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H Honda

Publications and source records attributed to H Honda.

At least 73 records · Page 4Linked to original sources
PubMed2001

Successful diagnosis of fetal gender using conventional PCR analysis of maternal serum.

BACKGROUND: Fetal DNA has been found in maternal plasma and serum. Diagnosis of fetal gender using maternal plasma and serum has been attempted in an effort to develop a new noninvasive method of prenatal diagnosis. METHODS: Peripheral blood samples were obtained from 61 pregnant women at 10-17 weeks of gestation before amniocentesis. DNA was extracted from 800 microL of each plasma or serum sample. To detect the Y-chromosome-specific sequences DYS14 and DYZ3 in the maternal plasma and serum, 40 cycles of PCR were carried out for each DNA extract. The PCR products were analyzed by 2.5% agarose gel electrophoresis and ethidium bromide staining, and the results were compared with the results of the cytogenetic analyses of amniocentesis. RESULTS: Cytogenetic analysis of amniocentesis revealed that 31 pregnant women had a male fetus and the remaining 30 pregnant women had a female fetus. Both DYS14 and DYZ3 were detected in 27 of the 31 plasma samples obtained from pregnant women carrying a male fetus and in all of 31 serum samples obtained from the same women. Neither DYS14 nor DYZ3 was detected in either the plasma or serum samples obtained from any of the 30 pregnant women carrying a female fetus. CONCLUSION: PCR analysis of maternal serum can be used to diagnose fetal gender.

DNA↗
PubMed2001

[Multislice CT of the abdomen].

With the advent of multislice CT, temporal and spatial resolution has been dramatically improved, enabling multi-phase dynamic CT of the abdomen with very thin slices. The image quality of multiplanar reconstruction (MPR) and CT angiography (CTA) has been markedly improved. These high-quality dynamic CT, MPR, and CTA images are an advantage of multislice CT of the abdomen. The CT protocol is very important in obtaining such high-quality images, and knowledge of the relation between the contrast medium and enhancement of each organ is essential. In this article, we present our multislice CT protocol for the abdomen as well as the results of our investigation using time-density-curve analysis. The clinical usefulness of MPR images and CTA of the abdomen are also discussed.

Contrast Media↗
PubMed2001

[A case of Sjögren's syndrome presenting with hypokalemic myopathy due to renal tubular acidosis].

A 37-year-old woman was admitted to our university hospital because of severe flaccid quadriplegia. Her laboratory data, lip biopsy and muscle biopsy findings were compatible with hypokalemic myopathy due to renal tubular acidosis(RTA) type I associated with primary Sjögren's syndrome. Kidney biopsy revealed chronic tubulointerstitial nephritis(TIN), consisting of focal mononuclear cell infiltration with tubulitis, interstitial fibrosis and tubular atrophy. Immunohistochemical analysis of the renal biopsy specimens showed that the infiltrating mononuclear cells were predominantly CD8+T cells, and CD68+ cells(macrophages), whereas CD4+ T cells were fewer in number. Following potassium administration and alkali therapy, hypokalemia and metabolic acidosis were ameliorated and limb palsy gradually subsided. Finally, RTA improved with prednisolon and short term cyclophosphamide treatment without supplemental potassium and alkali therapy.

Acidosis, Renal Tubular↗
PubMed2001

[Dynamic MR imaging of the upper abdomen: timing optimization and pulse sequence selection].

Since breath-hold gradient-echo MR imaging was introduced, dynamic MR study has played an important role in the MR investigation of the upper abdomen. In this article, the importance of tailoring imaging delay in each individual patient is stressed, with special attention given to a logical aspect of setting delay time based upon the bolus transfer time obtained by test injection. Also discussed is the importance of selecting types and parameters of pulse sequence to maximize the enhancement effect. It should be noted that alteration of gadolinium concentration in vivo following intravenous injection could result in a large change in signal intensity change on one sequence but little change on another. Double-dose 3DFISP with tailored delay time utilizing the test injection method, which is currently used for dynamic MR imaging in our institute, is presented.

