previous study showed the presence of abnormal myeloid lineage cells in the epiphyseal bone marrow adjacent to joints affected with severe rheumatoid arthritis (RA). Now, we investigated whether there were any changes of other marrow cell populations related to RA, and whether there were any pathologically characteristic changes in the iliac bone marrow, which is one of the major systemic hematopoietic organs. METHODS: 2-Color flow cytometry was carried out to analyze the phenotypes of mononuclear cells (MNC) fractions in bone marrow aspirates and venous blood from 56 patients with RA and 7 non-RA controls. RESULTS: The absolute number of MNC in the iliac bone marrow was increased by 3-fold in the RA patients compared with the non-RA controls. In contrast, no significant increase of MNC was observed in the tibial epiphyseal bone marrow or peripheral blood. The ratio of each MNC fraction in the iliac bone marrow did not differ significantly between the RA patients and the non-RA controls. In lymphocyte subsets, the percentage of HLA-DR+CD8+ cells to all CD8 cells in the iliac bone marrow increased significantly in the RA patients compared with the non-RA controls. Abnormal myeloid cells (MX-GA+MY4+ cells), specific to severe RA, were found to be more concentrated in the iliac bone marrow than in the tibial epiphyseal bone marrow. CONCLUSION: Characteristic pathologic changes of the iliac bone marrow suggest an important role of systemic bone marrow in the progression of RA.

Adult↗

Polymerase chain reaction (PCR)/single-strand conformation polymorphism (SSCP) analysis of the human HLA-DQB regions.

Genetic diagnosis of 13 alleles of HLA-DQB1 (0501, 0502, 5031, 5032, 0601, 0602, 0604, 0201, 0301, 0302, 3032, 0401 and 0402) from 65 human DNA samples was achieved by applying single-strand conformation polymorphism (SSCP) analysis to DNA fragments amplified by the polymerase chain reaction (PCR) using a convenient primer set for DQB1 (recommendation of the International Histocompatibility Workshop, 1991). Differences between strand images (narrow/distinct or broad/diffuse) from the individual alleles and their electrophoretic mobilities are regarded as criteria for confirming the genetic diagnosis of DQB1 alleles. This primer set amplifies not only DNA fragments belonging to DQB1, but also to DQB2, and classification of 3 phenotypes (1.1, 1.2 and 1.1/1.2) in the presence of two alleles at the latter locus was suggested. Consequently, PCR/SSCP of DNA amplified by this primer enables classification of the phenotypes, at least under our experimental conditions, into 3 x 91 groups. Two advantages of SSCP analysis over VNTR with regard to the use of amplified DNA in forensic practice are described.

Alleles↗

Analysis of the HLA-DR gene frequencies in Japanese cases of juveniles rheumatoid arthritis and rheumatoid arthritis by oligonucleotide DNA typing.

HLA-DR gene frequencies in 59 Japanese children with juvenile rheumatoid arthritis (JRA) and 62 Japanese adults with rheumatoid arthritis (RA) were analyzed by oligonucleotide DNA typing. As in other studies, the frequency of DRB1*0405 in RA patients was significantly higher than in the Japanese controls. In a comparison of non-classified JRA patients with Japanese controls, no significant differences were observed in the frequency of DR types. However, when the JRA patients were classified into four clinical types, i.e., a rheumatoid factor-positive [RF(+)] polyarticular type, a rheumatoid factor-negative [RF(-)] polyarticular type, a pauciarticular type, and a systemic onset type, DRB1*0405 was found to be significantly higher in the RF(+) polyarticular JRA patients than in the controls (P < 0.05). Thus, the RF(+) polyarticular type of JRA had the same HLA association as RA. This result is consistent with the fact that both RF(+) polyarticular JRA and RA cases have a similar clinical course.

Adolescent↗

A single universal primer for the T-cell receptor (TCR) variable genes enables enzymatic amplification and direct sequencing of TCR beta cDNA of various T-cell clones.

We designed a primer for the PCR directed against a highly conserved sequence of the TCR V beta gene. The V beta-universal primer, in combination with a constant region-specific primer, enabled us to amplify TCR beta cDNA of allo-HLA class-II-reactive T-cell clones by PCR without prior knowledge of their V beta sequences. The amplified TCR cDNA was purified by agarose gel electrophoresis and subjected to direct sequencing. In nine of ten T-cell clones analyzed, direct TCR sequencing gave readable sequence ladders, including two-thirds of V beta, junctional, and J beta regions. One T-cell clone gave an unreadable mixed-profile sequence ladder, indicating that this clone expressed more than one major TCR beta transcript. Even in this case, however, it was possible to determine two different TCR beta sequences separately using sequence primers specific to one of the 13 J beta segments deduced from the mixed ladder. Thus, direct sequencing utilizing the single V beta-universal primer enabled a simple, rapid, and reliable sequence determination of TCR beta cDNA of all T-cell clones analyzed.

Amino Acid Sequence↗

Rapid DNA typing utilizing immobilized oligonucleotide probe and a nonradioactive detection system. Application to HLA-DR typing of the Japanese population.

We established a rapid and simple method of HLA-DR genotyping, and applied it for analysis of the Japanese population. Our method includes rapid preparation of DNA samples from buccal mucosa, incorporation of biotin-dATP into DRB genes during amplification by the polymerase chain reaction, hybridization with sequence-specific oligonucleotide (SSO) probes immobilized on nylon membranes via poly (dT) tails, and detection of the hybridization signal as chemiluminescence. We carried out DR typing of 30 Japanese donors using 20 different immobilized SSO probes, and obtained unambiguous typing signals showing perfect correlation with their serologic DR types. The genotyping also enabled us to identify several DR types unique to the Japanese population, such as DRw12b (DRB1*1202), DRw14c (DRB1*1405), and serology blank type, DR'JX6' (DRB1*1403). The method presented here would be suitable for routine DR typing in tissue-typing laboratories.

