Biomedical subjects

Y Kono

Publications and source records attributed to Y Kono.

At least 19 recordsLinked to original sources

PubMed2006

[Late pseudoaneurysm formation after patch angioplasty of coarctation of the aorta; report of a case].

We report a case of a 13-year-old boy presenting with pseudoaneurysm associated with a knitted Dacron patch used to repair a coarctation of the aorta. At the age of 3 months, he had undergone patch angioplasty for a coarctation of the aorta, which develops following patent ductus arteriosus division at 2 months of age. He was treated by distal aortic arch replacement using 16 mm woven Dacron tube graft in an end-to-end fashion with open proximal anastomosis under deep hypothermic circulatory arrest. The aneurysm was in the aortic wall opposite the patch graft. There was no evidence of infection or dilatation of the patch graft. This case illustrates that repair of aortic coarctations with Dacron patches cannot be recommended.

Adolescent↗

PubMed2005

Entity evidence for differentiation between Tia and Tib types of soybean Kunitz trypsin inhibitor: detection of a novel transitional variant type between Tia and Tib in wild soybean (Glycine soja Sieb. & Zucc.).

Soybean Kunit trypsin inhibitor (SKTI) has several polymorphic types. Of these SKTI, there are large differences of nine amino acid substitutions between Tia and Tib. So far no transitional type between them has been found. A novel transitional intermediate variant between Tia and Tib was detected in 11 lines from 720 Japanese wild soybeans (Glycine soja Sieb. & Zucc.). This variant showed identical electrophoretic mobility to Tib in the Davis system polyacrylamide gel electrophoresis (PAGE), but higher electric points than other SKTI proteins (Tia, Tib, Tic) in isoelectric focusing PAGE. The genetic analysis of SKTI in F(2) seeds from a cross between the novel variant type and Tib showed that this variant type is inherited as codominant alleles in a multiple allelic system at an SKTI locus. This variant also showed inhibitory activity to trypsin. We propose the genetic symbol Ti b ( i5) for this novel variant. The sequence analysis of Tib ( i5) revealed that six nucleotides were different between Tib ( i5) and Tia, and the nucleotides of these mutated positions were identical to Tib. This causes substitution of five amino acids at the residue position 62 (Tyr-->Phe), 74 (Ser-->Arg), 114 (Met-->Val), 120 (Leu-->Ile) and 137 (Pro-->Thr). These substitutive amino acids are completely in accord with the amino acids of Tib, showing that Tib ( i5) is an intermediate between Tia and Tib types. Tib ( i5) type is widely distributed throughout seven separate areas from northeast to southwest Japan with a 1.5% frequency of total materials examined. This indicated that Tib ( i5) type did not originate from a recent mutation event, but had spread in wild soybean from ancient times.

Base Sequence↗

PubMed2004

Two amino acid substitutions in acetylcholinesterase associated with pirimicarb and organophosphorous insecticide resistance in the cotton aphid, Aphis gossypii Glover (Homoptera: Aphididae).

The complete coding sequences of two acetylcholinesterase (AChE) genes, Ace1 (orthologous to Drosophila Ace) and Ace2 (paralogous to Ace), from the cotton aphid (Aphis gossypii) were identified and sequences from carbamate resistant and susceptible strains compared. No change in the amino acid sequences was found in Ace1, while two amino acid substitutions, Ser431Phe and Ala302Ser, were detected between resistant and susceptible strains in Ace2. The position of Ser431Phe corresponds to one of fourteen aromatic residues lining the active site gorge and is located in the acyl pocket. Ala302Ser is located at one of the three residues which form the oxyanion hole in the active site of AChE. The Ser431Phe and Ala302Ser substitutions may play a role in pirimicarb and organophosphate resistance, respectively.

Acetylcholinesterase↗

PubMed2003

Pathogenicity, sequence and phylogenetic analysis of Malaysian Chicken anaemia virus obtained after low and high passages in MSB-1 cells.