Carcinoma, Hepatocellular↗
PubMed2001

[A safe and simple method of percutaneous transfemoral implantation of a port-catheter access system for hepatic artery chemotherapy infusion].

The purpose of this study was to perform a simple percutaneous transfemoral implantation of a portcatheter access system using a new catheter coating for hepatic artery chemotherapy infusion, and to evaluate the complications of transfemoral infusion port implantation. The methods of treatment for complications were also studied. The port-catheter system was percutaneously implanted via femoral artery access in 180 patients with malignant liver tumors. Blood flow redistribution was performed using embolization coils. An unfixed 5 Fr catheter was placed in a hepatic artery, and connected to a port implanted subcutaneously below the level of the inguinal ligament. The success rate of implantation was 99%. Complications after placement were observed as follows: port system obstruction (9.6%); dislocation of the catheter tip (8.4%); drug toxicity (4.5%); and infection (3.4%). Notable is the avoidance of cerebral infarcts. In 3 of 17 patients with port obstruction, recanalization of the port was achieved. In 11 of 15 patients with catheter dislocation, replacement of the catheter-port system was successful. In 5 patients with hepatic artery occlusion, the replacement of a microcatheter-port access system was achieved, and hepatic artery chemotherapy infusion was resumed. This percutaneous transfemoral implantation of a catheter-port access system would seem to be a very simple and useful method for many clinical doctors, and it may improve the quality of life in patients with an unresectable malignant liver tumor.

Adolescent↗
PubMed2000

Nonredundant roles of the elongation factor MEN in postimplantation development.

The MEN/ELL gene was cloned as a fusion partner of the MLL gene in the t(11;19)(q23;p13.1) translocation, which is found in adult myeloid leukemia. MEN belongs to a family of RNA polymerase II elongation factors and dysregulated production of MEN through the MLL promoter could cause malignant transformation of myeloid cells. To pursue the physiological role and determine the requirement of the MEN gene product in mouse development, we generated knockout mice (MEN-/-) by gene targeting in embryonic stem cells. After intercrossing heterozygous mice to generate homozygous mutants, we identified no homozygotes (MEN-/-) even at E9.5, as well as after birth, by Southern analysis. Moreover, histological examinations revealed degenerative changes in nearly one-fourth of E6.5 embryos, which were gradually resorbed by E8.5. Our findings demonstrated that MEN-/- mice are embryonic lethal, and die before E6.5 and after implantation. MEN should play a nonredundant role in postimplantation development of mice.

Adult↗
PubMed2000

Effects of beta(-)-emitting (188)Re balloon in stented porcine coronary arteries: an angiographic, intravascular ultrasound, and histomorphometric study.

BACKGROUND: Restenosis within stents may be prevented by ionizing radiation from an intravascular source. METHODS AND RESULTS: A liquid beta(-) radiation ((188)Re) balloon was evaluated in a randomized and blinded porcine coronary model of stent restenosis. Group A pigs (n=17) received 0,16, 22, or 29 Gy at 0.5-mm depth, followed by stenting. Restenosis was quantified by angiography, ultrasound, and histomorphometry at 30 days. Group B (n=7) was stented first and then treated with 0 or 29 Gy with follow-up at 60 days. There was a measurable effect at 16 Gy, which improved with increasing doses. At 29 Gy, the histological stenotic area was reduced by 67% (22% versus 66% in controls, P<0.001). Radiation after stenting was equally effective; the stenotic area was reduced (21% versus 65%, P<0.001). At 16 Gy, the vessel just distal to the stent was significantly smaller than control vessels because of intimal thickening (P=0.003). Radiated vessels had distinctive histology consisting of neointimal fibrin and reduced smooth muscle cells and matrix (P<0.0001). CONCLUSIONS: (188)Re balloon brachytherapy in porcine coronary arteries results in dose-dependent and injury-independent inhibition of stent restenosis for up to 60 days. Restenosis at the borders of the irradiated zone is a potential limitation and may be related to underdosing. Brachytherapy with the (188)Re balloon appears to be safe and feasible for clinical studies.

