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T Komatsuda

Publications and source records attributed to T Komatsuda.

At least 19 recordsLinked to original sources
PubMed2006

Portal systemic shunt through the renal vein.

BACKGROUND: Despite the semi-routine use of color Doppler sonography for evaluating portal circulation abnormalities, there is a relative paucity of detailed color Doppler findings of portal systemic (P-S) shunt through the renal vein (P-SR shunt). METHODS: We reviewed the color Doppler findings of 18 patients with P-SR shunt to determine its clinical significance and appropriate scanning techniques for diagnosing accurately P-SR shunt. RESULTS: The splenorenal shunt was imaged as a highly tortuous vessel at the splenic hilum, which then coursed backward behind the spleen. Splenic vein flow was reversed or very slow. The gastrorenal shunt originated from the splenic vein, coursed backward, and joined the left renal vein. Flow direction in the splenic vein was always hepatopetal. The P-S shunt through the right renal vein originated from duodenal or jejunal varices, coursed posterolaterally, and joined the right renal vein at the renal hilum. CONCLUSION: Familiarity with these color Doppler findings will help increase the diagnostic confidence of P-SR shunt by color Doppler sonography.

Adult↗
PubMed2005

Structural and distributional variation of mitochondrial rps2 genes in the tribe Triticeae (Poaceae).

The mitochondrial rps2 gene from barley, like that of rice, wheat, and maize, has an extended open reading frame (ORF) at the 3'-region when compared to that from lower plants. However, the extended portions are variable among these cereals. Since barley and wheat belong to the same tribe (Triticeae), it would be interesting to know when and where the two types of rps2 were generated during evolution. To determine this, we utilized the mitochondrial (mt) DNA sequence to examine variations of the rps2 genes in the tribe Triticeae. By means of the variable 3'-region, the distribution of barley (B)-type and wheat (W)-type rps2 sequences was studied in 19 genera of the tribe. The B-type sequence was identified in 10 of the 19 genera, whereas the W-type sequence was present in all 19 genera. Thus, ten of the examined genera have both types of rps2 sequences due to the presence of two copies of the gene. The W-type sequence was also present in the tribe Bromeae and the B-type sequence was also found in Aveneae and Poeae. Phylogenetic trees based on the B-type and W-type sequences were different from those based on other molecular data. This suggests that the mitochondrial genome in Triticeae has a unique evolutionary history.

Amino Acid Sequence↗
PubMed2004

High-density AFLP map of nonbrittle rachis 1 (btr1) and 2 (btr2) genes in barley (Hordeum vulgare L.).

Wild relatives of barley disperse their seeds at maturity by means of their brittle rachis. In cultivated barley, brittleness of the rachis was lost during domestication. Nonbrittle rachis of occidental barley lines is controlled by a single gene (btr1) on chromosome 3H. However, nonbrittle rachis of oriental barley lines is controlled by a major gene (btr2) on chromosome 3H and two quantitative trait loci on chromosomes 5HL and 7H. This result suggests multiple mutations of the genes involved in the formation of brittle rachis in oriental lines. The btr1 and btr2 loci did not recombine in the mapping population analyzed. This result agrees with the theory of tight linkage between the two loci. A high-density amplified fragment-length polymorphism (AFLP) map of the btr1/btr2 region was constructed, providing an average density of 0.08 cM/locus. A phylogenetic tree based on the AFLPs showed clear separation of occidental and oriental barley lines. Thus, barley consists of at least two lineages as far as revealed by molecular markers linked to nonbrittle rachis genes.

Chromosome Mapping↗
PubMed2004

Identification and mapping of cleistogamy genes in barley.