Specific-pathogen-free (SPF) chickens inoculated with low passage Chicken anaemia virus (CAV), SMSC-1 and 3-1 isolates produced lesions suggestive of CAV infection. Repeated passages of the isolates in cell culture until passage 60 (P60) and passage 123 produced viruses that showed a significantly reduced level of pathogenicity in SPF chickens compared to the low passage isolates. Sequence comparison indicated that nucleotide changes in only the coding region of the P60 passage isolates were thought to contribute to virus attenuation. Phylogenetic analysis indicated that SMSC-1 and 3-1 were highly divergent, but their P60 passage derivatives shared significant homology to a Japanese isolate A2.

Animals↗

PubMed2003

NASDA next generation Aquatic Habitat for Space Shuttle and ISS.

The National Space Development Agency of Japan (NASDA) has more than 20 years of experience developing aquatic animal experiment facilities. We are now studying the next-generation aquatic animal experiment facility or the Aquatic Habitat (AQH) for both Space Shuttle and International Space Station use. A prototype breeding system was designed and tested. Medaka adult fish were able to mate and spawn in this closed circulatory breeding system, and the larvae grew to adult fish and spawned on the 45th day after hatching. The water quality-control system using nitrifying bacteria worked well throughout the medaka breeding test. For amphibians, we also conducted the African clawed toad (Xenopus laevis) breeding test with the same specimen chambers, although a part of circulation loop was opened to air. Xenopus larvae grew and completed metamorphosis successfully in the small specimen chamber. The first metamorphic climax started on the 30th day and was completed on the 38th day.

Animals↗

PubMed2003

Influence of porosity and composition of porous carriers on the uptake of nutrients.

The current paper assesses the potential of industrial solid wastes utilization such as blast furnace slag (BFS) and zeolite synthesized from fly ash (ZFA), which are effective as well as economically attractive for the uptake of phosphate and ammonium from polluted seawater. The solidification of BFS and ZFA has been developed in different proportions of BFS/ZFA (30/70, 50/50 and 70/30 (w/w)) with different porosities (25%, 40% and 52%, respectively) to cylindrical porous carriers using a Hydrothermal Hot-Pressing (HHP) method. The concentrations of heavy metals in ZFA and BFS were too low to affect the aquatic environment. The main finding is that the high rate of BFS (70%) in porous carriers enhanced phosphate uptake explained by the higher percentage of calcium (35.7%) in porous carriers and high pH conditions. The efficient ammonium uptake was observed with high rate of ZFA (70%) in porous carriers. Results found through this experimental work imply that porous carriers with BFS/ZFA proportion of 70/30 are suitable for potential practical application in the aquatic environment due to their efficient uptake of phosphate and ammonium. The choice was made upon their porosity (40%) and their compressive strength (56 kgf/cm2) which are relatively higher than those with BFS/ZFA proportion of 30/70 and 50/50.

Ammonia↗

PubMed2002

A simple method for evaluating abnormal lengthening of the QT interval during the face immersion test.

The slope of the relation between the unadjusted QT interval and heart rate during the face immersion test has been reported to be useful as an index for predicting an abnormal lengthening of the QT interval for children with nonfamilial long QT syndrome. Our goals were to determine whether we can replace the slope of the QT/heart rate relation calculated from all data with that calculated from fewer data and to determine whether we can replace the slope with the corrected QT value by heart rate (QTc value) at the minimum heart rate. We studied 19 children with a prolonged QT interval and 54 control children by using statistical analysis. The slope calculated from the selected data points (at least four) was in agreement with the slope calculated from all data, and the relationship between the slope and the QTc value at the minimum heart rate showed a high correlation. It was determined that we can replace the slope calculated from all data with that calculated from at least four data points and replace the slope with the QTc value at the minimum heart rate as an index for predicting an abnormal lengthening of the QT interval.

Adolescent↗

PubMed2002

Characterization and identification of Oya virus, a Simbu serogroup virus of the genus Bunyavirus, isolated from a pig suspected of Nipah virus infection.