Angioplasty, Balloon, Coronary↗
PubMed2000

Acetylation of GATA-3 affects T-cell survival and homing to secondary lymphoid organs.

Acetylation of a transcription factor has recently been shown to play a significant role in gene regulation. Here we show that GATA-3 is acetylated in T cells and that a mutation introduced into amino acids 305-307 (KRR-GATA3) creates local hypoacetylation in GATA-3. Remarkably, KRR-GATA3 possesses the most potent suppressive effect when compared with other mutants that are disrupted in putative acetylation targets. Expressing this mutant in peripheral T cells results in defective T-cell homing to systemic lymphnodes, and prolonged T-cell survival after activation. These findings have significant implications in that the acetylation state of GATA-3 affects its physiological function in the immune system and, more importantly, provides evidence for the novel role of GATA-3 in T-cell survival and homing to secondary lymphoid organs.

Acetylation↗
PubMed2000

Comparison of biotin production by recombinant Sphingomonas sp. under various agitation conditions.

Biotin production by fermentation of recombinant Sphingomonas sp./pSP304 was investigated. A complex medium containing 60g/l of glycerol and 30g/l of yeast extract was suitable for biotin production. Biotin was produced in the late logarithmic or stationary phase after glycerol starvation. The optimum pH value for biotin production was 7.0. When the dissolved oxygen concentration (DO) was controlled at a constant level, the biotin concentration produced after 120h was significantly lower than that obtained in a test tube culture. Therefore, a batchwise jar-fermentor culture with a constant agitation speed and without DO control was conducted for investigating the effect of agitation conditions on biotin production. Six types of impeller were tested: turbine-blade type, turbo-lift type, rotating mesh type (EGSTAR((R))), screw with draft tube type, Maxblend((R))type, and anchor type. With some impellers, agitation speed was also changed. Both the maximum cell concentration and biotin production varied depending on agitation conditions. Relatively high cell concentrations were attained with four of the impeller types, turbine-blade type, rotating mesh type, Maxblend((R)) type, and anchor type. Among these impellers, the turbine-blade impeller with sintered sparger was suitable for biotin production. After 120h, the cell concentration reached an OD(660) of 43 and a biotin concentration of 66mg/l was obtained, which was comparable with the results from the test tube culture. Morphological variation was also observed depending on the agitation conditions: oval-shaped, rod-shaped, and elongated-shaped cells. Biotin production was relatively high in slightly long rod-shape cells but low in elongated cells. The difference in morphology appeared to depend on the shear stress. It was found that biotin production was strongly correlated with cell length and the oxygen transfer coefficient (k(L)a); cell lengths in the range 4-7µm and k(L)a values in the range 1.5-2.0/min were found to be suitable for biotin production in jar-fermentor culture.

Journal Article↗
PubMed2000

Up-regulation of natriuretic peptides in the ventricle of Csx/Nkx2-5 transgenic mice.

A cardiac homeobox-containing gene Csx/Nkx2-5, which is essential for cardiac development, is abundantly expressed in the adult heart as well as in the heart primordia. Targeted disruption of this gene results in embryonic lethality due to abnormal heart morphogenesis. To elucidate the role of Csx/Nkx2-5 in the adult heart, we generated transgenic mice which overexpress human Csx/Nkx2-5. The transgene was expressed abundantly in the heart and the skeletal muscle. mRNA levels of several cardiac genes including natriuretic peptides, CARP, MLC2v, and endogenous Csx/Nkx2-5 were increased in the ventricle of the transgenic mice. Electron microscopic analysis revealed that the ventricular myocardium of the transgenic mice had many secretory granules, which disappeared after administration of vasopressin. These results suggest that Csx/Nkx2-5 regulates many cardiac genes and induces formation of secretory granules in the adult ventricle.

Animals↗
PubMed2000

Acquired loss of p53 induces blastic transformation in p210(bcr/abl)-expressing hematopoietic cells: a transgenic study for blast crisis of human CML.