Cleistogamy is a closed type of flowering with ensured self-pollination and an important trait to study evolutionary development in flower organs, reproduction systems, gene flow, and disease control. Still, very limited information is available about the genetic control and regulatory mechanism of this trait in barley. In this work, from the eight crosses between cleistogamous and chasmogamous accessions, five crosses generated chasmogamous F1 plants and their F2 plants segregated as 3 chasmogamous:1 cleistogamous, whereas three crosses generated cleistogamous F1 plants, and their F2 plants segregated as 1 chasmogamous:3 cleistogamous. Although a single gene was responsible for the control of cleistogamy in these two groups of crosses, the direction of dominance was opposite, suggesting two genes, cly1 and Cly2, for the genetic control of cleistogamy in barley. Epistatic type of gene interaction between the two loci was detected. In the analysis of 99 recombinant inbred lines of 'Azumamugi' x 'Kanto Nakate Gold' and doubled haploid lines of 'Harrington' x 'Mikamo Golden', where in both crosses F1 was chasmogamous, the cly1 locus has been mapped on chromosome 2HL. Using the analysis of the F2 population of 'Misato Golden' and 'Satsuki Nijo' where F1 was cleistogamous, the Cly2 locus was mapped in the same region of chromosome 2HL. Because the cly1 and Cly2 loci were mapped in the same region in these three different mapping populations, it was concluded that the expression of cleistogamy is under the control of two tightly linked genes or different alleles of the same gene.

Chromosome Mapping↗
PubMed2004

Comparative high resolution map of the six-rowed spike locus 1 (vrs1) in several populations of barley, Hordeum vulgare L.

Multiple alleles at the vrs1 locus control the development and fertility of the lateral spikelets of barley (Hordeum vulgare L.), which is a key character in the study of yield, utilization and domestication. In this study, six linkage maps of the vrs1 locus were constructed, using different mapping populations developed from nine different barley cultivars (H. vulgare subsp. vulgare) or mutant and wild barley (H. vulgare subsp. spontaneum). A total of 8387 chromosomes (gametes) were sampled for analysis based on a hypothesis that orders of marker loci were the same over the different parental lines. The results showed that four markers and the vrs1 locus in all cases were arranged in the same order, which was in a good agreement with the hypothesis. This makes the linkage maps suitable for the positional cloning of the alleles at the vrs1 locus.

Alleles↗
PubMed2004

Identification of AFLP makers linked to non-seed shattering locus (sht1) in buckwheat and conversion to STS markers for marker-assisted selection.

Shattering habit in buckwheat has two forms: brittle pedicel and weak pedicel. Brittle pedicel is observed in wild buckwheat, but not in cultivated buckwheat. Brittle pedicel in buckwheat is produced by two complementary, dominant genes, Sht1 and Sht2. The sht1 locus is linked to the S locus; almost all common buckwheat cultivars possess the allele sht1. To detect molecular makers linked to the sht1 locus, we used amplified fragment-length polymorphism (AFLP) analysis in combination with bulked segregant analysis of segregating progeny of a cross between a non-brittle common buckwheat and a brittle self-compatible buckwheat line. We screened 312 primer combinations and constructed a linkage map around the sht1 locus by using 102 F2 plants. Five AFLP markers were linked to the sht1 locus. Two of these, e54m58/610 and e55m46/320, cosegregated with the sht1 locus without recombination. The two AFLP markers were converted to STS markers according to the sequence of the AFLPs. The STS markers are useful for marker-assisted selection of non-brittle pedicel plants and provides a stepping-stone for map-based cloning and characterization of the gene encoding non-brittle pedicel.

Base Sequence↗
PubMed2002

A DNA marker closely linked to the vrs1 locus (row-type gene) indicates multiple origins of six-rowed cultivated barley ( Hordeum vulgare L.).