Base Sequence↗

Effect of oligomers of ethylene glycol on thermotropic phase transition of dipalmitoylphosphatidylcholine multilamellar vesicles.

The effect of oligomers of ethylene glycol (EG) on thermotropic phase transitions of dipalmitoylglycerophosphatidylcholine multilamellar vesicles (DPPC-MLV) were investigated. Diethylene glycol (di-EG) had a biphasic effect on transition temperature, reducing pre-transition temperature (Tp) at low concentrations but increasing main transition temperature (Tm) and extinguishing pre-transition at high concentration. Results of the X-ray diffraction method and the excimer method indicated that di-EG induced interdigitated gel phase (L beta 1 phase) in the DPPC membranes at high concentration. Phase diagram of temperature-di-EG concentration for DPPC-MLV was determined by use of X-ray diffraction and differential scanning calorimetry, which was similar to that of temperature-EG concentration. The minimum concentration of di-EG where L beta 1 phase was induced was 42%(w/v), which was larger than that of EG (30%(w/v)). On the other hand, in the presence of triethylene glycol (tri-EG), Tm and Tp increased with an increased in tri-EG concentration, as well as poly(ethylene glycol). These differences, between the effects of di-EG and those of tri-EG, might be due to the differences of their sizes.

1,2-Dipalmitoylphosphatidylcholine↗

Linkage between HLA-DRB1 and -DRB3 types in the Japanese population analyzed by oligonucleotide genotyping.

We analyzed linkage between HLA-DRB1 and -DRB3 types in 219 Japanese donors by oligonucleotide genotyping. In the Japanese population, DRB1*1201 was linked with DRB3*0101 in all donors analyzed; in contrast, most Caucasian DRB1*1201 is known to be linked with DRB3*02(01/02) (*0201 or *0202). However, most DRB1*1202 was linked with DRB3*0301. Thus, the two DRw12-related DRB1 types are linked with DRB3 types distinct from each other. All the three DRw14-related DRB1 types, DRB1*1401, DRB1*1402, and DRB1*1405, were linked with DRB3*02(01/02) in the Japanese population, contrasting with the known linkage between DRB1*1402 and DRB3*0101 in other ethnic populations. The serologically "blank" DR type, DRB1*1403, was linked with DRB3*0101. Other DRB1 types, DRB1*0301, DRB1*11(01/04) (*1101 or *1104), and DRB1*13(01/02) (*1301 or *1302) in the Japanese population were linked mostly with the same DRB3 types, like those known in other ethnic populations.

Alleles↗

Phase transitions of phospholipid vesicles under osmotic stress and in the presence of ethylene glycol.

The effects of poly(ethylene glycol) (PEG) on the phase transition of phospholipid multilamellar vesicles (MLVs) were investigated by using differential scanning calorimetry (DSC). Main transition temperature (Tm) and the pre-transition temperature (Tp) of neutral phospholipid-, DMPC-1, DPPC- and DSPC-MLVs increased with an increase in PEG concentration. The subtransition temperature of DPPC-MLV also increased with an increase in PEG concentration. These results could be qualitatively explained by enhancement of the lateral packing on the basis of the osmoelastic coupling theory. The pretransition temperature increased faster than the main transition temperature did with an increase in PEG concentration. The increment of Tm depended on the hydrocarbon chain length, the shorter the hydrocarbon chain length was, the larger the increment was. The transition width in the DSC peak was broadened with an increase in PEG concentration. These three above-mentioned effects are the main differences between the effects of the osmotic stress on the phase transition of MLVs and those of hydrostatic pressure. On the other hand, ethylene glycol (EG), which is the monomer of PEG, had a biphasic effect on transition temperature of DPPC-, DSPC-, and DMPC-MLV, reducing Tm and Tp at low concentrations, but increasing Tm and extinguishing pretransition at high concentrations. This is explained by the induction of an interdigitated gel phase at high concentrations of EG, which indicates that EG can easily penetrate into the head group region of the lipid, in contrast with PEG 6K, because EG is small. Temperature-EG concentration phase diagrams for the various PC-MLVs were determined.(ABSTRACT TRUNCATED AT 250 WORDS)

Calorimetry, Differential Scanning↗

Analysis of HLA-DR types of unexplained recurrent spontaneous aborters in the Japanese population by oligonucleotide-DNA typing.

To examine whether unexplained recurrent spontaneous abortion (URSA), defined as 2 or more consecutive spontaneous abortions, is correlated with a particular DR type in the Japanese population, we determined the HLA-DR types of 82 primary aborters and 21 secondary aborters by DNA typing utilizing the polymerase chain reaction (PCR) and hybridization with sequence-specific oligonucleotides (SSOs). The DR gene frequencies of the patient group were compared with those of a normal group at three different levels of DR-definition (27, 13 and 11 DR types). At none of the three levels of comparison was any particular DR type with a frequency differing significantly between the patient and normal groups detected in Japanese URSA patients. Furthermore, we examined whether URSA was correlated with the degree of compatibility of HLA-DR antigen within patients and their husbands. Comparison of the DR compatibility between patients and normal couples was made in two different ways, i.e., comparison of the numbers of couples with mismatches and comparison of the average number of mismatches. For either of these two comparisons, we observed no difference in DR compatibility between patients and normal couples. Our results suggest that URSA is not correlated with any particular DR type and that the condition cannot be explained simply by DR compatibility between husband and wife.

Abortion, Habitual↗