Chronic myelogenous leukemia (CML) begins with an indolent chronic phase but inevitably progresses to a fatal blast crisis. Although the Philadelphia chromosome, which generates p210(bcr/abl), is a unique chromosomal abnormality in the chronic phase, additional chromosomal abnormalities are frequently detected in the blast crisis, suggesting that superimposed genetic events are responsible for disease progression. To investigate whether loss of p53 plays a role in the evolution of CML, we crossmated p210(bcr/abl)-transgenic (BCR/ABL(tg/-)) mice with p53-heterozygous (p53(+/-)) mice and generated p210(bcr/abl)-transgenic, p53-heterozygous (BCR/ABL(tg/-)p53(+/-)) mice, in which a somatic alteration in the residual normal p53 allele directly abrogates p53 function. The BCR/ABL(tg/-)p53(+/-) mice died in a short period compared with their wild-type (BCR/ABL(-/-)p53(+/+)), p53 heterozygous (BCR/ABL(-/-)p53(+/-)), and p210(bcr/abl) transgenic (BCR/ABL(tg/-)p53(+/+)) litter mates. They had rapid proliferation of blast cells, which was preceded by subclinical or clinical signs of a myeloproliferative disorder resembling human CML. The blast cells were clonal in origin and expressed p210(bcr/abl) with an increased kinase activity. Interestingly, the residual normal p53 allele was frequently and preferentially lost in the tumor tissues, implying that a certain mechanism facilitating the loss of p53 allele exists in p210(bcr/abl)-expressing hematopoietic cells. Our study presents in vivo evidence that acquired loss of p53 contributes to the blastic transformation of p210(bcr/abl)-expressing hematopoietic cells and provides insights into the molecular mechanism for blast crisis of human CML. (Blood. 2000;95:1144-1150)

Animals↗
PubMed2000

An isozyme of the NADP-malic enzyme of a CAM plant, Aloe arborescens, with variation on conservative amino acid residues.

In Aloe arborescens, an obligate CAM plant, Western analysis detected three major isoforms of NADP-malic enzyme (NADP-ME), 72kDa with a pI of 6.0, 65kDa with a pI of 5.6 and 65kDa with a pI of 5.5. Among them, the 65kDa protein with a pI of 5.5 was leaf-specific, and the 65kDa protein with a pI of 5.6 was found only in roots, whereas the 72kDa protein was uniformly detected in both organs. Activity staining indicated enzyme activity of both 65kDa NADP-MEs but little activity of the 72kDa protein. A cDNA clone encoding a leaf-abundant NADP-ME, AME1, was isolated. Deduced amino acid sequence of AME1 showed a high degree of homology to known NADP-MEs, but it was also found that AME1 contained substitutions on five conservative amino acid residues, some of which have been predicted to be important for their enzyme activity. Transgenic rice carrying the aloe AME1 gene efficiently produced an additional 65kDa protein with a pI of 5.5 as an active NADP-ME. These results indicate that AME1 corresponds to the leaf-specific 65kDa NADP-ME, which may be involved in CAM photosynthesis. It was also shown that substitutions of these conservative amino acid residues identified in AME1 still allowed it to give enzyme activity.

Aloe↗
PubMed2000

Intrafamilial phenotypic variation in limb-girdle muscular dystrophy type 2C with compound heterozygous mutations.

Two Japanese-Brazilian siblings with type 2C limb girdle muscular dystrophy showed a maternal 521-T deletion in exon 6 and a larger paternal deletion of exon 6 in the gamma-sarcoglycan gene. One sib was ambulant at 29 years of age, whereas the other sib was confined to a wheelchair at the age of 12. Sarcoglycan staining of the muscle was reduced in both siblings but it did not correlate with the observed variability of the clinical severity.

Adult↗
PubMed2000

Aberrant chloroplasts in transgenic rice plants expressing a high level of maize NADP-dependent malic enzyme.