The origin of six-rowed cultivated barley was studied using a DNA marker cMWG699 closely linked to the vrs1 locus. Restriction patterns of the PCR-amplified product of the cMWG699 locus were examined in 280 cultivated ( Hordeum vulgare ssp. vulgare) and 183 wild ( H. vulgare ssp. spontaneum) barleys. Nucleotide sequences of the PCR products were also examined in selected accessions. Six-rowed cultivated barleys were divided into two distinct groups, types I and II. Type I six-rowed cultivated barley was distributed widely while type II six-rowed cultivated barley was found only in the Mediterranean region. The type I sequence was also found in a wild barley accession from Turkmenistan whereas the type II sequence was also found in a two-rowed cultivated barley from North Africa and a wild barley from Morocco. These results suggested that the six-rowed type I and II barleys were derived from two-rowed type I and II barleys, respectively, by independent mutations at the vrs1 locus.

Journal Article↗
PubMed2001

Mesenteric lipoma: report of a case with emphasis on US findings.

Mesenteric lipoma (ML) is a relatively rare disease that has been very infrequently reported. We present the clinical data and medical imaging results of an asymptomatic case with ML incidentally detected by sonography (US). On US the lesion was imaged as a well-demarcated hypoechoic mass with multiple linear echoes. The mass also changed location under probe compression. The lesion was imaged as a clearly demarcated non-enhanced homogeneous fat-density mass on CT. Color Doppler US and angiography confirmed the avascular nature of the mass. Knowledge of the US findings in this case is useful for the diagnosis of ML.

Adult↗
PubMed2001

Construction of a genetic map of barley (Hordeum vulgare L.) cross 'Azumamugi' x 'Kanto Nakate Gold' using a simple and efficient amplified fragment-length polymorphism system.

We have devised a simple and efficient amplified fragment-length polymorphism (AFLP) system consisting of small slab gels, a discontinuous buffer system, and silver staining. Using this system, a single worker developed a barley map with 227 polymorphic fragments in 2 months. As a mapping population, 99 recombinant inbred lines of barley cultivars 'Azumamugi' x 'Kanto Nakate Gold' were used. Most of the 227 AFLP fragments showed a Mendelian segregation ratio of 1:1, and all were assigned to the seven barley chromosomes. Thus, these fragments are useful as molecular markers. They were integrated with 40 previously characterized sequence-tagged sites, 3 isozymes, and 2 morphological markers to construct an integrated map. The resulting map covered 925.6 cM with 272 markers (detecting 150 loci) at an average interval of 6.5 cM/locus. This system greatly simplifies map construction.

Chromosome Mapping↗
PubMed2000

Congenital absence of the horizontal portion of the left portal vein: ultrasound findings.

Congenital absence of the horizontal portion of the left portal vein is very rare and has been very reported sporadically. We present three such cases referred from other hospitals with a diagnosis of intrahepatic vascular anomaly. Color Doppler ultrasound not only confirmed the diagnosis but also allowed a quantitative measurement of blood flow in these cases. Although it is a very rare condition, knowledge of the ultrasound and color Doppler findings helps in establishing the diagnosis of this congenital anomaly.

Congenital Abnormalities↗
PubMed2000

Long-standing painless intussusception in adults.

Long-standing painless intussusception in adults is considered to be rare. We report three such cases with an emphasis on color Doppler results. In our three cases the indication for abdominal US was a palpable mass in all these cases, and intussusception was detected by US at a time when the patients had only very mild abdominal discomfort. Persistence of sufficient blood flow, as was suggested by the color Doppler results, was thought to be the most likely pathomechanism of long-standing painless intussusception. The underlying disease was tuberculosis in two of the three cases. Thus, when encountering patients with painless intussusception, tuberculosis must be kept in mind.

Aged↗
PubMed1999

Primary leiomyosarcoma of the greater omentum.

We report a case of primary greater omental leiomyosarcoma successfully resected by omentectomy. Palpation of a painless abdominal mass at physical examination motivated medical imaging examination. Ultrasound visualized accurately the internal structure of the lesion but failed to determine the site of origin. Computed tomography and angiography determined the greater omental origin of the tumor before surgery. A review of the literature is also presented.

Adult↗
PubMed1999

A nucleotide sequence linked to the vrs1 locus for studies of differentiation in cultivated barley (Hordeum vulgare L.).