A virus, named Oya virus, was isolated in Vero cell cultures from the lungs of a pig suspected of Nipah virus infection. The virus was revealed as a spherical enveloped RNA virus with a diameter of 79 nm. For identification of Oya virus, RT-PCR was performed. A common primer set for S-RNA of the Simbu serogroup of the genus Bunyavirus was able to amplify a cDNA from Oya virus RNA. The sequence data of the product revealed that the partial gene of Oya virus S-RNA segment had 65-70% homology with published cDNA sequences of Simbu serogroup viruses. The phylogenetic analysis of the data showed that the Oya virus is grouped in Simbu serogroup, but is genetically distinct from the serogroup viruses that have been analyzed molecularly. Serological surveys revealed that the virus distributed widely and densely in Malaysia.

Animals↗

PubMed2002

Isolation, identification and characterization of chicken anaemia virus in Malaysia.

A study was conducted to isolate and identify chicken anaemia virus (CAV) from field samples of clinically infected broiler chickens in Malaysia. A total of 125 samples were collected from chickens aged 2-6 weeks with clinically depressed and retarded growth, of which five samples were found positive to CAV directly by polymerase chain reaction (PCR). Later, five isolates of CAV from the respective five PCR positive samples were isolated in MDCC-MSB1 cells at passage 4 based on cytopathic effects, PCR and indirect immunofluorescent antibody test. The isolates were identified as BL-1, BL-2, BL-3, BL-4 and BL-5. These CAV isolates were found to resist treatment with chloroform and heat at 37 degrees C for 2 h, 56 degrees C for 30 min and 70 degrees C for 5 min. One of the isolates, BL-5 produced significant reduction (p < 0.001) of hematocrit values (9-19%), pale bone marrow, thymus atrophy and haemorrhages in skin/muscle when inoculated into 1-day old SPF chickens. Restriction enzyme digestion of 926 bp genomic fragments of all the isolates including Cux-1 isolate with HindIII exhibited a similar pattern of bands in 2% agarose gel. The present findings confirmed the presence of CAV in Malaysia.

Animals↗

PubMed2002

Development of a modified method for sequencing high G:C regions in chicken anemia virus genome.

Two areas in the chicken anemia virus (CAV) genome have high G:C content with secondary structures. These two G:C rich areas could not be sequenced with Perkin Elmer's Big Dye Terminator Cycle Sequencing Kit. Several modifications were carried out to solve the problem. Finally, a package of modified method was developed to sequence the high G:C areas. The result showed that the Perkin Elmer's Big Dye Terminator Cycle Sequencing Kit with the normal procedures are not suitable for sequencing the high G:C regions of the CAV genome. The present developed method made the Perkin Elmer's Kit useful for the first time to sequence the G:C rich hairpin structures of the CAV genome. The system may be useful to sequence all other G:C rich DNA templates.

Animals↗

PubMed2002

Morphometry and strain distribution of the C57BL/6 mouse aorta.

The goal of the present study was to obtain a systematic set of data along the length of the mouse aorta to study variations of morphometry (diameter, wall thickness, and curvature), strain, and stress of the mouse aorta. Five mice were imaged with a 13-MHz ultrasound probe to determine the in vivo diameter along the aorta. A cast was made of these aortas to validate the ultrasonic diameter measurements. The root mean squared and systematic errors for these measurements were 12.6% and 6.4% of the mean ultrasound diameter, respectively. The longitudinal variations of geometry, stress, and strain from the aortic valve to the common iliac bifurcation were documented. Our results show that the residual circumferential strain leads to a uniformity of transmural strain of the aorta in the loaded state along the entire length of the aorta. Furthermore, we validated the incompressibility condition along the length of the aorta. These data of normal mice will serve as a reference state for the study of disease in future knockout models.

Animals↗

PubMed2001

Condition of microcephaly, growth retardation, joint contractures, atopic dermatitis, and mental retardation in two Japanese sisters: a new autosomal recessive MCA/MR syndrome?

We report on two sisters in a family with a hitherto undescribed MCA/MR condition characterized by growth retardation, severe microcephaly, a peculiar facies, congenital contractures of the interphalangeal and patellar joints, atopic dermatitis, and growth and developmental delay. The disorder in the family we describe is similar to but clearly distinguished from tricho-rhino-phalangeal syndromes or Bavinck syndrome. We propose that the condition in the sisters represents a new autosomal recessive MCA/MR syndrome.