NADP-dependent malic enzyme (NADP-ME) is a major decarboxylating enzyme in NADP-ME-type C4 species such as maize and Flaveria. In this study, chloroplastic NADP-ME was transferred to rice (Oryza sativa L.) using a chimeric gene composed of maize NADP-ME cDNA under the control of rice light-harvesting chlorophyll-a/b-binding protein (Cab) promoter. There was a 20- to 70-fold increase in the NADP-ME activity in leaves of transgenic rice compared to that in wild-type rice plants. Immunocytochemical studies by electron microscopy showed that maize NADP-ME was mostly localized in chloroplasts in transgenic rice plants, and that the chloroplasts were agranal without thylakoid stacking. Chlorophyll content and photosystem II activity were inversely correlated with the level of NADP-ME activity. These results suggest that aberrant chloroplasts in transgenic plants may be caused by excessive NADP-ME activity. Based on these results and the known fact that only bundle sheath cells of NADP-ME species, among all three C4 subgroups, have agranal chloroplasts, we postulate that a high level of chloroplastic NADP-ME activity could strongly affect the development of chloroplasts.

Chlorophyll↗
PubMed2000

Meiotic segregation analysis of a 14;21 Robertsonian translocation carrier by fluorescence in situ hybridization.

Meiotic segregation of chromosomes 14 and 21 in sperm from a 14;21 Robertsonian translocation carrier was analyzed with dual-color FISH using two locus-specific DNA probes (Tel 14q and LSI 21). The frequency of normal or chromosomally balanced sperm, resulting from alternate segregation, was 88.42%. The frequency of unbalanced sperm, resulting from adjacent segregation, was 11.25%. These observed frequencies deviated significantly from the theoretical frequencies (33.33% and 66.67%, respectively) based on random chromosome segregation, with sperm resulting from alternate segregation being preferentially produced in the translocation carrier. With respect to the chromosomally unbalanced sperm, the frequency of 21q disomic sperm was 2.45%, which is in agreement with the frequencies of unbalanced fetuses or offspring at the time of amniocentesis or at term (0-4.3%) reported by others. Although the frequency of 14 or 21 nullisomic sperm should be theoretically equal to that of 14q or 21q disomic sperm in both the carrier and controls, the frequency of nullisomic sperm was significantly higher than that of disomic sperm in the carrier (P=0.0009 for chromosome 14, P<0.0001 for chromosome 21) but not in the controls (P=0.091 for chromosome 14, P=0.74 for chromosome 21). This evidence suggests the occurrence of maturation arrest during spermatogenesis of the carrier.

Adult↗
PubMed2000

Recent developments in imaging diagnostics for HCC: CT arteriography and CT arterioportography evaluation of vascular changes in premalignant and malignant hepatic nodules.

We analyzed the hemodynamic properties and vascular supply changes in relation to the carcinogenesis of hepatocellular carcinoma (HCC), selecting 18 premalignant and malignant nodules less than 3 cm diameter (from 14 patients) for our study. The computed tomographic (CT) arteriography and CT arterioportography (CTAP) findings for these nodules were correlated with the histopathologic findings. The ratios of all microscopically counted arteries (normal hepatic and abnormal arteries), normal hepatic arteries, and portal veins in each nodule to those in the surrounding liver were calculated. Well differentiated lesions had low attenuation on CT arteriography and isoattenuation on CTAP. Moderately-to-poorly differentiated lesions had high attenuation on CT arteriography and low attenuation on CTAP. In well differentiated lesions, the ratios of all arteries, normal hepatic arteries, and portal veins were 1.17+/-0.10, 0.66+/-0.12, and 0.80+/-0.10, respectively. In moderately-to-poorly differentiated lesions, the ratios were 2.64+/-0.23, 0.09+/-0.03, and 0.07+/-0.03, respectively. We concluded that blood flow does not parallel the actual number of arteries seen on the histological examination of tumors. In well differentiated lesions, the combination of normal hepatic arterial degeneration and preserved portal veins results in low attenuation on CT arteriography and isoattenuation on CTAP. In advanced HCC, the combination of neoplastic (abnormal) arterial development by angiogenesis and obliteration of portal veins results in high attenuation on CTA and low attenuation on CTAP. These findings are characteristic of early and advanced stage HCC, and may reflect a combination of sequential changes in their hemodynamic states.

Aged↗