A PCR-amplified DNA, cMWG699, is linked to the vrs1 (formerly v) locus controlling 2- and 6-rowed spikelets. Restriction analysis of the amplified DNA of 65 varieties from Europe, America, and East Asia revealed 3 alleles, named types K, A and D. Two-rowed varieties were mostly of type K allele, and 6-rowed varieties were mostly of type A allele. The type D allele was found only in three 6-rowed varieties. Sequence comparison of these alleles revealed that the type A allele is more closely related to the type K allele than to the type D allele. The sequence analysis also suggested that the types A and D alleles diverged earlier than when 6-rowed barley arose. On the assumption that 2-rowed barleys were the ancestors of 6-rowed barley, 6-rowed barleys with types A and D alleles probably differentiated from 2-rowed barleys with type A and D alleles, respectively, by independent mutations on the vrs1 locus.

Alleles↗
PubMed1999

Phylogeny in the genus Hordeum based on nucleotide sequences closely linked to the vrs1 locus (row number of spikelets).

The phylogenetic relationship between four basic genomes designated H, I, Xa, and Xu in the genus Hordeum was studied using a nuclear DNA sequence. The sequence, cMWG699, is single copy in the H. vulgare genome, and tightly linked to the vrs1 locus which controls two- and six-rowed spikes. DNA fragments homologous to cMWG699 were amplified from diploid Hordeum species and the nucleotide sequences were determined. A phylogeny based on both base substitutions and an insertion-deletion event showed that the H- and Xa-genome groups are positioned in one monophyletic group indicating that the Xa-genome taxa should be included in the H-genome group. The large H-genome group is highly homogeneous. The I and Xu genomes are distinctly separated from H and Xa, and form sister groups. Another phylogeny pattern based on data excluding the insertion-deletion gave a result that the Xa genome forms a sister group to the H-genome group. The difference between the H and Xa genomes was affected only by a single base insertion-deletion event, thus the H and Xa genomes are likely to be closely related. The I and Xu genomes were again distinctly separated from the H and Xa genomes.

Base Sequence↗
PubMed1998

Anterior abdominal wall pathologies detected by high-frequency annular array.

AIM AND METHODS: In 1850 patients, high-frequency (HF: 7.5-10 MHz) annular array US examination was performed to evaluate the value of HF annular US in the detection of pathologies of the anterior abdominal wall. RESULTS: HF annular US revealed pathological lesions (metastasis, benign tumor, lymphoma, hematoma, fistula, hernia, abscess) in 37 patients. The lesions were detected by conventional medium-frequency (3.5-3.75 MHz) US in only 8 of 37 cases (21.6%). HF annular US added information that altered clinical management in 19 cases (51.4%), predominantly in cases with tumors and fistulas. CONCLUSION: The addition of HF annular US to a conventional US examination increases the detectability of small, but clinically important pathologies in the anterior abdominal wall.

Abdominal Muscles↗
PubMed1998

Portal vein thrombosis associated with antiphospholipid syndrome: a case report.

We present a case of portal vein thrombosis associated with antiphospholipid syndrome (APS). The patient had an end-stage renal disease and underwent hemodialysis, and a portal thrombus was incidentally found in the main portal vein by color Doppler sonography. The patient is followed up now with long-term anticoagulant therapy. This experience suggests that color Doppler sonography be performed for patients with APS to improve their management.

Antiphospholipid Syndrome↗
PubMed1998

Sonographic findings of malignant fibrous histiocytoma of the mesentery-report of two cases.

We present two cases of malignant fibrous histiocytoma (MFH) of the mesentery. A whorled internal structure observed on sonogram and large feeding and draining vessels demonstrated on color Doppler sonogram in these cases were worth noticing. When sonography reveals an abdominal tumor with such findings, although very rare, the possibility of a MFH of the mesentery must be considered. We also review briefly the literature.

Histiocytoma, Benign Fibrous↗