Abnormalities, Multiple↗

PubMed2001

Characterization and subcellular localization of KCNQ1 with a heterozygous mutation in the C terminus.

Numerous mutations in KCNQ1, a gene encoding the alpha -subunit of cardiac delayed rectifier potassium channels, have been found in long QT syndrome (LQTS). Among them, several mutations in the C terminus have been shown to cause autosomal recessive or subclinical autosomal dominant LQTS. Here, we report a heterozygous mutation, T587M, which is also in the KCNQ1 C-terminal domain. The same mutation was found in three independent probands that were clearly symptomatic with family history of cardiac sudden death. Functional assay using a heterologous expression system with a mammalian cell line (COS7 cells) revealed that the mutant displayed neither functional channels when expressed alone nor dominant-negative effect when co-expressed with wild-type (WT) KCNQ1. To examine the cellular trafficking of KCNQ1, green fluorescent protein (GFP) was tagged to the cytoplasmic C terminus of WT or mutant KCNQ1. This procedure did not affect the essential properties of expressed WT KCNQ1 channels. On confocal microscopic images, GFP-tagged WT KCNQ1 showed a plasma membrane fluorescence pattern, whereas the GFP-tagged mutant showed a perinuclear fluorescence pattern. Co-expression of the mutant with GFP-tagged WT KCNQ1 did not influence its normal cellular transport. Therefore, the T587M mutant cannot traffic to the plasma membrane and may form no subunit assembly with WT KCNQ1. These findings provide a novel molecular basis for the clinical finding that this C-terminal mutation produced a severe form of RWS-type LQTS.

Adolescent↗

PubMed2001

Update of daily intake of PCDDs, PCDFs, and dioxin-like PCBs from food in Japan.

Total diet study (TDS) samples of 14 food groups from 16 locations in Japan, collected in 1999 and 2000, were analyzed for polychlorinated dibenzo-p-dioxins (PCDDs), dibenzofurans (PCDFs), and dioxin-like polychlorinated biphenyls (dioxin-like PCBs) to estimate the update of daily intake of these contaminants from food. The mean daily intake of toxic equivalency (TEQ) for an adult weighing 50 kg, calculated at non-detected isomer concentrations equal to zero (ND = 0), was estimated to be 2.25 pg TEQ/kg b.w./day. When non-detected isomer concentrations are assumed to be equal to half of the limits of detection (ND = 1/2 LOD), the mean daily intake was estimated to be 3.22 pg TEQ/kg b.w./day. These values were below the tolerable daily intake (TDI) of 4 pg TEQ/kg b.w. for PCDD/Fs and dioxin-like PCBs set in Japan. In both the estimates, the mean daily intakes were highest from fish and shellfish (76.9% at ND = 0 and 53.9% at ND = 1/2 LOD of the total TEQs), followed by those from meat and eggs (15.5% at ND = 0 and 11.7% at ND = 1/2 LOD of the total TEQs). Congener specific data revealed that these total TEQ levels were dominated by 1,2,3,7,8-PeCDD, 2,3,4,7,8-PeCDF and 3,3',4,4',5-PeCB in each case (71.7% at ND = 0 and 63.1% at ND = 1/2 LOD of the total TEQs). The dioxin-like PCBs (non-ortho and mono-ortho PCBs) accounted for about 50% of these total TEQs. These data will be very useful in the risk assessment of PCDD/Fs and dioxin-like PCBs from food in Japan.

Adult↗

PubMed2001

Modulation of tetrodotoxin-resistant sodium channels by dihydropyrazole insecticide RH-3421 in rat dorsal root ganglion neurons.

The effects of the dihydropyrazole insecticide RH-3421 on the retrodotoxin-resistant (TTX-R) voltage-gated sodium channels in rat dorsal root ganglion (DRG) neurons were studied using the whole-cell patch clamp technique. RH-3421 at 10 nM to 1 microM completely blocked action potentials. The sodium currents were irreversibly suppressed by 1 microM RH-3421 in a time- and a dose-dependent manner and the IC50 value of RH-3421 was estimated to be 0.7 microM after 10 min of application. RH-3421 blocked the sodium currents to the same extent over the entire range of test potentials. The sodium conductance-voltage curve was not shifted along the voltage axis by 1 microM RH-3421 application In contrast, both fast and slow steady-state sodium channel inactivation curves were shifted in the hyperpolarizing direction in the presence of 1 microM RH-3421. It was concluded that RH-3421 bound to the resting and inactivated sodium channels to cause block with a higher affinity for the latter state.

Action Potentials↗

PubMed2001

Fenitroxon insensitive acetylcholinesterases of the housefly, Musca domestica associated with point mutations.

The cDNA of AChE in the housefly, Musca domestica, was sequenced and individual flies were genotyped by this gene in an inhibition assay of AChE activity with an organophaspate, fenitroxon. Mutations at Gly(342) and Tyr(407), which are reportedly conserved in resistant strains of Drosophila, were associated with the insensitivity to fenitroxon. Two other mutations, Ile(162) and Val(260), did not have an apparent effect on insensitivity. However, the four mutations are located in the active site of the enzyme, and therefore the non-neutral mutations in this gene are considered to cause the insensitivity of AChE in the development of insecticide resistance of the housefly.

Acetylcholinesterase↗

PubMed2001

B-mode enhancement of the liver with microbubble contrast agent: a blinded study in rabbits with VX2 tumors.

RATIONALE AND OBJECTIVES: The purpose of this study was to evaluate the accuracy of contrast material-enhanced sonography in the detection of liver lesions by using an animal model. MATERIALS AND METHODS: A total of 36 rabbits, 12 normal and 24 with one, two, or more VX2 tumors implanted percutaneously, were imaged on an Acuson 128XP/10 with a 7-MHz sector transducer by a sonographer blinded to the study assignments. The sonographer assigned rabbits to four groups (no, one, two, more than two tumors) based on the number of lesions detected before and then after the intravenous bolus injection of 0.5 mL of AF0150. S-VHS video segments or pre- and postcontrast images were separated, randomized, and evaluated by a blinded reader. Necropsy served as the gold standard. RESULTS: Classification of rabbits as normal or tumor bearing on the precontrast images produced three false-positive results and three false-negative results for the blinded sonographer and six false-positive results and two false-negative results for the blinded reader. On postcontrast images, all rabbits were correctly classified by both observers. The correlation of the classification of whether rabbits had no, one, two, or more tumors relative to the pathologic classification on precontrast images was poor to fair (K = 0.349 +/- 0.099 for the sonographer and 0.274 +/- 0.111 for the reader), whereas the postcontrast correlation was good to excellent (K = 0.924 +/- 0.099 for the sonographer and 0.809 +/- 0.076 for the reader). CONCLUSION: AF0150 markedly increased the ability of the sonographer and the blinded reader to distinguish normal from tumor-bearing animals and improved the classification of rabbits with more than one liver tumor.

Animals↗

PubMed2001

Comparative linkage map development and identification of an autosomal locus for insensitive acetylcholinesterase-mediated insecticide resistance in Culex tritaeniorhynchus.

A comparative linkage map for Culex tritaeniorhynchus was constructed based on restriction fragment length polymorphism markers using cDNAs from Aedes aegypti. Linear orders of marker loci in Cx. tritaeniorhynchus were identical to Culex pipiens wherein chromosomes 2 and 3 reflect whole-arm rearrangements compared to A. aegypti. However, the sex determination locus in Cx. tritaeniorhynchus maps to chromosome 3, in contrast to Cx. pipiens and Ae. aegypti where it is located on chromosome 1. Our results indicate that insensitive acetylcholinesterase (AChE)-mediated organophosphate resistance is controlled by a single major gene (AChE) on chromosome 2, while the AChE structural gene (Ace) is located on chromosome 1. No evidence for a second Ace gene was observed, even under very low stringency hybridization conditions.

Acetylcholinesterase↗